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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.
421

The influence of international aid allocations on mortality in Sub-Saharan Africa

Kellum, Chelsea Wilson 01 May 2010 (has links)
Does allocating large amounts of international aid specifically for fighting HIV/AIDS in Sub-Saharan Africa have an influence on mortality rates in this region? This paper explores the relationship between total Official Development Assistance and Official Development Assistance earmarked for HIV/AIDS with AIDS mortality and overall mortality within Sub-Saharan Africa between 2000 and 2006. There are no definitive findings from this study to conclude that the amount of any form of assistance aid has a positive or negative effect on mortality. The results suggest that focusing on establishing greater development and less government corruption would more effectively alleviate the high mortality rates in Sub-Saharan Africa than increasing funding for HIV/AIDS.
422

Effects of hypoxia and surface access on growth, mortality and behavior of juvenile guppies, Poecilia reticulata (Pisces : Poeciliidae)

Weber, Jean-Michel. January 1982 (has links)
No description available.
423

Outcomes of Percutaneous Coronary Intervention in Atrial Fibrillation Patients Presenting With Acute Myocardial Infarction: Analysis of Nationwide Inpatient Sample Database

Shanmugasundaram, Madhan, Paul, Timir, Hashemzadeh, Mehrtash, Movahed, Mohammad Reza 01 July 2020 (has links)
Background: Atrial fibrillation (AF) is common in patients presenting with myocardial infarction (MI). Percutaneous coronary intervention (PCI) has been shown to improve cardiovascular outcomes in MI. However, outcomes of PCI in AF patients presenting with MI remains largely unknown. Methods: We analyzed the Nationwide Inpatient Sample (NIS) database to calculate the age adjusted mortality rate for PCI in AF patients presenting with MI between 2002 and 2011, in adults over 40 years of age. This was then compared to the mortality rate for PCI in non-AF patients with MI. Specific ICD-9-CM codes were used to identify patients and outcomes. Results: Of 3,226,405 PCIs done during the study period, 472,609 (14.6%) PCIs were done on AF patients of which 137,870 PCIs were for MI. About 60% of these patients were male. Patients with AF were older (71.3 ± 10.6 years). Overall the number of PCIs shows a declining trend from 2002 to 2011, but for MI patients the number of PCIs appears stable over the years. The age adjusted in-hospital mortality following PCI in MI was significantly higher in AF group compared to the non-AF group (190.24 ± 17.21vs 109.08 ± 5.89 per 100,000; P < 0.01). This trend was seen during the entire study period. Conclusions: AF is prevalent in MI patients undergoing PCI. AF is associated with increased mortality following PCI for acute MI. AF is not a benign arrhythmia in MI patients and close attention is warranted in these patients to improve mortality.
424

Point of care ultrasound on ground ambulances: an investigation of mortality outcomes

Sluyter-Beltrao, Nicolas 13 February 2022 (has links)
Traumatic injury is a major burden in global healthcare systems, ranking among the leading causes of morbidity and mortality worldwide.1 Patients are first encountered at the pre-hospital scene by providers of varying levels of expertise, such as emergency medical technicians (EMTs) and paramedics, who provide temporizing measures while patients are transported to receiving hospitals to receive definitive care.2 Ultrasound is an ever-improving medical imaging modality which is increasingly portable, low cost, and provides diagnostic imaging rapidly without the harmful effects of radiation. The objective of this study is to determine whether introduction of prehospital ultrasound (PHUS) for use on ground ambulances by prehospital providers in order to improve choice of destination hospital and aid in needle thoracostomy for tension pneumothorax will have a positive impact on mortality rate of trauma patients in an urban EMS environment. In the proposed study, trauma patients in the city of Boston, Massachusetts receiving care from Boston Emergency Medical Services (EMS) prehospital providers will be recruited over a 12-month period with a minimum goal of 2,500 patients in total. Emergency responses coded as trauma by EMS dispatch will be randomized at a 1:1 ratio to either utilize PHUS or to refrain from utilizing PHUS. A z-test will be used to analyze primary outcome of 30-day mortality rate in patients who receive PHUS care as needed compared with patients who do not receive PHUS care. Study data will be collected directly from Boston EMS Electronic Medical Record (EMR). This study will be the first of its kind to randomize at the patient level, and the first to investigate a major clinical outcome of ultrasound in prehospital medical care: 30-day mortality. Point-of-care Ultrasound is an intriguing diagnostic modality that is becoming increasingly feasible in the prehospital environment, and may improve outcomes in trauma patients. Current studies provide convincing evidence for the diagnostic accuracy of these devices, especially in evaluating hemoperitoneum and pneumothorax. If an improvement in mortality rate of patients treated with prehospital ultrasound (PHUS) is demonstrated, this will be convincing evidence for the implementation of PHUS in ground ambulances and air medical services across the United States and worldwide.
425

a clinical ausit of selected predictors of mortality of patients admitted to Charlotte Maxeke Johannesburg academic hospital intensive care unit with human immunodeficiency virus and tuberculosis co-infection

