Increasing energy costs and the need to conserve energy compounded with low mineral prices have prompted some Canadian mines especially potash producers, to examine their operations and identify potential saving methods. Re-using or recirculating a fraction of ventilating air may enable these mines to reduce winter heating costs. Gas and dust concentrations were monitored in the intake and exhaust airways to assess the potential for recirculating exhaust air. The results indicate that the mine pollutant concentrations in potash mines are low and stable. Trial recirculation experiments returning 20 - 47% exhaust air into the fresh air airway did not cause significant increases in mixed intake pollutant levels. Two types of recirculation systems - namely variable and fixed quantity - are developed. Detailed designs of recirculation systems for Central Canada Potash of Noranda Minerals Inc. and Rocanville Division, Potash Corporation of Saskatchewan are discussed and recommendations made for the selection and positioning of on-line monitoring, control and telemetry systems. A controlled recirculation system conceptual design for the H-W mine is given. The economic payback periods for systems proposed for Rocanville Division and CCP are 2 and 3 years respectively. Recirculation percentages of 30%, 64.4% and 23% are feasible for CCP, Rocanville Division and the H-W mine. The recirculation percentages for the proposed systems were determined using Air Quality Index criteria. Dust deposition studies conducted at CCP in return airways indicate that 65% of dust by weight is deposited within a distance of 550 metres from the face. In terms of dust and other contaminant conditions in the return airways, it can be concluded that there is potential for use of recirculation in the face area. Guidelines for recirculation systems in gassy and dusty mines are developed. The main features for these recirculation system design guidelines are safety, economic gain, and system performance. The author's attribution to ventilation is in the use of controlled recirculation to reduce winter heating costs and increase underground airflow, also the guidelines developed for recirculation in gassy and dusty mines. The overall conclusion is that controlled recirculation is a practical method of reducing winter heating cost and/or increasing mine airflows. The financial potential and technology to implement a working system exist. / Applied Science, Faculty of / Mining Engineering, Keevil Institute of / Graduate

Spirituality in the discipline of nursing has gained popularity over the past two decades. National and provincial nursing associations and colleges expect nurses to be educated in providing spiritual health assessments and interventions in order to provide holistic nursing care. There is a paucity of research in the nursing literature on the meaning of spirituality from the perspectives of individuals who experience chronic mental illness, specifically schizophrenia. Spirituality remains an elusive construct, challenging psychiatric nurse educators, researchers and practitioners in the development of nursing curricula to guide psychiatric nursing practice. The focus of this research study was to develop a substantive theory about the experience of spirituality among individuals living with schizophrenia using grounded theory methodology in the tradition of Glaser and Strauss (1967). Forty semi-structured interviews and four focus groups were conducted with 20 participants who self-reported to be diagnosed with schizophrenia. Findings: The substantive theory "spirituality as connection" indicates that spirituality for persons living with schizophrenia involves a dialectical process in which one strives to be connected to one's spiritual self (body-mind-spirit), significant others (family, friends, G o d / Higher Power, health care professionals), community (others living with a mental illness, others who are well, a faith community, the community in which participants lived), and nature, while at the same time experiencing situations and incidents that promote disconnection from these sub-themes. Strategies used by participants to achieve connection included: taking prescribed atypical anti-psychotic medications, maintaining their health and a healthy lifestyle, use of prayer / meditation, caring for self and others, and engaging in creative activities that added meaning to their life experiences. Among the 17 factors contributing to connection, exemplars are: reconnecting with one's spirit through prayer and meditation, attending drop-in centres for persons living with a mental illness, and walking / hiking in nature. Outcomes include feeling peaceful, love, contentment, being accepted and nurtured by others. Among the 14 factors contributing to disconnection, exemplars are: the effect of the illness on relationships with other people, the stigma of being in a psychiatric ward, being unemployed, and taking typical antipsychotic medications. Outcomes include feeling powerlessness, isolation, rejection and alienation. / Education, Faculty of / Curriculum and Pedagogy (EDCP), Department of / Graduate

Magister Artium - MA / Solid waste management in South Africa has been focussing on the technical issues of waste disposal with little attention paid to the social and economic aspects of households. It is important to find out the impact of the attitude and perception of households on solid waste management, especially in low-income areas to be able to deal with the deplorabe domestic solid waste management in such areas. The quantity of solid waste generated in low-income areas is often assumed to be less than the solid waste generated in high-income neighbourhoods. In most of the townships of low-income households in Cape Town, the residents live next to mountains of solid waste which is not the case in middle and high income areas. This clearly has a negative effect on the environment and human health. Tafelsig is one of the low-income Cape Flats townships where the open spaces and green areas are dumping areas. The small yard that people own is often unclean. The aim of the study was to examine how households residing in the low-income neighbourhood (Tafelsig, Mitchell's Plain) view domestic solid waste and its management. The study explored the perceptions, attitudes and behaviour of these households towards the production and management of sold waste. Issues relating to the degradation of their environment and to solid waste mismanagement were also examined. / South Africa

