6-Methyl-2-nitro-1-phenyl-hept-4-en-3-ol

In this short note, we report the synthesis of 6-methyl-2-nitro-1-phenyl-hept-4-en-3-ol by a LiAlH4 catalyzed nitroaldol reaction for carbon-carbon bond formation. The title compound was characterized by 1H-NMR, 13C-NMR, MS, IR and elemental analysis

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

Das Fulbright Program in Wien

In der vorliegenden Arbeit werden die verschiedenen Wirkungen des Fulbright Program am wissenschaftlichen Feld in Wien während des Untersuchungszeitraums von 1950 bis 1964 untersucht. Gefragt wird nach den Strategien (Politiken), und anhand der erstmals ausgewerteten Quellen im Archiv der Fulbright Commission können detaillierte Einblicke und Analysen zur Konfiguration des wissenschaftlichen Feldes geleistet werden. Dazu werden drei Bereiche (Konfliktstellen) unterschieden, in denen das Programm mittelbar oder unmittelbar wirksam war. Die erste Konfliktstelle betrifft die Politik der Organisation. Das Fulbright Program setzte hier neue Maßstäbe, indem es eine eigene administrative Einrichtung – die Fulbright Commission in Wien – ins Leben rief und mit einem für damalige Verhältnisse großen Budget ausstattete. Die zweite Konfliktstelle betrifft die Politik des wissenschaftlichen Personals. Der Austausch von WissenschaftlerInnen zwischen den U.S.A. und Österreich war mit einigen Konfrontationen in Wien verbunden – insbesondere die U.S.-amerikanischen Gastprofessoren standen im Mittelpunkt der Debatten und Diskussionen in der Kommission, aber auch in den Professorenkollegien der Fakultät. Die dritte Konfliktstelle betrifft die Politik der wissenschaftlichen Praktiken. Die Entscheidung darüber, was als wissenschaftliche Tätigkeit gelten darf, wurde vom Fulbright Program insofern mitbestimmt, als es eine klare programmatische Schwerpunktsetzung besaß: ‚Social Scientists’ aus den U.S.A. sollten an den Wiener Hochschulen dafür sorgen, dass es zu einem Perspektivenwechsel in der wissenschaftlichen Behandlung von Gesellschaft, Politik und Wirtschaft kam. Dabei kam man zwangsläufig in Konfrontation mit den tradierten Praxisformen vor Ort

Binding of ATP to vascular endothelial growth factor isoform VEGF-A165 is essential for inducing proliferation of human umbilical vein endothelial cells

<p>Abstract</p> <p>Background</p> <p>ATP binding is essential for the bioactivity of several growth factors including nerve growth factor, fibroblast growth factor-2 and brain-derived neurotrophic factor. Vascular endothelial growth factor isoform 165 (VEGF-A₁₆₅) induces the proliferation of human umbilical vein endothelial cells, however a dependence on ATP-binding is currently unknown. The aim of the present study was to determine if ATP binding is essential for the bioactivity of VEGF-A₁₆₅.</p> <p>Results</p> <p>We found evidence that ATP binding toVEGF-A₁₆₅induced a conformational change in the secondary structure of the growth factor. This binding appears to be significant at the biological level, as we found evidence that nanomolar levels of ATP (4-8 nm) are required for the VEGF-A₁₆₅-induced proliferation of human umbilical vein endothelial cells. At these levels, purinergic signaling by ATP <it>via </it>P2 receptors can be excluded. Addition of alkaline phosphate to cell culture lowered the ATP concentration in the cell culture medium to 1.8 nM and inhibited cell proliferation.</p> <p>Conclusions</p> <p>We propose that proliferation of endothelial cells is induced by a VEGF-A₁₆₅-ATP complex, rather than VEGF-A₁₆₅alone.</p

MALDI-TOF High Mass Calibration up to 200 kDa Using Human Recombinant 16 kDa Protein Histidine Phosphatase Aggregates

Background: Protein histidine phosphatase (PHP) is an enzyme which removes phosphate groups from histidine residues. It was described for vertebrates in the year 2002. The recombinant human 16 kDa protein forms multimeric complexes in physiological buffer and in the gas phase. High-mass calibration in matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) has remained a problem due to the lack of suitable standards. Large proteins can hardly be freed of their substructural microheterogeneity by classical purification procedures so that their use as calibrants is limited. A small adduct-forming protein of validated quality is a valuable alternative for that purpose. Methodology/Principal Findings: Three major PHP clusters of ,113, 209 and .600 kDa were observed in gel filtration analysis. Re-chromatography of the monomer peak showed the same cluster distribution. The tendency to associate was detected also in MALDI-TOF MS measuring regular adducts up to 200 kDa. Conclusions/Significance: PHP forms multimers consisting of up to more than 35 protein molecules. In MALDI-TOF MS it generates adduct ions every 16 kDa. The protein can be produced with high quality so that its use as calibration compound for high mass ranges above 100 kDa, where standards are difficult to obtain, is feasible

