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We present the results of two-pion production in tagged quasi-free np collisions at a deutron incident beam energy of 1.25 GeV/c measured with the High-Acceptance Di-Electron Spectrometer (HADES) installed at GSI. The specific acceptance of HADES allowed for the first time to obtain high-precision data on π+π− and π−π0 production in np collisions in a region corresponding to large transverse momenta of the secondary particles. The obtained differential cross section data provide strong constraints on the production mechanisms and on the various baryon resonance contributions (∆∆, N(1440), N(1520), ∆(1600)). The invariant mass and angular distributions from the np → npπ+π −and np → ppπ−π0 reactions are compared with different theoretical model predictions.
Sleep is regulated in a time-of-day dependent manner and profits working memory. However, the impact of the circadian timing system as well as contributions of specific sleep properties to this beneficial effect remains largely unexplored. Moreover, it is unclear to which extent inter-individual differences in sleep-wake regulation depend on circadian phase and modulate the association between sleep and working memory. Here, sleep electroencephalography (EEG) was recorded during a 40-h multiple nap protocol, and working memory performance was assessed by the n-back task 10 times before and after each scheduled nap sleep episode. Twenty-four participants were genotyped regarding a functional polymorphism in adenosine deaminase (rs73598374, 12 G/A-, 12 G/G-allele carriers), previously associated with differences in sleep-wake regulation. Our results indicate that genotype-driven differences in sleep depend on circadian phase: heterozygous participants were awake longer and slept less at the end of the biological day, while they exhibited longer non rapid eye movement (NREM) sleep and slow wave sleep concomitant with reduced power between 8–16 Hz at the end of the biological night. Slow wave sleep and NREM sleep delta EEG activity covaried positively with overall working memory performance, independent of circadian phase and genotype. Moreover, REM sleep duration benefitted working memory particularly when occurring in the early morning hours and specifically in heterozygous individuals. Even though based on a small sample size and thus requiring replication, our results suggest genotype-dependent differences in circadian sleep regulation. They further indicate that REM sleep, being under strong circadian control, boosts working memory performance according to genotype in a time-of-day dependent manner. Finally, our data provide first evidence that slow wave sleep and NREM sleep delta activity, majorly regulated by sleep homeostatic mechanisms, is linked to working memory independent of the timing of the sleep episode within the 24-h cycle.
The neutron sensitivity of the C6D6 detector setup used at n_TOF facility for capture measurements has been studied by means of detailed GEANT4 simulations. A realistic software replica of the entire n_TOF experimental hall, including the neutron beam line, sample, detector supports and the walls of the experimental area has been implemented in the simulations. The simulations have been analyzed in the same manner as experimental data, in particular by applying the Pulse Height Weighting Technique. The simulations have been validated against a measurement of the neutron background performed with a natC sample, showing an excellent agreement above 1 keV. At lower energies, an additional component in the measured natC yield has been discovered, which prevents the use of natC data for neutron background estimates at neutron energies below a few hundred eV. The origin and time structure of the neutron background have been derived from the simulations. Examples of the neutron background for two different samples are demonstrating the important role of accurate simulations of the neutron background in capture cross-section measurements.
The neutron capture cross section of 58Ni was measured at the neutron time of flight facility n_TOF at CERN, from 27 meV to 400 keV neutron energy. Special care has been taken to identify all the possible sources of background, with the so-called neutron background obtained for the first time using high-precision GEANT4 simulations. The energy range up to 122 keV was treated as the resolved resonance region, where 51 resonances were identified and analyzed by a multilevel R-matrix code SAMMY. Above 122 keV the code SESH was used in analyzing the unresolved resonance region of the capture yield. Maxwellian averaged cross sections were calculated in the temperature range of kT = 5 – 100 keV, and their astrophysical implications were investigated.
