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Search Results: 1 - 10 of 514359 matches for " David Efraín; Sánchez-Román "
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El subregistro potencial de accidentes de trabajo en el Instituto Mexicano del Seguro Social
Salinas-Tovar,José Santiago; López-Rojas,Pablo; Soto-Navarro,María Oralia; Caudillo-Araujo,David Efraín; Sánchez-Román,Francisco Raúl; Borja-Aburto,Víctor Hugo;
Salud Pública de México , 2004, DOI: 10.1590/S0036-36342004000300009
Abstract: objective: to assess the potential under-registration of work-related accidents in the mexican institute of social security. material and methods: a countrywide cross-sectional study was carried out with information collected from 27 district offices of the mexican institute of social security (miss), on workers seen at miss emergency rooms during november 2001 because of a probable accident at work. we compared these reports to official records of work-related accidents to estimate the proportion of incomplete reports. data analysis consisted of descriptive statistics for each variable; the annual estimation of incomplete reporting proportions was made by multiplying by twelve months; 95% confidence intervals were estimated using poisson's exact method for a proportion. results: data from 27 out of 37 miss district offices revealed that 7 211 cases were not recognized as work accidents, accounting for an underestimation of 26.3%, ranging between 0 and 68% among the different district offices. the accidents that were most frequently left unregistered were mild and blunt injuries. conclusions: under-registration can affect worker compensation plans and the financial balance of the institution's occupational risk insurance. research is needed to investigate and eliminate the causes of under-registration. employers, the industry, and health institutions should be involved in this effort
The Case of the Lacking Carbonates and the Emergence of Early Life on Mars
David Carlos Fernández-Remolar,Mónica Sánchez-Román,Ricardo Amils
Sustainability , 2010, DOI: 10.3390/su2082541
Abstract: The mineralogical characterization of Mars by different exploration missions, provides a new image of the earliest conditions that prevailed on the planet surface. The detection of extensive deposits of phyllosillicates has been considered to be as a result of the production of hydrated silicates through alteration and precipitation under neutral to sub-alkaline conditions. Although extensive deposits of carbonates should precipitate beneath a thick CO2-bearing atmosphere, only a few outcrops of Mg-rich carbonates have been detected on Mars. Paradoxically those carbonates occur in association with geological units exposed to acidic paleoenvironments. Given such geochemical conditions on Earth, the carbon cycle is intimately associated with life, then, we can assume that the presence or absence of microbial communities should have impacted the distribution of those carbonate compounds on Mars. In this paper, we suggest three potential geobiological scenarios to explain how the emergence of life on Mars would have impacted the carbon cycle and, hence, the formation of carbonates on a planetary scale.
Toxocariasis ocular: A propósito de un caso
Gómez,L.; Rueda,T.; Pulido,C.; Sánchez-Román,J.;
Archivos de la Sociedad Espa?ola de Oftalmología , 2008, DOI: 10.4321/S0365-66912008000100010
Abstract: case report: we present the case of a seven-year-old male with ocular toxocariasis. the fundus of the eye showed a vitritis, as a result of which the retina could not be seen. following treatment with systemic corticosteroids the condition evolved favorably. however, due to a papillary and peripheral granuloma that raised the macula, a vitrectomy was performed which stabilized the process. discussion: ocular toxocariasis is not common in developed countries. the diagnosis is based on funduscopic aspects, serology and igg positivity of the vitreous. in relation to treatment, as the use of anthelminthics therapy is controversial, the use of corticosteroids and vitrectomy is recommended.
Toxocariasis ocular: A propósito de un caso Ocular toxocariasis: A case report
L. Gómez,T. Rueda,C. Pulido,J. Sánchez-Román
Archivos de la Sociedad Espa?ola de Oftalmología , 2008,
Abstract: Caso clínico: Paciente de 7 a os diagnosticado de toxocariasis ocular. El fondo de ojo mostraba una vitritis que no permitía ver la retina. Se instauró tratamiento con corticoides, evolucionando favorablemente, pero existía un granuloma papilar y periférico que levantaba la mácula por lo que se realizó una vitrectomía consiguiéndose la estabilización del proceso. Discusión: La Toxocariasis ocular es rara en los países desarrollados. El diagnóstico está basado en el aspecto oftalmoscópico, la serología y la Ig G + en vítreo. En cuanto al tratamiento sigue siendo controvertido el uso de antihelmínticos y aceptado el uso de corticoides y la vitrectomía. Case report: We present the case of a seven-year-old male with ocular toxocariasis. The fundus of the eye showed a vitritis, as a result of which the retina could not be seen. Following treatment with systemic corticosteroids the condition evolved favorably. However, due to a papillary and peripheral granuloma that raised the macula, a vitrectomy was performed which stabilized the process. Discussion: Ocular toxocariasis is not common in developed countries. The diagnosis is based on funduscopic aspects, serology and IgG positivity of the vitreous. In relation to treatment, as the use of anthelminthics therapy is controversial, the use of corticosteroids and vitrectomy is recommended.
