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排序方式: 共有193条查询结果,搜索用时 31 毫秒
71.
昆明城市空间结构发展的句法研究 总被引:2,自引:0,他引:2
利用空间句法轴线地图模型的整体集成度、局部集成度、可理解度三个关键参数,分别对昆明不同年代现状图和总体规划图进行定量分析,得出空间句法能够动态地体现空间结构演化过程、敏感地把握空间结构转变时刻、准确地预测城市发展方向及完整地呈现城市内部结构变迁的结论。通过与总体规划确定的规划重点和空间结构对比,句法分析能够找出1982年昆明空间规划存在违背发展趋势、1996年空间规划丧失昆明结构调整时机的问题,体现了空间句法在城市空间结构演变中显著的应用价值。根据空间句法对昆明城市空间结构发展的分析,对未来城市空间结构优化提出加强区域协调发展、推行多中心建设、体现历史文化名城特色和完善慢行交通体系的规划策略,引导城市空间结构可持续发展。 相似文献
72.
Production and functional characterisation of antioxidative hydrolysates from corn protein via enzymatic hydrolysis and ultrafiltration 总被引:6,自引:0,他引:6
Corn protein was hydrolysed by three microbial proteases and further separated by sequential ultra-filtration to 12 hydrolysate fractions which were investigated for free radical scavenging capacity and chelating activity. The oxygen radical absorbance capacity (ORAC) of the hydrolysates varied significantly between 65.6 and 191.4μmoles Trolox equivalents (TE)/g dried weight with a small peptide fraction (NP-F3) produced by neutral protease (NP) possessing the highest antioxidant activity. The 1,1-diphenyl-2-picrylhydrazyl radical (DPPH()) scavenging activities of the hydrolysate fractions also varied significantly between 18.4 and 38.7μmoles TE/g. Two fractions (AP-F2 and AP-F3) produced by alkaline protease (AP) showed the strongest activity. However, no significant difference was detected on the chelating activity of the fractions. NP-F3, AP-F2, and AP-F3 were incorporated into ground beef to determine their effects on lipid oxidation during 15-day storage period. NP-F3 was the only fraction that inhibited lipid oxidation at both 250 and 500μg/g levels by as much as 52.9%. 相似文献
73.
Carina Levin Ariel Koren Annie Rebibo-Sabbah Maya Levin Naama Koifman Benjamin Brenner Anat Aharon 《International journal of molecular sciences》2021,22(18)
Beta thalassemia major (βT) is a hereditary anemia characterized by transfusion-dependency, lifelong requirement of chelation, and organ dysfunction. MicroRNA (miRNA) can be packed into extracellular vesicles (EVs) that carry them to target cells. We explored EV-miRNA in βT and their pathophysiologic role. Circulating EVs were isolated from 35 βT-patients and 15 controls. EV miRNA was evaluated by nano-string technology and real-time quantitative polymerase chain reaction (RT-qPCR). We explored effects of EVs on cell culture proliferation, apoptosis, and signal transduction. Higher amounts of small EV (exosomes) were found in patients than in controls. The expression of 21 miRNA was > two-fold higher, and of 17 miRNA < three-fold lower in βT-EVs than control-EVs. RT-qPCR confirmed differential expression of six miRNAs in βT, particularly miR-144-3p, a regulator of erythropoiesis. Exposure of endothelial, liver Huh7, and pancreatic 1.1B4 cells to βT-EVs significantly reduced cell viability and increased cell apoptosis. βT-EV-induced endothelial cell apoptosis involved the MAPK/JNK signal-transduction pathway. In contrast, splenectomized βT-EVs induced proliferation of bone marrow mesenchymal stem cells (BM-MSC). In summary, the miR-144-3p was strongly increased; βT-EVs induced apoptosis and decreased endothelial, pancreatic, and liver cell survival while supporting BM-MSC proliferation. These mechanisms may contribute to βT organ dysfunction and complications. 相似文献
74.
Cover Picture: A Recombinant Collagen–mRNA Platform for Controllable Protein Synthesis (ChemBioChem 10/2015)
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75.
