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Context
For a given body mass index (BMI), both impaired metabolic health (MH) and reduced cardiorespiratory fitness (CRF) associate with increased risk of cardiovascular disease (CVD).
Objective
It remains unknown whether both risk phenotypes relate to CVD independently of each other, and whether these relationships differ in normal weight, overweight, and obese subjects.
Methods
Data from 421 participants from the Tubingen Diabetes Family Study, who had measurements of anthropometrics, metabolic parameters, CRF (maximal aerobic capacity [VO2max]) and carotid intima-media thickness (cIMT), an early marker of atherosclerosis, were analyzed. Subjects were divided by BMI and MH status into 6 phenotypes.
Results
In univariate analyses, older age, increased BMI, and a metabolic risk profile correlated positively, while insulin sensitivity and VO2max negatively with cIMT. In multivariable analyses in obese subjects, older age, male sex, lower VO2max (std. ss -0.21, P = 0.002) and impaired MH (std. ss 0.13, P = 0.02) were independent determinants of increased cIMT. After adjustment for age and sex, subjects with metabolically healthy obesity (MHO) had higher cIMT than subjects with metabolically healthy normal weight (MHNW; 0.59 +/- 0.009 vs 0.52 +/- 0.01 mm; P < 0.05). When VO2max was additionally included in this model, the difference in cIMT between MHO and MHNW groups became statistically nonsignificant (0.58 +/- 0.009 vs 0.56 +/- 0.02 mm; P > 0.05).
Conclusion
These data suggest that impaired MH and low CRF independently determine increased cIMT in obese subjects and that low CRF may explain part of the increased CVD risk observed in MHO compared with MHNW.
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.
BIOMEX (BIOlogy and Mars EXperiment) is an ESA/Roscosmos space exposure experiment housed within the exposure facility EXPOSE-R2 outside the Zvezda module on the International Space Station (ISS). The design of the multiuser facility supports-among others-the BIOMEX investigations into the stability and level of degradation of space-exposed biosignatures such as pigments, secondary metabolites, and cell surfaces in contact with a terrestrial and Mars analog mineral environment. In parallel, analysis on the viability of the investigated organisms has provided relevant data for evaluation of the habitability of Mars, for the limits of life, and for the likelihood of an interplanetary transfer of life (theory of lithopanspermia). In this project, lichens, archaea, bacteria, cyanobacteria, snow/permafrost algae, meristematic black fungi, and bryophytes from alpine and polar habitats were embedded, grown, and cultured on a mixture of martian and lunar regolith analogs or other terrestrial minerals. The organisms and regolith analogs and terrestrial mineral mixtures were then exposed to space and to simulated Mars-like conditions by way of the EXPOSE-R2 facility. In this special issue, we present the first set of data obtained in reference to our investigation into the habitability of Mars and limits of life. This project was initiated and implemented by the BIOMEX group, an international and interdisciplinary consortium of 30 institutes in 12 countries on 3 continents. Preflight tests for sample selection, results from ground-based simulation experiments, and the space experiments themselves are presented and include a complete overview of the scientific processes required for this space experiment and postflight analysis. The presented BIOMEX concept could be scaled up to future exposure experiments on the Moon and will serve as a pretest in low Earth orbit.
Background Anxiety and depressive disorders share common features of mood dysfunctions. This has stimulated interest in transdiagnostic dimensional research as proposed by the Research Domain Criteria (RDoC) approach by the National Institute of Mental Health (NIMH) aiming to improve the understanding of underlying disease mechanisms. The purpose of this study was to investigate the processing of RDoC domains in relation to disease severity in order to identify latent disorder-specific as well as transdiagnostic indicators of disease severity in patients with anxiety and depressive disorders.
Methods Within the German research network for mental disorders, 895 participants (n = 476 female, n = 602 anxiety disorder, n = 257 depressive disorder) were recruited for the Phenotypic, Diagnostic and Clinical Domain Assessment Network Germany (PD-CAN) and included in this cross-sectional study. We performed incremental regression models to investigate the association of four RDoC domains on disease severity in patients with affective disorders: Positive (PVS) and Negative Valance System (NVS), Cognitive Systems (CS) and Social Processes (SP).
Results The results confirmed a transdiagnostic relationship for all four domains, as we found significant main effects on disease severity within domain-specific models (PVS: & beta; = -0.35; NVS: & beta; = 0.39; CS: & beta; = -0.12; SP: & beta; = -0.32). We also found three significant interaction effects with main diagnosis showing a disease-specific association.
Limitations The cross-sectional study design prevents causal conclusions. Further limitations include possible outliers and heteroskedasticity in all regression models which we appropriately controlled for.
Conclusion Our key results show that symptom burden in anxiety and depressive disorders is associated with latent RDoC indicators in transdiagnostic and disease-specific ways.
