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81.
We investigate the stock market response to firm disclosure of positive environmental information and the link from that information to environmental outcomes. We classify environmental media releases by informational content and value relevance, and assess the abnormal stock returns of each type of event. While announcements of future environmental activities lead to the largest favorable stock market reactions, there is no guaranteed link from this type of information to environmental outcomes. Further analysis of the abnormal returns shows that the magnitude of the stock market reaction depends on firm financial characteristics across all event types rather than on firm environmental performance. Our results indicate that the ability for voluntary environmental information disclosure to induce environmental self-regulation is limited to the extent that firms are able to follow through with their announcements of planned environmental activities. 相似文献
82.
We examine the pass-through of wholesale prices to retail prices in the market for E85, which contains 51%–83% ethanol, and in the much larger market for E10, which contains 10% ethanol. We use a panel dataset consisting of monthly observations from 2007 to March 2015 on wholesale and retail prices for 274 Minnesota gas stations that sell both E10 and E85. Consistent with prior research, the cumulative pass-through coefficient for E10 is 1.00 after one month. In contrast, the E85 market is sparse, and although pass-through increased over time, we estimate it to be only 0.53 statewide from 2012 to 2015. Pass-through is higher at stations with more local E85 competitors. In the Twin Cities, which has a high density of E85 stations, pass-through is nearly complete, but outside the Twin Cities slightly less than half the wholesale discount of E85, relative to E10, is passed on to the consumer. 相似文献
83.
We analyze the effect of CEO education on environmental decision-making. Using a unique sample of Danish firms from 1996 to 2012, we find that CEO education significantly improves firms' energy efficiency. We seek to derive causality using health shocks: the hospitalization of highly educated CEOs induces a drop in energy efficiency, whereas the hospitalization of less educated CEOs does not have any significant effect. Exploring the mechanisms at play, we show that our results are largely driven by advanced education in business degrees. Moreover, we show that CEO education is associated with greater environmental awareness: highly educated CEOs exhibit greater concerns for climate change, as measured by a survey of social preferences, and drive more environmentally efficient cars. Taken together, our findings suggest that education shapes managerial styles giving rise to greater sustainability in corporate actions. 相似文献
84.
K. Srogi 《Environmental Chemistry Letters》2007,5(4):169-195
Polycyclic aromatic hydrocarbons (PAHs) are a large group of organic compounds with two or more fused aromatic rings. They
have a relatively low solubility in water, but are highly lipophilic. Most of the PAHs with low vapour pressure in the air
are adsorbed on particles. When dissolved in water or adsorbed on particulate matter, PAHs can undergo photodecomposition
when exposed to ultraviolet light from solar radiation. In the atmosphere, PAHs can react with pollutants such as ozone, nitrogen
oxides and sulfur dioxide, yielding diones, nitro- and dinitro-PAHs, and sulfonic acids, respectively. PAHs may also be degraded
by some microorganisms in the soil. PAHs are widespread environmental contaminants resulting from incomplete combustion of
organic materials. The occurrence is largely a result of anthropogenic emissions such as fossil fuel-burning, motor vehicle,
waste incinerator, oil refining, coke and asphalt production, and aluminum production, etc. PAHs have received increased attention
in recent years in air pollution studies because some of these compounds are highly carcinogenic or mutagenic. Eight PAHs
(Car-PAHs) typically considered as possible carcinogens are: benzo(a)anthracene, chrysene, benzo(b)fluoranthene, benzo(k)fluoranthene,
benzo(a)pyrene (B(a)P), dibenzo(a,h)anthracene, indeno(1,2,3-cd)pyrene and benzo(g,h,i)perylene. In particular, benzo(a)pyrene
has been identified as being highly carcinogenic. The US Environmental Protection Agency (EPA) has promulgated 16 unsubstituted
PAHs (EPA-PAH) as priority pollutants. Thus, exposure assessments of PAHs in the developing world are important. The scope
of this review will be to give an overview of PAH concentrations in various environmental samples and to discuss the advantages
and limitations of applying these parameters in the assessment of environmental risks in ecosystems and human health. As it
well known, there is an increasing trend to use the behavior of pollutants (i.e. bioaccumulation) as well as pollution-induced
biological and biochemical effects on human organisms to evaluate or predict the impact of chemicals on ecosystems. Emphasis
in this review will, therefore, be placed on the use of bioaccumulation and biomarker responses in air, soil, water and food,
as monitoring tools for the assessment of the risks and hazards of PAH concentrations for the ecosystem, as well as on its
limitations. 相似文献
85.
