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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.
431

Caractérisation Structurale et Fonctionnelle de deux Enzymes de la Famille des Aldéhyde déshydrogénases

Moniot, Sébastien Corbier, Catherine. Didierjean, Claude. January 2008 (has links) (PDF)
Thèse de doctorat : Enzymologie Moléculaire et Biologie Structurale : Nancy 1 : 2008. / Titre provenant de l'écran-titre.
432

Molecular mechanism of cyclic nucleotide binding to the GAF domains of phosphodiesterases 2 and 5 /

Wu, Albert Ya-Po. January 2003 (has links)
Thesis (Ph. D.)--University of Washington, 2003. / Vita. Includes bibliographical references (leaves 101-113).
433

Föreställningar om barnet i rätten : En diskursanalytisk studie ur ett barndomssociologiskt perspektiv av domslut rörande 3 § LVU

Svensson, Andrea, Järn, Sofie January 2015 (has links)
Denna studie behandlar barnperspektivets uttryck i domslut avseende tvångsvård av barn under 15 år enligt 3 § Lag (1990:52) med särskilda bestämmelser om vård av unga (LVU). Barnets eget beteende står i fokus i förhållande till rekvisitet socialt nedbrytande beteende i 3 § LVU. Genom en diskursanalys av tio domslut avgjorda enligt 3 § LVU har vi belagt ett underlag för att besvara vårt syfte. Syftet är att undersöka om och i så fall hur barnperspektivet kommer till uttryck i domslut genom förställningar om barnet i relation till hur barnets röst beaktas i förvaltningsrättens bedömning kring barnets bästa.   Mot bakgrund av vår teoretiska och begreppsliga referensram, inbegripande teori och begrepp kännetecknade av socialkonstruktionitiska antaganden och ett barndomssociologiskt perspektiv, dras slutsatsen att det finns indikationer på att förvaltningsrättens barnperspektiv är bristfälligt. Av analysen framgår att barnets perspektiv framförs på ett problematiskt sätt genom att deltagande aktörer i rätten återger barnets utsagor i barnets frånvaro. Detta är problematiskt i den bemärkelse att barnets åsikt och vilja riskerar att modifieras genom återberättande. Studien antyder även att det råder asymmetri barn och vuxen emellan till följd av barnets låga ställning i rätten. Vidare framkommer av studien att förvaltningsrätten innehar makt att kvalificera barnet som subjekt och objekt genom att värdera deltagande aktörers föreställningar om barnet i sin bedömning kring barnets bästa.
434

Techniques to minimize circuitry and improve efficiency for defect tolerance

Rab, Muhammad Tauseef 05 November 2013 (has links)
As technology continues to scale to smaller geometries and newer dimensions (3-D), with increasingly complex manufacturing processes, the ability to reliably manufacture 100% defect-free circuitry becomes a significant challenge. While implementing additional circuitry to improve yield is economically justifiable, this thesis addresses the cost of defect tolerance by providing lower cost solutions or alternatively more defect tolerance for the same cost in state-of-the-art ICs, including three-dimensional ICs (3-D ICs). Conventional defect tolerance techniques involve incorporating redundancy into the design. This thesis introduces novel designs to maximize the utility of spare elements with minimal circuitry overhead, thereby improving the yield. One idea proposed is Selective Row Partitioning (SRP), a technique which allows a single spare column to be used to repair multiple defective cells in multiple columns. This is done by selectively decoding the row address bits when generating the select signals for the column multiplexers. This logically segments the spare column allowing it to replace different columns in different partitions of the row address space. All the chips are identical, but fuses are used to customize the row decoding circuitry on a chip-by-chip basis. An implementation procedure and results are presented which show improvement in overall yield at a minimal overhead cost. Moreover, new yield-enhancing design techniques for 3-D ICs are introduced. When assembling a 3-D IC, there are several degrees of freedom including which die are stacked together, in what order, and with what rotational symmetry. This thesis describes strategies for exploiting these degrees of freedom to reduce the cost and complexity of implementing defect tolerance. One strategy is to enable asymmetric repair capability within a 3-D memory stack by exploiting the degree of freedom that the order of the die in the stack can be selected. This technique optimizes the number of fuses, and in some cases, the number of spares as well, required to implement defect tolerance. Another innovative technique is to exploit rotational symmetry of the dies to do implicit reconfiguration to implement defect tolerance. Results show that leakage power and performance overhead for defect tolerance can be significantly reduced by this technique. / text
435

