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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

Internationella regelverks påverkan på sparbanker i Kalmar län : En studie av Basel III

Sjöman, Pontus January 2015 (has links)
BAKGRUND  De senaste åren har regelverken för banksektorn blivit allt mer omfattande. Regelverket Basel III ställer ökade krav på bankerna gällande såväl kapital som likviditet, och det är i stort sett samma regelverk som gäller för storbanker som för små sparbanker. Sparbanker är en intressant associationsform med en lång historia och de har ofta mycket stor betydelse för de orter där de är verksamma. SYFTE Syftet med denna rapport är att undersöka hur sparbanker i Kalmar län upplever det ökade regelverk som har införts för banker under de senaste åren. I syftet ingår även att undersöka vilka konkreta förändringar som införandet av Basel III har lett till i sparbankernas verksamhet samt om sparbankerna kan leva upp till de ökade kraven. METOD Detta är en kvalitativ studie som bygger på personliga intervjuer med representanter från fyra sparbanker i Kalmar län samt en intervju med en representant från Sparbankernas riksförbund. Studien har ett hermeneutiskt synsätt och studiens resultat är därför präglat av hur jag som uppsatsförfattare har tolkat intervjupersonerna.  REFERENSRAM Detta kapitel innehåller ett resonemang kring finansiella regelverk och kriser samt en beskrivning av Knutsen och Sjögrens kriscykelmodell. Referensramen innehåller även en presentation av Baselkommittén för banktillsyn och en redogörelse för innehållet i Basel III. Slutligen presenteras några av de konsekvenser som införandet av Basel III för med sig. RESULTAT OCH SLUTSATSER Samtliga respondenter är överens om att Basel III inte är anpassat för sparbankernas verksamhet och att det har kommit mycket nya regleringar på kort tid. Införandet av Basel III innebär att sparbankerna måste strukturera om vissa delar av sitt kapital för att nå de nya kraven. Sparbankernas lönsamhet kommer att minska något som en följd av Basel III och införandet av det nya regelverket har inneburit en ökad administrativ börda. Samtidigt är sparbankerna väl rustade inför framtiden och har god likviditet och mycket kapital.
302

Development of III-nitride transistors: heterojunction bipolar transistors and field-effect transistors

Lee, Yi-Che 08 June 2015 (has links)
The fabrication processes development for on III-nitride (III-N) heterojunction bipolar transistors (HBTs), heterojunction field-effect transistors (HFETs) and metal-insulator-semiconductor field-effect transistors (MISFETs) were performed. D.c, microwave and quasi-static I-V and C-V measurements were carried out to characterize the fabricated III-N transistors and diodes. The GaN/InGaN direct-growth HBTs (DG-HBTs) grown on free-standing GaN (FS-GaN) substrates demonstrated a high current gain (hfe) > 110, high current density (JC) > 141 kA/cm2, and high power density (Pdc) > 3 MW/cm2. The first III-N DG-HBT showing fT > 8 GHz and fmax > 1.3 GHz were also demonstrated on sapphire substrates. Recessed-gate AlGaN/AlN/GaN HFETs demonstrated Vth = 0 V with 0.17 V deviation across the sample. Baliga's figure of merit is 240 MW/cm2 was achieved. Current collapse was eliminated and the dynamic on-resistance was reduced by 67% after using a remote-oxygen-plasma treatment. Normally-off recessed-gate AlGaN/AlN/GaN MISFETs with Vth = 0.9 V were also fabricated with the remote-oxygen-plasma treatment. Low leakage current (< 1 pA/mm), high on-off ratio (> 2.2E11) are achieved. These achievements suggest that high-performance III-N transistors are very promising for high-power switching and microwave amplification. Findings concerning remaining process issues and implications for future research are also discussed.
303

Detection of unstable intermediates and mechanistic studies in multisteps, two-electron transfer reactions by cyclic voltammetry and scanning electrochemical microscopy

