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Search Results: 1 - 10 of 328854 matches for " Salvador Sánchez-Carrillo "
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Identification of Mangrove Areas by Remote Sensing: The ROC Curve Technique Applied to the Northwestern Mexico Coastal Zone Using Landsat Imagery
Luis C. Alatorre,Raquel Sánchez-Andrés,Santos Cirujano,Santiago Beguería,Salvador Sánchez-Carrillo
Remote Sensing , 2011, DOI: 10.3390/rs3081568
Abstract: In remote sensing, traditional methodologies for image classification consider the spectral values of a pixel in different image bands. More recently, classification methods have used neighboring pixels to provide more information. In the present study, we used these more advanced techniques to discriminate between mangrove and non?mangrove regions in the Gulf of California of northwestern Mexico. A maximum likelihood algorithm was used to obtain a spectral distance map of the vegetation signature characteristic of mangrove areas. Receiver operating characteristic (ROC) curve analysis was applied to this map to improve classification. Two classification thresholds were set to determine mangrove and non-mangrove areas, and two performance statistics (sensitivity and specificity) were calculated to express the uncertainty (errors of omission and commission) associated with the two maps. The surface area of the mangrove category obtained by maximum likelihood classification was slightly higher than that obtained from the land cover map generated by the ROC curve, but with the difference of these areas to have a high level of accuracy in the prediction of the model. This suggests a considerable degree of uncertainty in the spectral signatures of pixels that distinguish mangrove forest from other land cover categories.
Inferring the Relative Resilience of Alternative States
David G. Angeler, Craig R. Allen, Carmen Rojo, Miguel Alvarez-Cobelas, María A. Rodrigo, Salvador Sánchez-Carrillo
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0077338
Abstract: Ecological systems may occur in alternative states that differ in ecological structures, functions and processes. Resilience is the measure of disturbance an ecological system can absorb before changing states. However, how the intrinsic structures and processes of systems that characterize their states affects their resilience remains unclear. We analyzed time series of phytoplankton communities at three sites in a floodplain in central Spain to assess the dominant frequencies or “temporal scales” in community dynamics and compared the patterns between a wet and a dry alternative state. The identified frequencies and cross-scale structures are expected to arise from positive feedbacks that are thought to reinforce processes in alternative states of ecological systems and regulate emergent phenomena such as resilience. Our analyses show a higher species richness and diversity but lower evenness in the dry state. Time series modeling revealed a decrease in the importance of short-term variability in the communities, suggesting that community dynamics slowed down in the dry relative to the wet state. The number of temporal scales at which community dynamics manifested, and the explanatory power of time series models, was lower in the dry state. The higher diversity, reduced number of temporal scales and the lower explanatory power of time series models suggest that species dynamics tended to be more stochastic in the dry state. From a resilience perspective our results highlight a paradox: increasing species richness may not necessarily enhance resilience. The loss of cross-scale structure (i.e. the lower number of temporal scales) in community dynamics across sites suggests that resilience erodes during drought. Phytoplankton communities in the dry state are therefore likely less resilient than in the wet state. Our case study demonstrates the potential of time series modeling to assess attributes that mediate resilience. The approach is useful for assessing resilience of alternative states across ecological and other complex systems.
Imidoyl Radicals for the Synthesis of Chromenoquinolines and Naphthyridines  [PDF]
Karen C. Vizcaíno-Escobedo, J. Adrián Sánchez-Carrillo, Martha Albores-Velasco
International Journal of Organic Chemistry (IJOC) , 2018, DOI: 10.4236/ijoc.2018.83024
Abstract: The stability of imidoyl radicals prepared from 2-(2-alkenyloxy)-phenyl selenoimidates and 2-(2-allylamino)-phenyl selenoimidates and their intramolecular free radical cyclization through the slow addition of tri-N-butyltin hydride and AIBN to obtain 4-chromanones and 4-quinolones were studied. The extension of the methodology to N-phenyl substituted imidoyl selenoates produced tandem cyclizations of the imidoyl radical with the allyl substituent, followed for a second cyclization of the intermediate radical with the aromatic substituent to produce dihydro-chromenoquinolines or tetrahy-dro-dibenzonaphtyridines. Further oxidation with DDQ produced: 6H-chromeno [4,3,b] quinoline and 7-methyl-6H-chromenoquinoline from 2-alkenylamino-phenylbenzamide and 5,6-dihydro-dibenzo [b,h][1,6] naphthyridine and 5,6-dihydro-7-methyl-dibenzo [b,h][1,6] naphthyridine from 2-2-(alkylamino)-N-phenylbenzamides. The cyclization of 2-(N,N-di-prop-2.enylamino)-N-phenylnicotinamide selenoate obtained from 2-aminonicotinic acid, produced 5,6-dihidro-benzo[b]pyrido2,3-h] [1,6] naphthyridine.
