Comparative Exergy and Environmental Assessment of the Residual Biomass Gasification Routes for Hydrogen and Ammonia Production.

The need to reduce the dependency of chemicals on fossil fuels has recently motivated the adoption of renewable energies in those sectors. In addition, due to a growing population, the treatment and disposition of residual biomass from agricultural processes, such as sugar cane and orange bagasse, or even from human waste, such as sewage sludge, will be a challenge for the next generation. These residual biomasses can be an attractive alternative for the production of environmentally friendly fuels and make the economy more circular and efficient. However, these raw materials have been hitherto widely used as fuel for boilers or disposed of in sanitary landfills, losing their capacity to generate other by-products in addition to contributing to the emissions of gases that promote global warming. For this reason, this work analyzes and optimizes the biomass-based routes of biochemical production (namely, hydrogen and ammonia) using the gasification of residual biomasses. Moreover, the capture of biogenic CO2 aims to reduce the environmental burden, leading to negative emissions in the overall energy system. In this context, the chemical plants were designed, modeled, and simulated using Aspen plus™ software. The energy integration and optimization were performed using the OSMOSE Lua Platform. The exergy destruction, exergy efficiency, and general balance of the CO2 emissions were evaluated. As a result, the irreversibility generated by the gasification unit has a relevant influence on the exergy efficiency of the entire plant. On the other hand, an overall negative emission balance of -5.95 kgCO2/kgH2 in the hydrogen production route and -1.615 kgCO2/kgNH3 in the ammonia production route can be achieved, thus removing from the atmosphere 0.901 tCO2/tbiomass and 1.096 tCO2/tbiomass, respectively.

Improved Waste Heat Management and Energy Integration in an Aluminum Annealing Continuous Furnace Using a Machine Learning Approach.

Annealing furnaces are critical for achieving the desired material properties in the production of high-quality aluminum products. In addition, energy efficiency has become more and more important in industrial processes due to increasing decarbonization regulations and the price of natural gas. Thus, the current study aims to determine the opportunities to reduce energy consumption in an annealing continuous furnace and the associated emissions. To this end, the heat transfer phenomenon is modeled and solutions for the decreasing fuel consumption are evaluated so that the overall performance of the process is enhanced. A heat transfer model is developed using the finite difference method, and the heat transfer coefficient is calculated using machine learning regression models. The heat transfer model is able to predict the heat transfer coefficient and calculate the aluminum temperature profile along the furnace and the fuel consumption for any given operating condition. Two solutions for boosting the furnace exergy efficiency are evaluated, including the modulation of the furnace temperature profiles and the energy integration by the recycling of exhaust flue gases. The results show that the advanced energy integration approach significantly reduces fuel consumption by up to 20.7%. Sensitivity analysis demonstrates that the proposed strategy can effectively reduce fuel consumption compared with the business-as-usual scenario for a range of sheet thicknesses and sheet velocities.

Use of computed tomography and radiation therapy planning software to develop a novel formula for body surface area calculation in dogs.

BACKGROUND: Body surface area (BSA) can reflect metabolic rate that might normalize dosing of chemotherapeutics across widely variable weights within a species. The current BSA formula for dogs lacks height, length, and body condition. HYPOTHESIS: Computed tomography (CT) imaging will allow inclusion of morphometric variables in allometric modeling of BSA in dogs resulting in an improved formula for BSA estimation. ANIMALS: Forty-eight dogs from 4 institutions with whole-body CT images. METHODS: Retrospective and prospective case series. Body surface area was contoured using whole-body CT scans and radiation therapy planning software. Body length and height were determined from CT images and also in 9 dogs by physical measurement. Nonlinear regression was used to model the BSA data sets using allometric equations. Goodness-of-fit criteria included average relative deviation, mean standard error, Akaike information criterion, and r2 (derived from the r-value generated by regression models). RESULTS: Contoured BSA differed from the current formula by -9% to +19%. Nonlinear regression on untransformed data yielded BSA = 0.0134 × body weight [kg]∧ 0.4746 × length (cm)∧ 0.6393 as the best-fit model. Heteroscedasticity (increasing morphometric variability with increasing BSA) was an important finding. CONCLUSIONS AND CLINICAL IMPORTANCE: Computed tomography-derived BSA was used to incorporate body length into a novel BSA formula. This formula can be applied prospectively to determine whether it correlates with adverse events attributed to chemotherapy.

