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Enhancing Spiritual Awareness Among Undergraduate Students: Improving Physiological Reactivity to and Recovery from Everyday StressorsAnderson, Micheline R. January 2021 (has links)
Chronic stress contributes to a global burden of disease that include mental illness, cardiovascular disease and early mortality. One pathway linking stress responses to health outcomes involves cardiovascular response to psychological stress. Specifically, vagal response as indexed by heart rate variability (HRV) can be used to examine autonomic processes, dysfunction of which can predict cardiovascular morbidity and mortality. The competitive academic climate on undergraduate campuses and insufficient time for recreation, rest and study, combined with inadequate coping skills can equate to consistent stressors that lead to subsequent stress and psychopathology among college students.
Research demonstrates that reduced HRV can be observed among students during exam time, whereas increased HRV is observed in times of rest, suggesting that academic stress contributes to real-time physiological changes that, when prolonged, can be pathogenic in nature. Interventions aimed at influencing these processes via relaxation or other mind-body approaches have shown that enhancing meta-cognitive skills and other coping strategies have proven helpful in both improving perceived stress and psychological distress as well as improving HRV when compared with controls.
This study investigates potential positive physiological effects of an eight-week Spiritual-Mind-Body (SMB) intervention, Awakened Awareness for Adolescents (AA-A), for undergraduate students. Specifically, we explore changes in HRV during resting, stress and recovery phases before and after the eight-week intervention. Additionally, we examine the association between change in self-report on measures of personal spirituality and psychological variables (pre-post AA-A), and changes across a host of HRV indices. Results include improvements in HRV recovery from stress and that a process of spiritual recovery is associated with these changes. SMB interventions that aim to improve spiritual and psychological functioning may promote psychophysiological resilience from stress.
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A Comparative study between the prevalence of MTHFR A1298C SNP and homocysteine metabolism in an elderly black South African populationDippenaar, Luzanne 08 1900 (has links)
M. Tech (Department of Biotechnology, Faculty of Applied and Computer Sciences) Vaal University of Technology. / Background: Cardiovascular diseases are one of the most common causes of death worldwide. This is not only a problem in developed countries, it is of major concern for public health in developing countries as well. Increased homocysteine is an independent risk factor for cardiovascular diseases. Nutritional deficiencies of folate, vitamin B6 and vitamin B12 are associated with hyperhomocysteinemia. MTHFR A1298C, a single nucleotide polymorphism, is similarly linked with higher concentrations of homocysteine. The aim of this study was to determine the prevalence of MTHFR A1298C in a black elderly population, along with folate, vitamin B6 and vitamin B12 and to evaluate the effect on homocysteine levels. Methodology: The research design was an observational cross-sectional study and was ethically approved. A total of 84 elderly who attend a day-care centre (also met inclusion criteria) were purposively selected. DNA was extracted and frozen on the day of blood collection. The MTHFR A1298C genotype was determined with real time PCR. Homocysteine, folate, vitamin B6 and vitamin B12 serum levels were detected with commercial assay kits. Results: Homocysteine was found to be elevated with a median of 17.78 µmol/L (interquartile range 13.98-21.03 µmol/L). Serum folate, vitamin B6 and vitamin B12 medians were in the normal range. Although, 5.95% and 22.62% of the population were deficient and possibly deficient for vitamin B12, respectively. MTHFR A1298C frequency was as follow: 89.29% (AA), 9.52% (AC) and 1.19% (CC), with no significant correlation (p>0.05) with homocysteine. Vitamin B12 correlated significantly with homocysteine levels. Conclusion: Vitamin B12 deficiency had an effect on homocysteine levels. Overall, nutritional deficiencies are not responsible for the hyperhomocysteinemia in this population. In conclusion from this study showed MTHFR A1298C frequency in black South Africans does not contribute to homocysteine as a risk factor for cardiovascular disease. Keywords: Cardiovascular disease, elderly, folate, homocysteine, MTHFR A1298C, vitamin B6, vitamin B12.
