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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.
171

Vigilância virológica dos vírus dengue: genotipagem e caracterização molecular de vírus isolados em mosquitos naturalmente infectados e humanos, 1986-2011

Castro, Márcia Gonçalves de January 2012 (has links)
Submitted by Alessandra Portugal (alessandradf@ioc.fiocruz.br) on 2013-09-17T16:29:26Z No. of bitstreams: 1 Tese_Marcia de Doutorado DEFINITIVA - Para entregar no PGBP.pdf: 21978043 bytes, checksum: 1d029677a684e2e22915d3841a8206d3 (MD5) / Made available in DSpace on 2013-09-17T16:29:26Z (GMT). No. of bitstreams: 1 Tese_Marcia de Doutorado DEFINITIVA - Para entregar no PGBP.pdf: 21978043 bytes, checksum: 1d029677a684e2e22915d3841a8206d3 (MD5) Previous issue date: 2012 / Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Rio de Janeiro, RJ, Brasil / O dengue tem se apresentado como um grave problema de saúde pública no Brasil, razão pela qual, vários estudos têm sido realizados com o intuito de esclarecer aspectos da epidemiologia dessa doença em diferentes localidades, com histórias distintas de circulação dos diferentes sorotipos dos vírus dengue (DENV). A implantação de um Programa de vigilância entomológica e virológica e, que desde 1986 visa detectar e monitorar a circulação dos sorotipos e genótipos DENV, resultou em distintas oportunidades, no isolamento de amostras de DENV de vetores e de casos humanos permitindo a caracterização molecular e a análise filogenética, fornecendo informações relevantes para a compreensão da interação vetor- vírus- humanos. O entendimento da variação genética no vírus quando este replica em mosquitos, e como essas variações atuam durante a transmissão entre humanos e mosquitos permanecem desconhecidos. Portanto, visando contribuir para um melhor conhecimento dos DENV e sua interação com o mosquito vetor, realizamos neste trabalho, a caracterização molecular e análise filogenética de DENV isolados de mosquitos naturalmente infectados e de casos humanos, provenientes de epidemias ocorridas entre 1986 e 2011 no Brasil. Foi demonstrado que os métodos moleculares foram fundamentais por facilitarem a rápida identificação dos vírus e consequentemente o monitoramento dos genótipos circulantes. A RT-PCR para a triagem de DENV em vetores se mostrou uma ferramenta útil para a vigilância virológica, com taxas de detecção que variaram de 0,78% a 25% no período estudado. A análise filogenética dos DENV-1 isolados de mosquitos e humanos mostrou que o genótipo V (Américas/África) continua o mesmo circulante desde a sua introdução, porém foi demonstrada a co-circulação de duas novas linhagens (II e III) no período de 2009 a 2011. O sequenciamento do genoma completo de DENV-3 isolado a partir de Ae. aegypti naturalmente infectados no Rio de Janeiro (RJ), assim como a análise da região 3´NC de vírus isolados em mosquitos e humanos, caracterizou estes vírus como pertencentes ao GIII e revelou a presença de inserções e deleções na região 3´NC do genoma. As deleções observadas na região 3´NC resultaram em estruturas secundárias porém nem todas as cepas com inserções nesta região apresentaram estrutura similar substituições exclusivas à cepa de DENV-3 isolada em mosquito foram observadas no gene NS5, incluindo a substituição que resultou na formação de um códon de terminação. O teste comercial Simplexa™ Dengue Real Time RT-PCR, disponível recentemente, foi utilizado pela primeira vez para detecção dos DENV e se mostrou um método molecular alternativo para as vigilâncias entomológica e virológica. O RT-PCR em Tempo Real possibilitou, pela primeira vez, a quantificação de DENV-1 e DENV-4 em fêmeas individuais naturalmente infectadas (1,6 x 104 cópias/mL e 1,08 x 103 cópias/mL, respectivamente). Considerando-se o elevado índice de infestação por Ae. aegypti em todo o país, o estudo da caracterização dos DENV circulantes torna-se de grande importância no conhecimento da relação vírus-vetor pela análise da variabilidade genética, dispersão e persistência de genótipos durante a transmissão destes vírus / Dengue has been a major public health problem in Brazil with several studies performed aiming to elucidate the disease epidemiology in geographically distinct areas with different dengue viruses (DENV) circulation. The establishment of an entomological and virological program since 1986 with the objective of detecting and monitoring DENV serotypes and genotypes resulted in distinct opportunities in DENV isolation from vectors and human cases, allowing the molecular characterization and phylogenetic analysis, providing relevant information for the understanding of the vector-virus-humans interactions. The understanding of the virus genetic variability when it replicates on mosquitoes and how those variations act during the transmission between humans and mosquitoes is not fully understood. Therefore, aiming to contribute for a better understanding of DENV and its interactions with the mosquito vector, we performed in this study the molecular characterization and phylogenetic analysis of viruses isolated from naturally infected mosquitoes and human cases, from epidemics occurred between 1986 and 2011 in Brazil. It has been shown that the molecular techniques were essential for allowing the rapid identification of the viruses and consequently the monitoring of the circulating genotypes. The RT-PCR for DENV screening in vectors has shown to be a useful tool for the virological surveillance, with detection rates varying from 0.78% to 25% in the studied period. The phylogenetic analysis from DENV-1 isolated from mosquitoes and human cases showed that genptype V (America/Africa) is still the same genotype circulating since this serotype introduction, however it was demonstrated the co-circulation of two distinct new viral lineages (II and III) from 2009 to 2011. The complete genome sequencing of a DENV-3 isolated from naturally infected Ae. aegypti in Rio de Janeiro (RJ) and the analysis of the 3´UTR region from viruses isolated from mosquitoes and humans, has characterized those viruses as belonging to genotype III (GIII) and revealed the presence of insertions and deletions in the 3´UTR region of the genome. The deletions observed in the 3´UTR region resulted in similar secondary structures, however not all strains with insertions were similar in structure. Exclusive substitutions to the DENV-3 isolated from the mosquitoes were observed in NS5, including a substitution leading to a stop codon formation. The Simplexa™ Dengue Real Time RT-PCR commercial kit, recently available, was used for the first time for DENV detection and it has been shown to be an alternative molecular method for the entomological and virological surveillances, The Real Time RT-PCR has allowed, for the first time the DENV-1 and DENV-4 quantification in single Ae. aegypti naturally infected (1.6 x 104 copies/mL e 1.08 x 103 copies/mL, respectively). Considering the high Ae. aegypti infestation index in the country, the characterization of DENV circulating is very relevant for the understanding of the virus-vector relations by the analysis of the genetic variability, spread and persistence of genotypes during the transmission of those viruses
172

