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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.
1

Kawasaki syndrome search for the etiological agent, diagnostic markers and insights into pathogenesis /

Chua, Pong Kian. January 2001 (has links)
Thesis (Ph. D.)--University of Hawaii at Manoa, 2001. / Includes bibliographical references (leaves 127-162).
2

Some Aspects of the Water Packing Problem

Duarte, Durval 04 1900 (has links)
This is Part B of Thesis. / <p> This report is divided into two parts. The first part contains the results of a simulation performed by the two-phase thermohydraulics code Firebird. </p> <p> The second part of this report deals with the "water packing" problem. Its mathematical and physical interpretations are discussed in detail and a method for identifying a transition node together with an alternate mathematical treatment of the boiling boundary are also included.</p> / Thesis / Master of Engineering (MEngr)
3

Sentinel Node in Clinical Practice : Implications for Breast Cancer Treatment and Prognosis

Andersson, Yvette January 2012 (has links)
The introduction of sentinel lymph node biopsy (SLNB) has conveyed several new issues, such as the risk of false negativity, long-term consequences, the prognostic significance of micrometastases and whether ALND can be omitted in sentinel lymph node- (SLN) positive patients. Archived SLN specimens from 50 false negative patients and 107 true negative controls were serially sectioned and stained with immunohistochemistry. The detection rate of previously unknown metastases did not differ between the false and the true negative patients. The risk of false negativity was higher in patients with multifocal or hormone receptor-negative tumours, or if only one SLN was found. In a Swedish multicentre cohort, 2216 SLN-negative patients in whom ALND was omitted were followed up for a median of 65 months. The isolated axillary recurrence rate was only 1.0%, and the overall survival was high (93%). The survival of 3369 breast cancer patients (2383 node-negative (pN0), 107 isolated tumour cells (pN0(i+), 123 micrometastases (pN1mi) and 756 macrometastases (pN1)) was analysed. The 5-year cause-specific and event-free survival was worse for pN1mi and pN1 patients than for pN0 patients. There was no difference in survival between pN0(i+) and pN0 patients. Tumour and SLN characteristics in 869 SLN-positive patients were compared between those with and without non-SLN metastases, and the Tenon score was calculated. The risk of non-SLN metastases was higher in case of SLN macrometastases (compared with micrometastases), a high positive/total SLN ratio and Elston grade 3 tumours, and increased with increasing tumour size. The area under the curve (AUC) for the Tenon score was 0.65, and the test thus performed inadequately in this population. In conclusion, despite the risk of false negativity, SLNB with omission of ALND in SLN-negative patients appears to be safe even in the long term. The presence of micrometastases is of prognostic importance and should entail adjuvant treatment. The need for ALND in patients with SLN micro- and even macrometastases has been questioned, but the occurrence of non-SLN metastases is hard to predict, and strong evidence for the safe omission of ALND is lacking.
4

Broadcasting Support in Mobile Ad Hoc Wireless Local Area Networks

Chang, Shu-Ping 01 July 2003 (has links)
Broadcasting is a fundamental primitive in local area networks (LANs).Operations of many data link protocols, for example, ARP (Address Resolution Protocol) and IGMP (Internet Group Management Protocol), must rely on this LAN primitive. To develop the broadcasting service in mobile ad hoc wireless LANs (WLANs) is a challenge. This is because a mobile ad hoc WLAN is a multi-hop wireless network in which messages may travel along several links from the source to the destination via a certain path. Additionally, there is no fixed network topology because of host moving. Furthermore, the broadcast nature of a radio channel makes a packet be transmitted by a node to be able to reach all neighbors. Therefore, the total number of transmissions (forward nodes) is generally used as the cost criterion for broadcasting. The problem of finding the minimum number of forward nodes in a static radio network is NP-complete. Almost all previous works, therefore, for broadcasting in the WLAN are focusing on finding approximation approaches in a, rather than, environment. In this paper, we propose a novel distributed protocol in WLANs to significantly reduce or eliminate the communication overhead in addition to maintaining positions of neighboring nodes. The important features of our proposed protocol are the adaptability to dynamic network topology change and the localized and parameterless behavior. The reduction in communication overhead for broadcasting operation is measured experimentally. From the simulation results, our protocol not only has the similar performance as the approximation approaches in the static network, but also outperforms existing ones in the adaptability to host moving.
5