Thesis (MPH.) -- University of Limpopo, 2016. / Introduction: Annually, hundred thousands of people worldwide die as a result of second hand smoke (SHS) exposure. There is no safe exposure level to SHS yet in Bulawayo, smokers have been observed smoking without restraint thus exposing non-smokers to SHS. The purpose of this study was to establish the prevalence and contributing factors of SHS exposure among adults in Bulawayo, Zimbabwe. Methods: A cross sectional study was conducted and participants were randomly selected from residents who visited the 13 municipal revenue halls. A structured questionnaire was used to collect data from respondents. Descriptive and multivariate logistic regression analyses were performed. Results: Home SHS exposure prevalence was 22% and females were 2.11 times more likely than males to be exposed at home. Prevalence of SHS exposure in public transportation, health facilities, educational and food premises was 40.9%, 26.3%, 42,9% and 36.8% respectively. Conclusion: SHS exposure in Bulawayo was high and there is need to reduce SHS exposure to non-smoking adults. Keywords: Second hand smoke (SHS), Bulawayo, Prevalence, Exposure, Adult

No description available.

Public health and social policies are often debated, designed, and adopted without implementation, sustainability, or equity in mind, which can generate profound uncertainty about how to equitably deliver them initially and over time. Although sustainability and equity considerations are sometimes considered in post-hoc policy analysis and evaluation, little is known about how to plan for and track planned and unplanned adaptations to policy implementation, as well as the ways that key sustainability factors and strategies can relate to the equitable delivery or relative effectiveness of policies on the ground and in community settings. The purpose of this dissertation was to explore the long-term sustainability and equity of tobacco control policies and programs in New York City to understand and contextualize their limited reach and impact on persistent smoking and tobacco-related health disparities in underserved Asian American communities. The specific aims were to: 1) conceptually specify an operational definition of policy sustainability and its key dimensions, including health equity, and to refine this using a mixed methods single case study of tobacco policies in New York City; 2) use the case study approach to describe the extent to which tobacco policies have been sustained and adapted in New York City; and 3) to use the case study to identify key multi-level factors that influence the long-term sustainability and equity of tobacco policies in New York City. Using a single, in-depth, convergent-parallel mixed methods case study design, data were collected, analyzed, and integrated across five key primary and secondary sources: 1) Policymaking documents – text of key tobacco bills and statutes, as well as transcripts from when they were first proposed, amended, debated, and adopted; 2) Local newspaper coverage – articles from a database of 29 major newspapers in New York State on the policies and their impacts on communities and businesses over time; 3) Key informant interviews – conducted with community members and community leaders at local health and advocacy organizations in New York City that primarily serve Asian American and immigrant communities (n = 21); 4) Direct observation periods – conducted within and around the health and advocacy organizations, as well as in majority Asian neighborhoods and Asian ethnic enclaves (n = 15); and 5) the New York City Community Health Survey (2012-2017) – conducted annually by the New York City Department of Health and Mental Hygiene. The integrated study findings point to the importance of understanding policy sustainability not as a static end goal, but rather as a dynamic set of processes and outcomes that impact health and health equity. Findings from this case study clustered across three key themes: 1) since the initial adoption of comprehensive local tobacco control measures in New York City in 2002, broad “one-size-fits-all” approaches to policy implementation and monitoring have been sustained, which have had and continue to have limited reach and impact within underserved Asian American and immigrant communities; 2) two delayed adaptation efforts were made by policymakers during the sustainability phase, one in 2012 and another in 2018, were intended to improve on prior uneven implementation to better reach Chinese-speaking communities, with the 2018 adaptation demonstrating significant improvements from the 2012 effort; and 3) community-based organizations have played a direct role in functioning not just as key stakeholders but also as key implementers to ensure that tobacco and other health policies are reaching communities that the designated or official implementers cannot reach. This suggests the need for further study of unofficial implementers in implementation science – those who have not been formally designated as the ones responsible for ensuring that implementation takes place, but are still delivering implementation strategies to ensure adoption, integration, and sustainment. Overall, this case study points to the potential for policy sustainability research to advance health equity by identifying factors and mechanisms that can be improved to maximize and sustain the equitable reach and impact of social and public health policies. By focusing on dynamic contextual factors and sustainability as a set of processes and outcomes, the findings from this case study raise critical questions about the criteria typically used to evaluate whether policy interventions are deemed evidence-based and effective by asking: 1) effective for whom?; 2) based on what evidence?; and 3) what happens as dynamic populations and contexts change over time? These questions highlight how the tobacco control success story was largely constructed around broad population-wide implementation and benefits, while overlooking underserved Asian American communities who continue to disproportionately bear the brunt of smoking and tobacco-related health disparities in New York City.

