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Obten??o do Ricinoleato de D-glicose e sua aplica??o em fluidos de perfura??o / D-Glucose Ricinoleate and its apllications in drilling fluidsMedeiros, Suzan Ialy Gomes de 04 September 2012 (has links)
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Previous issue date: 2012-09-04 / Enzimas t?m sido largamente utilizadas em bioss?ntese para transforma??es
de compostos org?nicos em substitui??o aos m?todos sint?ticos cl?ssicos. Este
trabalho descreve a s?ntese enzim?tica de biossurfactantes a partir da Dglicose
com ?cido ricinol?ico empregando como biocatalisador a protease de
Bacillus subtillis alcalina. Com aux?lio do software MODDE 7.0, o planejamento
experimental utilizando um modelo fatorial 2 4-1 (planejamento reduzido de 2
n?veis e 4 vari?veis) foi realizado para verificar a influ?ncia das vari?veis
temperatura, tempo de rea??o, concentra??o de enzima e raz?o molar do
substrato/D-glicose sobre o rendimento da rea??o. An?lises de espectroscopia
na regi?o do infravermelho (FTIR) confirmaram a forma??o do produto atrav?s
de absor??es em 3400 cm-1, caracter?stica das hidroxilas presentes no anel do
a??car, e em 1739 cm-1, correspondente ? carbonila de ?ster. As an?lises de
CLAE (cromatografia l?quida de alta efici?ncia) mostraram as taxas de
convers?es alcan?adas pelo biocatalisador protease de Bacillus subtillis
alcalina. Medidas de tens?o superficial em diferentes condi??es, foram
realizadas com o produto de rea??o, onde observou-se redu??o da tens?o
superficial da ?gua de 72 mN/m para 33 mN/m. Foi poss?vel verificar tamb?m a
estabilidade quanto do produto frente as solu??es salinas (115 g/L), nas
solu??es tamp?o com pH extremos de 2 ? 12 e em solu??es aquosas
aquecidas no intervalo de 25 a 100 ?C. Visando aplica??o do produto em
t?cnicas Core-Flow (transporte de ?leo), an?lises de ?ngulo de contato pelo
m?todo da placa de Willemy foram realizadas, obtendo-se a redu??o do ?ngulo
de contato, do vidro com ?gua, de 40? para 0?. Nas an?lises como lubrificante e
redutor de filtrado em fluidos de perfura??o polim?ricos observou-se, nas v?rias
formula??es, que a mistura biodiesel/biossurfactante apresentou resultados
satisfat?rios reduzindo o CL (coeficiente de lubricidade) em 87% e o volume de
filtrado em 22%. Nos testes de forma??o e estabilidade de espuma,
caracter?stica que deve ser evitada por proporcionar leituras incorretas (peso espec?fico, reologia, volumetria, etc), nenhum dos biossurfactantes teve a??o
espumante caracterizando seu bom desempenho. / Enzymes have been widely used for organic compounds biosynthesis,
attracting a great deal of attention in recent years, due to its several advantages
over the chemical method. This work describes the enzymatic synthesis of
biosurfactants from d-glucose with ricinoleic acid using proteases Bacillus
subtillis alcalina as biocatalysts. Aiming to reach high conversions from
substrates to products for a possible future large scale industrial production, a
serie of variables was optimized, through MODDE 7.0, using the factorial model
design 24-1. The investigated variables were: temperature, reaction time,
enzyme concentration and substrate/D-glicose rate. Qualitative analysis by
infrared spectroscopy (FTIR) confirmed the product formation through
characteristic peaks due to hydroxyl group absorption on the sugar ring at 3400
cm-1 and the carbonyl group at 1739 cm-1, which refers to ester carbonyl. HPLC
analysis (High Performance Liquid Chromatography) showed higher
conversions using of alkaline protease of Bacillus subtillis. Besides, it was
observed that all the biosurfactants reduced the surface tension of water from
72 to 33 mN/m (by interpolate of the plate method). According to surface
tension results, it was possible to evaluate the stability of each product about
saline (maximum 115g/L) and buffer solutions (pH 2 ? 12), from a temperature
range from 25 to 100?C). Aiming its application to core-flow technique, contact
angle measurements presented reduction of 40? to 0? in presence of d-glucose
ricinoleate, when compared to distillated water. Different applications of this
product were investigated, such as: lubricant and filter loss control for polymeric
drilling fluids of petroleum wells. It was observed the reduction of lubricity
coefficient and filtrate loss control in 87 and 22 %, respectively.
