Índices de calidad del agua subterránea para uso agrícola en el Soconusco, Chiapas, México

"In Soconusco, Chiapas, in spite of the high availability of surface water, it is resorting to the use of groundwater. Knowledge about the quality of surface or groundwater used to irrigate crops in that region is low. This paper aims to contribute to the knowledge of the quality of groundwater for agricultural use through the characterization of the spatial variability. Assuming a random spatial distribution of 45 samples which were collected in situ were determined: acidity and alkalinity (pH), electrical conductivity (EC), Total Dissolved Solids (TDS), cations and anions and trace elements; in addition to the agricultural index: Sodium Adsorption Ratio (SAR), Residual Sodium Carbonate (RSC), Soluble Sodium Percentage (SSP), Sodium Percentage (% Na), Kelly Ratio (KR), Magnesium Adsorption Ratio (MAR), Permeability Index (PI), Effective Salinity (ES), Salinity Potential (SP) and Osmotic Potential (OP). In general, SSP, % Na, KR, PI are low, there is only one anomalous point (9) with high values at W of the study area. Similarly, PS, ES, Cl, Na and SAR are low except point 16 and conversely, RSC and pH are high, except at this point located in the center of the study area. The results allow us to infer that the water in that aquifer presents no problems or sodicity toxic ions. In 27 sites sampled values above 250 µmhos/cm were found at 25°C, classified as medium to high risk of salinity, unsuitable for agricultural use. Analysis of the combined effect of the presence of sodium (SAR) and salinity (EC or TDS) shows that 27 of analyzing sites have restricted water medium at very high for use in irrigation.""En el Soconusco, Chiapas, a pesar de la alta disponibilidad de agua superficial, se recurre al uso del agua subterránea. El conocimiento de la calidad del agua superficial o subterránea utilizada para el riego de los cultivos en la región es bajo. Este trabajo contribuye al conocimiento de la calidad del agua subterránea para uso agrícola a través de la caracterización de su variabilidad espacial. Asumiendo una distribución espacial aleatoria, se colectaron 45 muestras, a las que se les determinó: acidez y alcalinidad (pH), conductividad eléctrica (CE), Sólidos Totales Disueltos (TDS), cationes y aniones y oligoelementos; además se determinaron índices agrícolas: Índice de adsorción de sodio (SAR), Carbonato de sodio residual (CSR), Porcentaje de sodio soluble (PSS), Porcentaje de sodio (% Na), Relación de Kelly (RK), Relación de Absorción de Magnesio (RAM), Índice de Permeabilidad (IP), Salinidad Efectiva (SE), Salinidad Potencial (SP) y Potencial Osmótico (OP). En general, el PSS, % Na, RK, IP son bajas, sólo hay un punto anómalo (9) con valores altos en la parte oeste del área de estudio. Del mismo modo, SP, SE, Cl, Na y el RAS son bajos, excepto en el punto 16 y en contraste, CSR y pH son altos, excepto en este punto ubicado en el centro del área de estudio. Los resultados nos permiten inferir que el agua en ese acuífero no presenta problemas de sodicidad y de tóxicos. En 27 sitios se encontraron valores superiores a 250 µm/cm a 25 ° C, clasificados como de riesgo medio a alto de salinidad, es decir inadecuados para uso agrícola. El análisis del efecto combinado de la presencia de sodio (RAS) y salinidad (CE o SDT) muestra que 27 de los sitios analizados presentan restricciones de medias a muy altas para su uso en riego.

Modeling of groundwater flow and water use for San Luis Potosí Valley aquifer system

"Land use changes are currently one of the indisputable factors in the alteration of processes and cycles of the aquifer system in the San Luis Potosí Valley. Due to its importance, is considered indispensable to investigate this detrimental factor of aquifers. The aim of this research is to use a numerical flow model to analyze the impact that land use changes have had on the aquifer. A finite differences numerical model was adapted to the size and hydrological properties of the aquifer system. It consisted of a regular grid with 30 columns and 34 rows with constant spacing of 1000 meters. It has two layers; the first includes the shallow aquifer and the second, the deep aquifer. The initial hydraulic head of the model corresponds to 1986 and was verified for 1995 and 2007. The model shows the development of a drawdown cone (central valley) extending toward the industrial area (southern valley). Piezometric water levels revealed a decrease of 0.6 to 1.6 meters annually during a period from 1977 to 2007. This work demonstrates that it is the consequence of land use changes and of the incessant overall decline in groundwater reserves. Based on the flow model, population growth projections and water use change, the calculated predictions indicate that by 2021, the total established volume of 136 Mm3/year for consume will be reached. The flow model of the San Luis Potosí Valley aquifer system shows a clear effect of the risks associated with aquifer mining.

