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The study of lattice gauge theories with Monte Carlo simulations is hindered by the infamous sign problem that appears under certain circumstances, in particular at non-zero chemical potential. So far, there is no universal method to overcome this problem. However, recent years brought a new class of non-perturbative Hamiltonian techniques named tensor networks, where the sign problem is absent. In previous work, we have demonstrated that this approach, in particular matrix product states in 1+1 dimensions, can be used to perform precise calculations in a lattice gauge theory, the massless and massive Schwinger model. We have computed the mass spectrum of this theory, its thermal properties and real-time dynamics. In this work, we review these results and we extend our calculations to the case of two flavours and non-zero chemical potential. We are able to reliably reproduce known analytical results for this model, thus demonstrating that tensor networks can tackle the sign problem of a lattice gauge theory at finite density
Die chemischen und physikalischen Eigenschaften eines Festkörpers sind vom inneren Aufbau des Festkörpers abhängig. Die Methode der Wahl zur Bestimmung von Kristallstrukturen sind Beugungsexperimente. Fehlordnungen in den Kristallstrukturen werden mit Beugungsexperimenten häufig nur unzureichend ausgewertet oder ignoriert. In dieser Arbeit wurden die (möglichen) Stapelfehlordnungen der Aminosäuren DL-Norleucin und DL-Methionin, sowie von Chloro (phthalocyaninato)aluminium(III) untersucht. Dazu wurden Gitterenergieminimierungen mit Kraftfeld- und quantenchemischen Methoden an einem Satz geordneter Modellstrukturen durchgeführt.
In den Kristallstrukturen der α- und β-Phasen von DL-Norleucin ordnen sich die Moleküle in Doppelschichten an und bilden jeweils eine Schichtstruktur mit unterschiedlicher Stapelsequenz. Röntgenbeugungsexperimente an Kristallen dieser Verbindung zeigen charakteristische diffuse Streuung. Die durchgeführten Gitterenergieminimierungen reproduzieren die experimentelle Stabilitätenreihenfolge der beiden Polymorphe von DL-Norleucin. Die berechneten Gitterenergien zeigen, dass es für DL-Norleucin bevorzugte Stapelsequenzen gibt. Die Gitterenergien und Molekülstrukturen einer einzelnen Doppelschicht sind dabei von der Anordnung benachbarter Doppelschichten abhängig. Zudem wurden Strukturmodelle mit Stapelsequenzen aufgebaut, die aus kristallographischer Sicht möglich sind, jedoch experimentell nicht beobachtet wurden, und deren Gitterenergie berechnet. Diese Stapelsequenzen liefern im Vergleich zu den energetisch günstigsten Stapelsequenzen einen signifikanten Energieverlust und treten daher selten auf. Ausgehend von den Ergebnissen der Gitterenergieminimierungen mit DFT-D-Methoden wurden Stapelwahrscheinlichkeiten mit Hilfe der Boltzmann-Statistik berechnet. Es wurde ein großes geordnetes Modell mit einer Stapelsequenz gemäß der Stapelwahrscheinlichkeiten aufgebaut. Dieses Modell wurde verwendet, um Beugungsexperimente zu simulieren und mit experimentellen Daten zu vergleichen. Die theoretischen und experimentellen Beugungsdaten waren in guter Übereinstimmung.
Die Moleküle in den Kristallstrukturen der α- und β-Phasen von DL-Methionin bilden Doppelschichten. Die beiden Phasen unterscheiden sich in der Stapelung der Doppelschichten und der Molekülkonformation. Es wurden Gitterenergieminimierungen sowohl mit Kraftfeld-Methoden als auch mit DFT-DMethoden an geordneten Modellen mit unterschiedlichen Stapelsequenzendurchgeführt. Die experimentell bestimmte Stabilitätenreihenfolge der Polymorphe von DL-Methionin bei tiefen Temperaturen wurde durch die Ergebnisse der kraftfeldbasierten Rechnungen reproduziert. Die Modellstrukturen wurden während den Rechnungen moderat verzerrt. Die Bandbreite der relativen Energien aller Modelle ist relativ gering, sodass eine Stapelfehlordnung aus thermodynamischer Sicht nicht ausgeschlossen werden kann. In der Regel liefern Gitterenergieminimierungen mit DFT-D Methoden genauere Ergebnisse. Die Modellstrukturen wurden während den Rechnungen nur leicht verzerrt. Allerdings unterscheidet sich das Energieranking zwischen den Kraftfeld- und DFT-D-Methoden deutlich. Die experimentell bestimmte Stabilitätenreihenfolge der Polymorphe von DL-Methionin wurde mit DFT-D-Methoden nicht reproduziert. Die Energieunterschiede zwischen den beiden Polymorphen (ΔE = 1,60 kJ∙mol−1 (DFT-D2) bzw. ΔE = 0,83 kJ∙mol−1 (DFT-D3)) sind relativ gering und liegen im Fehlerbereich der Methode. Die Bandbreite der relativen Energien aller Strukturmodelle beträgt nur etwa 1,8 kJ∙mol−1. Auf dieser Grundlage ist eine Stapelfehlordnung in den Kristallstrukturen von DL-Methionin möglich, jedoch nicht experimentell beobachtet. Nicht nur die Kraftfeld-,sondern auch die DFT-D-Methoden scheinen für die Berechnung der Gitterenergien für das System DL-Methionin nicht genügend genau zu sein. Die erhaltenen relativen Energien sollten daher mit Vorsicht betrachtet werden.
Chloro(phthalocyaninato)aluminium(III) (AlPcCl) bildet eine Schichtstruktur, in der sich die Moleküle zu Doppelschichten zusammenlagern. Die 1984 durchgeführte Kristallstrukturbestimmung [98] lieferte auf Grund der schlechten Datenqualität nur eine ungenaue Kristallstruktur. Die asymmetrische Einheit enthält zwei Moleküle, von denen das eine Molekül geordnet, das andere fehlgeordnet ist. Die Kristallstruktur von AlPcCl ist fehlgeordnet, weil eine einzelne Doppelschicht von Molekülen eine tetragonale P4/n-Symmetrie aufweist, die vier symmetrieäquivalente Möglichkeiten bietet, eine zweite Doppelschicht auf einer ersten Doppelschicht zu platzieren. Mit Hilfe der OD-Theorie wurde ein Satz geordneter Modelle mit verschiedenen Stapelsequenzen aufgestellt und die Gitterenergie zunächst mit Kraftfeld-Methoden und anschließend mit DFT-DMethoden berechnet. Auf Grund unzureichender Parametrisierung, musste das Kraftfeld an das System AlPcCl angepasst werden. Die Modellstrukturen werden während den Kraftfeld-Rechnungen nur leicht verzerrt. Die berechneten Gitterenergien hängen allerdings stark von der verwendeten Parametrisierung und den Atomladungen ab und sollten daher mit Vorsicht betrachtet werden. Genauere Ergebnisse erzielten Gitterenergieminimierungen mit DFT-D-Methoden. Die verschiedenen Stapelsequenzen haben eine ähnliche Energie, was die Stapelfehlordnung in der Kristallstruktur von AlPcCl erklärt. Die Überlagerung der vier energetisch günstigsten geordneten Stapelsequenzen führt zu einer gemittelten Struktur, die sehr gut die fehlgeordnete experimentelle Kristallstruktur von AlPcCl erklärt.
Motivated by a recent finding of an exact solution of the relativistic Boltzmann equation in a Friedmann–Robertson–Walker spacetime, we implement this metric into the newly developed transport approach Simulating Many Accelerated Strongly-interacting Hadrons (SMASH). We study the numerical solution of the transport equation and compare it to this exact solution for massless particles. We also compare a different initial condition, for which the transport equation can be independently solved numerically. Very nice agreement is observed in both cases. Having passed these checks for the SMASH code, we study a gas of massive particles within the same spacetime, where the particle decoupling is forced by the Hubble expansion. In this simple scenario we present an analysis of the freeze-out times, as function of the masses and cross sections of the particles. The results might be of interest for their potential application to relativistic heavy-ion collisions, for the characterization of the freeze-out process in terms of hadron properties.
The KER for electron capture of vibrational cooled HeH+ and H3 + ions at 20 keV from residual gas atoms has been measured in the Frankfurt Low Energy Storage Ring (FLSR). At a vacuum in the order of few 10-11 mbar, this residual gas consists to 99% of H2 molecules. For the identification of the recoil products of this reaction, a recoil spectrometer (with an MCP-detector with position and time sensitive read out) was installed at one of the focus points (IP) in the FLSR. The planned extension of this set up by a gas target to a full COLTRIMS reaction microscope will be discussed.
Information theory provides a formal framework within which information processing and its disorders can be described. However, information theory has rarely been applied to modeling aspects of the cognitive neuroscience of schizophrenia. The goal of this article is to highlight the benefits of an approach based on information theory, including its recent extensions, for understanding several disrupted neural goal functions as well as related cognitive and symptomatic phenomena in schizophrenia. We begin by demonstrating that foundational concepts from information theory—such as Shannon information, entropy, data compression, block coding, and strategies to increase the signal-to-noise ratio—can be used to provide novel understandings of cognitive impairments in schizophrenia and metrics to evaluate their integrity. We then describe more recent developments in information theory, including the concepts of infomax, coherent infomax, and coding with synergy, to demonstrate how these can be used to develop computational models of schizophrenia-related failures in the tuning of sensory neurons, gain control, perceptual organization, thought organization, selective attention, context processing, predictive coding, and cognitive control. Throughout, we demonstrate how disordered mechanisms may explain both perceptual/cognitive changes and symptom emergence in schizophrenia. Finally, we demonstrate that there is consistency between some information-theoretic concepts and recent discoveries in neurobiology, especially involving the existence of distinct sites for the accumulation of driving input and contextual information prior to their interaction. This convergence can be used to guide future theory, experiment, and treatment development.
For the class of balanced, irreducible Pólya urn schemes with two colours, say black and white, limit theorems for the number of black balls after n steps are known. Depending on the ratio of the eigenvalues of the replacement matrix, two regimes of limit laws occur: almost sure convergence to a non-degenerate random variable whose distribution depends on the initial composition of the urn and that is known to be not normally distributed and weak convergence to the normal distribution. In this thesis, upper bounds on the rates of convergence in both the non-normal limit case and the normal limit case are given.
Die Verarbeitung während des Hörprozesses von Säugetieren verläuft von der Kochlea mit den inneren und äußeren Haarsinneszellen (äHZ) über afferente Nervenbahnen bis zum auditorischen Kortex (AK). Die daran beteiligten Schaltstationen und deren Funktion sind überwiegend aufgeklärt. Die Hörbahn ist zudem in besonderer Weise durch efferente Rückkopplungen gekennzeichnet, die interne Modulationen sowie sekundäre Reaktionen auf den Reiz ermöglichen. Anatomisch betrachtet verlaufen efferente Projektionen vom AK zu sämtlichen am Hörprozess beteiligten Kerngebieten. Vom Olivenkomplex erfolgt über mediale und laterale Fasern eine Innervation der äHZ bzw. des Hörnervs. Trotz der gut beschriebenen Anatomie ist die funktionelle Beziehung zwischen dem AK und der Peripherie weitgehend ungeklärt. In der vorliegenden Arbeit wurde der funktionelle Zusammenhang vom AK zu den äHZ in der mongolischen Wüstenrennmaus untersucht. Dafür wurde entweder eine pharmakologische Blockierung der Kortexaktivität durch den Natriumkanalblocker Lidocain erzeugt oder eine Aktivierung der Kortexaktivität durch die Anwendung elektrischer Reize ausgelöst. Der Einfluss der Manipulationen wurde in der Kochlea mittels Messungen von Distorsionsprodukt-otoakustischen Emissionen (DPOAE) erfasst. Diese entstehen durch die nichtlineare Verstärkung leiser Schallsignale durch die äHZ zur Erzielung hoher Sensitivität und Frequenzauflösung. Die DPOAE treten als kubische (z. B. 2f1-f2) und quadratische (z. B. f2-f1) Verzerrungen auf und geben Aufschluss über unterschiedliche Parameter der äHZ-Verstärkungsfunktion.
Die Lidocainversuche wurden entweder kontra- oder ipsilateral zur DPOAE-Messung durchgeführt. In beiden Konstellationen traten nach der Lidocaininjektion Erhöhungen und Verringerungen der DPOAE-Pegel im Vergleich zur Basismessung oder unveränderte DPOAE-Pegel auf. Im Mittel lagen die Pegeländerungen bei ca. 11 dB, in Einzelfällen betrugen sie bis zu 44,8 dB. In den Gesamtdaten waren die Effekte nach kontralateraler Injektion oft signifikant größer als nach ipsilateraler Injektion. Ebenso waren die Effekte in der 2f1-f2 Emission meist signifikant größer als in der f2-f1 Emission. Zudem wurde beobachtet, dass signifikant größere Effekte bei einer Stimulation mit Pegeln von 60/50 dB SPL im Vergleich zu 40/30 dB SPL erreicht wurden. Grundsätzlich trat in allen Datensätzen eine Reversibilität der DPOAE-Pegel mit zunehmender Versuchsdauer auf. Die Effekte waren direkt nach der Injektion am größten und erreichten je nach Stimuluspegel und Emissionstyp nach 28-100 min die Basispegel. In keinem der Datensätze lag eine Abhängigkeit der im Kortex gereizten charakteristischen Frequenz (CF) zum betroffenen Frequenzbereich in der Kochlea vor. Die Effekte waren über den gesamten gemessenen Frequenzbereich von 1-40 kHz nachweisbar. Allerdings waren die Frequenzbereiche von 1-10 kHz und 30,5-40 kHz besonders stark von der Lidocaininjektion betroffen.
Auch nach der elektrischen Reizung wurden die drei oben beschriebenen Effekttypen definiert. Mit 54,6 % war der Prozentsatz unveränderter DPOAE-Pegel allerdings sehr hoch. In den anderen beiden Kategorien konnten zusätzlich Differenzierungen im zeitlichen Verhalten der DPOAE-Pegel vorgenommen werden. In 21,6 % bzw. 16,5 % der Datensätze waren die Verringerungen bzw. Erhöhungen bis zum letzten gemessenen Zeitpunkt nach der elektrischen Reizung irreversibel und nur in jeweils 2,8 % der Datensätze war eine Reversibilität zu verzeichnen. In diesen Fällen war die Effektdauer mit im Mittel 31 bzw. 25 min kürzer als in den Lidocainversuchen. Auch die Effektstärken waren mit maximal 23,9 dB und je nach Effekttyp im Mittel 5,1-13,7 dB geringer als nach der Lidocaininjektion. Die größten Effekte traten in einem mittleren Stimuluspegelbereich von 45-55 dB SPL auf. Wiederum konnte keine Abhängigkeit des betroffenen Frequenzbereichs von der kortikal gereizten CF nachgewiesen werden. In Einzelfällen waren auf DPOAE-Ebene nur die Frequenzen ober- und unterhalb der kortikalen CF beeinflusst, wohingegen bei der CF selbst keine Effekte auftraten.
Durch Kontrollexperimente (Salineinjektion bzw. Einführen der Elektrode ohne elektrische Reizung) konnte nachgewiesen werden, dass die Effekte durch die Manipulation der Kortexaktivität hervorgerufen wurden. Somit liegt eine funktionelle Beziehung zwischen dem AK und der Peripherie vor, die langanhaltende massive Ausmaße annehmen kann. Die Effektrichtung ist vermutlich durch die exzitatorisch oder inhibitorisch wirkenden Neurone vom Colliculus inferior zum Olivenkomplex bedingt. Die größeren Effekte in der kontralateralen Konfiguration lassen sich durch die Diskrepanz in der Anzahl der gekreuzten (2/3) und ungekreuzten (1/3) medialen Efferenzen erklären. Die kubischen Komponenten der äHZ-Verstärkungsfunktion scheinen stärker beeinflusst zu sein als die quadratischen Komponenten, was in größeren Pegeländerungen in der 2f1-f2 Emission resultiert. Die teils großen Effektstärken sowie die nicht vorhandene Frequenzabhängigkeit zwischen AK und Kochlea sind vermutlich auf den großen Kortexbereich zurückzuführen, der von den gewählten Injektionsvolumina bzw. elektrischen Reizstärken betroffen war. Die großen Effekte im mittleren Stimuluspegelbereich lassen sich sowohl mit einer möglichen Schutzfunktion der Efferenzen vor zu lauten Schallereignissen als auch mit einer Verbesserung des Signal-Rausch-Verhältnisses zur erleichterten Detektion akustischer Signale in Einklang bringen. Insgesamt deuten die Ergebnisse darauf hin, dass die Aktivität des AK einen starken Einfluss auf periphere auditorische Mechanismen hat, wodurch die kochleäre Verarbeitung akustischer Signale je nach kortikalem Verarbeitungsstatus massiv modifiziert werden kann.