Hidatidosis quística simulando una neoplasia hepática invasiva / Cystic hydatidosis simulating an invasive hepatic neoplasia

La hidatidosis/equinococosis quística es una infección zoonótica, endémica en muchos países de América del Sur, caracterizada por lesiones hepáticas que radiológicamente pueden simular neo-plasias malignas de aspecto quístico y que, dependiendo del tiempo de evolución y del grado de obstrucción de la vía biliar, pueden cursar con insuficiencia hepática, por lo cual es importante un diagnóstico oportuno. Presentamos el caso de un paciente masculino de 35 años, sin antecedentes patológicos de importancia, perteneciente a una comunidad indígena y residente de una zona rural de Colombia, quien presentó un cuadro clínico y pruebas de laboratorio sugestivos de obstrucción de la vía biliar, la cual fue confirmada con el hallazgo de una masa hepática quística infiltrante en los estudios imagenológicos, sospechándose inicialmente una etiología neoplásica maligna. El paciente finalmente falleció tras procedimiento quirúrgico, y su estudio histopatológico reveló una hidatidosis quística como diagnóstico definitivo.

Cystic echinococcosis/hydatidosis is a zoonotic infection, endemic in many South American coun-tries, characterized by liver lesions that radiologically can simulate malignant neoplasms with a cystic appearance, and depending on the time of progression and degree of obstruction of the bile duct, can present with liver failure, so a prompt diagnosis is important. We present the case of a 35-year-old male patient, with no significant pathological history, from an indigenous community and resident of a rural area in Colombia, who presented clinical symptoms and laboratory tests suggestive of bile duct obstruction, which was confirmed with the finding of an infiltrating cystic liver mass in imaging studies, initially suspecting a malignant neoplastic etiology. The patient developed a fulminant course after surgery, and the histopathological study revealed cystic hydatidosis as the definitive diagnosis.

Nivel de actividad física y estado de ánimo en universitarios durante el confinamiento por la COVID-19

Introducción: La pandemia de la COVID-19 ha generado problemas de salud física y mental en los universitarios. Objetivos: Determinar la relación entre nivel de actividad física y estado de ánimo en estudiantes universitarios durante el confinamiento por la COVID-19. Métodos: Participaron 215 estudiantes universitarios, edad 22,09 ± 2,61 (108 mujeres y 107 hombres) durante el confinamiento por la COVID-19. Fueron aplicados instrumentos en formato digital durante el mes de junio del año 2020. El nivel de actividad física se evaluó utilizando el Cuestionario Internacional de Actividad Física (IPAQ), forma corta, y el estado de ánimo se evaluó con la Escala de Valoración del Estado de Ánimo (EVEA). Resultados: Estado de ánimo alegría presentó una correlación positiva significativa con todas las variables de actividad física, excepto con tiempo sentado. Estado de ánimo tristeza-depresión presentó una correlación negativa con equivalente metabólico de actividad física vigorosa (r -0,201; p= 0,003) y equivalente metabólico total (r -0,172; p= 0,011). Estado de ánimo ansiedad se correlacionó negativamente con equivalente metabólico de actividad física vigorosa (r -0,163; p= 0,017) y equivalente metabólico total (r -0,162; p= 0,018). Conclusiones: El nivel de actividad física se relaciona positivamente con el estado de ánimo, principalmente con el nivel de alegría, sin embargo, estas correlaciones presentan un tamaño del efecto pequeño.

Introduction: The COVID-19 pandemic has generated physical and mental health problems in university students. Objectives: To determine the relationship between physical activity level and mood in university students during COVID-19 confinement. Methods: 215 university students aged 22.09 ± 2.61 (108 women and 107 men) participated during the confinement due to the COVID-19 pandemic. Instruments in digital format were applied during the month of June 2020. Physical activity level was assessed using the International Physical Activity Questionnaire (IPAQ) short form and mood was assessed using the Mood Rating Scale (EVEA). Results: Mood joy presents a significant positive correlation with all variables of physical activity, except with sitting time. Sadness-depression mood showed a negative correlation with metabolic equivalent of vigorous physical activity (r -0.201; p= 0.003) and total metabolic equivalent (r -0.172; p= 0.011). Mood anxiety was negatively correlated with metabolic equivalent of vigorous physical activity (r -0.163; p= 0.017) and total metabolic equivalent (r -0.162; p= 0.018). Conclusions: The level of physical activity is positively related to mood, mainly with the level of joy, however, these correlations have a small effect size.