背景: 香港和廣州市是華南兩大發達城市，都面臨著人口老化的嚴峻形勢。由於醫療水準的提高，癡呆成為一個非常嚴重的公共健康問題。由於缺乏有效的治療手段，早期發現和干預成為減少認知功能損害及癡呆發病的最有效的措施。研究怎樣保護長者的認知功能對於公眾健康具有越來越重要的意義。越來越多的證據表明休閒活動有益於認知功能。研究表明體育鍛煉，腦力活動以及社會活動有益於認知健康，可以減少癡呆發病的風險。然而由於概念上的差異和研究方法的不同，使得目前的研究結果很難進行比較。由於社會背景會顯著影響休閒活動的參與，研究社會背景怎樣影響休閒活動對於長者認知功能的作用具有重要的意義。香港和廣州為華南兩大城市，其人口種族，基因，健康狀況及人口學特徵相似。然而在過去的一百多年中，由於歷史發展的不同，兩城市有著不同的社會系統。以上這些因素對於研究不同設計背景下的認知功能的對照研究提供了方便。研究兩地認識休閒活動與認知功能的關係，有助於評價不同社會環境對於休閒活動影響認知功能的以及社會因素對認知功能的影響。 / 研究目的: 本研究對於兩地長者認知功能的特點以及休閒活動的參與情況進行了比較。研究的主要目的是評估休閒活動與認知功能的關係，以及兩個城市中休閒活動與認知功能的關係。 / 方法: 這是一個橫斷面研究。557名非癡呆住在社區的長者參與了研究，其中香港260名，廣州297名。兩組長者在年齡，性別以及教育程度上沒有差異。休閒活動分為體育活動，智力活動，社會活動以及消遣活動。休閒活動的參與通過三種方式進行評估：種類，次數以及每週參與的小時數。一組評估量表包括：簡短精神狀態量表，詞語記憶，延遲回憶，詞語流暢性測驗，連線測驗，數位劃消測驗及Stroop測驗，用於評估兩地長者的認知功能。 / 兩地長者的人口學特徵，認知功能以及休閒活動的參與進行了比較，多元線性回歸用於分析每一類休閒活動與認知功能的關係，同時控制可能的混雜因素包括年齡，性別，教育程度，職業，婚姻狀況，居住情況，吸煙、酒情況，慢性疾病以及精神狀態。分層回歸用於分析每類休閒活動與認知功能的關係，同時控制其他三類休閒活動以及與認知功能顯著相關的混雜因素。 / 結果: 多元回歸分析表明與家人居住在一起者休閒活動的總類較多 (p=0.01)，休閒活動的時間較長 (p=0.02)。协方差分析檢驗顯示除了每週看電視的時間 （p=0.07），香港長者參與的休閒活動在種類，次數以及每週參與的小時數都明顯多於廣州長者，差異具有顯著性。兩地長者的認知功能測驗的分數未見顯著差異。體育活動（腦-身體鍛煉及有氧鍛煉）的種類與延遲回憶及詞語分類測驗顯著相關。智力活動與所有的認知功能測驗顯著相關。社會活動與語詞回憶和詞語流暢性測驗顯著相關。休閒活動與語詞回憶及連線測驗顯著相關。 / 多元線性回歸分析了休閒活動與認知功能的關係的同時，控制了其他三類休閒活動以及與認知功能顯著相關的協變數。分析結果顯示智力活動的種類與簡易精神狀態量表，語詞回憶，延遲回憶，詞語流暢性測驗以及數位劃消測驗顯著相關 （p<0.001）。體育活動和社會活動與認知功能未見明顯相關。消遣活動的時間與連線測驗顯著相關 （p=0.01）。休閒活動與認知功能的相關性兩地未見明顯顯著差異。 / 結論: 香港的長者參與了較多的休閒活動，但是認知功能測驗的分數與廣州長者卻沒有顯著差別。結果可能與之前的研究結果相矛盾，即參與較多的休閒活動與良好的認知功能相關，這可能與兩地的社會人口學的差異相關。以前的研究證明晚年的婚姻狀態與癡呆或者認知功能的下降相關。未婚或者喪偶的長者罹患癡呆症或者認知功能下降的風險性較高。香港未婚或喪偶長者較廣州多，或許這可以解釋為什麼香港長者參與較多的休閒活動，但是認知功能測驗卻未明顯優於廣州長者。同時也表明，除了休閒活動，社會因素（婚姻及居住狀況）對認知功能也有影響。 / 我們的研究表明參與智力活動尤其是參與各種各樣的智力活動與長者良好的認知功能相關。智力活動與認知功能的相關性在兩地沒有顯著差別，表明智力活動可在不同的社會環境中用於保護長者的認知功能。其他三類的活動與認知功能未發現有顯著相關性，這可能與智力活動的混雜效應有關，也可能與各活動之間其構成成分的重疊有關。儘管這樣，休閒活動對於認知功能的保護作用扔值得進一步研究。 / Background: The two most developed cities in southern China, Hong Kong (HK) and Guangzhou (GZ), are facing rapid population aging. As a result of improvements in medical care, dementia has emerged as a crucial public health problem. With limited treatment options available, early detection and intervention are likely to be the most effective strategies to reduce subsequent impairments and morbidity. Research into the prevention of cognitive decline among older persons is crucial for public health. There is increasing evidence that participation in leisure activities has a favorable effect on cognitive function. Studies have reported that physical exercise, cognitive activity and social engagement are beneficial for cognitive health and may reduce the risk of dementia. However, interpretation of the available evidence is hampered by conceptual discrepancies and methodological variations. As the social context may significantly influence leisure activity participation, it is interesting to explore how social contexts play a role in modulating the effects of leisure activity on cognitive function in older adults. HK and GZ are two major cities in southern China, and they share very similar ethnic, genetic, health and demographic characteristics. However, owing to differences in historical development, the two cities have been run with different social systems over the past few decades. This provided a natural case-control experiment for studying the effect of the social context on cognition. Hence, this study examined the association between leisure activity participation and cognition in the two cities to evaluate the cognitive modulating effects of leisure activities in different social environments. / Objectives of the studies: The main study objectives were to compare the cognitive characteristics and leisure activity participation of the two groups; to examine the association between leisure activity participation and cognitive function and the specific associations in HK and GZ; and to explore the