This study aimed to build on the relationship of well-established self-report and behavioral assessments to the latent constructs positive (PVS) and negative valence systems (NVS), cognitive systems (CS), and social processes (SP) of the Research Domain Criteria (RDoC) framework in a large transnosological population which cuts across DSM/ICD-10 disorder criteria categories. One thousand four hundred and thirty one participants (42.1% suffering from anxiety/fear-related, 18.2% from depressive, 7.9% from schizophrenia spectrum, 7.5% from bipolar, 3.4% from autism spectrum, 2.2% from other disorders, 18.4% healthy controls, and 0.2% with no diagnosis specified) recruited in studies within the German research network for mental disorders for the Phenotypic, Diagnostic and Clinical Domain Assessment Network Germany (PD-CAN) were examined with a Mini-RDoC-Assessment including behavioral and self-report measures. The respective data was analyzed with confirmatory factor analysis (CFA) to delineate the underlying latent RDoC-structure. A revised four-factor model reflecting the core domains positive and negative valence systems as well as cognitive systems and social processes showed a good fit across this sample and showed significantly better fit compared to a one factor solution. The connections between the domains PVS, NVS and SP could be substantiated, indicating a universal latent structure spanning across known nosological entities. This study is the first to give an impression on the latent structure and intercorrelations between four core Research Domain Criteria in a transnosological sample. We emphasize the possibility of using already existing and well validated self-report and behavioral measurements to capture aspects of the latent structure informed by the RDoC matrix.
Supermassive black holes are a fundamental component of the universe in general and of galaxies in particular. Almost every massive galaxy harbours a supermassive black hole (SMBH) in its center. Furthermore, there is a close connection between the growth of the SMBH and the evolution of its host galaxy, manifested in the relationship between the mass of the black hole and various properties of the galaxy's spheroid component, like its stellar velocity dispersion, luminosity or mass. Understanding this relationship and the growth of SMBHs is essential for our picture of galaxy formation and evolution. In this thesis, I make several contributions to improve our knowledge on the census of SMBHs and on the coevolution of black holes and galaxies. The first route I follow on this road is to obtain a complete census of the black hole population and its properties. Here, I focus particularly on active black holes, observable as Active Galactic Nuclei (AGN) or quasars. These are found in large surveys of the sky. In this thesis, I use one of these surveys, the Hamburg/ESO survey (HES), to study the AGN population in the local volume (z~0). The demographics of AGN are traditionally represented by the AGN luminosity function, the distribution function of AGN at a given luminosity. I determined the local (z<0.3) optical luminosity function of so-called type 1 AGN, based on the broad band B_J magnitudes and AGN broad Halpha emission line luminosities, free of contamination from the host galaxy. I combined this result with fainter data from the Sloan Digital Sky Survey (SDSS) and constructed the best current optical AGN luminosity function at z~0. The comparison of the luminosity function with higher redshifts supports the current notion of 'AGN downsizing', i.e. the space density of the most luminous AGN peaks at higher redshifts and the space density of less luminous AGN peaks at lower redshifts. However, the AGN luminosity function does not reveal the full picture of active black hole demographics. This requires knowledge of the physical quantities, foremost the black hole mass and the accretion rate of the black hole, and the respective distribution functions, the active black hole mass function and the Eddington ratio distribution function. I developed a method for an unbiased estimate of these two distribution functions, employing a maximum likelihood technique and fully account for the selection function. I used this method to determine the active black hole mass function and the Eddington ratio distribution function for the local universe from the HES. I found a wide intrinsic distribution of black hole accretion rates and black hole masses. The comparison of the local active black hole mass function with the local total black hole mass function reveals evidence for 'AGN downsizing', in the sense that in the local universe the most massive black holes are in a less active stage then lower mass black holes. The second route I follow is a study of redshift evolution in the black hole-galaxy relations. While theoretical models can in general explain the existence of these relations, their redshift evolution puts strong constraints on these models. Observational studies on the black hole-galaxy relations naturally suffer from selection effects. These can potentially bias the conclusions inferred from the observations, if they are not taken into account. I investigated the issue of selection effects on type 1 AGN samples in detail and discuss various sources of bias, e.g. an AGN luminosity bias, an active fraction bias and an AGN evolution bias. If the selection function of the observational sample and the underlying distribution functions are known, it is possible to correct for this bias. I present a fitting method to obtain an unbiased estimate of the intrinsic black hole-galaxy relations from samples that are affected by selection effects. Third, I try to improve our census of dormant black holes and the determination of their masses. One of the most important techniques to determine the black hole mass in quiescent galaxies is via stellar dynamical modeling. This method employs photometric and kinematic observations of the galaxy and infers the gravitational potential from the stellar orbits. This method can reveal the presence of the black hole and give its mass, if the sphere of the black hole's gravitational influence is spatially resolved. However, usually the presence of a dark matter halo is ignored in the dynamical modeling, potentially causing a bias on the determined black hole mass. I ran dynamical models for a sample of 12 galaxies, including a dark matter halo. For galaxies for which the black hole's sphere of influence is not well resolved, I found that the black hole mass is systematically underestimated when the dark matter halo is ignored, while there is almost no effect for galaxies with well resolved sphere of influence.
