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Search Results: 1 - 10 of 333218 matches for " Manuel J. González "
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“I took Panama”
Manuel J. González
Revista Derecho del Estado , 2002,
Abstract:
Substituent, Temperature and Solvent Effects on the Keto-Enol EQUILIBRIUM in β-Ketoamides: A Nuclear Magnetic Resonance Study  [PDF]
Sergio L. Laurella, Manuel González Sierra, Jorge J. P. Furlong, Patricia E. Allegretti
Open Journal of Physical Chemistry (OJPC) , 2013, DOI: 10.4236/ojpc.2013.34017
Abstract:

Substituent, temperature and solvent effects on tautomeric equilibria in several β-ketoamides have been investigated by means of nuclear magnetic resonance spectroscopy (NMR). Keto-enol equilibrium predominates over the amide-imidol one. The relative stability of the individual tautomers and the corresponding equilibrium shifts are explained considering electronic and steric effects and tautomer stabilization via internal hydrogen bonds. In solution, these compounds exist mainly as ketoamide and Z-enolamide tautomers, both presenting intramolecular hydrogen bonds.

Influencia de la longitud del recipiente y la ubicación de las sillas en los esfuerzos circunferenciales de recipientes horizontales usando el método de elementos de contorno
GONZáLEZ D,MARCO; MARTíNEZ,MANUEL J;
Revista de la Facultad de Ingeniería Universidad Central de Venezuela , 2006,
Abstract: in this article, a stress analysis based on the 3-d boundary element method to determine the influence of the parameters:vessel length and saddles location, on the values of circumferential stress at horn of the saddles in horizontal pressure vessels on two saddles, is presented. the ntegral equation obtained for this problem includes the volume integral of the body forces, represented by self-weight of vessel. the domain integral is transformed into boundary integral using the method recommended by beer. in this work, three different saddle locations (a/r1 ratio) and five different tangent-totangent lengths of vessel are used. the numerical results obtained are compared to zick analysis, most popular method to design horizontal vessels, obtaining agreed results.
Medición del contenido calórico de la mata de cobre (Cu2S-FeS) usando un calorímetro de gota
J. Manuel González,Francisco Pati?o,Eleazar Salinas
Revista de la Sociedad Química de México , 2001,
Abstract: El propósito de este trabajo fue determinar el contenido calórico de la mata de cobre (Cu2S-FeS) para evaluar el balance de calor en el convertidor de cobre. Los contenidos de calor de algunas matas (Cu2-FeS) fueron determinados en un intervalo de temperaturas de 1073 a 1473 K usando un calorímetro de gota. Los contenidos de calor de 100 % FeS, 75 % FeS-25 % Cu2S, 50 % FeS-50 % Cu2S, 25 % FeS-75 % Cu2S y 100 % Cu2S a 1473 K son 1253, 1134, 1008, 879 y 756 J/g, respectivamente, disminuyendo cuando se incrementa el grado de la mata.
Efecto de las políticas económicas en los recursos naturales y el medio ambiente en México
González-Acolt, Roberto;Matus-Gardea, J. Arturo;González-Guillén, Manuel;
Agrociencia , 2008,
Abstract: the purpose of the present study was to contribute to the evaluation of the effect of economic policy in méxico, in relation to the natural resources and the environment. an extended social accounting matrix was built with environmental data for méxico with base year 2001 (mcsa-mex2001). the calculation of environmental multipliers of costs from depletion and degradation was the principal instrument for analyzing the effect of an increase in the variables of economic policy (exogenous expenditure) on the use of the natural resources and its influence on the environment. it was found that the sectors with highest incidence in the national income contributed the most to the depletion of the natural resources and environmental deterioration when they receive an injection of exogenous expenditure. furthermore, a monetary increment of an exogenous variable in all of the productive activities has a greater effect on air pollution.
