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11.
The use of human material in anatomy education depends upon the generosity of body donors. However, little is known regarding the demographics of body donors in Brazil, where voluntary body donation is a relatively rare phenomenon. Hence, the aim of the present study was to elucidate the demographic profile of applicants to the Body Donation Program (BDP) at the Federal University of Health Sciences of Porto Alegre in Brazil, as well as to assess whether the observed characteristics of body donors are unique to that sample, or if they merely reflect the characteristics of the regional population. Information derived from the specific forms filled out by donors between January 2008 and June 2016 at the time of registration were collected. Data from 416 forms were analyzed. Based on this study, the typical applicant in Brazil is typically a white female (67.4%), over 60 years of age (60.3%), unmarried or single (70.6%), affiliated with a religious group (89.1%), of middle class background (40.4%), who has completed high school and/or holds a university degree (93.8%). The motivation of donors was, in most cases, an altruistic gesture, represented by the desire to help society and science. Elucidating these demographic characteristics of potential donors may help identify the target public to which information regarding body donation campaigns could be directed. Anat Sci Educ 10: 475–486. © 2017 American Association of Anatomists.  相似文献   
12.
To evaluate the orthographic and phonological processing skills of developmental dyslexics, we (a) examined their abilities to exploit properties of orthographic redundancy and (b) tested whether their phonological deficit extends to spelling-to-sound connections for large-grain size units such as syllables. To assess the processing skills in dyslexics, we utilized the illusory conjunction paradigm to investigate the nature of reading units in French dyslexic and control children matched in reading age. In control children, reading units were defined by both orthographic redundancy and phonological syllable information. In dyslexics, however, reading units were defined only by orthographic redundancy. Therefore, despite their impairment in reading acquisition, developmental dyslexics have the ability to encode and exploit letter frequency co-occurrences. In contrast, their access to phonological syllables from letters was impaired, suggesting that their phonological deficit extends to large grain-size phonological units.  相似文献   
13.
本文运用Wagner平面分异法(Wagner Groundplan Divergence Method),对中国东北 泥炭藓植物14个种和1变种进行了种系发生的探讨。根据所选出的21个泥炭藓不同部位的 形态学和解剖学的性状特征,将其同已知的姐妹群或其它邻近群的同源特征系列中的相应性 状做比较并遵从物种的个体发育顺序、类群趋向等标准,确定性状梯度极向,即找出祖征和衍 征,以期较系统地、定量地描述泥炭藓属种系发生过程。研究结果表明,在泥炭藓的14种和1变种中,Sphagnum magellanicum 最为原始,S. girgensohnii 和S.fimbriatum 最为进化。  相似文献   
14.
The purpose of this study was to analyze pedaling cadence, pedal forces, and muscle activation of triathletes during cycling to exhaustion. Fourteen triathletes were assessed at the power output level relative to their maximal oxygen uptake (355 +/- 23 W). Cadence, pedal forces, and muscle activation were analyzed during start, middle, and end test stages. Normal and tangential forces increased from the start to the end of the test (-288 +/- 33 to -352 +/- 42 N and -79 +/- 45 to -124 +/- 68 N, respectively) accompanied by a decrease in cadence (96 +/- 5 to 86 +/- 6 rpm). Muscle activation increased from the start to the middle and the end in the gluteus maximus (27 +/- 5.5% and 76 +/- 9.3%) and in the vastus lateralis (13 +/- 3.5% and 27 +/- 4.4%), similar increase was observed from the start to the end in the rectus femoris and the vastus medialis (50 +/- 9.3% and 20 +/- 5.7%, respectively). Greater normal force along with enhanced activation of knee and hip extensor muscles is linked with fatigue and declines in cadence of triathletes during cycling to exhaustion.  相似文献   
15.
ABSTRACT

