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11.
The driving attitudes and self-reported behaviors of New Zealand adolescents in Year 10 of school (n = 168, mean age = 14.2 years) were compared with students in Year 12 (n = 109, mean age = 16.4 years). School year group differences were found for three out of the eight measures of risky attitudes and behaviors, with the older students having riskier responses in each case. Gender differences were found for four of these measures, with males consistently demonstrating riskier attitudes. Suggestions are made about appropriate interventions and the timing of these. 相似文献
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Mikael Hult María Jos Martínez Canet Peter N. Johnston Kazuhisa Komura 《Journal of environmental radioactivity》2002,60(3)
During the JCO-accident in Tokai-mura in 1999, the surrounding village was irradiated by an uncontrolled neutron flux. At some locations in that village, the thermal neutron flux was determined retrospectively by measurement of the very low activity of 51Cr and 60Co in stainless-steel spoons using γ-ray spectrometry in underground laboratories. Activities determined in the HADES underground facility are presented here, together with calibrations performed using a well-defined thermal neutron flux to directly estimate the fluence of thermal neutrons independent of most assumptions. The results show measurable 51Cr in three samples and 60Co in four samples taken from locations at distances of up to 430 m from the accident location despite the elapse of 4 half-lives of 51Cr before measurement. Effects of air transport of the samples were considered and shown to be negligible. 相似文献
13.
Aqueous solutions containing organic amines and metal complexes were applied for the removal of nitrogen oxides. Organic amines were effective for the removal of the mixture composed of nitric oxide and nitrogen dioxide. In particular, methyl and ethyl amines removed these species with 1 : 1 ratio from the mixture at fairly rapid rates. Dinitrogen trioxide (N2O3) was suggested to be involved in the course of the removal.Metal complexes removed nitrogen dioxide efficiently. As has been previously reported for a number of inorganic or organic redox systems, it was concluded that the removal of nitrogen dioxide by metal complexes proceeded also by the redox mechanism.Iron (ii) chelate complexes were highly effective for the removal of nitric oxide and this was attributed to a reversible coordination to the complex. 相似文献
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Takahashi K Otsuki T Mase A Kawado T Kotani M Ami K Matsushima H Nishimura Y Miura Y Murakami S Maeda M Hayashi H Kumagai N Shirahama T Yoshimatsu M Morimoto K 《Environment international》2008,34(6):765-772
BACKGROUND: Against increasing environmental adverse effects on human health such as those associated with water and ground pollution, as well as out- and indoor air conditions, trials were conducted to support and promote human health by improving the indoor air atmosphere. This study was performed to estimate the effect of negatively-charged air conditions on human biological markers related to the psycho-neuro-endocrino-immune (PNEI) network. OBJECTIVES: After construction of negatively-charged experimental rooms (NCRs), healthy volunteers were admitted to these rooms and control rooms (CTRs) and various biological responses were analyzed. METHODS: NCRs were constructed using a fine charcoal coating and applying an electric voltage (72 V) between the backside of walls and the ground. Various biological markers were monitored that related to general conditions, autonomic nervous systems, stress markers, immunological parameters and blood flow. RESULTS: Regarding the indoor environment, only negatively-charged air resulted in the difference between the CTR and NCR groups. The well-controlled experimental model-room to examine the biological effects of negatively-charged air was therefore established. Among the various parameters, IL-2, IL-4, the mean RR interval of the heart rate, and blood viscosity differed significantly between the CTR and NCR groups. In addition, the following formula was used to detect NCR-biological responses: Biological Response Value (BRV)=0.498+0.0005 [salivary cortisol]+0.072 [IL-2]+0.003 [HRM-SD]-0.013 [blood viscosity]-0.009 [blood sugar]+0.017 [pulse rate]. CONCLUSIONS: Negatively-charged air conditions activated the immune system slightly, smoothened blood flow and stabilized the autonomic nervous system. Although this is the first report to analyze negatively-charged air conditions on human biological responses, the long-term effects should be analyzed for the general use of these artificial atmospheres. 相似文献
15.
Ezoe Y Lin CH Noto M Watanabe Y Yoshimura K 《Journal of environmental monitoring : JEM》2002,4(4):533-540
In Yangmingshan National Park, located in the northern part of the Taiwan Island, there is a very rare area where fish (Channa asiatica) live in spite of acid environments. The origin of the acid in local acid ponds and rivers and the evolution of the water chemistry are discussed on the basis of sulfur stable isotope ratios and chemical equilibria. One of the sources of the acid is sulfuric acid, which is derived from the oxidation of hydrogen sulfide in volcanic gas gushing out from fumaroles around the area and from acid deposition supplied from Taipei City. It is also derived from the oxidation of pyrite: the sulfur stable isotope ratios of delta 34S of +1@1000 to +4@1000 (relative to CDT) of sulfate in acid pond waters (pH 3-4) could be related to those of hydrogen sulfide in volcanic gas, pyrite in local pond sediments and soils, and sulfate in rain water. One acid source is sulfuric and hydrochloric acids arising in springs from geothermal activity: the delta 34S values were characterised by +13@1000 to +17@1000 sulfate-S, which was provided by a disproportionation reaction of sulfur dioxide in the depths. Another acid source could be the oxidation of iron(II). Under acidic conditions, the water-rock reaction gives rise to high concentrations of aluminium and iron. While flowing down surface streams, iron(II) is oxidised to iron(III) and then hydrolysed to cause further acidification under oxic conditions. The concentrations of iron and aluminium are controlled by redox and dissolution equilibria. 相似文献
16.