Interactions between 1,319 sales clerks and customers were observed. Clerk emotional behavior (Rafaeli & Sutton, 1987), clerk sex, wearing a smock and a name tag, the presence of other clerks or other customers, and customer sex were coded. As predicted, female clerks displayed positive emotions more frequently than male clerks, suggesting that sex role socialization may generalize to behavior at work. Male clients, however, received more positive emotional expressions than female clients, suggesting that individuals of both genders attribute higher status to men. Clerks were more likely to display positive emotions when wearing a uniform, suggesting that an organizational identifier such as a smock or name tag may increase an employee's self-awareness. Consistent with Sutton & Rafaeli (1987), clerks were less likely to display positive emotions if a line of customers or a coworker was present. No relationship was observed between work shift (time of day) and the display of positive emotions. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
76.
This paper constructs a contextual space for plotting the positions of P and D (Planning and design) methods, thus offering a framework for analysing, comparing and contrasting P and D approaches. Three dimensions make up this space: strategy, people involvement and attitude toward change. The strategy continuum varies between the extreme ends: pure inquiry and pure will. The people involvement dimension describes the passage of design control from designer to client. The scale for change attitude spans the distance between aversion to change and exploitation of change. Several well-known P and D methods and approaches are discussed and plotted, to test the validity of the suggested framework. 相似文献
77.
It is pointed out that the above-titled paper by F.X. Canning (ibid., vol.39, no.11, p.1545-52, Nov. 1991) neglects an earlier paper by the commenter (ibid., vol.37, no.12, p.1559-65, Dec. 1989) which describes the determination of the resonances of integral equation operators. The commenter suggests that the method used by Canning for correcting scattered fields is incorrect or impractical since it is based on an integral equation that is ill posed. Canning responds by showing that the matrix problem one must solve is not ill posed, and that the objections raised by Marks stem from failing to properly distinguish the properties of the matrix from the properties of the integral equation. Responses are also given to several specific statements made in the above comments 相似文献
78.
Reports on the combined individual and family therapy of a 17-yr-old survivor of incest following the incarceration of her father and her removal from home. After 1 yr of individual therapy, family therapy was initiated including the perpetrator-father who was released from jail for the sessions. The aims of therapy included protecting the integrity of the family and reinstating the victim's position in the family if possible. Therapeutic tools which were most relevant in promoting these changes are detailed with specific emphasis on an innovative use of video which served both to protect the youngster, reempower her, and reengage the family with her. The dilemma of voluntary vs legally mandated therapy in the management of resistance is closely examined. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
79.
How do people judge the monetary value of objects? One clue is provided by the typical endowment study (D. Kahneman, J. L. Knetsch, & R. H. Thaler, 1991), in which participants are randomly given either a good, such as a coffee mug, that they may later sell ("sellers") or a choice between the good and amounts of cash ("choosers"). Sellers typically demand at least twice as much as choosers, inconsistent with economic theory. This result is usually explained by an increased weighting of losses, or loss aversion. The authors provide a memory-based account of endowment, suggesting that people construct values by posing a series of queries whose order differs for sellers and choosers. Because of output interference, these queries retrieve different aspects of the object and the medium of exchange, producing different valuations. The authors show that the content and structure of the recalled aspects differ for selling and choosing and that these aspects predict valuations. Merely altering the order in which queries are posed can eliminate the endowment effect, and changing the order of queries can produce endowment-like effects without ownership. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
80.
A validation study of the Keyboard Personal Computer Style instrument (K-PeCS) for use with children
This study examines a potential instrument for measurement of typing postures of children. This paper describes inter-rater, test-retest reliability and concurrent validity of the Keyboard Personal Computer Style instrument (K-PeCS), an observational measurement of postures and movements during keyboarding, for use with children. Two trained raters independently rated videos of 24 children (aged 7-10 years). Six children returned one week later for identifying test-retest reliability. Concurrent validity was assessed by comparing ratings obtained using the K-PECS to scores from a 3D motion analysis system. Inter-rater reliability was moderate to high for 12 out of 16 items (Kappa: 0.46 to 1.00; correlation coefficients: 0.77-0.95) and test-retest reliability varied across items (Kappa: 0.25 to 0.67; correlation coefficients: r = 0.20 to r = 0.95). Concurrent validity compared favourably across arm pathlength, wrist extension and ulnar deviation. In light of the limitations of other tools the K-PeCS offers a fairly affordable, reliable and valid instrument to address the gap for measurement of typing styles of children, despite the shortcomings of some items. However further research is required to refine the instrument for use in evaluating typing among children. 相似文献