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Dairy operations generate large volumes of polluted wastewater that require treatment prior to discharge. Chemically enhanced primary treatment (CEPT) is a widely utilized wastewater treatment strategy; but it requires the use of non-biodegradable coagulants that can lead to toxic-byproducts. In this study, chitin from shrimp shell waste is extracted and converted into chitosan. Chitosan was demonstrated to be a natural, low-cost alternative coagulant compatible with the CEPT. Following treatment, dissolved air flotation allowed for the removal of turbidity, COD, and UV254 from the synthetic dairy effluent (SDE). Doehlert matrix was used to optimize the chitosan dosage and pH of the CEPT; as well as to model the process. The mechanisms behind the coagulation-flocculation were revealed using zeta potential analysis. FTIR spectroscopy was utilized to confirm the functional groups present on the chitosan. Chitosan with a degree of deacetylation equal to 81% was obtained. A chitosan dose of 73.34 mg/L at pH 5.00 was found to be optimal for the removal of pollutants. Removals of COD, turbidity and UV254 were 77.5%, 97.6%, and 88.8%, respectively. The amount of dry sludge generated to treat 1 m³ of SDE was 0.041 kg. Coagulation-flocculation mechanisms involved in chitosan-mediated treatment of SDE involve the neutralization of electrostatic charges carried on the amine groups present in cationic chitosan at pH 5.00. Doehlert matrix proved to be a useful tool in optimizing parameters throughout the coagulation-flocculation process. Chitosan from shrimp waste is a low-cost, eco-friendly coagulant alternative for the removal pollutants from dairy effluent using the CEPT.

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INTRODUÇÃO: O aumento de publicações sobre a vida do estudante do Ensino Superior demonstra o interesse crescente da comunidade científica sobre o tema. Tais estudos apontam para alterações na saúde dessa população após ingresso nesse nível de ensino. OBJETIVO: Investigar mudanças nos hábitos de vida dos estudantes que ingressam na universidade e o impacto em sua saúde física e mental. MÉTODOS: Foi adotada uma pesquisa qualitativa, com o uso de entrevista semiestruturada, aplicada em oito estudantes. Os dados foram analisados mediante análise de conteúdo, o que resultou em três categorias temáticas: Mudanças nos hábitos (alimentação, sono, atividades físicas, lazer e descanso); Impactos (físicos e mentais); Determinantes envolvidos na formação de novos hábitos (socioeconômicos, acadêmicos, familiares e afetivos e outros). RESULTADOS: A alimentação foi uma das dimensões que mais apresentou alterações, assim como o sono. Quanto aos impactos físicos, foram apontadas dores musculares, cefaleias tensionais, enxaquecas e agravamento de distúrbios, como gastrite. Nos impactos mentais, registrou-se os sintomas de estresse, cansaço, desmotivação e sentimentos de solidão, impotência, isolamento, desejo de desistir e agravamento de sofrimentos psíquicos já existentes, como depressão e ansiedade. Os determinantes mais frequentes foram os sociais, que abrangem as condições socioeconômicas dos estudantes, seguido dos educacionais, que abrangem o ambiente acadêmico. CONCLUSÃO: A experiência no Ensino Superior, neste caso, na universidade, provoca mudanças nos hábitos dos estudantes após ingresso, o que resulta em impactos em sua saúde e sugere a necessidade de se repensar as formas de seu funcionamento.

INTRODUCTION: The increasing number of publications about university students' lives reveals the growing interest that the scientific community holds in this theme. Such studies point to changes in the health of this population after entering this level of education. OBJECTIVE: The present study investigates changes in these students' daily habits after they start college and their impact on their physical and mental health. METHODS: A qualitative research was adopted, and semistructured interviews were applied to eight students. Data was verified using a content analysis technique, which resulted in three thematic categories: Habits variations (feeding, sleeping, physical activities practice, resting and leisure); life impacts (physical and mental); Determinants involved in these new habits acquisition (socioeconomic, academic, family and affective and others). RESULTS: Feeding and sleeping were dimensions that presented most transitions. The most common physical impacts were headache, migraine, muscle ache, and worsening of previous conditions such as gastritis. Regarding mental impacts, the following symptoms were registered: tiredness, stress, demotivation, loneliness, helplessness feelings, isolation, thoughts about giving up, and aggravation in previous psyche suffering as depression and anxiety. The noun determinants related to these changes were the social, which include the students' socioeconomic conditions, followed by the educational elements that comprehend the academic environment. CONCLUSION: A university's academic daily life generates multiple routine changes in their students, compromising their health. Therefore, restructuring universities organizations is needed.

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A feasible, novel, and natural coagulant extracted from G. ulmifolia stem bark was characterized and used in experiments of coagulation/dissolved air flotation (C/DAF) to treat synthetic dairy wastewater (SDW). The performance of G. ulmifolia to remove turbidity, chemical oxygen demand (COD), and UV254 was evaluated by using response surface methodology (Doehlert matrix). G. ulmifolia dosage and pH were evaluated and optimized in the C/DAF process and its characterization was performed by Fourier Transform Infrared (FTIR) spectroscopy, Scanning Electron Microscopy (SEM), and also zeta potential. Results showed that G. ulmifolia stem bark is composed of large quantities of condensed tannins represented by the groups C=C-C and CO of pyran (flavonoid C-rings), which serve as bridges during coagulation. Moreover, the presence of porous cavities in surface of G. ulmifolia, shown by SEM, indicated capacity for adsorption. G. ulmifolia dosage and pH were significant (p ≤ 0.05) for pollutant removal from the SDW. Jar test results revealed that 95.8% of turbidity, 76.0% of COD, 81.2% of BOD, and 85.6% of UV254 were removed from SDW by using G. ulmifolia stem bark at a dose of 775.8 mg L-1 and pH 5.00. Finally, our results showed promising use of G. ulmifolia as a coagulating agent due to its novelty, efficiency, low-cost, and eco-friendly properties as an alternative for the treatment of dairy wastewaters.

