University of Konstanz

About: University of Konstanz is a education organization based out in Konstanz, Baden-Württemberg, Germany. It is known for research contribution in the topics: Population & Membrane. The organization has 12115 authors who have published 27401 publications receiving 951162 citations. The organization is also known as: University of Constance & Universität Konstanz.

Stress in organizations

Abstract: This chapter summarizes research on stress in organizations. We give an introduction into the concepts of stress, stressors, and stress reactions. We present theories on organizational stress and review evidence from empirical research. Particularly, we focus on observational and longitudinal studies that show that stressors at work have a detrimental effect on health and well-being. We discuss resources such as control at work, social support, coping styles, and self-esteem as potential moderators in the stress process. We describe findings from laboratory and field studies on stress and its effect on performance. We address the question whether stress is related to other organizational variables, including organizational commitment, absenteeism, and turnover. We review research findings on stress interventions and discuss stressor reduction, increase of resource, strain reduction, and life-style change as major stress intervention approaches. We suggest directions for future research for increasing knowledge about stress in organizations. Keywords: health; longitudinal research; performance; resources; stress; stress intervention; well-being

Activation of the 55 kDa TNF receptor is necessary and sufficient for TNF-induced liver failure, hepatocyte apoptosis, and nitrite release.

Abstract: The systemic inflammatory response is characterized by release of circulating TNF which may cause multiorgan failure including septic liver failure. We studied TNF signaling in an appropriate in vitro system with primary murine hepatocyte cultures from normal and genetically altered animals. Either one of the three different TNF species, huTNF-alpha, huTNF-beta, or muTNF-alpha (at concentrations > 1 ng/ml) induced direct hepatocytotoxicity preceded by DNA fragmentation in cells prepared from wild-type C57BL mice. TNF-induced cytotoxicity was preceded by oligonucleosomal DNA fragmentation. Further cellular responses to TNF exposure were induction of nitric oxide synthase and secretion of serum amyloid A. None of the above events occurred in hepatocytes lacking the gene for the 55-kDa TNF receptor (TNF-R1), even after stimulation with > 1 micrograms/ml TNF. However, selective stimulation of the TNF-R1 in wild-type hepatocytes with huTNF-alpha elicited a pattern of responses essentially similar to that seen with muTNF-alpha. We obtained analogous results when we examined the hepatotoxicity of TNF in D-galactosamine-sensitized mice, i.e., DNA fragmentation and liver failure was noted in wild-type mice, whereas TNF-R1-deficient mice were completely resistant. We conclude that the TNF-R1 is not only necessary, but also sufficient for TNF signaling in murine hepatocytes.

Progress, challenges and perspectives in flexible perovskite solar cells

Abstract: Perovskite solar cells have attracted enormous interest since their discovery only a few years ago because they are able to combine the benefits of high efficiency and remarkable ease of processing over large areas. Whereas most of research has been carried out on glass, perovskite deposition and synthesis is carried out at low temperatures (<150 °C) to convert precursors into its final semiconducting form. Thus, developing the technology on flexible substrates can be considered a suitable and exciting arena both from the manufacturing view point (e.g. web processing, low embodied energy manufacturing) and that of the applications (e.g. flexible, lightweight, portable, easy to integrate over both small, large and curved surfaces). Research has been accelerating on flexible PSCs and has achieved notable milestones including PCEs of 15.6% on laboratory cells, the first modules being manufactured, ultralight cells with record power per gram ratios, and even cells made on fibres. Reviewing the literature, it becomes apparent that more work can be carried out in closing the efficiency gap with glass based counterparts especially at the large-area module level and, in particular, investigating and improving the lifetime of these devices which are built on inherently permeable plastic films. Here we review and provide a perspective on the issues pertaining progress in materials, processes, devices, industrialization and costs of flexible perovskite solar cells.

Co-citation analysis and the search for invisible colleges: A methodological evaluation

Abstract: After 30 years of research, co-citation analysis has become the dominant method for the empirical study of the structures of scientific communication. There is a considerable variety of methods and, at the same time, a lack of methodological evaluation. This paper summarizes the present state of co-citation analysis and presents several methods of clustering references. The database used is a selection of 2,114 documents in the field of organization studies from 1986-2000. The evaluative study shows that the choice of methods has a strong impact on the results created. It also shows that the methods of cluster and factor analysis hitherto used have only a limited value in differentiating clearly between schools of scientific research - the 'invisible colleges'.