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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.
81

Faceamento de solo grampeado com malhas de aço : estudo dos critérios de dimensionamento / Soil nail facing with steel meshes : design parameters study

Rosa, Bruno Denardin da January 2015 (has links)
O uso de sistemas de faceamento flexíveis com malhas metálicas é uma alternativa viável ao uso do concreto projetado como faceamento em sistemas de solo grampeado. Vários modelos de malhas são empregados hoje para este uso, sendo classificados pela resistência à tração no sentido longitudinal. Mesmo que relevante, segundo Cala et al., (2012), somente este dado é insuficiente para o correto dimensionamento destas soluções. A presente pesquisa busca identificar quais os parâmetros de resistência são necessários para o dimensionamento de um faceamento em malha metálica. Para tanto foram avaliadas duas metodologias desenvolvidas especificamente para as malhas aplicadas junto com a solução de solo grampeado, os métodos Ruvolum e Macro1. Foram então desenvolvidos equipamentos, similares aos utilizados por Roduner (2011) e Cala et al. (2012), para caracterizar 4 diferentes modelos de malhas, avaliando a resistência das mesmas frente aos esforços considerados nos modelos de cálculo investigados, tração e o cisalhamento no contato malha/grampo. Deste modo, foram utilizados resultados de ensaios em escala real com a simulação de um talude em solo tratado com as 4 malhas, para a validação dos métodos de dimensionamento, e para investigar quais os parâmetros de resistência da malha são mais importantes. Como resultado foram determinadas as resistências das malhas avaliadas, sendo a de tração no sentido longitudinal entre 50 e 140 kN, e a resistência no contato malha/grampo, que variou entre 10 e 30 kN. Por fim foi realizada uma análise paramétrica com o método Ruvolum a fim de verificar a influência na variação da coesão, espessura instável e ângulo de atrito, dados nem sempre bem definidos em projeto. Os resultados mostram, como era esperado, a grande sensibilidade da variação nos resultados frente aos efeitos da coesão, sendo então recomendado, como em qualquer análise de estabilidade cautela no uso deste parâmetro. A análise destes resultados permite concluir que o método mais adequado para modelar um talude em solo grampeado com face em tela foi o Ruvolum, com previsões que se aproximaram das medições reais dos ensaios de campo. / The use of flexible facing systems with steel meshes is a viable alternative to the use of shotcrete as facing in soil nailing systems. Currently several different models meshes are being used today for this purpose, being classified only by the tensile strength in the longitudinal direction of the mesh. Even though this parameter is quite relevant, alone it cannot be used to design the flexible facing systems. So this research aims to identify which steel mesh strength parameters are really needed for the correct dimensioning of such solutions. In order to do so two calculation methodologies, specially developed for steel meshes design, were investigated. The design models are called Ruvolum and Macro1 Equipments were developed, similar to those presented in Cala et al. (2012), to investigate four different models of mesh, in order to find the strength parameters presented on the studied calculation models, being than tensile and shear. Thus, to validate the investigated design methodologies, field tests results were compared to the models predictions. As product of the research it was possible to determine the tensile strength of the 4 meshes models, being then ranging from 50 and 140 kN. Also it was possible to define the shear resistance in the nail head/mesh contact, which ranges from 10 to 30 kN. The last step of the research was a parametric analysis, performed with the Ruvolum method to evaluate the influence on the variation of cohesion, unstable thickness and friction angle in the predictions, since this data aren’t always available in ordinary projects. These analysis have showed that the most influent parameter is cohesion, one that is very hard to determine. Also it was found by the results analysis that the appropriate calculation model to simulate a slope stabilized with soil nail and steel meshes facing is the Ruvolum, due the closeness of the predictions to the real field data.
82

Construção de telas holográficas e aplicações / Construction of holographic screens and their applications