1. Problemstellung Die Liberalisierung von Netzindustrien stellt eine volkswirtschaftliche Problematik dar, die einerseits eine Vielzahl theoretisch ungelöster Fragen aufwirft und für die andererseits nunmehr auch in Deutschland wirtschaftspolitische Erfahrungen vorliegen. Die Ursachen der ökonomischen Probleme sind dabei nicht nur in bestimmten Branchenbesonderheiten der Netzindustrien zu suchen, sondern auch in einer verfehlten ordnungspolitischen Sonderbehandlung der netzgebundenen Wirtschaftsbereiche in der Vergangenheit. Entgegen den für eine marktwirtschaftliche Ordnung charakteristischen Prinzipien Wettbewerb und Privateigentum wurden Netzindustrien traditionell als wettbewerbliche Ausnahmebereiche behandelt und zumeist in Form öffentlicher Unternehmen geführt. Die Folge dessen waren (staatliche) Monopole, die eine relativ hohe Ineffizienz aufwiesen. Die ordnungspolitische Konsequenz dieses Befundes lautete daher Liberalisierung von Netzindustrien durch Privatisierung und Marktöffnung, d. h. ein Abbau von Marktzutrittsschranken durch Deregulierung. Wettbewerb stößt in Netzindustrien jedoch an Grenzen, weil die zur Produktion netzgebundener Dienstleistungen erforderliche Infrastruktur typischerweise ein nicht-angreifbares, natürliches Monopol darstellt, das sich in der Hand eines im Markt eingesessenen, vertikal integrierten Anbieters befindet. Daraus ergeben sich weitreichende Möglichkeiten zur Diskriminierung von Konkurrenten, die wettbewerbspolitischen Handlungsbedarf nach sich ziehen. Diesen gilt es in der vorliegenden Arbeit zu analysieren und alternative Lösungsansätze der Diskriminierungsproblematik zu diskutieren. 2. Besonderes Forschungsziel Die vorliegende Dissertation widmet sich der Liberalisierung von Netzindustrien aus ökonomischer Sicht, wobei insbesondere die Interdependenzen zwischen der Eigentums- und der Diskriminierungsproblematik berücksichtigt werden. Gleichwohl bildet die wettbewerbliche Öffnung der Märkte für netzgebundene Dienstleistungen aus volkswirtschaftlicher Sicht das Kernproblem und somit auch den zentralen Untersuchungsgegenstand dieser Arbeit. Die theoretische Analyse bleibt dabei nicht auf einen Forschungsansatz beschränkt, sondern es werden mehrere Facetten der Liberalisierung von der Ordnungs- über die Netzökonomik bis hin zur politischen Ökonomie betrachtet. In empirischer Hinsicht haben die in Deutschland in verschiedenen Netzindustrien realisierten Marktöffnungen bislang zu unterschiedlich intensiven Wettbewerbsprozessen geführt. Daher wird ein problemorientierter, intersektoraler Vergleich der Reformen und eine wettbewerbs-politische Beurteilung anhand der drei Marktmerkmale Marktstruktur, Marktverhalten und Marktergebnis vorgenommen, um die Liberalisierung in einzelnen Netzindustrien zu bewerten. Die Telekommunikation gilt dabei als Musterbeispiel für eine erfolgreiche Liberalisierung, weil die Deregulierung hier durch eine sektorspezifische Marktmachtkontrolle begleitet wird, wofür eigens eine Regulierungsbehörde geschaffen wurde. Vor diesem Hintergrund wird der mangelnde Wettbewerb in der Strom- und vor allem in der Gasversorgung sowie im Schienenverkehr häufig auf das Fehlen solcher Institutionen zurückgeführt. Aufgrund dessen werden hier die Eisenbahn, die Telekommunikation im Festnetz und die leitungsgebundene Energieversorgung als empirische Analyseobjekte ausgewählt, um die im Laufe der Untersuchung gewonnenen theoretischen Erkenntnisse exemplarisch an diesen Netzindustrien aufzuzeigen und die im Folgenden formulierte Arbeitshypothese zu überprüfen. 3. Methodik Die Arbeit gliedert sich in einen theoretischen und einen empirischen Teil. Die theoretisch zu untersuchende Frage bei der Liberalisierung von Netzindustrien lautet: Welcher institutionellen Arrangements bedarf es in Netzindustrien, um vormals monopolistisch organisierte in kompetitive Märkte zu überführen und darin nachhaltig einen effektiven Wettbewerb zu etablieren? Auf der Grundlage der erarbeiteten ordnungs- und wettbewerbsökonomischen Erkenntnisse wird nach allgemeingültigen Kriterien gesucht, um daraus einen Bewertungsmaßstab für den intersektoralen Vergleich von Liberalisierungsprozessen in verschiedenen Netzindustrien zu entwickeln. Als Arbeitsthese der empirischen Überprüfung im zweiten Teil dient die aus verschiedenen ökonomischen Blickwinkeln gewonnene und theoretisch zu fundierende Vermutung, dass es zur wirksamen Marktöffnung in Netzindustrien einer materiellen Privatisierung sowie einer effektiven und effizienten Marktmachtkontrolle im Bereich des Zugangs zur Netzinfrastruktur bedarf. Anhand dieser These werden die Liberalisierungsprozesse in den Netzsektoren Schienenverkehr, Telekommunikation sowie Energieversorgung in der Bundesrepublik Deutschland aus volkswirtschaftlicher Sicht beurteilt, und es wird auf verbleibenden ordnungspolitischen Reformbedarf hingewiesen. Die theoretischen Ergebnisse sind indes auch auf ähnliche, hier nicht dargestellte Infrastruktursektoren übertragbar.
