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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
371

Avaliação do Desempenho do Teste de Rastreio “Memory Impairment Screen” para Demência na Doença de Alzheimer / Performance Evaluation of the "Memory Impairment Screen" Test for Dementia in Alzheimer's Disease

Petrillo, Sandra Lúcia 14 July 2017 (has links)
Submitted by SANDRA LUCIA PETRILLO (sandrapetrillo.longlife@gmail.com) on 2017-12-11T17:56:53Z No. of bitstreams: 1 Dissertação_Mestrado_Sandra_Petrillo.pdf: 5408729 bytes, checksum: 260301e7ac6761c455f3e28f08f23ac3 (MD5) / Submitted by SANDRA LUCIA PETRILLO (sandrapetrillo.longlife@gmail.com) on 2017-12-11T18:47:11Z No. of bitstreams: 1 Dissertação_Mestrado_Sandra_Petrillo.pdf: 5408729 bytes, checksum: 260301e7ac6761c455f3e28f08f23ac3 (MD5) / Approved for entry into archive by Luciana Pizzani null (luciana@btu.unesp.br) on 2017-12-12T16:04:58Z (GMT) No. of bitstreams: 1 petrillo_sl_me_bot.pdf: 5408729 bytes, checksum: 260301e7ac6761c455f3e28f08f23ac3 (MD5) / Made available in DSpace on 2017-12-12T16:04:58Z (GMT). No. of bitstreams: 1 petrillo_sl_me_bot.pdf: 5408729 bytes, checksum: 260301e7ac6761c455f3e28f08f23ac3 (MD5) Previous issue date: 2017-07-14 / Objetivo: Avaliar desempenho do teste de rastreio Memory Impairment Screen (MIS) para a triagem diagnóstica da Demência na Doença de Alzheimer (DDA). Casuística e método: Estudo de acurácia realizado no Ambulatório de Geriatria do Centro de Saúde Escola da Faculdade de Medicina de Botucatu – Unesp. Casuística de 126 pacientes idosos, sendo aplicado o teste de avaliação cognitiva MIS, utilizando-se como padrão ouro os critérios diagnósticos da DDA propostos por Frota. O valor diagnóstico foi analisado pelo cálculo da sensibilidade, especificidade, valores preditivos (positivo e negativo) e razão de verossimilhança positiva e negativa. A curva ROC foi traçada para contribuir na avaliação do desempenho do MIS no diagnóstico da DDA. Resultados: Foram avaliados 126 idosos com média de idade de 71,6 + 7,8 anos, maioria do sexo feminino (65,9%) e com 1 a 4 anos de estudo (40%). A presença do diagnóstico de Doença de Alzheimer foi observada em 18 (14,3%) dos idosos avaliados. O teste de rastreio cognitivo pelo MIS apresentou valor de sensibilidade de 72,2%, especificidade de 83,3%, valor preditivo positivo de 41,9% e negativo de 94,7% e razões de verossimilhanças positiva de 433 e negativa de 33,3. A área sob a curva ROC foi de 0,78 (IC 95%, 0,65-0,9). Conclusão: O presente estudo evidenciou a aplicabilidade do teste MIS e sua eficácia no diagnóstico das alterações cognitivas em pacientes idosos, com valores significativos de sensibilidade e especificidade; apresentou vantagens de rapidez, fácil aplicabilidade e interpretação; independente de cultura, linguagem e escolaridade. O MIS oferece vantagens importantes como teste de rastreio para uso em cuidados primários a saúde, sendo necessário estudos complementares que possam indicar o uso isolado deste teste para exclusão de demência. / Objective: To evaluate the performance of the Memory Impairment Screen (MIS) for the diagnostic screening of Dementia in Alzheimer's Disease (AD). Methods: Accuracy study performed at the Geriatrics Outpatient Clinic of the School Health Center of Botucatu Medical School - Unesp. A total of 126 elderly patients were enrolled, and the MIS cognitive evaluation test was applied, using the AD diagnostic criteria proposed by Frota as the gold standard. The diagnostic value was analyzed by the calculation of sensitivity, specificity, predictive values (positive and negative) and positive and negative likelihood ratio. The ROC curve was drawn to contribute to the evaluation of MIS performance in the diagnosis of AD. Results: A total of 126 elderly individuals with a mean age of 71.6 ± 7.8 years, most of them female (65.9%) and 1 to 4 years of education (40%) were evaluated. The presence of the diagnosis of Alzheimer's disease was observed in 18 (14.3%) of the elderly evaluated. The MIS cognitive screening test showed a sensitivity of 72.2%, specificity of 83.3%, positive predictive value of 41.9% and negative of 94.7% and likelihood ratio of 433 and negative of 33,3. The area under the ROC curve was 0,78 (95% CI, 0.65-0.9). Conclusion: The present study evidenced the applicability of the MIS test and its efficacy in the diagnosis of cognitive alterations in elderly patients, with significant values of sensitivity and specificity; Presented advantages of speed, easy applicability and interpretation; Independent of culture, language and schooling. MIS offers important advantages as a screening test for use in primary health care, and further studies are needed to indicate the use of this test alone to exclude dementia.
372