Magalhães, Daniel Souza Ferreira 14 August 2018 (has links)
Orientador: Jose Joaquín Lunazzi / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Fisica Gleb Wataghin / Made available in DSpace on 2018-08-14T06:28:04Z (GMT). No. of bitstreams: 1 Magalhaes_DanielSouzaFerreira_D.pdf: 18841445 bytes, checksum: 83953f45dd82288807d2ece70a0d3c17 (MD5) Previous issue date: 2009 / Resumo: A Tela holográfica é um elemento óptico difrativo gerado pela interferência de dois feixes de maneira a redistribuir convenientemente para um observador a luz que recebe com o objetivo de visualização de imagens sem óculos e com paralaxe. Neste trabalho descrevemos alguns métodos de obtenção de telas holográficas para aplicações em projeções com luz branca. As fundamentamos, analisamos os resultados obtidos, assim como descrevemos suas aplicações. / Abstract: Holographic screen is a difractive optical element generated by the interference of two beams in order to properly distribute to an observer the light it receives with the purpose of viewing parallax images without glasses. This work describes some methods for obtaining holographic screens looking forward applications with white light. We substantiate, analyze the results and describe their applications. / Doutorado / Ótica / Doutor em Ciências
83

Structural and functional characterization of human DDX5 and its interaction with NS5B of hepatitis C virus

Choi, Yook-Wah January 2011 (has links)
Philosophiae Doctor - PhD / Hepatitis C was first recognized as a transfusion-associated liver disease not caused by hepatitis A or hepatitis B virus after serological tests were developed to screen for their presence in the blood. The infectious agent was finally identified with the cloning of the cDNA of hepatitis C virus (HCV) using random polymerase chain reaction (PCR) screening of nucleic acids extracted from plasma of a large pool of chimpanzee infected with non-A non-B hepatitis. NS5B, a membrane-associated RNA-dependent RNA polymerase essential in the replication of HCV, initiates the synthesis of a complementary negative-strand RNA from the genomic positive-strand RNA so that more positive-strand HCV RNA can then be generated from the newly synthesised negative-strand template. The crystal structure of NS5B presented typical fingers, palm and thumb sub-domains encircling the GDD active site, which is also seen in other RNA-dependent RNA polymerases, and is similar to the structure of reverse transcriptase of HIV-1 and murine Moloney leukaemia virus. The last 21 amino acids in the C-terminus of NS5B anchor the protein to the endoplasmic reticulum (ER)-derived membranous web. NS5B has been shown to interact with the core, NS3/NS4A, NS4B and NS5A proteins, either directly or indirectly. Numerous interactions with cellular proteins have also been reported. These proteins are mainly associated with genome replication, vesicular transport, protein kinase C-related kinase 2, P68 (DDX5), α-actinin, nucleolin, human eukaryotic initiation factor 4AII, and human VAMP-associated protein. Previous studies have confirmed that NS5B binds to full-length DDX5. By constructing deletion mutants of DDX5, we proceeded to characterize this interaction between DDX5 and HCV NS5B. We report here the identification of two exclusive HCV NS5B binding sites in DDX5, one in the N-terminal region of amino acids 1 to 384 and the other in the C-terminal region of amino acids 387 to 614. Proteins spanning different regions of DDX5 were expressed and purified for crystallization trials. The N-terminal region of DDX5 from amino acids 1 to 305 which contains the conserved domain I of the DEAD-box helicase was also cloned and expressed in Escherichia coli. The cloning, expression, purification and crystallization conditions are presented in this work. Subsequently, the crystal structure of DDX5 1-305 was solved and the high resolution three-dimensional structure shows that in front of domain I is the highly variable and disordered N terminal region (NTR) of which amino acids 51-78 is observable, but whose function is unknown. This region forms an extensive loop and supplements the core with an additional α-helix. Co-immunoprecipitation experiments demonstrated that the NTR of DDX5 1-305 auto-inhibit its interaction with NS5B. Interestingly, the α-helix in NTR is essential for this auto-inhibition and seems to mediate the interaction between the highly flexible 1-60 residues in NTR and NS5B binding site in DDX5 1-305, presumably located within residues 79-305. Furthermore, co-immunoprecipitation experiments revealed that DDX5 can also interact with other HCV proteins, besides NS5B.
84