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Avalia??o da estabilidade oxidativa e determina??o da cin?tica de oxida??o de ?leos vegetais, ?cido oleico e biodiesel utilizando o m?todo PetroOXY (ASTM D7545)Machado, Yguatyara de Luna 02 July 2014 (has links)
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Previous issue date: 2014-07-02 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / A Ag?ncia Nacional de Petr?leo, G?s Natural e Biocombust?veis tem como principal miss?o regulamentar e especificar toda a produ??o e comercializa??o do biodiesel produzido em territ?rio nacional. Para a sua comercializa??o ? necess?rio que o biodiesel passe por um controle r?gido de qualidade, bem como esteja devidamente especificado pelas principais normas. A estabilidade oxidativa que ? um dos par?metros incluso pela norma europ?ia EN 14214 vem adquirindo cada vez mais espa?o em pesquisas por estar intrinsecamente relacionada ? qualidade do biodiesel. Biodiesel ? uma mistura de ?steres alqu?licos de ?cidos graxos obtido, convencionalmente, atrav?s da rea??o de transesterifica??o de um ?leo vegetal ou gordura animal. No entanto, a natureza da mat?ria-prima a qual lhe dar? origem ? um dos fatores determinantes em seu grau de estabilidade, visto que por apresentarem insatura??es em n?mero e em distintas posi??es os tornam suscept?veis ao ataque do oxig?nio atmosf?rico e a condi??es de elevadas temperaturas proporcionando, assim, a sua degrada??o. Uma das principais problem?ticas enfrentadas, atualmente, pela ind?stria de biodiesel prov?m da sua baixa estabilidade levando a uma diminui??o de sua qualidade por longos per?odos de armazenamento sendo necess?ria a aplica??o de antioxidantes. Nesta tese, um estudo cin?tico experimental baseado no consumo de diferentes antioxidantes sint?ticos adicionados em distintas concentra??es foi realizado com amostras de ?leos vegetais de moringa (Moringa oleifera) e de maracuj? (Passiflora edulis), ?cido ol?ico estocado (AO) durante seis e dezoito meses e biodiesel de soja (Glycine max L.) e girassol (Helianthus annuus) em diferentes temperaturas, a uma press?o de oxig?nio puro a 700 kPa, utilizando a metodologia ASTM D7545 (PetroOXY). O modelo de primeira ordem obtido para o ?leo de moringa, amostras de ?cido ol?ico estocado (AO) e biodiesel de soja permitiu obter informa??es a respeito de par?metros, tais como: concentra??o cr?tica e concentra??o de antioxidante natural inerente ? amostra avaliada , informando que o ?ltimo n?o exerceu influ?ncia, a n?o ser inicialmente, no processo oxidativo das mesmas. Enquanto, o par?metro determinado para o modelo de ordem zero para as amostras de ?leo de maracuj? e girassol relacionou-se a diferentes reatividades da mat?ria-prima. A estabilidade das amostras determinadas pela entalpia de ativa??o (?HA) deu-se na seguinte ordem: ?HA (?leo de moringa) > ?HA (?leo de maracuj?); ?HA (AO 6 meses) ?HA (AO 18 meses) e ?HA (biodiesel de soja) > ?HA (biodiesel de girassol). Fatores de estabiliza??o desempenharam diferentes pap?is na estabiliza??o dos sistemas estudados. Concentra??o de antioxidante e temperatura mostraram distintas influ?ncias, no processo oxidativo, para as amostras de ?leos vegetais e ?cido ol?ico estocadas (AO) acompanhadas pelos seus ?ndices de acidez. / Oxidative stability is a parameter included in the European standard EN 14214 and is closely associated with the quality of biodiesel. The biodiesel is usually obtained in a transterification reaction vegetable oil or animal fat. However, the composition of the raw resources biodiesel is obtained from influences the stability degree of the latter, particularly when biodiesel is stored for long periods of time, causing its degradation, thereby reducing biodiesel quality and making it inadequate for trade. In this thesis, an experimental kinetic study based on the consumption of several synthetic antioxidants added in various concentrations to vegetable oils of moringa (Moringa oleifera), passion fruit (Passiflora edulis) and oleic acid (AO) stored for six and eighteen months at the temperatures 110 ?C, 120 ?C, 130 ?C and 140 ?C, as well as biodiesel from soybean (Glycine max L.) and sunflower (Helianthus annuus) oils at the temperatures 130 ?C, 135 ?C, 140 ?C and 145 ?C at a 700 kPa pure oxygen pressure, using the ASTM D7545 Method (PetroOXY). It has been obtained a first order reaction kinetic model for oleic acid, soybean biodiesel and moringa oil samples, while for passion fruit oil and sunflower biodiesel samples a zero order reaction kinetic model has been obtained. Parameter
0,CICCCC???
determined for the zero order model was related to distinct composition variations of the raw resources. The stability order of samples established using activation enthalpy (?HA) was the following: ?HA (moringa oil) > ?HA (Passion fruit oil); ?HA (oleic acid stored for six months) ? ?HA (oleic acid stored for eighteen months) and ?HA (soybean biodiesel) > ?HA (sunflower biodiesel). In all evaluated temperatures except for 140?C, acid numbers for passion fruit oil with antioxidants added have increased after storage, while for the moringa oil a random behavior has been observed.
