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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.
301

Masterkey RFID

Björklund, Simon January 2024 (has links)
This report presents the design of a conceptual prototype aimed at identifying keys in specific positions inside a cabinet utilizing Radio-frequency identification (RFID)technology. The prototype integrates RFID readers, managed by a microcontroller unit(MCU), establishing a backend peripheral system. The cabinet is made of steel, and given RFID’s sensitivity to nearby metal, experimentation was conducted to evaluate the impact of metal proximity on the reading range. Experimental results reveal a reduction in the reading range of 15 mm (43%) by one metal sheet and 26 mm (74%) by two metal sheets present, highlighting the relation between RFID technology and metallic environments. Additionally, the finished prototype is also presented in the Results and Discussion section, giving a more detailed insight into its practical implementation. This project demonstrates the viability of item-level identification through the utilization of low-frequency readers. Particularly relevant for positional identification, the short reading range of a low-frequency reader offers precision by limiting the area in which a detected transponder may be located. / Denna rapport presenterar designen av en konceptuell prototyp avsedd att identifiera nycklar på specifika positioner i ett skåp med användning av Radio-frequency identification (RFID) teknologi. Prototypen integrerar RFID läsare, hanterade av en microcontroller unit (MCU), och etablerar ett perifert backendsystem. Skåpet är gjort av stål, och givet RFIDs känslighet mot nära metal har experiment utförts för att utvärdera hur metallen påverkar en läsares omfång. Experimentella resultat avslöjar en reduktion i läsarens omfång på 15 mm (43%) med en metallplatta och 26 mm (74%) med tvåmetallplattor närvarande. Dessutom presenteras den färdiga prototypen i Resultat och Diskussionsdelen, för att ge en mer detaljerad insyn på dess praktiska implementation. Detta projektet demonstrerar genomförbarheten av identifikation på artikelnivå genomanvändandet av lågfrekvens läsare. Särskilt relevant för positionell identifikation är det korta omfånget av en lågfrekvens läsare, då detta erbjuder precision genom att begränsaområdet där en transponder kan lokaliseras.
302

Studies on enzymes and reaction conditions in recombinase polymerase amplification / リコンビナーゼポリメラーゼ増幅法の酵素と反応条件に関する研究

Kevin, Maafu Juma 25 March 2024 (has links)
京都大学 / 新制・課程博士 / 博士(農学) / 甲第25357号 / 農博第2623号 / 新制||農||1109(附属図書館) / 学位論文||R6||N5529 / DFAM / 京都大学大学院農学研究科食品生物科学専攻 / (主査)教授 保川 清, 教授 井上 和生, 教授 谷 史人 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DFAM
303

Evaluation eines Schulinterventionsprojekts zur Steigerung des Obst- und Gemüsekonsums bei Kindern in niedersächsischen Grundschulen / Evaluation of a school-based intervention to increase the fruit and vegetable intake of primary school children in Lower Saxony

Mittmann, Silke 12 November 2015 (has links)
Kinder und Jugendliche in Deutschland essen laut der bundesweiten KiGGS-Untersuchung weniger Obst und Gemüse als von den Fachgesellschaften empfohlen. Ein höherer Verzehr geht mit einem geringeren Risiko für ernährungsassoziierte Erkrankungen wie Krebs, Herz-Kreislauf-Erkrankungen, Übergewicht/Adipositas oder Bluthochdruck einher. Basierend auf der Kampagne „5-a-day“, wurde von der Deutschen Krebsgesellschaft das Projekt „5 am Tag für Kids“ für 3. und 4. Klassen als Maßnahme der Verhaltensprävention entwickelt. Ziel der Intervention war die Steigerung des Obst- und Gemüsekonsums bei den Kindern. Mit Hilfe einer prä-post Befragung von 1.376 Schülern, deren Eltern und 69 Lehrkräften von 35 niedersächsischen Grundschulen, wurde das Konzept evaluiert. Die Akzeptanz und Bewertung durch Schüler und Lehrer war hoch, eine nachhaltige Steigerung des Obst- und Gemüseverzehrs konnte jedoch nicht festgestellt werden. Um weitere Erkenntnisse darüber zu gewinnen, welche Bausteine schulischer Interventionen erfolgsversprechend sind, sind auch Ergebnisse der Befragung zum Projekt „Entdeckungsreise Essen“ in die Dissertation eingeflossen. Dieser praktisch orientierte, partizipative und explorative Ansatz richtet sich an 5. und 6. Klassen. Erste Ergebnisse scheinen vielversprechend, dass die Schüler die Lerninhalte auch auf ihr Lebensumfeld übertragen haben, indem Sie häufiger neue Lebensmittel probierten und zu Hause selbst Rezepte nachkochten. Insgesamt existiert nach wie vor großer Handlungsbedarf hinsichtlich der Konzeptionierung und flächenweiten Implementierung erfolgsversprechender verhaltens- und verhältnispräventiver Maßnahmen zur Förderung des Obst- und Gemüsekonsums bzw. eines gesunden Ernährungsverhaltens in geeigneten Settings wie Kindertageseinrichtungen und Schulen. In Kombination mit einer gesteigerten Inanspruchnahme von Früherkennungsuntersuchungen könnten so die persönlichen, gesellschaftlichen und wirtschaftlichen Belastungen, die aus chronischen Erkrankungen resultieren, reduziert werden.
304