Aplicación de la perspectiva de género en artículos publicados en cuatro revistas nacionales de salud, México, 2000-2003
Cerón-Mireles Prudencia,Sánchez-Carrillo Constanza I.,Robledo-Vera Cecilia,Zolezzi Aurora del Río
Salud Pública de México , 2006,
Abstract: OBJETIVO: Elaborar un diagnóstico sobre la aplicación de la perspectiva de género en el campo de la investigación en salud en cuatro revistas mexicanas de los institutos nacionales de salud. MATERIAL Y MéTODOS: Se revisaron 999 artículos publicados en cuatro revistas científicas (2000-2003), con dos niveles de análisis: a) desagregación de datos por sexo, que permite describir las diferencias entre mujeres y hombres; y b) análisis de estas diferencias desde la perspectiva de género. RESULTADOS: De los artículos revisados, 25.4% desagregó sus resultados por sexo, de los cuales el mayor porcentaje se publicó en Salud Pública de México (48.8%) y el menor en la Revista de Investigación Clínica (16.1%). Solamente 4.2% de los artículos aplicó la perspectiva de género, y los temas mayormente abordados fueron las adicciones, el comportamiento sexual y la violencia. CONCLUSIONES: Este es el primer estudio en México que evalúa la aplicación de la perspectiva de género en la investigación en salud. Al igual que en otros países, es baja la proporción de artículos que analizan las diferencias por sexo y aplican la perspectiva de género. Esto destaca la importancia de promover la investigación interdisciplinaria que ayude a comprender los orígenes biológicos y sociales, o la combinación de ambos, que determinan la salud desigual entre mujeres y hombres.
Structural characterization of the C2 domains of classical isozymes of protein kinase C and novel protein kinase Cε by using infrared spectroscopy
Senena Corbalán-García,Josefa García-García,M. Susana Sánchez-Carrillo,Juan C. Gómez-Fernández
Spectroscopy: An International Journal , 2003, DOI: 10.1155/2003/361563
Abstract: The amide I regions in the original infrared spectra of PKCα-C2 in the Ca2
Amiloidosis hepática como causa de colestasis severa intrahepática
Gavilán,J. C.; Bermúdez,F. J.; Márquez,A.; Sánchez-Carrillo,J. J.; González-Santos,P.;
Anales de Medicina Interna , 2003, DOI: 10.4321/S0212-71992003000100006
Abstract: the liver is frequently involved by amyloidosis, but hyperbilirubinemia and liver failure are uncommon features. a mild elevation of the serum alkaline phosphatase value and, less frequently, hepatomegaly are the most common findings. usually the patients have no symptoms related with the liver involvement; the clinical manifestation and the long term prognosis depends on the renal and cardiac disease. we report an unusual clinical presentation of primary amyloidosis in a previously asymptomatic 65 years old woman who was admitted to the hospital because of ictericia and ascitis mimicking a drug induced acute hepatic failure.
Condiciones de trabajo materno y bajo peso al nacer en la Ciudad de México
Salud Pública de México , 1997, DOI: 10.1590/S0036-36341997000100002
Abstract: objective. to study the association between maternal working conditions and low birth-weight in mexico city. material and methods. interviews of 2 623 workers who gave birth in mexico city hospitals during 1992 were analyzed. information on the main biologic and social factors associated to low birth-weight was registered. occupational stress was determined with the instrument designed by karasek. logistic regression models to evaluate the relationship between working conditions and low birth-weight were used, controlling by confounding variables. results. low birth-weight was more frequent in workers with working periods of more than 50 h/week (or= 1.6; 95% ci= 1.17, 2.28) and with problems at work (or= 1.5; 95% ci= 1.0, 2.25). lack of tangible social support was identified as a risk factor for low birth-weight (or= 1.7; 95% ci= 1.20, 2.33). preventive working measures such as changes in tasks, shortening of working hours and leaves of absence due to illness did not show a beneficial effects on birth-weight, except for the maternity leave of absence. mothers with no right to this had a 2.2 higher probability of giving birth to low weight children (95% ci= 1.66, 2.93). conclusions. these results emphasize the importance of identifying the occupational risk factors during pregnancy.