Recent studies suggest that synaptic lysophosphatidic acids (LPAs) augment glutamate-dependent cortical excitability and sensory information processing in mice and humans via presynaptic LPAR2 activation. Here, we studied the consequences of LPAR2 deletion or antagonism on various aspects of cognition using a set of behavioral and electrophysiological analyses. Hippocampal neuronal network activity was decreased in middle-aged LPAR2−/− mice, whereas hippocampal long-term potentiation (LTP) was increased suggesting cognitive advantages of LPAR2−/− mice. In line with the lower excitability, RNAseq studies revealed reduced transcription of neuronal activity markers in the dentate gyrus of the hippocampus in naïve LPAR2−/− mice, including ARC, FOS, FOSB, NR4A, NPAS4 and EGR2. LPAR2−/− mice behaved similarly to wild-type controls in maze tests of spatial or social learning and memory but showed faster and accurate responses in a 5-choice serial reaction touchscreen task requiring high attention and fast spatial discrimination. In IntelliCage learning experiments, LPAR2−/− were less active during daytime but normally active at night, and showed higher accuracy and attention to LED cues during active times. Overall, they maintained equal or superior licking success with fewer trials. Pharmacological block of the LPAR2 receptor recapitulated the LPAR2−/− phenotype, which was characterized by economic corner usage, stronger daytime resting behavior and higher proportions of correct trials. We conclude that LPAR2 stabilizes neuronal network excitability upon aging and allows for more efficient use of resting periods, better memory consolidation and better performance in tasks requiring high selective attention. Therapeutic LPAR2 antagonism may alleviate aging-associated cognitive dysfunctions.
The production of Σ0 baryons in the nuclear reaction p (3.5 GeV) + Nb (corresponding to sNN=3.18 GeV) is studied with the detector set-up HADES at GSI, Darmstadt. Σ0s were identified via the decay Σ0→Λγ with subsequent decays Λ→pπ− in coincidence with a e+e− pair from either external (γ→e+e−) or internal (Dalitz decay γ⁎→e+e−) gamma conversions. The differential Σ0 cross section integrated over the detector acceptance, i.e. the rapidity interval 0.5<y<1.1, has been extracted as ΔσΣ0=2.3±(0.2)stat±(−0.6+0.6)sys±(0.2)norm mb, yielding the inclusive production cross section in full phase space σΣ0total=5.8±(0.5)stat±(−1.4+1.4)sys±(0.6)norm±(1.7)extrapol mb by averaging over different extrapolation methods. The Λall/Σ0 ratio within the HADES acceptance is equal to 2.3±(0.2)stat±(−0.6+0.6)sys. The obtained rapidity and momentum distributions are compared to transport model calculations. The Σ0 yield agrees with the statistical model of particle production in nuclear reactions. Keywords: Hyperons, Strangeness, Proton, Nucleus.
The design and operation of innovative nuclear systems requires a better knowledge of the capture and fission cross sections of the Pu isotopes. For the case of capture on 242Pu, a reduction of the uncertainty in the fast region down to 8-12% is required. Moreover, aiming at improving the evaluation of the fast energy range in terms of average parameters, the OECD NEA High Priority Request List (HPRL) requests high-resolution capture measurements with improved accuracy below 2 keV. The current uncertainties also affect the thermal point, where previous experiments deviate from each other by 20%. A fruitful collaboration betwen JGU Mainz and HZ Dresden-Rossendorf within the EC CHANDA project resulted in a 242Pu sample consisting of a stack of seven fission-like targets making a total of 95(4) mg of 242Pu electrodeposited on thin (11.5 μm) aluminum backings. This contribution presents the results of a set of measurements of the 242Pu(n, γ) cross section from thermal to 500 keV combining different neutron beams and techniques. The thermal point was determined at the Budapest Research Reactor by means of Neutron Activation Analysis and Prompt Gamma Analysis, and the resolved (1 eV - 4 keV) and unresolved (1 - 500 keV) resonance regions were measured using a set of four Total Energy detectors at the CERN n_TOF-EAR1.
The experimental area 2 (EAR-2) at CERNs neutron time-of-flight facility (n_TOF), which is operational since 2014, is designed and built as a short-distance complement to the experimental area 1 (EAR-1). The Parallel Plate Avalanche Counter (PPAC) monitor experiment was performed to characterize the beam pro↓le and the shape of the neutron 'ux at EAR-2. The prompt γ-flash which is used for calibrating the time-of-flight at EAR-1 is not seen by PPAC at EAR-2, shedding light on the physical origin of this γ-flash.
