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Biosorption deals with absorbing or removing contaminants present in air, soil or water by means of using living or non-living biomass. In this project, a series of panels made of hay bound by Pleurotus ostreatus hyphae were constructed with the objective of characterizing the creation of the material and proposing an alternative to filtering contaminated water. The material was constructed efficiently, and the qualitative density of the mycelium was high in all studied replicates. Despite the material being hydrophobic, water absorption was documented – more than 200% of the original weight – and compared with previous literature. In this manner, the material constructed herein could be a candidate for treating water for human consumption. Future research on the subject is necessary. 

Climate and market shocks impact on the livelihood strategies of families in Altiplano communities. A household survey of 360 families in the Altiplano sheds light how families participate in markets, cope with climate and market shocks, and their feelings of control over these events. Theory proposes that the higher levels of capitals and climate resilient activities will result in a greater sense of control and therefore lower sense of dread. Cluster analysis identified three groups by wealth and life cycle characteristics in each region, as well as clear differences in income, assets, and market production activities between and within regions. Coping strategies in region facing warming and drying trends has focused on loss of assets, such as sales of animals. While in both regions there is diversity of income sources, the major source of diversity in Ancoraimes is crop varieties. While in both regions climatic shocks have had a negative impact on production, this has been experienced in Ancoraimes by 99 to 100 percent of the families, which has implications in terms of coping mechanism that rely on community networks. The other region has also experienced high rates of production shocks, from 71 to 92 percent of household members in each group. Strategies to diversify to climate resilient activities have resulted in increased off farm activities, mostly migration, in the lower income, lower asset region, while the greater assets in livestock, which face a more stable market and ability to withstand climate shocks presents a bifurcated response. Comparison between groups identified in the clusters for each region found no significant differences between groups on climate shock and climate change perceptions, in both regions. The rating on the risk of climate shock hazards at the household level was above 4 in a scale of 1-5 where 4 meant a very high threat and 5 an extreme threat. Umala households ratings were higher for the shocks than for change in climate with an average of 3.79 for the latter, while in Ancoraimes most of the risks were rated from 3.70 to 3.92, with the exception of climate change that was around 4. Overall though, in both regions climate hazard perceptions are high. Market risks are also considered a threat but rated lower than climate. Dread of losing outside networks of support was ranked high by elderly men and women, as well as the change in climate, in Umala, with no differences in Ancoraimes, but higher rates of dread overall do to the significance of this income in their livelihood strategies. Finding to date are consistent with theory, in that the dread, a reflection of the coping or lack of coping mechanisms, is higher in terms of markets for livestock in Umala, and higher in terms of loss of remittances from family members in Ancoraimes. The study finds that coping mechanism are based on individual household strategies, rather than community or institutions. LTRA-4 (Practices and Strategies for Vulnerable Agro-Ecosystems)

Introducción. La biomasa lignocelulósica que proviene de residuos agrícolas, cultivos dedicados a la dendroenergía, residuos biológicos lignocelulósicos como subproductos de alimentos, sobras de cocina de hogares, restaurantes y locales comerciales, así como algas cultivadas, pueden ser considerados materias primas para el desarrollo de la bioeconomía. Dado que su composición se basa mayoritariamente en celulosa, hemicelulosa y lignina; materiales de base para la producción de diversos productos de valor agregado a partir de bloques de bioconstrucción en procesos integrados de bio-refinería. Objetivo. Establecer la importancia del uso de la biomasa como materia prima para su incorporación en los modelos de economía circular en los procesos de biorrefinería, tales como consideraciones de manejo de biomasa y pretratamiento de biomasa, el potencial intrínseco para la obtención de sustancias de valor comercial en función de la cadena de carbono. Desarrollo. Aproximadamente el 90 % de la materia seca lignocelulósica consiste en celulosa (30-60 %), hemicelulosa (20-40 %) y lignina (10-25 %) interrelacionados en una heteromatriz, mientras que el resto consiste en cenizas y extractos. Se estima que el potencial de generación de energía a base de biomasa oscila en Costa Rica cerca a los 600 MW y se han identificado proyectos activos que generan cerca de 122 MW. Conclusión. El aprovechamiento de la biomasa es un elemento importante para ser incorporado en la producción de bioenergía y desarrollo de una industria química renovable que conlleve a la consecución de objetivos enmarcados en el desarrollo de un modelo bio-económico, donde Costa Rica ha iniciado su incursión paralela al avance del siglo XXI. Introduction. The lignocellulosic biomass that comes from agricultural residues, crops dedicated to wood energy, lignocellulosic biological residues as food by-products, kitchen scraps from homes, restaurants, and commercial premises, as well as cultivated algae, can be considered raw materials for the development of the bioeconomy. Since its composition is mainly based on cellulose, hemicellulose, and lignin; they can be used to produce various value-added products from bio-construction blocks in integrated bio-refinery processes. Objective. To stablish the importance of using biomass as a raw material for its incorporation in circular economy models in biorefinery processes, such as considerations of biomass management and pretreatment of biomass, the intrinsic potential for obtaining substances of commercial value depending on the carbon chain. Development. Approximately 90 % of lignocellulosic dry matter consists of cellulose (30-60 %), hemicellulose (20-40 %), and lignin (10-25 %) interrelated in a heteromatrix, while the remainder consists of ash and extracts. It is estimated that the biomass-based power generation potential in Costa Rica ranges close to 600 MW and active projects that generate about 122 MW have been identified. Conclusion. The use of biomass is an important element to be incorporated into the production of bioenergy and the development of a renewable chemical industry that leads to the achievement of objectives framed in the development of a bio-economic model, where Costa Rica has begun its parallel incursion to the advance of the 21st century.

