12,820 research outputs found
Influence of sports satisfaction and interest on a physical fitness program of students in ESO
[Resumen] El objetivo del estudio es comprobar la influencia de la satisfacción deportiva y el interés deportivo en la mejora de 3 pruebas físicas (salto vertical con impulso, salto horizontal a pies juntos y lanzamiento de balón medicinal, estas dos últimas desde parado) a partir de un pre-test y un pos-test en un grupo experimental (n=81) y un grupo control (n=79) tras un programa de entrenamiento de condición física de fuerza, en función del sexo (M=82; F=78) y del curso (1º de Enseñanza Secundaria Obligatoria -ESO- = 60; 2º ESO=51; 3º ESO= 49) en un centro escolar. La frecuencia del entrenamiento fue de 1 día/semana de aproximadamente 1 hora/sesión. Mediante ANOVA de medidas repetidas aplicando el post-hoc de Tukey hemos respondido a las hipótesis planteadas, concluyendo que los alumnos con menos satisfacción e interés con la práctica deportiva son los que más mejoran el rendimiento. No se ha encontrado que un determinado nivel de satisfacción e interés deportivos mejore significativamente la fuerza (p>0.05) en los alumnos del grupo experimental respecto a otros con distintos niveles de satisfacción e interés deportivo del grupo control.[Abstract] The objective of the study is to verify the influence of sports satisfaction and sports interest in
the improvement of 3 physical tests (vertical jump with impulse, horizontal jump to feet
together and throwing of medical ball, these last two from stopped) from a pre-test and posttest
in an experimental group (n=81) and a control group (n=79) after a strength training
program, according to sex (M=82, F=78) and of the course (1st Education Obligatory Secondary
–ESO- = 60; 2nd ESO=51; 3rd ESO=49) in a school. The training frequency was 1 day/week of
approximately 1 hour/session. Through ANOVA of repeated measures applying the post-hoc
of Tukey we have responded to the hypotheses raised, concluding that the students with less
satisfaction and interest with the sport practice are the ones that improve the performance. It
was not found that a certain level of sports satisfaction and interest significantly improved the
strength (p>0.05) in the students of the experimental group compared to others with different
levels of satisfaction and sports interest of the control grou
All-optical radiofrequency modulation of Anderson-localized modes
All-optical modulation of light relies on exploiting intrinsic material
nonlinearities. However, this optical control is rather challenging due to the
weak dependence of the refractive index and absorption coefficients on the
concentration of free carriers in standard semiconductors. To overcome this
limitation, resonant structures with high spatial and spectral confinement are
carefully designed to enhance the stored electromagnetic energy, thereby
requiring lower excitation power to achieve significant nonlinear effects.
Small mode-volume and high quality (Q)-factor cavities also offer an efficient
coherent control of the light field and the targeted optical properties. Here,
we report on optical resonances reaching Q - 10^5 induced by disorder on novel
photonic/phononic crystal waveguides. At relatively low excitation powers
(below 1 mW), these cavities exhibit nonlinear effects leading to periodic (up
to - 35 MHz) oscillations of their resonant wavelength. Our system represents a
test-bed to study the interplay between structural complexity and material
nonlinearities and their impact on localization phenomena and introduces a
novel functionality to the toolset of disordered photonics
Abiotic Input of Fixed Nitrogen by Bolide Impacts to Gale Crater During the Hesperian: Insights From the Mars Science Laboratory
Molecular hydrogen (H2) from volcanic emissions is suggested to warm the Martian surface
when carbon dioxide (CO2) levels dropped from the Noachian (4100 to 3700 Myr) to the Hesperian (3700
to 3000 Myr). Its presence is expected to shift the conversion of molecular nitrogen (N2) into different forms
of fixed nitrogen (N). Here we present experimental data and theoretical calculations that investigate the
efficiency of nitrogen fixation by bolide impacts in CO2‐N2 atmospheres with or without H2. Surprisingly,
nitric oxide (NO) was produced more efficiently in 20% H2 in spite of being a reducing agent and not likely to
increase the rate of nitrogen oxidation. Nevertheless, its presence led to a faster cooling of the shock wave
raising the freeze‐out temperature of NO resulting in an enhanced yield. We estimate that the nitrogen
fixation rate by bolide impacts varied from 7 × 10−4 to 2 × 10−3 g N·Myr−1·cm−2 and could imply fluvial
concentration to explain the nitrogen (1.4 ± 0.7 g N·Myr−1·cm−2) detected as nitrite (NO2
−) and nitrate
(NO3
−) by Curiosity at Yellowknife Bay. One possible explanation is that the nitrogen detected in the
lacustrine sediments at Gale was deposited entirely on the crater's surface and was subsequently dissolved
and transported by superficial and ground waters to the lake during favorable wet climatic conditions. The
nitrogen content sharply decreases in younger sediments of the Murray formation suggesting a decline of H2
in the atmosphere and the rise of oxidizing conditions causing a shortage in the supply to putative
microbial life.We acknowledge the NASA Mars
Science Laboratory Program, Centre
National d'Études Spatiales, the
Universidad Nacional Autónoma de
México (PAPIIT IN109416, IN111619,
and PAPIME PE103216), and the
