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Search Results: 1 - 10 of 139443 matches for " Nineb; Vásquez Q "
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RELACIóN ENTRE ESTADO NUTRICIONAL Y SUE O EN ESCOLARES DE LA COMUNA DE SAN MIGUEL, SANTIAGO, CHILE RELATIONSHIP BETWEEN NUTRITIONAL STATUS AND SLEEP IN SCHOOL CHILDREN FROM THE SAN MIGUEL COMMUNE, SANTIAGO, CHILE
Samuel Durán A,Nineb Fuentes de la C,Stephanie Vásquez Q,Gustavo Cediel G
Revista Chilena de Nutricíon , 2012,
Abstract: Objetivo: Determinar si existe asociación entre una menor cantidad de horas de sue o y la obesidad en escolares entre 5 y 7 a os. Métodos: Se estudiaron 155 escolares de primer y segundo a o básico de las escuelas municipales de la comuna de San Miguel, Santiago de Chile, a los cuales se les realizó una evaluación antropométrica y a sus padres una encuesta sobre hábitos de sue o de su hijo(a). Resultados: El 19,3% de los escolares presentó obesidad. El 45,1% de los escolares duerme menos de lo recomendado (<10 horas). Dormir más, hacer ejercicios (OR=0,7 y 0,1, respectivamente) y evitar el consumo de chocolate en la noche (OR=0,346), fueron factores protectores asociado a la presencia de obesidad en la muestra estudiada. En cambio, dormir menos de 10 horas (OR=2,38) es un factor de riesgo para obesidad en la muestra estudiada. Conclusión: La restricción de sue o es un factor de riesgo asociado con la presencia de obesidad en la muestra estudiada. Objective: To determine the association between sleep duration and obesity in school age children between 5 and 7 years old. Methods: One hundred fifty five children from schools in san Miguel town in Santiago of Chile participated in the study. Informed consent was obtained through their parents. Anthropometric variables were measured and a sleep questionnaire was applied. Results: Obesity was present in 193 % of the subjects. 45.1% of the sample slept less than the accepted recommendation for their age (<10 hours). Sleeping more than 10 hours/ night, exercising, and not eating chocolate at night are associated factors for obesity (OR=0.7,0.1 y 0.3 respectively), whereas sleeping less than 10 hours is an associated riskfactor (OR=238). Conclusion: Sleeping less than the accepted recommended amount is an associated risk factor for obesity in this sample.
RELACIóN ENTRE ESTADO NUTRICIONAL Y SUE?O EN ESCOLARES DE LA COMUNA DE SAN MIGUEL, SANTIAGO, CHILE
Durán A,Samuel; Fuentes de la C,Nineb; Vásquez Q,Stephanie; Cediel G,Gustavo; Díaz N,Víctor;
Revista chilena de nutrición , 2012, DOI: 10.4067/S0717-75182012000100003
Abstract: objective: to determine the association between sleep duration and obesity in school age children between 5 and 7 years old. methods: one hundred fifty five children from schools in san miguel town in santiago of chile participated in the study. informed consent was obtained through their parents. anthropometric variables were measured and a sleep questionnaire was applied. results: obesity was present in 193 % of the subjects. 45.1% of the sample slept less than the accepted recommendation for their age (<10 hours). sleeping more than 10 hours/ night, exercising, and not eating chocolate at night are associated factors for obesity (or=0.7,0.1 y 0.3 respectively), whereas sleeping less than 10 hours is an associated riskfactor (or=238). conclusion: sleeping less than the accepted recommended amount is an associated risk factor for obesity in this sample.
EVALUATION OF GENERICINHIBITORS BEHAVIOR FORMULTIPHASE SYSTEMS (STEEL-BRINE-CO2/H2S) BYUSING ELECTROCHEMICAL TECHNIQUES
Pe?a B,Darío-Yesid; Vásquez Q,Custodio; Forero B,Adriana;
CT&F - Ciencia, Tecnología y Futuro , 2007,
Abstract: one of the main ways to inhibit the corrosion is the adsorption of organic compounds on the surface of a metal. this study reports the behavior of six different organic inhibitors in a system carbon steel aisi-sae1020/brine 3%w of nacl/ gas mixture of 6% volume of co2/10 ppm of h2s/ hydrocarbon. two primary amines with sixteen and eighteen atoms of carbon were used, a secondary amine with twenty atoms and three carboxylic acids of sixteen, eighteen and twenty carbon atoms. linear polarization resistance measurements were used, along with tafel extrapolation and electrochemical impedances to assess the influence of temperature, velocity of fluid, inhibitor concentration and concentration of oleic phase on the inhibition efficiency in the electrode of rotational cylinder, ecr. activation and adsorption energies were calculated for the processes of corrosion in the system; according to the values derived, it was possible to define the system brine/co2/h2s/ inhibitor, as a process with mixed control, where the phenomenon of mass transfer and that of charge transfer are in competition and the values obtained for the energy of adsorption of gibbs, allowed checking that these compounds showed a chemical adsorption on the metallic surface. under critical testing conditions (4 m/s, 59oc or 332,15k) the amines present a better efficiency than carboxylic acids, thus complying with the electro-negativity theory applied to inhibitors. it was then possible to establish by the results obtained for the with hydrocarbon cuts tests, that this parameter adversely affects the percentage efficiency of the inhibitor.
