oalib

Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99

Submit

Any time

2019 ( 21 )

2018 ( 41 )

2017 ( 38 )

2016 ( 65 )

Custom range...

Search Results: 1 - 10 of 36883 matches for " Velasco-Hernández "
All listed articles are free for downloading (OA Articles)
Page 1 /36883
Display every page Item
A model for the A(H1N1) epidemic in Mexico, including social isolation
Velasco-Hernández,Jorge X; Leite,Maria Conceicao A;
Salud Pública de México , 2011, DOI: 10.1590/S0036-36342011000100007
Abstract: objective: we present a model for the 2009 influenza epidemic in mexico to describe the observed pattern of the epidemic from march through the end of august (before the onset of the expected winter epidemic) in terms of the reproduction number and social isolation measures. material and methods: the model uses a system of ordinary differential equations. computer simulations are performed to optimize trajectories as a function of parameters. results: we report on the theoretical consequences of social isolation using published estimates of the basic reproduction number. the comparison with actual data provides a reasonable good fit. conclusions: the pattern of the epidemic outbreak in mexico is characterized by two peaks resulting from the application of very drastic social isolation measures and other prophylactic measures that lasted for about two weeks. our model is capable of reproducing the observed pattern.
Towards Uncertainty Quantification and Inference in the stochastic SIR Epidemic Model
Marcos A. Capistrán,J. Andrés Christen,Jorge X. Velasco-Hernández
Statistics , 2011,
Abstract: In this paper we introduce a novel method to conduct inference with models defined through a continuous-time Markov process, and we apply these results to a classical stochastic SIR model as a case study. Using the inverse-size expansion of van Kampen we obtain approximations for first and second moments for the state variables. These approximate moments are in turn matched to the moments of an inputed generic discrete distribution aimed at generating an approximate likelihood that is valid both for low count or high count data. We conduct a full Bayesian inference to estimate epidemic parameters using informative priors. Excellent estimations and predictions are obtained both in a synthetic data scenario and in two Dengue fever case studies.
Intraguild Predation on the Whitefly Parasitoid Eretmocerus eremicus by the Generalist Predator Geocoris punctipes: A Behavioral Approach
María Concepción Velasco-Hernández, Ricardo Ramirez-Romero, Lizette Cicero, Claudia Michel-Rios, Nicolas Desneux
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0080679
Abstract: Intraguild predation (IGP) takes place when natural enemies that use similar resources attack each other. The impact of IGP on biological control can be significant if the survival of natural enemy species is disrupted. In the present study, we assessed whether Geocoris punctipes (Hemiptera: Lygaeidae) engages in IGP on Eretmocerus eremicus (Hymenoptera: Aphelinidae) while developing on whitefly nymphs of Trialeurodes vaporariorum (Hemiptera: Aleyrodidae). In choice and non-choice tests, we exposed G. punctipes to parasitized and non-parasitized whitefly nymphs. We found that G. punctipes does practice IGP on E. eremicus. However, choice tests assessing G. punctipes consumption revealed a significant preference for non-parasitized T. vaporariorum nymphs. Subsequently, we investigated whether E. eremicus females modify their foraging behavior when exposed to conditions involving IGP risk. To assess this, we analyzed wasp foraging behavior under the following treatments: i) whitefly nymphs only (control = C), ii) whitefly nymphs previously exposed to a predator ( = PEP) and, iii) whitefly nymphs and presence of a predator ( = PP). In non-choice tests we found that E. eremicus did not significantly modify its number of attacks, attack duration, oviposition duration, or behavior sequences. However, E. eremicus oviposited significantly more eggs in the PEP treatment. In the PP treatment, G. punctipes also preyed upon adult E. eremicus wasps, significantly reducing their number of ovipositions and residence time. When the wasps were studied under choice tests, in which they were exposed simultaneously to all three treatments, the number of attacks and frequency of selection were similar under all treatments. These results indicate that under IGP risk, E. eremicus maintains several behavioral traits, but can also increase its number of ovipositions in the presence of IG-predator cues. We discuss these findings in the context of population dynamics and biological control.
