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41.
This study measured the incidence of dental caries for one year and identified factors associated with the risk of caries in a sample of 156 elderly subjects. The subjects were examined at baseline and after one year to record the number of missing, filled and decayed teeth, to measure oral hygiene and flow of saliva, and to estimate the numbers of Streptococcus mutans and Lactobacilli cultured from samples of saliva. All subjects were interviewed on both occasions for information on their use of medications and dental services and on their ingestion of sugar. At baseline the elders had a mean of 19 natural teeth with 5 decayed surfaces (DS), 38 filled surfaces and a mean Plaque Index (PI) of 1. The independent group, on average, had more teeth and fillings but a lower PI and less caries. At the end of the year more than two-thirds (71%) of the 98 institutionalised subjects and over half (59%) of the 58 independent subjects had at least one new decayed/filled surface (DFS). The mean net DFS increment per subject was 4.6 and 2.0 respectively. Regression analyses on multivariate models identified caries at baseline, residence in long term care facilities, high numbers of Lactobacilli, poor oral hygiene and frequent sugar consumption as the variables contributing most significantly to the risk of caries in old age.  相似文献   
42.

1. 1. An investigation was carried out on 3 male and 4 female elderly people, from 65 to 78 years ol.d The first survey was made in August and September of 1990 (in summer) and the second in January and February of 1991 (in winter).

2. 2. Matters for investigation were human subjects and thermal environmental elements of houses which were recorded by a portable thermo-recorder and a vinyl resin globe thermometer. Dry bulb temperatures at a height of 0.1 and 1.2 m and wet bulb and globe temperatures at 1.2 m high were recorded in the living room, bedroom, toilet etc., the thermo-recorders which measured air and wet bulb temperatures were kept out of the sun.

3. 3. Data was recorded constantly for 7 days at 20 min intervals. Plans of houses and furniture arrangement which influence the thermal conditions were drawn from video recordings. Physical and psychological surveys of individuals were carried out over 2 days of daily life.

4. 4. Subjects carried the thermo-recorders (YM1, YM2) on their side. Rectal, back of hand, sole of foot and ambient temperatures were measured every 2 min and with thermistor sensors. At the same time, behaviour and clothes, assessment of thermal sensation, comfort sensation and sensation of estimated room temperature were reported.

5. 5. Thermal radiation was measured with thermographs during the winter. Human activity was recorded every minute for 33 h. This report is the result of surveys in summer and winter.

6. 6. The following results were obtained: (i) the air conditioning is used sometimes in the houses of the elderly; (ii) thermal sensation range reported is narrow; (iii) skin surface temperatures of the elderly are relatively high and their range of change is narrow, and the range of rectal temperature in a day is narrow; (iv) high activity and excessive heating cause a rise of rectal temperature and the rectal temperatures are lower at rest time.

Author Keywords: Thermal environment; residential thermal environments; the elderly  相似文献   