modulating effect of social factors on cognitive function. / Methodology: This was a cross-sectional study. Convenience sampling was used to recruit 557 participants aged 60 years and over without dementia. Of these, 260 were recruited in HK and 297 in GZ. The two groups were recruited with similar demographic characteristics (age, gender and education). Leisure activities were classified as physical, intellectual, social and recreational activities. Leisure activity participation was measured in terms of the total number and total hours of participation per week for each category of activities. A battery of cognitive tests including the Cantonese version of the Mini Mental State Exam (CMMSE), word list learning test, delayed recall test, Category Verbal Fluency Test (CVFT), trail making test, digit cancellation test and Stroop test were used to measure participants’ cognitive function. / Differences in the participants’ demographic characteristics, cognitive performances and leisure activity participation were computed. A multiple linear regression of cognitive performance on leisure activity was performed, while controlling for other categories of activities and potential confounders that were significantly associated with cognitive function. / Results: The multiple linear regression revealed that living arrangement had a significant positive association with the total number of leisure activities (p=0.01) and total hours of leisure activity participation (p=0.02). Analysis of covariance showed that participants in HK participated in more leisure activities than those in GZ, as measured by the total number of subtypes and hours per week, except total hours of recreational activities per week (p=0.07). No significant differences were found between the cognitive performances of the older persons in the two cities. Pearson’s correlation and x² tests were performed to identify the leisure activities and potential confounders that were significantly correlated with cognitive performance. The total number and total hours of intellectual activity were significantly correlated with CMMSE scores (p<0.001 and p<0.001).The total number of subtypes and total hours per week of intellectual activity (p<0.001 and p<0.001), social activity (p<0.001 and p<0.01) and recreational activity (p<0.001 and p<0.01) were significantly correlated with the word list learning test. The total number of physical activities (p<0.01), total number of intellectual activities (p<0.001) and total hours of intellectual activity (p<0.01) were significantly correlated with the delayed recall test. The total number of physical and intellectual activities (p<0.01 and p<0.001), and total hours of intellectual and social activity (p<0.01 and p<0.001) were correlated with the CVFT. The total number of intellectual activities (p<0.01)and total hours of recreational activity (p<0.01) were significantly correlated with the trail making test (p<0.001). The total number and total hours of intellectual activity were significantly correlated with the digit cancellation test (p<0.001 and p<0.001). The total number and total hours of intellectual activity were significantly correlation with the Stroop test (p<0.01 and p<0.001). / Multiple linear regression using the enter method was conducted to measure the association between leisure activities and cognitive performance. The results showed that the total number of intellectual activities was significantly associated with better performance on cognitive tests, including the CMMSE (p<0.001), word list learning test (p<0.001), delayed recall test (p<0.001), CVFT (p<0.001) and digit cancellation test (p=0.01). Total hours of recreational activity was significantly associated with the trail making test (p=0.01). Multiple linear regression using the enter