Mitteilungen des URZ 2/1997

Bobber,, Gerber,, Graupner,, Huebner,, Mueller,, Sontag,, Voigt, 29 July 1997 (has links)
Intranet - Erwartungen und Entwicklungen JavaOS - ein Betriebssystem fuer Intranets Network Computer - Eine Verkaufsstrategie? Was gibt es schon? Netscape IFC's - Gestalten von graphische Nutzerinterfaces WWW-Sicherheitsaspekte - ein heisses Thema: Sicherheit im Netz Aufbau einer Certification Authority - z.B. IN e.V. Chemnitz Authentisierung und Verteilung von Konfigurationsfiles - am Bsp. URZ
173

Synthesis and characterization of magnetron sputtered thin films of the Ti-Al-Si-N(O) system

Godinho, Vanda 18 February 2011 (has links)
The aim of this Thesis was on one side to contribute to a better understanding of the phases formed in the TiAlSiN(O) system and the influence of impurities on their properties. On the other side it was also aimed in the Thesis to individually study the phases forming the nanocomposite. <p><p>In each chapter the individual conclusions from that particular chapter are presented, a summary of the most relevant conclusions and achievements is listed below. <p><p><p>¡à\ / Doctorat en Sciences de l'ingénieur / info:eu-repo/semantics/nonPublished
174

