1,565 research outputs found
Factors that influence the process of formation of the olympic judokas
Con el objetivo de analizar los factores que influyen en el proceso de formación deportiva de los judokas españoles olímpicos, se aplicó una entrevista semiestructurada de 52 preguntas agrupadas en 6 dimensiones (Contexto Deportivo, Contexto Social, Proceso de Formación, Psicológica, Técnico-táctica, Condición Física). Los resultados muestran que los judokas olímpicos se iniciaron en la práctica del Judo a los 6,90 ± 3,02 años, concretamente las mujeres a los 6,80 ± 2,88 años y los hombres algo más tarde, a los 7 ± 3,42 años, el 95% (n=19) influenciados, fundamentalmente, por un familiar. Además, destaca que ninguno de los entrevistados consiguió medalla en categorías inferiores. Para el 75% (n=15) de los judokas olímpicos es muy importante llevar una sincronización del entrenamiento técnico-táctico, de la condición física y de los aspectos psicológicos de forma integradaWith the aim of analizing the factors that have an influence on the sports training process of the olympic Spanish judokas, a semistructured interview of 52 questions grouped in 6 aspects was carried out: Sports Context, Social Context, Training Process, Psychological Condition, Technical-Tactical Condition and Physical Conditon). The results show that olympic judokas began practising judo at the age of 6.90 ± 3.02 years. Specifically, women started at the age of 6.80 ± 2.88, and men slightly later, at the age of 7 ± 3.42 years. 95% (n=19) of them were mainly influenced by a relative. Moreover, it is to be highlighted that none of the interviewees won a medal in low categories. For 75% (n=15) of the olympic judokas, it is very important that technical-tactical training, physical condition training and psychological aspects be synchronised in an integrated wa
Heavy metals as an indicator of ecological impact of a fragmented land uses, San Luis Potosi, Mexico
La necesidad de estudiar la presencia
de metales pesados en el suelo radica en su
impacto como indicador de contaminación
ambiental. Se determinó la presencia de Cu,
Zn, Pb y Cd en suelos donde se distribuyen
especies vegetales en un corredor ecológico.
Entre los municipios de Soledad de Graciano
Sánchez y San Luis Potosí (México) fueron
establecidos 30 puntos distribuidos en cinco
prácticas dominantes de usos de suelo:
agropecuario, residencial rural, comercio y
servicios, residencial urbano y minero. Los
muestreos se realizaron en cuatro épocas
durante 2009 y 2010 (verano, otoño, invierno y
primavera). Se encontró un efecto significativo
del uso del suelo en cuanto a los niveles de
Cu (p = 0,000), Pb (p = 0,043) y Cd (p = 0,010).
En el caso del Zn, el uso del suelo (p = 0,000)
y la estación (p = 0,059) fueron significativos.
El uso del suelo minero mostró las mayores
concentraciones de metales y el agrícola las
menores. Los niveles de los cuatro metales se
encuentran en el rango marcado como alto por
la EPA y por otras fuentes técnicas. En el caso
de Pb y Cd no rebasan los estándares NOM-147-
SEMARNAT-SSA1. Estos resultados reflejan
el potencial indicativo del uso del suelo en la
evaluación de la calidad ambiental, sin embargo,
se requiere continuar con un monitoreo de
metales pesados en la zona.The need to study the presence of heavy
metals in the soil lies on their impact as a indicator
of environmental pollution. Therefore, it was
determined the presence of Cu, Zn, Pb and Cd
in soils where plant species were distributed in
an ecological corridor. Among the municipalities
of Soledad Graciano Sanchez and San Luis
Potosi (Mexico), 30 points were established,
distributed in five land uses: agricultural , rural
residential, trade and services, urban residential
and mining. Sampling was conducted from
2009 to 2010 (summer, fall, winter and spring).
