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La paradoja del hierro

Elizabeth Brassea Pérez VANESSA LABRADA MARTAGON JOSÉ PABLO VÁZQUEZ MEDINA Ramón Gaxiola Robles CLAUDIA JANETL HERNANDEZ CAMACHO TANIA ZENTENO SAVIN (2022, [Artículo])

"El hierro (Fe) es un micromineral abundante en nuestro planeta, el cual participa en procesos biológicos importantes como el transporte de oxígeno en la sangre y la formación del colágeno en los tejidos. A pesar de su disponibilidad en el ambiente y en diversos alimentos, la deficiencia de hierro en el cuerpo humano es común, pudiendo generar problemas de salud. La anemia ferropénica es una condición relacionada a una deficiencia de hierro, disminución en los niveles de hemoglobina y alteraciones en la morfología de las células encargadas de transportar oxígeno en nuestra sangre, los glóbulos rojos. Esta condición ocurre en todas las edades; sin embargo, su prevalencia es mayor en niños(as) menores de 2 años. Aunque puede inducirse por diversos factores, la anemia ferropénica se presenta en mayor medida en individuos con un estado nutricional de hierro insuficiente. Otras causas pueden ser la interacción del hierro con otros nutrientes, pérdidas o excreción y por requerimientos de crecimiento. A nivel mundial, es considerada un problema de salud pública, ya que conlleva a importantes implicaciones sobre la salud humana. Por lo que mantener los niveles adecuados de hierro en nuestro cuerpo a través de una dieta saludable es importante para nuestro crecimiento, salud y resistencia a enfermedades."

"Iron (Fe) is an abundant micromineral in our planet that participates in important biological processes, such as the transport of oxygen in the blood and the formation of collagen in the tissues. Despite its availability in the environment and a variety food items, iron deficiency in the human body is common and could lead to health issues. Iron-deficiency anemia is a condition related to iron deficiency, decrease in hemoglobin levels and alterations in the morphology of the cells responsable for transporting oxygen in our blood, the red blood cells. This condition occurs at all ages; however, its prevalence is higher in children under 2 years old. Although it can be induced by various factors, iron deficiency anemia occurs to a greater rate in individuals with an insufficient iron nutritional status. Other causes may be the interaction of iron with other nutrients, losses or excretion and growth requirements. Globally, it is considered a public health problem, as it has important implications on human health. Therefore, maintaining adequate levels of iron in our body through a healthy diet is important for our development, health, and resistance to diseases."

anemia ferropénica, hierro, nutrición, salud, reacción de Fenton MEDICINA Y CIENCIAS DE LA SALUD CIENCIAS MÉDICAS CIENCIAS DE LA NUTRICIÓN VITAMINAS VITAMINAS

Necessity as a driver in bending agricultural gender norms in the Eastern Gangetic Plains of South Asia

Pragya Timsina Emma Karki Brendan Brown (2023, [Artículo])

The majority of the farmers in the rural Global South continue to depend directly or indirectly on agriculture for their livelihoods. Despite the fact that women account for almost half of the world's farmers, they face gender-specific challenges such as deeply rooted cultural and social norms that limit their access to land, assets, financial markets, agricultural training, and information. Using semi-structured interviews with farmers in the Eastern Gangetic Plains, this study investigates how necessity is becoming one of the major drivers in the bending of agricultural gender norms. The study investigates the connections between feminist political ecology and agricultural technology production frameworks in order to comprehend the implications of technology adoption and influences on gender norms in communities. Women's participation in agriculture was found to be heavily influenced by social and cultural barriers, and they were frequently subjected to social criticism for breaking the systemic gender norms. This paper emphasizes on the growing pattern of bending gender norms with recommendations for increasing women's participation and scope in future agriculture development initiatives through policies and interventions that emphasize gender equity.

Social Barriers Cultural Barriers Feminist Political Ecology CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA GENDER NORMS WOMEN FARMERS AGRICULTURE TECHNOLOGY

High quality diet improves lipid metabolic profile and breeding performance in the blue-footed booby, a long-lived seabird

ERICK GONZALEZ MEDINA (2018, [Artículo])

