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931.
The purpose of this research is to analyze different factors behind the disclosure of corporate information on issues related to opportunities arising from climate change worldwide.To achieve that purpose we formulated a dependency model in which the dependent variable corresponds to the creation of a disclosure index on greenhouse gas emissions based on the opportunities arising from climate change and disclosed by companies on their websites. The sample used comprises companies from different countries and activity sectors considered as the most sensitive to greenhouse gas emissions.The results obtained point out that companies with higher environmental performance disclose a larger volume of information on opportunities arising from climate change on their websites, compared to companies with lower environmental performance. Likewise, companies from countries that have ratified the Kyoto Protocol disclose a higher volume of information on greenhouse gas emissions on their websites, compared to companies from countries which have not ratified it.  相似文献   
932.
New waste management programs are currently aimed at developing alternative treatment technologies such as mechanical–biological treatment (MBT) and composting plants. However, there is still a high uncertainty concerning the chemical and microbiological risks for human health, not only for workers of these facilities, but also for the population living in the neighborhood. A new MBT plant is planned to be constructed adjacently to a municipal solid waste incinerator (MSWI) in Tarragona (Catalonia, Spain). In order to evaluate its potential impact and to differentiate the impacts of MSWI from those of the MBT when the latter is operative, a pre-operational survey was initiated by determining the concentrations of 20 volatile organic compounds (VOCs) and bioaerosols (total bacteria, Gram-negative bacteria, fungi and Aspergillus fumigatus) in airborne samples around the MSWI. The results indicated that the current concentrations of bioaerosols (ranges: 382–3882, 18–790, 44–926, and <1–7 CFU/m3 for fungi at 25 °C, fungi at 37 °C, total bacteria, and Gram-negative bacteria, respectively) and VOCs (ranging from 0.9 to 121.2 μg/m3) are very low in comparison to reported levels in indoor and outdoor air in composting and MBT plants, as well in urban and industrial zones. With the exception of total bacteria, no correlations were observed between the environmental concentrations of biological agents and the direction/distance from the facility. However, total bacteria presented significantly higher levels downwind. Moreover, a non-significant increase of VOCs was detected in sites closer to the incinerator, which means that the MSWI could have a very minor impact on the surrounding environment.  相似文献   
933.
The total ozone monthly means derived from measurements by the Dobson spectrophotometer at Belsk (52°N, 21°E) and satellite observations over central and midlatitudinal Europe are analyzed for the long-term changes between 1995 and 2008. Standard explanatory variables representing physical and chemical processes known to influence the ozone distribution are considered. The potential proxies are: atmospheric loading by the ozone depleting substances characterized by the equivalent effective stratospheric chlorine (EESC) time series, various drivers of ozone dynamical variability including solar cycle, teleconnection patterns, temperature at 50 hPa, and pressure at the tropopause level. The multivariate adaptive regression splines (MARS) methodology is used to find optimal set of the explanatory variables and shape of the anthropogenic trend curve. Following options for the trend curve are examined: proportional to EESC, piecewise linear (with the turning points in 1980 and 1995), and selected from a smooth curve fit to the total ozone time series having “natural variations” removed. Statistical estimates and their uncertainties are calculated using block bootstrapping. The analyses indicate that ozone over Belsk, in central Europe, and in midlatitudinal Europe reaches at least first stage of recovery as defined by the World Meteorological Organization: a statistically significant reduction in the rate of decline. Model using the EESC time series as a proxy for the anthropogenic trend pattern yields even the second stage, i.e., a positive trend in time series that remains after removal dynamical signal from the analyzed data. Substantial seasonal dependent long-term ozone oscillations by the dynamical drivers are revealed causing estimation of the ozone recovery time even more uncertain.  相似文献   
934.
The honeybee Apis mellifera has evolved in different environments and has developed different ecotypes. The objective of the Honeybee Genetic program in Argentina (MeGA) is to select honeybees adapted to different regions in the country using an important number of colonies as base population. In the last years, morphometric analyses are being incorporated into the Program as a tool for characterization of genetic materials; this fact has motivated the present work. A random sample of honeybee workers (250) was taken from 30 colonies situated in different regions in the country. The proboscis, right hind leg, right forewing and hind wing were placed on a slide and the following variables were measured: length and width of forewing and hind wing, different angles and length of wing veins, the length of the tibia, femur and metatarsi, the width of the metatarsi and the length of the proboscis. Thirty morphometrical variables were analyzed and the distribution and relation between them were recorded.  相似文献   
935.
As sustainability considerations increasingly dominate the technology development debate worldwide, practical approaches to assess environmental performance of innovations have been warranted. The present study (Part 1) introduces Ambitec-Life Cycle, a method derived from Ambitec-Agro for considering life cycle thinking in the environmental performance evaluation (EPE) of agro-industrial innovations. An agro-industrial innovation case study related to residue recycling is presented, revealing steps in the product life cycle where opportunities are best for technological improvements. In Part 2 (this issue) of this study, a methodological approach for considering the environmental vulnerability of watersheds and to integrate this analysis in EPE methods is presented. This approach is applied to Ambitec-Life Cycle and to the same residue case study, allowing the identification of performance indicators with greater potential to cause impacts at the studied watersheds.  相似文献   
936.