A dozen mRNAs are edited by multiple insertions and/or deletions of uridine residues in the mitochondrion of Trypanosoma brucei. Several protein complexes have been implicated in performing this type of RNA editing, including the mitochondrial RNA-binding complex 1 (MRB1). Two paralogous novel RNA-binding proteins, MRB8170 and MRB4160, are loosely associated with the core MRB1 complex. Their roles in RNA editing and effects on target mRNAs are so far not well understood. In this study, individual-nucleotide-resolution UV-cross-linking and affinity purification (iCLAP) revealed a preferential binding of both proteins to mitochondrial mRNAs, which was positively correlated with their extent of editing. Integrating additional in vivo and in vitro data, we propose that binding of MRB8170 and/or MRB4160 onto pre-mRNA marks it for the initiation of editing and that initial binding of both proteins may facilitate the recruitment of other components of the RNA editing/processing machinery to ensure efficient editing. Surprisingly, MRB8170 also binds never-edited mRNAs, suggesting that at least this paralog has an additional role outside RNA editing to shape the mitochondrial transcriptome.
To broaden the scope of monetary policy, cash abolishment is often suggested as a means of breaking through the zero lower bound. However, practically nothing is said about the welfare costs of such a proposal. Rösl, Seitz and Tödter argue that the welfare costs of bypassing the zero lower bound can be analyzed analytically and empirically by assuming negative interest rates on cash holdings. They gauge the welfare effects of abolishing cash, both, for the euro area and for Germany.
Their findings suggest that the welfare losses of negative interest rates incurred by money holders are large, notably if implemented in the current low interest rate environment. Imposing a negative interest rate of 3 percentage points on cash holdings and reducing the interest on all assets included in M3 creates a deadweight loss of € 62bn for the euro area and of €18bn for Germany. Therefore, the authors argue that cash abolishment or negative interest rates on cash to break through the zero lower bound at any price can hardly be a meaningful policy goal.
Este trabalho pretende fazer uma síntese da inserção de Axel Honneth no quadro das teorias da justiça. Para isso, se apresenta o debate entre comunitaristas e liberais, juntamente ao procedimentalismo contemporâneo, e as críticas de Honneth a essas posições. Assim o trabalho apresenta o esboço teórico de justiça como reconhecimento em Honneth, realizado com base no conceito de eticidade formal e no método da reconstrução normativa.
Pulsed electron-electron double resonance (PELDOR), also called Double Electron-Electron Resonance, (DEER) is a pulsed EPR technique that can provide structural information of biomolecules, such as proteins or nucleic acids, complementary to other structure determination methods by measuring long distances (from 1.5 up to 10 nm) between two paramagnetic labels. Incorporation of the rigid Ç-label pairwise into DNA or RNA molecules enables the determination not only of the distance but also of the mutual orientation between the two Ç-labels by multi-frequency orientation-selective PELDOR data (X-, Q- and G-band frequencies). Thus, information about the orientation of secondary structure elements of nucleic acids can be revealed and used as additional angular information for structure determination. Since Ç does not have motion independent from the helix where it resides, the conformational flexibility of the nucleic acid molecule can be directly determined. This thesis demonstrates the advancement of PELDOR spectroscopy, beyond its original scope of distance measurements, to determine the mutual orientation between two rigid spin labels towards the characterization of the conformational space sampled by highly flexible nucleic acid molecules. Applications of the methodology are shown on two systems: a three-way junction, namely a cocaine aptamer in its bound-state, and a two-way junction, namely a bent DNA.
More in detail, the conformational changes of the cocaine aptamer upon cocaine binding were investigated by analysis of the distance distributions. The cocaine-bound and the unbound states could be differentiated by their conformational flexibility, which decreases in the presence of the ligand. Moreover, the obtained distance distributions revealed a small change in the mean distance between the two spin labels upon cocaine binding. This indicates a ligand-induced conformational change, which presumably originates at the junction where cocaine is known to bind. The investigation of the relative orientation between the two spin-labeled helices of the aptamer revealed further structural insights into the conformational dynamics of the cocaine-bound state. The angular information from the orientation-selective PELDOR data and the a priori knowledge about the secondary structure of the aptamer were helpful in obtaining a molecular model describing its global folding and flexibility. In spite of a large flexible aptamer, the kink angle between the Ç-labeled helices was found to be rather well-defined.
As for the bent DNA molecule, a two-step protocol was proposed to investigate the conformational flexibility. In the first step, a database with all the possible conformers was created, using available restraints from NMR and distance restraints derived from PELDOR. In a second step, a weighted ensemble of these conformers fitting the multi-frequency PELDOR data was built. The uniqueness of the obtained structural ensemble was checked by validation against an independent PELDOR data set recorded at a higher magnetic field strength. In addition, the kink and twist angle pairs were determined and the resulting structural ensemble was compared with the conformational space deduced both from FRET experiments and from the structure determined by the NMR restraints alone.
Overall, this thesis underlines the potential of using PELDOR spectroscopy combined with rigid spin labels in the context of structure determination of nucleic acids in order to determine the relative orientation between two helices, the conformational flexibility and the conformational changes of nucleic acid molecules upon ligand binding.
Structural and functional dissection of the DH and PH domains of oncogenic Bcr-Abl tyrosine kinase
(2017)
The two isoforms of the Bcr-Abl tyrosine kinase, p210 and p190, are associated with different leukemias and have a dramatically different signaling network, despite similar kinase activity. To provide a molecular rationale for these observations, we study the Dbl-homology (DH) and Pleckstrin-homology (PH) domains of Bcr-Abl p210, which constitute the only structural differences to p190. Here we report high-resolution structures of the DH and PH domains and characterize conformations of the DH–PH unit in solution. Our structural and functional analyses show no evidence that the DH domain acts as a guanine nucleotide exchange factor, whereas the PH domain binds to various phosphatidylinositol-phosphates. PH-domain mutants alter subcellular localization and result in decreased interactions with p210-selective interaction partners. Hence, the PH domain, but not the DH domain, plays an important role in the formation of the differential p210 and p190 Bcr-Abl signaling networks.
Diese Untersuchung beschäftigt sich mit der Morphosyntax pronominaler Partitivanaphern im kontinentalwestgermanischen Dialektkontinuum im Allgemeinen und im deutschen (insbesondere hessischen) Sprachraum im Speziellen. Schwerpunkte sind dabei die sprachgeografische Verteilung, die morphosyntaktische Variation und die strukturelle Analyse pronominaler Ausdrucksmittel der unbestimmten Teilmenge. Es werden traditionell dialektologische Erkenntnisinteressen (Raumstruktur syntaktischer Variablen und Verlauf syntaktischer Isoglossen) mit Fragestellungen der (theoretisch orientierten) Syntaxforschung verbunden. Außerdem erfolgt erstmals eine wirklich sprachübergreifende Behandlung der verschiedenen Systeme pronominaler Partitivität, zum einen innerhalb der (West-)Germania, zum anderen durch den Einbezug (zentral-)romanischer Sprachen, um Unterschiede und Gemeinsamkeiten auf der Mikro- und Mesoebene herauszuarbeiten. Die gewählte Methode ist nicht nur kontrastiv, sondern auch geolinguistisch fundiert, insofern als morphologische Formen und syntaktische Variation im Raum abgebildet werden, wodurch nicht zuletzt auch interessante Korrelationen und Anti-Korrelationen in den Daten bestätigt bzw. entdeckt werden konnten.
Nach einer Gegenstandsbestimmung der morphosyntaktischen Variable und ihrer Varianten (Inventarisierung und Typisierung) sowie des Variationsrahmens (areal-horizontal, vertikal, morphosyntaktisch, historisch, idiolektal etc.) wird zunächst das DFG-Projekt „Syntax hessischer Dialekte“ (SyHD) vorgestellt, das die empirische Basis zur Untersuchung lieferte. Dabei werden generelle und spezifische Fragen der Datengewinnung (multivariate Methode mit indirekten und direkten Elementen) sowie der Datenanalyse und -interpretation (Instrument der Kartierung) diskutiert. Den Hauptteil der Arbeit bildet die diatopische, diachrone und distributionell-syntaktische Variation der Systeme pronominaler Partitivität. Als die vier Hauptstrategien zum Ausdruck partitiv-anaphorischer Referenz innerhalb des deutschsprachigen Gebiets finden sich das konservative System versteinerter Pronominalgenitive wie „(d)(e)r(e)“, „s(e)n“ und „es“ (vor allem in einem mitteldeutschen Streifen und randdialektal) - Relikte eines ehemals umfassenderen genitivbasierten Systems der Partitivität -, das sprachgeschichtlich junge und typologisch auffällige indefinit-partitive Pronomen „welch-“/„we(l)k-“ (im Nieder-/Norddeutschen und in der Standardsprache) sowie schließlich die innovativen Systeme der Null-Anapher (im Alemannischen bzw. Südwesten) und des generalisierten Indefinitpronomens „ein-“ (im Bairischen bzw. Südosten). Wenngleich sich diese areale Distribution im zentral gelegenen und daher unter dem Einfluss nahezu aller Strategien stehenden Hessen als Kleinraum bestätigt - mit Ausnahme der weitgehenden Abwesenheit des „ein“-Systems -, so zeigen sich doch einige überraschende Ergebnisse wie beispielsweise ein kategorialer Unterschied nach Numerus und zum Teil Genus bei der Vitalität der Genitivpartikeln. Sprachhistorisch können zwei Arten von Wandel beim Genitiv-System identifiziert werden: systeminterne Veränderungen (durch Merkmals- oder Formverlust) und systemexterne Verdrängungsprozesse (durch Ausbreitung der innovativen Ausdrucksformen, was in einem Dialekt bzw. intraindividuell zu konkurrierenden oder Mischsystemen führen kann). Darüber hinaus sind mit Blick auf die Art und Weise der Veränderungen für Sprachwandelprozesse allgemein typische zyklische Abfolgen von Abschwächung und Verstärkung erkennbar. In Bezug auf die syntaktische Distribution werden insbesondere die Genitivanaphern auf ihre Kompatibilität mit nominalen Modifikatoren wie Numeralien/(schwachen) Quantoren, „flektierten“ Zahlwörtern (Schwa), Adjektiven, verschiedenen Arten von Präpositionalphrasen sowie Relativ- vs. Komplementsätzen hin untersucht und - funktional wie formal - mit ihrem niederländischen partitiven/quantitativen Äquivalent „er“ sowie den romanischen, in ein partitives System integrierten Pronomina fr. „en“/it. „ne“ verglichen. Für die deutschen Partitivanaphern ergibt sich daraus Evidenz für zwei unterschiedliche Pronominalisierungsebenen. Abschließend wird das Phänomen in die allgemeine Diskussion um nominale Ellipsen eingebettet (Elision und Pronominalisierung). Aufgrund der Evaluation der in der Literatur diskutierten Lizenzierungsansätze anhand neuer dialektaler und typologischer Daten wird hier ein flexions-/kongruenzbasierter Ansatz favorisiert (Rolle von Adjektivmorphologie bzw. generell von unterschiedlichen Flexionssystemen, etwa im Deutschen vs. Englischen).
Molecular detection of Bartonella henselae in 11 Ixodes ricinus ticks extracted from a single cat
(2017)
Background: Bartonella henselae is a highly prevalent, vector-borne pathogen. Transmission to humans and animals by ticks is discussed controversially. Here, we present a case report, where eleven Ixodes ricinus ticks all harbouring B. henselae DNA were removed from one single cat.
Results: The first feeding tick was tested positive for B. henselae DNA. The cat was also found to be seropositive for anti-B. henselae IgG antibodies (titer 1:640). Bartonella henselae was not cultivatable from cat blood. Ten more feeding ticks removed 7 months later contained also B. henselae DNA. Sequence analysis of the 16SrDNA and the 16S-23S internal transcribed spacer (ITS) region revealed 100% sequence homology between all ticks. Bartonella adhesin A (badA) and VirB/VirD4 type IV secretion system (virB) DNA were also detected in all ticks.
Conclusions: Our results indicate that cats may serve as a reservoir for adult ticks to acquire B. henselae. Whether this observation implies an increased threat for human and animal health needs to be resolved.
We aimed to prospectively assess changes in chronic stress among young adults transitioning from high school to university or working life. A population-based cohort in Munich and Dresden (Germany) was followed from age 16–18 (2002–2003) to age 20–23 (2007–2009) (n = 1688). Using the Trier Inventory for the Assessment of Chronic Stress, two dimensions of stress at university or work were assessed: work overload and work discontent. In the multiple ordinal generalized estimating equations, socio-demographics, stress outside the workplace, and job history were additionally considered. At follow-up, 52% of the population were university students. Work overload increased statistically significantly from first to second follow-up, while work discontent remained constant at the population level. Students, compared to employees, reported a larger increase in work overload (adjusted odds ratio (OR): 1.33; 95% confidence interval (95% CI): 1.07, 1.67), while work discontent did not differ between the groups. In conclusion, work overload increases when young adults transition from school to university/job life, with university students experiencing the largest increase.
Metal ions as novel polarizing agents for dynamic nuclear polarization enhanced NMR spectroscopy
(2017)
High-spin complexes of Gd(III) and Mn(II) were introduced as polarizing agents (PAs) for solid-state dynamic nuclear polarization (DNP) in 2011. This dissertation was undertaken in 2013, with the intention of exploring these PAs further. Major goals of this work were to understand their DNP mechanism(s) and explore their application in biomolecular research. This cumulative thesis details the methods, advantages, and practical implications of using high-spin PAs for MAS DNP. Data from electron paramagnetic resonance (EPR) and NMR spectroscopy are discussed for a complete understanding of DNP mechanisms.
Out of the two main mechanisms − solid effect (SE) and cross effect (CE − active under experimental conditions of solid-state DNP, commonly used nitroxide PAs evoke CE owing to their broad EPR spectra. On the other hand, DNP mechanisms evoked by high-spin metal ions seem non-trivial due to additional features (originating from spin-orbit coupling or zero field splitting) in their EPR spectra. The features of the EPR signal generally influence the shape of enhancement profiles. Therefore, the metal ion with a simpler EPR signal i.e., Gd(III) , is chosen as the starting point for the investigation of DNP mechanisms. Varying concentrations (2, 10, 20 mM) of a water-soluble and stable complex Gd-DOTA was dissolved as the PA in a glycerol-water solution of 13C,15N - urea. Field profiles of DNP enhancement on each nuclear type (1H, 13C, and 15N) establishes SE as the active DNP mechanism at the smallest PA concentration (2 mM). This confirms the theoretical predictions that narrow line width of the Gd(III) EPR signal arising from the central transition (CT, ms = -1/2 +1/2) allows for resolved SE DNP. However, that is no longer the case at higher PA concentrations of 10 and 20 mM. At higher Gd(III) concentrations, the CE mechanism contributes significantly and varies with nuclear Larmor frequency (ωn) of the concerned nuclei. The enhancement maxima shifts towards the EPR resonance as the contribution from CE increases. This shift is evident in the field profiles of 15N and 13C, whereas that of 1H is least influenced. This observation can be explained by combining theoretical estimates with the experimental data; the CE is evoked by increased dipolar coupling (Dee) – a prerequisite for CE – between neighboring Gd(III) spins as the statistical inter-spin distance shortens at elevated concentrations. This finding is important because the knowledge of active DNP mechanisms is essential for accurate interpretation of results from DNP experiments.
From the experiments on Gd-DOTA it becomes clear that concentration, inter-spin distances, and hence induced Dee are intertwined. In order to explicitly address the influence of inter-spin distances on DNP mechanisms we started a collaboration with the group of Adelheid Godt (Bielefeld). In this collaborative project, bis-complexes of the type Gd(III)-spacer-Gd(III) with variable spacer lengths were investigated. These PAs provided an excellent model system where the influence of only inter-spin distances can be determined for a fixed Gd(III) concentration. A small PA concentration of 4 mM is used to ensure absence of significant inter-molecular dipolar interactions. A mono-Gd complex of similar geometry and chemistry is taken as a reference for SE DNP.
The mono-Gd complex yields enhancements arising from SE as expected from negligible inter-molecular Dee. The contribution of CE increases as the inter-spin distances between Gd(III) ions become shorter going from 3.4 nm 2.1 nm 1.4 nm 1.2 nm due to corresponding increase in Dee. The extent of CE on ωn follows the same trend as for Gd-DOTA. Highest CE contribution is observed on nuclei with the smallest ωn 15N because smaller ωn approaches the width of the EPR signal, this is an additional requirement for CE DNP.
The field position for maximum DNP enhancement corresponding to Gd-DOTA, is used for DNP experiments on Ubiquitin with an attached Gd-tag as PA. The success of DNP on this sample illustrates the possibility of site-directed DNP with metal ions tags as PAs. As a perspective Gd-tags can be used to examine change in conformation of a protein that would give higher enhancements due to CE if two Gd(III) labeled domains are closer in space. In a separate project, Mn(II) (s=5/2) bound to the divalent site of a hammerhead ribozyme was used as a PA which resulted in the first demonstration of intra-complex DNP using an intrinsically bound metal ion PA.
Im Jahr 2015 wurden im Segment "Kinder- und Jugendliteratur" 9081 Novitäten – die Zahl versteht sich ohne Neuauflagen – auf den Buchmarkt gebracht. Mehr neue Bücher für Kinder und Jugendliche gab es in der gesamten Geschichte des Buchdrucks noch nie! Ganz von allein stellt sich da die Frage, wie denn all diese Bücher ihre LeserInnen finden werden. Oder im Umkehrschluss, wie gelingt es LeserInnen, in diesem Riesenangebot die passende Lektüre zu entdecken? Entsprechend dieser Problematik lauten die Schlüsselwörter: Literaturvermittlung, (außerschulische) Förderung und Austausch. ...