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Exposure to Nanomaterials Results in Alterations of Inflammatory and Atherosclerotic Signaling Pathways in the Coronary Vasculature of Wildtype RodentsDavis, Griffith M. 08 1900 (has links)
Cardiovascular disease (CVD) is the leading cause of death for people of most ethnicities on a global scale, and countless research efforts on the pathology of CVD has been well-characterized over the years. However, advancement in modern technologies, such as nanotechnology, has generated environmental and occupational health concerns within the scientific community. Current investigation of nanotoxicity calls into question the negative effects nanomaterials may invoke from their environmental, commercial, and therapeutic usage. As a result, further research is needed to investigate and characterize the toxicological implications associated with nanomaterial-exposure and CVD. We investigated the toxicity of multi-walled carbon nanotubes (MWCNT) and titanium dioxide (TiO2), which are two prominently used nanomaterials that have been previously linked to upregulation of inflammatory and atherogenic factors. However, the mechanistic pathways involved in these nanomaterials mediating detrimental effects on the heart and/or coronary vasculature have not yet been fully determined. Thus, we utilized two different routes of exposure in rodent models to assess alterations in proinflammatory and proatherogenic signaling pathways, which are represented in contrast throughout the dissertation. In our MWCNT study, we used C57Bl/6 mice exposed to MWCNTs (1 mg/m3) or filtered air (FA-Controls), via inhalation, for 6 hr/d for 14d. Conversely, intravenous TiO2 was administered to F344 male fisher rats, following 24h and 28d post-exposure to a single injection of TiO2-NPs (1 mg/kg), compared to control animals. MWCNT-exposed endpoints investigated the alterations in cholesterol transport, such as lectin-like oxidized low-density lipoprotein receptor (LOX)-1 and ATP-binding cassette transporter (ABCA)-1, inflammatory markers [tumor necrosis factor (TNF)-α], interleukin (IL)-1β/IL-6, nuclear-factor kappa-light-chain-enhancer of activated B cells (NF-κB) and signaling factors involved in activation of the pathway, as well as intracellular/vascular adhesion molecule(s) (VCAM-1, ICAM-1), and miRNAs (miR-221/-21/-1), associated with CVD, were analyzed in cardiac tissue and coronary vasculature. Cardiac fibrotic deposition, matrix-metalloproteinases (MMP)-2/9, and reactive oxygen species (ROS) were also assessed. TiO2-exposure endpoints also involved alterations on cholesterol transport proteins via LOX-1 and ABCA-1, factors of inflammation, namely intracellular macrophages and interleukin (IL)-1β, MMP-2/9 activity and protein expression, fibrotic deposition, and ROS generation were analyzed via quantitative detection or histologically in both cardiac tissue and coronary vasculature. Results from both studies found alterations in fibrotic deposition, upregulation in LOX-1 expression and MMP-2/9 activity, and ROS generation; with a concurrent decrease in ABCA-1 expression in cardiac tissue and coronary vasculature. Individually, MWCNT-exposed endpoints had shown induction of cardiac TNF-α, MMP-9, IκB Kinase (IKK)-α/β, and miR-221 mRNAs; as well as increased coronary expression of TNF-α and VCAM-1. TiO2 studies found increases in IL-1β and MMP-9 protein expression, as well as intracellular macrophage induction. Both studies also found, through pre-treatment of NADPH oxidase inhibitor, apocynin, resulted in attenuation of nanomaterial-exposure mediated ROS production; with nitric oxide synthase inhibitor, L-NNA, also showing attenuation, but only in our MWCNT-exposed inhalation study. The results from both studies have demonstrated, through different routes of administration, exposures, and rodent models; that exposure to nanomaterials can mediate signaling pathways involved in initiation and/or progression of CVD.
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Self-management strategies to prevent risk factors related to cardiovascular disease development at Ga-Molepo Area Clinics in the Limpopo Province, South AfricaKgatla, Mamoeng Nancy January 2022 (has links)
Thesis (Ph.D. (Health Sciences)) -- University of Limpopo, 2022 / Background: Cardio Vascular Diseases(CVD) are presently the main cause
of high mortality rate around the world. In sub-Saharan Africa, CVDs
contributes to about 13% of deaths, with 80% deaths being recorded from
developing countries. Behavioural and metabolic risk factors contribute to high
mortality rate related to development of CVD which self-management
strategies and practices could effectively prevent.
Objective: To explore and develop ―self-management strategies‖ to prevent
the development of CVD among patients living with chronic conditions at Ga Molepo Area clinics in the Limpopo Province, South Africa.
Methods: “A mixed method exploratory sequential design study was
conducted in four primary health care settings in a rural setting.‖ A semi structured one-on-one interviews were conducted with 43 patients selected by
non-probability homogenous purposive sampling for a qualitative strand.
