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Local communities with good stocks of social capital nurture and support the families residing within. This qualitative study explored through the perspectives of mothers, how families with children aged 0–5 years build social capital in newer residential areas in Perth, Western Australia. Parenthood generally increased the desire to connect to one's local community, which activated and enhanced social capital. Two themes appear to drive this desire: an increased need for social support and an increased vested interest in the local community. However, newer residential areas commonly have a lag of community infrastructure needed to provide opportunities for families with young children to interact with other families. Urban planning and community sectors need to coordinate to provide infrastructure and opportunities for families with young children to connect and build social capital within their local communities.  相似文献   
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Glutamate racemases (GR) are members of the family of bacterial enzymes known as cofactor-independent racemases and epimerases and catalyze the stereoinversion of glutamate. D-amino acids are universally important for the proper construction of viable bacterial cell walls, and thus have been repeatedly validated as attractive targets for novel antimicrobial drug design. Significant aspects of the mechanism of this challenging stereoinversion remain unknown. The current study employs a combination of MD and QM/MM computational approaches to show that the GR from H. pylori must proceed via a pre-activation step, which is dependent on the enzyme's flexibility. This mechanism is starkly different from previously proposed mechanisms. These findings have immediate pharmaceutical relevance, as the H. pylori GR enzyme is a very attractive allosteric drug target. The results presented in this study offer a distinctly novel understanding of how AstraZeneca's lead series of inhibitors cripple the H. pylori GR's native motions, via prevention of this critical chemical pre-activation step. Our experimental studies, using SPR, fluorescence and NMR WaterLOGSY, show that H. pylori GR is not inhibited by the uncompetitive mechanism originally put forward by Lundqvist et al.. The current study supports a deep connection between native enzyme motions and chemical reactivity, which has strong relevance to the field of allosteric drug discovery.  相似文献   
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Background  

Consumption of healthy diets that contribute with adequate amounts of fat and fatty acids is needed for children. Among Guatemalan children, there is little information about fat intakes. Therefore, the present study sought to assess intakes of dietary fats and examine food sources of those fats in Guatemalan children.  相似文献   
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The organizational aspects of user‐centered software development in a financial services company are presented. The financial services industry sector is one of the industrial sectors to embark on the development of computer software as a consumer product. The nature of business in the service sector predisposes it to encounter difficulties in developing software aimed at meeting customer demands. Lack of familiarity and experience with the product design and implementation processes, as well as reliance on usability for acceptance, are major obstacles encountered. Difficulties, insights, and lessons learned regarding organizational ergonomics issues faced by a user‐centered design group are provided, and a hybrid resource distribution model is proposed to guide other service sector companies in their future software development efforts. © 2007 Wiley Periodicals, Inc. Hum Factors Man 17: 245–262, 2007.  相似文献   
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Colleen E. Rostad 《Fuel》2010,89(5):997-2150
Solvent dyes are used to color refined petroleum products to enable differentiation between gasoline, diesel, and jet fuels. Analysis for these dyes in the hydrocarbon product is difficult due to their very low concentrations in such a complex matrix. Flow injection analysis/electrospray ionization/mass spectrometry in both negative and positive mode was used to optimize ionization of ten typical solvent dyes. Samples of hydrocarbon product were analyzed under similar conditions. Positive electrospray ionization produced very complex spectra, which were not suitably specific for targeting only the dyes. Negative electrospray ionization produced simple spectra because aliphatic and aromatic moieties were not ionized. This enabled screening for a target dye in samples of hydrocarbon product from a spill.  相似文献   
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Both theory and subject matter experts were used to generate items for a survey designed to increase understanding of why psychologists join, remain in, or leave the Canadian Psychological Association (CPA). The subject matter experts included current, former, and nonmember psychologists. 2,200 questionnaires were distributed by e-mail, and 275 were sent by surface mail. The response rates were 20% and 29% for e-mail and surface mail, respectively. Principal components analysis of the survey items resulted in 5 factors: outcomes, advocacy, organizational justice, annual convention, and professional recognition. Discriminant function analysis results showed that, on the basis of these factors, the authors were able to correctly classify respondents as current vs former members, and current vs never been members. Current members, former members, and psychologists who never joined CPA were found to differ significantly on their rating of most factors. The factors relevant for retaining members differ from those that attract psychologists to join CPA. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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The authors propose that the costs and benefits of directed forgetting in the list method result from an internal context change that occurs between the presentations of 2 lists in response to a "forget" instruction. In Experiment 1 of this study, costs and benefits akin to those found in directed forgetting were obtained in the absence of a forget instruction by a direct manipulation of cognitive context change. Experiment 2 of this study replicated those findings using a different cognitive context manipulation and investigated the effects of context reinstatement at the time of recall. Context reinstatement reduced the memorial costs and benefits of context change in the condition where context had been manipulated and in the standard forget condition. The results are consistent with a context change account of directed forgetting. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Current wrought magnesium alloys: Strengths and weaknesses   总被引:9,自引:0,他引:9  
The opportunities for extruded and sheet magnesium products in the automotive industry, in particular, are increasing as the quest for lightweighting gains momentum. However, the current alloys all have limitations and these are accentuated when higher productivity targets are also imposed. This article attempts to summarize the strengths and weaknesses of the current wrought alloys, with particular emphasis on the extrusion process, and also considers alternative processing routes which may be useful in overcoming some of these shortcomings. For more information, contact Colleen Bettles, CMIT Private Bag 33, Clayton South MDC, Clayton Victoria 3169, Australia; +61-3-95452936; fax +61-3-95441128; e-mail Colleen.Bettles@csiro.au.  相似文献   
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