Fluid intake, hydration status and body mass changes in U-15 judo athletes during a training day

[EN] Despite numerous studies related to dehydration there is still a lack of scientific literature presenting hydration status and fluid intake of judo athletes during different periods. Therefore, the aim of this study was to investigate, fluid intake, hydration status and body weight changes o f young judo athletes during a typical day of training in preparation period. Twenty - two young judo athletes (age: 12 ± 0.7 y, experience: 3.5 ± 1.1) voluntarily participated in this study. Hydration status and weight were examined in the morning, before a nd immediately after the training. All athletes trained 90 min and they consumed fluids ad libitum during the exercise. According to morning urine specific gravity (USG) values, 81.2% of the athletes were dehydrated while only 18.8% of the athletes were eu hydrated. Pre - training urine measurements showed that 63.64% of the athletes presented dehydration and 77.27% of the athletes completed the training in dehydrated condition despite fluid availability during the training. Mean body weight loss during traini ng was - 0.64 ± 0.66%. It can be concluded that young judo athletes presented high prevalence of dehydration as indicated by USG values. Most of the athletes were dehydrated during a typical training day and completed the training in more dehydrated conditi ons compared to pre training values despite ad libitum fluid intake. It is of great importance to evaluate hydration status of the athletes before training to refrain from common practice of fluid restriction for weight loss and adverse effects of a persis tent state of fluid deficit on physical and health related state.S

Colloidal Synthesis of Gold Semishells

This work describes a novel and scalable colloid chemistry strategy to fabricate gold semishells based on the selective growth of gold on Janus silica particles (500 nm in diameter) partly functionalized with amino groups. The modulation of the geometry of the Janus silica particles allows us to tune the final morphology of the gold semishells. This method also provides a route to fabricating hollow gold semishells through etching of the silica cores with hydrofluoric acid. The optical properties were characterized by visible near-infrared (vis-NIR) spectroscopy and compared with simulations performed using the boundary element method (BEM). These revealed that the main optical features are located beyond the NIR region because of the large core size

Uso pedagógico del blog: un proyecto de investigación-acción en la materia de Educación Física en Educación Secundaria

[EN] The goal of this projectwas to assess the effects of theuse of ablog as aresourcein Physical Education.108 students of 4thgradeof Secondary Education participated in the project, which lastedacompleteacademic year. Data was collected viaquestionnaire. Semi-structured interviews were also conducted to obtain more information.Results showthe highpedagogical value that students give to these digital tools[ES] El objetivo de este trabajo fue conocer los efectos del uso del blogcomo recurso de apoyo a la materia de Educación Física. 108 estudiantes de 4º de ESO participaron en la experiencia, desarrolladaduranteun curso escolar. Los datos se recogieron mediante un cuestionariodesarrolladoad hoc. También se realizaron entrevistas semi-estructuradas para obtener más información. Los resultados indican elgranvalor pedagógico que los estudiantes dan a estas herramientas digitalesS

A new strategy based on adaptive mixture of Gaussians for real-time moving objects segmentation

Here, a new and efficient strategy is introduced which allows moving objects detection and segmentation in video sequences. Other strategies use the mixture of gaussians to detect static areas and dynamic areas within the images so that moving objects are segmented [1], [2], [3], [4]. For this purpose, all these strategies use a fixed number of gaussians per pixel. Typically, more than two or three gaussians are used to obtain good results when images contain noise and movement not related to objects of interest. Nevertheless, the use of more than one gaussian per pixel involves a high computational cost and, in many cases, it adds no advantages to single gaussian segmentation. This paper proposes a novel automatic moving object segmentation which uses an adaptive variable number of gaussians to reduce the overall computational cost. So, an automatic strategy is applied to each pixel to determine the minimum number of gaussians required for its classification. Taking into account the temporal context that identifies the reference image pixels as background (static) or moving (dynamic), either the full set of gaussians or just one gaussian are used. Pixels classified with the full set are called MGP (Multiple Gaussian Pixel), while those classified with just one gaussian are called SGP (Single Gaussian Pixel). So, a computation reduction is achieved that depends on the size of this last set. Pixels with a dynamic reference are always MGP. They can be Dynamic-MGP (DMGP) when they belong to the dynamic areas of the image. However, if the classification result shows that the pixel matches one of the gaussian set, then the pixel is labeled static and therefore it is called Static-MGP (SMGP). Usually, these last ones are noise pixels, although they could belong to areas with movement not related to objects of interest. Finally, pixels with a static reference that still match the same gaussian are SGP and they belong to the static background of the image. However, if they do not match the associated gaussian, they are changed either to SMGP or DMGP. In addition, any pixel can maintain its status and SMGP can be changed to DMGP and SGP. A state diagram shows the transition schemes and its characterizations, allowing the forecasting of the reduction of the computational cost of the segmentation process. Tests have shown that the use of the proposed strategy implies a limited loss of accuracy in the segmentations obtained, when comparing with other strategies that use a fixed number of gaussians per pixel, while achieving very high reductions of the overall computational cost of the process

Effect of multiple injection strategies on emissions and performance in the Wärtsilä 6L 46 marine engine. A numerical approach

