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Hintergrund
Immer mehr pflegebedĂŒrftige Menschen werden in der HĂ€uslichkeit durch informell Pflegende zusammen mit ambulanten Pflegediensten versorgt. Die drei Konzepte âPflegebedĂŒrftigkeitâ, âGesundheitâ und âKrankheitâ spielen in diesem Kontext eine besondere Rolle. Ăber keines dieser Konzepte besteht definitorische Einigkeit; die Termini werden je nach Kontext bzw. Zweck unterschiedlich verstanden. Empirische Sozialforschung, Medizintheorie sowie Medizin- und Pflegeethik beschĂ€ftigen sich intensiv â jedoch getrennt voneinander â mit ihren Inhalten und ethischen Implikationen. Den drei Konzepten ist gemeinsam, dass deren subjektives VerstĂ€ndnis und normative Implikationen in der ambulanten Pflege bisher nur unzureichend analysiert wurde.
Methoden
In einem dreigliedrigen Projekt bestand der erste Schritt in einer Literaturrecherche mit Analyseschwerpunkt zu medizin- und pflegeethischen sowie medizintheoretischen Konzepten im wissenschaftlichen Diskurs zu Gesundheits- und Krankheitsvorstellungen. Ausgehend davon wurden die Forschungsfrage und - methode festgelegt. In einem zweiten Schritt erfolgte die empirische Exploration subjektiver Perspektiven professionell Pflegender, PflegebedĂŒrftiger und informell Pflegender auf PflegebedĂŒrftigkeit, Gesundheit und Krankheit in hĂ€uslichen Langzeitpflegearrangements mit Hilfe qualitativer Leitfadeninterviews. Die Auswertung der Transkripte wurde mittels qualitativer Inhaltsanalyse vorgenommen. Um Implikationen fĂŒr die empirische Sozialforschung, Medizintheorie sowie Medizin- und Pflegeethik entwickeln zu können, fĂŒhrte ein dritter Schritt die empirischen und normativen Perspektiven zusammen.
Ergebnisse
Die Studie liefert empirische Ergebnisse zu den subjektiven Vorstellungen und Wahrnehmungen professionell Pflegender, PflegebedĂŒrftiger und informell Pflegender hinsichtlich der Angemessenheit der Versorgung (1), den Vorstellungen von Gesundheit (2) und den Belastungen, die aus der hĂ€uslichen Pflegesituation resultieren (3). Zudem werden die Ergebnisse der empirisch-ethischen Analyse zu Spannungsfeldern zwischen subjektivem KrankheitsgefĂŒhl (âIllnessâ) und anhand objektiver Kriterien festgestellter Krankheit (âDiseaseâ) geschildert und die Grenzen der moralischen Verpflichtungen zur PflegeĂŒbernahme in der ambulanten Pflege abgesteckt.
Diskussion
Ein Vergleich der empirischen Ergebnisse mit existierenden normativen LeitfĂ€den offenbart eine Diskrepanz zwischen Ist- und Sollzustand. Es wird die Bedeutung fĂŒr die Praxis der empirischen Sozialforschung sowie der Medizintheorie und Medizin- und Pflegeethik abgeleitet.
Die vorliegende Arbeit untersucht eine individualisierte und schĂŒlerzentrierte Lernumgebung auf der Basis von Kompetenzrastern und vergleicht diese mit einem konventionellen lehrergefĂŒhrten Unterricht. Der erste Teil der vorliegenden Dissertation beschreibt die Entwicklung der Lernumgebung und skizziert die theoretischen HintergrĂŒnde der motivationalen Entwicklung von SchĂŒler*innen. AnschlieĂend vergleichen drei Studien beide Lernumgebungen hinsichtlich der motivationalen Variablen und des Zusammenspiels dieser, um einerseits beide Lernumgebung zu evaluieren und andererseits PrĂ€diktoren von Motivation und Lernverhalten zu untersuchen. Alle drei Studien basieren auf einer Stichprobe von 1,153 SchĂŒlerinnen und SchĂŒlern im Alter von 12 bis 18 Jahren (M = 13.97, SD = 1.37, 49% MĂ€dchen).
Studie 1 untersucht, ob wahrgenommene Autonomie die Beziehung von Selbstwirksamkeit einerseits und der Lernstrategienutzung anderseits mediiert. Latente Mittelwertsvergleiche und Mehrgruppen-Mehrebenen-Strukturgleichungsmodelle wurden durchgefĂŒhrt um die Hypothesen zu untersuchen. Die Ergebnisse legen nahe, dass wahrgenommene AutonomieunterstĂŒtzung die Beziehung zwischen Selbstwirksamkeit und Lernstrategien mediiert, allerdings ausschlieĂlich fĂŒr SchĂŒlerinnen und SchĂŒler in der schĂŒlerzentrierten Lernumgebung auf der Basis von Kompetenzrastern.