Der vorliegende Band dokumentiert die Erhebungsinstrumente der dritten Phase des BilWiss-Forschungsprogramms BilWiss-UV1 ("Ertrag und Entwicklung des universitären bildungswissenschaftlichen Wissens - Validierung eines Kompetenztests für Lehrkräfte") zu wissenschaftlichen Zwecken. Ziel dieser letzten Projektphase ist die Weiterentwicklung und Verbesserung des in den Vorgängerprojekten "BilWiss" und "BilWiss-Beruf" entwickelten Kompetenztests zur Erfassung des bildungswissenschaftlichen Wissens bei Lehramtsstudierenden und -absolvent(inn)en. Dieses Skalenhandbuch dokumentiert ausschlieÿlich den im Rahmen von BilWiss-UV erhobenen Studierendenlängsschnitt (LSII) der vorwiegend der Frage nachgeht, inwieweit sich bildungswissenschaftliches Wissen als Folge der Instruktion im Lehramtsstudium verändert. Ziel des Studierendenlängsschnittes ist es, eine Verteilung der Studierenden über den kompletten Studienverlauf abzubilden, da davon ausgegangen wird, dass je nach Fortschritt im Studium ein unterschiedlicher Bildungswissenschaftlicher Wissensstand zu erwarten ist. Das Projekt wird im Rahmen des BMBF-Förderprogramms "KoKoHS - Kompetenzmodelle und Instrumente der Kompetenzerfassung im Hochschulsektor-Validierung und methodische Innovationen" gefördert. Das Forschungsprogramm ist ein Verbundprojekt der Goethe-Universität Frankfurt (Prof. Dr. Mareike Kunter, Koordination), der Universität Duisburg-Essen (Prof. Dr. Detlev Leutner) sowie der Technischen Universität München (Prof. Dr. Tina Seidel). Das gesamte Programm zielt darauf ab, zu untersuchen, inwieweit angehende Lehrkräfte durch das Studium der Bildungswissenschaften unterstützt werden, mit den vielfältigen Herausforderungen ihres Berufs professionell umzugehen. Die zentrale Annahme dabei ist, dass konzeptuelles Wissen über bildungswissenschaftliche Inhalte die professionelle Entwicklung im Vorbereitungsdienst und im Berufseinstieg unterstützt. Die Grundhypothese des Projekts lautet: Bildungswissenschaftliche Inhalte und Zusammenhänge stellen einen begrifflichen Rahmen dar, den Lehrkräfte benötigen, um Unterrichts- und Schulereignisse angemessen zu interpretieren, zu reflektieren und so für die eigene Kompetenzentwicklung zu nutzen. Die in der Studie eingesetzten Instrumente sollen öffentlich für wissenschaftliche Zwecke zugänglich gemacht werden und sind vor allem als Hilfestellung für die Arbeit mit dem Längsschnittdatensatz anzusehen. Bereits veröffentlicht unter ISBN: 978-3-00-055380-6 finden Sie die Erhebungsinstrumente der Projektphasen des BilWiss-Forschungsprogramms von 2009-2016. Weiterführende Informationen zum theoretischen Ansatz der Studie und Ergebnissen der Studie können der Internetseite http://www.bilwiss.uni-frankfurt.de sowie den im Literaturverzeichnis aufgeführten Publikationen entnommen werden.
