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An integrated membrane process for treatment of effluents from food additive manufacturing was designed and evaluated on a laboratory scale. The principal focus was water recovery with the possibility of its reuse as potable water. The industrial effluent presented high content of dyes and salts. It was red in color and presented brine characteristics. The whole effluent was fed into the integrated process in continuous flow. The steps of the process are as follows: sedimentation (S), adsorption by activated carbon (AC), ion exchange using resins (IEXR), and reverse osmosis (RO) (S-AC-IEXR-RO). The effect of previous operations was evaluated by stress-rupture curves in packaged columns of AC and IEXR, membrane flux, and fouling dominance in RO. Fouling was evaluated by way of the Silt Density Index and membrane resistance examination during effluent treatment. The integrated membrane process provided reclaimed water with sufficiently high standards of quality for reuse as potable water. AC showed a high efficiency for color elimination, reaching its rupture point at 20 h and after 5L of effluent treatment. IEXR showed capacity for salt removal, providing 2.2-2.5 L of effluent treatment, reaching its rupture point at 11-15 h. As a result of these previous operations and operating conditions, the fouling of the RO membrane was alleviated, displaying high flux of water: 20-18 L/h/m2 and maintaining reversible fouling dominance at a feed flow rate of 0.5-0.7 L/h. The characteristics of the reclaimed water showed drinking water standards.

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Deep eutectic solvents (DES) using magnesium chloride hexahydrate [MgCl2·6H2O] and urea [U] proportions (1:1) and (2:1), were prepared for their use as extracting and stabilizer agents for red and violet betalains from beetroot (Beta vulgaris) waste. The synthetized DES [MgCl2·6H2O] [U] showed similar properties to eutectic mixtures, such as, liquid phase, low melting points and conductivity, thermal stability, and variable viscosity. In turn, betalain DES extracts (2:1) exhibited compatibility in the extraction and recovery of betalains from beetroot wastes, showing a betalain content comparable to that of betalain extracts. Betalain stability was determined by degradation tests; the exposure conditions were visible light (12 h), molecular oxygen from atmospheric air and environmental temperature (20-27 °C) for 40 days. The kinetic curves of the betalain degradation of water samples depicted a first-order model, indicating the alteration of a violet colouration of betalains from beetroot waste for 5-7 days. However, betalains from DES extracts were kept under visible light for 150 days, and for 340 days in storage (amber vessels), achieving a stability of 75% in comparison with initial beet extracts.

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Antihypertensive peptide fraction from whey protein hydrolysate <3 kDa (measured as angiotensin-converting enzyme (ACE) activity %) was isolated and encapsulated into three composite materials: alginate-collagen, alginate Arabic gum, and alginate-gelatin. The release behavior of peptide fraction from capsules was analyzed according to the encapsulation material efficiency, the characteristics of the capsules, and the released antihypertensive peptides during gastrointestinal digestion. The highest encapsulation efficiency was found in capsules of alginate Arabic gum (95%). In this case, the released peptides incremented their ACE activity (85%) after the digestion process, with respect to the initial ACE activity (74%). Whey antihypertensive fraction revealed five peptide sequences; however, other amino acid sequences were released from digested capsules. Protein databases confirmed some antihypertensive sequences indicating the peptides content from ß-Lg and α-La. Consequently, new peptides could be revealed from whey antihypertensive fraction.

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La motivación es parte de la conducta humana que determina que una persona inicie una acción, se desplace hacia un objetivo y persista en sus metas para alcanzarlo, aunque no es una variable observable, si un constructor hipotético, que fue estudiado como un predictor de la permanencia de los estudiantes en la carrera de enfermería. Por lo que el objetivo de este estudio fue de describir y comparar los factores motivacionlaes que generan satisfacción escolar y que influyen para permanencia en los estudios de los alumnos de licenciatura en enfermería. Para lograr el objetivo se realizó un estudio cuantitativo, correlacional, transversal, con 200 alumnos de 2° y 4° semestre de la licenciatura en enfermería de una escuela pública del D.F. Las variables que se incluyeron fueron: factores motivacionales, intriscecos, extrínsecos y de satisfacción. Para capturar la información se aplicó un cuestionario que tiene una confiabilidad de 8787 con la prueba de alpha de Cronbach. Y para análisis de los datos se aplicó la prueba t de Student y ANOVA. Dentro de los resultados más importantes se tiene que a maoyr nivel de satisfacción en motivadores estrínsecos e intrinsecos los allumnos de 2° semestre esto explica que 6 de cada 10 tiene alta motivación mientras que sólo 4 de cada 10 de alta motivación se ubican en 4°. El nivel de motivacilón intrínseca es mayor que la extrínseca y existe una relación moderada entre estas dos con nivel de satisfacción general. Se concluye que la hipótesis de estudio donde se plantea que a mayor motivación intrinseca y extrinseca mayor satisfacción en el estudio, así como la permanencia del alumno en la carrera es aceptada.

