10 resultados para MUSLE


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本文克隆了牙鲆的成肌因子MyoD和Myf5,以及牙鲆的Forkhead基因FoxD1、 FoxD3和FoxD5,并对其在牙鲆肌肉发育中的功能进行了分析。 牙鲆MyoD和Myf5基因都具有三个外显子,两个内含子。其编码的氨基酸序列都含有保守的bHLH;牙鲆FoxD1,FoxD3,FoxD5基因都只有一个外显子,编码的氨基酸序列都含有保守的翼状螺旋DNA结合结构域。 在胚胎发育早期,Myf5在近轴中胚层中表达,体节发生过程中,Myf5在体节中表达,MyoD基因最早在分节板的体节前细胞中表达,随后在近轴细胞、体节中表达;随着胚胎的发育,Myf5在成熟体节中表达量降低,在新生体节中表达较强;MyoD自30个体节时期后只在新生的尾部体节中表达,在成熟的体节中表达量降低;在孵化期,MyoD和 Myf5在头部及鳍的肌肉、尾部的体节中表达;生长期的牙鲆中,Myf5在骨骼肌和肠中表达,成体牙鲆中,Myf5只在肌肉中表达;生长期的牙鲆及成体牙鲆中,MyoD只在肌肉组织中表达。 牙鲆MyoD和Myf5的启动子可以驱动绿色荧光蛋白在斑马鱼肌肉纤维中表达,其包含了这两个基因正常表达所需的核心区域,并可以跨物种行使功能。 在胚胎发育早期,FoxD3在未迁移神经嵴前体细胞、体节、耳后的基板、头部和躯干的神经嵴细胞、松果体中表达。牙鲆FoxD1主要在脑,体节,肾脏及肠中表达。牙鲆FoxD5主要在体节、尾芽、前脑、耳泡中表达。 在斑马鱼中过量表达牙鲆FoxD3,并与斑马鱼的同源基因进行比较,结果表明注射牙鲆和斑马鱼FoxD3的斑马鱼胚胎表型一致,它们在中轴两侧的发育出现了不同步现象,MyoD和Myf5在近轴中胚层中的表达受到不同程度抑制。因此,FoxD3在不同物种之间保守,并且FoxD3在肌肉发育的调控通路中可能通过与MyoD和Myf5相互作用而行使功能。 在斑马鱼中过量表达FoxD1后,MyoD在一侧体节中的表达受到了严重抑制,而在近轴细胞中的表达未受影响,Myf5在体节前中胚层,近轴细胞,及体节中的表达都受到了抑制。FoxD1在胚胎发育的早期可能通过调控MyoD和Myf5的表达而参与肌肉发育的调控。 将牙鲆FoxD5在斑马鱼中过量表达,MyoD在一侧体节中的表达量有所升高,而在近轴细胞中的表达未受影响;Myf5在一侧体节和体节前中胚层中的表达也有所升高,表明牙鲆FoxD5可以调控肌肉调节因子MyoD和Myf5的表达而参与早期肌肉发育的调控。

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Medir la frecuencia de presentación de estrés de origen laboral en docentes de pre-escolar del municipio de Chía – Cundinamarca en el segundo periodo del año 2012.

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The sediment production in river basins is an important aspect for planning the land use. Mathematical models are useful tools for analyzing the problem by providing speed, convenience and flexibility to the simulations of current conditions and future. In this article we evaluate a methodology to simulate the sediment production combining the MUSLE, a hydrologic model (ABC) and a GIS in different scenarios of land use. The models used showed good performance for purposes of planning land use, as well as for agricultural and environmental planning.

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This study aimed to simulate and evaluate the sediment transport in Upper Basin Stream Cachoeirinha in Rio Claro, SP, and compare the results with previous studies performed in the same basin. The modeling software used in this study was Soil and Water Assessment Tool (SWAT), which is a very comprehensive tool that discusses many physical processes. In this work, the hydrosedimentological processes were treated, aiming to understand the sediment production and transport. The Basin Stream Cachoeirinha has an area with predominantly agricultural use, especially sugar cane. The database for inclusion in software was constructed from the following elements: climatic, topographical, soil type and use and land cover of the area, also including the parameters of Modified Universal Soil Loss Equation (MUSLE). The analysis was conducted for a period of 16 years (1994-2010), which is the range of data available from CEAPLA. The results were analyzed in terms of annual runoff and sediment yield. The average sediment delivery in the simulation was 0.94 t/ha/year, while the maximum annual contribution was 7.28 t/ha/year

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Introduction The purpose of this paper is to present the technical specifications of the Forensic Reference Phantom (FRP), to test its behavior relative to organic test materials, and discuss potential applications of the phantom in forensic radiology. Materials and method The FRP prototype is made of synthetic materials designed to simulate the computed tomography (CT) attenuation of water. It has six bore holes that accommodate multiuse containers. These containers were filled with test materials and scanned at 80 kVp, 120 kVp, and 140 kVp. X-ray attenuation was measured by two readers. Intra- and inter-reader reliability was assessed using the intra-class correlation coefficient (ICC). Significance levels between mean CT numbers at 80 kVp, 120 kVp, and 140 kVp were assessed with the Friedman-test. The T-test was used to assess significance levels between the FRP and water. Results Overall mean CT numbers ranged from −3.0–3.7HU for the FRP; −1000.3–−993.5HU for air; −157.7– −108.1HU for oil; 35.5–42.0HU for musle tissue; and 1301.5–2354.8HU for cortical bone. Inter-reader and intra-reader reliability were excellent (ICC>0.994; and ICC=0.999 respectively). CT numbers were significantly different at different energy levels. There was no significant difference between the attenuation of the FRP and water. Conclusions The FRP is a new tool for quality assurance and research in forensic radiology. The mean CT attenuation of the FRP is equivalent to water. The phantom can be scanned during routine post-mortem CT to assess the composition of unidentified objects. In addition, the FRP may be used to investigate new imaging algorithms and scan protocols in forensic radiology.

