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81.
The Abt study of forty-one mostly Fortune 200 nonservice firms forms a new picture of environmental management. We present data indicating that environmental management is becoming central to corporate strategy and is being managed as an arena of competition rather than as a compliance-driven function. We look at environmental management's new role through four lenses: its relationship to strategic planning; its evolving management structures that show environment increasingly integrated into the main functions of the business; innovation in corporate environmental investments reflecting new drivers beyond compliance; and new management systems and measures of firm-wide performance that demonstrate that environment is being seen increasingly as an arena of competitive concern. We argue that much of the change is driven by three realities. First, as customers integrate environmental values into their conceptions of product quality, they are buying more products with identifiably environmental attributes. This change translates environmental management, historically a cost center, into a potential source of sales revenue, a change which cannot be underestimated. Second, recent life-threatening damage to the global ecosystem and atmosphere reframes environmental management. This moves firms toward a systemic and global approach matched to the globalization of competitive and market concerns, and it places environmental management in the strategic sphere. And third, pollution prevention in its cross-fertilization with total quality management is driving firms to focus on managing environment as an integral part of product management, and is helping them to reassess environmental performance as a contributor to productivity and innovation.  相似文献   
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Summary Mother-calf whistle exchanges were recorded from temporarily captured free-ranging bottlenose dolphins from 1975 to 1989. This is part of a long-term research project studying social structure and behavior of a community of approximately 100 dolphins in waters near Sarasota, Florida. Analysis of whistle exchanges from 12 mothercalf pairs shows that signature whistles can remain stable for periods up to at least 12 years. We looked for effects of vocal learning on the development of the signature whistle by comparing whistles of calves to those of their mothers. Eight female calves produced whistles distinct from those of their mothers, while four male calves produced whistles similar to those of their mothers. Male calves appeared to produce a greater proportion of whistles other than the signature whistle (termed variants). We hypothesize that these sex differences in whistle vocalizations may reflect differences in the roles males and females play in the social structure of the community.  相似文献   
83.
The signature whistle hypothesis states that dolphins produce highly stereotyped, individually distinctive whistles when in isolation. The presence of signature whistles has been called into question by recent studies proposing that dolphins produce a shared, simple upsweep whistle when in isolation, and that whistles produced by socializing dolphins are shared across individuals and social groups. This shared repertoire hypothesis suggests that when two animals produce the same whistle type, it is due to sharing the same common repertoire rather than one animal learning to produce the whistle of another. One difference between studies supporting or denying the existence of signature whistles is the method used to classify whistle types. We examined whistle production by 17 free-ranging bottlenose dolphins while temporarily restrained. We used both a quantitative comparison technique similar to that used to support the shared repertoire hypothesis and human judges to classify whistle types and quantify similarity between types. Contrary to recent studies that emphasize shared whistles, overall whistle sharing between isolated individuals was low (25%) and a simple upsweep did not account for the most common whistle type in half of the animals. Some species of birds, bats, and primates with stable social groups use vocal learning to converge over time to one common group distinctive call type. We examined whistle similarity between adult male dolphins that are partners in a close social alliance in order to test whether vocal learning may enable a similar vocal convergence. Whistle similarity was rated very high between partners and low between non-partners by both the quantitative technique and human observers. This suggests that as in songbirds and some other mammals, adult male bottlenose dolphins may use vocal learning to converge on similar whistles as they develop affiliative social relationships.Communicated by G. Wilkinson  相似文献   
84.
In the terrestrial environment, standardized protocols are available for measuring the exposure and effects of contaminants to invertebrates, but none currently exist for vertebrates. In an effort to address this, we proposed that developing lizard embryos may be used as a terrestrial vertebrate model. Lizard eggs may be particularly susceptible to soil contamination and in ovo exposure may affect hatchling size, mortality, as well as thyroid function. Toxicant-induced perturbations of thyroid function resulting from in ovo chemical exposure may result in toxicity during the critical perinatal period in reptiles. Fertilized Eastern fence lizard (Sceloporus undulatus) eggs were placed in cadmium (Cd)-spiked expanded perlite (0, 1.48, 14.8, 148, 1480, 14 800 μg Cd/g, nominal concentrations), artificially incubated at 28 °C, and examined daily for mortality. Whole lizard hatchlings as well as failed hatches were homogenized in ethanol and the homogenate was divided for Cd body residue analysis and thyroid hormone (triiodothyronine (T3) and thyroxine (T4)) analyses. Acute mortality was observed in the two highest doses (1480 and 14 800 μg Cd/g). Cadmium body residues showed a higher internal concentration with increasing exposure concentration indicating uptake of Cd. There was a decrease in T3:T4 ratio at the highest surviving dose (148 μg Cd/g), however, there were no differences observed in hatchling size measured as weight and snout-vent length, or in whole body thyroid hormone levels. In summary, this study has shown Cd amended to a solid phase representing soil (perlite) can traverse the thin, parchment-like shell membrane of the fence lizard egg and bioaccumulate in lizard embryos. We believe this study is a good first step in investigating and evaluating this species for use as a model.  相似文献   
85.
