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Propaganda against Mexican women married to Chinese immigrants in Chihuahua 1920-1940
Vladimir Alejandro Armendáriz Romero Jesús Adolfo Trujillo Holguín (2023, [Artículo, Artículo])
At the turn of the 20th century and at the beginning of the new revolutionary government stage in Mexico, the press was an effective way to disseminate propaganda for the nationalist ideology of the State. An important part of this diffusion covered the question of the racial constitution of the mexicans, which led to the need to convince the public that it was important to determine controls over women and with whom they married since they were responsible for the reproduction of the Mexican race. Therefore, a mixture of races considered undesirable, such as the Chinese, was detestable. This propaganda occurred in the context of national anti-Chinese and anti-Jewish campaigns in which they wanted to expel these foreigners on the pretext that their presence and mixing with them would result in degeneration. In Chihuahua there are indications of this propaganda, but also that women married to Chinese resisted this campaign against their families.
Racism gender social control mestizophobia propaganda Racismo género control social mestizofobia HUMANIDADES Y CIENCIAS DE LA CONDUCTA HUMANIDADES Y CIENCIAS DE LA CONDUCTA
Evaluation of sunlight and humidity protection of a bioherbicide for Eichornia crassipes biocontrol
MARICELA MARTINEZ JIMENEZ MARIA ANTONIETA GOMEZ BALANDRA MARIA DEL PILAR SALDAÑA FABELA (2015, [Artículo])
C. piaropi (Cercospora piaropi) and A. zonatum (Acremonium zonatum) have proved to be effective in reducing water hyacinth growth. However, efficacy of these fungi in field is limited by the effect of solar UV (ultraviolet) light and desiccation. In this study, three compounds used as sunscreens and one seed plant that produce mucilage were tested for their effects on the infection produced by C. piaropi and A. zonatum inoculum under laboratory and field conditions. In laboratory conditions, TiO2 (titanium dioxide) and metamucil did not inhibit C. piaropi and A. zonatum viability. Moreover, the addition of TiO2 and metamucil to the inoculum suspension increased fungi infection. The protective effect of TiO2 and metamucil was more evident when the inoculum suspension was applied 4 h before sunset. These results suggest that addition of TiO2 and metamucil provides necessary humidity and solar protection for increasing C. piaropi and A. zonatum infection on water hyacinth plants.
Lirios acuáticos Radiación solar Dióxido de titanio C. piaropi A. zonatum BIOLOGÍA Y QUÍMICA
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
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
GUADALUPE MARISOL MANDUJANO SALGADO (2021, [Tesis de maestría])
"Este trabajo confronta analíticamente los discursos críticos publicados en torno a
Ramón López Velarde en un periodo de tiempo en el que, se estipula, se conformó su figura
como poeta y como identificación cultural asociada a las letras mexicanas de principios de
siglo XX."
López Velarde, Ramón, 1888-1921 -- Crítica e interpretación Literatura mexicana -- Historia y crítica -- Siglo XX Poetas mexicanos -- Siglo XX CIENCIAS SOCIALES CIENCIAS SOCIALES
Principles of field experimentation
Berhanu Tadesse Ertiro (2023, [Objeto de congreso])
CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA FIELD EXPERIMENTATION EXPERIMENTAL DESIGN RANDOMIZED BLOCK DESIGN LATTICE DESIGN PLANT BREEDING
Rainfall water quality at Atlixco, Puebla
Margarita Teutli Andrés Armando Sánchez Erendira Moreno Gutierrez (2021, [Artículo, Artículo])
This work reports the follow up of rainfall water quality at Atlixco, Puebla during the 2018 season. The main objective of this work was to evaluate how height and pollutants define the quality of water precipitated. Samples were collected at the roof of a house in Atlixco center, and others at the roof of a convent located at the San Miguel Hill, this represents a 44 m difference in height. Chemical composition was analyzed for 19 physicochemical parameters using gravimetric and spectrophotometric techniques. Obtained results were compared with drinking water standards finding that Pb and Cd contents are exceeded. Also, it was found a strong contribution of terrestrial sources since the marine rates are above unit, as well as excess concentrations whose values go from negative to positive. Finally, Pearson correlation was obtained finding that most of chemical parameters correlations are in disagreement for both sites, fact which confirms that ionic content is strongly influenced by anthropogenic sources.