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Rela??o da express?o g?nica do ECHDC3 com perfil de ?cidos graxos e fatores nutricionais na doen?a arterial coronarianaDuarte, Mychelle Kytchia Rodrigues Nunes 06 December 2016 (has links)
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Previous issue date: 2016-12-06 / A doen?a arterial coronarina ? uma das principais causa de ?bitos em todo o mundo e pode ser desencadeada por altera??es no perfil s?rico de ?cidos graxos, nos padr?es de express?o g?nica, no consumo alimentar e diet?tico e por desequil?brios antropom?tricos e/ou de composi??o corporal. O diagn?stico precoce desta doen?a ? um desafio na medicina translacional, visto que os m?todos utilizados s?o onerosos e/ou invasivos. O trabalho ent?o teve como objetivo identificar biomarcadores para o diagn?stico precoce da aterosclerose por meio do perfil serico de ?cidos graxos, express?o do RNAm da enoil-coA-hidratase (ECDHC3) e de fatores nutricionais em pacientes sem les?es e com diferentes extens?es da les?o ateroscler?tica. Realizou-se um estudo observacional, com a amostragem coletada por conveni?ncia, formada por pacientes que iriam realizar pela primeira vez a cinecoronariogradia no setor de Hemodin?mica do Hospital Universit?rio Onofre Lopes. Na primeira casu?stica participam 59 pacientes (n1, 2011-2013) e na segunda 41 (n2, 2014-2015), ambos com idade entre 30-74 anos. Determinou-se a extens?o das les?es por meio do ?ndice de Friesinger, o perfil bioqu?mico (glic?mico,lipid?mico) por espectrometria semiautomatizado; concentra??o s?rica de ?cidos graxos pela cromatografia gasosa; express?o do RNAm do ECHDC3 pela rea??o de cadeia de prolimerase (PCR) em tempo real; consumo alimentar e diet?tico por dois recordat?rios de 24h, par?metros antropom?tricos e composi??o corporal pela balan?a com bioimped?ncia el?trica, fita m?trica e estadiometro. Os pacientes foram classificados em grupos: sem les?o (n1=18/n2 =8), poucas les?es (n1=17/n2=6), intermedi?rias (n1=17/n2=15) e graves (n1=7/n2=12). Na primeira casu?stica foi encontrado elevadas concentra??es s?ricas de ?cido ol?ico e de ?cidos graxos monoinsaturados nos pacientes com poucas les?es e intermedi?rias, quando comparado com pacientes sem les?o (p<0,05). A express?o do ECHDC3 foi 1,2 vezes mais alta em pacientes com poucas les?es que em pacientes sem les?o (p=0,023), e 1,8 vezes mais baixa em pacientes com les?o grave que em pacientes sem les?o (p=0,020). Na segunda casu?stica, a express?o do ECHDC3 foi 1,93 mais alta em pacientes com les?o intermedi?ria do que com poucas les?es (p = 0.011) e 1,91 vezes mais alta em pacientes com les?o grave que em poucas les?es (p = 0.013). A an?lise de Spearman mostrou uma correla??o entre os grupos de Friesinger com a express?o do ECHDC3 (r = 0.327, p =0.037) , e deste com o percentual de gordura visceral (r = 0.416, p =0.009). O ?ndice de Friesinger tamb?m mostrou uma correla??o com o consumo de carboidrato (r = 0.754, p = 0.002), vitamina B1 (r = 0.507, p = 0.001), vitamina B2 (r = 0.388, p = 0.012), folato (r = 0.599, p = 0.000) e magn?sio (r = 0.528, p = 0.003). Verificou-se que o aumento de ?cido ol?ico s?rico, da express?o do ECHDC3 e da gordura visceral podem contribuir para a progress?o da aterosclerose, uma vez que estes podem favorecer a ? ? oxida??o, rea??o que favorece a forma??o de esp?cies reativas de oxig?nio, desencadeando inflama??o, um dos principais gatilhos para a aterosclerose. Tamb?m foi visto que o consumo de carboidratos e alguns micronutrientes podem favorecer a progress?o da aterosclerose, j? que o aumento da ingest?o destes nutrientes pode propiciar a defici?ncia na absor??o ou estresse oxidativo, que implica diretamente na etiologia desta doen?a. / Coronary arterial disease is a at leading cause of death worldwide and can be triggered by alterations in the serum profile of fatty acids, by patterns of gene expression, changes in dietary intake, and alteration anthropometric. The early diagnosis of this pathophysiology is a challenge in translational medicine, since the methods used are expensive and / or invasive. The aim in the study was to identify biomarkers for the early diagnosis of atherosclerosis through the relationship of serum fatty acid profile, enoyl-coA hydratase (ECDHC3) mRNA expression and nutritional factors in patients without lesions and with different extensions of the atherosclerotic lesion. The study was observational, with the sample collected for convenience in two casuistry in the Hemodynamics sector of the Onofre Lopes University Hospital (HUOL). In the first series, 59 patients partipated (n1, 2011-2013) and in the second 41 individuals ( n2, 2014-2015), both aged 30-74 years and who were undergoing coronariography for the first time. The extent of atherosclerotic lesions was determined by Friesinger index, the biochemical profile by semi-automated spectrometry; the concentration of fatty acids by gas chromatography; gene expression of ECHDC3 mRNA by real-time PCR; food consumption and dietary intake for two 24-hour dietary intake recalls, anthropometric parameters and corporal composition by the electric bioimpedance, measuring tape and stadiometer scale.Patients were classified into groups: no lesion (n1 = 18 / n2 = 8), low lesions (n1 = 17 / n2 = 6), intermediate lesions (n1 = 17 / n2 = 15) and major lesion (n1= 7 / n2 = 12). In n1 was observed high serum concentrations of oleic acid and monounsaturated fatty acids in patients with low lesions and intermediate when compared to patients without lesions (p <0.05). ECHDC3 expression was 1.2 fold-higher in patients with low lesions than in patients without lesions (p = 0.023), and 1.8 fold- lower in patients with major lesions than in patients without lesions (p = 0.020). In the second casuistry, the expression of ECHDC3 was 1.93 fold-higher in patients with intermediate lesions than in low lesions (p = 0.011) and 1.91 fold-higher in patients with severe lesions than in low lesions (p = 0.013). Spearman's analysis showed a positive correlation showed a between ECHDC3 mRNA expression and Friesinger index (r = 0.327, p = 0.037), between the gene and visceral fat (r = 0.416, p = 0.009). The Friesinger index also showed a correlation with the consumption of carbohydrate (r = 0.754, p = 0.002), vitamin B1 (r = 0.507, p = 0.001), vitamin B2 (r = 0.388, p = 0.012), folate (r = 0.599, p = 0.000), magnesium (r = 0.528, p = 0.003). It was verified that oleic acid, ECHDC3 expression, percentage of visceral fat could favors ?-oxidation, trigger for inflammation and CVD; while the greater consumption of carbohydrate and some micronutrients, also could be associated with the CVD development, since the excess or decreased absorption can favors the oxidative stress, that favors the atherosclerosis.
