Mechanistic insights to the effective pathways of global and local climate change in a Baltic Sea seaweed - epiphyte - mesograzer system = Mechanistische Einblicke in die Wirkungspfade von globalen und lokalen Faktoren des Klimawandels auf ein Seetang - Epiphyten - Weidegänger System der Ostsee

Anthropogenic greenhouse gas emissions have been driving global climate change and they will continue to do so over the course of the 21st century. Most of the marine biosphere and especially coastal marine systems have suffered from high anthropogenic pressure per se and it is possible that the novel burden of very rapidly proceeding global climate change triggers shifts to alternative regimes and functioning in marine ecosystems. In the light of this background, my dissertation aims to contribute to the mechanistic understanding of global and local climate change effects on a common coastal marine seaweed (Fucus vesiculosus, Phaeophyceae) system of the Baltic Sea. The results of my experimental studies provide important mechanistic clues about the underlying direct and indirect effective pathways of environmental change in the studied seaweed system. To the best of my knowledge, it is one of the first studies which assess the seasonal variability of the same environmental factors on the same marine system over the course of one year. The detected context-dependency of global climate change effects within one ecosystem clearly shows that our understanding of the basic underlying ecosystem processes and patterns forms a prerequisite for testing, predicting and managing future ecological change in marine systems. Given that grazing forms a crucial ecological force in many coastal vegetated systems, the identified underlying mechanisms of change (top-down and bottom-up control) may allow reference to other similarly structured coastal systems. Importantly my findings point out, that ecological impacts of global climate change may be underestimated if local perturbation is disregarded and, thus, underline the chance and responsibility of local ecosystem management

Mechanistische Einblicke in die Wirkungspfade von globalen und lokalen Faktoren des Klimawandels auf ein Seetang - Epiphyten - Weidegänger System der Ostsee

Anthropogenic greenhouse gas emissions have been driving global climate change and they will continue to do so over the course of the 21st century. Most of the marine biosphere and especially coastal marine systems have suffered from high anthropogenic pressure per se and it is possible that the novel burden of very rapidly proceeding global climate change triggers shifts to alternative regimes and functioning in marine ecosystems. In the light of this background, my dissertation aims to contribute to the mechanistic understanding of global and local climate change effects on a common coastal marine seaweed (Fucus vesiculosus, Phaeophyceae) system of the Baltic Sea. The results of my experimental studies provide important mechanistic clues about the underlying direct and indirect effective pathways of environmental change in the studied seaweed system. To the best of my knowledge, it is one of the first studies which assess the seasonal variability of the same environmental factors on the same marine system over the course of one year. The detected context-dependency of global climate change effects within one ecosystem clearly shows that our understanding of the basic underlying ecosystem processes and patterns forms a prerequisite for testing, predicting and managing future ecological change in marine systems. Given that grazing forms a crucial ecological force in many coastal vegetated systems, the identified underlying mechanisms of change (top-down and bottom-up control) may allow reference to other similarly structured coastal systems. Importantly my findings point out, that ecological impacts of global climate change may be underestimated if local perturbation is disregarded and, thus, underline the chance and responsibility of local ecosystem management.Anthropogene Treibhausgasemissionen haben zu globalen Klimaveränderungen auf der Erde geführt und werden den Klimawandel im Verlauf des 21. Jahrhunderts vorantreiben. Da insbesondere küstennahe marine Ökosysteme bereits stark durch menschliche Eingriffe beeinträchtig sind, ist es möglich, dass die zusätzlichen schnellen und starken Veränderungen im marinen Lebensraum zu Ökosystemwechseln (Regime-shifts) oder veränderten Ökosystemfunktionen führen. Vor diesem Hintergrund strebt meine Dissertation an zum mechanistischen Verständnis von Effekten des Klimawandels auf ein weitverbreitetes küstennahes Seetang System (Fucus vesiculosus, Phaeophyceae) der Ostsee beizutragen. Die Ergebnisse meiner experimentellen Studien bieten wichtige mechanistische Informationen über die direkten und indirekten Wirkungspfade von Umweltveränderung im untersuchten Seetang System. Nach meinem Kenntnisstand ist dies eine der ersten Studien, die die saisonale Variabilität des gleichen Umweltfaktors am gleichen System in vier aufeinanderfolgenden Jahreszeiten untersucht. Die hohe Kontextgebundenheit der Effekte im experimentellen System zeigt, dass ein Verständnis der grundlegenden Ökosystemprozesse und jahreszeitlichen Muster eine Voraussetzung für das Testen, Vorhersagen und Management von ökologischen Veränderungen in marinen Systemen ist. Da der Weidedruck durch Mesoherbivore eine essentielle strukturierende Kraft in vielen küstennahen Makroalgen und Seegras Systemen darstellt, erlaubt die hier gewonnene Erkenntnis über sich durch Erwärmung verändernde Mechanismen (Top-down und Bottom-up Kontrolle) möglicherweise Bezugnahme auf andere ähnlich strukturierte küstennahe Systeme. Wesentlich ist die Erkenntnis, dass ökologische Auswirkungen des globalen Klimawandels unterschätzt werden könnten, wenn bestehende lokale Belastungen von Ökosystemen nicht berücksichtigt werden. Dieses Ergebnis unterstreicht die Chance und Verantwortung von lokalem Ökosystemmanagement