43.
A study was carried out in 1990 to guide the development of a protocol for assessing residential exposures of children to time-weighted-average (TWA) power-frequency magnetic fields. The principal goal of this dosimetry study was to determine whether area (i.e., spot and/or 24 h) measurements of power-frequency magnetic fields in the residences and in the schools and daycare centers of 29 children (4 months through 8 years of age) could be used to predict their measured personal 24-h exposures. TWA personal exposures, measured with AMEX-3D meters worn by subjects, were approximately log-normally distributed with both residential and nonresidential geometric means of 0.10 μT (1.0 mG). Between-subjects variability in residential personal exposure levels (geometric standard deviation of 2.4) was substantially greater than that observed for nonresidential personal exposure levels (1.4). The correlation between log-transformed residential and total personal exposure levels was 0.97. Time-weighted averages of the magnetic fields measured in children's bedrooms, family rooms, living rooms, and kitchens were highly correlated with residential personal exposure levels (r = 0.90). In general, magnetic field levels measured in schools and daycare centers attended by subjects were smaller and less variable than measured residential fields and were only weakly correlated with measured nonresidential personal exposures. The final measurement protocol, which will be used in a large US study examining the relationship between childhood leukemia and exposure to magnetic fields, contains the following elements: normal- and low-power spot magnetic field measurements in bedrooms occupied by subjects during the 5 years prior to the date of diagnosis for cases or the corresponding date for controls; spot measurements under normal and low power-usage conditions at the centers of the kitchen and the family room; 24-h magnetic-field recordings near subjects' beds; and wire coding using the Wertheimer-Leeper method. © 1994 Wiley-Liss, Inc.
  • 1 This article is a US Government work and, as such, is in the public domain in the United States of America.
  •   相似文献   
    44.
    Schembri A  Fiske J 《Gerodontology》2005,22(3):143-150
    Objectives: To establish oral health care practices, including the use of dental services, in the residential homes of Malta and Gozo by assessing the knowledge of home managers and assistance of care staff regarding residents’ oral health and hygiene; and evaluating the residents’ demand for dental treatment and residential home managers response to this demand. Subjects: A total population sample of licensed residential homes (38) in Malta and Gozo was used comprising all home managers in government (seven), church (20), and privately run (11) residential homes. Method: A 19‐question questionnaire was designed, piloted and sent to the home managers requesting them to report on the dental care provision for their elderly residents. The questionnaire was distributed by post, along with a reply‐paid envelope and an explanatory letter. A response deadline of 1 month was included. Results: An 87% response rate was achieved. Whilst the majority of home managers (64%) were aware of domiciliary dental services, there was no code of care practice for oral health. Routine dental check‐ups were not organised for residents of most homes. Although home staffs were generally given information about residents’ oral health and hygiene, the majority did not assist residents with oral hygiene. Home managers identified the following barriers to the use of dental services by residents: cost, communication problems with dental staff, journey to place of treatment, waiting time at the dental clinic, access to premises/clinic, lack of information on oral health and dental service availability, no one to accompany the person to the clinic, and health problems such as mobility, poor eyesight, hearing impairment and mental health status. Conclusion: Although most home managers appreciate the importance of oral health care for their residents, the residents still face many barriers to maintaining adequate oral health care and accessing dental services.  相似文献   
    45.
    Antarctic fishes and invertebrates, including Antarctic krill, are generally stenothermal, and it is necessary to maintain water temperature about 0°C to keep them in good condition. Because the effects of nitrifying bacteria are limited by the extremely low temperature of about 0°C, biological filtration does not keep up with the deterioration of water quality resulting from the excrement of animals and un-eaten food. It is therefore necessary to exchange seawater frequently in our present cold-water aquarium.