De acuerdo al Índice de Necesidades Básicas Insatisfechas (NBI), en la microcuenca del río Illangama, alrededor del 76% de la población es pobre y sus ingresos están entre US$120 y 160 por mes, aún después de adoptar sistemas complejos con un alto potencial de producción. El más importante de ellos es el sistema papa-leche que aporta la mayor proporción de ingresos familiares y garantiza su seguridad alimentaria. Desde este punto de vista, se realizó un análisis de la viabilidad socio-económica y ambiental del sistema con el propósito de establecer su eficiencia y flexibilidad bajo nuevas condiciones. Este análisis se basa en la información compilada de diferentes fuentes, niveles y escalas, mediante estudios de campo, investigación experimental y observación de parcelas de productores. Los resultados evidencian que el sistema tiene el más alto potencial de productividad en el área y es viable adoptar porque incrementa la producción y los ingresos. Representa la mejor opción debido a que los productores disponen de los medios de producción y mano de obra familiar, lo cual permitirá que el sistema sea sostenible. Desde el punto de vista ambiental, si el sistema es manejado adecuadamente con la implementación de alternativas tecnológicas, amigables con el ambiente, detendría el avance de la frontera agrícola hacia áreas de páramo. El sistema es una opción que los gobiernos locales deberían impulsar para preservar el ecosistema páramo. (Resumen de autores) Published version LTRA-3 (Watershed-based NRM for Small-scale Agriculture)

Sweeping changes are beginning to transform energy scenarios around the world. The gas revolution, a renaissance in petroleum technology and exploration, and a chaotic but powerful movement toward the goal of low-carbon economies are three of the principal energy trends currently interacting with structural changes in the geo-economics of the Atlantic world to present new perspectives and opportunitiesfor the diverse actors in the ‘Atlantic Basin’. This article explores how changes in the energy landscape are contributing to a reassessment of the strategic horizon. The potential impacts of the shale revolution, deep-offshore oil, biofuels and other modern renewable energies on the geopolitics of the Atlantic Basin will be assessed, and the hypothesis that an Atlantic Basin energy system is now taking shape will be evaluated, along with an analysis of anticipated impacts.

La radiación ultravioleta (UV) contribuye relativamente con poca energía al espectro solar. Sin embargo, es importante, porque biológicamente es muy activa. El objetivo de este trabajo es valorar los niveles máximos de radiación solar UV sobre un plano horizontal, utilizando mapas diseñados para el territorio de Costa Rica, creados por el software Surfer 8. Los datos que fueron usados en la creación de los mapas fueron predichos al mediodía local en ochenta y tres localidades esparcidas por el territorio nacional con un modelo atmosférico espectral, el cual es físicamente establecido. El modelo emplea comodatos d entrada necesarios: la fecha y hora, el lugar identificado por la latitud, la longitud y la altura del terreno sobre el nivel del mar, el valor de la columna vertical del ozono, el albedo superficial y los parámetros de turbiedad atmosférica. La estimación y los parámetros de turbiedad atmosférica. La estimación difiere en un 3% de las mediciones hechas in situ, lo que está de acuerdo con los datos experimentales. El modelo utilizada, en la estimación de los datos de radiación UV, condiciones de cielo claro, que es la condición donde se obtiene la máxima energía posible en cada localidad. Lo cual tiene su importancia fundamental a la hora de valorar los efectos nocivos para la salud humana, ya que puede ocasionar la máxima intensidad posible en esta importante banda del espectro solar. Entre los resultados más destacados puede mencionarse un incremento mayor del 23% en la radiación UV con la altitud, obteniendo los cerros y las montañas los índices más altos y los lugares ubicados al nivel del mar y sobre la costa los índices más bajos. Análisis de variación anual revelan un incremento mayor al 27% entre el mes de menor radiación UV (diciembre) y el mes de mayor radiación UV (abril). Este tema es de especial interés, debido al creciente número de personas que se desplazan durante diferentes épocas del año a altitudes mayores de los 2000 m de altura, en actividades relativas al turismo y al trabajo. En este caso, estas personas reciben importantes incrementos en los niveles de radiación sola UV en condiciones de cielos despejados. Ultraviolet radiation (UV) contributes relatively little to the solar spectrum. However it is very important because it is biological very active. The aim of this work is to evaluate the levels of ultraviolet solar radiation (UV) using solar radiation maps designed for the territory of Costa Rica created with the software Surfer 8. The data of UV radiation – utilized in the creation of the maps – were predicted in eighty-three geographical locations by an atmospheric spectral model, which is physically established, this model utilizes as necessary input data: the date and hour, identifying place by the latitude, length and height of the land above sea level, the value of the vertical column of the ozone, the superficial albedo and the atmospheric turbidity parameters. The estimation differs in a 3% with the experimentation data made in situ. The model estimate ultraviolet radiation under clear skies conditions; this is the maximum possible energy which is obtained in each locality. This is important at the moment to evaluate the harmful effects for the human health can cause the maximum intensity in this important band of the solar spectrum. Among the most noticeable results can be mentioned an increase of 23% with the altitudes, among the lower places (sea level) and higher places (hills and mountains). It was also found an increment greater that 27% between the months of fewer solar radiation (December) and greater solar radiation (Apri). This theme is of special interest due to the growing number of people that displace during different times of the year to altitudes greater than 2000 m in activities relating to the tourism, recreation and work. In this case these people receive important increments in the levels of ultraviolet solar radiation in clear sky conditions.

