23 research outputs found
Plan de manejo de residuos de construcción y demolición. Caso de estudio: Planta de asfalto de Loja-Ecuador.
The construction sector is important for the development of a territory; however, it has a significant impact on the environment, producing interesting amounts of waste, and in Ecuador, this situation is no exception. Therefore, it is crucial that companies and professionals in the sector adopt sustainable practices, such as the recycling of construction and demolition waste (RCD) as a responsible alternative that conserves natural resources and reduces the amount of waste sent to landfills. Based on a qualitative research, this article analyzed the importance of reusing RCD as the main component to produce new concrete and asphalt. Through an international bibliographic review and the use of competent regulations in force in Ecuador, a RCD management plan for the asphalt plant in the Loja canton is presented as a result. This document shows a complete management of RCD, from planning, through collection and transfer, minimization, segregation and storage, waste reprocessing, re-direction, monitoring and control. From the results obtained, it is shown that RCD can be used, as an example; reused asphalt can be included in a new pavement up to 40%.El sector de la construcción es importante para el desarrollo de un territorio, sin embargo, tiene un impacto significativo en el medio ambiente produciendo cantidades interesantes de desechos y en Ecuador dicha situación no es ajena. Por lo tanto, es crucial que las empresas y profesionales del sector adopten prácticas sostenibles; como el reciclaje de residuos de construcción y demolición (RCD) configurándose como una alternativa responsable que permite conservar recursos naturales y disminuir la cantidad de desechos enviados a vertederos. En base a una investigación de tipo cualitativa este artículo analizó la importancia del reaprovechamiento de RCD como componente principal para producir nuevos concretos y asfaltos. Mediante revisión bibliográfica internacional y el uso de normativas vigentes competentes en Ecuador se presenta como resultado el plan de manejo de RCD para la planta asfáltica del cantón Loja. Este documento exhibe una gestión completa de RCD, que va desde planificación, pasando por la recolección y traslado, la minimización, la segregación y almacenamiento, el reprocesamiento de desechos, el re-direccionamiento, hasta el seguimiento y control. A partir de los resultados obtenidos, se demuestra que los RCD, pueden ser aprovechados. Como ejemplo: el asfalto reutilizado puede incluirse en un nuevo pavimento hasta en un 40%
Factores condicionantes y climáticos en la amenaza de incendio forestal de la microcuenca del Río Chazo Juan, Ecuador
This paper evaluates the incidence of conditioning factors (land use and vegetation cover, geomorphology and slope) and climatic factors (temperature, wind speed and relative humidity) on the hazard of forest fires in the Chazo Juan river micro-watershed in Bolivar province, which is part of the Guayas river basin of great importance for Ecuador. It was used, for the conditioning variables, information from the cartographic base scale 1:25,000 of the Ministry of Agriculture, Livestock, Aquaculture and Fisheries; for a more detailed description of the climatic variables, it was used information from the yearbooks of nearby meteorological stations of the National Institute of Meteorology and Hydrology and three meteorological stations that were installed in the study area. The Delphi method was used to weight the variables of the conditioning and climatic factors, which were interpolated and correlated using map algebra in the ArcGis software (10.3) to obtain the Weighted Forest Fire Threat Index and prepare maps with hazard levels for scenarios (maximum, average and minimum values) at a local scale; the correlation of variables was done using the Pearson method. The results show that the conditioning variables have a significant incidence (very high and high); while the climatic variables have little incidence (medium, low, very low and even null in the wind speed in scenarios of maximum and minimum values); there is an inverse relationship between temperature and relative humidity, the higher the temperature the lower the humidity or vice versa, this influences the increase or decrease of the hazard levels.El trabajo evalúa la incidencia de los factores condicionantes (uso de suelo y cobertura vegetal, geomorfología y pendiente) y climáticos (temperatura, velocidad del viento y humedad relativa) en la amenaza de incendios forestales de la microcuenca del río Chazo Juan en la provincia Bolívar, que forma parte de la cuenca del río Guayas de gran importancia para Ecuador. Para las variables condicionantes se utilizó información de base cartográfica escala 1:25.000 del Ministerio de Agricultura Ganadería, Acuacultura y Pesca; para un mayor detalle