Navegando por Data de Publicação, começando com "2019-05-10"

Filtrar resultados por ano ou mês

Agora exibindo 1 - 6 de 6

Design and automation of a new reactor for enzymatic hydrolysis of lignocellulosic biomass at high solids loading
(Universidade Federal de São Carlos, 2019-05-10) Furlong, Vitor Badiale; Giordano, Roberto de Campos; https://lattes.cnpq.br/0834668419587001; Ribeiro, Marcelo Perencin de Arruda; https://lattes.cnpq.br/0381402687491195; https://lattes.cnpq.br/5013148190194235
Several bottlenecks need to be overcome in order to establish the biorefinery concept as a feasible and lucrative second generation ethanol production technology. Lignocellulosic biomass enzymatic saccharification presents itself as one of the major challenges. This process needs high productivity while retaining low cost in order to become a regular practice. However, high enzymatic cocktail cost and complex phenomena makes its optimization a difficult task. Different strategies are necessary to deal with this task. In this work, different research fronts have been explored to improve the sugarcane bagasse enzymatic hydrolysis process performance. To improve modeling, a Fuzzy reaction rate model was proposed. Aiming to improve hydrolysis state prediction, specially under fed-batch conditions. This methodology proved to be useful in this situation, improving prediction both in training and validation assays. This model was coupled to a state estimator to enable monitoring of the hydrolysis process in real time. To do such, a Moving Horizon Estimator was implemented, and instrumentation data was obtained from a soft-sensor using an Artificial Neural Network to predict solids concentration from the reactor’s mixing power requirement. This algorithm was able to predict the desired state variables, however, further studies are necessary before online implementation. Another research front explored in this work was the design of a new reactor architecture. A Semisolid Horizontal Saccharification Bioreactor was developed and coupled to a stirred reactor to compose a parallel reactor system. An automated solids feeder and liquid autosampler were also developed. These apparatus improved energy consumption of the process, while retaining performance indexes from other architectures. The development of the new reactor architecture opens new technologies possibilities inside the bioethanol biorefinery.
Modelos série de potência zero-modificado para séries temporais com dados de contagem
(Universidade Federal de São Carlos, 2019-05-10) Shirozono, Aimée; Conceição, Katiane Silva; https://lattes.cnpq.br/5789619620619667; Andrade Filho, Marinho Gomes de; https://lattes.cnpq.br/4126245980112687; https://lattes.cnpq.br/1158155125122366
The goal of this work is to propose the Zero-Modified models with Power Series distribution (ZMPS) for time series with counting data. The ZMPS model have a huge portfolio of count data distributions wherein, with an appropriate link function, we can write the regression models using the ZMPS distributions similar to what is done with generalized linear models. Then, we can use the idea of the Generalized Autoregressive and Moving Average (GARMA) models to propose the Zero-Modified Power Series models for Time Series with counting data.