Electrochemical behaviour of carbon steel in oil (kerosene) in water emulsion in stagnation conditions
Pe?a Ballesteros,Darío Yesid; Retamoso R,Clemente; Vásquez Q,Custodio;
Revista Técnica de la Facultad de Ingeniería Universidad del Zulia , 2002,
Abstract: oil in water emulsions, which contain water as a continuous phase, show good conditions to allow a flow of electric current. therefore, the corrosion process may be promoted for this kind of system. this study point out results obtained in an interface of kerosene in water emulsion and carbon steel; where the kerosene-water ratio varies from 0 to 70%. the emulsion was in stagnated conditions during the tests. the results were analyzed with the electrochemical impedance technique and the behaviour of the metalemulsion interface represent using equivalent circuits under the different conditions tested. the corrosion type was uniform without any evidence of localized attack due to kerosene contents.
Miocardiopatía hipoclacémica secundaria a hipoparatiroidismo postiroidectomía: Caso clínico
Lam E,José; Maraga?o L,Patricio; Lépez Q,Bárbara; Vásquez N,Loreto;
Revista médica de Chile , 2007, DOI: 10.4067/S0034-98872007000300011
Abstract: calcium plays a central role in ventricular function. we report a 37 year-old woman with chronic hypoparathyroidism and hypocalcemia secondary to a thyroidectomy performed when she was 18 years old, as treatment for a graves basedow's disease. she did not have previous cardiac symptoms and rapid progressive congestive heart failure developed after the beginning of levothyroxin supplementation for post operative hypothyroidism. echocardiography revealed severe systolic and diastolic left ventricular dysfunction, mitral and tricuspid valve insufficiency, systolic pulmonary hypertension, left atrial enlargement and pericardial effusion. calcium supplementation in addition to diuretics, captopril and digoxin were followed by rapid clinical improvement. follow up until 18 months showed persistent left ventricular dilatation and systolic dysfunction, with improvement of all the other ecocardiographic findings
Micobacteriosis hepato-esplénica, forma inusual de probable tuberculosis extrapulmonar: Caso clínico y revisión bibliográfica Hepatic-splenic micobacteriosis, unusual form of probable extrapulmonary tuberculosis: Case report and review
Juan Velásquez M,Muschi Szigethi Q,Rita Panace V,Ricardo Morales I
Revista chilena de infectología , 2007,
Abstract: Reportamos el caso de un hombre de 42 a os, seronegativo para VIH, con fiebre de origen desconocido (FOD), asociada a elevación de transaminasas y fosfatasas alcalinas con patrón colestásico e imágenes hepáticas hipodensas en la tomografía axial computada. La biopsia hepática demostró la presencia de granulomas tuberculosos con visualización de un bacilo con alcohol-ácido resistencia. El cuadro respondió al tratamiento con fármacos antituberculosos presentando caída de curva febril, mejoría del estado general y normalización de parámetros de laboratorio We report a 42 years old HIV negative male admitted for fever of unknown origin. Initial laboratory evaluation showed elevated hepatic transaminases and alkaline phosphatase and an hipodense hepatic imagen was visualized in the CT scan. Hepatic biopsy demonstrated tuberculous granulomas and alcohol fast acid rods with Ziehl Neelsen stain. Anti-tuberculous treatment resulted in resolution of fever, improvement of general condition and normalization of laboratory parameters
Miocardiopatía hipoclacémica secundaria a hipoparatiroidismo postiroidectomía: Caso clínico Hypocalcemic cardiomyopathy secondary to hypoparathyroidism after a thyroidectomy: Report of one case
José Lam E,Patricio Maraga?o L,Bárbara Lépez Q,Loreto Vásquez N
Revista médica de Chile , 2007,
Abstract: Calcium plays a central role in ventricular function. We report a 37 year-old woman with chronic hypoparathyroidism and hypocalcemia secondary to a thyroidectomy performed when she was 18 years old, as treatment for a Graves Basedow's disease. She did not have previous cardiac symptoms and rapid progressive congestive heart failure developed after the beginning of levothyroxin supplementation for post operative hypothyroidism. Echocardiography revealed severe systolic and diastolic left ventricular dysfunction, mitral and tricuspid valve insufficiency, systolic pulmonary hypertension, left atrial enlargement and pericardial effusion. Calcium supplementation in addition to diuretics, captopril and digoxin were followed by rapid clinical improvement. Follow up until 18 months showed persistent left ventricular dilatation and systolic dysfunction, with improvement of all the other ecocardiographic findings
EVALUATION OF GENERICINHIBITORS BEHAVIOR FORMULTIPHASE SYSTEMS (STEEL-BRINE-CO2/H2S) BYUSING ELECTROCHEMICAL TECHNIQUES Evaluación del compotamiento de inhibidores genéricos para sistemas multifásicos (acero-salmuera-CO2/H2S) por medio de técnicas electroquímicas
Darío-Yesid Pe?a B,Custodio Vásquez Q,Adriana Forero B
CT&F - Ciencia, Tecnología y Futuro , 2007,