method also revealed that marital status was significantly associated with the CMMSE (p=0.002), word list learning test (p=0.003), delayed recall test (p=0.002), trail making test (p<0.001) and digit cancellation test (p=0.01). / Conclusions: HK participants participated in more leisure activities than GZ participants. However, HK participants did not show better cognitive performance than GZ participants. This finding appears to be inconsistent with previous studies that found that participation in more leisure activities predicted better cognitive functioning. This inconsistency might be explained by socio-demographic differences between the two cities. Some previous studies have found an association between late-life marital status and the risk of cognitive impairment. Older persons who were unmarried or widowed were at higher risk of dementia or cognitive decline. There were more unmarried or widowed participants among HK participants. The results indicate that in addition to leisure activities, social factors (marital or living status) might also contribute to the preservation of cognitive function among the elderly. / Our results underscore the significance of intellectual activity, especially participation in a variety of intellectual activities, in maintaining better cognitive functioning in older persons. Furthermore, a similar significant association between intellectual activity and cognitive function was found for participants in both HK and GZ, suggesting that the protective effect of intellectual activity could be generalized to different social environments. We failed to find significant associations between physical, social and recreational activities and cognitive function. However, the protective effect of leisure activity participation is recommended for further investigation in future studies. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Su, Xiufang. / Thesis (Ph.D.) Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves 88-94). / Abstracts also in Chinese; appendixes in Chinese.

Researchers have examined social relationships as a basic need, showing that being well integrated in a network of social ties is related to various positive health outcomes including reduced mortality and risk behavior (e.g. reduced alcohol consumption). Conversely, a lack of strong social ties is related to negative outcomes including depression, suicide, and substance use (Berkman & Syme, 1979; Durkheim, 1951; Sarason, Sarason, & Gurung, 2001). Loneliness, a negative affective experience resulting from relationship deficits, is related to similar health outcomes as social isolation including depression and problematic alcohol use (Cacioppo, Hawkley, Crawford et al., 2002). However, research to date examining loneliness and health behavior has predominantly employed cross-sectional measures (e.g. UCLA Loneliness Scale; Russell, Peplau, & Cutrona, 1980), therefore failing to capture more fluctuating experiences of and responses to loneliness which may signify maladaptive patterns of coping behavior (Hawkley, Burleson, Bernston, & Cacioppo, 2003; Shankur, McMunn, Banks, & Steptoe, 2011). The purpose of this present study was to examine responses to daily loneliness (i.e. social and solitary alcohol consumption) as a function of social integration and gender, through a secondary analysis of data collected in a larger daily process study. Results indicated that daytime loneliness predicted evening increases in solitary consumption and decreases in social consumption. Further, these within-person effects were influenced by gender and social integration. These findings provide a unique understanding of specific processes by which social relationships, or the perceived lack thereof, influence health and more specifically, mood-related health behavior.