Consejo Nacional de Ciencia y
Tecnología de México (CONACyT
220626) for their support
Reporte de los hechos ocurridos el 7 de febrero de 2003, atentado Club El Nogal
El presente escrito tiene como fin realizar un análisis detallado de lo sistemas de seguridad que presentaba a la fecha del 7 de Febrero de 2003 el Club el Nogal, esto con el fin de visualizar de manera académica todas aquellas falencias que facilitaron el actuar de grupos subversivos y así perpetrar el acto terrorista (carro bomba) que marco a la sociedad y dejo un precedente de violencia en la capital del país. Para efectos y desarrollo de dicho análisis se enfocara en los aspectos de violencia de la época, situación político-económica del año 2003, y todos aquellos aspectos de seguridad con los que contaba el Club el Nogal a la fecha
La Universidad Accesible, la Universidad de Todos: políticas de adaptación y mejoras docentes para la inclusión de las personas con discapacidad
Se expone qué se define como Universidad Accesible y la importancia que adquiere disponer de una Universidad Accesible para garantizar la inclusión de las personas con discapacidad. Para ello se analizan las condiciones que precisa la accesibilidad en la universidad, los parámetros que debe cumplir y los aspectos que se deben considerar para su aplicación en los campus, tecnologías y servicios universitarios. Se pretende reflexionar sobre la situación actual en lo que se refiere al cumplimiento de los requisitos de Accesibilidad y Diseño para Todos, así como las necesidades de adaptación que requiere, tratando los aspectos propios de la docencia y la investigación, los arquitectónicos y los que afectan a las tecnología de la información. Por último se reflexiona sobre la situación actual y se identifican retos de futuro que permitirán garantizar una universidad accesible
Hierarchical Cluster Analysis of Tourism for Mexico and the Asia-Pacific Economic Cooperation (APEC) Countries
O turismo se tornou um setor de grande importância para a maioria das economias, especialmente aquelas não-industrializadas, caso em que o turismo representa a maior fonte de renda. O artigo centra-se na análise de quatorze fatores de competitividade em 20 países membros da Asia-Pacific Economic Cooperationco (APEC), região mais dinâmica do mundo considerandosua participação no PIB mundial e no comércio internacional, apresentandoa comparação do desempenho do México com outros países da APEC. São analisados dados secundários obtidos do Índice de Competitividade de Viagens & Turismo para criar clusters e, em seguida, são aplicadas técnicas de escalonamento multidimensional para detectar as determinantes mais e menos eficazes na competitividade dos destinos turísticos.El Turismo se ha convertido en un sector de gran importancia para la mayoría de las economías, especialmente para aquellas no industrializadas, caso en que el turismo representa la mayor fuente de renta. El artículo se centra en la análisis de 14 factores de la competitividad para 20 países miembros de la Asia-Pacific Economic Cooperation (APEC), la región más dinámica del mundo considerandosu participación en el PIB mundial y en el comercio internacional, presentando la comparación del desempeño del México con el resto de los países de APEC. Sonanalizados datos secundarios obtenidos del Índice de Competitividad de Viajes y Turismo para crear clusters y posteriormente son aplicadas técnicas de escalamiento multidimensional para detectar los determinantes más y menos eficaces en la competitividad de los destinos turísticos.Tourism has become an important industry for most of the economies, especially for non industrialized countries where it represent the main source of income. This paper focuses on the analysis of 14 competitiveness tourism factors for 20 country members of the Asia-Pacific Economic Cooperation (APEC) forum, which represents the most dynamic region in the world according to its participation on the global GDP and international trade, highlighting the performance of Mexico and doing a benchmark with the rest of APEC countries. The authors analyze secondary data from the Travel and Tourism Competitiveness Index to create clusters and then multidimensional scaling techniques were employed for detecting the more or less effective determinants of destination competitiveness
Analysis of isotopes of plutonium in water samples with a PSresin based on aliquat⋅336
There is a necessity to have techniques capable to perform rapid determinations of specific radionuclides with the aim to provide fast response in emergency situations where a large number of samples need to be measured in a short time. Plastic Scintillation Resins (PSresins) raises as an adequate tool to achieve this purpose and in the present study a methodology to determine plutonium using a PSresin based on Aliquat·336 was developed. Different sample treatments have been studied under acidic conditions with an emphasis on valence adjustment treatment to achieve an effective retention within the PSresin. Under 3 M nitric acid conditions and an iron sulphamate (II) + nitrite valence adjustment, quantitative retention and 100% detection efficiency were achieved. The retention of the different interferences evaluated (238U, 230Th, 241Am, 210Pb and 99Tc) was low and therefore they do not interfere significantly in the determination of plutonium, except for 99Tc. Finally, a stable tracer to calculate the PSresin separation yield was studied, revealing that gold is suitable for this purpose. This procedure was applied to the analysis of spiked sea and river water samples, obtaining errors lower than 10% in their quantification