Encuestas transversales
Hernández Bernardo,Velasco-Mondragón Héctor Eduardo
Salud Pública de México , 2000,
Abstract:
Semipersonalized Psychological Evaluation of Quality of Life of Hypertensive Patients in a trial with two Calcium Antagonists: a Multicenter Latinamerican Study (Lastlhy)
M Velasco,E Lezama,F Contreras,R Hernández
Archivos Venezolanos de Farmacología y Terapéutica , 2000,
Abstract: The main objective of this study was to evaluate well being and physical activity of two hundred and forty eight hypertensive patients, of which, one hundred and seventy seven were female, who had previously finished the Latin Amerícan Study on Lacidipine in Hypertension (LASTLHY). This was an open study carried out in twelve clinical centers situated in Argentina, Brazil, Colombia, Mexico and Venezuela, to compare, over a period of sixteen weeks, the antihypertensive actions of fixed-dose once daily oral monopharmacotherapy of 4 rng of lacidipine (n = 120) patients VS. 30 mg of nifedipine (n = 128) patients aged between 40-65 years old, with mild to moderate hypertension beginning at the end of a four weeks placebo run-in (end of week -1). Well being and physical activity were assessed through an experimental single questionnaire, which was administered taking into consíderation the physical and cultural diversities amongst the clinical centers and patients. The questionnaire included thirteen multiple-choice and eight contingent open questions. The score to each question was multiplied by a coefficient according to the importance of each question for each patient (semipersonal ization); the coefficient was evaluated from cultural and socioeconomic information collected at the time of enrollment. The semipersonalization was carried out by a blind psychological study with respect to the medication and had a high repeatability in the assignment of personalized coefficients to the score of each question. The scores of each question were added to obtain an overall weil being and activity scoring. The possible theoretical range for the overall scoring in this study was 10- 124.
Test of the heavy quark-light diquark approximation for baryons with a heavy quark
E. Hernández,J. Nieves,J. M. Verde-Velasco
Physics , 2008, DOI: 10.1016/j.physletb.2008.07.007
Abstract: We check a commonly used approximation in which a baryon with a heavy quark is described as a heavy quark-light diquark system. The heavy quark influences the diquark internal motion reducing the average distance between the two light quarks. Besides, we show how the average distance between the heavy quark and any of the light quarks, and that between the heavy quark and the center of mass of the light diquark, are smaller than the distance between the two light quarks, which seems to contradict the heavy quark-light diquark picture. This latter result is in agreement with expectations from QCD sum rules and lattice QCD calculations. Our results also show that the diquark approximations produces larger masses than the ones obtained in a full calculation.
Semipersonalized Psychological Evaluation of Quality of Life of Hypertensive Patients in a trial with two Calcium Antagonists: a Multicenter Latinamerican Study (Lastlhy)
Velasco,M; Lezama,E; Contreras,F; Hernández,R; Hernández,MJ; Alcocer,L; Reyes,A;
Archivos Venezolanos de Farmacología y Terapéutica , 2000,
Abstract: the main objective of this study was to evaluate well being and physical activity of two hundred and forty eight hypertensive patients, of which, one hundred and seventy seven were female, who had previously finished the latin amerícan study on lacidipine in hypertension (lastlhy). this was an open study carried out in twelve clinical centers situated in argentina, brazil, colombia, mexico and venezuela, to compare, over a period of sixteen weeks, the antihypertensive actions of fixed-dose once daily oral monopharmacotherapy of 4 rng of lacidipine (n = 120) patients vs. 30 mg of nifedipine (n = 128) patients aged between 40-65 years old, with mild to moderate hypertension beginning at the end of a four weeks placebo run-in (end of week -1). well being and physical activity were assessed through an experimental single questionnaire, which was administered taking into consíderation the physical and cultural diversities amongst the clinical centers and patients. the questionnaire included thirteen multiple-choice and eight contingent open questions. the score to each question was multiplied by a coefficient according to the importance of each question for each patient (semipersonal ization); the coefficient was evaluated from cultural and socioeconomic information collected at the time of enrollment. the semipersonalization was carried out by a blind psychological study with respect to the medication and had a high repeatability in the assignment of personalized coefficients to the score of each question. the scores of each question were added to obtain an overall weil being and activity scoring. the possible theoretical range for the overall scoring in this study was 10- 124.
