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Otimização do controle do oxigênio dissolvido em biorreator airlift pressurizado: aplicação em cultivos de Escherichia coli recombinante
(Universidade Federal de São Carlos, 2018-01-12) Campani Junior, Gilson; Ribeiro, Marcelo Perencin de Arruda; https://lattes.cnpq.br/0381402687491195; Zangirolami, Teresa Cristina; https://lattes.cnpq.br/4546701843297248; https://lattes.cnpq.br/1982252146006688
A wide variety of industrial and therapeutic proteins is synthetized by genetically modified Escherichia coli, which is ease to cultivate and manipulate and also well characterized. However, there are only few studies regarding E. coli cultivation in the pneumatic airlift bioreactor. This reactor presents some advantages over the stirred tank, such as simpler construction, lower risk of contamination, and efficient gas-liquid dispersion with reduced power consumption. However, the lower oxygen transfer capacity in the bench-scale airlift bioreactor, in comparison to the stirred tank, justifies the use of temperature, pressure, and gas and oxygen flow rates as manipulated variables for the dissolved oxygen (DO) control. In this context, this thesis aims: (i) to develop a mathematical model that describes the production of the Pneumococcal Surface Protein A (PspA) by recombinant E. coli in a pressurized airlift reactor, taking into account oxygen transfer and uptake in the process; (ii) to perform economic optimization of the DO control; (iii) to develop an advanced DO controller integrated to state estimators. Data of E. coli cultivation in conventional and airlift reactors were used to identify and validate the models. The dynamic optimization was performed using a gradient method based on the Pontryagin's minimum principle. The developed mathematical models were able to describe the process under varying conditions of temperature and pressure. The dynamic optimization of the DO control resulted in a simple and sequential way of handling the inputs: manipulation of air flow rate, followed by system pressurization, and then air enrichment with pure oxygen. The optimum process temperature was 27 °C. A model predictive DO control was then proposed, associated to two state estimators, the extended Kalman filter (EKF) and the moving horizon estimator (MHE). They were both able to estimate satisfactorily four state variables (cell, substrate, PspA, and DO concentrations) based only on DO measurements. The control system proved to be robust in process simulations. The conclusions that arise from this thesis contribute to the area of development of non-conventional reactors and DO controllers, especially for pneumatic bioreactors, which are widely used in aerobic bioprocesses.
Análise temporal do processo de ocupação dos vazios urbanos no município de São Carlos, SP : sob a ótica de uma cidade compacta
(Universidade Federal de São Carlos, 2018-01-12) Barbosa, Yanayne Benetti; Gonçalves, Luciana Márcia; https://lattes.cnpq.br/9491069760631962; Lollo, José Augusto de; https://lattes.cnpq.br/8987677644041247; https://lattes.cnpq.br/0106501285091187
In this work, the mapping and analysis of the urban voids of São Carlos (SP), through GIS, showed the spatial dynamics through the valorization and or depreciation that urban areas present. The objective of this study was to analyze the the urban voids in different urban areas (established by the Plano Director) considering the years 2004 and 2014, in the municipality of São Carlos, SP. As a result, we highlight the detailed characterization of the historical series of land value in the urban voids and surroundings in the last twenty years. In addition, it is proposed a scenario that made it possible to simulate occupation that resulted in almost 40 thousand inhabitants in urban voids, maintaining the profile of occupancy and densification in urban zoning. Inside the new limit and rules of the 2016 Plano Diretor, the occupation of urban voids may promote, in addition to the occupation, a greater density, without need to increase the urban perimeter to fulfill the social function of the use of urban land, thus reducing the costs of deploying new urban infrastructure
Efeito de pausas ativas e passivas e da variação de ritmo de trabalho na atividade eletromiográfica e oxigenação de músculos escapulotorácicos em mulheres com e sem dor no pescoço-ombro durante a realização de uma tarefa manual repetitiva.
(Universidade Federal de São Carlos, 2018-01-12) Januário, Letícia Bergamin; Oliveira, Ana Beatriz de; https://lattes.cnpq.br/1049547759186556; https://lattes.cnpq.br/4211382316214060
The main objective of this PhD thesis was to evaluate the effects of including active pauses and changing work pace on the neck-shoulder region of women during a repetitive simulated industrial task, considering the measurements of surface electromyography, muscle oxygenation and 2D kinematics. This research was based on four studies: (Study 1) the synthesis of the methods used to apply and analyze the active pauses during the performance of monotonous, repetitive and static tasks, through a systematic review; (Study 2) the investigation of the effects of active and passive pauses and the implementation of different work paces on the electromyographic activity (EMG) of trapezius and anterior serratus muscles during a repetitive task performed by women without musculoskeletal symptoms on the neck- shoulder region; (Study 3) the evaluation of the effects of active and passive pauses, on upper trapezius muscle oxygenation and upper body posture, considering a single work pace and comparing women with and without neck-shoulder pain; and finally (Study 4) the investigation of implementing different work paces on the functional connectivity from muscles of the scapulothoracic region during the performance of a repetitive task performed by women with and without musculoskeletal symptoms on the neck-shoulder region. The literature review included 15 studies and found that active pauses were partially able to change the EMG level during monotonous activities to a more beneficial pattern of muscle activity. However, the synthesis of evidence was limited and the results should be considered with caution. On the other studies (2-4), the experimental procedure used to evaluate the active pauses and the implementation of different work pace in an experimental setting was based on a standard, repetitive, monotonous and assembly-like task. We evaluated women with and without chronic pain in the neck-shoulder region in terms of EMG of acromial and clavicular portions of the upper trapezius, middle trapezius, lower trapezius and anterior serratus muscles; (b) upper trapezius muscle oxygenation; (c) posture of head, trunk and arm. The Study 2 pointed out that contrary to the hypothesis raised, no interaction between work pace and pause type was found. The slow pace resulted in an acute decrease in biomechanical exposure in terms of EMG and more variation in the activation pattern of scapulothoracic muscles when compared to the same task performed at fast pace. Considering the types of pauses applied, no significant difference was found between passive and active pauses, contrary to previous studies, except that the active pauses resulted in an increased EMG activation level in the clavicular portion of the upper trapezius. Study 3 reveled that active pauses are capable of promoting an increase in muscle oxygenation of the dominant upper trapezius and also modifying the postures of head, upper trunk and arm during a repetitive assembly task, but unlike hypothesized women with and without neck-shoulder pain had similar results in terms of oxygenation and postures of the upper body region. Study 4 revealed that contrary to our hypothesis, the groups with and without neck-shoulder pain had similar electromyographic patterns in terms of EMG amplitude, muscular rest level and functional connectivity. When comparing paces, it was possible to observe that the fast movement pace imposed a greater biomechanical load, evidenced by higher amplitude EMG, lower degree of muscular rest and higher level of functional connectivity in comparison to the slow pace. Generally, we can conclude that the proposed interventions did not interact between themselves and that no significant differences between women with and without neck-shoulder pain were found in terms of EMG, oxygenation and posture. The slow pace led to a higher variation and lower functional connectivity of the scapulothoracic muscles, which indicates a decrease on the biomechanical load of this region. The active pauses pointed out towards benefits in terms of muscle oxygenation and upper body posture, even though no significant differences were found in terms of EMG when compared with passive pauses.