Costa Rica: A national educational development plan     

Uladislao Gámez Solano  Carlos E. Olivera 《Prospects》1974,4(4):503-511

  相似文献   

Incidence and risk for traumatic and overuse injuries in top-level road cyclists     

De Bernardo N  Barrios C  Vera P  Laíz C  Hadala M 《Journal of sports sciences》2012,30(10):1047-1053

All traumatic and overuse injuries occurring during an average period of 4 years (2002/09) in a group of 51 currently active road top-level cyclists were retrospectively registered through clinical interviews. Average age was 25.8 years. Average training and competition period was 28.3 ± 2.4 h a week. Only 8 cyclists (15.6%) were completely free from lesions during the period of study. The remaining 43 cyclists suffered a total of 112 lesions; however, 9 out of these were unrelated to their cycling practice. These 103 cycling-related injuries include 50 (48.5%) traumatic and 53 (51.5%) overuse injuries. Twenty-eight fractures were reported, the clavicle being the most frequently affected bone (11 cases). The 68.5% of overuse injuries were located in the lower limbs. Most overuse injuries (89.6%) occurred during the training period. According to the injury abbreviated scale (AIS), severe lesions were only found in 4 cases (8% of traumatic injuries). Overall injury rates were 0.50 per racer/year, 2.02 per studied racer, and 0.007 per 1000 km of training and competition. Active professional top-level cyclists are exposed to a high injury risk. According to the scarce previously published data the current study provides relevant information on the injury occurrence of still active top-level road cycling.  相似文献   

Influence of regression model and incremental test protocol on the relationship between lactate threshold using the maximal-deviation method and performance in female runners     

Machado FA  Nakamura FY  Moraes SM 《Journal of sports sciences》2012,30(12):1267-1274

This study examined the influence of the regression model and initial intensity of an incremental test on the relationship between the lactate threshold estimated by the maximal-deviation method and the endurance performance. Sixteen non-competitive, recreational female runners performed a discontinuous incremental treadmill test. The initial speed was set at 7 km · h?1, and increased every 3 min by 1 km · h?1 with a 30-s rest between the stages used for earlobe capillary blood sample collection. Lactate-speed data were fitted by an exponential-plus-constant and a third-order polynomial equation. The lactate threshold was determined for both regression equations, using all the coordinates, excluding the first and excluding the first and second initial points. Mean speed of a 10-km road race was the performance index (3.04 ± 0.22 m · s?1). The exponentially-derived lactate threshold had a higher correlation (0.98 ≤ r ≤ 0.99) and smaller standard error of estimate (SEE) (0.04 ≤ SEE ≤ 0.05 m · s?1) with performance than the polynomially-derived equivalent (0.83 ≤ r ≤ 0.89; 0.10 ≤ SEE ≤ 0.13 m · s?1). The exponential lactate threshold was greater than the polynomial equivalent (P < 0.05). The results suggest that the exponential lactate threshold is a valid performance index that is independent of the initial intensity of the incremental test and better than the polynomial equivalent.  相似文献   

Creatine kinase activity weakly correlates to volume completed following upper body resistance exercise     

Machado M  Willardson JM  Silva DR  Frigulha IC  Koch AJ  Souza SC 《Research quarterly for exercise and sport》2012,83(2):276-281

In the current study, we examined the relationship between serum creatine kinase (CK) activity following upper body resistance exercise with a 1- or 3-min rest between sets. Twenty men performed two sessions, each consisting of four sets with a 10-repetition maximum load. The results demonstrated significantly greater volume for the 3-min condition (M = 4156 kg, SD = 867, for 3 min; vs. M = 3503 kg SD = 759, for 1 min; p < .001), with no significant differences in delta CK activity between conditions (p = .574). Nevertheless, there was a weak correlation between the delta CK activity and total volume of exercise completed (r = .55 with a 1-min rest, and r = .45 with a 3-min rest). Therefore, the volume following upper body resistance exercise correlates weakly with serum CK levels, irrespective of rest interval length between sets.  相似文献   

Emergent relations in pigeons following training with temporal samples     

Edson M. Huziwara  Saulo M. Velasco  Gerson Y. Tomanari  Deisy G. de Souza  Armando D. Machado 《Learning & behavior》2013,41(2):192-204

In two experiments, we investigated emergent conditional relations in pigeons using a symbolic matching-to-sample task with temporal stimuli as the samples and hues as the comparisons. Both experiments comprised three phases. In Phase I, pigeons learned to choose a red keylight (R) but not a green keylight (G) after a 1-s signal. They also learned to choose G but not R after a 4-s signal. In Phase II, correct responding consisted of choosing a blue keylight (B) after a 4-s signal and a yellow keylight (Y) after a 16-s signal. Comparisons G and B were both related to the same 4-s sample, whereas comparisons R and Y had no common sample. In Phase III, R and G were presented as samples, and B and Y were presented as the comparisons. The choice of B was correct following G, and the choice of Y was correct following R. If a relation between comparisons that shared a common sample were to emerge, then responding to B given G would be more likely than responding to Y given R. The results were generally consistent with this prediction, suggesting, for the first time in pigeons, the emergence of novel relations that involve temporal stimuli as nodal samples.  相似文献   

El aprendizaje de las matemáticas elementales como proceso condicionado por la cultura     