A significant effect of land use was found in
terms of Cu (p = 0.000), Pb (p = 0.043) and
Cd (p = 0.010). In the case of Zn both the land
use (p = 0.000) and season (p = 0.059) had
significant effects. It is emphasized that mining
land use presented the highest concentrations
of the studied metals and agricultural land use
the lowest. The levels of four metals are in the
range marked like high by the EPA and other
technical sources. The levels of Pb and Cd do not
exceed the NOM-147-SEMARNAT-SSA1. These
results reflect the indicative potential of the soil
and its consideration for future to evaluate the
habitat of plant species. These results reflect the
potential indicative land use in the assessment
of environmental quality, however, requires
continued monitoring of heavy metals in the area.Fil: Alcalá Jáuregui, Jorge.
Universidad Autónoma de San Luis Potosí. Facultad de AgronomíaFil: Ávila Castorena, Cecilia.
Universidad Autónoma de San Luis Potosí. Facultad de AgronomíaFil: Rodríguez Ortíz, Juan C..
Universidad Autónoma de San Luis Potosí. Facultad de AgronomíaFil: Hernández Montoya, Alejandra.
Universidad Autónoma de San Luis Potosí. Facultad de AgronomíaFil: Beltrán Morales, F. Alfredo.
Universidad Autónoma de Baja California Sur (México)Fil: Rodríguez Fuentes, Humberto.
Universidad Autónoma de Nuevo León (México). Facultad de Agronomía.Fil: Loya Ramírez, J. Guadalupe.
Universidad Autónoma de Baja California Sur (México
Vegetative as bioindicators of heavy metals in a semiarid system
Evaluar la contaminación por metales
pesados en los ecosistemas permite conocer la
capacidad bioindicativa de especies vegetativas.
El objetivo fue determinar la concentración
de metales pesados en Prosopis laevigata,
Acacia spp. y Schinus molle bajo el efecto de
usos suelo y temporalidad. El área se sitúa en
la colindancia de los Municipios de Soledad
de Graciano Sánchez y San Luis Potosí
fragmentada por usos de suelo: agropecuario,
comercio y servicios, residencial urbano y
minero. Fueron tomadas muestras de hojas de
las tres especies en las estaciones de verano,
otoño, invierno y primavera y se evaluó la
concentración de metales pesados a través de
la técnica de ICP-MS. Los análisis estadísticos
indicaron niveles de Aluminio (Al) > Cinc (Zn) >
Plomo (Pb) > Cobre (Cu) > Titanio (Ti) >
Vanadio (V) > Arsénico (As) > Cromo (Cr) >
Cadmio (Cd) > Cobalto (Co). Los elementos
Al, As, Cd, Cr, Pb y Ti presentaron niveles por
encima del umbral normal en vegetación. El
uso de suelo tuvo efecto significativo con Al,
Ti, Cd, As y Pb; los árboles ubicados en los
usos de suelo minero, comercio y servicios
tuvieron la mayor concentración. La especie
tuvo efecto significativo con Al y Pb siendo
Acacia spp. el que presentó la mayor capacidad
de acumulación. La temporada del año impactó
significativamente en la acumulación de As, Cd,
Co, Cu, Cr y Ti en las tres especies. La dinámica
antropogénica de los diferentes usos de suelo
genera partículas y residuos con metales
pesados impactando en la disponibilidad
y acumulación en las especies evaluadas.
Se contribuye a evaluar el impacto ambiental
en el sistema fragmentado recomendando dar
continuidad a este tipo de estudios.The evaluation of pollution by heavy metals
on ecosystems can determine the bioindicative
capacity of plant species. The presence of
heavy metals was determined in Prosopis
laevigata, Acacia spp. and Schinus molle under
the effect of different of land uses and seasons.
The area is located near of the municipalities
of Soledad de Graciano Sánchez and San
Luis Potosi which has fragmented land use
such as: agriculture, commercial and services,
urban residential and mining. Samples were
taken from leaves of the three species during
summer, autumn, winter and spring to assess
the concentrations of heavy metals through
the technique of ICP-MS. Statistical analyzes
showed levels of Aluminum (Al) > Zinc (Zn)
> Lead (Pb) > Copper (Cu) > Titanium (Ti) >
Vanadium (V) > Arsenic (As) > Chromium (Cr)
> Cadmium (Cd) > Cobalt (Co). The elements
Al, As, Cd, Cr, Pb and Ti had levels above the
normal threshold in vegetation. Land use had a
significant effect with Al, Ti, Cd, As and Pb having
the trees being located in the land with mining
and commercial and services use the greater
concentrations. The species had a significant
effect on Al and Pb with Acacia spp., having
the largest storage capacity. The season of the
year significantly impacted the accumulation of
As, Cd, Co, Cu, Cr and Ti in the three species.
