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Does access to improved grain storage technology increase farmers' welfare? Experimental evidence from maize farming in Ethiopia

Hugo De Groote Bart Minten (2024, [Artículo])

Seasonal price variability for cereals is two to three times higher in Africa than on the international reference market. Seasonality is even more pronounced when access to appropriate storage and opportunities for price arbitrage are limited. As smallholder farmers typically sell their production after harvest, when prices are low, this leads to lower incomes as well as higher food insecurity during the lean season, when prices are high. One solution to reduce seasonal stress is the use of improved storage technologies. Using data from a randomised controlled trial, in a major maize-growing region of Western Ethiopia, we study the impact of hermetic bags, a technology that protects stored grain against insect pests, so that the grain can be stored longer. Despite considerable price seasonality—maize prices in the lean season are 36% higher than after harvesting—we find no evidence that hermetic bags improve welfare, except that access to these bags allowed for a marginally longer storage period of maize intended for sale by 2 weeks. But this did not translate into measurable welfare gains as we found no changes in any of our welfare outcome indicators. This ‘near-null’ effect is due to the fact that maize storage losses in our study region are relatively lower than previous studies suggested—around 10% of the quantity stored—likely because of the widespread use of an alternative to protect maize during storage, for example a cheap but highly toxic fumigant. These findings are important for policies that seek to promote improved storage technologies in these settings.

Hermetic Storage Randomised Controlled Trial CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA STORAGE PILOT FARMS SEASONALITY WELFARE MAIZE

Corrección de defectos óseos en el área de Ingeniería tisular

Correction of bone defects by tissue Engineering

ROSA ALICIA SAUCEDO ACUÑA MONICA GALICIA GARCIA JUDITH VIRGINIA RIOS ARANA SIMON YOBANNY REYES LOPEZ (2012, [Artículo])

Hoy en día, los defectos óseos representan uno de los casos de mayor impacto en la salud debido a la frecuencia con que éstos ocurren a causa de traumatismos, fracturas, enfermedades congénitas o degenerativas. En la actualidad, los implantes de tejido óseo de gran volumen se encuentran severamente restringidos a causa de las limitaciones de difusión en la interacción con el ambiente del huésped para los nutrientes, intercambio gaseoso y eliminación de desechos. Es por ello que la corrección de los defectos óseos ha cobrado gran importancia en el área de Ingeniería tisular buscando mejorar las estrategias clínicas para su tratamiento. El propósito de esta revisión es proporcionar un panorama general del desarrollo de andamios para la regeneración de tejido óseo, mostrando los avances logrados en los ensayos in vitro e in vivo en la última década

Currently, bone defects cases represent a major impact on health due to how often they occur because of trauma, fractures, congenital or degenerative diseases. Now, bone implants to large volume are severely restricted because of the diffusion limitations in the interaction

with the environment of the host for nutrients, gas exchange and waste disposal. That is why the correction of bone defects has become very important in the field of tissue engineering looking to improve clinical strategies for treatment. The purpose of this review is to provide an overview of the development of scaffolds for bone tissue regeneration, showing the progress made in the in vitro and in vivo in recent decades.

MEDICINA Y CIENCIAS DE LA SALUD Ingeniería tisular regeneración ósea Andamio Tissue engineering Bone regeneration Scaffolds

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

Diseño de riego por melgas empleando las ecuaciones de Saint-Venant, y Green y Ampt

Heber Saucedo MANUEL ZAVALA TREJO CARLOS FUENTES RUIZ (2015, [Artículo])

Se presenta un método de diseño de riego por melgas basado en la aplicación de un modelo que emplea las ecuaciones de Saint-Venant, para describir el flujo del agua sobre el suelo, y la ecuación de Green y Ampt, para representar el flujo del agua en el suelo. La principal ventaja del modelo presentado es el poco tiempo de cómputo que requiere para su aplicación, en comparación con el necesario para ejecutar un modelo hidrodinámico completo reportado en la literatura, mismo que emplea las ecuaciones de Saint-Venant para el flujo del agua sobre el suelo, acopladas internamente con la ecuación de Richards, que permite modelar el flujo del agua en el suelo.

