• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 1047
  • 235
  • 136
  • 88
  • 64
  • 31
  • 30
  • 25
  • 22
  • 19
  • 14
  • 12
  • 11
  • 10
  • 10
  • Tagged with
  • 2102
  • 487
  • 296
  • 262
  • 253
  • 192
  • 178
  • 169
  • 141
  • 140
  • 137
  • 126
  • 123
  • 108
  • 103
  • 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

A study of the delay-lock tracker.

Boyarsky, Abraham. January 1968 (has links)
No description available.
2

A study of the delay-lock tracker.

Boyarsky, Abraham. January 1968 (has links)
No description available.
3

Experiences from detection to diagnosis : lessons learned from patients with high-risk oral lesions

Biggar, Heather Caroline 05 1900 (has links)
Oral cancer is the 6th most common cancer in the world, with a poor prognosis and frequent late-stage diagnosis, which significantly impacts survival and quality of life. The key to better control of this disease is early detection, preferably at a precancerous stage. In order to facilitate this early detection and diagnosis, it is critical to identify the factors potentially impacting on the time lag from initial detection to diagnostic biopsy. The overall goal is to develop effective strategies for early identification of oral cancers in order to achieve better control over this disease. There are 2 components in this thesis: the objectives of part I (personal interview) were 1) to develop an interview-style questionnaire, 2) to collect data from patients with high-risk oral lesions (HRL’s) and 3) to characterize the experiences of these individuals that may have impacted the time interval leading up to diagnosis. The objectives of Part II (focus group discussion) were 1) to gather feedback regarding the questionnaire developed in Part I, 2) to obtain recommendations for future planning and delivery of province-wide questionnaire and 3) as a group, to share information on patients’ experiences to diagnosis and patients’ perspectives on their interactions with health professionals (HP’s) throughout this journey. An interview-style questionnaire was developed to collect both qualitative and quantitative data on patients’ experiences. Forty patients with HRL’s diagnosed within 12 months were recruited and interviewed in the Dysplasia Clinic of the BC Oral Cancer Prevention Program. Two focus groups were conducted and feedback from participants regarding the questionnaire and patients’ experiences was recorded. Among 40 patients interviewed, 21 (53%) initially self-identified their lesions (SIG) and 19 (47%) were identified by health professional screening (PSG; 84% by dental professionals). The SIG showed higher rates of invasive SCC at diagnosis as compared to those in the PSG (76% vs. 32%, P = 0.01) and SIG took twice as long to have the initial biopsy performed as the PSG (23 ± 52 vs. 11 ± 28 months). Notably, the main symptom of patients in SIG was pain or presence of non-healing ulcers (18/21; 86%). In contrast, all lesions in PSG were asymptomatic. The mean time from detection to diagnosis was 17.5 ± 42.3 months (range: 0-240 months). Fourteen patients (35%) experienced a time lag of greater than 6 months from first detection of an oral lesion until the first diagnostic biopsy was performed. Both patient and professional factors impact on the time lag. The main contributing factors for this time lag include both patient factors (a lack of concern, fear, and a lack of oral cancer awareness) and the professional factors (lack of knowledge in differentiating high-risk lesions, delay in initiating the referral or ‘watch and wait’, and delay in scheduling of referral appointments to the specialists). Focus group results supported the format and content of the questionnaire, provided input in designing of future province-wide survey and emphasized that patients require continued post-diagnostic and treatment care. A general lack of awareness of oral cancer in general population and in HP’s in addition to a lack of screening activities have been brought forward as critical factors that result in delay to diagnosis. In conclusion, these results suggest HP’s, especially dental professionals, can play a critical role in early identification of HRL’s at an asymptomatic, pre-invasive stage through regular screening. Strategies in raising awareness of oral cancer in both the general population and among HP’s are essential for early identification of oral cancers in order to achieve better control over this disease.
4

Experiences from detection to diagnosis : lessons learned from patients with high-risk oral lesions