Atypické využití karuselového soustruhu / Atypical use of a carousel lathe

Ondráček, Ivo January 2018 (has links)
The first part of the diploma thesis deals with a brief research of turning operations and the characteristic of vertical lathes with description of individual parts. There are described possibilities and a typical vertical lathe assortment and also representatives of Czech manufacturers of vertical lathes. In the second part, the thesis deals with elaboration of the design technology production of the selected component, including the NC program. First, a component and material is selected, a semi-finished product is designed, suitable machines and tools are selected and finally a technological process of production is developed. The conclusion of the thesis contains the technical–economic evaluation, where the total costs of production are solved.
175

Počítačem řízená frézka / Milling machine

Homola, Stanislav January 2015 (has links)
This goal of the diploma thesis is to design, to construct and write control program for CNC milling machine designed for machining aluminum, wood and plastic. Entire structure of machine is designed and made of steel. The main table consists of an aluminum plate and aluminum structural profiles. Spindle of milling machine is a high speed motor from ATAS a.s. company. Milling machine is controlled by the program made in TwinCAT environment from Beckhoff Automation GmbH & Co. KG.
176

Možnosti systému Sinumerik při programování rotační strojní součásti / Sinumerik tools for programming of rotational machine part

Slavík, Daniel January 2014 (has links)
This diploma thesis deals with a manufacture of rotating mechanical component on CNC lathe machine with Sinumerik control system. At first the chosen component is briefly described and then NC program is created in Sinutrain Operate 4.5 system. Afterwards the program is verified by simulation. Within the diploma thesis a technological documentation is elaborated that contains a new technological course of manufacture and a manufacture drawing of the component. The final part of this thesis is focused on technical-economic evaluation of newly designed manufacture with verification of cutting conditions and required output of the CNC machine. The outcome of the thesis defines an hour rate of CNC lathe and price of component that regards to newly presented manufacture.
177

Lokalisering av arbetsstycke för CNC-maskiner : Undersökning av alternativa givare / Workpiece Localisation for CNC machine : Investigation of alternative sensors

Berlin, Leonard, Vendel, Jonas January 2022 (has links)
I takt med att CNC-fräsmaskiner blivit mer tillgängliga för allmänheten, växerbehovet av billiga alternativ till marknadsledande mätprobar (TTP). Generiska sensorer med öppen hårdvara finns tillgängliga till låga priser, men det är okäntom en sensor för under 100 kr kan användas som komponent i en mätprob, där noggrannhetskravet kan vara i storleksordningen mikrometer. Detta skulle isåfallinnebära att det finns en möjlighet att tillverka mätprobar till tillgängligare priser än dagens marknadsledande probar. Denna studie avsåg att undersöka ifall dessa sensorer var lämpade för ändamålet. Därför bedömdes ett antal Arduinokompatibla sensorer utifrån deras prestanda och lämplighet som komponent i en automatisk mätprob för arbetsstyckeslokalisering i CNC-fräsmaskiner. Sensorerna och principerna som undersöktes var: mikrobrytare, induktiva sensorer, ultraljudssensorer, IR-sensorer och kontinuitetssensorer. Sensorerna testades i en fräsmaskin och deras spridning estimerades genom att beräkna standardavvikelsen hos mätdatan. Efter en litteratursökning och intervjuer med KTHs akademiker samt den tänkta målgruppen för mätproben Stockholm Makerspace, bekräftades kravbilden på sensorn. Där belystes vikten av det låga priset på slutprodukten samt ett krav på att osäkerheten ska vara runt 0.05 mm. Mikrobrytaren konstaterades vara den lämpligaste sensorn. Detta beror på dess låga pris, oberoendet av materialet på arbetsstycket och den höga repeterbarheten. Repeterbarheten beräknades vara 5 μm med en konfidensintervall på 95%. / Since CNC-milling machines have become more accessible to the public, so has the demand for economical alternatives to the market-leading product, Trigger Touch Probes (TTP). Generic sensors with open hardware are now obtainable for a low price, but it is unknown if a sensor with a cost of under 100 SEK can be used as a component in a measuring instrument. Especially where the required accuracy lies in microns. If that is the case, it would be possible to manufacture TTP at more accessible prices than the current standard. This study aimed to answer whether the low cost sensors were suitable for this application. A number of Arduino compatible sensors were therefore evaluated in terms of performance and suitability as a component in an automated measurement probe for workpiece localization in CNC-machines. The sensors/ principles that were evaluated were: micro switches, inductive sensors, ultrasound sensors, IR-sensors, and continuity sensors. The sensors were tested in a milling machine and their statistical dispersion (scattering) were estimated by calculating the standard deviation of the data. After a literature study and interviews with academia from KTH and the intended customer, Stockholm Makerspace, the requirements on the probe were decided. The importance of the low cost of the final product were brought to attention and the requirement of a variance around 0.05 mm. The micro switch was evaluated to be the most suitable sensor due to the low price, high repeatability, and the fact that it was independent of the workpiece’s material. The repeatability was measured to be 0.0052 mm with a confidence interval of 95%.
178

