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Search Results: 1 - 10 of 209186 matches for " Arturo Colín-Cruz "
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Atypical Variations of Water Conductivity Prior to Tectonic Earthquakes  [PDF]
Fidel Martínez-García, Arturo Colín-Cruz, Salvador Adame-Martínez, Jorge J. Ramírez-García
International Journal of Geosciences (IJG) , 2015, DOI: 10.4236/ijg.2015.612108
Abstract: Within the framework of precursor events related to earthquakes, this paper analyzes the possible effect on the aquatic environment of the surrounding energy that accompanies earthquakes, particularly in the area where oceanic and continental plates collide (Cocos Plate and North American Plate, south of Mexico). As a preamble, the types of precursor events, characteristics, and their possible origin are described. A project was designed under the assumption that in areas with high frequency and intensity seismicity there is an electrical and electromagnetic potential promoter which is detectable and assessable indirectly by measuring water conductivity behavior, which also may have atypical variations of data; the outcome of intensive conductivity monitoring in different settings, natural as well as manmade (wellsprings, artesian well and a cistern), are presented herein. The results of the conductivity monitoring for seven months, highlight two patterns in data behavior: one pattern shows the subtle dependence of data behavior on the geographic location of data monitoring instruments, revealing that could have a slight relationship between areas with increased seismic frequency and intensity and the presence of atypical conductivity variations. Another pattern reveals the possible relationship between atypical variations in conductivity and subsequent earthquake events; a total of 241 seismic events were analyzed and 59 of them are provided as evidence related with patterns mentioned.
Producción de ácido giberélico a partir de Gibberella fujikuroi utilizando lodo residual municipal como sustrato
Cuali-álvarez,Irene; Pavón-Romero,Sergio H.; Colín-Cruz,Arturo;
Universitas Scientiarum , 2011,
Abstract: objective. to use municipal sewage sludge (lrm) from a wastewater treatment plant located in toluca, state of mexico, to grow the fungus gibberella fujikuroi in submerged fermentation and to produce gibberellic acid (ag3). materials and methods. we used gibberella fujikuroi (cdbb: 268). to obtain ag3, production was verified using as a substrate the standard culture medium (mce). gibberellic acid determination was done with high performance liquid chromatography (hplc) with a varian 9050.9012 equipment. we obtained 6 samples of sludge from a wastewater treatment plant in toluca, state of mexico, that were then characterized. finally, both substrates (lrm and mce) were used in submerged fermentation, and ga3 was obtained by extraction and quantified using hplc. results. the lrm characterization showed that the organic matter content (mo) is of 5.20% (w/v) and the total nitrogen content (nt) is of 0.25% (w/v). such composition is within the range as a substrate for the production of ag3 by gibberella fujikuroi. the fungus was cultivated for 3, 8, 13 and 30 days in sterile sewage sludge with a moisture content of 95.6% (w/v) and in standard culture medium (mce). samples were processed and analyzed by high performance liquid chromatography (hplc). production of ag3 in the lrm was of 460.06 mg/l after 30 days in submerged fermentation at ph 4.0, and of 1,014.46 mg/l in the control. conclusion. the nutrient content of lrm is suitable for the growth of the fungus gibberella fujikuroi and for the production of ga3 when used as a substrate.
Tratamiento de aguas residuales por un sistema piloto de humedales artificiales: evaluación de la remoción de la carga orgánica
Revista internacional de contaminación ambiental , 2009,
Abstract: wastewater treatment is a priority at the global level, because it is important to have enough water of good quality, which will allow an improvement of environment, health and life quality. in mexico, because of insufficient infrastructure, high costs, lack of maintenance and qualified staff, only 36 % of the generated wastewaters are treated, which generates the need for developing alternative technologies for their depuration. artificial wetlands are an alternative due their high efficiency for removal of polluting agents and their low installation and maintenance costs. this paper evaluates the removal percentage of the organic charge of wastewaters in a treatment system of artificial wetlands of horizontal flux, with two vegetal species. the system was designed with three modules installed in a sequential way. at the first one, organisms of the species phragmites australis (cav.) trin. ex steudel were integrated; at the second, organisms of the species typha dominguensis (pers.) steudel, and at the third, both species. the experimental modules were installed at the effluent of a primary treatment, which contains municipal wastewater coming from a research building. the following parameters were analyzed in the water: chemical oxygen demand (cod), ions of nitrogen (no3-, n-no2- y n-nh4+) and total phosphorus. additionally, the total count of bacteria associated to the system was evaluated. results showed that the system is an option for the removal of organic matter and nutrients, of low operation and maintenance costs.
