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81.
82.
Higher Education - Scholars have widely recognised the importance of academic relationships between students at the university. While much of the past research has focused on studying their...  相似文献   
83.
Knowledge Management Research & Practice - Nowadays knowledge has become a key asset for firms in order to build a sustainable competitive advantage. The environment changes quickly and...  相似文献   
84.
Microfluidic devices allow for the production of physiologically relevant cellular microenvironments by including biomimetic hydrogels and generating controlled chemical gradients. During transport, the biomolecules interact in distinct ways with the fibrillar networks: as purely diffusive factors in the soluble fluid or bound to the matrix proteins. These two main mechanisms may regulate distinct cell responses in order to guide their directional migration: caused by the substrate-bound chemoattractant gradient (haptotaxis) or by the gradient established within the soluble fluid (chemotaxis). In this work 3D diffusion experiments, in combination with ELISA assays, are performed using microfluidic platforms in order to quantify the distribution of PDGF-BB and TGF-β1 across collagen and fibrin gels. Furthermore, to gain a deeper understanding of the fundamental processes, the experiments are reproduced by computer simulations based on a reaction-diffusion transport model. This model yields an accurate prediction of the experimental results, confirming that diffusion and binding phenomena are established within the microdevice.  相似文献   
85.
This study aimed to analyse the effect of growth during a summer break on biomechanical profile of talented swimmers. Twenty-five young swimmers (12 boys and 13 girls) undertook several anthropometric and biomechanical tests at the end of the 2011–2012 season (pre-test) and 10 weeks later at the beginning of the 2012–2013 season (post-test). Height, arm span, hand surface area, and foot surface area were collected as anthropometric parameters, while stroke frequency, stroke length, stroke index, propelling efficiency, active drag, and active drag coefficient were considered as biomechanical variables. The mean swimming velocity during an all-out 25 m front crawl effort was used as the performance outcome. After the 10-week break, the swimmers were taller with an increased arm span, hand, and foot areas. Increases in stroke length, stroke index, propelling efficiency, and performance were also observed. Conversely, the stroke frequency, active drag, and drag coefficient remained unchanged. When controlling the effect of growth, no significant variation was determined on the biomechanical variables. The performance presented high associations with biomechanical and anthropometric parameters at pre-test and post-test, respectively. The results show that young talented swimmers still present biomechanical improvements after a 10-week break, which are mainly explained by their normal growth.  相似文献   
86.
Abstract

The aim was to examine the injuries sustained by Spanish football players in the First Division and to compare injury-related variables in the context of both competition and training. The injury data were prospectively collected from 16 teams (427 players) using a specific web-based survey during the 2008/2009 season. A total of 1293 injuries were identified (145 were recurring injuries). The overall injury incidence was 5.65 injuries per 1000 h of exposure. Injuries were much more common during competition than during training (43.53 vs. 3.55 injuries per 1000 h of exposure, P < 0.05). Most of the injuries (89.6%) involved the lower extremities, and overuse (65.7%) was the main cause. Muscle and tendon injuries were the most common types of injury (53.8%) among the players. The incidence of training injuries was greater during the pre-season and tended to decrease throughout the season, while the incidence of competition injuries increased throughout the season (all P < 0.05). In conclusion, the results of this study suggest the need for injury prevention protocols in the First Division of the Spanish Football League to reduce the number of overuse injuries in the muscles and tendons in the lower extremities. In addition, special attention should be paid during the pre-season and the competitive phase II (the last four months of the season) in order to prevent training and competition injuries, respectively.  相似文献   
87.
Much comparative research into education-related beliefs has exploited questionnaires developed in one culture for use in another. This has been particularly the case in mathematics education, the focus of this paper. In so doing, researchers have tended to assume that translation alone is sufficient to warrant a reliable and valid instrument for cross-cultural research, prompting concerns that a number of necessary equivalences are unlikely to have been addressed. In this paper, we consider the nature of these equivalences before examining the literature of a different field, healthcare research, to synthesise an approach to instrument adaptation that is pragmatic but rigorous. Finally, we demonstrate how this pragmatic approach, incorporating extensive cognitive interviews, enabled us to adapt and refine a mathematics-related beliefs questionnaire, developed in Flanders, for use with students aged 14–15 in England and Spain. Analyses indicate that the instrument so developed is multidimensional, reliable and cross-culturally valid. Some implications are discussed.  相似文献   
88.

Objectives

During intrafamilial conflicts children are often innocent bystanders, caught in the crossfire. In such situations, they are at increased risk to become directly involved in abusive verbal behavior of the perpetrator, and exposed to being shouted or yelled at, threatened, rejected and even physically abused. The present study has two main objectives: (1) ascertain a national base rate of intrafamilial conflicts and physical violence at home among Icelandic adolescents; and (2) to investigate the association of witnessing and/or having been a part of intrafamilial conflict or physical violence at home with variables that relate to mental health and well-being.

Methods

The participants were 3,515 students, 14- and 15-year-old, in the national compulsory school system in Iceland. As a part of the 2003 ESPAD survey, each pupil was asked about experiences of severe verbal arguments and physical violence at home as well as their background, behaviors, and mental health assessed with the use of tested measurement scales such as the Symptom Distress Checklist 90 (SCL-90) and the Rosenberg Self-Esteem Scale.

Results

About 22% of the participants stated that they had witnessed a severe verbal argument between parents and 34% stated that they had been involved in a severe verbal argument with parents. This rate was slightly higher for girls compared to boys. All together 7% of adolescents had witnessed physical violence at home where an adult was involved and 6% of the participants stated that they had experiences of being involved in physical violence at home where an adult was involved. Witnessing or being involved in severe verbal arguments at home and/or witnessing or being involved in physical violence with an adult was significantly associated with greater levels of depression, anger, and anxiety, and negatively related with self-esteem (p < 0.01).

Conclusions

Many adolescents in Iceland witness severe parental verbal arguments or physical violence between adults in their homes and some are directly involved in such acts. It affects their long-term emotional and behavioral development and well-being.

Practice implications

Preventive measures have to be implemented at an early age and should include, but not be limited to, information on disciplining and upbringing of children and the negative impact of intrafamilial conflicts on the long-term health of their children. Due attention should be given to the health and well-being of children where such violence is known to occur.  相似文献   
89.
We describe the results of electromigration desalination of two soluble salt-contaminated Galician granites. The efficacy of electromigration, which had not been previously applied to granite, was assessed for two types of granite contaminated with a 20% NaCl solution and seawater. Desalination effectiveness was evaluated as follows: (1) analysis of anode and cathode ion content during testing; (2) analysis of ions at different distances from the electrodes after testing; (3) pH assessment of the stone surfaces; and (4) evaluation of colour changes. Results were very satisfactory; by the end of testing, chloride was reduced by almost 100% in both the NaCl and seawater contaminated samples. Sulfate reduction was also significant, despite this ion's lower mobility. The granite pH values remained close to neutral and colour changes were minimal. The difference in effectiveness of the process for the two types of stone was associated with their dissimilar pore structure.  相似文献   
90.
Science & Education - Science and mathematics are universal endeavors. However, the historical perspective of science and mathematics has been westernized across the curriculum in the USA....  相似文献   
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