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101.
This report summarizes evidence presented during the Third Annual Ignition Interlock Symposium at Vero Beach, Florida, 29 October 2002. The ignition interlock prevents a car from starting when blood alcohol concentration (BAC) is elevated. We review some of our prior work as well as introduce previously unpublished results to demonstrate the manner in which the data recorded by the alcohol ignition interlock device can serve as an advance predictor of future driving under the influence (DUI) of alcohol risks. Data used in this current report represent approximately 2,200 ignition interlock users from Alberta, Canada, and about 8,000 interlock users from Quebec, Canada; the Alberta data set contained 5.5 million breath tests and the Quebec data 18.8 million breath tests. All tests are time and date stamped and this information was used to characterize patterns of BAC and vehicle use, and the relationship between BAC elevations and DUI offenses that accumulated after the interlock was removed from the vehicles. Findings from Cox regression show that BAC elevations >.02-.04% are more potent predictors of repeat DUI (p<.0001) than even prior DUI (p<.006), usually found to be the strongest indicator of driver risk. Prior DUI obviously has no use for scaling the risk of first-time offenders. Drivers who are both multiple offenders and who have more than a few elevated interlock BAC tests are much more likely to repeat DUI. The timing and pattern of elevated BAC tests provided during the time drivers were required to use an alcohol ignition interlock device are remarkably similar on both a daily basis and an hourly basis when the interlock programs from the two provinces are compared directly. Both provinces had higher rates of elevated tests on Saturday and Sunday, and the fewest elevated tests on Tuesdays. The absolute rate of elevated tests is similar despite the two provinces adhering to different interlock lockout points (.02% Quebec;.04% Alberta). Charts tracking the Monday-Friday timing of elevated BAC tests by hour are nearly identical for both provinces. The most elevated BAC tests occurred between 7 and 9 A.M. Monday to Friday, even though most vehicle start attempts occurred much later in the day. This higher rate of elevated morning BAC likely represents drinking from the prior evening with alcohol not yet cleared from circulation; those with elevated BAC in the early morning were more likely to have a repeat offense even after accounting for prior DUI and the higher overall rate of elevated BAC tests. This is viewed as evidence of a drinking problem that will lead to impaired driving after the controlling function of the interlock is removed. Policy changes are discussed that might take better advantage of interlock information to improve the public response to drunk driving.  相似文献   
102.
Natura 2000 is a network of natural sites whose aim is to preserve species and habitats of relevance in the European Union. The policy underlying Natura 2000 has faced widespread opposition from land users and received extensive support from environmentalists. This paper addresses the ethical framework for Natura 2000 and the probable moral assumptions of its main stakeholders. Arguments for and against Natura 2000 were analyzed and classified according to “strong” or “weak” versions of the three main theories of environmental ethics – anthropocentrism, biocentrism, and ecocentrism. Weak (intergenerational) anthropocentrism was found to underlie the Natura 2000 network itself and the positions of environmentalists, while strong (traditional) anthropocentrism pervaded the positions of economic developers. Land users seemed to fall somewhere between weak and strong anthropocentrism. The paper discusses the relation between ethics and different attitudes towards Natura 2000, highlighting some of the implications for the network’s ongoing implementation. It is shown that Natura 2000 achieves a strong reversal of the burden of proof from conservation to economic development and land use change under anthropocentrism. It is argued that the alleged theoretical divide between anthropocentrism and non-anthropocentrism in relation to the burden of proof does not seem to hold in practice. Finally, it is predicted that the weak versions of anthropocentrism, biocentrism, and ecocentrism, are likely to converge extensively in respect to nature conservation policy measures.“Charting the depths of law and policy disputes yield an understanding of ethical differences.” Paul B. Thompson (2002, p. 189).  相似文献   
103.
In ancient Lake Baikal (East Siberia), freshwater sponges have diversified to an extraordinary degree. The skeleton of Lubomirskia baicalensis, which attains a size of up to 1 m, is constructed from spicules, which are cemented into longitudinal bundles. Our X-ray analysis revealed that the architecture of the specimens follows a highly ordered radiate accretive growth pattern. The spicules have a central axial canal with an axial filament inside. This organic filament is composed of silicatein, the major enzyme involved in silica formation of the spicules. We found that the specific activity of silicatein in samples from the non-growing (basal) zone is much lower than in those from the growth zone (tips) and that even the composition of this molecule differs in these regions. The present study shows for the first time that the turnover of silicatein, the major element of the axial canal of sponge spicules, changes within a sponge specimen depending on the region in which it is found.  相似文献   
104.
