L-Lactic Acid Production by Lactobacillus rhamnosus

Lactic acid has been shown to have the most promising application in biomaterials as poly(lactic acid). L. rhamnosus ATCC 10863 that produces L-lactic acid was used to perform the fermentation and molasses was used as substrate. A solution containing 27.6 g/L of sucrose (main composition of molasses) and 3.0 g/L of yeast extract was prepared, considering the final volume of 3,571 mL (14.0% (v/v) inoculum). Batch and fed batch fermentations were performed with temperature of 43.4°C and pH of 5.0. At the fed batch, three molasses feed were applied at 12, 24, and 36 hours. Samples were taken every two hours and the amounts of lactic acid, sucrose, glucose, and fructose were determined by HPLC. The sucrose was barely consumed at both processes; otherwise the glucose and fructose were almost entirely consumed. 16.5 g/L of lactic acid was produced at batch and 22.0 g/L at fed batch. Considering that lactic acid was produced due to the low concentration of the well consumed sugars, the final amount was considerable. The cell growth was checked and no substrate inhibition was observed. A sucrose molasses hydrolysis is suggested to better avail the molasses fermentation with this strain, surely increasing the L-lactic acid

Mass and heat integration in ethanol production mills for enhanced process efficiency and exergy-based renewability performance

This paper presents the process design and assessment of a sugarcane-based ethanol production system that combines the usage of both mass and heat integration (pinch analysis) strategies to enhance the process efficiency and renewability performance. Three configurations were analyzed: (i) Base case: traditional ethanol production (1G); (ii) mass-integrated (1G2G); and (iii) mass and heat-integrated system (1G2G-HI). The overall assessment of these systems was based on complementary approaches such as mass and mass-heat integration, energy and exergy analysis, exergy-based greenhouse gas (GHG) emissions, and renewability exergy criteria. The performances of the three cases were assessed through five key performance indicators (KIPs) divided into two groups: one is related to process performance, namely, energy efficiency, exergy efficiency, and average unitary exergy cost (AUEC), and the other one is associated to environmental performance i.e., exergy-based CO2-equation emissions and renewability exergy index. Results showed a higher exergy efficiency of 50% and the lowest AUEC of all the systems (1.61 kJ/kJ) for 1G2G-HI. Furthermore, the destroyed exergy in 1G2G-HI was lower by 7% and 9% in comparison to the 1G and 1G2G cases, respectively. Regarding the exergy-based GHG emissions and renewability performance (lambda(index)), the 1G2G-HI case presented the lowest impacts in terms of the CO2-equivalent emissions (94.10 gCO(2)-eq/MJ products), while lambda(index) was found to be environmentally unfavorable (lambda = 0.77). However, lambda(index) became favorable (lambda > 1) when the useful exergy of the byproducts was considered710sem informaçãosem informaçã

Efeitos de mudanças de propriedade sobre os processos intraorganizacionais de aprendizagem

This article aims to verify the impact of the change of ownership on the functional strategies associated with intraorganizational processes of technological learning (PIOATs). Based on evidences from the literature showing a relationship between competitive and functional strategies with the nature and concentration of ownership, a case study was conducted in a multinational company taken over by a state-owned company, and it examined how this change affected the PIOATs, from the comparison of time prior to integration and the 17 months following that event. The processes of learning identified in the company (acquisition of internal and external knowledge, and mechanisms of socialization and codification) were identified under acquisition and its conversion throughout the organization and its trajectory examined based on the categories proposed by Figueiredo (2001), variety, intensity, operation and interaction. The results showed that changing the structure of ownership has not worked as a stimulus for maintenance, growth or even emergence of other significant processes in the company. Key words: technological learning processes, ownership structure, corporate governance.Este artigo objetiva verificar os impactos da mudança de propriedade sobre as estratégias funcionais associadas aos Processos Intraorganizacionais de Aprendizagem Tecnológica (PIOATs). A partir de evidências da literatura que apontam a relação das estratégias competitivas e funcionais com a natureza e concentração da propriedade, primeiro, realizou-se um estudo de caso em uma empresa multinacional adquirida por uma empresa estatal nacional e, segundo, analisou-se como essa mudança afetou seus PIOATs, a partir da comparação entre momento anterior à incorporação e os quase 17 meses seguintes a esse evento. Identificaram-se os processos de aprendizagem de acordo com a aquisição de conhecimentos e a conversão organizacional; analisaram-se essas trajetórias segundo a categorização proposta por Figueiredo (2001), a saber: variedade, intensidade, funcionamento e interação. Os resultados evidenciaram que, no período analisado, a mudança da estrutura de propriedade não funcionou como estímulo à manutenção do crescimento nem para surgimento de outros processos significativos na empresa. Palavras-chave: processos de aprendizagem tecnológica, estrutura de propriedade, governança corporativa

