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APLICACIÓN DE METAHEURÍSTICAS EN EL PROBLEMA DE ACOMODO DE PATRONES DE CORTE EN MATERIALES FINITOS

Anabel Rodríguez Rodríguez (2023, [Tesis de doctorado])

"En la presente investigación se resuelve el problema de optimización de acomodo de patrones de corte en materiales finitos mediante el uso de estrategias metaheurísticas con la finalidad de aprovechar el material de acomodo y minimizar el desperdicio. Específicamente se implementó un algoritmo genético que al inicio genera soluciones aleatorias que forman la población inicial. La misma está compuesta por individuos o soluciones que son una combinación de patrones que se acomodan dentro del material de manera que se obtenga el menor desperdicio. Durante el proceso evolutivo estas soluciones aleatorias se someten a los operadores genéticos: selección, cruce y mutación, para encontrar nuevas soluciones que hereden la información genética de sus antecesores y evolucionen o mejoren en cada generación para obtener el menor desperdicio posible."

Acomodo de patrones Algoritmos genéticos Algoritmos golosos Muéganos Metaheurísticas Procesamiento digital de imágenes INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS OTRAS ESPECIALIDADES TECNOLÓGICAS OTRAS OTRAS

Assessing the Spatiotemporal Relationship between Coastal Habitats and Fish Assemblages at Two Neotropical Estuaries of the Mexican Pacific

VICTOR MANUEL MURO TORRES FELIPE AMEZCUA MARTINEZ Gerogina Ramírez Ortiz FRANCISCO JAVIER FLORES DE SANTIAGO Felipe Amezcua Linares Yareli Hernández Álvarez (2022, [Artículo])

"Differences in fish assemblages’ structures and their relations with environmental variables (due to the variations in sampled seasons, habitats, and zones) were analyzed in two adjacent estuaries on the north Pacific coast of Mexico. Environmental variables and fish catches were registered monthly between August 2018 and October 2020. Multivariate analyses were conducted to define habitats and zones based on their environmental characteristics, and the effect of this variability on fish assemblages’ composition, biomass, and diversity (α and β) was evaluated. A total of 12,008 fish individuals of 143 species were collected using different fishing nets. Multivariate analyses indicated that fish assemblages’ structures were different between zones due to the presence, height, and coverage of distinct mangrove species. Additionally, depth and salinity showed effects on fish assemblages’ diversity (α and β-nestedness), which presented higher values in the ocean and remained similar in the rest of the analyzed zones and habitats. These results and the differences in species replacement (β-turnover) indicate the singularity of fish assemblages at estuaries (even in areas close to the ocean) and the necessity to establish local management strategies for these ecosystems."

mangrove forests, marine protected areas, alpha diversity, beta diversity, multivariate analyses CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CIENCIAS AGRARIAS PECES Y FAUNA SILVESTRE DINÁMICA DE LAS POBLACIONES DINÁMICA DE LAS POBLACIONES

The Chemical Evolution of Narrow Emission Line Galaxies: the Key to their Formation Processes

JUAN PABLO TORRES PAPAQUI ROGER COZIOL RENE ALBERTO ORTEGA MINAKATA (2011, [Artículo])

Using the largest sample of narrow emission line galaxies available so far, we show that their spectral characteristics are correlated with different physical parameters, like the chemical abundances, the morphologies, the masses of the bulge and the mean stellar age of the stellar populations of the host galaxies. It suggests that the spectral variations observed in standard spectroscopic diagnostic diagrams are not due solely to variations of ionization parameters or structures but reflect also the chemical evolution of the galaxies, which in turn can be explained by different galaxy formation processes.