de las variables climáticas se empleó información de anuarios de estaciones meteorológicas cercanas del Instituto Nacional de Meteorología e Hidrología y se instalaron tres estaciones meteorológicas en la zona de estudio. A través del método Delfhi se ponderó las variables de los factores condicionantes y climáticos que fueron interpolados y correlacionados mediante el algebra de mapas en el software ArcGis (10.3) para obtener el Índice Ponderado de Amenaza de Incendio Forestal y elaborar mapas con niveles de amenaza para escenarios (valores máximos, promedios y mínimos) a escala local, la correlación de variables se realizó mediante el método Pearson. Los resultados muestran que, las variables condicionantes presentan una incidencia significativa (muy alta y alta); mientras que las variables climáticas poca incidencia (medio, bajos, muy bajos e incluso nula en la velocidad del viento en escenarios de valores máximos y mínimos); existe una relación inversa, entre la temperatura y humedad relativa, a mayor temperatura menor humedad o viceversa, esto influye en el incremento o disminución de los niveles de amenaza
Physical vulnerability and exposure to the threat of mass movements of the Culebrillas Drinking Water Systems of the City of Cuenca
Introducción: En la ciudad de Cuenca-Ecuador existen varios sistemas de abastecimiento de agua potable, algunos de los cuales se encuentran en zonas de expansión urbana y expuestos a amenazas. Objeto: Analizar la vulnerabilidad física y exposición ante la amenaza de movimientos en masa del sistema de agua potable Culebrillas, que se encuentra en la zona de expansión urbana y cubre una parte de la ciudad. Metodología: Se aplicó una metodología cualitativa y se utilizó una ficha de entrevista a técnicos de la Empresa Pública de Telecomunicaciones, Agua Potable y Alcantarillado para recolectar información de cada uno de los indicadores de vulnerabilidad de los componentes del sistema, que fueron ponderados para obtener un índice de vulnerabilidad física, el mismo que permitió determinar el nivel de vulnerabilidad, cuyos criterios para la ponderación se aplicó el método Delphi; mientras que, para establecer la exposición ante la amenaza de movimientos en masa de la infraestructura, se utilizó el mapa de movimiento en masa elaborado por el Ministerio de Agricultura, Ganadería, Acuacultura y Pesca y Secretaría Técnica de Gestión de Riesgos. Resultados: Los resultados indican que el sistema de agua potable Culebrillas en sus componentes: captación, posee un índice de 20 puntos que representa el nivel de vulnerabilidad bajo; conducción, con 25 puntos equivale a bajo; planta de tratamiento con 19,3 puntos representa bajo; distribución, que a su vez está compuesta por los tanques de reservas de distribución con 25,2 puntos que corresponde a bajo y la red de distribución con 48,4 puntos que representa medio; con respecto a la exposición a la amenaza movimiento en masa: la infraestructura de la captación-tanque, en su mayor parte la red de conducción, con menor número de tanques y la red de distribución se encuentran en zonas de nivel alto. Conclusión: El presente estudio constituye en un modelo piloto para evaluar los otros sistemas que abastece a la ciudad de Cuenca, así como, se podría replicar en otros centros poblados del país.Introduction: In the city of Cuenca-Ecuador there are several drinking water supply systems, some of which are located in urban expansion areas and exposed to threats. Object: To analyze the physical vulnerability and exposure to the threat of mass movements of the Culebrillas drinking water system, which is located in the urban expansion zone and covers a part of the city. Methodology: A qualitative methodology was applied and an interview form was used with technicians from the Public Telecommunications Company, Drinking Water and Sewerage Company to collect information on each of the vulnerability indicators of the components of the system, which were weighted to obtain a physical vulnerability index, which allowed determining the level of vulnerability, the criteria for weighting the Delphi method was applied Aquaculture and Fisheries and Technical Secretariat for Risk Management. Results: The results indicate that the Culebrillas drinking water system in its components: catchment, has an index of 20 points representing the level of low vulnerability; driving, with 25 points equals low; treatment plant with 19,3 points represent low; distribution, which in turn is composed of the distribution reserve tanks with 25,2 points corresponding to low, and the distribution network with 48,8 points Driving, with fewer tanks and distribution network are in high level areas. Conclusion: This study constitutes a pilot model to evaluate the other systems that supplies the city of Cuenca, as well as, it could be replicated in other populated centers of the country
Relationship Between Dyslipidemia and Obesity in Children
