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Non-autonomous Ginzburg-Landau solitons using the He-Li mapping method

MAXIMINO PEREZ MALDONADO Haret Codratian Rosu ELIZABETH FLORES GARDUÑO (2022, [Artículo])

"We find and discuss the non-autonomous soliton solutions in the case of variable nonlinearity and dispersion implied by the Ginzburg-Landau equation with variable coefficients. In this work we obtain non-autonomous Ginzburg-Landau solitons from the standard autonomous Ginzburg-Landau soliton solutions using a simplified version of the He-Li mapping. We find soliton pulses of both arbitrary and fixed amplitudes in terms of a function constrained by a single condition involving the nonlinearity and the dispersion of the medium. This is important because it can be used as a tool for the parametric manipulation of these non-autonomous solitons. "

Nonlinear Ginzburg-Landau Equation Non-Autonomous Solitons CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA FÍSICA

The spatial control of migrants on the Chihuahua border

EDGAR ABEL CASTRO (2023, [Artículo, Artículo])

This article tries to link the immigration policies of the United States and Mexico with the narrative developed by Michel Foucault. It shows how racism is the axis on which the State of biopower exercises its claims and its effects of power on bodies and on life. Thus, the current political rationality goes through the management of the living body of people, their health, and their spatiality. This principle extends to the homicidal function of the State. Two events that occurred on the Chihuahua border demonstrate this.

migrant control Foucault border racism migrante frontera racismo HUMANIDADES Y CIENCIAS DE LA CONDUCTA HUMANIDADES Y CIENCIAS DE LA CONDUCTA

Manual para la cría masiva de Neochetina spp utilizado en el control biológico de lirio acuático

MARICELA MARTINEZ JIMENEZ (2005, [Libro])

Tabla de contenido: Introducción -- Antecedentes: definición de control biológico; Control biológico de lirio acuático; Ciclo biológico y características del género Neochetina; Especificidad del género Neochetina; Principales patógenos del género Neochetina; Cuarentena de insectos para el control biológico de malezas acuáticas; Cría masiva de insectos -- Metodología: cría masina de Neochetina; Liberación de Neochetina; Monitoreo -- Literatura citada -- Anexo fotográfico.

Se describen las bases para el control biológico del lirio acuático, así como una metodología para la cría masiva de dos especies de gorgojos: Neochetina eichhorniae y Neochetina bruchi, utilizados en el control biológico de esta maleza.

Introducción -- Antecedentes: definición de control biológico; Control biológico de lirio acuático; Ciclo biológico y características del género Neochetina; Especificidad del género Neochetina; Principales patógenos del género Neochetina; Cuarentena de insectos para el control biológico de malezas acuáticas; Cría masiva de insectos -- Metodología: cría masina de Neochetina; Liberación de Neochetina; Monitoreo -- Literatura citada -- Anexo fotográfico.

Malezas acuáticas Control biológico BIOLOGÍA Y QUÍMICA

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

Hymenopteran parasitoid complex and fall armyworm: a case study in eastern India

Tapamay Dhar PRATEEK MADHAB BHATTACHARYA Mahesh Gathala Alison Laing (2024, [Artículo])

Fall armyworm (FAW), Spodoptera frugiperda (J.E. Smith) has significantly affected maize crop yields, production efficiency, and farmers’ incomes in the Indian Eastern Gangetic Plains region since it was first observed in India in 2018. A lack of awareness by maize growers of the appropriate selection, method, and timing of insecticide application not only creates a barrier to sustainable FAW control but also contributes to increased environmental pollution, reduced human health and increased production costs. We demonstrated that FAW inflicted the most damage in early whorl growth stage of maize, regardless of whether chemical insecticides were applied. FAW egg masses and larvae collected from maize fields in which no insecticides had been sprayed showed high parasitism rates by parasitoid wasps; in contrast fields that had been sprayed had much lower rates of parasitism on FAW. Ten hymenopteran parasitoids were observed in maize fields across the study region, suggesting a diversity of natural methods to suppress FAW in maize at different growth stages. These included two FAW egg parasitoids and eight FAW larval parasitoids. Microplitis manilae Ashmead was the most abundant FAW larval parasitoid species, and Telenomus cf. remus was the dominant FAW egg parasitoid species. Endemic FAW parasitoids such as those observed in this study have great potential as part of a sustainable, cost-effective agroecological management strategy, which can be integrated with other methods to achieve effective control of FAW.

CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA FALL ARMYWORMS MAIZE INSECTICIDES INSECT CONTROL

Control biológico del lirio acuático en México: primera experiencia exitosa con neoquetinos en distritos de riego: volumen I: distrito de riego 010 Culiacán-Humaya, Sinaloa, distrito de riego 074 Mocorito, Sinaloa, distrito de riego 018 colonias Yaquis, Sonora

OVIDIO CAMARENA MEDRANO (2013, [Libro])

Los objetivos de esta investigación han sido: documentar las experiencias en el control biológico del lirio acuático en la infraestructura de riego en seis distritos de riego de México; dejar constancia de la eficacia y eficiencia de los neoquetinos como agentes de control biológico del lirio; demostrar la factibilidad de mantener sin problema de lirio, en forma permanente, cualquier cuerpo de agua del país mediante estre control biológico; y sensibilizar a las autoridades, técnicos y productores sobre las bondades del control biológico del lirio acuático en nuestro país, principalmente en los distritos de riego.

Lirio acuático Distritos de riego Control biológico Sinaloa Sonora CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA

Unanswered questions and unquestioned answers: the challenges of crop residue retention and weed control in Conservation Agriculture systems of southern Africa

Christian Thierfelder Blessing Mhlanga Hambulo Ngoma Paswel Marenya Md Abdul Matin Adane Tufa (2024, [Artículo])

Production and utilization of crop residues as mulch and effective weed management are two central elements in the successful implementation of Conservation Agriculture (CA) systems in southern Africa. Yet, the challenges of crop residue availability for mulch or the difficulties in managing weed proliferation in CA systems are bigger than a micro-level focus on weeds and crop residues themselves. The bottlenecks are symptoms of broader systemic complications that cannot be resolved without appreciating the interactions between the current scientific understanding of CA and its application in smallholder systems, private incentives, social norms, institutions, and government policy. In this paper, we elucidate a series of areas that represent some unquestioned answers about chemical weed control and unanswered questions about how to maintain groundcover demanding more research along the natural and social sciences continuum. In some communities, traditional rules that allow free-range grazing of livestock after harvesting present a barrier in surface crop residue management. On the other hand, many of the communities either burn, remove, or incorporate the residues into the soil thus hindering the near-permanent soil cover required in CA systems. The lack of soil cover also means that weed management through soil mulch is unachievable. Herbicides are often a successful stopgap solution to weed control, but they are costly, and most farmers do not use them as recommended, which reduces efficacy. Besides, the use of herbicides can cause environmental hazards and may affect human health. Here, we suggest further assessment of the manipulation of crop competition, the use of vigorously growing cover crops, exploration of allelopathy, and use of microorganisms in managing weeds and reducing seed production to deplete the soil weed seed bank. We also suggest in situ production of plant biomass, use of unpalatable species for mulch generation and change of grazing by-laws towards a holistic management of pastures to reduce the competition for crop residues. However, these depend on the socio-economic status dynamics at farmer and community level.

CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA INTEGRATED CROP-LIVESTOCK SYSTEMS CROP RESIDUES ZERO TILLAGE SOCIAL NORMS SUSTAINABLE INTENSIFICATION WEED CONTROL