Scanning electron microscopy, surface area determination, elemental analysis, organic matter extraction and solid-state cross polarization/magic angle spinning and Bloch decay/magic angle spinning 13C nuclear magnetic resonance (NMR) spectroscopy were used to investigate distinctive features among carbonaceous combustion residues. Black carbon (BC) samples included diesel soot, urban dust, carbon black, chimney soot, vegetation fire residues, wood and straw charcoals. Particles varied from small spheres (<50 nm) in fossil BC (>100 m(2)/g), to large layered structures in plant-derived BC (generally <8 m(2)/g). Chimney soot also included large (>1 micrometer) liquid-like structures, while spherules >100 nm were unique to urban dust. The ratios of amorphous to soot carbon (SC) (isolated by thermal degradation) were not necessarily correlated with the degree of aromaticity estimated from H/C ratios. In particular, values of SC in diesel soot were clearly overestimated. Solvent-extractable organic matter (SEOM) was <2% for charcoals and carbon black, but >13% for urban dust, chimney and diesel soot. SEOM is thought to clog pores or to form large waxy globules, hence reducing surface areas. The ratio of polar/nonpolar SEOM was generally <7 for fossil BC, but >30 for plant-derived BC. NMR analysis revealed essentially one chemical shift in the aromatic C region of charcoals, while diesel soot also showed important aliphatic contributions. Aliphatic and oxygenated C predominated over aryl C in urban dust and chimney soot. These morphological and chemical characteristics of the BC samples are discussed in terms of their environmental implications.  相似文献   
86.
Environmental pollution with polycyclic aromatic hydrocarbons (PAHs) from pyrogenic or petrochemical sources is a matter of concern in many aquatic ecosystems. For field monitoring purposes, PAH metabolite levels in fish bile samples can be used as biomarkers of exposure, but previously there were no reference materials for analytical method validation or quality control. In this paper we describe the preparation and certification of two fish bile materials. BCR 720 is a pure bile material from sediment-exposed flounder (Platichthys flesus) and BCR 721 is a pure bile material from oil-exposed plaice (Pleuronectes platessa). Homogeneity and stability tests were carried out and a group of 12 expert laboratories was assembled for the certification measurements. The methods applied were liquid chromatography with fluorescence detection or gas chromatography with mass spectrometric detection. In BCR 720 three PAH metabolites were certified: 1-hydroxyphenanthrene, 1-hydroxypyrene and 3-hydroxybenzo[a]pyrene. In BCR 721 1-hydroxypyrene was certified. The fourth target compound, 2-hydroxynaphthalene, could not be certified, but the results obtained are listed. The major findings from earlier feasibility studies and recommendations for the optimal use of the reference materials are also included.  相似文献   
87.
Integrating protected area management with local needs and aspirations   总被引:4,自引:0,他引:4  
Wells MP  McShane TO 《Ambio》2004,33(8):513-519
Conservationists recognize that many protected areas have limited future prospects without the cooperation and support of local people, especially in developing countries. Since the 1980s Integrated Conservation and Development Projects (ICDPs) have attempted to reconcile park management with local needs and aspirations, usually with disappointing results. Achieving local cooperation and support without jeopardizing conservation goals remains a top priority for parks, however. Fortunately, the lessons from the ICDP experience provide an important opportunity to inform the next generation of biodiversity conservation programs, including those concerned with poverty alleviation as well as those working at ecosystem and landscape scales. More recent and more promising approaches have started to incorporate elements of adaptive management, new partnership models with stakeholders and the vertical integration of site-level work with policy initiatives and institutional development.  相似文献   
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There is increasing interest in the use of preimplantation genetic diagnosis (PGD) as an alternative to routine prenatal diagnosis. However, the costs associated with development and testing of new PGD protocols have forced some PGD centres to limit the number of diseases for which PGD is offered. One of the main factors in the design of new protocols, which affects cost and accuracy, is the choice of the mutation-detection technique. We have assessed the reliability of DNA sequencing and mini-sequencing for clinical diagnosis at the single-cell level and have found them to be rapid and accurate. Extensive optimisation for individual mutations is not usually necessary when employing these versatile techniques and consequently a smaller investment of time and resources should be required during development of new protocols. Additionally, we report single-cell protocols for the diagnoses of cystic fibrosis, sickle cell anaemia and β-thalassaemia, which utilise mini-sequencing. Unlike most mutation-detection techniques, mini-sequencing permits analysis of very small DNA fragments. Small amplicons experience low allele dropout (ADO) rates, and consequently this approach could potentially improve the reliability of PGD. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
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