Biggar, Heather Caroline 05 1900 (has links)
Oral cancer is the 6th most common cancer in the world, with a poor prognosis and frequent late-stage diagnosis, which significantly impacts survival and quality of life. The key to better control of this disease is early detection, preferably at a precancerous stage. In order to facilitate this early detection and diagnosis, it is critical to identify the factors potentially impacting on the time lag from initial detection to diagnostic biopsy. The overall goal is to develop effective strategies for early identification of oral cancers in order to achieve better control over this disease. There are 2 components in this thesis: the objectives of part I (personal interview) were 1) to develop an interview-style questionnaire, 2) to collect data from patients with high-risk oral lesions (HRL’s) and 3) to characterize the experiences of these individuals that may have impacted the time interval leading up to diagnosis. The objectives of Part II (focus group discussion) were 1) to gather feedback regarding the questionnaire developed in Part I, 2) to obtain recommendations for future planning and delivery of province-wide questionnaire and 3) as a group, to share information on patients’ experiences to diagnosis and patients’ perspectives on their interactions with health professionals (HP’s) throughout this journey. An interview-style questionnaire was developed to collect both qualitative and quantitative data on patients’ experiences. Forty patients with HRL’s diagnosed within 12 months were recruited and interviewed in the Dysplasia Clinic of the BC Oral Cancer Prevention Program. Two focus groups were conducted and feedback from participants regarding the questionnaire and patients’ experiences was recorded. Among 40 patients interviewed, 21 (53%) initially self-identified their lesions (SIG) and 19 (47%) were identified by health professional screening (PSG; 84% by dental professionals). The SIG showed higher rates of invasive SCC at diagnosis as compared to those in the PSG (76% vs. 32%, P = 0.01) and SIG took twice as long to have the initial biopsy performed as the PSG (23 ± 52 vs. 11 ± 28 months). Notably, the main symptom of patients in SIG was pain or presence of non-healing ulcers (18/21; 86%). In contrast, all lesions in PSG were asymptomatic. The mean time from detection to diagnosis was 17.5 ± 42.3 months (range: 0-240 months). Fourteen patients (35%) experienced a time lag of greater than 6 months from first detection of an oral lesion until the first diagnostic biopsy was performed. Both patient and professional factors impact on the time lag. The main contributing factors for this time lag include both patient factors (a lack of concern, fear, and a lack of oral cancer awareness) and the professional factors (lack of knowledge in differentiating high-risk lesions, delay in initiating the referral or ‘watch and wait’, and delay in scheduling of referral appointments to the specialists). Focus group results supported the format and content of the questionnaire, provided input in designing of future province-wide survey and emphasized that patients require continued post-diagnostic and treatment care. A general lack of awareness of oral cancer in general population and in HP’s in addition to a lack of screening activities have been brought forward as critical factors that result in delay to diagnosis. In conclusion, these results suggest HP’s, especially dental professionals, can play a critical role in early identification of HRL’s at an asymptomatic, pre-invasive stage through regular screening. Strategies in raising awareness of oral cancer in both the general population and among HP’s are essential for early identification of oral cancers in order to achieve better control over this disease.
5

Experiences from detection to diagnosis : lessons learned from patients with high-risk oral lesions

Biggar, Heather Caroline 05 1900 (has links)
Oral cancer is the 6th most common cancer in the world, with a poor prognosis and frequent late-stage diagnosis, which significantly impacts survival and quality of life. The key to better control of this disease is early detection, preferably at a precancerous stage. In order to facilitate this early detection and diagnosis, it is critical to identify the factors potentially impacting on the time lag from initial detection to diagnostic biopsy. The overall goal is to develop effective strategies for early identification of oral cancers in order to achieve better control over this disease. There are 2 components in this thesis: the objectives of part I (personal interview) were 1) to develop an interview-style questionnaire, 2) to collect data from patients with high-risk oral lesions (HRL’s) and 3) to characterize the experiences of these individuals that may have impacted the time interval leading up to diagnosis. The objectives of Part II (focus group discussion) were 1) to gather feedback regarding the questionnaire developed in Part I, 2) to obtain recommendations for future planning and delivery of province-wide questionnaire and 3) as a group, to share information on patients’ experiences to diagnosis and patients’ perspectives on their interactions with health professionals (HP’s) throughout this journey. An interview-style questionnaire was developed to collect both qualitative and quantitative data on patients’ experiences. Forty patients with HRL’s diagnosed within 12 months were recruited and interviewed in the Dysplasia Clinic of the BC Oral Cancer Prevention Program. Two focus groups were conducted and feedback from participants regarding the questionnaire and patients’ experiences was recorded. Among 40 patients interviewed, 21 (53%) initially self-identified their lesions (SIG) and 19 (47%) were identified by health professional screening (PSG; 84% by dental professionals). The SIG showed higher rates of invasive SCC at diagnosis as compared to those in the PSG (76% vs. 32%, P = 0.01) and SIG took twice as long to have the initial biopsy performed as the PSG (23 ± 52 vs. 11 ± 28 months). Notably, the main symptom of patients in SIG was pain or presence of non-healing ulcers (18/21; 86%). In contrast, all lesions in PSG were asymptomatic. The mean time from detection to diagnosis was 17.5 ± 42.3 months (range: 0-240 months). Fourteen patients (35%) experienced a time lag of greater than 6 months from first detection of an oral lesion until the first diagnostic biopsy was performed. Both patient and professional factors impact on the time lag. The main contributing factors for this time lag include both patient factors (a lack of concern, fear, and a lack of oral cancer awareness) and the professional factors (lack of knowledge in differentiating high-risk lesions, delay in initiating the referral or ‘watch and wait’, and delay in scheduling of referral appointments to the specialists). Focus group results supported the format and content of the questionnaire, provided input in designing of future province-wide survey and emphasized that patients require continued post-diagnostic and treatment care. A general lack of awareness of oral cancer in general population and in HP’s in addition to a lack of screening activities have been brought forward as critical factors that result in delay to diagnosis. In conclusion, these results suggest HP’s, especially dental professionals, can play a critical role in early identification of HRL’s at an asymptomatic, pre-invasive stage through regular screening. Strategies in raising awareness of oral cancer in both the general population and among HP’s are essential for early identification of oral cancers in order to achieve better control over this disease. / Dentistry, Faculty of / Graduate
6

