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Optimizing nitrogen fertilizer and planting density levels for maize production under current climate conditions in Northwest Ethiopian midlands

Kindie Tesfaye Dereje Ademe Enyew Adgo (2023, [Artículo])

This study determined the most effective plating density (PD) and nitrogen (N) fertilizer rate for well-adapted BH540 medium-maturing maize cultivars for current climate condition in north west Ethiopia midlands. The Decision Support System for Agrotechnology Transfer (DSSAT)-Crop Environment Resource Synthesis (CERES)-Maize model has been utilized to determine the appropriate PD and N-fertilizer rate. An experimental study of PD (55,555, 62500, and 76,900 plants ha−1) and N (138, 207, and 276 kg N ha−1) levels was conducted for 3 years at 4 distinct sites. The DSSAT-CERES-Maize model was calibrated using climate data from 1987 to 2018, physicochemical soil profiling data (wilting point, field capacity, saturation, saturated hydraulic conductivity, root growth factor, bulk density, soil texture, organic carbon, total nitrogen; and soil pH), and agronomic management data from the experiment. After calibration, the DSSAT-CERES-Maize model was able to simulate the phenology and growth parameters of maize in the evaluation data set. The results from analysis of variance revealed that the maximum observed and simulated grain yield, biomass, and leaf area index were recorded from 276 kg N ha−1 and 76,900 plants ha−1 for the BH540 maize variety under the current climate condition. The application of 76,900 plants ha−1 combined with 276 kg N ha−1 significantly increased observed and simulated yield by 25% and 15%, respectively, compared with recommendation. Finally, future research on different N and PD levels in various agroecological zones with different varieties of mature maize types could be conducted for the current and future climate periods.

Maize Model Planting Density CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA MAIZE MODELS SPACING NITROGEN FERTILIZERS YIELDS

“Mexico half way of making”: Carlos Chávez and the foundation of the National Institute of Fine Arts (INBA) (1945-1947)

Ana Garduño (2023, [Artículo, Artículo])

I am focusing on the interaction between a cultural agent, Carlos Chávez, and the government elite, related to the circumstances of the enunciation of a public and official organism, INBA (The National Institute of Fine Arts), because I assume that political relations are fundamental to understand a process that endorsed the official culture as an appendage of politics. In spite of its relevance, this subject has not been studied. Based on archival documentation (at the National Archive of Mexico and the archive of INBA) I am examining the cultural policies derived from the foundation of INBA. Due to the current pandemic situation, it was not possible to consult other documental sources. I am formulating that the concept of “high culture” was at the core of a wider conflict between governmental interests and those of representative social actors, and I conclude that this obstacle would have conferred a major political and symbolical importance to the Institute, and consequently, would restrict its budget.

Carlos Chávez INBA Agentes culturales Políticas institucionales Centralización artística HUMANIDADES Y CIENCIAS DE LA CONDUCTA HUMANIDADES Y CIENCIAS DE LA CONDUCTA Foundation of the National Institute of Fine Arts in Mexico (INBA), Cultural agents Institutional policies Artistic centralization

Telemedicina y Brigada Mater en San Luis Potosí, un Sistema de Atención Referenciada para el Control del Riesgo Materno

Miriam de los Angeles De la Rosa Velázquez (2020, [Tesis de maestría])

"Esta tesis apunta a explorar las estrategias enfocadas a la política pública de atención a la salud materna desde un enfoque sistémico. Continúa con una serie de apartados que se enfocan en describir las acciones en los diferentes niveles de atención para comprender las partes que conforman el proceso y los actores que participan, y para explicarlo se presenta el resultado de una intervención organizacional que se realizó durante el trabajo de campo en un hospital especialista en salud materna, así como un análisis de la atención materna a partir del marco lógico."

Higiene pública -- Servicios -- San Luis Potosí, México Hospitales -- Salud -- Políticas públicas -- México Mujeres en México -- San Luis Potosí -- Salud e higiene Telemedicina -- Maternidad -- Aspectos sociales CIENCIAS SOCIALES CIENCIA POLÍTICA CIENCIA POLÍTICA

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

Gráfica de protesta: PuntosB, Lapiztola y La Guillotina. Un análisis entre el cuerpo y el espacio en la imagen de protesta

Jorge Gabriel Ortiz Leroux (2023, [Capítulo de libro])

Capítulo número 5 de la Sección Imágenes y representaciones.

