Radiación fractal en la ecuación de Boussinesq del drenaje agrícola

MANUEL ZAVALA TREJO CARLOS FUENTES RUIZ HEBER ELEAZAR SAUCEDO ROJAS (2004, [Artículo])

Se aborda el estudio de las condiciones que deben sujetar a la ecuación de Boussinesq en la frontera de los drenes agrícolas. Proponiendo que la transferencia de agua del suelo hacia el interior de estos se describa con una condición de frontera tipo radiación, la cual permite describir las evoluciones de la carga hidráulica y del gasto de drenaje, considerando explícitamente la variación de la resistencia al flujo del agua en la interfaz suelo-dren. A partir del análisis de los modelos extremos de la conductividad hidráulica de Purcell (1949) y de Childs y Collis-George (1950) así como de la aplicación de conceptos de geometría fractal, se establece que la resistencia en la interfaz suelo-dren es inversamente proporcional a una potencia fractal de la carga hidráulica sobre el dren con el exponente definido implícitamente, en función de las porosidades totales del suelo y de la pared del dren. La capacidad de descripción de la condición de radiación fractal se verifica comparando los resultados que se obtienen al aplicar esta relación con datos de un experimento de drenaje realizado en laboratorio. El buen acuerdo entre los resultados teóricos y los datos experimentales permite recomendar el uso de la condición de radiación fractal para describir el flujo de agua del suelo hacia los drenes agrícolas durante la recesión de la superficie libre.

Drenaje agrícola Interfaz suelo-dren Resistencia al flujo de agua Conductividad hidráulica CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA

Responsabilidad social empresarial de las empresas mineras en Sonora: Grupos de interés, prácticas y avances en el siglo XXI

ERNESTINA ARVIZU ARMENTA (2020, [Tesis de doctorado])

La importancia que el sector minero representa en el desarrollo económico en México no es reciente. No obstante, a través de los años el sector ha adquirido fuerza, consolidándose como una de las principales actividades económicas del país. De forma particular, en el estado de Sonora, México, el sector ha crecido y ha adquirido notoriedad reflejada en indicadores como la generación de empleos, la generación de cadenas de valor, la creación de infraestructura y la inversión extranjera por mencionar algunos.

El crecimiento y la consolidación que el sector minero experimenta actualmente ha generado también un interés social por conocer y evaluar cómo se llevan a cabo las decisiones que involucran aquellas prácticas y procesos bajo los cuales operan las empresas del sector minero.

Es mediante la información que la empresa proporciona a sus principales grupos de interés que éstos identifican si las empresas mineras establecidas siguen un enfoque de responsabilidad social empresarial dirigido a cumplir con sus principales demandas y necesidades en las dimensiones económicas, sociales y ambientales.

Los resultados de esta investigación muestran que la Responsabilidad Social Empresarial ejercida por las empresas mineras estudiadas todavía está enfocada en cumplir de manera primordial con los intereses de la empresa, aunque el enfoque no ha logrado convencer a los grupos de interés acerca de los beneficios que puede obtener de esta actividad. Desde esta perspectiva se concluye que el enfoque de RSE ejercido por las empresas mineras estudiadas se encuentra en una etapa emergente y experimental, la cual se puede observar sobre todo en los modelos de desarrollo comunitario promovidos por las empresas mineras.

CIENCIAS SOCIALES Industria minera Responsabilidad social de la empresa Sonora

From character to person. A contribution to the study of characterization of real people in factual narrative texts   

Martín Ignacio Koval (2023, [Artículo, Artículo])

In this paper we propose some arguments in favor of the terminological differentiation between agents in fictional settings (characters) and those in factual settings (people, actors, etc.), and nevertheless we suggest the applicability of the tools of narratology to factual journalistic texts. Then, we propose an analytical-descriptive model -conceived only as provisional- which, although it resorts to traditional tools of narratology "in the strict sense" (that is, the one that deals exclusively with fictional texts), tries to do justice to the aforementioned categorical difference between fictional and factual texts insofar as it is accompanied, in the presentation, by a series of mediations that allow the extrapolation from one setting to the other. This model will be explained on the basis of the analysis of a fragment of a recently published journalistic chronicle, referring to the death of the Argentine soccer player Diego Maradona.

factualidad personaje persona caracterización reacción afectiva HUMANIDADES Y CIENCIAS DE LA CONDUCTA HUMANIDADES Y CIENCIAS DE LA CONDUCTA Factuality character person characterization affective reaction

Functional characterization and cellular dynamics of the CDC-42 - RAC - CDC-24 module in neurospora crassa

CYNTHIA LIZZETH ARAUJO PALOMARES (2011, [Artículo])