Comparação de ciclagem de nutrientes em pastagens convencionais, sistemas silvipastoris e floresta estacional semidecídua
(Universidade Federal de São Carlos, 2019-05-10) Marcondelli, Ana Carolina Buzzo; Nicodemo, Maria Luiza Franceschi; https://lattes.cnpq.br/4892401475655718; Matos, Dalva Maria da Silva; https://lattes.cnpq.br/4728734263109138; https://lattes.cnpq.br/5197686322570850
Silvopastoral systems combine trees, pastures and livestock. Cattle production systems cause fewer ecosystem effects compared to conventional pasture systems. The cycle of organic capacity has an essential role, once that integrated the biogeochemical cycles, which are the following cycle of elements and energy between the environment and the organisms. The litter is of fundamental importance for the transfer of nutrients to the system, with much of the nutrients absorbed by the vegetation to the soil through its deposition. The decomposition of litter is one of the main ways of filling organic and inorganic fields for the processes of nutrient control and control of return to the system. The objective of this work was to compare and analyze the decomposition of litter and its nutrients in production systems with the monoculture of grasses and grasses + trees, using a semideciduous seasonal forest as a control. For litter collection, three replicates of samples collected monthly for 12 months, through collectors 0.5 m x 0.5 m. In the case of the Urochloa litter, non-fallen senescent material was collected alone, in 0.5 m x 0.5 m frames. The dry matter, organic matter, carbon, lignin, cellulose, macro and micronutrients elements were analyzed both in the dry season and in all systems. For the decomposition study, senescent leaves with no sign of decomposition were collected in each of the systems. Then, 10 g of dried leaves were packed in nylon bags, measuring 25 cm x 25 cm, 2 mm thick, steel at 60 ° C for 72 hours and finally weighed. Later, these pockets were made on a litter accumulated in the soil. The degradation rate, done in six periods, in dry season: 0, 4, 8, 16, 32, 64 and 128 days, with three replicates each, being withdrawn and weighed at the end of each year and taken to nutrient analysis. There was no significant difference in litter between the production systems, however, the greater existential support in pastures with native trees, demonstrating that the larger systems of greater availability of nutrients to the soil. It was not different between the systems in relation to the decomposition process, being greater only in the forest. The production of nutrition, we conclude that pastoral systems with native species the soil tends to be richer, reducing the impact of livestock.
O lugar do ensino de ciências na escolha da carreira universitária de jovens negros
(Universidade Federal de São Carlos, 2019-05-10) Souza, Milena de; Silva, Douglas Verrangia Corrêa da; https://lattes.cnpq.br/7699024298055259; https://lattes.cnpq.br/6687376315564427
The purpose of this study was to understand the relationship between school science education and the choice of university career, taking into account the ethnic-racial cohort, and identifying the place of science education in the choice of the career of young people, in view of this cohort. In order to reach the proposed goal, it was necessary to characterize the vision of this research subjects on science education, to know their life projects and their career choices, and to identify the possible relationships between the vision of science teaching and the developments in this choice. Thus, it was decided to use a methodological clipping that would allow the participants to reflect on their school experiences and their possible career choices, and the researcher, the interpretation of the meaning relations. The research was developed with students of the pre-university course of the Federal University of São Carlos, and had as methodological consisted of a questionnaire with multiple-choice question in order to know general data, life project characteristics and career pretensions of the participants; and a focus group, where the discussions initially presented in this paper were shared, in order to verify the hypotheses generated by the group. Based on the data analysis, inspired by the phenomenological method of Merleau Ponty (1989), and based on the participants, units of meaning that relate to career choice were identified. Analyzing these units of meanings, it was noticed that there are two dimensions with which subjects and career are connected: internal dimension that includes the factors that arise from the internal conditions of the individual; and external dimension that refers to the factors that relate to the culture, class and aspects of the individual's social context. Based on these dimensions, four factors were identified that relate to career choice: the aptitude, the teacher, the school subjects and the family. Thus, it was possible to conclude that science education does not have a special place in career choice, it is involved in a larger set of circumstances, from aptitude to social context, involving the affinity that the young person establishes with the teacher himself/herself and his/her qualification the view they have of themselves from the learning verifications developed in the school environment, and the overlap between the contents, the identity of the teacher and the work of the scientist. Such circumstances reflect part of the interaction that individuals make with the world, and thus relate to the creation of the life project of these young people. Therefore, with the results found, it is hoped to highlight the importance that schooling, and especially science education, deal with the life project of young people a more profound and explicit way, leading them to reflect significantly on their positioning regarding their choices, and the distortions demarcated by racial and ethnic dimensions.
