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Ecología poblacional de Crocodylus acutus en los sistemas estuarinos de San Blas, Nayarit, México
Hernández-Hurtado, Helios;Romero-Villaruel, José de Jesús;Hernández-Hurtado, Pablo Simitrius;
Revista mexicana de biodiversidad , 2011,
Abstract: this study was conducted in san blas estuaries during june 2005 and february 2006 (dry season) and october 2005 and october 2007 (rainy season). the purpose was to describe the population of crocodiles according to its distribution and abundance. spotlight surveys counting animals found per kilometer were done navigating 89 kilometers in 6 transects. transects a, b and c had a density from 2.68 to 4.31 crocodiles/kilometer or 0.05 crocodiles/ha, with 26 active nests, 6 different types of vegetation and salinity from 11.03‰ in dry season to 4.92‰ in rainy season. transects d, e and f had a density from 0.014 to 0.36 crocodiles/km or 0.002 crocodiles/ha, any nest was found, 1 single type of vegetation and salinity from 35.85‰ in dry season to 24.56‰ in rainy season. statistical similarity in transects a, b and c was 80%, in transects d and e was 70% and in transect f was 10%. crocodile population was estimated in 333 crocodiles and all sizes were represented. the habitat in san blas estuaries allows crocodylus acutus develop properly its biological cycle.
Ecología poblacional de Crocodylus acutus en los sistemas estuarinos de San Blas, Nayarit, México Population ecology of Crocodylus acutus in the estuarine systems of San Blas, Nayarit, Mexico
Helios Hernández-Hurtado,José de Jesús Romero-Villaruel,Pablo Simitrius Hernández-Hurtado
Revista mexicana de biodiversidad , 2011,
Abstract: El presente estudio se realizó en los meses de junio 2005 y febrero 2006 (estiaje), y en octubre 2005 y octubre 2007 (lluvias), en los esteros de San Blas. El objetivo fue caracterizar la población de cocodrilos a partir de su distribución y abundancia, El método utilizado consistió en recorridos nocturnos en los esteros, para contabilizar el número de individuos por kilómetro. Se realizaron 6 transectos recorriendo un total de 89 kilómetros. Los transectos A, B y C presentaron una densidad que osciló entre 2.68 y 4.31 ind/km o 0.05 ind/ha con 26 nidos activos, 6 tipos de vegetación y salinidad de 11.03‰ en estiaje a 4.92‰ en lluvias. Los transectos D, E y F presentaron una densidad que osciló entre 0.014 y 0.36 ind/km o 0.002 ind/ha, sin nidos, 1 tipo de vegetación y salinidad qosciló de 35.85‰ en estiaje a 24.56‰ en lluvias. Se obtuvo la similitud estadística en A, B y C= 80%, D y E= 70% y en F= 10% respecto a los demás. La población estimada fue de 333 cocodrilos, registrando todas las clases-talla, donde el hábitat disponible presenta las características necesarias para que Crocodylus acutus realice su ciclo biológico. This study was conducted in San Blas estuaries during June 2005 and February 2006 (dry season) and October 2005 and October 2007 (rainy season). The purpose was to describe the population of crocodiles according to its distribution and abundance. Spotlight surveys counting animals found per kilometer were done navigating 89 kilometers in 6 transects. Transects A, B and C had a density from 2.68 to 4.31 crocodiles/kilometer or 0.05 crocodiles/ha, with 26 active nests, 6 different types of vegetation and salinity from 11.03‰ in dry season to 4.92‰ in rainy season. Transects D, E and F had a density from 0.014 to 0.36 crocodiles/km or 0.002 crocodiles/ha, any nest was found, 1 single type of vegetation and salinity from 35.85‰ in dry season to 24.56‰ in rainy season. Statistical similarity in transects A, B and C was 80%, in transects D and E was 70% and in transect F was 10%. Crocodile population was estimated in 333 crocodiles and all sizes were represented. The habitat in San Blas estuaries allows Crocodylus acutus develop properly its biological cycle.