Background: Modulation of cortical excitability by transcranial magnetic stimulation (TMS) is used for investigating human brain functions. A common observation is the high variability of long-term depression (LTD)-like changes in human (motor) cortex excitability. This study aimed at analyzing the response subgroup distribution after paired continuous theta burst stimulation (cTBS) as a basis for subject selection.
Methods: The effects of paired cTBS using 80% active motor threshold (AMT) in 31 healthy volunteers were assessed at the primary motor cortex (M1) corresponding to the representation of the first dorsal interosseous (FDI) muscle of the left hand, before and up to 50 min after plasticity induction. The changes in motor evoked potentials (MEPs) were analyzed using machine-learning derived methods implemented as Gaussian mixture modeling (GMM) and computed ABC analysis.
Results: The probability density distribution of the MEP changes from baseline was tri-modal, showing a clear separation at 80.9%. Subjects displaying at least this degree of LTD-like changes were n = 6 responders. By contrast, n = 7 subjects displayed a paradox response with increase in MEP. Reassessment using ABC analysis as alternative approach led to the same n = 6 subjects as a distinct category.
Conclusion: Depressive effects of paired cTBS using 80% AMT endure at least 50 min, however, only in a small subgroup of healthy subjects. Hence, plasticity induction by paired cTBS might not reflect a general mechanism in human motor cortex excitability. A mathematically supported criterion is proposed to select responders for enrolment in assessments of human brain functional networks using virtual brain lesions.
his articles discusses and contextualises tripleC's republication of Franz L. Neumann's essay Anxiety and Politics. It provides some background information on Neumann's life and works. The essay ascertains that in the age of new nationalisms, rising right-wing authoritarianism and authoritarian capitalism, Franz L Neumann's works can help us to critically understand contemporary society.
Wie verhalten sich Freiheit und Geld zueinander? In der liberalen Tradition der Philosophie und der Ökonomik wird Geld meist als bloßes Mittel gefasst, dessen Einführung den Austausch von Waren erleichtert, darüber hinaus jedoch keine tiefergreifenden sozialen Folgen zeitigt. Im Gegensatz hierzu wird in diesem Working Paper der Zusammenhang von Geld und (Un-)Freiheit herausgearbeitet. Im Anschluss an die Tradition kritischer Sozialphilosophie und in Auseinandersetzung mit Marx, Simmel und der neueren Geldsoziologie wird dabei in einem ersten Schritt der paradoxe Charakter dieser gesellschaftlich eröffneten Freiheit dargelegt: Zum einen kultiviert Geld in kapitalistischen Ökonomien eine individuelle Form von Wahlfreiheit. Zum anderen wird über Geld der Zugang zum gesellschaftlichen Reichtum auf ungleiche und disziplinierende Weise strukturiert: Je nach individueller Verfügung über finanzielle Mittel ist man auf unterschiedliche Weise zum Verkauf der eigenen Arbeitskraft angehalten, um den Zugriff auf Güter und die eigene Reproduktion zu sichern. Diese paradoxe Form von Freiheit wird in einem zweiten Schritt hinsichtlich ihrer Entfremdungstendenz befragt: Insofern die über die Institution des Geldes eröffnete Freiheit ihren gesellschaftlichen Ermöglichungsgrund verdeckt, kann sie als eine fetischisierte Form von Freiheit begriffen werden.
Auf Grundlage einer interviewbasierten Studie zu heterosexuellen Paaren, in denen die Frau das Haupteinkommen verdient, beschäftigt sich der Beitrag mit milieuspezifischen Bewältigungsmustern prekärer Beschäftigungsverhältnisse. Vor dem Hintergrund der Erosion des Ernährermodells werden dabei Transformationen von Männlichkeit in den Blick genommen. Es wird die These entwickelt, dass sich mit dem Selbstverständnis als "Künstler" im hochqualifizierten individualisierten Milieu des urbanen Raums ein spezifisches Bewältigungsmuster von Prekarität herausgebildet hat.
In dieser Dissertation wurde die Rolle des Proteins Carboxypeptidase E (CPE) im Glioblastom (GBM) untersucht. Ursprünglich wurde CPE in der neuroendokrinen Regulation beschrieben, wo es die Reifung der meisten Neuropeptide und Hormone reguliert und somit Einfluss auf Stoffwechsel und humorale Effekte hat (Fricker et al., 1982; Fricker & Snyder, 1982 and 1983; Davidson & Hutton, 1987; Shen & Loh, 1997; Lou et al., 2005). Ab 1989 wurde CPE in unterschiedlichen Tumorentitäten nachgewiesen (Grimwood et al., 1989; Manser et al., 1991), jedoch ohne Hinweise, welche Bedeutung das Protein dort haben könnte. Erst im letzten Jahrzehnt konnten sowohl pro- als auch anti-tumorigene Wirkungen von CPE gezeigt werden. Die beschriebenen Wirkungen von CPE sind jedoch von dessen Isoform abhängig. Das ∂(delta)N-trunkierte CPE zeigte sich mit erhöhtem Tumorwachstum und schlechter Überlebensprognose in verschiedenen Krebsentitäten assoziiert (Murthy et al., 2010; Lee et al., 2011; Zhou et al., 2013). Im Gegensatz dazu verringerte sezerniertes CPE (sCPE) im Fibrosarkom und Glioblastom die Zellmigration, was einen anti-tumorigenen Effekt suggeriert (Höring et al., 2012; Murthy et al., 2013a). Die Molekularmechanismen, die für die Regulation der Migration zuständig sind, sind jedoch kaum untersucht. Die meisten Untersuchungen von sCPE in Normal- und Tumorgewebe beschränken sich hauptsächlich auf Apoptose und Zellüberleben (Skalka et al., 2013; Murthy et al., 2013b; Cheng et al., 2013; Selvaraj et al., 2015; Cheng et al., 2015). Die vorliegende Arbeit ist demzufolge die erste Studie, die sich dem Mechanismus der Migrationsregulation durch sCPE im Glioblastom widmet.
Humane Gliome stellen die größte und bösartigste Gruppe hirneigener Tumore dar. Bösartige Gliome sind höchst resistent gegen alle zurzeit verfügbaren Behandlungsmethoden. Einer der Hauptgründe dafür ist, dass die Tumorzellen durch diffuse Infiltration in das Gehirn einwandern können. Ferner sind Gliomzellen metabolisch sehr aktiv und können sich dadurch an schnell verändertes Milieu anpassen (Fack et al., 2015; Demeure et al., 2016). Über die grundlegenden Mechanismen für diese Art des infiltrierenden Tumorwachstums ist bisher noch nicht viel bekannt. Zurzeit sind nur wenige Schlüsselfaktoren beschrieben, die den sogenannten Mechanismus der Migration oder Proliferation ("go or grow") in bösartigen Tumoren beeinflussen: wenige Transkriptionsfaktoren, miRNAs sowie metabolische Faktoren. Interessanterweise, sind miRNAs zum Teil mit der Regulation des Metabolismus in Tumorzellen assoziiert. Eine vorangehende Studie aus unserem Labor hat sCPE aufgrund seines Potentials, Zellwanderung zu verringern, als einen weiteren Schlüsselfaktor identifiziert. Wir konnten zeigen, dass sCPE in der Gliomzelllinie LNT-229 zur einer differentiellen Regulation von Migration und Proliferation führt (Höring et al., 2012). Die vorliegende Arbeit widmet sich nun der Frage nach den genauen zugrundeliegenden Mechanismen, wie sCPE seine Effekte auf molekularer Ebene vermittelt. Darüber hinaus soll geklärt werden, ob sCPE auch in der metabolischen Adaptation eine Rolle spielt und dadurch ebenfalls die Gliomzellmigration beeinflußen kann.
Binding free energy calculations that make use of alchemical pathways are becoming increasingly feasible thanks to advances in hardware and algorithms. Although relative binding free energy (RBFE) calculations are starting to find widespread use, absolute binding free energy (ABFE) calculations are still being explored mainly in academic settings due to the high computational requirements and still uncertain predictive value. However, in some drug design scenarios, RBFE calculations are not applicable and ABFE calculations could provide an alternative. Computationally cheaper end-point calculations in implicit solvent, such as molecular mechanics Poisson–Boltzmann surface area (MMPBSA) calculations, could too be used if one is primarily interested in a relative ranking of affinities. Here, we compare MMPBSA calculations to previously performed absolute alchemical free energy calculations in their ability to correlate with experimental binding free energies for three sets of bromodomain–inhibitor pairs. Different MMPBSA approaches have been considered, including a standard single-trajectory protocol, a protocol that includes a binding entropy estimate, and protocols that take into account the ligand hydration shell. Despite the improvements observed with the latter two MMPBSA approaches, ABFE calculations were found to be overall superior in obtaining correlation with experimental affinities for the test cases considered. A difference in weighted average Pearson () and Spearman () correlations of 0.25 and 0.31 was observed when using a standard single-trajectory MMPBSA setup ( = 0.64 and = 0.66 for ABFE; = 0.39 and = 0.35 for MMPBSA). The best performing MMPBSA protocols returned weighted average Pearson and Spearman correlations that were about 0.1 inferior to ABFE calculations: = 0.55 and = 0.56 when including an entropy estimate, and = 0.53 and = 0.55 when including explicit water molecules. Overall, the study suggests that ABFE calculations are indeed the more accurate approach, yet there is also value in MMPBSA calculations considering the lower compute requirements, and if agreement to experimental affinities in absolute terms is not of interest. Moreover, for the specific protein–ligand systems considered in this study, we find that including an explicit ligand hydration shell or a binding entropy estimate in the MMPBSA calculations resulted in significant performance improvements at a negligible computational cost.
Transition path sampling is a powerful tool in the study of rare events. Shooting trial trajectories from configurations along existing transition paths proved particularly efficient in the sampling of reactive trajectories. However, most shooting attempts tend not to result in transition paths, in particular in cases where the transition dynamics has diffusive character. To overcome the resulting efficiency problem, we developed an algorithm for “shooting from the top.” We first define a shooting range through which all paths have to pass and then shoot off trial trajectories only from within this range. For a well chosen shooting range, nearly every shot is successful, resulting in an accepted transition path. To deal with multiple mechanisms, weighted shooting ranges can be used. To cope with the problem of unsuitably placed shooting ranges, we developed an algorithm that iteratively improves the location of the shooting range. The transition path sampling procedure is illustrated for models of diffusive and Langevin dynamics. The method should be particularly useful in cases where the transition paths are long so that only relatively few shots are possible, yet reasonable order parameters are known.
Rechtspopulistische Bewegungen machen sich zur Zeit in vielen westlichen Staaten zum Sprachrohr angeblich bisher unterdrückter Bevölkerungsgruppen und Meinungen. Die identitäre Bewegung entwickelt diesen Ansatz weiter zu einem Projekt der autoritären Staatlichkeit gegen Multikulturalismus, Islam und Einwanderung. Dabei verbindet sie ihre Kampagne für einen ethnisch geschlossen Nationalstaat mit der Kritik an der kapitalistischen Globalisierung. Mit einem Sprachduktus, der Politik emotionalisiert, wird durch «geistige Verschärfung» das Programm eines defensiven Ethnonationalismus entfaltet. Dieser beruft sich auf Traditionsbestandteile eines völkischen Antimodernismus und eine von dem russischen Philosophen Alexander Dugin entworfene eurasische Geopolitik.
Ein europäischer Keynesianismus als Grundlage für ein gesamteuropäisches Wirtschaftskonzept würde als offensive Gegenstrategie die Idee einer sozialstaatlichen Erneuerung propagieren können. Zudem sind Akteure aus der Zivilgesellschaft aufgefordert, gegen Fremdenfeindlichkeit und Orientierungsverlust aufklärerisch zu wirken.
WiWi news ; Nr. 1 [2017]
(2017)
The turnover of endoplasmic reticulum (ER) ensures the correct biological activity of its distinct domains. In mammalian cells, the ER is degraded via a selective autophagy pathway (ER-phagy), mediated by two specific receptors: FAM134B, responsible for the turnover of ER sheets and SEC62 that regulates ER recovery following stress. Here, we identified reticulon 3 (RTN3) as a specific receptor for the degradation of ER tubules. Oligomerization of the long isoform of RTN3 is sufficient to trigger fragmentation of ER tubules. The long N-terminal region of RTN3 contains several newly identified LC3-interacting regions (LIR). Binding to LC3s/GABARAPs is essential for the fragmentation of ER tubules and their delivery to lysosomes. RTN3-mediated ER-phagy requires conventional autophagy components, but is independent of FAM134B. None of the other reticulon family members have the ability to induce fragmentation of ER tubules during starvation. Therefore, we assign a unique function to RTN3 during autophagy.
Human immunodeficiency virus type 1 (HIV-1) infection of dividing and nondividing cells involves regulatory interactions with the nuclear pore complex (NPC), followed by translocation to the nucleus and preferential integration into genomic areas in proximity to the inner nuclear membrane (INM). To identify host proteins that may contribute to these processes, we performed an overexpression screen of known membrane-associated NE proteins. We found that the integral transmembrane proteins SUN1/UNC84A and SUN2/UNC84B are potent or modest inhibitors of HIV-1 infection, respectively, and that suppression corresponds to defects in the accumulation of viral cDNA in the nucleus. While laboratory strains (HIV-1NL4.3 and HIV-1IIIB) are sensitive to SUN1-mediated inhibition, the transmitted founder viruses RHPA and ZM247 are largely resistant. Using chimeric viruses, we identified the HIV-1 capsid (CA) protein as a major determinant of sensitivity to SUN1, and in vitro-assembled capsid-nucleocapsid (CANC) nanotubes captured SUN1 and SUN2 from cell lysates. Finally, we generated SUN1−/− and SUN2−/− cells by using CRISPR/Cas9 and found that the loss of SUN1 had no effect on HIV-1 infectivity, whereas the loss of SUN2 had a modest suppressive effect. Taken together, these observations suggest that SUN1 and SUN2 may function redundantly to modulate postentry, nuclear-associated steps of HIV-1 infection.
IMPORTANCE HIV-1 causes more than 1 million deaths per year. The life cycle of HIV-1 has been studied extensively, yet important steps that occur between viral capsid release into the cytoplasm and the expression of viral genes remain elusive. We propose here that the INM components SUN1 and SUN2, two members of the linker of nucleoskeleton and cytoskeleton (LINC) complex, may interact with incoming HIV-1 replication complexes and affect key steps of infection. While overexpression of these proteins reduces HIV-1 infection, disruption of the individual SUN2 and SUN1 genes leads to a mild reduction or no effect on infectivity, respectively. We speculate that SUN1/SUN2 may function redundantly in early HIV-1 infection steps and therefore influence HIV-1 replication and pathogenesis.
Reticulate evolution is considered to be among the main mechanisms of plant evolution, often leading to the establishment of new species. However, complex evolutionary scenarios result in a challenging definition of evolutionary and taxonomic units. In this study, we aimed to examine the evolutionary origin and revise the species status of Campanula baumgartenii, a rare endemic species from the polyploid complex Campanula section Heterophylla. Morphometry, flow cytometric ploidy estimation, amplified fragment length polymorphisms (AFLPs), as well as chloroplast and nuclear DNA sequence markers were used to assess the morphological and genetic differentiation among C. baumgartenii, Campanula rotundifolia and other closely related taxa. Tetra- and hexaploid C. baumgartenii is morphologically and molecularly (AFLP) differentiated from sympatric C. rotundifolia. Contrasting signals from nuclear (ITS) and chloroplast (trnL-rpl32) markers suggest a hybrid origin of C. baumgartenii with C. rotundifolia and a taxon related to the alpine Campanula scheuchzeri as ancestors. Additionally, hexaploid C. baumgartenii currently hybridizes with co-occurring tetraploid C. rotundifolia resulting in pentaploid hybrids, for which C. baumgartenii serves as both seed and pollen donor. Based on the molecular and morphological differentiation, we propose to keep C. baumgartenii as a separate species. This study exemplifies that detailed population genetic studies can provide a solid basis for taxonomic delimitation within Campanula section Heterophylla as well as for sound identification of conservation targets.
In 2006, the Task Force of the European Society of Cardiology published its consensus document on the use of autologous cell therapy for repair of the heart. Since then, there have been numerous clinical trials and analyses performed to establish the role of autologous cell therapy in the treatment of both acute and chronic cardiac disease. The majority of these studies have been Phase II clinical trials. Phase III clinical trials of autologous cell therapy have been launched (e.g. BAMI), which marks the successful progression of clinical investigation of autologous cell therapy in heart disease. The Task Force has reviewed its 2006 recommendations and the developments in this area of research and proposes updated recommendations for the future of autologous cell therapy in the heart. This article does not duplicate the many reviews on stem cells and the heart but gives considered recommendations based on the experience from the last 10 years.
