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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.
71

The Development of Phonation-type Contrasts in Plosives: Cross-linguistic Perspectives

Kong, Eun Jong 10 September 2009 (has links)
No description available.
72

Cost Effective Rollover Mitigation Strategy

Schneider, Shawn Patrick 27 April 2010 (has links)
A cost effective method of rollover mitigation in vehicles is presented. The method was designed so that some of the system states were measured by sensors that are already available on most vehicles and so that other states could be measured with relatively low cost sensors. Also, the control algorithm was designed to be implementable using a series of look up tables and computationally efficient equations to enable the use of low-cost controller platforms. These look up tables and equations can be modified to change the conservativeness of the method as well as to configure the method for use on almost any 4-wheeled vehicle. Lastly, the proposed mitigation technique was designed to be directly implementable with existing vehicle hardware. To develop this method, a vehicle model was created using several advanced computer packages including SolidWorks 2008™, MATLAB ®, Simulink®, and SimMechanics™. Once created, the model was outfitted with virtual sensors that represent data from realistic sensor types. A detection algorithm was designed around the hypothesis of a stability boundary utilizing the sensor data to detect impending rollover. Finally, a mitigation algorithm was designed to limit throttle and braking upon impending rollover. This algorithm was defined using the basic principles of end-stop control, but was adapted to work appropriately with this scenario. To conclude this research, two simple maneuvers were used to verify the effectiveness of this system to mitigate vehicle rollover. This research was government sponsored and in some instances utilized secured data. Due to the nature of this material, some data has been omitted from this document. / Master of Science
73

Abdominal Aortic Aneurysm : Aspects on how to affect mortality from rupture

Hager, Jakob January 2014 (has links)
Abdominal Aortic Aneurysm (AAA) is a disease that mainly affects elderly men, and ruptured AAA (rAAA) is associated with a mortality of > 80%. AAA seldom gives any symptoms prior to rupture. The aims of this thesis were to investigate different aspects of how to affect mortality from rAAA. In Study I, we identified 849 patients treated for rAAA during 1987-2004, and studied the 30-day survival after surgery, depending on whether they came directly to the treating hospital (one-stop) or were transferred via another hospital (two-stop). A two-stop referral pattern resulted in a 27% lower population-based survival rate for patients 65-74 years of age. However, the consequences would be small even if a one-stop referral pattern could be generally accomplished, due to the huge over-all mortality related to rAAA, hence an argument to find and treat AAA before rupture, e.g. by screening. In Study II, we examined the AAA-prevalence and the risk factors for AAA among 70-year-old men. The screening-detected AAA-prevalence was 2.3%, thus less than half the predicted. The most important risk factor was smoking. In Study III, we compared the screening-detected AAA-prevalence, the attendance rate, and the rate of opportunistic detection of AAA, between almost 8000 65- and 6000 70-year-old men. There was no difference in the screening-detected prevalence; probably due to the fact that almost 40% of the AAAs among the 70-year-old were already known prior to screening, compared to roughly 25% in the 65-year-old. The attendance rate was higher among the 65-year-old men, 85.7% compared 84.0% in the 70-year-old. Thus, there is no benefit of screening for AAA among 70- instead of 65-year-old men. In Study IV, a cost-effectiveness analysis, we found that screening for AAA still appears to be cost-effective, despite profound changes in disease pattern and AAA-management. In conclusion, we found that mortality from rAAA is not affected in any substantial way by different referral patterns and hence centralisation of services for AAA/rAAA is not a solution. A better alternative is to prevent rupture through early detection by screening. Screening 65-year-old men for AAA still appears to be cost-effective, despite profound changes in disease pattern and AAA-management during the last decade. Screening 70- instead of 65-year-old men will not increase the efficacy of screening.
74

Vulnérabilité à la schizophrénie : approche préclinique chez la souris porteuse d’une altération du gène codant la protéine STOP / From vulnerability to schizophrenia : preclinical approach in mice with an alteration of the gene coding for STOP protein