Riego por inundación controlada Modelos matemáticos Gasto óptimo CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA

Chemically modified nanoparticles for enhanced antioxidant and antimicrobial properties with cinnamon essential oil

Aaron Azael Lopez Cano VERONICA MARTINEZ AGUILAR Mariana Peña-Juárez Ricardo López Esparza Enrique Delgado Alvarado Emmanuel Gutierrez MAYRA DEL ANGEL MONROY Elias Perez Agustin L. Herrera-May JOSE AMIR GONZALEZ CALDERON (2023, [Artículo])

We explored the potential of different nanoparticles (TiO2, CaCO3, and Al2O3), considering their pure form and modified with cinnamon essential oil (CEO). These materials were characterized using various techniques, including FTIR spectroscopy, XRD analysis, TGA, and SEM. The interaction between CEO and nanoparticles changed depending on the nanoparticle type. Al2O3 nanoparticles exhibited the strongest interaction with CEO, increasing their antioxidant capacity by around 40% and their transfer of antimicrobial properties, particularly against Gram-negative bacteria. In contrast, TiO2 and CaCO3 nanoparticles showed limited interaction with CEO, resulting in lower antioxidant capacity and antimicrobial activity. Incorporating pure and CEO-modified nanoparticles into polylactic acid (PLA) films improved their mechanical and thermal properties, which are suitable for applications requiring greater strength. This research highlights the potential of metal oxide nanoparticles to enhance the antimicrobial and antioxidant capabilities of polymers. In addition, incorporating cinnamon essential oil can increase the antioxidant and antimicrobial effectiveness of the metal oxide nanoparticles and improve the mechanical and thermal properties of PLA films. Thus, these PLA films exhibit favorable characteristics for active packaging applications.

Author contributions: conceptualization, V.M.-A. and J.A.G.-C.; formal analysis, A.A.L.-C., V.M.-A., M.G.P.-J. and M.D.A.-M.; funding acquisition, A.L.H.-M.; methodology, A.A.L.-C. and V.M.-A.; investigation, E.P.; supervision, R.L.-E., E.D.-A., and E.J.G.-C.; validation, A.L.H.-M. and J.A.G.-C.; writing—original draft, V.M.-A.; writing—review and editing, M.G.P.-J. and J.A.G.-C. All authors have read and agreed to the published version of the manuscript.

Funding: J.A. Gonzalez-Calderon thanks CONAHCYT for supporting the Catedras-CONAHCYT Program, and Verónica Martinez thanks CONAHCYT for the Doctoral Fellowship. The authors also want to thank CONAHCYT for funding the project CF2019 265239 “Ciencia de Frontera”, which made this work possible.

Institutional review board statement: Not applicable.

Informed consent statement: Not applicable.

Data availability statement: Data is contained within the article.

Acknowledgments: The authors acknowledge Claudia Hernández and Rosa Lina Tovar for their support during the XRD and SEM analyses.

Conflicts of interest: The authors declare no conflict of interest.

Disclaimer/publisher’s note: The statements, opinions and data contained in all publications are solely those of the individual author(s) and contributor(s) and not of MDPI and/or the editor(s). MDPI and/or the editor(s) disclaim responsibility for any injury to people or property resulting from any ideas, methods, instructions or products referred to in the content.