GSK-3β inhibition promotes oligodendroglial differentiation and remyelination after spinal cord injury

Pan, Yanling, 潘彥伶 January 2015 (has links)
Spinal cord injury (SCI) results in extensive demyelination, leading to deleterious axon degeneration and inability of functional recovery. Remyelination has become a part of the fundamental strategy for SCI repair. Endogenous neural progenitor cells (NPCs) respond to SCI producing progenies and provide a possible source of regenerated oligodedrocytes for remyelination. During development of the central nervous system, glycogen synthase kinase-3 isoform beta (GSK-3β) is involved in multiple pathways that regulate oligodendrocyte differentiation and myelination, and thus may also play an important part in remyelination after SCI. This study aims to investigate (1) the role of GSK-3β in the differentiation of adult spinal cord derived-neural progenitor cells (ASC-NPCs); (2) whether AR-A014418 as a GSK-3β inhibitor, can promote oligodendroglial differentiation of ASC-NPCs; (3) the effect of LiCl, another GSK-3β inhibitor, on functional recovery after SCI; (4) the effects of LiCl on the myelin and axonal preservation after SCI. Neurosphere culture from adult mouse spinal cord was performed to test the effect of GSK-3β inhibitors, LiCl and AR-A014418, on differentiation of ASC-NPCs. Phenotyping of differentiated ASC-NPCs by immunocytochemistry (ICC) was performed to identify oligodendroglia progenitor cells (OPCs) at different stages. It was shown that LiCl (1 mM) and AR-A014418 (5 μM) promoted differentiation of OPCs as labeled by oligodendrocyte lineage-specific markers: PDGFR-α, NG2 and O4, while AR-A014418 was more potent in the OPC differentiation. Moreover, preliminary data from western blot confirmed that ARA014418 (5 μM) treatment increased the expression level of pGSK (inactive form of GSK-3) in differentiated ASC-NPCs. This suggests a possible strategy to modulate endogenous NPC response to SCI: to induce the preferential differentiation of NPCs into oligodendrocyte lineage by inhibiting GSK-3β activity and thus leading to enhanced remyelination by the differentiated oligodendrocytes. Basso Mouse Scale (BMS) open field test was used to evaluate the locomotive function of the spinal cord injured mice. The result showed that LiCl (4 mM, 200 μl) administration delivered locally at the lesion site by osmotic pump for 2 weeks improved functional recovery after SCI. Furthermore, immunohistochemistry (IHC) analyses revealed that LiCl treatment inhibited GSK-3β activity in the 〖Olig2〗^+ OPCs/oligodendrocytes, confirming LiCl as a GSK-3β inhibitor in vivo. Moreover, LiCl treatment better preserved myelin and axons detected by myelin basic protein (MBP) immunostaining and neurofilment-200 (NF-200) immunostaining respectively in the injured spinal cords. All together, the data from our in vitro and in vivo experiments suggested that LiCl treatment after spinal cord injury is beneficial for functional recovery by preventing the loss of myelin and axons after SCI and this effect is mediated via GSK-3β inhibition This study provided evidence for the involvement of GSK-3β in the regulation of OPC differentiation and the subsequent remyelination in the injured adult spinal cord. We propose GSK-3β as an important therapeutic target for SCI repair, LiCl as a potential candidate for SCI clinical treatment and the possibility to manipulate endogenous NPCs after SCI to enhance oligodendrocyte differentiation, remyelination, and ultimately better functional recovery.. / published_or_final_version / Anatomy / Master / Master of Philosophy
436

A four-wing chaotic attractor generated from a new 3-D quadratic autonomous system

QI, G, Chen, G, van Wyk, MA, van Wyk, BJ, Zhang, Y 02 January 2007 (has links)
This paper introduces a new 3-D quadratic autonomous system, which can generate two coexisting single-wing chaotic attractors and a pair of diagonal double-wing chaotic attractors. More importantly, the system can generate a fourwing chaotic attractor with very complicated topological structures over a large range of parameters. Some basic dynamical behaviors and the compound structure of the new 3-D system are investigated. Detailed bifurcation analysis illustrates the evolution processes of the system among two coexisting sinks, two coexisting periodic orbits, two coexisting single-wing chaotic attractors, major and minor diagonal double-wing chaotic attractors, and a four-wing chaotic attractor. Poincare´-map analysis shows that the system has extremely rich dynamics. The physical existence of the fourwing chaotic attractor is verified by an electronic circuit. Finally, spectral analysis shows that the system has an extremely broad frequency bandwidth, which is very desirable for engineering applications such as secure communications.
437

Läsundervisningens organisation i grundskolans tidiga årskurser : En systematisk litteraturstudie om hur lärare i årskurserna F-3 arbetar för att utveckla elevers läsförmåga.

