Bildungssystem und Zweiter Bildungsweg: Formen und Motive reversibler Bildungsbeteiligung

Die Schulen des Zweiten Bildungswegs (Abendschulen, Kollegs) verzeichneten zwischen den 1950er- und den 1970er-Jahren eine wachsende Nachfrage. Seit Mitte der 1970er-Jahre unterliegt das Wachstum wie auch die Nachfrage selbst Sprüngen und Schwankungen. Langfristig sinkt die Wachstumsrate. Die quantitative Veränderung geht mit einer Veränderung der Rahmenbedingungen einher. Schulen für Erwachsene erfüllen die Funktion der lebenslaufbezogenen Neuzuteilung von Bildungschancen. Diese Funktion der Reversibilisierung steht allerdings heute unter spezifischen Vorzeichen: Die Funktion der nachholenden Eliteförderung ist nicht mehr dominant. Sie hat sich zur allgemeinen Funktion einer nicht nur vom Aufstiegsprinzip geprägten, sondern auch mit der Vermeidung sozialer Exklusion verbundenen Chanceneröffnung im Nachhinein entwickelt. Die Veränderung wird anhand der Literatur zur Entwicklung sowie anhand von Daten zur Teilnehmerstruktur des Zweiten Bildungswegs (ZBW) am Fall des Bundeslandes Hessen aufgezeigt. (DIPF/Orig.)Between the 1950s and 60s, the institutions of adult education experienced a strong increase in demand. Since the mid-1970s, both growth and demand have been subject to leaps and fluctuations. In the long term, the growth rate is sinking. This quantitative change is accompanied by a change in the basic conditions. Schools for adults fulfill the function of a biography-related re-assignment of educational opportunities. Today, however, this function of reversibilization is to be seen under specific circumstances: the function of a retrospective promotion of an elite is no longer dominant; it has developed into a general function of a retrospective opening-up of opportunities not so much determined by the principle of promotion but, rather, by the avoidance of social exclusion. This change is sketched on the basis of literature on this development and of data on the social structure of participation in adult education in the case of the state of Hesse. (DIPF/Orig.

Strategien der Unkrautregulierung in Zuckerrüben - Ergebnisse aus Anbauvergleichen

In 2003 the effect of tillage timing (mouldboard ploughing in autumn or spring) and seeding time on weed density in sugar beet was examined in an on-farm trial near Göttingen. Weed density was highest (110 plants m-2) when sugar beets were sown early (7th April). Ploughing in autumn and late sowing (22nd April) led to the lowest weed density (15 plants m-2). 35 plants m-2 were found after ploughing in spring with late sowing. After early sowing, the weed population was dominated by Matricaria spp., while after late sowing Chenopodium album L. was the dominating species. Besides, late sowing resulted in yield losses compared to early sowing. In 2004 weed density was very low (Ø 15 plants m-2) and neither ploughing time nor harrowing pre- or post-emergence had an effect. This was due to the preceding grass-legume mixture and a very dry spring. Weed population was dominated (80-90 %) by C. album L. and volunteer plants from the preceding crop. Harrowing post emergence tended to reduce sugar beet density but still exceeded 80,000 plants ha-1

A Renormalization Group for Hamiltonians: Numerical Results

We describe a renormalization group transformation that is related to the breakup of golden invariant tori in Hamiltonian systems with two degrees of freedom. This transformation applies to a large class of Hamiltonians, is conceptually simple, and allows for accurate numerical computations. In a numerical implementation, we find a nontrivial fixed point and determine the corresponding critical index and scaling. Our computed values for various universal constants are in good agreement with existing data for area-preserving maps. We also discuss the flow associated with the nontrivial fixed point.Comment: 11 Pages, 2 Figures. For future updates, check ftp://ftp.ma.utexas.edu/pub/papers/koch