Chang, Jinho 01 September 2015 (has links)
Unstable Sn(III) intermediates generated in the Sn(IV)/Sn(II) redox reaction in 2 M HBr + 4 M NaBr media were detected by scanning electrochemical microscopy (SECM) and cyclic voltammetry (CV). In CV, the underpotential deposition of Sn(0) and its stripping peaks severely perturbed the analysis of diffusional reactions. In SECM, however, the detection of diffusional Sn(III) bromide species was clearly observed due to the absence of the perturbation from the surface reactions. The ECEC-DISP mechanism in both the reduction and oxidation reactions was proposed via Sn(III) bromide intermediates. CVs at different concentrations of Sn(IV) and at various scan rates were fit by numerical simulations based on the proposed mechanism with good agreement. Enhanced electrochemical reversibility in the Sn(IV)/Sn(II) redox reaction was observed at the elevated temperature of 80 °C. We attributed such observation to changes in the rate of bromide loss from Sn(IV)Br₆²⁻ to Sn(IV)Br₅⁻ based on the CV simulation. In a similar approach, a short-lived intermediate, presumably bromine anion radical Br₂⁻·, was detected in the Br⁻ /Br₃⁻ electro-oxidation reaction in nitrobenzene solution by SECM and CV. The reaction mechanism was proposed based on a detected Br₂⁻· intermediate as follows: (1) the one electron transfer of Br⁻ to Br·, (2) the dimerization of 2Br· to Br₂, (3) the bromide addition reaction of Br₂ to Br₃⁻ , (4) the bromide addition reaction of Br· to Br₂⁻·, and (5) the Br· addition reaction of Br₂⁻· to Br₃⁻. The simulation based on the proposed mechanism fitted well with the experimental SECM and CV results. At last, the applicability of the Sn/Br system as electrolyte for electrochemical energy storage was tested. A redox flow battery was constructed, where the Sn(IV)/Sn(II) reduction was carried out on the negative electrode, while the Br· /Br₂ oxidation was carried out on the positive electrode during charging. Cyclability was tested up to 35 charge/discharge cycles, and 100 % coulombic efficiency was observed in all cycles. However, only 40 % of voltage efficiency was obtained, mainly due to the large irreversibility of the Sn(IV)/Sn(II) redox reaction in the bromide media.
304

Motor unit firing patterns during sustained ischemic submaximal contractions

Shah, Kena Pankajkumar 15 February 2011 (has links)
The aim of this study was to determine motor unit firing patterns during ischemic versus non-ischemic sustained submaximal isometric contractions of the tibialis anterior muscle. 10 healthy adults attended two experimental sessions approximately 48 hours apart. Both sessions were identical except that the fatigue task in one was performed with a pressure cuff placed above the knee and inflated to 180 mm Hg. Three 5s maximum voluntary contractions (MVCs) were performed prior to and after the fatigue task. Each participant held a target force of 20% MVC until endurance time (peak-to-peak tremor amplitude exceeded 5% MVC). Single motor unit firing rates (11 non ischemic, 9 ischemic) were recorded with intramuscular fine wire electrodes. Mean interspike intervals over 5s time bins were calculated at every 5% endurance time. The endurance time for the ischemic (3.7 ± 0.58 min) fatigue task was significantly (p<0.001) shorter than the non-ischemic (9.5 ± 0.57 min) task. There was no significant difference in mean motor unit firing rates between the two conditions (p=0.883). Within both tests, there was a significant decline in firing rate (ischemic initial: 12.95 ± 0.71 Hz, minimum: 11.41 ± 0.81 Hz, p=0.023; non-ischemic initial: 13.13 ± 0.87 Hz, minimum: 11.15 ± 0.48 Hz, p=0.012). The time to minimum firing rate was significantly (p<0.001) less in the ischemic (1.29 ± 0.2 min) compared to non-ischemic (3.14 ± 0.23 min) condition. Muscle ischemia significantly reduced endurance time and the time to minimum firing rate. However, there were no differences in average motor unit firing rates between the two conditions across the relative phases of endurance time. / text
305

Αποχωρισμένα διπλά εκλειπτικά συστήματα στο Μεγάλο Νέφος του Μαγγελάνου από το OGLE III / Modeling of detached binary systems in LMC from OGLE-III