El objetivo del presente texto es el de mostrar como la obra emanada de colectivos de análisis del espacio social de la protesta, permite reconocer las claves que relacionan al espacio con los actores que lo ocupan. Asimismo, se pretende abordar cómo el conflicto que se interpone entre los actores de la protesta define sus magnitudes y reelabora sus disposiciones y sus formas de entrecruzamiento en relación con la presencia de la imagen. Asimismo, la representación imaginaria y visual del espacio permite ver a la ciudad como un laboratorio, que puede también ser registrado, interpretado y resituado respecto a los discursos hegemónicos. Los proyectos visuales que aquí abordamos representan un trabajo que a través de los años ha expresado su visión sobre las realidades sociales y políticas de nuestro país, en las que el conflicto aparece como telón de fondo de la creación e interpretación visual de esas realidades. La interacción entre política y estética tiene como escenario el espacio público y la ciudad, que fungen como trasfondo para la expresión de formas imaginarias y que conforman en sí mismas el sentido de los reclamos y las transformaciones gestadas. Mirando a la ciudad, observamos sus cambios y las formas de relación, cada vez más complejas, que se viven en ella.

Public spaces--Social aspects--Mexico. Dissident art. Protest movements--Mexico--Posters. Graphic arts--Political aspects--Mexico. Political posters, Mexican--20th century. Espacios públicos -- México. Arte disidente. Movimientos de protesta. Carteles políticos mexicanos. HT185 HUMANIDADES Y CIENCIAS DE LA CONDUCTA CIENCIAS DE LAS ARTES Y LAS LETRAS TEORÍA, ANÁLISIS Y CRÍTICA DE LAS BELLAS ARTES

DEPRESSIVE SYMPTOMS (DS) AND CITIES: A SOCIOECONOMIC PERSPECTIVE FOR THE MEXICAN CASE

Jorge López Martínez Déborah Féber González (2023, [Artículo, Artículo])

This article presents an analysis of the proportion of the population that lives in the 20 top cities of Mexico. Population that suffers from moderate to severe Depressive Symptoms (DS) in relation to urban and socioeconomic factors typical of urban territories and comparing them with people living in rural or non-urban environments that suffers DS. To check this, we generated the Complex Index of Socioeconomic and Urban Conditions (CISUC), based on the Mind the GAPS framework, a model that relates the susceptibility or prevention of mental illness in cities based on urban factors, we also used socioeconomic indicators that exist in Mexican cities. For the construction of the ICCSU database, we used data from the National Health and Nutrition Survey in the years 2006, 2012 and 2018-19 and the data of the Mexican Institute for Competitiveness, A.C. and National Institute of Statistics and Geography in the same years. The results obtained from CISUC were reinforced with the use of a panel data model. The findings that we obtained reveal that there is a more important correlation between cities and people who suffer from moderate to severe DS than in rural areas, a condition that intensifies with the socioeconomic conditions of the population, for example, their socioeconomic stratum, their gender, and present urban marginalization. This allows to generate future discussions about other types of diseases such as anxiety, depression, stress, loneliness, and schizophrenia for large population groups. The panel model yields a lower goodness of adjustment, due to the lack of more time points, however, it points out that improvements in socioeconomic and urban conditions slightly reduce depressive symptoms.

mental health depressive symptoms (DS) urban marginalization socioeconomic factors cities salud mental sintomatología depresiva (SD) ciudades marginación urbana factores socioeconómicos CIENCIAS SOCIALESCIENCIAS SOCIALES CIENCIAS SOCIALES

Los médicos costarricenses formados en México durante el cardenismo: retorno e inserción laboral (1934-1961)

Costa Rican doctors trained in Mexico during the Cardenismo: return and labor insertion (1934-1961)

Marco Calderón-Blanco (2021, [Artículo])

El presente trabajo analiza el retorno de los estudiantes costarricenses que viajaron a México durante el cardenismo para cursar la carrera de medicina, con el fin de determinar su inserción laboral en el sistema de salud costarricense entre las décadas de 1940 y 1960. Se exploran las circunstancias que giraron alrededor del retorno y la inserción laboral de dichos profesionales. Al respecto, se evidencia que la integración a la fuerza de trabajo en el Hospital San Juan de Dios permitió un rápido ascenso en el escalafón médico. Esta dinámica posibilitó que un número considerable de los médicos tratados en el presente estudio ocupara puestos de poder en instituciones de salud costarricenses, situación que llevó a que se integraran al proceso de creación de la Escuela de Medicina de la Universidad de Costa Rica, la cual entró en funciones en el año de 1961.

The present work analyzes the return of Costa Rican students who traveled to Mexico during the cardenismo period to study medicine, in order to determine their labor insertion in the Costa Rican health system between the 1940s and 1960s. The circumstances surrounding the return and work insertion of these professionals are explored. In this regard, it is evident that the integration to the workforce of the San Juan de Dios Hospital allowed a rapid ascent in the medical ladder. This dynamic made it possible for a considerable number of the doctors treated in this study to hold positions of power in Costa Rican health institutions, a situation that led to their integration into the process of creating the University of Costa Rica’s School of Medicine, which became operational in 1961.