Volle, Julien 27 May 2010 (has links)
Au cours de ce travail, nous avons utilisé des souris ayant une délétion totale (KO) ou partielle (hétérozygotes) du gène codant la protéine STOP. La souris KO STOP constitue un modèle reconnu pour l’étude de la physiopathologie de la schizophrénie (SCH). Ce travail a permis d’étendre les données disponibles en mettant en évidence chez la souris KO STOP des troubles comportementaux qui miment les symptômes apparentés à l’ensemble des dimensions de la SCH. La comparaison des déficits chez des souris KO STOP générées à partir de différentes souches a permis de montrer que la délétion du gène STOP induit un phénotype robuste. De plus, notre travail permet de suggérer que, de par leur construction et leur phénotype, la souris hétérozygote STOP évoque la vulnérabilité à la SCH et pourrait constituer un modèle animal pertinent pour étudier les facteurs qui, interagissant avec une vulnérabilité génétique, favoriserait la décompensation psychotique. Dans cette optique, nous avons étudié l’influence de différents types de stress chroniques appliqués à différents moments clés du développement sur le phénotype de nos modèles animaux. Aucun des stress utilisés (isolement, stress chronique multiple, privation maternelle) n’a modifié le phénotype des souris hétérozygotes STOP à l’âge adulte, ni dans le sens de l’émergence ni dans celui d’une aggravation de troubles apparentés à la symptomatologie de la SCH. Ces résultats posent la question du type de stress, de son intensité et de la fenêtre temporelle où il doit être appliqué qui, associé à une altération génique donnée, validerait le modèle physiopathologique actuel basé sur une interaction délétère entre vulnérabilité et stress / In this work, we used mice with total (STOP null) or partial deletion (heterozygous) for the gene encoding the STOP protein. STOP null mice represent a recognized model for studying the physiopathology of schizophrenia (SCH). This work allowed us to extend the available phenotype by showing that STOP null mice exhibit various behavioural impairments mimicking symptoms corresponding to all SCH dimensions. By comparing the alterations present in STOP null mice generated from various strains, we showed that the STOP deletion induces a robust phenotype linked to SCH. In addition, through their construct and phenotype validity, the present work allows us to suggest that the STOP heterozygous mice evoke SCH vulnerability and could be a relevant model for studying the parameters which could favour SCH when interacting with a genetic vulnerability. In this context, the effects of chronic stress applied at different key steps of the mouse development were studied on the phenotype of our animal models. Any stress paradigm used (short-term isolation, chronic multiple stress, maternal deprivation) has been not able to alter the phenotype of STOP heterozygous mice measured in adulthood, neither by inducing nor by worsening alterations linked to SCH. According to the current SCH physiopathology hypothesis based on a deleterious interaction between susceptibility to SCH and stress, our findings raise the question regarding the type of stress paradigm, including stress intensity and the time window where it is applied, that could induce frank psychosis when interacting with a specific genetic alteration
75

Den levande soptunnan : designfiktion, rörlig bild och återvinning

Meinoryte, Viktorija January 2017 (has links)
Det här kandidatarbetet handlar om rörlig bild med miljöförstöring som tema och hur designfiktion tillsammans med berättande kan användas för att skapa rörlig bild. För att undersöka hur berättande och val av gestaltningsmetod påverkar budskap har olika produktioner inom rörlig bild diskuterats. Utifrån undersökningen har designfiktion och stopmotion gjorts som metodval i skapandet av gestaltningen. Som resultat diskuteras designfiktion som designmetod för skapande av framtida världar med miljöförstöring som tema samt berättandets påverkan av budskap. / This bachelor’s thesis is about motion pictures with pollution as a theme and how designfiction together with narrative can be used to create motion pictures. To research how narrative and choice of designmethod affects silent messages, a research about other motion graphics has been discussed. Based on the research, design fiction and stop motion has been choosen as a method of creating design. As result of the thesis, design fiction is discussed as a design method for the creation of future worlds with pollution as a theme and the narrative's influence on silent messages.
76

Fidélité de la terminaison de la traduction chez les eucaryotes / Translation termination accuracy in eukaryotes

