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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

Étude de la protéine sigma 1 de réovirus par génétique inverse

Brochu-Lafontaine, Virginie 04 1900 (has links)
No description available.
172

Ovlivnění plazmatické hladiny cholesterolu modelového organizmu polynenasycenými mastnými kyselinami n-3

Čeganová, Markéta January 2014 (has links)
The aim of this thesis is to assess the influence of the polyunsaturated fatty acids, especially DHA and EPA in the diet on the animal organism in accordance to the levels of total HDL and LDL cholesterol and triglycerides in plasma. As experimental animals were used rats and they were divided into 3 groups of 10 pieces: control group with the addition of 6 % Carthamus tinctorius (n-6 flares), the group with the addition of 6 % fish oil (n-3: EPA, DHA fish) and the group with 6 % addition of oil from Schizochytrium (n-3: DHA, DHA). After 40 days the animals were putted to death according to relevant regulations. Blood lipids were obtained from blood samples by spectrophotometry. Value of polyunsaturated fatty acids of n-3 and n-6 was set by gas chromatography in the liver, muscle and adipose tissue. In accordance to the increase of content n-3 PUFA in group with fish oil and with oil from Schizochytrium, total and LDL cholesterol was reduced in comparison of samples in control group. In comparison to the control group were TAG reduced only in the group with addition of oil.
173

RFID technologie a její použití ve zvoleném podniku / RFID Technology and its Use in Selected Enterprise

Brožová, Natálie January 2016 (has links)
This thesis focuses on the topic of RFID - radio frequency identification of objects. The theoretical part is focused on the definition and history of RFID systems, the main components of this technology, regulation and standards in the use of RFID, categories of RFID and its implementing into business processes. The theoretical part also describes the costs of RFID, potential benefits arising from its implementation and examples of areas in which RFID technology is applied. The practical part deals with the implementation of RFID in a particular company and describes situation of the company before and after the RFID implementation. Furthermore, practical part summarizes the results of interviews with employees of the company and a listing of key benefits that RFID has brought. At the end of the practical part the author proposes some improvements to the existing use of RFID system.
174

Expressão gênica diferencial em palmitos de cana-de-açúcar submetida a diferentes períodos de estresse hídrico /

