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Although temporal heterogeneity is a well-accepted driver of biodiversity, effects of interannual variation in land-use intensity (LUI) have not been addressed yet. Additionally, responses to land use can differ greatly among different organisms; therefore, overall effects of land-use on total local biodiversity are hardly known. To test for effects of LUI (quantified as the combined intensity of fertilization, grazing, and mowing) and interannual variation in LUI (SD in LUI across time), we introduce a unique measure of whole-ecosystem biodiversity, multidiversity. This synthesizes individual diversity measures across up to 49 taxonomic groups of plants, animals, fungi, and bacteria from 150 grasslands. Multidiversity declined with increasing LUI among grasslands, particularly for rarer species and aboveground organisms, whereas common species and belowground groups were less sensitive. However, a high level of interannual variation in LUI increased overall multidiversity at low LUI and was even more beneficial for rarer species because it slowed the rate at which the multidiversity of rare species declined with increasing LUI. In more intensively managed grasslands, the diversity of rarer species was, on average, 18% of the maximum diversity across all grasslands when LUI was static over time but increased to 31% of the maximum when LUI changed maximally over time. In addition to decreasing overall LUI, we suggest varying LUI across years as a complementary strategy to promote biodiversity conservation.
Background
Non-invasive transcutaneous auricular vagus nerve stimulation (taVNS) has received tremendous attention as a potential neuromodulator of cognitive and affective functions, which likely exerts its effects via activation of the locus coeruleus-noradrenaline (LC-NA) system. Reliable effects of taVNS on markers of LC-NA system activity, however, have not been demonstrated yet.
Methods
The aim of the present study was to overcome previous limitations by pooling raw data from a large sample of ten taVNS studies (371 healthy participants) that collected salivary alpha-amylase (sAA) as a potential marker of central NA release.
Results
While a meta-analytic approach using summary statistics did not yield any significant effects, linear mixed model analyses showed that afferent stimulation of the vagus nerve via taVNS increased sAA levels compared to sham stimulation (b = 0.16, SE = 0.05, p = 0.001). When considering potential confounders of sAA, we further replicated previous findings on the diurnal trajectory of sAA activity.
Conclusion(s)
Vagal activation via taVNS increases sAA release compared to sham stimulation, which likely substantiates the assumption that taVNS triggers NA release. Moreover, our results highlight the benefits of data pooling and data sharing in order to allow stronger conclusions in research.
Background
Non-invasive transcutaneous auricular vagus nerve stimulation (taVNS) has received tremendous attention as a potential neuromodulator of cognitive and affective functions, which likely exerts its effects via activation of the locus coeruleus-noradrenaline (LC-NA) system. Reliable effects of taVNS on markers of LC-NA system activity, however, have not been demonstrated yet.
Methods
The aim of the present study was to overcome previous limitations by pooling raw data from a large sample of ten taVNS studies (371 healthy participants) that collected salivary alpha-amylase (sAA) as a potential marker of central NA release.
Results
While a meta-analytic approach using summary statistics did not yield any significant effects, linear mixed model analyses showed that afferent stimulation of the vagus nerve via taVNS increased sAA levels compared to sham stimulation (b = 0.16, SE = 0.05, p = 0.001). When considering potential confounders of sAA, we further replicated previous findings on the diurnal trajectory of sAA activity.
Conclusion(s)
Vagal activation via taVNS increases sAA release compared to sham stimulation, which likely substantiates the assumption that taVNS triggers NA release. Moreover, our results highlight the benefits of data pooling and data sharing in order to allow stronger conclusions in research.
