Sticking of H_2 on Oxygen-Covered Surface of Vanadium Doped with Oxygen to Various Bulk Concentrations

The sticking probability of Hz on the surface of polycrystalline V covered with oxygen was examined as a function of oxygen concentration in the bulk metal (0.4 to 3.3 at.%) at specimen temperatures from 200 to 1000℃. At all temperatures examined, the sticking probability was strongly dependent on the oxygen concentration in the bulk.Such correlation between the reaction rate of Hz on the surface and the oxygen concentration in the bulk was attributed to the dependence of concentration of oxygen vacancies (holes in surface oxygen coverage) on the oxygen bulk concentration. The values of sticking probability were relatively high even at the oxygen bulk concentration of 3.3 at.%; the oxygen coverage on vanadium was rather "holey" even at the oxygen concentration close to the solubility limit. The activation energy for H_2 dissociation on such holes in the coverage was evaluated to be 10 kJ/mol H_2

Spatiotemporal Expression of MANF in the Developing Rat Brain

Mesencephalic astrocyte-derived neurotrophic factor (MANF) is an evolutionarily conserved neurotrophic factor which exhibited neuroprotective properties. Recent studies suggested that MANF may play a role in the neural development of Drosophila and zebra fishes. In this study, we investigated the spatiotemporal expression of MANF in the brain of postnatal and adult rats. MANF expression appeared wide spread and mainly localized in neurons. In the cerebral cortex, neurons in layer IV and VI displayed particularly strong MANF immunoreactivity. In the hippocampus, intensive MANF expression was observed throughout the subfields of Cornu Amonis (CA1, CA2, and CA3) and the granular layer of the dentate gyrus (DG). In the substantia nigra, high MANF expression was shown in the substantia nigra pars compacta (SNpc). In the thalamus, the anterodorsal thalamic nucleus (ADTN) exhibited the highest MANF immunoreactivity. In the hypothalamus, intensive MANF immunoreactivity was shown in the supraoptic nucleus (SON) and tuberomammillary nucleus (TMN). In the cerebellum, MANF was localized in the external germinal layer (EGL), Purkinje cell layer (PCL), internal granule layer (IGL) and the deep cerebellar nuclei (DCN). We examined the developmental expression of MANF on postnatal day (PD) 3, 5, 7, 9, 15, 21, 30 and adulthood. In general, the levels of MANF were high in the early PDs (PD3 and PD5), and declined gradually as the brain matured; MANF expression in the adult brain was the lowest among all time points examined. However, in some structures, such as PCL, IGL, SON, TMN and locus coeruleus (LC), high expression of MANF sustained throughout the postnatal period and persisted into adulthood. Our results indicated that MANF was developmentally regulated and may play a role in the maturation of the central nervous system (CNS)

A high throughput live transparent animal bioassay to identify non-toxic small molecules or genes that regulate vertebrate fat metabolism for obesity drug development

<p>Abstract</p> <p>Background</p> <p>The alarming rise in the obesity epidemic and growing concern for the pathologic consequences of the metabolic syndrome warrant great need for development of obesity-related pharmacotherapeutics. The search for such therapeutics is severely limited by the slow throughput of animal models of obesity. Amenable to placement into a 96 well plate, zebrafish larvae have emerged as one of the highest throughput vertebrate model organisms for performing small molecule screens. A method for visually identifying non-toxic molecular effectors of fat metabolism using a live transparent vertebrate was developed. Given that increased levels of nicotinamide adenine dinucleotide (NAD) via deletion of CD38 have been shown to prevent high fat diet induced obesity in mice in a SIRT-1 dependent fashion we explored the possibility of directly applying NAD to zebrafish.</p> <p>Methods</p> <p>Zebrafish larvae were incubated with daily refreshing of nile red containing media starting from a developmental stage of equivalent fat content among siblings (3 days post-fertilization, dpf) and continuing with daily refreshing until 7 dpf.</p> <p>Results</p> <p>PPAR activators, beta-adrenergic agonists, SIRT-1 activators, and nicotinic acid treatment all caused predicted changes in fat, cholesterol, and gene expression consistent with a high degree of evolutionary conservation of fat metabolism signal transduction extending from man to zebrafish larvae. All changes in fat content were visually quantifiable in a relative fashion using live zebrafish larvae nile red fluorescence microscopy. Resveratrol treatment caused the greatest and most consistent loss of fat content. The resveratrol tetramer Vaticanol B caused loss of fat equivalent in potency to resveratrol alone. Significantly, the direct administration of NAD decreased fat content in zebrafish. Results from knockdown of a zebrafish G-PCR ortholog previously determined to decrease fat content in <it>C. elegans </it>support that future GPR142 antagonists may be effective non-toxic anti-obesity therapeutics.</p> <p>Conclusion</p> <p>Owing to the apparently high level of evolutionary conservation of signal transduction pathways regulating lipid metabolism, the zebrafish can be useful for identifying non-toxic small molecules or pharmacological target gene products for developing molecular therapeutics for treating clinical obesity. Our results support the promising potential in applying NAD or resveratrol where the underlying target protein likely involves Sirtuin family member proteins. Furthermore data supports future studies focused on determining whether there is a high concentration window for resveratrol that is effective and non-toxic in high fat obesity murine models.</p