Inhalt 1 Ziele der Liberalisierung von Netzindustrien:Privatisierung staatlicher Monopole und wettbewerbliche Marktöffnung 2 Markt- und wettbewerbstheoretische Aspekte der Netzinfrastruktur 2.1 Netze als Teil der materiellen Infrastruktur 2.2 Netzinfrastruktur als öffentliches Gut oderInstrument der Daseinsvorsorge? 2.3 Netze als natürliche Monopole? 2.3.1 Nutzenrelevante Netzeffekte 2.3.2 Kostenbestimmende Netzeffekte 2.3.3 Wettbewerbspotenziale trotz Wettbewerbsversagen 3 Wettbewerbsökonomische Implikationen für Netzindustrien 3.1 Vertikale Integration in Netzindustrien 3.1.1 Transaktionskosten versus vertikale Integration 3.1.2 Wettbewerbsökonomische Probleme 3.2 Netzzugangsmodelle 3.3 Institutionelle Ausgestaltung der Wettbewerbsaufsicht 4 Fazit
Inhalt 1 Politikzyklus als konzeptioneller Bezugsrahmen 2 Ökonomische Problematik von Netzindustrien und Liberalisierungsgründe 3 Privatisierung und Marktöffnung als wirtschaftspolitische Aufgaben 4 Politisierung von Liberalisierungsinteressen 4.1 Politiker als Intermediäre 4.2 Zielkonflikte und Interdependenzen mit anderen Politikfeldern 5 Rent-Seeking-Aktivitäten in Netzindustrien 5.1 Der „Markt“ für Rent-Seeking-Aktivitäten 5.2 Der „Wettbewerb“ von Interessengruppen 6 Administrative Umsetzung und Evaluierung von Liberalisierungen 7 Fazit
Inhalt 1 Einführung und Grundlagen 1.1 Problemstellung und Vorgehensweise 1.2 Ordnungsökonomische Systematisierung 1.3 „Neue“ Besonderheitenlehre für Netzindustrien 2 Ansatzpunkte zur Liberalisierung in Netzindustrien 2.1 Liberalisierung durch Privatisierung 2.1.1 Interdependenz von Privatisierung und Marktöffnung 2.1.2 Privatisierungsstufen 2.2 Liberalisierung durch Deregulierung und Re-Regulierung 2.2.1 Abgrenzung des relevanten Marktes: Netzinfrastruktur versus Netzdienstleistungen 2.2.2 Lokalisierung und Kontrolle von Marktmacht bei Netzinfrastruktur 2.3 Modelle zur Gewährleistung eines diskriminierungsfreien Netzzugangs 2.3.1 Verhandelter Netzzugang mit Missbrauchsaufsicht im Sinne der Essential-Facilities-Doktrin 2.3.2 Staatliche Regulierung des Netzzugangs 2.4 Theorie der vertikalen (Des-)Integration 2.4.1 Allokativ-statische, wohlfahrtsökonomische Analyse vertikaler Integration 2.4.2 Institutionenökonomische Analyse vertikaler Integration 2.4.3 Dynamische, wettbewerbsökonomische Analyse vertikaler Integration 2.4.4 Konsequenz: Vertikale Desintegration 3 Institutionelle Ausgestaltung der Wettbewerbsaufsicht 3.1 Systematisierung der Träger und Kompetenzabgrenzung 3.2 Kriterien für eine effiziente Wettbewerbsaufsicht 4 Schlussfolgerungen und intersektoraler Vergleich des Liberalisierungsprozessesin Netzindustrien
Studieneingang optimieren!
(2019)
Einführung in den Band
(2019)
Degradable polymers with a tailorable degradation rate might be promising candidate materials for biomaterial-based cartilage repair. In view of the poor intrinsic healing capability of cartilage, implantation of autologous chondrocytes seeded on a biocompatible slow degrading polymer might be an encouraging approach to improve cartilage repair in the future. This study was undertaken to test if the fiber orientation (random versus aligned) of two different degradable polymers and a polymer intended for long term applications could influence primary articular chondrocytes growth and ultrastructure.