The anthropogenic dynamics of different land
uses generated waste particles and residues
of heavy metals, impacting the availability and
accumulation in the species evaluated. This
study contribute to evaluate the environmental
impact in the system with a fragmented land
use and the continuation of this type of studies
is recommended.Fil: Alcalá Jáuregui, Jorge.
Universidad Autónoma de San Luis Potosí. Facultad de AgronomíaFil: Rodríguez Ortíz, Juan C..
Universidad Autónoma de San Luis Potosí. Facultad de AgronomíaFil: Villaseñor Zuñiga, María Elena.
Universidad Autónoma de San Luis Potosí. Facultad de AgronomíaFil: Hernández Montoya, Alejandra.
Universidad Autónoma de San Luis Potosí. Facultad de AgronomíaFil: García Arreola, María Elena.
Universidad Autónoma de San Luis Potosí. Facultad de AgronomíaFil: Beltrán Morales, F. Alfredo.
Universidad Autónoma de Baja California Sur (México)Fil: Rodríguez Fuentes, Humberto.
Universidad Autónoma de Nuevo León (México). Facultad de Agronomía
Recovering long-term aerosol optical depth series (1976–2012) from an astronomical potassium-based resonance scattering spectrometer
A 37-year long-term series of monochromatic aerosol optical depth (AOD) has been recovered from solar irradiance measurements performed with the solar spectrometer Mark-I, deployed at Izaña mountain since 1976. The instrument operation is based on the method of resonant scattering, which affords wavelength absolute reference and stability (long-term stability and high precision) in comparison to other instruments based purely on interference filters. However, it has been specifically designed as a reference instrument for helioseismology, and its ability to determine AOD from transmitted and scattered monochromatic radiation at 769.9 nm inside a potassium vapour cell in the presence of a permanent magnetic field is evaluated in this paper. Particularly, the use of an exposed mirror arrangement to collect sunlight as well as the Sun–laboratory velocity dependence of the scattered component introduces some important inconveniences to overcome when we perform the instrument's calibration. We have solved this problem using a quasi-continuous Langley calibration technique and a refinement procedure to correct for calibration errors as well as for the fictitious diurnal cycle on AOD data. Our results showed similar calibration errors retrieved by means of this quasi-continuous Langley technique applied in different aerosol load events (from 0.04 to 0.3), provided aerosol concentration remains constant throughout the calibration interval.The AERONET sun photometers
at Izaña have been calibrated within AERONET-Europe TNA
supported by the European Community-Research Infrastructure
Action under the FP7 “Capacities” specific programme for
Integrating Activities, ACTRIS grant agreement no. 262254.
