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991.
Ana María Delgado García Rafael Oliver Cuello 《Educational technology research and development : ETR & D》2010,58(6):781-790
Education is one of the pillars in which a Welfare State is effectively based on in order to achieve an equitable distribution
of wealth. In contemporary society, knowledge and education are among the most appreciated goods, and everyone should have
the right to acquire them, without distinction of gender, race, age, health or religion. From our experience of over 15 years
at the Universitat Oberta de Catalunya we can claim that virtual learning makes access to education easier for certain population
strata, whereas otherwise, they would be excluded from such a right. A very significant group of students to consider are
women with family burdens who, thanks to this kind of education, are able to gain access to higher education for the first
time in their lives and at their maturity ages. Another significant group is students with disabilities, for whom virtual
education makes it possible to get training in fields for which it would be more difficult to get in the case of the non-virtual
university. Geographic factors are also relevant, since virtual education has provided rural areas and other places with poor
infrastructures with a chance to gain access to higher education. This brings with it a redistribution of wealth among territories,
and also among different social strata with fewer resources and limitations to commute long distances to higher education
institutions. Another issue that needs pointing out is virtual communication. As it is asynchronic, it can lead to a high
degree of reflection. All these elements enable us to have a virtual discussion about cultural and linguistic issues which
have huge educational value. 相似文献
992.
Hallal PC Reichert FF Ekelund U Dumith SC Menezes AM Victora CG Wells J 《Journal of sports sciences》2012,30(2):183-190
The aim of this study was to investigate the cross-sectional and prospective associations between physical activity and body composition in adolescence. This is a prospective study, including 4,103 adolescents belonging to the Pelotas (Brazil) 1993 birth cohort, who were followed up at the mean ages of 11.3 and 14.7 years. Subsample analyses included 511 individuals with accelerometry and deuterium dilution data at 13.3 years. Sum of skinfolds at age 11.3 years was highly correlated with skinfolds at age 14.7 years (rho = 0.74, P < 0.001). More than 85% of participants remained in the same quintile or changed by not more than one quintile during the 3.4 year period. Tracking of physical activity was considerably lower, although still significant; the correlation was 0.24 (P < 0.001) and 61.4% of the adolescents moved one or less quintiles. In fully-adjusted models, no significant cross-sectional or longitudinal associations were found between physical activity and body composition, neither in boys nor in girls. These null results were confirmed in the 511 individuals with accelerometry and deuterium data. We provide evidence of tracking of physical activity and particularly body composition during adolescence. Our results do not support the hypothesis that physical activity and fatness are strongly related in adolescents. 相似文献
993.
In this study, we examined the relationships between intrinsic motivation, physical self-concept, and satisfaction with life using cross-lagged panel models analysed via structural equation models. The sample consisted of 293 participants (148 men, 145 women) aged 18-70 years who performed diverse types of physical exercise. Three alternative models were tested. The data were better represented by a model in which physical self-concept mediates the relationships between intrinsic motivation and satisfaction with life. Specifically, the direct effects of intrinsic motivation on physical self-concept, and of physical self-concept on satisfaction with life were significant, with the amount of explained variance increasing over time. In conclusion, people who perform physical exercise regularly, and who have fun over time will tend to have a better physical self-perception and, consequently, more psychological well-being. 相似文献
994.
Andrade Mdos S De Lira CA Koffes Fde C Mascarin NC Benedito-Silva AA Da Silva AC 《Journal of sports sciences》2012,30(6):547-553
The purpose of this study was to determine differences in hamstrings-to-quadriceps (H/Q) peak torque ratios evaluated at different angular velocities between men and women who participate in judo, handball or soccer. A total of 166 athletes, including 58 judokas (26 females and 32 males), 39 handball players (22 females and 17 males), and 69 soccer players (17 females and 52 males), were evaluated using an isokinetic dynamometer. The H/Q isokinetic peak torque ratios were calculated at angular velocities of 1.05 rad · s?1 and 5.23 rad · s?1. In the analysis by gender, female soccer players produced lower H/Q peak torque ratios at 1.05 rad · s?1 than males involved in the same sport. However, when H/Q peak torque ratio was assessed at 5.23 rad · s?1, there were no significant differences between the sexes. In the analysis by sport, there were no differences among females at 1.05 rad · s?1. In contrast, male soccer players had significantly higher H/Q peak torque ratios than judokas (66 ± 12% vs. 57 ± 14%, respectively). Female handball players produced significantly lower peak torque ratios at 5.23 rad · s?1 than judokas or soccer players, whereas males presented no ratio differences among sports At 5.23 rad · s?1. In the analysis by velocity, women's muscular ratios assessed at 1.05 rad · s?1 were significantly lower than at 5.23 rad · s?1 for all sports; among men, only judokas presented lower ratios at 1.05 rad · s?1 than at 5.23 rad · s?1. The present results suggest that sport modality and angular velocity influence the isokinetic strength profiles of men and women. 相似文献
995.
Azevedo AP Brandina K Bianco R Oliveira VH Souza JR Mezencio B Amadio AC Serrão JC 《Journal of sports sciences》2012,30(9):929-935
Twelve participants ran (9 km · h(-1)) to test two types of running shoes: replica and original shoes. Ground reaction force, plantar pressure and electromyographic activity were recorded. The shoes were tested randomly and on different days. Comparisons between the two experimental conditions were made by analysis of variance (ANOVA) test (P ≤ 0.05). The time to first peak, loading rate of the first peak and impulse of the first 75 ms of stance were significantly different between the shoes (P ≤ 0.05), revealing an increase of impact forces for the replica shoes. The peak plantar pressure values were significantly higher (P ≤ 0.05) when wearing replica shoes. During running, the contact area was significantly smaller (P ≤ 0.05) for the replica shoe. The electromyographic activity of the analysed muscles did not show changes between the two shoes in running. These findings suggest that the use of replica running shoes can increase the external load applied to the human body, but may not change the muscle activity pattern during locomotion. This new mechanical situation may increase the risk of injuries in these movements. 相似文献
996.