Comportamiento de la placenta previa en el Hospital Ginecoobstétrico "América Arias", período 2003-2005 Behavior of placenta praevia in "América Arias" Gynecoobstetric Hospital from 2003 to 2005
Ariana Isla Valdés,Jeddú Cruz Hernández,Alejandro Velasco Boza,Pilar Hernández García
Revista Cubana de Medicina General Integral , 2008,
Abstract: Se realizó un estudio retrospectivo y descriptivo en el Hospital Ginecoobstétrico "América Arias" para identificar la relación que existe entre la aparición de la placenta previa y la presencia de algunas variables obstétricas, además de su repercusión en la morbimortalidad materna y perinatal en el período comprendido desde enero de 2003 hasta diciembre de 2005. Se revisaron 62 historias clínicas, que se corresponden con igual número de mujeres que presentaron placenta previa en esta fecha, y se encontró que el aumento de la frecuencia de la placenta previa se relacionó fundamentalmente con la edad mayor que 30 a os (75,5 % de los casos), la paridad elevada (58 % de las mujeres eran multíparas), y la cesárea y los legrados previos (32,3 y 25,8 % de las gestantes, respectivamente). Al 67,8 % de los casos se les hizo el diagnóstico en la atención primaria. Las complicaciones maternas más frecuentes fueron la anemia posparto (29 % de los casos) y el alumbramiento distócico (17,7 % de las mujeres), mientras que en el recién nacido, el bajo peso y el distrés respiratorio (29 y 25,8 % de los neonatos, respectivamente). A retrospective and descriptive study was undertaken at "América Arias" Gynecoobstetric Hospital to identify the relationship existing between the appearance of placenta praevia and the presence of some obstetric variables, in addition to its impact on maternal and perinatal morbimortality from January 2003 to December 2005. 62 medical histories corresponding to the same number of females that presented placenta praevia on this date were reviewed. It was found that the increase of the frequency of placenta praevia was mainly related to age over 30 (75.5 % of the cases), an elevated parity (58 % of the females were multiparous), and the cesareans and the previous induced abortions (32.3 and 25.8 % of the pregnant women, respectively) 67.8 % of the cases were diagnosed at the primary health care level. The most common maternal complications were postpartum anemia (29 % of the cases) and distocic delivery (17.7 % of the females), whereas in the newborn infant, low birth weight and respiratory distress (29 y 25.8 % of the neonates, respectively) proved to be the most frequent complications.
La actitud hacia los límites sociales de jóvenes de 12 a 20 a os de tres religiones
Nadya Luz Velasco Castellón,Luis Antonio Hernández Hernández,Hans Oudhof van Barneveld
Ciencia Ergo Sum , 2009,
Abstract: Se investigó la actitud hacia los límites sociales de jóvenes católicos, de la Iglesia de Jesucristo de los Santos de los últimos Días y Testigos de Jehová. La muestra fue de 120 jóvenes con edades entre los 12 y 20 a os, 50% hombres y 50% mujeres; 40 de cada grupo religioso, a los que se aplicó la versión mexicana de la escala para medir la actitud hacia los límites sociales (Rink, Boersma, Lutje Spelberg y Vos, 2000). Se observó una tendencia generalizada en los tres grupos a ajustarse a los límites sociales, al ser ésta la reacción más conocida y preferida. En la comparación de las actitudes por grupo religioso aparecieron diferencias estadísticamente significativas: los jóvenes católicos muestran una mayor inclinación conductual a transgredir los límites sociales en relación con los otros dos grupos, que optan más por ajustarse y negociar. Los límites más transgredidos fueron respetar las normas de convivencia, no usar violencia física contra personas y el cuidado del medio ambiente y la naturaleza.
Role of Angiotensin II Receptor Antagonists in Hipertensión
Rafael Hernández Hernández,Manuel Velasco,María de la Parte,María José Hernández
Archivos Venezolanos de Farmacología y Terapéutica , 2000,
Abstract:
Page 1 /36883
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.