Programa de prevención y control de la transmisión vertical del VIH en Cuba: Enero de 1986 - diciembre de 2007
González N,Ida; Díaz J,Manuel; Verdasquera C,Denis; Pérez á,Jorge;
Revista chilena de infectología , 2010, DOI: 10.4067/S0716-10182010000500006
Abstract: the hiv/aids epidemic continues to increase in spite of the strategies developed, including the use of haart. one of the vulnerable populations is the child of hiv+ mothers. in cuba, a prevention and control program of hiv infection was implemented in 1986 and one of the key aims was to reduce perinatal infection. in this study, the medical records of all 314 children born to hiv/aids positive mothers between january 1986 to december 2007 are described. our aim was to determine the relationship between program compliance and prevention of vertical transmission (vt). a total of 248/314 infants completed a full virological evaluation at the time of this report 32 (12.9%) were hiv-infected. in these 32 children, mortality due to aids related events was 31.2%, of which 60% died before their first year of life. vt rate decreased from 50,0% to 14,6% after implementation of prophylactic caesarean section and to 2.2% in 99 women complying with the new adopted program including haart antiviral therapy in pregnant woman, caesarean section, and azt to the newborn. the effectiveness of combining a caesarean section and haart was 95.2%. the prevention program for hiv/aids vertical transmission implemented in cuba has been effective in reducing vt, similar to other worldwide reports.
A new hypothesis about continuous distillation with striping gas and its application the physical refining of edible oils
León-Camacho, Manuel,Bada, J. C.,Prieto González, Ma. M.,Graciani Constante, E.
Grasas y Aceites , 2009, DOI: 10.3989/gya.021309
Abstract: The influence of the free fatty acid concentration in the gas inside the continuous deodorizer in continuous physical refining was studied and a hypothesis was formed to explain the results: In a continuous process of deacidification by distillation of free fatty acids at low pressure (2 - 3 mbar), high temperature (180 – 260 oC), with stripping gas, initial free fatty acid content of oil ≤ 7.4% w/w and similar temperature for both the gas distillate inside the continuous deodorizer and the oil, in the equilibrium the ratio between the free fatty acid content of the deacidified oil and the concentration of free fatty acids in the gas inside the continuous deodorizer is constant. This hypothesis is submitted to discussion. Se estudia la influencia de la concentración en ácidos grasos libres en el gas de arrastre en la cabeza del desodorizador durante la refinación física en continuo, y se establece una hipótesis para explicar los resultados: En un proceso continuo de desacidificación por destilación de ácidos grasos a baja presión (2 - 3 mbar), alta temperatura (180 – 265oC), con arrastre de vapor, con igual temperatura para los gases en la cabeza del desodorizador y para el aceite, aplicado a aceites con una acidez inicial ≤ 7,4 % peso/peso, en el equilibrio se cumple que la relación entre la concentración en ácidos grasos libres en el aceite desodorizado y la concentración en ácidos grasos libres en el gas situado en la cabeza del desodorizador es constante. Esta hipótesis se somete a discusión.
Programa de prevención y control de la transmisión vertical del VIH en Cuba: Enero de 1986 - diciembre de 2007 Prevention and control of vertical HIV transmission program in Cuba: January 1986 - December 2007
Ida González N,Manuel Díaz J,Denis Verdasquera C,Jorge Pérez á
Revista chilena de infectología , 2010,
Abstract: La epidemia del VIH/SIDA sigue aumentando significativamente a pesar de las estrategias desarrolladas, incluyendo el desarrollo de la terapia anti-retroviral (TARV) altamente activa. Una de las poblaciones vulnerables a esta infección es los hijos de madres con infección por VIH, que no sólo están expuestos a la infección sino también a quedar huérfanos. En Cuba, desde el a o 1986 se implementó un programa de prevención y control que tiene entre sus objetivos disminuir la transmisión vertical (TV) del VIH. En este estudio se analizaron los 314 ni os nacidos de madres infectadas por VIH/SIDA desde el 1o de enero de 1986 al 31 de diciembre de 2007 en las diferentes maternidades del país, con el objetivo de determinar, mediante un estudio de corte transversal, la relación entre el cumplimiento de las medidas implantadas por el programa de prevención y la TV de la enfermedad. De los 314 ni os nacidos, 248 tenían los estudios