The association between increased participation in physical activity (PA) and improvements in health is so well established that the promotion of regular participation in PA is a key public health priority. However, much remains to be explored about the dose-response relationship between PA and the many health benefits. To address this issue, there is a need to accurately measure PA across all population sub-groups. Finding a valid, reliable and sensitive measure of PA is essential for improving our understanding of PA-related disorders, for more clearly defining the dose-response relationship between the volume, intensity and pattern of PA and the associated health benefits, and to examine the effectiveness of interventions and public health initiatives. We conducted three exercise studies aimed at examining the associations between a novel indexof exercise volume and selected physiological and psychological outcomes. The first and second studies were secondary analyses of studies in which the validity of this index was assessed in two different exercise interventions: 12-weeks of moderate-intensity aerobic exercise and a 6-week high intensity interval training intervention. The third study was a prospective randomized controlled trial testing the feasibility and practicality of this index as applied to a specific population in an at-home exercise intervention. Taken as a whole, the results from the three studies indicate that the novel method of measuring exercise volume is promising for tracking some of the biological and psychological benefits that are associated with exercise. In these studies, this novel index of exercise volume was significantly associated with specific markers of biological adaptation to exercise training that are clinically meaningful. Further research is needed to replicate these findings in larger, diverse samples, and to broaden our understanding of how applications of this novel index can expand our ability to illuminate mechanisms whereby exercise might improve physical and mental health in research and in practice.

Ambient exposure to fine particulate matter (PM2.5) and ground-level ozone (O3) is identified as a leading risk factor for global disease burden. A major limitation to advancing our understanding of the cause and impacts of air pollution is the lack of observations with the spatial and temporal resolution needed to observe variability in emission, chemistry and population exposure. Satellite remote sensing, which fills a spatial gap in ground-based networks, is playing an increasingly important role in atmospheric chemistry. This thesis exploits satellite remote sensing observations to: (1) estimate human exposure to PM2.5 from remotely sensed aerosol optical properties; (2) identify the chemical regimes of surface O3 formation using satellite observations of O3 precursors. In the first part, we use a forward geophysical approach to derive PM2.5 distributions from satellite AOD at 1 km2 resolution over the northeastern US by applying relationships between PM2.5 and AOD simulated from a regional air quality model (CMAQ). We use multi-platform ground, airborne and radiosonde measurements to quantify multiple sources of uncertainties in the satellite-derived PM2.5. We find that uncertainties in satellite-derived PM2.5 are largely attributed to the varying relationship between PM2.5 and AOD that depends on the aerosol vertical distribution, speciation, aerosol optical properties and ambient relative humidity. To assess the value of remote sensing to improve PM2.5 exposure estimate, we compile multiple PM2.5 products that include information from remote sensing, ground-based observations and models. Evaluating these products using independent observations, we find the inclusion of satellite remote sensing improves the representativeness of surface PM2.5 mostly in the remote areas with sparse monitors. Due to the success of emission control, PM2.5-related mortality burden over NYS decreased by 67% from 8410 (95% confidence interval (CI): 4, 570 – 12, 400) deaths in 2002 to 2750 (95% CI: 700 – 5790) deaths in 2012. We estimate a 28% uncertainty in the state-level PM2.5 mortality burden due to the choice of PM2.5 products, but such uncertainty is much smaller than the uncertainty (130%) associated with the exposure-response function. The second part of the thesis focuses on ground-level O3. O3 production over urban areas is non-linearly dependent on the availability of its precursors: nitrogen oxides (NOx) and volatile organic compounds (VOCs). A major challenge in lowering ground-level O3 in urban areas is to determine the limiting species for O3 production (NOx-limited or VOC-limited). We use satellite observations of NO2 and HCHO to infer the relative abundance of NOx versus VOCs, thus to identify the O3 chemical regime. We first use a global chemical transport model (GEOS-Chem) to evaluate the uncertainties of using satellite-based HCHO/NO2 to infer O3 sensitivity to precursor emissions. Next, we directly connect this space-based indicator, retrieved consistently from three satellite instruments, to spatiotemporal variations in O3 recorded by on-the-ground monitors from 1996 to 2016. The nationwide emission reduction has led the O3 formation over U.S. urban areas to shift from VOC-limited to NOx-limited regime. Urban O3 monitors reveal trends consistent with this regime transition. Nonetheless, it is a major challenge for these retrievals to accurately depict day-to-day variability within urban cores. TROPOspheric Monitoring Instrument (TROPOMI) which launched in 2017, offers an unprecedented view to infer O3 chemistry at fine spatial and temporal scales. As an example, we use TROPOMI HCHO/NO2 to identify short-term changes in O3 sensitivity during the California Camp Fire. We find that the emissions from wildfires lead to NOx-saturated ozone formation near the fire source but NOx -limited conditions downwind. This thesis bridges basic research in atmospheric chemistry, which advances the state-of-science related to O3 and PM2.5 pollution from urban to global scales, and applied research in air quality management and public health, by quantifying the health benefits of emission control, and informs policymakers on which emission reductions to focus so as to maximize the cost-effectiveness of pollution controls. We show how space-based measurements can complement in situ networks and model simulations by providing information on the spatial heterogeneity and temporal evolution of PM2.5 exposure and O3 chemical regimes, which will lay the scientific foundation for interpreting future products retrieved from upcoming geostationary platforms.