Blanchet, Sandra 18 September 2014 (has links)
La terminaison de la traduction se produit lorsqu’un codon stop entre au site A du ribosome où il est reconnu par le facteur de terminaison eRF1 accompagné du facteur eRF3. Cette étape de la traduction est encore mal comprise chez les eucaryotes. Au cours de ma thèse je me suis intéressée à l’étude de la fidélité de la terminaison de la traduction afin de mieux comprendre et caractériser les mécanismes moléculaires mis en jeu lors du décodage du codon stop.L’un de mes projets consistait à mieux caractériser une région du domaine N-terminal d’eRF1, la cavité P1, identifiée comme étant impliquée dans l’efficacité de terminaison. Grâce à une quantification de l’efficacité de translecture de mutants de la cavité P1, j’ai pu mettre en évidence le rôle de résidus clés comme les serines 33 et 70, impliquées dans le décodage spécifique du codon UGA probablement via une interaction directe entre les deux résidus, ou encore l’arginine 65 et la lysine 109, essentielles pour une terminaison efficace sur les trois codons stop. L’analyse par RMN de ces mutants a également permis de montrer que ces résidus étaient importants pour la conformation correcte de la cavité et potentiellement impliqués dans une interaction directe avec l’ARNm. La combinaison des données génétiques et structurales nous a permis de proposer un modèle d’interaction entre l’ARNm et le facteur de terminaison eRF1 dans lequel le codon stop serait reconnu en partie par l’intermédiaire de la cavité P1. Dans la cellule, la terminaison est toujours en compétition avec la translecture, qui correspond à l’incorporation d’un ARNt proche-cognat au niveau du codon stop. Afin d’identifier les acides aminés incorporés par translecture au niveau du codon stop, j’ai mis au point un système basé sur l’expression et la purification de protéines issues de la translecture qui sont ensuite analysées par spectrométrie de masse. J’ai pu mettre en évidence que la glutamine, la tyrosine et la lysine s’incorporent au niveau des codons UAA et UAG, alors que le tryptophane, la cystéine et l’arginine sont retrouvés au niveau du codon UGA. J’ai également pu montrer que le contexte en 5’ n’influençait pas l’incorporation des acides aminés au codon stop mais qu’en revanche, la présence de la paromomycine avait un impact sur la sélection des ARNt suppresseurs naturels. Ce projet permet d’apporter de nouvelles informations sur les règles de décodage grâce à l’analyse des appariements entre codons stop et anticodons des ARNt naturels suppresseurs. Il permet également d’envisager des perspectives thérapeutiques dans le cadre des maladies liées à la présence d’un codon stop prématuré et pour lesquelles le traitement repose sur l’utilisation de la translecture afin de ré-exprimer des protéines entières. / Translation termination occurs when a stop codon enters the A site of the ribosome where it is recognized by eRF1 (eukaryotic release factor 1), associated with eRF3. This step of translation is not yet understood in eukaryotes. During my PhD, I was interested in studying translation termination accuracy to better understand and characterize the molecular mechanisms involved in stop codon decoding.One of my project consisted in characterizing a region in eRF1 N-terminal domain, pocket P1, identified to be involved in termination efficiency. Through a quantification of readthrough efficiency of pocket P1 mutants, I have highlighted the role of key residues, like serine 33 and serine 70, implicated in specific recognition of UGA stop codon, probably through a direct interaction between the two amino acids, and also arginine 65 and lysine 109, essential for efficient termination on the three stop codons. The analysis of the mutants by NMR revealed that these residues are also important for proper conformation of the cavity and potentially involved in a direct interaction with mRNA. The combination of our genetic data and structural analysis allowed us to propose a model of interaction between termination factor eRF1 and the mRNA, in which the stop codon would be recognized partially through pocket P1.In cells, termination always competes with readthrough which corresponds to the incorporation of near-cognate tRNAs at the stop codon. To identify the amino acids inserted by readthrough at the stop codon, I have developed a reporter system based on the expression and purification of readthrough proteins that are analyzed by mass spectrometry. I found that glutamine, tyrosine and lysine are inserted at UAA and UAG stop codons, whereas tryptophan, cysteine and arginine are inserted at UGA stop codon. I also showed that the 5’ nucleotide context does not influence the incorporation of amino acids at the stop codons by readthrough, but that, in contrast, the presence of paromomycin impacted the selection of natural suppressors tRNAs incorporated by readthrough. This project gives us new insights into the decoding rules by analyzing the base pairings between stop codon and near-cognates anticodons. It also allows us to consider therapeutic prospects for the treatment of premature stop codon diseases which uses readthrough as a tool to re-express full-length proteins from mRNAs that are interrupted by the presence of a premature stop codon.
77