Sustitución del maíz (Zea mays) por pijuayo (Bactris gasipaes) en alimentación de sajinos (Pecari tajacu)
La presente investigación tuvo como objetivo general evaluar la sustitución del maíz por pijuayo en alimentación de pecarí. Fue realizada en el 2008 en el Centro Piloto de Zoocría para la Amazonía – UNAP, Loreto-Perú. El estudio fue de tipo experimental aplicándose el diseño completamente al azar (DCA), con cuatro tratamientos, tres repeticiones y con tres niveles de inclusión de harina de pijuayo (T1 = 50 %, T2 = 75 %, T3 = 100 %), en todas las dietas elaboradas se realizó previamente el análisis bromatológico. Las unidades experimentales fueron doce (dos individuos por unidad experimental), la alimentación se realizó desde el destete hasta los seis meses de edad, con una frecuencia de dos veces por día durante cuatro meses. Los resultados obtenidos se resumen en que el tratamiento dos (T2) obtuvo una mayor ganancia de peso (9,30 kg), mejor tasa de conversión alimenticia (5,03:1), así como el menor costo de alimento/ kilo de carne de pecarí producido a S/.5, 33 nuevos soles (1dolar USA ≈ 3.65 S/.), en relación al testigo y los demás tratamientos, por lo que este es un excelente alimento compuesto para los pecarís en cautiverio que produciría una mejor carne y piel que traería beneficios económicos al país en general.The general objective of the present investigation was to evaluate the substitution of corn for peccary in peccary feeding. It was carried out in 2008 at the Pilot Center of Zoocría for the Amazon - UNAP, Loreto-Peru. The study was experimental, applying the completely randomized design (DCA), with four treatments, three repetitions and with three levels of inclusion of pijuayo flour (T1 = 50%, T2 = 75%, T3 = 100%), in All the diets prepared, the bromatological analysis was previously carried out. The experimental units were twelve (two individuals per experimental unit), feeding was carried out from weaning to six months of age, with a frequency of twice a day for four months. The results obtained are summarized in that treatment two (T2) obtained a greater weight gain (9.30 kg), a better feed conversion rate (5.03: 1), as well as the lowest cost of feed / kilo of meat of peccary produced at S / .5, 33 nuevos soles (1 US dollar ≈ 3.65 S /.), in relation to the control and the other treatments, so this is an excellent compound food for peccaries in captivity that would produce better meat and skin that would bring economic benefits to the country in general.O objetivo geral do presente trabalho foi avaliar a substituição do milho por caititu na alimentação de caititu. Foi realizado em 2008 no Centro Piloto de Zoocría para a Amazônia - UNAP, Loreto-Peru. O estudo foi experimental, aplicando-se o delineamento inteiramente casualizado (DCA), com quatro tratamentos, três repetições e três níveis de inclusão de farinha de pijuayo (T1 = 50%, T2 = 75%, T3 = 100%), em Todas as dietas preparadas, a análise bromatológica foi realizada previamente. As unidades experimentais foram doze (dois indivíduos por unidade experimental), a alimentação foi realizada da desmama aos seis meses de idade, com frequência de duas vezes ao dia durante quatro meses. Os resultados obtidos resumem-se em que o tratamento dois (T2) obteve um maior ganho de peso (9,30 kg), uma melhor taxa de conversão alimentar (5,03: 1), bem como o menor custo de ração / quilo de carne. de queixadas produzidas a S / .5, 33 nuevos soles (1 dólar norte-americano S 3,65 S /.), em relação ao controle e aos demais tratamentos, portanto, este é um excelente alimento composto para catetos em cativeiro que produziria melhor carne e pele que traria benefícios econômicos ao país em geral
Mechanical oscillations in lasing microspheres
We investigate the feasibility of activating coherent mechanical oscillations
in lasing microspheres by modulating the laser emission at a mechanical
eigenfrequency. To this aim, 1.5% Nd3+:Barium-Titanium-Silicate microspheres
with diameters around 50 {\mu}m were used as high quality factor (Q>10^6)
whispering gallery mode lasing cavities. We have implemented a pump-and-probe
technique in which the pump laser used to excite the Nd3+ ions is focused on a
single microsphere with a microscope objective and a probe laser excites a
specific optical mode with the evanescent field of a tapered fibre. The studied
microspheres show monomode and multi-mode lasing action, which can be modulated
in the best case up to 10 MHz. We have optically transduced thermally-activated
mechanical eigenmodes appearing in the 50-70 MHz range, the frequency of which
decreases with increasing the size of the microspheres. In a pump-and-probe
configuration we observed modulation of the probe signal up to the maximum pump
modulation frequency of our experimental setup, i.e., 20 MHz. This modulation
decreases with frequency and is unrelated to lasing emission, pump scattering
or thermal effects. We associate this effect to free-carrier-dispersion induced
by multiphoton pump light absorption. On the other hand, we conclude that, in
our current experimental conditions, it was not possible to resonantly excite
the mechanical modes. Finally, we discuss on how to overcome these limitations
by increasing the modulation frequency of the lasing emission and decreasing
the frequency of the mechanical eigenmodes displaying a strong degree of
optomechanical coupling.Comment: 17 pages, 5 figure
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