Preterm birth is a key indicator of maternal and child health, affecting 1 in 10 deliveries in the United States (US) and contributing to long-term morbidity and healthcare costs. The COVID-19 pandemic and policies to mitigate the spread of infection may have indirectly impacted preterm birth, but the results of early epidemiological studies were mixed and declines were largely concentrated in high-income countries and populations. Moreover, while most studies focused on stress-related pathways associated with lockdown policies, healthcare disruptions may have also played a role. The goal of this dissertation was to investigate changes in preterm birth and healthcare disruptions related to the COVID-19 lockdown in a low-income population in the US. In the first aim, I conducted a systematic review of the literature on the pandemic and preterm birth, with a focus on studies that examine heterogeneity by income. In the second aim, New York State (NYS) Medicaid claims were used to examine changes in preterm birth rates during the state’s lockdown policy (NYS on PAUSE) using difference-in-difference methods. In the third aim, changes in preterm were further stratified into those that were spontaneous or medically induced, which may reflect a healthcare pathway. Weekly rates of healthcare utilization, antenatal surveillance, and maternal complications were also assessed using interrupted time series models to characterize healthcare disruptions over the course of the lockdown and across the state. Results from the systematic review documented the rapid growth in research on this topic since the beginning of pandemic. Among the 67 articles included, most reported some decline in preterm birth rates; however, there was large variation by country, methods of exposure assessment, and onset of delivery. Only seven studies focused on differences by individual income (or income proxies) and those that did were inconsistent. Results from Aim 2 suggested that NYS on PAUSE was associated with nearly a percentage point decline in preterm birth rates in the Medicaid-insured population, without a concomitant increase in stillbirth. Aim 3 demonstrated that the change in preterm was largely driven by declines in medically induced preterm. Interrupted time series models showed substantial, but time-limited, declines in pregnancy-related healthcare utilization at the beginning of NYS on PAUSE. Overall, the findings in this dissertation suggest there were modest declines in preterm birth during the COVID-19 lockdown among low-income women in NYS, particularly in medically induced preterm. Healthcare disruptions were common for Medicaid-insured women and may partially explain the reduction in preterm birth in this population. Future research is needed to determine whether this change was positive for some and negative for others, and what that might mean for efforts to improve pregnancy outcomes in the future.