消費者多重行為與商業土地使用關係之研究

曾菁敏, Zeng, Jing Min Unknown Date (has links)
商業區內商店聚集分佈,使消費者可基於本身的多重目的(multi-purpose)、活動近便性、商品多樣性等因素,以連續至多重地點(multi-stop)之不同類型商店從事有關消費或休閒等活動。而一商業區內之消費者其至不同類型商店間之活動關連程度為何?消費者活動型態與商店空間分佈是否具互動關係,及不同商業階層之消費者活動型態是否有差異?則為本研究目的所在。 本研究所謂消費者多重行為係指一商業區內之消費者,從一家商店再至另一家商店之活動型態而言。而此活動型態則包括消費者至不同類型商店之多重地點(multi-stop)與多重目的(multi-purpose)之關係。研究結果顯示: 1、就消費者活動特性而言:忠孝東路四段及公館之商業區,消費者活動型態以多重行為(multi-stop & multi-purpose)為主。相對地,兩商業區內之消費者僅至一家商店之單一行為(single-purpose & single-stop)的比例則顯偏低。 2、就商店空間分佈而言:忠孝東路四段之商業區,以百貨服飾日用品店、餐飲店(本研究所做之定義)等之聚集分佈為主。而公館之商業區,則以服飾日用品店、餐飲店(本研究所做之定義)等之聚集分佈為主。 3、就消費者活動特性與商店空間分佈之關係而言: (1)忠孝東路四段之商業區:消費者從百貨服飾日用品店再至相同類型百貨服飾日用品店之活動關連程度最強。其次係從百貨服飾日用品店再至餐飲店及從餐飲店再至百貨服飾日用品店等活動型態。故消費者活動型態以百貨服飾日用品店與餐飲店等類為主,而此類型商店在空間分佈上亦相當聚集。 (2)公館之商業區:消費者從餐飲店再至服飾日用品店之活動關連程度最強。其次為從服飾日用品店再至餐飲店及服飾日用品店再至服飾日用品店等活動型態。故消費者活動型態以餐飲店與服飾日用品店等類型為主,而此類型商店在空間分佈上之聚集現象明顯。 故本研究獲一重要結論是,一商業區內之消費者活動關連程度較強的商店類型,該類型商店在空間分佈上亦呈現聚集象。
78

Určení základního tvaru slova / Determination of basic form of words

Šanda, Pavel January 2011 (has links)
Lemmatization is an important preprocessing step for many applications of text mining. Lemmatization process is similar to the stemming process, with the difference that determines not only the word stem, but it´s trying to determines the basic form of the word using the methods Brute Force and Suffix Stripping. The main aim of this paper is to present methods for algorithmic improvements Czech lemmatization. The created training set of data are content of this paper and can be freely used for student and academic works dealing with similar problematics.
79

Suppression traductionnelle des codons stop chez les mammifères / Translational suppression of stop codons in mammals

Bugaud, Olivier 21 September 2016 (has links)
Entre 10% et 30% des maladies humaines sont liées à l'apparition d'une mutation non-sens (PTC). La synthèse protéique est alors arrêté prématurément. Cet arrêt peut être inhibé par des molécules inductrices de translecture qui permettent l’incorporation d’un ARNt suppresseur naturel au niveau du PTC (translecture). Le ribosome peut alors franchir le PTC et restaurer l’expression de la protéine.Au cours de ma thèse, je me suis intéressé à la suppression des codons stop en caractérisant de nouvelles molécules inductrices de translecture et en analysant les mécanismes de la fidélité de la traduction.J’ai tout d’abord mis au point un système de criblage innovant avec lequel j’ai testé plus de 17 000 molécules et identifié la molécule TLN468. J’ai pu mettre en évidence que cette molécule est capable d’induire la réexpression d’une protéine p53 active.J'ai aussi caractérisé de nouveaux composés dérivés d’aminoglycosides. J’ai pu montré que le NB124 est capable d’induire l’apoptose de cellules tumorales via la réexpression de la protéine p53 tout ayant une toxicité bien plus faible que la gentamicine.En parallèle, j’ai développé une approche en molécule unique permettant d’étudier les erreurs programmées du ribosome (recodage). J’ai ainsi pu analyser la cinétique d’élongation des ribosomes eucaryotes et montré que l’initiation de la traduction sur un site d’entrée interne (IRES) ralentit le ribosome lors des premiers cycles d’élongation. / Nonsense mutations, also known as premature termination codons (PTCs) are responsible for 10% to 30% of all human genetic diseases. Nonsense translation suppression can be induced by readthrough inducers. The presence of such PTC leads to premature translation termination. These stop therapeutic strategies have emerged which attempt to use molecules that facilitate tRNA incorporation at the PTC (readthrough). The, translation continue in the same reading frame until the next stop codon. I first developed an innovative screening system I used to test more than 17,000 molecules and have identified one hit, TLN468 molecule. I have shown that this molecule is able to induce re-expression of an active p53 protein.I also characterized new compounds derived from aminoglycosides. I have shown that the NB124 induces apoptosis of tumor cells by re-expressing p53 protein while having a much lower toxicity than gentamicin.I developed a single molecule approach for studying the ribosome programmed errors (recoding). I was able to analyze the kinetics of elongation eukaryotic ribosomes and showed that the initiation of translation at an internal entry site (IRES) slows the ribosome during the first elongation cycle.
80

