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911.
912.
Observations of the contemporary news media environment often revolve around the topics of ideological polarization and blurred boundaries between mass and interpersonal communication. This study explores these topics through a focus on the association between ideologically oriented online news use, commenting on online news, and political participation. We hypothesize that both ideological online news use generally and proattitudinal online news use are positively related to political participation and that online news commenting creates “differential gains” by augmenting these relationships. Yet we also hypothesize that counterattitudinal online news use is negatively related to political participation and that online news commenting creates “differential losses” by exacerbating this relationship. Analyses of two independently collected and nationally representative surveys found that frequent ideological online news use, proattitudinal online news use, and commenting are all positively related to political participation. We found no evidence for differential gains as a result of online commenting but only for differential losses—counterattitudinal online news use interacts with commenting to create a negative relationship with political participation.  相似文献   
913.
IntroductionMost laboratories routinely determine haemolysis, icterus and lipemia indices to identify lipemic samples and reject potentially affected results. Hypertriglyceridemia is the most common cause of lipemia and severe hypertriglyceridemia (≥ 11.3 mmol/L) is a major risk factor of acute pancreatitis.Laboratory analysisA 56-year-old woman attended the outpatient clinic for a follow-up visit 1 month after a kidney transplantation. Her immunosuppressive therapy consisted of corticosteroids, cyclosporine, and mycophenolic acid. The routine clinical chemistry sample was rejected due to extreme lipemia. The comment “extreme lipemic sample” was added on the report, but the requesting physician could not be reached. The Cobas 8000 gave a technical error (absorption > 3.3) for the HIL-indices (L-index: 38.6 mmol/L) which persisted after high-speed centrifugation. The patient was given a new appointment 2 days later. The new sample was also grossly lipemic and gave the same technical error (L-index: 35.9 mmol/L).What happenedThe second sample was manually diluted 20-fold after centrifugation to obtain a result for triglycerides within the measuring range (0.10–50.0 mmol/L). Triglycerides were 169.1 mmol/L, corresponding to very severe hypertriglyceridemia. This result was communicated to the nephrologist and the patient immediately recalled to the hospital. She received therapeutic plasma exchange the next day and did not develop acute pancreatitis.Main lessonThis case illustrates the delicate balance between avoiding the release of unreliable results due to lipemia and the risk of delayed diagnosis when results are rejected. Providing an estimate of the degree of hypertriglyceridemia might be preferable to rejecting the result.  相似文献   
914.
In this work, we present a new approach for loss probability estimation in a single server link. We show how to get the estimates analytically once we assume multifractal input traffic. In order to make the estimation procedure numerically tractable without losing the accuracy, we propose the use of a Gaussian mixture model to represent the heavy tail distribution of modern network traffic trace. The adopted evaluation procedure is based on two performance measures: empirical traffic arrival load distribution and loss probability at connection. Extensive experimental tests validate the efficiency and accuracy of the proposed loss probability estimation approach against the results obtained by simulations with real traffic and by comparing with other multifractal approaches suggested in the literature.  相似文献   
915.
Open-content communities that focus on co-creation without requirements for entry have to face the issue of institutional trust in contributors. This research investigates the various ways in which these communities manage this issue. It is shown that communities of open-source software—continue to—rely mainly on hierarchy (reserving write-access for higher echelons), which substitutes (the need for) trust. Encyclopedic communities, though, largely avoid this solution. In the particular case of Wikipedia, which is confronted with persistent vandalism, another arrangement has been pioneered instead. Trust (i.e. full write-access) is ‘backgrounded’ by means of a permanent mobilization of Wikipedians to monitor incoming edits. Computational approaches have been developed for the purpose, yielding both sophisticated monitoring tools that are used by human patrollers, and bots that operate autonomously. Measures of reputation are also under investigation within Wikipedia; their incorporation in monitoring efforts, as an indicator of the trustworthiness of editors, is envisaged. These collective monitoring efforts are interpreted as focusing on avoiding possible damage being inflicted on Wikipedian spaces, thereby being allowed to keep the discretionary powers of editing intact for all users. Further, the essential differences between backgrounding and substituting trust are elaborated. Finally it is argued that the Wikipedian monitoring of new edits, especially by its heavy reliance on computational tools, raises a number of moral questions that need to be answered urgently.  相似文献   
916.