Observaciones, durante un ciclo de 24 horas, de las preferencias termales del Cocodrilo de Río (Crocodylus acutus) en cautiverio
Fabio Germán Cupul-Maga?a,Abraham Reyes-Juárez,Helios Hernández-Hurtado,Pablo S Hernández-Hurtado
Latin American Journal of Conservation , 2010,
Abstract: Tanto en condiciones silvestres como en cautiverio, los cocodrilos utilizan los termogradientes de su entorno para regular sutemperatura corporal interna. En este estudio realizado durante un ciclo de 24 horas dentro de un acuaterrario en México, se observaron las preferencias termales de cuatro ejemplares de Cocodrilo de Río (Crocodylus acutus), utilizando termómetros digitales ajustados a sus cuerpos. La temperatura ambiental, del agua y la intensidad luminosa del acuaterrario, también se registró durante este mismo periodo con termómetros digitales. La comparación de los patrones de temperatura ambiental y del agua con la de los cocodrilos, mostró que aquellos ejemplares que incursionaron en el agua del estanque, experimentaron menores gradientes térmicos (reflejado como bajos valores de coeficiente de variación) que aquellos que no lo hicieron y que sólo recurrieron a los espacios sombreados. Estos patrones diferentes de temperatura entre los cocodrilos, evidenciaron la necesidad de habilitar el acuaterrario con elementos que permitan realizar termorregulaciones adecuadas (como cobertura vegetal, ventilación y ampliación de pileta de agua) ya que se observó que los ejemplares se encontraban muy poco desarrollados en tallan both wild and captive conditions, crocodiles use thermal gradients in the environment to regulate their internal body temperature. This study was undertaken over a 24 hour period in a captive environment in Mexico. The thermal preferences of four American Crocodiles (Crocodylus acutus) were observed using external digital thermometers that were attached to the body of the crocodiles. We also recorded the air and water temperatures and light intensity using digital thermometers within the enclosure. The comparison of data on the temperatures of the air, water, crocodiles showed that individuals who entered the water experienced smaller thermal gradients (reflected by low values in the variation coefficient) than those that moved to shaded areas of the enclosure. These differences in temperature between crocodiles are evidence for the need to provide different elements that allow for adequate thermoregulation (such as vegetative cover, ventilation, and pools of water). The absence of these features could be the cause of the slow growth of some of these individuals.Key words: Animal wellness, Behavior, Crocodylidae, Farming, Temperature, Thermoregulation.
Efecto de tres dietas en el crecimiento de crías de cocodrilo americano Crocodylus acutus
Hernández-Hurtado,P.S.; Nolasco-Soria,H.; Hernández-Hurtado,H.; Cupul-Maga?a,F.G.; Jaime-Ceballos,B.; Galindo-López,J.; Carrillo-Farnés,O.; Vega-Villasante,F.;
Archivos de Zootecnia , 2012, DOI: 10.4321/S0004-05922012000200018
Abstract: the effect of three diets with replacement of marine fish (20 and 40%) for beef liver in the growth and survival, and the effect of temperature on feed intake of young crocodylus acutus was studied. crocodiles fed the 40% of liver had the highest growth and 100% survival, with potential for greater tolerance to winter conditions.
Lattice scars: Surviving in an open discrete billiard
Víctor Fernández-Hurtado,Jordi Mur-Petit,Juan José García-Ripoll,Rafael A. Molina
Physics , 2013, DOI: 10.1088/1367-2630/16/3/035005
Abstract: We study quantum systems on a discrete bounded lattice (lattice billiards). The statistical properties of their spectra show universal features related to the regular or chaotic character of their classical continuum counterparts. However, the decay dynamics of the open systems appear very different from the continuum case, their properties being dominated by the states in the band center. We identify a class of states ("lattice scars") that survive for infinite times in dissipative systems and that are degenerate at the center of the band. We provide analytical arguments for their existence in any bipartite lattice, and give a formula to determine their number. These states should be relevant to quantum transport in discrete systems, and we discuss how to observe them using photonic waveguides, cold atoms in optical lattices, and quantum circuits.
La biblioteca virtual especializada de los derivados de la ca a de azúcar: consideraciones, experiencias y perspectivas
Hernández Curbelo, Maby,Hurtado Vargas, Rafael
Revista Espa?ola de Documentación Científica , 2011,
Abstract: In this paper, the results of a project for the design and implementation of a specialized virtual library for sugar cane by-products are presented, including initial considerations, an architecture for working in a web environment, and the basic characteristics of software for managing a digital collection. This library supports research into sugar cane by-products and also represents an initial step toward the creation of a specialized virtual centre of information and knowledge for the sugar industry. En este trabajo se describen los resultados del proyecto de dise o e implementación de la biblioteca virtual especializada sobre los derivados de la ca a de azúcar. Se abordan consideraciones, arquitectura de trabajo en ambiente de Internet y características básicas del software para la administración de su colección digital. Esta biblioteca es soporte para la investigación sobre los derivados de la ca a de azúcar y constituye el paso inicial hacia la creación de un centro virtual especializado de información y conocimiento para el sector azucarero.