Studie 2 untersucht, ob KompetenzunterstĂŒtzung die Beziehung vom akademischen Selbstkonzept und der Leistungsmotivation unterschiedlich fĂŒr SchĂŒlerinnen und SchĂŒler aus einer lehrergefĂŒhrten und einer schĂŒlerzentrierten Lernumgebung auf der Basis von Kompetenzrastern mediiert. Latente Mittelwertsvergleiche und Mehrgruppen-Strukturgleichungsmodelle wurden konzipiert, um die Hypothesen zu untersuchen. Die Mehrgruppen-Strukturgleichungsmodelle zeigen, dass KompetenzunterstĂŒtzung ausschlieĂlich in der schĂŒlerzentrierten Lernumgebung auf der Basis von Kompetenzrastern die Beziehung vom akademischen Selbstkonzept und der Leistungsmotivation mediiert, vor allem fĂŒr SchĂŒlerinnen und SchĂŒler in der frĂŒhen Adoleszenz.
Studie 3 untersucht den reziproken Zusammenhang zwischen Leistungsemotionenn und selbstbestimmter Motivation. Latente Mittelwertsvergleiche und autoregressive cross-lagged Panel Analysen wurden durchgefĂŒhrt, um die Hypothesen zu untersuchen. Reziproke Beziehungenn wurden nicht nachgewiesen. Allerdings konnte aufgezeigt werden, dass ausschlieĂlich in der schĂŒlerzentrierten Lernumgebung auf der Basis von Kompetenzrastern positive Leistungsemotionen (i.e., Lernfreude) selbstbestimmte Formen der Motivation vorhersagen.
Die vorliegende Arbeit wird abgeschlossen durch eine Zusammenfassung der Ergebnisse, praktische Implikationen fĂŒr die Schulpraxis, sowie durch ein Limitationskapitel.
Der Fokus meiner Dissertation lag auf der genauen Charakterisierung epileptischer AnfĂ€lle eines klar definierten Patientenkollektivs mit spĂ€t manifestierender (â„ 55. Lebensjahr) nicht-lĂ€sioneller Epilepsie (nonlesional late-onset epilepsy, NLLOE). Erstmalig wurden semiologische Merkmale der epileptischen AnfĂ€lle in dieser Kohorte systematisch untersucht und entsprechend des neusten Klassifikationssystems der Internationalen League Against Epilepsy von 2017 eingeordnet. Die Kohorte umfasste 54 Patienten, von denen zusĂ€tzlich EEG- und Liquordaten im Rahmen ihrer Behandlung am Epilepsiezentrum der UniversitĂ€tsmedizin Greifswald erhoben und mit einer Kontrollkohorte verglichen wurden. Diese setzte sich aus 58 Patienten mit frĂŒh beginnender nicht-lĂ€sioneller Epilepsie (nonlesional early-onset epilepsy, NLEOE) zusammen. Ein weiterer wesentlicher Aspekt meiner Dissertation war die ĂberprĂŒfung des Behandlungserfolges nach 12-monatiger antikonvulsiver Therapie in der NLLOE-Kohorte.
Die durchgefĂŒhrte Studie zeigte bei Patienten mit spĂ€t manifestierender nicht-lĂ€sioneller Epilepsie ein im Vergleich zur Kontrollkohorte signifikant hĂ€ufigeres Auftreten von focal onset impaired awareness non-motor seizures. Diese manifestierten sich insbesondere in Form von passageren BeeintrĂ€chtigungen der Kognition und sensorischen Auren. Im Liquor der NLLOE-Patienten konnten bei drei Patienten oligoklonale Banden nachgewiesen werden. Bei einem dieser Patienten wurde im Nachhinein eine autoimmune Enzephalitis als Ursache der Epilepsie postuliert. Ferner waren 70% der NLLOE-Patienten nach einem Beobachtungszeitraum von 12 Monaten anfallsfrei. Den besten Behandlungserfolg, jedoch auch die höchste Nebenwirkungsrate, wurde mit dem Antikonvulsivum Levetiracetam erzielt.