In this article, it was reviewed as the postpartum negative energy balance (NEB) affects the health and the reproductive efficiency of water buffaloes. The increase in the world buffalo population has been accompanied by an improvement in the milk yield per lactation and this could be causing negative consequences for health and reproductive efficiency, although there are still few studies about this relationship. Higher milk yield without the corresponding increase in the dry matter and energy intake can intensify the NEB, increasing weight and body condition loss, and this implies a decrease in glucose, insulin and insulin-like growth factor 1 (IGF-1) levels and the increases of non-esterified fatty acids (NEFAs) and β-hydroxybutyrate (BHB). This scenario may imply a greater susceptibility to diseases such as placental retention, endometritis, metritis and mastitis, as well as a longer period of anestrus, lower fertility and the lengthening of the interval to conception. To solve this situation, it is necessary to guarantee a good body condition at calving, and a high dry matter intake that allows reducing weight loss and body condition and different management, feeding and genetic alternatives are proposed.

UNIVERSIDAD, CIENCIA y TECNOLOGÍA Vol. 25, Nº 111 Diciembre 2021(pp. 212-225) ; En este trabajo se presentan las curvas de coeficientes de sustentación y arrastre en función del ángulo de ataque, para los perfiles NACA0012, S809 y SG6043 en condiciones de flujo turbulento. El objetivo es identificar el perfil aerodinámico que tiene mejor rendimiento en condiciones de relevancia para las turbinas eólicas de pequeña escala. El análisis se realizó mediante simulación utilizando OpenFOAM. En el caso del perfil NACA0012 se encuentra que su desempeño es poco sensible a cambios en la turbulencia y en el número de Reynolds. La respuesta del perfil S809 es de aumentar tanto el arrastre como la sustentación al aumentar la turbulencia. El desempeño del perfil SG6043 resulta ser el más conveniente en flujo turbulento pues las curvas de sustentación en su mayoría aumentan al aumentar la turbulencia. Las curvas que se reportan aquí son inéditas y no se encuentra en la literatura. ; This work presents the lift and drag coefficient curves, as functions of the angle of attack, for the NACA0012, S809 and SG6043 airfoils in turbulent flow conditions. The objective is to identify the airfoil with the best aerodynamic performance under conditions that are descriptive of small scale wind turbine. With the use of OpenFOAM, an analysis was done by numerical simulation. In the case of the NACA0012 airfoil, it was found that the performance is insensitive to the changes in turbulence and the Reynold number. The aerodynamic response of the S809 airfoil is to increase both the drag and lift as the turbulence increases. The SG6043 airfoil responds the best out of the three in turbulent flow, given that the lift curves mostly increase with the turbulence. The curves reported in this work are new and not found in previous literature.

The amount of energy and food consumed in Puerto Rico is more indicative of a developed nation than one than is underdeveloped. All the energy consumed in Puerto Rico is from fossil fuels, while the agricultural sector marginally provides the needs of the consumer. In addition, the animal production sectors rely exclusively on imported feedstock for the preparation of feeds. There is a potential to develop an ethanol industry based initially on sugarcane, as the main feedstock and then turn to biomass from energy cane and or organic solid waste in the future. In order to move to the second generation of ethanol production, the cellulosic ethanol industry has to become economically viable. A limiting factor in the use of sugarcane is that only 40,000 ha are currently available to grow this crop. Potentially, Puerto Rico can produce 200 million liters of ethanol on this area which could substitute 5% of the gasoline that was consumed in 2007. On the other hand, biomass could be obtained from bagasse, energy cane, and from 1.3 metric tons of organic solid waste (food and yard waste) produced annually on the island. This strategy can provide a relief to decreasing the amounts of organic solid waste that end up in the landfills.