A generic architecture for semantic enhanced tagging systems

Magableh, Murad January 2011 (has links)
The Social Web, or Web 2.0, has recently gained popularity because of its low cost and ease of use. Social tagging sites (e.g. Flickr and YouTube) offer new principles for end-users to publish and classify their content (data). Tagging systems contain free-keywords (tags) generated by end-users to annotate and categorise data. Lack of semantics is the main drawback in social tagging due to the use of unstructured vocabulary. Therefore, tagging systems suffer from shortcomings such as low precision, lack of collocation, synonymy, multilinguality, and use of shorthands. Consequently, relevant contents are not visible, and thus not retrievable while searching in tag-based systems. On the other hand, the Semantic Web, so-called Web 3.0, provides a rich semantic infrastructure. Ontologies are the key enabling technology for the Semantic Web. Ontologies can be integrated with the Social Web to overcome the lack of semantics in tagging systems. In the work presented in this thesis, we build an architecture to address a number of tagging systems drawbacks. In particular, we make use of the controlled vocabularies presented by ontologies to improve the information retrieval in tag-based systems. Based on the tags provided by the end-users, we introduce the idea of adding “system tags” from semantic, as well as social, resources. The “system tags” are comprehensive and wide-ranging in comparison with the limited “user tags”. The system tags are used to fill the gap between the user tags and the search terms used for searching in the tag-based systems. We restricted the scope of our work to tackle the following tagging systems shortcomings: - The lack of semantic relations between user tags and search terms (e.g. synonymy, hypernymy), - The lack of translation mediums between user tags and search terms (multilinguality), - The lack of context to define the emergent shorthand writing user tags. To address the first shortcoming, we use the WordNet ontology as a semantic lingual resource from where system tags are extracted. For the second shortcoming, we use the MultiWordNet ontology to recognise the cross-languages linkages between different languages. Finally, to address the third shortcoming, we use tag clusters that are obtained from the Social Web to create a context for defining the meaning of shorthand writing tags. A prototype for our architecture was implemented. In the prototype system, we built our own database to host videos that we imported from real tag-based system (YouTube). The user tags associated with these videos were also imported and stored in the database. For each user tag, our algorithm adds a number of system tags that came from either semantic ontologies (WordNet or MultiWordNet), or from tag clusters that are imported from the Flickr website. Therefore, each system tag added to annotate the imported videos has a relationship with one of the user tags on that video. The relationship might be one of the following: synonymy, hypernymy, similar term, related term, translation, or clustering relation. To evaluate the suitability of our proposed system tags, we developed an online environment where participants submit search terms and retrieve two groups of videos to be evaluated. Each group is produced from one distinct type of tags; user tags or system tags. The videos in the two groups are produced from the same database and are evaluated by the same participants in order to have a consistent and reliable evaluation. Since the user tags are used nowadays for searching the real tag-based systems, we consider its efficiency as a criterion (reference) to which we compare the efficiency of the new system tags. In order to compare the relevancy between the search terms and each group of retrieved videos, we carried out a statistical approach. According to Wilcoxon Signed-Rank test, there was no significant difference between using either system tags or user tags. The findings revealed that the use of the system tags in the search is as efficient as the use of the user tags; both types of tags produce different results, but at the same level of relevance to the submitted search terms.
305

