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141.
Patient safety is a new and challenging discipline in the Iranian health care industry. Among the challenges for patient safety improvement, education of medical and paramedical students is intimidating. The present study was designed to assess students’ perceptions of patient safety, and their knowledge and attitudes to patient safety education. This cross-sectional analytical study was conducted in 2012 at Urmia University of Medical Sciences, West Azerbaijan province, Iran. 134 students studying medicine, nursing, and midwifery were recruited through census for the study. A questionnaire was used for collecting data, which were then analyzed through SPSS statistical software (version 16.0), using Chi-square test, Spearman correlation coefficient, F and LSD tests. A total of 121 questionnaires were completed, and 50% of the students demonstrated good knowledge about patient safety. The relationships between students’ attitudes to patient safety and years of study, sex and course were significant (0.003, 0.001 and 0.017, respectively). F and LSD tests indicated that regarding the difference between the mean scores of perceptions of patient safety and attitudes to patient safety education, there was a significant difference among medical and nursing/midwifery students. Little knowledge of students regarding patient safety indicates the inefficiency of informal education to fill the gap; therefore, it is recommended to consider patient safety in the curriculums of all medical and paramedical sciences and formulate better policies for patient safety.  相似文献   
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The most successful active film morphology in organic photovoltaics is the bulk heterojunction (BHJ). The performance of a BHJ arises from a complex interplay of the spatial organization of the segregated donor and acceptor phases and the local order/quality of the respective phases. These critical morphological features develop dynamically during film formation, and it has become common practice to control them by the introduction of processing additives. Here, in situ grazing incidence X‐ray diffraction (GIXD) and grazing incidence small angle X‐ray scattering (GISAXS) studies of the development of order in BHJ films formed from the donor polymer poly(3‐hexylthiophene) and acceptor phenyl‐C61‐butyric acid methyl ester under the influence of two common additives, 1,8‐octanedithiol and 1‐chloronaphthalene, are reported. By comparing optical aggregation to crystallization and using GISAXS to determine the number and nature of phases present during drying, two common mechanisms by which the additives increase P3HT crystallinity are identified. Additives accelerate the appearance of pre‐crystalline nuclei by controlling solvent quality and allow for extended crystal growth by delaying the onset of PCBM‐induced vitrification. The glass transition effects vary system‐to‐system and may be correlated to the number and composition of phases present during drying.  相似文献   
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The aim of this study was to systematically analyze the potential and limitations of using plant functional trait observations from global databases versus in situ data to improve our understanding of vegetation impacts on ecosystem functional properties (EFPs). Using ecosystem photosynthetic capacity as an example, we first provide an objective approach to derive robust EFP estimates from gross primary productivity (GPP) obtained from eddy covariance flux measurements. Second, we investigate the impact of synchronizing EFPs and plant functional traits in time and space to evaluate their relationships, and the extent to which we can benefit from global plant trait databases to explain the variability of ecosystem photosynthetic capacity. Finally, we identify a set of plant functional traits controlling ecosystem photosynthetic capacity at selected sites. Suitable estimates of the ecosystem photosynthetic capacity can be derived from light response curve of GPP responding to radiation (photosynthetically active radiation or absorbed photosynthetically active radiation). Although the effect of climate is minimized in these calculations, the estimates indicate substantial interannual variation of the photosynthetic capacity, even after removing site‐years with confounding factors like disturbance such as fire events. The relationships between foliar nitrogen concentration and ecosystem photosynthetic capacity are tighter when both of the measurements are synchronized in space and time. When using multiple plant traits simultaneously as predictors for ecosystem photosynthetic capacity variation, the combination of leaf carbon to nitrogen ratio with leaf phosphorus content explains the variance of ecosystem photosynthetic capacity best (adjusted R2 = 0.55). Overall, this study provides an objective approach to identify links between leaf level traits and canopy level processes and highlights the relevance of the dynamic nature of ecosystems. Synchronizing measurements of eddy covariance fluxes and plant traits in time and space is shown to be highly relevant to better understand the importance of intra‐ and interspecific trait variation on ecosystem functioning.  相似文献   
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Interstitial cystitis/bladder pain syndrome (IC/BPS) is a debilitating chronic disorder characterized by suprapubic pain and urinary symptoms such as urgency, nocturia, and frequency. The prevalence of IC/BPS is increasing as diagnostic criteria become more comprehensive. Conventional pharmacotherapy against IC/BPS has shown suboptimal effects, and consequently, patients with end-stage IC/BPS are subjected to surgery. The novel treatment strategies should have two main functions, anti-inflammatory action and the regeneration of glycosaminoglycan and urothelium layers. Stem cell therapy has been shown to have dual functions. Mesenchymal stem cells (MSCs) are a promising therapeutic option for IC/BPS, but they come with several shortcomings, such as immune activation and tumorigenicity. MSC-derived extracellular vesicles (MSC-EVs) hold numerous therapeutic cargos and are thus a viable cell-free therapeutic option. In this review, we provide a brief overview of IC/BPS pathophysiology and limitations of the MSC-based therapies. Then we provide a detailed explanation and discussion of therapeutic applications of EVs in IC/BPS as well as the possible mechanisms. We believe our review will give an insight into the strengths and drawbacks of EV-mediated IC/BPS therapy and will provide a basis for further development.  相似文献   
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Genes encoding cellulase enzymes have been investigated in various plants due to the importance of cellulase enzymes in industrial applications, especially in the conversion of biomass into biofuels. Although several cellulase genes have been cloned and characterized, little is known about cellulase genes from garlic or enzyme activities of their gene products. In this study, a cellulase gene from garlic was cloned and characterized in gene and protein levels for the first time. The DNA sequence of the garlic cellulase gene showed 81% identity with the sequence of the endo-beta-1,4-glucanase of Pisum sativum. The open reading frame of this gene is 1,506 bp, which corresponds to 501 deduced amino acids. We identified the novel ORF region, which was translated into a 55.2 kDa protein using the protein expression vector, pET28a, in Escherichia coli and we confirmed that this protein has cellulase activity in vitro. Our study demonstrates that garlic is very useful, not only for the culinary and pharmaceutical industries, but also as an excellent natural source of various kinds of important genes and enzymes.  相似文献   
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