rainfall ionic content marine rates excess concentrations Lluvia contenido iónico cociente marino concentración en exceso Estudios urbanos CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA
Fundamentos de radares meteorológicos: aspectos modernos (segunda de dos partes)
MOISES MICHEL ROSENGAUS MOSHINSKY (1995, [Artículo])
En la primera parte se trataron principios de funcionamiento y conceptos esenciales para la correcta interpretación de productos de radar en cuanto a sus características clásicas, aquellas que los radares meteorológicos presentan desde su concepción después de la II Guerra Mundial. En esta segunda parte se hace lo propio para los aspectos modernos de los radares meteorológicos, incluyendo el control y procesamiento digital, la capacidad Doppler y la doble polarización. Se discuten sus productos, la operación rutinaria de un radar meteorológico moderno, su relación con otros sistemas de medición similares, así como sus aplicaciones e impacto en la hidrología.
Radares meteorológicos Operación Meteorología CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA
DENISE ENCARNACION MAYORAL NORIEGA (2023, [Tesis de maestría])
Existen factores ambientales de naturaleza física, química o biológica que afectan directamente la alimentación de los peces. Por ejemplo, las altas densidades de cultivo pueden generar estrés en los organismos, resultando en la merma del consumo de alimento y por ende su crecimiento. Sin embargo, algunas especies toleran altas densidades formando un grupo o cardumen que les confiere un mejor desempeño. Otro factor que afecta el comportamiento de algunas especies es la coloración de los tanques de cultivo; demostrando la necesidad de utilizar tanques con un entorno físico adecuado para la especie a cultivar. Actualmente, M. saxatilis se produce en tanques en laboratorio y se engorda en jaulas marinas en Baja California; así que existe un gran interés por mejorar su crecimiento y eficiencia alimenticia. Por ello, el objetivo de esta investigación fue evaluar tres densidades de cultivo (alta: 6.2 kg·m-3, media: 3.1 kg·m-3 y baja: 1.5 kg·m-3) y dos colores de tanque (azul celeste y negro) en el crecimiento, supervivencia, utilización del alimento, índices corporales y concentración de cortisol y glucosa de juveniles de lobina rayada en agua marina para su mantenimiento en laboratorio durante nueve semanas. Los resultados demostraron que los organismos obtuvieron el mayor crecimiento en peso en la densidad media, indistintamente del color del tanque. Asimismo, la densidad afectó significativamente los índices hepatosomático y liposomático, ya que disminuyeron conforme aumentó la densidad. El color del tanque influyó de manera importante en el consumo de alimento (azules: 37.4 ± 1.9 g·pez-1; negros: 35.9 ± 2.0 g·pez-1). La interacción de los factores afectó la TCE, TCA y TEP. Las concentraciones de cortisol (81.8 ± 22.5 ng·ml-1) y glucosa (83.2 ± 11.4 mg·100 ml-1) fueron similares en todos los tratamientos y relativamente bajas para la especie. En conclusión, se logró elucidar bajo qué condiciones de cultivo en laboratorio los organismos lograron superar los factores de estrés sin comprometer su crecimiento y supervivencia, reflejándose en un mejor desempeño biológico. Se recomienda utilizar tanques azules o negros con densidades iniciales de 4.2 kg·m-3 o 233 peces·m-3 para el cultivo de juveniles de M. saxatilis en agua salada bajo condiciones de laboratorio.