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Mieliniza??o cerebral p?s-natal em modelo de autismo induzido por exposi??o pr?-natal ao ?cido valpr?ico / Postnatal brain myelination in an animal model of autism induced by prenatal exposure to valproic acidSousa, Carolina Ara?jo 31 August 2017 (has links)
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Previous issue date: 2017-08-31 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq) / A forma??o de circuitos neurais durante o desenvolvimento se d? atrav?s de uma complexa intera??o entre fatores gen?ticos e ambientais, que influenciam m?ltiplos eventos como a neurog?nese, a sinaptog?nese e a mieliniza??o. Em transtornos do desenvolvimento, como o transtorno do espectro autista (TEA), intercorr?ncias nesse processo levam ? m?-forma??o da circuitaria neural e, consequentemente, a d?ficits de intera??o social, interesses restritos e movimentos estereotipados, entre outros. Recentemente, realizamos em nosso laborat?rio a an?lise do transcriptoma do c?rtex frontal no modelo animal de autismo induzido por exposi??o a ?cido valpr?ico (VPA) in utero. Observamos que ratos com 15 dias de idade (P15) apresentam aumento da express?o de genes relacionados ? estabilidade sin?ptica e redu??o de genes relacionado ? mielina, sugerindo poss?veis mecanismos moleculares para as varia??es comportamentais previamente observadas nestes animais. Portanto, o objetivo desta disserta??o foi aprofundar este estudo investigando o padr?o de mieliniza??o no enc?falo de animais tratados com VPA em diferentes idades p?s-natais (infantil: P15 e adulta: P60). Para tanto, os grupos experimental e controle foram gerados, respectivamente, atrav?s da inje??o de VPA (500 mg/kg i.p.) ou salina em f?meas gr?vidas durante o dia embrion?rio 12.5 (E12.5). A an?lise da integridade da mielina foi realizada por duas abordagens: (1) an?lise da express?o de genes relacionados ? mielina (Mobp, Plp1, Mag e Klhl1), por PCR quantitativo, no c?rtex frontal de animais em P15; e (2) quantifica??o histol?gica da distribui??o de mielina em cinco sub-regi?es do c?rtex frontal e corpo caloso de animais P15 e P60. Dos quatro genes avaliados, observamos significativa diminui??o na express?o de Mobp e Mag em animais VPA em P15. A an?lise histol?gica de mielina mostrou redu??o significativa na intensidade de marca??o no c?rtex cingulado anterior em animais VPA em P60, por?m n?o detectou diferen?a na intensidade de marca??o em animais VPA em P15 quando comparados aos controles. Conclu?mos assim que animais VPA neonatos t?m reduzida express?o de genes relacionados a compacta??o da mielina, por?m sem altera??es no conte?do lip?dico da mielina nas ?reas analisadas. Animais adultos, por sua vez, apresentaram altera??es no conte?do lip?dico da mielina no c?rtex cingulado anterior. Em conjunto, estes resultados sugerem que dist?rbios na comunica??o entre circuitos frontais neste modelo de autismo podem ocorrer inicialmente devido altera??es na organiza??o da mielina, levando a redu??es de mielina no adulto. / The formation of brain circuits during neural development occurs through the interaction between timely regulated genetic and environmental signals, which influence multiple events such as neurogenesis, synaptogenesis, and myelination. In developmental disorders, such as autism spectrum disorders (ASD), deficits in these processes may lead to neural circuitry malformations and, in consequence, to social interaction deficits, restricted interests, and stereotyped movements, among others. Recently, we performed a transcriptome analysis of the frontal cortex of an animal model of autism induced by valproic acid (VPA) in utero in our lab. We observed that VPA animals at the postnatal age 15 (P15) show an increased expression of genes related to synaptic stability and a decrease in the expression of myelin-related genes, suggesting possible molecular mechanisms for the behavioral deficits previously observed in these animals. Therefore, the aim of this Master?s thesis was to further investigate the myelination pattern in the forebrain of VPA-treated rats at different postnatal ages (infant: P15 and adult: P60). For that, experimental and control groups were generated by injecting pregnant dams with 500 mg/Kg i.p. VPA or saline, respectively, on embryonic day 12.5 (E12.5). Analysis of myelin integrity was conducted by two different approaches: (1) gene expression analysis of myelin-related genes (Mobp, Plp1, Mag, and Klhl1) in dissected samples of the frontal cortex of P15 rats by quantitative real-time PCR; and (2) histological quantification of myelin distribution in five sub-regions of the frontal cortex and corpus callosum of P15 and P60 animals. Of all genes analyzed, we observed a significant decrease in Mobp and Mag expression in P15 VPA animals. Myelin analysis showed a significant reduction in myelin staining in the anterior cingulate cortex of VPA animals at P60, but no differences were observed at P15. In conclusion, infant VPA rats showed reduced expression of genes related to myelin assembly, without alterations in the lipid content of myelin in the areas analyzed. Adult animals, in contrast, showed a decrease in lipid content of myelin in the anterior cingulate cortex. Together, these results suggest that communication abnormalities in frontal circuits in this animal model of autism may occur initially due to alterations in myelin organization, leading to myelin reduction in adulthood.
