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291.
This study shows that the sandstone used in the construction of the Church of San Mateo in Tarifa (Cádiz, Spain) is highly sensitive to processes of decay because of a combination of factors that are intrinsic and extrinsic to the material. The mineralogy, texture and porous system of the sandstone and the proximity of the church to the sea all play a part in these processes. X-ray diffraction reveals that there are interstratified chlorite/smectite clays among the minerals that make up the rock. These mixed layer clays have been shown to undergo hydric expansion. This phenomenon may be accompanied and augmented by the presence of NaCl which acts as an electrolyte in osmotic swelling processes. Two varieties of sandstone were used in the construction of the church, namely grey sandstone and brown sandstone. The latter is more porous and undergoes greater hydric expansion, showing a higher degree of deterioration. Ultrasound analysis has demonstrated that both varieties are anisotropic because they contain bedding planes and are affected by the preferred orientation of the phyllosilicates in the rock. The anisotropic nature of these stones was confirmed by capillary suction tests. The capillary front reaches a relatively low height which means that when water is absorbed, the anisotropic textural properties combined with the presence of chlorite–smectite mixed layers in the sandstone result in mechanical (shear) stress between the first few centimetres of the wet stone and the dry area behind. The latter effect favours the development of flakes, so causing the decay of the ornamental stone and the church façade.  相似文献   
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Based on the cross-cultural adjustment, education, and job performance literatures, an international student performance taxonomy is proposed and tested with a sample of 272 business exchange students from nine Asian, European, and North American countries studying in Mexico. Results of confirmatory factor analyses provided tentative support for an eight-factor taxonomy comprised of performance dimensions labeled: engaging in academic and non-academic tasks, communicating with host nationals, writing and using the local language, helping and cooperating with other international students, demonstrating effort in an academic setting, maintaining personal discipline, developing social and personal relationships with host nationals, and adjusting to general conditions of living abroad. Issues concerning the practical implications of these findings as well as the generalizability of the confirmed performance taxonomy to other educational and work contexts are discussed.  相似文献   
294.
Anecdotal evidence points to a falling standard of living for the educated in Venezuela. During this same period, President Hugo Chávez implemented several education reforms. We focus on a major university education reform known as Mission Sucre and its potential impact on returns to university education. First, we show that returns to education decreased significantly in Venezuela from 2002 to 2008. Subsequently, we explore the impact of the program on non-program participants and provide evidence that a substantial part of the falling returns at the tertiary level can be linked to Mission Sucre. Our results suggest that the reform created a negative externality on students who did not participate in the program, leading to a 2.7 percentage point decline in returns to university education for non-Mission Sucre students in the 23–28 age cohort.  相似文献   
295.
The Texas Electronic Coalition for Physics was established in 2000 as a means of demonstrating that by linking together, small programs can maintain their vitality in higher education. Using Interactive Television, the Internet, telephones, faxes, and other electronic media, five physics programs scattered across the state of Texas formed a distributed physics department. In addition to jointly offering lecture courses, the group (i) established procedures for operating as a unified entity, (ii) encouraged research regardless of location, (iii) provided a locus for professional camaraderie, (iv) created a distance-based advanced physics laboratory course, and (v) developed assessment tools for measuring success in a distance environment. Through these, the coalition demonstrated that a distributed department can carry out all of the functions associated with a traditional department.  相似文献   
296.
Purpose: The talent identification and selection process in young male soccer players is mainly focused on anthropometrics and physical performance, but social factors are also considered in this process. The purpose of this study was to test the existence of the relative age effect and its possible influence on anthropometrics and physical performance and to analyze coaches’ efficacy expectations. Method: Data for 564 young male soccer players (Mage = 13.7 ± 1.5 years; Mweight = 53.7 ± 11.6 kg; Mheight = 160.2 ± 11.6 cm) included their birth quartile, maturity status, anthropometrics, a physical test battery, and coaches’ efficacy expectations. Results: Early-born players were overrepresented (< .05). Early-born players were not statistically taller, heavier, or better at physical performance (> .05) when maturation and chronological age were controlled as confounding factors. However, coaches expected more from early-born players (< .05), and the inferential analysis showed likely to very likely worthwhile differences between the coaches’ expectations for players born in the first quartile of the year and those born in the fourth quartile of the year. Conclusions: Anthropometrical and physical performance variables were not affected by birth quartile, and coaches’ efficacy expectations were related to the relative age effect.  相似文献   
297.
Does a young football (soccer) player’s birthdate affect his prospects in the sport? Scholars have found a correlation between early births in the competition year among young players within the same cohort and improved chances in sports as they advance to other stages. This article is one of the first studies to ask this question about a male premier league in Latin America – the Argentinian ‘A’ league. It uses a large-N data-set of all players in the period 2000–2012, around 3000 players. The article finds a large effect of the player’s relative age on his prospect to become a professional, though the effect is only present in the case of Argentinian-born players. The effect evaporates once a set of measures are employed to compare professional players with one another. The article contributes to the discussion of the biased effect of seemingly neutral institutional policies, and its conclusions may shed light in other areas.  相似文献   
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As part of a child development course in an undergradute early childhood teacher preparation program, students completed a home visit project with a family of a culture other than their own. This report examines the assignment's effectiveness in helping students become aware of the cultural nature of human development and the role of the family in the child's growth and development. Student responses obtained through focus groups, papers, field notes, and course evaluations included 1) reflections on the nature of the experience; 2) reactions to the role of researcher in the home of relative strangers and 3) evaluation of the learning. Although students seem to have achieved some understanding of the role of family and culture, the further step of recognizing culture as fundamental to development was generally not an outcome of the present intervention.  相似文献   
300.
Abstract

The aim of present study was to examine the relationships between serum and salivary values of free testosterone, dehydroepiandrosterone, and cortisol before and after a session of resistance exercise. Twenty-eight healthy men (mean age 40 years, s = 4) participated in the present study. Serum and salivary samples were collected at rest and after a multiple-sets resistance exercise protocol, of approximately 25 minutes duration. Concentrations of free testosterone, dehydroepiandrosterone, and cortisol were measured using radioimmunoassay kits. No significant correlation was observed between serum free testosterone and salivary testosterone (r = 0.22 to 0.26, P > 0.05). Serum cortisol was significantly correlated with salivary cortisol before (r = 0.52, P = 0.005) and after (r = 0.62, P = 0.001) the exercise protocol. Serum and salivary concentrations of dehydroepiandrosterone were significantly correlated before (r = 0.68, P < 0.001) and after (r = 0.7, P < 0.001) exercise. The results of the present study suggest that even under exercise conditions, the salivary values of cortisol and dehydroepiandrosterone can reflect the behaviour of these hormones in blood. However, further studies are necessary to verify if salivary testosterone reflects the behaviour of serum free testosterone during resistance exercise.  相似文献   
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