Measurements of the variation of the carbon dioxide partial pressure in water were performed up to pCO2 and CO2 using 6.000 ppm. The consistent data so far obtained were compared with calculated pCO2 using the Lynan constants. A plot of the experimental and calculated data evidences that comparisons are only possible by using varying carbonate alkalinity.  相似文献   
105.
Water contaminants have a high potential risk for the health of populations. Protection from toxic effects of environmental water pollutants primarily involves considering the mechanism of low level toxicity and likely biological effects in organisms who live in these polluted waters. The biomarkers assessment of oxidative stress and metabolic alterations to cadmium exposure were evaluated in Nile tilapia, Oreochromis niloticus. The fish were exposed to 0.35, 0.75, 1.5, and 3.0 mg/l concentrations of Cd2+ (CdCl2) in water for 60 days. Fish that survived cadmium exposure showed a metabolic shift and a compensatory development for maintenance of the body weight gain. We observed a decreased glycogen content and decreased glucose uptake in white muscle. Lactate dehydrogenase (LDH) and creatine phosphokinase (CK) activities were also decreased, indicating that the glycolytic capacity was decreased in this tissue. No alterations were observed in total protein content in white muscle due to cadmium exposure suggesting a metabolic shift of carbohydrate metabolism to maintenance of the muscle protein reserve. There was an increase in glucose uptake, CK increased activity, and a clear increase of LDH activity in red muscle of fish with cadmium exposure. Since no alterations were observed in lipoperoxide concentration, while antioxidant enzymes glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD) were changed in the liver and the red and white muscle of fish with cadmium exposure, we can conclude that oxygen free radicals are produced as a mediator of cadmium toxicity. Resistance development is related with increased activities of antioxidant enzymes, which were important in the protection against cadmium damage, inhibiting lipoperoxide formation.  相似文献   
106.
107.
It has been proposed that blue colouration in eggs has evolved as a signal of female quality that males can use to modulate their parental investment. This hypothesis is based in the antioxidant properties of biliverdin whose costly deposition in the eggshell is expected to signal female antioxidant capacity and egg quality. Since maternally derived androgens are costly to produce and may adaptively affect offspring phenotype, high-quality females may benefit by signalling their androgen investment through egg colouration. Our aim was to investigate whether egg colour variation in the spotless starling reflected the amount of pigments on the eggshell and whether egg pigmentation was related to female and egg quality. Chromatography analyses revealed that spotless starling eggshells contained two different pigments: biliverdin and protoporphyrin IX with no correlation between them. Biliverdin contents correlated positively with egg colouration indicating that darker eggs with a higher peak in the blue–green segment of the spectrum contained higher amounts of biliverdin. Eggs containing more biliverdin were laid by high-quality females and contained higher yolk testosterone levels. However, despite the strong correlation between biliverdin and colorimetric variables, egg colouration did not reflect accurately female and egg quality. Our results provide evidence that eggshell pigmentation in the spotless starling is related to female and egg quality as shown by the yolk testosterone levels. However, the lack of relation between egg colour and female condition and egg quality do not provide evidence to support the signalling function of egg colouration.  相似文献   
108.
This study investigates the relationship between the power of innovation and the sustainability strategies of companies involved in the minerals extraction sector in Brazil. The study included companies associated with the Brazilian Mining Institute, and it used research surveys to gather data. Analysis of the survey data revealed that companies with highly intensive characteristics in regard to innovation and environmental activities (environmental management activities) also display offensive, or proactive, strategies for pursuing sustainability.  相似文献   
109.
The recycling of municipal solid waste has a remarkable importance in the preservation of the environment and the welfare of the society. However, it is also important that this service can be provided with efficient costs. This paper aims to search for economies of output density and economies of size in the selective collection and recycling activities in Portugal and to identify the size the utilities should have to become more cost efficient. The sample comprises all Portuguese recycling utilities operating in the wholesale segment in the period 2006–2010. The results show that the Portuguese recycling utilities should increase the quantities of municipal solid waste for recycling (especially glass and paper) and also become larger to dimensions corresponding to a supply of 400–550 thousand inhabitants. With the increasing amount of glass collected, utilities are simultaneously struggling to fulfill the targets established by the European legislation and explore the existing economies of output density. The results also show that the management of these services carried out by private companies and the use of incineration (by utilities) seem to reduce the costs of utilities while the regulation of these services and the composting of waste held by utilities tend to increase costs.  相似文献   
110.
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