The authors examined how motivational and cognitive variables predict reading comprehension, and whether each predictor variable
adds unique explanatory power when statistically controlling for the others. Fourth-grade students (N = 205) completed measures of reading comprehension in September and December of the same year, and measures of background
knowledge and cognitive strategy use in December. Teachers rated internal reading motivation of each student. Results from
multiple regression analyses showed that motivation, background knowledge, and cognitive strategy-use made significant, independent
contributions to children’s reading comprehension when the other predictor variables were controlled. Further analyses showed
the same cognitive and motivational variables predicted growth over a 3-month period in reading comprehension. Possible explanations
of the observed relations between motivation, cognitive variables, and reading comprehension are presented. 相似文献
997.
This paper reports results obtained in pedagogical interventions in a Brazilian public high school which aimed at promoting a dialogue between scientific and traditional knowledge in the context of biology teaching. The interventions were based on the use of a didactic material and teaching sequence elaborated on the grounds of school knowledge about botany, as presented in biology textbooks, and interviews with students who were also farmers, so as to gather data about their ethnobiological knowledge. Our goal was to develop and test resources that can offer support for teachers who wish to build a dialogue between different ways of knowing in multicultural settings. Our results indicate that the use of the didactic material and teaching sequence indeed created possibilities for a dialogue between the students’ ethnobiological knowledge and biology school knowledge. We observed some shortcomings in classroom practice, partly reflecting our very choice of subject matter to develop the teaching sequence. But the interventions also revealed important limitations that we regard as representative of problems that may generally make multicultural science teaching a hard goal to achieve. It was clear that important shortcomings were related to teachers’ difficulties to conduct a dialogue between ways of knowing in a science classroom, and, thus, called attention to the importance of introducing a multicultural dimension into teacher education. We also observed that the fact that students did not show much sensitivity towards dealing with cultural diversity was a factor constraining the success of the interventions. These results highlight the importance of proposing and testing teacher education initiatives aiming at preparing them to teach science in a culturally sensitive manner, and also managing classroom tensions and conflicts so as to make it possible an effective dialogue between different ways of knowing in a multicultural setting. 相似文献
998.
Antonio Gómez-Bolea Esteve Llop Xavier Ariño Cesareo Saiz-Jimenez Alessandra Bonazza Palmira Messina Cristina Sabbioni 《Journal of Cultural Heritage》2012,13(3):254-258
Several climate parameters affect the growth of organisms and, hence, their capacity to accumulate biomass. In the present research, we analyse the influence of two parameters, temperature and precipitation, on biomass accumulation on stone substrate, and propose a function to estimate it in temperate areas. The expression is subsequently used for the first time to evaluate the impact that climate change would have in biomass accumulation in Europe. The models on climate change predict an increase in temperature and precipitation in northern areas of Europe for the far future (2070–2099), which would lead to a higher accumulation of biomass. Otherwise, a significant reduction in precipitation is expected in southern areas of Europe, associated with a lower biomass accumulation in such areas. 相似文献
999.
Patricia S. Guiamet Vilma Rosato Sandra Gómez de Saravia Ana M. García Diego A. Moreno 《Journal of Cultural Heritage》2012,13(3):339-344
Cemeteries are part of the cultural heritage of urban communities, containing funerary crypts and monuments of historical and architectural interest. Efforts aimed at the conservation of these structures must target not only the abiotic stresses that cause their destruction, such as light and humidity, but also biofouling by biotic agents. The purpose of this study was to assess the development of biofouling of several historically and architecturally valuable crypts at La Plata Cemetery (Argentina). Samples obtained from the biofilms, lichens, and fungal colonies that had developed on the marble surfaces and cement mortar of these crypts were analyzed by conventional microbiological techniques and by scanning electron microscopy. The lichens were identified as Caloplaca austrocitrina, Lecanora albescens, Xanthoparmelia farinosa and Xanthoria candelaria, the fungi as Aspergillus sp., Penicillium sp., Fusarium sp., Candida sp. and Rhodotorula sp., and the bacteria as Bacillus sp. and Pseudomonas sp. The mechanisms by which these microorganisms cause the aesthetic and biochemical deterioration of the crypts are discussed. 相似文献
1000.
José Ignacio Rojas-Sola Miguel Castro-García María del Pilar Carranza-Cañadas 《Journal of Cultural Heritage》2012,13(3):285-292
This article presents new research, which has the objective of quantifying the knowledge produced by historical technological innovations in the field of olive oil industrial heritage. It studies inventions related to the mechanical processes of the extraction of olive oil between 1826 and 1966, which are recorded in the Historical Archive of the Spanish Patent and Trademark Office. It uses a new adaptation of the methodology of knowledge management (KM) defined by Nonaka and Takeuchi. We have obtained the knowledge value of each innovation according to the level of technological knowledge registered at the time, while distinguishing between the historical evolution of inventions relating to milling and those relating to pressing. In the first analysis, the results show a recession in the quantitative level of knowledge in the olive oil sector with respect to the technological potential of the time. However, when contrasted with the events relating to industrial heritage at the time, it is possible to account for this technological evolution and prove the validity of the methodology used. The results show that general evolution of the knowledge generated has decreased, particularly in the pressing process, although this is not the case in the milling process. 相似文献