Singh, Avani January 2019 (has links)
A research report submitted to the Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, in partial fulfillment of the requirements for the degree of Masters of Medicine. Johannesburg 2019 / Background: The high level of co-morbid TB/HIV cases with severe organ failure on presentation in South Africa, results in an increased number of ICU admissions often with a poor prognosis at presentation. In this study, the aim was to identify patients admitted with HIV/TB co-infection and calculate the APACHE II scores and SOFA scores for each patient. Predicted percentage mortality was compared with actual mortality. Predictors of mortality were further identified, as well as the benefit of initiating ARV treatment in patients who are ARV naive upon admission to ICU. Methods: A retrospective audit of consecutive cases over a 24 month period was completed. Patient demographics; CD 4 count; ARV treatment status; ICU and 30 day mortality; the APACHE II Score; SOFA scores and correlating predicted percentage mortality were documented. The survival of patients was assessed using Kaplan Meier survival curves, and a univariate analysis was performed to identify risk factors for mortality. Calculated predicted mortality was compared with actual mortality to validate each scoring system and infer which was the better tool. Results: Of 75 patients admitted with pulmonary (43 cases) or extra-pulmonary (32 cases) TB, 23 died in the ICU (mortality 30,7%), and a further 10 died in the first 30 days of hospitalisation (30 day mortality 44%). A survival analysis established ARV treatment and CD 4 counts greater than 50 cells/mm3 were associated with a higher survival rate at any point of the analysis. In the entire study period, only 2 patients were initiated on ARV therapy during their ICU stay, 1 survived to discharge and 1 died in ICU. The APACHE II Predicted Mortality was within the 95% Confidence Intervals for all groups while the SOFA score was outside the upper bound limit of the 95% confidence intervals of actual mortality for those patients taking ARV treatment (52%, 95% CI 43,1% - 59,5% vs actual mortality 30%, 95% CI 17,7% - 46,1%), those with a CD 4 count of more than 50 (53,5% 95% CI 45,4% - 60,6% vs actual mortality 34%, 95% CI 22,1% - 48,4%) and female patients (51,2%, 95% CI 41,6% - 58,1% vs actual mortality 35,1%, 95% CI 21,4% - 50,4%). Conclusion: The study found that both the APACHE II and SOFA scoring systems were both statistically significant in prognosticating mortality in the study population. The APACHE II scoring system however showed a slightly improved prognostication in specific cohorts who had improved survival. It was also confirmed that patients with a CD 4 count of more than 50 cells/mm3, and those on ARV therapy had a statistically significant improved mortality. Further studies reviewing survival benefit of ARV initiation in ICU are warranted. ACKNOWLEDGEMENTS Supervisor: Prof GA Richards Co-Supervisor: Dr SHH Mohamadali Statistician: Mr MH Zondi Assistant - Data Collection: Ms S Madanlall / E.K. 2019
426

