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21.
The normative data provided in the Wechsler Memory Scale—Revised (WMS—R) manual for individuals aged 25–34 yrs were estimated statistically by interpolation. As an empirical check of this procedure, a representative stratified sample in this age range was selected to match the 1980 US Census data on relevant demographic characteristics. Prorated Full Scale IQs for the group were normally distributed, having a mean of 101.3 (SD?=?14.58, range?=?72–231). Differences between the empirically derived and published index scores appeared to be clinically significant. Substantial intra-individual differences were common when Visual–Verbal or General–Attention/Concentration indexes were compared. Normative data for the WMS—R subtests, indexes, and distribution of differences between indexes is provided. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
22.
Incorporation of cleavable linkers into peptides and proteins is of particular value in the study of biological processes. Here we describe the synthesis of a cleavable linker that is hypersensitive to oxidative cleavage as the result of the periodate reactivity of a vicinal amino alcohol moiety. Two strategies directed towards the synthesis of a building block suitable for solid‐phase peptide synthesis were developed: a chemoenzymatic route, involving L ‐threonine aldolase, and an enantioselective chemical route; these led to α,γ‐diamino‐β‐hydroxybutanoic acids in diastereoisomerically mixed and enantiopure forms, respectively. Incorporation of the 1,2‐amino alcohol linker into the backbone of a peptide generated a conditional peptide that was rapidly cleaved at very low concentrations of sodium periodate. This cleavable peptide ligand was applied in the generation of MHC exchange reagents for the detection of antigen‐specific T cells in peripheral blood cells. The extremely low concentration of periodate required to trigger MHC peptide exchange allowed the co‐oxidation of methionine and disulfide residues to be avoided. Conditional MHC reagents hypersensitive to periodate can now be applied without limitations when UV irradiation is undesired or less practical.  相似文献   
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24.
One-quarter of patients with acute decompensated heart failure (ADHF) experience acute kidney injury (AKI)—an abrupt reduction or loss of kidney function associated with increased long-term mortality. There is a critical need to identify early and real-time markers of AKI in ADHF; however, to date, no protein biomarkers have exhibited sufficient diagnostic or prognostic performance for widespread clinical uptake. We aimed to identify novel protein biomarkers of AKI associated with ADHF by quantifying changes in protein abundance in the kidneys that occur during ADHF development and recovery in an ovine model. Relative quantitative protein profiling was performed using sequential window acquisition of all theoretical fragment ion spectra–mass spectrometry (SWATH–MS) in kidney cortices from control sheep (n = 5), sheep with established rapid-pacing-induced ADHF (n = 8), and sheep after ~4 weeks recovery from ADHF (n = 7). Of the 790 proteins quantified, we identified 17 candidate kidney injury markers in ADHF, 1 potential kidney marker of ADHF recovery, and 2 potential markers of long-term renal impairment (differential abundance between groups of 1.2–2.6-fold, adjusted p < 0.05). Among these 20 candidate protein markers of kidney injury were 6 candidates supported by existing evidence and 14 novel candidates not previously implicated in AKI. Proteins of differential abundance were enriched in pro-inflammatory signalling pathways: glycoprotein VI (activated during ADHF development; adjusted p < 0.01) and acute phase response (repressed during recovery from ADHF; adjusted p < 0.01). New biomarkers for the early detection of AKI in ADHF may help us to evaluate effective treatment strategies to prevent mortality and improve outcomes for patients.  相似文献   
25.
The homogenization and fragmentation of landscapes caused by intensive management is an increasing problem worldwide. Therefore, there is need for development of methods that help to improve sustainable management and maintain the identity of landscapes. We proposed that landscape coherence is the similarity between soil pattern (potential landscape) and land use intensity (actual landscape), which may be investigated by means of correlograms. We studied the spatial autocorrelation (Moran's I) of raster format soil maps and land use maps (1:10,000; 10 m pixel size) in 35 study areas representing all landscape regions in Estonia. Various soil characteristics were taken into consideration in compiling the scale of contrast of 17 soil groups, whereas 19 land use types were ordered according to the intensity of human influence. We use a simple characteristic based on correlograms: a half-value distance lag, hI = 0.5, a distance where Moran's I equals 0.5. According to the value of hI = 0.5, in till-covered areas, the landscape structure is more fragmented in uplands than in lowlands. We found two study areas where the soil pattern was coherent with land use intensity, and detected a tendency that human influence makes the landscape pattern in uplands more homogeneous and in lowlands more heterogeneous, whereas the similarity between landscape patterns in lowlands and uplands is increasing due to human influence. This concept of coherence helps planners and decision makers to determine the optimal land use in landscapes by either reducing or increasing the fragmentation of the landscape pattern.  相似文献   
26.
