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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.
291

Molecular characterization of the Ro52 autoantigen and its disease related epitopes /

Ottosson, Lars, January 2005 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2005. / Härtill 5 uppsatser.
292

Bilateral versus unilateral mandibular nerve block anesthesia in a pediatric population a comparison of the incidence of trauma : a report submitted in partial fulfillment ... for the degree of Master of Science in Pediatric Dentistry ... /

College, Courtney R. January 1997 (has links)
Thesis (M.S.)--University of Michigan, 1997. / Includes bibliographical references.
293

Avaliação do custo e da efetividade da radiofrequência na dor cervical crônica com componentes autonômicos simpático e somático em um hospital público / Cost-effectiveness of radiofrequency for chronic neck pain with sympathetic and somatic components in a Public Teaching Hospital in Brazil

Veridiana Marques Rebello Zuccolotto 29 September 2017 (has links)
Introdução: Avaliar a relação do custo e da efetividade da radiofrequência (RF) em relação ao bloqueio seqüencial na Síndrome Dolorosa Complexa Regional-tipo I (SDCR-I). Métodos: 15 pacientes com dor somática e autonômica cervical foram submetidos a bloqueio torácico simpático, combinado com bloqueio facetário cervical bilateral por 4 semanas. Esta seqüência foi repetida quando a dor atingiu VAS 4 cm, e este período foi definido como tempo de analgesia. Posteriormente, os mesmos pacientes foram submetidos a um bloqueio teste seguido de modulação de RF do gânglio simpático torácico e ablação de ramos facetários medianos cervicais. Os pacientes atuaram como seu próprio controle relacionado à analgesia, atividades rotineiras e padrão de sono. Resultados: 13 pacientes completaram o estudo. O tempo de analgesia após a sequência de 4 bloqueios foi de 4 ± 1 mês e o custo anual R$ 15.000,00. O tempo de analgesia após RF foi de 13 ± 2 meses (p <0,001) e os custos foram reduzidos em 26% no primeiro ano e 34% -38% nos anos seguintes, com extrapolação. A qualidade de vida melhorou para ambos os tratamentos (p> 0,05). Não houve efeitos adversos. Discussão: A RF resultou em analgesia de 13 meses comparada a 4 meses após os bloqueios clássicos e melhora na capacidade física e no padrão de sono. Além disso, a RF foi rentável e reduziu as taxas em 23% durante a avaliação do primeiro ano, seguida de uma redução de custos de 32% a 36% nos anos seguintes, com extrapolação. / Objectives: To evaluate cost-effectiveness of radiofrequency (RF) compared to sequential block in Complex Regional Pain Syndrome-I (CRPS). Methods: 15 patients with cervical somathic and autonomic pain were submitted to a 4- weekly sympathetic thoracic block, combined to bilateral cervical facetary block. This sequence was repeated when pain reached VAS 4-cm, and this period was defined as time of analgesia. Thereafter, same patients were submitted to a test block followed by RF modulation of thoracic sympathetic ganglion and ablation of facetary cervical median branches. Patients acted as their own control related to analgesia, routine activities, sleep pattern and costs. Results: 13 patients completed the study. The analgesia time after the 4-block sequence was 4±1 months and the annual costs USA$5000. Analgesia time after RF was 13±2 months (p<0.001) and costs were reduced by 26% in the first year and 34%-38% in the following years extrapolation. Quality of life improved for both treatments (p> 0.05). There were no adverse effects. Discussion: RF resulted in 13-month compared to 4-month analgesia after the classical 4- weekly blocks, and improved physical capacity and sleep pattern. Besides that, RF was costeffective, and reduced rates by 23% during the first-year evaluation, followed by 32%-36% cost reduction in following years, by extrapolation.
294

Automatická detekce srdečních patologií pomocí vysokofrekvenčních složek komplexu QRS / Automatic detection of heart pathologies using high-frequency components of QRS complex

Daňová, Ľudmila January 2020 (has links)
The aim of this thesis is to analyse high-frequency ECG to detect some heart diseases. This is performed with averaging of selected QRS complexes for each lead of the signal; these are thenfilteredin range 500-1 000 Hz. After that the envelope of the signal is done and here the peaks are detected. Based on mutual positions of this peaks, it is possible to detectwhat kind od signal we treat.
295

Automatická detekce srdečních patologií pomocí vysokofrekvenčních složek komplexu QRS / Automatic detection of heart pathologies using high-frequency components of QRS complex

Daňová, Ľudmila January 2021 (has links)
The aim of this thesis is to analyse high-frequency ECG to detect some heart diseases. This is performed with averaging of selected QRS complexes for each lead of the signal; these are then filtered in range 500-1 000 Hz. After that the envelope of the signal is done and here the peaks are detected. Based on mutual positions of this peaks, it is possible to detect what kind od signal we treat.
296

Minimal Sufficient Statistics for Incomplete Block Designs With Interaction Under an Eisenhart Model III

Kapadia, C. H., Kvanli, Alan H., Lee, Kwan R. 01 January 1988 (has links)
The purpose of this paper is to derive minimal sufficient statistics for the balanced incomplete block design and the group divisible partially balanced incomplete block design when the Eisenhart Model III (mixed model) is assumed. The results are identical to Hultquist and Graybill's (1965) and Hirotsu's (1965) for the same model without interaction, except for the addition of a statistic, ∑ijY2ij•.
297

