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Conventional treatments for mood disorders primarily focus on reducing negative affect, but little on enhancing positive affect. Loving-kindness meditation (LKM) is a traditional meditation practice directly oriented toward enhancing unconditional and positive emotional states of kindness towards oneself and others. We report here two independent and uncontrolled studies carried out at different centers, one in Boston, USA (n = 10), and one in Frankfurt, Germany (n = 8), to examine the potential therapeutic utility of a brief LKM group intervention for symptoms of dysthymia and depression. Results at both centers suggest that LKM was associated with large-sized effects on self-reported symptoms of depression (d = 3.33 and 1.90), negative affect (d = 1.98 and 0.92), and positive affect (d = 1.63 and 0.94). Large effects were also found for clinician-reported changes in depression, rumination and specific positive emotions, and moderate effects for changes in adaptive emotion regulation strategies. The qualitative data analyses provide additional support for the potential clinical utility of the intervention. This proof-of-concept evaluation of LKM as a clinical strategy warrants further investigation.
Am vergangenen Freitag stimmte der Bundestag mit deutlicher Mehrheit für einen Einsatz der Bundeswehr im Kampf gegen den sogenannten Islamischen Staat. Bereits am Donnerstag veröffentlichten die Fachschaften der Friedens- und Konfliktforschungs-Studiengänge in Frankfurt, Magdeburg, Marburg und Tübingen eine Stellungnahme in der sie erläutern, weshalb ein überstürztes Eingreifen in Syrien falsch sei. Inzwischen wird die Erklärung auch von anderen Studierenden, Lehrenden sowie Professorinnen und Professoren der Friedens- und Konfliktforschung unterstützt. Hier die Kernpunkte deS Statements:...
Seit einem Jahr ist im Umfeld der Vereinten Nationen immer wieder von einem „Human Rights Up Front Aktionsplan“ zu hören. Erst kürzlich forderte Generalsekretär Ban Ki-moon die Mitgliedstaaten in einer Ansprache zu den Prioritäten der UN 2015 auf den Aktionsplan zu unterstützen. Doch was ist das für eine Initiative und welche Resultate hat sie bislang hervorgebracht? Diesen Fragen geht dieser Beitrag auf den Grund.
Ein Crosspost aus dem äußerst lesenswerten neuen Blog der Friedensakademie Rheinland-Pfalz friedensakademie-blog.eu/ zur aktuellen Lage in Libyen: Dort droht die internationale Staatengemeinschaft vier Jahre nach der Intervention in ihrer Verantwortung zur Prävention eines weiteren Blutvergießens zu scheitern. Mein Originalbeitrag beim Friedensakademie-Blog erschien am 6. Februar 2015.
Some are arguing that the the Responsibility to Protect, an international norm that aims to prevent mass atrocities, was faltering, because of its abuse in Libya and its non-application in Syria. However, Gregor Hofmann argues in this cross-post from the ICRtoP-Blog that the critics' interpretation was limiting R2P to its interventionist aspects. If one looks at the whole set of norms that is included in R2P, it becomes apparent that R2P is under pressure, but not yet death...
Völkermord an den Armeniern: diplomatische Rücksichtnahme darf Anerkennung nicht im Weg stehen
(2015)
In ihrem Gastbeitrag fordern Matthias Winkler und Timo Leimeister von Genocide Alert, dass Deutschland, trotz möglicher diplomatischer Verstimmungen, nicht davor zurückschrecken sollte, den Völkermord an den Armeniern von 1915 als solchen ausdrücklich zu benennen. Vor einem Jahrhundert wurden weite Teile des armenischen Volkes im Osmanischen Reich in einem Völkermord ausgelöscht. Das Deutsche Reich war ein enger Verbündeter der damaligen osmanischen Regierung und stellte die Bündnispolitik über das Überleben der Armenier. Durch ein Eingeständnis auch der eigenen historischen Verantwortung an den Geschehnissen kann die Bundesrepublik im Gegenteil den Vertretern einer Aussöhnung in der Türkei den Rücken stärken...
Auch wenn seit George W. Bushs „War on Terror“ die Bekämpfung von Terrorismus nicht mehr ohne fragwürdigen Beigeschmack mit dem Begriff des „Krieges“ bezeichnet werden kann, erlebt eine derartige Rhetorik zusammen mit dem Aufstieg des Islamischen Staates ein neues Revival. Während zunächst Papst Franziskus von einem „Dritten Weltkrieg“ sprach, assistierten nach den jüngsten Anschlägen in Frankreich und Sousse auch deutsche Medien bei der Konstruktion solch umfassender Bedrohungsszenarien. Selbst der Präsident des Bundesamtes für Verfassungsschutz, Hans-Georg Maaßen, sieht mittlerweile einen „terroristischen Weltkrieg“ ausgebrochen. Lässt man einmal die zahlreichen Gründe beiseite, warum eine derartige Bezeichnung im besten Fall falsch und im schlimmsten Fall kontraproduktiv ist 1, so kann man derlei Aussagen als Ausdruck einer Gefahrenwahrnehmung interpretieren, aus der nicht zuletzt eine gefühlte Hilflosigkeit angesichts der terroristischen Bedrohung von immer mehr Lebensbereichen spricht. Auf Flugreisen, auf dem Weg zur Arbeit, bei der Arbeit, bei Sportveranstaltungen: die Orte gefühlter Sicherheit werden zunehmend weniger. Und nun ist selbst ein Strandurlaub nicht mehr frei vom Risiko, einen gewaltsamen Tod zu sterben...
