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111.
The present research was intended to determine the suitability of the CALUX assay as a screening method for dioxins in fish oil used as a feed ingredient in Japan. Alteration of TEQ in fish oil according to newly proposed toxic equivalency factors (TEF) is also discussed. In the analysis, polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (DL-PCBs) in 41 fish oil samples were determined by using high-resolution gas chromatography/high-resolution mass spectrometry (HRGC/HRMS) and CALUX bioassay. The mean TEQ values derived from 1998 WHO-TEF of PCDD/Fs and DL-PCBs were 2.6 and 9.9 pg g(-1) (ww), respectively. The levels of TEQ derived from the recently re-evaluated 2005 WHO-TEF were slightly lower than those of the former in both groups. Notably, the contribution of mono-ortho DL-PCBs to total 2005 WHO-TEQ was considerably decreased compared to the case of 1998 WHO-TEQ, resulting from the reduction in its TEF values, while the non-ortho DL-PCBs contribution was increased. The mean TEQ determined by CALUX assay for PCDD/Fs was approximately three times higher, whereas DL-PCBs was approximately two times lower than WHO-TEQ determined by HRGC/HRMS; the sum of PCDD/Fs and DL-PCBs was very similar by both methods. The correlation coefficients of TEQ between the CALUX assay and HRGC/HRMS analysis were 0.84, 0.89, and 0.90 for PCDD/Fs, DL-PCBs, and the sum, respectively. These results suggest that the CALUX assay is a very useful method for the screening of dioxin-related compounds in fish oils.  相似文献   
112.
The air temperature distributions in August (summer) and December (winter) were measured in an approximately 15 × 15-km urban area in Hyogo Prefecture, Japan, in order to study the spatial distribution of the air temperature and to propose effective measures against the heat island phenomenon. The air temperature was measured mainly by using thermometer shelters installed in an elementary school and a junior high school. The characteristic air temperature distribution depended on the season. The air temperature was higher inland than in the coastal region in August but was higher in the coastal region in December. The air temperature index indicated that the area where higher air temperatures would most likely appear was 5 to 10 km inland from the coast in August and around the coast in December. The seasonal air temperature distribution was presumably due to the strength of solar radiation and anthropogenic exhaust heat.  相似文献   
113.
Syntheses of some metabolites of ubiquinone and of related compounds are described. Idebenone (QSA-10), a methyl-dimethoxy-benzoquinone bearing an omega-hydroxydecyl side chain in 3-position, restored the oxidation of succinate and of NADH in ubiquinone-depleted mitochondrial preparations and showed a stabilizing effect on lysosomal membranes and an inhibitory effect on cAMP-phosphodiesterase. It inhibited lipid peroxidation in canine brain mitochondria and in microsomes from canine brain and rat liver. Administered orally to rats, it increased the respiratory control index for glutamate and succinate oxidation but had no effect on the ADP/O2 ratio. Pharmacological effects of idebenon are also briefly discussed.  相似文献   
114.
115.
Authors review the importance of studying the effects of electromagnetic fields (EMF) on microcirculatory system, especially in respect of possibility that vasculature may have direct and indirect role in interaction of static magnetic fields (SMF). We outline the physiological importance of microcirculation and relatively new methods of evaluation technique in vivo and explain in details the local and/or whole body exposure effects of SMF with␣range of 0.3–180 mT, power frequency EMF with range of 0.1–30 mT and microwaves at 1.5 GHz with range 0.08–8 W/kg brain average specific absorption rate (SAR) on microcirculatory systems in different tissues in experimental animals.  相似文献   
116.