PROCESSOS DE SEPARAÇÃO DE MATERIAIS VALIOSOS DE TELAS LCD DE TELEFONE CELULAR / SEPARATION PROCESS OF VALUABLE MATERIALS FOR LCD SCREENS OF CELL PHONE

Fuchs, Miria da Silva 25 July 2013 (has links)
Fundação de Amparo a Pesquisa no Estado do Rio Grande do Sul / The proposal of this work is separate the liquid crystal display (LCD) screen of cell phones in disuse, removing polymers which are adhered to the glass screen by using an appropriate solvent, and then perform the glass comminution to leaching the metal oxides that form part of the composition of the LCD screens of cell phones, as well as the screens of televisions, computers, digital clocks and other devices that have liquid crystal displays. With these proceedings, the polymeres, glass and metallic oxides are separated and can be recovered and reused, avoiding the consumption of non-renewable raw materials. Several tests are made under different conditions of temperature, time, ratio solute/solvent, particle size comminution and acid concentration in the leaching. The amount of indium and tin present in LCD screens, in the form of indium tin oxide (ITO) is analyzed in an apparatus for atomic absorption flame, which provides the same amount of the leaching solution. Compared with the amount of indium extracted in a solution of aqua regia 1:20, considered the condition of maximum extraction metal oxides, the quantity of indium recovered, in 1M sulfuric acid solution in 1:10 at 90ºC for 2 hours with those procedures was 98,74%. / A proposta deste trabalho é de separar, através de um desmantelamento manual, a tela de LCD de aparelhos celulares em desuso e, posteriormente, retirar os polímeros que ficam aderidos à superfície do vidro da tela com o uso de um solvente adequado, em seguida realizar a cominuição do vidro para a lixiviação dos óxidos metálicos que fazem parte da composição das telas de LCD de aparelhos de telefones celulares. Com estes procedimentos são separados polímeros, óxidos metálicos e o vidro, que podem ser recuperados e reutilizados, evitando o consumo de matérias-primas não renováveis. Foram testadas condições diferentes de temperatura, tempo, proporção soluto/solvente, tamanho de partículas cominuídas e concentração ácida nas lixiviações. A concentração de índio e de estanho presente nas soluções obtidas na lixiviação das telas de liquid crystal display (LCD) que contém óxido de estanho e índio (ITO) foi determinada pela técnica de absorção atômica (AAS). Em comparação com a quantidade de índio extraída em uma solução de água régia utilizando uma relação sólido-líquido de 1:20, considerada a condição de extração máxima dos óxidos metálicos, a quantidade de índio recuperada em solução de ácido sulfúrico 1M, na proporção 1:10, a 90ºC por 2 horas e sob agitação, foi de 98,74%.
85

Měření pozice elektronickými dotykovými sondami / Position measurement by electronic contact probes

Noga, Kamil January 2018 (has links)
This work is dealing with custom screens programming for Mitsubishi M7 series controller. These custom screens will be working as graphic user interface for easy workpiece zero position measuring and also for precise measuring of length and diameter of tools used for working on the work piece.
86

Návrh informačního systému / Information System Design

Kolář, Jiří January 2014 (has links)
This thesis discusses informatik systems in companies, their technologies and new trends in hardware domain, used to simplify, speed up and streamline business processes. Consequently thesis deals with the extension of an information system in a real environment, aimed to getting more detailed data, processing and subsequent evaluation to adjustable reports.
87

Thermal characteristics of screenhouse configurations in a West-African tropical climate.