Cinnamon essential oil Antioxidant activity Antimicrobial properties Nanoparticles Polylactic acid films INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS OTRAS ESPECIALIDADES TECNOLÓGICAS OTRAS OTRAS

Gasto óptimo en riego por melgas

Heber Saucedo MANUEL ZAVALA TREJO CARLOS FUENTES RUIZ LEONID VLADIMIR CASTANEDO GUERRA (2013, [Artículo])

Se verifica la relación, básicamente lineal, que existe entre la longitud de una melga y el gasto óptimo de riego, que es el gasto que se debe aplicar para obtener un valor máximo en el coeficiente de uniformidad, que produzca valores elevados de las eficiencias de aplicación y de requerimiento de riego. Dicha verificación se realiza mediante la aplicación de un modelo hidrodinámico completo, empleando métodos numéricos, que hace uso de las ecuaciones de Saint-Venant para la descripción del flujo del agua sobre el suelo, acopladas internamente con la ecuación de Richards, que permite modelar el flujo del agua en el suelo. De acuerdo con los resultados obtenidos mediante la aplicación del modelo para diez tipos de suelo diferentes, se incluyen cuadros de diseño operativo del riego por melgas.

Riego por melgas Gasto óptimo CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA

Agroecology can promote climate change adaptation outcomes without compromising yield in smallholder systems

Sieglinde Snapp Yodit Kebede Eva Wollenberg (2023, [Artículo])

A critical question is whether agroecology can promote climate change mitigation and adaptation outcomes without compromising food security. We assessed the outcomes of smallholder agricultural systems and practices in low- and middle-income countries (LMICs) against 35 mitigation, adaptation, and yield indicators by reviewing 50 articles with 77 cases of agroecological treatments relative to a baseline of conventional practices. Crop yields were higher for 63% of cases reporting yields. Crop diversity, income diversity, net income, reduced income variability, nutrient regulation, and reduced pest infestation, indicators of adaptative capacity, were associated with 70% or more of cases. Limited information on climate change mitigation, such as greenhouse gas emissions and carbon sequestration impacts, was available. Overall, the evidence indicates that use of organic nutrient sources, diversifying systems with legumes and integrated pest management lead to climate change adaptation in multiple contexts. Landscape mosaics, biological control (e.g., enhancement of beneficial organisms) and field sanitation measures do not yet have sufficient evidence based on this review. Widespread adoption of agroecological practices and system transformations shows promise to contribute to climate change services and food security in LMICs. Gaps in adaptation and mitigation strategies and areas for policy and research interventions are finally discussed.

CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CLIMATE CHANGE CROPS FOOD SUPPLY GAS EMISSIONS GREENHOUSE GASES FARMING SYSTEMS AGROECOLOGY FOOD SECURITY LESS FAVOURED AREAS SMALLHOLDERS YIELDS NUTRIENTS BIOLOGICAL PEST CONTROL CARBON SEQUESTRATION LEGUMES

Desarrollo de metodologías de laboratorio para la detección de contaminantes emergentes y su identificación en cuerpos de agua (agua sedimento) y en aguas residuales (en influente, efluente y los de PTAR)

MARTHA AVILÉS FLORES GABRIELA ELEONORA MOELLER CHAVEZ NORMA RAMIREZ SALINAS (2012, [Documento de trabajo])

El presente trabajo consiste, en la implementación de metodologías de: microcistina LR por cromatografía de ultra alta resolución; nonilfenol por cromatografía gases espectrometría de masas y surfactantes por espectrofotometría de ultravioleta visible. El proyecto presente tiene además la validación de las metodologías de análisis de fármacos (Amoxicilina, Gemfibrozil, Acido Clofíbrico) y Hormonas (Estrona, 17 ß-estradiol, α-etinil estradiol) con muestras reales en la Cuenca Balsas en épocas de estiaje y de lluvias, específicamente en el río Atoyac uno de los ríos más importantes y donde se desarrollan una variada gama de actividades, evaluándose la probable presencia de fármacos en los sistemas de tratamiento de agua residual en influente y efluente.

Informes de proyectos Análisis del agua Cromatografía de gases Espectrometría de masa Contaminantes emergentes Tratamiento de aguas residuales Río Atoyac, Puebla Río Atoyac, Tlaxcala INGENIERÍA Y TECNOLOGÍA

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)