Eriksson, Sofie January 2015 (has links)
Syftet med denna litteraturstudie var att undersöka hur F-3 lärare organiserar och bedriverden tidiga läsundervisningen samt undersöka vilka faktorer som verkar påverkaundervisningen och dess innehåll. Metoden för arbetet är en systematisk litteraturstudie därtidigare empiriska forskningar har analyserats och presenterats. Litteraturen söktes genomsöktjänster och databaser tillgängliga via Högskolan Dalarnas bibliotek i form av LIBRISoch SUMMON. Resultatet visar att lärare ser avkodning och läsförståelse som viktiga delardå eleverna ska utveckla en god läsförmåga. Hur lärarna organiserar den tidigaläsundervisningen ser dock ut på olika sätt. Några olika läsinlärningsteorier speglas ilärarnas sätt att bedriva undervisningen men den främsta metoden verkar dock vara dentraditionella ljudningsmetoden där eleverna i ett tidigt stadium lär sig ords enskildabeståndsdelar. Något som verkar vara generellt i skolorna är att många lärare anordnartidiga läsförberedande aktiviteter för de yngre eleverna där de får möta skriftspråket ilekfulla former. Lärarens kunskaper inom läsinlärningsområdet visas vara en avgörandefaktor för den tidiga läsundervisningen och barnens utveckling av en god läsförmåga.
438

Οικονομετρία και εμπορικό δίκαιο

Θεοφιλάτος, Γεώργιος 26 October 2009 (has links)
Στην παρούσα εργασία έγινε μία προσπάθεια ανάπτυξης της οικονομετρίας σαν εργαλείο για την εξαγωγή συμπερασμάτων και αποφάσεων από τα δικαστήρια. Αφορμή αποτέλεσαν οι υποθέσεις αθέμιτου ανταγωνισμού που πρόσφατα έχουν συμβεί στην χώρα μας, όπου με τη χρήση των ποσοτικών μεθόδων αποδείχτηκαν οι εναρμονισμένες πολιτικές. Περιγράφηκε η αναπτυσσόμενη ανάγκη χρήσης ποσοτικών μεθόδων στο δικαστήριο. Γίνεται αναφορά στο νομικό προηγούμενο Daubert το αποίο περιγράφει ρητά την αποδεκτικότητα μαρτυριών ειδικών επιστημόνων σε δικαστικές διαμάχες (στο νομικό σύστημα της Αμερικής). Αναπτύσσονται τα κριτήρια για να είναι μία οικονομετρική μελέτη αποδεκτή από το δικαστήριο σαν πειστήριο. Βασικές αναφορές στην οικονομετρία. Υποθέσεις που έχουν χρησιμοποιήσει οικονομετρία. Προβλήματα από την χρήση των ποσοτικών μεθόδων στο Νομικό σύστημα. Τέλος μελέτες περιπτώσεων όπου η οικονομετρική ανάλυση είχε τον πρώτο λόγο σαν αποδεικτικό στοιχεία στο δικαστήριο. / In this particular assignment an effort has been made to develop econometrics as a weapon to reach conclusions and decisions of courts. The reason for all this have been the antitrust cases which have recently occurred in our country, where policies agreed among companies have been proved by using quantitive methods. In the court the increasing need to use quantitive methods has been described. A reference has been made concerning the Daubert standard which explicitly describes the acceptance of the testimonies of scientists in litigation (in the legal system of America). What is thoroughly developed are the criteria so that it will be an econometric study which will be accepted by court as evidence. Basic references to econometrics. Cases which have used econometrics. Problems which may arise by the use of quantitive methods in the legal system. Finally, studies of cases where econometrics analysis was the most import evidence in court.
439

Εναπόθεση οξειδίων του πυριτίου με πλάσμα οργανοπυριτικών ενώσεων για την προστασία μεταλλικών επιφανειών απο τη διάβρωση