Understanding the role of diet in the physiological condition of adults during reproduction and hence its effect on reproductive performance is fundamental to understand reproductive strategies in long-lived animals. In birds, little is known about the influence of the quality of food consumed at the beginning of the reproductive period and its short-term effects on reproductive performance. To assess the role of diet in the physiological condition of female blue-footed booby, Sula nebouxii (BFBO), during reproduction we evaluated whether individual differences in diet (assessed by using δ13C and δ15N values of whole blood from female birds and muscle tissue of the principal prey species) prior to egg laying and during incubation influenced their lipid metabolic profile (measured as triglyceride levels and C:N ratio) and their reproductive performance (defined by laying date, clutch size and hatching success). Females with higher δ15N values in their blood during the courtship and incubation periods had a higher lipid metabolic profile, earlier laying date, greater clutch size (2–3 eggs) and higher hatching success. Females that laid earlier and more eggs (2–3 eggs) consumed more Pacific anchoveta (Cetengraulis mysticetus) and Pacific thread herring (Opisthonema libertate) than did other females. These two prey species also had high amounts of lipids (C:N ratio) and caloric content (Kcal/g fresh weight). The quality of food consumed by females at the beginning of reproduction affected their physiological condition, as well as their short-term reproductive performance. Our work emphasizes the importance of determining the influence of food quality during reproduction to understand the reproductive decisions and consequences in long-lived animals. © 2018 González-Medina 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.

nitrogen 15, triacylglycerol, lipid, animal experiment, Article, breeding, carbon nitrogen ratio, clutch size, controlled study, courtship, diet, egg laying, female, food intake, hatching, lipid metabolism, muscle tissue, nonhuman, prey, reproduction CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA CIENCIAS DE LA TIERRA Y DEL ESPACIO OCEANOGRAFÍA OCEANOGRAFÍA

Vital and viable services for natural resources management in Latin America

JOSE LUIS MARTINEZ RUIZ RICARDO VICTOR LOPEZ MERA (2014, [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 Zonas urbanas Tecnología apropiada Informes de proyectos Xochimilco, Distrito Federal CIENCIAS SOCIALES

The Pacific harbor seal gut microbiota in Mexico: Its relationship with diet and functional inferences

ARLETTE MARIMAR PACHECO SANDOVAL (2019, [Artículo])

Diet is a primary driver of the composition of gut microbiota and is considered one of the main routes of microbial colonization. Prey identification is fundamental for correlating the diet with the presence of particular microbial groups. The present study examined how diet influenced the composition and function of the gut microbiota of the Pacific harbor seal (Phoca vitulina richardii) in order to better understand the role of prey consumption in shaping its microbiota. This species is a good indicator of the quality of the local environment due to both its foraging and haul-out site fidelity. DNA was extracted from 20 fecal samples collected from five harbor seal colonies located in Baja California, Mexico. The V4 region of 16S rRNA gene was amplified and sequenced using the Illumina technology. Results showed that the gut microbiota of the harbor seals was dominated by the phyla Firmicutes (37%), Bacteroidetes (26%) and Fusobacteria (26%) and revealed significant differences in its composition among the colonies. Funtional analysis using the PICRUSt software suggests a high number of pathways involved in the basal metabolism, such as those for carbohydrates (22%) and amino acids (20%), and those related to the degradation of persistent environmental pollutants. In addition, a DNA metabarcoding analysis of the same samples, via the amplification and sequencing of the mtRNA 16S and rRNA 18S genes, was used to identify the prey consumed by harbor seals revealing the consumption of prey with mainly demersal habits. Functional redundancy in the seal gut microbiota was observed, irrespective of diet or location. Our results indicate that the frequency of occurrence of specific prey in the harbor seal diet plays an important role in shaping the composition of the gut microbiota of harbor seals by influencing the relative abundance of specific groups of gut microorganisms. A significant relationship was found among diet, gut microbiota composition and OTUs assigned to a particular metabolic pathway. © 2019 Pacheco-Sandoval 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.

RNA 16S, RNA 18S, amino acid analysis, animal food, Article, bacterium colony, Bacteroidetes, basal metabolic rate, biodegradation, controlled study, DNA barcoding, feces analysis, Firmicutes, Fusobacteria, intestine flora, metabolism, Mexico, microb BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOLOGÍA ANIMAL (ZOOLOGÍA) BIOLOGÍA ANIMAL (ZOOLOGÍA)

Evaluación de indicadores de calidad y funcionalidad en islas de recursos, de mezquite (Prosopis articulata) y cardón (Pachycereus pringlei) en una zona restaurada de Baja California Sur

Geovanna Zárate Camargo (2024, [Tesis de maestría])