AN ASSESSMENT OF RECENT CHESTNUT OAK MORTALITY ACROSS THE EASTERN UNITED STATES WITH AN EMPHISIS ON INDIANA

Cameron David Dow (15354910) 01 May 2023 (has links)
<p>In 2016, chestnut oak (<em>Quercus prinus</em>) trees across southern Indiana began displaying symptoms of decline disease. In the years following, widespread patches of mortality appeared on slopes and along ridges, prompting the Indiana Department of Natural Resources (IDNR) to investigate. The IDNR noted the presence of <em>Phytophthora cinnamomi </em>on one diseased chestnut oak, leading to the initiation of this study. Our goals were to (1) determine if <em>P. cinnamomi </em>contributed to the widespread decline, (2) determine what site or stand variables were associated with higher rates decline, (3) examine the growth of declining trees prior to the onset of symptoms to determine if drought contributed to decline, and (4) use Forest Service Forest Inventory and Analysis (FIA) data to examine trends in regional chestnut oak mortality.</p> <p>From 2021-2022, we collected thirty fine root and soil samples from declining chestnut oak trees within Morgan-Monroe State Forest, Yellowwood State Forest, and the Hoosier National Forest. Throughout these forests, we established sampling plots within declining and healthy chestnut oak stands. In each plot we recorded site, stand, and tree level variables, then collected tree cores from two or three chestnut oak trees. Fine root samples were tested for the presence of <em>P. cinnamomi </em>at the Purdue Pathogen and Pest Diagnostic Laboratory (PPDL) in West Lafayette, Indiana.</p> <p>We used binomial linear regression to test for significant (α = 0.05) relationships between site and stand variables and decline, where a binary decline or no decline was used as the response variable. Both basal area increment (BAI) and ring width index (RWI) chronologies were built separately for healthy, declining, and dead chestnut oak trees. We used a paired t-test (α = 0.05) to test for significant differences in 10-year segments of BAI between the three chronologies. Finally, we used linear regression to test for significant (α = 0.05) effects of the standardized precipitation-evapotranspiration index (SPEI) in current and previous year growing seasons on RWI. Chestnut oak mortality volume across the eastern United States was calculated using the EVALIdator tool provided by USDA-FS FIA. Associations between chestnut oak mortality recorded by FIA and several climate and topographical variables were examined using a random forest classification.</p> <p>Out of thirty fine root samples, only one tested positive for the presence of <em>P. cinnamomi</em>, indicating that this decline was not associated with the pathogen. The analysis of site and stand variables revealed a greater chance of decline on east and northeastern facing slopes, with a slight increase in decline likelihood with increasing stand density. There was significantly lower BAI in dead and declining trees long before decline symptoms began, a pattern consistent with previous drought induced declines. We observed a significant relationship between RWI and SPEI in the early growing season (June and 3-month June SPEI) and throughout almost all of the prior year’s growing season (May, June, 3-month June, 3-month July, and 3-month August SPEI). Chestnut oak mortality volume across the eastern US steadily increased from 2006-2020, indicating a region-wide increase in mortality. Our random forest classification indicated the importance of increased precipitation and precipitation timing on chestnut oak mortality.</p> <p>Chestnut oak decline observed in southern Indiana was induced by a series of droughts in 2005, 2007, and 2012. The greater early life BAI of chestnut oak which were impacted by decline revealed that individuals which likely prioritized stem growth over root growth were predisposed to decline and mortality from these droughts. This prioritization could be brought on by genetic differences, favoring rapid height growth in developing even-aged stands, or by an abundance of moisture availability. Our FIA analysis of mortality revealed increased mortality volume across many states from 2006-2020, and that chestnut oak mortality may be related to greater precipitation compared to historic levels. Considering these results, we suspect that chestnut oak which have recently died or are currently declining are likely individuals which lack the root system to endure repeated drought.</p>
427

Trapping, Survival, and Probable Causes of Mortality of Chukar Partridge

Robinson, Aaron Clark 29 November 2007 (has links) (PDF)
We present an efficient and effective method for trapping chukars (Alectoris chukar) on artificial water sources. We compared a B-trap, a prairie chicken (Tympanuchus cupido) walk-in trap, a modified quail recall trap, and a newly designed Utah walk-in-funnel trap. Our Utah funnel trap outperformed standard techniques by more than 65%, and exceeded previous published results by 35%. Use of this method allows researchers and managers the ability to capture large numbers of Chukars relatively efficiently. With appropriate modifications this design is applicable for capturing a variety of bird species using small water developments. Chukars (Alectoris chukar) have been introduced throughout the world. Limited information regarding seasonal survival, causes of mortality, and other basic life history characteristics such as movements, home range, nesting and brood ecology, are available throughout their historical and introduced range of distribution. Lack of information is surprising because chukars have been introduced throughout the world and are popular with sport hunters. Survival estimates are particularly important for understanding population fluctuations which allows for adequate management. We evaluated the relationship of fall raptor migration, peak migration, reproductive period, and year effects on survival of chukars at 5 sites in western Utah. We also evaluated the probable cause of death for chukars with transmitters attached by examining evidence at kill sites. We captured and fitted 128 chukars with two different sized radio transmitters (99 females, 21 males, 8 sexes undetermined). Survival differed among study years where survival estimates showed significant (P< 0.01) differences between estimates in 2005 (Ψ = 0.03, 95% CI = 0.01 - 0.09), compared to 2006 (Ψ = 0.26, 95% CI = 0.18 - 0.38). Estimates showed that chukars were less likely to survive (P = 0.01) during the fall peak of raptor migration in 2006 (bi-monthly Ψ = 0.86, 95% CI = 0.74 - 0.93) than (base survival) outside this migration period and during the chukar reproductive period (bi-monthly Ψ = 0.97, 95% CI = 0.95 - 0.98). We documented 95 deaths; with 45% of causes unknown, avian predation accounted for 30%, mammals killed 1%, and hunters accounted for 7.6%. Our research suggested that predation on chukars was substantial during the fall raptor migratory period.
428