Influence of Oxygen and Sulfur on Hydrogen Absorption by Vanadium

Sticking coefficient of H2, α, on a vanadium surface was measured after heat treatments in vacuum at 673, 873, 973 and 1273 K. The values of α were comparable after heat treatments at 673, 873 and 973 K, while significant reduction was observed after heat treatment at 1273 K. Arrhenius plots of α showed that the pre-exponential factor, α0, was far smaller than unity for all heat treatment conditions. This observation indicated that only minor portions of surface sites were active for hydrogen ingress. Change in chemical surface state of V by heat treatments in vacuum at 673, 873, 1073 and 1273 K was also investigated by means of X-ray photoelectron spectroscopy. The specimen surface was mainly covered by VO at 673 K and by an oxygen adlayer at 873 K. Sulfur appeared at 1073 K and completely substituted for oxygen at 1273 K. Namely, sulfur became the dominant surface impurity in the temperature region where α showed significant reduction. It was therefore concluded that the barrier effect of oxygen, including formation of a VO layer, was much weaker than that of sulfur under the present conditions

The Analysis of Results of Monitoring of Biological Communities in Some Lakes

Выполнен анализ динамики первичной продукции планктона, биомассы сообществ зоопланктона и бентоса в оз. Красное (Ленинградская обл.) в период 1964–1984 гг., в Нарочанских озерах (Беларусь) с 1978 по 2010 г., а также в Щучьем заливе Ладожского озера в период его восстановления. Выявлена хорошая связь биомасс сообществ зоопланктона и бентоса с первичной продукцией планктона, рассчитаны соотношения скоростей изменения биомасс гетеротрофов и первичной продукции планктонаThe analysis of dynamics of plankton primary production, biomass of communities of zooplankton and benthos in Lake Krasnoye (Leningrad Oblast) in the period 1964–1984, in Naroch lakes (Belarus) from 1978 to 2010, and in Shchuchiy Bay of Lake Ladoga during the period of its recovery was carried out. Significant relationships between biomass of these communities and plankton primary production were identified; the ratios between the rates of change of heterotroph biomasses and plankton primary production were calculate

The Analysis of Results of Monitoring of Biological Communities in Some Lakes

Выполнен анализ динамики первичной продукции планктона, биомассы сообществ зоопланктона и бентоса в оз. Красное (Ленинградская обл.) в период 1964–1984 гг., в Нарочанских озерах (Беларусь) с 1978 по 2010 г., а также в Щучьем заливе Ладожского озера в период его восстановления. Выявлена хорошая связь биомасс сообществ зоопланктона и бентоса с первичной продукцией планктона, рассчитаны соотношения скоростей изменения биомасс гетеротрофов и первичной продукции планктонаThe analysis of dynamics of plankton primary production, biomass of communities of zooplankton and benthos in Lake Krasnoye (Leningrad Oblast) in the period 1964–1984, in Naroch lakes (Belarus) from 1978 to 2010, and in Shchuchiy Bay of Lake Ladoga during the period of its recovery was carried out. Significant relationships between biomass of these communities and plankton primary production were identified; the ratios between the rates of change of heterotroph biomasses and plankton primary production were calculate

Strength criterion for unidirectional CFRP under off-axis loading

A failure criterion is proposed which allows describing the strength of unidirectional CFRP under tension-compression at an off-axis angle with strength applicable for practical use. An experimental verification was carried out which showed satisfactory agreement with the experimental results. The criterion makes it possible to determine the peak of the failure envelope in the compression area caused, on the one hand, by an increase in strength under in-plane shear due to transverse compressive stresses and, on the other hand, by a decrease in strength due to destruction of the matrix and the interface between unidirectional layer components