Open burning of biomass and anthropogenic waste is a major source of aerosols at the biosphere-atmosphere interface, yet its impact on Earth’s climate and air quality is not fully understood due to the intricate feedbacks between the natural environment and human activities. Earth system models (ESMs) are a vital tool in the study of these aerosol-biosphere-atmosphere interactions. ESMs allow the estimation of radiative forcing and climate impacts in terms of changes to temperature and precipitation as well as the attribution to natural or anthropogenic drivers. To provide coherent results, however, ESMs require rigorous development and evaluation against observations. In my work I use the NASA-GISS ESM: ModelE. One of its strengths lie in its detailed aerosol schemes that include microphysics and thermodynamic partitioning, both necessary for the simulation of secondary inorganic aerosols. To overcome one of ModelE’s weaknesses, namely its lack of interactive biomass burning (BB) emissions, I developed pyre: ModelE’s interactive fire emissions module. pyrE is driven by flammability and cloud-to-ground lightning, both of which are calculated in ModelE, and anthropogenic ignition and regional suppression parameterizations, based on population density data. Notably, the interactive fire emissions are generated from the flaming phase in pyrE (fire count), rather than the scar left behind (burned area), which is commonly used in other interactive fire modules. The performance of pyrE was evaluated against MODIS satellite retrievals and GFED4s inventory, as well as simulations with prescribed emissions. Although the simulated fire count is bias-high compared to MODIS, simulated fire emissions are bias-low compared to GFED4s. However, the bias in total emissions does not propagate to atmospheric composition, as pyrE simulates aerosol optical depth just as well as a simulation with GFED4s prescribed emissions. Upon the development and evaluation of the fire-aerosol capabilities of ModelE, I have utilized it, with the EVA health model, to study the health impacts of outdoor smoke in 1950, 2015, and 2050. I find that chronic exposure to aerosols (PM2.5) is the main driver of premature deaths from smoke exposure, yet by 2050, acute exposure to ozone, formed downwind of BB smoke plumes, is projected to cause more premature deaths than exposure to PM2.5. I estimate the annual premature deaths from BB and waste burning (WB) smoke in 1950 to be ~41,000 and ~19,000, respectively, and in 2015 to be ~310,000 and ~840,000, respectively. By 2050 I project 390,000 and 1.5 million premature deaths from BB and WB respectively. In light of the growing impact of WB smoke exposure I identify the need to scale up viable waste management practices in regions of rapid population growth.

No description available.

The development of major commercial airports promotes the air transport industry and generates positive economic benefits to the airport and to its host economy. However, external costs are associated with these benefits. Any increase in aircraft movement causes negative environmental impacts, especially noise pollution. Governments have reduced aircraft noise levels at their sources, or introduced aircraft noise management strategies (ANMS); however the problems have never been satisfactorily resolved. This research aims at developing a better understanding of the impacts of aircraft noise on community health and well-being by exploring two core research questions: (1) ???Is health related quality of life worse in communities chronically exposed to aircraft noise than in communities not exposed????; and (2) ???Does long-term aircraft noise exposure associate with adult high blood pressure level via noise stress as a mediating factor????. The Sydney (Kingsford Smith) Airport has been selected as a case study. The health survey instruments have been developed and piloted, and then translated from English into Greek and Arabic. A postal self-administrative health survey (with follow-up letters) has been implemented in the areas surrounding Sydney Airport (called ???aircraft noise exposure group???) and in the matched control group. The total sample size was 1,500 with 47% response rate. This thesis has developed a ???new??? noise index (named Noise Gap Index, NGI) to describe and assess aircraft noise in such a way that is easily understood by the layperson. Factorial analysis of covariance revealed that ???Health related quality of life, in term of physical functioning, general health, vitality, and mental health, of community chronically exposed to high aircraft noise level were worse than the matched control area???. Binary logistic regression analysis found that ???Subjects (aged 15 ??? 87) who have been chronically exposed to high aircraft noise level have the odds of 2.61 of having chronic noise stress. In addition person who have chronic noise stress have the odds of 2.74 of having hypertension compared with those without chronic noise stress???. Finally, the robust hypotheses of effects of aircraft noise on community health and well-being for future experimental study were proposed.