Jovino, Daniele Fernanda Revoredo. January 2007 (has links)
Resumo: Sob condições de estresse hídrico, a cana-de-açúcar pode sofrer mudanças fisiológicas e bioquímicas, tais como diminuição nas atividades fotoquímicas, redução da fixação de CO2 e acúmulo de osmólitos e osmoprotetores. O objetivo deste trabalho foi identificar, através da técnica de macroarranjo de cDNA, o perfil de expressão de genes promotores das diferentes vias metabólicas em palmitos da variedade de cana-de-açúcar SP80-3280 submetidas ao estresse hídrico nos dias 5, 9, 13 e 17 após o início da condição de supressão de água, sendo considerado o dia 1 como controle. Os resultados do macroarranjo mostraram que as proteínas mais expressas sob déficit hídrico pertencem a quatro categorias das quais as ESTs mais importantes foram selecionadas. As quatro categorias descritas abaixo estão discutidas neste trabalho. As ESTs da via do metabolismo de açúcar e amido (invertase de parede celular (INV), sacarose fosfato sintase (SFS), sacarose fosfato fosfatase (SFF), trealose fosfato sintase (TFS), trealose fosfato sintase/fosfatase (TFS/F) e hexoquinase (HXQ)) pertencem a categoria de bioenergética. Colina monooxigenase (CMO) e betaína aldeído desidrogenase (BADH) as quais pertencem a via do metabolismo de glicina betaína, foram selecionadas a partir da categoria do metabolismo secundário. A terceira categoria compreende as ESTs do metabolismo de aminoácido (D-pirrolina-5- carboxilato sintase (P5CS), ornithina -aminotransferase (OAT) e prolil 4-hidroxilase (PH)) as quais pertencem a via da biossíntese de prolina, e a quarta categoria, resposta ao estresse, compreende as ESTs aleno oxido sintase (AOS), aleno oxido ciclase (AOC) e lipoxigenase (LOX), pertencentes a via de biossíntese do jasmonato. / Abstract: Under water deficit, sugarcane undergoes physiological and biochemical alterations such as photochemical activity reduction, CO2 fixation reduction and the accumulation of osmolytes and osmoprotectants. This work was undertaken to identify the gene expression profile in sugarcane (var. SP80-3280) under water deficit through the cDNA macroarray technique. Leafroll tissues were collected from plants subjected to 5, 9, 13 and 17 days of water restriction, and day 1 was used as control. Macroarray results showed that most proteins expressed under water restriction belong to four categories, from which the most important ESTs were selected. The four categories described below are discussed in this work. Sugar and starch metabolism pathway ESTs (cell wall invertase (CWI), sucrose phosphate synthase (SPS), sucrose phosphate phosphatase (SPP), trehalose phosphate synthase (TPS), trehalose phosphate synthase phosphatase (TSP/P) and hexoquinase (HXQ) were selected from the bioenergetics category. Choline monooxygenase (CMO) and betaine aldehyde dehydrogenase (BADH), which belong to the glycine betaine metabolism pathway, were selected from the secondary metabolism category. The third category comprised the amino acid metabolism ESTs D- pyrroline-5-carboxylate synthase (P5CS), Ornithine - aminotransferase (OAT) and Prolyl 4-hydroxylase (PH), which belong to the proline biosynthesis pathway, and the fourth category, stress response, comprised the ESTs for Allene oxide synthase (AOS), Allene oxide cyclase (AOC) and Lipoxygenase (LOX), which belong to the jasmonate biosynthesis pathway. / Orientador: Maria Inês Tiraboschi Ferro / Coorientador: Sonia Marli Zingaretti / Coorientador: Roberto Willians Noda / Banca: João Suzuki / Banca: Poliana Fernanda Giachetto / Mestre
175

Microbiota intestinal e assinatura isotópica de adultos de Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) como marcadores para a identificação da fonte alimentar de imaturos / Spodoptera frugiperda adult gut microbiota and isotopic signature (J.E. Smith) (Lepidoptera: Noctuidae) use as molecular markers to identify larvae food source