Rho-type GTPases are key regulators that control eukaryotic cell polarity, but their role in fungal morphogenesis is only beginning to emerge. In this study, we investigate the role of the CDC-42 - RAC - CDC-24 module in Neurospora crassa. rac and cdc-42 deletion mutants are viable, but generate highly compact colonies with severe morphological defects. Double mutants carrying conditional and loss of function alleles of rac and cdc-42 are lethal, indicating that both GTPases share at least one common essential function. The defects of the GTPase mutants are phenocopied by deletion and conditional alleles of the guanine exchange factor (GEF) cdc-24, and in vitro GDP-GTP exchange assays identify CDC-24 as specific GEF for both CDC-42 and RAC. In vivo confocal microscopy shows that this module is organized as membrane-associated cap that covers the hyphal apex. However, the specific localization patterns of the three proteins are distinct, indicating different functions of RAC and CDC-42 within the hyphal tip. CDC-42 localized as confined apical membrane-associated crescent, while RAC labeled a membrane-associated ring excluding the region labeled by CDC42. The GEF CDC-24 occupied a strategic position, localizing as broad apical membrane-associated crescent and in the apical cytosol excluding the Spitzenkörper. RAC and CDC-42 also display distinct localization patterns during branch initiation and germ tube formation, with CDC-42 accumulating at the plasma membrane before RAC. Together with the distinct cellular defects of rac and cdc-42 mutants, these localizations suggest that CDC-42 is more important for polarity establishment, while the primary function of RAC may be maintaining polarity. In summary, this study identifies CDC-24 as essential regulator for RAC and CDC-42 that have common and distinct functions during polarity establishment and maintenance of cell polarity in N. crassa. © 2011 Araujo-Palomares et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

CDC24 protein, guanine nucleotide exchange factor, protein Cdc42, Rac protein, unclassified drug, cell cycle protein, fungal protein, membrane protein, multiprotein complex, protein Cdc42, Rac protein, allele, apical membrane, article, assay, cell me BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA MICROBIOLOGÍA MICROBIOLOGÍA

A simple extension to the CMASA method for the prediction of catalytic residues in the presence of single point mutations

David Israel Flores Granados (2014, [Artículo])

The automatic identification of catalytic residues still remains an important challenge in structural bioinformatics. Sequence-based methods are good alternatives when the query shares a high percentage of identity with a well-annotated enzyme. However, when the homology is not apparent, which occurs with many structures from the structural genome initiative, structural information should be exploited. A local structural comparison is preferred to a global structural comparison when predicting functional residues. CMASA is a recently proposed method for predicting catalytic residues based on a local structure comparison. The method achieves high accuracy and a high value for the Matthews correlation coefficient. However, point substitutions or a lack of relevant data strongly affect the performance of the method. In the present study, we propose a simple extension to the CMASA method to overcome this difficulty. Extensive computational experiments are shown as proof of concept instances, as well as for a few real cases. The results show that the extension performs well when the catalytic site contains mutated residues or when some residues are missing. The proposed modification could correctly predict the catalytic residues of a mutant thymidylate synthase, 1EVF. It also successfully predicted the catalytic residues for 3HRC despite the lack of information for a relevant side chain atom in the PDB file. © 2014 Flores et al.

1UU9 protein, 3HRC protein, protein, thymidylate synthase, unclassified drug, protein kinase, thymidylate synthase, accuracy, algorithm, Article, CMASA, CMASA Substitution Matrix, Contact Matrix Average Deviation, controlled study, correlation coeffi CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA MATEMÁTICAS ANÁLISIS NUMÉRICO ANÁLISIS NUMÉRICO

Comparative live-cell imaging analyses of SPA-2, BUD-6 and BNI-1 in Neurospora crassa reveal novel features of the filamentous fungal polarisome

Alexander Lichius (2012, [Artículo])

A key multiprotein complex involved in regulating the actin cytoskeleton and secretory machinery required for polarized growth in fungi, is the polarisome. Recognized core constituents in budding yeast are the proteins Spa2, Pea2, Aip3/Bud6, and the key effector Bni1. Multicellular fungi display a more complex polarized morphogenesis than yeasts, suggesting that the filamentous fungal polarisome might fulfill additional functions. In this study, we compared the subcellular organization and dynamics of the putative polarisome components BUD-6 and BNI-1 with those of the bona fide polarisome marker SPA-2 at various developmental stages of Neurospora crassa. All three proteins exhibited a yeast-like polarisome configuration during polarized germ tube growth, cell fusion, septal pore plugging and tip repolarization. However, the localization patterns of all three proteins showed spatiotemporally distinct characteristics during the establishment of new polar axes, septum formation and cytokinesis, and maintained hyphal tip growth. Most notably, in vegetative hyphal tips BUD-6 accumulated as a subapical cloud excluded from the Spitzenkörper (Spk), whereas BNI-1 and SPA-2 partially colocalized with the Spk and the tip apex. Novel roles during septal plugging and cytokinesis, connected to the reinitiation of tip growth upon physical injury and conidial maturation, were identified for BUD-6 and BNI-1, respectively. Phenotypic analyses of gene deletion mutants revealed additional functions for BUD-6 and BNI-1 in cell fusion regulation, and the maintenance of Spk integrity. Considered together, our findings reveal novel polarisome-independent functions of BUD-6 and BNI-1 in Neurospora, but also suggest that all three proteins cooperate at plugged septal pores, and their complex arrangement within the apical dome of mature hypha might represent a novel aspect of filamentous fungal polarisome architecture. © 2012 Lichius et al.