Situa??o dos recursos hídricos nas bacias hidrográficas dos rios Piracicaba, Capivari e Jundiaí utilizando modelo desenvolvido em dinamica de sistemas
Sánchez-Román, Rodrigo M.;Folegatti, Marcos V.;Orellana-González, Alba M. G.;
Engenharia Agrícola , 2009, DOI: 10.1590/S0100-69162009000400008
Abstract: using a dynamic systems model specifically developed for piracicaba, capivari and jundiaí river water basins (bh-pcj) as a tool to help to analyze water resources management alternatives for policy makers and decision takers, five simulations for 50 years timeframe were performed. the model estimates water supply and demand, as well as wastewater generation from the consumers at bh-pcj. a run was performed using mean precipitation value constant, and keeping the actual water supply and demand rates, the "business as usual" scenario. under these considerations, it is expected an increment of about ~76% on water demand, that ~39% of available water volume will come from wastewater reuse, and that waste load increases to ~91%. falkenmark index will change from 1,403 m3 person-1 year-1 in 2004, to 734 m3 p-1 year-1 by 2054, and the sustainability index from 0.44 to 0.20. another four simulations were performed by affecting the annual precipitation by 90 and 110%; considering an ecological flow equal to 30% of the mean daily flow; and keeping the same rates for all other factors except for ecological flow and household water consumption. all of them showed a tendency to a water crisis in the near future at bh-pcj.
Ense?anza de medicina del trabajo en el pregrado de las escuelas de medicina en México
Sánchez-Román,Francisco Raúl; Medina-Figueroa,Alda María; Rangel-Zertuche,Ricardo Alfonso; Sánchez-Ramos,Apolinar;
Salud Pública de México , 2009, DOI: 10.1590/S0036-36342009000200004
Abstract: objective: to analyze the current situation of teaching occupational medicine (om) in academic programs and medical schools in mexico. material and methods: a descriptive survey was conducted and schools were identified through the main directories of medical schools. for the analysis of information descriptive and inferential statistics were used. results: a total of 75 medical schools were identified. in 39 (52%) the subject is mandatory, with a predominance in public schools (p< 0.02). among the schools that offer the subject, only 15 (38%) have professors specialized in om. conclusions: disparity in teaching basic aspects of om in medical schools explains the little development and social and professional recognition of the specialty; it also highlights serious problems for public health, derived from the lack of prevention of risks in work environments.
Minimiza??o da eros?o em fun??o do tamanho e localiza??o das áreas de floresta no contexto do programa "conservador das águas"
Zolin, Cornélio Alberto;Folegatti, Marcos Vinícius;Mingoti, Rafael;Sánchez-Román, Rodrigo Máximo;Paulino, Janaina;Gonzáles, Alba Maria Guadalupe Orellana;
Revista Brasileira de Ciência do Solo , 2011, DOI: 10.1590/S0100-06832011000600030
Abstract: as conflicts related to the water use in brazil are increasing, the implementation of policies that can mitigate these problems has become crucial. in this context, the concept of payment for environmental services (pes) has been widely accepted and applied around the world and also in brazil. the municipality of extrema, in the state of minas gerais, was the first in brazil to implement a pes program, known as "conservador das águas". this study aimed to evaluate soil losses in the watershed posses and determine the potential of the pes program to conserve soil in this watershed; moreover, to maximize the soil conservation environmental service for a given forest size and location. therefore, the effectiveness of soil conservation was analyzed in 14 areas with different soil use and forest cover. the geographic information system (sig) and the revised universal soil loss equation (rusle) were used for this purpose. soil losses in the posses watershed were estimated before and after implementing the water conservation program, at 30.63 and 7.06 mg ha-1 year-1, respectively. conservation could be optimized by implementing soil conservation practices on pasture and by optimizing the location of forest areas.