Automated Delay Estimation at Signalized Intersections: Phase I Concept and Algorithm Development

Forbush, Taylor R. 16 March 2011 (has links) (PDF)
Currently there are several methods to measure the performance of surface streets, but their capabilities in dynamically estimating vehicle delay are limited. The objective of this research is to develop a method to automate traffic delay estimation in real-time using existing field traffic data collection technologies. This research has focused on method and algorithm development that can be applied to existing technologies. Two algorithms were developed to run automatically using Microsoft Excel and Visual Basic to calculate traffic delay from data collected from existing vehicle detection. The algorithms were developed using computer modeling software to simulate different lane configurations. The lane configurations tested were through-only lanes, through lanes with a midblock driveway, and through lanes with a turning bay. Different levels of volumes were simulated for each of the lane configurations. Results were promising for each lane configuration. The through-only configuration showed excellent results with maximum errors less than 3 seconds per vehicle for each test. The through lanes with the driveways test was evaluated using added detection at the driveway locations and no detection at the driveways. Results using the driveway sensors had 93 percent of the calculated average delays with less than 5 seconds per vehicle of error. Results without the driveway sensors had 84 percent of the calculated average delays with less than 5 seconds of error. Results for the turning bay configuration had 94 percent of the calculated turning bay results with less than 5 seconds per vehicle of error. It is recommended to conduct a hardware-in-loop analysis to make certain the algorithms developed in this study perform as expected in a dynamic operation.
7

Analysis and Modeling of One-Way Network Delay Variations

Al-Omari, Huthaifa Abdelhameed 03 August 2009 (has links)
No description available.
8

Factors associated with patient, and diagnostic delays in Chinese TB patients: a systematic review and meta-analysis

Li, Ying, Ehiri, John, Tang, Shenglan, Li, Daikun, Bian, Yongqiao, Lin, Hui, Marshall, Caitlin, Cao, Jia January 2013 (has links)
BACKGROUND:Delay in seeking care is a major impediment to effective management of tuberculosis (TB) in China. To elucidate factors that underpin patient and diagnostic delays in TB management, we conducted a systematic review and meta-analysis of factors that are associated with delays in TB care-seeking and diagnosis in the country.METHODS:This review was prepared following standard procedures of the Cochrane Collaboration and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement and checklist. Relevant studies published up to November 2012 were identified from three major international and Chinese literature databases: Medline/PubMed, EMBASE and CNKI (China National Knowledge Infrastructure).RESULTS:We included 29 studies involving 38,947 patients from 17 provinces in China. Qualitative analysis showed that key individual level determinants of delays included socio-demographic and economic factors, mostly poverty, rural residence, lack of health insurance, lower educational attainment, stigma and poor knowledge of TB. Health facility determinants included limited availability of resources to perform prompt diagnosis, lack of qualified health workers and geographical barriers.Quantitative meta-analysis indicated that living in rural areas was a risk factor for patient delays (pooled odds ratio (OR) (95% confidence interval (CI)): 1.79 (1.62, 1.98)) and diagnostic delays (pooled OR (95% CI): 1.40 (1.23, 1.59)). Female patients had higher risk of patient delay (pooled OR (95% CI): 1.94 (1.13, 3.33)). Low educational attainment (primary school and below) was also a risk factor for patient delay (pooled OR (95% CI): 2.14 (1.03, 4.47)). The practice of seeking care first from Traditional Chinese Medicine (TMC) providers was also identified as a risk factor for diagnostic delay (pooled OR (95% CI): 5.75 (3.03, 10.94)).CONCLUSION:Patient and diagnostic delays in TB care are mediated by individual and health facility factors. Population-based interventions that seek to reduce TB stigma and raise awareness about the benefits of early diagnosis and prompt treatment are needed. Policies that remove patients' financial barriers in access to TB care, and integration of the informal care sector into TB control in urban and rural settings are central factors in TB control.
9