Βούλγαρης, Χαράλαμπος 14 February 2008 (has links)
Τα λεπτά υμένια οξειδίων του πυριτίου (SiOx) χρησιμοποιούνται σήμερα ευρέως στην μικροηλεκτρονική και στη βιομηχανία συσκευασίας τροφίμων ενώ τα τελευταία χρόνια υπάρχει έντονο ερευνητικό ενδιαφέρον για την εφαρμογή τους στην προστασία μετάλλικών επιφανειών από την διάβρωση. Η χημική εναπόθεση SiOχ με τη χρήση πλάσματος χαμηλής πίεσης του τετρααιθοξυσιλανίου (TEOS) παρουσιάζει μερικά σημαντικά πλεονεκτήματα όπως εναπόθεση σε χαμηλές θερμοκρασίες, ομοιόμορφη κάλυψη της επιφανείας και μεγάλους ρυθμούς εναπόθεσης. Από την άλλη πλευρά, η ιδιαιτερότητα της εναπόθεσης μέσω πλάσματος ΤΕΟS, έγκειται στο γεγονός ότι η δομή, οι ιδιότητες και η χημική σύσταση των παραγόμενων υμενίων εξαρτώνται σημαντικά από τις παραμέτρους της διεργασίας, λόγω της πολυπλοκότητας του πλάσματος του ΤΕΟS. Είναι χαρακτηριστικό ότι ανάλογα με τις συνθήκες εναπόθεσης μπορούν να παραχθούν υλικά που η χημική τους σύσταση ποικίλλει μεταξύ σιλικόνης (SiOxCyHz) και σχεδόν στοιχειομετρικού SiO2. Στην παρούσα εργασία εξετάζεται η επίδραση διαφόρων παραμέτρων της διεργασίας (ολική πίεση, καταναλισκώμενη ισχύς, προεπεξεργασία επιφανείας) στο ρυθμό εναπόθεσης και στη σύσταση των παραγόμενων υμενίων που εναποτέθηκαν σε επιφάνειες διαφόρων κραμάτων του μαγνησίου. Για τη μέτρηση του ρυθμού εναπόθεσης χρησιμοποιήθηκε ανακλαστική συμβολομετρία με λέιζερ και για το προσδιορισμό της χημικής σύστασης φασματοσκοπία υπερύθρου (FTIR). Όσον αφορά τα διαγνωστικά τεστ του πλάσματος, χρησιμοποιήθηκε φασματογραφία μάζας για τον προσδιορισμό της κατανάλωσης της πρόδρομης ένωσης στην εκκένωση και φασματοσκοπία εκπομπής (OES) για την ανίχνευση και ταυτοποίηση των διεγερμένων ειδών στην αέρια φάση. Η αντοχή στη διάβρωση εκτιμήθηκε με τη βοήθεια της ηλεκτροχημικής φασματοσκοπίας εμπέδησης (ΕΙS) και ο χαρακτηρισμός της επιφανείας με μικροσκοπίες SEM και AFM. Οι συνθήκες που παρουσιάζονται τα βέλτιστα αποτελέσματα αντοχής στη διάβρωση, συζητούνται με βάση τη δομή και τη χημική σύσταση των υμενίων καθώς και τις μεταβολές των ιδιοτήτων του πλάσματος. / The silicon oxide (SiOx) thin films are used in microelectronics, in food packaging industry and in the recent years there is an increasing interest of using them as protective coatings for metallic surfaces. The plasma chemical vapor deposition of these films (PECVD) has several advantages, like the deposition at low temperatures, the uniform cover of the surface and the high deposition rates. On the other hand the thing that distinguishes this technique (PECVD) using TEOS as the precursor, is that the structure, the properties and the chemical composition of the deposited films are strongly depended on the variables of the process, because of the complexity of the chemistry of TEOS. The chemical composition of the deposited film can vary from almost total inorganic SiO2 to silicone like (SiOxCyHz). In the present essay, it is examined the effect of various parameters as the consumed power, the total pressure and the surface pre-treatment to the deposition rate and to the chemical composition and structure of the thin film. The films were deposited on aluminium and magnesium alloys. The technique used for measuring the deposition rate was Laser Reflective Interferometry and for the determination of the chemical composition the FTIR Spectroscopy. The evaluation of the corrosion resistance was made by using Electrochemical Impedance Specroscopy (ΕΙS), and the examination of the surfaces by SEM and AFM. The conditions that provided the best results for the corrosion protection of the metallic surfaces are presented according the structure and the chemical composition of the thin film and the changes of plasma properties.
440

The use of induced stereoscopic motion for photographic interpretation

Slingerland, Douglas Alan, 1930- January 1967 (has links)
No description available.

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