A quartz crystal biosensor for measurement in liquids

The detection of anti-human immunodeficiency virus (HIV) antibodies by means of synthetic HIV peptide immobilized on a piezoelectric quartz sensor is demonstrated. The measurement set-up consists of an oscillator circuit, a suitably modified AT-cut thickness-shear-mode quartz crystal with gold electrodes, which is housed in a special reaction vessel, and a computer-controlled frequency counter for the registration of the measured frequency values. The quartz crystal is adapted for a steady operation in liquids at a frequency of 20 MHz. In phosphate-buffered saline solution the oscillator reaches a stability of about 0.5 Hz within a few seconds, of about 2 Hz within 10 min and about 30 Hz within 1 h. The frequency shift due to the adsorption of various proteins to the uncoated sensor surface has been investigated. It can be shown that a stable adsorptive binding of proteins to an oscillating gold surface is feasible and can be used for the immobilization of a receptor layer (e.g. HIV peptide). Specific binding of the anti-HIV monoclonal antibody to the HIV peptide immobilized on the quartz sensor is demonstrated. Control experiments show, however, additional unspecific binding. According to the experiments, the Sauerbrey formula gives a sufficiently accurate value for the decrease of the resonant frequency due to adsorption or binding of macromolecular proteins on the quartz crystal surface

Predominant membrane localization is an essential feature of the bacterial signal recognition particle receptor

<p>Abstract</p> <p>Background</p> <p>The signal recognition particle (SRP) receptor plays a vital role in co-translational protein targeting, because it connects the soluble SRP-ribosome-nascent chain complex (SRP-RNCs) to the membrane bound Sec translocon. The eukaryotic SRP receptor (SR) is a heterodimeric protein complex, consisting of two unrelated GTPases. The SR<it>β </it>subunit is an integral membrane protein, which tethers the SRP-interacting SR<it>α </it>subunit permanently to the endoplasmic reticulum membrane. The prokaryotic SR lacks the SR<it>β </it>subunit and consists of only the SR<it>α </it>homologue FtsY. Strikingly, although FtsY requires membrane contact for functionality, cell fractionation studies have localized FtsY predominantly to the cytosolic fraction of <it>Escherichia coli</it>. So far, the exact function of the soluble SR in <it>E. coli </it>is unknown, but it has been suggested that, in contrast to eukaryotes, the prokaryotic SR might bind SRP-RNCs already in the cytosol and only then initiates membrane targeting.</p> <p>Results</p> <p>In the current study we have determined the contribution of soluble FtsY to co-translational targeting <it>in vitro </it>and have re-analysed the localization of FtsY <it>in vivo </it>by fluorescence microscopy. Our data show that FtsY can bind to SRP-ribosome nascent chains (RNCs) in the absence of membranes. However, these soluble FtsY-SRP-RNC complexes are not efficiently targeted to the membrane. In contrast, we observed effective targeting of SRP-RNCs to membrane-bond FtsY. These data show that soluble FtsY does not contribute significantly to cotranslational targeting in <it>E. coli</it>. In agreement with this observation, our <it>in vivo </it>analyses of FtsY localization in bacterial cells by fluorescence microscopy revealed that the vast majority of FtsY was localized to the inner membrane and that soluble FtsY constituted only a negligible species <it>in vivo</it>.</p> <p>Conclusion</p> <p>The exact function of the SRP receptor (SR) in bacteria has so far been enigmatic. Our data show that the bacterial SR is almost exclusively membrane-bound <it>in vivo</it>, indicating that the presence of a soluble SR is probably an artefact of cell fractionation. Thus, co-translational targeting in bacteria does not involve the formation of a soluble SR-signal recognition particle (SRP)-ribosome nascent chain (RNC) intermediate but requires membrane contact of FtsY for efficient SRP-RNC recruitment.</p

Strategische Partnerschaft zwischen dem Institut für Erziehungswissenschaft der Universität Kassel und Versuchsschulen des Landes Hessen als Impuls für Schulentwicklung und Forschung

In diesem Beitrag wird die strategische Partnerschaft zwischen dem Institut für Erziehungswissenschaft der Universität Kassel und Versuchsschulen des Landes Hessen präsentiert. Dazu werden die Akteure der Zusammenarbeit vorgestellt. Es wird die Form der Zusammenarbeit erläutert und an zwei Forschungsprojekten illustriert. Erkennbar wird, dass durch die unterschiedlichen Formate der Zusammenarbeit Impulse für die Entwicklung von Schulen und für die Gewinnung erziehungswissenschaftlicher Erkenntnisse entstehen. The article presents the strategic partnership between the Institute of Educational Science of the University of Kassel and experimental schools of the state of Hesse. For this purpose, the actors of the cooperation are presented. The form of cooperation is explained and illustrated by two research projects. It becomes apparent that the different formats of cooperation generate impulses for school development and for the acquisition of educational science knowledge

