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Changes in soil organic carbon pools after 15 years of Conservation Agriculture in rice (Oryza sativa)-wheat (Triticum aestivum) cropping system of eastern Indo-Gangetic plains

C.M. Parihar Mahesh Gathala ML JAT (2023, [Artículo])

The present study was carried out at Dr. Rajendra Prasad Central Agricultural University, Samastipur, Bihar during 2021-2023 to focus on examining alterations in SOC pools resulting from conservation agriculture (CA) practices in R-W system in the eastern IGP, following the collection of soil samples from a long-term trial that was initiated in rainy (kharif) season 2006. The trial included eight combinations, namely: conventional tilled rice (Oryza sativa L.) and wheat (Triticum aestivum L.) (CTR-CTW); CT rice and zero till wheat (CTR-ZTW); direct seeded rice (DSR) and wheat on permanent raised beds (PBDSR-PBW); ZTDSR and CT Wheat (ZTDSR-CTW); ZTDSR and ZT wheat without residue (ZTDSR-ZTW-R); ZTDSR-ZT wheat with residue (ZTDSR-ZTW +R); unpuddled transplanted riceZTW (UpTR-ZTW) and ZTDSR-sesbania brown manure-ZTW (ZTDSR-S-ZTW). Results revealed that implementing zero tillage (ZT) combined with residue retention in rice and wheat cultivation led to enhanced levels of soil organic carbon (SOC) across all four fractions, namely very labile (CVL), labile (CL), less labile (CLL), and non-labile (CNL), in comparison to the continuous and rotational tillage practices. The tillage and residue management options significantly affected the lability index (LI) and C pool index (CPI), with zero-tillage and residue retention leading to lower LI and higher CPI values. The management practices significantly affected the C management index (CMI), with zero-tillage and residue retention showing the highest CMI values. Findings showed the potential of CA practices for enhancing soil C quality as well as C sequestration in soil of the Eastern IGP of India.

Carbon Management Index Soil Organic Carbon Fractions CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CONSERVATION AGRICULTURE SOIL ORGANIC CARBON ZERO TILLAGE

Casos de estudio en México en el sector de la construcción

Aurora Poó Rubio (2010, [Artículo])

El planeamiento del estudio de casos múltiples para estudiar las empresas en el sector de la construcción permitió a la presente investigación el examen del comportamiento de varias empresas. Aunque estas no eran completamente similares, su comparación pudo ser llevada a cabo, identificando prácticas exitosas, así como aquellas que derivaron en grandes problemas para las organizaciones. Referente a la evaluación, las empresas no necesariamente cumplieron completamente con todas las premisas planteadas en sus hipótesis de trabajo. Se observó que las organizaciones estudiadas tuvieron un comportamiento diferenciado. SIDEK, tuvo aciertos espectaculares, pero igual de impactante fueron sus contratiempos. Se desempeñó hasta el 94 como una gran empresa, pero en la segunda mitad de los 90's produjo resultados contrastantes. ARA respondió satisfactoriamente a todas las evaluaciones aplicadas y su desempeño ha continuado siendo exitoso, basado en políticas de trabajo y financieras visionarias pero conservadoras al mismo tiempo, lo que pone en manifiesto las experiencias vividas en los años de crisis económica del país. ICA fue sumamente exitosa durante un importante período de tiempo y sufrió fuertes afectaciones por los cambios contextuales, anotados en el estudio correspondiente; identifica tanto áreas disfuncionales como momentos en el tiempo de fragilidad empresarial; actualmente con la generación de obra pública y el Programa Nacional de Infraestructura, su desempeño ha vuelto a ser exitoso y se mantiene como la constructora número 1 del país. En nuestro país son pocos los Casos de Estudio de empresas mexicanas y no se localizó ninguna información respecto a firmas del sector de la construcción. Lo anterior muestra que hay un gran camino que recorrer en cuanto al estudio de las firmas por estos medios y que el diagnóstico que se puede elaborar de su desempeño es fundamental para el diseño de la Planeación Estratégica de las empresas del sector de la construcción en México.