A degradable copoly(ether) esterurethane (PDC) was synthesized via co-condensation of poly(p-dioxanone) diol and poly(epsilon-caprolactone) diol using an aliphatic diisocyanate as linker. Poly(p-dioxanone) (PPDO) was applied as commercially available degradable polymer, while polyetherimide (PEI) was chosen as biomaterial enabling surface functionalization. The fibrous scaffolds of PDC and PPDO were obtained by electrospinning using 1,1,1,3,3,3 hexafluoro-2-propanol (HFP), while for PEI dimethyl acetamide (DMAc) was applied as solvent. Primary porcine articular chondrocytes were seeded at different cell densities on the fibrous polymer scaffolds and analyzed for viability (fluorescein diacetate/ethidiumbromide staining), for type II collagen synthesis (immunolabelling), ultrastructure and orientation on the fibers (SEM: scanning electron microscopy).
Vital chondrocytes adhered on all electrospun scaffolds irrespective of random and aligned topologies. In addition, the chondrocytes produced the cartilage-specific type II collagen on all tested polymer topologies suggesting their differentiated functions. SEM revealed an almost flattened chondrocytes shape on scaffolds with random fiber orientation: whereby chondrocytes growth remained mainly restricted to the scaffold surface. On aligned fibers the chondrocytes exhibited a more spindle-shaped morphology with rougher cell surfaces but only a minority of the cells aligned according to the fibers. As a next step the reduction of the fiber diameter of electrospun scaffolds should be addressed as an important parameter to mimic cartilage ECM structure.
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.
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.
For in vitro studies assessing the interaction of platelets with implant materials, common and standardized protocols for the preparation of platelet rich plasma (PRP) are lacking, which may lead to non-matching results due to the diversity of applied protocols. Particularly, the aging of platelets during prolonged preparation and storage times is discussed to lead to an underestimation of the material thrombogenicity. Here, we study the influence of whole blood-and PRP-storage times on changes in platelet morphology and function.
Whole blood PFA100 closure times increased after stimulation with collagen/ADP and collagen/epinephrine. Twenty four hours after blood collection, both parameters were prolonged pathologically above the upper limit of the reference range. Numbers of circulating platelets, measured in PRP, decreased after four hours, but no longer after twenty four hours. Mean platelet volumes (MPV) and platelet large cell ratios (P-LCR, 12 fL - 40 fL) decreased over time. Immediately after blood collection, no debris or platelet aggregates could be visualized microscopically. After four hours, first debris and very small aggregates occurred. After 24 hours, platelet aggregates and also debris progressively increased. In accordance to this, the CASY system revealed an increase of platelet aggregates (up to 90 mu m diameter)with increasing storage time.
The percentage of CD62P positive platelets and PF4 increased significantly with storage time in resting PRP. When soluble ADP was added to stored PRP samples, the number of activatable platelets decreased significantly over storage time. The present study reveals the importance of a consequent standardization in the preparation of WB and PRP. Platelet morphology and function, particularly platelet reactivity to adherent or soluble agonists in their surrounding milieu, changed rapidly outside the vascular system. This knowledge is of crucial interest, particularly in the field of biomaterial development for cardiovascular applications, and may help to define common standards in the in vitro hemocompatibility testing of biomaterials.
Land use is increasingly recognized as a major driver of biodiversity and ecosystem functioning in many current research projects. In grasslands, land use is often classified by categorical descriptors such as pastures versus meadows or fertilized versus unfertilized sites. However, to account for the quantitative variation of multiple land-use types in heterogeneous landscapes, a quantitative, continuous index of land-use intensity (LUI) is desirable. Here we define such a compound, additive LUI index for managed grasslands including meadows and pastures. The LUI index summarizes the standardized intensity of three components of land use, namely fertilization, mowing, and livestock grazing at each site. We examined the performance of the LUI index to predict selected response variables on up to 150 grassland sites in the Biodiversity Exploratories in three regions in Germany(Alb, Hainich, Schorlheide). We tested the average Ellenberg nitrogen indicator values of the plant community, nitrogen and phosphorus concentration in the aboveground plant biomass, plant-available phosphorus concentration in the top soil, and soil C/N ratio, and the first principle component of these five response variables.
The LUI index significantly predicted the principal component of all five response variables, as well as some of the individual responses. Moreover, vascular plant diversity decreased significantly with LUI in two regions (Alb and Hainich).
Inter-annual changes in management practice were pronounced from 2006 to 2008, particularly due to variation in grazing intensity. This rendered the selection of the appropriate reference year(s) an important decision for analyses of land-use effects, whereas details in the standardization of the index were of minor importance. We also tested several alternative calculations of a LUI index, but all are strongly linearly correlated to the proposed index.
The proposed LUI index reduces the complexity of agricultural practices to a single dimension and may serve as a baseline to test how different groups of organisms and processes respond to land use. In combination with more detailed analyses, this index may help to unravel whether and how land-use intensities, associated disturbance levels or other local or regional influences drive ecological processes.