fungal protein, protein BNI 1, protein BUD 6, protein SPA 2, protein Spk, unclassified drug, actin binding protein, cytoskeleton protein, fungal protein, article, cell fusion, cellular distribution, comparative study, conidium, controlled study, cyto BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA MICROBIOLOGÍA MICROBIOLOGÍA

Vital and viable services for natural resources management in Latin America

EDUARDO LOPEZ RAMIREZ JOSE LUIS MARTINEZ RUIZ Ricardo Víctor López Mera (2013, [Documento de trabajo])

VIVACE se basa en la innovación técnica de los servicios vitales y viables, especialmente los de abasto de agua potable, saneamiento y manejo de residuos sólidos en áreas periurbanas, con la idea de integrar analíticamente los enfoques y herramientas para el soporte de decisiones. Se desarrolla mediante estudios de casos realizados en México y Argentina. El trabajo que compete al IMTA es un estudio en la zona periurbana de Xochimilco, en la Ciudad de México.

Abastecimiento de agua Tratamiento de aguas residuales Tecnología apropiada Informes de proyectos CIENCIAS SOCIALES

Research for development approaches in mixed crop-livestock systems of the Ethiopian highlands

Million Gebreyes James Hammond Lulseged Tamene Getachew Agegnehu Rabe Yahaya Anthony Whitbread (2023, [Artículo])

This study presents processes and success stories that emerged from Africa RISING's Research for Development project in the Ethiopian Highlands. The project has tested a combination of participatory tools at multiple levels, with systems thinking and concern for sustainable and diversified livelihoods. Bottom-up approaches guided the selection of technological interventions that could address the priority farming system challenges of the communities, leading to higher uptake levels and increased impact. Joint learning, appropriate technology selection, and the creation of an enabling environment such as the formation of farmer research groups, the establishment of innovation platforms, and capacity development for institutional and technical innovations were key to this study. The study concludes by identifying key lessons that focus more on matching innovations to community needs and geographies, systems orientation/integration of innovations, stepwise approaches to enhance the adoption of innovations, documenting farmers' capacity to modify innovations, building successful partnerships, and facilitating wider scaling of innovations for future implementation of agricultural research for development projects.

Action Research Systems Thinking CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA INNOVATION PARTNERSHIPS SCALING UP INTEGRATED CROP-LIVESTOCK SYSTEMS

Synthesis of minerals with iron oxide and hydroxide contents as a sorption medium to remove arsenic from human consumption

Sofía Garrido Hoyos LOURDES ROMERO VELAZQUEZ (2016, [Artículo])

Arsenic has been classified as a toxic and carcinogenic chemical element. It therefore presents a serious environmental problem in different regions of the country and the world. In the present work, two adsorbent media were developed and evaluated to remove arsenic from water in the Pájaro Verde mine shaft, Huautla, Tlaquiltenango, Morelos. The media were synthesized and characterized, obtaining a surface area of 43.04 m2.g-1 for the goethite and 2.44 m2.g-1 for silica sand coated with Fe(III). To conduct the sorption kinetics and isotherms, a 23 factorial design was performed for each medium in order to obtain the optimal conditions for the factors of arsenic concentration, pH and mass of the adsorbent. The best results were obtained for goethite, with a removal efficiency of 98.61% (Co of As(V) 0.360 mg. L-1), and an effluent concentration of 0.005 mg. L-1, a value that complies with the modified Official Mexican Standard NOM-127-SSA1-1994 and WHO guidelines (2004). The kinetic equation that best fit the experimental data was the pseudo-second-order, resulting in the highest values for the constants for synthetic goethite, with a rate constant sorption of 4.019. g.mg-1. Min-1. With respect to the sorption isotherms, both media were fitted to the Langmuir-II linear model with a sorption capacity (qm) of 0.4822 mg. g-1 for goethite and 0.2494 mg. g-1 for silica sand coated with Fe(III).

Contaminación del agua Arsénico Remoción de contaminantes INGENIERÍA Y TECNOLOGÍA

La biofiltración sobre materiales orgánicos, nueva tecnología sustentable para tratar agua residual en pequeñas comunidades e industrias

Marco Antonio Garzón-Zúñiga Gerardo Buelna GABRIELA ELEONORA MOELLER CHAVEZ (2012, [Artículo])

El objetivo de este trabajo es presentar los resultados de las principales realizaciones a escala real de esta tecnología y su impacto en los sectores urbano (pequeños municipios, zonas rurales), agropecuario (granjas porcinas) y agroalimentario (rastros avícolas) en Canadá y México.

Biofiltración Tratamiento in situ Sistema de bajo mantenimiento Agua residual doméstica Agua residual industrial INGENIERÍA Y TECNOLOGÍA