Efeitos de mudanças de propriedade sobre os processos intraorganizacionais de aprendizagem

This article aims to verify the impact of the change of ownership on the functional strategies associated with intraorganizational processes of technological learning (PIOATs). Based on evidences from the literature showing a relationship between competitive and functional strategies with the nature and concentration of ownership, a case study was conducted in a multinational company taken over by a state-owned company, and it examined how this change affected the PIOATs, from the comparison of time prior to integration and the 17 months following that event. The processes of learning identified in the company (acquisition of internal and external knowledge, and mechanisms of socialization and codification) were identified under acquisition and its conversion throughout the organization and its trajectory examined based on the categories proposed by Figueiredo (2001), variety, intensity, operation and interaction. The results showed that changing the structure of ownership has not worked as a stimulus for maintenance, growth or even emergence of other significant processes in the company. Key words: technological learning processes, ownership structure, corporate governance.Este artigo objetiva verificar os impactos da mudança de propriedade sobre as estratégias funcionais associadas aos Processos Intraorganizacionais de Aprendizagem Tecnológica (PIOATs). A partir de evidências da literatura que apontam a relação das estratégias competitivas e funcionais com a natureza e concentração da propriedade, primeiro, realizou-se um estudo de caso em uma empresa multinacional adquirida por uma empresa estatal nacional e, segundo, analisou-se como essa mudança afetou seus PIOATs, a partir da comparação entre momento anterior à incorporação e os quase 17 meses seguintes a esse evento. Identificaram-se os processos de aprendizagem de acordo com a aquisição de conhecimentos e a conversão organizacional; analisaram-se essas trajetórias segundo a categorização proposta por Figueiredo (2001), a saber: variedade, intensidade, funcionamento e interação. Os resultados evidenciaram que, no período analisado, a mudança da estrutura de propriedade não funcionou como estímulo à manutenção do crescimento nem para surgimento de outros processos significativos na empresa. Palavras-chave: processos de aprendizagem tecnológica, estrutura de propriedade, governança corporativa

Principal component analysis on recurrent venous thromboembolism

The rates of recurrent venous thromboembolism (RVTE) vary widely, and its causes still need to be elucidated. Statistical multivariate methods can be used to determine disease predictors and improve current methods for risk calculation. The objective of this study was to apply principal component analysis to a set of data containing clinical records of patients with previous venous thromboembolism and extract the main factors that predict recurrent thrombosis. Records of 39 factors including blood and lipid parameters, hereditary thrombophilia, antiphospholipid syndrome, clinical data regarding previous thrombosis and treatment, and Doppler ultrasound results were collected from 235 patients. The results showed that 13 principal components were associated with RVTE and that 18 of 39 factors are the important for the analysis. These factors include red blood cell, white blood cell, hematocrit, red cell distribution width, glucose, lipids, natural anticoagulant, creatinine, age, as well as first deep vein thrombosis data (distal/proximal, d-dimer, and time of anticoagulation). The results demonstrated that simple clinical parameters easy to be collected can be used to predict rates of recurrence and to develop new clinical decision support systems to predict the rates of RVTE25FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP2016/14172-6The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: Funded by Fundac¸a˜o de Amparo `a Pesquisa do Estado de Sa˜o Paulo (FAPESP). Process number: 2016/14172-