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Potential of Blockchain and Cryptoeconomics in Developing Independent and Constructive Journalism : Case Study on Steem Blockchain and Steemit NetworkAlkhalaf, Khalaf January 2020 (has links)
Advanced Technology drives the increasing anti-censorship, decentralised social media networks, and publishing platforms that are based on blockchain, where no single party can control these platforms, which results in safeguarding information circulation, freedom to publish, and independence of journalism. Furthermore, cryptoeconomics associated with blockchain creates an easy economic model to find sustainable financing for independent journalism by Initial Coin Offering. Meanwhile, adopting a reward system by these publishing platforms has generated sustainable income sources for content creators, allowing them to be independent and motivated to create high-quality constructive content, which contributes to developing communities through disbursing knowledge in forms of constructive journalism. This study presents the potential of blockchain and cryptoeconomics in developing independent and constructive journalism, especially in developing countries. Through analysing the structure of Steem Blockchain, and empirical analysis of journalistic content on Steemit network in terms of the amount of payout that content creators and curators receive, based on the system of reward according to the content value that is determined by community member voting. Besides selected sample interviews with journalists, writers, and publishers in the Arab World which is undergoing turmoil and transition and needs constructive journalism, asking for their opinions about the potential that blockchain and cryptoeconomics have to support independent and constructive journalism. The results of the study demonstrated that journalistic posts classified under constructive journalism could achieve a high payout according to the reward system based on community voting for the content value. Meanwhile, journalists and writers have expected that this new economic model can enhance the financial independence of journalists and develop independent and constructive journalism in developing countries.
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A brain-computer interface for navigation in virtual realityAlchalabi, Bilal 04 1900 (has links)
L'interface cerveau-ordinateur (ICO) décode les signaux électriques du cerveau requise par l’électroencéphalographie et transforme ces signaux en commande pour contrôler un appareil ou un logiciel. Un nombre limité de tâches mentales ont été détectés et classifier par différents groupes de recherche. D’autres types de contrôle, par exemple l’exécution d'un mouvement du pied, réel ou imaginaire, peut modifier les ondes cérébrales du cortex moteur. Nous avons utilisé un ICO pour déterminer si nous pouvions faire une classification entre la navigation de type marche avant et arrière, en temps réel et en temps différé, en utilisant différentes méthodes. Dix personnes en bonne santé ont participé à l’expérience sur les ICO dans un tunnel virtuel. L’expérience fut a était divisé en deux séances (48 min chaque). Chaque séance comprenait 320 essais. On a demandé au sujets d’imaginer un déplacement avant ou arrière dans le tunnel virtuel de façon aléatoire d’après une commande écrite sur l'écran. Les essais ont été menés avec feedback. Trois électrodes ont été montées sur le scalp, vis-à-vis du cortex moteur. Durant la 1re séance, la classification des deux taches (navigation avant et arrière) a été réalisée par les méthodes de puissance de bande, de représentation temporel-fréquence, des modèles autorégressifs et des rapports d’asymétrie du rythme β avec classificateurs d’analyse discriminante linéaire et SVM. Les seuils ont été calculés en temps différé pour former des signaux de contrôle qui ont été utilisés en temps réel durant la 2e séance afin d’initier, par les ondes cérébrales de l'utilisateur, le déplacement du tunnel virtuel dans le sens demandé. Après 96 min d'entrainement, la méthode « online biofeedback » de la puissance de bande a atteint une précision de classification moyenne de 76 %, et la classification en temps différé avec les rapports d’asymétrie et puissance de bande, a atteint une précision de classification d’environ 80 %. / A Brain-Computer Interface (BCI) decodes the brain signals representing a desire to do something, and transforms those signals into a control command. However, only a limited number of mental tasks have been previously detected and classified. Performing a real or imaginary navigation movement can similarly change the brainwaves over the motor cortex. We used an ERS-BCI to see if we can classify between movements in forward and backward direction offline and then online using different methods. Ten healthy people participated in BCI experiments comprised two-sessions (48 min each) in a virtual environment tunnel. Each session consisted of 320 trials where subjects were asked to imagine themselves moving in the tunnel in a forward or backward motion after a randomly presented (forward versus backward) command on the screen. Three EEG electrodes were mounted bilaterally on the scalp over the motor cortex. Trials were conducted with feedback. In session 1, Band Power method, Time-frequency representation, Autoregressive models and asymmetry ratio were used in the β rhythm range with a Linear-Discriminant-analysis classifier and a Support Vector Machine classifier to discriminate between the two mental tasks. Thresholds for both tasks were computed offline and then used to form control signals that were used online in session 2 to trigger the virtual tunnel to move in the direction requested by the user's brain signals. After 96 min of training, the online band-power biofeedback training achieved an average classification precision of 76 %, whereas the offline classification with asymmetrical ratio and band-power achieved an average classification precision of 80%.