Stimulation of a principal whisker yields sparse action potential (AP) spiking in layer 2/3 (L2/3) pyramidal neurons in a cortical column of rat barrel cortex. The low AP rates in pyramidal neurons could be explained by activation of interneurons in L2/3 providing inhibition onto L2/3 pyramidal neurons. L2/3 interneurons classified as local inhibitors based on their axonal projection in the same column were reported to receive strong excitatory input from spiny neurons in L4, which are also the main source of the excitatory input to L2/3 pyramidal neurons. Here, we investigated the remaining synaptic connection in this intracolumnar microcircuit. We found strong and reliable inhibitory synaptic transmission between intracolumnar L2/3 local-inhibitor-to-L2/3 pyramidal neuron pairs [inhibitory postsynaptic potential (IPSP) amplitude -0.88 ± 0.67 mV]. On average, 6.2 ± 2 synaptic contacts were made by L2/3 local inhibitors onto L2/3 pyramidal neurons at 107 ± 64 µm path distance from the pyramidal neuron soma, thus overlapping with the distribution of synaptic contacts from L4 spiny neurons onto L2/3 pyramidal neurons (67 ± 34 µm). Finally, using compartmental simulations, we determined the synaptic conductance per synaptic contact to be 0.77 ± 0.4 nS. We conclude that the synaptic circuit from L4 to L2/3 can provide efficient shunting inhibition that is temporally and spatially aligned with the excitatory input from L4 to L2/3.
Our paper evaluates recent regulatory proposals mandating the deferral of bonus payments and claw-back clauses in the financial sector. We study a broadly applicable principal agent setting, in which the agent exerts effort for an immediately observable task (acquisition) and a task for which information is only gradually available over time (diligence). Optimal compensation contracts trade off the cost and benefit of delay resulting from agent impatience and the informational gain. Mandatory deferral may increase or decrease equilibrium diligence depending on the importance of the acquisition task. We provide concrete conditions on economic primitives that make mandatory deferral socially (un)desirable.
Immersion freezing is the most relevant heterogeneous ice nucleation mechanism through which ice crystals are formed in mixed-phase clouds. In recent years, an increasing number of laboratory experiments utilizing a variety of instruments have examined immersion freezing activity of atmospherically relevant ice-nucleating particles. However, an intercomparison of these laboratory results is a difficult task because investigators have used different ice nucleation (IN) measurement methods to produce these results. A remaining challenge is to explore the sensitivity and accuracy of these techniques and to understand how the IN results are potentially influenced or biased by experimental parameters associated with these techniques.
Within the framework of INUIT (Ice Nuclei Research Unit), we distributed an illite-rich sample (illite NX) as a representative surrogate for atmospheric mineral dust particles to investigators to perform immersion freezing experiments using different IN measurement methods and to obtain IN data as a function of particle concentration, temperature (T), cooling rate and nucleation time. A total of 17 measurement methods were involved in the data intercomparison. Experiments with seven instruments started with the test sample pre-suspended in water before cooling, while 10 other instruments employed water vapor condensation onto dry-dispersed particles followed by immersion freezing. The resulting comprehensive immersion freezing data set was evaluated using the ice nucleation active surface-site density, ns, to develop a representative ns(T) spectrum that spans a wide temperature range (−37 °C < T < −11 °C) and covers 9 orders of magnitude in ns.
In general, the 17 immersion freezing measurement techniques deviate, within a range of about 8 °C in terms of temperature, by 3 orders of magnitude with respect to ns. In addition, we show evidence that the immersion freezing efficiency expressed in ns of illite NX particles is relatively independent of droplet size, particle mass in suspension, particle size and cooling rate during freezing. A strong temperature dependence and weak time and size dependence of the immersion freezing efficiency of illite-rich clay mineral particles enabled the ns parameterization solely as a function of temperature. We also characterized the ns(T) spectra and identified a section with a steep slope between −20 and −27 °C, where a large fraction of active sites of our test dust may trigger immersion freezing. This slope was followed by a region with a gentler slope at temperatures below −27 °C. While the agreement between different instruments was reasonable below ~ −27 °C, there seemed to be a different trend in the temperature-dependent ice nucleation activity from the suspension and dry-dispersed particle measurements for this mineral dust, in particular at higher temperatures. For instance, the ice nucleation activity expressed in ns was smaller for the average of the wet suspended samples and higher for the average of the dry-dispersed aerosol samples between about −27 and −18 °C. Only instruments making measurements with wet suspended samples were able to measure ice nucleation above −18 °C. A possible explanation for the deviation between −27 and −18 °C is discussed. Multiple exponential distribution fits in both linear and log space for both specific surface area-based ns(T) and geometric surface area-based ns(T) are provided. These new fits, constrained by using identical reference samples, will help to compare IN measurement methods that are not included in the present study and IN data from future IN instruments.
We show that the size of collateralized household debt determines an economy’s vulnerability to crises of confidence. The house price feeds back on itself by contributing to a liquidity effect, which operates through the value of housing in a collateral constraint. Over a specific range of debt levels this liquidity feedback effect is strong enough to give rise to multiplicity of house prices. In a dynamic setup, we conceptualize confidence as a realization of rationally entertainable belief-weightings of multiple future prices. This delivers debt-level-dependent bounds on the extent to which confidence may drive house prices and aggregate consumption.