Eiskeime (INP) sind Aerosolpartikel, die das Entstehen von Eiskristallen in der Atmosphäre zwischen 0 und -37°C ermöglichen, indem sie die zur Ausbildung der Eisphase nötige Energie gegenüber einem reinen Wassersystem stark herabsetzen. Dabei sind aktive Stellen auf der Oberfläche dieser Partikel für die erste Nukleation von Eis verantwortlich. In der Folge können die Eiskristalle zulasten von verdunstenden Wasserdampfmolekülen und Wassertröpfchen weiter anwachsen. Über Eismultiplikationsprozesse zersplittern und vervielfältigen sich die Eiskristalle und wachsen über Bereifung schließlich zu einer kritischen Größe heran, wodurch sie als Niederschlag zu Boden fallen können. Auch wenn der Anteil der zur heterogenen Eisnukleation fähigen Aerosole vergleichsweise gering ist, spielen INP eine entscheidende Rolle für die Entwicklung von Niederschlag und nehmen Einfluss auf Strahlungsprozesse, indem sie auf die Phase der Wolken und damit auf deren Strahlungseigenschaften einwirken. Viele Fragen im Forschungsgebiet der heterogenen Eisnukleation sind jedoch weiterhin nicht hinreichend genau geklärt. Ohne eine verbesserte Kenntnis von Konzentrationen, geographischer und vertikaler Verteilung, sowie zeitlicher Variation, Quellen und Natur von INP, sind noch vorhandene Wissenslücken im Strahlungsantrieb durch Wechselwirkungen von Aerosolen und Wolken nur zu einem gewissem Grad zu reduzieren. Dies ist nötig, um aktuelle Beobachtungsdaten der sich erwärmenden Atmosphäre besser verstehen und die zukünftigen Änderungen des Klimas sicherer vorhersagen zu können. In dieser Arbeit wird die Vakuumdiffusionskammer FRIDGE verwendet, um atmosphärische INP-Konzentrationen zu bestimmen. Aerosolpartikel werden dabei in einem ersten Schritt auf einem Silicium-Probenträger elektrostatisch niedergeschlagen. Die Effizienz des Sammelprozesses, also der Anteil der Partikel die tatsächlich auf dem Si-Substrat abgeschieden werden, wurde mittels zweier unabhängiger Methoden auf etwa 60% bestimmt. In einem zweiten Mess-Schritt werden die Proben in FRIDGE typischen Bedingungen von Mischphasenwolken ausgesetzt, wodurch Eiskristalle an den INP aktiviert werden und im Verlauf einer Messung anwachsen. Eine Kamera beobachtet die durch das Eiswachstum entstehenden Helligkeitsänderungen auf dem dunklen Probensubstrat. Die Kriterien, wann ein Objekt als Eiskristall identifiziert und gezählt wird, mussten im Rahmen dieser Arbeit neu entwickelt werden. In der zu Beginn der Arbeit vorgefundenen Einstellung hatte bereits eine sehr geringe Helligkeitsänderung, wie sie durch das hygroskopische Wachstum von Aerosolpartikeln hervorgerufen wird, zu Signalen geführt, die fälschlicherweise als Eiskristalle gezählt wurden. Das reevaluierte Messverfahren von FRIDGE wurde im Zuge der FIN-02 Kampagne in einem groß angelegten Laborexperiment an der AIDA Wolkenkammer mit zahlreichen anderen INP-Zählern aus der ganzen Welt verglichen. Für den Großteil der Messungen der untersuchten Modell-Aerosoltypen konnte eine zufriedenstellende Übereinstimmung mit den anderen Instrumenten erzielt werden. In einer einmonatigen Feldmesskampagne im östlichen Mittelmeerraum konnten die ersten INP-Messungen an Bord eines unbemannten Flugzeugs durchgeführt werden. Während der Kampagne auf Zypern wurden mehrere Fälle von transportiertem Saharastaub beprobt, in denen die INP-Konzentration maßgeblich erhöht war. Lidar-Beobachtungen und ein Staubtransportmodell zeigten, dass sich das Maximum der Staubschichten zumeist in etwa 2-4 Kilometern Höhe befand. In der Höhe wurden INP-Konzentrationen gefunden, die im Mittel um einen Faktor 10 größer waren als auf Bodenniveau. Es wird gefolgert, dass INP-Messungen am Boden möglicherweise nur begrenzte Aussagekraft über die Situation nahe der Wolkenbildung besitzen. Im Rahmen BACCHUS-Projekts wurden zwischen August 2014 und Januar 2017 (mit Unterbrechungen) alle 1-2 Tage Proben an drei Reinluftstationen gesammelt (insgesamt über 900). Das INP-Messnetz mit einer geographischen Ausdehnung von der Arktis zum Äquator bestand aus Stationen in Spitzbergen, Martinique und im Amazonas. Die Station im brasilianischen Regenwald ist durch wechselnde Bedingungen von sauberer Regen- und verunreinigter Trockenzeit charakterisiert. In der Trockenzeit steigen die Partikelkonzentrationen durch starke Belastung aus Biomassenverbrennung um eine Größenordnung an; eine gleichzeitige Zunahme der INP-Konzentrationen konnte nicht beobachtet werden. Daraus kann vermutet werden, dass Partikel aus Feueremissionen keine ausgezeichneten Fähigkeiten zur Eisnukleation aufweisen. Die INP-Konzentrationen in der Karibik konnten mit dem Jahresgang von transportieren Saharastaub in Verbindung gebracht werden. In der Arktis wurden die niedrigsten INP-Konzentrationen der drei Stationen beobachtet. Zum Zeitpunkt des Erstellens dieser Arbeit können die determinierenden Einflussfaktoren, sowie der anthropogene Einfluss zur Zeit des arktischen Dunstes noch nicht abschließend geklärt werden.
There is a consensus that transnational soft governance has unleashed the forces of change in higher education. However, individual national HE systems are still anchored in country-specific regulatory regimes, which reflect national-historical, institutional, and cultural developments. Against this background, three crucial questions guide our study: How does the state react to transnational pressures for change? How is transnationally inspired policy change ‘digested’ by the preexisting country-specific governance structures? And to what extent have national HE systems converged on a common governance model? To address these questions, we conduct a multilevel comparative analysis of developments in Germany, France, and Italy. We first break down the concept of higher education governance into sub-dimensions and derive concrete policy indicators for three historically embedded governance ideal types. Drawing on historical institutionalism and institutional isomorphism, we explore how historical legacies and transnational communication have impacted policy pathways over the past 30 years. We graphically illustrate the policy trajectories using our ‘governance triangles’, which encompass the balance of power between multiple actors, including the state and universities, university management and the academic profession, and external stakeholders.
The physical housing environment is important to facilitate activities of daily living (ADL) for older people. A hindering environment may lead to ADL dependence and thus increase the need for home services, which is individually restricting and a growing societal burden. This study presents simulations of policy changes with regard to housing accessibility that estimates the potential impact specifically on instrumental activities of daily living (I-ADL), usage of home services, and related costs. The models integrate empirical data to test the hypothesis that a policy providing funding to remove the five most severe environmental barriers in the homes of older people who are at risk of developing dependence in I-ADL, can maintain independence and reduce the need for home services. In addition to official statistics from state agencies in Sweden and Germany, we utilized published results from the ENABLE-AGE and other scientific studies to generate the simulations. The simulations predicted that new policies that remove potentially hindering housing features would improve I-ADL performance among older people and reduce the need for home services. Our findings suggest that a policy change can contribute to positive effects with regard to I-ADL independence among older people and to a reduction of societal burden.
This article reports the results of a replication of Bobbitt-Zeher’s 2007 article "The Gender Income Gap and the Role of Education". Models that emulate the original specifications (by and large) reproduce the original results. However, models that adhere to Bobbitt-Zeher’s theory concerning the gendered effect of family formation call into question her finding that "values appear to matter only modestly, while family formation has virtually no effect on the income gap".
Daniel Stein und Jan-Noël Thon rücken in ihrem Sammelband die Theorie und Geschichte graphischer Narrative ("Graphic Narrative") in den Untersuchungsfokus, mit dem Ziel "[to] examine some of the more salient contexts and their effects on specific narrative affordances and limitations, conventions and innovations" (8). Dass sie dabei eine enorme Vielfalt an Gegenständen, über die auch keinesfalls Eindeutigkeit herrscht, aufrufen, deutet der Haupttitel bereits an: Vom Comic Strip bis zur Graphic Novel gibt es ein weites Spektrum an möglichen Formen des graphischen Erzählens, wobei etwa das Bilderbuch in den Studien noch gar nicht berücksichtigt worden ist. ...
Ein Dialog zwischen Sohn und Vater: "Wovon handeln Bücher eigentlich?" – "Alle wichtigen Bücher handeln von Gott." So beschreibt es Guus Kuijer in Das Buch von allen Dingen (2006). Mit dieser Geschichte beginnt der vorliegende Band über religiöse Spuren in aktueller Kinder- und Jugendliteratur, der die vier Vorlesungen des Kontaktstudiums der Theologischen Fakultät Fulda im Sommersemester 2015 unter dem Dictum versammelt: "Alle wichtigen Bücher handeln von Gott." (vgl. 7) Georg Langenhorst fundiert die religionspädagogische Auseinandersetzung mit Kinder- und Jugendliteratur in "Gestatten: Gott! Religion in der Kinder- und Jugendliteratur unserer Zeit. Befund, Deutung und Perspektiven für religiöses Lernen" (11–65) mit einer Analyse des aktuellen Jugendbuchmarktes. ...
Mit unterschiedlicher Schwerpunktsetzung untersuchen die drei Sammelbände elementare Grundbausteine von Serialität – Wiederholung, Schema und Variation des Schemas: Seriality in Texts for Young People konzentriert sich auf den Aspekt von Wiederholung (repetition) und fokussiert dabei strukturelle und poetologische Aspekte. An unterschiedlichsten Beispielen, über Lucy Maud Montgomerys Anne-Serie (Laura M. Robinson) bis hin zu Buffy the Vampire Slayer (Debra Dudek), wird dabei aufgezeigt, wie das Prinzip Wiederholung genutzt und unterlaufen wird, welche technischen (etwa zum MP3-Format, Larissa Wodtke), erziehungstechnischen (etwa Michelle J. Smith über das Viktorianische School Paper) und erzähltechnischen Mittel mit welchem Ergebnis eingesetzt werden. ...
Der Band Erich Kästners literarische Welten und ihre Verfilmungen schließt die zwölfbändige Reihe Bilder erzählen Geschichten – Geschichten erzählen zu Bildern, die von Karin Richter und Burkhard Fuhs seit 2006 herausgegeben wird, ab. Im Zentrum stehen mit Emil und die Detektive (1929) und Die Konferenz der Tiere (1949) zwei kinderliterarische Texte Erich Kästners, die auch verfilmt wurden und die im Hinblick auf Erich Kästners Leben und Werk in größeren, fächerübergreifenden Unterrichtsprojekten u. a zum Aufbau des Geschichtsverständnisses bei jüngeren Kindern herangezogen werden sollen (vgl. 116f. und Kapitel 1). ...
Unter dem Titel Kästner im Spiegel erscheinen aus Anlass des 40. Todestages von Erich Kästner im Jahr 2014 fünfzehn neue Beiträge zur Kästner-Forschung, herausgegeben von Sebastian Schmideler und Johan Zonneveld. Die Herausgeber, beide ausgewiesene Kästner-Kenner, fragen danach, ob und wie sich Kästner heute noch in der literaturwissenschaftlichen Diskussion spiegelt bzw. welche Spuren, Wirkungen und Erkenntnisse zu seinem Werk in der aktuellen Forschung zu finden sind. ...
Die zunehmende gesellschaftliche Aufmerksamkeit für Behinderung und Inklusion spiegelt sich im aktuellen literaturwissenschaftlichen und didaktischen Interesse am kinder- und jugendliterarischen Umgang mit Behinderung und Krankheit. Die Grenzen zwischen Erzählungen von Krankheit und Behinderung sind dabei bisweilen fließend, so dass bereits der Versuch, entsprechende Phänomene begrifflich mit Termini wie Krankheitsnarrativ, Abweichungsnarrativ oder Sick-Lit zu fassen, zum Ansatzpunkt der Forschung wird – wie auch in den hier vorgestellten Publikationen.
Zika virus (ZIKV) infection, a public health emergency of international concern, has recently been confirmed in Indonesia. However, to date, there has been no study to assess how prepared healthcare workers in Indonesia are to confront this emerging infectious disease. The aim of this study was to assess the attitudes of medical doctors in Indonesia towards ZIKV infection and its associated explanatory variables. A cross-sectional self-administered online survey was conducted from 3 May to 3 June 2016 in Aceh province, Indonesia. A pre-tested questionnaire was used to collect data on doctors’ attitudes towards ZIKV infection and a range of explanatory variables (basic demographic data, professional characteristics, workplace characteristics and facilities, and medical experience related to ZIKV infection). Associations between attitude and explanatory variables were assessed using multiple-step logistic regression. We received 631 responses, 424 (67.19%) of which were included in the final analysis. Approximately 64% (271) of doctors had a poor attitude towards ZIKV infection. Experience considering ZIKV infection as a differential diagnosis and attendance at a national conference was associated with a good attitude, with odds ratios (OR) of 3.93 (95% confidence interval [CI]: 1.15–13.49) and 1.69 (95% CI: 1.03–2.76), respectively. Unexpectedly, doctors who had attended an international conference and those working at places that had molecular diagnostic (polymerase chain reaction based testing) facilities had lower odds of having a good attitude (OR: 0.35 [95% CI: 0.15–0.84] and 0.42 [95% CI: 0.19–0.95], respectively). In conclusion, the attitude towards ZIKV infection is relatively poor among doctors in Aceh. Therefore, strategies for enhancing their capacity to respond to ZIKV infection are needed. The survey concept and tools were well accepted by the participants of this study, suggesting that this rapid assessment could be rolled out across the Indonesian archipelago and elsewhere to identify and regionally differentiate unmet needs of disease and outbreak preparedness.
This guideline of the German Dermatology Society primarily focuses on the diagnosis and treatment of cutaneous manifestations of Lyme borreliosis. It has received consensus from 22 German medical societies and 2 German patient organisations. It is the first part of an AWMF (Arbeitsgemeinschaft der Wissenschaftlichen Medizinischen Fachgesellschaften e.V.) interdisciplinary guideline: "Lyme Borreliosis – Diagnosis and Treatment, development stage S3".
The guideline is directed at physicians in private practices and clinics who treat Lyme borreliosis. Objectives of this guideline are recommendations for confirming a clinical diagnosis, recommendations for a stage-related laboratory diagnosis (serological detection of IgM and IgG Borrelia antibodies using the 2-tiered ELISA/immunoblot process, sensible use of molecular diagnostic and culture procedures) and recommendations for the treatment of the localised, early-stage infection (erythema migrans, erythema chronicum migrans, and borrelial lymphocytoma), the disseminated early-stage infection (multiple erythemata migrantia, flu-like symptoms) and treatment of the late-stage infection (acrodermatitis chronica atrophicans with and without neurological manifestations). In addition, an information sheet for patients containing recommendations for the prevention of Lyme borreliosis is attached to the guideline.
Background: To prevent persistent post-surgery pain, early identification of patients at high risk is a clinical need. Supervised machine-learning techniques were used to test how accurately the patients’ performance in a preoperatively performed tonic cold pain test could predict persistent post-surgery pain.
Methods: We analysed 763 patients from a cohort of 900 women who were treated for breast cancer, of whom 61 patients had developed signs of persistent pain during three yr of follow-up. Preoperatively, all patients underwent a cold pain test (immersion of the hand into a water bath at 2–4 °C). The patients rated the pain intensity using a numerical ratings scale (NRS) from 0 to 10. Supervised machine-learning techniques were used to construct a classifier that could predict patients at risk of persistent pain.
Results: Whether or not a patient rated the pain intensity at NRS=10 within less than 45 s during the cold water immersion test provided a negative predictive value of 94.4% to assign a patient to the "persistent pain" group. If NRS=10 was never reached during the cold test, the predictive value for not developing persistent pain was almost 97%. However, a low negative predictive value of 10% implied a high false positive rate.
Conclusions: Results provide a robust exclusion of persistent pain in women with an accuracy of 94.4%. Moreover, results provide further support for the hypothesis that the endogenous pain inhibitory system may play an important role in the process of pain becoming persistent.
We present a model for the autonomous learning of active binocular vision using a recently developed biome-chanical model of the human oculomotor system. The model is formulated in the Active Efficient Coding (AEC) framework, a recent generalization of classic efficient coding theories to active perception. The model simultaneously learns how to efficiently encode binocular images and how to generate accurate vergence eye movements that facilitate efficient encoding of the visual input. In order to resolve the redundancy problem arising from the actuation of the eyes through antagonistic muscle pairs, we consider the metabolic costs associated with eye movements. We show that the model successfully learns to trade off vergence accuracy against the associated metabolic costs, producing high fidelity vergence eye movements obeying Sherrington’s law of reciprocal innervation.
Despite various policy and management responses, biodiversity continues to decline worldwide. We must redouble our efforts to halt biodiversity loss. The current lack of policy action can be partly linked to an insufficient knowledge base regarding the conservation and sustainable use of biodiversity. Biodiversity research needs to incorporate both social and ecological factors to gain a deeper understanding of the interrelations between society and nature that affect biodiversity. A transdisciplinary research approach is crucial to fulfilling these requirements. It aims to produce new insights by integrating scientific and nonscientific knowledge. Several measures need to be taken to strengthen transdisciplinary social-ecological biodiversity research: Within the science community: firstly, scientists themselves must promote transdisciplinarity; secondly, the reward system for scientists must be brought into line with transdisciplinary research processes; and thirdly, academic training needs to advocate transdisciplinarity. As for research policies, research funding priorities need to be linked to large scale biodiversity policy frameworks, and funding for transdisciplinary social-ecological research on biodiversity must be increased significantly.
Patients who undergo endovascular repair of aortic aneurysms (EVAR) require life-long surveillance because complications including, in particular, endoleaks, aneurysm rupture, and graft dislocation are diagnosed in a certain share of the patient population and may occur at any time after the original procedure. Radiation exposure in patients undergoing EVAR and post-EVAR surveillance has been investigated by previous authors. Arriving at realistic exposure data is essential because radiation doses resulting from CT were shown to be not irrelevant. Efforts directed at identification of factors impacting the level of radiation exposure in both the course of the EVAR procedure and post-EVAR endovascular interventions and CTAs are warranted as potentially modifiable factors may offer opportunities to reduce the radiation. In the light of the risks found to be associated with radiation exposure and considering the findings above, those involved in EVAR and post-EVAR surveillance should aim at optimal dose management.
Correlation of lumbar lateral recess stenosis in magnetic resonance imaging and clinical symptoms
(2017)
Aim: To assess the correlation of lateral recess stenosis (LRS) of lumbar segments L4/5 and L5/S1 and the Oswestry Disability Index (ODI).
Methods: Nine hundred and twenty-seven patients with history of low back pain were included in this uncontrolled study. On magnetic resonance images (MRI) the lateral recesses (LR) at lumbar levels L4/5 and L5/S1 were evaluated and each nerve root was classified into a 4-point grading scale (Grade 0-3) as normal, not deviated, deviated or compressed. Patient symptoms and disability were assessed using ODI. The Spearman’s rank correlation coefficient was used for statistical analysis (P < 0.05).
Results: Approximately half of the LR revealed stenosis (grade 1-3; 52% at level L4/5 and 42% at level L5/S1) with 2.2% and 1.9% respectively reveal a nerve root compression. The ODI score ranged from 0%-91.11% with an arithmetic mean of 34.06% ± 16.89%. We observed a very weak statistically significant positive correlation between ODI and LRS at lumbar levels L4/5 and L5/S1, each bilaterally (L4/5 left: rho < 0.105, P < 0.01; L4/5 right: rho < 0.111, P < 0.01; L5/S1 left: rho 0.128, P < 0.01; L5/S1 right: rho < 0.157, P < 0.001).
Conclusion: Although MRI is the standard imaging tool for diagnosing lumbar spinal stenosis, this study showed only a weak correlation of LRS on MRI and clinical findings. This can be attributed to a number of reasons outlined in this study, underlining that imaging findings alone are not sufficient to establish a reliable diagnosis for patients with LRS.
Background: Ischemia-reperfusion injury (IRI) is a major challenge in liver transplantation. The mitochondrial pathway plays a pivotal role in hepatic IRI. Levosimendan, a calcium channel sensitizer, was shown to attenuate apoptosis after IRI in animal livers. The aim of this study was to investigate the effect of levosimendan on apoptosis in human hepatocytes.
Methods: Primary human hepatocytes were either exposed to hypoxia or cultured under normoxic conditions. After the hypoxic phase, reoxygenation was implemented and cells were treated with different concentrations of levosimendan (10ng/ml, 100ng/ml, 1000ng/ml). The overall metabolic activity of the cells was measured using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), and aspartate aminotransferase (AST) levels were determined in order to quantify hepatic injury. Fluorescence-activated cell sorting (FACS) analysis was applied to measure necrosis and apoptosis. Finally, Western blotting was performed to analyze apoptotic pathway proteins.
Results: Administration of levosimendan during reperfusion increases the metabolic activity of human hepatocytes and decreases AST levels. Moreover, apoptosis after IRI is reduced in treated vs. untreated hepatocytes, and levosimendan prevents down-regulation of the anti-apoptotic protein Bcl-2 as well as up-regulation of the pro-apoptotic protein BAX.
Conclusion: The present study suggests a protective effect of levosimendan on human hepatocytes. Our findings suggest that treatment with levosimendan during reperfusion attenuates apoptosis of human hepatocytes by influencing BAX and Bcl-2 levels.
The outset of Joyce’s A Portrait of the Artist as a Young Man presents a stage of life and language that is commonly evoked and, at the same time, systematically avoided in autobiographies as well as theoretical approaches to language: infancy. This textual strategy refers back to Augustine’s Confessiones, one of the most canonical autobiographies, reading it as a mainstay for an unconventional hypothesis: Rather that understanding infancy as an early stage of, or even before, language, Joyce expounds that the condition called infancy – the openness for receiving language while being unable to master it – accompanies all speech, be it childlike or eloquent. The article analyses Joyce’s text as one instance of a general paradox of autobiographical writing: initial aphasia. Setting out with birth or infancy, autobiographical texts precede articulate discourse. In Joyce, this paradox appears as starting point for a poetical – rather than theoretical – thinking about language, and language acquisition.
The African continent is regularly portrayed as an indolent space with a well-known reputation as a chaotic continent. Viewed as lacking vision, means and capacities, Africa is perceived at best as a place that is marked by a permanent status quo, stagnation, or in worst case scenarios, as a declining continent. Various references to the continent are synonymous with famine, poverty, war, etc. Such portrayals are all the more intriguing given that the continent is known for its abundant natural resources, such as timber, oil, natural gas, minerals, etc., whose reserves are, moreover, not well known both by the African people and their leaders. As a result, there is still much progress to be made in tapping into the resources in order to improve the daily lives of African citizens.
In such a context dominated by infantile carelessness throughout the continent, the interventions of actors from outside the continent are the only hopes of bringing some vitality to this continent which is cloaked in "la grande nuit – the great darkness" (Mbembé 2013). Thus during the main sequences of recent history, representing different forms of Western penetration and activity on the African continent (slavery, imperialism, colonization), all the Western world’s contributions have obviously not sufficed to boost Africa and take it out of its never ending childhood. It has remained just as passive and apathetic today as it was yesterday.
The attraction of Asian actors to the continent is even more recent. And consistent with its abovementioned indolence, Africa is seen as an easy and defenceless prey for the Korean, Japanese, Indian, Malaysian, or Chinese conquerors. In the latter case, the insatiable appetite for natural resources whose reserves are being rapidly depleted is the cornerstone of their foreign aid policy. This led China to colonize the continent, showing a preference for Pariah Regimes which held no appeal for the West, by sending an army of workers to extract those resources (Lum et al. 2009), in defiance of all national and international regulations and based on completely opaque contracts.
Although the concept of African Agency was rapidly developed in several African countries, the aim of this study was more specific to Cameroon’s mining sector in which different entrepreneurs from abroad got involved over time. The thesis investigates whether indigenous citizens took part in any way in the development of mining projects in the country. Thus, the work assesses and analyses actions and reactions initiated and undertaken by local people in the context of China’s presence within Cameroon’s mining sector to promote and advance their interests over those of foreign investors. In addition, the author has no knowledge of any other study investigating African Agency in the mining sector as a whole in Cameroon.
In conducting this study, a multi-method research framework was developed including a series of methods used to collect data and analyse concepts of African Agency associated Political Ecology as they developed within Cameroon’s mining sector. Specifically, those methods comprised quantitative research when it came to collecting data using a positivist and empirical approach constructed by deducing evidence from statistical data collected by means of the 167 questionnaire surveys administered to local inhabitants and workers randomly selected on mining sites and in riparian communities. The questionnaires helped to capture Cameroonians' perceptions of the recent phenomenon of the gradual but significant influx of international actors and precisely Chinese players in the mining sector on the one hand, and on the other hand, observational data was collected across the GVC as developed in the Betare-Oya region. As a complement to the former technique, qualitative methods helped to study and deepen understanding of human behaviour and the social world in a holistic perspective through individual interviews, focus groups, and direct observations on the ground. In addition, the spatial analysis method based on the land use classification technique served to detect changes to land use/land cover that have been brought on by mechanised mining activities undertaken in this region. The sequencing of data collected and their processing from a ground theory perspective led to the formulation and specification of Cameroon’s Ecological Agency theory.
One of the earliest steps of this work consisted in a literature review and in placing the African Agency concept in a broader context. It then led to the state of the art, specifications about research content of the work and the main theories undergirding this thesis. Before examining developments that emerged during the last decade, a historical perspective was provided to the topic in order to show how African societies started mining operations and how they dealt with foreign partners interested in their mining resources. The aim was to show that while Western imperialism presented a challenge for the sector, it did not erase local participation, even despite the constraints associated with such involvement.
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Der Gyrus dentatus ist eine anatomische Region im Hippocampus und besitzt die einzigartige Fähigkeit auch im adulten Gehirn lebenslang neue Nervenzellen zu generieren. Dieser Prozess wird als adulte Neurogenese bezeichnet, stellt eine besondere Form struktureller Plastizität dar und es wurde gezeigt, dass adult neugebildete Körnerzellen im Gyrus dentatus essentiell am Prozess des hippocampalen Lernens und der Gedächtnisausbildung beteiligt sind. Es wird vermutet, dass neue Körnerzellen aufgrund ihrer charakteristischen Eigenschaften verstärkt auf neue Informationsmuster reagieren können und darauf spezialisiert sind Muster, die eine hohe Ähnlichkeit zueinander haben zu separieren und diese Unterschiede zu kodieren. Obwohl bereits eine Vielzahl von wissenschaftlichen Studien zum Verständnis der Entwicklung und Funktion adult neugebildeter Körnerzellen beitragen konnte, bestehen immer noch Unklarheiten darin, wie sich diese neuen Nervenzellen strukturell entwickeln, wann es zu einer funktionellen Integration kommt und wie diese beiden Prozesse miteinander zusammenhängen. In den vorliegenden Arbeiten wurde die strukturelle Entwicklung und synaptische Integration adult neugebildeter Körnerzellen in das bestehende hippocampale Netzwerk der Ratte und Maus unter in vivo Bedingungen untersucht. Zur Beantwortung dieser Fragen wurden Methoden aus der Anatomie, Histologie und in vivo Elektrophysiologie kombiniert. Der Nachweis neuer Körnerzellen erfolgte entweder durch immunhistologische Färbungen gegen spezifische Marker für unreife und reife Körnerzellen, Markierungen mit Bromdesoxyuridin oder retro- bzw. adenovirale intrazerebrale Injektionen und Expression von GFP. Es wurde eine in vivo Stimulation des Tractus perforans in der anästhesierten Ratte zur Langzeitpotenzierung der Körnerzellsynapsen und anschließend eine immunhistologische Analyse der Expression von synaptischen Aktivitäts- und Plastizitätsmarkern in neugebildeten und reifen Körnerzellen nach der Stimulation durchgeführt. Zusätzlich wurden detaillierte drei-dimensionale Rekonstruktion dendritischer Bäume erstellt und dendritische Dornenfortsätze an retroviral markierten Zellen analysiert.
Die vorliegenden Daten belegen den generellen Verlauf der Entwicklung neugeborener Körnerzellen in zwei unterschiedliche Phasen: eine frühe dendritische Reifung und eine späte funktionelle und synaptische Integration. Neugeborene Körnerzellen zeigten ein rasches dendritisches Auswachsen, dass innerhalb der ersten drei bis vier Wochen abgeschlossen war. Während dieses Wachstumsprozesses passieren Dendriten nacheinander die Körnerzellschicht und anschließend die innere, mittlere und äußere Molekularschicht. Dadurch sind sie innerhalb ihrer morphologischen Entwicklungsphasen anatomisch auf spezifische präsynaptische Partner limitiert. In der wissenschaftlichen Literatur wird eine transiente kritische Phase beschrieben, in der neugeborene Körnerzellen eine starke Plastizität und sensitivere synaptische Erregbarkeit aufweisen. Obwohl die vorliegenden Resultate keine direkten Hinweise auf eine stärkere bzw. sensitivere Plastizität neugeborener Körnerzellen liefern, konnte eine Phase zwischen vier und fünf Wochen identifiziert werden, in der neue Körnerzellen einen sprunghaften Anstieg in ihrer Fähigkeit zur Expression synaptischer Aktivitätsmarker (z.B. Arc und c-fos) und Ausbildung struktureller Plastizität (Dendriten und Dornenfortsätze) zeigten. Die präsentierten Resultate machen deutlich, dass Dornenfortsätze neuer Körnerzellen nach elf Wochen eine vergleichbare Dichte, Größenverteilung und Plastizität aufzeigen, die vergleichbar mit denen vorhandener Körnerzellen sind. Die Fähigkeit zur dendritischen Plastizität nach synaptischer Aktivierung zeigten jedoch nur neugeborene Körnerzellen zwischen der vierten und fünften Woche. Diese Ergebnisse implizieren, dass die Integration neugebildeter Körnerzellen kontinuierlich verläuft und obwohl die vorliegenden Daten die Existenz einer dendritischen Plastizität und einen sprunghaften Anstieg synaptischer Plastizität in der vierten und fünften Woche belegen, wurden keine weiteren Hinweise auf eine transiente kritische Phase gefunden. Des Weiteren zeigten dendritische Bäume von gereiften adult neugeborenen und reifen Körnerzellen Unterschiede, die daraufhin deuten, dass neue Körnerzellen eine eigene Subpopulation darstellen.
Denisovite is a rare mineral occurring as aggregates of fibres typically 200–500 nm diameter. It was confirmed as a new mineral in 1984, but important facts about its chemical formula, lattice parameters, symmetry and structure have remained incompletely known since then. Recently obtained results from studies using microprobe analysis, X-ray powder diffraction (XRPD), electron crystallography, modelling and Rietveld refinement will be reported. The electron crystallography methods include transmission electron microscopy (TEM), selected-area electron diffraction (SAED), high-angle annular dark-field imaging (HAADF), high-resolution transmission electron microscopy (HRTEM), precession electron diffraction (PED) and electron diffraction tomography (EDT). A structural model of denisovite was developed from HAADF images and later completed on the basis of quasi-kinematic EDT data by ab initio structure solution using direct methods and least-squares refinement. The model was confirmed by Rietveld refinement. The lattice parameters are a = 31.024 (1), b = 19.554 (1) and c = 7.1441 (5) Å, β = 95.99 (3)°, V = 4310.1 (5) Å3 and space group P12/a1. The structure consists of three topologically distinct dreier silicate chains, viz. two xonotlite-like dreier double chains, [Si6O17]10−, and a tubular loop-branched dreier triple chain, [Si12O30]12−. The silicate chains occur between three walls of edge-sharing (Ca,Na) octahedra. The chains of silicate tetrahedra and the octahedra walls extend parallel to the z axis and form a layer parallel to (100). Water molecules and K+ cations are located at the centre of the tubular silicate chain. The latter also occupy positions close to the centres of eight-membered rings in the silicate chains. The silicate chains are geometrically constrained by neighbouring octahedra walls and present an ambiguity with respect to their z position along these walls, with displacements between neighbouring layers being either Δz = c/4 or −c/4. Such behaviour is typical for polytypic sequences and leads to disorder along [100]. In fact, the diffraction pattern does not show any sharp reflections with l odd, but continuous diffuse streaks parallel to a* instead. Only reflections with l even are sharp. The diffuse scattering is caused by (100) nanolamellae separated by stacking faults and twin boundaries. The structure can be described according to the order–disorder (OD) theory as a stacking of layers parallel to (100).
Background: Malaria remains one of the most serious infections for travellers to tropical countries. Due to the lack of harmonized guidelines a large variety of treatment regimens is used in Europe to treat severe malaria.
Methods: The European Network for Tropical Medicine and Travel Health (TropNet) conducted an 8-year, multicentre, observational study to analyse epidemiology, treatment practices and outcomes of severe malaria in its member sites across Europe. Physicians at participating TropNet centres were asked to report pseudonymized retrospective data from all patients treated at their centre for microscopically confirmed severe Plasmodium falciparum malaria according to the 2006 WHO criteria.
Results: From 2006 to 2014 a total of 185 patients with severe malaria treated in 12 European countries were included. Three patients died, resulting in a 28-day survival rate of 98.4%. The majority of infections were acquired in West Africa (109/185, 59%). The proportion of patients treated with intravenous artesunate increased from 27% in 2006 to 60% in 2013. Altogether, 56 different combinations of intravenous and oral drugs were used across 28 study centres. The risk of acute renal failure (36 vs 17% p = 0.04) or cerebral malaria (54 vs 20%, p = 0.001) was significantly higher in patients ≥60 years than in younger patients. Respiratory distress with the need for mechanical ventilation was significantly associated with the risk of death in the study population (13 vs 0%, p = 0.001). Post-artemisinin delayed haemolysis was reported in 19/70 (27%) patients treated with intravenous artesunate.
Conclusion: The majority of patients with severe malaria in this study were tourists or migrants acquiring the infection in West Africa. Intravenous artesunate is increasingly used for treatment of severe malaria in many European treatment centres and can be given safely to European patients with severe malaria. Patients treated with intravenous artesunate should be followed up to detect and manage late haemolytic events.