Author manuscript version[Abstract] The present paper proposes a Computational Fluid Dynamics model to analyze the operation cycle and exhaust gas composition in a four-stroke marine diesel engine, the Wärtsilä 6L 46. Once validated, the numerical model was employed to study the influence of several pre-injection parameters such as pre-injection rate, duration, starting instant and number of pre-injections. The purpose is to reduce consumption and emissions, especially nitrogen oxides, due to the current increasingly restrictive legislation. It was found that the fuel injection is a critical factor influencing combustion and emission characteristics. Important nitrogen oxides emission reductions were obtained for the parameters analyzed. Particularly, a 31.9% nitrogen oxides reduction was obtained using 20% pilot injection, 65.7% advancing 4° the pre-injection start angle, 20.1% shorting 4° the pre-injection duration and 36.7% using 4 pre-injections. A slight increment of hydrocarbons, carbon monoxide and consumption was obtained, lower than 5% for almost all the cases analyzed, and a negligible effect on carbon dioxide emissions

The antioxidant effects of soybean lecithin- or low-density lipoprotein-based extenders for the cryopreservation of brown-bear (Ursus arctos) spermatozoa

P. 1185-1193Egg yolk low-density lipoproteins (LDL) and soybean lecithin were evaluated as replacements for egg yolk in extenders used for the cryopreservation of brown-bear spermatozoa. The motility, viability and acrosomal status of post-thawed spermatozoa were analysed, and an egg-yolk extender was used as a control. The total antioxidant capacity of these extenders was tested. Soybean lecithin showed an effect that was dependent on the soybean concentration (2%, 3.5% and 5%) and source (Type A: 24% l-α-phosphatidylcholine, and Type B: 14–23% l-α-phosphatidylcholine). Only semen cryopreserved with 5% Type A soybean exhibited a sperm motility similar to that of semen cryopreserved in egg-yolk-based extender after thawing, although the sperm viability and acrosome status were not as high. Semen frozen in an extender containing LDL (10–15%) exhibited improved sperm viability in comparison with the control, but sperm motility was lower. The LDL-based extender exhibited a higher anti-oxidant activity than the egg-yolk extender and soy lecithin-based extenders. The extenders with higher anti-oxidant activity showed improvements in frozen sperm viability but lower semen motility. These results indicate that soybean lecithin did not have the same protective effect as egg yolk during the freezing of brown-bear spermatozoa but suggest that LDL (10–15%) could be a useful substitute for egg yolk in these extenders

The Effects of COVID-19 Confinement on the Spanish Family: Adaptation or Change?

Spain is one of the countries that has been most affected by the COVID-19 pandemic worldwide. As a southern European country, Spain is characterized by high levels of sociability and the vital role of the family in its social structure. The intense confinement phase raised many questions about how the Spanish family would adapt to this crisis. This study analyzes the consequences of confinement on three areas of family life: the emotional state of its members, family relationships inside and outside the home, and the impact of ICTs on families in isolation. Only statistically representative data published by Spain’s main research institutes are used for this study. The results highlight the important adaptive capacity of the Spanish family, the activation of solidarity networks and the improvement in internal and external family relationships. This situation has served to accelerate the development of new technologies in the domestic sphere, with effects on the communicative relationship between its members and to open the debate on teleworking as a tool for reconciliation of work and family life.This study was supported by the Ministry of Economy and Competitiveness of Spain under project CSO2017-86349-P; Project GESTIM (BBVA Foundation 35/2018), and ERDF Andalusia Programme financed by the European Union: Project #UMA18-FEDERJA-103

El «Cuaderno de Bitácora» de Educación Física. Elemento central dentro de una propuesta de metaevaluación = The Logbook of Physical Education. Key element inside a meta-assessment proposal

P. 92-96El estado actual de conocimientos pedagógicos aplicados a la Educación Física demanda nuevas formas de desarrollar todo el proceso de enseñanza-aprendizaje. Desde nuestro punto de vista, éste debe estar presidido por la claridad y la objetividad, y el alumnado debe ser partícipe de él. Presentamos una propuesta práctica de metaevaluación para la materia de Educación Física dentro de la Educación Secundaria Obligatoria, cuyo eje central denominamos: «Cuaderno de Bitácora». El objetivo de este planteamiento fue convertir al alumnado en gestor de su propio proceso de desarrollo y aprendizaje, incluida la evaluación. A través de este cuaderno, el proceso de enseñanza-aprendizaje «sobrepasa las paredes del aula» para convertirse en una herramienta que el alumnado usa dentro y fuera de la escuela. Las valoraciones efectuadas por el alumnado de la aplicación práctica de esta propuesta han sido muy positivas, ya que da «voz y voto» al verdadero protagonista de todo el proceso educativo: el alumno/aS

Uso pedagógico del blog: un proyecto de investigación-acción en la materia de Educación Física en Educación Secundaria = Pedagogical use of the blog: an action-research project in Physical Education at the Secondary level

14 p.El objetivo de este trabajo fue conocer los efectos del uso del blog como recurso de apoyo a la materia de Educación Física. 108 estudiantes de 4º de ESO participaron en la experiencia, desarrollada durante un curso escolar. Los datos se recogieron mediante un cuestionario desarrollado ad hoc. También se realizaron entrevistas semi-estructuradas para obtener más información. Los resultados indican el gran valor pedagógico que los estudiantes dan a estas herramientas digitalesS