HUMANIDADES Y CIENCIAS DE LA CONDUCTA Medicina social Médicos costarricenses Cardenismo Retorno Inserción laboral Social medicine Costa Rican doctors Lázaro Cardenas government Return Labor insertion

Using an incomplete block design to allocate lines to environments improves sparse genome-based prediction in plant breeding

Osval Antonio Montesinos-Lopez ABELARDO MONTESINOS LOPEZ RICARDO ACOSTA DIAZ Rajeev Varshney Jose Crossa ALISON BENTLEY (2022, [Artículo])

Genomic selection (GS) is a predictive methodology that trains statistical machine-learning models with a reference population that is used to perform genome-enabled predictions of new lines. In plant breeding, it has the potential to increase the speed and reduce the cost of selection. However, to optimize resources, sparse testing methods have been proposed. A common approach is to guarantee a proportion of nonoverlapping and overlapping lines allocated randomly in locations, that is, lines appearing in some locations but not in all. In this study we propose using incomplete block designs (IBD), principally, for the allocation of lines to locations in such a way that not all lines are observed in all locations. We compare this allocation with a random allocation of lines to locations guaranteeing that the lines are allocated to

the same number of locations as under the IBD design. We implemented this benchmarking on several crop data sets under the Bayesian genomic best linear unbiased predictor (GBLUP) model, finding that allocation under the principle of IBD outperformed random allocation by between 1.4% and 26.5% across locations, traits, and data sets in terms of mean square error. Although a wide range of performance improvements were observed, our results provide evidence that using IBD for the allocation of lines to locations can help improve predictive performance compared with random allocation. This has the potential to be applied to large-scale plant breeding programs.

CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA Bayes Theorem Genome Inflammatory Bowel Diseases Models, Genetic Plant Breeding

Influence of poverty concerns on demand for healthier processed foods: A field experiment in Mexico City

Marrit Van den Berg Jason Donovan (2023, [Artículo])

Living in poverty can present cognitive biases that exacerbate constraints to achieving healthier diets. Better diets could imply food choice upgrades within certain food categories, such as electing processed foods with an improved nutritional profile. This study evaluated the influence of monetary and health concerns on the willingness to pay (WTP) for healthier processed foods in a low-income section of Mexico City. We employed priming techniques from the scarcity literature, which are applied for the first time to healthier food purchasing behaviours in low-income settings. Our predictions are based on a dual system framework, with choices resulting from the interaction of deliberative and affective aspects. The WTP was elicited through a BDM mechanism with 423 participants. Results showed that induced poverty concerns reduced the valuations of one of the study's healthier food varieties by 0.17 standard deviations. The latter effect did not differ by income level. The WTP for a healthier bread product but one with relatively high sugar and fat content was reduced by induced poverty concerns only among certain consumers without bread purchasing restrictions (78% of the sample). Potential mechanisms were assessed through regression analysis and structural equation modelling. The relationship between poverty concerns and WTP was mediated by increased levels of stress. While we could not rule out impact on cognitive load, it was not deemed a mediator in this study. Our findings signal that improvements in economic and psychological well-being among low-income consumers may aid to increase their demand for healthier processed foods.

Healthier Diets Poverty Psychology Dual System Model CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA DIET POVERTY PSYCHOLOGY STRESS WILLINGNESS TO PAY

Big data, small explanatory and predictive power: Lessons from random forest modeling of on-farm yield variability and implications for data-driven agronomy

Martin van Ittersum (2023, [Artículo])

Context: Collection and analysis of large volumes of on-farm production data are widely seen as key to understanding yield variability among farmers and improving resource-use efficiency. Objective: The aim of this study was to assess the performance of statistical and machine learning methods to explain and predict crop yield across thousands of farmers’ fields in contrasting farming systems worldwide. Methods: A large database of 10,940 field-year combinations from three countries in different stages of agricultural intensification was analyzed. Random effects models were used to partition crop yield variability and random forest models were used to explain and predict crop yield within a cross-validation scheme with data re-sampling over space and time. Results: Yield variability in relative terms was smallest for wheat and barley in the Netherlands and for wheat in Ethiopia, intermediate for rice in the Philippines, and greatest for maize in Ethiopia. Random forest models comprising a total of 87 variables explained a maximum of 65 % of cereal yield variability in the Netherlands and less than 45 % of cereal yield variability in Ethiopia and in the Philippines. Crop management related variables were important to explain and predict cereal yields in Ethiopia, while predictive (i.e., known before the growing season) climatic variables and explanatory (i.e., known during or after the growing season) climatic variables were most important to explain and predict cereal yield variability in the Philippines and in the Netherlands, respectively. Finally, model cross-validation for regions or years not seen during model training reduced the R2 considerably for most crop x country combinations, while for wheat in the Netherlands this was model dependent. Conclusion: Big data from farmers’ fields is useful to explain on-farm yield variability to some extent, but not to predict it across time and space. Significance: The results call for moderate expectations towards big data and machine learning in agronomic studies, particularly for smallholder farms in the tropics where model performance was poorest independently of the variables considered and the cross-validation scheme used.

Model Accuracy Model Precision Linear Mixed Models CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA MACHINE LEARNING SUSTAINABLE INTENSIFICATION BIG DATA YIELDS MODELS AGRONOMY