Qualitative findings that was obtained with thematic ―Tesch‘s open coding
data analysis method guided the quantitative strand‖. A simple random
sampling was used to sample 347 respondents for the quantitative
strand.Descriptive statistics and chi-square were applied to analyze data from
the quantitative strand.
``Results: The qualitative results revealed that there is different self management strategies used by patients living with hypertension and
Diabetes Mellitus as risk factors of CVDs. The self-management strategies
include engaging in physical activity, eating a healthy balanced diet, drinking a
lot of water and adhering to treatment. The quantitative revealed majority of
participants(74%) perform mild exercises with 26% performing moderate
exercis.On the other hand 7% are having stress and depression and while
7% are smoking.``
Conclusions:The findings indicated that by adopting self-management
strategies could be an effective way of preventing the development of CVD
which complicates to hypertension and diabetic mellitus .Therefore are
encouraged to adhere to strategies adhere to treat,healthy diet and perform
mild exercises
Recommendations Hence, the government needs to appoint CHW
permanently to strengthen the guidelines on the prevention of CVD and also
the risk factors that put the communities at risk of developing CVD.
Communities need to adhere to preventative strategies ti order prevent CVD. / SPICES Project - (Scaling -up Packages of Interventions for CVD prevention
in Europe and sub-Saharan)
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The effect of leisure counseling upon selected attitudes of potential cardiac clientsHoeft, Thea M. January 1979 (has links)
The purpose of this study was to verify the efficiency of McDowell's leisure counseling model for potential use with cardiac rehabilitation and intervention programs in effecting leisure attitudes, work attitudes, work self-concept, leisure self-concept and leisure satisfaction.
To test the effectiveness of McDowell's model, an experimental research design, utilizing a pretest-posttest control group design, was used. The independent variable was counseling and the dependent variables, stated as alternative research hypotheses, were a positive effect on leisure self-concept, work self-concept, leisure attitudes, work attitudes and leisure satisfaction. Over a three month period, 24 adult subjects from an Adult Fitness Intervention Program volunteered for leisure counseling and were randomly assigned to one of two groups after which treatment was also randomly assigned. A test for homogeneity of regression revealed the subjects to be representative of the population on all variables except Work Self-Concept. In the study, a client typically was married, middle-aged, white-collar male worker.
To measure the dependent variables, five instruments designed to be used with McDowell's model were used. The data obtained from the leisure counseling sample was first subject to a test for homogeneity of regression after which hypotheses one, two, three and five, were subjected to an analysis of covariance.
The findings of the analysis of data allowed for the rejection of the null hypotheses and the acceptance of the research hypotheses for hypotheses two and five. For hypotheses one and three, the researcher failed to reject the null hypothesis, and rejected the research hypothesis. An interpretation of these findings suggested that leisure counseling using McDowell's model can affect one's leisure self-concept and leisure satisfaction.
From the study it was concluded that for the sample studied McDowell's leisure counseling model can be said to have positively increased the clients' leisure self-concept and leisure satisfaction on a short term basis. It was also concluded that leisure counseling as a component of cardiac rehabilitation/intervention programs using McDowell's model was said to be neither effective or ineffective for the sample studies. These results must account for the fact that the research methodology was not able to identify the possible reactive effect of the pretest. / Ed. D.
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Engineering Models of the Human Myocardium for the Investigation of Cardiac Injury and DiseaseNash, Trevor Ray January 2024 (has links)
Cardiovascular disease is the leading cause of death in the United States and the world. Progress in the development of new therapeutic strategies is hindered by shortcomings in our understanding of human myocardial pathophysiology and limitations in the ability of preclinical models to accurately predict successful clinical translation. The development of engineered models of the myocardium comprised of human cells derived from induced pluripotent stem cells has emerged as a promising strategy to overcome these problems.
This dissertation builds on this work by developing a new engineered cardiac tissue platform and then utilizing it to investigate three distinct myocardial pathologies: (1) genetic restrictive cardiomyopathy, (2) autoimmune mediated myocardial injury, and (3) myocardial ischemia and reperfusion injury. Results from these studies provide new insights into therapeutic strategies for the first two conditions and describe substantial progress towards the creation of an innovative model of the third.
