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Do Businessmen Make Good Governors?
No full textThis paper empirically evaluates the economic performance of U.S. state governors who came to the position from a business background (CEO governors), focusing on the growth rate of real personal income per capita, unemployment rate, and income inequality. Methodologically, we apply a matching method to account for the endogeneity of political selection. Using entropy balancing, we identify credible counterfactuals for CEO governors, that is, governors without a business background who took office under similar economic and fiscal situations. We find, first, that businesspeople tend to take office in times of economic and fiscal strain. Second, the tenures of CEO governors are associated with a 0.6 percentage points higher annual income growth rate and a 0.6 percentage points lower unemployment rate than are the tenures of non-CEO governors. Also, state-level income inequality decreases when CEO governors hold office, indicating that low-income households benefit from the economic upswing. Third, the positive effect of having a CEO governor increases with time in office. Fourth, Republican CEO governors perform slightly better than their Democratic colleagues
In vitro study of the marginal gap on class II and class V composite fillings after artificial ageing
No full textEines der wichtigsten Kriterien zur Beurteilung von Kompositrestaurationen ist der Randschluss. Neben Materialeigenschaften und technischer Anwendung hat die Kavitätenpräparation Einfluss auf die Ausbildung eines Randspaltes und folglich auf die Langlebigkeit einer Kompositfüllung.
Die vorliegende Studie sollte den Einfluss verschiedener Kavitätenpräparationen und artifizieller Alterung auf die Randqualität von Klasse-II- und Klasse-V-Kavitäten untersuchen.One of the most important criteria to evaluate composite restorations is the marginal fit. Besides material properties and technical application, the cavity preparation has an influence on the formation of a marginal gap and thus on the longevity of a composite filling.
The aim of this study was to evaluate the influence of different cavity preparations and artificial ageing on the quality of the marginal fit of class II and class V cavities
Management of Paediatric Cardiac Arrest due to Shockable Rhythm : A Simulation-Based Study at Children’s Hospitals in a German Federal State
No full text(1) Background: To improve the quality of emergency care for children, the Hessian Ministry
for Social Affairs and Integration offered paediatric simulation-based training (SBT) for all children’s
hospitals in Hesse. We investigated the quality of paediatric life support (PLS) in simulated paediatric
resuscitations before and after SBT. (2) Methods: In 2017, a standardised, high-fidelity, two-day
in-house SBT was conducted in 11 children’s hospitals. Before and after SBT, interprofessional
teams participated in two study scenarios (PRE and POST) that followed the same clinical course
of apnoea and cardiac arrest with a shockable rhythm. The quality of PLS was assessed using a
performance evaluation checklist. (3) Results: 179 nurses and physicians participated, forming
47 PRE and 46 POST interprofessional teams. Ventilation was always initiated. Before SBT, chest
compressions (CC) were initiated by 87%, and defibrillation by 60% of teams. After SBT, all teams
initiated CC (p = 0.012), and 80% defibrillated the patient (p = 0.028). The time to initiate CC decreased
significantly (PRE 123 ± 11 s, POST 76 ± 85 s, p = 0.030). (4) Conclusions: The quality of PLS in
simulated paediatric cardiac arrests with shockable rhythm was poor in Hessian children’s hospitals
and improved significantly after SBT. To improve children’s outcomes, SBT should be mandatory for
paediatric staff and concentrate on the management of shockable rhythms.Gefördert durch den Open-Access-Publikationsfonds der UB Marburg
Changing attitudes towards psychotherapy via social observations: are similarities more important than discrepancies?
No full textObjectives: Therapy expectations and attitudes towards psychotherapy contribute substantially to the outcome,
process and duration of psychotherapy. The a priori use of role model videos seems to be promising for changing
expectations and attitudes towards psychotherapy. In contrast, underlying mechanisms, like identifying with the
role model, have been sparsely investigated in studies so far. For instance, the effects of similarities and differences
between the role model and the observer are not clear yet.
Methods: A total of 158 persons were recruited and randomly assigned to four groups. In one of three experimental
groups, participants watched an expectation-optimised video with patients giving information about their mostly
positive therapy outcomes (positive model). Two further experimental groups saw the same video, but either received
instructions to focus on similarities (similarity group) or on differences (discrepancy group) between the patients and
themselves. A further control group watched a video with patients who gave information about their symptoms. As
the primary outcome variable, we assessed attitudes towards psychotherapy using the Questionnaire on Attitudes
towards Psychotherapy (QAPT). It was filled in before and after watching the video and after a two-week follow-up
period.
