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Perfil epidemiológico y características clínicas de la escleritis en una población del noreste de México

YOLANDA MACIAS RODRIGUEZ (2022, [Artículo])

La epiescleritis (ESC) y escleritis (SC) son enfermedades que se caracterizan por causar inflamación de la capa externa fibrosa del globo ocular, la esclera y epiesclera. Estos padecimientos fueron descritos desde el siglo XIX y el Dr. Watson proporcionó la clasificación clínica que se usa para ordenarlas en sus diferentes subtipos. La etiología de las ESC y SC puede ser idiopática o asociada a causas específicas, como enfermedades autoinmunes, traumatismos, cirugías o infecciones. En diversas poblaciones del mundo se han reportado previamente las características de las ESC y SC. Sin embargo, en la población mexicana solo existen reportes de casos de presentaciones inusuales de ESC y SC y una sola serie reportando las características de la SC. Por lo anterior, se decidió llevar a cabo el presente estudio para expandir el conocimiento acerca de las características de la ESC y SC en la población mexicana. Se realizó un estudio retrospectivo y observacional. El diseño metodológico corresponde a una serie de casos. Se incluyeron pacientes con diagnóstico de ESC y SC, que hubieran firmado el consentimiento informado para participación en investigación clínica. Se analizaron los expedientes físicos y electrónicos de los pacientes que cumplieran con los criterios de inclusión, se tomó la información correspondiente a las variables previamente establecidas y se vació en una hoja de Microsoft Excel y posteriormente se analizaron estadísticamente con el programa SPSS (IBM). Se encontraron y analizaron 55 casos de ESC y 130 casos de SC. En ambos grupos hubo una predominancia del sexo femenino y la edad media fue mayor en pacientes con SC que en ESC (52.26 vs. 44.78 años). El tipo más común de ESC fue la simple y en SC la anterior difusa. La SC posterior fue el subtipo menos frecuente. La etiología más frecuente en ESC y SC fue la idiopática, y la segunda en frecuencia fue la espondiloartropatía asociada al haplotipo HLA B27 y la artritis reumatoide respectivamente. Los motivos de consulta más frecuente fueron ojo rojo solamente y ojo rojo doloroso. Los síntomas más comúnmente descritos por los pacientes con ESC y SC fueron ojo rojo, sensación de cuerpo extraño, dolor, lagrimeo y visión borrosa. Asimismo, los datos clínicos más comúnmente encontrados en pacientes con ESC y SC fueron la ingurgitción de los plexos conjuntivales y epiesclerales, queratopatía punteada superficial y queratitis ulcerativa periférica. La agudeza visual promedio fue buena tanto en ESC como en SC, siendo de 20/25 y 20/30 respectivamente. Para el análisis de tratamiento y recurrencias, se consideraron a los pacientes con un seguimiento mayor a una consulta, consistiendo estos últimos en 35 ESC y 108 SC. En la ESC, 91.4% de los pacientes fueron tratados con un AINE oral, 57.1% con esteroide tópico y 5.7% con AINE tópico. En SC, 76.9% usaron un AINE oral, 62% un esteroide oral, 50% un esteroide tópico y 52.7% un agente imnunosupresor. 29.6% de los pacientes con SC tuvieron una recurrencia. Al comparar la presente serie con las series de ESC y SC reportadas previamente en la literatura se encontró una considerable cantidad de similitudes, como la predominancia del sexo femenino, la media de edad, la incidencia estimada, los síntomas y signos, el tratamiento empleado y la cantidad de recurrencias y su asociación a una edad menor. Debido a todos lo anterior, se concluyó que la presentación de las ESC y SC en la población mexicana es similar a la presentación en otras poblaciones del mundo, previamente reportadas.

Especialidad en Oftalmología

MEDICINA Y CIENCIAS DE LA SALUD CIENCIAS MÉDICAS CIENCIAS CLÍNICAS OFTALMOLOGÍA

Economics of crop residue management

Vijesh Krishna Maxwell Mkondiwa (2023, [Artículo])

More than five billion metric tons of agricultural residues are produced annually worldwide. Despite having multiple uses and significant potential to augment crop and livestock production, a large share of crop residues is burned, especially in Asian countries. This unsustainable practice causes tremendous air pollution and health hazards while restricting soil nutrient recycling. In this review, we examine the economic rationale for unsustainable residue management. The sustainability of residue utilization is determined by several economic factors, such as local demand for and quantity of residue production, development and dissemination of technologies to absorb excess residue, and market and policy instruments to internalize the social costs of residue burning. The intervention strategy to ensure sustainable residue management depends on public awareness of the private and societal costs of open residue burning.

Crop Biomass Residue Burning Environmental Effects CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CROPS BIOMASS RESIDUES ENVIRONMENTAL IMPACT CLIMATE CHANGE SMALLHOLDERS TECHNOLOGY ADOPTION

Application of ammonium to a N limited arable soil enriches a succession of bacteria typically found in the rhizosphere

Yendi Navarro-Noya Marco Luna_Guido Nele Verhulst Bram Govaerts Luc Dendooven (2022, [Artículo])