concluidos estando 32 ni os infectados, 216 no infectados por el VIH y 66 ni os se encontraban aún en estudio. La mortalidad por causas relacionadas al SIDA fue del 31,2%, y 60% de ellos fallecieron antes de arribar al primer a o de vida. La tasa de TV se redujo considerablemente (de 50,0 a 14,6%) a partir de la instauración del parto por cesárea como medida profiláctica dentro del programa de control y 99 mujeres tuvieron 2,2% de TV cuando se cumplieron las últimas medidas del programa. La eficacia de la combinación del parto por cesárea y la administración de TARV fue de 95,2%. Se concluyó que el programa de prevención y control del VIH/SIDA con su componente materno infantil y las distintas medidas que se le han ido adicionando ha sido efectivo en la reducción de la TV comportándose conforme a lo descrito internacionalmente. The HIV/AIDS epidemic continues to increase in spite of the strategies developed, including the use of HAART. One of the vulnerable populations is the child of HIV+ mothers. In Cuba, a prevention and control program of HIV infection was implemented in 1986 and one of the key aims was to reduce perinatal infection. In this study, the medical records of all 314 children born to HIV/AIDS positive mothers between January 1986 to December 2007 are described. Our aim was to determine the relationship between Program compliance and prevention of vertical transmission (VT). A total of 248/314 infants completed a full virological evaluation at the time of this report 32 (12.9%) were HIV-infected. In these 32 children, mortality due to AIDS related events was 31.2%, of which 60% died before their first year of life. VT rat
Cirugía de revascularización miocárdica versus angioplastía coronaria con stent en enfermedad de tres vasos y/o tronco común izquierdo en diabéticos: meta-análisis de estudios aleatorios Meta-analysis of coronary artery bypass surgery compared to percutaneous transluminal angioplasty with stent in diabetic patients
Andrés Jadue T,Roberto González L,Manuel J Irarrázabal LL
Revista médica de Chile , 2012,
Abstract: Background: Diabetic patients are a group of primary interest in the study of myocardial revascularization. Aim: To compare coronary artery bypass grafting surgery (CABG) and percutaneous angioplasty with stents (PCI-S) in diabetic patients with coronary three-vessel or left main coronary artery disease. Material and Methods: Meta-analysis of MEDLINE randomized controlled studies comparing CABG and PCI-S in diabetic patients. The primary outcome measure was major adverse cardiovascular events (MACCE), death, myocardial infarction, cerebrovascular accident (CVA) and coronary re-intervention. Secondary outcomes were the individual components of MACCE. Results: Three studies comparing CABG and PCI-S met the inclusion criteria. One thousand sixty two patients were studied: 565 in the CABG group and 597 in the PCI-S group. At one year follow up MACCE occurred in 24.9 and 12.7% of patients in PCI-S and CABG groups, respectively (Odds ratio (OR) 2.27; 95% confidence intervals (CI) 1.66-3.09). There were no differences in death or myocardial infarction. Strokes were less common in the PCI-S group (OR 0.25, 95% CI0.09-0.68) and coronary re-intervention was required with higher frequency in the PCI-S group (OR 5.32, 95% CI 3.27-8.67). Conclusions: In diabetic patients with three-vessel coronary disease or left main coronary artery, revascularization with CABG had significantly less MACCE at one year than those treated with PCI-S. Stroke frequency was higher in CABG, coronary re-intervention was higher in PCI-S. These results must be interpreted cautiously.
Nonlinear dynamics of atoms in a crossed optical dipole trap
Rosario González-Férez,Manuel I?arrea,J. Pablo Salas,Peter Schmelcher
Physics , 2014, DOI: 10.1103/PhysRevE.90.062919
Abstract: We explore the classical dynamics of atoms in an optical dipole trap formed by two identical Gaussian beams propagating in perpendicular directions. The phase space is a mixture of regular and chaotic orbits, the later becoming dominant as the energy of the atoms increases. The trapping capabilities of these perpendicular Gaussian beams are investigated by considering an atomic ensemble in free motion. After a sudden turn on of the dipole trap, a certain fraction of atoms in the ensemble remains trapped. The majority of these trapped atoms has energies larger than the escape channels, which can be explained by the existence of regular and chaotic orbits with very long escape times.
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