86.
Summary. Male satin moths, Leucoma (Stilpnotia) salicis L. (Lepidoptera, Lymantriidae) were attracted only to (3Z,6R,7S,9R,10S)-isomer out of the four (3Z)-cis-6,7-cis-9,10-diepoxy-3-henicosenes (leucomalure). This was demonstrated by field trapping test with a bivoltine population in a mixed poplar-willow forest along the flood area of the river Danube at Adony, Hungary. 相似文献
87.
88.
G. H. Schuring-Blom M. Keuzer M. E. Jakobs D. M. van den Brande H. M. Visser J. Wiegant J. M. N. Hoovers N. J. Leschot 《黑龙江环境通报》1993,13(8):671-679
In first-trimester chorionic villus sampling (CVS) for prenatal diagnosis, abnormal chromosomal findings, such as mosaicism, trisomies, or suspect abnormal karyotypes, are found more frequently than at amniocentesis. The fact that these chromosomal abnormalities do not always reflect the fetal karyotype but may be restricted to the placenta is a major problem in diagnosis and counselling. In this paper we present the results of fluorescence in situ hybridization (FISH) studies on interphase nuclei of three term placentae investigated because of false-positive findings at first-trimester CVS. The chorionic villi of the first case showed a mosaic chromosome pattern involving a trisomy 10 cell line and a normal cell line, those of the second case a total trisomy 8 cell line, while in the third case a complete monosomy X was found. Follow-up amniocentesis in each of these three cases revealed a normal karyotype. By using FISH, we were able to confirm the presence of the aberrant cell lines, which were all confined to one part of the placenta. FISH on interphase nuclei allows the investigation of large numbers of cells for the existence of numerical chromosome aberrations in a quick and reliable way. 相似文献
89.
R. Lorenzo R. Kaegi R. Gehrig B. Grobty 《Atmospheric environment (Oxford, England : 1994)》2006,40(40):7831-7841
The goal of this study was to identify and quantify particles emitted from railway traffic. For that purpose PM10 samples were collected near a busy railway line using a wind direction and speed controlled sampling equipment consisting of five devices. Measurements taken perpendicular to the railway lines at 10, 36 and 120 m distance enable an identification and separation of particles caused by the railway traffic from background particles. Morphology and chemistry of more than 11,000 particles were analysed by computer controlled scanning electron microscopy (CCSEM). Based on chemical composition five particle classes are defined and assigned to their sources. The mass of the individual particles is determined by multiplying their volumes, calculated based on their morphology with a density assigned specifically to each particle class. The density of the particle classes is derived from their chemical composition. To estimate the PM10 contributions of the railway lines, the mass of PM10 at 120 m (background, not influenced by the railway lines) is subtracted from the mass of PM10 at 10 m. The emissions of the railway lines are dominated by ‘iron’ particles, which contribute 2.9 μg m−3 or 67% to the railway related PM10. In addition, ‘aluminium’ and ‘calcium’ particles contribute also to the railway related PM10 (1.0 μg m−3 or 23% for the ‘aluminium’ and 0.4 μg m−3 or 10% for the ‘calcium’ particles). These particles are assigned to abrasion of the gravel bed and re-suspension of mineral dust.Long-term gravimetric results of the contribution of iron to the mass of railway related PM10 from a study performed earlier at the same site are in good agreement with the data presented in this study. 相似文献
90.