Crop residue management and tillage are known to affect the soil bacterial community, but when and which bacterial groups are enriched by application of ammonium in soil under different agricultural practices from a semi-arid ecosystem is still poorly understood. Soil was sampled from a long-term agronomic experiment with conventional tilled beds and crop residue retention (CT treatment), permanent beds with crop residue burned (PBB treatment) or retained (PBC) left unfertilized or fertilized with 300 kg urea-N ha-1 and cultivated with wheat (Triticum durum L.)/maize (Zea mays L.) rotation. Soil samples, fertilized or unfertilized, were amended or not (control) with a solution of (NH4)2SO4 (300 kg N ha-1) and were incubated aerobically at 25 ± 2 °C for 56 days, while CO2 emission, mineral N and the bacterial community were monitored. Application of NH4+ significantly increased the C mineralization independent of tillage-residue management or N fertilizer. Oxidation of NH4+ and NO2- was faster in the fertilized soil than in the unfertilized soil. The relative abundance of Nitrosovibrio, the sole ammonium oxidizer detected, was higher in the fertilized than in the unfertilized soil; and similarly, that of Nitrospira, the sole nitrite oxidizer. Application of NH4+ enriched Pseudomonas, Flavisolibacter, Enterobacter and Pseudoxanthomonas in the first week and Rheinheimera, Acinetobacter and Achromobacter between day 7 and 28. The application of ammonium to a soil cultivated with wheat and maize enriched a sequence of bacterial genera characterized as rhizospheric and/or endophytic independent of the application of urea, retention or burning of the crop residue, or tillage.

CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA AMMONIUM CROP RESIDUES WHEAT MAIZE TILLAGE SOIL

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

The fate of rice crop residues and context-dependent greenhouse gas emissions: Model-based insights from Eastern India

Sonam Sherpa virender kumar Andrew Mcdonald (2024, [Artículo])

Crop residue burning is a common practice in many parts of the world that causes air pollution and greenhouse gas (GHG) emissions. Regenerative practices that return residues to the soil offer a ‘no burn’ pathway for addressing air pollution while building soil organic carbon (SOC). Nevertheless, GHG emissions in rice-based agricultural systems are complex and difficult to anticipate, particularly in production contexts with highly variable hydrologic conditions. Here we predict long-term net GHG fluxes for four rice residue management strategies in the context of rice-wheat cropping systems in Eastern India: burning, soil incorporation, livestock fodder, and biochar. Estimations were based on a combination of Tier 1, 2, and 3 modelling approaches, including 100-year DNDC simulations across three representative soil hydrologic categories (i.e., dry, median, and wet). Overall, residue burning resulted in total direct GHG fluxes of 2.5, 6.1, and 8.7 Mg CO2-e in the dry, median, and wet hydrologic categories, respectively. Relative to emissions from burning (positive values indicate an increase) for the same dry to wet hydrologic categories, soil incorporation resulted in a −0.2, 1.8, or 3.1 Mg CO2-e change in emissions whereas use of residues for livestock fodder increased emissions by 2.0, 2.1, or 2.3 Mg CO2-e. Biochar reduced emissions relative to burning by 2.9 Mg CO2-e in all hydrologic categories. This study showed that the production environment has a controlling effect on methane and, therefore, net GHG balance. For example, wetter sites had 2.8–4.0 times greater CH4 emissions, on average, than dry sites when rice residues were returned to the soil. To effectively mitigate burning without undermining climate change mitigation goals, our results suggest that geographically-target approaches should be used in the rice-based systems of Eastern India to incentivize the adoption of regenerative ‘no burn’ residue management practices.

Soil Carbon Rice Residue Burning Life Cycle Assessment CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA SOIL CARBON RICE LIFE CYCLE GREENHOUSE GASES CLIMATE CHANGE

Addressing agricultural labour issues is key to biodiversity-smart farming

Thomas Daum Frédéric Baudron Matin Qaim Ingo Grass (2023, [Artículo])

There is an urgent need for agricultural development strategies that reconcile agricultural production and biodiversity conservation. This is especially true in the Global South where population growth is rapid and much of the world's remaining biodiversity is located. Combining conceptual thoughts with empirical insights from case studies in Indonesia and Ethiopia, we argue that such strategies will have to pay more attention to agricultural labour dynamics. Farmers have a strong motivation to reduce the heavy toil associated with farming by adopting technologies that save labour but can negatively affect biodiversity. Labour constraints can also prevent farmers from adopting technologies that improve biodiversity but increase labour intensity. Without explicitly accounting for labour issues, conservation efforts can hardly be successful. We hence highlight the need for biodiversity-smart agriculture, that is farming practices or systems that reconcile biodiversity with land and labour productivity. Our empirical insights suggest that technological and institutional options to reconcile farmers' socio-economic goals and biodiversity conservation exist but that more needs to be done to implement such options at scale.

Land Sharing Trade-Offs CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA AGRICULTURAL DEVELOPMENT BIODIVERSITY CONSERVATION LABOUR SUSTAINABILITY

Influencia de las fases lunares en fertilidad, tasa de preñez y partos de vacas mestizas en el trópico seco.

CANUTO MUÑOZ GARCIA ROSENDO CUICAS HUERTA JUAN GONZALEZ MALDONADO EFREN ESTRADA PAQUI ISIDRO JAUREGUI PLATA JULIO CESAR GOMEZ VARGAS (2023, [Artículo])

There is speculation about moon phases influencing animal reproductive performance. A study was carried out to shed light on the influence of moon phases on estrus presentation, pregnancy rate, calving presentation, and offspring sex in cows from the Mexican dry tropical region. The reproductive data of 580 crossbred cows from 2010 to 2021 was organized according to reproductive events (estrus presentation, gestation, calving presentation, and offspring sex) occurrence during moon phases (new moon, first quarter, full moon, and last quarter). The data were analyzed by Chi-squared test and logistic regression. The full moon reduced the estrus presentation (p0.05). It is concluded that the full moon reduces estrus presentation in crossbred cows. Moon phases do not influence the gestation, calving presentation, and offspring sex.

estrus calving offspring sex CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CIENCIAS AGRARIAS CIENCIAS VETERINARIAS FISIOLOGÍA ANIMAL