Desmarais, Gaetan January 1996 (has links)
No description available.
88

Genome-Wide In Vivo CRISPR Activation Screen to Identify Genetic Drivers of Non-Small Cell Lung Cancer Brain Metastasis

Aghaei, Nikoo January 2021 (has links)
Brain metastasis (BM), the most common tumor of the central nervous system, occurs in 20-36% of primary cancers. In particular, 20-40% of patients with non-small cell lung cancer (NSCLC) develop brain metastases, with a dismal survival of approximately 4-11 weeks without treatment, and 16 months with treatment. This highlights a large unmet need to develop novel targeted therapies for the treatment of lung-to-brain metastases (LBM). Genomic interrogation of LBM using CRISPR technology can inform preventative therapies targeting genetic vulnerabilities in both primary and metastatic tumors. Loss-of-function studies present limitations in metastasis research, as knocking out genes essential for survival in the primary tumor cells can thwart the metastatic cascade prematurely. However, transcriptional overexpression of genes using CRISPR activation (CRISPRa) has the potential for overcoming dependencies of gene essentiality. In this thesis, we created and utilized an in vivo genome-wide CRISPRa screening platform to identify novel genes, that when overexpressed, drive LBM. We have developed a patient-derived orthotopic murine xenograft model of LBM using a patient-derived NSCLC cell line (termed CRUK cells) from the Swanton Lab TRACERx study. We introduced a human genome-wide CRISPRa single guide RNA (sgRNA) library into non-metastatic and pro-metastatic lung cancer CRUK cells to achieve 500X representation of each sgRNA in the activation library. We then injected the cells into the lungs of immunocompromised mice and tracked lung tumor development and BM formation. Upon sequencing primary lung tumors and subsequent BM, we will identify enriched sgRNAs which may represent novel drivers of primary lung tumor formation and LBM. To the best of our knowledge, this study is the first in vivo genome-wide CRISPR activation screen using patient-derived NSCLC cells to help elucidate drivers of LBM. This work serves to provide a framework to gain a deeper understanding of the regulators of BM formation which will hopefully lead to targeted drug discovery that will ultimately be used in clinical trials to help eradicate brain metastasis in NSCLC patients. / Thesis / Master of Science (MSc) / Brain metastasis, or the spread of a primary cancer from another organ to the brain, is the most common adult brain tumor. Brain metastases can arise after the treatment of primary tumors and are only detected in the clinic at a highly malignant stage. Current treatments for brain metastasis consist of surgical removal and palliative chemoradiotherapy, which fail to fully eliminate the brain tumor. Over 20% of cancer patients develop brain metastases, with lung, breast, and skin cancers leading as the top three sources of metastasis. In particular, 40% of patients with non-small cell lung cancer develop brain metastasis, with survival of only 4-11 weeks once diagnosed without treatment, and 16 months with treatment. As systemic therapies for the treatment of non-small cell lung cancer are becoming increasingly effective at controlling primary disease, patients are ironically succumbing to their brain tumors. This highlights a large unmet need to develop novel targeted therapies for the treatment of lung-to-brain metastases (LBM). Functional genomic tools provide the opportunity to investigate the genetic underpinnings of LBM. With the advent of gene editing technologies, we are able to overexpress various genes and observe the impact genetic perturbations have on tumor initiation, growth, and metastasis. In this thesis, we devised a pre-clinical animal model of LBM that could be used to study genetic drivers of LBM using a gene overexpression tool such that one gene per tumor cell gets activated. We are then able to model the disease trajectory from a lung tumor to brain metastasis development using patient samples in our animal model and identify genes that, upon overexpression, drive LBM. This platform will lead to potential therapeutic targets to prevent the formation of LBM and prolong the survival of patients with non-small cell lung cancer.
89