An experimental analysis of bounded rationality: Applying insights from behavioral economics to information systems

The paradigm of bounded rationality considers the limited ability of individuals to make consistent and rational choices. Due to the scarcity of research on this phenomenon in information systems, we conducted an experimental study investigating decision-making regarding risk preferences and social preferences. Moreover, we explored the stability of these preferences under different conditions and uncovered the role of information retrieval in individual decision-making. We find that although individuals are generally risk-averse and egoistic, none of these preferences is stable under the conditions tested which provides indices of boundedly rational decision-making. Although the information retrieved by participants generally allows to infer their preferences, the increasing amount and complexity of this information again often results in boundedly rational behavior.bounded rationality, experimental design, information retrieval, stability of attitudes and behavior, cognitive tracing, behavioral economics, behavioral information systems

Innate immunity, oxidative stress and body indices of Eurasian perch Perca fluviatilis after two weeks of exposure to artificial light at night

Artificial light at night (ALAN) can disrupt biological rhythms of fish and other vertebrates by changing the light information of the nocturnal environment. Disrupted biorhythms can impair the immune system of vertebrates as it has been shown for conditions with continuous illumination or long-day photoperiod in many vertebrates, including fish. Nonetheless, this has not been shown so far for typical ALAN scenarios with high light intensities during day and low light intensities at night. Therefore, in this study, proxies for the innate immune system and oxidative stress as well as body indices of Eurasian perch Perca fluviatilis were measured under a wide range of intensities of nocturnal illumination. The authors found no changes in parameters of the innate immune system and no significant changes in proxies for oxidative stress after 2-week exposures to nocturnal illuminance ranging from 0.01 lx to 1 lx in one experiment or from 1 lx to 100 lx in a second experiment. A decrease in the hepato-somatic index at the highest tested light intensity of 100 lx compared to the dark control was the only significant difference in all parameters among treatments. After 2 weeks of exposure, ALAN does not seem to seriously challenge the innate immune system and seems to cause less oxidative stress than expected. The results of this study contradict the findings from other studies applying continuous illumination or long-day photoperiod and highlight the importance of further research in this field. Because ALAN represents a sustained modulation of the environment that may have cumulative effects over time, long-term studies are required for a better understanding of how ALAN modulates the health of fish.Leibniz Association http://dx.doi.org/10.13039/501100001664Peer Reviewe

Vom Schrumpfen zur Integration? Thüringens Willkommenskultur und die sozialräumliche Integration von Flüchtlingen in Gera