Purpose: Dyslipidemia is a general term that refers to abnormal levels of lipids. The purpose of this research was to determine the relationship among the nutritional state and the percentage of body fat with the levels of lipids in 10 to 13 year old children living in the city of Durango, Mexico. Method: The study was carried out with 823 elementary school children. The selection was done at random. The biochemical studies were done in a subpopulation of 425 children. Each child underwent the following studies: sociodemographic, anthropometric and corporal composition. After fasting overnight, a venous blood sample was obtained. lipid profile including cholesterol, LDL-C, HDL-C and triglycerides were determined in serum. In order to classify lipid levels we used the reference values suggested by the National Cholesterol Education Program (NCEP). The desirable values were: TC \u3c170 mg\u3e/dl, HDL -C \u3e45 mg/dl, LDL -C \u3c110 mg\u3e/dl and TG \u3c100 mg\u3e/dl. The nutritional state was calculated according the age and sex specific BMI values developed by the CDC. Fat mass content was determined using a bioelectrical impedance analyzer (Tanita TBF-215). Statistical analyses were performed using SPSS14. Results: This study included 428 (52%) boys and 395 (48%) girls. Mean age was 11.5 years. The prevalence of overweight and obesity was 36.7. In the population studied we found abnormal levels of lipids in: cholesterol (41.8%), HDL-C (55.8%), LDL-C (32.3%) and TG (38.5%). The girls showed lower levels of HDL-C than the boys (p \u3c 0.05), the other lipoproteins were not statistical different ( p \u3e 0.05). The lipids levels (TC, LDL-C and TG) were higher in those with a BMI greater than 85 th percentile of BMI, and DHL-C was lower. In those with a body fat greater than 20%, all the lipids levels resulted abnormal. Conclusions: A high risk of dislypidemia was associated with gender, BMI and body fat
Leptin and its Association with Obesity among Mexican Adolescents
Purpose: To investigate the association between leptin concentrations and nutritional status among a Mexican adolescent population. Methods: Cross-sectional study with 448 adolescents attending five schools in Durango, Mexico. Serum leptin concentrations were measured by ELISA. Other measurements included height, weight, and waist and hip circumference. Body fat of participants was assessed with bio-electrical impedance using a body composition analyzer InBody-720. Sociodemographic information was also collected. Results: Based on IOTF BMI cut-off points, 34.1% of adolescents were overweight and obese and prevalence rates were higher among females (37.1%) than males (29.5%). In agreement with waist circumference, 22.5% of participants were overweight and had abdominal obesity; and based on waist-to-hip ratio 35.5% had truncal obesity. Leptin concentration levels among females (19.33 ng/dL) were two times higher than among males (40.07 ng/dL) with a statistical significant difference (p=0.000). Leptin levels among obese females (69.92 ng/dL) were three times higher than among underweight females (17.70 ng/dL). Conversely, leptin levels among males (43.52 ng/dL) were four times higher than among their underweight counterparts (10.08 ng/dL). Mean leptin levels among women with body fat greater than 28% (46.44 ng/dL) were statistically different and 1.7 times higher than those with lower body fat (25.96 ng/dL) (p=0.000). Mean leptin levels among males with body fat greater than 20% (30.17 ng/dL) were statistically different (p=0.000) and 2.4 times higher than among males with lower body fat (12.35 ng/dL). Among both females and males, leptin concentration levels were positively and significantly associated with visceral body fat (R2=0.344 females; R2=0.373 males; p=0.000). Conclusions: Significant correlations between leptin and BMI, body fat percentage, and visceral adipose tissue area indicate that this hormone can be used as a biomarker for obesity among adolescents
Insulin Resistance and Obesity in Mexican Youth
Purpose: Although research shows that prevalence rates of insulin resistance (IR) is increasing in children, little is known about the impact of obesity in IR in Mexican youth. This study investigated the association between overweight, obesity, and insulin resistance in Mexican adolescents. Methods: Data were collected from 448 adolescents aged 12 to 18 years from a random sample of a high school student population in Durango, Mexico. After fasting overnight, blood samples were obtained from participants. Glucose, insulin, lipid profile, leptin, insulin growth factor, growth hormone, cortisol, TNF-alpha, and C-reactive protein were determined in serum. Body Mass Index (BMI) was calculated using CDC parameters. Fat mass was determined using a bioelectrical impedance analyzer. THE HOMA index was used to calculate IR and a Keskin diagnosis value of 3.1 was considered. Statistical analyses were conducted.
