9,607 research outputs found
Anquilosis de la articulación coxofemoral y alteraciones biomecánicas en un individuo medieval de la necrópolis de la catedral de Sigüenza (Guadalajara)
X Congreso Nacional de Paleopatología. Univesidad Autónoma de Madrid, septiembre de 200
Analysis of the start to the first hurdle in 110m hurdles at the IAAF World Athletics Championships Beijing 2015
The purpose of this study was to use observational analysis to evaluate the relationships between variables
measured at the start of the men’s 110 hurdles event and race performance itself. Data were obtained for
competitors in 2015 IAAF World Athletics Ch
ampionships, in Beijing, China. The athletes’ start was quantified
by reaction time and time to the first hurdle; their action over the first hurdle was quantified by the take
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off
distance (i.e., the distance from the last step to the first hurdle), the la
nding distance, and the total distance
in the air over the first hurdle. Regression analyses revealed that the combination of one measure of the start
(either reaction time or time to the first hurdle) and the measure of propulsion over the first hurdle (d
istance
in air over the first hurdle) predicted performance (SEE = 0.23 s in the heats, SEE = 0.16 s in the semi
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finals,
SEE = 0.09 s in the finals). In addition, looking at performances in the finals, where all athletes with available
data used a seven
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st
ep approach to the first hurdle, inclusion of stride length data improved the prediction
somewhat (SEE = 0.07 s). The results demonstrate that a combination of a fast start, rapid acceleration, and
strong drive over the first hurdle quantifiably explains a
nd contributes to performance in the men’s 110 m hurdles at the highest level
Editorial: New insights into understanding and managing NAFLD
Non-alcoholic fatty liver disease (NAFLD) is a multisystem disease with complications related to the metabolic syndrome and with a diverse histopathological spectrum ranging from simple steatosis, also termed fatty liver (NAFL) without significant inflammation to steatohepatitis (NASH) with varying stages of fibrosis and, ultimately, cirrhosis, and hepatocellular carcinoma. Since NAFLD is the most common chronic liver disease worldwide, causing a considerable health burden, there is an increasing number of research groups that are deeply interested in the identification of risk factors involved in the progression of the liver damage, the characterization of new biomarkers with utility for its non-invasive diagnosis and the recognition of novel molecular targets for its treatment.Fil: Escribano, Óscar. Universidad Complutense de Madrid; EspañaFil: Frances, Daniel Eleazar Antonio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Fisiología Experimental. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Fisiología Experimental; ArgentinaFil: Otero, Yolanda F.. Valbiotis; FranciaFil: Egea, Javier. Universidad Autonoma de Madrid. Hospital Universitario de la Princesa; EspañaFil: González Rodríguez, Águeda. Centro de Investigación Biomédica En Red de Diabetes y Enfermedades Metabólicas Asociadas; Argentina. Instituto de Salud Carlos III; Españ
Tin oxide preparation and characterization and use as a catalyst in the reaction of unsaturated fatty esters epoxidation
La síntesis y la caracterización del óxido de estaño se estudiaron en este trabajo para evaluar su actividad catalítica en
la reacción de epoxidación del metilricinoleato proveniente del aceite de ricino. La obtención del óxido se realiza por
el método de precipitación controlada, encontrándose que se obtienen ventajas significativas al emplear soluciones
acuosas de SnCl2.2H2O como precursor. Su caracterización se efectuó por medio de las técnicas de DTA, TGA, DRX,
encontrándose que para obtener un alto rendimiento hacia el sistema casiterita el valor de pH óptimo fue de 6.25,
mientras que un pH de 8.0 conlleva hacia el sistema romarchita. En el caso de las técnicas de MEB y área superficial,
se determinó que el tamaño de partícula encontrado estaba por debajo de los 50 nm con un área superficial de 19 m2/g.
El ester ricinoleico se obtuvo a partir del aceite empleando metilato de sodio como catalizador y seguidamente se hace
reaccionar con peróxido de hidrógeno como agente oxidante y óxido de estaño para producir un epóxido. Finalmente,
los productos de reacción se identifican por cromatografía de gases, encontrando que los óxidos de estaño son activos
para la obtención de epóxidos con un mejor desempeño del sistema cristalino romarchita (SnO) principalmente hacia
el metil-12-hidroxi-9,10-epoxioctadecanoato (MHEOD). Abstract
Tin oxide synthesis and characterization were studied in the present work in order to evaluate its catalytic activity
in the reaction of methyl ricinoleate from castor oil. Oxide is obtained through the controlled precipitation method,
and significant advantages are obtained when using water solutions of SnCl2.2H2O as precursor. Its characterization
was done using the techniques DTA, TGA, XRD, finding that in order to have high performance for the cassiterite
system the optimum pH value was 6,25 whereas a pH of 8.0 was leading to the romarchite system. When using SEM
techniques and a surface area, the size of the particle found was below 50 nm with a surface area of 19 m2/g. The
ricinoleate ester was obtained from the oil using sodium methylate as catalyst and then making it react with hydrogen
peroxide as oxidant agent and tin oxide to produce an epoxide. Finally, reaction products are identified through gas
chromatography finding that tin oxides are active for obtaining epoxides with better performance of the romarchite
crystal system (SnO) especially towards the methyl-12-hydroxi-9, 10-epoxioctadecanote (MHEOD)
Membrana pupilar persistente
La persistencia de la membrana pupilar es una de las alteraciones congénitas oculares más frecuente en los pequeños animales. En este artículo se hace una revisión de las manifestaciones clínicas más frecuentes de esta patología.The persistence of the pupillary membrane is one of the most common congenital ocular anomalies in small animals. In this article a review of the principal clinical signs of this alteration is made
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