Metodología y aplicación de atributos sísmicos en la modelación de facies para zonas potencialmente productoras de gas. Área Santa Cruz-Jibacoa, Cuba

Históricamente, la exploración petrolera en Cuba, se ha apoyado en estudios geoquímicos, petrofísicos y de ingeniería de yacimientos en los pozos para caracterizar los intervalos productores de hidrocarburos y la explotación del gas disuelto. El objetivo de este estudio es detectar en esos reservorios, las acumulaciones comerciales de gases húmedos a partir del uso de los atributos sísmicos con la instrumentación de una metodología de trabajo. Se escogieron dos yacimientos que se encuentran en la Franja Norte Petrolera Cubana; el Santa Cruz del Norte (patrón de aprendizaje) y Jibacoa (patrón predictivo). Como objeto se estudió la Formación Vega Alta, secuencia sinorogénica de edad Paleoceno-Eoceno Medio, con gran complejidad litológica, considerada sello regional, pero paradójicamente, con apreciables manifestaciones de hidrocarburos, principalmente de gas. Se realizó un análisis microfacial, fundamentalmente con la información de los cuttings (1921 m), construyéndose un modelo ternario para las rocas clásticas y otro para las carbonatadas y silíceas, con predominio de las primeras. Para obtener información sobre la relación entre las litofacies y los atributos sísmicos, se efectuó un análisis exploratorio de los datos. Se establecieron las firmas sísmicas para cada litotipo y con la aplicación de métodos de minería de datos, se ajustó la capacidad de esos atributos para diferenciar cada litofacies. Fueron discretizados 4130 intervalos patrones en pozos. Para trabajar dentro de un dominio con gran incertidumbre, se empleó un algoritmo geoestadístico de simulación secuencial de indicadores para calcular las probabilidades. Se ejecutó la conversión de atributo sísmico a litofacies, mediante una clasificación supervisada, en una matriz de 350000 celdas (aproximadamente 43750 km3 en total), con los atributos sísmicos seleccionados como significativo y por último se estableció un cálculo de riesgo-recompensa que pronostica el alcance económico de esta estrategia.Historically the Cuban exploration strategy has been characterized by discovering productive oil intervals and to use its associated gas by conventional methods. The objective of this study was to create a methodology to detect reservoirs with free gaseous hydrocarbons contain, by seismic attributes. Were chosen two oilfields located in the Cuban Northern Oil Belt; (main Cuban oil region); Santa Cruz del Norte (learning pattern) and Jibacoa oil fields (predictive pattern). Were studied the Vega Alta Formation, a synogenic sequence of Paleocene-Middle Eocene age, with great lithological complexity and considered as a regional seal, but paradoxically, with significant hydrocarbons presence. A microfacial analysis was carried out, with the information of the cuttings, building a ternary model for clastite rocks and another model for carbonated and siliceous rocks. Were studied 1921 m by cuttings samples, predominantly clastic lithofacies. An exploratory data analysis was carried out, which permitted obtaining information about the unknown relationship between lithofacies and seismic attributes. The seismic signatures of lithofacial classification were determined, and with the assistance of data mining methods were adjusted the seismic attributes to differentiate lithofacies. These were discretized in 4130 standard patterns intervals. Probability values were calculated applying a geostatistics sequential simulation algorithm. The inverse task (conversion of seismic attributes to lithofacies) was executed, through a supervised classification, into a 350000 cells matrix (approximately 43750 km3), with the selected seismic attributes and finally, an exploration risk analysis was calculated for estimate the economic strategy

Risk Factors and Predictive Score for Bacteremic Biliary Tract Infections Due to Enterococcus faecalis and Enterococcus faecium: a Multicenter Cohort Study from the PROBAC Project

