687 research outputs found
Tissue-specific DNase I-hypersensitive sites in the 5´flanking sequences of the trytophane oxygenase and tyrosine aminotransferase genes
The genes for tryptophan oxygenase (TO) and tyrosine aminotransferase (TAT) are expressed in a tissue- and development-specific manner and are regulated by glucocorticoids (TO and TAT) and glucagon or its intracellular mediator cAMP (TAT) in rat liver. We have analyzed the chromatin structure of these genes in the vicinity of the 5' ends with regard to DNaseI hypersensitivity and have found DNaseI hypersensitive sites upstream of each of the promoters. Mapping of this region reveals three closely spaced cleavage sites near the TO promoter and a doublet of sites near the TAT promoter. In both genes additional cleavage sites are found further upstream. All hypersensitive sites of both genes are absent in kidney nuclei and therefore appear to be specific for the tissue expressing the genes. A correlation of expression and modified chromatin structure was also observed in a hepatoma cell line expressing TAT but not TO: hypersensitive sites are present in TAT but not in TO chromatin. Upon glucocorticoid induction an additional hypersensitive site is detected approximately 2 kb upstream of the TAT promoter in liver and hepatoma cells
Das Neue im Alten und das Alte im Neuen - Das Kundenzentrum der Bundesagentur für Arbeit: Die öffentliche Arbeitsvermittlung zwischen inkrementellen und strukturellen Reformen
Das Konzept des neuen Kundenzentrums (KuZ) führt zu einer systematischeren Arbeitsweise und erhöht die Qualität des Service. Um den tief greifenden Umbau der Bundesagentur für Arbeit (BA) zur Dienstleistungsorganisation in dem notwendigen Maße zu befördern, wird die Umsetzung dieses neuen Organisationsmodells allein aber nicht ausreichen. Als problematisch könnte sich zum einen die funktionale Mindestgröße des Kundenzentrums erweisen, die in kleineren Geschäftsstellen schwer gewährleistet werden kann, verschärft noch durch die SGBII- Reform induzierten Personalentzüge. Hier könnte möglicherweise ein Abbau von Arbeitsagentur-Geschäftsstellen drohen. Zum zweiten ist grundsätzlich zu klären, ob die BA in ihrem Reformkonzept eigentlich die richtigen Dienstleistungen an die richtigen Teilklientel (Kunden) adressiert. Gegenwärtig sieht es zum einen so aus, als ob den Arbeitnehmern als auch den Arbeitgebern mit dem meisten Beratungsbedarf weniger Beratung eingeräumt wird. Zum anderen setzt die BA zur Zeit immer noch auf die Idee des ersten Arbeitsmarktdienstleisters als Mengen- statt als Qualitätsgeschäft. Die langfristige Legitimation eines öffentlichen Beschäftigungsdienstes wird hingegen nur zu sichern sein, wenn der Mehrwert seiner Dienstleistungen transparent und nachvollziehbar vermittelt werden kann. -- The new Customer Centre model for German public employment offices leads to more systematic work procedures and increases the quality of services. However, the new organisational model will not be sufficient to transform the Federal Employment Agency (BA) into a modern service organisation. One problem is that the minimum optimal size of the Customer Centre is difficult to guarantee in smaller employment offices. This problem becomes even more acute because the establishment of jobcentres for the long-term unemployed (SGB II reform) has greatly reduced the size of PES agencies. Another problem is whether the BA directs the right services towards the right customers. Currently, it looks as if employees and employers with the most need for counselling services get less services. Moreover, the BA is still more focussed on a quantitative approach rather than on a qualitative approach to labour market services. The long-term legitimacy of a public employment service organisation can only be granted if the value-added of its services is being transparent and understandably communicated.
Framing effects on risk perception of nanotechnology
How do people judge nanotechnology risks that are completely unfamiliar to them? Drawing on results of previous studies on framing and risk perception, two hypotheses about potential influences on nanotechnology risk perception were examined in an experimental study: 1) Risk perception of nanotechnology is influenced by its benefit perception. 2) Risk perception of nanotechnology is influenced by the context in which nanotechnology is embedded, specifically by the characteristics of the enterprises that profit from nanotechnology: large multinational enterprises versus small and medium-sized enterprises. In contrast to findings for other new technologies, e.g. biotechnology, the different types of benefit did not affect risk perceptions in our study. However, we found that characterizing the enterprises as large multinational versus small or medium-sized leads to differences in risk perception. One can speculate that when personal knowledge about a technology is lacking, people use more familiar aspects from the social context as cues for their risk evaluation
The Precautionary Principle and Risk Perception: Experimental Studies in the EMF Area
Possible adverse health effects due to electromagnetic fields (EMFs) from cellular phones and base stations present a major public health issue across Europe. Because scientists cannot exclude that EMFs may cause health problems, the application of the precautionary principle is debated heavily. By considering precautionary measures, political decision makers hope to cope with public fears about EMFs. We present results from two experimental studies that indicate that precautionary measures may trigger concerns, amplify EMF-related risk perceptions, and lower trust in public health protection. Such impacts, questioning common expectations, should be considered in decisions about precautionary measures
Effective spin-wave action for ordered Heisenberg antiferromagnets in a magnetic field
We derive the effective long-wavelength Euclidean action for the
antiferromagnetic spin-waves of ordered quantum antiferromagnets subject to a
uniform magnetic field. We point out that the magnetic field dependence of the
spin-wave dispersion predicted by the usual O(3)-quantum nonlinear sigma model
disagrees with spin-wave theory. We argue that the nonlinear sigma model does
not take into account all relevant spin-wave interactions and derive a modified
effective action for the long-wavelength spin-waves which contains an
additional quartic interaction. At zero temperature the corresponding vertex is
relevant in the renormalization group sense below three dimensions.Comment: 4 pages, 1 eps figure; proceedings of the symposium on "Spin- and
charge-correlations in molecule-based materials", October 2005, Koenigstein
(Taunus), German
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