On the way to the "best childrens´s university": The supply and demand relationship under the principle of partcipation. Opportunities and challenges raised by the children´s university

I know the children’s university is the best university in the world,” says Elisabeth, who is 9 years old and an attendee at the children’s university in Vienna. This charming compliment paid to the children’s university organizers raises an opportunity for further critical inquiries. The statement puts “real” universities on a par with children’s universities and therefore contains the implicit question of the status of children’s universities in the educational landscape: as a hybrid of formal and non-formal education. The specialist conference “On the way to the ‘best Children’s University’: The Supply and Demand Relationship under the Principle of Participation. Opportunities and Challenges”, took place from 8 to 10 May at the University of Cologne, addressed this intermediate position in all its facets. Further topics were possibilities for getting children involved as equal partners, and an international comparison of children’s university models. The conference was funded by the Ford Foundation and supported by KölnAlumni – Freunde und Förderer der Universität e.V. It was organized in partnership with the international children’s university network EUCUNET along with the multinational EU project “SiSCatalyst. Children as change agents for science and society”

MALDI-TOF High Mass Calibration up to 200 kDa Using Human Recombinant 16 kDa Protein Histidine Phosphatase Aggregates

Background: Protein histidine phosphatase (PHP) is an enzyme which removes phosphate groups from histidine residues. It was described for vertebrates in the year 2002. The recombinant human 16 kDa protein forms multimeric complexes in physiological buffer and in the gas phase. High-mass calibration in matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) has remained a problem due to the lack of suitable standards. Large proteins can hardly be freed of their substructural microheterogeneity by classical purification procedures so that their use as calibrants is limited. A small adduct-forming protein of validated quality is a valuable alternative for that purpose. Methodology/Principal Findings: Three major PHP clusters of,113, 209 and.600 kDa were observed in gel filtration analysis. Re-chromatography of the monomer peak showed the same cluster distribution. The tendency to associate was detected also in MALDI-TOF MS measuring regular adducts up to 200 kDa. Conclusions/Significance: PHP forms multimers consisting of up to more than 35 protein molecules. In MALDI-TOF MS it generates adduct ions every 16 kDa. The protein can be produced with high quality so that its use as calibration compoun

Highly Chemoselective Catalytic Photooxidations by Using Solvent as a Sacrificial Electron Acceptor

Catalyst recovery is an integral part of photoredox catalysis. It is often solved by adding another component-a sacrificial agent-whose role is to convert the catalyst back into its original oxidation state. However, an additive may cause a side reaction thus decreasing the selectivity and overall efficiency. Herein, we present a novel approach towards chemoselective photooxidation reactions based on suitable solvent-acetonitrile acting simultaneously as an electron acceptor for catalyst recovery, and on anaerobic conditions. This is allowed by the unique properties of the catalyst, 7,8-dimethoxy-3-methyl-5-phenyl-5-deazaflavinium chloride existing in both strongly oxidizing and reducing forms, whose strength is increased by excitation with visible light. Usefulness of this system is demonstrated in chemoselective dehydrogenations of 4-methoxy- and 4-chlorobenzyl alcohols to aldehydes without over-oxidation to benzoic acids achieving yields up to 70 %. 4-Substituted 1-phenylethanols were oxidized to ketones with yields 80–100 % and, moreover, with yields 31-98 % in the presence of benzylic methyl group, diphenylmethane or thioanisole which are readily oxidized in the presence of oxygen but these were untouched with our system. Mechanistic studies based on UV-Vis spectro-electrochemistry, EPR and time-resolved spectroscopy measurements showed that the process involving an electron release from an excited deazaflavin radical to acetonitrile under formation of solvated electron is crucial for the catalyst recovery

Balancing intestinal and systemic inflammation through cell type-specific expression of the aryl hydrocarbon receptor repressor

As a sensor of polyaromatic chemicals the aryl hydrocarbon receptor (AhR) exerts an important role in immune regulation besides its requirement for xenobiotic metabolism. Transcriptional activation of AhR target genes is counterregulated by the AhR repressor (AhRR) but the exact function of the AhRR in vivo is currently unknown. We here show that the AhRR is predominantly expressed in immune cells of the skin and intestine, different from other AhR target genes. Whereas AhRR antagonizes the anti-inflammatory function of the AhR in the context of systemic endotoxin shock, AhR and AhRR act in concert to dampen intestinal inflammation. Specifically, AhRR contributes to the maintenance of colonic intraepithelial lymphocytes and prevents excessive IL- 1β production and Th17/Tc17 differentiation. In contrast, the AhRR enhances IFN-γ-production by effector T cells in the inflamed gut. Our findings highlight the physiologic importance of cell-type specific balancing of AhR/AhRR expression in response to microbial, nutritional and other environmental stimuli