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Vibrissa growth rate in California sea lions based on environmental and isotopic oscillations

MARTHA PATRICIA ROSAS HERNANDEZ (2018, [Artículo])

Pinniped vibrissae provide information on changes in diet at seasonal and annual scales; however, species-specific growth patterns must first be determined in order to interpret these data. In this study, a simple linear model was used to estimate the growth rate of vibrissae from adult female California sea lions (Zalophus californianus) from San Esteban Island in the Gulf of California, Mexico. The δ15N and δ13C values do not display a marked oscillatory pattern that would permit direct determination of the time period contained in each vibrissa; thus, time (age) was calculated in two ways: 1) based on the correlation between the observed number of peaks (Fourier series) in the δ15N profile and the length of each vibrissa, and 2) through direct comparison with the observed number of peaks in the δ15N profile. Cross-correlation confirmed that the two peaks in the δ15N profile reflected the two peaks in the chlorophyll-a concentration recorded annually around the island. The mean growth rate obtained from the correlation was 0.08 ± 0.01 mm d-1, while that calculated based on the observed number of peaks was 0.10 ± 0.05 mm d-1. Both are consistent with the rates reported for adult females of other otariid species (0.07 to 0.11 mm d-1). Vibrissa growth rates vary by individual, age, sex, and species; moreover, small differences in the growth rate can result in significant differences over the time periods represented by the isotopic signal. Thus, it is important to assess this parameter on a species-by-species basis. © 2018 Rosas-Hernández 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.

carbon, nitrogen, animal, California, chemistry, diet, female, island (geological), Mexico, Otariidae, physiology, Animals, California, Carbon Isotopes, Diet, Female, Islands, Mexico, Nitrogen Isotopes, Sea Lions BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA INMUNOLOGÍA INMUNOLOGÍA

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

Rainfall water quality at Atlixco, Puebla

Margarita Teutli Andrés Armando Sánchez Erendira Moreno Gutierrez (2021, [Artículo, Artículo])

This work reports the follow up of rainfall water quality at Atlixco, Puebla during the 2018 season. The main objective of this work was to evaluate how height and pollutants define the quality of water precipitated. Samples were collected at the roof of a house in Atlixco center, and others at the roof of a convent located at the San Miguel Hill, this represents a 44 m difference in height. Chemical composition was analyzed for 19 physicochemical parameters using gravimetric and spectrophotometric techniques. Obtained results were compared with drinking water standards finding that Pb and Cd contents are exceeded. Also, it was found a strong contribution of terrestrial sources since the marine rates are above unit, as well as excess concentrations whose values go from negative to positive. Finally, Pearson correlation was obtained finding that most of chemical parameters correlations are in disagreement for both sites, fact which confirms that ionic content is strongly influenced by anthropogenic sources.

rainfall ionic content marine rates excess concentrations Lluvia contenido iónico cociente marino concentración en exceso Estudios urbanos CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA

Mainländeriana I

LUIS ALONSO GERENA CARRILLO SERGIO RODRIGO LOMELI GAMBOA (2023, [Libro])

La filosofía de la redención (1876), de Philipp Mainländer, fue prácticamente ignorada por los filósofos de su tiempo. Sin embargo, los problemas que enfrentamos en la actualidad –el cambio climático, la violencia– han llevado a los estudiosos a rescatar la originalidad de esta obra. En concordancia con esta tendencia, en este libro lo que nos reúne es la necesidad de visibilizar la vigencia del pensamiento de Mainländer para dialogar sobre lo que con urgencia nos aqueja, pero también mostrar su relación con otros filósofos, así como expo- siciones de sus tesis filosóficas. De acuerdo con esto, Fernando Burgos, Sandra Baquedano Jer y Luis Alonso Gerena Carrillo actualizan la obra mainländeriana desde una mirada actual partiendo desde la ética ambiental, la política y la educación. En otra sección podemos encontrar la relación que guarda con otros pensadores, y entre estos ensayos se encuentra el de Fabio Ciracì, quien expone a Mainländer y a Schopenhauer como lectores de Leopardi. Rodolfo Esteban Tapia encuentra un vínculo analógico entre el humorista mainländeriano y el Fausto de Goethe. Manuel Pérez Cornejo también nos ofrece la distinción estética que existe entre Schopen- hauer y Mainländer. Por último, tenemos algunas exposiciones del sistema mainländeriano, las cuales son imprescindibles para entender su obra. Entre estos textos contamos con los de Fernando Flores Bailón, H. W. Gámez, Paolo Gajardo Jaña, Héctor Fabio García Libreros y René Quintanilla.