Flüchtlinge, Schuldenkrise, Diskriminierung. Drei hochaktuelle, weltumspannende Themen, die eines verbindet: die Frage nach Gerechtigkeit. An der Goethe-Universität denkt die Forschergruppe »Justitia Amplificata: Erweiterte Gerechtigkeit – konkret und global« über Gerechtigkeitstheorien nach. Die Gruppe untersucht Theorien der Gerechtigkeit und ihre praktischen Implikationen. Die Deutsche Forschungsgemeinschaft fördert die Arbeit der interdisziplinärangelegten Kolleg- Forschergruppe. Diese vernetzt Wissenschaftlerinnen und Wissenschaftler unterschiedlicher Karrierestufen.
Chemistry and time
(2015)
Die Relevanz von MSC aus Fettgewebe (ASC) in der regenerativen Medizin überrascht in Anbetracht ihrer breit gefächerten Eigenschaften nicht. Neben antiinflammatorischen Eigenschaften und Hypoxieresistenz können sie in eine Vielzahl von Geweben differenzieren und in geschädigtes Gewebe migrieren, wo sie an Reperaturvorgängen beteiligt sind. Dabei stehen unterschiedliche Quellen zur Isolierung von MSC (und ASC) zur Verfügung. Um ASC therapeutisch einsetzen zu können, ist es essentiell ihre Quellen und ihr Potenzial zu erforschen. Es konnte gezeigt werden, dass perirenales Fettgewebe eine geeignete Quelle für ASC (prASC) darstellt. Der Nachweis der Oberflächenantigene CD73, CD90 und CD105 mittels Durchflusszytometrie sowie die Fähigkeit der prASC an Zellkulturplastik zu adhärieren, erlauben die Schlussfolgerung, dass es sich bei den nach einem bereits etablierten Verfahren isolierten Zellen um MSC handelt. Außerdem konnte durch eine zweiwöchige Kultivierung der prASC in supplementierten Medien die Differenzierung in Adipozyten, Chondrozyten sowie Osteozyten induziert werden. Der Nachweis erfolgte durch cytochemische Färbemethoden. In dieser Arbeit wurde die Differenzierung von prASC in Epithelzellen untersucht. Dafür wurden die Zellen in unterschiedlichen ATRA-haltigen Kulturmedien und konditioniertem Medium aus Tubulusepithelzellen kultiviert. Der Einfluss der Medien wurde mittels Western Blot, qPCR und Immunfluoreszenzfärbung nachgewiesen. Die Kultivierung mit ATRA führte zu einer signifikanten Erhöhung der Expression von CK18 und ZO-1. Dabei handelt es sich um Marker, die charakteristisch für Epithelzellen sind. Es konnte folglich gezeigt werden, dass humane prASC in vitro eindeutig in epithelialer Richtung differenzieren können. Unter dem Einfluss von ATRA-supplementierten Medien exprimierten die kultivierten Zellen Genprodukte, die Epithelzellen zuzuordnen sind.
Welche Bedeutung diese Erkenntnis hat ist noch unklar. Möglicherweise sind prASC, als Stammzellen aus Nischen mit anatomischer Nähe zu den Nieren, potente Kandidaten, um untergegangenes Nierengewebe, wie beispielsweise Tubulusepithelzellen, zu ersetzen.
Es geht um eine spezielle Auseinandersetzung mit dem Sachunterricht der hessischen Grundschule. Ziel eines Projektes („IGEL“ - Individuelle Förderung und adaptive Lern-Gelegenheiten in der Grundschule) des Frankfurter IDeA-Zentrums war es, das pädagogische Handeln von Lehrkräften zu verändern. Wir folgen diesem Versuch anhand dreier Lehrerinnen, die von Projektseite in der Methode der „Kognitiven Strukturierung“ fortgebildet wurden und die diese Methode im Rahmen einer standardisierten Unterrichtseinheit zum „Schwimmen und Sinken“ erproben sollen. Zu diesem Zweck führen wir Fallanalysen von Sachunterrichtsstunden vor und nach der Fortbildung derselben Lehrkräfte durch, sowie detaillierte didaktische Analysen des jeweils eingesetzten Materials. Wir kommen zu differenzierten kritischen Schlüssen. Das pädagogische und insbesondere das didaktische Handeln der Lehrerinnen wird in Folge der Fortbildungen stark perturbiert; zu der beabsichtigten und in Form von Handreichungen vorgegebenen „Kognitiven Strukturierung“ auf Schülerseite kommt es indes nicht. Stattdessen studieren wir intensiv die Überforderung der Lehrerinnen, die aus einer Kombination von a. den fachwissenschaftlichen Hintergründen, b. der freiwilligen Verpflichtung zur Manualumsetzung und c. den artikulierten Bedürfnissen der Schüler resultiert. Wir können anhand des Versuchs, die Lehrpersonen in „Kognitiver Strukturierung“ fortzubilden, einen Blick auf deren eigene kognitive und pädagogische Strukturen werfen; eine kontrollierte Eingriffnahme in diese Strukturen jedoch findet im Rahmen der „Implementationen“ nicht statt. Die Interventionsform der randomisierten Nachmittagsfortbildung wird zwar verworfen, lediglich angerissen aber die Frage, wie das erlangte Wissen zu nutzen wäre.
Objective: Cognitive models suggest that the self-concept of persons with psychosis can be fundamentally affected. Self-concepts were found to be related to different symptom domains when measured concurrently. Longitudinal investigations to disentangle the possible causal associations are rare.
