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181.
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
182.
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
183.
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
184.
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
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Mendel Z Dunkelblum E Branco M Franco JC Kurosawa S Mori K 《Die Naturwissenschaften》2003,90(7):313-317
The biological activity of the Matsucoccus spp. sex pheromones and diene modified analogs has been tested in forests of Israel and Portugal in order to explore the structure-activity relationship of the pine bast scale pheromone/kairomone system. The response of the adult predatory bugs, Elatophilus hebraicus and E. crassicornis and of the brown lacewing, Hemerobius stigma is more selective than that of the conspecific Matsucoccus males. The removal of the terminal methyl group from the diene terminus of both pheromones 1 and 2 eliminates all kairomonal activity but retains moderate pheromonal activity. Addition of a methyl group to the diene terminus of pheromones 1 and 2 sustains full pheromonal and kairomonal activities of the Elatophilus spp. but eliminates entirely the kairomonal activity of H. stigma. Subtle designed alterations in the structure of the diene group, typical of all Matsucoccus pheromones, change the mode of the kairomonal activity markedly. 相似文献
188.
Land use as a mitigation strategy for the water-quality impacts of global warming: a scenario analysis on two watersheds in the Ohio River Basin 总被引:4,自引:0,他引:4
This study uses an integrative approach to study the water-quality impacts of future global climate and land-use changes. In this study, changing land-use types was used as a mitigation strategy to reduce the adverse impacts of global climate change on water resources. The climate scenarios were based on projections made by the Intergovernmental Panel on Climate Change (IPCC) and the United Kingdom Hadley Centre's climate model (HadCM2). The Thornthwaite water-balance model was coupled with a land-use model (L-THIA) to investigate the hydrologic effects of future climate and land-use changes in the Ohio River Basin. The land-use model is based on the Soil Conservation Service's curve-number method. It uses the curve number, an index of land use and soil type, to calculate runoff volume and depth. The ArcView programming language, Avenue, was used to integrate the two models into a geographic information system (GIS). An output of the water-balance model, daily precipitation values adjusted for potential evapotranspiration, served as one of the inputs into the land-use model. Two watersheds were used in the present study: one containing the city of Cincinnati on the main stem of the Ohio River, and one containing the city of Columbus on a tributary of the Ohio River. These cities represent two major metropolitan areas in the Ohio River Basin with different land uses experiencing different rates of population growth. The projected hypothetical land-use changes were based on linear extrapolations of current population data. Results of the analyses indicate that conversion from agricultural land use to low-density residential land use may decrease the amount of surface runoff. The land-use practices which generate the least amount of runoff are forest, low-density residential, and agriculture; whereas high-density residential and commercial land-use types produce the highest runoff. The hydrologic soil type present was also an important factor in determining the amount of runoff and non-point-source pollution. A runoff-depth matrix and total nitrogen matrix were created for Cincinnati and Columbus to describe possible land-use mitigation measures in response to global climate change. The differences in Cincinnati and Columbus were due to differences in geographic location, air temperature, and total runoff. The results of this study may be useful to planners and policy makers for defining the possible impacts of future global climate and land-use changes on water resources. 相似文献
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