Results: Contrary to the hypotheses, the discrepancy group and the experimental group without further
intervention (positive model) showed significant improvements in their attitudes towards psychotherapy after
watching the video, while such an effect was not found in the similarity group or control group.
Conclusion: Focusing on similarities between patient examples and the observer does not support a change in
therapy expectations or attitudes through observation, while a positive video model without instructions, or with the
instruction to focus on differences does. Attentional interference and depth of cognitive evaluation are discussed as
possible reasons.
Trial registration: Ethical approval (2018-19k) was obtained from the ethics committee of the Psychological
Department, University of Marburg, and the trial was registered at Aspredicted.org (#22,205; 16.04.2019).Gefördert durch den Open-Access-Publikationsfonds der UB Marburg
Ist BNE im Geographieunterricht zukunftsweisend? Plädoyer für eine adaptionsorientierte Klimabildung
No full textDie globale Erwärmung hat bereits beim jetzigen Stand massive Auswirkungen auf die Zukunftsperspektiven junger Menschen.
Die Begrenzung der Erwärmung auf den abschätzbaren Rahmen von 1,5 °C erfordert sofortiges, entschlossenes und
globales Handeln. Vor dem Hintergrund der fortschreitenden Entwicklung wird immer deutlicher, dass eine ausreichende
Eindämmung der globalen Erwärmung wenig wahrscheinlich ist und der Beitrag durch Bildung im schulischen Kontext
geringe Effekte leisten wird. Umso wichtiger erscheint es, den Fokus auf eine schüler*innenorientierte Bildung zu setzen.
Im Zentrum dieser Überlegungen steht die Frage: Welche Bildungsangebote brauchen junge Menschen, um eine herausfordernde
Zukunft erfolgreich gestalten zu können? Im Hinblick auf die alarmierenden Ergebnisse aus Studien über Ängste
angesichts des Klimawandels beleuchtet dieser Artikel zunächst, wie die Resilienz von Schüler*innen gestärkt werden kann.
Anschließend wird das Potenzial der geographischen Bildung für eine zukunftsorientierte Auseinandersetzung mit der globalen
Erwärmung diskutiert, die einen konstruktiven Umgang mit den Herausforderungen fördern kann.Global warming is already massively impacting the future prospects of young people. Limiting global warming to an estimated
1.5 °C requires immediate, decisive and global action. Against the backdrop of ongoing development, it is becoming
increasingly clear that sufficient containment of global warming is unlikely and that the contribution made by education in
the school context will have little effect. This makes it even more important to focus on student-oriented education. At the
heart of these considerations is the question: What educational opportunities do young people need in order to successfully
shape a challenging future? In view of the alarming findings from studies on fears in the face of climate change, this article
first examines how the resilience of pupils can be strengthened. It then discusses the potential of geographical education for
a future-oriented approach to global warming, which can promote a constructive way of dealing with the challenges.Gefördert durch den Open-Access-Publikationsfonds der UB Marburg
The Rho GEF Trio is transported by microtubule plus-ends and involved in focal adhesion formation in migrating neural crest cells
No full textDirected cell migration depends on cytoskeletal rearrangements, protrusion formation, cell
contraction and focal adhesion turnover. These processes are regulated by spatiotemporal
fine-tuning of Rho GTPase activity. The Rho guanine nucleotide exchange factor (GEF) Trio
is well suited to control Rho GTPase activity by merging two catalytic GEF domains, allowing
control over Rac1 and RhoA within a single protein. However, strict spatiotemporal control of
the activity of the Trio GEF domains at the cellular level is necessary. We recently
demonstrated that Trio is required for Xenopus neural crest (NC) cell protrusion formation and
migration. Here, we examine the dynamic localization of Trio and its impact on Trio's role in
NC cell migration. Live-cell imaging revealed that the Trio GEF2 domain co-localizes with EB3
at microtubule plus-ends. Microtubule trafficking of Trio appears to be important for its function,
as a mutant GEF2 construct lacking the SxIP amino acid motif responsible for microtubule
plus-end binding, was unable to rescue the Trio loss-of-function induced NC migration defects
in vivo and in vitro. In addition, our analysis of microtubule dynamics in migrating neural crest
cells revealed that Trio knockdown results in the stabilization of microtubules at cell-cell
contacts, while destabilizing them at the leading edge compared to the control. Furthermore,
our findings indicate that Trio is involved in focal adhesion dynamics, as analyzed by live-cell