Assessment of Machine tool flexibility in a Production system

Oldestam, Anton January 2023 (has links)
This project aims to present machine tool characteristics which may induce limiting factors in terms of flexibility. The aim is also to present a current state description of the machine tools in the production system regarding their characteristics in terms of quantifiable results. This refers to visual presentation in the form of graphs of the distribution of these characteristics among the different machine tools. A literature study was conducted to attain knowledge of machine tools and how the literature defines machine tool flexibility. Based on this, the flexibility parameters were identified. The result illustrates the current state description of the machine tools found in Volvo truck’s factory in Köping. These machine tools are lathe machines, machine centers, gear cutting machines and grinding machines. The result presents a percentage breakdown for each parameter for each of the machine types regarding the number of machines which possess a specific characteristic. The result displayed various cases of data missing. In many cases only a small percentage of data was missing, thus this result should be a sufficient representation of the situation. Meanwhile in other cases more data was missing and it leads to the result being less accurate. Overall, the acquired data in most cases should be sufficient to provide a current state description of the machines in the factory. There is no clear definition of flexibility referenced by the literature, hence it is difficult to conduct a quantitative evaluation. Moreover, there are many parameters presented in this work which emphasizes the multidimensional complexity of the problem. The parameters presented in this project directly influence the type of operations required, geometrical complexity of the workpiece, number of setups and size of workpiece which the machine is capable of handling. The machines have been grouped into the four categories mentioned above. This was done to reduce the complexity of the problem, hence not investigating each sub-category of machine (for example hobbing, skiving, etc.) The work has chosen not to group the machines based on the article they process as this would require additional knowledge of the layout and flow of material in the factory. The chosen approach will provide more of a generic visualization. A method has been developed to present a current state description of a manufacturing system regarding machine tool flexibility and how they can be evaluated. This process includes data collection and documentation of machines tools for the flexibility parameters. Hence, it can be presented how the machines within each machine type possess a specific attribute in terms of numbers or fit within a certain interval. The purpose is to present visual results of the data to illustrate for the reader the distribution of the machine characteristics for each of the machine types and parameters. / Detta projekt har som mål att presentera egenskaper hos bearbetningsmaskiner som kan medföra begränsande faktorer kopplat till flexibilitet. Målet är också att presentera en nulägesbeskrivning av bearbetningsmaskinernas egenskaper i produktionssystemet i form av kvantifierbara resultat. Detta refererar till visuella presentationer i form av grafer angående distribueringen av dessa egenskaper bland de olika bearbetningsmaskinerna. En litteraturstudie har genomförts för att tillhandahålla kunskaper om bearbetningsmaskiner och hur litteraturen definierar flexibilitet hos bearbetningsmaskiner. Resultatet illustrerar nulägesbeskrivningen av bearbetningsmaskinerna som befinner sig i Volvo Trucks fabrik i Köping. Dessa bearbetningsmaskiner är svarvar, fleroperationsmaskiner, kuggbearbetningsmaskiner och slipmaskiner. Resultatet visar en procentuell uppdelning av varje parameter for varje maskintyp, angående antalet maskiner som besitter en viss typ av egenskap. Resultatet visade på olika fall av saknad av data. I många fall saknades endast en liten andel av data, därmed bör detta resultat ge en tillräcklig representation av situationen. I andra fall saknades mer data och det leder till att resultatet blir mindre exakt. Överlag bör den insamlade datan i de flesta fall vara tillräcklig för att presentera en nulägesbeskrivning av maskinerna i fabriken. Det finns ingen tydlig definition av flexibilitet som nämns i litteraturen, därmed medför detta svårigheter att utföra en kvantitativ utvärdering. Dessutom presenteras det många olika parametrar i detta arbete, vilket understryker problemets flerdimensionella komplexitet. Parametrarna presenterade i detta arbete påverkar direkt vilken typ av operation som behövs, geometriska komplexiteten av arbetsstycket, antalet uppspänningar och storleken på arbetsstycket som maskinen kan hantera. Maskinerna har grupperats i fyra olika kategorier som nämndes ovan. Detta gjordes för att minska komplexiteten av problemet, därmed undersöks inte underkategorierna av maskinerna (till exempel hobbing skiving etcetera). Arbetet har valt att inte gruppera maskinerna baserat på vilken artikel de bearbetar, eftersom detta skulle behöva ytterligare kunskaper om layouten och flödet av material i fabriken. Det valda tillvägagångssättet ger en mer generell visualisering. En metod har tagits fram för att presentera en nulägesbeskrivning av ett produktionssystem med avseende på flexibiliteten hos bearbetningsmaskiner och hur de kan utvärderas. Denna process inkluderar datainsamling och dokumentation av flexibilitetsparametrarna hos bearbetningsmaskinerna. Därmed kan det presenteras hur maskinerna inom varje maskintyp besitter en specifik egenskap i form av siffror eller passar inom ett specifikt intervall. Syftet är att presentera visuella resultat av datan för att illustrera för läsaren om distribueringen av maskinegenskaperna för varje maskintyp och parameter.
179

