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991.
992.
Use and disposal of large home electronic appliances in Vietnam 总被引:1,自引:1,他引:0
Duc-Quang Nguyen Eiji Yamasue Hideyuki Okumura Keiichi N. Ishihara 《Journal of Material Cycles and Waste Management》2009,11(4):358-366
In this study, e-waste flows of five large home appliances (color televisions, refrigerators, washing machines, personal computers,
and air conditioners) in Vietnam are investigated. A social survey was performed to investigate the situation on using appliances
in households as well as on the disposal of appliances by the first users. Future quantities of e-waste were estimated using
a model that combines use of the Weibull distribution, the logistic function, and the population balance model. It was forecast
that about 3.86 million appliances, or 114 000 tons, will be discarded in 2010, and about 17.2 million appliances, or 567
000 tons, in 2025, showing a rapid increase of e-waste in the near future. 相似文献
993.
Large-scale patterns of shell variation in Littorina striata, a planktonic developing periwinkle from Macaronesia (Mollusca: Prosobranchia) 总被引:2,自引:1,他引:1
Littorina striata King and Broderip, 1832 is a strictly Macaronesian, intertidal periwinkle with planktonic development. The species displays
a high degree of shell variation involving size and sculpture (nodulose vs smooth shells). The present work provides a preliminary
account of some aspects of this shell variation on wave-exposed shores over the entire geographical range of the species.
Based on morphological patterns observed among other prosobranchs it was predicted that southern specimens of L. littorina should on the average be larger, heavier, more nodulose, and should show more shell repair marks, than northern specimens.
These expectations were confirmed for shell size and weight. In contrast, there was no consistent pattern in nodulosity between
archipelagos, even though there were differences at much smaller scales. Shell repair marks were more prevalent in northern
populations, but this trend was only due to a significant N–S difference among nodulose shells. This is surprising as nodulose
shells displayed significantly fewer shell repair marks than smooth shells. These observations were tentatively interpreted
as a function of presumed differential N–S patterns of wave action and ambient temperatures. In this context, wave action
in Macaronesia seems to increase in the south (contrary to what current theories predict). This atypical situation may confound
the interpretation of morphological patterns in L. striata so that firm conclusions cannot be drawn without further experimental work at different spatial scales. Nevertheless, it
seems that generalisations about macrogeographic shell morphology patterns, based on interspecific comparisons, are not directly
applicable to intraspecific patterns, and may strongly depend on local conditions which make adequate sampling and data treatment
very difficult.
Received: 10 September 1997 / Accepted: 15 January 1998 相似文献
994.
A. C. Engels L. Joyeux C. Brantner B. De Keersmaecker L. De Catte D. Baud J. Deprest T. Van Mieghem 《黑龙江环境通报》2016,36(3):266-273
The fetal central nervous system can already be examined in the first trimester of pregnancy. Acrania, alobar holoprosencephaly, cephaloceles, and spina bifida can confidently be diagnosed at that stage and should actively be looked for in every fetus undergoing first-trimester ultrasound. For some other conditions, such as vermian anomalies and agenesis of the corpus callosum, markers have been identified, but the diagnosis can only be confirmed in the second trimester of gestation. For these conditions, data on sensitivity and more importantly specificity and false positives are lacking, and one should therefore be aware not to falsely reassure or scare expecting parents based on first-trimester findings. This review summarizes the current knowledge of first-trimester neurosonography in the normal and abnormal fetus and gives an overview of which diseases can be diagnosed. © 2016 John Wiley & Sons, Ltd. 相似文献
995.
996.
M. Yu. Semenov T. V. Khodzher V. A. Obolkin V. M. Domysheva L. P. Golobokova N. A. Kobeleva O. G. Netsvetaeva V. L. Potemkin R. Van Grieken N. Fukuzaki 《Chemistry and Ecology》2006,22(1):1-11
Data from 3-year-long observations on the chemical composition of precipitation, atmospheric gases, aerosols, soils, and surface waters at three monitoring stations in the Baikal region are presented. The stability of terrestrial ecosystems and surface waters to acidification has been estimated quantitatively. It has been shown that, unlike soils, surface waters of the Baikal watershed are more sensitive to acid deposition. The permissible acidity load for soils and surface waters of the territory varied from 0.30 to 20.00 keq ha-1 yr-1, whereas the maximal contemporary acidity load attains 0.50 keq ha-1 yr-1. 相似文献
997.
Diane Van Opstal Karin E.M. Diderich Marieke Joosten Lutgarde C.P. Govaerts Joke Polak Marjan Boter Jasper J. Saris Wai Yee Cheung Stefanie van Veen Robert van de Helm Attie T.J.I. Go Maarten F.C.M. Knapen Dimitri N.M. Papatsonis Anneke Dijkman Femke de Vries Robert-Jan H. Galjaard Lies H. Hoefsloot Malgorzata I. Srebniak 《黑龙江环境通报》2018,38(12):911-919
998.
999.
1000.
A monoclonal antibody (AAP-1), specific for the intestinal isoenzyme of alkaline phosphatase (ALP), has been used to develop an immunoassay for amniotic fluid samples. Values in the immunoassay correlated closely with those obtained by direct determination of phenylalanine-inhibitable ALP. A panel of 124 control second-trimester amniotic fluids and 21 fluids with a 1 in 4 risk of a cystic fibrosis fetus were examined in the immunoassay. Eight of 10 affected cases had values below an arbitrary cut-off of one third median, while all the non-affected cases were above this level. Almost identical results were obtained by enzymatic determination of phenylalanine-inhibitable ALP. However, in both systems the false positive rate (control fluids with values below one third median), was unacceptably high. It is pointed out that at present the most effective system for the prenatal diagnosis of cystic fibrosis is achieved by measuring the ratio of intestinal to total ALP in amniotic fluid supernatants. This is probably best effected by enzymatic assay in the presence of phenylalanine and homoarginine inhibition. 相似文献