Le XIXe siècle dans le cinéma de Luchino Visconti : scènes et poétique du décor / The 19th century in the Luchino Visconti’s cinema : scenes and poetics in film sets

Guétin, Marie-Laure 26 November 2012 (has links)
Cette thèse se propose de mettre en relief des enjeux esthétiques et théoriques encore inaperçus du décor filmique, en prenant pour exemple le travail de Luchino Visconti, dont le cinéma fournit un cadre privilégié pour mener une telle recherche. Cinq grands films en costumes situés dans un XIXe siècle tardif, entre 1860 et 1911, constituent le corpus de l’étude, que vient compléter l’horizon réflexif des mises en scène de théâtre. On se donne pour tâche de relever et de faire ressortir les fonctions descriptive, historique et dramaturgique du décor. Le concept de scène ouvre ce décor XIXe à son extension la plus large : de l’espace au temps, du plus matériel au moins évidemment perceptible, du visuel au sonore. Le décor est cette scène, à la plasticité et la malléabilité remarquables, sur laquelle se met en place une poétique indissociable des perspectives temporelles. Comme scène, le décor est là où l’émergence du XIXe se noue, se joue et se structure selon trois niveaux : l’historicité, le drame, le temps. De la reconstitution historique à l’imagerie du siècle, des rhétoriques XIXe à la dramaturgie passionnelle, de la mise en scène du temps aux décors-temps en passant par les fictions et la corporéité du décor : voilà vers quelle poétique les scènes du décor acheminent le spectateur. Le distendant jusqu’à ses limites les plus élargies (le temps et ses mouvements, son anachronisme et sa fragmentation, ses fractures et sa musicalité), la réflexion aborde pour finir le décor XIXe comme cette forme cinématographique aspirant à une autre visibilité : telle une présence qui « inquiète le regard » (D. Païni). Cette approche du décor permet alors de repenser le travail de Visconti dans la modernité. / This doctoral thesis aims at highlighting aesthetic and theoretical aspects of film sets, throughout the work of Luchino Visconti. Five great costume films taking place in the late nineteenth century, between 1860 and 1911, complemented by the reflexive horizon of theatre stagings, constitute the corpus of the analysis. Descriptive, historical, and dramatic features of the film sets are identified and highlighted. The notion of scene enables us to consider the nineteenth century sets through a broad spatial and temporal scope; from the more substantial to the least clearly perceptible; from vision to audition. The film set is considered as a stage, with its characteristic plasticity and malleability, whereby the poetics is set up, indivisible from temporal perspectives. As a stage, the film set is the place where the emergence of the nineteenth century gets structured according to three levels: historicity, drama, and time. From the reconstruction of history to the imagery of the century, from the nineteenth century’s rhetoricity to the passionate drama, from the staging of time to temporal-settings, through film sets’ fictions and corporeality: this is the poetics towards which film sets’ scenes carry on the viewer. Distending the film set to its most extended limits (its time and movements, its anachronism and fragmentation, its fractures and musicality), towards the end, the reflection tackles the nineteenth century film sets as a cinematographic form aspiring to a new type of visibility — similar to a presence which "worries the sight" (D. Païni). This wide approach of the film set enables us to analyse Visconti’s work through the lens of modernity.
373

A Mixed Method Study of Teacher Perception of How Screen Time Affects Cognitive Development of Children between the Ages of Four and Five at One Early Childhood Education Center