Revista internacional de contaminación ambiental , 2009,
Abstract: El tratamiento de las aguas residuales es una cuestión prioritaria a nivel mundial, ya que es importante disponer de agua de calidad y en cantidad suficiente, lo que permitirá una mejora del ambiente, la salud y la calidad de vida. En México, debido a la insuficiente infraestructura, los altos costos, la falta de mantenimiento y de personal capacitado, sólo 36 % de las aguas residuales generadas reciben tratamiento, lo cual crea la necesidad de desarrollar tecnologías para su depuración. Los humedales artificiales son una alternativa de tratamiento debido a su alta eficiencia de remoción de contaminantes y a su bajo costo de instalación y mantenimiento. En el presente trabajo se evalúa el porcentaje de remoción de la carga orgánica de aguas residuales, en un sistema de tratamiento por humedales artificiales de flujo horizontal y con dos especies vegetales. El sistema fue dise ado con tres módulos instalados de manera secuencial. En el primero se integraron organismos de la especie Phragmites australis (Cav.) Trin. ex Steudel, en el segundo, organismos de la especie Typha dominguensis (Pers.) Steudel y en el tercero las dos especies. Los módulos experimentales fueron instalados a la salida de un tratamiento primario, el cual contiene aguas residuales municipales provenientes de un edificio de investigación. En el agua se analizaron los siguientes parámetros: demanda química de oxígeno (DQO), los iones de nitrógeno (N-NO3-, N-NO2- y N-NH4+) y el fósforo total. También se realizó el conteo de bacterias asociadas al sistema. Los resultados demostraron que el sistema es una opción para la remoción de la carga orgánica y de nutrimentos, de bajo costo de operación y mantenimiento.
Natural Water Conductivity Behavior within the Seismic Pacific Coast of Southern Mexico  [PDF]
Fidel Martínez-García, Arturo Colín-Cruz, Alberto Pereira-Corona, Salvador Adame-Martínez, Jorge J. Ramírez-García
Open Access Library Journal (OALib Journal) , 2016, DOI: 10.4236/oalib.1102836
Abstract: Clouse to faults or unstable areas where an earthquake could happen with capacity of affecting buildings or infrastructure, there is often a previous energy that wanders around surroundings, this energy regularly is associated to electromagnetic emissions that generate an electric potential frequently studied as very, ultra-low and extreme frequency emissions (VLF-ULFELF_ EM) by remote sensing; under the assumption that this natural potential exist, in aquatic environment within the micro-seismic active area in the coastal border of Guerrero and Oaxaca estates, Mexico, an intensive conductivity monitoring in two artesian well was carried out. The results of intensive conductivity (μS/cm) monitoring done since March to July of 2015, using a low-cost Data logger sensor are presented. The results obtained of the study of 235 seismic events show that 61.64% of them manifest prior conductivity oscillation versus 38.36% of early conductivity oscillation; a discussion of the origin of such oscillation and the possible relation with to recharge flux, ground light compression, ground tilt, local electromagnetic energy emissions, human interaction, was debated. The data analysis for long periods of conductivity monitoring and seismic events show that when the number of seismic events became intense, conductivity decreases and vice versa, resulting large fluctuations that grew over time lake waves, within the studied area appears to be there is a possible previous long term energy oscillation associated to the process of earthquakes manifestation around.