HUMANIDADES Y CIENCIAS DE LA CONDUCTA FILOSOFÍA

Variaciones del pragmatismo en la filosofía contemporánea

JOSE MIGUEL ESTEBAN CLOQUELL (2006, [Libro])

Como atestiguan varios de los escritos que John Dewey realizó para el desarrollo del pragmatismo, un buen trecho de la evolución de lo que hoy se llama pragmatismo clásico puede interpretarse como una serie de esfuerzos por refinar lo que esta variante filosófica fue llamando práctica, prácticas y práctico. Fue Dewey quien reconstruye el debate sobre estos tres conceptos y los eleva a categorías ontológicas. En este libro el autor pretende reactualizar algunas de las aportaciones deweyanas al análisis de la práctica y las prácticas humanas, así como sugerir su vigencia y pertinencia en el giro contemporáneo de estos conceptos, por lo que resulta necesario también enfrentar, comparar y analizar las nociones de otros autores que entraron en el debate, tales como Stephen Turner, Kant, Peirce, entre otros.

HUMANIDADES Y CIENCIAS DE LA CONDUCTA FILOSOFÍA pragmatismo

Internal erosion under spillway rested on an embakment dam

JOSE RAUL FLORES BERRONES (2015, [Artículo])

This paper presents the investigation about the mechanism of internal erosion caused in the right abutment of the Shahghasem dam’s spillway. Shahghasem dam is an earthen dam located in Yasouj, in southwest of Iran. A significant hole and pipe have been observed in the corner of the right abutment from upstream view. The foundation is Marlstone, which has low cohesion and susceptible for internal erosion and piping in some conditions. Going through details of the design maps has shown that Lane’s criteria for selecting safe dimensions of the seepage control measures have not been considered properly. A series of the supportive walls are designed to attach to the right part of the spillway in order to increase the length of seepage. The pipe route of the erosion should also be grouted with high quality concrete.

Erosión del suelo Aliviaderos Presas Filtración INGENIERÍA Y TECNOLOGÍA

Desarrollo de un sistema piloto de aprovechamiento de agua residual tratada para cría de peces de ornato, con descarga cero

LUCIANO SANDOVAL YOVAL (2011, [Documento de trabajo])

Tabla de contenido: Antecedentes: Filtración; filtración en múltiples etapas; tezontle en Morelos; acuicultura – Justificación – Objetivos – Metodología – Resultados: Sistema de filtración; especies de peces en tanques de monitoreo; determinación de parámetros de control del sistema de filtración – Análisis de resultados – Conclusiones – Recomendaciones.

Antecedentes: Filtración; filtración en múltiples etapas; tezontle en Morelos; acuicultura – Justificación – Objetivos – Metodología – Resultados: Sistema de filtración; especies de peces en tanques de monitoreo; determinación de parámetros de control del sistema de filtración – Análisis de resultados – Conclusiones – Recomendaciones.

Tratamiento de aguas residuales Filtración Peces de ornato Informes de proyectos INGENIERÍA Y TECNOLOGÍA

Coinfection and in vitro interaction of Lasiodiplodia pseudotheobromae and Pestalotiopsis mangiferae associated with dieback in branches of mango (Mangifera indica) Manila variety, in Veracruz, Mexico

LILIANA EUNICE SAUCEDO PICAZO Luis Guillermo Hernández Montiel NORMA FLORES ESTEVEZ PATRICIA GEREZ FERNANDEZ ANGEL FERNANDO ARGÜELLO ORTIZ JUAN CARLOS NOA CARRAZANA (2022, [Artículo])