Method: We examined a sample of 160 people with a diagnosis of schizophrenia who took part in a psychotherapy study. All participants had the DSM-IV diagnosis of a schizophrenia and pronounced negative symptoms. Neurocognition, symptoms, and self-concepts were assessed at two time points 12 months apart. Structural equation modeling was used to test whether symptoms influence self-concepts (scar-model) or self-concepts affect symptoms (vulnerability model).
Results: Negative symptoms correlated concurrently with self-concepts. Neurocognitive deficits are associated with more negative self-concepts 12 months later. Interpersonal self-concepts were found to be relevant for paranoia.
Conclusion: The findings implicate that if deficits in neurocognition are present, fostering a positive self-concept should be an issue in therapy. Negative interpersonal self-concept indicates an increased risk for paranoid delusions in the course of 1 year. New aspects for cognitive models in schizophrenia and clinical implications are discussed.
Amphibians have existed on the planet for over 300 million years and are today one of the most diverse vertebrate classes in the world with over 7000 known species and still many more to be discovered. However, several studies assume that approximately one third of the world´s known living amphibians are directly threatened with extinction, making it the most endangered vertebrate class. In relation to the relatively small land mass that is occupied by the state of Panama, it supports one of the most diverse amphibian faunas. However, in many cases the ecological role of single species in a wider context and their habitat preferences are still poorly understood and subject to ongoing research. Modern taxonomic approaches in other tropical regions have shown that former assumptions of amphibian diversity were distinct underestimations of the actual species diversity; a situation that is probably also true for Panama. Concurrently, the collection of amphibian diversity data and the description of new species is a race against time. The amphibian fauna of the world and that of Panama in particular, has suffered from an unprecedented loss of diversity over the last 30 years. The reasons are manifold and include destruction, alteration, and fragmentation of their natural habitats as the main causes, but also the deadly amphibian disease chytridiomycosis caused by the fungal pathogen Batrachochytrium dendrobatidis (Bd). In Panama and Costa Rica, this Emerging Infectious Disease (EID) spread in a wave-like manner from west to east causing mass die-offs and reduced amphibian diversity even in well-preserved habitats. The disease has primarily affected stream-associated highland species. The last large-scale evaluation of the conservation status of Panama´s amphibians through the IUCN Red List of Threatened Species in 2004 concluded that approximately 30% of the known species are acutely threatened with extinction. Furthermore, around 17% of the amphibian species that have been known back then lacked adequate data to be assessed. In view of Panama´s already overwhelming amphibian diversity, as well as the variety of habitats and the large number of sites that have not been examined with regard to amphibians before, I started this study with the conviction that the inventory of Panama´s amphibian diversity is far from being completed. Furthermore, when I started this study, it was uncertain if there would be any surviving amphibian species in areas where chytridiomycosis had emerged. The loss of whole amphibian communities in upland western Panama following Bd arrival led to a shift of amphibian research to lowland sites in central and eastern Panama aiming primarily on pathogen arrival and the documentation of epizootic outbreak and subsequent population decline. The situation of amphibian communities in areas post-decline was therefore largely unknown. Accordingly, the main goals of my study were to add to the taxonomic inventory of amphibians in Panama and to assess the situation of amphibian populations in habitats where chytrid-driven declines have been observed. To address these tasks I conducted fieldwork in western Panama with a focus on mountainous elevations between 1000 and 3475 m asl. Additionally, I visited different lowland sites between sea level and 1000 m asl to collect comparative material. In the period between 2008 and 2013, I conducted five collection trips to Panama that add up to a total of approximately 13 months in the field. I have sampled nine regions in western Panama and collected 767 specimens together with student collaborators, 531 of which were collected under my personal field number. Additional data obtained from those specimens include 68 male anuran call recordings, 102 standardized color descriptions of specimens in life, and 259 tissue samples that to date yielded 185 16S mtDNA sequences. This comprises the most comprehensive data set for amphibians of Panama and the first large-scale DNA barcoding approach for western Panama to date. After a preliminary DNA barcoding and subsequent comparative examination of morphological und bioacoustic data of all specimens collected, the number of taxonomic problems that needed to be addressed was higher than I previously anticipated. For most genetic lineages deeper taxonomic analyses were required to reach conclusive results. A selection had to be made with which lineages to proceed in the analyses, in view of the substantial financial and time expenditure that would be needed for a complete taxonomic revision. Therefore, I chose to run deeper analyses on one genus from each of the three amphibian orders in Panama. The genera selection depended largely on the availability of sufficient material and the scientific relevance of the respective genus.
I selected the genus Diasporus from the order Anura. These small frogs are omnipresent in many habitats and thus relatively easy to find. In addition, the genus is underrepresented in taxonomic studies. This is the first taxonomic study on the genus Diasporus to include a molecular phylogeny and the first comparison of advertisement calls between several populations from western Panama. In total, I collected 67 Diasporus specimens throughout western Panama and compared them morphologically with 49 additional specimens from Central America in collections, including the primary types of D. diasporus and D. hylaeformis. Additional comparative data were taken from literature. The DNA barcoding analysis of a fragment of the 16S rRNA gene included 43 own sequences that were complemented with 15 relevant GenBank sequences. In addition, I compared the advertisement calls of 26 male individuals among each other and with call descriptions from the literature. The DNA barcoding approach revealed several unnamed genetic lineages, but in some cases also resulted in the lumping of morphologically and bioacoustically distinct specimens. Generally, the morphological examination of the collected material revealed almost no specific characters that could be used to distinguish between genetic lineages. However, it was possible to identify species using a combination of several morphological characteristics. Which ones are relevant in the individual case depends on the respective species. My extensive collection of call recordings made it possible to test for the first time the intraspecific call variation of D. hylaeformis in dependency of various parameters. This analysis showed that the dominant frequency depends significantly on the body size of the calling male; the smaller the calling male, the higher the frequency of the call. A similar relationship was observed between the call rate and temperature: the lower the temperature during calling, the lower the call rate. I suppose that these general patterns, which have already been observed in other anuran genera, are also true in other Diasporus species that could not be tested in this study. Taking into account the intraspecific variation of Diasporus advertisement calls, I consider comparative call analyses to be the best way to distinguish between species. This is especially true in syntopic species. Integration of the three lines of evidence (i.e., morphology, DNA barcoding, and bioacoustics) led to the identification of four new species, two of which (i.e., D. citrinobapheus and D. igneus) colleagues and I have already formally described.
