Studies on the Autoxidation of Phenyl Cycloalkanes

The products of the autoxidation of phenyl cyclopropane ( I ), phenyl cyclobutane ( II ), phenyl cyclopentane ( III ), phenyl cyclohexane ( IV ), phenyl cycloheptane ( V ) and phenyl cyclooctane ( VI ) were analyzed after reduction of the reaction mixtures with LiAlH₄. As products of the attack on the α-C H bonds the corresponding 1-phenyl cycloalkanols and 1-phenyl alkan-1-ols were found. In the case of phenyl cyclopropane some S_R2 ring opening probably takes place. The oxidabilities $ {\rm k}_{\rm p} /\sqrt {{\rm k}_{\rm t}} $, the chain termination constants k_t, the absolute chain propagation constants k_p and the relative chain propagation constant (k_p)_rel were determined for the phenyl cycloalkanes I — VI . As it is to be expected on the basis of the I-strain concept the autoxidation rate of phenyl cyclopentane ( III ) is considerably higher than that of phenyl cyclobutane ( II ) and phenyl cyclohexane ( IV ).     

Chromium(III) compounds as catalysts for Hydrocarbon Oxidation and hydroperoxide decomposition

Chromium stearate and chromium acetylacetonate are very active catalysts both for the oxidation of hydrocarbons by molecular oxygen and for the decomposition of organic hydroperoxides. During these reactions they also catalyze the oxidation of secondary alcohols to the corresponding ketones by organic hydroperoxides. From organic hydroperoxides and chromium(III)compounds chromium (VI) compounds are formed which are probably the effective agents oxidizing secondary alcohols to ketones.     

Distributive and poverty-reducing effects of in-kind housing benefits in Europe: with a case study for Germany

While cash housing benefits are generally included in household disposable income, the effect of social housing is not accounted for. This may provide a misleading picture of the impact of overall housing policies on inequality and poverty, as countries use different policies to help households meet their housing expenses. In this article, we present the first comprehensive study of the impact of in-kind housing benefits on income distribution and poverty in Europe. We contribute to two strands of the literature, notably the one that aims to quantify income advantages derived from housing and the other that aims to incorporate the value of public services in income. For this purpose, we calculate estimates of imputed rent and analyse how these benefits are distributed over the population and how they help to combat poverty. Our estimates are also relevant for the ongoing debate on whether cash or in-kind social transfers are to be preferred in social policy. We illustrate this with a case study for Germany, where we compare the distributive and poverty effect of cash and in-kind social benefits for housing for a longer time period.     

Inulin mixed esters crosslinked with 2-ethyl-hexyl-acrylate and their promotion as bio-based materials

New inulin-based materials were obtained by graft-copolymerization of inulin (poly-β(1 → 2)-fructoside) with 2-ethyl-hexyl acrylate. Inulin mixed esters were first synthesized by acylation using methacryloyl and palmitoyl chlorides. Further, these esters were copolymerized with 2-ethyl-hexyl acrylate in order to obtain bio-based crosslinked materials that could be used as commodity plastics and that would have biodegradable properties. The obtained products were characterized using FT-IR and ¹H NMR spectroscopies, thermogravimetry; differential scanning calorimetry, and activation energy for the degradation processes (using Kissinger method) was calculated. These biomaterials were also subjected to density measurement, tensile and torsion tests to evaluate their mechanical properties.     

Implementation of a virtual correlative light and transmission electron microscope

In the long run, the widespread use of slide scanners by pathologists requires an adaptation of teaching methods in histology and cytology in order to target these new possibilities of image processing and presentation via the internet. Accordingly, we were looking for a tool with the possibility to teach microscopic anatomy, histology, and cytology of tissue samples which would be able to combine image data from light and electron microscopes independently of microscope suppliers. With the example of a section through the villus of jejunum, we describe here how to process image data from light and electron microscopes in order to get one image‐stack which allows a correlation of structures from the microscopic anatomic to the cytological level. With commercially available image‐presentation software that we adapted to our needs, we present here a platform which allows for the presentation of this new but also of older material independently of microscope suppliers. Microsc. Res. Tech. 76:679–686, 2013. © 2013 Wiley Periodicals, Inc.     

In-situ- und On-line-Überwachung und Regelung biotechnologischer Prozesse

In-Situ and On-Line Monitoring and Control of Biotechnological Processes. The advantages of in situ and on-line monitoring of biological production processes are demonstrated by four examples: production of baker's yeast, manufacturing of alkaline protease by B. licheniformis, formation of intracellular fusion protein by recombinant E. coli, and production of antibiotica by ascomycetes and streptomycetes.     

Biphasic modulation of cell proliferation by sulforaphane at physiologically relevant exposure times in a human colon cancer cell line

Sulforaphane (SFN), a cancer chemopreventive compound derived from broccoli, is able to induce cell cycle arrest and apoptosis in various tumor cell lines. Here we show that cell growth inhibition by SFN follows a biphasic pattern: Transient exposure of 40-16 human colon carcinoma cells for up to 6 h resulted in reversible G(2)/M cell cycle arrest and cytostatic growth inhibition even at elevated concentrations, whereas a minimum continuous exposure time of 12 h was necessary for SFN to irreversibly arrest cells in G(2)/M phase and subsequently induce apoptosis. IC(50) values after 12 h of exposure followed by drug-free recovery up to 72 h (6.4-8.1 microM) were indistinguishable from those of chronic exposure for 24 to 72 h (5.4-6.6 microM). Low concentrations of SFN caused a transient decrease in glutathione (GSH) levels followed by GSH induction, which may be related to reversible G(2)/M arrest and cytostatic effects. Depletion of GSH does not seem to play a role in SFN-mediated apoptosis induction. Our data clearly contribute to a better understanding of the kinetics of antiproliferative activity of SFN.