2,742 research outputs found

    A New Proposal of Cellulosic Ethanol to Boost Sugarcane Biorefineries: Techno-Economic Evaluation

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    Commercial simulator Aspen Plus was used to simulate a biorefinery producing ethanol from sugarcane juice and second generation ethanol production using bagasse fine fraction composed of parenchyma cells (P-fraction). Liquid hot water and steam explosion pretreatment technologies were evaluated. The processes were thermal and water integrated and compared to a biorefinery producing ethanol from juice and sugarcane bagasse. The results indicated that after thermal and water integration, the evaluated processes were self-sufficient in energy demand, being able to sell the surplus electricity to the grid, and presented water intake inside the environmental limit for SĂŁo Paulo State, Brazil. The processes that evaluated the use of the bagasse fine fraction presented higher economic results compared with the use of the entire bagasse. Even though, due to the high enzyme costs, the payback calculated for the biorefineries were higher than 8 years for all cases that considered second generation ethanol and the net present value for the investment was negative. The reduction on the enzyme load, in a way that the conversion rates could be maintained, is the limiting factor to make second generation ethanol competitive with the most immediate uses of bagasse: fuel for the cogeneration system to surplus electricity production

    A new proposal of cellulosic ethanol to boost sugarcane biorefineries: techno-economic evaluation

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    Commercial simulator Aspen Plus was used to simulate a biorefinery producing ethanol from sugarcane juice and second generation ethanol production using bagasse fine fraction composed of parenchyma cells (P-fraction). Liquid hot water and steam explosion pretreatment technologies were evaluated. The processes were thermal and water integrated and compared to a biorefinery producing ethanol from juice and sugarcane bagasse. The results indicated that after thermal and water integration, the evaluated processes were self-sufficient in energy demand, being able to sell the surplus electricity to the grid, and presented water intake inside the environmental limit for São Paulo State, Brazil. The processes that evaluated the use of the bagasse fine fraction presented higher economic results compared with the use of the entire bagasse. Even though, due to the high enzyme costs, the payback calculated for the biorefineries were higher than 8 years for all cases that considered second generation ethanol and the net present value for the investment was negative. The reduction on the enzyme load, in a way that the conversion rates could be maintained, is the limiting factor to make second generation ethanol competitive with the most immediate uses of bagasse: fuel for the cogeneration system to surplus electricity production2014sem informaçãosem informaçãoThe authors acknowledge the financial support granted by the Agreement Unicamp-Brazil Shell Petroleum Lt

    Combination Effect of Ozone and Heat Treatment for the Color Reduction in Sugarcane Juice

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    We have been studied the mechanism of color reduction of sugarcane juice as a new innovative technology to crystal sugar production as a substitute for sulfur use, which was related to health problems. This work evaluated the effect of ozonation on sugarcane juice in two different conditions, heated and non-heated juice. The samples in both conditions were ozonized for 120 min in a stainless-steel batch reactor, connected to an ozonation system with constant flow (17.3 mg O3/min). Ozonation did not change the values ​​of reducing sugars (RS) and the apparent sucrose content (POL); however, the color rate ICUMSA showed significant decrease for the heated juice, but there was no response to ozonation in the non-heated juice. These responses represent a key point to the industry, which during the clarification process, heats the juice before the sulfitation. The settling should become more efficient after ozonation (results not shown), showing great potential to use this technology in production systems because of the optimization of reaction parameters for color reduction ICUMSA in sugarcane juice. Keywords: Ozone, Clarification, Sugarcane, ICUMSA, UFLC/ELSD

    Knowing about the Nutritional and Immunological Benefits of Breast Milk Does not Reduce Early Weaning