Utilizando la mayor muestra de galaxias con líneas de emisión angostas disponible hasta el momento, se muestra que sus características espectrales están correlacionadas con diferentes parámetros físicos, como las abundancias químicas, las morfologías, las masas del bulbo, y la edad estelar promedio de las poblaciones estelares de la galaxia anfitrio-na. Por lo tanto, se sugiere que las variaciones espectrales observadas en diagramas de diagnóstico estándares no se deben únicamente a las variaciones de los parámetros o las estructuras de ionización, sino que reflejan también la evolución química de las galaxias, relacionada con diferentes procesos de formación

CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA Galaxy Chemical Activity Formation Chemical evolution Galaxias Actividad química Formación Evolución química

Strong floristic distinctiveness across Neotropical successional forests

Catarina Jakovac Jorge Arturo Meave del Castillo Frans Bongers Susan Letcher JUAN MANUEL DUPUY RADA Daniel Piotto Danaë Rozendaal Marielos Peña-Claros Dylan Craven Braulio Santos Alexandre Siminski Alfredo Fantini Alice Cristina Rodrigues Alma Hernandez-Jaramillo Álvaro Idárraga-Piedrahita André Junqueira Angelica Almeyda Zambrano Bernardus de Jong Bruno X. Pinho Bryan Finegan Carolina Castellanos Castro Daisy Christiane Zambiazi Daisy Dent Daniel Hernán Garcia-Villalobos Deborah Kennard Diego Delgado Eben Broadbent Edgar Ortiz-Malavasi Eduardo A. Pérez-García Edwin Lebrija-Trejos Erika Berenguer Erika Marin-Spiotta Esteban Alvarez_Davila EVERARDO VALADARES DE SÁ SAMPAIO Felipe Melo Fernando Elias Filipe França Florian Oberleitner Francisco Mora Ardila G. Bruce Williamson Gabriel Colletta George Cabral Geraldine Derroire Geraldo Fernandes Hans van der Wal Heitor Mancini Teixeira Henricus F.M. Vester Hernando Garcia Ima Vieira Jaider Jiménez-Montoya Jarcilene Almeida Cortez Jefferson Hall Jerome Chave Jess Zimmerman Jhon Edison Nieto Vargas Joice Ferreira JORGE ENRIQUE RODRIGUEZ VELAZQUEZ Jorge Ruiz Jos Barlow Jose Aguilar Cano JOSE LUIS HERNANDEZ STEFANONI Julien Engel Justin Becknell Kátia Janaina Zanini Madelon Lohbeck Marcelo Tabarelli Marco Antonio Romero Romero Maria Uriarte Maria das Dores Magalhães Veloso Mário do Espírito Santo Masha van der Sande Michiel van Breugel Miguel Martínez-Ramos Naomi Schwartz Natalia Norden Nathalia Pérez-Cárdenas Noel Antonio González_Valdivia PASCAL PETRONELLI Patricia Balvanera Paulo Massoca Pedro Brancalion Pedro Manuel Villa Peter Hietz Rebecca Ostertag René López Camacho Ricardo Cesar Rita Mesquita Robin Chazdon Rodrigo Muñoz Saara DeWalt Sandra Müller Sandra M Duran Sebastião Martins Susana Ochoa-Gaona Susana Rodriguez-Buritica T. Mitchell Aide Tony Vizcarra Bentos Vanessa de Souza Moreno Laura Vanessa Granda William Thomas Whendee Silver YULE NUNES Lourens Poorter (2022, [Artículo])

Forests that regrow naturally on abandoned fields are important for restoring biodiversity and ecosystem services, but can they also preserve the distinct regional tree floras? Using the floristic composition of 1215 early successional forests (≤20 years) in 75 human-modified landscapes across the Neotropic realm, we identified 14 distinct floristic groups, with a between-group dissimilarity of 0.97. Floristic groups were associated with location, bioregions, soil pH, temperature seasonality, and water availability. Hence, there is large continental-scale variation in the species composition of early successional forests, which is mainly associated with biogeographic and environmental factors but not with human disturbance indicators. This floristic distinctiveness is partially driven by regionally restricted species belonging to widespread genera. Early secondary forests contribute therefore to restoring and conserving the distinctiveness of bioregions across the Neotropical realm, and forest restoration initiatives should use local species to assure that these distinct floras are maintained. Copyright © 2022 The Authors, some rights reserved.