Facilitatory neural dynamics for predictive extrapolation

Lim, Hee Jin 02 June 2009 (has links)
Neural conduction delay is a serious issue for organisms that need to act in real time. Perceptual phenomena such as the flash-lag effect (FLE, where the position of a moving object is perceived to be ahead of a brief flash when they are actually colocalized) suggest that the nervous system may perform extrapolation to compensate for delay. However, the precise neural mechanism for extrapolation has not been fully investigated. The main hypothesis of this dissertation is that facilitating synapses, with their dynamic sensitivity to the rate of change in the input, can serve as a neural basis for extrapolation. To test this hypothesis, computational and biologically inspired models are proposed in this dissertation. (1) The facilitatory activation model (FAM) was derived and tested in the motion FLE domain, showing that FAM with smoothing can account for human data. (2) FAM was given a neurophysiological ground by incorporating a spike-based model of facilitating synapses. The spike-based FAM was tested in the luminance FLE domain, successfully explaining extrapolation in both increasing and decreasing luminance conditions. Also, inhibitory backward masking was suggested as a potential cellular mechanism accounting for the smoothing effect. (3) The spike-based FAM was extended by combining it with spike-timing-dependent plasticity (STDP), which allows facilitation to go across multiple neurons. Through STDP, facilitation can selectively propagate to a specific direction, which enables the multi-neuron FAM to express behavior consistent with orientation FLE. (4) FAM was applied to a modified 2D pole-balancing problem to test whether the biologically inspired delay compensation model can be utilized in engineering domains. Experimental results suggest that facilitating activity greatly enhances real time control performance under various forms of input delay as well as under increasing delay and input blank-out conditions. The main contribution of this dissertation is that it shows an intimate link between the organism-level problem of delay compensation, perceptual phenomenon of FLE, computational function of extrapolation, and neurophysiological mechanisms of facilitating synapses (and STDP). The results are expected to shed new light on real-time and predictive processing in the brain, and help understand specific neural processes such as facilitating synapses.
10

Examining the pathway to diagnosis and treatment of lymphoma in Manitoba: patient and system factors resulting in delay

Skrabek, Pamela 05 January 2017 (has links)
The province of Manitoba has set a goal of reducing time from suspicion of cancer to treatment to a target of sixty days. To attain this goal, a baseline understanding of current time intervals is required. This study examined system, diagnostic and treatment delay in adult patients (> 17) diagnosed with Lymphomas from 2005 to 2010 using administrative data (Manitoba Cancer Registry, Manitoba Health billing data and Hospital Abstract data) and a chart review of a random subset of patients. A triangulated data approach was used to identify suspicion of lymphoma and milestones in the patient journey and to measure delays in diagnosis and treatment. Using an iterative consultative process, an algorithm was built to identify index events likely related to subsequent lymphoma diagnosis. Then, claims data was searched for a referring provider for each index event. The last visit with a referring provider, prior to the first index event, was selected as date of high suspicion. The study found that 14.8% of patients met the provincial target of less than sixty days from suspicion to treatment. Median time from high suspicion to treatment, referred to as system delay, was 128 days and the median time from diagnosis to treatment was 41 days. Time to diagnosis accounted for two thirds of system delay. In conclusion, this study demonstrated the merit of a triangulated approach. As well the clinical pathway developed and the target timelines for milestones have operational value and can be used to direct process improvements to shorten delays for future patients. / February 2017

Page generated in 0.0269 seconds