Most studies of the effects of the Bayh-Dole Act have focused on universities. In contrast, we analyze patenting activity at two prominent national laboratories, Sandia National Laboratories and the National Institute of Standards and Technology before and after the enactment of this legislation and the Stevenson-Wydler Act. It appears as though the enactment of Bayh-Dole and the Stevenson-Wydler Act were not sufficient to induce an increase in patenting at these labs. However, the establishment of financial incentive systems, embodied in passage of the Federal Technology Transfer Act, as well as the allocation of internal resources to support technology transfer, stimulated an increase in such activity.  相似文献   
917.
Monoclonal antibodies played a key role in the development of the biotechnology industry of the 1980s and 1990s. Investments in the sector and commercial returns have rivaled those of recombinant DNA technologies. Although the monoclonal antibody technology was first developed in Britain, the first patents were taken out by American scientists. During the first Thatcher government in Britain, blame for the missed opportunity fell on the scientists involved as well as on the National Research and Development Corporation, which had been put in place after World War II to avoid a repeat of the penicillin story, when patent rights were not sought. Instead of apportioning the blame, this essay suggests that despite past experiences and despite the new channels that were in place, Britain was not in a "patent culture" in the 1970s. It traces the long and painful process that made a commercial attitude among publicly funded British research scientists and in a civil service institution like the Medical Research Council both possible and desirable. In this process the meaning of the term "public science" also changed dramatically.  相似文献   
918.
In this study, we used tensiomyography (TMG) to assess muscle status immediately after an ultra-endurance triathlon. Maximal radial displacement or deformation of the muscle belly, contraction time, delay time, sustain time, and relaxation time were measured for both legs, and dependent t-tests were used to compare means between the beginning and end of the race. The 19 men assessed (age 37.9 ± 7.1 years; height 177.5 ± 4.6 cm; weight: 73.6 ± 6.5 kg) participated in the 2009 edition of the Lanzarote Ironman. Deterioration in the neural response was observed for contraction time (P = 0.008) and relaxation time (P = 0.011), with a moderate decrease in the response time (sustain time) and a loss in muscle stiffness (deformation of the muscle belly). The effect of muscle fatigue on the rectus femoris and biceps femoris was different. Barely any changes in contraction time, relaxation time, sustain time, and deformation of the muscle belly were observed, while only the contraction response time decreased to a significant extent (reduction in delay time; P = 0.003). The considerable loss in contractile capacity induced by a long-distance race was reflected in changes in the neuromuscular response and fluctuations in the contractile capacity of the muscle. These modifications, derived from a prolonged, exhausting effort, can be assessed in a simple, non-aggressive, non-invasive way using tensiomyography.  相似文献   
919.
依据中国体育及相关产业统计数据,运用偏离份额分析法和区位熵分析法对华地区体育产业结构进行实证研究。研究认为:华东地区体育产业部门中体育用品服装鞋帽销售和制造的份额优势和竞争优势明显;其他体育产业部门具有一定份额优势,但竞争优势不明显;体育用品服装鞋帽制造和体育建筑专业化程度较高。促进各个体育产业部门协调发展,加强优势产业部门创新发展,完善产业政策和布局是优化华东地区体育产业结构的重要途径。  相似文献   
920.
The approach in this paper is based on the principles of action research and rapid prototyping. The paper shows the current status of a ‘bottom-up’ research process dedicated to continuously developing and improving management instruments that suit the requirements of small and medium-sized enterprises (SMEs): pragmatic, easy-to-use and generating direct practical benefit. As a result, this paper links the concept of intangibles to the practical strategy development process in SMEs. The integration shown concerns several challenges: (1)?Integrate the internal and external perspective on intangibles, and, by that, link the concept of intellectual capital (IC) as a resource-based view with the concept of customer value as a market-based view. (2)?Integrate the theoretical concept of IC with a methodology for comprehensive strategy development. (3)?Integrate the formulation and implementation of business strategies taking into account the actual practice in SMEs.  相似文献   
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