Dynamic systems approach assess and manage water resources in river basins
Sánchez-Román, Rodrigo Máximo;Folegatti, Marcos Vinicius;Orellana González, Alba María Guadalupe;Silva, Rogério Teixeira da;
Scientia Agricola , 2009, DOI: 10.1590/S0103-90162009000400001
Abstract: the piracicaba, capivari and jundiaí river basins (rb-pcj) are located in the states of minas gerais and s?o paulo, brazil. by 2005, 5.8% of brazil's general national product-gnp was produced there. such economic development has created a huge demand for water resources. the availability of water resources was assessed by running a dynamic systems simulation model to manage these resources in the rb-pcj (wrm-pcj), considering five 50-year simulations. wrm-pcj was developed as a tool to aid the rb-pcj watershed committee. the model computes water supply, demands, and contamination load from several consumers. when considering a business-as-usual scenario, by 2054, water demands will have increased up to 76%, 39% of the available water will come from wastewater reuse, and the contamination load will have increased by 91%. the falkenmark index started at 1403 m3 person-1 year-1 in 2004, ending at 734 m3 p-1 yr-1 in 2054; the xu sustainability index started at 0.44 and ended at 0.20; and keller's river basin development phases started as phase ii, and ended at final phase iii, of augmentation. the three criteria used to evaluate water resources showed that rb-pcj is at a crucial management turning point. the wrm-pcj performed well, and proved to be an excellent tool to assess water resources availability.
Dinamica de sistemas e a modelagem com o uso do programa STELLA dos recursos hídricos da bacia do Rio Preto, afluente do Rio Paracatu DINáMICA DE SISTEMAS Y MODELAJE DE LOS RECURSOS HíDRICOS EN LA CUENCA DEL RíO PRETO, AFLUENTE DEL RíO PARACATU, USANDO EL PROGRAMA STELLA DYNAMIC OF SYSTEMS AND THE MODELLING WITH THE USE STELLA PROGRAM OF THE HYDROLOGIC RESOURCES IN THE RIO PRETO BASIN, PARACATU RIVER TRIBUTARY
Maurício Novaes Souza,Everardo Chartuni Mantovani,Alba Maria Guadalupe Orellana González,Rodrigo Máximo Sánchez-Román
Revista Ibero-Americana de Ciências Ambientais , 2010,
Abstract: A ausência da avalia o das quest es relativas à predi o na implanta o de projetos tem sido uma regra. Neste estudo se buscou representar as inter-rela es existentes das mudan as das classes de uso do solo e suas influências sobre os fatores climáticos e os ecossistemas aquáticos, na bacia hidrográfica do rio Preto, afluente do rio Paracatu. Neste local, onde a vaz o média anual retirada pela ‘Irriga o’ na bacia teve crescimento de 62 vezes no período 1970-1996, gerando uma série de conflitos regionais, tem ocorrido a substitui o da vegeta o nativa ‘Cerrado’ por ‘Cultivo’. A situa o é preocupante quando se verifica pela análise da oferta de água no período 1985-2000, que a ‘Precipita o’ na bacia e as vaz es média e mínima sofreram significativas redu es. A proposta deste trabalho foi desenvolver um modelo de oferta e demanda do uso da água, baseado em princípios de ‘Dinamica de Sistemas’ com o auxílio do software STELLA. Por intermédio da modelagem foi possível expressar graficamente a complexidade dinamica das rela es deste sistema. A calibra o do modelo foi realizada por meio de dados da esta o fluviométrica Porto dos Po es, coletados no período 1985-2000. Com a simula o do modelo, para o período 1995-2060, verificou-se a tendência de redu o de -23,08% na ‘Precipita o’ no Cenário ‘Agronegócio Atual’. La implementación de proyectos, carece por lo general, de mecanismos de evaluación del impacto futuro de los mismos. En este estudio se trató de representar, las interrelaciones que existen entre los cambios en el uso del suelo y la influencia que tienen en los factores climatológicos y en los ecosistemas acuáticos, en la cuenca hidrográfica del rio Preto, afluente del rio Paracatu. En dicha cuenca, el caudal medio anual retirado para la “Irrigación” aumento 62 veces durante el periodo de 1979 a 1996, creando