Der vorliegende Band dokumentiert die Erhebungsinstrumente der dritten Phase des BilWiss-Forschungsprogramms BilWiss-UV1 ("Ertrag und Entwicklung des universitären bildungswissenschaftlichen Wissens - Validierung eines Kompetenztests für Lehrkräfte"), zu wissenschaftlichen Zwecken. Das Projekt wird im Rahmen des BMBF-Förderprogramms "KoKoHS - Kompetenzmodelle und Instrumente der Kompetenzerfassung im Hochschulsektor-Validierung und methodische Innovationen" gefördert. Das Forschungsprogramm ist ein Verbundprojekt der Goethe-Universität Frankfurt (Prof. Dr. Mareike Kunter, Koordination), der Universität Duisburg-Essen (Prof. Dr. Detlev Leutner) sowie der Technischen Universität München (Prof. Dr. Tina Seidel). Das gesamte Programm zielt darauf ab, zu untersuchen, inwieweit angehende Lehrkräfte durch das Studium der Bildungswissenschaften unterstützt werden, mit den vielfältigen Herausforderungen ihres Berufs professionell umzugehen. Die zentrale Annahme dabei ist, dass konzeptuelles Wissen über bildungswissenschaftliche Inhalte die professionelle Entwicklung im Vorbereitungsdienst und im Berufseinstieg unterstützt. Die Grundhypothese des Projekts lautet: Bildungswissenschaftliche Inhalte und Zusammenhänge stellen einen begrifflichen Rahmen dar, den Lehrkräfte benötigen, um Unterrichts- und Schulereignisse angemessen zu interpretieren, zu reflektieren und so für die eigene Kompetenzentwicklung zu nutzen. Für die seit 2009 bestehende Längsschnittstichprobe der Vorgängerprojekte BilWiss und BilWiss-Beruf fand Mitte des Jahres 2017 der fünfte MZP statt. Alle Teilnehmer(innen), die sich zur Teilnahme an weiteren Befragungen bereit erklärt hatten, wurden per Email kontaktiert und zur Teilnahme an der Onlineumfrage eingeladen. Es konnten 136 Personen erneut befragt werden, davon sind 124 derzeit aktiv als Lehrkraft im Schuldienst tätig (120 Lehrkräfte in Vollzeit). Im Rahmen des fünften Messzeitpunktes wurde neben Fragebogenskalen zum professionellen Verhalten, auch die im Rahmen von Meilenstein 3 entwickelte Verhaltenscheckliste eingesetzt. Durch deren Einsatz konnte ermittelt werden, dass nahezu alle der befragten Lehrkräfte Sonderfunktionen im Schuldienst übernehmen. Um einige wenige Beispiele herauszugreifen: Es sind 7 befragte Lehrkräfte in der Stufenkoordination beschäftigt, 111 Lehrer(innen) sind Klassenleitung. Als Mentor(in) engagieren sich 34 Personen und ebenfalls 34 Lehrer(innen) kooperieren mit außerschulischen Partnern. Die Durchführung des Observers wurde vom Standort München administriert und betreut. Ende des Jahres 2018 fand schlieÿlich der sechste und letzte Messzeitpunkt als Onlineerhebung statt. Bei der Bearbeitung standen neben der aktuellen beruflichen Situation auch das Erleben und das professionelle Verhalten im Lehrerberuf im Fokus. Zur Erfassung der Professional Vision in Elternberatungssituationen wurde das in 2017 entwickelte Videotool eingesetzt. Ergänzend wurde der Szenariotest zur Elternberatungskompetenz in einer Kurzversion eingesetzt (Bruder, Keller, Klug & Schmitz, 2011). Zur Erfassung des proaktiven Engagements in der Schulentwicklung wurde auch bei diesem Messzeitpunkt die Verhaltenscheckliste eingesetzt. Zur Erfassung der diagnostischen Kompetenz wurde ein neu entwickelter Vignetten-Test eingesetzt. Insgesamt konnten im Online-Fragebogen (inkl. Videotool, Szenariotest, Verhaltenscheckliste und diagnostischen Fallvignetten) 68 Personen befragt werden, davon sind 56 derzeit aktiv als Lehrkraft im Schuldienst tätig (51 Lehrkräfte in Vollzeit). Die in der Studie eingesetzten Instrumente sollen öffentlich für wissenschaftliche Zwecke zugänglich gemacht werden und sind vor allem als Hilfestellung für die Arbeit mit dem Längsschnittdatensatz anzusehen. Bereits veröffentlicht unter ISBN: 978-3-00-055380-6 finden Sie die Erhebungsinstrumente der Projektphasen des BilWiss-Forschungsprogramms von 2009-2016. Weiterführende Informationen zum theoretischen Ansatz der Studie und Ergebnissen der Studie können der Internetseite http://www.bilwiss.uni-frankfurt.de sowie den im Literaturverzeichnis aufgeführten Publikationen entnommen werden.