I conducted an integrative taxonomic analysis of the western Panamanian representatives of the genus Bolitoglossa from the order Caudata, the larger of the two Panamanian salamander genera. Bolitoglossa is very species-rich with a centre of diversification in the high mountains of Costa Rica and western Panama. I collected 53 Bolitoglossa specimens and compared them to twelve specimens in collection, including the holotype and one paratype of B. gomezi. The dataset was complemented with information from the literature. Among the sampled specimens were two species considered to be endangered that have not been collected or observed for several decades; B. magnifica has not been seen for 34 years and B. anthracina has not been seen for 22 years. Further, I collected salamanders at several new locations. To date, my 16S mtDNA barcoding analysis represents the densest taxon sampling for Panamanian Bolitoglossa composed of 21 own sequences that were combined in the final alignment with 47 GenBank sequences. Even though the molecular phylogeny is based only on a single marker, the received trees largely coincide with previous studies and the nodes received high statistical support. In these trees, I retrieve all previously defined subgenera and species groups. On the basis of this molecular phylogeny, I placed B. anthracina, here sequenced for the first time, in the B. subpalmata species group. Due to the fact that B. anthracina is a large and dark colored species it had previously been placed by implication in the B. schizodactyla species group along with other large black salamanders of the B. nigrescens species complex. Moreover, I found deep divergent genetic lineages among geographically separated populations of B. minutula. However, until now there were no additional morphological characteristics detectable to distinguish between these lineages. Additionally, my colleagues and I described a new deep divergent lineage in the B. robinsoni species group as B. jugivagans, a species new to science. In contrast, I found only minor genetic differences between specimens of B. sombra and B. nigrescens. After combining morphometric data and tooth counts from literature of both species with additional data from specimens of B. sombra that I collected near the type locality, the distinguishing features blurred. In particular, including much larger specimens of B. sombra, not yet known at the time of its description, showed that the tooth count difference is dependent on the size and age of the specimen examined. Larger specimens have more maxillary and vomerine teeth. Based on this evidence I regard B. sombra as a junior synonym of B. nigrescens. Further, I revised the Panamanian distribution of the two relatively common lowland salamanders, B. colonnea and B. lignicolor. Besides filling the gaps in the fragmentary known distributions of these species, I assessed the molecular and morphological variation of both species among populations in Panama. While there was little variation in B. lignicolor, I found divergent genetic lineages among geographically distinct populations of B. colonnea that require further taxonomic examination.
Caecilians (order Gymnophiona) are among the least investigated terrestrial vertebrates. After I received a first specimen of the predominantly South American genus Oscaecilia (family Caeciliidae) in western Panama, I started to work more extensively on the taxonomy of Caeciliidae in Central America. The specimens from western Panama were not readily assignable to a single described species, but shared characters with O. elongata and O. osae. While O. osae was only known from the holotype, the type material of O. elongata was destroyed during World War II. On the basis of the original description, the unique feature in O. elongata within Oscaecilia is the absence of subdermal scales in the posterior part of the body. In a referred specimen of O. elongata mentioned in the original description from eastern Panama, this characteristic cannot be examined as it consists of head and neck only. Therefore, I used non-destructive high-resolution, synchrotron-based X-ray micro CT imaging (HRμCT) to examine cranial characters in the specimens in question and took normal radiographs to count vertebrae and to make subdermal scales visible. I found that the fragmented specimen from eastern Panama likely belongs to the well-sampled species O. ochrocephala and has not much in common with O. osae or the specimens from western Panama. Contrarily, O. osae and the specimens from western Panama share many morphological characters, but also show some differences. Genetic barcoding revealed that both species are close relatives, but the genetic distance could not be finally resolved, because 16S sequences obtained from blood samples of living O. osae were of poor quality. Thus, I compare the Oscaecilia from western Panama to O. osae in this study, but postpone a taxonomic decision until further material becomes available. Further, I designate O. elongata a nomen dubium, because the type material is lost, the type locality is not defined in more detail than “Panama”, and the original description does not allow for a definite assignment. Since previous molecular studies only considered O. ochrocephala, the monophyly of Oscaecilia was never tested before. So far, the genus Oscaecilia is based largely on a single cranial character, the eyes covered with bone. Here, I combined two 16S mtDNA sequences of O. osae from Costa Rica and two sequences from O. sp. from western Panama with two sequences of O. ochrocephala and ten sequences of four species of the genus Caecilia, the sister genus of Oscaecilia. The resulted phylogeny contains two well-supported clades, one clade containing two species of Caecilia, one from Panama and one from western Ecuador and all species of Oscaecilia tested. The other clade consists of two species of Caecilia from the Amazon basin. I therefore assume that the split in both clades is due to the rise of the Andes, what led to today’s cis-trans-Andean distribution of the