Thomas, Angelique 21 May 2018 (has links)
The purpose of this study was to determine the impact screen time has on the cognitive development of children between the ages of four to five, at one early childcare education center. The significance of the study will help determine how the amount of screen time affects children’s cognitive development. The results of this study will help educational leaders determine how to effectively use technology for learning. Research suggests that the most important factor in a child’s development is a positive parent-child relationship, in which loving caregivers respond to a child’s cues and provide age-appropriate activities that nurture curiosity, exploration and learning (Lerner & Barr, 2014). This provides the foundation for teacher and child interactions in preschool programs. The role of early childhood educators lays the foundation for education. Currently, over 80% of children between the ages of three and five years are reported to be using some type of electronic device on a daily basis (Joan Ganz Cooney Center and Sesame Workshop, 2011). Time spent with these electronic devices is defined as screen time, the total amount of time spent in front of any and all screens (Common Sense Media, 2013). The National Association for the Education of Young Children (2012) defines technology and media tools as, “computers, tablets, multi-touch screens, interactive white boards, mobile devices, cameras, DVDs, music players, audio recorders, electronic toys, games, e-book readers, and older analog devices.” The impact of positive and consistent interactions to young children can help mold development. These meaningful interactions cannot be substituted with technology tools. The educators of School A are restricted to only allowing their students to engage in interactive screen time for a total of thirty minutes per week. This research was geared towards finding out if screen time effects a child’s cognitive development between the ages of four and five.
374

An Ecological Approach to Investigating the Influences of Obesity

January 2010 (has links)
abstract: "Globesity," as defined by the World Health Organization, describes obesity as a pandemic affecting at least 400 million people worldwide. The prevalence of obesity is higher among women than men; and in non-Hispanic black and Hispanic populations. Obesity has been significantly associated with increased all-cause mortality, and mortality from cardiovascular disease, obesity-related cancers, diabetes and kidney disease. Current strategies to curb obesity rates often use an ecological approach, suggesting three main factors: biological, behavioral, and environmental. This approach was used to develop four studies of obesity. The first study assessed dietary quality, using the Healthy Eating Index (HEI)-2005, among premenopausal Hispanic and non-Hispanic white women, and found that Hispanic women had lower total HEI-2005 scores, and lower scores for total vegetables, dark green and orange vegetables and legumes, and sodium. Markers of obesity were negatively correlated with total HEI-2005 scores. The second study examined the relationship between reported screen time and markers of obesity among premenopausal women and found that total screen time, TV, and computer use were positively associated with markers of obesity. Waist/height ratio, fat mass index, and leptin concentrations were significantly lower among those who reported the lowest screen time versus the moderate and high screen time categories. The third study examined the relationship between screen time and dietary intake and found no significant differences in absolute dietary intake by screen time category. The fourth study was designed to test a brief face-to-face healthy shopping intervention to determine whether food purchases of participants who received the intervention differed from those in the control group; and whether purchases differed by socioeconomic position. Participants in the intervention group purchased more servings of fruit when compared to the control group. High-income participants purchased more servings of dark green/deep yellow vegetables compared to those in the low-income group. Among those who received the intervention, low-income participants purchased foods of lower energy density, and middle-income participants purchased food of higher fat density. The findings of these studies support policy changes to address increasing access and availability of fruits and vegetables, and support guidelines to limit screen time among adults. / Dissertation/Thesis / Ph.D. Nursing and Healthcare Innovation 2010
375

Desenvolvimento de biossensor baseado em tirosinase para determinação de adenosina

Medeiros, Natália Goedtel January 2017 (has links)
Neste trabalho relata-se pela primeira vez a determinação de adenosina por um biossensor baseado em tirosinase. O biossensor foi desenvolvido mediante a modificação de um eletrodo de carbono impresso (SPE) com nanopartículas de ouro (AuNPs), tirosinase (Tyr) e Nafion, denominado biossensor Nafion/Tyr/AuNPs/SPE. As AuNPs sintetizadas possuem diâmetro médio de 15,0 ± 1,1 nm e sua função é melhorar a via de condução de elétrons entre a enzima e o eletrodo. Utilizou-se o aprisionamento com filme Nafion® para evitar a lixiviação enzimática da superfície do eletrodo. A tirosinase imobilizada apresentou boa atividade frente ao substrato catecol. Verificou-se que a adenosina atua como um inibidor do tipo não-competitivo. O biossensor é estável durante pelo menos 45 dias. Além disso, foi realizada a eletro-oxidação da adenosina para sua determinação. O biossensor apresenta sensibilidade superior em comparação com SPE, AuNPs/SPE e Nafion/AuNPs/SPE. As curvas de calibração revelaram duas faixas lineares para as concentrações de adenosina, de 1,0 × 10-5 mol L-1 até 5,0 × 10-5 mol L-1 e entre 6,0 × 10-5 mol L-1 e 1,2 × 10-4 mol L -1. O limite de detecção (3 × (desvio padrão + média dos brancos)/coeficiente angular da curva) foi de 7,0 × 10-7 mol L-1. / In this work we report for the first time the determination of adenosine by a biosensor based on tyrosinase. The biosensor was developed by modifying a screen-printed carbon electrode (SPE) with gold nanoparticles (AuNPs), tyrosinase (Tyr) and Nafion, denoted as Nafion/Tyr/AuNPs/SPE biosensor. The synthesized AuNPs have a mean diameter of 15.0 ± 1.1 nm and their function is to improve the electron conduction pathway between the enzyme and the electrode. The entrapment with Nafion® film was selected to prevent the enzyme lixiviation from the electrode surface. Immobilized tyrosinase showed good activity with the catechol substrate. It was found that adenosine acts as a non-competitive type inhibitor. The biosensor is stable for at least 45 days. In addition, the electro-oxidation of adenosine was performed for its determination. The biosensor has superior sensitivity compared to SPE, AuNPs/SPE and Nafion/AuNPs/SPE. Calibration curves revealed two linear ranges for adenosine concentrations of 1,010-5 mol L-1 up to 5,010-5 mol L-1 and from 6,010-5 mol L-1 to 1,210-4 mol L-1. The detection limit (3 × (standard deviation + mean of blanks)/slope of the curve) was 7,010-7 mol L-1.
376

Vers un dispositif de diagnostic point of care intégré : utilisation de la capillarité ainsi que des procédés de thermoformage et de sérigraphie. / Towards an integrated device for point-of-care diagnostics : use of capillarity with thermoforming and screen-printing processes.

Gosselin, David 06 October 2017 (has links)
Grâce aux technologies de la microfluidique (i.e. la manipulation d'un fluide dans un système ayant une dimension caractéristique sub-millimétrique), il est possible d'imaginer l'intégration de l'ensemble des fonctions ordinairement réalisées en laboratoire dans un système miniaturisé, réalisant ainsi un laboratoire sur puce. Cela peut ainsi permettre d'allier efficacité et bas-coût requis pour la réalisation de dispositif de diagnositcs médicaux utilisable en dehors d'infrastructure médicalisée, souvent appelés systèmes Point-of-Care. Pour la réalisation d'un tel dispositif, il semble important de concevoir l'intégration des différents composants du système d'une façon cohérente, et en prenant en compte l'ensemble des contraintes imposées par l'application finale ciblée. Le travail effectué au cours de cette thèse a ainsi été réalisé dans l'optique de proposer une réponse à cette problématique d'intégration dans le cadre du développement d'un système microfluidique de diagnostic Point-of-Care basé sur une réaction d'amplification d'ADN isotherme LAMP. Afin de pouvoir proposer un système bon marché et dont l'industrialisation est aisée, nous avons fait appel à l'utilisation du papier comme support et au thermoformage comme moyen de production. En effet à la fois l'industrie papetière et le procédé de thermoformage sont d'ores et déjà existant et proposent des fabrications en série. De plus, le faible coût du matériau et du procédé en question permettent d'envisager un dispositif final à bas-coût. Afin de pouvoir effectuer et détecter la réaction de LAMP la présence de fonctions actives telles qu'un chauffage et un outil de détection est nécessaire. Pour ces dernières, l'intégration a été réalisée par procédé sérigraphique. Le chauffage est effectué par effet Joule grâce au dépôt d'une couche d'encre conductrice à base de carbone. La détection est quant à elle faite par méthode potentiométrique, à l'aide d'électrode couverte de polyaniline. Il sera également montré que l'utilisation de ces méthodes de fabrication est pertinente en termes d'intégration car elles permettent une superposition des différentes fonctions actives, mais également leur intégration directement dans le système microfluidique. / Developments of microfluidics - the study of flows at the sub-millimetric dimensions - have made possible the integration of most of the macroscopic functions of laboratory fluidic systems in a miniaturized system, thus realizing a lab on a chip. This allows the conception of low cost, sensitive and efficient medical diagnostic device usable outside of a medical infrastructure. Such devices are called Point-of-Care (PoC) systems. The design and fabrication of such devices requires an elaborated and coherent integration that takes into account all the constraints imposed by the targeted final application.The work reported here, and performed during the PhD internship, is focused on the study of the concept and development of the integration of a PoC device based on the isothermal LAMP (Loop mediated AMPlification) reaction for the molecular analysis of DNA. In order to offer a cheap and easily industrialized system, we investigate the use of paper as the chip material and thermoforming as the mean to build the channels. These two techniques are currently used in the industry and their adaptation to the fabrication of such devices is easy and low-cost. In order to perform a LAMP reaction, specific functions such as a heating and a detection system are required. The integration of these functions was carried out using screen printing technology. Heating is done by Joule effect using a layer of carbon-based conductive ink. Detection is performed by a potentiometric method, using polyaniline-covered electrodes. It is shown that this approach is compatible with integration when the screen-printing layers are superposed. Besides they can be printed before thermoforming, resulting in a highly integrated system.
377

Development of shRNA screens to identify effectors of three complex traits : neighbour suppression of tumour growth and proliferation and protection from lipotoxicity in β-cells

Boquete Vilarino, Lorena January 2016 (has links)
RNA interference (RNAi) is a natural mechanism of cellular defence against exogenous double stranded RNA (dsRNA). The discovery of small dsRNA molecules which can be processed by the RNAi pathway in mammalian cells was one of the key advances in the study of functional genomics. These molecules can be designed to downregulate the expression of specific genes. Collections or libraries of dsRNA molecules targeting an extensive number of genes are now available. Using these libraries, numerous studies have implemented high-throughput screens for the study of molecular effectors of numerous phenotypes. The process of designing an RNAi screen requires the consideration of several critical factors during both the experimental and analysis phases. The experimental screen should aim to reproduce the biological phenomenon studied as closely as possible by choosing an adequate model and screening conditions. Phenotype evaluation and assessment of knockdown effects need careful consideration. The results obtained from large-scale RNAi screens are often complex. An analysis pipeline should be implemented which integrates the biological basis of the phenomenon and facilitates the interpretation of the data. This project designed and implemented an unbiased shRNA screen in two in vitro models relevant to carcinogenesis and diabetes. The first screen implemented used a model of neighbour suppression to study the molecular effectors of the response in tumorigenic cells to growth suppression cues from the surrounding tissue, a cellular interaction relevant in early tumorigenesis. The second screen studied two phenotypes relevant to diabetes: proliferation and resistance to lipotoxicity of β-cells in a reversibly immortalised  cell line. An integrative analysis pipeline was also developed to apply network biology and functional enrichment analysis methods for the interpretation of the data obtained from both screens.
378

Etude et optimisation de nouveaux types de capteurs pour la détection de polluants en milieu aquatique / Study and optimization of new types of sensors for the detection of pollutants in the aquatic environment

Lapeine, David 13 December 2016 (has links)
Dans cette thèse, nous présentons l’étude et la réalisation de micro-capteurs pour les systèmes de gestion des risques naturels. Le cahier des charges était centré sur les possibilités de concevoir des capteurs de polluants pour la surveillance des zones lagunaires dans le sud montpelliérain. Ces capteurs devaient être conçus dans une démarche « faible coût », résistant aux contraintes du milieu et pouvant communiquer et temps réel. Le premier chapitre s’appuie sur une étude bibliographique des différentes méthodes de mesures qui peuvent être utilisées pour faire de la détection de polluants et des matériaux potentiels pour réaliser le capteur. La technique de mesure la plus appropriée pour répondre aux deux premiers points du cahier des charges s’appuie sur la réalisation de transducteurs acoustiques à base de PZT en envisageant un processus technologique basé sur la technique de sérigraphie. Après avoir justifié notre choix de la technique de dépôt par sérigraphie, nous avons détaillé dans le second chapitre le processus technologique, en commençant par la réalisation de l’encre PZT, puis par le dessin des masques et pour finir nous avons détaillé les étapes de dépôt et de fonctionnalisation des transducteurs sur substrat d’alumine et sans substrat. A partir de ces premières réalisations, nous avons présenté les moyens et outils de caractérisation nécessaires pour pouvoir évaluer les différentes étapes du processus technologique mis en place, avec une attention particulière portée sur la qualité du matériau PZT et sur ses propriétés piézoélectriques. Il s’agit d’une part d’études morphologiques (images MEB, profilomètre) et structurelles (diffraction X, EDX) et d’autre part de la mesure des grandeurs piézoélectriques et diélectriques (piézomètre, analyses spectrales et d’impédances). Dans le troisième chapitre nous avons abordé le volet système de cette étude, avec la réalisation de prototypes basés sur les transducteurs sérigraphiés développés au chapitre 2. Les capteurs réalisés ont été testés et étalonnés avec des solutions d’éthanol et de toluène. Pour cela les capteurs sérigraphiés ont été testés sur des bancs expérimentaux afin de valider la technique de la mesure du temps de vol des ondes acoustiques. Dans l’optique de la miniaturisation et de l’intégration du système nous avons mis en place une électronique de commande embarquée à l’aide d’un module dédié. Enfin, pour pouvoir affiner les mesures, nous avons vu que nous pouvions envisager de croiser/corréler plusieurs paramètres. C’est ainsi que nous avons développé un capteur sérigraphié pour la mesure de la conductivité électrique en milieu aquatique. A partir des premiers résultats expérimentaux obtenus nous avons pu valider le principe de la méthode. Dans le quatrième et dernier chapitre de ce manuscrit, nous avons présenté les toutes premières études et réalisations sur la technologie LTCC. En reprenant les paramètres du processus utilisés lors des dépôts sur substrat d’alumine, nous avons réalisé et caractérisé des transducteurs déposés sur une feuille de céramique LTCC. Les premières caractérisations morphologiques et piézoélectriques sont encourageantes et les premiers tests acoustiques ont montré que la génération d’ondes acoustiques était tout à fait possible et qu’une utilisation en vue de la réalisation de capteurs de polluants était envisageable avec cette technologie. Enfin, nous avons pu réaliser une première structure 3D intégrant une cavité d’analyse. Là encore les débuts sont très prometteurs même s’il reste encore beaucoup de travail de « réglage » pour améliorer cette technologie. De plus, cette première réalisation 3D, ouvre de nombreuses perspectives au niveau de l’équipe en vue du développement de nouveaux capteurs. / In this thesis, we introduce the study and implementation of micro-sensors for natural risk management systems. The specification focused on the possibilities to develop a pollutant sensor capable of detecting the presence of hydrocarbons in the lagoon environments of southern Montpellier.These sensors should be designed in a "low cost" gait, resistant to environmental constraints and able to communicate in real time. The first chapter is based on a bibliographical study of the different methods of measurement that can be used for the detection of pollutants and potential materials for making the sensor. The most suitable measurement technology to answer the first two points of the specification is based on the implementation of acoustic transducers made from PZT with a technological process using the screen-printing technique. After justifying our choice of screen-printing deposition technique, we have detailed in the second chapter the technological process: first with the achievement of PZT ink, then with the masks design, and finally with the steps deposition and functionalization of transducers on alumina substrate and without substrate. From these first achievements, we have submitted the means and characterization tools needed to evaluate the different steps of the technological process set up with a focus on the quality of the PZT material and its piezoelectric properties. It is first about morphological (SEM images, profilometer) and structural (XRD, EDX) studies, and then about the measurement of piezoelectric and dielectric values (piezometer, spectral and impedance analyses). In the third chapter we discussed the sensor, with the production of prototypes based on screen-printed transducers developed in Chapter 2. The sensors were tested and calibrated with solutions of ethanol and toluene. For this, the screen-printed sensors were tested in experimental benches to validate the measurement technique of the acoustic waves time of flight. In view of the miniaturization and the integration of the system, we have set an electronic control board with a dedicated module. Finally in order to improve the measurements, we have shown that we could consider crossing/correlating several parameters. Thus, we have developed a screen-printed sensor for the measurement of the electrical conductivity in aquatic environment. From the first experimental results we validated the principle of the method. In the fourth and final chapter of this manuscript, we presented the first studies and achievements on the LTCC technology. By repeating the process parameters used during deposition on alumina substrate, we realized and characterized transducers placed on on a LTCC ceramic sheet. The first morphological and piezoelectric characterizations are encouraging, and the first acoustic tests have shown that the generations of acoustic waves, and a use for the production of sensors of pollutants were possible with this technology. Finally we have been able to achieve a first 3D structure incorporating an analysis cavity. Here again, results are very encouraging, although "adjustments" are needed to improve the technology. Also this 3D realization opens up many opportunities for the team to develop new sensors.
379