Perfil local y agroindustria palmera: explorando el caso de San Alberto y San Martín (Cesar)
Hurtado,Mónica; Hernández-Salazar,Giovanni Andrés;
Cuadernos de Desarrollo Rural , 2010,
Abstract: this article establishes the municipal profile of two places in colombia which are traditionally known for their palm tree production: san alberto and san martin (cesar). socioeconomic indicators, public finance, and armed conflict dynamics during the last ten years in both places are studied in particular. it was found out that san alberto, with greater palm tree activity than san martin, has lower poverty levels and better public finance. nevertheless, both municipalities show fragile standards in relation to education and health. as for safety and armed conflict, it was determined that the number of kidnappings and murders decreased in both places, but civilians are still victims of forced displacement.
Variación del estado del mar al paso de las ondas tropicales por el mar Caribe.
Marina Sosa Hurtado,Acacia del Sol Hernández
Revista de Climatología , 2002,
Abstract: El mar Caribe está frecuentemente afectado por ondas tropicales desde mayo hasta noviembre. Estos sistemas siempre incrementan el viento y el oleaje. En el presente trabajo fueron estudiadas cinco temporadas (1985-89) de ondas en esa zona geográfica. Se observó que estos sistemas incrementan a su paso el oleaje en 1,5 m. Cuando el patrón nuboso estaba mejor organizado este incremento fue superior.
Trastornos del sue o en el paciente con dolor crónico Sleep disturbances in patients with chronic pain
A. B. Mencías Hurtado,J. L. Rodríguez Hernández
Revista de la Sociedad Espa?ola del Dolor , 2012,
Abstract: Padecer dolor crónico supone un importante impacto sobre la calidad del sue o del paciente que lo sufre. Una mayor intensidad de dolor se ha asociado a una mayor prevalencia de trastornos del sue o, siendo esta relación recíproca y que perpetúa un círculo vicioso entre ambos. Teniendo en cuenta que algunos de los fármacos que manejamos habitualmente para el control analgésico, fundamentalmente opioides, pueden modificar la arquitectura del sue o, tanto positiva como negativamente, consideramos importante empezar a valorar la calidad del sue o del paciente con dolor crónico como un indicador de calidad en el manejo del tratamiento analgésico. Having chronic pain is a significant impact on sleep quality of the patient who suffers. Higher pain intensity was associated with a higher prevalence of sleep disorders, this being a mutual and perpetuating a vicious circle between them. Given that some of the drugs commonly used to manage pain control, mainly opioids, may alter the sleep architecture, both positively and negatively, we consider important to begin to assess this quality of sleep of patients with chronic pain as an indicator of quality management of analgesic treatment.
Mechanosynthesis as a Simple Method to Obtain a Magnetic Composite (Activated Carbon/Fe3O4) for Hyperthermia Treatment  [PDF]
Jorge Carlos Ríos-Hurtado, Elia Martha Múzquiz-Ramos, Alejandro Zugasti-Cruz, Dora Alicia Cortés-Hernández
Journal of Biomaterials and Nanobiotechnology (JBNB) , 2016, DOI: 10.4236/jbnb.2016.71003
Abstract:

A large number of magnetic nanomaterials have been studied for their hyperthermic potential, such as iron oxide based materials. These are embedded in different matrices to improve their properties. In this paper magnetite was synthesized by the coprecipitation method and an activated carbon/magnetite composite was obtained by mechanosynthesis (400 rpm, 3 h). The samples were characterized by X-ray diffraction (XRD), vibrating sample magnetometer (VSM), IR-FT spectroscopy and Scanning Electron Microscopy (SEM). Furthermore, composite heating curves as well as hemolysis tests were performed. The composite showed a superparamagnetic behavior due to its low coercivity index (8.92 Oe) and a high saturation magnetization (40.12 emu/g). SEM images showed that the magnetite was observed on the surface of activated carbon and also the IR-FT spectra indicated that oxygenated groups on the activated carbon surface were responsible for the anchoring of magnetite in the surface, with particle sizes between 9 and 14 nm. Heating results indicated that a composite mass of 18 mg reach a temperature of 45.6°C in a low frequency magnetic field (10.2 kA and 200 kHz). Hemolysis tests indicated that the composite is a non-hemolytic material (4.7% hemolysis). These results demonstrate that the material can be used in magnetic hyperthermia techniques for cancer treatment.

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