CONSERVATION ECOSYSTEMS FORESTRY BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOLOGÍA VEGETAL (BOTÁNICA) ECOLOGÍA VEGETAL ECOLOGÍA VEGETAL

Metals pollution in El Limón lagoon, Chiapas, Mexico

MARIA TERESA LEAL ASCENCIO SAUL MIRANDA ALONSO Elena María Otazo Sanchez Francisco Prieto García (2009, [Artículo])

La laguna El Limón, en el municipio de Reforma, Chiapas, México, ha presentado mortandad masiva de peces, lo que llevó a realizar un estudio más profundo que determinara el grado de contaminación de la laguna, así como las causas posibles de los eventos. Los resultados muestran que en los sedimentos de la laguna las concentraciones promedio de Zn, Ni, Cr, Cd y Cu rebasan los límites recomendados en Canadá y Estados Unidos para evitar la aparición de efectos biológicos nocivos en especies acuáticas. Es de especial mención la acumulación de Zn, que presenta una concentración máxima de 1360 mg/kg, presumiblemente asociada al uso de este metal como catalizador en una planta procesadora de gas. Si bien las descargas industriales que vierten a la laguna cumplen con los estándares establecidos en México para metales, esto no ha sido suficiente para evitar su acumulación en los sedimentos, lo cual demuestra que las normas existentes para las descargas de aguas residual industrial deben aumentar sus restricciones y tomar en cuenta el tipo de cuerpo receptor al que vierten. En el caso del uso de agua residual o contaminada para riego, la acumulación puede darse en los suelos agrícolas, pasando eventualmente a los cultivos, lo que tampoco es deseable.

Lagunas Contaminación del agua Metales Zinc INGENIERÍA Y TECNOLOGÍA

Influence of conservation agriculture-based production systems on bacterial diversity and soil quality in rice-wheat-greengram cropping system in eastern Indo-Gangetic Plains of India

Anup Das virender kumar Peter Craufurd Andrew Mcdonald Sonam Sherpa (2023, [Artículo])

Introduction: Conservation agriculture (CA) is gaining attention in the South Asia as an environmentally benign and sustainable food production system. The knowledge of the soil bacterial community composition along with other soil properties is essential for evaluating the CA-based management practices for achieving the soil environment sustainability and climate resilience in the rice-wheat-greengram system. The long-term effects of CA-based tillage-cum-crop establishment (TCE) methods on earthworm population, soil parameters as well as microbial diversity have not been well studied. Methods: Seven treatments (or scenarios) were laid down with the various tillage (wet, dry, or zero-tillage), establishment method (direct-or drill-seeding or transplantation) and residue management practices (mixed with the soil or kept on the soil surface). The soil samples were collected after 7 years of experimentation and analyzed for the soil quality and bacterial diversity to examine the effect of tillage-cum-crop establishment methods. Results and Discussion: Earthworm population (3.6 times), soil organic carbon (11.94%), macro (NPK) (14.50–23.57%) and micronutrients (Mn, and Cu) (13.25 and 29.57%) contents were appreciably higher under CA-based TCE methods than tillage-intensive farming practices. Significantly higher number of OTUs (1,192 ± 50) and Chao1 (1415.65 ± 14.34) values were observed in partial CA-based production system (p ≤ 0.05). Forty-two (42) bacterial phyla were identified across the scenarios, and Proteobacteria, Actinobacteria, and Firmicutes were the most dominant in all the scenarios. The CA-based scenarios harbor a high abundance of Proteobacteria (2–13%), whereas the conventional tillage-based scenarios were dominated by the bacterial phyla Acidobacteria and Chloroflexi and found statistically differed among the scenarios (p ≤ 0.05). Composition of the major phyla, i.e., Proteobacteria, Actinobacteria, and Firmicutes were associated differently with either CA or farmers-based tillage management practices. Overall, the present study indicates the importance of CA-based tillage-cum-crop establishment methods in shaping the bacterial diversity, earthworms population, soil organic carbon, and plant nutrient availability, which are crucial for sustainable agricultural production and resilience in agro-ecosystem.

Metagenomics Bacterial Diversity Rice-Wheat-Greengram CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CONSERVATION AGRICULTURE DNA SEQUENCES EARTHWORMS METAGENOMICS SOIL QUALITY AGROECOSYSTEMS