Visualizing fusion of pseudotyped HIV-1 particles in real time by live cell microscopy

RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are.Abstract Background Most retroviruses enter their host cells by fusing the viral envelope with the plasma membrane. Although the protein machinery promoting fusion has been characterized extensively, the dynamics of the process are largely unknown. Results We generated human immunodeficiency virus-1 (HIV-1) particles pseudotyped with the envelope (Env) protein of ecotropic murine leukemia virus eMLV to study retrovirus entry at the plasma membrane using live-cell microscopy. This Env protein mediates highly efficient pH independent fusion at the cell surface and can be functionally tagged with a fluorescent protein. To detect fusion events, double labeled particles carrying one fluorophor in Env and the other in the matrix (MA) domain of Gag were generated and characterized. Fusion events were defined as loss of Env signal after virus-cell contact. Single particle tracking of >20,000 individual traces in two color channels recorded 28 events of color separation, where particles lost the Env protein, with the MA layer remaining stable at least for a short period. Fourty-five events were detected where both colors were lost simultaneously. Importantly, the first type of event was never observed when particles were pseudotyped with a non-fusogenic Env. Conclusion These results reveal rapid retroviral fusion at the plasma membrane and permit studies of the immediate post-fusion events.Published versio

The role of the gut microbiome in the association between habitual anthocyanin intake and visceral abdominal fat in population-level analysis

BACKGROUND: Flavonoid intake modifies the composition of the gut microbiome, which contributes to the metabolism of flavonoids. Few studies have examined the contribution of the gut microbiome to the health benefits associated with flavonoid intake. OBJECTIVES: We aimed to examine associations between habitual intakes of flavonoid subclasses and MRI-determined visceral (VAT) and subcutaneous (SAT) adipose tissue. Uniquely, we also identified associations between the aforementioned measurements and gut microbiome composition sequenced from 16S ribosomal RNA genes. METHODS: We undertook cross-sectional analyses of 618 men and women (n = 368 male), aged 25-83 y, from the PopGen cohort. RESULTS: Higher intake of anthocyanins was associated with lower amounts of VAT [tertile (T)3-T1: -0.49 dm3; β: -8.9%; 95% CI: -16.2%, -1.1%; P = 0.03] and VAT:SAT ratio (T3-T1: -0.04; β: -7.1%; 95% CI: -13.5%, -0.3%; P = 0.03). Higher intakes of anthocyanin-rich foods were also inversely associated with VAT [quantile (Q)4-Q1: -0.39 dm3; β: -9.9%; 95% CI: -17.4%, -1.6%; P = 0.02] and VAT:SAT ratio (Q4-Q1: -0.04; β: -6.5%; 95% CI: -13.3%, -0.9%; P = 0.03). Participants with the highest intakes of anthocyanin-rich foods also had higher microbial diversity (Q4-Q1: β: 0.18; 95% CI: 0.06, 0.31; P < 0.01), higher abundances of Clostridiales (Q4-Q1: β: 449; 95% CI: 96.3, 801; P = 0.04) and Ruminococcaceae (Q4-Q1: β: 313; 95% CI: 33.6, 591; P = 0.04), and lower abundance of Clostridium XIVa (Q4-Q1: β: -41.1; 95% CI: -72.4, -9.8; P = 0.04). Participants with the highest microbial diversity, abundances of Clostridiales and Ruminococcaceae, and lower abundance of Clostridium XIVa had lower amounts of VAT. Up to 18.5% of the association between intake of anthocyanin-rich foods and VAT could be explained by the gut microbiome. CONCLUSIONS: These novel data suggest that higher microbial diversity and abundance of specific taxa in the Clostridiales order may contribute to the association between higher intake of anthocyanins and lower abdominal adipose tissue