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A brain-computer interface for navigation in virtual realityAlchalabi, Bilal 04 1900 (has links)
L'interface cerveau-ordinateur (ICO) décode les signaux électriques du cerveau requise par l’électroencéphalographie et transforme ces signaux en commande pour contrôler un appareil ou un logiciel. Un nombre limité de tâches mentales ont été détectés et classifier par différents groupes de recherche. D’autres types de contrôle, par exemple l’exécution d'un mouvement du pied, réel ou imaginaire, peut modifier les ondes cérébrales du cortex moteur. Nous avons utilisé un ICO pour déterminer si nous pouvions faire une classification entre la navigation de type marche avant et arrière, en temps réel et en temps différé, en utilisant différentes méthodes. Dix personnes en bonne santé ont participé à l’expérience sur les ICO dans un tunnel virtuel. L’expérience fut a était divisé en deux séances (48 min chaque). Chaque séance comprenait 320 essais. On a demandé au sujets d’imaginer un déplacement avant ou arrière dans le tunnel virtuel de façon aléatoire d’après une commande écrite sur l'écran. Les essais ont été menés avec feedback. Trois électrodes ont été montées sur le scalp, vis-à-vis du cortex moteur. Durant la 1re séance, la classification des deux taches (navigation avant et arrière) a été réalisée par les méthodes de puissance de bande, de représentation temporel-fréquence, des modèles autorégressifs et des rapports d’asymétrie du rythme β avec classificateurs d’analyse discriminante linéaire et SVM. Les seuils ont été calculés en temps différé pour former des signaux de contrôle qui ont été utilisés en temps réel durant la 2e séance afin d’initier, par les ondes cérébrales de l'utilisateur, le déplacement du tunnel virtuel dans le sens demandé. Après 96 min d'entrainement, la méthode « online biofeedback » de la puissance de bande a atteint une précision de classification moyenne de 76 %, et la classification en temps différé avec les rapports d’asymétrie et puissance de bande, a atteint une précision de classification d’environ 80 %. / A Brain-Computer Interface (BCI) decodes the brain signals representing a desire to do something, and transforms those signals into a control command. However, only a limited number of mental tasks have been previously detected and classified. Performing a real or imaginary navigation movement can similarly change the brainwaves over the motor cortex. We used an ERS-BCI to see if we can classify between movements in forward and backward direction offline and then online using different methods. Ten healthy people participated in BCI experiments comprised two-sessions (48 min each) in a virtual environment tunnel. Each session consisted of 320 trials where subjects were asked to imagine themselves moving in the tunnel in a forward or backward motion after a randomly presented (forward versus backward) command on the screen. Three EEG electrodes were mounted bilaterally on the scalp over the motor cortex. Trials were conducted with feedback. In session 1, Band Power method, Time-frequency representation, Autoregressive models and asymmetry ratio were used in the β rhythm range with a Linear-Discriminant-analysis classifier and a Support Vector Machine classifier to discriminate between the two mental tasks. Thresholds for both tasks were computed offline and then used to form control signals that were used online in session 2 to trigger the virtual tunnel to move in the direction requested by the user's brain signals. After 96 min of training, the online band-power biofeedback training achieved an average classification precision of 76 %, whereas the offline classification with asymmetrical ratio and band-power achieved an average classification precision of 80%.
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A middle manager's response to strategic directives on integrated care in an NHS organisation : developing a different way of thinking about prejudiceYung, Fiona Yuet-Ching January 2013 (has links)
This thesis examines a middle manager’s response to strategic directives on integrated care in a National Health Service (NHS) organisation and the development of an awareness of prejudice that acknowledges its relationship to the process of understanding. The research focuses on an integration of two community NHS trusts and an NHS hospital trust into one integrated care organisation (ICO). A change programme was initiated and promulgated on an assumption that integrating the three organisations would facilitate integrated care. However, despite the use of organisational change approaches (such as communication plans and systematic approaches to staff engagement), implementing the strategy directives in practice remained problematic. What emerged during the integration process was resistance to change and a clear division in the different ways of working in the community NHS trusts versus the community and hospital trusts – differences that became apparent from the prejudices of individuals and staff groups. The proposition is that prejudice is an important aspect of relationships whose significance in processes of change is often overlooked. I argue that prejudice is a phenomenon that emerges in the processes of particularisation, which I describe as an ongoing exploration and negotiation in our day-to-day activities of relating to one another. Our pejorative understanding of the term ‘prejudice’ has overshadowed more subtle connotations, which I propose are unhelpful in understanding change in organisations. However, I suggest a different way of thinking about prejudice – namely as a process that should be acknowledged as a characteristic of human beings relating to one another, which has the potential to generate and enhance understanding. The research is a narrative-based inquiry and describes critical incidents during the integration process of the three organisations and focusing on interactions between key staff members within the organisation. In paying attention to our ongoing relationships, there has been a growing awareness of disconnection from traditional management practices, which advocate systematic approaches and staff engagement techniques that are designed to encourage cooperation and reduce resistance to proposed change. This thesis challenges assumptions surrounding prejudice and how middle managers traditionally manage organisational change in practice in their attempts to apply deterministic approaches (which assume a linear causality) to control and influence human behaviour. I have taken into consideration a hermeneutic perspective on prejudice, drawing on the work of Hans Georg Gadamer, and have argued from the viewpoint of the theory of complex responsive processes. This offers an alternative way of thinking about management as social processes that are emergent in our daily interactions with one another, that are not based on linear causality, or on locating leadership and management with individuals. It provides a way of taking seriously the relationships between individuals by paying attention to what emerges from the interplay of our expectations and intentions. This leads to a different way of thinking about the relationship between prejudice and strategic directives, which I argue are not fixed instructions but unpredictable articulations of our gestures and responses that emanate from social interaction and continually iterate our thinking over time. This paradoxically influences how we make generalisations and particularise them in reflecting on and revising our expectation of meaning I suggest that it is not possible to predetermine a strategic outcome; and that traditional management practice, which locates change with individuals – and reduces aspects of organisational life, such as resistance, into a problem to be fixed – obscures our capacity to understand the processes of organisational change in the context of a much wider social phenomenon. I therefore conclude that my original and significant contribution to the theory of complex responsive processes and to practice is encouraging a different way of thinking about prejudice – as a process that can be productive and generate understanding, when considered as encompassing our expectations of meaning, linked to our own self-interests. This then opens up possibilities for transforming ourselves in relation to others – and, through this process, to transform the organisations in which we work.