Osteoarthritis (OA) is a progressive and complex joint disease that results from breakdown of articular cartilage and remodeling of underlying bone, which affects millions of Americans. While the expected lifetime of the load-bearing cartilage tissue should coincide with the lifespan of an individual, it has a limited ability to self-repair and the damage to the tissue can accumulate severely. One of the major challenges in OA treatment is its long asymptomatic period. Symptoms usually become noticeable when the disease is reaching advanced stages, and currently there is no effective intervention for early stages of OA. This may be due to lack of a reliable diagnostic method for detecting early OA. While OA is a degenerative joint disorder that may lead to gross cartilage loss and morphological damage to other joint tissues, a lot of subclinical, subtle biochemical changes occur in the early stages of OA progression. The degradation of collagen type II matrix in articular cartilage extracellular matrix (ECM) network may corelate with the progression of cartilage OA. During onset of OA, with the loss of collagen crosslinks, the collagen matrix in cartilage ECM becomes more disorganized and the cartilage can become susceptible to disorder and thus aggravate the degeneration. Raman spectroscopy has been utilized in studies of components of connective tissues, such as OA, and cartilage degradation. Although studies have demonstrated the potential of applying Raman for diagnosing cartilage degeneration, the analysis of Raman spectrum obtained from articular cartilage is rather complicated and so far there is no generally accepted quantitative analysis for diagnosing early stages of OA. The first stage of this doctoral study aims to extend the capability of Raman spectroscopy to quantitatively characterize collagen network in articular cartilage, to investigate the possible correlation with the degeneration of OA. The first part of this doctoral dissertation is focused on developing a novel, non-destructive, quantitative diagnostic modality, based on Raman spectroscopy that has potential to detect changes in biochemical composition of articular cartilage. The study is focused on the basic research associated with quantification of crosslink density and kinetics of the crosslinking process. A theoretical and computational framework for characterization of collagen crosslinks has been established and applied onto two models, 2-dimensional collagen type I thin films, and immature bovine, proteoglycan depleted, articular cartilage. Glutaraldehyde solution has been applied onto the model as a convenient method to introduce various levels of collagen crosslinks. Refractive error is a problem with focusing light accurately onto the retina due to the shape or other misfunctioning of the eye, rather than on the retina for the normal vision. The most common types of refractive errors are near-sightedness, far-sightedness, astigmatism, and presbyopia. Refractive errors have become a growing public health problem worldwide. Its incidence has doubled over the last 50 years in the United States and Europe. It is even more significant issue in some East Asian countries, where its prevalence reaches 70 to 90%. Most affected individuals use spectacles or contact lenses, which generally provides adequate refractive error correction. However, both are subject to limitations. Glasses do not work well in the rain and mist may form on them following changes in temperature or humidity. Contact lenses improve the field of vision and acuity, but many people find their presence on ocular surfaces intolerable. Over the last two to three decades, refractive surgery for the permanent correction of vision has thus emerged as an attractive choice for many patients. However, such a surgery is an invasive procedure that may compromise corneal structure, and postsurgical complications have been reported. In the second stage of this doctoral work, a novel, non-invasive femtosecond laser collagen crosslinks manipulation method is studied. This laser collagen crosslinking treatment is applied on corneal tissue for vision correction. Two examples of the laser treatment on an ex vivo porcine eyes model are proposed in the study: corneal flattening, which is used to correct refractive errors due to myopia, and corneal steepening, which is used to treat hyperopia. The effective refractive power is used to evaluate the effectiveness of the two different treatments. The depth of the crosslinked region in the cornea is assessed by two-photon autofluorescence (TPF) imaging. TPF imaging can be used to visualize changes induced in the cornea, because collagen is a primary extracellular source of nonlinear emissions. The safety of the proposed treatment methods is examined by haematoxylin and eosin (H&E) stained histological sections of corneas. The ex vivo porcine corneas are also cultured for one week after treatment, to determine whether crosslink density remains stable, and to check for degradation in the crosslinked layers of the stromal matrix, and further prove the safety of the proposed laser treatment method through the evaluation of cell viability after one week of treatment. An in vivo rabbit animal model, widely used as a model for the correction of refractive errors, is further utilized to demonstrate the stability and safety of the induced changes. The effective refractive power of live rabbits is assessed 24 h, seven days, and then weekly up to three months after the laser crosslinking treatment. The safety of the laser treatment is first evaluated by histology staining, and further confirmed by in vivo confocal laser scanning microscopy. This laser treatment approach could expand the pool of patients eligible for permanent vision correction, while simultaneously eliminating the adverse effects associated with current forms of surgery. Furthermore, the approach described is also suitable for the treatment of other disease for collagenous tissues. The last chapter of in this doctoral dissertation have discussed the results of applying this laser treatment techniques for the treatment of progressive OA. Finally, in a preliminary study, the proposed femtosecond laser treatment modality developed for corneal tissue has been applied onto articular cartilage towards slowing down or retarding progression of early osteoarthritis. We hypothesize that degradation of the articular cartilage extracellular matrix can be slowed down or reversed in the collagen network crosslinked with a femtosecond laser. We further theorize that the crosslinking mechanism introduced in the corneal tissue, which relies on laser ionization and dissociation of the tissue interstitial water to produce of refractive oxygen species, can increase crosslink density of collagen network in an articular cartilage. In the study, the treatment has been applied onto devitalized and live immature bovine cartilage explants, as well as cartilage plugs obtained from OA afflicted human cadaver joints. The preliminary results have shown that the proposed treatment has potential to enhance tissue mechanical properties, and increase wear resistance, an important factor in slowing down the progression of OA. Furthermore, preliminary imaging of live/dead stained tissue has shown that the laser treatment has minimal adverse effects up to two weeks after the laser irradiation.