Incidence of cancer in children residing in ten jurisdictions of the Mexican Republic: importance of the Cancer registry (a population-based study)
Arturo Fajardo-Gutiérrez, Servando Juárez-Oca?a, Guadalupe González-Miranda, Virginia Palma-Padilla, Rogelio Carreón-Cruz, Manuel Ortega-Alvárez, Juan Mejía-Arangure
BMC Cancer , 2007, DOI: 10.1186/1471-2407-7-68
Abstract: New cases of childhood cancer, which were registered prospectively in nine principal Medical Centers of IMSS during the periods 1998–2000 (five jurisdictions) and 1996–2002 (five jurisdictions), were analyzed. Personnel were specifically trained to register, capture, and encode information. For each of these jurisdictions, the frequency, average annual age-standardized incidence (AAS) and average annual incidence per period by sex and, age, were calculated (rates per 1,000,000 children/years).In total 2,615 new cases of cancer were registered, with the male/female ratio generally >1, but in some tumors there were more cases in females (retinoblastoma, germ cells tumors). The principal groups of neoplasms in seven jurisdictions were leukemias, central nervous system tumors (CNS tumors), and lymphomas, and the combined frequency for these three groups was 62.6 to 77.2%. Most frequently found (five jurisdictions) was the North American-European pattern (leukemias-CNS tumors-lymphomas). Eight jurisdictions had AAS within the range reported in the world literature. The highest incidence was found for children underless than five year of age. In eight jurisdictions, leukemia had high incidence (>50). The AAS of lymphomas was between 1.9 to 28.6. Chiapas and Guerrero had the highest AAS of CNS tumors (31.9 and 30.3, respectively). The frequency and incidence of neuroblastoma was low. Chiapas had the highest incidence of retinoblastoma (21.8). Germ-cell tumors had high incidence.The North American-European pattern of cancers was the principal one found; the overall incidence was within the range reported worldwide. In general but particularly in two jurisdictions (Yucatán and Chiapas), it will be necessary to carry out studies concerning the causes of cancer in children. Due to the little that is known about the incidence of cancer in Mexican children, it will be necessary to develop a national program to establish a cancer registry for the whole of the country.Cancer in ch
Corrosion Behavior of Titanium and Nickel-based Alloys in HCl and HCl + H2S Environments
J. Mendoza-Canales and J. Marín-Cruz
International Journal of Electrochemical Science , 2008,
Abstract: Titanium grade 2 (UNS R50400), alloy 400 (UNS N04400), alloy 20 (UNS N08020) and alloy C-276 (UNS N10276) were electrochemically explored to determine their corrosion susceptibility behavior when exposed to environments typically found on existent atmospheric column overhead systems in mexican crude oil refineries. Linear anodic polarization was used to attain electrochemical results. Main corrosive species –present in actual overhead systems for a characteristic heavy crude oil produced in Mexico- were reproduced by performing experiments in two distinct electrolytes (0.05 mol/L HCl and 0.05 mol/L HCl + 500 ppm H2S in aqueous solution) at 40 °C. Metals were examined at pH 1.5, 4, 6, 8 and 10 values for both electrolytes to identify effects of key contaminants. Results revealed that each explored metal exhibits particular corrosion susceptibility depending on pH of environment, suggesting that corrosion susceptibility of every metal is a function of particular metal-environment conditions.
Intrinsic Motives of Autonomy, Self-Efficacy, and Satisfaction Associated with Two Instances of Sustainable Behavior: Frugality and Equity  [PDF]
Víctor Corral-Verdugo, Daniel González-Lomelí, Marisol Rascón-Cruz, Víctor O. Corral-Frías
Psychology (PSYCH) , 2016, DOI: 10.4236/psych.2016.75068

This paper explores the relationship between sustainable behavior, indicated by frugal and equitable actions, and three intrinsic motives: satisfaction, autonomy and self-efficacy. One-hundred and seventy-three undergraduates at a Mexican university responded to a questionnaire investigating their sustainable actions and the intrinsic repercussions derived from those actions. Using structural equations, a model is specified and tested, which reveals the presence of a higher-order factor (sustainable behavior) subjacent to a high and significant covariance between frugal and equitable behaviors. The resulting higher-order-factor, in turn, significantly predicts the report of feelings of satisfaction, autonomy, and self-efficacy. These findings are in line with the idea that sustainable behavior is to a good extent self-determined through the operation of intrinsic consequences, which instigate people’s pro-social and pro-environmental actions.