Computational investigation of the mechanisms underlying the cardiac pacemaker and its dysfunction

Wang, Ruoxi January 2016 (has links)
The sinoatrial node is the primary cardiac pacemaker, which is responsible for generating spontaneous depolarisation of cellular membranes, leading to pacemaking action potentials that control the initiation and regulation of the rhythms of the heart. Previous studies in experimental electrophysiology have gathered a large amount of experimental data about the mechanisms of cardiac pacemaking activities at the molecular, ionic and cellular levels, however, the precise mechanisms underlying the genesis of spontaneous pacemaking action potentials still remain controversial. Mathematical models of the electrophysiology provide a unique alternative tool complimentary to experimental investigations, enabling us to analyse the fundamental physiological mechanisms of cardiac pacemaking activities in an efficient way that would be more difficult to conduct in experimental approaches. In this thesis, an integrated model, incorporating the detailed cellular ion channel kinetics, multi-compartment intracellular Ca2+ handling system and cell morphology, was developed for simulating the spontaneous pacemaking action potentials as well as the stochastic nature of local Ca2+ dynamics in the murine SA node cells. By using the model, the ionic mechanisms underlying the automaticity of primary cardiac pacemaking cells were investigated, the individual role of the ‘membrane clock’ (the cell membrane events) and ‘Ca2+ clock’ (intracellular Ca2+ activities) on generating the pacemaking action potentials were examined. In addition, the model also considered the regulation of the autonomic nervous systems on cardiac pacemaking action potentials. For the first time, competitive regulation of electrical action potentials of the murine SA node cells by the circadian sympathetic and parasympathetic systems during 24-hours were investigated. Furthermore, the individual role of the neurotransmitters, ACh- and ISO-induced actions on variant ion channel and Ca2+ handling in regulating cardiac pacemaking action potentials were also analysed. At the tissue level, an anatomically detailed 2D model of the intact SA node and atrium was developed to investigate the ionic mechanisms underlying sinus node dysfunctions in variant genetic defect conditions. Effects of these genetic defects in impairing cardiac pacemaker ability in pacing and driving the surrounding atrium as seen in the sinus node dysfunction were investigated.
6

Utilization Patterns of Lymph Node Dissection in Endometrial Cancer Patients Without Distant Metastasis in the United States

Alyea, Jennifer Marie 06 1900 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Endometrial cancer is the most common gynecologic cancer in the United States, and patients with early-stage endometrioid adenocarcinoma have a favorable prognosis. Over the past decade, the gynecologic oncology community has debated whether potential harms of systematic lymph node dissection (LND) outweigh potential benefits for these patients. To minimize number of nodes removed, sentinel lymph node dissection (SLND) is under investigation as an alternative. However, ongoing uncertainty of LND/SLND best practices may result in variations in disease management and discrepant outcomes. Methods Three retrospective cohort studies examined LND/SLND use in patients with endometrioid adenocarcinoma. Two examined temporal and geographic variations, respectively, utilizing the Surveillance, Epidemiology, and End Results (SEER) 18 dataset for the years 2004 through 2015. The third used the SEER-Medicare dataset from 2003 through 2016 to quantify and compare the risk of developing 6-month post-surgical lymphedema, lymphocele, hemorrhage, ileus, infection, thrombosis, and all-cause death by number of lymph nodes removed (0, 1-4, 5-9, or 10+). Results Time trend analyses found LND increased from 2004 through 2008, followed by a significant decline through 2015. SLND was rare and did not increase significantly. Significant geographic variation existed for LND use but not SLND. Per 1,000 patients, analyses of 6-month post-surgical complications found 6.5 experienced lymphedema, 3.9 experienced lymphocele, 15.7 experienced hemorrhage, 28.7 experienced ileus, 37.1 experienced infection, 18.6 experienced thrombosis, and 19.8 died. Controlling for size of primary tumor, tumor grade, comorbidities, race/ethnicity, age at diagnosis, adjuvant chemotherapy, and radiotherapy, adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) showed greater risk for ileus (HR: 1.53; 95% CI: 1.24-1.90), infection (HR: 1.52; 95% CI: 1.25-1.83), and thrombosis (HR: 1.41; 95% CI: 1.09-1.82) when comparing removal of 10+ nodes versus 0 nodes. Conclusion Overall, these studies found significant temporal and geographic variation in LND, as well as increasing risk of post-surgical complications associated with increasing numbers of lymph nodes removed. Should continued research into SLND find strong evidence that it effectively detects cancer spread, patients may benefit through decreased risk of post-surgical ileus, infection, and thrombosis.
7

