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171.
Brian Gulson Karen Mizon Michael Korsch Honway Louie Michael Wu Jenny Stauber J. Michael Davis Alan Taylor 《中国地球化学学报》2006,25(B08):62-62
This is a 4-year longitudinal study to evaluate changes to the environment and exposure of young children associated with the introduction of methylcyclopentadienyl manganese tricarbonyl (MMT) into Australia in 2000. The cohort includes 57 females and 56 males; age range of 0.29 to 3.9 years. Samples are collected every 6 months from children in residences located at varying distances from major traffic thoroughfares in Sydney. Environmental samples: air, house and day care dustfall, soil, dust sweepings and gasoline. Samples from children: blood, urine, handwipes prior to and after playing outdoors, and a 6-day duplicate diet. All samples are analyzed for a suite of 20 elements using ICP-MS. Results are presented for the first three 6-month sampling periods for Pb and Mn. For dustfall accumulation, there was no significant change over the 3 sampling periods (time) for Pb or Mn, and a positive relationship between ‘traffic exposure' (traffic volume and proximity to the road) and Pb but not Mn. For handwipes, Pb and Mn in wipes taken from children after playing outdoors were usually significantly greater than for wipes taken prior to playing. There was no significant association between Pb or Mn in handwipes with traffic exposure. Dustfall accumulation was a significant predictor for Pb in the handwipes, and dust sweepings were a significant predictor of Mn in handwipes. 相似文献
172.
Norboo Tsering 《中国地球化学学报》2006,25(B08):69-69
Background: Radiographic signs of Pneumoconiosis found in farming Ladakhi despite absences of mines and industries were believed to be due to exposure to frequent dust storms and domestic fire pollutions. Seasonal Koilonychia (spoon nail) occurring predominantly in farming women in absences of iron deficiency anaemia was thought to arise from exposure to water made alkaline by weathering of hornblende minerals. The relation of these health conditions to environmental geohydrochemistry is postulated as the source of irrigation water in the affected population originates from glaciers in trans-Himalaya range of sedimentary geology and steep landscape favouring flushing of silica/silicate containing silts. Methods and results: Survey in two central Ladakh villages revealed radiographic evidence of silicosis in all middle aged women and half in middle aged men. In a large-scale study of 3105 subjects aged over 30 years from three villages; 101 (22.5%) of the 449 radiographed showed signs of pneumoconiosis (ILO 1980 criteria) including eggshell calcification of hilar gland and progressive massive fibrosis. Indoor dust analyzed using Philips 400T electron microscope with energy dispersive analysis system attached showed SiO2 levels upto 53.27% with particle size of 0.5 to 5.0 microns and the concentration during cooking period in the worst affected area was 7.495 mg/m^3. Microscopy and histopathology from the subject was characteristic of pneumoconiosis. Analysis of the inorganic dust in the lung showed 40.2% muscovite, 37.3% quartz with the extracted dust wt 147.9 mg/gm of dry tissue. Prevalence of chronic cough with chronic phlegm and percentage of villagers with FEV1/FVC ratio of less than 65% rose with age. Of 70 subjects studied 19 women and 2 men had Koilonychia with incidence being highest in summer. Absence of seasonal Koilonychia in villages fed by water derived from northern mountain range glaciers with mainly igneous geology supports our hypothesis. 相似文献
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《云南地理环境研究》2006,18(6):97-97
据日前“中国科学文献计量评价研究中心”提供的最新《中国学术期刊综合引证年度报告(2006)》(统计源刊6182种),本刊影响因子再创新高,达0.961,五年影响因子0.815,在云南省的全部期刊中名列第一,并遥遥领先!(全国排名尚未查到)。 相似文献
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众所周知,地理学是研究人类生存和发展的地理环境,以及人类与地理环境关系的一门科学。它既具有科的属性,同时也具有理科的属性。但是长期以来,中学地理一直被视为科,使中学地理不能以其本来完整的面貌展现在学生面前。因此,在中学地理课程中开设地理实践活动课,意义重大、影响深远,因为这不仅涉及到学生学习方法的改革,也涉及到教师教育、教学方法的改革,更重要的是涉及到教学观念与地理观念的更新。 相似文献
179.
在当代认知发展及智力研究领域,美国耶鲁大学心理学教授斯腾伯格(R.J.Sternberg)无疑是一位活跃人物。其代表性的理论建树是智力结构三重模式,并于1996年发展为成功智力理论。这是与加德纳(H.Gardner)多元智力理论同具影响力的理论,更为重要的是成功智力理论得到了大量的实验和教学实证研究的证实。 相似文献
180.
人教版地理七年级“澳大利亚”一节,延续了前几章国家地理的编写体例:第一,打破了对自然和人地理的面画俱到,突出国家特有的自然环境及经济发展特点;第二,把人与环境的关系作为主线,为培养学生综合分析地理事物的能力创造条件;第三,教材安排了相当数量的活动,通过探究完成教材的三个组成部分:世界活化石博物馆、骑在羊背上的国家和坐在矿车上的国家。根据地理新课标、教材和学生的学习特点及发展要求,结合学生已有的知识水平,学习目标设计如下: 相似文献