Realisation and evaluation of a start-stop journal bearing test-rig / Realisering och utvärdering av en glidlagerrigg för start-stop-provning

Gralde, Marcus, Sölvason, Tómas Rúnar January 2014 (has links)
While there has been substantial body of work in the field of journal bearing research, much of it is today theoretical or simulated due to today’s computing power. Scania produces experimental data from motor testing, but these are expensive and time consuming. Furthermore there is a difficulty in keeping a sufficiently controlled environment, which at times makes it hard to draw conclusions from testing results. They therefore wish to develop a test-rig which can evaluate friction and wear in journal bearings. This thesis is a continuation of a project in the course Advanced Machine Design given at KTH Royal Institute of Technology. During this thesis the test-rig has been manufactured, built, and evaluated. Furthermore software for the test-rig was developed. Information on journal bearings, risk assessment and signal noise handling were sought. Mechanical development was done with Autodesk Inventor, while Matlab was used for software development. Factorial design was utilised when designing tests and compared to a simple theoretical model. Test results showed promising results for Stribeck curve-producing tests, with good resemblance to known frictional values and trends. Furthermore the test-rig showed good repeatability for replicated tests and produced wear on the bearing shells used. During a prolonged test, the shaft and support-bearings were damaged and requires servicing to be in an operational state. The test-rig requires to be further verified, but the tests that were carried out showed valuable and reliable information on wear and frictional values. Keywords: journal bearing, hydrodynamic lubrication, wear, start-stop, test-rig / Även om en betydande mängd forskning inom glidlager och fullfilmslager har genomförts så är med dagens datorkapacitet en stor del av resultaten numera teoretiska eller simulerade. Medan Scania producerar experimentella resultat, så är dessa dyra och tidskrävande. Vidare är det ibland svårt att hålla en tillräckligt kontrollerad miljö för att dra slutsatser från proverna. Med en dedikerad testrigg som kan tillförlitliga resultat tas fram billigare och snabbare. Detta examensarbete är en fortsättning av kursen Avancerad Maskinkonstruktion som ges vid Kungliga Tekniska Högskolan. Under detta examensarbete har testriggen tillverkats, byggts och utvärderats. Vidare har programvara för testriggen utvecklats. Informationssökning gjordes på glidlager, fullfilmslager, riskbedömning och signalbrushantering. Mekanisk utveckling har gjorts i Autodesk Inventor, medan Matlab användes för mjukvaruutveckling. Faktorial design har nyttjats vid utformningen av tester. Resultaten jämfördes med en enkel teoretisk modell. Testresultaten visade lovade resultat för Stribeck kurva-producerande tester, med god likhet till kända friktionsvärden och trender. Testriggen visade god reproducerbarhet vid replikerade tester. Testriggen producerar slitage på samtliga testade lagerytor. Under ett längre test så har axel och stödlager skadats, varför service behövs för att testriggen skall vara i brukbart skick. Testriggen kräver ytterligare verifiering, men resultaten från de prov som genomförts visar att test-riggen ger värdefull och tillförlitlig information om slitage och friktion kunna utrönas. Nyckelord: glidlager, hydrodynamisk smörjfilm, nötning, start-stop, testrigg

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