Produção de bambu laminado colado: propriedades e aplicações
(Universidade Federal de São Carlos, 2019-05-10) Santos, Thiago Oliveira dos; Barbosa, Juliana Cortez; https://lattes.cnpq.br/8172590572025942; Rubert, José Benaque; https://lattes.cnpq.br/1726311467903505; https://lattes.cnpq.br/5203557380299048
This paper is a contribution to the process and usage development of bamboo as a raw material as a sustainable practice in several Brazilian economic fields, with emphasis on civil construction. The processed bamboo is used in the manufacture of glued laminates, designated as BLC, Bamboo Laminate Glued, is the object of object study. BLC beams were made using the plants Phyllostachys pubescens and Dendrocalamus giganteus, and with the usage of the Polyurethane Bicomponent and Monocomponent adhesives. Standardized specimens were prepared for the physical and mechanical characterization with obtained results compatible with other species mentioned in literature. Bamboo blades were then produced for the manufacture of BLC beams. The beams produced were submitted to the control of the glue quality (glue line resistance, and delamination) and to the static bending test in order to evaluate the rupture modes and to compare the experimental rigidity with the theoretical model. The results of the glue quality test ranged between 25.59 to 55% at the delamination test, and the results figured between 4.66 and 6.69% at the glue line resistance test. The rigidity was compared following standard ABNT NBR 7190: 2013 expression. The differences between the experimental and theoretical rigidity in BLC produced with bamboo P. pubescens and Polyurethane Bicomponent and Monocomponent adhesives were around 20.41 and 5.00%, respectively. In the BLC beams produce with D. giganteus bamboo this difference between rigidities was around 11% for both types of adhesives.
Ativação da GCs no endotélio como estratégia para reverter e/ou prevenir a disfunção endotelial
(Universidade Federal de São Carlos, 2019-05-10) Martinelli, Ariane Migliato; Rodrigues, Gerson Jhonatan; https://lattes.cnpq.br/6725550216586910; https://lattes.cnpq.br/3110739864735199
Introduction: The vascular endothelium presents an important protective function against cardiovascular diseases, and the release of NO has a central role in this protection. Reduction of NO bioavailability and decreased sensitivity of sGC to NO are well recognized in endothelial dysfunction. Although the underlying mechanisms of endothelial dysfunction are multifactorial, the main cause is an NO / sGC / cGMP pathway. Therefore, sGC is an important pharmacological target, which can lead to the development of key drugs in the control and treatment of hypertension, heart failure, among others. In this sense, the objective of this work was to evaluate the accumulation of cGMP in the endothelium as a strategy to revert and / or prevent endothelial dysfunction by means of the soluble guanylate cyclase activator ataciguat. Methods: Aortic rings of male Wistar rats with and without endothelium were placed in a myograph and concentration-cumulative effect curves for ataciguat were performed. In addition, intact aortic rings of normotensive (2K) and hypertensive (2K-1C) rats were incubated with ataciguat and cumulative concentration curves for acetylcholine (Ach) were measured to measure endothelial function. In addition, nitric oxide (NO) was measured by fluorescence or selective electrode on human umbilical endothelial cells (HUVECs) in response to some treatments, including ataciguat, 8-Br-cGMP and A23187. Detection of Reactive Oxygen Species (ROS) and superoxide anion (O2-) were performed using fluorescent probes, including DHE and lucigenin. Results: The presence of endothelium enhanced the ataciguat-induced relaxation in the aortic rings. In the presence of the nitric oxide synthase inhibitor (NOS), the endothelium effect was abolished. Treatment of the aortic rings with ataciguat improved the acetylcholine-induced relaxation in 2K-1C and 2K vessels. In the endothelial cell culture, treatment with ataciguat (0.1, 1 and 10 μM) decreased angiotensin II-induced superoxide anion formation. In addition, ataciguat, 8-Br-cGMP and A23187 were able to induce NO production in HUVECs. In the presence of the NOS inhibitor, the NO production induced by ataciguat and 8-Br-cGMP was abolished. Conclusion: Our results suggest that the activation of sGC in endothelial cells induces the production of NO by a mechanism dependent on the activation of NOS and decrease of O2-, with consequent potentiation of vascular relaxation dependent on the endothelium.