two clades. For now, to restore monophyly, I suggest to place Oscaecilia within the synonymy of Caecilia until more taxa have been tested. When assessing the conservation status of the amphibian species in mountainous western Panama, I first compiled a list of known species that I potentially could have found during my fieldwork. Using the IUCN categories, I analyzed how many of the endangered species I actually found and how these are distributed over families and species groups. Surprisingly, my rediscoveries of lost species were not equally distributed among the four families that comprise most endangered amphibian species (i.e., Bufonidae, Craugastoridae, Hylidae, and Plethodontidae). While I discovered ten of eleven endangered hylids and six of nine endangered plethodontids, I found only one of four endangered bufonids and none of the nine endangered craugastorids. I assume that the secretive living plethodontids, for which no Bd related declines have been documented, were just overlooked in the past decades. In contrast, I propose that hylids, in which Bd related population decline is well documented, developed distinct evolutionary solutions permitting coexistence with the pathogen. The situation is obviously different in bufonids and craugastorids, where I found no signs of population recoveries at present. So far, the only surviving populations of species from these families exist in climatic or physiographic niches that have probably shielded them from Bd. My data confirm the current view that the risk for naïve amphibian populations to decline during Bd epizootics is predicted by ecological traits (e.g., aquatic index, vertical distribution) and not dependent on taxonomic affiliation. However, I propose that only certain amphibian families (e.g., hylids and centrolenids) have the ability to acquire immunity solutions to coexist with the pathogen during enzootic stages. This is a very new perspective on the worst infectious disease in amphibians worldwide, allowing for new research approaches to understand the host-pathogen dynamics. Moreover, I examined where the share of surviving endangered amphibian species is particularly high in mountainous western Panama. As was to be expected, most of the endangered species are found within the boundaries of protected areas. One exception is the unprotected Cerro Colorado region in the Comarca Ngöbe-Buglé that provides habitat for a wide variety of endangered and undiscovered amphibian species. Nonetheless, planned open pit mining would destroy the forests in a large part of the area. This demonstrates once again that human activities are the biggest threat to amphibians in Panama and elsewhere.
"Vortreffliche Belichtung!" : die Erfindung des Oberlichts und der Weg zum modernen Kunstmuseum
(2015)
Der Umgang mit Licht ist beim Kuratieren von Ausstellungen und Sammlungspräsentationen von zentraler Bedeutung. Welchen Status erhalten die Exponate, welche Position nehmen sie innerhalb des Raums ein? Werden nur einzelne Objekte im Halbdunkel punktuell angestrahlt und geradezu auratisch inszeniert, oder wird der Raum gleichmäßig ausgeleuchtet? Die Debatte um diese Fragen erhielt durch den Bau der Kasseler Gemäldegalerie 1750 entscheidende Impulse.
Eine Frage des Blickwinkels : der Rechtsphilosoph Stefano Bertea forscht als Marie-Curie-Stipendiat
(2015)
Hauptrolle für die Krankenhaushygiene : »Tag der Patientensicherheit« am Universitätsklinikum
(2015)
Ernst, aber nicht hoffnungslos : Wissenschaftler berichten über Ergebnisse aus der Demenz-Forschung
(2015)
Empirical credit demand analysis undertaken at the aggregate level obscures potential behavioral heterogeneity between various borrowing sectors. Looking at disaggregated data and analyzing bank loans to non-financial companies, to financial companies, to households for consumption and for house purchases separately with respect to a common set of macroeconomic determinants may facilitate more accurate empirical relationships and more reliable insights for economic policy. Using quarterly Euro area panel data between 2003 and 2013, empirical evidence for heterogeneity in borrowing behavior across sectors and the credit cycle with respect to interest rates, output and house prices is found. The results motivate sector-specific, counter-cyclical capital requirements.
Bone marrow mononuclear cells (BMCs) are suitable for bone tissue engineering. Comparative data regarding the needs of BMC for the adhesion on biomaterials and biocompatibility to various biomaterials are lacking to a large extent. Therefore, we evaluated whether a surface coating would enhance BMC adhesion and analyze the biocompatibility of three different kinds of biomaterials. BMCs were purified from human bone marrow aspirate samples. Beta tricalcium phosphate (β-TCP, without coating or coated with fibronectin or human plasma), demineralized bone matrix (DBM), and bovine cancellous bone (BS) were assessed. Seeding efficacy on β-TCP was 95% regardless of the surface coating. BMC demonstrated a significantly increased initial adhesion on DBM and β-TCP compared to BS. On day 14, metabolic activity was significantly increased in BMC seeded on DBM in comparison to BMC seeded on BS. Likewise increased VEGF-synthesis was observed on day 2 in BMC seeded on DBM when compared to BMC seeded on BS. The seeding efficacy of BMC on uncoated biomaterials is generally high although there are differences between these biomaterials. Beta-TCP and DBM were similar and both superior to BS, suggesting either as suitable materials for spatial restriction of BMC used for regenerative medicine purposes in vivo.
In addition to the well-established quadrupole mixed-symmetry states, octupole and hexadecapole excitations with mixed-symmetry character have been recently proposed for the N = 52 isotones 92Zr and 94Mo. We performed two inelastic proton-scattering experiments to study this kind of excitations in the heaviest stable N = 52 isotone 96Ru. From the combined experimental data of both experiments absolute transition strengths were extracted.