Das Paradigma der schrumpfenden Stadt hat in Thüringen wie in allen ostdeutschen Bundesländern die Vorstellung von der Entwicklung der Stadt geprägt und dazu geführt, dass der demographische Wandel als entscheidender Faktor angesehen wird. Konsequenterweise ist dieser Prozess von zum Teil stark rückgebauten Infrastruktur- und Versorgungseinrichtungen geprägt.Seit der Regierungsübernahme durch die rot-rot-grüne Koalition im Jahr 2014 wird durch die Propagierung einer »Willkommenskultur« als einer auf Integration setzenden Migrationspolitik ein anderes, leitendes Narrativ eingeführt. Die Flüchtlingsaufnahme wird dabei als Chance für die lokale Entwicklung verstanden, beispielsweise als Kompensation eines weiteren Schrumpfungsprozesses und wachsenden Fachkräftemangels. Dies trifft in den Kommunen jedoch auf ein geteiltes Echo, sodass sich intensive Diskussionen über die Aufnahme und den Umgang mit Geflüchteten vor Ort finden lassen.In dem vorgeschlagenen Beitrag stellen die Autorinnen der Bauhaus-Universität Weimar ihre Forschungen aus dem Projekt »Willkommensstädte« sowie dem Projekt »Migration statt Schrumpfung« vor. Dabei wird anhand des Fallbeispiels der Stadt Gera aufgezeigt, inwieweit und in welcher Ausgestaltung sich einerseits Formen sozial-räumlicher Integration entwickeln und andererseits, was dieser jedoch in dem von Schrumpfung geprägten ostdeutschen Kontext entgegensteht.Gera als drittgrößte Stadt Thüringens ist dabei zwar keine Ausnahme und hatte bis vor wenigen Jahren kaum Erfahrungen mit (internationaler) Migration. Vor diesem Hintergrund werden die Möglichkeiten und Herausforderungen im Alltag von Geflüchteten dargestellt und somit Ansätze eines neuen Integrationsprozesses aufgezeigt. Dies umfasst die Betrachtung der darin beteiligten zivilgesellschaftlichen wie formal-administrativen Ebenen und Akteure. Nicht zuletzt wird die Beziehung zwischen Landes- und kommunaler Ebene in Bezug auf diesen Paradigmenwechsel beleuchtet.Der Beitrag beruht auf Interviews mit Geflüchteten sowie ehren- und hauptamtlichen Menschen aus den Bereichen der Versorgung und Integration. Durch teilnehmende Beobachtungen in verschiedenen Alltagsorten der Geflüchteten wird zudem ein Einblick in die Problemfelder aber auch Spielräume innerhalb Geras in Bezug auf die sozialräumliche Integration von Geflüchteten gegeben

Warming has stronger direct than indirect effects on benthic microalgae in a seaweed system in spring

Using outdoor mesocosms we investigated the relative importance of the direct and indirect (here: altered grazing) effects of seawater warming on benthic microalgae in a Baltic Sea Fucus vesiculosus (Phaeophyceae) system during the spring season. Seawater warming had a positive main effect on microalgal total biomass accrual and growth rate and on total mesograzer abundance and biomass. Moreover, under the existing resource-replete conditions in spring the direct positive effect of warming on microalgae was stronger than its indirect negative effect through enhanced grazing. The outcome of this study contrasts previous observations from the summer and winter season, where indirect effects of warming mediated by altered grazing were identified as an important driver of primary biomass in the Fucus system. In this context, the results from the spring season add mechanistic information to the overall understanding of the seasonal variability of climate change effects. They suggest that the relative importance of the underlying direct and indirect effective pathways of warming and the overall effect on the balance between production and consumption are influenced by the trophic state of the system, which in temperate regions is related to season

Quality of life of nursing home residents with dementia: Validation of the German version of the ICECAP-O

Objectives: To validate the ICECAP-O capability wellbeing measure's German translation in older people with dementia living in a nursing home, and to investigate the influence of proxy characteristics on responses. Method: Cross-sectional study. For 95 residents living in a German nursing home, questionnaires were completed by nursing professionals serving as proxy respondents. We investigated the convergent validity of the ICECAP-O with other Quality of Life (Qol) measures, the EQ-5D extended with a cognitive dimension (EQ-5D+C), the Alzheimer's Disease Related Quality of Life (ADRQL) measures, and the Barthel-index measure of Activities of Daily Living (ADL). Discriminant validity was investigated using bivaria

The role of radiative cooling and leaf wetting in air–leaf water exchange during dew and radiation fog events in a temperate grassland