    We developed a new system at Port of Nagoya Public Aquarium (PNPA) that keeps Antarctic marine animals in good condition. The improved system increases the temperature of sea water to 10°C prior to biological filtration and thereby increases the effectiveness of the biological filter. The krill-rearing container was constructed inside the main tank so that the water flow inside the rearing container could be stopped. This avoids a rapid reduction of phytoplankton feed due to turnover of the seawater in the system while krill were fed. As a result of these improvements, long-term rearing, mass culture and reproduction of Antarctic krill are possible. We have exhibited Antarctic marine animals since the opening of PNPA in 1992, and we have exhibited Antarctic krill continuously since 1997. In this article, we detail the Antarctic krill breeding facilities at PNPA.  相似文献   
    46.
    王佳文  何萍  徐杰  丁森 《应用生态学报》2021,32(3):1129-1140
    水生态系统中宇宙指人工构建的河流、湖泊、湿地、海洋等水生态系统近自然模拟装置,可以控制一定的物理、化学要素和生境条件,开展生物群落响应研究。中宇宙实验可以弥补传统实验室小型装置模拟要素过于简单,而野外现实系统复杂不可控制和难以开展对比实验的局限。本文列举了当前国际上多个科研机构长期运行的水生态系统中宇宙,将其归纳为流水型中宇宙、围隔装置、陆基模拟池、移动式水槽4类,各类中宇宙一般包括物理-生物模拟系统、自动调控系统、监测分析系统、中央控制系统。近年来,我国水生态系统的研究逐渐从单一环境要素向生态系统整体转变,对中宇宙模拟实验的需求愈加迫切。建议我国水生态系统中宇宙建设应提高结构复杂性,并与野外现场监测相结合,共同支撑更大尺度系统的整体模拟。  相似文献   
    47.
    BackgroundCancer screening differs by rurality and racial residential segregation, but the relationship between these county-level characteristics is understudied. Understanding this relationship and its implications for cancer outcomes could inform interventions to decrease cancer disparities.MethodsWe linked county-level information from national data sources: 2008–2012 cancer incidence, late-stage incidence, and mortality rates (for breast, cervical, and colorectal cancer) from U.S. Cancer Statistics and the National Death Index; metropolitan status from U.S. Department of Agriculture; residential segregation derived from American Community Survey; and prevalence of cancer screening from National Cancer Institute’s Small Area Estimates. We used multivariable, sparse Poisson generalized linear mixed models to assess cancer incidence, late-stage incidence, and mortality rates by county-level characteristics, controlling for density of physicians and median household income.ResultsCancer incidence, late-stage incidence, and mortality rates were 6–18% lower in metropolitan counties for breast and colorectal cancer, and 2–4% lower in more segregated counties for breast and colorectal cancer. Generally, reductions in cancer associated with residential segregation were limited to non-metropolitan counties. Cancer incidence, late-stage incidence, and mortality rates were associated with screening, with rates for corresponding cancers that were 2–9% higher in areas with more breast and colorectal screening, but 2–15% lower in areas with more cervical screening.DiscussionLower cancer burden was observed in counties that were metropolitan and more segregated. Effect modification was observed by metropolitan status and county-level residential segregation, indicating that residential segregation may impact healthcare access differently in different county types. Additional studies are needed to inform interventions to reduce county-level disparities in cancer incidence, late-stage incidence, and mortality.  相似文献   
    48.
    The nature of the Bronze Age transition from the Umm an‐Nar (ca. 2700–2000 BC) to the Wadi Suq (ca. 2000–1300 BC) period in the Oman Peninsula has been highly debated by archaeologists, with some characterizing the latter as a time of cultural isolation, social collapse, and/or population replacement following the successful involvement of the area in widespread interregional exchange networks across Arabia and South Asia. The hypothesis that a substantial change in residential mobility, immigration, and diet took place in response to considerable societal changes as reflected by the archaeological record was tested using stable oxygen and carbon isotope analysis. Archaeological human dental enamel from individuals interred in six Umm an‐Nar (n = 100) and seven Wadi Suq (n = 16) communal tombs in the United Arab Emirates was used. Oxygen isotope data reveal largely homogeneous ratios indicative of a predominantly local population that acquired water from isotopically similar sources, although the presence of immigrants during both periods suggests that the region was not as isolated as previously held. Carbon isotope data exhibit a substantial temporal shift from an extremely varied to a more restricted diet, demonstrating that while considerable changes in subsistence strategies and social organization took place in the early second millennium BC, population continuity and sustained (although lessened) participation in pan‐Gulf trade systems best characterizes this regional transformation. Am J Phys Anthropol 152:353–369, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   
    49.
    Xiao JF  Wu JG  Shi CH 《遗传》2011,33(12):1409-1413
    先进的实验教学设施及开放水平是提升遗传学实验教学质量的重要保证。文章介绍了数码显微互动教学系统、细胞流线仪、近红外测定仪等一些先进仪器设备在遗传学实验教学中发挥的积极作用,列举了开放实验对培养学生创新意识和创新能力的重要意义,并提出了进一步做好遗传学教学实验室建设的一些设想。  相似文献   
    50.
    The evolution of sporulating bacteria in full-scale composting facilities with online temperature monitoring has been poorly studied, although organic matter recycling increases. We analysed Clostridium perfringens and sulphite-reducing clostridia (SRC) by cultivation, and streptomycetes by real-time PCR in five full-scale, temperature-monitored and aerated composting processes, and two pilot-scale drum composters. Facilities composted woodchips, sawdust, peat, or bark amended sludge or source-separated biowaste. Streptomycetes genes of 0.21-110 × 107 copies/g feed increased fast to 0.019-33 × 109 copies/g, and then were equal or decreased. SRC of 0.06-2.2 × 107 cfu/g feed decreased to 0-600 cfu/g, with re-growth in two facilities. End products were clean of C. perfringens, detected in sludge composts. Although processes contained large quantities of spore-forming bacteria, in the best facilities end products had the high quality. Temperature (>55 °C, >2d) was not related to the end compost quality, but relations between waste and bulking agent qualities, aeration, and processing time should be better controlled.  相似文献   
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