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291.
Pelgrom SM Lamers LP Lock RA Balm PH Bonga SE 《Environmental pollution (Barking, Essex : 1987)》1995,90(3):415-423
Sexually mature female tilapia were exposed to sublethal concentrations of waterborne Cu and/or Cd over 6 days, and subsequent body concentrations of these metals were determined in several organs. The results show that the distribution of Cu and Cd was metal and organ specific. This is demonstrated, for example, by the observation that in tilapia, Cu exposure did not result in Cu accumulation in the liver, whereas in the intestinal wall, notably high concentrations of Cu and Cd were measured in metal exposed fish. In addition to single metal exposed fish, we also determined Cu and Cd body distribution in Cu?Cd co-exposed fish. The observed interactions in metal accumulation were most pronounced in the organs of fish exposed to low, environmentally realistic, metal concentrations. 相似文献
292.
Bouhamra WS 《Environmental pollution (Barking, Essex : 1987)》1995,90(1):121-125
Interest in indoor air quality is steadily increasing. Exposure to volatile organic compounds (VOCs) is associated with health effects as diverse as childhood respiratory disease, lung cancer and cardiovascular disease. In an effort to assess the environmental impact indoors from possible sources of VOCs, such as (i) open oil lakes, (ii) chemical and petrochemical industries and (iii) indoor pollution from household items, concentrations of aliphatic and aromatic VOCs, comprising n-hexane to n-hexadecane, benzene, toluene, xylene, ethyl benzene, methanol and o-dichlorobenzene, were measured in indoor air samples from seven different cities in Kuwait using a gas chromatograph. The data for the period March to May 1993 are presented. The VOCs, as measured, were surprisingly low and they are below the concentrations set by the American Hygienists Association. However, although the concentration of the estimated VOCs being low, were cumulative effects of them entering the human body and water sources cannot be ruled out. 相似文献
293.
Dr. Martin F. Price 《The Environmentalist》1995,15(4):272-280
Summary Mountain regions comprise one-fifth of the world's land surface. They are home to a tenth and important in the lives of half of humankind. Yet mountains are often regarded as physically, politically and economically marginal; their importance has only recently been globally recognized. The potential impacts of climate change in mountain regions will vary considerably between different types of regions. These are briefly described, as an introduction to an evaluation of the potential impacts with regard to agriculture, forestry, water resources, tourism, energy, transport and health. It is concluded that climate change cannot be considered a marginal issue and that the ability of mountain and downstream people to adapt and respond in the long term will require attention to the maintenance and use of local knowledge and cooperative social networks, as well as considerable scientific research.Dr Martin Price obtained his Ph.D from the University of Colorado at Boulder, following a first degree at the University of Sheffield and an MSc from the University of Calgary, Canada. He is currently the Programme Leader for the Mountain Regions Programme at the Environmental Change Unit at the University of Oxford. This paper was presented at the Global Forum '94 Academic Conference and it represents a revision of an article by the author in Beniston (1994). 相似文献
294.
Summary The labelling of ecofriendly products has been introduced in a number of developed countries to assist in the protection of the environment. Recently, developing countries like India, have introduced the scheme. This paper examines the steps involved in establishing the Indian Ecomark. For the successful implementation of the scheme the effective coordination of a number of agencies is necessary. Consumers, as well as manufacturers, have to be educated in the longterm benefits of the scheme. Initiatives necessary for the successful implementation of Ecomark have been highlighted.Mr S. S. Arvind is a member of faculty at the Centre for Energy, Environment and Technology, at the Administrative Staff College of India. He is currently on secondment to the Centre for Technology Development, Clark University, 950, Main Street, Worcester MA 01610-1477, USA. Mr E.V. Muley is a scientist working for the Ministry of Environment and Forests, Government of India, Paryavaran Bhavan, CGO Complex, Lodi Road, New Delhi 110003, India. 相似文献
295.
A simple method of time series analysis, based upon linear least squares curve fitting, is developed. The method's advantages and disadvantages are discussed, and an example is presented using the Vostok Core methane record. 相似文献
296.
Protein that makes sense in the Argentine ant 总被引:1,自引:0,他引:1
With a protein-based approach, we have identified and cloned the cDNA encoding a chemosensory protein (LhumCSP) in the Argentine ant, Linepithema humile. The open reading frame of the cloned cDNA encoded a signal peptide (20 residues), and a mature protein (pI 4.62) of 106 amino acid residues. The calculated molecular mass (12,453 Da) was in agreement with the molecular mass measured by on-line chromatography-electrospray ionization mass spectrometry (12,448 Da), given the formation of two disulfide bridges. LhumCSP shared sequence similarity with various CSPs, particularly those identified and/or cloned from moth species. Also, LhumCSP showed the hallmark of the chemosensory proteins, i.e., four well conserved cysteine residues. The antennal protein was not detected in non-olfactory tissues (leg and thorax) contrary to a putative pheromone-binding protein isolated from the thorax of the red imported fire ant, Solenopsis invicta. In addition, these findings suggest that, as in Orthopterans and Phasmids, the protein that makes sense in the Argentine ant is not an odorant-binding protein, but rather a chemosensory protein. 相似文献
297.
J. Altenburger Th. Dielacher P. Eder H. Ferner M. Fegerl J. Fresner O. Gelinek A. Kogler J. Jantschgi M. Nussbaumer B. Russegger H. Schnitzer K. Schauer B. Sebesta J. Seiler F. Sprenger H. Widenmeyer 《Journal of Cleaner Production》1994,2(3-4)
The paper focuses upon the organization of a federal state-funded pollution prevention project in the Styrian industry. The project includes 13 companies from the textile, pulp and paper, machine building, wood working and printed circuit board manufacturing industries, covering most of the sectors and sizes in the Styrian industry. It started in January 1994 and will last for one year. It will demonstrate the possibilities of pollution prevention and the need for further research work. This project will make use of the methods and tools that were refined in the Austrian Prepare project. As a first step, a systematic balance of all the inputs and outputs of a company is made, after which the weak points and inefficiencies of material and energy use are identified and the options for improvements, both economical and ecological, are defined. Consequently, modifications in products and production lead to a situation with less waste and emissions. The preliminary lessons from these projects are presented: as a rule, the utilities (consumption of process materials and water, cleaning, energy, preparatory and finishing steps) are treated as black boxes and usually represent a considerable optimization potential. In these areas especially there is usually a lack of information and coordination as well as a need for a systematic and comprehensive approach. Leadership in the company and creative consultants are needed for starting lasting successful pollution prevention projects. 相似文献
298.
Part of the work was supported by the Bundesministerium für Forschung und Technologie, the Deutsche Forschungsgemeinschaft, the Fonds der Chemischen Industrie, and from the Carl Zeiss, Hoechst, and Ernst Leitz companies. Special thanks are due to Dr. K. Wahn, Department of Virology, University of Giessen, for conducting the electron microscope and phase-contrast investigations, to Prof. G. Sauer, German Cancer Research Center, Heidelberg, and Dr. W. R. Willems, Department of Medical Virology, University of Giessen, for supplying the different cell lines. 相似文献
299.
300.