Abstract: One of the main ways to inhibit the corrosion is the adsorption of organic compounds on the surface of a metal. This study reports the behavior of six different organic inhibitors in a system carbon steel AISI-SAE1020/brine 3%w of NaCl/ gas mixture of 6% volume of CO2/10 ppm of H2S/ hydrocarbon. Two primary amines with sixteen and eighteen atoms of carbon were used, a secondary amine with twenty atoms and three carboxylic acids of sixteen, eighteen and twenty carbon atoms. Linear polarization resistance measurements were used, along with Tafel extrapolation and electrochemical impedances to assess the influence of temperature, velocity of fluid, inhibitor concentration and concentration of oleic phase on the inhibition efficiency in the Electrode of Rotational Cylinder, ECR. Activation and adsorption energies were calculated for the processes of corrosion in the system; according to the values derived, it was possible to define the system brine/CO2/H2S/ inhibitor, as a process with mixed control, where the phenomenon of mass transfer and that of charge transfer are in competition and the values obtained for the energy of adsorption of Gibbs, allowed checking that these compounds showed a chemical adsorption on the metallic surface. Under critical testing conditions (4 m/s, 59oC or 332,15K) the amines present a better efficiency than carboxylic acids, thus complying with the electro-negativity theory applied to inhibitors. It was then possible to establish by the results obtained for the with hydrocarbon cuts tests, that this parameter adversely affects the percentage efficiency of the inhibitor. Uno de los principales caminos para la inhibición de la corrosión lo constituye la adsorción de compuestos orgánicos sobre la superficie de un metal. En este estudio se reporta el comportamiento de seis diferentes inhibidores orgánicos en un sistema acero al carbono AISI-SAE 1020/Salmuera al 3%w de NaCl/ mezcla gaseosa de 6% volumen de CO2/10 ppm de H2S/Hidrocarburo. Se utilizaron dos aminas primarias de dieciséis y dieciocho átomos de carbono, una amina secundaria con veinte átomos y tres ácidos carboxílicos de dieciséis, dieciocho y veinte átomos de carbono. Se emplearon medidas de resistencia a la polarización lineal, extrapolación Tafel e impedancias electroquímicas para evaluar la influencia de la temperatura, velocidad del fluido, concentración de inhibidor y concentración de la fase oleica en la eficiencia de inhibición en el Electrodo de Cilindro Rotatorio (ECR). Se calcularon las energías de activación y adsorción para los procesos de corrosión en el si
Comportamiento electroquímico de recubrimientos Ca - P obtenidos mediante anodizado por plasma químico (APQ) tratados térmicamente
Jennifer Cuesta,Hugo Armando Estupi?án,Darío Yesid Pe?a B.,Custodio Vásquez Q.
Scientia Et Technica , 2007,
Abstract: Los fosfatos de calcio (CaP) se utilizan como recubrimientos bioactivos debido a que aumentan la oseointegración de las superficies de las prótesis. El anodizado por plasma químico (APQ) genera recubrimientos de TiO2 y CaP, amorfos y cristalinos. Un tratamiento térmico de cristalización disminuye el porcentaje de fases amorfas presentes en el recubrimiento. En este trabajo se evaluó por Espectroscopía de Impedancia Electroquímica (EIS), recubrimientos de fosfatos de calcio, aplicados por APQ, sobre un substrato de Ti6Al4V ELI. Se encontró que un tratamiento térmico de cristalización entre 400oC y 800oC, aumenta la cristalinidad del recubrimiento y disminuye su velocidad de degradación.
Headwaters Deforestation for Cattle Pastures in the Andes of Colombia and Its Implications for Soils Properties and Hydrological Dynamic  [PDF]
Guillermo Vásquez-Velásquez
Open Journal of Forestry (OJF) , 2016, DOI: 10.4236/ojf.2016.65027
Abstract: Deforestation of headwater in the Andes of Colombia is a historical process that has its origins in pre-Hispanic communities and in nineteenth and twentieth centuries, intensified by settlers and farmers. These lands have been intended mainly to pasture cattle. Soil compaction, caused by the trampling of cattle, was evaluated in soils derived from volcanic ash (Andisols), with reference to values found for variables in undisturbed natural forests in the same region. The compared parameters were bulk density (Db), total porosity (α), soil resistance to penetration (Rp) and pore size distribution, analyzed by water retention curves (WRC). The grazed soils had significant differences with respect to the natural forest reference values: Db was 53.7% higher, α was reduced by 11.0% and Rp in the first 7.5 cm of the top soil was more than double, with an average increase of 275.2 to 527.2 kPa. The analysis indicated that compacted soils had relatively uniform reduction in distribution of macro, meso and micropores. It was concluded that deforestation followed by pasture land destination in steep headwaters generates significant compaction processes that can affect the infiltration, percolation and soil water storage, which would have important hydrological implications: augmentation of surface runoff and soil erosion, decreased the base flow and increased direct runoff. For this reasons, it is considered that forest restoration of headwaters is important for the maintenance of hydrological functions of large river systems.
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