"Las temperaturas extremas, radiación solar intensa, vientos fuertes, humedad limitada y la baja fertilidad de los suelos desérticos dificultan la recuperación de zonas degradadas en zonas áridas. Uno de los fenómenos naturales más importantes de revegetación en zonas áridas son las islas de recursos, conformadas por algunos tipos de plantas que actúan como nodrizas, las cuales, bajo su dosel, desarrollan un microhábitat favorable para el establecimiento de otras especies que trabajan en conjunto con una larga comunidad de microorganismos que se encuentran en el suelo. Entre las plantas nodriza que se observan con más frecuencia en el Desierto de Sonora, se encuentran las especies del género Prosopis. Las islas de recursos conformadas por mezquites han demostrado tener un efecto positivo como planta nodriza en zonas áridas. Las contribuciones del mezquite son el aumento del contenido de N en el suelo, temperaturas moderadas en el suelo y la superficie, altos niveles de humedad, mayor actividad microbiana, entre otros aspectos que hacen posible los efectos de las islas de recursos. En este estudio se evaluaron diferentes indicadores de calidad de suelo en islas de recursos establecidas hace 19 años, como parte de un proyecto de revegetación de suelos degradados, distintivo del Desierto Sonorense. El objetivo de este estudio fue determinar si existe un gradiente con respecto a la distancia y profundidad, en la actividad microbiana y enzimática presente en suelos de islas de recursos, resultado de la interacción de mezquite amargo (Prosopis articulata), como planta nodriza y cardón (Pachycereus pringlei), como planta objetivo. Los resultados demostraron que existe un aumento la actividad enzimática y carbono asociado a biomasa microbiana del suelo perteneciente a estas islas, con mayores resultados en zonas próximas a la planta nodriza que en zonas sin su influencia, también se encontró un aumento en la capa superficial del suelo mostrando mayores valores en los indicadores de calidad y funcionalidad bajo el dosel de las islas de recursos. Lo anterior sugiere que el uso de estas islas de recursos es una potencial alternativa en la restauración de suelos degradados, favoreciendo el ciclaje de nutrientes en suelos degradados."

"At desert, the high temperatures, intense solar radiation, strong winds, limited water, and low fertility, determine how challenging will be the recovery of degraded soils in arid lands. One of the most important natural phenomena of revegetation in arid lands are the “resource islands”, that consist of some trees or bushes acting as nurse plants, which under their canopy, develop a beneficial microhabitat for the establishment of other plant species the work with an extensive community of microorganisms found in the soil. Among the most common nurse plants observed in the Sonoran Desert, is the genus Prosopis. The resource islands formed with mesquite have shown positive effects as nurse plant in arid lands. The principal contributions of mesquite are the increase of N in the soil, moderate temperatures on soil and topsoil, high moisture levels, increased microbial activity, among other aspects that make possible the effect of resource islands. In this study, different quality indicators were evaluated in resource islands established 19 years ago, as part of a project for revegetation in degraded soils, distinctive from the Sonoran Desert. The aim of this research was to explore whether there is a correlation between distance, depth, microbial activity, and enzymatic activity in the soil surrounding resource islands formed by the interaction between mesquite amargo (Prosopis articulata) as the nurse plant and cardon (Pachycereus pringlei) as the objective plant. The results demonstrated that there is an increase in the enzymatic activity and microbial biomass carbon from the soil under the canopy of the resource islands, with higher results in zones near the nurse plant than zones without its influence, furthermore, there was found an increase in the topsoil showing higher values in the soil quality and functionality indicators under the canopy of the resource islands. The above indicates that the use of these resource islands is a potential alternative in the degraded soil restoration, supporting the nutrient cycling in degraded soils."

suelo, ecología, revegetación, actividad enzimática, ciclaje de nutrientes soil, ecology, revegetation, enzymatic activity, nutrient cycling CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CIENCIAS AGRARIAS AGRONOMÍA FERTILIDAD DEL SUELO FERTILIDAD DEL SUELO

Stability of FeVO4-II under Pressure: A First-Principles Study

PRICILA BETBIRAI ROMERO VAZQUEZ SINHUE LOPEZ MORENO Daniel Errandonea (2022, [Artículo])

"In this work, we report first-principles calculations to study FeVO4 in the CrVO4-type (phase II) structure under pressure. Total-energy calculations were performed in order to analyze the structural parameters, the electronic, elastic, mechanical, and vibrational properties of FeVO4-II up to 9.6 GPa for the first time. We found a good agreement in the structural parameters with the experimental results available in the literature. The electronic structure analysis was complemented with results obtained from the Laplacian of the charge density at the bond critical points within the Quantum Theory of Atoms in Molecules methodology. Our findings from the elastic, mechanic, and vibrational properties were correlated to determine the elastic and dynamic stability of FeVO4-II under pressure. Calculations suggest that beyond the maximum pressure covered by our study, this phase could undergo a phase transition to a wolframite-type structure, such as in CrVO4 and InVO4."