Incorporating photochromic molecules into organic/inorganic hybrid materials may lead to photoresponsive systems. In such systems, the second-order nonlinear properties can be controlled via external stimulation with light at an appropriate wavelength. By creating photochromic molecular switches containing self-assembled monolayers on Si(111), we can demonstrate efficient reversible switching, which is accompanied by a pronounced modulation of the nonlinear optical (NLO) response of the system. The concept of utilizing functionalized photoswitchable Si surfaces could be a way for the generation of two-dimensional NLO switching materials, which are promising for applications in photonic and optoelectronic devices.
Alles auf Anfang!
(2019)
Im Zuge der Bologna-Reform ist an Hochschulen vieles in Bewegung gekommen. Studium und Lehre sind stärker ins Blickfeld gerückt. Dabei kommt der Studieneingangsphase besondere Bedeutung zu, werden doch hier die Weichen für ein erfolgreiches Studium gestellt. Deshalb ist es verständlich, dass die Hauptanstrengungen der Hochschulen auf den Studieneingang gerichtet sind – ganz nach dem Motto: „Auf den Anfang kommt es an!“. Konsens herrscht dahingehend, dass der Studieneingang neu zu gestalten ist, doch beim „Wie?“ gibt es unterschiedliche Antworten. Zugleich wird immer deutlicher, dass eine wirksame Neugestaltung der Eingangsphase nur mit einer umfassenden Reform des Studiums gelingen kann.
Ziel des vierten Bandes der Potsdamer Beiträge zur Hochschulforschung ist es, eine Zwischenbilanz der Debatte zum Studieneingang zu ziehen. Auf der Basis empirischer Studien werden unterschiedliche Perspektiven auf den Studieneingang eingenommen und Empfehlungen zur Optimierung des Studieneingangs abgeleitet. Die zahlreichen Untersuchungsergebnisse Potsdamer Forschergruppen werden durch weitere nationale sowie internationale Perspektiven ergänzt. Der Band richtet sich an alle, die sich für die Entwicklung an Hochschulen interessieren.
An der Universität Potsdam wurden im Rahmen des Qualitätspakt Lehre-Projekts „Qualität etablieren in Lehre und Lernen (QueLL)“ Maßnahmen für eine Verbesserung der Studienbedingungen und eine Weiterentwicklung der Lehre und des Lernens durchgeführt. Die während der neunjährigen Projektlaufzeit thematisierten Fragestellungen, erarbeiteten Lösungsansätze und entsprechenden Erfahrungen werden im vorliegenden Sammelband in Form von wissenschaftlichen Auseinandersetzungen und Werkstattberichten dargestellt und diskutiert.
Die Beiträge spiegeln in ihrer thematischen Vielfalt unterschiedliche universitäre Übergangsphasen wider, wie in diesem Fall den Übergang in die Hochschule, Übergänge innerhalb der Hochschule (im Kontext der Organisationsentwicklung, der Weiterbildung akademischer Statusgruppen oder der Entwicklung einer digitalen Lehr-Lernkultur) und schließlich den Übergang in die Berufspraxis. Denn während der Projektlaufzeit hat sich gezeigt, dass die Gestaltung von Lehre und Lernen letztlich immer eine Gestaltung solcher Übergänge ist: sowohl zwischen den innerinstitutionellen Ebenen und Bereichen als auch zwischen Akteur/innen der Hochschule und schließlich ebenso innerhalb des Student Life Cycle. Weiterhin wird anhand der Beiträge deutlich, dass die Entwicklung von Lehre und Studium nicht als isolierte Aufgabe verstanden werden kann, sondern in die Strukturen und Prozesse der Universität hineinwirken und Formen der Zusammenarbeit etablieren sollte, die es braucht, um Projekte nachhaltig zu gestalten.
Ziel dieses Bandes ist es, zur Diskussion über Gelingensbedingungen einer nachhaltigen Entwicklung von Lehre und Lernen beizutragen. Damit richtet er sich an Akteur/innen aus der Hochschulleitung, an Lehrende und Forschende sowie Mitarbeitende des Third Space.
Studium nach Bologna
(2017)
Ziel des vorliegenden dritten Bandes der Potsdamer Beiträge zur Hochschulforschung ist es, ausgewählte Aspekte der Hochschuldebatte um Studium und Lehre zu beleuchten und mit empirischen Befunden zu vertiefen. Im Fokus stehen solche aktuellen Debatten wie die Gestaltung des Studieneingangs, die Erhöhung der Beschäftigungsbefähigung, die Qualität der Praktika sowie Probleme der Lehrerbildung. Dabei wird die Hochschuldebatte in Deutschland durch einschlägige Beiträge aus anderen, west- und osteuropäischen Ländern erweitert.
Die Reihe versteht sich als Forum verschiedener Akteure aus der Hochschulforschung, die die Diskussion zur Qualitätsentwicklung in Lehre und Studium mit ihren Impulsen aus Analysen und empirischen Ergebnissen bereichern sollen. Der Band richtet sich an alle, die sich für die Entwicklung an Hochschulen interessieren.
