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81.
82.
The amounts of enzyme proteins of peroxisomal β-oxidation in fibroblasts and chorionic villous cells from infants with Zellweger syndrome and in fibroblasts, amniocytes, and chorionic villi from healthy controls were measured by immunoblot analysis. Immunoreactive proteins of peroxisomal acyl-CoA oxidase and 3-ketoacyl-CoA thiolase were absent in fibroblasts and chorionic villous cells from the patients, yet these enzyme proteins were present in fibroblasts, cultured amniocytes, and chorionic villi from the normal controls. These results show that immunoblot analysis of peroxisomal β-oxidation enzymes in amniocytes and chorionic villous cells is of potential value for the prenatal detection of Zellweger syndrome.  相似文献   
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84.
Dimethylamine was found to be nitrosated photochemically in aqueous solution containing nitrite both by the irradiation with a high pressure mercury lamp and by the exposure to sunlight to give nitrosodimethylamine, a well-known carcinogen. The nitrosation occurred more readily at alkaline pH than at acidic and neutral pH. These findings suggest that nitrosodimethylamine is produced photochemically under natural environmental conditions.  相似文献   
85.
Total column abundances of CO, HCN, C2H6, and C2H2 have been retrieved from infrared solar spectra observed at Moshiri (44.4°N) and Rikubetsu (43.5°N) in northern Japan from 1997 to 2005. The spectra were recorded with high spectral resolution ground-based Fourier transform infrared (FTIR) spectrometers and total column abundances were calculated by SFIT1 version 1.09e. Deviations of these species relative to their seasonal mean values (ΔCO, ΔHCN, ΔC2H6, and ΔC2H2) were derived, which showed short-time enhancements in 1998, 2002, and 2003. Good correlations among ΔCO, ΔHCN, ΔC2H6, and ΔC2H2 in a few months of each year were seen. Since the number of forest fires in Siberia had large enhancements in 1998, 2002, and 2003, trajectory analyses were performed in order to assess the influence of forest fires and it was confirmed that air masses passing over the location of burning points in Siberia reached Moshiri and Rikubetsu. This paper shows that enhancements of these species were driven by biomass burning in Siberia.  相似文献   
86.
Awareness is needed of sustainability issues that are currently neglected but potentially important. A computer-based approach can highlight unconscious and neglected areas because it can structure vast amounts of knowledge. In this article, we propose a methodology to perceive unconscious areas of sustainability with the support of a computer-based approach, which creates a matrix, named the recognized-unrecognized matrix, which highlights both local and globally neglected problems. A case study is conducted to consider the potential contribution of the aviation industry to sustainability issues. We demonstrate that a citation network analysis is an effective methodology to chart the recognized-unrecognized matrix. We highlight issues of water use in the aviation industry by designing an innovative water and air circulation system, which significantly reduces water and fuel consumption on board airplane flights. We also suggest a new approach to integrating both explicit and tacit knowledge to enable knowledge creation.  相似文献   
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Kitada Y  Kawahata H  Suzuki A  Oomori T 《Chemosphere》2008,71(11):2082-2090
To investigate the deteriorating health of coral reefs in Okinawa, Japan, natural sediment samples were analyzed for diuron, Irgarol 1051, chlorpyrifos, and bisphenol A (BPA) which are hazardous to corals. Samples were analyzed by solid-phase extraction (SPE) followed by high-performance liquid chromatography with tandem mass spectrometry (LC–MS–MS). Although diuron and chlorpyrifos usage is only well recorded for farms and not for cities, these chemicals were detected in both rural and urban areas. Additionally, diuron concentration in urban areas was in some cases higher than in rural areas, which might be caused by greater consumption of these chemicals in home gardens in city areas. Irgarol 1051 was detected in downstream river areas, which are situated far from the source sites such as pier or fishery harbor (0.6–3.2 km). This result suggested that Irgarol 1051 could be transported from the river mouths to the sampling sites during flood tides. High BPA concentrations were associated with urban areas (<1.2–22.0 μg kg−1), while low concentrations were associated with rural areas (nd–6.8 μg kg−1). The river sediments under study are delivered to coral reefs in large quantity through runoff caused by typhoons and other heavy rains. The highly hazardous chemicals are carried into coral reefs on these sediments. Therefore, these hazardous chemical substances may already be influencing the coral reefs.  相似文献   
89.
Occurrence of flame retardants (FRs) in the indoor environment of highly flame-retarded public facilities is an important concern from the viewpoint of exposure because it is likely that FRs are used to a greater degree in these facilities than in homes. For this study, brominated flame-retardants (BFRs) and organophosphate flame-retardants and plasticizers (OPs), and brominated dibenzo-p-dioxins/furans (PBDD/DFs) were measured in eight floor dust samples taken from a Japanese commercial hotel that was assumed to have many flame-retardant materials. Concentrations of polybrominated diphenylethers (PBDEs) and hexabromocyclododecanes (HBCDs) varied by about two orders of magnitude, from 9.8–1700 ng/g (median of 1200 ng/g) and from 72–1300 ng/g (median of 740 ng/g), respectively. Concentrations of the two types of BFRs described above were most dominant among the investigated BFRs in the dust samples. It is inferred that BFR and PBDD/DF concentrations are on the same level as those in house and office dust samples reported based on past studies. Regarding concentrations of 11 OPs, 7 OPs were detected on the order of micrograms per gram, which are equivalent to or exceed the BFR concentrations such as PBDEs and HBCDs. Concentrations of the investigated compounds were not uniform among dust samples collected throughout the hotel: concentrations differed among floors, suggesting that localization of source products is associated with FR concentrations in dust. Passive air sampling was also conducted to monitor BFRs in the indoor air of hotel rooms: the performance of an air cleaner placed in the room was evaluated in terms of reducing airborne BFR concentrations. Monitoring results suggest that operation of an appropriate air cleaner can reduce both gaseous and particulate BFRs in indoor air.  相似文献   
90.
As a method to prevent or mitigate cone discharges in a specific section such as a large silo, we have developed a new feedback control-type ionizer system. The feedback control-type system is composed mainly of an ionizer, an electrostatic field strength meter, and computer control equipment. In this study, we evaluated experimentally the practical version of the feedback control-type ionizer system through several tests in a pneumatic powder transport facility. The specific charges of the falling pellets in the silo were also measured for 10 s using a Faraday cage. Polypropylene (PP) pellets with a mean particle size of 3 mm were used in this experiment. The results of the experiment revealed that the feedback control-type ionizer system had the following characteristics: (1) it is possible to control the performance of the ionizer with a supply current; (2) the electrostatic field strength in the loading pipe from the charged powder is reduced and maintained at near zero by using the feedback control-type system; and (3) the performance of the feedback control-type system is superior to that of others, such as the conventional AC- or DC-type ionizers.  相似文献   
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