Compulsory education - in schools only? : divergent developments in Germany

Germany is the focus of this paper, owing to the fact that since 1938 it has had the strictest laws on compulsory schooling worldwide. As a result, homeschooling in Germany has become virtually impossible. There are interesting divergences between policy and practice in the German setting, both in the country’s educational history and present educational problems. The Länder (federal states) have the responsibility for education, and they are taking a much stricter line against homeschoolers than a decade ago, especially by depriving parents of the custody of their homeschooled children at an early stage. The laws relied upon, however, were never intended to deal with such educational matters; they were designed to punish parents who abuse or neglect their children. The present, highly questionable legal action succeeds only because of the consent of state schools, state social welfare offices, and courts. The same laws are not used against the parents of the approximately 250,000 teens who are truant. The functioning of the legal and sociological machinery in Germany is being employed aggressively to stamp out homeschooling, while at the same time it ignores the crucial issue of parents who allow their children to skip school—thus depriving them of an adequate education at home or elsewhere. At the same time, the number of specialists in law and education, as well as politicians and governmental experts who argue in favor of homeschooling is growing, and media reports on homeschooling are much more positive than they were a decade ago

q-deformed superconformal algebra on quantum superspace

A quantum deformation of 4-dimensional superconformal algebra realized on quantum superspace is investigated. We study the differential calculus and the action of the quantum generators corresponding to $sl_q(1|4)$ which act on the quantum superspace. We derive deformed $su(1|2,2)$ algebras from the deformed $sl(1|4)$ algebra. Through a contraction procedure we obtain a deformed super-Poincar{\'e} algebra.Comment: 11 pages, KUCP-56, LaTeX fil

Integration of a virus membrane protein into the lipid bilayer of target cells as a prerequisite for immune cytolysis

Structural requirements for membrane antigens on target cells to mediate immune cytolysis were studied in a model system with purified membrane proteins from Semliki Forest virus (SFV). These SFV spike proteins were isolated in the form of detergent- and lipid-free protein micelles (29S complexes) or, after reconstitution into lipid vesicles, in the form of virosomes. Both the 29S complexes and the virosomes were found to bind well to murine tumor cells (P815 or Eb). When these cells, however, were used as target cells in complement-dependent lysis or in antibody-dependent cell- mediated cytotoxicity assays in the presence of anti-SFV serum, they were not lysed, although they effectively bound the antibody and consumed complement. The same tumor cells infected with SFV served as positive controls in both assays. Different results were obtained when inactivated Sendai virus was added as a fusion reagent to the cells coated with either virosomes or 29S complexes. Under these conditions the virosome-coated cells became susceptible to SFV- specific lysis, whereas the 29S complex-coated cells remained resistant. Evidence that the susceptibility to lysis ofvirosome-coated cells was dependent on active fusion and, therefore, integration of the viral antigens into the lipid bilayer of the target cells was derived from control experiments with enzyme-treated Sendai virus preparations. The 29S complexes and the virosomes partially and selectively blocked the target cell lysis by anti-H-2 sera but not by anti-non-H-2 sera confirming our previous finding that major histocompatibility antigens serve as receptors for SFV. The general significance of these findings for mechanisms of immune cytolysis is dicussed

A Transferable Infochemical for Multiple Crustaceans and Mechanistic Assessment of its pH Dependency

Many organisms rely on their sense of smell to explore and interact with their environment. Meeting another organism, infochemicals help them decide whether to eat it, flee, fight or mate with it. The infochemical 2-phenylethylamine (PEA) has previously been associated with predator avoidance in mammals and feeding deterrence in algae. This thesis explores the hypothesis that PEA also induces a comparable avoidance behaviour in crustaceans. In behaviour assays with shore crabs and hermit crabs, movement patterns and behavioural displays were explored in current average marine pH conditions and end-of-the-century average pH, as associated with climate change. Furthermore, using liquid chromatography with tandem mass-spectrometry, shore crab urine was analysed for PEA. Results indicate that PEA attracts both species in reduced pH conditions, rather than deterring them as expected for a predator cue. Agonistic displays in response to PEA and evidence for PEA in shore crab urine suggest that PEA mediates agonistic interactions in crustaceans. Excreted with urine, PEA elicits the full behavioural response in crustaceans only in decreased pH conditions. Therefore, this thesis tested the hypothesis that the pH-dependent response hinges on pH-dependent changes to the infochemical itself. Quantum chemical computations validated by nuclear magnetic resonance (NMR) spectroscopy allowed calculating PEA's different protonation states, and its interaction with a model receptor in different protonation states. Results confirm that the pH-dependent response to PEA could be attributed to changes in charge distribution in the infochemical, potentially leading to altered receptor-ligand affinity. A comparison with the neurotransmitter dopamine reveals that the exact chemical structure and charge distribution of PEA matters for its biological function. Although dopamine and PEA are broadly chemically similar, their biological role for crustaceans appears different. In summary, PEA is an infochemical mediating agonistic interactions in crustaceans in a pH-dependent manner

IMMUNE RESPONSES AGAINST NATIVE AND CHEMICALLY MODIFIED ALBUMINS IN MICE : I. ANALYSIS OF NON-THYMUS-PROCESSED (B) AND THYMUS-PROCESSED (T) CELL RESPONSES AGAINST METHYLATED BOVINE SERUM ALBUMIN

Immune cells induced by bovine serum albumin (BSA) and its methylated derivative (MBSA) have been compared in a cooperative cell transfer system for their content of BSA-specific antibody-forming cell precursors (AFCP, B) and BSA-specific helper (T) cells. When MBSA immune cells were transferred together with hapten-primed cells into recipient mice which were stimulated by a hapten-BSA conjugate, their cooperative secondary anti-hapten response was as good as in case of transferred BSA immune cells. Their secondary anti-BSA response, however, was markedly reduced (reduction factor > 30). Hapten-MBSA conjugates had the same capacity to react with BSA-specific helper cells in the cooperative secondary anti-hapten response as hapten-BSA conjugates but had a reduced ability to react with BSA-specific AFCP cells. In spite of the pronounced reduction of the B cell response, MBSA had the same threshold dose as BSA for activating BSA-specific T cells. These data suggest that B and T cells recognize different epitopes on the BSA molecule, only those recognized by B cells being affected by the methylation procedure

Agility in Information Systems – A Literature Review on Terms and Definitions

Agility is a term used in many works in the context of information systems. When studying the concept closer, it became obvious that there is a terminological heterogeneity preventing a common definition whilst at the same time not preventing the frequent use of the term. In order to approach the term in a structured way, the following two paths were chosen. Firstly, the term was traced back to its roots which showed its first appearance in organisational theory. Secondly, the major IS conferences (ECIS and ICIS) and the requirements engineering conference as a major computer science conference were analysed from 2001 when the agile manifesto was published which led to a wave of works on agility. The descriptive results are presented in the paper