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A inteligência competitiva organizacional e os sistemas integrados de gestão ERP: um estudo nas indústrias calçadistas de JaúRodrigues, Rodrigo [UNESP] 31 July 2009 (has links) (PDF)
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rodrigues_r_me_mar.pdf: 689285 bytes, checksum: d38aa83282f6a5f21ac969d3baab7454 (MD5) / Universidade Estadual Paulista (UNESP) / No mundo globalizado as informações têm papel extremamente importante, visto que a internacionalização da economia exige excelência em relação aos sistemas de informação e documentação, por isso mesmo as informações se tornaram um recurso de gestão extremamente importante, mas nem sempre são valorizadas corretamente por parte das organizações. Nos ambientes organizacionais é absolutamente necessária a utilização de recursos tecnológicos para mediar o acesso e uso da informação pelo usuário, bem como para apoiar as distintas atividades organizacionais, desde as atividades cotidianas, o processo decisório, até o planejamento de ações estratégicas. O foco do problema de pesquisa refere-se aos fluxos informacionais em âmbito organizacional, mais especificamente os fluxos informacionais vinculados ao processo de inteligência competitiva organizacional (ICO). O objetivo deste estudo visava a analisar a contribuição das tecnologias de informação e comunicação (TICs), através dos sistemas integrados de gestão, mais especificamente o Enterprise Resource Planning (ERP), aplicado ao processo de inteligência competitiva organizacional nas indústrias associadas ao Sindicato Calçadista da cidade de Jaú/SP. Estudou-se os conceitos, definições, métodos e técnicas relacionados ao processo de ICO e às TICs, mais especificamente o ERP, por meio da análise da literatura nacional e internacional, assim como identificou-se e analisou-se no universo pesquisado as indústrias que possuem e aplicam o sistema ERP ou outro sistema semelhante, visando a analisar a relação do uso desse tipo de sistema para a competitividade organizacional. Da mesma forma, verificou-se a ocorrência do uso de métodos e técnicas aplicados ao processo de inteligência competitiva organizacional, desde que baseados em sistemas ERP. A pesquisa é descritiva exploratória... / In the world globalized the information have seen, extremely important role that to economy and requires excellence regarding the information and documentation systems, by that even the information became a resource of extremely important management, but do not always be valued correctly on the part of organizations. In organizational environments is absolutely necessary the utilization of technological resources for mediate the access and use of information by the user, as well like for support the distinct organizational activities, since the routine activities, the decision making process, until the planning of strategic actions. The focus of problem of research refers to the information flows in organizational scope, more specifically the information flows linked to the organizational competitive intelligence process (OCI). The objective of this study aims analyze the contribution of information and communication technologies (ICTs), through the management integrated systems, more specifically the Enterprise Resource Planning (ERP), applied to the organizational competitive intelligence process in the associated industries to the Footwear Syndicate of Jaú/SP city. Intends to study the concepts, definitions, approaches and techniques related to the OCI process and ICTs, more specifically the ERP, through the analysis the international and national literature, as well as intends identify and analyze in universe researched the industries that possess and apply the system ERP or another similar system, aiming at analyze the relation of the use of that system kind for the organizational competitiveness. Similarly, intends to verify the occurrence of use of approaches and techniques applied to the organizational competitive intelligence process, since based in ERP systems. The research is descriptive exploratory, of qualitative nature, analyzes data and information collected... (Complete abstract click electronic access below)
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Viabilidade t?cnica, qualidade nutricional e sensorial de produtos ? base de carne de Til?pia (Oreochromis niloticus) / Technical feasibility, nutritional and sensorial quality of products based on tilapia (Oreochromis niloticus) meatRESENDE, Alda Leticia da Silva Santos 08 June 2010 (has links)