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Particulate air pollution and effects on cardiovascular health in American Indian communitiesLi, Mengyuan January 2024 (has links)
Fine particulate matter (PM2.5) exposure is associated with increased risk of adverse cardiovascular health outcomes. Prior research shows that PM2.5 is disproportionately concentrated in communities of low socioeconomic status and with higher proportions of underrepresented ethnic and racial groups. However, little is known about the levels and trends in PM2.5 in American Indian (AI) communities. Prior work has estimated the risk of CVD outcomes from exposure to total PM2.5 and PM2.5 constituents in white, Black, Asian, and Hispanic populations; however, AI populations have been historically excluded from many of these studies. While certain behavioral and environmental CVD risk factors have been extensively studied in AI populations, the CVD health impacts of air pollution have not been previously characterized.
In Chapter 2, we aimed to compare PM2.5 concentrations in AI- vs. non-AI-populated counties over time (2000 – 2018) in the contiguous US. We used a multi-criteria approach to classify counties as AI- or non-AI-populated. We ran linear mixed-effects models to estimate the difference in county-wide annual PM2.5 concentrations from monitoring sites and well-validated prediction models (measured and modeled PM2.5, respectively) in AI- vs. non-AI-populated counties, adjusting for population density and median household income. We estimated whether differences in AI- vs. non-AI-populated counties varied over time using interaction terms with calendar year. On average, adjusted measured PM2.5 concentrations in AI-populated counties were 0.79 μg/m3 (95%CI: 0.33, 1.26) lower than in non-AI-populated counties. However, this association was not constant over time; while in 2000, adjusted concentrations in AI-populated counties were 1.83 μg/m3 (95%CI: 1.53, 2.13) lower, by 2018, they were 0.84 μg/m3 (95%CI: 0.53, 1.15) higher than in non-AI-populated counties. Over the study period, measured PM2.5 mean concentrations in AI-populated counties decreased by 2.49 vs. 5.18 μg/m3 in non-AI-populated counties. Results were similar for satellite-based, modeled PM2.5. This study highlights disparities in PM2.5 trends between AI- and non-AI-populated counties over time, underscoring the need to strengthen air pollution regulations in tribal territories and areas where AI populations live.
In Chapter 3, we further interrogate what components of PM2.5 could be contributing to the trends in total PM2.5. We estimated that adjusted concentrations of all six PM2.5 components in AI-populated counties were significantly lower than in non-AI-populated counties. However, component-specific trends varied over time. Sulfate and ammonium levels were significantly lower in AI- vs. non-AI-populated counties in 2000 but higher after 2011. Nitrate levels were consistently lower in AI- counties, while black carbon, organic matter, and soil levels showed inconsistent differences in AI- vs. non-AI-populated counties. This study highlights how differences in time trends of certain components by AI-populated county type, namely sulfate and ammonium, are driving steeper declines in total PM2.5 in non-AI vs. AI-populated counties, providing potential directives for air pollution regulations of key emissions sources on tribal and AI-populated lands.
In Chapter 4, we estimated the effects of long-term PM2.5 exposure on CVD incidence, CVD mortality, and all-cause mortality in the Strong Heart Study (SHS), a longitudinal cohort of American Indian adults enrolled from centers in Arizona, Oklahoma, and North Dakota and South Dakota. We followed 2,115 participants from 2000–2019. Adjusted hazard ratios (95%CI) per 1μg/m3 increase in PM2.5 with CVD incidence, CVD mortality, and all-cause mortality were 1.09 (0.91, 1.30), 1.11 (0.91, 1.36), and 1.10 (0.96, 1.25), respectively. Center-specific models identified positive associations between PM2.5 and incident CHD (2.24 (1.40, 3.56)) and CVD (1.55 (1.05, 2.31)) in Arizona, marginally positive association between PM2.5 and CVD mortality in Oklahoma (1.29 (0.99, 1.68)), and null associations in North Dakota and South Dakota. This study assesses PM2.5 exposure and cardiovascular health effects in American Indian communities—addressing a critical gap in the representation of evidence in air pollution regulation. Further research on underlying mechanisms driving the unique associations observed across regions is needed.
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Impact of vitamins B12, B6 and folate supplementation on cardiovascular risk markers in an elderly community of SharpevilleGrobler, Christina Johanna 09 1900 (has links)
Submitted in fulfillment of the requirements of the degree of Doctor of Technology: Health Sciences, Durban University of Technology, Durban, South Africa, 2015. / Background: In a vulnerable low-income group with a confirmed high risk of cardiovascular disease, like the elderly in the Sharpeville care centre, an acute intervention is needed in order to improve their health profile. Previous studies suggested homocysteine lowering by vitamin B12, B6 and folate supplementation. The effect of vitamin B12, B6 and folate supplementation on the inflammatory response, thrombotic risk, lipid profile, hypertension, risk of metabolic syndrome and homocysteine metabolism in an elderly, black South African population has never been reported.