This study investigated the effects of maturity status on knee extensor torque and vastus lateralis architecture of young soccer players. Thirty-four males aged 13–18 years were divided into two groups: pubescent (PUB, n = 15) and postpubescent (POSP, n = 19). Torque by angle interaction was established for absolute [F(2.649, 84.771) = 9.066, p < 0.05] and relative to body mass [F(2.704, 86.533) = 4.050, p < 0.05] isometric torque with the POSP group showing greater values. Muscle volume torque-angle relationship was similar between groups. Absolute, relative to body mass, and relative to muscle volume concentric and eccentric torque-velocity relationship showed a non-significant interaction but a significant group effect in favour the POSP group for absolute and concentric torque relative to body mass. Torque-angle and torque-velocity relationship normalized by body mass allometric exponents showed a non-significant interactions and group effects. Muscle thickness (3.6 ± 0.6 vs. 3.8 ± 0.6 cm), fascicle length (8.3 ± 1.4 vs. 8.9 ± 1.6 cm) and pennation angle (15.0 ± 2.3 vs. 14.3 ± 3.2 degrees) was similar between PUB and POSP groups, respectively. Maturity status did not show a significant effect on muscle architecture and on isometric and dynamic torques when allometrically normalized.  相似文献   
16.
Distractibility is the propensity to behaviorally react to irrelevant information. Although children are more distractible the younger they are, the precise contribution of attentional and motor components to distractibility and their developmental trajectories have not been characterized yet. We used a new behavioral paradigm to identify the developmental dynamics of components contributing to distractibility in a large cohort of French participants balanced, between age groups, in gender and socioeconomic status (N = 352; age: 6–25). Results reveal that each measure of these components, namely voluntary attention, distraction, impulsivity, and motor control, present a distinct maturational timeline. In young children, increased distractibility is mostly the result of reduced sustained attention capacities and enhanced distraction, whereas in teenagers, it is the result of decreased motor control and increased impulsivity.  相似文献   
17.
This paper presents the methodology, results and difficulties encountered in the development and delivery of a course through the Internet. The course, which is about the application of information technology to education, is being delivered using the AulaNet environment, which is groupware for the creation, participation and maintenance of Web-based courses. A model for group work is provided. This paper also shows how this kind of environment can be used to provide support, and to facilitate and manage cooperative learning.  相似文献   
18.
We present numerical simulations of DNA-chip hybridization, both in the “static” and “dynamical” cases. In the static case, transport of free targets is limited by molecular diffusion; in the dynamical case, an efficient mixing is achieved by chaotic advection, with a periodic protocol using pumps in a rectangular chamber. This protocol has been shown to achieve rapid and homogeneous mixing. We suppose in our model that all free targets are identical; the chip has different spots on which the probes are fixed, also all identical, and complementary to the targets. The reaction model is an infinite sink potential of width dh, i.e., a target is captured as soon as it comes close enough to a probe, at a distance lower than dh. Our results prove that mixing with chaotic advection enables much more rapid hybridization than the static case. We show and explain why the potential width dh does not play an important role in the final results, and we discuss the role of molecular diffusion. We also recover realistic reaction rates in the static case.  相似文献   
19.
Abstract

We investigated the mechanical properties of the triceps surae between professional, junior, and non-football players. Fifty-nine men participated in this study. The mechanical properties of the right legs’ triceps surae were measured in vivo using a free oscillation technique; no significant differences existed between the groups. The mean results for musculo-articular stiffness, damping coefficient, and damping ratio were as follows: professional football players (21523 N· m?1, 330.8 N · s · m?1, and 0.201); junior football players (21063 N · m?1, 274.4 N · s · m?1, and 0.173); and non-players (19457 N · m?1, 281.5 N · s · m?1, and 0.184). When analysed according to position, the results were as follows: defender (21447 N · m?1, 308.6 N · s · m?1, and 0.189); midfielder (20762 N · m?1, 250.7 N · s · m?1, and 0.157); winger (21322 N · m?1, 335.1 N · s · m?1, and 0.212); forward (22085 N · m?1, 416.2 N · s · m?1, and 0.254); and non-players (19457 N · m?1, 281.5 N · s · m?1, and 0.184).

Thus, football training, football games, and the position played had no effect on triceps surae mechanical properties. These results may be attributed to opposing adaptations between different types of training that are usually implemented in football. Alternatively, the minimum strain amplitude and/or frequency threshold of the triceps surae required to trigger adaptations of mechanical properties might not be achieved by football players with football training and matches.  相似文献   
20.
This study examined the symptoms of exhaustion, school stress and anxious school refusal from a comparative developmental perspective in French adolescents enrolled in public and private general, technological and vocational schools. It is particularly important to consider academic stress levels, anxiety and school burnout in middle and high school students as they are linked to many mental health problems, such as depression or suicidal thoughts. In this study, four hundred and ninety-three adolescents completed an online questionnaire consisting of the School Burnout Inventory, the Echelle Toulousaine de Stress Scolaire perçu and the School refusal evaluation was developed. The results show a very high percentage of suffering among teenagers. The young people most affected are high school students and more particularly students in 10th and 12th grade, with nearly three-quarters of them suffering from school burnout and/or high school stress, without any distinction between the sexes or the type of schooling.  相似文献   
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