Environmental factors of a physical, chemical or biological nature such as high stocking densities can directly affect fish feeding and generate stress in organisms, resulting in a decrease in food intake and therefore growth. However, some species tolerate high densities, forming a group or shoal resulting in better overall performance. Another factor that influences the behavior of some species is the color of the culture tank; warranting the need to use tanks with a physical environment suitable for the species to be cultivated. Currently, striped bass are produced in tank-based hatcheries to be socked in sea cages for growout in Baja California. Thus, there is interest in improving their growth rate and feed efficiency under laboratory conditions. Therefore, the objective of this research was to evaluate the effect of three stocking densities (high: 6.2 kg m-3, medium: 3.1 kg m-3 and low: 1.5 kg m-3) and two tank colors (light blue and black) on the biological performance (growth, survival, food utilization), somatic indices and fish stress using the concentration of cortisol and glucose in blood serum as response variables of juvenile striped bass cultured in seawater for nine weeks. The results showed that the organisms had greater growth in terms of final weight when they were cultured at the medium stocking density, regardless of tank color. Likewise, density had a significant effect on hepatosomatic and liposomatic indices, with a tendency to decrease as density increased. The color of the tank significantly influenced the food consumption (blues: 37.4 ± 1.9 g·fish-1; blacks: 35.9 ± 2.0 g·fish-1). The interaction of the factors influenced TCE, TCA and TEP. The concentrations of cortisol (81.8 ± 22.5 ng·ml-1) and glucose (83.2 ± 11.4 mg·100 ml-1) were similar in all treatments indicating low fish stress. In conclusion, it was possible to elucidate under which laboratory culture conditions the organisms were able to overcome the stress factors without compromising their growth and survival; reflected in better biological performance. A stocking density of 4.2 kg m-3 o 233 fish·m-3 for M. saxatilis juvenile reared in saltwater under laboratory culture conditions is recommended.
lobina rayada, densidad cultivo, color tanque, estrés, crecimiento striped bass, stocking density, tank color, stress, growth CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CIENCIAS AGRARIAS PECES Y FAUNA SILVESTRE PISCICULTURA PISCICULTURA
Propagación sexual y asexual de Brosimum alicastrum Swartz en Campeche, México
Sexual and asexual propagation of Brosimum alicastrum Swartz in Campeche, Mexico
Santillán Fernández Alberto Orlando Valentín Santiago Santes Ezequiel Espinosa ZULEMA GUADALUPE HUICAB PECH FRANCISCO ALFONSO LARQUE SAAVEDRA Jaime Bautista-Ortega (2022, [Artículo])
Brosimum alicastrum is a tree species in Mexico with wide potential for animal and human food, which is distributed naturally with no silvicultural management, so there is little information on the propagation methods of the species. The objective of this work was to analyze the scientific research published on B. alicastrum, through literature review to know the techniques that exist on its propagation. In addition, the quality of the seedling obtained by sexual propagation and asexual methods (cuttings, layers and grafts) was evaluated in the nursery, by means of experimental designs. 550 scientific articles on B. alicastrum were found, the disciplines where they were published were: Ecology (44.18%), Botany (13.27%), Forest Sciences (11.27%, of which 2.54% worked propagation in the nursery), Zoology (11.09%), Agriculture (9.64%), Anthropology (5.45%) and others (5.10%). Regarding the seed propagation method, the best seedling quality was associated with low porosity substrates (bush soil) and containers with large diameters (36 cm). In the case of asexual propagation, with the layering method when peat was used as the substrate 90% survival was obtained, and by lateral grafting technique 75% yield was found. Due to the little research that exists on the propagation of the species, it is recommended that the selection of the propagation technique is based on the purpose of the seedling; if it is required to shorten the seed production cycles of B. alicastrum the asexual techniques grafting and layering can be more efficient. © 2022 Universidad Politecnica Salesiana. All rights reserved.
RAMON SILVICULTURA VIVERO FORESTAL INJERTO ENRAIZAMIENTO DE ESTACAS ACODO AEREO BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOLOGÍA VEGETAL (BOTÁNICA) ECOLOGÍA VEGETAL ECOLOGÍA VEGETAL