Ready-to-eat (RTE) foods are processed foodstuffs which have gained popularity in recent times because they can be ingested without further thermic treatments. In this work, the microbiological quality and safety of 90 samples of RTE foods manufactured by small Costa Rican industries was determined to evaluate whether they represent a Public Health risk. Twenty-six samples of pickled vegetables, 18 dips, 18 salads, and 12 sweet treats were studied. Each sample was analyzed with regard to its pH, the presence of culturable microbiological quality indicators and recognized foodborne pathogens (Salmonella, Listeria monocytogenes. Clostridium perfringens, C. botulinum, and Bacillus cereus) Selected genes encoding toxins of C. botulinum and C. perfringens were screened by PCR. Thirty-seven percent of the samples had a level of acidity that could allow the growth and proliferation of bacterial pathogens (pH > or = 4.5). The shelf-life indicators were acceptable but only if the RTE foods are kept at adequate conditions of temperature and humidity. Sixty-four percent of the RTE foods had total coliforms values that evidence inadequate hygiene practices during its elaboration (MPN/g >1000). This result was confirmed by the finding of fecal coliforms in 56% of the samples, which, by the way, are inacceptable for human consumption. All cultures for pathogens were negative, except for 4 samples that contained B. cereus. Toxins of C. botulinum were not detected and one single sample was positive for the PCR for C. perfringens. The elevated degree of fecal contamination detected in the RTE could be prevented by means of good manufacturing practices, better hygiene measures and a deeper attention to critical control points.  相似文献   
27.
The incidence of several respiratory viral infections has been shown to be related to climate. Because humans spend most of their time indoors, measures of indoor climate, rather than outdoor climate, may be better predictors of disease incidence and transmission. Therefore, understanding the relationship between indoor and outdoor climate will help illuminate their influence on the seasonality of diseases caused by respiratory viruses. Indoor-outdoor relationships between temperature and humidity have been documented in temperate regions, but little information is available for tropical regions, where seasonal patterns of respiratory viral diseases differ. We have examined indoor-outdoor correlations of temperature, relative humidity (RH), and absolute humidity (AH) over a 1-year period in each of seven tropical cities. Across all cities, the average monthly indoor temperature was 25 ± 3°C (mean ± standard deviation) with a range of 20–30°C. The average monthly indoor RH was 66 ± 9% with a range of 50–78%, and the average monthly indoor AH was 15 ± 3 g/m3 with a range of 10–23 g/m3. Indoor AH and RH were linearly correlated with outdoor AH when the air conditioning (AC) was off, suggesting that outdoor AH may be a good proxy of indoor humidity in the absence of AC. All indoor measurements were more strongly correlated with outdoor measurements as distance from the equator increased. Such correlations were weaker during the wet season, especially when AC was in operation. These correlations will provide insight for assessing the seasonality of respiratory viral infections using outdoor climate data, which is more widely available than indoor data, even though transmission of these diseases mainly occurs indoors.  相似文献   
28.
 恩斯特马赫研究所(EMI)的弗劳恩霍费尔瞬时动力学研究所通过多功能动态材料试验台、碰撞和冲击装置、冲击管装置进行实验以及数值模拟,从事材料动态特性研究,并将所确定的动态材料数据用于未来新材料的优化设计。  相似文献   
29.
The use of hydrogel in cartilage tissue engineering is especially popular due to its high hydrophilic property which is similar to native cartilage matrix. Alginate hydrogel was used as a transient scaffold material to facilitate chondrocyte proliferation into a three‐dimensional scaffold‐free living hyaline cartilaginous graft (LhCG). As LhCG is purely cell‐based and has a marked resemblance to native hyaline cartilage, it served as an excellent in vitro platform for studying the endochondral ossification pathway. Due to the complexity of events involved throughout endochondral ossification, this study only focuses on early stages of the process where it involves chondrocyte hypertrophy and blood vessel invasion. Human umbilical vein endothelial cells (HUVECs) were selected as the target cells for possible endothelialization in the LhCG template. They were seeded onto the LhCG construct and subjected to vascular endothelial growth factor (VEGF) treatment. Results suggested that VEGF is indeed a potent driving force for initiation of the endochondral pathway. It alone is sufficient to induce hypertrophy in chondrocytes and the corresponding expression of osteogenic genes with or without the presence of HUVECs in the LhCG template. On the other hand, the effect of HUVECs in the LhCG system was less evident. It is hypothesized that this is attributed to the preservation of anti‐angiogenic properties in primary chondrocytes from the LhCG construct, inhibiting HUVECs from endothelialization in the LhCG+HUVEC construct. Based on the outcome from this study, it is recommended that hypertrophy in chondrocytes should be induced prior to endothelial cell introduction so that the microenvironment will be altered to favor angiogenesis within the cartilaginous template. © 2013 Society of Chemical Industry  相似文献   
30.
Hydrogen energy applications often require that systems are used indoors (e.g., industrial trucks for materials handling in a warehouse facility, fuel cells located in a room, or hydrogen stored and distributed from a gas cabinet). It may also be necessary or desirable to locate some hydrogen system components/equipment inside indoor or outdoor enclosures for security or safety reasons, to isolate them from the end-user and the public, or from weather conditions.Using of hydrogen in confined environments requires detailed assessments of hazards and associated risks, including potential risk prevention and mitigation features. The release of hydrogen can potentially lead to the accumulation of hydrogen and the formation of a flammable hydrogen-air mixture, or can result in jet-fires. Within Hyindoor European Project, carried out for the EU Fuel Cells and Hydrogen Joint Undertaking safety design guidelines and engineering tools have been developed to prevent and mitigate hazardous consequences of hydrogen release in confined environments. Three main areas are considered: Hydrogen release conditions and accumulation, vented deflagrations, jet fires and including under-ventilated flame regimes (e.g., extinguishment or oscillating flames and steady burns). Potential RCS recommendations are also identified.  相似文献   
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