Multivariable nonlinear advanced control of copolymerization processes

A reliable multivariable model of a process is a fundamental prerequisite for the design of an efficient control strategy. Though, such a model is often very hard to obtain via a first-principles approach. The development of two fuzzy model-based multivariable nonlinear predictive control schemes and their implementation on a copolymerization process are described in this paper. Multi-input/single-output models are developed using fuzzy logic and combined to form a parallel system model for simulation and online prediction. The behavior of the outlined controllers were compared to the dynamic matrix control (DMC) and to a typical nonlinear model-based predictive control (NMPC) for regulatory problem and the obtained results showed the effectiveness of the proposed structures

Butanol production in a first-generation Brazilian sugarcane biorefinery: Technical aspects and economics of greenfield projects

AbstractThe techno-economics of greenfield projects of a first-generation sugarcane biorefinery aimed to produce ethanol, sugar, power, and n-butanol was conducted taking into account different butanol fermentation technologies (regular microorganism and mutant strain with improved butanol yield) and market scenarios (chemicals and automotive fuel). The complete sugarcane biorefinery with the batch acetone–butanol–ethanol (ABE) fermentation process was simulated using Aspen Plus®. The biorefinery was designed to process 2million tonne sugarcane per year and utilize 25%, 50%, and 25% of the available sugarcane juice to produce sugar, ethanol, and butanol, respectively. The investment on a biorefinery with butanol production showed to be more attractive [14.8% IRR, P(IRR>12%)=0.99] than the conventional 50:50 (ethanol:sugar) annexed plant [13.3% IRR, P(IRR>12%)=0.80] only in the case butanol is produced by an improved microorganism and traded as a chemical

Redundant VoD Streaming Service in a Private Cloud: Availability Modeling and Sensitivity Analysis

For several years cloud computing has been generating considerable debate and interest within IT corporations. Since cloud computing environments provide storage and processing systems that are adaptable, efficient, and straightforward, thereby enabling rapid infrastructure modifications to be made according to constantly varying workloads, organizations of every size and type are migrating to web-based cloud supported solutions. Due to the advantages of the pay-per-use model and scalability factors, current video on demand (VoD) streaming services rely heavily on cloud infrastructures to offer a large variety of multimedia content. Recent well documented failure events in commercial VoD services have demonstrated the fundamental importance of maintaining high availability in cloud computing infrastructures, and hierarchical modeling has proved to be a useful tool for evaluating the availability of complex systems and services. This paper presents an availability model for a video streaming service deployed in a private cloud environment which includes redundancy mechanisms in the infrastructure. Differential sensitivity analysis was applied to identify and rank the critical components of the system with respect to service availability. The results demonstrate that such a modeling strategy combined with differential sensitivity analysis can be an attractive methodology for identifying which components should be supported with redundancy in order to consciously increase system dependability

Polymeric Separator Synthesis for Lithium-Air Batteries

Battery electricity storage has been one of the main strategies to reach a sustainable energy network. They are adequate to store energy and release it later, supporting a high volume of variable renewable electricity. In this context, lithium-air batteries (LABs) have the potential to be a high-capacity battery option, with theoretical energy densities higher than currently available lithium-ion ones. However, they are still commercially unfeasible. In the last few decades, there has been immense progress in LABs technology with the development of stable electrolytes, porous cathodes, and catalysts. Nonetheless, minor attention has been given to the protection of the lithium metal electrode, especially against reactive substances present in the atmospheric air, such as water and oxygen. In this work, a protective membrane was synthesized to protect the metallic lithium anode against water. The synthesis was carried out using polytetramethylene glycol (PTMEG), 4,4-diphenylmethane diisocyanate (MDI), and a blend of 1,4 butanediol with glycerine as a chain extender. The synthesized membrane was tested using an aprotic lithium-oxygen (Li-O2) battery assembled with carbon paper as the cathode, metallic lithium as the anode, and 0.1 mol.L-1 lithium perchlorate (LiClO4) in dimethyl sulfoxide (DMSO) with 550 ppm of water concentration as electrolyte. Furthermore, the cyclability of the batteries with the novel polymeric membrane was compared with the standard glass microfiber separator. The results showed a higher cyclability of the batteries assembled with the polymeric separator over the glass microfiber separator.</p