A multidisciplinary study of the Asiatic clam, Corbicula fluminea, from the New River, Virginia

Doherty, Francis G. January 1986 (has links)
Studies were conducted with the Asiatic clam, Corbicula fluminea, that examined seasonal periodicities in spawning, body condition, and percent tissue water content. In addition, responses of adults to brief (24 hr) and extended (30 d) periods of exposure to toxicants were investigated. These studies addressed the valve closure behavioral response by adults exposed to chlorine, cadmium, and zinc; the effects of these pollutants and temperature on the levels of metal binding protein in adults; and the efficacy of halogens ( chlorine and bromine) in providing acceptable levels of Asiatic clam biofouling control. Spawning periodicity of C. fluminea was monitored weekly for 8 months in 1984. Observations revealed that spawning occurred on three distinct occasions with peaks in release of veligers in June, August, and October. Percent tissue water content and body condition were monitored monthly in 1985. Significant differences in these parameters were observed among certain months and among size classes. Tissue water content and body condition in the largest individuals were inversely related. Periods of activity (valves parted) and quiescence (valves closed) were determined in the absence and presence of toxicants by continuously monitoring valve movement patterns. Data indicate that the duration of activity periods and toxicant exposure concentration are inversely related. Application of these observations to efforts to control Asiatic clam fouling in industrial water lines resulted in a reduction in the total levels of molluscicide required. Exposure of clams to low levels of chlorine (0. 25 mg/L total residual chlorine) induced valve closure that resulted in weakened clams after two weeks that were more susceptible to increased levels of chlorine. The levels of a metallothionein-like metal binding protein (MBP) in tissues of Q. fluminea following exposure to metal and non-metal stressors were also assessed. In general, exposure to dissolved cadmium resulted in significantly greater levels of MBP than either dissolved zinc, chlorine, or temperature extremes (4°, 30°C). Analysis of individual organ groups demonstrated an inverse relationship between sites of MBP synthesis ( gills, mantle, and adductor muscles versus visceral mass) and mode of exposure to cadmium (dissolved versus food associated). / Ph. D.
180

eXplicit Content: A Discussion of the MPAA Film Rating System and the NC-17 Rating

Miller, Caroline H 01 January 2015 (has links)
The United States film industry is controlled by the Motion Picture Association of America (MPAA) and its six signatories--the major productions studios (Sony, Warner Brothers, Universal, Walt Disney, 20th Century Fox, Time Warner), and through this joint-partnership they have monopolized prime production, distribution, exhibition and classification of the U.S film market. The objective of this project is to shed light on biases present in the MPAA rating system's treatment of sex and violence under the X/NC-17 rating in order to demonstrate the lack of viability of the system in today's world.

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