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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

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

Diseño de una red de dispositivos inalámbricos para monitorear la calidad del aire en interiores

FRIDA JENNY DE LA ROSA ANDRADE (2023, [Tesis de maestría])

No cabe duda de que la contaminación ambiental siempre a existido, y es una consecuencia

producida por las diferentes actividades que el ser humano ha realizado a lo largo de su

desarrollo y evolución tecnológica, por lo que conlleva a muchas repercusiones en la

integridad física del ambiente. Las actividades de desarrollo, como la construcción, el

transporte y la fabricación, no solo agotan los recursos naturales, sino que también producen

una gran cantidad de desechos que conducen a la contaminación del aire, el agua, el suelo y

los océanos, dando pie a los problemas más preocupantes del ser humano, tal es el caso del

calentamiento global, las lluvias acidas. Hoy en día la contaminación del aire se considera

un tema de gran importancia puesto que, es uno de los principales problemas en las zonas

más urbanizadas del mundo, y se encuentra presente tanto en los países desarrollados como

en los no desarrollados, por ello surge la necesidad de conocer que tan contaminado se

encuentra el aire que se respira.

El estándar de calidad del aire es una táctica para establecer las condiciones del aire desde un

grado de pureza, hasta una calidad critica perjudicial para el deterioro de la salud humana,

haciendo referencia a la cantidad de contaminación presente en el aire, definiéndola ya sea

de alta calidad con un nivel bajo de contaminación o una mala calidad con un nivel elevado

de concentración de contaminación en el aire.

En este proyecto se diseñará una Red de dispositivos inalámbricos para el análisis y

monitoreo de la calidad del aire en interiores, con la finalidad de fungir como un medidor de

contaminación que le permita a las personas darse cuenta de que tan contaminados están sus

hogares. Por tal motivo en el desarrollo de este proyecto se hará uso de un microcontrolador

Arduino IDE, un Node-red y un phpMyadmin para el análisis y monotoreo constante de

diversos gases como CO, CO2, metano, nitrógeno y O2. Cabe mencionar que este escrito se

ha dividido en 4 capítulos en los cuales se explica detalladamente todos y cada uno de los

procesos llevado a cabo para la elaboración y el desarrollo de este proyecto.

There is no doubt that environmental pollution has always existed, and is a consequence

produced by the different activities that human beings have carried out throughout their

development and technological evolution, which leads to many repercussions on the physical

integrity of the environment. Development activities such as construction, transportation and

manufacturing not only deplete natural resources but also produce a large amount of waste

leading to pollution of air, water, soil and oceans, giving rise to to the most worrying problems

of human beings, such as global warming and acid rain. Nowadays, air pollution is considered

an issue of great importance since it is one of the main problems in the most urbanized areas

of the world, and is present in both developed and undeveloped countries, which is why the

need to know how contaminated the air you breathe is.

The air quality standard is a tactic to establish air conditions from a degree of purity to a

critical quality harmful to the deterioration of human health, referring to the amount of

pollution present in the air, defining it either high quality with a low level of contamination

or poor quality with a high level of concentration of contamination in the air.

In this project, a network of wireless devices will be designed for the analysis and monitoring

of indoor air quality, with the purpose of serving as a pollution meter that allows people to

realize how polluted their homes are. For this reason, in the development of this project, an

Arduino IDE microcontroller, a Node-red and a phpMyadmin will be used for the analysis

and constant monitoring of various gases such as CO, CO2, methane, nitrogen and O2. It is

worth mentioning that this writing has been divided into 4 chapters in which each and every

one of the processes carried out for the preparation and development of this project is

explained in detail.

BIOLOGÍA Y QUÍMICA QUÍMICA Red de dispositivos inalámbricos, análisis monitoreo, calidad, riesgo, contaminación. Network of wireless devices, monitoring analysis, quality, risk, contamination.

Fabricación de nanopartículas de oro dentro de óxido de aluminio (γ-Al2O3) nanoestructurado con cavidades esféricas

Manufacturing of Gold Nanoparticles within Nanostructured Aluminum Oxide (γ-Al2O3) with Spherical Cavities

Mariela de Jesús Franco Gallegos (2023, [Tesis de maestría])

Los catalizadores basados en nanopartículas de oro han generado gran interés, gracias a su capacidad de ser selectivos en la promoción de reacciones específicas o en la producción de productos deseados, minimizando la formación de productos secundarios no deseados; sus propiedades electrónicas únicas; y su utilización bajo condiciones ambientales. Sin embargo, la desventaja principal de los catalizadores de oro es la sinterización de las nanopartículas debido a su baja temperatura de fusión, lo que provoca la pérdida de actividad catalítica y la desactivación del catalizador. Una de lassoluciones que ofrece el uso de la nanociencia y la nanotecnología es la utilización de soportes nanoestructurados que den mejor estabilidad a las nanopartículas y las protejan de la desactivación. En este trabajo se sintetizaron catalizadores basados en nanopartículas de oro soportados y encapsulados en alúmina macroporosa, por un método de impregnación húmeda asistida por ultrasonido; un método sencillo, rápido y ecológico. El desempeño catalítico de materiales sintetizados se analizó mediante espectroscopía UV-Visible in-situ en la reducción de 4-Nitrofenol a 4-Aminofenol. Así mismo, se presentan las caracterizaciones por TEM, SEM, FT-IR, espectroscopía UV-Visible, y XRD de catalizadores obtenidos. Se obtuvieron catalizadores altamente activos con alto rendimiento gracias al uso de un soporte nanoestructurado.

Catalysts -based on gold nanoparticles have recently gained interest due to their ability to selectively promote specific catalytic reactions or produce desired products, while minimizing the formation of unwanted byproducts, their unique electronic properties, and their utilization under ambient conditions. However, the main drawback of gold catalysts is the sintering of nanoparticles due to their low melting temperature, which leads to loss of catalytic activity and catalyst deactivation. One of the solutions offered by nanoscience and nanotechnology is the use of nanostructured supports that provide better stability to the nanoparticles and protect them from deactivation. In this work, gold nanoparticle-based catalysts supported and encapsulated in macroporous alumina were synthesized using a simple, fast, and eco-friendly method of ultrasound-assisted wet impregnation. The catalytic performance of synthetized materials was evaluated by in-situ UV-Visible spectroscopy in the reduction of 4-Nitrophenol to 4-Aminophenol. In addition, their characterization by TEM, SEM, FT-IR, UV Visible spectroscopy and XRD are presented. Highly active catalysts with high performance were obtained thanks to the use of a nanostructured supports.

nanopartículas de oro, alúmina macroporosa, impregnación, reducción 4-NF gold nanoparticles, macroporous alumina, impregnation, 4-NF reduction INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS TECNOLOGÍA DE MATERIALES PROPIEDADES DE LOS MATERIALES PROPIEDADES DE LOS MATERIALES