Feasibility of a Bluetooth Based Structural Health Monitoring Telemetry System

Uchil, Vilas, Kosbar, Kurt 10 1900 (has links)
International Telemetering Conference Proceedings / October 22-25, 2001 / Riviera Hotel and Convention Center, Las Vegas, Nevada / The Bluetooth standard is intended to provide short-range (10-100 meter) wireless connectivity between mobile and desktop devices. It was developed as a replacement for short cables, and has the ability to form ad-hoc networks. This paper explores the feasibility of using Bluetooth devices for structural health monitoring telemetry applications. We describe the configuration of a small ad-hoc network using Bluetooth modules and micro-controllers to simulate a telemetry application and thus evaluate the general framework of distributed, reliable, and secure, wireless communications required for telemetry.
8

SMART : an innovative multimedia computer architecture for processing ATM cells in real-time

Cashman, Neil January 1998 (has links)
No description available.
9

Predictors of Auxillary Lymph Node Involvement in Screen Detected Breast Cancer

Chen, Wan Qing January 2004 (has links)
Background: Axillary lymph node dissection as routine part of breast cancer treatment has been questioned in relation to the balance between benefits and morbidity. The purpose of this study is to determine the association of tumor size, age and histological grade with axillary lymph node metastasis, to determine if some patients could be exempted from axillary dissection. Methods: The data are derived from BreastScreen NSW, the government sponsored population-based breast screening program. In New South Wales (NSW) Australia between 1995 and 2002, 7,221 patients with invasive breast carcinoma were diagnosed and 5,290 patients were eligible for this study. The relationship between incidence of positive axillary lymph nodes and three study factors (tumor size, age and histological grade) was investigated by univariate and multivariate analysis. Logistic regression models were used to predict probability of axillary metastases. Results: The incidence of axillary lymph node metastases was 28.6% (95% CI: 27.4%- 29.8%). Univariate analysis showed that age, tumor size and histological grade were significant predictors of axillary lymph node metastases (p<0.0001). Multivariate analysis identified age, tumor size and histological grade remained as independent predictors (p<0.0001). From multivariate analysis, patients with T1a (Less than or equal to 5mm) and grade I tumors regardless of age had 5.2% (95% CI: 1.2%- 9.3%) frequency of node metastases. Patients 70 years or older with grade I, T1a and T1b (6-10mm) tumors had 4.9% (95% CI: 3.2%- 7.5%) and 6.6% (95% CI: 5.3%-8.3%) predicted frequency of node metastases. Conclusions: Tumor size, age and histological grade are predictors of axillary lymph node metastases. Routine axillary lymph node dissection could be avoided in some patient groups with a low frequency of involved lymph nodes if the benefits are considered to exceed the risks.
10

Partition Timing Routing Protocol in Wireless Ad Hoc Networks

Lin, Tsung-Hsien 07 July 2003 (has links)
Ad Hoc Networks are transmission networks on the structure of wireless networks by consisting of many mobile hosts. But it is no need to use any support by other communication infrastructures like Base Stations, and directly use wireless networks for data-transmission. Because the feature of per host as fast movement, every host can join or go away as it likes, thus, the topology appeared from Ad Hoc networks will have higher probability to make packet loss or transmission delay and cause network flooded to do unnecessary re-send and lose the flow of running data. We will explain generally some relative protocols of setting up routes and possible problems. Besides, describe relative researches of how to solve and reduce the possibility of problem happened. Then, we will bring up a new constructive protocol (Partition-Timing Routing Protocol¡APTR), the protocol can adjust neighboring nodes of covered scope to select certain node to be own core node, if any covered node needs to transmit data to others outside the scope, it has to be managed by core node. Besides, the timing for update and adjust data of per covered scope is different too and not as same as other ways which update timing is at the same time to reduce the load of the entirely network and more changeable. Furthermore, it may increase the rate of update of per scope to get the target of succeeding data-transmission. The simulation results will appear that the load and possibility of data transmission has more advantages than other ways.

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