Assessment of Retroviruses as Potential Vectors for the Cell Delivery of Prions

Rahimi Khameneh, Shabnam 31 October 2012 (has links)
Transmissible spongiform encephalopathies (TSEs) or prion diseases are a class of fatal brain disorders better known as Creutzfeldt-Jacob Disease (CJD) in humans, bovine spongiform encephalopathy (BSE) in cattle, scrapie in sheep, and chronic wasting disease (CWD) in deer and elk. The infectious agent responsible for these diseases is a misfolded prion protein capable of catalyzing a conformational change in normal cellular prion proteins (PrPC) into aberrant disease-causing structural isoforms (PrPSc). Although the etiological agent for TSEs has clearly been defined as PrPSc, there are important gaps in our understanding of how these proteins target and invade brain tissue. It remains to be established how ingested PrPSc ultimately reach the brain and also to understand why these tissues are particularly targeted, notwithstanding that several other tissues highly express prion proteins. Certain viruses, retroviruses in particular, efficiently hijack host proteins and can carry these proteins with them when they are released from a cell. Several lines of evidence have shown that prions and retroviruses can interact and associate at various stages of the retroviral replication cycle. Of special interest is that most retroviruses can cross the blood-brain barrier and could therefore deliver host-derived proteins to neuronal cells. In view of these observations, this thesis investigates whether retroviruses can act as vectors to capture prions from an infected cell and deliver them to a susceptible target cell. In this work, I have cloned human and mouse prion cDNAs from PBMCs and the murine cell line NIH 3T3. Either a FLAG epitope tag or the eGFP reporter protein cDNA was inserted into a region of the prion cDNA that is predicted to be amenable to such genetic insertions without affecting protein folding or expression. I then confirmed using both fluorescent and confocal microscopy and that the recombinant proteins had a similar cell distribution to the endogenous prion protein. Using Western blot analysis, I then showed that endogenous and overexpressed prion proteins can be detected in co-transfected cells producing HIV and murine leukemia virus (MLV) retroviral particles. Finally, I went on to show that prions are also present at high levels in HIV and MLV retroviral particles released from these cells. This work constitutes the first step in determining whether retroviruses can act as vectors for prion dissemination. Establishing a strong and clear association between retroviruses, pathogenic prions and prion disease would provide the rationale for preventive measures to be taken directly against retroviruses in order to protect humans and animals that have been newly exposed to PrPSc-infected products or those who are genetically predisposed to develop prion diseases. Anti-retroviral drugs could also be potentially used to delay disease progression and reduce prion transmission in human and animal tissues. The availability of such a treatment would constitute a significant advancement because there is currently no cure or treatment for prion diseases.
306

Comparative Mapping of QTLs Affecting Oil Content, Oil Composition, and other Agronomically Important Traits in Oat (Avena sativa L.)

Hizbai, Biniam T. 01 November 2012 (has links)
Groat oil content and composition are important quality traits in oats (Avena sativa L). These traits are controlled by many genes with additive effects. The chromosomal regions containing these genes, known as quantitative trait loci (QTL), can be discovered through their close association with markers. This study investigated total oil content and fatty acid components in an oat breeding population derived from a cross between high oil ('Dal') and low oil ('Exeter') parents. A genetic map consisting of 475 DArT (Diversity Array Technology) markers spanning 1271.8 cM across 40 linkage groups was constructed. QTL analysis for groat oil content and composition was conducted using grain samples grown at Aberdeen, ID in 1997. QTL analysis for multiple agronomic traits was also conducted using data collected from hill plots and field plots in Ottawa, ON in 2010. QTLs for oil content, palmitic acid (16:0), stearic acid (18:0), oleic acid (18:1), linoleic acid (18:2) and linolenic acid (18:3) were identified. Two of the QTLs associated with oil content were also associated with all of the fatty acids examined in this study, and most oil-related QTL showed similar patterns of effect on the fatty acid profile. These results suggest the presence of pleiotropic effects on oil-related traits through influences at specific nodes of the oil synthesis pathway. In addition, 12 QTL-associated markers (likely representing nine unique regions) were associated with plant height, heading date, lodging, and protein content. The results of this study will provide information for molecular breeding as well as insight into the genetic mechanisms controlling oil biosynthesis in oat.
307