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En el ámbito de la llanura pampeana tienen lugar procesos degradativos que condicionan la actividad agrícola ganadera, vinculados con la erosión de tipo hídrica superficial. El presente trabajo busca modelar la emisión de sedimentos en una cuenca hidrográfica con forestaciones del Noreste Pampeano. La metodología implementada consiste en aplicar un modelo cartográfico cuantitativo desarrollado en base geoespacial con Sistema de Información Geográfica, apoyado en la Ecuación Universal de Pérdida de Suelo Modificada (MUSLE). Se realizó un análisis de validación estadística con ensayos de microsimulador de lluvias a campo, para una lluvia de 30 mm.h-1 de dos años de retorno. Los resultados obtenidos fueron mapas georreferenciados de cada factor de la MUSLE valorizados por color-intensidad, que alcanzan un valor de 33,77 Mg de sedimentos emitidos a la salida de la cuenca, con un coeficiente de correlación de 0,94 y un grado de ajuste de Nash-Sutcliffe de 0,82. Se concluye que el modelo cartográfico generó información espacial precisa de los componentes de la MUSLE para un evento de lluvia concreto. La aplicación del microsimulador de lluvias permitió la obtención de valores reales de emisión de sedimentos, lográndose un alto grado de ajuste. La emisión de sedimentos en la cuenca resultó ser leve a nula.

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La finalidad de este proyecto es el estudio de la recuperación del último tramo del arroyo de las Canteras a su paso por Castro del Río, eliminando el canal existente para dotar al arroyo de cierta naturalidad y proponiendo distintas alternativas que solucionen los problemas de erosión y los recurrentes problemas de inundaciones en la localidad. Para la realización del proyecto, se han analizado tanto las condiciones del tramo fluvial como las correspondientes a la cuenca vertiente mediante una caracterización completa. Por otro lado, se ha realizado un estudio hidrológico para calcular distintos caudales generados en la cuenca asociados a distintos periodos de retorno; varios estudios hidráulicos, fundamentalmente modelizaciones del comportamiento del canal con el software HEC-RAS; y un estudio de erosión hídrica utilizando el método MUSLE con el caudal asociado a un periodo de retorno de 500 años. Con los resultados obtenidos se ha establecido un diagnóstico de la problemática existente y se han planteado y modelizado distintas alternativas. Como medidas estructurales dentro del tramo destacan: el redimensionamiento del cauce eliminando el hormigón, la variación de la curva del canal y la disminución de la pendiente mediante la creación de una serie de saltos. Como soluciones estructurales fuera del tramo de estudio cabe señalar la creación de diques de laminación y una llanura de inundación artificial para disminuir el caudal. Finalmente como medida no estructural, se realizará un cambio de usos y prácticas de conservación del olivar a nivel de cuenca. En conclusión, con la restauración, aparte de la mejora ambiental que se pretende conseguir, se realizará una mejora social. Dicha mejora social se obtendrá evitando las frecuentes inundaciones y eliminando el impacto visual que produce el canal gracias a la mejora de la calidad del entorno. Además, se concienciará a los habitantes de la zona para que entiendan que la solución al mal estado y comportamiento de un curso de agua no proviene únicamente de una gran obra en la zona problemática, sino de la aportación individual para reducir e incluso eliminar la fuente del problema.

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Numerous studies in the last 60 years have investigated the relationship between land slope and soil erosion rates. However, relatively few of these have investigated slope gradient responses: ( a) for steep slopes, (b) for specific erosion processes, and ( c) as a function of soil properties. Simulated rainfall was applied in the laboratory on 16 soils and 16 overburdens at 100 mm/h to 3 replicates of unconsolidated flume plots 3 m long by 0.8 m wide and 0.15 m deep at slopes of 20, 5, 10, 15, and 30% slope in that order. Sediment delivery at each slope was measured to determine the relationship between slope steepness and erosion rate. Data from this study were evaluated alongside data and existing slope adjustment functions from more than 55 other studies from the literature. Data and the literature strongly support a logistic slope adjustment function of the form S = A + B/[1 + exp (C - D sin theta)] where S is the slope adjustment factor and A, B, C, and D are coefficients that depend on the dominant detachment and transport processes. Average coefficient values when interill-only processes are active are A - 1.50, B 6.51, C 0.94, and D 5.30 (r(2) = 0.99). When rill erosion is also potentially active, the average slope response is greater and coefficient values are A - 1.12, B 16.05, C 2.61, and D 8.32 (r(2) = 0.93). The interill-only function predicts increases in sediment delivery rates from 5 to 30% slope that are approximately double the predictions based on existing published interill functions. The rill + interill function is similar to a previously reported value. The above relationships represent a mean slope response for all soils, yet the response of individual soils varied substantially from a 2.5-fold to a 50-fold increase over the range of slopes studied. The magnitude of the slope response was found to be inversely related ( log - log linear) to the dispersed silt and clay content of the soil, and 3 slope adjustment equations are proposed that provide a better estimate of slope response when this soil property is known. Evaluation of the slope adjustment equations proposed in this paper using independent datasets showed that the new equations can improve soil erosion predictions.