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51.
In this paper we show that under double constraint the goods derived from secondary materials could be Giffen. The example is given of paper derived from waste recycling. We show that if the policy maker misunderstands the type of goods, because he incorrectly considers a Giffen good to be normal, the results of his economic policy could be opposite to his goals. Finally, we make some considerations to generalize our results, and suggest topics for further research. 相似文献
52.
Librando V Tringali G Hjorth J Coluccia S 《Environmental pollution (Barking, Essex : 1987)》2004,127(3):403-410
Dimethylsulphide (DMS) gas phase oxidation with OH radicals was investigated by long path FT-IR spectroscopy and by ion chromatography (IC) and HPLC-MS2 to quantify the reaction products and evaluate heterogeneous processes. The experiments were performed considering two different NOx (NO2+NO) levels. The initial concentration of NO2 was varied from 24 ppbV (NOx=1 ppmV) to 953 ppbV (NOx=10 ppmV). Photolysis of H2O2 was used as the OH-radical source. SO2, dimethylsulphoxide (DMSO), dimethylsulphone (DMSO2), methanesulphonic acid (MSA), methanesulphinic acid (MSIA) and methane sulphonyl peroxynitrate (MSPN) were identified as the main sulphur-containing products. The results indicate that higher NOx levels play a significant role in the chemistry of CH3S(O)x radical, influencing both the SO2/MSPN ratio and the amount of the sulphur species in the condensed phase, and that the NO2/NO ratio could influence the trends in the molar yields of the different products. For this reason the NOx content results a limiting parameter when on measure DMS in atmospheric environment. 相似文献
53.
Bruno Brambati Giuseppe Simoni Maurizio Travi Cesare Danesino Lucla Tului Orsola Privitera Sabine Stioui Silvana Tedeschi Silvia Russo Paola Primignani 《黑龙江环境通报》1992,12(10):789-799
Transabdominal chorionic villus sampling (TA-CVS) was attempted in 328 high-risk pregnancies at 6–7 weeks of gestation. Sampling was feasible in 97.7 per cent of cases; chorionic tissue specimens of more than 10 mg were obtained in 94.4 per cent ofcases at the first needle insertion and in 100 per cent after a second attempt. Fetal karyotyping succeeded in 99.4 per cent of cases, while no diagnostic failures were reported in enzymatic and DNA analyses. Fetal loss rate in the first 4 weeks after CVS was significantly higher than in the later CVS series (7.2 vs. 2.5 per cent), but 50 per cent of losses were observed within 2 weeks in cases of inviable aneuploidies. A high incidence of severe limb abnormalities (1.6 per cent) was detected in pregnancies intended to continue, confirming the aetiological role of early CVS. Unclear visualization of the placental limits and poor control of the needle path are thought to be the main reasons for the vascular disruption of the chorionic plate, and thereby hypoxic embryo tissue damage. A better selection of cases, together with high-resolution vaginal ultrasound visualization, and analytical techniques requiring a minimal amount of tissue should avoid any teratogenic effect of early CVS. 相似文献
54.
Paolo Gasparini Giuseppe Novelli Anna Savoia Bruno Dallapiccola Pier Franco Pignatti 《黑龙江环境通报》1989,9(5):349-355
Eight pregnancies at risk for cystic fibrosis have been monitored by first-trimester prenatal diagnosis with DNA amplification analysis. The polymerase chain reaction (PCR) was used in all cases to amplify the region detected by KM 19. In two cases, the region detected by CS·7, another DNA probe tightly linked to the CF locus, was also examined. The results of the PCR determinations were confirmed using the Southern blotting procedure, by segregation analysis of restriction fragment length polymorphisms (RFLPs) relative to XV-2c, J3·11, metH, metD, and KM19 probes. 相似文献
55.
Giuseppe Cocconi 《Die Naturwissenschaften》1941,29(22-23):336-336
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57.
Mudskippers (Gobiidae: Oxudercinae) are amphibious gobies. The occurrence and habitats of seven sympatric species of Malayan
mudskippers were recorded: Boleophthalmus
boddarti, Boleophthalmus
pectinirostris, Periophthalmodon schlosseri, Periophthalmus chrysospilos, Periophthalmus gracilis, Periophthalmus variabilis and Scartelaos histophorus. A total of 14 surveys were made at six localities along 120 km of the west coast
of the Malay Peninsula in August 1996 and September 2006. A multivariate set of ordinal parameters were used to measure the
quantity of environmental water in mudskippers’ habitats, and three guilds of species were discriminated. The resulting pattern
mirrored the adaptive scenario depicted by physiological and anatomical studies of mudskippers’ terrestriality, although in
one case a terminal taxon was less terrestrial than other more basal ones. Differentiation of trophic niches may also play
a role in habitat selection by the herbivorous Boleophthalmus spp., which were only found in unvegetated, illuminated areas and on wet mud at low tide. With the more terrestrial guild,
a significant negative co-occurrence suggested direct interspecific competition.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
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60.
Mentore Vaccari Veronica Di Bella Francesco Vitali Carlo Collivignarelli 《Waste management (New York, N.Y.)》2013,33(2):277-286
In Bosnia and Herzegovina only 50% of the municipalities have a well-organized service for (mixed) waste collection and disposal. Illegal dumping is very common, in particular in rural areas, which are not regularly served by any service of collection. This situation leads to serious risks for public health and has dangerous environmental impacts. In Zavidovi?i the municipality is trying to meet high standards in the delivery of services of waste collection, but is constrained by scarce financial and technical resources. Different scenarios for the implementation of a system of separate collection in Zavidovi?i were elaborated in order to provide a useful tool for decision making by comparing costs and environmental & economic benefits of each scenario. Six scenarios were considered, based on different recovery rates for plastic, paper & cardboard, and metals. Benefits resulting from the implementation of each of the proposed scenarios are compared in terms of savings of landfill volume and costs. The study concludes that the adoption of a system of separate collection could generate positive impacts on all the stakeholders involved in the solid waste management sector in Zavidovi?i and could contribute to the compliance of European standards in many Central and Eastern European countries as established by a number of national environmental protection strategies. 相似文献