The hydrogen evolution and oxidation kinetics during overdischarging of sealed nickel-metal hydride batteries

The hydrogen evolution and oxidation kinetics in NiMH batteries have been investigated under temperature-controlled, steady-state, overdischarging conditions within a temperature range of 10 and 50°C and at discharging currents of 1–330 mA (0.0009 to 0.3 C rate). In situ Raman spectroscopic analyses of the gas phase showed that hydrogen is the only gas evolving inside the battery during overdischarge at the above-mentioned conditions. The pressure increase could be very critical at low temperatures, leading to opening of the safety vent at relatively low discharging currents, for example, only 220 mA at 10°C. The polarization parameters for the hydrogen evolution reaction, such as Tafel slopes and exchange currents were determined at the different temperatures as well as the activation energy for the evolution and oxidation processes. The reaction mechanisms and the rate-determining steps are discussed. These are highly valuable information in NiMH modeling as they are obtained directly from the system of interest. Furthermore, the obtained results make battery simulations more realistic by minimizing the number of parameters involved and making the correct assumptions

Supported Employment and Systems Change: Findings from a National Survey of State Vocational Rehabilitation Agencies

This paper presents findings from a national survey of state Vocational Rehabilitation agencies regarding systems change in supported employment. Respondents from the 50 states and the District of Columbia assessed the impact of state systems change activities and policy implementation efforts on supported employment. Activities perceived to be most important to the implementation and expansion of state supported employment programs were training, technical assistance, capacity building, and policy and funding initiatives. While respondents reported that significant efforts were devoted to conversion during state Title III supported employment system change projects, they reported a lower level of sustained effort following the conclusion of these projects. Respondents from 26 states reported that fiscal incentives exist to provide supported employment services over segregated services. Fiscal disincentives were also reported. Federal and state policies and practices were perceived to influence the administration and operation of state supported employment programs

Evolution of dosage compensation under sexual selection differs between X and Z chromosomes.

Complete sex chromosome dosage compensation has more often been observed in XY than ZW species. In this study, using a population genetic model and the chicken transcriptome, we assess whether sexual conflict can account for this difference. Sexual conflict over expression is inevitable when mutation effects are correlated across the sexes, as compensatory mutations in the heterogametic sex lead to hyperexpression in the homogametic sex. Coupled with stronger selection and greater reproductive variance in males, this results in slower and less complete evolution of Z compared with X dosage compensation. Using expression variance as a measure of selection strength, we find that, as predicted by the model, dosage compensation in the chicken is most pronounced in genes that are under strong selection biased towards females. Our study explains the pattern of weak dosage compensation in ZW systems, and suggests that sexual selection plays a major role in shaping sex chromosome dosage compensation

Effect of Preventive Supplementation with Zinc and other Micronutrients on Non-Malarial Morbidity in Tanzanian Pre-School Children: A Randomized Trial.

The efficacy of preventive zinc supplementation against diarrhea and respiratory illness may depend on simultaneous supplementation with other micronutrients. We aimed to assess the effect of supplementation with zinc and multiple micronutrients on diarrhea and other causes of non-malarial morbidity. Rural Tanzanian children (n = 612) aged 6-60 months and with height-for-age z-score < -1.5 SD were randomized to daily supplementation with zinc (10 mg) alone, multi-nutrients without zinc, multi-nutrients with zinc, or placebo. Children were followed for an average of 45 weeks. During follow-up, we recorded morbidity episodes. We found no evidence that concurrent supplementation with multi-nutrients influenced the magnitude of the effect of zinc on rates of diarrhea, respiratory illness, fever without localizing signs, or other illness (guardian-reported illness with symptoms involving skin, ears, eyes and abscesses, but excluding trauma or burns). Zinc supplementation reduced the hazard rate of diarrhea by 24% (4%-40%). By contrast, multi-nutrients seemed to increase this rate (HR; 95% CI: 1.19; 0.94-1.50), particularly in children with asymptomatic Giardia infection at baseline (2.03; 1.24-3.32). Zinc also protected against episodes of fever without localizing signs (0.75; 0.57-0.96), but we found no evidence that it reduced the overall number of clinic visits. We found no evidence that the efficacy of zinc supplements in reducing diarrhea rates is enhanced by concurrent supplementation with other micronutrients. By reducing rates of fever without localizing signs, supplementation with zinc may reduce inappropriate drug use with anti-malarial medications and antibiotics. ClinicalTrials.gov NCT00623857

