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251.
This article presents an overview of open access publishing and open access archiving in France. In natural sciences, most articles are published in international journals; authors must therefore comply with the policies of their publishers, irrespective of their nationality. For humanities and social sciences, where publication tends to be distributed among many small journals, portals have been created to provide electronic publishing, with varied access policies. Open archives repositories have been in existence in France since 2001; from 2006, a proactive policy led the main research agencies and universities to coordinate their actions towards a common archiving platform, HAL (Hyper Articles on Line), operated by CNRS (Centre National pour la Recherche Scientifique), with individual portals, either thematic or institutional. HAL stores now the majority of open access records – presently some 10–15% of French output – and is growing almost exponentially.  相似文献   
252.
The overall traffic of droplets in a network of microfluidic channels is strongly influenced by the liquid properties of the moving droplets. In particular, the effective hydrodynamic resistance of individual droplets plays a key role in their global behavior. Here we propose two simple and low-cost experimental methods for measuring this parameter by analyzing the dynamics of a regular sequence of droplets injected into an “asymmetric loop” network. The choice of a droplet taking either route through the loop is influenced by the presence of previous droplets that modulate the hydrodynamic resistance of the branches they are sitting in. We propose to extract the effective resistance of a droplet from easily observable time series, namely, from the choices the droplets make at junctions and from the interdroplet distances. This becomes possible when utilizing a recently proposed theoretical model based on a number of simplifying assumptions. Here we present several sets of measurements of the hydrodynamic resistance of droplets, expressed in terms of a “resistance length.” The aim is twofold: (1) to reveal its dependence on a number of parameters, such as the viscosity, the volume of droplets, their velocity as well as the spacing between them. At the same time (2), by using a standard measurement technique, we compare the limitations of the proposed methods. As an important result of this comparison, we obtain the range of validity of the simplifying assumptions made in the theoretical model.  相似文献   
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Chronic exertional compartment syndrome (CECS) is characterized by pain occurring during physical activity. As clinical examination is not sufficient to diagnose it, intracompartmental pressure (ICP) measure is used for CECS confirmation. Numerous clinical signs are reported but their diagnosis predictive ability has never been studied. We aimed to determine if the 12 classically reported clinical signs are predictive of CECS. We performed a single-centre retrospective cohort study on patients referred for CECS suspicion. Patients were asked to run on a treadmill. When pain occurred, post-exercise ICP was performed. We diagnosed CECS if the ICP was ≥30?mmHg and used a logistic regression to calculate the predictive value of clinical signs. One hundred twenty-five patients were evaluated. Ninety-six had CECS and 29 did not, according to the ICP 30?mmHg cut-off. Anterior and lateral compartments were the most frequently affected. After exercise, mean ICP was 58.6?mmHg?±?20.5 in the group with CECS versus 20.9?mmHg?±?4 in the group without (p?p?p?相似文献   
255.
A tube-in-square-pipe microfluidic glass cell has been developed for studying the aggregation and fiber formation from regenerated silk solution by in-situ small-angle X-ray scattering using synchrotron radiation. Acidification-induced aggregation has been observed close to the mixing point of the fibroin and buffer solution. The fibrous, amorphous material is collected in a water bath. Micro-wide-angle X-ray scattering of the dried material confirms its β-sheet nature.  相似文献   
256.
This paper describes the activities of the World Intellectual Property Organization (WIPO) and presents its programme for the next few years in the field of copyright, with particular emphasis on aspects of interest to publishers.  相似文献   
257.
Analysis of coaching science research published from 1970-2001   总被引:1,自引:0,他引:1  
The study followed a four-phase design. In Phase I an exhaustive search was conducted for all English language coaching research published in journals from 1970 to 2001. In Phase II, copies of the research were obtained. An expert panel conducted a manual search and a review in Phase III to address validity. Analysis of the research was completed in Phase IV (Culver Gilbert, & Trudel, 2003; Silverman & Skonie, 1997). Over 1,100 articles were reviewed, and 610 met the inclusion criteria. Selected findings include: (a) a relatively low mean spread across many journals, (b) a focus on coaching behavior using quantitative methodologies, and (c) a primary emphasis on team sports in school contexts.  相似文献   
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