Biliary-tract bloodstream infections (BT-BSI) caused by Enterococcus faecalis and E. faecium are associated with inappropriate empirical treatment and worse outcomes compared to other etiologies. The objective of this study was to investigate the risk factors for enterococcal BT-BSI. Patients with BT-BSI from the PROBAC cohort, including consecutive patients with BSI in 26 Spanish hospitals between October 2016 and March 2017, were selected; episodes caused by E. faecalis or E. faecium and other causes were compared. Independent predictors for enterococci were identified by logistic regression, and a predictive score was developed. Eight hundred fifty episodes of BT-BSI were included; 73 (8.5%) were due to target Enterococcus spp. (48 [66%] were E. faecium and 25 [34%] E. faecalis). By multivariate analysis, the variables independently associated with Enterococcus spp. were (OR; 95% confidence interval): cholangiocarcinoma (4.48;1.32 to 15.25), hospital acquisition (3.58;2.11 to 6.07), use of carbapenems in the previous month (3.35;1.45 to 7.78), biliary prosthesis (2.19;1.24 to 3.90), and moderate or severe chronic kidney disease (1.55;1.07 to 2.26). The AUC of the model was 0.74 [95% CI0.67 to 0.80]. A score was developed, with 7, 6, 5, 4, and 2 points for these variables, respectively, with a negative predictive value of 95% for a score ? 6. A model, including cholangiocarcinoma, biliary prosthesis, hospital acquisition, previous carbapenems, and chronic kidney disease showed moderate prediction ability for enterococcal BT-BSI. Although the score will need to be validated, this information may be useful for deciding empirical therapy in biliary tract infections when bacteremia is suspected. IMPORTANCE Biliary tract infections are frequent, and a significant cause of morbidity and mortality. Bacteremia is common in these infections, particularly in the elderly and patients with cancer. Inappropriate empirical treatment has been associated with increased risk of mortality in bacteremic cholangitis, and the probability of receiving inactive empirical treatment is higher in episodes caused by enterococci. This is because many of the antimicrobial agents recommended in guidelines for biliary tract infections lack activity against these organisms. To the best of our knowledge, this is the first study analyzing the predictive factors for enterococcal BT-BSI and deriving a predictive score

Risk Factors and Predictive Score for Bacteremic Biliary Tract Infections Due to Enterococcus faecalis and Enterococcus faecium: a Multicenter Cohort Study from the PROBAC Project

Biliary-tract bloodstream infections (BT-BSI) caused by Enterococcus faecalis and E. faecium are associated with inappropriate empirical treatment and worse outcomes compared to other etiologies. The objective of this study was to investigate the risk factors for enterococcal BT-BSI. Patients with BT-BSI from the PROBAC cohort, including consecutive patients with BSI in 26 Spanish hospitals between October 2016 and March 2017, were selected; episodes caused by E. faecalis or E. faecium and other causes were compared. Independent predictors for enterococci were identified by logistic regression, and a predictive score was developed. Eight hundred fifty episodes of BT-BSI were included; 73 (8.5%) were due to target Enterococcus spp. (48 [66%] were E. faecium and 25 [34%] E. faecalis). By multivariate analysis, the variables independently associated with Enterococcus spp. were (OR; 95% confidence interval): cholangiocarcinoma (4.48;1.32 to 15.25), hospital acquisition (3.58;2.11 to 6.07), use of carbapenems in the previous month (3.35;1.45 to 7.78), biliary prosthesis (2.19;1.24 to 3.90), and moderate or severe chronic kidney disease (1.55;1.07 to 2.26). The AUC of the model was 0.74 [95% CI0.67 to 0.80]. A score was developed, with 7, 6, 5, 4, and 2 points for these variables, respectively, with a negative predictive value of 95% for a score # 6. A model, including cholangiocarcinoma, biliary prosthesis, hospital acquisition, previous carbapenems, and chronic kidney disease showed moderate prediction ability for enterococcal BT-BSI. Although the score will need to be validated, this information may be useful for deciding empirical therapy in biliary tract infections when bacteremia is suspected. IMPORTANCE Biliary tract infections are frequent, and a significant cause of morbidity and mortality. Bacteremia is common in these infections, particularly in the elderly and patients with cancer. Inappropriate empirical treatment has been associated with increased risk of mortality in bacteremic cholangitis, and the probability of receiving inactive empirical treatment is higher in episodes caused by enterococci. This is because many of the antimicrobial agents recommended in guidelines for biliary tract infections lack activity against these organisms. To the best of our knowledge, this is the first study analyzing the predictive factors for enterococcal BT-BSI and deriving a predictive score.8 página