Design of a Vibrational Energy Harvesting System for Wireless Sensor Nodes

Wilson, Aaron M. E. 11 1900 (has links)
McMaster University in conjunction with an industrial partner has been designing wireless vibrational condition monitoring sensors for implementation on a vibrating screening machine used in mining applications. A limitation with the current sensor design is their dependency on battery power. In order for the sensors to provide real-time continuous streaming of acceleration data, an alternate power supply was required outside of traditional sources such as batteries or wired power. This thesis outlines the research and development of a power system that harvests the kinetic vibrational energy of a mining screen and converts it into electrical energy for use by a wireless sensor node. During development, multiple prototypes were built and evaluated under laboratory conditions. The core concept of the system is an eccentric pendulum mass excited by the external vibrations of the screening machine used to drive a stepper motor generator. The major design obstacle of the project was how to get the system to self initiate. Both a mechanical and an electrical solution were developed to solve this concern. The final prototype design is fully autonomous, able to react to the start up or shut-down of a screening machine, while also providing a continuous power supply to a wireless vibrational analysis sensor as tested in the lab. With minor optimization, this prototype can be turned into a commercial product for industrial implementation and sale. / Thesis / Master of Applied Science (MASc)
90

ANALYSIS OF MARBURG VIRUS PROTEIN INTERACTIONS

Veronica J Heintz (13176234) 29 July 2023 (has links)
<p>  </p> <p>Infection by Marburgvirus (MARV) or the closely related Ebolavirus (EBOV) results in potentially lethal hemorrhagic fever in humans characterized by uncontrolled viremia, a systemic pro-inflammatory response, and multi-organ failure. Currently, there are no approved countermeasures to treat or prevent MARV infection, which leaves a critical need for development of antiviral therapies. One approach to develop antiviral therapies is exploit a virus’s dependency on the host cell and disrupt critical human-viral interactions. While multiple studies identified host-viral interactions involved in EBOV infection, we are currently limited in our knowledge of host-viral interactions that occur during MARV infection and how these interactions influence the viral replication cycle. Thus, the purpose of this research was to identify and further characterize the biological significance of human-MARV protein-protein interactions that occur during infection.</p> <p>Here, we used genome-wide yeast two-hybrid (Y2H) screens to identify directly interacting human-viral proteins. We identified 431 putative interactions with MARV and used a combination of a novel NanoLuc Y2H assay and confidence criteria to prioritize a final set of 396 interactions. Bioinformatic analysis revealed that the molecular functions of the interacting human genes were significantly enriched in RNA binding, cell adhesion, and cytoskeleton binding. </p> <p>MARV and EBOV have many similarities in their genomic organization, sequence, and protein structures that could facilitate interactions to common host factors during infection. Thus, to identify shared interactions between these related viruses, we compared the MARV interactions to EBOV interactions identified in a parallel Y2H screen. We identified 145 human proteins targeted by both MARV and EBOV. The majority (77%) of shared interactions occurred between homologous viral proteins. Additional bioinformatic analyses comparing MARV and EBOV interactions revealed that these viruses interact with different host factors with similar molecular functions (RNA binding, DNA binding, actin and microtubule binding. Together, these data support the notion that while MARV and EBOV target common host factors there are still differences in protein interactions that support functions specific to each virus. </p> <p>To investigate the biological significance of the identified interactions, we focused on host interactions with the viral matrix protein, VP40. VP40 is a multifunctional protein that facilitates viral assembly and budding from the host cell. Y2H assays using VP40 mutants revealed that the WW-containing host protein MAGI1 interacted with the late domain of VP40. This interaction was validated in mammalian cells using coimmunoprecipitation and GFP complementation assays. Based on multiple reports of WW-containing host proteins interacting with VP40, we predict that the interaction between MAGI1 and VP40 regulates viral budding.</p> <p>In conclusion, the work presented here successfully identified 396 novel human-MARV interactions, which furthers the field’s understanding of host factors involved in MARV infection. Additionally, we identified interactions shared by MARV and EBOV, which could be beneficial in the development of a broad antiviral therapy against filoviruses. Lastly, we validate the interaction between MAGI1 and VP40, which has a potential role in viral budding </p>

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