Diese Ergebnisse machen deutlich, dass bei NLLOE-Patienten durch das Fehlen charakteristischer und leicht erkennbarer motorischer Symptome eine genaue Charakterisierung auch anderer semiologischer Merkmale unabdingbar ist, um gerade in dieser Patientengruppe epileptische AnfĂ€lle sicher identifizieren und eine adĂ€quate Therapie einleiten zu können. Die Liquoranalyse deutet zudem daraufhin, dass systematische Antikörpertestungen im Liquor und Serum als weiterfĂŒhrende diagnostische MaĂnahme zum Ausschluss einer autoimmunen Genese einer Epilepsie berĂŒcksichtigt werden sollten. DarĂŒber hinaus belegen die Resultate ein gutes therapeutisches Ansprechen der medikamentösen antikonvulsiven Therapie bei Patienten mit nicht-lĂ€sioneller Epilepsie im höheren Lebensalter.
In this thesis, I present work motivated, in part, by a series of upcoming laboratory experiments (APEX), which seeks to uncover some of the inner workings of turbulence and stability in electron- positron plasmas in closed field-line systems. I present the results of several distinct, but connected, problems addressing the theory of electron-positron plasmas.
This work is partitioned into several parts, which loosely correspond to different particulars of the APEX experiment and the different theoretical physics problems which reside within.
I begin with the derivation of a kinetic theory for plasmas which are optically thin to cyclotron emission, as indeed, experimental pair plasmas are expected to be. The results of this section include: (1) the derivation of a general kinetic theory of cyclotron radiation in electron-ion plasmas; (2) a calculation showing that cyclotron emission results in strongly anisotropic distribution functions on the radiation timescale; (3) calculation of the evolution of the distribution function under collisional scattering which, in the absence of any radiation terms, acts to drive the plasma towards a Maxwellian; (4) generalisation of this theory to more exotic geometries; (5) specialisation of this theory to pair plasmas of experimental interest; and (6) presentation of the applications and the limitations of this theory.
The second project is primarily concerned with non-neutral plasmas. We begin with gyrokinetic theory and a novel extension of this theoretical framework to plasmas with arbitrary degree of neutrality in straight field-line geometry. I go on to discuss the gyrokinetic stability theory of such plasmas in this simplified geometry. I conclude this project with a discussion of some further
nuances in the theory of singly-charged non-neutral plasmas, this time concerning global features. Namely, I declare an interest in the equilibria such plasmas might be able to attain.
The final project pertains to plasmas which are in state of Maxwellian equilibrium i.e., electron- positron plasmas with sufficiently large number densities of each species to attain a stationary quasineutral plasma. To this end, I present gyrokinetic flux-tube simulations of electron-positron plasmas in complex, and experimentally relevant, magnetic geometries on the road towards a study of gyrokinetic turbulence. The results of this work include: (1) the first simulations of electron- positron plasmas in a stellarator and ring-dipole geometry; (2) an analytic theory of trapped particle modes in electron-positron plasmas, a result which can also be verified numerically; and (3) extension of several important theoretical results in electron-positron plasmas to experimentally relevant geometries. The culmination of this project is the roadmap ahead towards demonstration of the so-called âinward pinchâ effect in electron-positron plasmas in a magnetic Z-pinch.
G-quadruplexes (G4s) have been in the focus of research in the last decades for their regulatory roles in vivo and for their use in nano- and biotechnology. However, an understanding of the various factors that drive a particular quadruplex fold remains limited, challenging rational therapeutic targeting and design of these tetrahelical structures. In this regard, insights from modified G-quadruplexes may help to deepen our knowledge of G-quadruplex structure. In this dissertation, sugar-modified guanosine analogs are exploited for their altered conformational preferences regarding both glycosidic bond angle and sugar pucker by their incorporation into different syn positions of the G-core of a model G-quadruplex. Induced structural perturbations as characterized by NMR spectroscopy range from a local change in tetrad polarity to a complete refolding into an unusual structure with a V-shaped loop, a unique G4 structural element in the focus of this work. Detailed conformational analysis of the introduced G analogs and high-resolution structures of the modified quadruplexes reveal a complex interplay of glycosidic torsion angle, sugar pucker preferences and local interactions, which may all play a leading role in driving G4 folding.
Global climate change is omnipresent all over the world and is affecting and challenging organisms in various ways. Species either have to adapt to the changing environmental conditions or move to new habitats in order to avoid extinction.
Possible ways for an organism to react can be dispersal, phenotypic plasticity, genetic adaptation or a combination of these factors. Among the various consequences of climate change, especially changes in temperature affect plenty of species. In ectotherms, the body temperature and associated mechanisms are strongly dependent on environmental conditions.
The aim of this work was to investigate the mechanisms underlying adaptation to thermal variation and heat stress in the widespread butterfly species <i>Pieris napi<i>.