Carlos Vasco 《Cultura y Educación》2013,25(6):5-26

En «El aprendizaje de las matemáticas elementales como proceso condicionado por la cultura», Carlos Vasco examina el «mito» de que las matemáticas son un «lenguaje universal de la ciencia» y, por tanto, una materia supracultural. En sus análisis de casos de niños colombianos, llega a la conclusión de que las matemáticas pueden depender tanto de la cultura como el aprendizaje de la literatura o la historia. Según Vasco, la mayoría de los enseñantes cree que los niños no saben nada de matemáticas cuando entran en la escuela; por tanto, la enseñanza de la «matemática moderna» sólo puede llegar a un pequeño porcentaje de los niños. Vasco aduce que sólo los estudiantes que pueden construir sus propios «sistemas conceptuales a pesar de sus maestros» y desentrañar por su cuenta la maraña de sistemas simbólicos serán inmunes a la «fobia a las matemáticas».  相似文献   

How Exactly Does Place Matter in Crime Analysis? Place,Space, and Spatial Heterogeneity     

Carlos J. Vilalta 《Journal of Criminal Justice Education》2013,24(3):290-315

This article has four aims. First is to clarify the origins and different meanings of place, space, and other basic concepts in spatial analysis. The second aim is to reiterate the illogicality of the spatial homogeneity assumption in ordinary least squares (OLS) regression. An illustration of the comparison between traditional OLS and geographically weighted regression modeling is included for this purpose. The third aim is to explain that place matters in crime analysis not only when crime data are spatially clustered, but when relationships between correlates are found to be conditional upon place. The final aim is to convince criminology and criminal justice faculty to begin discussing the inclusion of spatial modeling as a compulsory topic in the curriculum.  相似文献   

Factor Analysis with Ordinal Indicators: A Monte Carlo Study Comparing DWLS and ULS Estimation     

Carlos G. Forero  Alberto Maydeu-Olivares  David Gallardo-Pujol 《Structural equation modeling》2013,20(4):625-641

Factor analysis models with ordinal indicators are often estimated using a 3-stage procedure where the last stage involves obtaining parameter estimates by least squares from the sample polychoric correlations. A simulation study involving 324 conditions (1,000 replications per condition) was performed to compare the performance of diagonally weighted least squares (DWLS) and unweighted least squares (ULS) in the procedure's third stage. Overall, both methods provided accurate and similar results. However, ULS was found to provide more accurate and less variable parameter estimates, as well as more precise standard errors and better coverage rates. Nevertheless, convergence rates for DWLS are higher. Our recommendation is therefore to use ULS, and, in the case of nonconvergence, to use DWLS, as this method might converge when ULS does not.  相似文献   

Fibre Optic Reflectance Spectroscopy as a non-invasive tool for investigating plastics degradation in contemporary art collections: A methodological study on an expanded polystyrene artwork     

Costanza Cucci  Leonardo Bigazzi  Marcello Picollo 《Journal of Cultural Heritage》2013,14(4):290-296

Fibre Optics Reflectance Spectroscopy (FORS) is a well-established technique, widely used in the conservation field for in situ investigations and non-invasive diagnostics on traditional artworks. Nevertheless, there is little knowledge on the use of this technique for investigating modern artists materials used in contemporary artworks. The present study, carried out within the wider framework of the EC funded Project “POPART” (Preservation of Plastic ARTefacts in museum collections”), was aimed at investigating the possibility of extending the applications of FORS to synthetic polymers, and proposing this technique as new non-invasive analytical tool for diagnostics on plastic artworks in museum collections. Thus, a real case was selected from the permanent collection of the Conteporary Art Centre “Luigi Pecci” (Prato, Italy). The artwork, created in 1990 by the artist Stefano Arienti, was entirely constituted of expanded polystyrene (EPS) and it showed diffused signs of degradation. The need of singling out the main causes of deterioration in order to prevent further damages was evident. An in situ FORS measurements campaign was performed with the aim of gaining in-depth information about its conservation state and identifying the main agents responsible for the observed degradation. Thanks to the non-invasivity of the technique an extensive spectroscopic characterisation of different areas of the EPS surface could be performed and the spectral data were exploited to build a map of the degraded areas of the artwork. Data acquired in field were compared with those obtained from laboratory test performed on artificially aged EPS samples. These results helped in ascertaining the detrimental actions of the light sources used to back illuminate the artwork. In particular, in this case FORS proved to be effective in detecting EPS alterations before the chromatic effects became visually evident. These results suggested that FORS may be considered as a good candidate to be used for non-invasive investigations also on some modern materials and contemporary artworks. The research was completed with an interview to the artist Stefano Arienti, whose point of view was constructively integrated with the scientific results obtained. This emphasized the importance of an interdisciplinary approach to the solution of conservative problem in the field of contemporary art.  相似文献   

Promoting a participatory convergence in a Spanish context: an inter-university action research project using visual narrative     

Elia Fernández-Díaz  Carlos Rodríguez-Hoyos  Adelina Calvo Salvador  Gloria Braga Blanco  Lorea Fernández-Olaskoaga  Prudencia Gutiérrez-Esteban 《Educational Action Research》2019,27(3):362-378

ABSTRACT

This article focuses on the deconstruction of an inter-university action research project that has allowed us to rethink our teaching and research, questioning the social, political and ethical dimensions of the university. Following the pre-assembly proposal to promote participatory convergence, organized within the framework of the 1^st Global Assembly for Knowledge Democracy (2017), an action research process was implemented in order to generate systematic inquiry around the current situation of the university and the need to act and rethink our commitment to promoting changes in this context. We have reflected on the meaning of democratization, rethinking the pedagogical relationship with our students and how we critically commit them to promote activism. We generated an environment where we look for the meaning of our practices by means of a visual narrative which has enabled us to weave and identify our own biography and become aware of where we are and why we act in one way or another. We have also focused on the search for the meaning of our actions in relation to the community we belong to and how to deal with the challenges of social justice, encouraging collaboration with other networks in a wider inter-university framework.  相似文献