Gegenstand der Arbeit ist die Beanspruchungssituation des Pflegepersonals im Krankenhausbereich. Es wird der Frage nachgegangen, mit welchem Verhaltens- und Erlebensmuster Pflegepersonen ihren Anforderungen gegenübertreten und wie sie über die Art und Weise der persönlichen Auseinandersetzung mit den Anforderungen ihre Beanspruchungsverhältnisse mitgestalten.Den theoretischen Ausgangspunkt der Arbeit bilden salutogenetisch orientierte Ressourcenmodelle, insbesondere Beckers Modell der seelischen Gesundheit (Becker, 1982, 1986). Nach ihm hängt der Gesundheitszustand einer Person davon ab, wie gut es ihr gelingt, externe und interne Anforderungen mithilfe externer und interner Ressourcen zu bewältigen. Hier knüpft das in der Arbeit im Mittelpunkt stehende diagnostische Instrument AVEM (Arbeitsbezogenes Verhaltens- und Erlebensmuster; Schaarschmidt & Fischer, 1996, 2001) an, das die Erfassung interner Anforderungen und Ressourcen der Person sowie deren Zuordnung zu 4 Verhaltens- und Erlebensmustern gegenüber der Arbeit unter Gesundheits- und Motivationsbezug ermöglicht.Mit den Hypothesen wird angenommen, dass in Anbetracht der problematischen Arbeitsbedingungen in der Pflege eine Zurücknahme im Engagement bzw. eine Schutzhaltung vor nicht gewollten und als unangemessen empfundenen Anforderungen sowie wenig beeinflussbaren Bedingungen im Vordergrund stehen. Dort, wo zumindest partiell gesundheitsförderliche und als herausfordernd erlebte Arbeitsbedingungen anzutreffen sind, sollten günstigere Musterkonstellationen auftreten. Wir vermuteten, dass sich die ungünstigen Tendenzen bereits in der Berufsausbildung und in frühen Berufsjahren zeigen. Musterveränderungen in gesundheits- und persönlichkeitsförderlicher Hinsicht sollten durch gezielte Intervention herbeigeführt werden können. Schließlich nahmen wir an, dass die Tätigkeit und die mit ihr verbundenen Anforderungen und Ausführungsbedingungen musterspezifisch wahrgenommen werden.Zur Beantwortung der Fragen werden Ergebnisse aus verschiedenen Quer- und Längsschnittuntersuchungen herangezogen, die in Wiener Spitälern und Krankenpflegeschulen, aber auch in deutschen Krankenhäusern durchgeführt wurden. Zu Vergleichszwecken werden Befunde anderer Berufsgruppen dargestellt. Neben dem AVEM wurden weitere Fragebögen zu folgenden Inhalten eingesetzt: Arbeitsbezogene Werte, Erleben von Ressourcen in der Pflegetätigkeit, Belastungserleben und Objektive Merkmale der Arbeitstätigkeit.Die Ergebnisse bestätigen die Hypothesen in allen wesentlichen Punkten. Im Vergleich mit anderen Berufsgruppen fallen für die Pflegekräfte deutliche Einschränkungen im Arbeitsengagement auf. In Bezug auf die gesundheitlichen Risikomuster nimmt das Pflegepersonal eine Mittelstellung ein. Die Musterdifferenzierung in der Pflegepopulation lässt die stärksten Unterschiede in Abhängigkeit von der Position erkennen: Je höher die Position, desto größer ist der Anteil des Gesundheitsmusters und desto geringer ist die Resignationstendenz. Die meisten Risikomuster zeigen sich bei den Pflegekräften mit der niedrigsten Qualifikation. Für Pflegeschüler ist ein zeitweiliges starkes Auftreten von resignativen Verhaltens- und Erlebensweisen sowie eine kontinuierliche Abnahme des Engagements kennzeichnend. Dieser Trend setzt sich nach Aufnahme der Berufstätigkeit fort. Nur gezielte intensive personenorientierte Interventionen erwiesen sich als geeignet, Musterveränderungen in gesundheits- und persönlichkeitsförderlicher Hinsicht zu erreichen. Die Tätigkeit und die mit ihr verbundenen Anforderungen und Ausführungsbedingungen werden musterspezifisch wahrgenommen, wobei Personen mit eingeschränktem Engagement bzw. mit einer Resignationstendenz wesentliche Tätigkeitsmerkmale, denen persönlichkeits- und gesundheitsförderliche Wirkung zugesprochen wird, für sich als wenig wichtig beurteilen und sich mehr Defizite im Verhalten gegenüber Patienten bescheinigen.Die Ergebnisse verweisen darauf, dass im Pflegeberuf vor allem die Zurückhaltung im Engagement Anlass für eine kritische Betrachtung sein muss. Das Problem "Burnout" stellt sich in seiner Bedeutung relativiert dar. Günstigere Voraussetzungen für die Aufrechterhaltung und Förderung der Gesundheit bestehen dort, wo im konkreten Arbeitsfeld ein erweiterter Tätigkeits- und Handlungsspielraum sowie mehr Verantwortung vorliegen. Diese Befunde stehen in Einklang mit arbeitspsychologischen Ressourcenmodellen. Die Befunde zu den Pflegeschülern verweisen auf teilweise ungünstige Eignungsvoraussetzungen der Auszubildenden und legen nahe, die Angemessenheit der Anforderungen in den Krankenpflegeschulen zu hinterfragen. Hinsichtlich der Möglichkeiten der Veränderung der Muster in gesundheits- und motivationsdienlicher Weise brachten die Ergebnisse zum Ausdruck, dass verhaltensbezogenen Maßnahmen ohne gleichzeitige bedingungsbezogene Interventionen wenig Erfolg beschieden ist. Mit Blick auf die musterspezifische Wahrnehmung der Tätigkeit und der mit ihr verbundenen Anforderungen und Ausführungsbedingungen ist schließlich grundsätzlich festzuhalten, dass arbeitspsychologische Konzepte, die hohen bzw. komplexen Anforderungen und umfangreichen Freiheitsgraden in der Arbeit grundsätzlich persönlichkeits- und gesundheitsförderliche Wirkungen zuschreiben, einer Relativierung durch eine differentielle Perspektive bedürfen. Die vorgefundene Interaktion von Persönlichkeit und Arbeitsbedingungen hat zur Konsequenz, dass Verhaltens- und Verhältnisprävention in untrennbarem Zusammenhang gesehen werden sollten.