Adrian Augusto Sosa Gómez Rolim 07 November 2014 (has links)
A correta adoção de medidas de manejo de resistência de insetos-pragas é motivo de preocupação constante, inclusive para as novas tecnologias disponíveis, como as plantas geneticamente modificadas para a expressão de toxinas da bactéria Bacillus thuringiensis (Bt). Portanto, para manter a eficiência das plantas-Bt comercialmente disponíveis, é preconizada a manutenção de áreas de refúgio (livres de plantas Bt) para evitar a rápida seleção de insetos resistentes. No caso de insetos polífagos, a determinação das áreas de refúgio pode levar em consideração a contribuição que fontes não-comerciais e/ou não-transgênicas têm na produção de adultos colonizadores que não sofreram seleção para o evento de transgenia de interesse. A identificação da fonte alimentar pode determinar a procedência de insetos e tornar mais eficiente e segura a implementação de zonas de refúgio e a determinação dos riscos de desenvolvimento de resistência pelo inseto-praga alvo. O objetivo deste trabalho foi o de avaliar o potencial de dois marcadores biológicos, a assinatura isotópica e a microbiota intestinal, para a identificação da fonte de alimento do imaturo pela análise de adultos de Spodoptera frugiperda (J.E. Smith) (Lepidoptera, Noctuidae), como subsídio para o monitoramento da origem de insetos migrantes em áreas de cultivo Bt para a adoção de estratégias adequadas de manejo de resistência. A análise isotópica de adultos foi realizada utilizando-se insetos criados em 12 plantas hospedeiras distintas, seis de metabolismo C3 e seis de metabolismo C4. Parte dos adultos provenientes dessa criação foram liofilizados, macerados e submetidos à análise isotópica para a determinação dos níveis de ?13C e ?15N. Amostras das plantas utilizadas na alimentação desses insetos também foram submetidas ao mesmo processo de análise. A outra parte dos adultos recémemergidos de S. frugiperda foi utilizada para a determinação da microbiota intestinal pela análise de região do gene do 16S rRNA após sequenciamento em plataforma 454. Os resultados da análise isotópica de carbono para as plantas utilizadas como fonte alimentar apresentaram médias entre -31,37? e -25,07? para plantas C3 e entre -13,03? e -12,26? para plantas C4. Adultos de S. frugiperda oriundos de lagartas criadas em plantas do grupo C3 apresentaram média de ?13C entre - 30,36? e -23,72?, enquanto aqueles do grupo C4 apresentaram média entre - 18,25? e -13,28?. O sequenciamento da microbiota via metagenômica produziu 126,970 sequências com cerca de 421 pb. O alimento influenciou substancialmente a diversidade da microbiota intestinal associada ao intestino de adultos, independentemente do metabolismo fotossintético da planta hospedeira. Análises comparativas de diversidade em que a abundância relativa dos diferentes componentes foi considerada (Unifrac ponderado) permitiu a distinção de praticamente todas as microbiotas. Foram identificadas várias UTOs exclusivamente associadas à microbiota intestinal de adultos provenientes de cada fonte de alimento, mas a maioria apresentou abundância relativa extremamente baixa. Apenas as UTOs 1199 e 2255 foram exclusivamente associados ao milho com abundância relativa superior a 2,5%. / The correct insect resistant management has been a topic of constant concern, even for the newer technologies available, such as genetically modified crops expressing Bacillus thuringiensis (Bt) toxins. The use of refuge areas with non-Bt crops to avoid the fast selection for resistant insects is proposed for maintaining the efficiency of Bt-crops. The implementation of refuge areas for polyphagous insects can consider non-commercial and non-Bt crops as sources of susceptible insects. The identification of the food source used during immature development can make the implementation of refuge areas safer and more efficient and allow for better estimates of risk assessment for insect resistance development. The objective of this study is to determine the potential use of, the isotopic signature and gut microbiota of adults as biological markers to allow for the identification of the food source during the larval stage of Spodoptera frugiperda (J.E. Smith) (Lepidoptera, Noctuidae). Adults were obtained from larval rearing on 12 food sources, six host-plants with a C3 photosynthetic metabolism and six host-plants with a C4 metabolism. Part of the adults obtained and the food source used during their immature development were lyophilized and macerated, and subjected to ?13C e ?15N isotopic analysis. The remaining adults of S. frugiperda were used to determine the composition of the gut microbiota by metagenomic analysis of the V1-V3 region of the 16S rRNA gene using a 454 sequencing platform. The carbon isotopic signatures obtained for the hostplants used as food source were between -31.37? and -25.07? for C3 plants, and - 13.03? and -12.26? for C4 plants. Adults of S. frugiperda obtained from larval rearing on C3 plants had a carbon isotopic signature between -30.36? and -23.72?, while those from C4 host-plants has between -18.25? and -13.28?. The metagenomic sequencing yielded 126,970 reads with an average of 421bp. The larval food source substantially influenced the diversity of the adult gut microbiota regardless of the plant\'s photosynthesis metabolism. Comparative analysis among gut microbiota in which the relative abundance was taken into account (weight- Unifrac) allowed the discrimination of the majority of the communities. Several OTUs were identified as exclusive to the adult gut microbiota from different food sources, but most of these OTUs were minor components of the community. OTUs 1199 and 2255, both exclusively associated with corn, were the only ones to represent at least 2.5% of their community.
176

Interfaçage de bases de données photographiques et géographiques par appariement de lignes / Interfacing a photographic database and a geographical database by line matching