Θεοδοσίου, Άννα 16 May 2014 (has links)
Περίπου το 70% των αστέρων που παρατηρούνται στο σύμπαν είναι μέλη πολλαπλών συστημάτων και η μελέτη τους είναι υψίστης σημασίας για τους αστρονόμους τις τελευταίες δεκαετίες. Τα διπλά εκλειπτικά συστήματα προσφέρουν μοναδικές δυνατότητες μελέτης των αστρικών παραμέτρων και κατ’ επέκταση των θεωριών εξέλιξης εξαιτίας της γεωμετρίας τους και αποτελούν τη βάση της μεθόδου προσδιορισμού αστρονομικών αποστάσεων ως «πρότυπα κεριά» (standard candles). Στην παρούσα εργασία πραγματοποιείται η μοντελοποίηση των καμπυλών φωτός 36 λαμπρών αποχωρισμένων διπλών εκλειπτικών συστημάτων που παρατηρήθηκαν κατά την τρίτη φάση του προγράμματος OGLE στο Μεγάλο Νέφος του Μαγγελάνου και εξάγονται οι φωτομετρικές τους παράμετροι, ώστε τα πιο ενδιαφέροντα από αυτά να επιλεχθούν για περαιτέρω φασματοσκοπικές παρατηρήσεις ως υποψήφιοι δείκτες απόστασης. Στο πρώτο κεφάλαιο πραγματοποιείται μία εισαγωγή στους μεταβλητούς αστέρες, μία αναφορά στην ταξινόμηση των διπλών εκλειπτικών συστημάτων σύμφωνα με το μοντέλο Roche και με τη μορφή της καμπύλης φωτός τους καθώς και στοιχεία που αφορούν τη γεωμετρία τους και τις εξισώσεις της τροχιάς τους. Στο δεύτερο κεφάλαιο περιγράφεται το πρόγραμμα OGLE (Optical Gravitational Lensing Experiment) σκοπός του οποίου είναι η ανίχνευση συμβάντων βαρυτικής μικροεστίασης με κύριους στόχους τα Νέφη του Μαγγελάνου, το Γαλαξιακό Δίσκο και την Κεντρική Περιοχή του Γαλαξία. Ως αποτέλεσμα της χαρτογράφησης των πεδίων αυτών είναι η δημιουργία μίας μεγάλης βάσης δεδομένων μεταβλητών αστέρων για περεταίρω μελέτη. Στο τρίτο κεφάλαιο περιγράφεται αναλυτικά το πρόγραμμα PHOEBE (PHysics Of Eclipsing BinariEs) με το οποίο πραγματοποιήθηκε η μελέτη των καμπυλών φωτός των 36 συστημάτων. Το πρόγραμμα αυτό αποτελεί μία βελτιωμένη έκδοση του προγράμματος WD (Wilson & Devinney 1979) που στηρίζεται στη μέθοδο των διαφορικών διορθώσεων για της εξαγωγή των φωτομετρικών παραμέτρων των συστημάτων. Τέλος στο τέταρτο κεφάλαιο παρουσιάζεται η μέθοδος επιλογής των 36 διπλών εκλειπτικών συστημάτων που μελετήθηκαν, ο προσδιορισμός των βασικών παραμέτρων που εισήχθησαν στο πρόγραμμα, οι φωτομετρικές παράμετροι που διεξήχθησαν καθώς και τα επιστημονικά συμπεράσματα της μελέτης. / Over 70% of the stars in the universe are components of multiple systems. The study of these systems is crucial for the astronomers over the last decades because their parameters can be derived due to their geometry and assumptions can be made about stellar evolution. Moreover these systems are very promising for measuring distances in the universe as “standard candles”. In the present work 36 DEBs were chosen from the third phase of OGLE program from the Large Magellanic Cloud and Light Curve modeling was held via PHOEBE program which is an improved version of WD code (Wilson & Devinney 1979). Photometric parameters of these systems were derived so that the most interesting of these would be potential targets for further spectroscopic observations as distance indicators for the Large Magellanic Cloud.
306

Transformational III-V Electronics

Nour, Maha A. 04 1900 (has links)
Flexible electronics using III-V materials for nano-electronics with high electron mobility and optoelectronics with direct band gap are attractive for many applications. This thesis describes a complementary metal oxide semiconductor (CMOS) compatible process for transforming traditional III-V materials based electronics into flexible one. The thesis reports releasing 200 nm of Gallium Arsenide (GaAs) from 200 nm GaAs / 300 nm Aluminum Arsenide (AlAs) stack on GaAs substrate using diluted hydrofluoric acid (HF). This process enables releasing a single top layer compared to peeling off all layers with small sizes at the same time. This is done utilizing a network of release holes that contributes to the better transparency (45 % at 724 nm wavelengths) observed. Fabrication of metal oxide semiconductor capacitor (MOSCAPs) on GaAs is followed by releasing it to have devices on flexible 200 nm GaAs. Similarly, flexible GaSb and InP fabrication process is also reported to transform traditional electronics into large-area flexible electronics.
307