"Dieback disease caused by fungal complexes is a severe problem in mango trees (Mangifera indica). Its main symptoms are branch rot, gummosis, and finally, the tree’s death. In this work, the species of the fungal complex causing mango dieback in the Manila variety in Veracruz, Mexico were identified. The in vitro interaction of two species belonging to the complex was evaluated and the severity of the co-infection in mango branches. Lasiodiplodia pseudotheobromae and Pestalotiopsis mangiferae were identified as causal agents of mango dieback in the producing area of Veracruz. In coinfected mango branches, greater severity of necrosis was observed than in individual infections. Liquid culture filtrates applied in co-cultures showed different results for each species of phytopathogen. The P. mangiferae filtrate had no significant antagonistic effects on the growth of L. pseudotheobromae (inhibition of 2.68%), while the L. pseudotheobromae filtrate inhibited 41.38% of P. mangiferae. The results show that multiple infections in mango trees increase the damage caused by dieback, which could directly impact the development of control strategies."

gummosis, virulence, interaction, fungal complex CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CIENCIAS AGRARIAS FITOPATOLOGÍA FITOPATOLOGÍA FITOPATOLOGÍA

Potential of Debaryomyces hansenii Strains on the Inhibition of Botrytis cinerea in Blueberry Fruits (Vaccinium corymbosum L.)

SURELYS RAMOS BELL Luis Guillermo Hernández Montiel RITA MARIA VELAZQUEZ ESTRADA JUAN ANTONIO HERRERA GONZALEZ PORFIRIO GUTIERREZ MARTINEZ (2022, [Artículo])

"Blueberry (Vaccinium corymbosum L.) is a crop with great potential for exportation and is very important for its antioxidant properties. However, this fruit is susceptible to different factors of deterioration and attack by pathogens. Botrytis cinerea is the main cause of post-harvest losses in this crop. Antagonistic yeasts from the Debaryomyces hansenii species, which is of marine origin, have been proposed as an alternative method for fungal control. For this reason, this study evaluated the in vitro and in vivo antagonistic capacity of the yeast against B. cinerea. The in vitro growth of the fungus was inhibited by 90% and germination was reduced by 100%, and through the production of volatile organic compounds, the growth of the pathogen was inhibited by 32.5%. Photographic evidence by electron microscopy revealed the effects caused by D. hansenii on B. cinerea. The incidence study showed a 50% reduction in the incidence of the disease caused by B. cinerea in blueberries, while quality parameters—such as soluble solids, titratable acidity, and pH—presented stable values, delaying the maturation process of the fruits. Likewise, the rate of reduction in firmness and physiological weight loss was lower, and the blueberries preserved their quality for a longer time."

Debaryomyces hansenii, blueberry, gray mold, postharvest quality CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CIENCIAS AGRARIAS FITOPATOLOGÍA FITOPATOLOGÍA FITOPATOLOGÍA

Waterhole detection using a vegetation index in desert bighorn sheep (Ovis canadensis cremnobates) habitat

Jonathan Gabriel Escobar Flores (2019, [Artículo])

In arid ecosystems, desert bighorn sheep are dependent on natural waterholes, particularly in summer when forage is scarce and environmental temperatures are high. To detect waterholes in Sierra Santa Isabel, which is the largest area of desert bighorn sheep habitat in the state of Baja California, Mexico, we used the normalized difference vegetation index (NDVI) and normalized difference water index (NDWI) from Sentinel-2 satellite images. Waterhole detection was based on the premise that sites with greater water availability, where NDVI was higher, can be identified by their density of vegetation greenness. For the detected waterholes, we estimated the escape terrain (presence of cliffs or steep, rocky slopes) around each by the vector ruggedness measure to determine their potential use by desert bighorn sheep based on the animals’ presence as documented by camera traps. We detected 14 waterholes with the NDVI of which 11 were known by land owners and 3 were unrecorded. Desert bighorn were not detected in waterholes with high values of escape terrain, i.e., flat areas. Waterhole detection by NDVI is a simple method, and with the assistance and knowledge of the inhabitants of the Sierra, it was possible to confirm the presence each waterhole in the field. © 2019 Escobar-Flores 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.

Article, bighorn sheep, environmental aspects and related phenomena, environmental parameters, habitat, Mexico, nonhuman, normalized difference vegetation index, normalized difference water index, water availability, waterhole, animal, bighorn sheep, CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CIENCIAS AGRARIAS CIENCIA FORESTAL CIENCIA FORESTAL