FeVO4 under pressure CrVO4-type structure First-principles Mechanical properties Vibrational properties Electronic properties CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA FÍSICA DEL ESTADO SÓLIDO CRISTALOGRAFÍA CRISTALOGRAFÍA

Appraisal of complementarity of subsurface drip fertigation and conservation agriculture for physiological performance and water economy of maize

C.M. Parihar Hari Sankar Nayak Dipaka Ranjan Sena Renu Pandey Mahesh Gathala ML JAT (2023, [Artículo])

The Indo-Gangetic Plains (IGP) in north-west (NW) India are facing a severe decline in ground water due to prevalent rice-based cropping systems. To combat this issue, conservation agriculture (CA) with an alternative crop/s, such as maize, is being promoted. Recently, surface drip fertigation has also been evaluated as a viable option to address low-nutrient use efficiency and water scarcity problems for cereals. While the individual benefits of CA and sub-surface drip (SSD) irrigation on water economy are well-established, information regarding their combined effect in cereal-based systems is lacking. Therefore, we conducted a two-year field experiment in maize, under an ongoing CA-based maize-wheat system, to evaluate the complementarity of CA with SSD irrigation through two technological interventions–– CA+ (residue retained CA + SSD), PCA+ (partial CA without residue + SSD) – at different N rates (0, 120 and 150 kg N ha-1) in comparison to traditional furrow irrigated (FI) CA and conventional tillage (CT) at 120 kg N ha-1. Our results showed that CA+ had the highest grain yield (8.2 t ha-1), followed by PCA+ (8.1 t ha-1). The grain yield under CA+ at 150 kg N ha-1 was 27% and 30% higher than CA and CT, respectively. Even at the same N level (120 kg N ha-1), CA+ outperformed CA and CT by 16% and 18%, respectively. The physiological performance of maize also revealed that CA+ based plots with 120 kg N ha-1 had 12% and 3% higher photosynthesis rate at knee-high and silking, respectively compared to FI-CA and CT. Overall, compared to the FI-CA and CT, SSD-based CA+ and PCA+ saved 54% irrigation water and increased water productivity (WP) by more than twice. Similarly, a greater number of split N application through fertigation in PCA+ and CA+ increased agronomic nitrogen use efficiency (NUE) and recover efficiency by 8–19% and 14–25%, respectively. Net returns from PCA+ and CA+ at 150 kg N ha-1 were significantly higher by US$ 491 and 456, respectively than the FI-CA and CT treatments. Therefore, CA coupled with SSD provided tangible benefits in terms of yield, irrigation water saving, WP, NUE and profitability. Efforts should be directed towards increasing farmers’ awareness of the benefits of such promising technology for the cultivating food grains and commercial crops such as maize. Concurrently, government support and strict policies are required to enhance the system adaptability.

Net Returns Subsurface Drip Irrigation Subsurface Drip Fertigation CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA EFFICIENCY GRAIN NITROGEN PHOTOSYNTHESIS PHYSIOLOGY WATER SUPPLY CONSERVATION AGRICULTURE CONVENTIONAL TILLAGE FERTIGATION GROUNDWATER NITROGEN-USE EFFICIENCY WATER PRODUCTIVITY

Trophic ecology of Mexican Pacific harbor seal colonies using carbon and nitrogen stable isotopes

MARICELA JUAREZ RODRIGUEZ (2020, [Artículo])

There is limited information that provides a comprehensive understanding of the trophic ecology of Mexican Pacific harbor seal (Phoca vitulina richardii) colonies. While scat analysis has been used to determine the diet of some colonies, the integrative characterization of its feeding habits on broader temporal and spatial scales remains limited. We examined potential feeding grounds, trophic niche width, and overlap, and inferred the degree of dietary specialization using stable carbon and nitrogen isotope ratios (δ13C and δ15N) in this subspecies. We analyzed δ13C and δ15N on fur samples from pups collected at five sites along the western coast of the Baja California Peninsula, Mexico. Fur of natal coat of Pacific harbor seal pups begins to grow during the seventh month in utero until the last stage of gestation. Therefore pup fur is a good proxy for the mother's feeding habits in winter (∼December to March), based on the timing of gestation for the subspecies in this region. Our results indicated that the δ13C and δ15N values differed significantly among sampling sites, with the highest mean δ15N value occurring at the southernmost site, reflecting a well-characterized north to south latitudinal 15N-enrichment in the food web. The tendency identified in δ13C values, in which the northern colonies showed the most enriched values, suggests nearshore and benthic-demersal feeding habits. A low variance in δ13C and δ15N values for each colony (<1‰) and relatively small standard ellipse areas suggest a specialized foraging behavior in adult female Pacific harbor seals in Mexican waters. © 2020 Juárez-Rodríguez et al.