Focusing on indicators of individual condition, including morphology, physiology and life history traits, the purpose was to specify whether the speciesâ responses to temperature variation have a plastic or genetic basis. In the first experiment, phenotypic variation along a latitudinal and altitudinal cline was investigated. Yellow reflectance of wings was negatively correlated with wing melanisation, providing evidence for a trade-off between a sexually selected trait (yellow color) and thermoregulation (black color). Body size decreased with increasing latitude and led to the assumption that warmer conditions are more beneficial for <i>P. napi<i> than cooler ones. An increased flight performance at higher altitudes but not latitudes may
indicate stronger challenges for flight activity in high-altitude environments.
The second experiment focused on clinal variation and plasticity in morphology, physiology and life history in F1-generation individuals reared in captivity at different temperatures. It could be shown that individuals from cooler environments were less heat-tolerant, had a longer development but were nevertheless smaller, and had more melanised wings. These differences were genetically-based. Furthermore, it could be shown that a higher developmental temperature speeded up development, reduced body size, potential metabolic activity, and wing melanisation but increased heat tolerance, documenting plastic responses.
In a third experiment, we examined physiological responses to heat stress. A transcriptome analysis revealed an upregulation in molecular chaperones under hot conditions, whereas antioxidant responses and oxidative damage remained unaffected. The antioxidant glutathione (GSH) though was reduced under both cold and hot conditions. Interestingly, Swedish individuals were characterized by higher levels of GSH, lower early fecundity, and lower larval growth rates compared with German or Italian populations, suggesting a âpace-of-lifeâ syndrome. Thus, the individuals from warmer regions show the opposite pattern with a lower investment into maintenance but a faster lifestyle.
In summary, we found clinal variation in body size, growth rates and concomitant development time, wing aspect ratio, wing melanisation and heat tolerance. The effects of high developmental temperature very likely reflect adaptive phenotypic plasticity. When speeding up development; heat tolerance is increasing while body size, potential metabolic activity and wing melanisation are decreasing. Overall, body size of <i>P. napi<i> individuals decreased from south to north while the melanisation of the wings increased. Furthermore, we found a connection between increased wing melanisation and decreased yellow reflectance, most likely caused by a trade-off between the two. We could confirm that <i>P. napi<i> individuals from warmer environments were more heat-tolerant and larger than individuals from colder environments. Due to increasing temperatures and heat waves becoming more frequent in the future, being able to cope with such conditions will be advantageous. As warmer conditions had positive effects on individual development, <i>P. napi<i> may benefit from global warming, but its association with moist habitats suggests negative consequences of climate change. We could also reveal pronounced plastic and genetic responses in <i>P. napi<i>, which may indicate high adaptive capacities. Thus, increasing temperature may not be too problematic for the species, as it seems to be rather well equipped to deal with such challenges. However, as climate change entails changes in precipitation / humidity along with temperature changes, such issues need further investigation.
Abstract
In crisis communication, warning messages are key to prevent or mitigate damage by informing the public about impending risks and hazards. The present study explored the influence of hazard type, trait anxiety, and warning message on different components of risk perception. A survey examined 614 German participants (18â96 years, M = 31.64, 63.0% female) using a preâpost comparison. Participants were randomly allocated to one of five hazards (severe weather, act of violence, breakdown of emergency number, discovery of a World War II bomb, or major fire) for which they received a warning message. Four components of risk perception (perceived severity, anticipatory worry, anticipated emotions, and perceived likelihood) were measured before and after the receipt. Also, trait anxiety was assessed. Analyses of covariance of risk perception were calculated, examining the effect of warning message, trait anxiety, and hazard type while controlling for age, gender, and previous hazard experience. Results showed main effects of hazard type and trait anxiety on every component of risk perception, except for perceived likelihood. The receipt of a warning message led to a significant decrease in anticipated negative emotions. However, changes across components of risk perception, as well as hazards, were inconsistent, as perceived severity decreased while perceived likelihood and anticipatory worry increased. In addition, three interactional effects were found (perceived severity Ă hazard type, perceived severity Ă trait anxiety, and anticipated emotions Ă hazard type). The findings point toward differences in the processing of warning messages yet underline the importance of hazard type, as well as characteristics of the recipient.
Abstract
The expected signature is an analogue of the Laplace transform for probability measures on rough paths. A key question in the area has been to identify a general condition to ensure that the expected signature uniquely determines the measures. A sufficient condition has recently been given by Chevyrev and Lyons and requires a strong upper bound on the expected signature. While the upper bound was verified for many wellâknown processes up to a deterministic time, it was not known whether the required bound holds for random time. In fact, even the simplest case of Brownian motion up to the exit time of a planar disc was open. For this particular case we answer this question using a suitable hyperbolic projection of the expected signature. The projection satisfies a threeâdimensional system of linear PDEs, which (surprisingly) can be solved explicitly, and which allows us to show that the upper bound on the expected signature is not satisfied.