Challenging voluntary CSR-initiatives – a case study on the effectiveness of the Equator Principles
(2015)
The Equator Principles (EPs) are a voluntary and self-regulatory Corporate Social Responsibility (CSR) initiative in the field of project finance. The EPs provide a number of principles to businesses to reduce the negative impacts of lending practices linked to environment-damaging projects. The paper argues that the actual impact of the EPs even now as revised version is still limited. This is due to their voluntary nature and their lack of adequate governance mechanisms, that is, enforcement, monitoring and sanctioning. With the help of RepRisk, which provides a database capturing third-party criticism as well as a company’s or project’s exposure to controversial socio-environmental issues, the paper evaluates the on-the-ground performances of the two ‘Equator banks’ Barclays and JPMorgan Chase and compares their performance with the one of the two non-Equator banks Deutsche Bank and UBS. The paper shows that the EPs do not have a substantial influence on the broader CSR-performance of multinational banks due to the EPs’ limited scope – focusing mainly on project finance – and the (still) existing various loopholes, grey areas and discretionary leeway. The paper also gives an overview of the main institutional shortcomings of the EPs and their association and discusses some potential reform steps which should be taken to further strengthen and ‘harden’ this ‘soft law’ EP-framework. The paper thus argues in favor of (more) mandatory and legally binding rules and standards at the transnational level to overcome the EPs’ ‘voluntariness bias’.
This paper is motivated by the fact that nearly half of U.S. college students drop out without earning a bachelor’s degree. Its objective is to quantify how much uncertainty college entrants face about their graduation outcomes. To do so, we develop a quantitative model of college choice. The innovation is to model in detail how students progress towards a college degree. The model is calibrated using transcript and financial data. We find that more than half of college entrants can predict whether they will graduate with at least 80% probability. As a result, stylized policies that insure students against the financial risks associated with uncertain graduation have little value for the majority of college entrants.
Global warming, changes in the hydrological cycle and enhanced marine primary productivity all have been invoked as having contributed to the occurrence of widespread ocean anoxia during the Cenomanian–Turonian oceanic anoxic event (OAE2; ~94 Ma), but disentangling these factors on a regional scale has remained problematic. In an attempt to separate these forcing factors, we generated palynological and organic geochemical records using a core spanning the OAE2 from Wunstorf, Lower Saxony Basin (LSB; northern Germany), which exhibits cyclic black shale–marl alternations related to the orbital precession cycle.
Despite the widely varying depositional conditions complicating the interpretation of the obtained records, TEX86H indicates that sea-surface temperature (SST) evolution in the LSB during OAE2 resembles that of previously studied sites throughout the proto-North Atlantic. Cooling during the so-called Plenus Cold Event interrupted black shale deposition during the early stages of OAE2. However, TEX86 does not vary significantly across black shale–marl alternations, suggesting that temperature variations did not force the formation of the cyclic black shale horizons. Relative (i.e., with respect to marine palynomorphs) and absolute abundances of pollen and spores are elevated during phases of black shale deposition, indicative of enhanced precipitation and run-off. High abundances of cysts from inferred heterotrophic and euryhaline dinoflagellates supports high run-off, which likely introduced additional nutrients to the epicontinental shelf resulting in elevated marine primary productivity.
We conclude that orbitally forced enhanced precipitation and run-off, in tandem with elevated marine primary productivity, were critical in cyclic black shale formation on the northern European epicontinental shelf and potentially for other OAE2 sections in the proto-Atlantic and Western Interior Seaway at similar latitudes as well.
The Time Projection Chamber (TPC), a large gaseous detector, is the main particle identification device of the ALICE experiment at the CERN LHC. The desired performance of the TPC defines the requirements for the gas mixture used in the detector. The active volume was filled with either Ne-CO2 (90-10) or Ne-CO2-N2 (90-10-5) during the first LHC running period. For LHC Run 2 the gas mixture is changed to Ar-CO2. Calculations of relevant gas properties are performed for Ar-based gas mixtures and compared to Ne-based gas mixtures to identify the most suitable Ar mixture. The drift velocity of ions in Ar is lower than in Ne. The closing time of the gating grid has to be adjusted accordingly to avoid drift field distortions due to back-drifting ions. The drift times of ions in the TPC readout chambers are calculated for the respective gas mixtures to determine the time to collect all ions from the amplification region. For LHC Run 3 the TPC readout chambers will be upgraded. The Multiwire Proportional Chambers (MWPCs) will be replaced by readout chambers based on Gas Electron Multipliers (GEMs) which are operated in continuous mode. As a consequence an ion backflow of the order of 1% causes significant space-charge distortions in the TPC drift volume. Similar distortions are expected in data taken specifically for the study of space-charge effects at the end of Run 1. The gating grid of the MWPCs is operated in the open state allowing the ions from the amplification region to enter the drift volume. The magnitude of the distortions in this data is measured and compared to the expectations for the TPC upgrade and results from current simulations.
Magnetoencephalography (MEG) measures neural activity non-invasively and at an excellent temporal resolution. Since its invention (Cohen, 1968, 1972), MEG has proven a most valuable tool in neurocognitive (Salmelin et al., 1994) and clinical research (Stufflebeam et al., 2009; Van ’t Ent et al., 2003). MEG is able to measure rapid changes in electrophysiological neural signals related to sensory and cognitive processes. The magnetic fields measured outside the head by MEG directly reflect the cortical currents generated by the synchronised activity of thousands of neuronal sources. This distinguishes MEG from functional magnetic resonance imaging (fMRI), where measurements are only indirectly related to electrophysiological activity through neurovascular coupling...
