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191.
192.
This article analyzes the combined effects of stakeholder pressure and the implementation of environmental management systems on organizations’ environmental behaviors. Beyond their individual effects, the implementation of an environmental management system should enhance the effect of stakeholder pressure on environmental imbalance, defined as the divergence between what the organization does and what it should do. Information collected from 3748 industrial plants in seven countries provides empirical evidence that supports the study propositions. Therefore, this study contributes to both the debate about the effectiveness of environmental management systems and the effort to explain the complex relationship between organizations and their stakeholders in environmental matters.  相似文献   
193.
Parasites are undoubtedly a biotic factor that produces stress. Heat shock proteins (HSPs) are important molecules buffering cellular damage under adverse conditions. During the breeding season, blue tit Cyanistes caeruleus (L.) adults are affected by blood parasites, nest-dwelling parasites and biting flies, potentially affecting their HSP-mediated responses. Here, we treated females with primaquine to reduce blood parasites and fumigated nests with permethrin to reduce nest-dwelling parasites to test whether these treatments affect HSP60 level during the breeding season. Medicated females, but not controls, had a significant reduction of the intensity of infection by Haemoproteus spp. blood parasites. However, final intensity of infection did not differ significantly between groups, and we did not find an effect of medication on change in HSP60 level. Fumigation reduced the abundance of nest-dwelling parasites (mites, fleas and blowfly larvae) and engorged biting midges in nests. Females breeding in non-fumigated nests increased HSP60 levels during the season more than those breeding in fumigated nests. Furthermore, the change in HSP60 level was positively correlated with the abundance of biting midges. These results show how infections by nest ectoparasites during the breeding period can increase the level of HSPs and suggest that biting midges impose physiological costs on breeding female blue tits. Although plausible, the alternative that biting midges prefer to feed on more stressed birds is poorly supported by previous studies.  相似文献   
194.
Here, we provide evidence for a wavelength-dependent effect of light on magnetic compass orientation in Pelophylax perezi (order Anura), similar to that observed in Rana catesbeiana (order Anura) and Notophthalmus viridescens (order Urodela), and confirm for the first time in an anuran amphibian that a 90° shift in the direction of magnetic compass orientation under long-wavelength light (≥500 nm) is due to a direct effect of light on the underlying magnetoreception mechanism. Although magnetic compass orientation in other animals (e.g., birds and some insects) has been shown to be influenced by the wavelength and/or intensity of light, these two amphibian orders are the only taxa for which there is direct evidence that the magnetic compass is light-dependent. The remarkable similarities in the light-dependent magnetic compasses of anurans and urodeles, which have evolved as separate clades for at least 250 million years, suggest that the light-dependent magnetoreception mechanism is likely to have evolved in the common ancestor of the Lissamphibia (Early Permian, ~294 million years) and, possibly, much earlier. Also, we discuss a number of similarities between the functional properties of the light-dependent magnetic compass in amphibians and blue light-dependent responses to magnetic stimuli in Drosophila melanogaster, which suggest that the wavelength-dependent 90° shift in amphibians may be due to light activation of different redox forms of a cryptochrome photopigment. Finally, we relate these findings to earlier studies showing that the pineal organ of newts is the site of the light-dependent magnetic compass and recent neurophysiological evidence showing magnetic field sensitivity in the frog frontal organ (an outgrowth of the pineal).  相似文献   
195.
In recent years, the concept of sustainable development (SD) has become increasingly recognized and important. Within organizations, SD is often portrayed as a balancing act and requires a combination of three elements to be considered: economy, environment, and society. Traditionally, organizational management research has been focused on economical and environmental fronts. However, social aspects are also important for organizations, especially those in emerging and developing countries. The goal of this article is to investigate the potential of Clean Development Mechanism (CDM) projects to deliver social benefits in Brazil’s hydroelectricity sector. The investigation involved the assessment of 46 registered hydro CDM projects under the Kyoto Protocol in terms of their potential impact on the envisaged social development goals. Two case studies were also examined. Results indicate that organizations managing hydroelectric initiatives in Brazil can provide the pathway toward achieving a number of important social benefits. Successful projects were found to have good community involvement and were managed by both cooperative ventures and money-making corporations. The research also identified several challenges that are hindering hydro CDM projects from delivering more social benefits and enabled a number of recommendations to be extracted for the organizations facing these challenges.  相似文献   
196.