una serie de conflictos a nivel regional. Se ha substituido la vegetación nativa del “Cerrado” por “Cultivos”. La situación se torna crítica cuando se verifica a través del análisis de la oferta de agua para el periodo 1985-2000, que la “Precipitación” en la cuenca y los caudales medios y mínimos sufrieron reducciones significativas. Este trabajo se propuso desarrollar, un modelo de oferta y demanda del uso del agua, fundamentado en los principios de la “Dinámica de Sistemas” con el auxilio del software STELLA. A través del modelaje, fue posible expresar de forma grafica lo compleja que es la dinámica de las relaciones de este sistema. El modelo fue calibrado con datos de la estación pluviométrica Porto dos Po oes, recogidos para el pe
Software STELLA e o comportamento hidrológico na bacia do ribeir o Entre Ribeiros, afluente do rio Paracatu, em cenário de mudan a climática SOFTWARE STELLA Y COMPORTAMIENTO HIDROLOGICO DE LA CUENCA RIBEIR O ENTRE RIBEIROS, AFLUENTE DEL RíO PARACATU EN UN ESCENARIO DE CAMBIO CLIMáTICO SOFTWARE STELLA AND THE hydrologic behavior in the basin of the Entre Ribeiros river, PARACATU RIVER TRIBUTARY, in Scenery of climatic change
Maurício Novaes Souza,Everardo Chaturni Mantovani,Alba Maria Guadalupe Orellana González,Rodrigo Máximo Sánchez-Román
Revista Ibero-Americana de Ciências Ambientais , 2010, DOI: 10.6008/ess2179-6858.2010.001.0003
Abstract: A ocorrência de fen menos meteorológicos e climatológicos extremos se tornou fato. Apesar da ado o de medidas emergenciais, alguns problemas se intensificaram: incremento da concentra o de gases de efeito estufa; diminui o da camada de oz nio; redu o das terras agricultáveis; crescente contamina o dos ecossistemas aquáticos e redu o progressiva dos recursos de água doce. Um dos fatores agravantes dessa situa o se refere à substitui o da vegeta o nativa, realidade da bacia do ribeir o Entre Ribeiros, afluente do rio Paracatu, onde a atividade ‘Irriga o’ apresenta forte incremento. Nessa bacia tem ocorrido a substitui o de ‘Cerrado’ (-47,65%) por ‘Cultivo’ (+198,09%), que diminui a intercepta o da água da chuva, aumenta o escoamento superficial e reduz a infiltra o de água no solo, causando redu o das vaz es médias e mínimas. Nesse estudo, por meio da modelagem baseada em princípios de ‘Dinamica de Sistemas’ e com o uso do software STELLA, simulou-se possíveis efeitos das mudan as climáticas na referida bacia, considerando-se acréscimos de 1oC na temperatura e de 6,9% na precipita o no período 1995-2060. Verificou-se a tendência de uma redu o de -15,16% na ‘Precipita o direta’ e significativas altera es nas taxas evapotranspirométricas para ‘Pasto’ (+33,34%); ‘Cultivo’ (+23,77%); ‘Cerrado’ (+8,54%); e ‘Mata’ (-9,49%). Los fenómenos meteorológicos y climatológicos de carácter extremo, ocurren frecuentemente en la actualidad. A pesar de la adopción de medidas paliativas, ciertos problemas se han intensificado: aumento de la concentración de gases de efecto invernadero, disminución de la capa de ozono, reducción de áreas aptas para la agricultura, ecosistemas acuáticos cada vez más contaminados y la disminución progresiva de los recursos hídricos. Uno de los factores que agravan esta situación, es la substitución constante de la vegetación nativa, que es una realidad evidente en la cuenca de Ribeir o Entre Ribeiros, afluente del rio Paracatu, donde la “Irrigación” viene incrementándose de forma intensa. En esta cuenca se ha substituido el “Cerrado” (-47.65%) por el “Cultivo” (+198.09%), lo cual reduce la intercepción del agua de lluvia, aumenta la escorrentía superficial y disminuye la infiltración del agua en el suelo, causando por tanto, una reducción de los caudales medios y mínimos. En el presente estudio, por medio del modelaje de “Dinámica de Sistemas” y con auxilio del software STELLA, se simularon posibles efectos del cambio climático, en la cuenca antes citada. Se consideró el aumento de 1oC en la temperatura y de 6.9% en la precipi
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