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Application of artificial neural networks for rapid flash calculations
Compositional reservoir simulation is widely used as an important tool for optimization of enhanced oil recovery processes. In compositional reservoir simulation, flash calculations are performed to solve for phase properties and amounts for each grid-block and each time step by use of a cubic equation of state (EOS). EOS flash calculation is one of the most time-consuming operations during compositional reservoir simulation. There has been a critical need for more efficient EOS flash for practical compositional reservoir simulation.
The central idea tested in this thesis is to use artificial neural networks (ANNs) to replace the most fundamental, but time-consuming portion of EOS flash; that is, the evaluation of fugacity coefficients. ANNs are used for efficient feedforward approximation of the EOS fugacity coefficient function with a series of weights, bias, and activation functions. A set of weights and bias is found by using an algorithm that minimizes the mean squared error between the predicted and real values. This type of approximation is called supervised learning in machine learning applications. The thermodynamic model used is the Peng – Robinson equation of state with the van der Waals mixing rules and solved by the successive substitution algorithm for flash calculations.
The implementation of the ANN-based fugacity coefficient function is straightforward because it only replaces the EOS-based fugacity coefficient in conventional flash calculation algorithms. Once an ANN-based fugacity coefficient function is built based on a cubic EOS, the EOS is required only when phase densities are calculated, usually at the final convergence. That is, ANN-based flash does not use an EOS during the iterative solution. We show comparisons between the conventional EOS flash calculations and the ANN flash calculations in terms of computational efficiency. Use of ANN flash can reduce on average 89.83% of the time needed by the conventional EOS flash for the cases studied in this thesis.Petroleum and Geosystems Engineerin
Canales y márgenes de comercialización de caprinos en Tejupilco y Amatepec, estado de México
Con el objetivo de analizar los canales y márgenes de comercialización de la carne de caprino, se realizó una investigación en los municipios de Tejupilco y Amatepec, Estado de México durante 2004-2005. Se determinó el canal de comercialización más utilizado por los agentes participantes de dicho mercado y se calcularon los márgenes absolutos y relativos, a través de la obtención de sus valores equivalentes y de los costos y ganancias de cada agente participante. De 133 productores entrevistados, 96.5% realiza la venta en pie. El productor obtuvo 46.5% del precio real que pagó el consumidor final por kilogramo de carne cruda y el intermediario 53.5%. Considerando la birria como producto final, el productor alcanzó 20.42% de las ganancias de todo el proceso y los intermediarios 79.58%; los birrieros obtuvieron la mayor parte (79.58%) del margen total de comercialización. El canal de comercialización más común fue productor, acopiador regional, birriero y consumidor final. Se concluye que el birriero obtuvo las mayores relaciones beneficio costo (8.86 y 8.61)
Anthelmintic effects of Salix babylonica L. and Leucaena leucocephala Lam. extracts in growing lambs
In Mexico, small ruminant production has important social and economic functions, especially for small rural farmers who rely on these animals as a source of food and income. Production efficiency of ruminants has been limited by nutritional and sanitary problems with helminth infections being one of the major health conditions affecting humans and livestock. Exposure to nematode parasites depends on the husbandry system under which livestock are raised. In situations where Mexican farmers are almost entirely dependent on grazing, exposure to nematode larvae is continuous throughout the year. Gastrointestinal nematode parasitism is a major cause of sheep and goat mortality in tropical Mexico (Canul-Ku et al. 2012) and other tropical countries (Carvalho et al. 2012). The impacts of gastrointestinal nematode parasitism in practical systems has stimulated research into alternative medications, such as medicinal plants or tree leaf extracts, which are used in ruminants, donkeys, camels, and humans (Wabo-Pone et al. 2009; Carvalho et al. 2012).Twenty Katahdin×Pelibuey crossbreed male lambs, 3 to 4 months of age and 24±0.3 kg of body weight, were used to study the anthelmintic effects of administering extracts of Salix babylonica L. (SB) and Leucaena leucocephala Lam. (LL). Lambs had not been treated with anthelmintics previously and were randomly allocated into four groups of five lambs each in a completely randomized design. Treatments were as follows: control (lambs fed on total mixed ration without extracts), SB (as control plus S. babylonica L. extract at 30 ml/day), LL (as control plus L. leucocephala Lam. extract at 30 ml/day), and SBLL (as control plus 30 ml/day of S. babylonica L. and L. leucocephala Lam. extracts in a 1:1 (v/v) mixture) for 63 days. Extracts were orally administered before the 8:00 a.m. feeding to each lamb. Rectal fecal samples were collected from each lamb at day 22 (P1), day 43 (P2), and day 63 (P3) of the experiment. Adult worm and egg counts were determined in each fecal sample immediately after collection. Plant secondary metabolites of total phenolics, saponins, and the aqueous fraction were 50 % lower in the SB versus LL extracts. Overall, the oral administration of extracts has improved the egg and worm count reductions in lamb feces by 54, 47, and 40 % for LL, SB, and SBLL, respectively, versus the control lambs. Reductions of worm egg counts in lamb feces were higher (P <0.05) in P2 and P3 versus P1. Extracts of SB and LL or possibly isolated bioactive compounds could be a promising alternative to conventional anthelmintics to treat gastrointestinal parasites of small ruminants. Such treatments could be used in control strategies against gastrointestinal nematodes in organic and conventional production systems
