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141.
汉语科技词系统是科技词汇知识深层次组织与应用服务工具的集成体系。文章首先概述了词系统的内涵,然后总结了三年来在词汇自动获取、词空间构建和词聚类以及词系统的复杂网络分析评价上所取得的技术突破,并展望了科技词系统下一步的重点研发方向。  相似文献   
142.
苏乔 《科技广场》2011,(4):93-96
项目人力资源管理是项目管理和人力资源管理之间新兴的交叉领域,本文从项目人力资源管理的内涵出发,讨论了我国项目人力资源管理目前所存在的问题,并针对如何正确进行项目人力资源管理提出了一些建议。  相似文献   
143.
This study determines the optimal vascular designs for perfusing engineered tissues. Here, "optimal" describes a geometry that minimizes vascular volume fraction (the fractional volume of a tissue that is occupied by vessels) while maintaining oxygen concentration above a set threshold throughout the tissue. Computational modeling showed that optimal geometries depended on parameters that affected vascular fluid transport and oxygen consumption. Approximate analytical expressions predicted optima that agreed well with the results of modeling. Our results suggest one basis for comparing the effectiveness of designs for microvascular tissue engineering.  相似文献   
144.
We present a microfluidic approach to characterizing temperature-dependent biomolecular interactions. Solvated L-arginine vasopressin (AVP) and its immobilized RNA aptamer (spiegelmer) were allowed to achieve equilibrium binding in a microchip at a series of selected temperatures. Unbound AVP were collected and analyzed with matrix-assisted laser desorption∕ionization mass spectrometry (MALDI-MS), yielding melting curves that reveal highly temperature-dependent zones in which affinity binding (36–45 °C) or dissociation (25–33 °C and 50–65 °C) occurs. Additionally, temperature-dependent binding isotherms were constructed; from these, thermodynamic quantities involved in binding were extracted. The results illustrated a strong change in heat capacity of interaction for this system, suggesting a considerable thermodynamic influence controlling vasopressin-spiegelmer interaction.  相似文献   
145.
Yang H  Qiao X  Bhattacharyya MK  Dong L 《Biomicrofluidics》2011,5(4):44103-4410311
Highly motile Phytophthora sojae (P. sojae) zoospores of an oomycete plant pathogen and antioomycete candidate chemicals were encapsulated into microdroplets. Random fast self-motion of P. sojae zoospores was overcome by choosing an appropriate flow rate for a zoospore suspension. To influence stochastic loading of zoospores into a microfluidic channel, a zoospore suspension was directly preloaded into a microtubing with a largely reduced inner diameter. A relatively high single zoospore encapsulation rate of 60.5% was achieved on a most trivial T-junction droplet generator platform, without involving any specially designed channel geometry. We speculated that spatial reduction in the diameter direction of microtubing added a degree of zoospore ordering in the longitudinal direction of microtubing and thus influenced positively to change the inherent limitation of stochastic encapsulation of zoospores. Comparative phenotypic study of a plant oomycete pathogen at a single zoospore level had not been achieved earlier. Phenotypic changes of zoospores responding to various chemical concentration conditions were measured in multiple droplets in parallel, providing a reliable data set and thus an improved statistic at a low chemical consumption. Since each droplet compartment contained a single zoospore, we were able to track the germinating history of individual zoospores without being interfered by other germinating zoospores, achieving a high spatial resolution. By adapting some existing droplet immobilization and concentration gradient generation techniques, the droplet approach could potentially lead to a medium-to-high throughput, reliable screening assay for chemicals against many other highly motile zoospores of pathogens.  相似文献   
146.
