Sustainable Intensification in Crop-Livestock Systems

Extensive livestock production is the main animal source food system in the Pampas and Campos sub-regions in South America. Beef cattle and sheep convert forage biomass that humans cannot eat into nutrient-dense human-edible foods (meat and milk) and valuable co-products (wool). However, diverse global pressures are acting on Pampas systems including increasing demand for protein sources (food security), climate change, environmental footprint, and competition for land. The integration of small areas of pasture-crop rotations is an alternative for increasing efficiency and sustainable intensification of agroecosystems based on natural grasslands. Rotations led by improved pastures increase the carrying capacity and productivity of traditional Pampas systems, and include crop production (soybean, rice) as an opportunity for farm diversification and resilience. Therefore, mixed crop-livestock systems can feed more people in terms of calories and protein than what is possible with specialized systems. The higher carrying capacity in the area under the rotation may allow less intensive grazing management in larger areas of native grasslands reducing threats to biodiversity. Some of the integrated management practices in crop-livestock systems are perennial pastures to mitigate soil organic carbon losses during cropping, biological nitrogen fixation by legumes, grazing cover crops, crop residue grazing, dual-purpose crops, and harvesting grain and hay for livestock feed. Also, complementary crop and livestock production systems facilitate more efficient nutrient cycling and self-sufficient systems promoting the circular economy concept as a strategic approach toward system sustainability. Key to understanding the potential of mixed crop-livestock systems are productive, environmental, economic, and social factors that determine their performance, as well as trade-offs among them. Development, implementation, maintenance, and analysis of long-term crop-livestock platforms research provides science-based information to address complex biological systems, and to implement innovative public policies at national scale to regulate soil use and to prevent non-sustainable agricultural practices

Síntesis de bajo impacto ambiental de moléculas análogas a monastrol y nifedipina a través de reacciones multicomponente empleando catalizadores compuestos de heteropoliácidos soportados en óxidos mesoporosos

En la búsqueda de moléculas biológicamente activas, la familia de heterociclos formada por las pirimidinas y sus derivados ha generado gran interés a nivel académico e industrial. Las limitaciones de métodos convencionales, ha conllevado a desarrollar mejores modelos en relación a, selectividad, procedimientos y equipos sencillos, ahorro de energía y tiempo, economía atómica e impacto ambiental

Síntesis de materiales compuestos tio2-tpa/biochar vía ultrasonido y sol-gel para la degradación de ibuprofeno y diclofenaco

En este trabajo, se sintetizó material residual de biomasa (cáscaras de semillas de girasol -CSG) mediante activación química y térmica para obtener carbón activado (AC) y se utilizó como soporte de TiO2 modificado con 30% de ácido tungstofosfórico (TPA) para formar fotocatalizadores compuestos para potenciar la adsorción y fotodescomposición de productos farmacéuticos y productos de cuidado personal (PPCPc)

Aplicación de Fotocatalizadores Obtenidos a partir de Ácido Tungstofosfórico sobre NH4ZSM5 en Remediación de Aguas Contaminadas

Se prepararon materiales a partir de la inmovilización de ácido tungstofosfórico sobre zeolita NH4ZSM5 mediante impregnación húmeda para ser aplicados en la degradación de moléculas representativas de contaminantes presentes en efluentes empleando fotocatálisis heterogénea. La concentración de ácido tunstofosfórico incorporada fue de 10 y 30% p/p en el sólido obtenido. Los materiales se caracterizaron mediante diferentes técnicas fisicoquímicas. El área superficial disminuyó respecto de la matriz sin modificar como resultado de bloqueo de los poros de la zeolita. Los patrones de difracción de rayos X de las muestras modificadas presentaron los picos característicos de zeolita NH4ZSM5 y un conjunto de picos adicionales asignados a la presencia de la sal (NH4)3[PW12O40]. Además, las muestras exhibieron valores de band gap similares a los reportados para los semiconductores más estudiados. Se obtuvieron catalizadores con elevada actividad fotocatalítica en las moléculas de estudio

Experimental ‘Jet Lag’ Inhibits Adult Neurogenesis and Produces Long-Term Cognitive Deficits in Female Hamsters

Background: Circadian disruptions through frequent transmeridian travel, rotating shift work, and poor sleep hygiene are associated with an array of physical and mental health maladies, including marked deficits in human cognitive function. Despite anecdotal and correlational reports suggesting a negative impact of circadian disruptions on brain function, this possibility has not been experimentally examined. Methodology/Principal Findings: In the present study, we investigated whether experimental ‘jet lag ’ (i.e., phase advances of the light:dark cycle) negatively impacts learning and memory and whether any deficits observed are associated with reductions in hippocampal cell proliferation and neurogenesis. Because insults to circadian timing alter circulating glucocorticoid and sex steroid concentrations, both of which influence neurogenesis and learning/memory, we assessed the contribution of these endocrine factors to any observed alterations. Circadian disruption resulted in pronounced deficits in learning and memory paralleled by marked reductions in hippocampal cell proliferation and neurogenesis. Significantly, deficits in hippocampal-dependent learning and memory were not only seen during the period of the circadian disruption, but also persisted well after the cessation of jet lag, suggesting long-lasting negative consequences on brain function. Conclusions/Significance: Together, these findings support the view that circadian disruptions suppress hippocampal neurogenesis via a glucocorticoid-independent mechanism, imposing pronounced and persistent impairments on learnin

Effects of circadian disruption on physiology and pathology: from bench to clinic (and back)

Nested within the hypothalamus, the suprachiasmatic nuclei (SCN) represent a central biological clock that regulates daily and circadian (i.e., close to 24 h) rhythms in mammals. Besides the SCN, a number of peripheral oscillators throughout the body control local rhythms and are usually kept in pace by the central clock. In order to represent an adaptive value, circadian rhythms must be entrained by environmental signals or zeitgebers, the main one being the daily light?dark (LD) cycle. The SCN adopt a stable phase relationship with the LD cycle that, when challenged, results in abrupt or chronic changes in overt rhythms and, in turn, in physiological, behavioral, and metabolic variables. Changes in entrainment, both acute and chronic, may have severe consequences in human performance and pathological outcome. Indeed, animal models of desynchronization have become a useful tool to understand such changes and to evaluate potential treatments in human subjects. Here we review a number of alterations in circadian entrainment, including jet lag, social jet lag (i.e., desynchronization between body rhythms and normal time schedules), shift work, and exposure to nocturnal light, both in human subjects and in laboratory animals. Finally, we focus on the health consequences related to circadian/entrainment disorders and propose a number of approaches for the management of circadian desynchronization.Fil: Chiesa, Juan José. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Duhart, José Manuel. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Casiraghi, Leandro Pablo. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Paladino, Natalia. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Bussi, Ivana Leda. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Golombek, Diego Andrés. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin