Orientador: Adriana Vitorino Rossi / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Quimica / Made available in DSpace on 2018-08-04T19:15:03Z (GMT). No. of bitstreams: 1 Terci_DanielaBrottoLopes_D.pdf: 9748228 bytes, checksum: 095885c9317fc4d1076392518f606434 (MD5) Previous issue date: 2004 / Doutorado / Quimica Analitica / Doutor em Quimica

Orientadores: Marcelo Knobel, Daniela Zanchet / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Fisica Gleb Wataghin / Made available in DSpace on 2018-08-08T20:01:50Z (GMT). No. of bitstreams: 1 Alves_TatianaMidoriMartinsTelles_M.pdf: 13757564 bytes, checksum: 9fff2bc36efd863f581707b11f77fa22 (MD5) Previous issue date: 2007 / Resumo: Neste trabalho são realizados estudos de propriedades morfológicas, estruturais e magnéticas de nanopartículas de óxidos de ferro sintetizadas por métodos químicos. Procuramos relacionar os parâmetros de síntese às características das partículas produzidas com a finalidade de melhorar sua qualidade em relação às amostras comerciais e avaliar sua aplicabilidade em biomedicina. Foram adotados os métodos de síntese por co-precipitação de sais em solução aquosa e de decomposição térmica de dois diferentes precursores organometálicos: acetilacetonato de ferro III (Fe(acac)3) e ferro pentacarbonil (Fe(CO). Para caracterização desses sistemas, foram utilizadas as técnicas de microscopia eletrônica de transmissão convencional e de alta resolução, microscopia eletrônica de varredura com canhão de emissão de campo, difração de raios-X e medidas de magnetização, além de experimentos de transfecção em células HeLa e posterior detecção por imagens de ressonância magnética. Os estudos mostraram que as partículas sintetizadas por co-precipitação não apresentam muitas vantagens em relação às amostras comerciais, pois possuem larga distribuição de tamanhos. Através da síntese por decomposição térmica de Fe(acac)3, partículas com distribuição mais estreita foram produzidas e resultados positivos de incorporação por células HeLa e detecção por imagens de ressonância magnética foram obtidos. Com as partículas geradas pela decomposição térmica de Fe(CO)5 foram realizados tratamentos térmicos em atmosfera ambiente que proporcionaram aumento do grau de cristalização, aumento do diâmetro médio e estabilização de suas propriedades magnéticas, em detrimento da perda dos contornos esféricos e aumento na dispersão de tamanhos. De uma maneira geral, foi possível demonstrar que a decomposição térmica de compostos organometálicos em solventes orgânicos produz partículas mais homogêneas em relação àquelas produzidas por co-precipitação e às comercialmente disponíveis, e essa qualidade apresenta um grande potencial para aplicações biomédicas mais sofisticadas / Abstract: In this work, morphological, structural and magnetic investigations were performed in iron oxide nanoparticles synthesized by chemical methods. Our goal was to correlate the synthesis parameters to the characteristics of the produced particles to improve their quality when compared to commercial samples and to evaluate their applicability in biomedicine. The synthetic methods were the co-precipitation of metal salts in aqueous solution and the thermal decomposition of two different organometallic precursors: iron (III) acetylacetonate (Fe(acac)3) and iron pentacarbonil (Fe(CO)5). The following techniques were used for the characterization of these systems: transmission electron microscopy, high resolution transmission electron microscopy, field emission gun scanning electron microscopy, X-ray diffraction and magnetic measurements, in addition to incorporation experiments by HeLa cells and their detection by magnetic resonance imaging. The studies showed that nanoparticles synthesized by the co-precipitation method present no advantage over the commercial samples, once they have the same broad size distribution. Through thermal decomposition of Fe(acac)3, particles with narrower size distribution were produced and positive results on their incorporation by HeLa cells and magnetic resonance imaging detection were obtained. Thermal treatments under air atmosphere were performed in the particles generated by thermal decomposition of Fe(CO)5, giving rise to crystallization, an increase of the mean diameter and stabilization of their magnetic properties, with the disadvantages of loss of the spherical shape and increase of the size dispersion. In summary, it was possible to demonstrate that thermal decomposition of organometallic compounds in hot organic solvents produces more homogeneous particles when compared with those produced by co-precipitation and commercially available ones, and this quality presents great potential for more sophisticated biomedical applications / Mestrado / Física da Matéria Condensada / Mestre em Física

M.A. / This dissertation comprises an in-depth investigation into the domain of computer vision, with specific reference to the textile industry. The study consists of three main sections. In the first section, the computer-vision process is scrutinised in its entirety. Attention is given in this regard to what computer vision is, where it originated from, how it compares with human vision and what the motivations are for its implementation. Following, the computer-vision process is divided into four main components, namely image acquisition, image processing, image analysis and image interpretation. Subsequently, each component is discussed in greater detail, as well as aspects such as the hardware used in the course of the process, the algorithms that are implemented and the specific applications used for the process of analysis. In the second section, the focus is shifted to the textile industry, where our main focus lies. In this regard, examples are examined of the successful implementation of computer-vision technologies in the textile industry. In the third section, an investigation is launched into the specific problem for which a solution needs to be found in the present study, namely to determine whether computer vision constitutes a cost-effective way in which to locate broken thread during the spinning process. A wide range of algorithms has been applied for this purpose, whereafter the results of these experiments are announced.

Cette thèse traite des dégradations induites par la pompe (photo-noircissement) et les radiations ionisantes externes (radio-noircissement) dans les fibres optiques en silice dopées ytterbium (FDY) utilisées en environnement sévère. Au travers de caractérisations expérimentales et de modélisations inédites, elle analyse leur interaction et en tire les conséquences quant à la tenue des FDY aux radiations sous pompe. La première partie porte sur l’identification des défauts induits (centres colorés) et leurs mécanismes de formation/guérison. Elle s’appuie sur un ensemble de caractérisations post-irradiation (RPE, ARI, TL) réalisées sur des échantillons de préformes et sur leur corrélation originale (guérison thermique, couplage TL et ARI). L’étude systématique en fonction de la composition met en évidence l’influence des co-dopants (Al, Ce) sur la capture des charges libérées lors des processus d’ionisation. La seconde partie analyse le noircissement se développant sous l’effet simultané de la pompe et de l’irradiation ionisante. A partir d’un banc de mesures autorisant le suivi de la dégradation en temps réel, on montre que photo- et radio-noircissements résultent des mêmes centres colorés blanchis par la pompe. Ce résultat, ajouté aux mécanismes préalablement identifiés, permet de proposer un modèle physique local de la dégradation photo-radio-induite. La confrontation des simulations issues de ce modèle à une large variété d’observations originales faites « en ligne » conduit à sa validation. Il est ainsi démontré que, pour des débits de dose inférieurs à une valeur critique, la dégradation des FDY pompées et irradiées ne peut excéder leur niveau de photo-noircissement. / This thesis deals with the degradation induced by the pump (photodarkening, PN) and ionizing radiations (radiodarkening, RN) in ytterbium-doped optical fiber (YDF) used in harsh environments. Through original experimental characterizations and modeling, it analyses the interplay between PN and RN and reveals important and novel properties of the radiation resistance of pumped YDF. The first part investigates induced defects (color centers) together with their creation/recovery mechanisms. It used a set of post-irradiation characterizations (ESR, RIA, TSL) conducted on preform samples and benefited from their original correlation (thermal recovery protocols coupling TSL and RIA). A systematic study as a function of composition reveals the influence of co-dopants (Al, Ce) on the trapping of carrier freed during ionization processes. The second part examines the darkening build-up under the simultaneous action of the pump and an ionizing irradiation. By using a measurement bench that allowed us to follow the real-time “on line” degradation of fiber samples, we showed that photo- and radio-darkening both arise from the same color centers that can be bleached by the pump. On the basis of this finding and of the preceding identified mechanisms, we propose a local physical model of the photo-radio-induced darkening. The latter is thoroughly validated by further successful comparisons of simulated degradation with a wide variety of “on line” original observations. Then, we notably demonstrate that for dose rates lying below a critical value (explicited by our theory), the degradation of pumped and irradiated YDF never exceeds the photo-darkening level.

Rich Internet Applications (RIAs) are a new generation of web applications that break away from the concepts on which traditional web applications are based. RIAs are more interactive and responsive than traditional web applications since RIAs allow client-side scripting (such as JavaScript) and asynchronous communication with the server (using AJAX). Although these are improvements in terms of user-friendliness, there is a big impact on our ability to automatically explore (crawl) these applications. Traditional crawling algorithms are not sufficient for crawling RIAs. We should be able to crawl RIAs in order to be able to search their content and build their models for various purposes such as reverse-engineering, detecting security vulnerabilities, assessing usability, and applying model-based testing techniques. One important problem is designing efficient crawling strategies for RIAs. It seems possible to design crawling strategies more efficient than the standard crawling strategies, the Breadth-First and the Depth-First. In this thesis, we explore the possibilities of designing efficient crawling strategies. We use a general approach that we called Model-based Crawling and present two crawling strategies that are designed using this approach. We show by experimental results that model-based crawling strategies are more efficient than the standard strategies.

The thesis deals with concept of mobile application from a phase of a thought to the final concept of the application. The main goal of this thesis is a concept of mobile application for travellers, which will provide offline, but current information in their mobile phones during their travels. The first part contains introduction about mobile phones and platforms which they use, the next part deals with selected parts of UI and UX on Apple mobile phones and these findings are applied to the concept of mobile application. The whole concept is also influenced by findings from an online user survey and from analysis of applications of competitors. In this thesis is also described the evolution of the concept based on user testing. There are economic aspects of the aplication like monetizing the application and propagation described as well.

This thesis covers topic of mobile application development for Android and iOS. It also points out differences between Android and iOS programming. The main goal is to de-scribe the whole process of development which starts by choosing suitable mobile plat-forms and ends by distribution of finished application. The theory is shown on video streaming application. The first part of this thesis covers choosing of suitable platforms for development. Next chapter focuses on different development methods of mobile applica-tions. The rest of thesis is dedicated to Android and iOS development. There is one chapter covering software development kit and one chapter covering mobile user interface - its principles and creation methods. The last theoretical chapter covers fundamentals of each Android and iOS application. The whole development process of sample application is described in the seventh chapter. It includes functional and non-functional application re-quirements, analysis, design of user interface, implementation, testing and distribution of finished application. This thesis is supposed to be jump start for all new developers, who consider mobile application development.

This quantitative study investigated relationships among and between university early and late admitted freshmen and academic performance and persistence. The participants in this study consisted of 3,197 early freshmen applicants and 309 late freshmen applicants admitted at a large southwestern student centered public research university over the course of the year prior to the fall 2008 academic year. Significant results, using a statistical significance level of p < .05, were reported for the majority of variables examined: chi-square analysis revealed a significant relationship between application date and ethnicity; independent-samples t-tests revealed significant differences in SAT scores; 78.06% of late applicants were male compared to 40.83% of early applicants; mean GPA of early applicants was 2.62 compared to 2.18 among those who applied late; and lastly, 76.62% of early applicants returned the following year in comparison to 57.42% of late applicants. The results of this study provide preliminary support for the examination of admission policies and procedures in relation to late application. Recommendations are made for advising, counseling, and other interventions that may ease the transition of freshmen late applicants while enhancing retention and persistence.

Les propriétés des nanozéolithes, à savoir leur grande surface, leur stabilité hydrothermale et leur nature non toxique, permettent leur utilisation dans des applications prospectives, notamment la biomédecine (capteurs, administration de médicaments et de gaz) et la microbiologie (agents antibactériens). De nombreuses recherches ont été consacrées à l’étude de nouvelles applications biomédicales utilisant des matériaux zéolithiques, toutefois leur plein potentiel n’a toujours pas été pleinement dévoilé.Il est bien connu que la résistance croissante aux traitements établis de tumeurs et d’infections bactériennes par radiothérapie et antibiotiques est un problème de première importance. Par conséquent, le développement de nouvelles stratégies thérapeutiques pour résoudre ces problèmes est très démandé.L'objectif de cette recherche de doctorat est de synthétiser et de modifier post-synthétiquement des zéolithes nanométriques pour des applications biomédicales. Cela implique l'échange d'ions de zéolithe avec divers cations pour trouver celui qui convient le mieux aux applications souhaitées : le traitement antimicrobien, la réoxygénation des tissus tumoraux et l’administration de gaz.Dans cette étude, nous rapportons: (i) l'effet de la zéolithe FAU de type nanométrique modifiée au cuivre sur les bactéries de type ESKAPE (chapitre 3), (ii) l’utilisation de nanozéolithes contenant du métal comme outil d'oxygénation et de visualisation tissulaire (chapitre 4) et enfin (iii) l'utilisation de nanozéolithes FAU comme vecteur de l'oxyde nitrique et du dioxyde de carbone pour prévenir des maladies potentiellement létales (chapitre 5). / The properties of nanozeolites, namely, large surface area, hydrothermal stability and non-toxic nature, enable their utilization in forward-looking applications, including biomedicine (sensors, drug and gas delivery) and microbiology (antibacterial agents). Hence, a lot of research has been devoted to study the new biomedical applications using zeolitic materials, their full potential has still not been fully unveiled.It is well recognised that growing resistance to already established treatments of tumors and bacterial infections using radiotherapy and antibiotics is a distressing matter. Therefore, the development of new therapeutic strategies towards above issues is of great demand.The goal of this PhD research is to synthesise and post-synthetically modify nanosized zeolites for biomedical applications. This involves the ion-exchange of zeolite with various cations to find the most suitable one for desired applications in regards to antimicrobial treatment, tumour tissue reoxygenation and gas delivery.In this study, we report: (i) the effect of copper modified nanosized FAU type zeolite on ESKAPE type bacteria (Chapter 3), (ii) the metal containing nanozeolite as a tool for tissue oxygenation and visualisation using MRI (Chapter 4), and lastly (iii) the use of FAU nanozeolite as nitric oxide and carbon dioxide gas vector to prevent life threatening conditions (Chapter 5).

<p>Digital image processing techniques have many significant applications in industry. In this thesis, we focus on three problems in digital image processing. These three problems involve halftone images, information encoding and decoding, image alignment, and deep learning.</p><p>Specifically, the first problem is based on data-bearing halftone images, which are an aesthetically pleasing alternative to barcodes. We address the issues generated in the camera captured image alignment process. We perform some theoretical analysis and validate it by simulation. We also provide an optimal solution to the problem.</p><p>The second problem is about the alignment technique on a 3D surface. We develop a pipeline of surfaces coding to solve the alignment issues on 3D surfaces, which includes oblique surfaces and cylindrical surfaces.</p><p>The third problem is related to image retrieval. We propose a deep learning based solution to the fashion image retrieval task. Fashion image retrieval is significant to improve the customers’ experience in online shopping. A fast, accurate shopping item information retrieval system based on the customers’ uploaded image has been built by us. A novel solution is provided, and it achieves state-of-art accuracy in shopping items’ information retrieval.</p>