imaging of focal adhesion assembly and disassembly. Our data suggest that Trio is transported
by microtubules to specific subcellular locations, where it has distinct functions in controlling
microtubule stability, protrusion formation and adhesive functions during directed NC cell
migration. Furthermore, TRIO gene mutations have been shown to cause neurodevelopmental
disorders and facial dysmorphisms in patients, possibly by inhibiting the migration of neural
crest cells. Similar clinical features were observed in individuals with mutations in the MAPRE2
and TUBB genes. We successfully induced Mapre2 and Tubb loss-of-function in Xenopus
embryos by injecting specific translation-blocking morpholinos and demonstrate, comparable
to patient data, that this knockdown results in NC migration defects and craniofacial
malformations. These experiments will serve as a starting point to analyze whether Trio,
Mapre2 and Tubb operate within the same signaling pathways to regulate microtubule
dynamics, focal adhesion turnover and, thereby, cell motility.Die gerichtete Zellmigration hängt von einem dynamischen Zytoskelett, der Bildung von
Zellfortsätzen, der Zellkontraktion und dynamischen fokalen Adhäsionen ab. Diese Prozesse
werden durch ein räumliches und zeitliches Feintuning der Aktivität von Rho-GTPasen
reguliert. Der Rho-Guanin-Nukleotid-Austauschfaktor (GEF) Trio ist ein ausgezeichneter
Kandidat, um die Aktivität von Rho-GTPasen zu kontrollieren, da er zwei katalytische GEFDomänen
vereint und so die Kontrolle über Rac1 und RhoA in einem einzigen Protein
ermöglicht. Allerdings ist eine strikte räumliche und zeitliche Regulation der Aktivität der Trio-
GEF-Domänen auf zellulärer Ebene erforderlich. Wir konnten bereits zeigen, dass Trio für die
Bildung von Zellfortsätzen sowie für die gerichtete Zellmigration in Xenopus-
Neuralleistenzellen notwendig ist. In dieser Studie untersuchen wir die dynamische
Lokalisation von Trio und deren Einfluss auf seine Funktion bei der Neuralleistenzellmigration.
Die Lebendzellanalyse zeigte, dass die Trio-GEF2-Domäne mit EB3 an Miktotubuli-Plus-
Enden kolokalisiert. Der Transport von Trio durch Mikrotubuli scheint für seine Funktion wichtig
zu sein, denn ein mutiertes GEF2-Konstrukt, dem das Aminosäuremotiv SxIP fehlte, welches
für die Bindung an Mikrotubuli-Plus-Enden verantwortlich ist, konnte den Trio-Verlust in
Neuralleistenzellen in vivo und in vitro nicht ausgleichen, während das Wildtyp-GEF2-
Konstrukt dazu in der Lage war. Darüber hinaus zeigte unsere Analyse der Mikrotubuli-
Dynamik in migrierenden Neuralleistenzellen, dass der Trio-Knockdown zu einer Stabilisierung
der Mikrotubuli an Zell-Zell-Kontakten führt, während sie an der Zellfront im Vergleich zur
Kontrolle destabilisiert werden. Gleichzeitig deuten unsere Ergebnisse darauf hin, dass Trio
an der Dynamik der fokalen Adhäsionen beteiligt ist. Zusammenfassend zeigen wir hier, dass
Trio über Mikrotubuli an spezifische subzelluläre Orte transportiert werden kann, wo es
verschiedene Funktionen bei der Kontrolle der Mikrotubuli-Stabilität, der Ausbildung von
Zellfortsätzen und der Zelladhäsion während der gerichteten Migration von Neuralleistenzellen
ausübt. Weiterhin wurde bereits gezeigt, dass TRIO-Genmutationen zu neurologischen
Entwicklungsstörungen und Gesichtsdysmorphien bei Patienten führen, möglicherweise durch
eine beeinträchtigte Neuralleistenzellmigration. Ähnliche klinische Merkmale wurden bei
Personen mit Mutationen in den Genen MAPRE2 und TUBB beobachtet. Wir konnten den
Funktionsverlust von Mapre2 und Tubb in Xenopus Embryonen durch Injektion spezifischer
translationsblockierender Morpholino Oligonukleotide nachahmen und zeigen, dass dieser in
Xenopus, ähnlich wie in Patienten, zu Defekten in der Neuralleistenzellmigration und zu
kraniofazialen Fehlbildungen führt. Diese Experimente dienen als Ausgangspunkt, um zu
analysieren, ob Trio, Mapre2 und Tubb innerhalb der gleichen Signalkaskaden agieren, um
die Mikrotubuli-Dynamik, die fokale Adhäsion und damit die Zellmotilität zu regulieren
Development and implementation of a treatment pathway to reduce coronary angiograms - lessons from a failure
No full textBackground
The rates of coronary angiograms (CA) and related procedures (percutaneous intervention [PCI]) are significantly higher in Germany than in other Organisation for Economic Co-ordination and Development (OECD) countries. The current guidelines recommend non-invasive diagnosis of coronary heart disease (CHD); CA should only have a limited role in choosing the appropriate revascularisation procedure. The aim of the present study was to explore whether improvements in guideline adherence can be achieved through the implementation of regional treatment pathways. We chose four regions of Germany with high utilisation of CAs for the study. Here we report the results of the concomitant qualitative study.