Epidemiological and some clinical characteristics of neuroblastoma in Mexican children (1996–2005)
Servando Juárez-Oca?a, Virginia Palma-Padilla, Guadalupe González-Miranda, Alicia Siordia-Reyes, Enrique López-Aguilar, Martha Aguilar-Martínez, Juan Mejía-Aranguré, Rogelio Carreón-Cruz, Mario Rendón-Macías, Arturo Fajardo-Gutiérrez
BMC Cancer , 2009, DOI: 10.1186/1471-2407-9-266
Abstract: A population-based, prolective study, with data obtained from the Childhood Cancer Registry of the Instituto Mexicano de Seguro Social. Statistical analysis: The simple frequencies of the variables of the study and the annual average incidence (per 1,000,000 children/years) by age and sex were obtained. The trend was evaluated by calculating the annual percentage of change. The curves of Kaplan-Meyer were employed for the survival rate and the log-rank test was used to compare the curves.Of a total of 2,758 children with cancer registered during the period from 1996–2005, 72 (2.6%) were identified as having Group IV, defined according to the International Classification of Childhood Cancer. The incidence for NB was 3.8 per 1,000,000 children/year; NB was highest in the group of children under one year of age, followed by the group of children between the ages 1–4 years (18.5 and 5.4 per 1,000,000 children/years, respectively). The male/female ratio was 1.1 and there was no trend toward an increase. The time of diagnosis was 26 days (median), but varied according to the stage at diagnosis. Stages III and IV were presented in 88% of the cases. There was no association between the stage, the age at time of diagnosis, or the histological pattern. The overall five-year survival rate was 64%; the patients with stage I, II, III, or IVs did not die; and the five-year survival rate of cases in Stage IV was 40%.It is possible that the low incidence of neuroblastoma in Mexican children is due to the difficulty in diagnosing the cases with the best prognosis, some of which could have had spontaneous regression. There was no trend to an increase; the majority of the cases were diagnosed in the advanced stages; and the overall five-years survival rate was similar to that for developed countries.During fetal life, cells of the neural crest colonize the sympathetic ganglions, the medulla of adrenal glands, and other sites. Neuroblastoma (NB) and related tumors [ganglioneuroblastoma
Exploración y caracterización morfológica de poblaciones de la jamaica (Hibiscus sabdariffa L.) del estado de Guerrero, México Morphological exploration and characterization of roselle (Hibiscus sabdariffa L.) populations from state of Guerrero, Mexico
Noé Alarcón-Cruz,Rafael Ariza Flores,Aristeo Barrios Ayala,David H. Noriega Cantú
Revista mexicana de ciencias agrícolas , 2012,
Abstract: El presente estudio se realizó en las instalaciones de la Universidad Autónoma Chapingo durante el periodo de 2007 a 2009 y tuvo como objetivo caracterizar morfológicamente a 47 colectas de jamaica (Hibiscus sabdariffa L.) que representaron a poblaciones del estado de Guerrero. En la caracterización morfológica se evaluaron 50 variables, mismas que se separaron en 40 cuantitativas y 10 cualitativas. De las cuantitativas se seleccionaron 25 variables y de las cualitativas cinco con alta significancia. En la caracterización de datos morfológicos se utilizaron correlaciones, análisis de correspondencia y de agrupamiento. Los caracteres morfológicos cuantitativos que más aportaron a la diferenciación de los genotipos de jamaica fueron: longitud en la base del lóbulo principal de la hoja, longitud promedio del fruto, perímetro promedio del fruto, longitud vertical de la hoja, ángulo del lóbulo izquierdo de la hoja, croma (C) de la flor y promedio de color de hoja cuantificado con colorímetro (L). Los caracteres cualitativos que mejor ayudaron a definir los grupos de jamaicas fueron el color visual de la hoja, precocidad, color aparente del tallo, color de brácteas y ausencia o presencia de glándulas melíferas que contribuyeron de manera substancial en la separación de los grupos. During 2007 to 2009 period this study was performed. Taking place at facilities of Universidad Autonoma Chapingo, the aim was to morphologically characterize 47 collections of roselle (Hibiscus sabdariffa L.) that represented populations from the state of Guerrero. In morphological characterization 50 variables were assessed, which were divided into 40 quantitative and 10 qualitative variables. 25 were selected from the quantitative ones and five with high importance from the qualitative. For morphological data characterization correlations, correspondence and grouping analysis were used. The quantitative morphological characters that most contributed to differentiation of roselle genotypes were: width at the base of leaf's main lobule, average length of fruit, average fruit perimeter, leaf's vertical length, leaf's left lobule angle, flower's chroma (C) and average leaf's color quantified by colorimeter (L). The qualitative characters that best helped to define roselle groups were leaf's visual color, earliness, stem's apparent color, bracts color and lack or presence of glands, which substantially contributed to segregate the groups.
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