If there are no clearly defined management procedures, medical waste may represent a source of serious health hazards. Medical waste management was evaluated at the three hospitals in the Nisava and Toplica district, in Serbia. All the stages of existing waste management (segregation, collection, storage, transportation and disposal of waste) were examined by interviewing the personnel involved in the management of waste. The generated waste was a mixture of hazardous and non-hazardous waste. The study found that waste management performance in this district was poor and that there were problems in every stage of management. The results indicate that the waste generation rate was 1.92 kg bed(-1) day(-1) and consisted of 98.7% general waste and 1.3% sharps. Inappropriate segregation practices were the biggest problem and led to increased quantities of general waste. There were no specific regulations for the segregation of the medical waste. None of the surveyed hospitals have a system to refine wastewater and there were no training courses about hospital waste management. 相似文献
17.
Richard G. Ryall David Callen Robert Cocciolone Amra Duvnjak Renata Esca Niki Frantzis Elizabeth M. Gjerde Eric A. Haan Trudy Hocking Grant Sutherland David W. Thomas Fiona Webb 《黑龙江环境通报》2001,21(7):553-557
Of the 65 328 pregnancies of South Australian mothers screened by the South Australian Maternal Serum Antenatal Screening (SAMSAS) Programme between 1 January 1991 and 31 December 1997, 3431 (5.25%) were declared at increased risk of fetal Down syndrome. Fetal or neonatal karyotype was determined in 2737/3431 (79.8%) of these pregnancies, including 16 with early fetal loss. Interrogation of the database of the South Australian Neonatal Screening Service showed 643 live-born infants whose phenotype was not subsequently questioned among the 694 pregnancies whose karyotype was not determined. Of the remaining 51/3431 pregnancies, 19 ended in early fetal loss without karyotyping and no newborn screening or other records could be found for 32 cases. The 129 instances of abnormal karyotype found were Down syndrome (84), trisomy 18 (four), trisomy 13 (three), triploidy (two), female sex chromosome aneuploidy (six) and male sex chromosome aneuploidy (five), inherited balanced rearrangements (19), mosaic or de novo balanced abnormalities (four) and unbalanced karyotypes (two). In the pregnancies declared at increased risk of fetal Down syndrome, only the karyotype for Down syndrome occurred with a frequency greater than that expected for the general, pregnant population. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
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19.
Takeshi Osawa Kazuhisa Yamasaki Ken Tabuchi Akira Yoshioka Mayura B. Takada 《Ambio》2018,47(7):806-815
Detecting dispersal pathways is important both for understanding species range expansion and for managing nuisance species. However, direct detection is difficult. Here, we propose detecting these crucial pathways using a virtual ecology approach, simulating species dynamics using models, and virtual observations. As a case study, we developed a dispersal model based on cellular automata for the pest insect Stenotus rubrovittatus and simulated its expansion. We tested models for species expansion based on four landscape parameters as candidate pathways; these are river density, road density, area of paddy fields, and area of abandoned farmland, and validated their accuracy. We found that both road density and abandoned area models had prediction accuracy. The simulation requires simple data only to have predictive power, allowing for fast modeling and swift establishment of management plans. 相似文献
20.
Land Degradation at the Stara Planina Ski Resort 总被引:1,自引:0,他引:1
The environmental impacts of ski resorts in the Balkan region are great and can lead to landscape degradation and loss of
land functionality. In this study, we present an example of the negative effects of human activities at the Stara Planina
ski resort in southeastern Serbia. The objective of this study is detailed analysis of the characteristics of environmental
impacts at the Stara Planina. The management of the ski area and ski slope development caused severe degradation of topsoil
and native vegetation. The morphological characteristics of the area, lithological properties of the exposed material and
climate conditions resulted in various geomorphic impacts, including rills, deep gullies, solifluctions and debris from rock
weathering. Significant changes in land usage altered hydrological conditions, resulting in more frequent torrential floods
in the downstream sections of the Zubska River and increased the sediment yield. Environmental impacts were analyzed in the
immediate and wider zones of the ski resort in accordance with the specific topography and visual exposure. The restoration
and erosion control measures have stopped degradation processes and helped to rehabilitate the appearance and functions of
the landscape. The results show the importance of considering lithological (the type and characteristics of minerals present)
and hydrological (precipitation, water storage capacity of soil, runoff) factors under the conditions of significant changes
in land usage. The results of this investigation can contribute to the improvement of planning processes and the implementation
of development projects in ski areas. 相似文献