Results: The mean age of the sample was 15.44 years and a majority was female (61.4%). Prevalence of overweight and obesity was 31.9%. The BMI mean was slightly higher in females (65.5) than in males (61.1) (p \u3e0.05). Females had a greater mean of body fat percentage (31.9) than males (20.2) (p\u3c 0.05). Prevalence of resistance to insulin by HOMA-IR was 14.4% with no statistically significant gender differences. The IR mean was higher in adolescents with greater BMI (≥85th percentile) than those with low and normal BMI (\u3c85th percentile) (p \u3c0.05). Adolescents with high IR levels (≥3.1) had higher mean values of corporal fat (37.69%) and BMI (89.76) than those with lower IR levels (\u3c3.1) and lower corporal fat and BMI values (26.4%3 and 61.67, respectively). Conclusions: The significant association found between obesity and insulin resistance in Mexican adolescents suggests a greater risk for the development of degenerative disease in this young population during adulthood. Public health programs among Mexican adolescents are essential to prevent obesity and IR related consequences
Relationship Between Leptin and Obesity in Mexican Chidren
Purpose: The expression and secretion of the leptin are thoroughly related with the regulation of food intake, energy balance and body fat. Obesity is defined as excess of body fat. The purpose of this research was to determine the relationship among the nutritional state and the percentage of body fat with the levels of leptin in 10 to 13 year old children living in the city of Durango, Mexico. Method: The study was carried out with 823 elementary school children. The selection was done at random. The biochemical studies were done in a subpopulation of 425 children. Each child underwent the following studies: sociodemographic, anthropometric and corporal composition. After fasting overnight, a venous blood sample was obtained. Leptin, glucose, lipid profile, insulin, Insulin growth factor, growth hormone, cortisol, TNF-alpha and C-reactive protein were determined in serum. The nutritional state was calculated according the age and sex specific BMI values developed by the CDC. Fat mass content was determined using a bioelectrical impedance analyzer (Tanita TBF-215). Statistical analyses were performed using SPSS14. Results: The studied population included 428 (52%) boys and 395 (48%) girls. Mean age was 11.50 years. The prevalence of overweight including obesity (≥85th percentile of the IMC) was 36.7%. The mean of the percentage of corporal fat in the women was 27.04 and in the males 22.05 (p \u3c0.05). The mean of the concentration of leptin in the women was 27.84 ng/mL and in the males 17.62 (p \u3c0.05). In the female group the leptin level increased with the age. The mean of leptin concentration in the group with ≥95th percentile of the IMC was higher (47.07 ng/mL) than those with 5-84.99th percentile of the IMC (14.01 ng/mL) (p \u3c0.05). The mean of leptin concentration in the group with \u3c20% body fat was lower (8.92 ng/mL) than the group with ≥40% body fat (59.94 ng/mL) (p \u3c0.05). Conclusions: The leptin level was associated with gender, body mass index (IMC) and body fat
Flujo sanguíneo y el oxido nitríco son factores que ejercen efectos sobre la hipertensión.
Se efectuó una revisión de la literatura sobre la epidemiología de la hipertensión. Considerando necesario rescatar los conceptos básicos sobre la hipertensión y su epidemiología para entender mejor su relevancia y el desarrollo de la hipertensión.
En este sentido, se analizaron algunas variables que podrían estar involucradas en el desarrollo de la HTA. En este contexto, se ha observado que el flujo sanguíneo modula el tono vascular, que es traducido por cambios en la presión de perfusión y la resistencia vascular, siendo dependiente del endotelio vascular y que actúa mediante dos fuerzas hemodinámicas; 1) una fuerza de fricción (shear-stress) que actúa en la interfase entre la sangre que fluye y las células endoteliales y 2) una fuerza de presión sobre los vasos sanguíneos que induce un estiramiento circunferencial del tejido. Se ha postulado que el endotelio es capaz de detectar cambios producidos por el flujo coronario y en consecuencia tiene la capacidad de responder a esos cambios liberando sustancias vasoactivas como es el caso del oxido nítrico. En conclusión todos estos cambios ejercen un efecto sobre el tono vascular. Es así, que la alteración de esos cambios puede jugar un papel muy importante en el desarrollo de la hipertensión