The GAW-PFR network for AOD at WMO-GAW global observatories
has been implemented by the World Optical Depth
Research and Calibration Center (WORCC). Mark-I operation
was supported by the Spanish National Plan of Research and
Development under grant no. AYA2012–17803
A New Methodology to Simulate Three-Dimensional Hydraulic Loads on a Vertical Breakwater along its Life Cycle
This work has been part of the research project DOVICAIM (RTC-2014-3077-4), which was financially supported by the Spanish Ministry of Economy, Industry and Competitiveness (MINECO) within the National Program for Research Aimed at the Challenges of Society
Implementing Pairings at the 192-bit Security Level
We implement asymmetric pairings derived from Kachisa-Schaefer-Scott (KSS), Barreto-Naehrig (BN), and Barreto-Lynn-Scott (BLS) elliptic curves at the 192-bit security level. Somewhat surprisingly, we find pairings derived from BLS curves with embedding degree 12 to be the fastest for our serial as well as our parallel implementations. Our serial implementations provide a factor-3 speedup over the previous state-of-the-art, demonstrating that pairing computation at the 192-bit security level is not as expensive as previously thought. We also present a general framework for deriving a Weil-type pairing that is well-suited for computing a single pairing on a multi-processor machine
Climatic change and species modeling of Stevia (Asteraceae) in northwestern Argentina
La elevada biodiversidad y riqueza específica, junto con una gran variedad de ecosistemas, convierten al noroeste de la Argentina (NOA) en un área adecuada para estudiar los posibles efectos del cambio climático sobre la distribución de los organismos. Asteraceae es una familia de plantas con flores bien representada en esta área; en especial, el género Stevia, con 25 especies que habitan diferentes ambientes. Los objetivos de este estudio fueron: 1) modelar la aptitud de hábitat para cinco especies de Stevia que habitan el noroeste argentino, y 2) proyectar dicha aptitud bajo un posible escenario de emisión de gases de efecto invernadero para el año 2050. Se analizaron las especies S. alpina, S. breviaristata, S. minor, S. vaga y S. yaconensis. Los resultados mostraron que, al comparar los mapas basados en condiciones climáticas actuales y futuras, todas las especies de Stevia sufrirían modificaciones en sus rangos de aptitud. Las tendencias observadas en ambos escenarios climáticos futuros son similares, aunque más drásticas en el modelo rcp8.5. El área de aptitud de Stevia alpina, S. breviaristata y S. minor se vería reducida, mientras que la de S. vaga y S. yaconensis aumentaría. Excepto S. minor, las especies presentaron una tendencia principal a migrar del este al oeste, un fenómeno conocido como desplazamiento en altura. Stevia minor sería la especie más afectada en un escenario de mayor emisión de gases; sufriría una reducción mayor a 80% para valores de aptitud superiores a 0.65.The high biodiversity and species richness, along with a great variety of ecosystems, turn northwestern Argentina into an adequate area for study the possible effects of climate change on the distribution of organisms. Asteraceae is a well-represented family of flowering plants in this area; especially, the genus Stevia, with 25 species which inhabit different environments. The goals of this study were: 1) to model habitat suitability for five species of Stevia distributed in northwestern Argentina, and 2) to project such suitability under a possible greenhouse gas emission scenario by 2050. Species S. alpina, S. breviaristata, S. minor, S. vaga and S. yaconensis were analyzed. Results showed that, when comparing maps based on current and future climatic conditions, all Stevia species would undergo changes in their fitness ranges. The trends observed in both future climate scenarios are similar, although they show more drastic consequences in the rcp8.5 model. Stevia alpina, S. breviaristata and S. minor reduce their area of aptitude, while S. vaga and S. yaconensis experience an increase of said area. Except for S. minor, the species showed a major tendency to migrate from East to West, a phenomenon known as altitude shift. Stevia minor would be the more affected species in a higher gas emission scenario since it will suffer a reduction greater than 80% for its suitability values greater than 0.65.Facultad de Ciencias Naturales y Muse
A new method for nocturnal aerosol measurements with a lunar photometer prototype
This paper presents the preliminary results of nocturnal Aerosol Optical Depth (τa) and Angström Exponent (α) obtained from a new lunar photometer prototype, trade name Cimel CE-318U. Due to the variation of the moon's illumination inherent to the lunar cycle, the typical Langley-plot Method used in solar photometry to calibrate these instruments cannot be applied. In this paper, we propose three different methods to carry out the lunar-photometer calibration. In order to validate the results, we have selected three events which encompass seven nights and ten days under different atmospheric conditions, including several saharan dust intrusions episodes. Method#1 is introduced in this work as a modification of the usual Langley Method.The Aeronet sunphotometer at Izana has been calibrated within ˜ AERONET-EUROPE TNA supported by the European Community – Research Infrastructure Action under the FP7 “Capacities” specific programme for Integrating Activities, ACTRIS Grant Agreement no. 262254
WMO-CIMO testbed for aerosols and water vapor remote sensing instruments (Izaña, Spain)
Comunicación presentada en: TECO-2016 (Technical Conference on Meteorological and Environmental Instruments and Methods of Observation) celebrada en Madrid, del 27 al 30 de septiembre de 2016
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