Historisches Denken entwickeln am Gegenstand der altorientalischen,griechischen und römischen Antike, das ist Anliegen der didaktischen Handreichung für die gymnasiale Oberstufe. Didaktisch-methodische Überlegungen, Sachinformationen und ein handlungsorientierter Materialteil bieten für Lehrer und Schüler ein ideenreiches Angebot zur Auswahl für einen interessegeleiteten Geschichtsunterricht.
Background
High blood glucose and diabetes are amongst the conditions causing the greatest losses in years of healthy life worldwide. Therefore, numerous studies aim to identify reliable risk markers for development of impaired glucose metabolism and type 2 diabetes. However, the molecular basis of impaired glucose metabolism is so far insufficiently understood. The development of so called 'omics' approaches in the recent years promises to identify molecular markers and to further understand the molecular basis of impaired glucose metabolism and type 2 diabetes. Although univariate statistical approaches are often applied, we demonstrate here that the application of multivariate statistical approaches is highly recommended to fully capture the complexity of data gained using high-throughput methods.
Methods
We took blood plasma samples from 172 subjects who participated in the prospective Metabolic Syndrome Berlin Potsdam follow-up study (MESY-BEPO Follow-up). We analysed these samples using Gas Chromatography coupled with Mass Spectrometry (GC-MS), and measured 286 metabolites. Furthermore, fasting glucose levels were measured using standard methods at baseline, and after an average of six years. We did correlation analysis and built linear regression models as well as Random Forest regression models to identify metabolites that predict the development of fasting glucose in our cohort.
Results
We found a metabolic pattern consisting of nine metabolites that predicted fasting glucose development with an accuracy of 0.47 in tenfold cross-validation using Random Forest regression. We also showed that adding established risk markers did not improve the model accuracy. However, external validation is eventually desirable. Although not all metabolites belonging to the final pattern are identified yet, the pattern directs attention to amino acid metabolism, energy metabolism and redox homeostasis.
Conclusions
We demonstrate that metabolites identified using a high-throughput method (GC-MS) perform well in predicting the development of fasting plasma glucose over several years. Notably, not single, but a complex pattern of metabolites propels the prediction and therefore reflects the complexity of the underlying molecular mechanisms. This result could only be captured by application of multivariate statistical approaches. Therefore, we highly recommend the usage of statistical methods that seize the complexity of the information given by high-throughput methods.
Background:
Given the rising number of strokes worldwide, and the large number of individuals left with disabilities after stroke, novel strategies to reduce disability, increase functions in the motor and the cognitive domains, and improve quality of life are of major importance. Physical activity is a promising intervention to address these challenges but, as yet, there is no study demonstrating definite outcomes. Our objective is to assess whether additional treatment in the form of physical fitness-based training for patients early after stroke will provide benefits in terms of functional outcomes, in particular gait speed and the Barthel Index (co-primary outcome measures) reflecting activities of daily living (ADL). We will gather secondary functional outcomes as well as mechanistic parameters in an exploratory approach.