Background: In oldest-old patients (>80), few trials showed efficacy of treating hypertension and they included mostly the healthiest elderly. The resulting lack of knowledge has led to inconsistent guidelines, mainly based on systolic blood pressure (SBP), cardiovascular disease (CVD) but not on frailty despite the high prevalence in oldest-old. This may lead to variation how General Practitioners (GPs) treat hypertension. Our aim was to investigate treatment variation of GPs in oldest-olds across countries and to identify the role of frailty in that decision.
Methods: Using a survey, we compared treatment decisions in cases of oldest-old varying in SBP, CVD, and frailty. GPs were asked if they would start antihypertensive treatment in each case. In 2016, we invited GPs in Europe, Brazil, Israel, and New Zealand. We compared the percentage of cases that would be treated per countries. A logistic mixed-effects model was used to derive odds ratio (OR) for frailty with 95% confidence intervals (CI), adjusted for SBP, CVD, and GP characteristics (sex, location and prevalence of oldest-old per GP office, and years of experience). The mixed-effects model was used to account for the multiple assessments per GP.
Results: The 29 countries yielded 2543 participating GPs: 52% were female, 51% located in a city, 71% reported a high prevalence of oldest-old in their offices, 38% and had >20 years of experience. Across countries, considerable variation was found in the decision to start antihypertensive treatment in the oldest-old ranging from 34 to 88%. In 24/29 (83%) countries, frailty was associated with GPs’ decision not to start treatment even after adjustment for SBP, CVD, and GP characteristics (OR 0.53, 95%CI 0.48–0.59; ORs per country 0.11–1.78).
Conclusions: Across countries, we found considerable variation in starting antihypertensive medication in oldest-old. The frail oldest-old had an odds ratio of 0.53 of receiving antihypertensive treatment. Future hypertension trials should also include frail patients to acquire evidence on the efficacy of antihypertensive treatment in oldest-old patients with frailty, with the aim to get evidence-based data for clinical decision-making.
The tyrosine kinase inhibitor sunitinib is used as first‐line therapy in patients with metastasized renal cell carcinoma (mRCC), given in fixed‐dose regimens despite its high variability in pharmacokinetics (PKs). Interindividual variability of drug exposure may be responsible for differences in response. Therefore, dosing strategies based on pharmacokinetic/pharmacodynamic (PK/PD) models may be useful to optimize treatment. Plasma concentrations of sunitinib, its active metabolite SU12662, and the soluble vascular endothelial growth factor receptors sVEGFR‐2 and sVEGFR‐3, were measured in 26 patients with mRCC within the EuroTARGET project and 21 patients with metastasized colorectal cancer (mCRC) from the C‐II‐005 study. Based on these observations, PK/PD models with potential influence of genetic predictors were developed and linked to time‐to‐event (TTE) models. Baseline sVEGFR‐2 levels were associated with clinical outcome in patients with mRCC, whereas active drug PKs seemed to be more predictive in patients with mCRC. The models provide the basis of PK/PD‐guided strategies for the individualization of anti‐angiogenic therapies.
Faces are thought to be processed primarily according to their configurations which is in-ferred from comparisons with non-facial stimuli. While the whole (face) seems to be more than the sum of its parts, the same does not apply to objects which are processed analytically according to their featural information. A recent recognition model stresses the importance of certain visual information within facial stimuli. By applying a specific filtering technique, stimuli can be generated that are restricted to contain information of only a certain orienta-tion. Dakin and Watt (2009) reported greatest recognition performance with faces that only contained horizontally aligned information with accuracy continuously declining at vertical. Furthermore, they showed that, compared with images of natural scenes, horizontal contours within faces have an unusual tendency to fall into vertically co-aligned clusters which were labelled biological ‘bar code’ referring to a highly constrained one-dimensional code. Con-secutive research tested for face-specific processing by comparing faces and objects that displayed information of different orientations. Results suggested configural processing only for faces that contained horizontal information (Goffaux & Dakin, 2010). The findings con-tribute important insight on a still unanswered question in face processing research: what information is extracted from faces for recognizing them. Despite the importance of remembering human faces on a daily basis, this ability seems to develop disadvantageously over lifetime. Decreased accuracy cannot be attributed to de-creased general cognitive ability (Hildebrandt, Wilhelm, Schmiedek, Herzmann, & Sommer, 2011) and slower reactions times are assumed to be a product of decision making rather than sensory speed (Habak, Wilkinson, & Wilson, 2008). Considering the amount of published work on face recognition, there is a lack of studies available assessing this important ability at a higher age. New theoretical concepts are rarely examined with older participants, appar-ently assuming their general validity. The current dissertation tries to help fill this gap by assessing the importance of horizontal information from a developmental perspective com-paring younger and older adults under different experimental variations. The first study showed, that presenting older participants with horizontally filtered faces has a dispropor-tional negative impact on recognizing younger unfamiliar faces suggesting differential pro-cessing mechanisms, since recognizing stimuli that only contained vertical information did not differ between age groups. On this basis, the following study manipulated the presented stimulus material, since some evidence suggests that own-age faces are more easily recog-nized compared to faces of other ages, which is referred to as “own-age bias”. Therefore, the second study systematically assessed the impact of stimulus age on recognition sensitivity. Moreover, encoding modalities were varied by providing increased exposure duration to the stimuli. The results of the first study were replicated, as older participants’ performance was still poor at recognizing younger faces, independent from encoding modalities. However, similar face recognition sensitivity compared to younger adults was observable when filtered faces of the older adults’ own age had to be recognized. Interestingly, correlations between recognizing filtered and unfiltered faces were obtained for younger adults but not for older adults suggesting age variant processing of horizontal information. The last study assessed the importance of horizontal information with stimulus material familiar to the observer. Although research highlights differences between recognizing unfamiliar and familiar stimu-lus material, this factor is often not considered by contemporary research. By presenting par-ticipants with their own faces, a stimulus of greatest individual familiarity was chosen. The superiority of own face recognition over other familiar material is referred to as “self-face advantage” and has been shown in comparison with personally familiar faces (Keyes & Brady, 2010) and famous faces (Caharel et al., 2002). While younger adults indeed recog-nized their self-faces better compared to famous faces independent from stimuli being fil-tered or unfiltered, older participants displayed a completely different pattern including the inability to recognize their filtered self-faces. Again, significant associations were obtained between filtered and unfiltered recognition conditions suggesting convergent processing mechanisms for younger adults but not for the older age group. This dissertation provides a first insight in the divergence of response behavior in older adults with a recent face processing model. While the obtained data undermine the im-portance of horizontal information in younger adults by replicating and extending previously published work, a profoundly different type of processing is suggested at a higher age which largely relies on low-level pictorial information due to the inability to process horizontally filtered faces configurally. Specifically, it is suggested that with age, focusing on aging-salient features with configural processing disrupted may function as a critical source of di-agnostic information which can ultimately result in performance similar to younger adults.
Facial Width-to-Height Ratio (fWHR) has been linked with dominant and aggressive behavior in human males. We show here that on portrait photographs published online, chief executive officers (CEOs) of companies listed in the Dow Jones stock market index and the Deutscher Aktienindex have a higher-than-normal fWHR, which also correlates positively with their company’s donations to charitable causes and environmental awareness. Furthermore, we show that leaders of the world’s most influential non-governmental organizations and even the leaders of the Roman Catholic Church, the popes, have higher fWHR compared to controls on public portraits, suggesting that the relationship between displayed fWHR and leadership is not limited to profit-seeking organizations. The data speak against the simplistic view that wider-faced men achieve higher social status through antisocial tendencies and overt aggression, or the mere signaling of such dispositions. Instead they suggest that high fWHR is linked with high social rank in a more subtle fashion in both competitive as well as prosocially oriented settings.
Midkine is a pleiotropic factor, which is involved in angiogenesis. However, its mode of action in this process is still ill defined. The function of midkine in arteriogenesis, the growth of natural bypasses from pre-existing collateral arteries, compensating for the loss of an occluded artery has never been investigated. Arteriogenesis is an inflammatory process, which relies on the proliferation of endothelial cells and smooth muscle cells. We show that midkine deficiency strikingly interferes with the proliferation of endothelial cells in arteriogenesis, thereby interfering with the process of collateral artery growth. We identified midkine to be responsible for increased plasma levels of vascular endothelial growth factor A (VEGFA), necessary and sufficient to promote endothelial cell proliferation in growing collaterals. Mechanistically, we demonstrate that leukocyte domiciled midkine mediates increased plasma levels of VEGFA relevant for upregulation of endothelial nitric oxide synthase 1 and 3, necessary for proper endothelial cell proliferation, and that non-leukocyte domiciled midkine additionally improves vasodilation.
The data provided on the role of midkine in endothelial proliferation are likely to be relevant for both, the process of arteriogenesis and angiogenesis. Moreover, our data might help to estimate the therapeutic effect of clinically applied VEGFA in patients with vascular occlusive diseases.
This paper presents a follow-up study of Markovits et al.’s (2014) comparison of large samples of Greek employees before and at the onset of the economic crisis. Now at the crisis’ peak, we again sampled data from 450 employees about their job satisfaction, organizational commitment, regulatory focus, and burnout. Overall, compared to the two samples before, employees’ job attitudes further decrease with lower normative and higher continuance commitment, lower (extrinsic and intrinsic) job satisfaction and both lower promotion and (somewhat surprisingly) even lower prevention orientation. Expanding previous studies, results show that satisfaction and commitment are also related to burnout and that those participants who are currently employed but had experienced personal unemployment during the crisis showed more negative attitudes and higher burnout.
Compartmental models are the theoretical tool of choice for understanding single neuron computations. However, many models are incomplete, built ad hoc and require tuning for each novel condition rendering them of limited usability. Here, we present T2N, a powerful interface to control NEURON with Matlab and TREES toolbox, which supports generating models stable over a broad range of reconstructed and synthetic morphologies. We illustrate this for a novel, highly detailed active model of dentate granule cells (GCs) replicating a wide palette of experiments from various labs. By implementing known differences in ion channel composition and morphology, our model reproduces data from mouse or rat, mature or adult-born GCs as well as pharmacological interventions and epileptic conditions. This work sets a new benchmark for detailed compartmental modeling. T2N is suitable for creating robust models useful for large-scale networks that could lead to novel predictions. We discuss possible T2N application in degeneracy studies.
In the dentate gyrus (DG) of the mammalian hippocampus, neurogenesis continues to take place throughout an organism’s life. Adult neurogenesis includes proliferation and differentiation of neural stem cells into dentate granule cells (GCs) that mature and integrate into the existing cellular network. This thesis work presents a novel approach that enables longitudinal examination of living postnatally generated GCs in their endogenous niche by using retroviral (RV) labeling in organotypic entorhino-hippocampal slice cultures (OTCs). Older GCs were fluorescence-labeled with an adeno-associated virus controlled by the synapsin 1 promoter (AAV-Syn). The combination of time-lapse imaging and 3-D reconstruction of newborn developing GCs and older, more mature GCs enabled comparative analyses of dendritic growth and cellular dynamics as well as investigations of spine formation and the establishment of synaptic contacts.
Postnatal neurogenesis was studied in the mouse and rat DG in vivo by analysis of the distribution of chemical neuronal maturation markers doublecortin (DCX) and calbindin in combination with the GC marker Prox1 between P7 and P42. The marker expression patterns at different time points indicated that the number of mature GCs increased gradually over time and that young, immature GCs were added to the inner layers of the granule cell layer (GCL), as is the case in the adult brain. The most substantial shift in GC maturation took place between P7 and P14, though GCs in the rat DG matured faster (i.e. by ~5 days) than GCs in the mouse. Immunocytochemical in vitro analysis in OTCs at DIV 7, 14, and 28 exhibited a distribution of marker expression over time that was comparable to in vivo, though the number of DCX-expressing GCs was low at DIV 28, indicating a considerable decrease in neurogenesis rate over time in the OTC. Nevertheless, RV-labeling of newborn GCs at DIV 0 yielded successful visualization and enabled time-lapse imaging of complete developing GCs up to 4 weeks after mitosis. During the second week of development, newborn GCs exhibited a high level of structural dynamics, including extension and retraction of dendritic segments. In the third week, newborn GCs displayed high dendritic complexity which was followed by pronounced dendritic pruning. Finally, a phase of structural stabilization and local refinement could be observed during the fourth week. Older AAV-Syn-labeled GCs did not exhibit such dynamic structural remodeling. Anterograde tracing of entorhinal projection fibers using the biotinylated dextran amine Mini Ruby showed innervation of the outer molecular layer (OML) by entorhinal axons at early time points, i.e. DIV 8 when newborn GCs started to extend dendrites into the ML, as well as at DIV 20 when RV-labeled GCs exhibited elaborate dendritic trees with processes in the OML intermingling with entorhinal fibers. This shows that newborn GCs in the OTC grow into an area of existing entorhinal axon terminals, which is highly similar to the situation in the adult brain. Hence, the results show that postnatal neurogenesis can be studied effectively in the OTC system as a model of adult neurogenesis. The first appearance of spine-like protrusions in newborn GCs was observed two weeks post RV injection. Ultrastructural electron-microscopic images revealed that spines established synaptic contacts with axonal boutons. These findings suggest that newborn GCs are successfully integrated into the existing cellular circuitry in the OTC system. The high level of structural flexibility found in this study might be a necessary requisite of new neurons for successful dendritic maturation and functional integration into a neuronal network. Thus, live imaging of postnatally born GCs in the OTC appears as a useful novel approach to elucidate the mechanisms that affect cellular dynamics of neurogenesis.
The dentate gyrus (DG) is a unique structure of the hippocampus that is distinguished by ongoing neurogenesis throughout the lifetime of an organism. The development of the DG, which begins during late gestation and continues during the postnatal period, comprises the structural formation of the DG as well as the establishment of the adult neurogenic niche in the subgranular zone (SGZ). We investigated the time course of postnatal maturation of the DG in male C57BL/6J mice and male Sprague-Dawley rats based on the distribution patterns of the immature neuronal marker doublecortin (DCX) and a marker for mature neurons, calbindin (CB). Our findings demonstrate that the postnatal DG is marked by a substantial maturation with a high number of DCX-positive granule cells (GCs) during the first two postnatal weeks followed by a progression toward more mature patterns and increasing numbers of CB-positive GCs within the subsequent 2 weeks. The most substantial shift in maturation of the GC population took place between P7 and P14 in both mice and rats, when young, immature DCX-positive GCs became confined to the innermost part of the GC layer (GCL), indicative of the formation of the SGZ. These results suggest that the first month of postnatal development represents an important transition phase during which DG neurogenesis and the maturation course of the GC population becomes analogous to the process of adult neurogenesis. Therefore, the postnatal DG could serve as an attractive model for studying a growing and functionally maturing neural network. Direct comparisons between mice and rats revealed that the transition from immature DCX-positive to mature CB-positive GCs occurs more rapidly in the rat by approximately 4–6 days. The remarkable species difference in the speed of maturation on the GC population level may have important implications for developmental and neurogenesis research in different rodent species and strains.
Als die Existenz der Psychotherapeutischen Beratungsstelle für Studierende an der Goethe-Universität bedroht schien, da machte sich die Ehrensenatorin Renate von Metzler für diese wichtige Anlaufstelle für Studierende in schwierigen Lebenssituationen stark – mit Erfolg: Inzwischen nutzen jährlich mehr als 400 Ratsuchende dieses Angebot, damit hat sich ihre Zahl in kurzer Zeit verdoppelt. Ohne die „Anschubfinanzierung“ der Freunde und Förderer von 35.000 Euro wäre dies nicht so einfach möglich gewesen.
Indian Ocean came into existence with the breakup of Gondwana in the Mesozoic era. The presence of complex aseismic ridges and plateaus in the Indian Ocean makes it the least-understood of all the oceans. Mascarene Plateau, apart from Central Indian Ridge (CIR) running north-south between 2◦N and 25◦S in the Indian Ocean, is one such complex feature in the Indian Ocean that consists of Seychelles microcontinent in the north and the volcanic islands of Mauritius, La Réunion and Rodrigues in the south.
Most of the previous seismological studies on the islands of Mauritius, Rodrigues and Seychelles are restricted as each of them has only one operational permanent station. In the current study, I present the results obtained from the investigations of the seismological data obtained from the deployment of temporary seismic network on Mauritius (November, 2012–August, 2014) and Seychelles (March, 2013–March, 2015) under Réunion Hotspot and Upper Mantle–Réunions Unterer Mantel (RHUM–RUM) project and later in Rodrigues (September, 2014–June, 2016) under a collaborative project between Goethe-Universität, Frankfurt, Germany and Mauritius Oceanography Institute (MOI), Mauritius. Additional data from the permanent stations were also used in this study. The investigations and results are presented under three themes, namely: (1) crustal structure beneath Mauritius, (2) upper mantle anisotropy below Mauritius, Rodrigues and Seychelles and (3) intraplate seismicity in the Rodrigues–CIR region.