Objectives: The main aim of this interventional study was to assess the effect of vitamins B12, B6 and folate supplementation at 200% RDA for six months on cardiovascular risk markers of an elderly semi-urbanised black South African community.
Design: This study was an experimental intervention non-equivalent control group study design in 104 purposively selected samples of all the elderly attending the day-care centre.
Setting and participants: A homogeneous group of respondents was included in the study. All subjects were equivalent in age (>60 years), race (black), unemployed/pensioners (socio-demographic) and 60 years and older attending a day care centre in Sharpeville, situated in the Vaal region, Gauteng, SA.
Measurements: The distinctiveness of this study lies in the broad panel of parameters evaluating the CVR in correlation with the increased nutritional intake of vitamin B6, B12 and folate. These included: weight, height, waist, serum cholesterol, high density lipoprotein (HDL), low-density lipoprotein (LDL), triglycerides, blood pressure, fibrinogen, high-sensitivity C-reactive protein (HS–CRP), homocysteine, vitamin B12, folate, glucose, insulin, adiponectin and fibronectin.
Results: A very high incidence (66.36%) of hyperhomocysteinaemia is present in the sample. The mean serum homocysteine level in hyperhomocysteinaemic individuals decreased statistically significantly from 25.00±8.00 umol/l to 18.80±12.00 umol/l after the intervention. The number of respondents with an increased homocysteine level decreased from 100% (baseline) to 67% (follow-up). The supplementation was beneficial (statistically significant changes) to the glucose levels, fibrinolytic status, vitamin B6 serum levels, fibronectin levels and haemopoeiesis (decreased macrocytosis) of all the individuals (regardless of their homocysteine status).
Conclusion: It is concluded that supplementation of vitamins B6, B12 and folate at 200% RDA for six months is an effective homocysteine-lowering approach as a strategy to reduce hyperhomocysteinaemia in an elderly population and thereby reduce cardiovascular risk (CVR). The supplementation intervention mentioned is not an effective multifactorial strategy to decrease CVR although beneficial effects were found with other CVR markers independent of homocysteine status.
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Screening for abnormal heart sounds and murmurs by implementing neural networksVisagie, Claude 03 1900 (has links)
Thesis (MScEng (Mechanical and Mechatronic Engineering))--University of Stellenbosch, 2007. / This thesis is concerned with the testing of an “auscultation jacket” as a means of recording
heart sounds and electrocardiography (ECG) data from patients. A classification system
based on Neural Networks, that is able to discriminate between normal and abnormal heart
sounds and murmurs, has also been developed . The classification system uses the recorded
data as training and testing data. This classification system is proposed to serve as an aid to
physicians in diagnosing patients with cardiac abnormalities. Seventeen normal participants
and 14 participants that suffer from valve-related heart disease have been recorded with the
jacket. The “auscultation jacket” shows great promise as a wearable health monitoring
aid for application in rural areas and in the telemedicine industry. The Neural Network
classification system is able to differentiate between normal and abnormal heart sounds
with a sensitivity of 85.7% and a specificity of 94.1%.
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Autonomous auscultation of the human heartBotha, J. S. F. 03 1900 (has links)
Thesis (MScEng (Mechanical and Mechatronic Engineering))--University of Stellenbosch, 2010. / ENGLISH ABSTRACT: The research presented in this thesis serves to provide a tool to autonomously
screen for cardiovascular disease in the rural areas of Africa. Vital information
thus obtained from patients can be communicated to advanced medical centres by
Telemedicine. Cardiovascular disease is then detected in its initial stages, which is
essential to its effective treatment. The system developed in this study uses recorded
heart sounds and electrocardiogram signals to distinguish between normal
and abnormal heart conditions. This system improves on standard diagnostic tools
in that it does not require cumbersome and expensive imaging equipment or a
highly trained operator.
Heart sound- and electrocardiogram signals from 62 volunteers were recorded
with the prototype Precordialcardiogram device as part of a clinical study to aid in
the development of the autonomous auscultation software and to screen patients
for cardiovascular disease. These volunteers consisted of 28 patients of Tygerberg
Hospital with cardiovascular disease and, for control purposes, 34 persons with
normal heart conditions.