Plants, fungi and algae are important components of global biodiversity and are fundamental to all ecosystems. They are the basis for human well-being, providing food, materials and medicines. Specimens of all three groups of organisms are accommodated in herbaria, where they are commonly referred to as botanical specimens.The large number of specimens in herbaria provides an ample, permanent and continuously improving knowledge base on these organisms and an indispensable source for the analysis of the distribution of species in space and time critical for current and future research relating to global biodiversity. In order to make full use of this resource, a research infrastructure has to be built that grants comprehensive and free access to the information in herbaria and botanical collections in general. This can be achieved through digitization of the botanical objects and associated data.The botanical research community can count on a long-standing tradition of collaboration among institutions and individuals. It agreed on data standards and standard services even before the advent of computerization and information networking, an example being the Index Herbariorum as a global registry of herbaria helping towards the unique identification of specimens cited in the literature.In the spirit of this collaborative history, 51 representatives from 30 institutions advocate to start the digitization of botanical collections with the overall wall-to-wall digitization of the flat objects stored in German herbaria. Germany has 70 herbaria holding almost 23 million specimens according to a national survey carried out in 2019. 87% of these specimens are not yet digitized. Experiences from other countries like France, the Netherlands, Finland, the US and Australia show that herbaria can be comprehensively and cost-efficiently digitized in a relatively short time due to established workflows and protocols for the high-throughput digitization of flat objects.Most of the herbaria are part of a university (34), fewer belong to municipal museums (10) or state museums (8), six herbaria belong to institutions also supported by federal funds such as Leibniz institutes, and four belong to non-governmental organizations. A common data infrastructure must therefore integrate different kinds of institutions.Making full use of the data gained by digitization requires the set-up of a digital infrastructure for storage, archiving, content indexing and networking as well as standardized access for the scientific use of digital objects. A standards-based portfolio of technical components has already been developed and successfully tested by the Biodiversity Informatics Community over the last two decades, comprising among others access protocols, collection databases, portals, tools for semantic enrichment and annotation, international networking, storage and archiving in accordance with international standards. This was achieved through the funding by national and international programs and initiatives, which also paved the road for the German contribution to the Global Biodiversity Information Facility (GBIF).Herbaria constitute a large part of the German botanical collections that also comprise living collections in botanical gardens and seed banks, DNA- and tissue samples, specimens preserved in fluids or on microscope slides and more. Once the herbaria are digitized, these resources can be integrated, adding to the value of the overall research infrastructure. The community has agreed on tasks that are shared between the herbaria, as the German GBIF model already successfully demonstrates.We have compiled nine scientific use cases of immediate societal relevance for an integrated infrastructure of botanical collections. They address accelerated biodiversity discovery and research, biomonitoring and conservation planning, biodiversity modelling, the generation of trait information, automated image recognition by artificial intelligence, automated pathogen detection, contextualization by interlinking objects, enabling provenance research, as well as education, outreach and citizen science.We propose to start this initiative now in order to valorize German botanical collections as a vital part of a worldwide biodiversity data pool.
Knowledge is limited as to how prior SARS-CoV-2 infection influences cellular and humoral immunity after booster-vaccination with bivalent BA.4/5-adapted mRNA-vaccines, and whether vaccine-induced immunity correlates with subsequent infection. In this observational study, individuals with prior infection (n=64) showed higher vaccine-induced anti-spike IgG antibodies and neutralizing titers, but the relative increase was significantly higher in non-infected individuals (n=63). In general, both groups showed higher neutralizing activity towards the parental strain than towards Omicron subvariants BA.1, BA.2 and BA.5. In contrast, CD4 or CD8 T-cell levels towards spike from the parental strain and the Omicron subvariants, and cytokine expression profiles were similar irrespective of prior infection. Breakthrough infections occurred more frequently among previously non-infected individuals, who had significantly lower vaccine-induced spike-specific neutralizing activity and CD4 T-cell levels. Thus, the magnitude of vaccine-induced neutralizing activity and specific CD4 T-cells after bivalent vaccination may serve as a correlate for protection in previously non-infected individuals.