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Risk aversion, impatience, and adoption of conservation agriculture practices among smallholders in Zambia

Hambulo Ngoma João Vasco Silva Frédéric Baudron Isaiah Nyagumbo Christian Thierfelder (2024, [Artículo])

Sustainable agricultural practices such as conservation agriculture have been promoted in southern Africa for nearly three decades, but their adoption remains low. It is of policy interest to unpack behavioural drivers of adoption to understand why adoption remains lower than anticipated. This paper assesses the effects of risk aversion and impatience on the extent and intensity of the adoption of conservation agriculture using panel data collected from 646 households in 2021 and 2022 in Zambia. We find that 12% and 18% of the smallholders were impatient and risk averse, respectively. There are two main empirical findings based on panel data Probit and Tobit models. First, on the extensive margin, being impatient is correlated with a decreased likelihood of adopting combined minimum-tillage (MT) and rotation by 2.9 percentage points and being risk averse is associated with a decreased propensity of adopting combined minimum tillage (MT) and mulching by 3.2 percentage points. Being risk averse is correlated with a decreased chance of adopting basins by 2.8 percentage points. Second, on the intensive margin, impatience and risk aversion are significantly correlated with reduced adoption intensity of basins, ripping, minimum tillage (MT), and combined MT and rotation by 0.02–0.22 ha. These findings imply a need to embed risk management (e.g., through crop yield insurance) in the scaling of sustainable agricultural practices to incentivise adoption. This can help to nudge initial adoption and to protect farmers from yield penalties that are common in experimentation stages.

Risk and Time Preferences CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA TECHNOLOGY ADOPTION RISK SUSTAINABLE INTENSIFICATION SMALLHOLDERS

Sustainable maize intensification through site-specific nutrient management advice: Experimental evidence from Nigeria

Miet Maertens Oyakhilomen Oyinbo Tahirou Abdoulaye Jordan Chamberlin (2023, [Artículo])

There is growing evidence on the impacts of site-specific nutrient management (SSNM) from Asia. The evidence for Sub-Saharan Africa (SSA), where SSNM developments are more recent and where conditions concerning soil fertility and fertilizer use differ importantly from those in Asia, is extremely scarce. We evaluate a SSNM advisory tool that allows extension agents to generate fertilizer recommendations tailored to the specific situation of an individual farmer’s field, using a three-year randomized controlled trial with 792 smallholder farmers in the maize belt of northern Nigeria. Two treatment arms were implemented: T1 and T2 both provide SSNM information on nutrient use and management, but T2 provides additional information on maize price distributions and the associated variability of expected returns to fertilizer use. We estimate average and heterogenous intent-to-treat effects on agronomic, economic and environmental plot-level outcomes. We find that T1 and T2 lead to substantial increases (up to 116%) in the adoption of good fertilizer management practices and T2 leads to incremental increases (up to 18%) in nutrient application rates, yields and revenues. Both treatments improve low levels of nutrient use efficiency and reduce high levels of greenhouse gas emission intensity, after two years of treatment. Our findings underscore the possibility of a more gradual and sustainable intensification of smallholder agriculture in SSA, as compared with the Asian Green Revolution, through increased fertilizer use accompanied by improved fertilizer management.

Randomized Controlled Trial CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA TECHNOLOGY ADOPTION AGRICULTURAL EXTENSION GREEN REVOLUTION FERTILIZERS GREENHOUSE GAS EMISSIONS

Socio-technological responses to COVID-19 in Mexico: Spin-offs, repositories and 3D printing

Max Matus (2023, [Artículo, Artículo])

The objective of the article is to analyze two sociotechnical initiatives, one citizen and the other governmental, that were configured in Mexico as a response to the shortage and hoarding of medical devices in the context of the COVID-19 pandemic. The citizen response analyzed is the coronavirus_maker_mx movement, while the governmental initiative under scrutiny are the Gätsy and Ehecátl 4T ventilators developed under the coordination of the National Council on Science and Technology. The methodology used involved online tracking of coronavirus_maker groups, open interviews with community members, and review of second-hand sources in the case of the government initiative. By unraveling the networks of actors that were behind the design and production or printing of devices to address COVID-19, we conclude that the cases analyzed represent different models of technological development that invite us to think about some alternatives for the promotion of "sovereign" technology in Mexico.

Impresión 3D manufactura aditiva makers ciencia abierta CIENCIAS SOCIALES CIENCIAS SOCIALES 3D printing additive manufacture open science

Evaluación de un derivado de la Adenosina sobre la metástasis ósea inducida por el cáncer de mama

Evaluation of an Adenosine derivative on breast cancer induced bone metastasesEvaluation of an Adenosine derivative on breast cancer induced bone metastases

Citlalli Oyuki Mendoza Chacón (2024, [Tesis de maestría])