Influence of Salix babylonica and Leucaena leucocephala leaf extracts on ruminal fermentation characteristics, urinary purine derivative excretion and microbial protein synthesis of lambs
Extract of L. leucocephala or S. babylonica leaves was prepared as described before in Salem et al. (2011a). Briefly, leaves of each tree species were collected randomly from several young and mature trees during summer. Leaves (1.25 kg) were fresh chopped into 1 to 2 cm lengths and immediately extracted in 10 l of a solvent mixture containing 1 l of methanol, 1 l of ethanol and 8 l of distilled water. Extraction was at 25–301 C for 48–72 h in 20 l closed jars, followed by incubation at 391 C for 1 h, and then filtered. Filtrates were collected and stored at 41 C for further use. Plant extracts were weekly prepared. The 1:1 mixture extract was also prepared weekly by mixing the SB and LL extracts (0.5:0.5, vol:vol).Sixteen growing Katahdin Pelibuey lambs (2470.3 kg body weight) were used to study the effects of oral administration of extracts of Salix babylonica (SB) and Leucaena leucocephala (LL) leaves on ruminal pH, total and individual volatile fatty acids (VFA) and NH3-N concentrations, as well as ruminal protozoal counts, urinary purine derivatives (PD) excretion and estimated microbial protein synthesis. Lambs were fed a total mixed ration (TMR) containing 219 and 141 g kg 1 of CP and NDF, respectively. Four treatments (4 lambs/treatment) were Control (no extract added), SB (SB extract at 30 ml d 1), LL (LL extract at 30 ml d 1) and SBLL (mixture of SB at 15 ml d 1þLL at 15 ml d 1). Extracts were administered orally to each lamb before the morning meal daily. Measurements were on days 22 (P1), 43 (P2) and 63 (P3) of the experiment. Ruminal pH increased (P¼0.014) with SBLL extract and decreased with SB. The ratio of acetate to propionate was higher (P¼0.042) with SBLL compared to the control. Ruminal NH3-N concentration was not affected by extract administration (P¼0.309) or experimental period (P¼0.087). Protozoal counts were not affected (P¼0.489) by extract addition but decreased (Po0.001) in P3 compared with P1 and P2. Uric acid concentration increased (Po0.001) with individual extracts of SB and LL compared with the control or SBLL. Excretion of other purine derivatives (allantoin, xanthine, and hypoxanthine), creatinine and microbial protein synthesis were not changed (P40.05) by extracts administration. Overall, oral administration of S. babylonica and L. leucocephala extracts, or their 1:1 mixture, to lambs for 63 d had only minor effects on ruminal fermentation, urinary purine derivative excretion and microbial protein synthesis
PLANEACIÓN DIDÁCTICA GENERAL DE LA ASIGNATURA: FILOSOFÍA
GUÍA DIDÁCTICA / PLANEACIÓN DIDÁCTICA (NMS
SARS-CoV-2 en pediatría. Historia de una pandemia desde China hasta Colombia
Introduction: Coronavirus until 1930 were part of the viruses that only disturbed the animal niche. Severe acute respiratory syndrome due to coronavirus 2 (SARS-CoV-2) a type of coronavirus that causes coronavirus disease (COVID-19); In the last year it has become a concern for international public health due to the triggered pandemic, due to its high transmissibility and high mortality that it has caused. Objective: describe SARS-COV-2 infection in pediatrics with special emphasis on virological, epidemiological aspects, transmission mechanism, clinical manifestations, and expectations of treatment in pediatric age. Methods: A review of articles in Spanish and English was made, using valid terms, on the PubMed, ScienceDirect and Medline databases related to the disease. Articles with a publication period of no more than 5 years were considered. Results: The epidemiology, pathophysiology, clinical manifestations, complications, isolation and possibilities of treatment of SARS-CoV-2 in pediatric age are described. Conclusions: SARS-CoV-2 is highly contagious, the pediatric population has mostly mild clinical manifestations. The importance of an appropriate approach in this population is to avoid spreading to other ages of greater morbidity and mortality and possible associated complications.Introducción: Hasta 1930 los coronavirus eran parte de los virus que solo afectaban animales. El síndrome respiratorio agudo severo por Coronavirus 2 (SARS-CoV-2), es un tipo de coronavirus causante de la enfermedad por coronavirus (COVID-19), el cual se ha convertido en un importante problema para la salud pública mundial por la pandemia desencadenada y su alta transmisibilidad y mortalidad. Objetivo: Describir la infección por SARS-CoV-2 en pediatría realizando especial énfasis en aspecto virológicos, epidemiológicos, mecanismo de transmisión, manifestaciones clínicas y expectativas de tratamiento en la edad pediatría. Métodos: Se hizo una revisión de artículos en español e inglés, usando términos estandarizados, sobre las bases de datos PubMed, ScienceDirect y Medline relacionados con la enfermedad. Se tuvieron en cuenta artículos con periodo de publicación no mayor a 5 años. Resultados: Se describe la epidemiologia, fisiopatología, manifestaciones clínicas, complicaciones, aislamiento y posibilidades de tratamiento de SARS-CoV-2 en edad pediátrica Conclusiones: SARS-CoV-2 es altamente contagioso, la población pediátrica tiene en su mayoría manifestaciones clínicas moderadas y leves. La importancia del abordaje adecuado en esta población es evitar la propagación a personas con edades de mayor morbimortalidad y posibles complicaciones asociadas
Propuesta de Supply Chain Management y Logística para la empresa Biocombustibles sostenibles del Caribe S.A
Este documento está generalizado sobre Propuesta de supply chain management y logística para la empresa Biocombustibles Sostenibles del Caribe S.A.