Methods
General practitioners and specialist physicians (cardiologists, hospital-based cardiologists, emergency physicians, radiologists and nuclear medicine specialists) caring for patients with suspected CHD were invited to develop regional treatment pathways. Four academic departments provided support for moderation, provision of materials, etc. The study team observed session discussions and took notes. After the development of the treatment pathways, 45 semi-structured interviews were conducted with the participating physicians. Interviews and field notes were transcribed verbatim and underwent qualitative content analysis.
Results
Pathway development received little support among the participants. Although consensus documents were produced, the results were unlikely to improve practice. The participants expressed very little commitment to change. Although this attempt clearly failed in all study regions, our experience provides relevant insights into the process of evidence appraisal and implementation. A lack of organisational skills, ignorance of current evidence and guidelines, and a lack of feedback regarding one’s own clinical behaviour proved to be insurmountable. CA was still seen as the diagnostic gold standard by most interviewees.
Conclusions
Oversupply and overutilisation can be assumed to be present in study regions but are not immediately perceived by clinicians. The problem is unlikely to be solved by regional collaborative initiatives; optimised resource planning within the health care system combined with appropriate economic incentives might best address these issues.Gefördert durch den Open-Access-Publikationsfonds der UB Marburg
International Marriage for Homogeneity? - Evidence from Marriage Migration in South Korea
No full textThis paper investigates empirically whether cultural, racial, and linguistic
similarities increase marriage migration. By using marriage migration data from South Korea, I find that the similarities between an origin country and South Korea pull more marriage migration, but the positive effects of the similarities are mainly driven by female marriage migrants from middle and low income countries. The pulling effects of the similarities can be explained by female deficits in the marital age group in South Korea that motivate Korean men to seek foreign brides who share similar traits with locals
Regulation of dynamic front-rear cell polarity by the Frz chemosensory system in Myxococcus xanthus
No full textBacterial cells are spatiotemporally highly organized, with proteins localizing to distinct subcellular regions. The rod-shaped Myxococcus xanthus cells move across surfaces with defined front-rear polarity. This polarity is determined by the small Ras-like GTPase MglA that localizes to the leading cell pole in its GTP-bound form. The nucleotide-bound form of MglA and its localization are regulated by the remaining five proteins of the polarity module. All six
proteins of the polarity module localize asymmetrically to the cell poles. Occasionally, cells invert polarity and, in parallel, reverse their direction of movement. The Frz chemosensory system triggers the inversion of cell polarity and, therefore, cellular reversals. The two output response regulators of the Frz system, FrzX and FrzZ, localize to the lagging and leading cell poles, respectively, in their phosphorylated form, targeting the proteins of the polarity module and, thereby jointly causing an inversion of the polarity of these proteins. However, the molecular mechanism that bridges FrzX and FrzZ and the proteins of the polarity module are poorly understood.
Here, we addressed this question, focusing on FrzZ. Using a biotin-based proximity labeling approach, we identify PixA as a strong candidate for directly interacting with phosphorylated FrzZ. Epistasis analyses support that FrzZ and PixA regulate reversals in the same output branch of the Frz system, and PixA inhibits reversals. In this branch, FrzZ~P induces reversals by inhibiting PixA, thereby relieving the PixA-mediated inhibition of reversals. PixA localized weakly at the lagging pole between reversals. Strikingly, Frz signaling altered PixA localization to the pole. Genetic analyses suggest that FrzZ inhibits lagging pole localization of PixA.
During Frz signaling, FrzZ~P “pulls” PixA to the leading pole, while FrzX~P “pushes off” PixA at the lagging pole. Elevated levels of PixA resulted in increased lagging pole localization of PixA and strong reduction of reversals. Altogether, our findings support a model in which PixA
inhibits reversals at the lagging cell pole while FrzX~P and FrzZ~P, in a “push and pull” mechanism, relocate PixA from the lagging to the leading pole, thereby allowing a reversal to occur.