Methods/Design: Our phase III randomised controlled trial will recruit 215 adults with moderate to severe limitations of walking and ADL 5 to 45 days after stroke onset. Participants will be stratified for the prognostic variables of "centre", "age", and "stroke severity", and randomly assigned to one of two groups. The interventional group receives physical fitness training delivered as supported or unsupported treadmill training (cardiovascular active aerobic training; five times per week, over 4 weeks; each session 50 minutes; total of 20 additional physical fitness training sessions) in addition to standard rehabilitation treatment. The control intervention consists of relaxation sessions (non-cardiovascular active; five times per week week, over 4 weeks; each session 50 minutes) in addition to standard rehabilitation treatment. Co-primary efficacy endpoints will be gait speed (in m/s, 10 m walk) and the Barthel Index (100 points total) at 3 months post-stroke, compared to baseline measurements. Secondary outcomes include standard measures of quality of life, sleep and mood, cognition, arm function, maximal oxygen uptake, and cardiovascular risk factors including blood pressure, pulse, waist-to-hip ratio, markers of inflammation, immunity and the insulin-glucose pathway, lipid profile, and others.
Discussion: The goal of this endpoint-blinded, phase III randomised controlled trial is to provide evidence to guide post-stroke physical fitness-based rehabilitation programmes, and to elucidate the mechanisms underlying this intervention.
For improving teacher education, there has been an increasing interest in describing teachers' professional competencies and their development in the course of implementing educational programs. The focus of the present project is on modeling and measuring domain-specific and generic competencies that future physics teachers acquire during their university studies. The model comprises characteristics and relationships between physics content knowledge, pedagogical content knowledge, and skills for explaining physics phenomena. Based on the model, assessment instruments were developed and applied as paper-and-pencil-tests and videotaped expert-novice dialogues for measuring the competencies in a large sample of physics student teachers. Trials and validation suggest that our instruments are valid in terms of content and construct validities.
Teachers’ professional knowledge is assumed to be a key variable for effective teaching. As teacher education has the goal to enhance professional knowledge of current and future teachers, this knowledge should be described and assessed. Nevertheless, only a limited number of studies quantitatively measures physics teachers’ professional knowledge. The study reported in this paper was part of a bigger project with the broader goal of understanding teacher professional knowledge. We designed a test instrument to assess the professional knowledge of physics teachers (N = 186) in the dimensions of content knowledge (CK), pedagogical content knowledge (PCK), and pedagogical knowledge (PK). A model describing the relationships between these three dimensions of professional knowledge was created to inform the design of the tests used to measure CK, PCK, and PK. In this paper, we describe the model with particular emphasis on the PCK part, and the subsequent PCK test development and its implementation in detail. We report different approaches to evaluate the PCK test, including the description of content validity, the examination of the internal structure of professional knowledge, and the analysis of construct validity by testing teachers across different school subjects, teachers from different school types, pre-service teachers, and physicists. Our findings demonstrate that our PCK test results could distinguish physics teachers from the other groups tested. The PCK test results could not be explained by teachers’ CK or PK, cognitive abilities, computational skills, or science knowledge.
The relationship of different types of grassland use with plant species richness and composition ( functional groups of herbs, legumes, and grasses) has so far been studied at small regional scales or comprising only few components of land use. We comprehensively studied the relationship between abandonment, fertilization, mowing intensity, and grazing by different livestock types on plant diversity and composition of 1514 grassland sites in three regions in North-East, Central and South-West Germany. We further considered environmental site conditions including soil type and topographical situation. Fertilized grasslands showed clearly reduced plant species diversity (-15% plant species richness, -0.1 Shannon diversity on fertilized grasslands plots of 16m(2)) and changed composition (-3% proportion of herb species), grazing had the second largest effects and mowing the smallest ones. Among the grazed sites, the ones grazed by sheep had higher than average species richness (+27%), and the cattle grazed ones lower (-42%). Further, these general results were strongly modulated by interactions between the different components of land use and by regional context: land-use effects differed largely in size and sometimes even in direction between regions. This highlights the importance of comparing different regions and to involve a large number of plots
Functional biodiversity research explores drivers and functional consequences of biodiversity changes Land use change is a major driver of changes of biodiversity and of biogeochemical and biological ecosystem processes and services However, land use effects on genetic and species diversity are well documented only for a few taxa and trophic networks We hardly know how different components of biodiversity and their responses to land use change are interrelated and very little about the simultaneous, and interacting, effects of land use on multiple ecosystem processes and services Moreover, we do not know to what extent land use effects on ecosystem processes and services are mediated by biodiversity change Thus, overall goals are on the one hand to understand the effects of land use on biodiversity and on the other to understand the modifying role of biodiversity change for land-use effects on ecosystem processes, including biogeochemical cycles To comprehensively address these Important questions, we recently established a new large-scale and long-term project for functional biodiversity, the Biodiversity Exploratories (www biodiversity-exploratories de) They comprise a hierarchical set of standardized field plots in three different regions of Germany covering manifold management types and intensities in grasslands and forests They serve as a joint research platform for currently 40 projects involving over 300 people studying various aspects of the relationships between land use biodiversity and ecosystem processes through monitoring, comparative observation and experiments We introduce guiding questions, concept and design of the Biodiversity Exploratories - including main aspects of selection and implementation of field plots and project structure - and we discuss the significance of this approach for further functional biodiversity research This includes the crucial relevance of a common study design encompassing variation in both drivers and outcomes of biodiversity change and ecosystem processes, the interdisciplinary integration of biodiversity and ecosystem researchers, the training of a new generation of integrative biodiversity researchers, and the stimulation of functional biodiversity research in real landscape contexts, in Germany and elsewhere.