From animal experimentation, and studies using in vitro models, there was evidence in the literature to suggest that dietary fibre may influence contractility and motility of the gastrointestinal tract and long chain (LC) n-3 polyunsaturated fatty acids (PUFAs) from marine sources may influence contractility of smooth muscle cells in blood vessels. The hypothesis of this thesis was that dietary fish oil and/or fibre influence the contractility of isolated intact sections of gut smooth muscle tissue from small animal models. Methodology was established to measure in vitro contractility of intact pieces of guinea pig ileum with the serosal side isolated from the lumen. It was demonstrated that four amino acid peptides from κ-casein (casoxins) applied to the lumen overcame morphine-induced inhibition of contraction. Using this established technology, the guinea pig was used to investigate the effects of dietary fibre and fish oil supplementation on gut in vitro contractility. In separate experiments, changes in sensitivity to electrically-driven and 8-iso-prostanglandin (PG)E₂-induced contractility were demonstrated for dietary fibre and fish oil. A modified, isolated gut super-perfusion system was then established for the rat to validate these findings. It was subsequently shown that LC n-3 PUFA from dietary fish oil significantly increased maximal contraction in response to the G-protein coupled receptor modulators, acetylcholine and the eicosanoids PGE₂, PGF₂α, 8-iso-PGE₂ and U-46619 in ileum but not colon, without changes in sensitivity (EC₅₀), when n-3 PUFA as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) had been incorporated to a similar degree into the gut total phospholipid membrane pool. It was further established that the spontaneously hypertensive rat (SHR) had a depressed prostanoid (PGE₂and PGF₂α) response in the gut that could be restored by dietary fish oil supplementation (5% w/w of total diet) in the ileum but not the colon. Importantly, the muscarinic response in the colon of the SHR was increased by fish oil supplementation with DHA likely to be the active agent. Dietary fish oil dose experiments deduced differential increases in response occurred at fish oil concentrations of 1% for muscarinic and 2.5% (w/w) for prostanoid stimulators of the ileum with no difference in receptor-independent KCl-induced depolarization-driven contractility. Studies combining high amylose resistant starch (HAMS, 10% w/w) and fish oil (10% w/w) fed to young rats demonstrated a low prostanoid response that was enhanced by dietary fish oil but not resistant starch. There was however, an interactive effect of the HAMS and fish oil noted for the muscarinic-mimetic, carbachol. Generally, resistant starch increased the large bowel short chain fatty acid pool with a subsequent lower pH. Binding studies determined that while the total muscarinic receptor binding properties of an isolated ileal membrane fraction were not affected in mature rats by dietary fish oil, young rats had a different order of muscarinic receptor subtype response with a rank order potency of M₃ > M₁ > M₂ compared to mature animals of M₃ > M₂ > M₁ with fish oil altering the sensitivity of the M₁ receptor subtype in isolated carbachol-precontracted ileal tissue. In conclusion, experiments using the guinea pig and rat gut models demonstrated that dietary fish oil supplementation, and to a lesser degree fibre, increased receptor-driven contractility in normal and compromised SHR ileum and colon. Further, changes in responsiveness were demonstrated in the developing rat gut prostanoid and muscarinic receptor populations that could be altered by dietary fish oil. Preliminary evidence suggested that fish oil as DHA may alter receptor-driven gut contractility by mechanisms involving smooth muscle calcium modulation. Defining the role that dietary fibre and fish oil, and other nutrients, play in normal and diseased states of bowel health such as inflammatory bowel disease (IBD), where contractility is compromised, are among the ongoing challenges. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1316907 / Thesis (Ph.D.) -- University of Adelaide, School of Molecular and Biomedical Science, 2008

Graduation date: 2002

Graduation date: 2004