Construction industry--Mexico. Construction industry--Management. Industria de la construcción -- Administración. HD9715.M4 CIENCIAS SOCIALES CIENCIAS ECONÓMICAS ECONOMÍA SECTORIAL CONSTRUCCIÓN

Weed management and tillage effect on rainfed maize production in three agro-ecologies in Mexico

Simon Fonteyne Abel Jaime Leal González Rausel Ovando Ravi Gopal Singh Nele Verhulst (2022, [Artículo])

Maize (Zea mays L.) is grown in a wide range of agro-ecological environments and production systems across Mexico. Weeds are a major constraint on maize grain yield, but knowledge regarding the best weed management methods is lacking. In many production systems, reducing tillage could lessen land degradation and production costs, but changes in tillage might require changes in weed management. This study evaluated weed dynamics and rainfed maize yield under five weed management treatments (pre-emergence herbicide, post-emergence herbicide, pre-emergence + post-emergence herbicide, manual weed control, and no control) and three tillage methods (conventional, minimum and zero tillage) in three agro-ecologically distinct regions of the state of Oaxaca, Mexico, in 2016 and 2017. In the temperate Mixteca region, weeds reduced maize grain yields by as much as 92% and the long-growing season required post-emergence weed control, which gave significantly higher yields. In the hot, humid Papaloapan region, weeds reduced maize yields up to 63% and pre-emergence weed control resulted in significantly higher yields than treatments with post-emergence control only. In the semi-arid Valles Centrales region, weeds reduced maize yields by as much as 65%, but weed management was not always effective in increasing maize yield or net profitability. The most effective weed management treatments tended to be similar for the three tillage systems at each site, although weed pressure and the potential yield reduction by weeds tended to be higher under zero tillage than minimum or conventional tillage. No single best option for weed management was found across sites or tillage systems. More research, in which non-chemical methods should not be overlooked, is thus needed to determine the most effective weed management methods for the diverse maize production systems across Mexico.

Corn Integrated Weed Management Manual Weed Control CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA MAIZE WEED CONTROL MINIMUM TILLAGE ZERO TILLAGE

Determinantes del comportamiento de queja del consumidor en México

Determinants of consumer complaint behavior in Mexico

IGNACIO JAVIER CRUZ RODRIGUEZ JAVIER GALAN FIGUEROA (2019, [Artículo])

El objetivo del trabajo es explicar los determinantes del comportamiento de queja del consumidor en los niveles socioeconómico y empresa. Para ello se acude a la metodología de datos de panel estático a fin de estimar el impacto de los determinantes de las quejas de los consumidores. Los resultados a nivel socioeconómico indican que las quejas se encuentran determinadas por el ingreso, las conciliaciones a favor de los consumidores y por la población residente en zonas urbanas. Mientras a nivel empresa los resultados muestran que tanto la cuota de mercado como el tamaño de la firma afectan positivamente las quejas. Se concluye que los resultados coinciden con la literatura revisada y que se puede esperar un aumento en el número de quejas presentadas por los consumidores.

This work aims to quantify the determinants of consumer complaint behavior in socioeconomic and business levels. For this purpose, the static panel data methodology is used in order to estimate the impact of consumer complaints both at the federal level of the Mexican Republic and at the level of the main companies that are considered leaders in their field. The results by the state indicate that the complaints are determined by income, reconciliations in favor of consumers and population residing in urban areas.While at the company level, the results show that both market share and company size positively affect consumer complaints. In conclusion, the results agree with the literature reviewed, and a rise in the number of complaints is possible.