937.
This study investigates whether a consistent relationship exists between computerization and job control. It also examines the role of job control as a predictor of stress symptoms typical for data entry and word processing (VDU) work. Two groups of VDU users and two comparable non-VDU-user groups took part in this study. A special questionnaire made it possible to assess global job control and four indexes of control related to specific aspects of work (control over choice of tasks and methods, control over time frame, control related to one’s skill, and control related to participation in the decision-making process). Results did not show an unequivocal relation between computerization and the latitude of control. The latitude of control depends on the task performed and the aspect of control we are considering. Regression analyses showed that global control is a good predictor of job satisfaction, some mood disturbances, and visual complaints. The other aspects of control are related in a variety of ways to stress symptoms. The role of a Type A behavior pattern in the relationship between job control and stress symptoms varies depending on which aspect of control is being considered. It was concluded that because of the high functional differences between various aspects of control, it is better to avoid using the concept of global control and, when possible, apply specific indexes of control.  相似文献   
938.
EC Directive 2008/50/CE on ambient air quality and cleaner air for Europe specifies the obligations of Member States regarding fixed measurements of atmospheric pollutants in areas where maximum concentration levels exceed the lower assessment threshold. However, indications as to the siting of atmospheric monitoring stations are less precise and sometimes confusing. Campaigns to measure benzene and other volatile organic compounds in Murcia in 2007 and 2008 revealed that the areas where measurements coincided with the mean concentration for the whole city were always practically the same. Consequently, we propose a method for siting atmospheric monitoring stations in cities for which emission sources remain steady throughout the year, as is the case for cities in most southern European countries, where the most important emission source is traffic. The method is particularly useful for towns in which only one fixed measuring point is compulsory and should help local authorities in making correct decisions in this context.  相似文献   
939.
The effects of pesticides (a herbicide and a fungicide) on the microbial community structure and their activity were analyzed in soil from four alpine pasture grasslands in Slovakia. Specifically, the effects of the herbicide, Gesagard (prometryn active ingredient), and fungicide, Fundazol 50 WP (benomyl active ingredient), on the microbial respiration activity (CO2 production), the numbers of selective microbial physiological groups (CFU.g?1) and the structure (relative abundance) of soil microbial communities [(phospholipid fatty acid (PLFA)] were analyzed under controlled laboratory conditions. All treatments including the treatments with pesticides increased (statistically significantly) the production of CO2 in all fields during 21 days of incubation and posed a statistically insignificant negative influence on the numbers of the observed physiological groups of microorganisms. The significantly negative influence was evaluated only in the numbers of two physiological groups; spores of bacteria utilizing organic nitrogen and bacteria, and their spores utilizing inorganic nitrogen. A shift in the microbial composition was evident when the PLFA patterns of samples from different sites and treatments were compared by the Principal Component Analysis (PCA). According to the second component PCA 2 (15.95 %) the locations were grouped into two clusters. The first one involved the Donovaly and Dubakovo sites and the second one contained the Velka Fatra and Mala Fatra locations. The PLFA composition of the soils showed important changes after the treatment with pesticides according to PCA 1 (66.06 %). Other treatments had not had a significant effect on the soil microbial community with the exception of the population of fungi. The lower relative abundance (significant effect) of Gram-positive bacteria, actinomycetes and general group of bacteria were determined in samples treated by the herbicide Gesagard. The application of fungicide Fundazol decreased (statistically significantly) the relative abundance of actinomycetes and general group of bacteria and paradoxically increased the population of fungi.  相似文献   
940.
The introduction of genetically modified plants into the environment has been marked by different positions, either in favor of or against their release. However, the problem goes well beyond such contradictory positions; it is necessary to take into account the legislation, ethics, biosafety, and the environment in the considerations related to the release of genetically modified organisms (GMOs). To this end, the Brazilian Committee of Biosafety (CTNBio), a consultative and deliberative multidisciplinary collegiate, provides technical and advisory support to the Brazilian Federal Government. This committee consists of scientists and non-scientists who participate in evaluating the dossiers of companies that are requesting approval by the Brazilian Government; consequently, the aim of this study was to investigate whether commercial approvals of GMOs were associated with the profile of the CTNBio members. Research was based on the minutes taken at CTNBio meetings carried out from 2006 up to 2009, considering law 11.105/2005 and the Constitution of 1988 as legal frameworks, to determine the number of voters in favor of or against releasing genetically modified Bt-maize, Bt-cotton, and herbicide resistant soybeans to be used in Brazilian agriculture. Via the internet, we had access to the curriculum vitae of the CTNBio members through the Plataforma Lattes database of the National Council for Scientific and Technological Development (CNPq), where we found their area of expertise. CTNBio members were divided into expert-for, expert-against, non-expert-for, and non-expert-against. Results showed that CTNBio decisions could be based on technical criteria as well as on the policy of the institution that expert-members were representing.  相似文献   
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