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991.
The capability of 3D printing technologies for direct production of complex 3D structures in a single step has recently attracted an ever increasing interest within the field of microfluidics. Recently, ultrafast lasers have also allowed developing new methods for production of internal microfluidic channels within the bulk of glass and polymer materials by direct internal 3D laser writing. This review critically summarizes the latest advances in the production of microfluidic 3D structures by using 3D printing technologies and direct internal 3D laser writing fabrication methods. Current applications of these rapid prototyped microfluidic platforms in biology will be also discussed. These include imaging of cells and living organisms, electrochemical detection of viruses and neurotransmitters, and studies in drug transport and induced-release of adenosine triphosphate from erythrocytes.  相似文献   
992.
993.
Lay perceptions of collectives (e.g., groups, organizations, countries) implicated in the 2009 H1N1 outbreak were studied. Collectives serve symbolic functions to help laypersons make sense of the uncertainty involved in a disease outbreak. We argue that lay representations are dramatized, featuring characters like heroes, villains and victims. In interviews conducted soon after the outbreak, 47 Swiss respondents discussed the risk posed by H1N1, its origins and effects, and protective measures. Countries were the most frequent collectives mentioned. Poor, underdeveloped countries were depicted as victims, albeit ambivalently, as they were viewed as partly responsible for their own plight. Experts (physicians, researchers) and political and health authorities were depicted as heroes. Two villains emerged: the media (viewed as fear mongering or as a puppet serving powerful interests) and private corporations (e.g., the pharmaceutical industry). Laypersons' framing of disease threat diverges substantially from official perspectives.  相似文献   
994.
995.
The aim of this study was to determine which physiological variables predict excellence in middle- and long-distance runners. Forty middle-distance runners (age 23 ± 4 years, body mass 67.2 ± 5.9 kg, stature 1.80 ± 0.05 m, VO(2max) 65.9 ± 4.5 ml · kg(-1) · min(-1)) and 32 long-distance runners (age 25 ± 4 years, body mass 59.8 ± 5.1 kg, stature 1.73 ± 0.06 m, VO(2max) 71.6 ± 5.0 ml · kg(-1) · min(-1)) competing at international standard performed an incremental running test to exhaustion. Expired gas analysis was performed breath-by-breath and maximum oxygen uptake (VO(2max)) and two ventilatory thresholds (VT(1) and VT(2)) were calculated. Long-distance runners presented a higher VO(2max) than middle-distance runners when expressed relative to body mass (P < 0.001, d = 1.18, 95% CI [0.68, 1.68]). At the intensities corresponding to VT(1) and VT(2), long-distance runners showed higher values for VO(2) expressed relative to body mass or %VO(2max), speed and oxygen cost of running (P < 0.05). When oxygen uptake was adjusted for body mass, differences between groups were consistent. Logistic binary regression analysis showed that VO(2max) (expressed as l · min(-1) and ml · kg(-1) · min(-1)), VO(2VT2) (expressed as ml · kg(-0.94) · min(-1)), and speed at VT(2) (v(VT2)) categorized long-distance runners. In addition, the multivariate model correctly classified 84.7% of the athletes. Thus, VO(2max), VO(2VT2), and v(VT2) discriminate between elite middle-distance and long-distance runners.  相似文献   
996.
The purpose of this qualitative comparative case study was to examine the implementation fidelity of a program designed to deliver the Teaching Personal and Social Responsibility (TPSR) model (Hellison, 2003) through physical education and its relationship with short-term outcomes for elementary school students. The research questions were: (a) was the program implemented with fidelity, and (b) did better fidelity yield better student outcomes. Thus, we conducted a study on the implementation process used by two teachers who delivered the same program in two physical education classes in two different elementary schools in Spain. Data sources included observations and interviews with teachers and nonparticipant observers. Findings indicated that fidelity of implementation in Case 1 was higher and most children in those classes acquired the first three of five TPSR responsibility levels. Implementation fidelity in Case 2 was weaker and achievement of responsibility goals was minimal (only the first of five levels) and less stable for those students. This study is the first to directly examine the connection between TPSR implementation fidelity and student outcomes.  相似文献   
997.
完善电大科研激励机制的若干思考   总被引:1,自引:0,他引:1  
激励机制是现代管理常用的重要方法和手段.在电大的科研管理工作中,建立和完善科学合理的激励机并运用激励机制来激发教职工的科研积极性和创造性,将有效地促进电大科研水平的提高.  相似文献   
998.
The paper investigates how technological change in an industry influence which individuals will identify and exploit entrepreneurial opportunities. We propose that the introduction of new development tools will change knowledge-barriers to entry because they enable the abstraction of specialized knowledge that was previously needed for development. Empirically we test the argument using data from the web design industry in a Nordic country during the period 1992–2003. We compare the education and experience of founders before and after the introduction of web administration tools in 1998 and find a significant difference, which supports the main thesis of our argument.  相似文献   
999.
The paper begins with research studying the concept and nature of Intellectual Capital (IC), as well as how close IC firms are to the stochastic frontier. Then basic concepts of complexity theory – such as agents, self-organized criticality (SOC), connectivities, fractals, and power laws (PLs) – are used to distinguish between two kinds of IC firms’ success: traditional SOC applications to how firms maintain their position in a changing industry vs. how an IC firm (such as Apple) creates a new stochastic frontier. The research sets up PLs as indicators of whether or not firms and industries are SOC-effective and includes propositions about: (1) How IC firms benefit from complexity dynamics and SOC; (2) How PL distributions are indicators of efficacious SOC and adaptivity; and (3) Why IC attributes serve to create more transient dynamics pertaining to the stochastic frontier and the rest of the industry's rank/frequency distribution.  相似文献   
1000.
The primary objective of this paper has been to define a quality university from the user's perspective, based on what students expressed regarding different aspects of the institution. Two methodologically different formats of collecting information have assisted in testing the coherence of their opinions. A qualitative and quantitative approach helped to evaluate the results.  相似文献   
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