557 research outputs found
Evaluación de la seguridad hidrológica de las presas bajo un enfoque probabilístico
El presente trabajo realiza una propuesta metodológica para evaluar la seguridad hidrológica de una presa, con aplicación práctica para el diseño probabilístico de aliviaderos. La metodología consiste en la generación y análisis de numerosas avenidas junto con el desarrollo de un modelo que permite obtener una descripción probabilística del comportamiento del aliviadero frente a las variables estudiadas. El trabajo es una combinación de técnicas previamente desarrolladas para plantear un nuevo enfoque metodológico en un problema de gran trascendencia práctica: la seguridad hidrológica de las presas. El principal aporte del documento se constituye en el estudio de un conjunto representativo de los posibles hidrogramas de entrada al embalse en lugar de un único hidrograma de proyecto. Esto permite el análisis probabilístico de los resultados, lo que facilita la incorporación de la incertidumbre hidrológica en las decisiones de diseño. De esta forma se ha desarrollado un entorno de cálculo que permite el estudio de numerosos hietogramas y su respuesta en la cuenca con un bajo costo de tiempo de cómputo por lo que viabiliza la utilización de este tipo de herramientas y planteamientos probabilísticos con un esquema de simulación de Monte Carlo; siendo una herramienta muy útil para realizar estudios de evaluación de seguridad hidrológica de presas así como de sensibilidad de cada una de las variables que intervienen. Asimismo, un abordaje probabilístico al tema permite el estudio del universo de posibles soluciones con su incertidumbre asociada como contraposición a los métodos determinísticos usualmente utilizados. Entre otros factores, la metodología de análisis planteada permite analizar la influencia de la forma del hietograma e hidrograma de entrada en el efecto laminador del embalse y puede observarse la existencia de una importante influencia de la forma de los hietogramas en la respuesta de la cuenca y los valores máximos de caudal en la entrada del embalse
PLK1 regulates centrosome migration and spindle dynamics in male mouse meiosis
Cell division requires the regulation of karyokinesis and cytokinesis, which includes an essential role of the achromatic spindle. Although the functions of centrosomes are well characterised in somatic cells, their role during vertebrate spermatogenesis remains elusive. We have studied the dynamics of the meiotic centrosomes in male mouse during both meiotic divisions. Results show that meiotic centrosomes duplicate twice: first duplication occurs in the leptotene/zygotene transition, while the second occurs in interkinesis. The maturation of duplicated centrosomes during the early stages of prophase I and II are followed by their separation and migration to opposite poles to form bipolar spindles I and II. The study of the genetic mouse model Plk1(Δ/Δ) indicates a central role of Polo-like kinase 1 in pericentriolar matrix assembly, in centrosome maturation and migration, and in the formation of the bipolar spindles during spermatogenesis. In addition, in vitro inhibition of Polo-like kinase 1 and Aurora A in organotypic cultures of seminiferous tubules points out to a prominent role of both kinases in the regulation of the formation of meiotic bipolar spindlesThis work was supported by funding from Ministerio de Economía, Industria y Competitividad, Gobierno de España (MINECO) (Spain) [grant number BFU2014-53681-P and MEIONET (BFU2015-71786-REDT) to J. A. S. and grant number RTI2018-095582-B-I00 to M. M.]