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Previous issue date: 2010-06-08 / Once fish product offering by means of extractivism became stable, aquaculture emerges as a viable alternative to the increasing demand for quality protein. Brazilian low consumption of fish meat can be explained not only by cultural factors, but also by low offer of processed products as well as lack of practicity in meal preparation. In industry, after tilapia filleting, mechanically separated meat (MSM) is obtained which can be used for manufacturing of products with higher aggregated value. This work aimed at studying the technical feasibility, nutritional and sensorial qualities of tilapia fillet both in preserves and p?t? based on MSM, where protein and fatty acid profile alterations are observed. Simultaneously, a study on p?t? life span was carried out for a 180-days' period. Time x temperature binomial used (115?C x 20 minutes, and 115?C x 15 minutes, for the tilapia fillet and p?t?, respectively), were sufficent for assuring the commercial sterility of products. In relation to the preserved fillet, the most acceptable formula was of brine at 3%, and addition of fish seasoning to the covering oil, resulting in acceptance of 49%; 82%; 88%, and 65% for the attibutes: ?appearance?, ?taste?, ?texture? and for the purchasing intention, respectively. Both fatty acids EPA (Eicosapentaenoic) and DHA (docosaenoic) values were of 0.04% and 0.86%, respectively, while the sum of fatty acids series ?3 was equal to 0.34 g/100 g. Content of cholesterol was of 40.63 mg/100 g, considered low when compared to other products, such as eggs and meat. Physicalchemical composition of the product was: moisture: 76.21%; protein: 16.18%; ashes: 1.45%; ethereal extract: 3.71%. In relation to the p?t?, the storing period studied did not alter either the protein or the fatty acids profile, nor was the physical-chemical composition significantly alterated (moisture: 61.05%; protein: 9.44%; ashes: 2.41%; ethereal extract: 19.45%). By means of Quantitative Descriptive Analysis (QDA) a significant variation (P<0.05) was observed only on the averages attributed to ?spreadability? and ?creamy quality? throughout the study. Although ethereal extract in p?t? was high, cholesterol content was low (38.68 mg/100 g) taking into account that canoil oil was used in its formula, which not compromised quality of fatty acids profiled. DHA and linoleic acid values of p?t? were 0.35 and 5.60, respectively, and the sum of series ?3 fatty acids was of 1.58 g/100 g. After 180-day storing, acceptance frequency by consummers was of 95% for the ?global impression?; 91% for ?taste?; 89% for ?spreadability?, and 80% for ?appearance?. This study proves the technical, nutritional and market potential for products based on Tilapia meat. / Com a estabiliza??o da oferta de produtos de pesca pelo extrativismo, a aquicultura se mostra como alternativa vi?vel ao atendimento da demanda crescente por prote?na de qualidade. O baixo consumo brasileiro da carne de pescado pode ser explicado por fatores culturais, mas tamb?m pela baixa oferta de produtos processados e pela falta de praticidade no preparo da refei??o. Na ind?stria, ap?s o processo de filetagem da Til?pia, obt?m-se com aux?lio de m?quina despolpadeira, a carne mecanicamente separada (CMS) que pode ser utilizada na fabrica??o de produtos com maior valor agregado. Este trabalho teve como objetivo estudar a viabilidade t?cnica, qualidade nutricional e sensorial do fil? de Til?pia em conserva e do pat? ? base da CMS, observando as altera??es no perfil prot?ico e de ?cidos graxos. Foi realizado tamb?m estudo de vida ?til do pat? por per?odo de 180 dias. Os bin?mios tempo x temperatura utilizados (115?C x 20 minutos e 115?C x 15 minutos, para fil? e pat? de Til?pia, respectivamente), foram suficientes para garantir a esterilidade comercial dos produtos. Em rela??o ao fil? em conserva, a formula??o que obteve maior aceita??o foi a de salmoura a 3% e com tempero para peixe no ?leo de cobertura na qual a frequ?ncia de aceita??o do mesmo foi de 49%; 82%; 88% e 65% para os atributos ?apar?ncia?, ?sabor?, ?textura? e para a inten??o de compra, respectivamente. Os valores de ?cidos graxos EPA (eicosapentan?ico) e DHA (docosaexan?ico) foram de 0,04% e 0,86%, respectivamente e o somat?rio de ?cidos graxos da s?rie ?3 igual a 0,34 g/100 g. O teor de colesterol do produto foi de 40,63 mg/100 g sendo considerado baixo quando comparado ? outros alimentos como ovos e carnes. A composi??o f?sico-qu?mica do produto foi: umidade: 76,21%; prote?na: 16,18%; cinzas: 1,45%; extrato et?reo: 3,71%. Em rela??o ao pat?, o per?odo de armazenamento estudado n?o alterou o perfil prot?ico nem o de ?cidos graxos do produto, al?m de n?o ter alterado de forma significativa a sua composi??o f?sico-qu?mica (umidade: 61,05%; prote?na: 9,44%; cinzas: 2,41%; extrato et?reo: 19,45%). Atrav?s da An?lise Descritiva Quantitativa (ADQ) foi observada varia??o significativa (p<0,05) somente das m?dias dos atributos ?espalhabilidade? e ?cremosidade? ao longo do estudo. Apesar do teor de extrato et?reo do pat? ser elevado, o teor de colesterol foi reduzido (38,68 mg/100 g) visto que foi usado ?leo de canola na sua formula??o, o que tamb?m n?o comprometeu a qualidade do perfil de ?cidos graxos do mesmo. Os valores de DHA e ?cido linol?nico do pat? foram 0,35 e 5,60%, respectivamente e o somat?rio dos ?cidos graxos da s?rie ?3 foi de 1,58 g/100 g. Ap?s 180 dias de armazenamento, a frequ?ncia de aceita??o do pat? entre os consumidores foi de 95% para a ?impress?o global?; de 91% para o atributo ?sabor?; de 89% para a ?espalhabilidade? e de 80% para a ?apar?ncia?. Este estudo comprova o potencial t?cnico, nutricional e de mercado para os produtos ? base de carne de Til?pia.
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