Attia, Youssef 31 August 2012 (has links)
Interfacer les photographies et les bases de données géographiques est une démarche utile pour les architectes, les historiens, les géographes mais aussi pour le grand public. Affecter une position géographique à une photographie permet en effet de décrire son contenu potentiel en s'appuyant sur les informations contenues dans une base de données géographique. L'objectif de la thèse est de proposer une méthode permettant de localiser automatiquement une photographie urbaine en la comparant avec des images de synthèse en 3D générées de manière systématique à partir d'un modèle virtuel des bâtiments. Le principe est que la photographie partage avec les images des caractéristiques géométriques qui permettent de les rapprocher et donc de déduire la localisation de la photographie à partir de la position connue de l'image. La méthode utilisée pour retrouver les images de synthèse correspondantes est un appariement entre les lignes présentes dans la photographie et les lignes détectées dans les images de synthèse par la transformation de Hough. Cet appariement est suivi par une analyse statistique permettant de proposer une localisation probable avec une valeur d'approximation associée.Malgré les obstacles présents dans les photographies, cette approche utilisant uniquement les lignes est une solution simple et potentiellement efficace pour le positionnement de photographies. Plusieurs scénarios d'usage sont proposés : la géolocalisation d'une image, la validation du positionnement d'une image localisée et l'utilisation de photographies pour repérer des changements dans le paysage urbain. / Interfacing photographs with geographic databases is a useful approach not only for architects, historians, geographers but also for a general audience. By assigning a geographical position to a picture it becomes possible to describe its potential content based on the information contained in the geographic database.The aim of the thesis is to propose a method to locate automatically an urban photograph by comparing this photograph with 3D images generated systematically from a virtual model of the buildings. The principle is to put in relation a photograph with the synthetic images that are sharing analog geometric characteristics and therefore to deduce the location of the photograph from the known position of the image. In order to nd synthetic images related to a photograph the method used is a matching between detected lines in the photograph and the images based on Hough transform. This matching is followed by a statistical analysis to propose a probable location with an estimation of accuracy. Despite the obstacles present in the photographs, this approach usingonly lines is simple and potentially effective for positioning photographs in urban space. Several scenarios of use are proposed : first location of an image, validation of the position of an image broadly located and use of photographs to identify change in the urban landscape.
177

Universal Tagging

Söderlund, Joakim January 2014 (has links)
The goal of this master degree project was to find out whether or not a highly integrated system for universal tagging of content improves the usability of a desktop environment. A prototype of such a system was implemented and integrated into the GNOME desktop environment. A usability study was then performed which showed that the tagging system did improve the usability of the desktop environment.
178

Real-time analysis of ring closing metathesis reactions

Liu, Jie 15 May 2018 (has links)
Ring closing metathesis (RCM) is a chemical transformation that converts a bisalkene compound into a cycloalkene. It is catalyzed by transition metal complexes containing carbene ligands (that feature metal-carbon double bonds). The mechanism is well-understood, however, there are numerous details of the reaction that are less well understood, especially concerning catalyst activation and decomposition and formation of byproducts. This thesis takes a new approach to the study of RCM: analysis of the reaction using real-time mass spectrometric techniques. Electrospray ionization (ESI) mass spectrometry was employed in this study, and the real-time aspect was enabled by using pressurized sample infusion (PSI). Observation of the reactants and products was enabled using charge-tagged bis-alkenes of the general formula [Bu2N{(CH2)nCH=CH2}2]+ [PF6]–. These were synthesized in two steps using a generally applicable methodology to generate a wide range of ring sizes of the product, from 5- to 15-membered rings. Examination of their behavior under carefully optimized RCM conditions using Grubbs’ second-generation catalyst showed a wide variation in reaction rates and amount of byproducts, largely due to ring-strain effects (especially high for 5- and 9-membered rings). Byproducts always exhibited a 14 Da mass unit difference from starting materials or products, and Orbitrap MS analysis confirmed it was CH2. Isomerization was suspected to lead to byproducts. A pathway for byproducts via isomerization and cross metathesis was proposed. The source of actual isomerization catalyst was believed to be from the precatalyst itself as the evidence of precatalyst decomposition was observed. Finally, to prove our isomerization hypothesis, an authentic isomerization catalyst was deliberately added into a fast and clean reaction along with Grubbs’ second-generation catalyst, and it produced the expected byproducts. Only small amounts of oligomeric intermediates were observed, probably because of the low concentrations used. [ClPCy3]+ was a new short-lived decomposition product stemming from catalyst breakdown, along with already-known imidazolium and protonated phosphine decomposition products. Overall, the thesis provides deep new insights into the nature of RCM reactions, in particular revealing the importance of isomerization in RCM reactions that are slow due to ring strain effects and in uncovering a new decomposition pathway for important RCM catalysts. / Graduate
179