Towards a more complete description of nucleon distortion in lepton-induced single-pion production at low-
Theoretical predictions for lepton-induced single-pion production (SPP) on
C are revisited in order to assess the effect of different treatments of
the current operator. On one hand we have the asymptotic approximation, which
consists in replacing the particle four-vectors that enter in the operator by
their asymptotic values, i.e., their values out of the nucleus. On the other
hand we have the full calculation, which is a more accurate approach to the
problem. We also compare with results in which the final nucleon is described
by a relativistic plane wave, to rate the effect of the nucleon distortion. The
study is performed for several lepton kinematics, reproducing inclusive and
semi-inclusive cross sections belonging to the low- region (between 0.05
and 1 GeV), which is of special interest in charged-current (CC)
neutrino-nucleus 1 production. Inclusive electron results are compared
with experimental data. We find non-trivial corrections comparable in size with
the effect of the nucleon distortion, namely, corrections up to 6\%, either
increasing or diminishing the asymptotic prediction, and a shift of the
distributions towards higher energy transfer. For the semi-inclusive cross
sections, we observe the correction to be prominent mainly at low values of the
outgoing nucleon kinetic energy. Finally, for CC neutrino-induced 1
production, we find a reduction at low- with respect to both the
plane-wave approach and the asymptotic case
Docker security in web simulation tools: a layered approach
International Conference on Wireless Networks and Mobile Communication (EUIWNMC), 26/08/2021-27/08/2021, Marrakesh, Marruecos.In this work, container security issues and strengths are studied using Docker as the main implementation. First,
the container infrastructure is described and compared against the traditional approach of virtual machines. Secondly, the
Docker containers security is discussed by the different infrastructure layers that compose them and different solutions are
proposed to try to decrease the attack surface over this kind of applications.Universidad de Alcal
Gingival neurofibroma in a neurofibromatosis type 1 patient : case report
Neurofibroma is a benign peripheral nerve sheath tumour. It is one of the most frequent tumours of neural origin and its presence is one of the clinical criteria for the diagnosis of type 1 neurofibromatosis (NF-I). Neurofibromatosis type 1 is an autosomal dominantly inherited disease due to an alteration in the long arm of chromosome 17. About 50% of NF-I patients have no family history of the disease. NF-I patients have skin lesions (café au lait spots and neurofibromas) as well as bone malformations and central nervous system tumours. Diagnosis is based on a series of clinical criteria. Gingival neurofibroma in NF-I is uncommon. Treatment of neurofibromas is surgical resection. The aim of this paper is to report a case of NF-I with gingival involvement and to review the literature
Neck circumference and clustered cardiovascular risk factors in children and adolescents: Cross-sectional study
Objective Early detection of cardiovascular disease (CVD) risk factors, such as obesity, is crucial to prevent adverse long-term effects on individuals'' health. Therefore, the aims were: (1) to explore the robustness of neck circumference (NC) as a predictor of CVD and examine its association with numerous anthropometric and body composition indices and (2) to release sex and age-specific NC cut-off values to classify youths as overweight/obese. Design Cross-sectional study. Setting 23 primary schools and 17 secondary schools from Spain. Participants 2198 students (1060 girls), grades 1-4 and 7-10. Measures Pubertal development, anthropometric and body composition indices, systolic and diastolic blood pressure (SBP and DBP, respectively), cardiorespiratory fitness, blood sampling triglycerides (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-c), low-density lipoprotein cholesterol (LDL-c), glucose and inflammatory markers. Homoeostasis model assessment (HOMA-IR) and cluster of CVD risk factors were calculated. Results NC was positively correlated with all anthropometric and body composition indices. NC was negatively associated with maximum oxygen consumption (R 2 =0.231, p<0.001 for boys; R 2 =0.018, p<0.001 for girls) and positively associated with SBP, DBP, TC/HDL-c, TG, HOMA, complement factors C-3 and C-4, leptin, adiponectin and clustered CVD risk factor in both sexes (R 2 from 0.035 to 0.353, p<0.01 for boys; R 2 from 0.024 to 0.215, p<0.001 for girls). Moreover, NC was positively associated with serum C reactive protein, LDL-c and visfatin only in boys (R 2 from 0.013 to 0.107, p<0.05). Conclusion NC is a simple, low-cost and practical screening tool of excess of upper body obesity and CVD risk factors in children and adolescents. Paediatricians can easily use it as a screening tool for overweight/obesity in children and adolescents. For this purpose, sex and age-specific thresholds to classify children and adolescents as normal weight or overweight/obese are provided
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