donde podemos entender como se manejan todos sus procesos de distribución basado en herramientas logística para su mejor desempeño, realizando investigaciones sobre sus procesos, producto y sus múltiples facetas en su buen servicio o cuales son sus metas y objetivos.This document is generalized about Supply chain management and logistics proposal for the company Biocombustibles Sostenibles del Caribe S.A.
where we can understand how all their distribution processes are managed based on logistics tools for their best performance, conducting research on their processes, product and their multiple facets in their good service or what their goals and objectives are
Hemodynamic-based Assessment and Management of Cardiogenic Shock
Cardiogenic shock (CS) remains a deadly disease entity challenging patients, caregivers, and communities across the globe. CS can rapidly lead to the development of hypoperfusion and end-organ dysfunction, transforming a predictable hemodynamic event into a potential high-resource, intense, hemometabolic clinical catastrophe. Based on the scalable heterogeneity from a cellular level to healthcare systems in the hemodynamic-based management of patients experiencing CS, we present considerations towards systematic hemodynamic-based transitions in which distinct clinical entities share the common path of early identification and rapid transitions through an adaptive longitudinal situational awareness model of care that influences specific management considerations. Future studies are needed to best understand optimal management of drugs and devices along with engagement of health systems of care for patients with CS
Repensando el turismo sustentable
El libro aborda la problemática del turismo sustentable que, por un lado, al compartir contornos nebulosos con la sustentabilidad, funciona como un nuevo circuito de acumulación fundamentado en un discurso retórico de desarrollo local; por el otro, se nos presenta como una alternativa potencial para la formulación de vías comunitarias de desarrollo local, que permitirían la prosperidad o al menos la sobrevivencia de culturas y territorios partucularizados.Universidad Autónoma del Estado de Méxic
Ciencias de la Biología y Agronomía
Este volumen I contiene 17 capítulos arbitrados que se ocupan de estos asuntos en Tópicos Selectos de Ciencias de la Biología y Agronomía, elegidos de entre las contribuciones, reunimos algunos investigadores y estudiantes. Se presenta un Estudio Comparativo de los Recursos Hidrológico-Forestales de la Microcuenca de la Laguna de Epatlan, Pue. (1993 a 2014); la Situación Actual de la Mancha de Asfalto en Maíz (Zea mays L.) en los Municipios de Jiquipilas y Ocozocoautla, Chiapas, México; las poblaciones sobresalientes de maíz de la raza Zapalote Chico, en la Región Istmeña de Oaxaca; Se indica el índice de área foliar de cultivo de Chile Poblano mediante dos métodos en condiciones protegidas; Esquivel, Urzúa y Ramírez exploran el efecto de la biofertilización con Azospirillum en el crecimiento y producción de Jitomate; esbozan su artículo sobre la determinación del nivel de Heterosis en híbridos de Maíz para la Comarca Lagunera; una investigación sobre la estabilización de semilla de Solanum lycopersicum durante el almacenamiento y estimulación de la germinación; acotan sobre el CTAB como una nueva opción para la detección de Huanglongbing en cítricos, plantean su evaluación sobre el aluminio y cómo afecta la vida de florero de Heliconia psittacorum; indican sobre el impacto del H-564C, como un híbrido de maíz con alta calidad de proteina para el trópico húmedo de México; presetan su investigación sobre la producción de Piña Cayena Lisa y MD2 (Ananas comosus L.) en condiciones de Loma Bonita, en Oaxaca; acotan sobre el efecto de coberteras como control biológico por conservación contra áfidos en Nogal Pecanero; esbozan sobre la caracterización de cuatro genotipos de Frijol Negro en Martínez de la Torre, Veracruz, México; presentan una caracterización hidroecológica de la microcuenca de Arroyo Prieto, Yuriría, Gto., y alternativas para su restauración ambiental; presentan su investigación sobre el efecto del hongo Beauveria bassiana sobre solubilización de fosfatos y la disponibilidad de fósforo en el suelo; plantean su investigación sobre la Germinación y regeneración in vitro de Epidendrum falcatum LINDL; esbozan su artículo sobre genotipos de frijol negro y su tolerancia a sequía terminal en Veracruz, México
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