Upper mantle anisotropy in south-west Indian Ocean region are very limited, especially from the islands of Mauritius and Rodrigues. With the new data from the seismic stations deployed in Mauritius and Seychelles, under RHUM–RUM, and permanent stations in Rodrigues, I constrain the upper mantle flow pattern beneath these islands. From the joint-splitting analysis, I obtain fast-polarisation direction (φ) dominant in N80◦E and delay time (δt) of ≈0.85 s for Mauritius and φ tending east–west in Rodrigues with δt of ≈1.1 s. Parabolic asthenospheric flow model explains the orientation of the fast-polarisation direction beneath Mauritius, whereas deep mantle circulation patterns best explain the horizontal alignment of the fast-polarisation direction in Rodrigues. From Seychelles data, the results show φ trending NE and δt ≈0.74 s, even for the island close to Amirante Ridge, suggesting an asthenospheric deformation induced by relative motion between the plate and the deep mantle flow.
It has recently been suggested that the volcanic island of Mauritius may be underlain by a remnant of continental origin termed “Mauritia.” To constrain the crustal thickness beneathMauritius, I analysed data from 11 land stations, 10 of which were deployed recently under the RHUM–RUM project. From the recordings, I obtained 382 P-receiver functions. On the obtained receiver functions, I applied the H–κ stacking technique and derived the crustal thickness of ≈10–15 km. I observe a considerable variation in the VP/VS ratio caused by a lack of clear multiples. Using forward modelling of receiver functions, I show that the lack of clear multiples can be explained by a transitional Moho, where the velocity increases gradually. The modelling further indicates that the thickness of this gradient zone is estimated to be ≈10 km. I argue that my findings suggest oceanic crust thickened by crustal underplating due to the mantle plume currently located beneath La Réunion.
Seismicity around Rodrigues Island is generally associated with events recorded by the global networks along the CIR. Using seismological array techniques on the data collected by the temporary deployment of seismic array on Rodrigues Island for a period of 22 months (September, 2014–June 2016), 62 new events were located, which were not reported by any global network. Determination of backazimuth and apparent velocity were performed by applying array methods in the time-domain instead of the more conventional frequency-domain analysis. Event distances were calculated using a 1-D velocity model and the measured travel-time differences between S- and P-wave arrivals. Local magnitudes of the events were obtained by removing the velocity response from the seismographs and then convolving with Wood–Anderson transfer function to obtain ground motion in nanometers. Most of the newly-detected events are located off the ridge axis and can be classified as intraplate events. Three different seismic clusters were observed around the island. Most of the events were localised in the north-east of Rodrigues at a distance of ≈138 km from the reference station. A distinguishable swarm of earthquakes was observed on the west of the spreading segment from March to April 2015. The local magnitudes (ML) of the events varied between 1.6 and 3.7.
Mutualistic interactions between plants and animals can affect both plant and animal communities, and potentially leave imprints on plant demography. Yet, no study has simultaneously tested how trait variation in plant resources shapes the diversity of animal consumers, and how these interactions influence seedling recruitment. Here, we analyzed whether (i) phylogenetic diversity and functional diversity of fruiting plants were correlated with the corresponding diversity of frugivorous birds, and (ii) whether phylogenetic diversity and functional identity of plant and bird communities influenced the corresponding diversity and identity of seedling communities. We recorded mutualistic interactions between fleshy-fruited plants and frugivorous birds and seedling communities in 10 plots along an elevational gradient in the Colombian Andes. We built a phylogeny for plants/seedlings and birds and measured relevant morphological plant and bird traits that influence plant-bird interactions and seedling recruitment. We found that phylogenetic diversity and functional diversity of frugivorous birds were positively associated with the corresponding diversities of fruiting plants, consistent with a bottom-up effect of plants on birds. Moreover, the phylogenetic diversity of seedlings was related to the phylogenetic diversity of plants, but was unrelated to the phylogenetic diversity of frugivorous birds, suggesting that top-down effects of animals on seedlings were weak. Mean seed mass of seedling communities was positively associated with the mean fruit mass of plants, but was not associated with the mean avian body mass in the frugivore communities. Our study shows that variation in the traits of fleshy-fruited plants was associated with the diversity of frugivorous birds and affected the future trajectory of seedling recruitment, whereas the morphological traits of animal seed dispersers were unrelated to the phylogenetic and functional structure of seedling communities. These findings suggest that bottom-up effects are more important than top-down effects for seed-dispersal interactions and seedling recruitment in diverse tropical communities.
Objectives: There is promising evidence that mindfulness-based interventions are effective in reducing the symptoms of posttraumatic stress disorder (PTSD). However, until now, studies have often lacked a full clinical PTSD assessment, and interventions are often administered in addition to other interventions. This study examined the feasibility of mindfulness-based stress reduction (MBSR) as a standalone intervention in patients with PTSD who have experienced mixed traumatic events.
Method: Fourteen patients participated in 8 weeks of MBSR. The patients were assessed prior to treatment, post-treatment and at a 1-month follow-up through self-ratings (e.g., the Davidson Trauma Scale) and the Clinician-Administered PTSD Scale to determine the effects of the intervention. Furthermore, after the intervention, the patients participated in qualitative interviews regarding their experiences with MBSR and their ideas for future improvements.
Results: Nine patients finished the program, and these patients considered the exercises to be applicable and helpful. In the Clinician-Administered PTSD Scale, we found large effects regarding the reduction of PTSD symptoms among completers (Cohen's d = 1.2). In the Davidson Trauma Scale, the effect sizes were somewhat lower (Cohen's d = 0.6) but nevertheless confirmed the efficacy of MBSR in reducing PTSD symptoms. In the qualitative interviews, the patients reported an augmentation of wellbeing and improvement regarding the handling of difficult situations and more distance from the traumatic event.
Conclusion: Despite the large effects, the high dropout rates and the results of the post-treatment interviews suggest that the intervention should be better adapted to the needs of PTSD patients, e.g., by giving more information regarding the exercises and by including shorter exercises to manage acute distress.
Impact of human mesenchymal stromal cells on antifungal host response against Aspergillus fumigatus
(2017)
Mesenchymal stromal cells (MSCs) are increasingly given as immunotherapy to hematopoietic stem cell transplant (HSCT) recipients with refractory graft-versus-host disease (GvHD). Whereas the immunosuppressive properties of MSCs seem to be beneficial in GvHD, there is, at the same time, major concern that MSCs increase the risk for infection. We therefore investigated the interplay of human MSCs with Aspergillus fumigatus and the impact of MSCs on different arms of the anti-Aspergillus host response in vitro. Although A. fumigatus hyphae increase mRNA levels of IL6 in MSCs, the extracellular availability of IL-6 and other pro-inflammatory cytokines remains unaffected. Human MSCs are able to phagocyte Aspergillus conidia, but phagocytosis of conidia is not associated with an alteration of the cytokine production by MSCs. In addition, human MSCs do not affect activation and function of A. fumigatus specific CD4+ T cells, and MSCs do not negatively impact the oxidative burst activity of phagocytes. Our in vitro data indicate that administration of human MSCs is not associated with a negative impact on the host response against A. fumigatus and that the fungus does not stimulate MSCs to increase the release of those cytokines which play a central role in the pathophysiology of GvHD.
Objective: Most patients suffering with rheumatic diseases who undergo surgical treatment are receiving immune-modulating therapy. To determine whether these medications affect their outcomes a national registry was established in Germany by the German Society of Surgery (DGORh). Data from the first 1000 patients were used in a pilot study to identify relevant corisk factors and to determine whether such a registry is suitable for developing accurate and relevant recommendations.
Design and participants: Data were collected from patients undergoing surgical treatments with their written consent. A second consent form was used, if complications occurred. During this pilot study, in order to obtain a quicker overview, risk factors were considered only in patients with complications. Only descriptive statistical analysis was employed in this pilot study due to limited number of observed complications and inhomogeneous data regarding the surgery and the medications the patients received. Analytical statistics will be performed to confirm the results in a future outcome study.
Results: Complications occurred in 26 patients and were distributed equally among the different types of surgeries. Twenty one of these patients were receiving immune-modulating therapy at the time, while five were not. Infections were observed in 2.3% of patients receiving and in 5.1% not receiving immunosuppression.
Conclusions: Due to the low number of cases, inhomogeneity in the diseases and the treatments received by the patients in this pilot study, it is not possible to develop standardised best-practice recommendations to optimise their care. Based on this observation we conclude that in order to be suitable to develop accurate and relevant recommendations a national registry must include the most important and relevant variables that impact the care and outcomes of these patients.
Background: Posttraumatic Stress Disorder (PTSD) related to childhood sexual abuse (CSA) is often associated with a wide range of trauma-related aversive emotions such as fear, disgust, sadness, shame, guilt, and anger. Intense experience of aversive emotions in particular has been linked to higher psychopathology in trauma survivors. Most established psychosocial treatments aim to reduce avoidance of trauma-related memories and associated emotions. Interventions based on Dialectical Behavior Therapy (DBT) also foster radical acceptance of the traumatic event.
Methods: This study compares individual ratings of trauma-related emotions and radical acceptance between the start and the end of DBT for PTSD (DBT-PTSD) related to CSA. We expected a decrease in trauma-related emotions and an increase in acceptance. In addition, we tested whether therapy response according to the Clinician Administered PTSD-Scale (CAPS) for the DSM-IV was associated with changes in trauma-related emotions and acceptance. The data was collected within a randomized controlled trial testing the efficacy of DBT-PTSD, and a subsample of 23 women was included in this secondary data analysis.
Results: In a multilevel model, shame, guilt, disgust, distress, and fear decreased significantly from the start to the end of the therapy whereas radical acceptance increased. Therapy response measured with the CAPS was associated with change in trauma-related emotions.
Conclusions: Trauma-related emotions and radical acceptance showed significant changes from the start to the end of DBT-PTSD. Future studies with larger sample sizes and control group designs are needed to test whether these changes are due to the treatment.
Trial registration: ClinicalTrials.gov, number NCT00481000
Molluscs are the second most species-rich phylum in the animal kingdom, yet only eleven genomes of this group have been published so far. Here, we present the draft genome sequence of the pulmonate freshwater snail Radix auricularia. Six whole genome shotgun libraries with different layouts were sequenced. The resulting assembly comprises 4,823 scaffolds with a cumulative length of 910 Mb and an overall read coverage of 72x. The assembly contains 94.6 % of a metazoan core gene collection, indicating an almost complete coverage of the coding fraction. The discrepancy of ~690 Mb compared to the estimated genome size of R. auricularia (1.6 Gb) results from a high repeat content of 70 % mainly comprising DNA transposons. The annotation of 17,338 protein coding genes was supported by the use of publicly-available transcriptome data. This draft will serve as starting point for further genomic and population genetic research in this scientifically important phylum.
Crescentic rapidly progressive glomerulonephritis (RPGN) represents the most aggressive form of acquired glomerular disease. While most therapeutic approaches involve potentially toxic immunosuppressive strategies, the pathophysiology remains incompletely understood. Podocytes are glomerular epithelial cells that are normally growth-arrested because of the expression of cyclin-dependent kinase (CDK) inhibitors. An exception is in RPGN where podocytes undergo a deregulation of their differentiated phenotype and proliferate. Here we demonstrate that microRNA-92a (miR-92a) is enriched in podocytes of patients and mice with RPGN. The CDK inhibitor p57Kip2 is a major target of miR-92a that constitutively safeguards podocyte cell cycle quiescence. Podocyte-specific deletion of miR-92a in mice de-repressed the expression of p57Kip2 and prevented glomerular injury in RPGN. Administration of an anti-miR-92a after disease initiation prevented albuminuria and kidney failure, indicating miR-92a inhibition as a potential therapeutic strategy for RPGN. We demonstrate that miRNA induction in epithelial cells can break glomerular tolerance to immune injury.
Can variances of latent variables be scaled in such a way that they correspond to eigenvalues?
(2017)
The paper reports an investigation of whether sums of squared factor loadings obtained in confirmatory factor analysis correspond to eigenvalues of exploratory factor analysis. The sum of squared factor loadings reflects the variance of the corresponding latent variable if the variance parameter of the confirmatory factor model is set equal to one. Hence, the computation of the sum implies a specific type of scaling of the variance. While the investigation of the theoretical foundations suggested the expected correspondence between sums of squared factor loadings and eigenvalues, the necessity of procedural specifications in the application, as for example the estimation method, revealed external influences on the outcome. A simulation study was conducted that demonstrated the possibility of exact correspondence if the same estimation method was applied. However, in the majority of realized specifications the estimates showed similar sizes but no correspondence.
Background: Infections with the hepatitis C virus (HCV) are a global public health problem. Long-term consequences are the development of liver cirrhosis and hepatocellular carcinoma. Newly introduced direct acting antivirals, especially interferon-free regimens, have improved rates of sustained viral response above 90% in most patient groups and allow treating patients who were ineligible for treatment in the past. These new regimens have replaced former treatment and are recommended by current guidelines. However, there is an ongoing discussion on high pharmaceutical prices. Our aim was to assess the long-term cost-effectiveness of treating hepatitis C genotype 1 patients with sofosbuvir/ledipasvir (SOF/LDV) treatment in Germany.
Material and Methods: We used a Markov cohort model to simulate disease progression and assess cost-effectiveness. The model calculates lifetime costs and outcomes (quality-adjusted life years, QALYs) of SOF/LDV and other strategies. Patients were stratified by treatment status (treatment-naive and treatment-experienced) and absence/presence of cirrhosis. Different treatment strategies were compared to prior standard of care. Sensitivity analyses were performed to evaluate model robustness.
Results: Base-case analyses results show that in treatment-naive non-cirrhotic patients treatment with SOF/LDV dominates the prior standard of care (is more effective and less costly). In cirrhotic patients an incremental cost-effectiveness ratio (ICER) of 3,383 €/QALY was estimated. In treatment-experienced patients ICERs were 26,426 €/QALY and 1,397 €/QALY for treatment-naive and treatment-experienced patients, respectively. Robustness of results was confirmed in sensitivity analyses.
Conclusions: Our analysis shows that treatment with SOF/LDV is cost-effective compared to prior standard of care in all patient groups considering international costs per QALY thresholds.
Background: Certain disadvantages of the standard hematopoietic stem and progenitor cell (HSPC) mobilizing agent G-CSF fuel the quest for alternatives. We herein report results of a Phase I dose escalation trial comparing mobilization with a peptidic CXCR4 antagonist POL6326 (balixafortide) vs. G-CSF.
Methods: Healthy male volunteer donors with a documented average mobilization response to G-CSF received, following ≥6 weeks wash-out, a 1–2 h infusion of 500–2500 µg/kg of balixafortide. Safety, tolerability, pharmacokinetics and pharmacodynamics were assessed.
Results: Balixafortide was well tolerated and rated favorably over G-CSF by subjects. At all doses tested balixafortide mobilized HSPC. In the dose range between 1500 and 2500 µg/kg mobilization was similar, reaching 38.2 ± 2.8 CD34 + cells/µL (mean ± SEM). Balixafortide caused mixed leukocytosis in the mid-20 K/µL range. B-lymphocytosis was more pronounced, whereas neutrophilia and monocytosis were markedly less accentuated with balixafortide compared to G-CSF. At the 24 h time point, leukocytes had largely normalized.
Conclusions: Balixafortide is safe, well tolerated, and induces efficient mobilization of HSPCs in healthy male volunteers. Based on experience with current apheresis technology, the observed mobilization at doses ≥1500 µg/kg of balixafortide is predicted to yield in a single apheresis a standard dose of 4× 10E6 CD34+ cells/kg from most individuals donating for an approximately weight-matched recipient. Exploration of alternative dosing regimens may provide even higher mobilization responses.
Trial Registration European Medicines Agency (EudraCT-Nr. 2011-003316-23) and clinicaltrials.gov (NCT01841476)
The 23Al(p, γ)24Si stellar reaction rate has a significant impact on the light-curve emitted in X-ray bursts. Theoretical calculations show that the reaction rate is mainly determined by the properties of direct capture as well as low-lying 2+ states and a possible 4+ state in 24Si. Currently, there is little experimental information on the properties of these states.
In this proceeding we will present a new experimental study to investigate this reaction, using the surrogate reaction 23Al(d,n) at 47 AMeV at the National Superconducting Cyclotron Laboratory (NSCL). We will discuss our new experimental setup which allows us to use full kinematics employing the Gamma-Ray Energy Tracking In-beam Nuclear Array (GRETINA) to detect the γ-rays following the de-excitation of excited states of the reaction products and the Low Energy Neutron Detector Array (LENDA) to detect the recoiling neutrons. The S800 was used for identification of the 24Si recoils. As a proof of principle to show the feasibility of this concept the Q-value spectrum of 22Mg(d,n)23Al is reconstructed.
Savannas provide essential ecosystem services for human well-being in West Africa. Thus, ecosystem change not only directly affects biodiversity but also human livelihoods. Human land use considerably shaped these savanna ecosystems for millennia, particularly agriculture, livestock grazing, logging and the collection of non-timber forest products (NTFPs). NTFPs are wild plant products and comprise all organic matter from herbaceous plants, shrubs, and trees (excluding timber). Current increasing land use pressure through fast demographic changes is widely esteemed as a severe threat for savanna biodiversity and the socio-economy of rural communities. In consideration of the pivotal role of NTFP species for biodiversity and livelihoods, it is important to evaluate the effect of increasing land use change on savanna vegetation and on its provisioning service for human well-being. Thus, the major aim of this thesis is to investigate the impacts of land use intensification on vegetation composition, diversity and function and its consequences for provisioning ecosystem services (NTFPs) and human well-being in a West African savanna.