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    Breastfeeding brings great benefits to the child and the mother, however it is known that the practice requires encouragement and proper guidance. Even knowing the nutritional and immunological benefits of breastmilk, many mothers interrupt lactation and add artificial formulas in infant feeding, most often due to myths or difficulties in breastfeeding management. The aim of this study was to identify factors that influence early weaning in Ibiá, Minas Gerais, Brazil. It was an exploratory, transversal and quantitative research, conducted through questionnaires administered to mothers of children of 0-6 months. As for the most common problems related to breastfeeding experienced by respondents, the main reported was the presence of "milk weak "or“little milk” with 53.84%. When asked if their children were using pacifiers, 69.73% of respondents reported so. The family and professional support is of utmost importance to the practice of breastfeeding. Nursing should advise on lactation management as well as on the numerous benefits of breast feeding. The nursing team has na important role in this regard, promoting breastfeeding, with preventive actions that contribute to this important stage of the childrens life, thus, breast feeding can belived fully and satisfactorily

    Quality of infant sleep, electronic devices and bullying behaviors in schools

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    This research investigates the relationship betweenthe quality of infant sleep, the use of electronic devices and of videogames before bedtime and bullying behaviors in school context. Research Questions: Is the quality of infant sleep and the use of electronic devices at bedtime related to bullying? The use of electronic devices before bedtime affects sleep duration and latency? Purpose of the Study: To analyze the relationship between the use of electronic devices before bed and the sleep infant quality. As well as, the relation between the quality of the children sleep duration, children’ sleep latency, use of electronic devices, videogames in a daily basis, and bullying behaviors in school context. Research Methods: Participants are divided into two groups; one of these groups consists of the children who responded to the Pittsburgh Sleep Quality Index andthe Children’s Sleep Habits Questionnaire (CSHQ-PT), totalling 860. The other group had a sample of 51 children, the Sociodemographic Questionnaire and the Children’s Sleep Habits Questionnaire (CSHQ-PT) were applied. Findings: A statistically significant relationship was found between sleep quality and use of electronic devices before bed, with the exception of television. As a relationship between sleep quality and bullying behaviors, and also between using electronic gadgets before bedtime and bullying behaviors just for listening to music. Considering the sleep latency, a negative correlation was found with daily videogames use. Conclusions: There seems to be a relationship between sleep quality and bullying behaviors in school, and between the use of electronic devices and sleep quality. Also listening to music at bedtime is positively related to bullying behaviors. On the other hand, the videogames daily use before bedtime affects in a significant manner the children’ sleep latency (and the sleep REM)..info:eu-repo/semantics/publishedVersio

    Systematic review of the effects of coffee or its components on platelets and their regulators

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    Coffee includes some potentially bioactive components that can interfere with platelets, which can influence coagulation, despite generating controversy. The aim of this systematic review is to verify whether coffee or its components can influence platelet regulators and/or aggregation. Materials and Methods: The research was conducted on July 29, 2021, in PubMed, Scopus, andWeb of Science, using the followingmesh-terms: (caffeine)) OR (coffee)) AND (platelets). Eligibility criteria were: studies carried out in humans, referring to the effects of coffee consumption, or one of its components, on platelets or their regulators. We exclude in vitro or animal studies, reviews, editorials, and non-English written studies. From a total of 836 publications, 17 articles were included from which we extracted the relationship between coffee consumption and changes in blood platelets and performed a subjective assessment of bias. Results: Ten articles refer to the non-interference of coffee or its components with platelets, nine affirm results that support the increase in platelet aggregation, and eight articles observe the decrease in platelet aggregation when coffee is consumed. Some articles presented the lack of data regarding the sample collection location, age group, or classification as to the type of study, which is limiting. Conclusions: The heterogeneity of results makes it difficult to correctly interpret the possible interaction of coffee or its components with platelets or their regulators. For better interpretation, further studies on this topic should be carried out considering the individualization of coffee components, different platelet regulators, and the size of the sample used.The Centro de Investigac¸a˜o de Montanha (CIMO) received financial support from Fundac¸a˜o para Ciencia e a Tecnologia (FCT, Portugal) and from Fundo Europeu de Desenvolvimento Regional (FEDER), under PT2020 program (UIDB/00690/2020).info:eu-repo/semantics/publishedVersio