Much research has examined shoulder range of motion adaptations in overhead-unilateral athletes. Based on the void examining overhead-bilateral athletes, especially competitive swimmers, we examined shoulder external rotation, isolated internal rotation, composite internal rotation, and total arc of motion range of motion of competitive swimmers. The range of motion of registered competitive swimmers (n = 144, age = 12-61 years) was compared by limb (dominant, non-dominant), sex, and age group (youth, high school, college, masters). Significantly (P < 0.05) greater dominant external rotation was observed for both men and women high school and college swimmers, youth women swimmers, and men masters swimmers compared with the non-dominant limb. The isolated internal rotation (glenohumeral rotation), composite internal rotation (glenohumeral rotation plus scapulothoracic protraction), and total arc of motion (external rotation plus composite internal rotation) of the non-dominant limb was significantly greater than that of the dominant limb by sex and age group. Youth and high school swimmers demonstrated significantly greater composite internal rotation than college and masters swimmers. Youth swimmers displayed significantly greater total arc of motion than all other age groups. These data will aid in the interpretation of shoulder range of motion values in competitive swimmers during preseason screenings, injury evaluations and post-rehabilitation programmes, with the results suggesting that differences exist in bilateral external rotation, isolated internal rotation, composite internal rotation, and total arc of motion range of motion.  相似文献   
147.
噪声是图像获取、传输和储存过程中不可避免的现象。去噪作为图像处理的首要步骤与基本问题是后续的高层次图像处理的基础。以加性高斯白噪声为例,综述了P-M扩散方程及TV模型的原理,并从视觉与定量指标两个方面比较了去噪效果。最后,在热扩散方程模型预处理条件下比较了两种模型的去噪效果。  相似文献   
148.
Schools are expected to hold an increasingly central role in co-ordinating support for children with mental health needs. However, the role that schools hold in supporting pupils with selective mutism (SM) is complex. Through a Critical Interpretive Synthesis (CIS), this review explores the multidimensional role which educational settings hold in supporting children with SM. Key databases were searched (PsycInfo, British Education Index, Education Resources Information Center, British Library EThOS and Google Scholar) and a conceptual map, informed by experienced practitioners, guided additional purposive searching with a focus on conceptual saturation. A total of twenty-four papers were identified following a further process of appraisal. Reciprocal Translational Analysis (RTA) found that schools hold a tripartite role in supporting children with SM: this incorporated developing a shared understanding of the disorder, engaging in effective (and often multi-professional) planning, and offering direct support through adapting provision and facilitating individual intervention. Through realising this role, schools and educational settings might transform the support currently available for children and young people with SM. Implications for practice, policy and future research also emerged. This included a clear need for enhanced teacher understanding of SM, arguably at the level of initial teacher training (ITT).  相似文献   
149.
通过对台湾高雄餐旅大学与武汉职业技术学院的休闲专业教育比较研究发现,两校的共同点在于均以职业为导向,以培养"应用型、技能型"人才为目标。而台湾高雄餐旅大学休闲与游憩管理专业更加注重学生博雅教育,通识与专业课程科目丰富,实践教学内容务实、形式多样,考评方式多元化,值得大陆高职院校休闲专业借鉴和学习。  相似文献   
150.
研究目的:本研究应用海藻酸钠-壳聚糖微囊保护成骨细胞,接种到β-磷酸三钙/磷酸钙骨水泥(β-TCP/CPC)浆料中,使β-TCP/CPC骨修复材料具有一定的细胞活性,同时提高固化后材料的孔隙率和孔径,以最终实现提高β-TCP/CPC骨水泥的降解速度,加快成骨和骨修复。创新要点:本研究首次应用海藻酸钠-壳聚糖微胶囊包封成骨细胞与CPC浆料复合,复合后实现自动细胞释放,释放出的细胞具有良好的生物学活性。研究方法:(1)高压静电成囊法制备载小鼠成骨前体细胞(MC3T3-E1)的海藻酸钙和海藻酸钠-壳聚糖微胶囊;(2)微囊化MC3T3-E1细胞,进行体外培养,使用细胞计数试剂盒(CCK-8)检测细胞活性,并用钙黄绿素-AM(Calcein-AM)和碘化丙啶(PI)进行活死细胞双重染色;(3)微囊化MC3T3-E1细胞与β-TCP/CPC浆料复合培养后,激光共聚焦扫描显微镜和环境扫描电子显微镜观测细胞在材料上的释放、粘附,CCK-8法检测材料上细胞的活力,碱性磷酸酶(ALP)检测观察细胞的分化状况,茜素红染色观察释放细胞的矿化能力。重要结论:海藻酸钠-壳聚糖微胶囊可作为可注射磷酸钙骨水泥内部接种成骨细胞并实现细胞释放的良好载体,释放出的成骨细胞具有良好的生物学活性。  相似文献   
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