Aim: Assessment of the feasibility and reliability of immune-inflammatory biomarker measurements. Methods: The following biomarkers were assessed in 207 predominantly healthy participants at baseline and after 4 months: MMF, TGF-beta, suPAR and clusterin. Results: Intraclass correlation coefficients (95% CIs) ranged from good for TGF-beta (0.75 [95% CI: 0.33-0.90]) to excellent for MMF (0.81 [95% CI: 0.64-0.90]), clusterin (0.83 [95% CI: 0.78-0.87]) and suPAR (0.91 [95% CI: 0.88-0.93]). Measurement of TGF-beta was challenged by the large number of values below the detection limit. Conclusion: Single measurements of suPAR, clusterin and MMF could serve as feasible and reliable biomarkers of immune-inflammatory pathways in biomedical research.
Purpose UK guidelines recommend dietary saturated fatty acids (SFAs) should not exceed 10% total energy (%TE) for cardiovascular disease prevention, with benefits observed when SFAs are replaced with unsaturated fatty acids (UFAs). This study aimed to assess the efficacy of a dietary exchange model using commercially available foods to replace SFAs with UFAs. Methods Healthy men (n = 109, age 48, SD 11 year) recruited to the Reading, Imperial, Surrey, Saturated fat Cholesterol Intervention-1 (RISSCI-1) study (ClinicalTrials.Gov n degrees NCT03270527) followed two sequential 4-week isoenergetic moderate-fat (34%TE) diets: high-SFA (18%TE SFAs, 16%TE UFAs) and low-SFA (10%TE SFAs, 24%TE UFAs). Dietary intakes were assessed using 4-day weighed diet diaries. Nutrient intakes were analysed using paired t-tests, fasting plasma phospholipid fatty acid (PL-FA) profiles and dietary patterns were analysed using orthogonal partial least square discriminant analyses. Results Participants exchanged 10.2%TE (SD 4.1) SFAs for 9.7%TE (SD 3.9) UFAs between the high and low-SFA diets, reaching target intakes with minimal effect on other nutrients or energy intakes. Analyses of dietary patterns confirmed successful incorporation of recommended foods from commercially available sources (e.g. dairy products, snacks, oils, and fats), without affecting participants' overall dietary intakes. Analyses of plasma PL-FAs indicated good compliance to the dietary intervention and foods of varying SFA content. Conclusions RISSCI-1 dietary exchange model successfully replaced dietary SFAs with UFAs in free-living healthy men using commercially available foods, and without altering their dietary patterns. Further intervention studies are required to confirm utility and feasibility of such food-based dietary fat replacement models at a population level.
IMPORTANCE Inflammatory processes have been suggested to have an important role in colorectal cancer (CRC) etiology. Chemerin is a recently discovered inflammatory biomarker thought to exert chemotactic, adipogenic, and angiogenic functions. However, its potential link with CRC has not been sufficiently explored. OBJECTIVE To evaluate the prospective association of circulating plasma chemerin concentrations with incident CRC. DESIGN, SETTING, AND PARTICIPANTS Prospective case-cohort study based on 27 548 initially healthy participants from the European Prospective Investigation Into Cancer and Nutrition (EPIC)-Potsdam cohort who were followed for up to 16 years. Baseline study information and samples were collected between August 23, 1994, and September 25, 1998. Recruitment was according to random registry sampling from the geographical area of Potsdam, Germany, and surrounding municipalities. The last date of study follow-up was May 10, 2010. Statistical analysis was conducted in 2018. MAIN OUTCOMES AND MEASURES Incident CRC, colon cancer, and rectal cancer. Baseline chemerin plasma concentrations were measured by enzyme-linked immunosorbent assay. CONCLUSIONS AND RELEVANCE This study found that the association between chemerin concentration and the risk of incident CRC was linear and independent of established CRC risk factors. Further studies are warranted to evaluate chemerin as a novel immune-inflammatory agent in colorectal carcinogenesis.
Background: Epidemiological studies suggest that an increased red meat intake is associated with a higher risk of type 2 diabetes, whereas an increased fiber intake is associated with a lower risk. Objectives: We conducted an intervention study to investigate the effects of these nutritional factors on glucose and lipid metabolism, body-fat distribution, and liver fat content in subjects at increased risk of type 2 diabetes. Methods: This prospective, randomized, and controlled dietary intervention study was performed over 6 mo. All groups decreased their daily caloric intake by 400 kcal. The "control" group (N = 40) only had this requirement. The "no red meat" group (N = 48) in addition aimed to avoid the intake of red meat, and the "fiber" group (N = 44) increased intake of fibers to 40 g/d. Anthropometric parameters and frequently sampled oral glucose tolerance tests were performed before and after intervention. Body-fat mass and distribution, liver fat, and liver iron content were assessed by MRI and single voxel proton magnetic resonance spectroscopy. Results: Participants in all groups lost weight (mean 3.3 +/- 0.5 kg, P < 0.0001). Glucose tolerance and insulin sensitivity improved (P < 0.001), and body and visceral fat mass decreased in all groups (P < 0.001). These changes did not differ between groups. Liver fat content decreased significantly (P < 0.001) with no differences between the groups. The decrease in liver fat correlated with the decrease in ferritin during intervention (r(2) = 0.08, P = 0.0021). This association was confirmed in an independent lifestyle intervention study (Tuebingen Lifestyle Intervention Program, N = 229, P = 0.0084). Conclusions: Our data indicate that caloric restriction leads to a marked improvement in glucose metabolism and body-fat composition, including liver-fat content. The marked reduction in liver fat might be mediated via changes in ferritin levels. In the context of caloric restriction, there seems to be no additional beneficial impact of reduced red meat intake and increased fiber intake on the improvement in cardiometabolic risk parameters. This trial was registered at clinicaltrials.gov as NCT03231839.