Synergistic effects research in the system of complex emulsifier

Вивчено поведінку молекул моно- і диефірів олеїнової кислоти та моно- і диефірів стеаринової кислоти у суміші з поліетиленгліколем-400 на межі поділу фаз олія-вода при виробництві косметичних емульсій. Запропоновано використання 0,5%мас. високодисперсного порошку глауконіту, що концентрується на міжфазній межі з утворенням міцної просторової коагуляційної структури для стійкості дисперсної системи.Изучено поведение молекул моно- и диэфиров олеиновой кислоты и моно- и диэфиров стеариновой кислоты в смеси с полиэтиленгликолем-400 на границе раздела фаз масло-вода при производстве косметических эмульсий. Предложено использование 0,5% масс высокодисперсного порошка глауконита, который концентрируется на межфазной границе с образованием прочной пространственной коагуляционной структуры для стойкости дисперсной системы.It was studied the behavior of molecules mono- and diesters of oleic acid and monoand diesters of stearic acid in a mixture of polyethylene glycol 400 at phase interface of oil-water in the production of cosmetic emulsions. The use of 0,5% by weight. high-dispersive powder of glauconite, which concentrates at interfaces with formation of a strong spatial coagulation structure for stability of dispersed system

Female brain size affects the assessment of male attractiveness during mate choice

Mate choice decisions are central in sexual selection theory aimed to understand how sexual traits evolve and their role in evolutionary diversification. We test the hypothesis that brain size and cognitive ability are important for accurate assessment of partner quality and that variation in brain size and cognitive ability underlies variation in mate choice. We compared sexual preference in guppy female lines selected for divergence in relative brain size, which we have previously shown to have substantial differences in cognitive ability. In a dichotomous choice test, large-brained and wild-type females showed strong preference for males with color traits that predict attractiveness in this species. In contrast, small-brained females showed no preference for males with these traits. In-depth analysis of optomotor response to color cues and gene expression of key opsins in the eye revealed that the observed differences were not due to differences in visual perception of color, indicating that differences in the ability to process indicators of attractiveness are responsible. We thus provide the first experimental support that individual variation in brain size affects mate choice decisions and conclude that differences in cognitive ability may be an important underlying mechanism behind variation in female mate choice

Genotyping of Giardia in Dutch patients and animals: a phylogenetic analysis of human and animal isolates.

Giardia duodenalis (syn. Giardia lamblia, Giardia intestinalis) is a protozoan organism that can infect the intestinal tract of many animal species including mammals. Genetic heterogeneity of G. duodenalis is well described but the zoonotic potential is still not clear. In this study, we analysed 100 Giardia DNA samples directly isolated from human stool specimens, to get more insight in the different G. duodenalis assemblages present in the Dutch human population. Results showed that these human isolates could be divided into two main Assemblages A and B within the G. duodenalis group on the basis of PCR assays specific for the Assemblages A and B and the DNA sequences of 18S ribosomal RNA and the glutamate dehydrogenase (gdh) genes. Genotyping results showed that G. duodenalis isolates originating from Dutch human patients belonged in 35% of the cases to Assemblage A (34/98) and in 65% of the cases to Assemblage B (64/98) whereas two human cases remained negative in all assays tested. In addition, we compared these human samples with animal samples from the Netherlands and human and animal samples from other countries. A phylogenetic analysis was carried out on the DNA sequences obtained from these Giardia and those available in GenBank. Using gdh DNA sequence analysis, human and animal Assemblage A and B Giardia isolates could be identified. However, phylogenetic analysis revealed different sub-clustering for human and animal isolates where host-species-specific assemblages (C, D, E, F and G) could be identified. The geographic origin of the human and animal samples was not a discriminating factor

The Structure of Ca2+ Sensor Case16 Reveals the Mechanism of Reaction to Low Ca2+ Concentrations

Here we report the first crystal structure of a high-contrast genetically encoded circularly permuted green fluorescent protein (cpGFP)-based Ca2+ sensor, Case16, in the presence of a low Ca2+ concentration. The structure reveals the positioning of the chromophore within Case16 at the first stage of the Ca2+-dependent response when only two out of four Ca2+-binding pockets of calmodulin (CaM) are occupied with Ca2+ ions. In such a “half Ca2+-bound state”, Case16 is characterized by an incomplete interaction between its CaM-/M13-domains. We also report the crystal structure of the related Ca2+ sensor Case12 at saturating Ca2+ concentration. Based on this structure, we postulate that cpGFP-based Ca2+ sensors can form non-functional homodimers where the CaM-domain of one sensor molecule binds symmetrically to the M13-peptide of the partner sensor molecule. Case12 and Case16 behavior upon addition of high concentrations of free CaM or M13-peptide reveals that the latter effectively blocks the fluorescent response of the sensor. We speculate that the demonstrated intermolecular interaction with endogenous substrates and homodimerization can impede proper functioning of this type of Ca2+ sensors in living cells