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Seed integrity, effect of temperature and storage time on germination of Populus luziarum and P. primaveralepensis, endangered subtropical species from Mexico

César Jacobo Pereira MIGUEL ANGEL MUÑIZ CASTRO JOSE ANTONIO VAZQUEZ GARCIA Joel David Flores Rivas ALEJANDRO MUÑOZ URIAS FRANCISCO MARTIN HUERTA MARTINEZ (2022, [Artículo])

"Background: Populus luziarum and P. primaveralepensis are endemic species of western Mexico; growing in riparian forests they are critically endangered. The best way to conserve their seeds is unknown, which could be limiting for their conservation.

Hypothesis: The germinability of both subtropical species is like that of boreal and template Salicaceae species that disperse seeds in spring and early summer, as they germinate quickly with high percentages, and rapidly lose their viability when stored at ambient temperature.

Studied species: Populus luziarum and P. primaveralepensis. Study site and dates: Western Trans-Mexican Volcanic Belt. Jalisco, Mexico. October 2019.

Methods: The physical integrity of the seeds was assessed by X-ray imaging and compared with germinability. In addition, the effect of storage time (nine weeks) under two temperatures (4 and 21 °C) on the percentage and mean germination rate was evaluated.

Results: No significant differences were found between physical integrity and germination in freshly collected seeds for both species. Germination in the first 24 hrs was 91 and 95 % for Populus luziarum and P. primaveralepensis, respectively (week 0). Germination percentages were lower when stored at 21 °C, but P. primaveralepensis was decreased more slowly.

Conclusions: Seeds of subtropical Populus respond similarly to those of species from temperate and boreal climates with early seed dispersal, a crucial condition for establishing ex situ reforestation and conservation programs."

Salicaceae Seed physical integrity Seed storage conditions Subtropical endemic species White poplars BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOLOGÍA VEGETAL (BOTÁNICA) BIOLOGÍA VEGETAL (BOTÁNICA)

Risk, Covid-19 and hospital care in Mexico City: Are we moving toward a new medical practice?

Rubén Muñoz (2023, [Artículo, Artículo])

Covid-19 pandemic has entailed new challenges for health care in the Mexican public health sector, producing changes in clinical practices that are now handling patients infected with covid-19 and also outpatient consultations at tertiary-level care hospitals. Some of these challenges are related to the perception of risk held by physicians regarding the possibility of contracting or transmitting covid-19 during their work,and to the management of risk from the standpoint of biomedical organizational culture linked to the material and symbolic conditions of public health services predating the pandemic. We analyze these issues from a anthropological research based on in-depth interviews to physicians that work with covid-19 patients at “Covid-19 hospitals” or “hybrid hospitals” in Mexico City. Covid-19 has arrived in social relations and perceptions of risk in the arena of health care and involves knowing and transforming some structural and symbolic conditions, resignified with the pandemic, for proper medical care.

Covid-19 percepción de riesgo personal de salud atención médica hospitalaria cultura organizacional biomédica CIENCIAS SOCIALES CIENCIAS SOCIALES risk perception health care workers hospital care biomedical organizational culture

Farmers’ perspectives as determinants for adoption of conservation agriculture practices in Indo-Gangetic Plains of India

Ajay Kumar Mishra ML JAT (2022, [Artículo])

Understanding the farmer's perspective has traditionally been critical to influencing the adoption and out-scaling of CA-based climate-resilient practices. The objective of this study was to investigate the biophysical, socio-economic, and technical constraints in the adoption of CA by farmers in the Western- and Eastern-IGP, i.e., Karnal, Haryana, and Samastipur, Bihar, respectively. A pre-tested structured questionnaire was administered to 50 households practicing CA in Western- and Eastern-IGP. Smallholder farmers (<2 ha of landholding) in Karnal are 10% and Samastipur 66%. About 46% and 8% of households test soil periodically in Karnal and Samastipur, respectively. Results of PCA suggest economic profitability and soil health as core components from the farmer's motivational perspective in Karnal and Samastipur, respectively. Promotion and scaling up of CA technologies should be targeted per site-specific requirements, emphasizing biophysical resource availability, socio-economic constraints, and future impacts of such technology.

Smallholder Farmers Agents of Change Technology Diffusion Climate-Smart Practices CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA SMALLHOLDERS SOCIAL STRUCTURE IRRIGATION MANAGEMENT TECHNOLOGY CLIMATE-SMART AGRICULTURE CONSERVATION AGRICULTURE

Caracterización de fuentes puntuales de contaminación en el rio Atoyac, México

María del Pilar Saldaña Fabela María Antonieta Gómez Balandra (2006, [Artículo])

Es claro que los problemas de contaminación en los cuerpos de agua, se deben principalmente a las descargas puntuales que son vertidas sin previo tratamiento, y a las que pasan por algún proceso de tratamiento remueven ligeramente los contaminantes, debido a una baja eficiencia de remoción, o bien a que el sistema de tratamiento no es el adecuado para el tipo de compuestos que se descargan. En México la normatividad establece que las descargas deben de cumplir con los parámetros de la NOM-001-SEMARNAT-1996, la cual enlista a ocho básicos, nueve metales pesados y un microbiológico. El objetivo del estudio fue el determinar la calidad del agua de las fuentes puntuales de contaminación que son aportadas al río Atoyac, Puebla y su cumplimiento con la normatividad vigente. Se realizaron muestreos de las descargas industriales para identificar aquellos parámetros que sobrepasaron la norma, asimismo, se incluyo el análisis de toxicidad con Vibrio fischery para evaluar la mezcla de contaminantes de la descarga y contar con información de en parámetro que integra los probables efectos adversos que se presenten en cuerpo receptor.

Ríos Fuentes puntuales de contaminación Río Atoyac BIOLOGÍA Y QUÍMICA