Sonidos de la América indígena: diseño museográfico y docente de la colección Complutense del Museo de Arqueología y Etnología de América (MAEA, Facultad de Geografía e Historia) referida a la música

Depto. de Historia de América y Medieval y Ciencias HistoriográficasFac. de Geografía e HistoriaFALSEsubmitte

Treatment with tocilizumab or corticosteroids for COVID-19 patients with hyperinflammatory state: a multicentre cohort study (SAM-COVID-19)

Objectives: The objective of this study was to estimate the association between tocilizumab or corticosteroids and the risk of intubation or death in patients with coronavirus disease 19 (COVID-19) with a hyperinflammatory state according to clinical and laboratory parameters. Methods: A cohort study was performed in 60 Spanish hospitals including 778 patients with COVID-19 and clinical and laboratory data indicative of a hyperinflammatory state. Treatment was mainly with tocilizumab, an intermediate-high dose of corticosteroids (IHDC), a pulse dose of corticosteroids (PDC), combination therapy, or no treatment. Primary outcome was intubation or death; follow-up was 21 days. Propensity score-adjusted estimations using Cox regression (logistic regression if needed) were calculated. Propensity scores were used as confounders, matching variables and for the inverse probability of treatment weights (IPTWs). Results: In all, 88, 117, 78 and 151 patients treated with tocilizumab, IHDC, PDC, and combination therapy, respectively, were compared with 344 untreated patients. The primary endpoint occurred in 10 (11.4%), 27 (23.1%), 12 (15.4%), 40 (25.6%) and 69 (21.1%), respectively. The IPTW-based hazard ratios (odds ratio for combination therapy) for the primary endpoint were 0.32 (95%CI 0.22-0.47; p < 0.001) for tocilizumab, 0.82 (0.71-1.30; p 0.82) for IHDC, 0.61 (0.43-0.86; p 0.006) for PDC, and 1.17 (0.86-1.58; p 0.30) for combination therapy. Other applications of the propensity score provided similar results, but were not significant for PDC. Tocilizumab was also associated with lower hazard of death alone in IPTW analysis (0.07; 0.02-0.17; p < 0.001). Conclusions: Tocilizumab might be useful in COVID-19 patients with a hyperinflammatory state and should be prioritized for randomized trials in this situatio

Evaluación de la suplementación de un microencapsulado del jugo de los arilos de granada roja (Punica granatum L) en pacientes con síndrome metabólico.

El síndrome metabólico es definido como un conjunto de alteraciones metabólicas, que incluyen: obesidad central, disminución de las concentraciones de lipoproteínas de alta densidad (c-HDL), aumento en la concentración de triglicéridos, aumento de la presión arterial e hiperglucemia; todos ellos ha sido relacionado en el riesgo de desarrollo de diabetes y enfermedades cardiovasculares, las cuales son importantes causas de mortalidad alrededor del mundo, incluyendo México

Influencia de variables estructurales en la comprensión y recuerdo de textos expositivos

En este trabajo se analizó la interacción entre variables lingüísticas y académicas, en relación a los procesos de comprensión y recuerdo de textos expositivos de Historia, con diferente estructura retórica. Los resultados sugieren que los textos comparativos plantean menos dificultades de comprensión que los que reflejaban procesos causales. La presencia de señalizaciones lingüísticas que clarificaban- la estructura implícita fue una ayuda significativa, especialmente para los estudiantes con bajo rendimiento académico. Por otro lado, respecto al recuerdo, se detectó una interacción entre el nivel académico de los sujetos y la estructura del texto, de modo que cuanto mayor era el nivel académico de los sujetos, mejor se recordaban los textos causales

Influencia de variables estructurales en la comprensión y recuerdo de textos expositivos

En este trabajo se analizó la interacción entre variables lingüísticas y académicas, en relación a los procesos de comprensión y recuerdo de textos expositivos de Historia, con diferente estructura retórica. Los resultados sugieren que los textos comparativos plantean menos dificultades de comprensión que los que reflejaban procesos causales. La presencia de señalizaciones lingüísticas que clarificaban- la estructura implícita fue una ayuda significativa, especialmente para los estudiantes con bajo rendimiento académico. Por otro lado, respecto al recuerdo, se detectó una interacción entre el nivel académico de los sujetos y la estructura del texto, de modo que cuanto mayor era el nivel académico de los sujetos, mejor se recordaban los textos causales