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The objective of this study was to predict chloroform formation resulting from the process of disinfecting water, particularly trihalomethane which is most frequently produced. A statistical model was used which included repeated measurements of water parameters used for monitoring water quality at 51 sites covering the municipal water system of Montevideo. Samples were taken considering different seasons from June 2009 to July 2011 in Montevideo. Total samples (n = 330) were analytically studied using the headspace-gas chromatography method coupled with mass spectrometry. Chloroform was the dependent variable and the covariables were pH, temperature, free chlorine, and total chlorine. A Tobit analysis with an unstructured correlation matrix was performed, and a significant interaction was found between pH and free chlorine for the prediction of chloroform formation. We concluded that parameters for the continuous control of water quality for consumption can be used to predict the levels of chloroform that may be present. Given the large measurement to variability found in the repeated measurements, the use of averages that include more than one season is not recommended to determine the degree of compliance with acceptable levels established by norms.

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Se disecaron 86 arterias hepáticas de cadáveres adultos valorando aquellos aspectos de su anatomía de interés en la cirugía del trasplante hepático. Los datos consignados fueron el número, origen, trayecto, topografía y terminación del o los pedículos arteriales del hígado, así como el calibre y la distancia al hilio hepático de cada uno de los potenciales sitios anastomóticos utilizados en el implante. Se comprobaron variaciones de la disposición normal de la arteria en 37 casos (36 por ciento) dentro de las cuales se destaca la presencia de una arteria hepática derecha accesoria en 12 casos (74 por ciento), una hepática izquierda en 6 casos (7 por ciento), ausencia de hepática propia en 11 casos (13 por ciento) y topografía retroportal en 1 caso (1,2 por ciento). Promedialmente se halló un calibre de 5 mm. a nivel de la hepática común y los sitios anastomóticos se situaron en un radio de 70 mm. a partir del hilio hepático. De la discusión de estos resultados se extraen conclusiones de aplicación práctica en los tiempos de ablación e implante del órgano. (AU)

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Se disecaron 86 arterias hepáticas de cadáveres adultos valorando aquellos aspectos de su anatomía de interés en la cirugía del trasplante hepático. Los datos consignados fueron el número, origen, trayecto, topografía y terminación del o los pedículos arteriales del hígado, así como el calibre y la distancia al hilio hepático de cada uno de los potenciales sitios anastomóticos utilizados en el implante. Se comprobaron variaciones de la disposición normal de la arteria en 37 casos (36 por ciento) dentro de las cuales se destaca la presencia de una arteria hepática derecha accesoria en 12 casos (74 por ciento), una hepática izquierda en 6 casos (7 por ciento), ausencia de hepática propia en 11 casos (13 por ciento) y topografía retroportal en 1 caso (1,2 por ciento). Promedialmente se halló un calibre de 5 mm. a nivel de la hepática común y los sitios anastomóticos se situaron en un radio de 70 mm. a partir del hilio hepático. De la discusión de estos resultados se extraen conclusiones de aplicación práctica en los tiempos de ablación e implante del órgano.

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La ruptura del quiste hidático (QH) pulmonar puede provocar una hidatidosis secundaria (local, siembra bronquial, pleural secundaria). Es por ello que clásicamente se consideraba que un QH en sufrimiento era una urgencia quirúrgica. La experiencia ha demostrado que más peligroso que la ruptura, es operar un paciente con una neumonitis periquística. En el acto operatorio no se podrá realizar la broncorrafia desgarrando el parenquima pulmonar friable. Ello llevará a una aerostasis defectuosa, sangrado, reexpansión pulmonar incompleta, con el consiguiente peligro de complicaciones postoperatorias. Un enérgico tratamiento preoperatorio de la neumonitis es obligatorio no importando el estado de sufrimiento del quiste. La TAC no documentará el estado del pulmón. El objetivo de este trabajo es mostrar dos pacientes operados con una preparación correcta, donde se logró evitar complicaciones y un postoperatorio de pocos días. Por lo que concluimos que no se justifica una cirugía de urgencia, sin una preparación adecuada del parenquima pulmonar, con el fin de evitar la ruptura de un QH de pulmón

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La ruptura del quiste hidático (QH) pulmonar puede provocar una hidatidosis secundaria (local, siembra bronquial, pleural secundaria). Es por ello que clásicamente se consideraba que un QH en sufrimiento era una urgencia quirúrgica. La experiencia ha demostrado que más peligroso que la ruptura, es operar un paciente con una neumonitis periquística. En el acto operatorio no se podrá realizar la broncorrafia desgarrando el parenquima pulmonar friable. Ello llevará a una aerostasis defectuosa, sangrado, reexpansión pulmonar incompleta, con el consiguiente peligro de complicaciones postoperatorias. Un enérgico tratamiento preoperatorio de la neumonitis es obligatorio no importando el estado de sufrimiento del quiste. La TAC no documentará el estado del pulmón. El objetivo de este trabajo es mostrar dos pacientes operados con una preparación correcta, donde se logró evitar complicaciones y un postoperatorio de pocos días. Por lo que concluimos que no se justifica una cirugía de urgencia, sin una preparación adecuada del parenquima pulmonar, con el fin de evitar la ruptura de un QH de pulmón(AU)

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