The autonomous auscultation system developed during this study, interprets
data obtained with the Precordialcardiogram device to autonomously acquire a
normal or abnormal diagnosis. The system employs wavelet soft thresholding to
denoise the recorded signals, followed by the segmentation of heart sound by
identifying peaks in the electrocardiogram. Novel frequency spectral information
was extracted as features from the heart sounds, by means of ensemble empirical
mode decomposition and auto regressive modelling. These features proved to be
particularly significant and played a major role in the screening capability of the
system. New time domain based features were identified, established on the specific
characteristics of the various cardiovascular diseases encountered during the
study. These features were extracted via the energy ratios between different parts
of ventricular systole and diastole of each recorded cardiac cycle.
The respective features were classified to characterise typical heart diseases as
well as healthy hearts with an ensemble artificial neural network. Herein the decisions
of all the members were combined to obtain a final diagnosis. The performance
of the autonomous auscultation system used in concert with the Precordialcardiogram
device prototype, as determined through the leave-one-out crossvalidation
method, had a sensitivity rating of 82% and a specificity rating of 88%.
These results demonstrate the potential benefit of the Precordialcardiogram device
and the developed autonomous auscultation software in a Telemedicine environment. / AFRIKAANSE OPSOMMING: Hierdie tesis beskryf die navorsing van 'n outonome toetsing en sifting stelsel
vir kardiovaskulêre siektes in landelike dele van Afrika, vanwaar mediese inligting
per telefoon versend kan word. Die apparaat maak vroeë opsporing van kardiovaskulêre
siektes moontlik, wat essensieel is vir effektiewe behandeling daarvan
en ook die koste-effek van hierdie siektes verminder. In die huidige ontwikkelde
stelsel word normale sowel as abnormale hart-toestande getipeer met opnames
van hartklanke sowel as elektrokardiogram-seine. Voordele wat hierdie
stelsel bo standaard diagnostiese metodes het, sluit die hanteerbare formaat van
die hele apparaat sowel as die nie-noodsaaklikheid van duur beeldskeppende apparaat,
of hoogs opgeleide personeel.
Hartklank- en elektrokardiogramseine van 62 vrywilligers is met die prototipe
"Precordialcardiogram" apparaat opgeneem om by te dra tot die ontwikkeling van
die rekenaar sagteware vir die outonome auscultatsie stelsel en om die pasiëntsiftingsvermoë
daarvan te toets. Die vrywilligers het 28 pasiënte van Tygerberg
hospitaal met abnormale harttoestande ingesluit, sowel as ‘n kontrolegroep van 34
persone met normale harttoestande. Die outonome auskultasie-stelsel wat tot stand
gekom het deur hierdie ondersoek maak gebruik van “wavelet” sagte drempeling
om geraas uit die opgeneemde seine te verwyder. Daarna word die hartklanke gesegmenteer
deur die pieke van die elektrokardiogram te identifiseer.
Deur middel van "ensemble empirical mode decomposition" en outoregressiewe
modellering, is nuwe inligting aangaande die frekwensie spektra van
hartklanke, aanwysend van spesifieke harttoestande, verkry. Die beduidendheid
van hierdie eienskappe is bewys en het 'n belangrike rol in die siftingsvermoë van
die stelsel gespeel. Hierbenewens is nuwe tyd-gebaseerde eienskappe van die
onderskeie kardiovaskulêre siektes wat tydens die ondersoek bestudeer is, geïdentifiseer.
Hierdie eienskappe is geëien deur die energie-verhoudings tussen verskillende
dele van die ventrikulêre sistolie en diastolie van elke opgeneemde hartsiklus
te ontleed.
'n "Ensemble artificial neural network" is gebruik om die geïdentifiseerde eienskappe
van hartsiektes sowel as normale harttoestande, te klassifiseer. Hierin is
besluite van al die lede van die netwerk gekombineer, ten einde ‘n finale diagnose
te maak. Die klassifiseerder se geldigheid is kruis-bevestig deur middel van
die laat-een-uit kruisbevestigings-metode.
Deur middel van die kruis-bevestigingsmetode is die bedryfsvermoëns van die
outonome auskultasie-stelsel, toegerus met die "Precordialcardiogram" apparaat,
repektiewelik op 82% vir sensitiwiteit en 88% vir spesifisiteit vasgestel. Hierdie resultate demonstreer die benuttingspotensiaal van die apparaat in 'n Telemedisyne
omgewing.
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