HUMANIDADES Y CIENCIAS DE LA CONDUCTA Datos de panel Efectos fijos y efectos aleatorios Satisfacción de los consumidores Quejas del consumidor Panel data models Fixed effects and random effects Consumer complaint

Remedies for the Inconsistences in the Times of Execution of the Unsorted Database Search Algorithm within the Wave Approach

Manuel Ávila Aoki José Benito Elizalde Salas (2017, [Artículo])

The typical semiclassical wave version of the unsorted database search algorithm based on a system of coupled simple harmonic oscillators does not consider an important ingredient of Grovers original algorithm as it is quantum entanglement. The role of entanglement in the wave version of the unsorted database search algorithm is explored and contradictions with the time of execution of Grovers algorithm are found. We remedy the contradictions by employing two arguments, one of them qualitative and the other quantitative. For the qualitative argument we employ the probabilistic nature of a legitimate quantum algorithm and remedy the above inconsistence. Within the quantitative argument we identify a parameter in the wave version of the unsorted database search algorithm which is related to entanglement. The contradiction with the time of execution of Grovers algorithm is solved by choosing an appropriate values of such a parameter which incorporates entanglement to the wave version of the unsorted database search algorithm. The utility of the present arguments are evident if the wave version of the unsorted data base search algorithm is experimentally implemented through a system of N quantum dots with a harmonic oscillator potential as a confinement potential for each of the quantum dots. Each of the above N vibrating quantum dots must be coupled to an extra single vibrating quantum dot which entangles to all of them. In order to obtain optimal results, the coupling constants of the mentioned quantum dots should be adjusted in the way described in the present work.

Computación Unsorted database search Grover algorithm wave entanglement queries time Computación Unsorted database search Grover algorithm wave entanglement queries time INGENIERÍA Y TECNOLOGÍA

Efficiency of combating property violence in the Northwest region of Mexico

Martin Flegl Eva Selene Hernández Gress (2023, [Artículo, Artículo])

The situation of violence in Mexico shows an alarming trend as the number of committed crimes increased by 10.9% in 2021 compared to 2020. In fact, 75.6% of the Mexican population perceives the insecurity. Due to the above, it is necessary to strengthen public security to combat this trend. However, the resources allocated to the public security in Mexico are limited. Although there are studies that investigate what causes the violence in Mexico, so far there is no study that measures the efficiency of combating the violence related to budgetary, human, and material resources of the public security. This article investigates the efficiency of combating the property violence in 206 municipalities in the Northwest region of Mexico through the Data Envelopment Analysis. The results show a low efficiency (56.67%) with significant differences between the states in the region. Baja California is the state with the lowest efficiency (17.61%), whereas the highest efficiency is found in Durango (67.25%). For the last, the need to carefully plan changes in the police force and the public security infrastructure was noted to improve the efficiency and the level of security.

Análisis Envolvente de Datos Delincuencia Eficiencia Municipios Seguridad pública CIENCIAS SOCIALES CIENCIAS SOCIALES Data Envelopment Analysis Delinquency Public security

Desarrollo sostenible de la gestión escolar: un proceso en tensión

Raúl Enrique Anzaldúa (2004, [Capítulo de libro])

Capítulo de la sección: Educación y sustentabilidad

En este trabajo se intentará abordar, aunque sea de manera esquemática, una aproximación a ciertos aspectos de la crisis que se presenta en el subsistema de educación básica, especialmente aquellos aspectos vinculados con la gestión escolar. enmarcada en las tensiones provocadas por el dispositivo pedagógico que se ha establecido para el ejercicio del poder en este ámbito educativo.

Basic education--Mexico. School management and organization--Mexico. Education and state--Mexico. Educación básica. Administración escolar. LC1035.8.M6 HUMANIDADES Y CIENCIAS DE LA CONDUCTA PEDAGOGÍA ORGANIZACIÓN Y PLANIFICACIÓN DE LA EDUCACIÓN ORGANIZACIÓN Y DIRECCIÓN DE LAS INSTITUCIONES EDUCATIVAS

Dormitator latifrons (Richardson, 1844) a Pacific fat sleeper, but skinny in research: a scientometric study

MARTIN ALONSO ARECHIGA PALOMERA KAREN NOEMI NIEVES RODRIGUEZ OLIMPIA CHONG CARRILLO Héctor Gerardo Nolasco Soria Emyr Saúl Peña Marín Carlos Alfonso Alvarez_González DAVID JULIAN PALMA CANCINO RAFAEL MARTINEZ GARCIA DANIEL BADILLO ZAPATA FERNANDO VEGA VILLASANTE (2022, [Artículo])

