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Distance learning for farmers: Experience during the pandemic

Andrea Gardeazabal (2023, [Documento de trabajo])

In response to the COVID-19 pandemic's disruption of farmer training—a crucial component for enhancing the resilience and livelihoods of smallholder farmers—CIMMYT innovated educational solutions to sustain capacity building in agri-food systems. Addressing the challenges of limited mobile device access, poor internet connectivity, and digital illiteracy, CIMMYT implemented two pilot projects in Mexico. These projects facilitated distance learning for adult farmers in rural areas, employing both internet-based and non-internet methods. The non-internet approach utilized traditional media like print, while the internet-based approach leveraged WhatsApp for educational content delivery. Building on these experiences, CIMMYT expanded its offerings by creating micro -courses delivered through WhatsApp, hosted on the Co-LAB's new Learning Network platform, specifically targeting farmers. This paper delves into the various strategies, methods, and techniques adopted, documenting the learning outcomes, results, and key conclusions drawn from these innovative training initiatives.

Distance Learning Digital Inclusion Innovative Training CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA DISTANCE EDUCATION CAPACITY DEVELOPMENT METHODS COMMUNICATION TECHNOLOGY

Environmental Nanoparticles Reach Human Fetal Brains

LILIAN OFELIA CALDERON GARCIDUEÑAS ANGEL AUGUSTO PEREZ CALATAYUD ANGELICA GONZALEZ MACIEL RAFAEL REYNOSO ROBLES Héctor Gabriel Silva Pereyra Andrea Ramos Morales RICARDO TORRES JARDON Candelario de Jesús Soberanes Cerino Raúl Carrillo Esper JESÚS CARLOS BRIONES GARDUÑO Yazmin del Socorro Conde Gutiérrez (2022, [Artículo])

"Anthropogenic ultrafine particulate matter (UFPM) and industrial and natural nanoparticles (NPs) are ubiquitous. Normal term, preeclamptic, and postconceptional weeks(PCW) 8–15 human placentas and brains from polluted Mexican cities were analyzed by TEM and energy-dispersive X-ray spectroscopy. We documented NPs in maternal erythrocytes, early syncytiotrophoblast, Hofbauer cells, and fetal endothelium (ECs). Fetal ECs exhibited caveolar NP activity and widespread erythroblast contact. Brain ECs displayed micropodial extensions reaching luminal NP-loaded erythroblasts. Neurons and primitive glia displayed nuclear, organelle, and cytoplasmic NPs in both singles and conglomerates. Nanoscale Fe, Ti, and Al alloys, Hg, Cu, Ca, Sn, and Si were detected in placentas and fetal brains. Preeclamptic fetal blood NP vesicles are prospective neonate UFPM exposure biomarkers. NPs are reaching brain tissues at the early developmental PCW 8–15 stage, and NPs in maternal and fetal placental tissue compartments strongly suggests the placental barrier is not limiting the access of environmental NPs. Erythroblasts are the main early NP carriers to fetal tissues. The passage of UFPM/NPs from mothers to fetuses is documented and fingerprinting placental single particle composition could be useful for postnatal risk assessments. Fetal brain combustion and industrial NPs raise medical concerns about prenatal and postnatal health, including neurological and neurodegenerative lifelong consequences."

Environmental medicine Placental impairment Neurodevelopmental disorders Fetal brains Erythroblasts Preeclampsia Nanoparticles NPs extracellular vesicles Petrochemical pollution Villahermosa Tabasco BIOLOGÍA Y QUÍMICA QUÍMICA BIOQUÍMICA BIOQUÍMICA

Universal fixation system for pad printing of plastic parts

JOSE ALEJANDRO FERNANDEZ RAMIREZ (2023, [Artículo])

Pad printing is used in automotive, medical, electrical and other industries, employing diverse materials to transfer a 2D image onto a 3D object with different sizes and geometries. This work presents a universal fixation system for pad printing of plastic parts (UFSP4) in response to the needs of small companies that cannot afford to invest in the latest technological advances. The UFSP4 comprises two main subsystems: a mechanical support system (i.e., support structure, jig matrix and braking system) and a control system (i.e., an electronic system and an electric-hydraulic system). A relevant feature is the combination of a jig matrix and jig pins to fixate complex workpieces with different sizes. Using finite element analysis (FEA), in the mesh convergence, the total displacement converges to 0.00028781 m after 12,000 elements. The maximum equivalent stress value is 1.22 MPa for the polycarbonate plate in compliance with the safety factor. In a functionality test of the prototype performed in a production environment for one hour, the jigs fixed by the plate did not loosen, maintaining the satisfactory operation of the device. This is consistent with the displacement distribution of the creep analysis and shows the absence of the creep phenomenon. Based on FEA that underpinned the structural health computation of the braking system, the prototype was designed and built, seeking to ensure a reliable and safe device to fixate plastic parts, showing portability, low-cost maintenance and adaptability to the requirements of pad printing of automotive plastic parts.