    Carbon storage in cacao (Theobroma cacao) plantations in Armero-Guayabal (Tolima, Colombia)

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    P?ginas 6-10El cambio clim?tico sigue siendo la principal amenaza de la humanidad hoy en d?a. Esta problem?tica se ha incrementado debido a las acciones humanas, como el uso de combustibles f?siles, la deforestaci?n y la degradaci?n. La comunidad mundial organizada ha establecido esquemas para mitigar este problema ambiental, por ejemplo el mecanismo de desarrollo limpio. Los sistemas agroforestales con cacao son considerados como mitigadores del cambio clim?tico por capturar carbono en biomasa, necromasa y suelos. Se estim? el almacenamiento y la fijaci?n de carbono en biomasa arriba del suelo y necromasa de cacaotales de 18 y 35 a?os de edad en el Centro Universitario Regional del Norte, en Armero-Guayabal (Tolima, Colombia) CURDN. Los cacaotales estudiados almacenaron 28.8 y 33.6 t C ha-1 en biomasa arriba del suelo a los 18 y 35 a?os, respectivamente, que arrojaron una tasa de fijaci?n promedio de 1.1 t C ha-1 a?o-1 . El carbono almacenado en necromasa ascendi? a 4.4 t ha-1 , con diferencias leves entre las edades de las plantaciones. Los sistemas agroforestales con cacao en Armero-Guayabal (Tolima, Colombia) tienen potencial para mitigar el cambio clim?tico al capturar carbono en biomasa y necromasa.ABSTRACT. Climate change holds as the current main threat of the humankind. This problem has being increasing by human actions such as the use of fossil fuels, deforestation and degradation. The organized world community has established schemes to mitigate this environmental problem, such as the Clean Development Mechanism. Agroforestry systems with cacao are considered as mitigating activities of climate change due to their capture of carbon in biomass and necromass. The carbon storage and fixation in aboveground biomass and necromass in cacao plantations of 18 and 35 years in the Centro Universitario Regional del Norte (CURDN), in ArmeroGuayabal (Tolima, Colombia) were estimated. The studied cacao plantations stored 28.8 and 33.6 t C ha-1 in aboveground biomass with an age of 18 and 35 years respectively, showing an average fixation rate of 1.1 t C ha-1 year-1 . The stored carbon in necromass was 4.4 t ha-1 , with slight differences between the ages of plantations. Agroforestry systems with cacao in Armero-Guayabal, Tolima, Colombia have the potential to mitigate climate change due its capture of atmospheric carbon in aboveground biomass and necromass

    Endothelial Wall Thickness, Cardiorespiratory Fitness And Inflammatory Markers In Obese And Non-obese Adolescents.

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    Increased carotid intima-media thickness (c-IMT) is considered a marker of early-onset atherosclerosis and it has been found in obese children and adolescents, but the risk factors associated with this population remain to be elucidated. To compare and verify the relationship between c-IMT, metabolic profile, inflammatory markers, and cardiorespiratory fitness in obese and non-obese children and adolescents. Thirty-five obese subjects (19 boys) and 18 non-obese subjects (9 boys), aged 10-16 years, were included. Anthropometry, body composition, blood pressure, maximal oxygen consumption (VO2max), and basal metabolic rate were evaluated. Serum glucose, insulin, homeostasis model assessment of insulin resistance (HOMA-IR), blood lipids, C-reactive protein (CRP), and adiponectin were assessed. c-IMT was measured by ultrasound. The results showed that c-IMT, triglycerides, insulin, HOMA-IR, and CRP values were significantly higher in the obese group than in the non-obese group, and high-density lipoprotein cholesterol (HDL-c), adiponectin, and VO2max values were significantly lower in the obese group than in the non-obese group. The c-IMT was directly correlated with body weight, waist circumference, % body fat, and HOMA-IR and inversely correlated with % free fat mass, HDL-c, and VO2max. Our findings show that c-IMT correlates not only with body composition, lipids, insulin resistance, and inflammation but also with low VO2max values in children and adolescents.1847-5
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