Polymeric gels have been an important category for material scientists due its versatile structural features. Hence, hydrogels are being used to reduce excess production water in oil reservoirs. In this work, cross-linked partially hydrolyzed polyacrylamide (HPAM) composite hydrogels impregnated with bentonite clay (Bent) and bentonite clay modified (Orgbentent) with the surfactant hexadecyltrimethylammonium bromide were synthesized and characterized as a sealing agent in high water producing permeable zones in the petroleum industry. The concept of utilizing hydrophobically modified clay as an inorganic additive in the hydrogel matrix emanates from the fact that this additive exhibit greater interaction with the polymer chains. These interactions can promote the inherent properties of the hydrogel. Polyethyleneimine (PEI) was chosen as the cross-linking agent. HPAM/PEI conventional hydrogels and HPAM/PEI/Bent and HPAM/PEI/Orgbent at 100 mg•L −1 clay were synthesized. The developed hydrogels were characterized by a hybrid rheometer and Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and thermogravimetric analysis (TGA) instruments. Rheological results reveal that the (HPAM/PEI/Bent-3 and HPAM/PEI/Orgbent-3) composite hydrogels showed higher elastic modulus (G′) and durability in the studied conditions (stable at 30 days) than conventional ones (HPAM/PEI), indicating the dispersion and reinforcing effect of clay. The functional groups of these hydrogels were confirmed by FTIR, and TGA demonstrated the structural reinforcement due to the presence of the clays, which had lower weight loss than the conventional hydrogel. The hydrogel morphologies were analyzed by SEM, and the results corroborated with those obtained by TGA, indicating better structural reinforcement when using organophilic clay.

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BACKGROUND: Poor appetite is common through the aging process and increases the risk of weight loss, protein-energy malnutrition, immunossupression, sarcopenia and frailty. The Simplified Nutritional Appetite Questionnaire (SNAQ) has the aim to monitor appetite and identify older adults at risk of weight loss. OBJECTIVE: To describe the process of translation and cultural adaptation to Brazilian Portuguese of the SNAQ. METHODS: The translation and cultural adaptation was developed in five steps: translation (by three of the authors of the manuscript and assembled by consensus), backtranslation (by an English native speaker), semantic evaluation (by one verontologist and one nutritionist), comprehension of content (by nutrition specialists and by a group of older persons), pre-test and the SNAQ final version development. RESULTS: The SNAQ Portuguese version maintained the original version meaning and referral. To achieve this feature, the process required some modifications to improve the understanding of older persons, such as inclusion of other options to the answers of some questions, rewritten of one question and inclusion of a meal definition. CONCLUSION: SNAQ questionnaire has been successfully translated and adapted to Portuguese. As our next step, we are validating this tool in different clinical settings in Brazil.

We investigated changes in lifestyle, depressive symptoms, self-perception of health, and body weight changes of persons living with HIV (PLWH) during the COVID-19 social distancing (SD). In a Web-based cross-sectional survey, participants (n = 406) were questioned about lifestyle and health status before and during SD. Most responders were men, 50 + years old, high education level; 49.8% had their income reduced during SD. About 9% were diagnosed with COVID-19, of whom 13.5% required hospitalization. During SD: -most participants did not change their food intake, although 25% replaced healthy foods with unhealthy ones; -more than half mentioned poor sleep quality; -about 50% increased their sedentary behavior. Depressive symptoms (reported by 70.9%) were associated with sedentary behavior, poor sleep quality, and reduced income. About one-third had a negative perception of their health status, which was inversely associated with practicing physical exercises and positively associated with sedentarism and poor sleep quality. More than half increased their body weight, which was associated with a lower intake of vegetables. The older age reduced the odds of the three outcomes. Carefully monitoring PLWH regarding SD will enable early interventions toward health. Keywords COVID-19 • HIV • Lifestyle • Depressive symptoms • Body weight • Health ResumenEn este trabajo investigamos los cambios en el estilo de vida, síntomas depresivos, autopercepción de salud y cambios en el peso corporal de las personas que viven con el VIH (PVCV) durante el distanciamiento social (DS) de COVID-19. En una encuesta transversal en línea, se preguntó a los participantes (n = 406) sobre el estilo de vida y el estado de salud antes y durante el DS. La mayoría de los encuestados eran hombres, mayores de 50 años, con alto nivel educativo. El 49,8% tuvo una disminución en sus ingresos durante el DS. El 9,1% fue diagnosticados con COVID-19, de los cuales 13,5% requirió hospitalización. Durante el DS: -la mayoría de los participantes no cambió su ingesta de alimentos, aunque el 25% reemplazó los alimentos saludables por los no saludables; más de la mitad mencionó mala calidad del sueño; cerca del 50% aumentó su comportamiento sedentario. Los síntomas depresivos (referidos por el 70,9%), fueron incrementados por el sedentarismo, la mala calidad del sueño y reducción de la renta. Cerca de un tercio tenía una percepción negativa de su estado de salud, que se redujo con la práctica de ejercicio físico y aumentó con el sedentarismo y la mala calidad del sueño. Más de la mitad aumentó su peso corporal, lo que se asoció con una menor ingesta de vegetales. Una edad más avanzada redujo las probabilidades de los tres desenlaces. El monitoreo cuidadoso de las PVCV con respecto al DS permitirá intervenciones tempranas para la salud. Palabras clave: COVID-19 • VIH • estilo de vida • síntomas depresivos • peso corporal • salud

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