Intermetropolitan Comparisons of Mortality Patterns in Canada / 1976

Muryn, Jerry 04 1900 (has links)
<p> This paper is a descriptive analysis of differences in mortality rates among Canada's 23 Census Metropolitan Areas in 1976. · Life Table output focuses specifically on the life expectancies and standardized mortality rates as a means to identify CMA mortality differences. With mention to relevant cause-specific studies and use of regression analysis an attempt is made to shed some light on the identified mortality patterns. Major findings are (1) that mortality rate variation among CMAs reveals an east-west spatial arrangement - mortality rates in Atlantic, Quebec, and Northern Ontario CMAs are above the Canadian average while the mortality rates of Southern Ontario and Western CMAs are at or below the Canadian average; (2) that Victoria CMA is dominant among the CMAs in 1976 in terms of favourable mortality probability; (3) that male mortality rates are significantly higher than female mortality rates but tend to be positively related; (4) that health expenditures per capita have significant influence on health status but continued research is necessary to study and gain a fuller understanding of the effects of various explanatory variables on mortality. </p> / Thesis / Bachelor of Arts (BA)
429

A Comprehensive Analysis of Mortality due to COVID-19 in Long-Term Care / Mortality due to COVID-19 in Canadian Long-Term Care

Hothi, Harneet January 2022 (has links)
The long-term care (LTC) sector in Canada has experienced high numbers of COVID-19 deaths. However, there is a paucity of data on the impact of COVID-19 in LTC by different socio- demographic variables and in LTC homes within different regions. Additionally, the question remains as to how exactly and by how much the pandemic has impacted mortality in LTC in comparison to previous years’ mortality. Ranges for expected mortality by sex, province, and age, for the 2020-21 fiscal year were determined by creating forecasts and confidence intervals based on mortality trends in the preceding four fiscal years. These ranges were then compared to the actual mortality data in 2020-21. Comparisons between expected ranges and actual data were also conducted for the number of active residents, admissions, and discharges in LTC by sex, province, and age. Further, mortality ratios were created and studied by sex, province, age, and health region/authority/local health integration network. Overall, the number of deaths in LTC in Canada increased beyond the expected ranges in quarter one and three of 2020-21, and the patterns in death ratios were similar. Increases were exceptional in comparison to the peaks in deaths in previous years for specific variables, but not all variables. Most commonly, the number of active residents and admissions decreased in 2020-21 and the number of discharges from LTC did not change in quarter one and three and decreased in quarter two and four. However, importantly, these trends also varied across variables. This was the first study to comprehensively examine mortality due to COVID-19 in LTC overall, and by multiple socio- demographic variables while elucidating the complexity in the study of mortality in LTC. Further research is required to concretely understand mortality in LTC by different variables and regions. / Thesis / Master of Arts (MA) / This study examined mortality due to COVID-19 from April 2020 to March 2021 in Canadian long-term care (LTC) homes by sex, age, province, and health region. Ranges of predicted values for mortality were created from mortality data from previous years and then compared with actual mortality. The number of active residents, admissions, and discharges were also examined by sex, age, and province to factor for changes in the population at risk. Overall, mortality increased in some quarters (April-June 2020 and October-December 2020) but was not always exceptional, as similar mortality rates had been observed in the four years prior to the pandemic. Also, the increase in mortality was seen mostly among younger residents (65 to 85); mortality remaining stable for the 85+. Further research is still required to better understand mortality in LTC by regional characteristics.
430

An Investigation of Variables Associated with Mortality in a Broiler Complex in Mississippi

Johnson, Leslie B 03 May 2019 (has links)
A southern Mississippi broiler complex in an area of high poultry density experienced persistent lower livability and growth performance compared with company averages for the state. It was hypothesized that circulating Infectious Bronchitis Virus (IBV) challenge exacerbated by underlying Infectious Bursal Disease (IBD)-induced immune suppression was the primary contributor to reduced livability and live production performance on certain farms, and that disease challenges were most prevalent on farms in areas of high bird density. A retrospective analysis of data from a three-year period (March 2014 through March 2017) was designed to investigate the role of disease, settlement, geographic, and weather variables in broiler mortality. A database comprising diagnostic variables (processing-age ELISA titers for Infectious Bursal Disease (IBD), Infectious Bronchitis Virus (IBV), Newcastle Disease Virus (NDV), and Reovirus (REO)), settlement variables (downtime, age at processing, average weight at processing, week 1 mortality, genetic line, year, and broiler vaccination programs), geographic variables (number of commercial chicken farms and houses within 1 km, 5 km, 10 km and 15 km radii), and weather variables (average temperature, average heat index, and average humidity for the first 7 days and last 14 days of grow-out) was created and analyzed using univariable and multivariable statistical analyses. First-week mortality, processing age, average processing weight, genetic line, NDV/IBV vaccination program, and heat index in the last 14 days of the grow-out period were found to be significantly associated with flock mortality in this broiler complex (P <= 0.05). The results of this study should guide future management and disease control strategies aimed at reducing broiler mortality. Future studies with more diagnostic data are needed to further investigate the relative contribution of diseases to broiler flock mortality.

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