Signaling cooperation
(2015)
We examine what an applicant’s vita signals to potential employers about her willingness to cooperate in teams. Intensive social engagement may credibly reveal that an applicant cares about the well-being of others and therefore is less likely to free-ride in teamwork situations. We find that contributions in a public goods game strongly increase in a subject’s degree of social engagement as indicated on her résumé (and rated by an independent third party). Engagement in other domains, such as student or sports associations, is not positively correlated with contributions. In a prediction experiment with human resource managers from various industries, we find that managers use résumé content effectively to predict relative differences in subjects’ willingness to cooperate. Thus, young professionals signal important behavioral characteristics to potential employers through the choice of their extracurricular activities.
Knowledge about mass discrimination effects in a chemical ionization mass spectrometer (CIMS) is crucial for quantifying, e.g., the recently discovered extremely low volatile organic compounds (ELVOCs) and other compounds for which no calibration standard exists so far. Here, we present a simple way of estimating mass discrimination effects of a nitrate-based chemical ionization atmospheric pressure interface time-of-flight (CI-APi-TOF) mass spectrometer. Characterization of the mass discrimination is achieved by adding different perfluorinated acids to the mass spectrometer in amounts sufficient to deplete the primary ions significantly. The relative transmission efficiency can then be determined by comparing the decrease of signals from the primary ions and the increase of signals from the perfluorinated acids at higher masses. This method is in use already for PTR-MS; however, its application to a CI-APi-TOF brings additional difficulties, namely clustering and fragmentation of the measured compounds, which can be treated with statistical analysis of the measured data, leading to self-consistent results. We also compare this method to a transmission estimation obtained with a setup using an electrospray ion source, a high-resolution differential mobility analyzer and an electrometer, which estimates the transmission of the instrument without the CI source. Both methods give different transmission curves, indicating non-negligible mass discrimination effects of the CI source. The absolute transmission of the instrument without the CI source was estimated with the HR-DMA method to plateau between the m∕z range of 127 and 568 Th at around 1.5 %; however, for the CI source included, the depletion method showed a steady increase in relative transmission efficiency from the m∕z range of the primary ion (mainly at 62 Th) to around 550 Th by a factor of around 5. The main advantages of the depletion method are that the instrument is used in the same operation mode as during standard measurements and no knowledge of the absolute amount of the measured substance is necessary, which results in a simple setup.
Teil XIV unserer Serie zum „Islamischen Staat“. Der „Islamische Staat“ veröffentlicht unter dem Namen „Dabiq“ eine eigene Propagandazeitschrift. Die mit zahlreichen großformatigen Fotos hergestellte Publikation mutet dabei wie ein modernes Magazin an und ist optisch durchaus mit dem seit mehreren Jahren bekannten Magazin „Inspire“ der al-Qaida vergleichbar. Im Folgenden soll die deutsche Ausgabe in die Rekrutierungs- und Medienstrategie des IS eingeordnet und mögliche Folgerungen für die Sicherheitslage und die Tätigkeit der deutschen Sicherheitsbehörden vorgenommen werden.
Der Innensenator der Freien Hansestadt Bremen, Ulrich Mäurer, hat die Forderung nach einer Nationalen Präventionsstrategie gegen gewaltbereiten Extremismus erhoben. Ziel dieser Initiative ist es, durch eine effektive Verknüpfung aller beteiligten staatlichen Akteure in diesem Feld eine größtmögliche Wirkung von Präventions- und Deradikalisierungsmaßnahmen zu erreichen. Sein Vorstoß wird einer der zentralen, sicherlich aber auch der kontroversen Beratungspunkte der nächsten Sitzung der Ständigen Konferenz der Innenminister und -senatoren der Länder (Innenministerkonferenz – IMK) Ende Juni sein...
Deutschland steht angesichts der seit rund sechs Wochen massiv angestiegenen Zahlen von Flüchtlingen insbesondere aus Krisengebieten des Nahen und Mittleren Ostens vor einer der größten gesellschaftlichen Herausforderungen der Nachkriegsgeschichte. Je nach Quelle werden alleine in diesem Jahr rund 800.000 Flüchtlinge (die derzeitige Prognose des Bundesamtes für Migration und Flüchtlinge), bis zu einer Million (Bundesminister Sigmar Gabriel) oder auch 1,5 Millionen Zuwanderer erwartet. Ein sehr großer Anteil dieser Menschen wird vermutlich als asylberechtigt anerkannt werden. Und da ein weit überproportional hoher Anteil dieser Flüchtlinge alleinreisend war, ist damit zu rechnen, dass im Laufe der nächsten Jahre eine mutmaßlich noch größere Anzahl von Familienangehörigen nachziehen wird. Deutschland muss sich also perspektivisch auf mehrere Millionen neue Einwohner einstellen...
Durch das entschlossene und überaus mutige Eingreifen mehrerer Passagiere konnte am 21. August 2015 an Bord des Thalys-Schnellzuges von Amsterdam nach Paris ein mutmaßlich jihadistisch motivierter Attentäter daran gehindert werden, zahlreiche Menschen zu ermorden. Wäre der Täter nicht gehindert worden, hätte er, bewaffnet mit einem Sturmgewehr, einer Pistole und einem Messer, dutzende Opfer finden können...