Condiciones de trabajo materno y bajo peso al nacer en la Ciudad de México
Salud Pública de México , 1997,
Abstract: Objetivo. Estudiar la asociación entre condiciones de trabajo materno y bajo peso al nacer en la Ciudad de México. Material y métodos. Se encuestaron 2 623 trabajadoras que atendieron sus partos en tres grandes hospitales de la Ciudad de México en 1992. Se obtuvo información sobre los principales factores biológicos y sociales que se asocian al bajo peso al nacer; asimismo, se determinó el estrés ocupacional utilizando el instrumento desarrollado por Karasek. Se utilizaron modelos de regresión logística para evaluar la relación de las condiciones de trabajo con el bajo peso al nacer, controlando por variables confusoras. Resultados. El bajo peso al nacer fue más alto en trabajadoras con jornadas mayores a 50 horas semanales (RM= 1.6; IC= 1.17, 2.28) y con conflictos laborales (RM= 1.5; IC= 1.0, 2.25). La falta de apoyo social tangible fue identificado como un factor de riesgo de bajo peso al nacer (RM= 1.7; IC= 1.20, 2.33). Las medidas preventivas laborales como el cambio de tareas, disminución de la jornada y las salidas por enfermedad no mostraron un efecto benéfico en el peso al nacer, a excepción de la licencia de maternidad; las madres que no la tuvieron mostraron una probabilidad 2.2 veces mayor para bajo peso al nacer (IC= 1.66, 2.93). Conclusiones. Estos hallazgos resaltan la importancia de identificar los factores de riesgo ocupacional en el embarazo..
Aplicación de la perspectiva de género en artículos publicados en cuatro revistas nacionales de salud, México, 2000-2003
Cerón-Mireles,Prudencia; Sánchez-Carrillo,Constanza I.; Robledo-Vera,Cecilia; Zolezzi,Aurora del Río; Pedrosa-Islas,Laura; Reyes-Zapata,Hilda; Cerón-Mireles,Berta; Ordaz-Hernández,Guadalupe; Olaiz-Fernández,Gustavo Adolfo;
Salud Pública de México , 2006, DOI: 10.1590/S0036-36342006000400008
Abstract: objective: the objective of this study was to determine the application of gender perspective in public health papers in four journals published by the mexican national health institutes. material and methods: a total of 999 papers published in the four journals between 2000 and 2003 was reviewed. two levels of analysis were considered: a) data presented by sex, providing description of differences between women and men, and b) the analysis of these differences from gender perspective. results: one quarter (25.4%) of the articles described results by sex. the largest percentage was published in salud pública de méxico (48.8%) and the smallest in revista de investigación clínica (16.1%). gender perspective was used in only 4.2% of papers; of these, drug addictions, health behaviour and violence were the topics that occurred most frequently. conclusions: this is the first study to assess the application of gender perspective in mexican health articles. similarly to other countries, a very small percentage of authors analyzed sex differences, and a smaller proportion applied gender perspective. results demonstrate the importance of promoting interdisciplinary research that may promote the elucidation of health inequalities between men and women.
Modelo asistencial integrador en salud mental infantojuvenil
Salvador Sánchez,Isabel;
Revista de la Asociación Espa?ola de Neuropsiquiatría , 2001, DOI: 10.4321/S0211-57352001000400009
Abstract: the attention of children and teenagers mental health has as an main axis, the therapeutic intervention. the election of such intervention is affected by: -the population who our intervention is aimed at. children and teenagers are fellows with an integral biopsychosocial entity in permanent evolution and interaction with their familiar and social environment. this implies that their expression psychopathology and clinic are specific. -the therapeutics resources of the children and teenagers mental health team itself. -the characteristics and community resources of the territory which the children and teenagers mental health team is registered. we present the organisation model of the assistance to the infant-junior mental health inside a mental health unit (general) of the insalud in the manacor′s sector (mallorca island) and that take in nearly 110.000 habitants. the interdisciplinary and interinstitutional coordination between all the sectors involved in the life of the child and teenager is basic to be able to carry out an assistance with a minimal quality.
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