Design de superfície : um estudo sobre a aplicação do termocromismo em camisetas

Pippi, Luis Fernando Aita January 2010 (has links)
O estudo busca esclarecer pontos essenciais sobre o emprego da termocromia em têxteis por meio de sua aplicação em estampas em camisetas, respondendo questões sobre o poder expressivo destas e do uso da termocromia como recurso de qualificação em projetos de Design de Superfície. A pesquisa traz dados históricos da camiseta como objeto de design e moda. Nesse contexto verificou-se a relevância dos esclarecimentos técnicos sobre o funcionamento da tinta termocrômica, assim como apresenta-se no estudo uma gama de produtos que se utilizaram da aplicação desta técnica, além de estudos acadêmicos considerados inovadores nessa área de conhecimento. O objetivo principal do estudo é explorar novos conhecimentos sobre os sistemas e técnicas em relação à aplicabilidade da termocromia em estampas de camisetas, bem como mostrar as capacidades subjetivas de comunicação/expressão e de interatividade em produtos com essa tecnologia, que podem servir como auxílio para os designers em projetos inovadores. Neste sentido, foram propostos estudos experimentais de aplicação de estampas com tinta termocrômica em camisetas, que deram o sentido fundamental a esta dissertação, acrescentando conhecimento e abrindo espaço para novas pesquisas no âmbito interdisciplinar. Neste estudo de caso exploratório, foi possível concluir, que os métodos mostrados aqui são fatores importantes de inovação para o setor têxtil e de moda e que os testes produzidos provaram a necessidade de rigor técnico contido nas especificações técnicas do fornecedor. / This study aims to clarify some fundamental questions related to textile thermochromism in the application of t-shirt printing, namely the expressive power of prints and the use of thermochromism as a resource in surface design. The investigation brings historical data regarding the t-shirt as an object of design and fashion. In this context, the importance of technical clarification related to the performance of thermochromic ink is verified and a range of products utilized in this technique are presented. A number of innovative academic studies in this area are also presented. The main objectives of this study are to investigate new knowledge about the applicability of systems and techniques utilized in thermochromic t-shirt graphics and to demonstrate the subjective capacity of expression and interaction of products that utilize this technology, which can serve as an aid to designers in innovative projects. From this perspective, experimental tests in the application of thermochromic t-shirt printing were proposed, providing significance to this thesis, enhancing the knowledge in this field and promoting further interdisciplinary research. In this exploratory case study it was possible to conclude that the methods shown here represent important innovations in the textile and fashion sectors and that the tests demonstrated the necessity of technical rigor regarding manufacturers’ technical specifications.
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WETTING CHARACTERISTICS OF HERRIN COAL AND ITS APPLICATION FOR IMPROVED DUST CONTROL

Relangi, Durga Devika 01 May 2012 (has links)
This thesis has developed wetting characteristics of coal dust from Herrin coal seam in Illinois for improved respirable coal and quartz dust (< 10µm) control. Wetting characteristics were assessed by a wettability technique called Fixed Time Wettability (FTW) method which simulates the actual underground wetting environment. Immediate roof and immediate floor materials bulk samples were found to be 100% wettable by water alone, whereas coal seam samples were 55-90% wettable. Two variables: contact time between water droplets and dust particles and, the temperature of the water were found to affect the degree of wettability. FTW was carried out at as a function of water temperature (7.2oC to 40.5oC) and contact time (10 to 25 seconds) which increased wettability 2-18% and 8-32%, respectively. In addition, the wetted and un-wetted samples collected from wettability experiments were subjected to Scanning Electron Microscopy (SEM) and particle size distribution analyses. It was found that particles are irregular in shape in both wetted and un-wetted fractions and some agglomeration of fine particles was observed in a few un-wetted fraction samples. The concept of increased contact time was incorporated in engineering controls by increasing the wet scrubber filter screen inclination (which is a function of the screen surface area). The filter screen inclination was minimizing the pressure drop across it using Computational Fluid Dynamics (CFD) analysis. It was found that 60 degree (with respect to the vertical) would provide minimal pressure drop and should be considered for implementation. Additional research should be conducted on assessing selective wetting of different particle sizes of coal and quartz in airborne dust, developing data on wettability as a function of particle size and implementing the developed concepts such as contact time and temperature in the field for improved dust control.

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