Predictors and prevalence of hazardous alcohol use in middle-late to late adulthood in Europe
(2022)
Objectives:
Even low to moderate levels of alcohol consumption can have detrimental health consequences, especially in older adults (OA). Although many studies report an increase in the proportion of drinkers among OA, there are regional variations. Therefore, we examined alcohol consumption and the prevalence of hazardous alcohol use (HAU) among men and women aged 50+ years in four European regions and investigated predictors of HAU.
Methods:
We analyzed data of N = 35,042 participants of the European SHARE study. We investigated differences in alcohol consumption (units last week) according to gender, age and EU-region using ANOVAs. Furthermore, logistic regression models were used to examine the effect of income, education, marital status, history of a low-quality parent-child relationship and smoking on HAU, also stratified for gender and EU-region. HAU was operationalized as binge drinking or risky drinking (<12.5 units of 10 ml alcohol/week).
Results:
Overall, past week alcohol consumption was 5.0 units (+/- 7.8), prevalence of HAU was 25.4% within our sample of European adults aged 50+ years. Male gender, younger age and living in Western Europe were linked to both higher alcohol consumption and higher risks of HAU. Income, education, smoking, a low-quality parent-child relationship, living in Northern and especially Eastern Europe were positively associated with HAU. Stratified analyses revealed differences by region and gender.
Conclusions:
HAU was highly prevalent within this European sample of OA. Alcohol consumption and determinants of HAU differed between EU-regions, hinting to a necessity of risk-stratified population-level strategies to prevent HAU and subsequent alcohol use disorders.
Background
Recent research emphasized the role of inflammatory processes in the pathophysiology of depression. Theories hypothesizes that life events (LE) can affect the immune system and trigger depressive symptoms. LE are also considered as one of the best predictors for the onset and course of depressive disorders.
Methods
Observational study across three treatment settings: n=208 depressive patients (75.5%f, M 46.6 y) were examined on depression (BDI-II), life events (ILE) and inflammatory markers (IL-6, CRP, fibrinogen, ICAM-1, TNF-alpha, E-selectin) at baseline (t0), 5-week(t1) and 5-month(t2) follow-up. Effects and interactions were analyzed with regression models.
Results
LE were associated with depressive symptoms at t0 (beta=.209; p=.002) and both follow-ups. Except for CRP, which was linked to depression symptoms at t2 (betai=-.190; p=.032), there were no effects of inflammatory markers on depressive symptoms. At t1, an interaction between CRP and LE in total (beta=-.249; p=.041) was found as well as for LE in the past five years (beta=-.122; p=.027). Similar interactions were found between cumulative LE and ICAM-1 (beta=-.197; p=.003) and IL-6 (beta=-.425; p=.001).
Conclusion
The cumulative burden of LE effects symptoms and treatment outcome in depressive patients. There is some evidence that inflammatory marker may have long-term effects on treatment outcome as they seem to weaken the determining relation between LE and depression.
Purpose: The present work aimed to delineate (i) a revised protocol according to recent methodological developments in evidence generation, to (ii) describe its interpretation, the assessment of the overall certainty of evidence and to (iii) outline an Evidence to Decision framework for deriving an evidence-based guideline on quantitative and qualitative aspects of dietary protein intake. Methods A methodological protocol to systematically investigate the association between dietary protein intake and several health outcomes and for deriving dietary protein intake recommendations for the primary prevention of various non-communicable diseases in the general adult population was developed. Results The developed methodological protocol relies on umbrella reviews including systematic reviews with or without meta-analyses. Systematic literature searches in three databases will be performed for each health-related outcome. The methodological quality of all selected systematic reviews will be evaluated using a modified version of AMSTAR 2, and the outcome-specific certainty of evidence for systematic reviews with or without meta-analysis will be assessed with NutriGrade. The general outline of the Evidence to Decision framework foresees that recommendations in the derived guideline will be given based on the overall certainty of evidence as well as on additional criteria such as sustainability. Conclusion The methodological protocol permits a systematic evaluation of published systematic reviews on dietary protein intake and its association with selected health-related outcomes. An Evidence to Decision framework will be the basis for the overall conclusions and the resulting recommendations for dietary protein intake.