Enforcement of the Automobile Recycling Law in Japan requires utilization of automobile shredder residue (ASR). However, the high contents of copper (∼5%) and chlorine (∼1%) in ASR stand in the way of practical application. We studied methods for the removal of copper and chlorine from ASR so that it could be utilized as a fuel. By compression of the ASR for solidification with an extruder, the polyvinylchloride (PVC) that covered electrical cables was softened and stripped from the copper wire. The solidified ASR was comminuted with cutter mills and classified by dry density separation. The copper content of the obtained light products was 0.2%–0.5%. Furthermore, we studied the possibility of dechlorination of the ASR by mechanochemical (MC) activation. The light product of the ASR was milled with CaO or CaCO3. The chlorine content decreased to about one-tenth of the original value after MC activation over 8 h. Therefore, the combined processing of softening–stripping and comminution liberated the PVC-covered cables and decreased the copper content of the ASR. In addition, dechlorination of the ASR was also possible by MC activation with the addition of calcium compounds.  相似文献   
117.
The present study was conducted to analyze the ratification status of International Labour Organization (ILO) conventions related to occupational safety and health (OSH) by ILO member states in terms of national indicators (length of ILO membership and national income status) and regional affiliation. 17 conventions designated as OSH-related by the 2003 International Labour Conference were examined. In general, countries with longer ILO membership ratified higher numbers of conventions related to OSH. With some variation, long-membership countries had the largest number of ratifications, followed by middle- and short-membership countries in all regions. There were also incremental increases in the number of ratifications for OSH-related conventions according to the national income status. Common regional characteristics that could not be explained by the factors studied also existed. Future efforts to increase ratification at an international level will need to consider the factors influencing ratification practice among the member states.  相似文献   
118.
Gielen D  Yagita H 《Ambio》2002,31(1):14-20
The NEAT model (Nonenergy-use Emission Accounting Tables) has been developed in order to estimate CO2 emissions caused by so-called nonenergy use of fossil fuels. The model is based on material flow accounting. The model has been applied to a number of countries in order to validate and improve its use. This paper discusses the case study for Japan. The NEAT analysis suggests that emissions in 1996 were 23 Mt higher than previously estimated based on the guidelines of the Intergovernmental Panel on Climate Change (IPCC). This quantity equals 1.9% of the total Japanese greenhouse gas emission. It is recommended to adjust the Japanese emission accounting practice and to apply more detailed emission estimation methods in future years. Given similar results for other countries it is also recommended to improve the IPCC guidelines.  相似文献   
119.
Investing in safety an analytical precautionary principle   总被引:6,自引:0,他引:6  
PROBLEM: Governments and businesses must respond to increasing safety requirements and balance the associated costs with productivity and competing pressures. METHOD: A real options approach has been introduced for decision making in the private sector; this approach is adapted for regulatory decisions that can involve irreversible and uncertain safety impacts, social costs that differ from private costs, and differences in perception among the stakeholders. RESULT AND IMPACT ON INDUSTRY AND GOVERNMENT: The outcome is an economic decision gage that determines if it is optimal to invest in safety even if the estimated costs significantly exceed the estimated benefits. Applications potentially include safety decisions related to aviation, ground transportation, pipelines, nuclear facilities, natural disaster planning, and terrorism, among others.  相似文献   
120.
壬基酚聚氧乙烯醚在MBR 与CASR 中的行为   总被引:1,自引:0,他引:1       下载免费PDF全文
对比研究了壬基酚聚氧乙烯醚(NPnEO, n 为1~4)在膜-生物反应器(MBR)和传统活性污泥反应器(CASR)中的去除效果和迁移行为.结果表明,在相同NPnEO 污泥负荷的条件下,采用不主动排泥的运行模式,2 种反应器均能有效去除NPnEO,去除率分别为99.2%和97.1%,MBR 的去除效果更稳定.前21d 中,2 种反应器中混合液NPnEO 浓度均呈现先增大后减小的趋势,但MBR 出水NPnEO 浓度小于其混合液浓度,而CASR 出水浓度则高于其混合液浓度;21d 后,2 种反应器混合液与出水浓度均趋于一致.活性污泥对NPnEO 具有吸附作用,但对去除NPnEO 的贡献很小;推测生物降解是去除NPnEO 的主导作用.  相似文献   
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