Postmenopausat women on hormone replacement therapy (HRT) have been reported to be stronger when compared to women who are not using HRT. The first goal of this study was to investigate whether muscle morphology was altered in women who use HRT when compared to women who do not use HAT. In addition, this study examined the combined effects of a 6-month moderate-intensity strength training (ST) routine and HRT on the neuromuscular system of early postmenopausal women. Because not all the women completed the ST, this study was separated into two separate analyses, baseline (n=17; 7 HRT, 10 non-HRT) and training (n=14; 6 HRT, 8 non-HRT). ST consisted of two exercises (squat and dead lift), two days a week, for 6-months. Vastus lateralis muscle biopsies were taken at baseline and 6-months after exercise training. Biopsy samples were sectioned and analyzed histochemically for muscle fiber type and fiber cross-sectional area (CSA). In addition, voluntary knee extension strength was assessed at 30��/sec using an isokinetic dynamometer at these two time points. At baseline there were no significant differences in knee extensor strength between groups (HRT: 443 �� 121 N, non-HRT: 490 �� 106 N). Regardless of hormone status, Type I fibers were significantly larger (p=.005) in GSA (Type I=3705 �� 877��m��; Type II=2790 �� 756��m��). However, there were significantly more Type II fibers (p<.0001) (61.5 �� 7.9% of total) and consequently, Type II fibers occupied significantly more total fiber area p=.00l2) (Type I=45.3 �� 7.4%; Type II=54.7 �� 7.4%). No significant differences were found in the fiber type distributions of the HAT (37.9 �� 2.5% Type I, 62.1 �� 2.5% Type II) and non-HRT (38.9 �� 2.9% Type I, 61.1 �� 2.9% Type II) groups. There were no significant differences in fiber CSA of Type I fibers (HRT: 3615 �� 886 ��m��, non-HRT: 3769 �� 912 ��m��) or Type II fibers (HRT: 2770 �� 722 ��m��, non-HRT: 2849 �� 804 ��m��) obtained from the two groups. Six months of ST had no effect on the strength, fiber CSA, and fiber type distribution for HRT and non-HRT subjects. These results suggest that HRT does not alter muscle strength, fiber type distribution, and fiber CSA in early postmenopausal women. / Graduation date: 2003

With congressional passage of the BEACH Act in October of 2000, Coastal and Great Lakes states were mandated to assess coastal recreation waters for the application of ambient water quality standards. This research encompasses two components involved in applying the BEACH Act statues to Oregon. The first component was to select beach sites in Oregon. The second component involves applying bacterial recreational water standards to select Oregon beaches. Using the guidelines provided by the United States Environmental Protection Agency (EPA), this study develops a method to appraise Oregon marine recreational waters taking into account the following factors: use, available information, pollution threats, sanitary surveys, monitoring data, exposure considerations, economics, and development. In an effort to protect the public from swimming-associated illness attributable to microbial pollution, 24 beaches were identified in Oregon. Of these, 19 beaches were classified as tier 1, or high priority, and five sites were classified as medium priority, or tier 2. Future studies should be directed at ascertaining the beach lengths utilized by Oregon marine recreators since this is an important parameter in targeting bacterial monitoring. Ongoing monitoring of these 24 sites is warranted and new information could be used to update beach tier levels in Oregon. In the second phase of this study, bacterial monitoring data was used for comparison to recreational water quality standards. In October of 2002, the Oregon Department of Environmental Quality (ODEQ) sampled 26 beaches for enterococci and Escherichia coli (E. coli) densities. Of the water sampled from all 26 beach sites, nine exceeded s single sample maximum density of 104 enterococci colony forming units (cfu) per 100 milliLiters (mL). The Oregon beach with the highest exceedance occurred at Otter Rock's South Cove where the enterococci concentration was 4352 most probable number (MPN)/100 mL. A comparison of the 26 sampled beaches to ODEQ's estuarine E. coli standard of 406 organisms/100 mL resulted in two beaches with exceedances. Otter Rock at South Cove had the highest E. coli concentration at 1850 MPN/100 mL. Based on the limited data used in this study, should Oregon adopt the enterococci standard in lieu of the current ODEQ estuarine E. coli standard, more beaches will have exceedances of the recreational water standard. Additional bacterial monitoring is warranted to further characterize the nature and extent of the problem in Oregon. To protect the health of the marine recreating public, future Oregon marine water quality studies should delineate the "no swim" zone around creeks and model the impacts of rainfall on beach sites. / Graduation date: 2004