Exposure to uranium (U) is an occupational hazard to workers who continually handle it and an environmental risk to the population at large. Adverse effects of U on different tissues, particularly kidneys, have been reported. The aim of the present study was to investigate whether U might produce damage to the rat submandibular gland (SMG). Uranyl nitrate (UN) was used to evaluate the secretory responses to norepinephrine (NE) or to the parasympathomimetic agent, methacholine (MC), along with some morphological and histological parameters. In addition, the presence of U in saliva was determined by atomic absorption spectrometric techniques. Results indicate that intraperitoneal (i.p.) injection of a single dose of UN (2 or 4 mg kg?1) induced a functional decrease in the induced secretory responses in the rat SMG, demonstrating for the first time that U interferes with salivary secretion. Moreover, salivary responses to MC as well as to NE were decreased after UN administration, in time- and dose-dependent manner, displaying a higher diminution after 7 days post injection. In agreement with the functional studies, the injection of UN produced morphological alterations of SMG, consisting in a reduction of mean acinar area and a marked vacuolization. Data indicate that UN produced an adverse effect in a dose- and time-dependent manner on SMG function and morphology. Furthermore, it was shown that U was incorporated in saliva and therefore, these findings may contribute to create a useful, noninvasive method to detect the exposure to U.  相似文献   
197.
This paper aims to present the relevant results of a Life Cycle Assessment (LCA) study conducted on printed matter under a sheet-fed offset printing process by a company located in northwestern Mexico. Different scenarios were simulated in order to support decisions related to the improvement of environmental performance along the production processes. The study design was based on the European Platform on Life Cycle Assessment (EPLCA), which is in line with the ISO 14040 and 14044:2006 standards on LCA. The scope of the study was cradle-to-gate, with emphasis on the production of printed matter. The method chosen for the impact assessment was Impact 2002+ with a combined midpoint–damage approach. The results of the study showed that the major contributors to adverse effects were, primarily electricity consumption followed by paper consumption during the printing operation, as well as consumption of ink to a small degree. As for the plate-making operation along with the generation of secondary products, the result was negative. This is essentially due to involvement of recyclable materials, thus contributing to the prevention of raw material extraction. The smallest impact was observed from processes involving cleaning products and LP gas. The main issues of concern stemming from the results are electricity consumption and printing – both activities dominate almost all the midpoint categories. Generation of secondary products also had a relative environmental impact along the supply chain. Cleaning agents and LP gas did not have a significant impact on the final results of the process.  相似文献   
198.
Visual displays are signals that may be selected to increase visibility. Light is a crucial component in the transmission of visual signals, and white colour is very conspicuous when illuminated by sun and exhibited against darker backgrounds. Here we tested the hypothesis that orientation of sexual displays in male great bustard (Otis tarda) depends upon position of the sun, i.e., males direct their uplifted white tails towards the sun in order to maximise signal detectability to distant females. We recorded the orientation of 405 male displays in relation to the sun and to females at seven leks. Great bustard males signalled towards the sun more often than expected by chance in early morning, although this pattern was not obvious at other times of day, when males displayed more towards females. Our hypothesis was further supported by the fact that displays were more directed towards the sun when the sun was most visible. Males were more likely to direct their displays towards females during the most elaborate components of their courtship display and when there were fewer males on the lek. Pointing white plumage to the sun may be a behaviour selected in species living in steppe-like open landscapes if individuals obtain net fitness benefit by increasing the likelihood of mating.  相似文献   
199.
In this article, a life cycle assessment approach is used to carry out a preliminary assessment of the environmental and energy performance of a specific chemical recycling and recovery system that supplies a variety of petrochemical blendstocks through the sequential pyrolysis and catalytic reforming of plastic wastes. Characterization results are presented for a selection of seven impact categories: abiotic depletion, global warming, acidification, eutrophication, ozone layer depletion, photochemical oxidant formation and cumulative non-renewable energy demand. From a combined environmental and energy perspective, the results suggest the suitability of this system for plastic waste valorization. However, improvement actions aimed at reducing the thermal energy demand and mitigating direct emissions to the air should be undertaken. Furthermore, the environmental profiles of the proposed petrochemical blendstocks are compared with those of conventional energy products. A comparison among this chemical recycling and recovery system and two conventional management practices (municipal incineration and landfilling) is also addressed. The results show that the considered system could entail relevant environmental and energy benefits when compared to conventional energy systems and waste management strategies.  相似文献   
200.
From an international view, several papers have analysed how sustainability themes are integrated into the university curricula. In Spain, few studies to date have examined the extent to which universities are incorporating sustainability themes into their curricula. In view of such considerations, this article examines the extent to which sustainability themes are being incorporated into the curricula of a Spanish public university strongly committed to signing sustainability policies and declarations. In addition, this study analyses the main barriers to the incorporation of sustainability themes into the curricula of this university. To accomplish this task, this article uses different methodological instruments over three phases through a case study approach. The findings of this study suggest how the university examined has many difficulties in incorporating, holistically or separately, sustainability themes in its formal courses despite having so many policies, regulations and a commitment to sustainability.  相似文献   
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