In proximity labelling approaches, we identified the response regulator PglH as a potential interaction partner of PixA, FrzX, and MglA. A ΔpglH mutant had a hyperreversing phenotype, suggesting that PglH is a strong candidate for also being involved in regulating leading-lagging cell polarity in M. xanthus.Bakterienzellen sind räumlich und zeitlich hoch organisiert. Dabei lokalisieren Proteine in bestimmten subzellulären Regionen. Das stäbchenförmige Bakterium Myxococcus xanthus bewegt sich auf Oberflächen mit definierter Vorder-Rück-Polarität. Diese Polarität wird durch die Ras-ähnliche GTPase MglA bestimmt, welche in ihrer GTP-gebundenen Form zum vorderen Zellpol lokalisiert. Die Nukleotid-gebundene Form von MglA und deren Lokalisation werden von insgesamt fünf weiteren Proteinen des Polaritätsmoduls reguliert. Diese insgesamt sechs Proteine lokalisieren asymmetrisch an den Zellpolen. Gelegentlich invertieren Zellen ihre Polarität, um ihre Bewegungsrichtung zu ändern. Diese Umpolung der Zellpolarität wird durch das Frz-Chemosensory-System ausgelöst. Die beiden Output- Regulatoren FrzX und FrzZ lokalisieren, wenn sie phosphoryliert sind, an dem hinteren oder vorderen Zellpol, wo sie die Proteine des Polaritätsmoduls anvisieren, um deren Polariät zu invertieren. Allerdings sind die molekularen Mechanismen, die FrzX und FrzZ mit den Proteinen des Polaritätsmoduls verknüpfen, immer noch unzureichend verstanden. In der vorliegenden Studie wird diese Fragestellung mit einem Fokus auf FrzZ untersucht.
Mit Hilfe einer biotinbasierten Proximity-Labelling Methode, konnten wir PixA als einen vielversprechenden Kandidaten für eine direkte Interaktion mit phosphoryliertem FrzZ identifizieren. Epistase-Experimente unterstützen die Hypothese, dass FrzZ und PixA im selben Pfad des Frz Systems agieren, um Zellumkehrungen zu regulieren, wobei PixA diese hemmt. In diesem Pfad induziert FrzZ~P Zellumkehrungen, indem es PixA hemmt und dadurch die von PixA vermittelte Hemmung von Zellumkehrungen aufhebt. In Zellen, die sich in eine Richtung fortbewegen, lokalisiert PixA instabil am hinteren Zellpol. Bemerkenswerterweise ändern Signale des Frz-Systems diese Lokalisation. Genetische Analysen untermauern, dass FrzZ PixA Lokalisation am hinteren Pol hemmt. Während der Frz Signalweiterleitung „zieht“ FrzZ~P PixA zum vorderen Pol. Gleichzeitig „schiebt“ FrzZ~P PixA weg vom hinteren Pol. Erhöhte Mengen von PixA führen zu vermehrter Lokalisation von PixA am hinteren Zellpol und einer starken Reduzierung von Zellumkehrungen. Insgesamt unterstützen unsere Ergebnisse ein Modell, bei dem PixA Zellumkehrungen am hinteren Zellpol hemmt, während FrzZ~P und FrzX~P in einem „Push and Pull“ Mechanismus PixA vom hinteren zum vorderen Zellpol relokalisieren und so Zellumkehrungen ermöglichen.
In Proximity-Labelling Experimenten, konnte der Response Regulator PglH als potenzieller Interaktionspartner von PixA, FrzX und MglA identifiziert werden. Eine ΔpglH Mutante, zeigte einen hyper-zellumkehrenden Phänotyp. Dies weist darauf hin, dass PglH ein vielversprechender Kandidat ist, welcher ebenfalls an der Regulation der Vorder-Rück- Polarität in M. xanthus beteiligt sein könnte
Länderrisiko: Die ökonomischen Konsequenzen einer Herabstufung durch die Rating-Agenturen
No full textBei der Kritik an den Rating-Agenturen wird häufig missachtet, dass ihre Macht weitgehend politikgemacht ist. Es sind der Staat und die EZB, die über Gesetze und Regulierungen den Ratings eine Multiplikatorwirkung zuschreiben. Dieser Beitrag skizziert anhand der Länder-ratings die einschlägigen Wirkungskanäle