El cáncer de mama (CM) es considerado como el tipo de cáncer con mayor incidencia y la principal causa de muerte en mujeres en el mundo. Cuando el cáncer está avanzado y ha migrado a otros órganos y específicamente a los huesos, se conoce como metástasis ósea. Los tratamientos actuales ofrecen a los pacientes un panorama favorable cuando el cáncer está en estadio temprano; sin embargo, aún no existe una terapia que cure la metástasis ósea. La adenosina y sus derivados han demostrado su potencial en la regulación del crecimiento tumoral y la supervivencia de las células cancerosas. Por lo tanto, este trabajo tuvo como objetivo evaluar el potencial anticancerígeno de un derivado de la adenosina (IFC 305) sobre células de cáncer de mama 4T1 in vitro mediante ensayos de proliferación, migración, ciclo celular y apoptosis; así mismo, su efecto en un modelo in vivo de metástasis ósea. Los datos demuestran que el fármaco IFC 305 disminuye la proliferación y migración de la línea celular 4T1 dependiendo de la concentración utilizada. Por otro lado, no induce apoptosis a las 24 horas de tratamiento, pero sí un arresto del ciclo celular en la fase G0/G1. Sin embargo, el tratamiento con IFC 305 de ratones con metástasis ósea, no tuvo efecto en la disminución de las lesiones osteolíticas. Estudios futuros son necesarios para optimizar la dosis y tratamiento necesario para el modelo in vivo. En conclusión, nuestro trabajo demostró el potencial anticancerígeno del IFC 305 en ensayos in vitro, a través de la inhibición del crecimiento celular y la migración de las células cancerígenas, y sienta las bases para futuros estudios in vivo que demuestren su potencial terapéutico para el tratamiento de la metástasis ósea causada por el cáncer de mama.

Breast cancer is the type of cancer with the highest incidence and the leading cause of death in women due to this condition. When cancer cells migrate to other organs, especially bones, it is known as bone metastasis. Although the prognosis for some patients may be favorable due to early detection and treatment, there is still no therapy to cure bone metastasis by breast cancer. Adenosine and its derivatives have demonstrated their relevance in controlling proliferation, immune response, and apoptosis in different types of cancer. In this project, the anticancer potential of the drug IFC 305, a derivative of adenosine, on bone metastasis induced by breast cancer was evaluated both in vitro and in vivo. To evaluate the effect of IFC 305 on cell proliferation and migration of the 4T1 murine breast cancer cell line, the MTT assay and wound healing assay were used, respectively. The drug inhibited the proliferation and migration of 4T1 cells in a dose-dependent manner. To understand the underlying mechanism, apoptosis and the cell cycle were analyzed by flow cytometry. Results showed that after 24 hours of exposure to the drug, the effect on apoptosis is minimal. However, it was found that 4T1 cells were arrested in the G0/G1 phase of the cell cycle. However, IFC 305 treatment of mice with bone metastasis did not reduce osteolytic lesions. Future studies are necessary to optimize the dose and treatment necessary for the in vivo model. In conclusion, our work demonstrates the anticancer potential of IFC 305 on in vitro assays, through the inhibition of cell growth and migration of cancer cells. These studies seed the bases for future in vivo studies that demonstrate the IFC 305 therapeutic potential for the treatment of bone metastasis caused by breast cancer.

cáncer de mama, tratamientos, derivado de adenosina, metástasis Breast cancer, treatments, adenosine derivate, metastasis BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOLOGÍA CELULAR OTRAS OTRAS

Studies of plant hydraulics and water relations in mexican environments: adaptation, physiology, and applications

Estudios sobre hidráulica y relaciones hídricas de plantas en ambientes mexicanos: adaptaciones, fisiología y aplicaciones

RODRIGO MENDEZ ALONZO Mark Olson Horacio Paz Casandra Reyes García CELENE MARISOL ESPADAS MANRIQUE CLARA TINOCO OJANGUREN Santiago Trueba (2022, [Artículo])

Given the outstanding global progress of research on the hydraulic pathway in plants, and its important role as an indicator of plant mortality risk, we reviewed: (1) the adaptive basis of hydraulic traits and their importance for overall plant function; (2) the number of primary scientific articles on plant hydraulics that have been produced in Mexico in the last 40 years, (3) research related to specific environments in Mexico, and (4) the possible applications of plant hydraulics to natural resource management. Our systematic review included 83 articles. The number of publications per year steadily increased over time, reaching its maximum in 2021. Veracruz and Yucatán are the states where the majority of scientific articles on plant hydraulics have been produced, but for most states less than two publications on this subject appeared in ca. 40 years, and none was found for Oaxaca and Chiapas, the most biodiverse states. In plant hydraulics, the most studied biome in Mexico was the tropical dry forest, followed by crops; trees were the most studied growth-form, followed by herbaceous crops and epiphytes. We point to the need of enhancing research in the interface between plant hydraulic function and remote sensing, as well as developing applications in adaptive forest management and ecological restoration. We hope that this review may ignite a national collaborative effort to quantify critical traits that could inform the hydraulic functioning of Mexican ecosystems, particularly in the underrepresented and highly diverse states of Mexico. © 2022 Sociedad Botanica de Mexico, A.C. All rights reserved.

ADAPTATION DROUGHT VULNERABILITY ECOPHYSIOLOGY PLANT WATER RELATIONS SYSTEMATIC REVIEW BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOLOGÍA VEGETAL (BOTÁNICA) ECOLOGÍA VEGETAL ECOLOGÍA VEGETAL