Passivation of III-V Semiconductor Surfaces

Contreras, Yissel, Muscat, Anthony 08 November 2013 (has links)
Computer processor chips of the last generation are based on silicon, modified to achieve maximum charge mobility to enable fast switching speeds at low power. III-V semiconductors have charge mobilities that are much higher than that of silicon making them suitable candidates for boosting the performance of new electronic devices. However, III-V semiconductors oxidize rapidly in air after oxide etching and the poor quality of the resulting oxide limits device performance. Our goal is to design a liquid-phase process flow to etch the oxide and passivate the surface of III-V semiconductors and to understand the mechanism of layer formation.Self-assembled monolayers of 1-eicosanethiol (ET) dissolved in ethanol, IPA, chloroform, and toluene were deposited on clean InSb(100) surfaces. The InSb passivated surfaces were characterized after 0 to 60 min of exposure to air. Ellipsometry measurements showed a starting overlayer thickness (due to ET, oxides, or both) of about 20 Å in chloroform and from 32 to 35 Å in alcohols and toluene. Surface composition analysis of InSb with X-ray photoelectron spectroscopy after passivation with 0.1 mM ET in ethanol confirmed the presence of ET and showed that oxygen in the Auger region is below detection limits up to 3 min after the passivation. Our results show that a thiol layer on top of a non-oxidized or low-oxide semiconductor surface slows oxygen diffusion in comparison to a surface with no thiol present, making this a promising passivation method of III-V semiconductors.
308

EPIGENETIC REMODELING DURING ARSENICAL-INDUCED MALIGNANT TRANSFORMATION

Jensen, Taylor Jacob January 2008 (has links)
Humans are exposed to arsenicals through many routes with the most common being drinking water. Exposure to arsenic has been associated with an increased incidence of skin, lung, liver, prostate, and bladder cancer. Although the relationship between arsenic exposure and carcinogenesis is well documented, the mechanisms by which arsenic participates in tumorigenesis are not fully elucidated. We evaluated the potential epigenetic component of arsenical action by assessing the histone acetylation and DNA methylation state of 13,000 human gene promoters in a cell line model of arsenical-mediated malignant transformation. We show changes in histone H3 acetylation and DNA methylation occur during arsenical-induced malignant transformation, each of which is linked to the expression state of the associated gene. These epigenetic changes occurred non-randomly and targeted common promoters whether the selection was performed with arsenite [As(III)] or with the As(III) metabolite monomethylarsonous acid [MMA(III)]. The epigenetic alterations of these promoters and associated malignant phenotypes were stable after the removal of the transforming arsenical. One of the affected regions was the promoter of WNT5A. This gene is transcriptionally activated during arsenical induced malignant transformation and its promoter region exhibited alterations in each of the four histone modifications examined which were linked to its transcriptional activation. Experimental reduction of WNT5A transcript levels resulted in abrogated anchorage independent growth, suggesting a participative role for the epigenetic remodeling of this promoter region in arsenical-induced malignant transformation. Taken together, these data suggest that arsenicals may participate in tumorigenesis by stably altering the DNA methylation and histone modifications associated with targeted genes, uncovering a likely set of participative genes and representing a mechanism to potentially explain the latency associated with arsenic-induced malignancy.
309

Characterization of a Novel Promoter Region for the Enteropathogenic Escherichia coli Type III Secretion System Chaperone Gene cesT

Brouwers, Erin 05 December 2011 (has links)
Enteropathogenic Escherichia coli (EPEC) is an enteric pathogen that causes potentially fatal infantile diarrhea. A type III secretion system is employed by EPEC to inject bacterial effector proteins directly into host intestinal epithelial cells. The multivalent chaperone, CesT, interacts with nine effectors and is a significant contributor to EPEC pathogenesis. A putative transcriptional promoter region was identified directly upstream of cesT. In silico analyses identified conserved elements that suggest the cesT promoter is recognized by ?70. Using transcriptional fusions to lux reporter genes I showed that the cesT promoter region is active under conditions known to induce virulence-gene expression. I conclude that the cesT promoter is active early during an in vitro assay, and regulated by different mechanisms than those affecting the Ptir operon promoter.
310

TOOLS FOR IDENTIFYING FUNCTIONS OF TYPE III SECRETION SYSTEM EFFECTORS FROM SHIGELLA FLEXNERI

Sidik, Saima 17 April 2012 (has links)
Shigellae are pathogenic bacteria that cause the disease shigellosis. Two methods for studying secreted effectors encoded by this pathogen’s virulence plasmid are described. First, protein microarrays were used to identify substrates of an E3 ubiquitin ligase called IpaH7.8. Second, a deletion collection containing mutants for every gene on the virulence plasmid was used in two screens: one to identify mutants that elicit atypical levels of Interleukin-8 (IL-8) from U937 cells, and one to identify mutants that bind the dye Congo red abnormally. Although protein microarrays were an ineffective tool, the deletion collection proved valuable. Most mutants were less effective at sequestering Congo red than wild-type S. flexneri, although this ability was enhanced in several mutants. Four mutants, ?ospB, ?orf186, ?mxiH and ?mxiK, elicited higher levels of IL-8 from U937 cells than wild type S. flexneri. These results validate the use of the deletion collection as a tool for studying bacterial pathogenesis.

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