Motivation is part of human behavior that determines that a person initiates an action, moves towards a goal and persists in its goals to achieve it, although it is not an observable variable, if a hypothetical construct, which was studied as a predictor of Permanence of the students in the nursing career. Therefore, the objective of this study was to describe and compare the motivational factors that generate school satisfaction and that influence for permanence in the studies of undergraduate students in nursing. To achieve the objective, a quantitative, correlational, cross-sectional study was carried out with 200 students from the 2nd and 4th semester of the undergraduate nursing degree from a D.F. public school. The variables that were included were: motivational, intrinsic, extrinsic and satisfaction factors. To capture the information a questionnaire was applied that has a reliability of 8787 with the Cronbach alpha test. Data were analyzed using Student's t-test and ANOVA. Among the most important results is that at the same level of satisfaction in intrinsic and intrinsic motivators the students of 2nd semester this explains that 6 out of 10 have high motivation but only 4 out of 10 of high motivation are located in 4 ° . The level of intrinsic motivaci6n is greater than the extrinsic motivaci6n and there is a moderate relationship between these two with a level of general satisfaction. It is concluded that the hypothesis of study where it is proposed that the greater intrinsic and extrinsic motivation greater satisfaction in the study, as well as the student's permanence in the career is accepted.

A motivação é parte do comportamento humano que determina que uma pessoa inicia uma ação, se move em direção a um objetivo e persiste em seus objetivos para alcançá-lo, embora não seja uma variável observável, se uma construção hipotética, que foi estudada como preditor de Permanência dos alunos na carreira de enfermagem. Portanto, o objetivo deste estudo foi descrever e comparar os fatores motivacionais que geram satisfação escolar e essa influência para a permanência nos estudos de estudantes de graduação em enfermagem. Para atingir o objetivo, realizou-se um estudo quantitativo, correlacional e transversal, com 200 alunos do 2º e 4º semestre do curso de graduação de enfermagem de uma escola pública de D.F. As variáveis ​​incluídas foram: fatores motivacionais, intrínsecos, extrínsecos e de satisfação. Para capturar a informação, foi aplicado um questionário com uma confiabilidade de 8787 com o teste alfa de Cronbach. Os dados foram analisados ​​utilizando o teste t de Student e ANOVA. Entre os resultados mais importantes, é que, no mesmo nível de satisfação em motivadores intrínsecos e intrínsecos, os alunos do 2º semestre, isso explica que 6 de cada 10 têm alta motivação, mas apenas 4 em cada 10 de alta motivação estão localizados em 4 °. . O nível de motivação intrínseca é maior do que a motivação extrínseca e existe uma relação moderada entre estes dois com um nível de satisfação geral. Conclui-se que a hipótese de estudo, onde se propõe que seja aceita a maior motivação intrínseca e extrínseca maior satisfação no estudo, bem como a permanência do aluno na carreira.

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Shade-grown coffee is an agricultural system that contains some forest-like characteristics. However, structure and diversity are poorly known in shade coffee systems. In 61 coffee-growers' plots of Chiapas, Mexico, structural variables of shade vegetation and coffee yields were measured, recording species and their use. Coffee stands had five vegetation strata. Seventy seven woody species mostly used as wood were found (mean density 371.4 trees per hectare). Ninety percent were native species (40 of the local flora), the remaining were introduced species, mainly fruit trees/shrubs. Diametric distribution resembles that of a secondary forest. Principal Coordinates Analysis grouped plots in four classes by the presence of Inga, however the majority of plots are diverse. There was no difference in equitability among groups or coffee yields. Coffee yield was 835 g clean coffee per shrub, or ca. 1,668 kg ha-1. There is a significant role of shade-grown coffee as diversity refuge for woody plants and presumably associated fauna as well as an opportunity for shade-coffee growers to participate in the new biodiversity-friendly-coffee market.

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