Peptide targeting by spontaneous isopeptide bond formation

Zakeri, Bijan January 2011 (has links)
Peptide fusion tags are fundamental for the identification, detection, and capture of proteins in biological assays. Commonly used peptide fusion tags rely on temporary non-covalent interactions for binding, which can put constraints on assay sensitivity. Here, peptide fusion tags were developed that could specifically interact with protein binding partners via spontaneous and irreversible isopeptide bond formation. To develop covalently interacting peptide-protein pairs, outer-membrane proteins from Gram-positive bacteria that form autocatalyzed intramolecular isopeptide bonds were dissected to generate a short peptide fragment and a protein binding partner. Initially, the major pilin subunit Spy0128 from Streptococcus pyogenes was split to develop the 16 residue isopeptag peptide and the 31 kDa pilin-C protein partner. The isopeptag:pilin-C pair were able to react via spontaneous isopeptide bond formation between an Asn residue in isopeptag and a Lys residue in pilin-C without the requirement for any accessory factors, and with a yield of 60% after a 72 hr reaction. Reconstitution between the isopeptag:pilin-C pair was robust and occurred under all biologically relevant conditions tested, and also in the complex environment of a bacterial cytosol and on the surface of mammalian cells. A similar approach was also used to dissect the small CnaB2 domain that is part of the large FbaB fibronectin-binding protein from S. pyogenes. This led to the development of a more efficient peptide-protein pair, which was rationally modified to generate the highly optimized SpyTag:SpyCatcher pair. SpyTag is a 13 amino acid peptide with a reactive Asp that forms a spontaneous intermolecular isopeptide bond with a Lys present in the 12 kDa SpyCatcher binding partner. In a reaction with SpyTag, over 40% of SpyCatcher was depleted after 1 min and SpyCatcher could no longer be detected after 2 hr. The SpyTag and SpyCatcher reaction did not require any accessory factors and proceeded efficiently at a range of biologically relevant temperatures, pH values, concentrations, buffer compositions, and in the presence of commonly used detergents. The SpyTag:SpyCatcher technology was also used for specific cell surface labelling on mammalian cell membranes. SpyTag and SpyCatcher are both composed of the regular 20 amino acids and can therefore be genetically encoded as fusion constructs for a variety of in vitro and in vivo applications. Potential applications of the SpyTag:SpyCatcher technology include specific cell surface labelling, the development of novel protein architectures, and the covalent and irreversible capture of target proteins in biological assays.
308

Génomique fonctionnelle de la transduction de signal, isolement et caractérisation de récepteurs kinases chez Solanum chacoense

Germain, Hugo January 2007 (has links)
Thèse numérisée par la Direction des bibliothèques de l'Université de Montréal.
309

Detection and identification of elliptical structure arrangements in images : theory and algorithms / Détection et identification de structures elliptiques en images : Paradigme et algorithmes

Patraucean, Viorica 19 January 2012 (has links)
Cette thèse porte sur différentes problématiques liées à la détection, l'ajustement et l'identification de structures elliptiques en images. Nous plaçons la détection de primitives géométriques dans le cadre statistique des méthodes a contrario afin d'obtenir un détecteur de segments de droites et d'arcs circulaires/elliptiques sans paramètres et capable de contrôler le nombre de fausses détections. Pour améliorer la précision des primitives détectées, une technique analytique simple d'ajustement de coniques est proposée ; elle combine la distance algébrique et l'orientation du gradient. L'identification d'une configuration de cercles coplanaires en images par une signature discriminante demande normalement la rectification Euclidienne du plan contenant les cercles. Nous proposons une technique efficace de calcul de la signature qui s'affranchit de l'étape de rectification ; elle est fondée exclusivement sur des propriétés invariantes du plan projectif, devenant elle même projectivement invariante / This thesis deals with different aspects concerning the detection, fitting, and identification of elliptical features in digital images. We put the geometric feature detection in the a contrario statistical framework in order to obtain a combined parameter-free line segment, circular/elliptical arc detector, which controls the number of false detections. To improve the accuracy of the detected features, especially in cases of occluded circles/ellipses, a simple closed-form technique for conic fitting is introduced, which merges efficiently the algebraic distance with the gradient orientation. Identifying a configuration of coplanar circles in images through a discriminant signature usually requires the Euclidean reconstruction of the plane containing the circles. We propose an efficient signature computation method that bypasses the Euclidean reconstruction; it relies exclusively on invariant properties of the projective plane, being thus itself invariant under perspective
310

Určení kinetických parametrů pro enzymovou reakci katalyzovanou histidinkinasou s globinovou strukturou senzorové domény / The kinetic analysis of the enzyme reaction catalyzed by the globine coupled histidine kinase

Fojtíková, Veronika January 2014 (has links)
Two-component signal systems serve as basic stimulus-response coupling mechanism to allow organisms (predominantly bacteria) to sense and respond to changes in many environmental conditions. The prototypical system consists of two proteins, namely a histidine kinase, containing a sensor domain and catalytic kinase core, and a response regulator protein (RR protein). Extracellular stimuli are sensed by a histidine kinase sensor domain. Then ATP is bound to the catalytic kinase core and the γ-phosphoryl group is transferred to the conserved histidine residue. This phosphoryl group is subsequently transferred to a conserved aspartate residue within the RR protein. Phosphotransfer to the RR protein results in activation of a downstream effector domain that elicits the specific response (usually it is transcription activity, but a few RR proteins function as enzymes). The histidine kinase sensor domain is designed for specific ligand interactions. This master thesis focused on the unique histidine kinase containing a sensor domain with a globine structure, which coordinates a heme molecule, namely globin-coupled histidine kinase from Anaeromyxobacter sp. Fw 109-5 (AfGcHK) and its appropriate RR protein. The aim of this thesis was to study and characterize the phosphorylation activity of AfGcHK and RR...

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