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21.
The aim of this study was to assess the effects of a single session of cold or thermoneutral water immersion after a one-off match on muscular dysfunction and damage in soccer players. Twenty-male soccer players completed one match and were randomly divided into cryotherapy (10 min cold water immersion, 10°C, n = 10) and thermoneutral (10 min thermoneutral water immersion, 35°C, n = 10) groups. Muscle damage (creatine kinase, myoglobin), inflammation (C-reactive protein), neuromuscular function (jump and sprint abilities and maximal isometric quadriceps strength), and delayed-onset muscle soreness were evaluated before, within 30 min of the end, and 24 and 48 h after the match. After the match, the players in both groups showed increased plasma creatine kinase activity (30 min, 24 h, 48 h), myoglobin (30 min) and C-reactive protein (30 min, 24 h) concentrations. Peak jump ability and maximal strength were decreased and delayed-onset muscle soreness increased in both groups. However, differential alterations were observed between thermoneutral water and cold water immersion groups in creatine kinase (30 min, 24 h, 48 h), myoglobin (30 min), C-reactive protein (30 min, 24 h, 48 h), quadriceps strength (24 h), and quadriceps (24 h), calf (24 h) and adductor (30 min) delayed-onset muscle soreness. The results suggest that cold water immersion immediately after a one-off soccer match reduces muscle damage and discomfort, possibly contributing to a faster recovery of neuromuscular function.  相似文献   
22.
For the general population, sharks have a reputation that does not really fit with their biological and ecological nature. Informal surveys often classify sharks as dangerous, aggressive and/or man-eaters. This apparent common knowledge seems difficult to detach from the conscience of many worldwide zoo visitors, even with the help of shark-focused educational programmes. As so, how can zoos and aquariums contribute to a change in this paradigm? Are the education and conservation strategies effective to the average zoo visitor? In this study, young visitors’ perceptions regarding sharks were assessed with the goal of identifying a valid Learning Progression, thus helping to update and develop different and more effective educational strategies and methodologies. The study took place at Zoomarine, an oceanographic park located in southern Portugal, with visitors aged between 8 and 16. A case study was conducted using a qualitative research approach (drawings and interviews) resulting in a Learning Progression Hypothesis. The proposed Learning Progression is composed of three knowledge levels for the participants’ biological perceptions regarding sharks. The results of this study showed a clear predominance of anthropomorphic and anthropocentric visions, as well as a utilitarian view of sharks and ecosystem, thus conditioning the visitors’ epistemological knowledge.  相似文献   
23.
Abstract

Purpose

Information technology (IT) has tremendous potential for fostering grassroots development and the Indian government has created various capital-intensive computer networks to promote agricultural development. However, research studies have shown that information technology investments are not always translated into productivity gains due to poor computer use by employees. In this context, a research investigation was conducted to develop a Computer Utilization Model that explains how individual and organizational factors influence computer utilization in extension organizations in India.  相似文献   
24.
This paper presents conditions to assure the exponential stability in probability for autonomous switching linear systems. The switching signal acting on the autonomous system produces intervals that follow independent, identically distributed stochastic processes—the stability then follows by verifying simple-to-check linear matrix inequalities.  相似文献   
25.
ABSTRACT

This article explores popular media as resources for judgment in how settled migrants in Europe imagine solidarities toward newer arrivals seeking entry into the region. It discusses the news and entertainment consumption of Filipino nurses in London and how this figures in their imaginary of social and political bonds with refugees. Drawing on ethnographic interviews, I argue that these Filipino migrants can only articulate a compromised solidarity: one fractured between empathy with refugees and concern about what these newer arrivals might mean for settled migrants in the city. I then explain how the media contribute to this fracturing. One way is that the xenophobia in popular media content on social media leads the Filipinos to assert their difference with other migrants, including refugees. A second is that the Filipinos deploy popular media content, especially on British television, to assert that they belong to UK society more than other migrants, again including refugees.  相似文献   
26.
ABSTRACT