"In order to provide information on the current knowledge about the native fish Dormitator latifrons and identify the gaps that must be filled to achieve correct resource management, a scientometric study was carried out using different scientific databases. A total of 103 publications were registered between the years 1972 and 2021. Results indicate that the species has been addressed since 2001 with less than one publication per year, with 2008 being the year with the highest number of publications (10). The main topics addressed were ecology, physiology, and parasitology of fish. The available knowledge generated about the species is concentrated in 68 journals, with Mexico as the most productive country, followed by USA and Ecuador, and the most productive research centers about this fish were Mexico’s Instituto Politécnico Nacional and Universidad de Guadalajara. A total of 285 authors were detected contributing knowledge to the species, with Violante-González in the top with ten publications. The co-authorship co-occurrence maps suggest there is no solid collaborative relationship between the scientific community and that the information generated is insufficient for conserving and exploiting this fish. It is essential to increase the study of thematic areas that allow their comprehensive management in the medium term; topics like reproduction in captivity, aquaculture, and nutrition must be addressed in the future to assure a sustainable use of this resource."

Dormitator latifrons, native fish, amphidromous, worldwide database, regional database, cooccurrence map CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CIENCIAS AGRARIAS PECES Y FAUNA SILVESTRE DINÁMICA DE LAS POBLACIONES DINÁMICA DE LAS POBLACIONES

ANÁLISIS DE LA APTITUD RECREATIVA ORIENTADA A LA GESTIÓN AMBIENTAL DE LA PLAYA EL COCHÓRIT, SONORA, MÉXICO

GISELA GARCIA MORALES PEDRO ROSALES GRANO Gustavo Padilla Jose Alfredo Arreola Lizárraga Jaqueline García Hernández Alfredo Ortega Rubio Renato Arturo Mendoza Salgado (2017, [Artículo])

"La evaluación de la aptitud recreativa de playas es un asunto clave para diseñar estrategias de manejo. El objetivo de este estudio fue evaluar la aptitud recreativa y proponer una estrategia de manejo en la playa El Cochórit, municipio de Empalme, Sonora. La aptitud recreativa de la playa se evaluó con base en la percepción de los usuarios y en indicadores biofísicos. El valor estimado de la aptitud recreativa de la playa, según la percepción de los usuarios fue de 0.71 (medio) y con base en los indicadores biofísicos fue de 0.47 (medio). La aptitud recreativa de la playa requiere ser mejorada con atención prioritaria en: (1) inversión en infraestructura y servicios, (2) mantenimiento de limpieza, (3) implementación de programas de educación ambiental y (4) monitoreo anual de la calidad sanitaria del agua y de la arena. La estrategia de gestión ambiental debe considerar incluir a la playa El Cochórit en el Programa Playas Limpias de la Comisión Nacional del Agua con el propósito de orientar esfuerzos hacia su certificación como “playa limpia”."

"The assessment of recreational beaches fitness is a key issue to design management strategies. The aim of this work was to evaluate the recreational fitness and propose a management strategy for the Beach El Cochórit, municipality of Empalme, Sonora. The recreational beach fitness was evaluated based on the perception of users, as well as biophysical indicators. The estimated value of recreational suitability of the beach perceived by users was 0.71 (average) and based on the biophysical indicators was 0.47 (average). Fitness recreational beach needs to be improved focusing on: (1) investing in infrastructure and services, (2) maintaining cleanliness, (3) implementing environmental education programs and (4) monitoring annually the sanitary quality of water and sand. The environmental management strategy should consider including the beach El Cochorit in the Clean Beaches Program of the National Water Commission in order to address efforts towards the certification of “clean beach”."

playas recreativas, manejo de playas, indicadores ambientales, percepción pública recreational beaches, management of beaches, environmental indicators, public perception CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA CIENCIAS DE LA TIERRA Y DEL ESPACIO GEOLOGÍA GEOLOGÍA AMBIENTAL GEOLOGÍA AMBIENTAL