Patterns of stance taking:negative yes/no interrogatives and tag questions in American English conversation

Keisanen, T. (Tiina) 25 April 2006 (has links)
Abstract This thesis reports on an empirical study of the forms and functions of two interrelated syntactic constructions, tag questions and negative yes/no interrogatives, in naturally occurring American English conversations. More specifically, the thesis focuses on examining the ways in which these interrogative constructions are involved in the intersubjective and interactional construction of stance. This involves describing the linguistic and interactional practices through which speakers index and negotiate their evaluative, affective or epistemic position or point of view towards some matter in the local context. The data used in the study comprise naturally occurring face-to-face and telephone interactions the majority of which take place between family and friends. The data are drawn from the first three published parts of the Santa Barbara Corpus of Spoken American English.The study is based on the methodological and theoretical principles of interactional linguistics and conversation analysis. The first part of the study provides an examination of the linguistic and grammatical patterning of the chosen constructions in a database of naturally occurring interactions in English. This serves first of all as a study of the general linguistic patterning of utterances with negation or reversed word order in interaction. At the same time, however, the grammatical and semantic categories of person, verb type and tense are employed for establishing the high frequency of linguistic and semantic material that index the current speaker's affective, evaluative and/or epistemic position towards the issue at hand. The second part of the study expands the focus from individual utterances to the surrounding interactional context in which the interrogative constructions are located, and makes use of the conversation analytic methodology. I examine how discourse participants use negative yes/no interrogatives and tag questions as a resource for carrying out different actions such as requesting for confirmation, challenging, disagreeing and assessing, and the ways in which interrogative speakers convey their epistemic, affective or evaluative stances in so doing. In this section of the study the research proceeds through detailed analyses of interaction, and an examination of those sequential environments in which the interrogative constructions are found.
180

Factors influencing nightly activity of deer mice (Peromyscus maniculatus) in tallgrass prairie

Rehmeier, Ryan L. January 1900 (has links)
Doctor of Philosophy / Department of Biology / Donald W. Kaufman / Glennis A. Kaufman / Little is known about nightly activity patterns of nocturnal small mammals under natural conditions, and how these activity patterns might be affected by photoperiod, season, and sex, age, and reproductive status of individuals. The main objectives of this research were: 1) to find an appropriate method for marking individual deer mice (Peromyscus maniculatus) so that their activity could be monitored remotely; 2) to design a portable activity-monitoring system to investigate temporal patterns of shelter use by deer mice under natural conditions; 3) to determine the influence of environmental conditions such as photoperiod and season on nightly activity of deer mice; and 4) to compare effects of demographic or physiological factors such as sex, age, and reproductive status on nightly activity of deer mice at artificial burrows in tallgrass prairie. In general, commencement of activity was correlated positively with timing of sunset, and time of retirement to the burrow was correlated positively with sunrise. Among adults, males first emerged from the burrow earlier and made more trips of shorter duration in a night than did females, although total duration of trips was similar. Return visits and subsequent stays typically were shorter for males than females, but total time spent in the burrow and retirement time relative to sunrise were similar for both sexes. Young deer mice emerged significantly later, made more trips of shorter duration, spent less total time outside, and retired to their burrow earlier than adults. Reproductive females emerged later, made fewer trips of generally longer duration, and spent shorter total amounts of time away from the burrow each night than non-reproductive females. Return visits of reproductive females were of longer duration than non-reproductives, but total time spent inside and time of retirement for the night did not differ relative to reproductive status. From parturition through lactation, activity of females showed a number of directional trends. Results suggest that under natural conditions, activity patterns of deer mice are highly variable but responsive to both the changing physical environment and internal conditions related to sex-specific maximization of fitness.

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