The recruitment of athletes with limited resources is a global problem in professional sports. In US Major League Baseball, the experience of the Oakland Athletics’ general manager in the last decade turned his “Moneyball” model into a synonym of quantitative analysis in the transfer market of baseball players. His strategy focused on hiring players with outstanding technical skills but relatively low market value. This study adapted this model to the framework of a multiple criteria decision aid (MCDA), by selecting undervalued players who have complementary abilities. The novelty here refers to the joint use of four algorithms explored by the composition of probabilistic preferences (CPP) (i.e., ranking, classification, dynamic evaluation and regularity analysis) and their application to soccer player performance evaluation. The new model analysed the recent transfer of a left-back soccer player to Europe. The results indicated 12 opportunities for better investment, among 32 left and right-back players considered. Two years later, the value of the same player was considerably lower. He played only five matches in the 2018–2019 season, without scoring or providing any assists. On the other hand, the players better classified by the CPP-MB model presented higher performances and market values.  相似文献   
27.
In this study, the fibers of invasive species Agave americana L. and Ricinus communis L. were successfully used for the first time as new sources to produce cytocompatible and highly crystalline cellulose nanofibers. Cellulose nanofibers were obtained by two methods, based on either alkaline or acid hydrolysis. The morphology, chemical composition, and crystallinity of the obtained materials were characterized by scanning electron microscopy(SEM) together with energy-dispersive X-ray spectroscopy(EDX), dynamic light scattering(DLS), X-ray diffraction(XRD), and Fourier transform infrared(FTIR)spectroscopy. The crystallinity indexes(CIs) of the cellulose nanofibers extracted from A. americana and R. communis were very high(94.1% and 92.7%, respectively). Biological studies evaluating the cytotoxic effects of the prepared cellulose nanofibers on human embryonic kidney 293 T(HEK293 T) cells were also performed. The nanofibers obtained using the two different extraction methods were all shown to be cytocompatible in the concentration range assayed(i.e., 0-500 μg/mL). Our results showed that the nanocellulose extracted from A. americana and R. communis fibers has high potential as a new renewable green source of highly crystalline cellulose-based cytocompatible nanomaterials for biomedical applications.  相似文献   
28.
In this paper we describe an ontological and semiotic model for mathematical knowledge, using elementary combinatorics as an example. We then apply this model to analyze the solving process of some combinatorial problems by students with high mathematical training, and show its utility in providing a semiotic explanation for the difficulty of combinatorial reasoning. We finally analyze the implications of the theoretical model and type of analysis presented for mathematics education research and practice.  相似文献   
29.
Four experiments were conducted to explore outcome-specific transfer from causal predictive judgments to instrumental responding. A video game was designed in which participants had to defend Andalusia from navy and air force attacks. First, they learned the relationship between two instrumental responses (two keys on a standard keyboard) and two different outcomes (destruction of the ships or destruction of the planes). Then they learned to predict which of two different stimuli predicted which outcome. Finally, they had the opportunity of making either of the two instrumental responses in the presence of either stimulus. Transfer was shown as a preference for the response that shared an outcome with the current stimulus. The presentation of the stimulus during the test produced a decrease in the overall rate of response. Responding to a neutral stimulus in Experiments 2 and 3 suggested that this overall decrease in responding was due to a combination of the time needed to process the meaning of the stimulus and the activation of the representation of the outcome in the presence of the stimulus during the test. Transfer between predictive judgments and instrumental responding mirrors the outcome-specific Pavlovian instrumental transfer observed in conditioning studies with rats.  相似文献   
30.
The time, material, and staff‐consuming nature of anatomy's traditional pen‐and‐paper assessment system, the increase in the number of students enrolling in medical schools and the ever‐escalating workload of academic staff have made the use of computer‐based assessment (CBA) an attractive proposition. To understand the impact of such shift in the assessment method, an experimental study evaluating its effect on students’ performance was designed. Additionally, students’ opinions toward CBA were gathered. Second‐year medical students attending a Clinical Anatomy course were randomized by clusters in two groups. The pen‐and‐paper group attended two sessions, each consisting of a traditional sectional anatomy steeplechase followed by a theoretical examination, while the computer group was involved in two similar sessions conducted in a computerized environment. At the end of each of the computer sessions, students in this group filled an anonymous questionnaire. In the first session, pen‐and‐paper group students scored significantly better than computer‐group students in both the steeplechase (mean ± standard deviation: 66.00 ± 14.15% vs. 43.50 ± 19.10%; P < 0.001) and the theoretical examination (52.50 ± 12.70% vs. 39.00 ± 21.10%; P < 0.001). In the second session, no statistically significant differences were found for both the steeplechase (59.50 ± 17.30% vs. 54.50 ± 17.00%; P = 0.085) and the theoretical examination (57.50 ± 13.70% vs. 54.00 ± 14.30%; P = 0.161). Besides, an intersession improvement in students’ perceptions toward CBA was registered. These results suggest that, after a familiarization period, CBA might be a performance equivalent and student accepted alternative to clinical anatomy pen‐and‐paper theoretical and practical examinations. Anat Sci Educ 11: 124–136. © 2017 American Association of Anatomists.  相似文献   
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