Vom Konflikt zur Begegnung? : Studien zu Islambildern im pädagogischen Jahrhundert Deutschlands
(2009)
There is a wealth of smaller-scale studies on the effects of forest management on plant diversity. However, studies comparing plant species diversity in forests with different management types and intensity, extending over different regions and forest stages, and including detailed information on site conditions are missing. We studied vascular plants on 1500 20 m x 20 m forest plots in three regions of Germany (Schwabische Alb, Hainich-Dun, Schorfheide-Chorin). In all regions, our study plots comprised different management types (unmanaged, selection cutting, deciduous and coniferous age-class forests, which resulted from clear cutting or shelterwood logging), various stand ages, site conditions, and levels of management-related disturbances. We analyzed how overall richness and richness of different plant functional groups (trees, shrubs, herbs, herbaceous species typically growing in forests and herbaceous light-demanding species) responded to the different management types. On average, plant species richness was 13% higher in age-class than in unmanaged forests, and did not differ between deciduous age-class and selection forests. In age-class forests of the Schwabische Alb and Hainich-Dun, coniferous stands had higher species richness than deciduous stands. Among age-class forests, older stands with large quantities of standing biomass were slightly poorer in shrub and light-demanding herb species than younger stands. Among deciduous forests, the richness of herbaceous forest species was generally lower in unmanaged than in managed forests, and it was even 20% lower in unmanaged than in selection forests in Hainich-Dun. Overall, these findings show that disturbances by management generally increase plant species richness. This suggests that total plant species richness is not suited as an indicator for the conservation status of forests, but rather indicates disturbances.
Organic management is one of the most popular strategies to reduce negative environmental impacts of intensive agriculture. However, little is known about benefits for biodiversity and potential worsening of yield under organic grasslands management across different grassland types, i.e. meadow, pasture and mown pasture. Therefore, we studied the diversity of vascular plants and foliage-living arthropods (Coleoptera, Araneae, Heteroptera, Auchenorrhyncha), yield, fodder quality, soil phosphorus concentrations and land-use intensity of organic and conventional grasslands across three study regions in Germany. Furthermore, all variables were related to the time since conversion to organic management in order to assess temporal developments reaching up to 18 years. Arthropod diversity was significantly higher under organic than conventional management, although this was not the case for Araneae, Heteroptera and Auchenorrhyncha when analyzed separately. On the contrary, arthropod abundance, vascular plant diversity and also yield and fodder quality did not considerably differ between organic and conventional grasslands. Analyses did not reveal differences in the effect of organic management among grassland types. None of the recorded abiotic and biotic parameters showed a significant trend with time since transition to organic management, except soil organic phosphorus concentrations which decreased with time. This implies that permanent grasslands respond slower and probably weaker to organic management than crop fields do. However, as land-use intensity and inorganic soil phosphorus concentrations were significantly lower in organic grasslands, overcoming seed and dispersal limitation by re-introducing plant species might be needed to exploit the full ecological potential of organic grassland management. We conclude that although organic management did not automatically increase the diversity of all studied taxa, it is a reasonable and useful way to support agro-biodiversity.
Awards
(2013)