SELF-ASSEMBLED POLYSTYRENE-BLOCK-POLY (ETHYLENE OXIDE) (PS-b-PEO) MICELLE MORPHOLOGIES IN SOLUTION

Bhargava, Prachur 02 October 2007 (has links)
No description available.
298

Performance Evaluation of Spatial Modulation and QOSTBC for MIMO Systems

Anoh, Kelvin O.O., Abd-Alhameed, Raed, Okorafor, G.N., Noras, James M., Rodriguez, Jonathan, Jones, Steven M.R. 21 July 2015 (has links)
Yes / Multiple-input multiple-output (MIMO) systems require simplified architectures that can maximize design parameters without sacrificing system performance. Such architectures may be used in a transmitter or a receiver. The most recent example with possible low cost architecture in the transmitter is spatial modulation (SM). In this study, we evaluate the SM and quasi-orthogonal space time block codes (QOSTBC) schemes for MIMO systems over a Rayleigh fading channel. QOSTBC enables STBC to be used in a four antenna design, for example. Standard QO-STBC techniques are limited in performance due to self-interference terms; here a QOSTBC scheme that eliminates these terms in its decoding matrix is explored. In addition, while most QOSTBC studies mainly explore performance improvements with different code structures, here we have implemented receiver diversity using maximal ratio combining (MRC). Results show that QOSTBC delivers better performance, at spectral efficiency comparable with SM.
299

Exploration of Thorium Amides and Alkyls

Hannah Nicole Kline (14210090) 04 December 2022 (has links)
<p>Metal alkyls have a variety of uses including important intermediates in a variety of  processes. In this research, a thorium bis-alkyl species was fully characterized and explored for its potential reactivity, specifically for the formation of thorium bis-amide complexes. A series of three thorium bis-amide complexes was synthesized and characterized in this work. Additionally, several pathways have been attempted to synthesize an actinide alkylidene within this project including the use of a homoleptic tetrabenzyl complex, the use of diazoalkanes through the loss of dinitrogen, deprotonation of alkyls, and reducing a metallacycle complex. However, many of these did not result in products that suggest that an alkylidene was formed. These reactions ranged from being thermally unstable, decomposing, not reacting, or forming multiple products and being unable to discern one major product.<br> </p>
300

Structure-property relationships in segmented copolymers

Tyagi, D. K. January 1985 (has links)
The structure-property relationships for various segmented copolymers were investigated. A number of mechanical and thermal characteristics were determined. The morphology was characterized by SAXS with respect to size and dispersion of domains; degree of phase separation and the domain interfacial thickness. a. Novel segmented copolymers were synthesized using amino terminated polydimethylsiloxane oligomers as the soft component and various hard component. lt was found that the performance of these copolymers was affected by the varying the hard segment linkages, hard segment content, soft segment MW, stiffness of the siloxane backbone, and amount of chain extender. Two-phase nature of these copolymers was verified by dynamic mechanical, thermal, and SAXS studies. The phase separation was found to occur in these copolymers with as little as 6% HS. These materials displayed behavior similar to the segmented polyurethanes and were found to be superior to the unfilled silicone elastomers. The final materials were used as reasonable models for investigating various methods for determining the interfacial layer thickness between the hard and soft phase. Specifically, due to the fact that there is no hard segment length distribution as is the usual case for segmented urethanes, these materials have some degree of model characteristics. Utilizing Porod's law, and appropriate analysis, both positive and negative deviations were found in the systematic series of copolymers with the degree of positive and negative character dependent upon composition. Negative deviations were accounted for in terms of a finite interfacial thickness which turned out to be relatively small as anticipated, while the positive deviations arose due to isolated hard segments that reside within the soft segment matrix, concentration fluctuations. ln calculating the interfacial thickness, several methods were applied and in general, close agreement was obtained. Finally, correlation function analysis in conjunction with determination of the coherent Porod lengths, etc. were determined and discussed accordingly. b. The structure-property behavior of novel 'water extended' segmented polyurethane-urea copolymers was also investigated. These copolymers were synthesized by utilizing the dehydration characteristics of tertiary alcohols at sufficiently high temperature in weak acidic medium. Mechanical, thermal, dynamic mechanical, and x-ray experiments were carried out to characterize the morphology and properties of these segmented copolymers of systematically varying hard segment content, soft segment MW, block length, and hard segment type. lt was observed that these properties depended primarily on the degree of order in the hard domains and the order could be improved by increasing either the HS content at constant soft segment MW or soft segment molecular weight at the same HS content. The results obtained for these materials were compared with those from conventional polyurethanes to investigate the effect of intermolecular hydrogen bonding on molecular arrangement. c. The final series of segmented copolymers studied were based on polysulfone and polydimethylsiloxane, synthesized by solution polymerization. lt is shown that by varying the length of the segments for each phase and their relative content, it is possible to alter the mechanical and thermal characteristics. The mechanical response was also influenced according to which phase is predominantly continuous. In addition to dynamic mechanical and SAXS measurements, the evidence of the two-phase structure was obtained by TEM. / Ph. D. / incomplete_metadata

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