carbon, delta carbon 13, delta nitrogen 15, isotope, nitrogen, unclassified drug, carbon, nitrogen, Article, correlational study, feeding behavior, latitude, Mexico, nonhuman, organism colony, Pinnipedia, population abundance, species richness, troph BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOLOGÍA ANIMAL (ZOOLOGÍA) BIOLOGÍA ANIMAL (ZOOLOGÍA)

Sitios Ramsar de la Bahía de La Paz: Amenazas y estrategias para su conservación

Ramsar Sites of La Paz Bay: Threats and strategies for their conservation

Janette Magalli Murillo Jiménez José Juan Pérez Navarro María Concepción Lora Vilchis MARIA DEL ROCIO MARCIN MEDINA LAURA CARREON PALAU Jorge A. Del Angel_Rodríguez Jose Luis Ortiz Galindo Jesús Echevarría Haro (2022, [Artículo])

"En 2017–2018 la Secretaría de Marina del Gobierno de México (SEMAR) realizó actividades de dragado en la Bahía y Ensenada de La Paz, Baja California Sur. Paralelamente ocurrieron afectaciones severas en el sitio Ramsar “Humedales Mogote-Ensenada de La Paz”. Los dragados y el mal manejo de los residuos generaron preocupación ciudadana por el sitio y los organismos que ahí habitan, lo que se manifestó en protestas tanto mediáticas, como legales ante SEMARNAT por algunas organizaciones de la sociedad civil. Esta situación propició la organización de un Foro-Taller realizado el 3 de octubre de 2019, con el fin de evaluar la problemática de los humedales tanto de la Ensenada como de la Bahía de La Paz, ambos incluidos en la Convención Ramsar. El presente trabajo resume los resultados de este evento y refleja la gran preocupación por los sitios Ramsar, tanto de la sociedad civil, como de las diferentes instancias gubernamentales. Estos resultados se integraron en un documento entregado en febrero de 2020 solo a autoridades de SEMARNAT, CONANP y Congreso del Estado de Baja California Sur, previo a la pandemia. Durante el taller se observó una amplia gama de problemas, originados en gran medida por los habitantes y reforzados por el incumplimiento de los compromisos adquiridos por México ante la Convención Ramsar, patente en la desatención de los sitios Ramsar, en particular de los Humedales Mogote-Ensenada de La Paz, donde no hay una normatividad específica que indique la responsabilidad de la gestión de estos ecosistemas. En contraste, el humedal de Balandra cuenta con protección especial al formar parte de una ANP. La conclusión general más importante del evento fue que sólo una sociedad bien organizada, informada de los servicios ambientales que estos sitios proveen, y consciente de su valor como ecosistemas, podrá defender la sustentabilidad de estos sitios."

"In 2017–2018, the Government of Mexico’s Navy Secretariat (SEMAR) carried out dredging activities in Bahía and Ensenada de La Paz, Baja California Sur. In parallel there were severe impacts on the Ramsar site “Humedales Mogote-Ensenada de La Paz”. The dredging and the mis management of the waste generated citizen concern for the site and their inhabiting organisms. Consequently, there were protests that were prosecuted both in the media and legally before SEMARNAT by some non-governmental organizations (ONGs). On October 3, 2019, indignation led to the organization of a Forum-Workshop to assess the problem of wetlands in Bahía and Ensenada de La Paz, included in the Ramsar Convention. Here we present a summary of the Workshop results that reflect the great concern for Ramsar sites, both from civil society, and from different government entities. The results were integrated into a document delivered in February 2020 only to the authorities of SEMARNAT, CONANP and to the Baja California Sur State Congress, because the advent of the Covid-19 pandemic prevented the delivery to all other institutions involved, identified as responsible in the Workshop. Participants observed a wide range of problems in these sites originated largely by residents and reinforced by non-compliance with commitments acquired by Mexico towards the Ramsar Convention, evident in the neglect of the Ramsar sites, in particular the Mogote-Ensenada de La Paz wetlands, where no specific regulation indicates the responsibility of the management of these ecosystems. In contrast, it was observed that the wetland of Balandra has special protection by being part of a Natural Protected Area (ANP, by its acronym in Spanish). The most important general conclusion of this event was that only a we- ll-organized society, informed of the environmental services that these sites provide, and aware of their value as ecosystems, will be able to defend the sustainability of these sites."

Gestión participativa, Dragados, Conservación humedales, Servicios Ecosistémicos, Mortandad delfines CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CIENCIAS AGRARIAS CIENCIA FORESTAL CONSERVACIÓN CONSERVACIÓN