During prolonged dry periods, non-rainfall water (NRW) plays a vital role as water input into temperate grasslands, affecting the leaf surface water balance and plant water status. Previous chamber and laboratory experiments investigated air–leaf water exchange during dew deposition, but overlooked the importance of radiative cooling on air–leaf water exchange because the chamber is a heat trap, preventing radiative cooling. To complement these previous studies, we conducted a field study, in which we investigated the effect of radiatively-induced NRW inputs on leaf water isotope signals and air–leaf water exchange in a temperate grassland during the dry-hot summers of 2018 and 2019. We carried out field measurements of the isotope composition of atmospheric water vapor, NRW droplets on foliage, leaf water, xylem water of root crown, and soil water, combined with meteorological and plant physiological measurements. We combined radiation measurements with thermal imaging to estimate leaf temperatures using different methods, and computed the corresponding leaf conductance and air–leaf water exchange. Our results indicate that radiative cooling and leaf wetting induced a switch of direction in the net water vapor exchange from leaf-to-air to air-to-leaf. The leaf conductance and air–leaf water exchange varied by species due to the species-specific biophysical controls. Our results highlight the ecological relevance of radiative cooling and leaf wetting in natural temperate grasslands, a process which is expected to influence land surface water budgets and may impact plant survival in many regions in a drier climate

Determination of a Tentative Epidemiological Cut-Off Value (ECOFF) for Dalbavancin and Enterococcus faecium

Dalbavancin is a lipoglycopeptide antibiotic that shows potent activity against Gram-positive bacteria. It circumvents vanB-type glycopeptide resistance mechanisms; however, data on the in vitro activity of dalbavancin for Enterococcus faecium (E. faecium) are scarce, and thus, no breakpoints are provided. In recent years, there has been a continuing shift from vanA-type to vanB-type vancomycin-resistance in enterococci in Central Europe. Therefore, we aimed to investigate the in vitro activity of dalbavancin against different van-genotypes, with particular focus on vanB-type E. faecium. Dalbavancin susceptibility was determined for 25 van-negative, 50 vanA-positive, and 101 vanB-positive clinical E. faecium isolates (typed by cgMLST). Epidemiological Cut-Off Values (ECOFFs) were determined using ECOFFinder. For vanB-type E. faecium isolates, dalbavancin MICs were similar to those of vancomycin-susceptible isolates reaching values no higher than 0.125 mg/L. ECOFFs for van-negative and vanB-positive isolates were 0.5 mg/l and 0.25 mg/L respectively. In contrast, E. faecium possessing vanA predominantly showed dalbavancin MICs >8 mg/L, therefore preventing the determination of an ECOFF. We demonstrated the potent in vitro activity of dalbavancin against vancomycin-susceptible and vanB-type E. faecium. On the basis of the observed wildtype distribution, a dalbavancin MIC of 0.25 mg/L can be suggested as a tentative ECOFF for E. faecium.Dalbavancin is a lipoglycopeptide antibiotic that shows potent activity against Gram-positive bacteria. It circumvents vanB-type glycopeptide resistance mechanisms; however, data on the in vitro activity of dalbavancin for Enterococcus faecium (E. faecium) are scarce, and thus, no breakpoints are provided. In recent years, there has been a continuing shift from vanA-type to vanB-type vancomycin-resistance in enterococci in Central Europe. Therefore, we aimed to investigate the in vitro activity of dalbavancin against different van-genotypes, with particular focus on vanB-type E. faecium. Dalbavancin susceptibility was determined for 25 van-negative, 50 vanA-positive, and 101 vanB-positive clinical E. faecium isolates (typed by cgMLST). Epidemiological Cut-Off Values (ECOFFs) were determined using ECOFFinder. For vanB-type E. faecium isolates, dalbavancin MICs were similar to those of vancomycin-susceptible isolates reaching values no higher than 0.125 mg/L. ECOFFs for van-negative and vanB-positive isolates were 0.5 mg/l and 0.25 mg/L respectively. In contrast, E. faecium possessing vanA predominantly showed dalbavancin MICs >8 mg/L, therefore preventing the determination of an ECOFF. We demonstrated the potent in vitro activity of dalbavancin against vancomycin-susceptible and vanB-type E. faecium. On the basis of the observed wildtype distribution, a dalbavancin MIC of 0.25 mg/L can be suggested as a tentative ECOFF for E. faecium.Peer Reviewe