The research for this study was conducted in the North Sudanian vegetation zone of south-eastern Burkina Faso, where population growth exceeds the nationwide trend. Generally, Burkina Faso belongs to the worldwide poorest countries, where nearly one quarter of the population suffers from malnutrition (FAO 2014). The integration of NTFPs and particularly wild food species into rural household economies is, thus, an important measure in the national combat against poverty and food insecurity (FAO 2014). Against this background, I focus on vegetation changes, the economic importance of NTFPs as well as the decrease and substitution of wild food species in this study.
Vegetation resurveys of different vegetation types since the early 1990s showed that land use change led to more pronounced changes in the herbaceous than in the woody vegetation layer. Most woody vegetation types stayed stable in species composition and richness, even though some highly useful tree species (Vitellaria paradoxa, Parkia biglobosa) declined in some woody vegetation types. In contrast, in most herbaceous vegetation types species richness increased and species composition considerably changed. This change might be explained by a general ruderalisation process through a pronounced increase of wide-ranging herbaceous species. However, in spite of a general species increase in the herbaceous layer, a decrease of preferred herbaceous fodder species was found. Thus, the decline of useful species in both layers is alarming. Herbaceous vegetation types also showed more pronounced changes in plant functional trait characteristics in comparison to woody vegetation types. However, an increase of smaller plant species and species with a high diaspore terminal velocity (VTerm) was found in both vegetation layers. Since these two trait responses are generally related to grazing and browsing, the strong increase of livestock herds is likely to be responsible for the detected vegetation changes.
In addition to the vegetation study, interviews showed that all useful food species were widely considered to decline. The two economically most important tree species, the shea tree (Vitellaria paradoxa) and the locust bean tree (Parkia biglobosa) that contribute with 70% to wild food income, were considered among the most declining species of all cited wild food species. On this matter, local perceptions of species decline and results from field observations are in accordance. However, a wide range of cited substitutes indicated a great knowledge on alternative plant species in the area. Most wild food species are, however, substituted by other highly valued wild food species. Although our results suggest that rural communities are able to cope with the decrease or absence of wild food species, growing decline of one species would concurrently increase the pressure on other native food species. Therefore, the need to counteract the decrease of highly useful wild food species should be of high priority in management measures. In general, I showed that NTFPs are an essential component in rural households, since it contributed with 45 % to total household income. Significant differences in NTFP dependency between the two investigated villages and across the three main ethnic groups were detected, reflecting different traditional uses and harvesting practices. In general, it was shown that poorer households depend more on NTFP income than wealthier households. Against the background of this study, management strategies for agroforestry systems and poverty alleviation should consider local differences, and ethnicity-dependent NTFP-use patterns.
Overall, the combination of field studies on temporal and functional vegetation change with socio-economic and ethno-botanic interviews increases the knowledge on qualitative and quantitative vegetation changes and on the consequences for rural populations. This thesis gives a thorough insight into decreasing trends of economically valued plant species and thus gives evidence on the consequences of vegetation changes for ecosystem services of West African savanna ecosystems. Further, different NTFP-dependencies and use preferences according to socio-economic and cultural variables, such as ethnicity, present a valuable basis for specific decision-making and should be considered in management plans.
In the title compound, C17H18N2O, the central carbon atom with the OH substituent and one of the (E)-benzylideneamino substituents are disordered over two sets of sites with occupancies of 0.851 (4) and 0.149 (4). The relative positions of the two disorder components is equivalent to a rotation of approximately 60° about the C—N single bond. In the crystal, the molecules are held together by O—H...N hydrogen bonds, forming simple C(5) chains along the b-axis direction. In addition, pairs of the chains are further aggregated by weak C—H...π interactions.
The asymmetric unit of the title compound, C21H28N4O, consists of two unique molecules linked by an O—H⋯N hydrogen bond. The conformation of both C=N bonds is E and the azomethine functional groups lie close to the plane of their associated benzene rings in each of the independent molecules. The dihedral angles between the two benzene rings are 83.14 (4) and 75.45 (4)°. The plane of the one of the N(CH3)2 units is twisted away from the benzene ring by 18.8 (2)°, indicating loss of conjugation between the lone electron pair and the benzene ring. In the crystal structure, O—H⋯N hydrogen bonds together with C—H⋯O hydrogen bonds link neighbouring supramolecular dimers into a three-dimensional network.
The asymmetric unit of the title co-crystalline adduct, 1,3,6,8-tetraazatricyclo[4.4.1.13,8]dodecane (TATD)–4-iodophenol (1/2), C8H16N4·2C6H5IO, comprises a half molecule of the aminal cage polyamine plus a 4-iodophenol molecule. A twofold rotation axis generates the other half of the adduct. The components are linked by two intermolecular O—H⋯N hydrogen bonds. The adducts are further linked into a three-dimensional framework structure by a combination of N⋯I halogen bonds and weak non-conventional C—H⋯O and C—H⋯I hydrogen bonds.
In the title compound, C26H24N2O2, the oxazine moiety is fused to a naphthalene ring system. The asymmetric unit consists of one half of the molecule, which lies about an inversion centre. The C atoms of the ethylene spacer group adopt an antiperiplanar arrangement. The oxazine ring adopts a half-chair conformation. In the crystal, supramolecular chains running along the b axis are formed via short C—H⋯π contacts. The crystal studied was a non-merohedral twin with a fractional contribution of 0.168 (2) of the minor twin component.
The asymmetric unit of the title compound, C18H18I2N2O2, consists of one half-molecule, completed by the application of inversion symmetry. The molecule adopts the typical structure for this class of bis-benxozazines, characterized by an anti orientation of the two benzoxazine rings around the central C—C bond. The oxazinic ring adopts a half-chair conformation. In the crystal, molecules are linked by C—I⋯N short contacts [I⋯N = 3.378 (2) Å], generating layers lying parallel to the bc plane.
Dendrites form predominantly binary trees that are exquisitely embedded in the networks of the brain. While neuronal computation is known to depend on the morphology of dendrites, their underlying topological blueprint remains unknown. Here, we used a centripetal branch ordering scheme originally developed to describe river networks—the Horton-Strahler order (SO)–to examine hierarchical relationships of branching statistics in reconstructed and model dendritic trees. We report on a number of universal topological relationships with SO that are true for all binary trees and distinguish those from SO-sorted metric measures that appear to be cell type-specific. The latter are therefore potential new candidates for categorising dendritic tree structures. Interestingly, we find a faithful correlation of branch diameters with centripetal branch orders, indicating a possible functional importance of SO for dendritic morphology and growth. Also, simulated local voltage responses to synaptic inputs are strongly correlated with SO. In summary, our study identifies important SO-dependent measures in dendritic morphology that are relevant for neural function while at the same time it describes other relationships that are universal for all dendrites.
We derive three exact sum rules for the spectral function of the electromagnetic current with zero spatial momentum at finite temperature. Possible applications of the three sum rules to lattice computations of the spectral function and transport coefficients are also discussed: We propose an ansatz for the spectral function that can be applied to all three sum rules and fit it to available lattice data of the Euclidean vector correlator above the critical temperature. As a result, we obtain estimates for both the electrical conductivity σ and the second order transport coefficient τJ.
Der Frage, weshalb das Lesen von Literatur so essentiell für das Menschsein ist, widmet sich Maria Nikolajeva mit ihrer theoretischen Studie, die in der Reihe "Children’s Literature, Culture, and Cognition" erschienen ist. Sie integriert kognitionswissenschaftlich basierte Ansätze in die Kinder- und Jugendliteraturforschung für die Diskussion ihrer zentralen Annahme, dass wir durch das Lesen fiktionaler Texte über die Welt lernen, Mitmenschen besser verstehen, unsere Selbsterkenntnis erhöhen und uns ethisches Wissen aneignen. ...
2017 war in Deutschland eine Ausstellung zu erleben, deren Idee darauf beruhte, durch die Gestaltung einer "Magic City" der Kunst der Straße (Street Art) in einem künstlich geschaffenen Raum Ausdruck zu verleihen (www.magiccity.de). Street Art Künstler aus fünf Kontinenten schufen dabei eine urbane Welt, indem sie aus multimedialen Installationen oder Wandgemälden mit 3-D-Effekt wahrhaft magische Räume konstruierten, die vor allem jugendliche Besucher zu begeistern wussten. Fiktionale Räume trafen auf Realität, und es kam zu lebendigen und interaktiven Diskursen, die neben dem ästhetischen Reiz der Präsentationen auch vielfältige Fragen nach dem Wechselverhältnis zwischen Mensch und Raum in der modernen Welt debattierten. ...
Der mit zahlreichen farbigen Abbildungen versehene Band wurde anlässlich von Kurt Franz’ 75. Geburtstag herausgegeben und versammelt einen "Querschnitt" (VIII) seiner Arbeiten zur Kinderlyrik, einem Thema, mit dem sich Franz "ein Leben lang beschäftigt" (V) hat. Mit der Monographie Kinderlyrik. Struktur, Rezeption, Didaktik, die der Literaturdidaktiker 1979 publizierte, hat der vorliegende Band, in dem kürzere Beiträge aus den letzten beiden Jahrzehnten versammelt sind, demnach nur den Obertitel gemeinsam. Während es Franz seinerzeit darum ging, die Kinderlyrik als "wichtigen Bereich der 'Kinderkultur' in seiner Gesamtheit zu erfassen" (Franz 1979, 7), präsentiert der aktuelle Band Aspekte der Kinderlyrik in Einzelstudien, thematisch in die Kapitel "Begriffe und Geschichte", "Tradition und Innovation", "Themen und Motive", "Formen und Strukturen" und "Rezeption und Vermittlung" gegliedert. Ein bibliographischer Anhang und ein "Nachweis der Beiträge" beschließen den Band. ...
Nachdem es schon seit den 1980er Jahren Untersuchungen zu einem gendersensiblen Unterricht mit Kinder- und Jugendliteratur gegeben hatte, interessierte man sich in Folge des PISA-Schocks nach dem Jahr 2000 plötzlich in besonderer Weise für geschlechterspezifische Unterschiede im Leseverhalten. Diese wurden dramatisiert, weil man merkte, dass der männlichen Jugend sogar die einfachsten Kompetenzen der Informationsentnahme aus Texten fehlte. "Genderkompetenz" bestand in diesem Zusammenhang zunächst daraus, dass DeutschlehrerInnen versuchten, Jungen zum Lesen zu bringen. Auf der Strecke blieb eine genaue Lektüre der Texte, die man den SchülerInnen vorlegte, zugunsten einer allein am Schülersubjekt orientierten empirischen Leserforschung. ...
The mTOR (mechanistic target of rapamycin) inhibitor rapamycin has long been known for its immune suppressive properties, but it has shown limited therapeutic success when given systemically to patients with psoriasis. Recent data have shown that the mTOR pathway is hyperactivated in lesional psoriatic skin, which probably contributes to the disease by interfering with maturation of keratinocytes. This study investigated the effect of topical rapamycin treatment in an imiquimod-induced psoriatic mouse model. The disease was less severe if the mice had received rapamycin treatment. Immunohistological analysis revealed that rapamycin not only prevented the activation of mTOR signalling (P-mTOR and P-S6 levels), but almost normalized the expression of epidermal differentiation markers. In addition, the influx of innate immune cells into the draining lymph nodes was partially reduced by rapamycin treatment. These data emphasize the role of mTOR signalling in the pathogenesis of psoriasis, and support the investigation of topical mTOR inhibition as a novel anti-psoriatic strategy.
Martina Seifert widmet sich in ihrer komparatistisch-imagologisch ausgerichteten Studie, ihrer Dissertation, dem Kanadabild in der in Deutschland erschienenen Kinder- und Jugendliteratur. Sie behandelt den Zeitraum von 1899 bis 2005. Die vielschichtig und komplex angelegte Studie untersucht anhand von ca. 1000 kinder- und jugendliterarischen Texten sowohl "die heteroimagotypen Konzeptionen in den Produktionen deutschsprachiger Autoren [...], i. e. die Heteroimages von Kanada bzw. deren Funktionen in Abhängigkeit von den historisch variablen Autoimages" (Teil I der Arbeit) als auch die Frage, "inwieweit die im Subsystem zirkulierenden Heteroimages die Übersetzungsgeschichte der kanadischen Kinder- und Jugendliteratur ins Deutsche beeinflussten, [also] inwieweit diese im zielkulturellen System Aufnahme fanden oder nicht" (Teil II, 14f.). Jedem der beiden Teile liegen komplexe Fragestellungen zugrunde, der die Autorin im Laufe ihrer Analyse mehr als gerecht wird...
Alzheimer’s disease is a chronic neurodegenerative disease that causes problems with memory, thinking and behavior. The pathophysiological hallmarks of AD are extracellular senile plaques and intracellular neurofibrillary tangles. Amyloid plaques mainly contain the amyloid-β (Aβ) peptide, which appears as a cleavage product of the APP. APP is a type I transmembrane protein with a large extracellular domain and a short cytoplasmic tail. It is expressed in variety of tissues e.g. in neuronal tissue (brain, spinal cord, retina), and non-neuronal tissues (kidney, lung, pancreas, prostate gland, and thyroid gland) (Dawkins and Small, 2014). APP has been studied because of its link to AD, however, its role in normal brain function is poorly understood. APP is processed by two different pathways, amyloidogenic pathway and non-amyloidogenic pathway. In physiological condition, the majority of APP is processed via the non-amyloidogenic, thus leading to the generation of the secreted N-terminal APP processing product sAPPα. sAPPα is formed due to the cleavage of APP by α-secretase. In previous studies, our group has shown that sAPPα produce potent neuroprotective effect by altering gene expression, as well as by antagonizing several different types of neurotoxic stress stimuli (Copanaki et al., 2010; Kögel et al., 2003, 2005; Milosch et al., 2014). Several studies have shown that protein degradation is reduced in AD (Hong et al., 2014; Lipinski et al., 2010) but the role of APP and its cleavage products in protein degradation is still unknown. This thesis discusses about the physiological functions of APP in neuroprotection and protein homeostasis.
In the first part of the thesis (Section 4.1 - 4.4), the neuroprotective properties of yeast derived sAPPα and E1 (N-terminal domain of sAPPα) were investigated under serum and glucose deprivation conditions. In previous work, it was shown that recombinant sAPPα evoked a significant decrease in serum deprivation triggered cell death in human SH-SY5Y neuroblastoma cells and mouse embryonic fibroblast MEF cells. It was also observed that sAPPα induces the phosphorylation of Akt which leads to neuroprotection (Milosch et al., 2014). This study investigated whether this neuroprotection is associated with altered expression of downstream intracellular Akt targets such as FoxO, Bim, Bcl-xL and Mcl-1 under stress conditions. Here it was shown that sAPPα prevents activation and nuclear translocation of FoxO. FoxO act as a transcription factor for different proapoptotic genes such as Bim. It was also observed that Bim protein and mRNA expression was significantly reduced with sAPPα and E1 treatment. The expression of antiapoptotic protiens such as Bcl-xL and Mcl-1 were also examined and it was observed that sAPPα and E1 increases expression of both these proteins. Furthermore, it was previously demonstrated that uncleaved holo-APP functionally cooperates with sAPPα to activate Akt and provide neuroprotection (Milosch et al., 2014). Therefore, to investigate the function of the APP in sAPPα regulated Akt downstream proteins expressions, MEF APP KO cells were used. E1 and sAPPα only showed neuroprotective modulatory effect on these Akt downstream targets in MEF wt cells, but not in APP KO cells. In addition, sAPPα also showed neuroprotection in primary wt hippocampal neurons under trophic factor deprivation. Cellular fractionation experiments were also done to determine the role of sAPPα in cytochrome c release from mitochondria. It was observed that sAPPα treatment can inhibit mitochondrial cytochrome c release in wt MEF cells.
The second part of the thesis (Section 4.5 - 4.9) discusses about the role of sAPPα in protein homeostasis. It was observed that sAPPα prevents proteotoxic stress induced BAG3 protein expression in SH-SY5Y and MEF cells. This was also observed in mRNA levels which indicate a transcriptional regulation. Furthermore, treatment with sAPPα was also shown to decrease aggresomes formation. Aggresomes are perinuclear aggregates which are formed due to accumulation of damaged and misfolded proteins and BAG3 plays important role in their formation and the transport of degradation prone proteins into these structures. The analysis of proteasomal activity showed a reduced accumulation of proteasomal substrate d2 by sAPPα under proteasomal stress. In proteasomal activity assay, sAPPα was shown to increase the degradation of proteasomal substrate SUC-LLVY-AMC and the fluorigenic signal was measured spectrophotometrically. The sAPPβ fragment which is generated via the amyloidogenic pathway was also examined for its role in BAG3 expression and proteasomal degradation. sAPPβ, which has almost similar structure as sAPPα, only 17 amino acids at the C-terminus is missing, was failed to modulate BAG3 expression and proteostasis. This indicates that these biological effects are highly specific for sAPPα.
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