Use of AI tools declaration: The authors declare they have not used Artificial Intelligence (AI) tools in the creation of this article.

Acknowledgments: To the company Plásticos Decorados and Centro de Tecnología Avanzada (CIATEQ A.C.) for the facilities and support to carry out this work. To the Consejo Nacional de Humanidades, Ciencias y Tecnologías (CONAHCYT) for a Ph.D. scholarship support number 500839 and CONAHCYT SNI.

Conflict of interest: The authors declare there are no conflicts of interest.

Modular fixtures Jig matrix Prototype design Pad printing Fixture methods INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS OTRAS ESPECIALIDADES TECNOLÓGICAS OTRAS OTRAS

Sustainable urban mobility: An alternative for air pollution in the Guadalajara Metropolitan Area

José Antonio Olivares Mendoza Clemente Hernandez-Rodriguez Luz Alicia Jimenez Portugal (2023, [Artículo, Artículo])

The objective of this paper is to evaluate whether the low-carbon transport strategy (subway, rapid transit bus system -Macrobús-, trolleybus, and shared bicycles) implemented in the Guadalajara Metropolitan Area (AMG) from 2000 to 2019 improves air quality. Sustainable urban mobility is the movement of people in cities in a way that generates the least impact on the environment. We analyze three actions of government intervention in the same sense. This is the first study for Guadalajara, the third-largest city in Mexico. We use robust Newey-West estimators and endogenously model pollution disruptions using the Bai Perron approach. Our results suggest that this type of public transport reduces SO2, NO2, O3, and CO, though we find an increase in PM10. We also identified that when the service of the first line of the Bus Rapid Transit was consolidated CO, O3 and PM10 decreased. In addition, the improvement in the connectivity of the bus network with the subway means that only NO2 diminished. Finally, the entry into operation of the shared bicycle program reduced PM10, while increasing O3 and in SO2. In short, sustainable urban mobility is an alternative to making the transit of people efficient, while mitigating air pollution in the AMG.

Contaminación del aire Transporte urbano Bicicletas compartidas Autobuses de tránsito rápido Metro CIENCIAS SOCIALES CIENCIAS SOCIALES Air pollution Urban transport Bus Rapid Transit

On-farm storage loss estimates of maize in Kenya using community survey methods

Hugo De Groote Anani Bruce (2023, [Artículo])

Maize is the most important staple in sub-Saharan Africa (SSA), with highly seasonal production. High storage losses affect food security, but good estimations are lacking. A new method using focus group discussions (FGDs) was tested with 121 communities (1439 farmers, 52% women) in Kenya's six maize-growing zones, to estimate the maize losses to storage pests and analyze farmer practices. As control strategies, half of the farmers used chemical pesticides (49%), while hermetic bags (16%) and botanicals (15%) were also popular. Relative loss from weevils in the long rains was estimated at 23%, in the short rains 18%, and annually 21%. Fewer farmers were affected by the larger grain borer (LGB) than by maize weevils: 42% in the long rainy season and 32% in the short rainy season; losses from LGB were also smaller: 19% in the long season, 17% in the short season, and 18% over the year. Total storage loss, from both species combined, was estimated at 36%, or 671,000 tonnes per year. The greatest losses occur in the humid areas, especially the moist mid-altitudes (56%), and with smaller loss in the drylands (20–23%). Extrapolating the point data and overlaying with the maize production map shows the geographic distribution of the losses, with the most important area found around Lake Victoria. FGDs provide convenient and cheap tools to estimate storage losses in representative communities, but a total loss estimate of 36% is higher than is found in other studies, so its accuracy and framing effects need to be assessed. We conclude that storage pests remain a major problem, especially in western Kenya, and that the use of environmentally friendly technologies such as hermetic storage and botanicals needs more attention, both by the public extension service and private agrodealers.

Larger Grain Borer Maize Weevil CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA MAIZE STORAGE LOSSES PESTS SURVEY METHODS

Agua, gobierno y minería: ¿Por qué el medio ambiente no es prioridad en la agenda pública?

ANA MARIA HERRERA CRUZ JUAN ANTONIO BARRON SEVILLA (2022, [Artículo])

Valorar la escasez del agua, la regulación gubernamental y a la minería, es poner en la balanza la famosa relación costo beneficio. No es necesario ser un erudito para saber cuál es la elección de nuestros gobiernos Prevaleciendo en este caso la economía y un aparente desarrollo contra la preservación del medio ambiente. Lo que resulta urgente es un nuevo planteamiento de prioridades para la resolución de problemas que aquejan el acceso al agua como derecho humano.

ESCASEZ DEL AGUA IMPACTO MINERO MEXICO POLITICAS AMBIENTALES INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS TECNOLOGÍA MINERA OTRAS OTRAS