In Germany, basic data on the biology, ecology and distribution of rare mosquito species are insufficiently recorded leading to knowledge gaps, for example regarding their vector potential. The introduction of new mosquito species and of the pathogens they transmit has increased the risk of diseases previously uncommon in Germany. These circumstances have led to increased efforts within the past 10 years to better understand the spatio-temporal occurrence and underlying habitat binding of mosquito species and to predict their future distribution, particularly with regard to the changing climatic conditions and changing landscape. A reliable morphological and genetic identification was lacking for several native mosquito species, which forms the basis for any robust monitoring within mosquito surveillance programs or insect conservation projects.
The aim of this thesis was to gain detailed knowledge on the current spatial and temporal occurrence, the habitat binding, and morphological and genetic features with regard to species identification for the non-native species Aedes albopictus (Skuse, 1895), the native species of the Aedes Annulipes Group, and the native and rare species Aedes refiki Medschid, 1928, Culex martinii Medschid, 1930 and Culiseta ochroptera (Peus, 1935).
The thesis compares the suitability of the local climate for the persistence of the species Aedes albopictus sporadically observed in Jena (Thuringia) from 2015 to 2018 with two populations in southern Germany. The focus was on the analysis of extreme winter temperatures and the duration below selected temperature thresholds. In addition to critical temperature conditions, aquatic habitat conditions were of importance. The results of this study suggest that the population could become established in the long term.
Through the monitoring conducted for this thesis, the very rare mosquito species Aedes refiki, Culex martinii in Thuringia and Culiseta ochroptera were rediscovered at several sites in northern and eastern Germany. It was possible to add new information on habitat binding, distribution and abundance for the considered mosquito species. The survival of these rare native mosquito species depends on the preservation of a few remaining habitats. In addition, it can be assumed that these species will become even rarer with future climate change in Germany and, therefore, should be considered endangered. In contrast, other mosquito species could benefit from an increase in average temperatures or precipitation in individual cases.
Due to the contribution to species identification, difficulties in the morphological and genetic identification of selected mosquito species native to Germany could be dispelled. Three forms each were assigned to the known morphological variants of Aedes refiki and Culiseta ochroptera and their peculiarities were described, as well as a new character for species identification was highlighted in the case of Culiseta ochroptera. Generated CO1 mtDNA sequences provide the first DNA-barcodes of Aedes refiki and Culex martinii for Germany.
In five native mosquito species of the Aedes Annulipes Group, twenty types of aberrant tarsal claws were illustrated and described in their morphology. Morphological peculiarities and an asymmetrical occurrence of the aberrant claw types were observed and possible causes for their development were discussed. Together with the development of a basic blueprint of mosquito tarsal claws, the results opened another field of research for the taxonomy, developmental biology and aquatic ecology of arthropods.
Abstract
Aerated topsoils are important sinks for atmospheric methane (CH4) via oxidation by CH4âoxidizing bacteria (MOB). However, intensified management of grasslands and forests may reduce the CH4 sink capacity of soils. We investigated the influence of grassland landâuse intensity (150 sites) and forest management type (149 sites) on potential atmospheric CH4 oxidation rates (PMORs) and the abundance and diversity of MOB (with qPCR) in topsoils of three temperate regions in Germany. PMORs measurements in microcosms under defined conditions yielded approximately twice as much CH4 oxidation in forest than in grassland soils. High landâuse intensity of grasslands had a negative effect on PMORs (â40%) in almost all regions and fertilization was the predominant factor of grassland landâuse intensity leading to PMOR reduction by 20%. In contrast, forest management did not affect PMORs in forest soils. Upland soil cluster (USC)âα was the dominant group of MOBs in the forests. In contrast, USCâÎł was absent in more than half of the forest soils but present in almost all grassland soils. USCâα abundance had a direct positive effect on PMOR in forest, while in grasslands USCâα and USCâÎł abundance affected PMOR positively with a more pronounced contribution of USCâÎł than USCâα. Soil bulk density negatively influenced PMOR in both forests and grasslands. We further found that the response of the PMORs to pH, soil texture, soil water holding capacity and organic carbon and nitrogen content differ between temperate forest and grassland soils. pH had no direct effects on PMOR, but indirect ones via the MOB abundances, showing a negative effect on USCâα, and a positive on USCâÎł abundance. We conclude that reduction in grassland landâuse intensity and afforestation has the potential to increase the CH4 sink function of soils and that different parameters determine the microbial methane sink in forest and grassland soils.