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731.
A.M. Hegazy H.H. Bakry R.M. El-Shawarby M.E. Abou-Salem N.M. Abd El-Aleem 《毒物与环境化学》2013,95(1):136-145
This study was carried out to investigate the effect of long-term exposure to benzo(a)pyrene (B(a)P) in mice. Hemogram, tumor markers, oxidative status, and B(a)P residues in liver tissue were evaluated. Sixty albino Swiss mice were randomly distributed equally into three groups; the control was given 0.1?mL corn oil once a week for 8 weeks. The other two groups were given 20 and 40?mg B(a)P per kg body weight once a week orally for the same period. B(a)P-treated mice suffered from depression and ascites, and macrocytic normochromic anemia was recorded at the 16th and 30th week. There was marked leukocytosis with lymphocytosis at the early stage of the experiment, followed by leukopenia, lymphopenia, and neutropenia at the end of the experiment. Monocytes and arginase activity were elevated throughout the experiment. Alpha feto-protein was detected only in the experimental groups in the 30th week of the experiment. A marked increase in lipid peroxides associated with a decrease in reduced glutathione and glutathione-S-transferase (GST) activity was observed in liver homogenate of the B(a)P-exposed animals. Residues of B(a)P were detected in liver tissue with a concentration parallel to the B(a)P dose level. In conclusion, B(a)P caused abnormal changes in the hemogram, evidence of tumor formation through B(a)P-induced oxidative stress, and it was accumulated in the liver tissue of mice. 相似文献
732.
Marcelo de O. Milfont Epifania Emanuela M. Rocha Afonso Odério N. Lima Breno M. Freitas 《Environmental Chemistry Letters》2013,11(4):335-341
This is the first report showing that using honeybee (Apis mellifera) and wild pollinators complementary pollination can enhance soybean productivity (Glycine max). Current industrial production of soybean involves autopollination and high loads of pesticides. Therefore, growers have neglected possible biotic pollination despite suggestions that soybean benefit from insect pollinators. Reports advocating possible biotic pollination are based on experiments where bees are caged with flowering plants and the absence of pesticides, thus not in field conditions. Therefore, here we compared in field conditions soybean yield produced (1) independently of biotic pollinators, (2) with wild pollinators and (3) with honeybee colonies. Results showed an increase of +6.34 % of soybean yield in areas where wild pollinators had free access to flowers. The introduction of honeybee colonies further raised the yield of +18.09 %. Our findings therefore show that, though soybean is autogamous, allowing pollination by wild pollinators leads to higher yields. Moreover, adding honeybee mitigates pollination deficits and improves yield compared to current practices. 相似文献
733.
Long-term decadal retrospection in spatio-temporal imagery analyses can only be carried out using aerial photographs, which are still the most detailed remotely sensed data available. Visual interpretation of such imagery is most efficient and inexpensive in the light of ecosystem monitoring research in developing countries, which are often unable to cope with the development or the cost of acquisition of commercial space-borne imaging (e.g. IKONOS, Quickbird). In this light, the present paper explicitly analyses the methodological use of image attributes of air-borne imagery from mangrove forests, and investigates the consistency and constraints of mangrove image attributes in visually interpreted air-borne imagery. Six image attributes are analysed, and their application is illustrated using various mangrove sites in Kenya and Sri Lanka. Comparison of identification keys reveals that minor attributes such as 'ecological position' are informative, and that image attributes for a particular species or genus are apparently less plastic and more widely applicable than formerly assumed. Emphasis on compulsory fieldwork is made and constraints related to reflection and interference, amongst others, are discussed. 相似文献
734.
In this paper, we review three broad classes of indicators of sustainable development. These are economic, ecological and sociopolitical indicators. We then report the results of a pilot study which measured five different indicators for Scotland: an approximate environmentally-adjusted Net National Product; the Pearce-Atkinson Measure; Net Primary Production; Appropriated Carrying Capacity; and the Index of Sustainable Economic Welfare. We find that not all indicators point in the same direction, but a majority suggest that Scotland is at best only marginally sustainable. Data limitations, however, suggest a degree of caution in the interpretation of these results. 相似文献
735.
Brian G. Field Brian G. Field J. N.R. Jeffers R. J. Livingston Jonathan Cowie 《国际发展与全球生态学杂志》2013,20(1):85-90
The aim of sustainable development is to balance social, economic, and environmental needs. In order to justify the decisions they make, stakeholders must quantify the different impacts found in the operations and developments of companies and/or projects throughout their life cycle. However, as some areas are subjective in nature, the quantification process of the different impacts and the assessment of sustainable development performance become arduous tasks of development, validation, and application of scientific and empirical methods with the intrinsic objective of finding an agreement among the involved parties (i.e., stakeholders). Several environmental and sustainability assessment tools, instruments, processes, and methodologies have been developed; rating systems stand out and have gained attention and credibility, as demonstrated by the vast number of certified projects around the world and the widely-known usefulness and advantages of their application. The Wa-Pa-Su project sustainability rating system presents an integrated approach to sustainability assessment by integrating three distinctive areas of knowledge: (1) sustainable development theory and fundamentals supports the ultimate goal of the rating system, which is to contribute to sustainability, with the aim of finding a path to balance social, economic, and environmental needs; (2) continual performance improvement becomes essential due to the duration of the projects, as it is critical to allow organizations or projects to improve performance over time; and (3) multi-criteria decision analysis assists with the assessment process through stakeholder engagement and participation, and the design and implementation of a criteria weighting system. 相似文献
736.
Marius Warg Næss 《国际发展与全球生态学杂志》2013,20(2):123-133
Mobility has been argued to be the single factor explaining why some pastoralists do relatively well during extreme climatic events, while others do not, because mobility works by taking advantage of the spatial and temporal structure of resource failure by moving away from scarcity towards abundance. In spite of this, a common governmental management strategy is to resettle pastoral populations and thereby significantly reduce mobility. By revealing the underlying logic of mobility for Tibetan pastoralists, this paper questions official policy that aims at privatizing communally owned rangelands since it reduces pastoral flexibility and access to key resources. This is especially pertinent in the face of climate change. While little is known as to the specifics of how climate change will affect nomadic pastoralists, environmental variability is likely to increase. Consequently, policies resulting in decreased mobility may exacerbate the negative effects of climate change because of a positive feedback between climate and negative density dependence. 相似文献
737.
SUMMARY This paper is concerned with a twenty-five year campaign against the relocation of the Komatsu-Tenmangu shrine as a result of the enlargement of the Kakehashi river. The Komatsu-Tenmangu shrine is an important cultural property of Japan, and was constructed by Toshitsune Maeda, the third dynasty of the Kaga clan in 1657. It is suggested that the primary reason why it took so long to settle this issue is a flaw in our social system for managing public works. It is concluded that preservation of cultural property is not always contrary to land development, and that the proposed procedures or something like them must be put into practice for the real expansion of our culture. 相似文献
738.
Marine organisms are continuously exposed to agents, both exogenous and endogenous, that damage DNA. Consequently, it is important to determine the ability of compounds to provide protection against damaging chemicals. The aim of this study was to evaluate the anti-genotoxic activity of crude aqueous extracts of Kappaphycus alvarezii (Rhodophyceae), collected from the Southeast coast of India. This study focused on possible anti-genotoxic potential of aqueous extract of K. alverazii to interfere with clastogenicity induced by mercury chloride (HgCl2) in marine fish, Therapon jarbua as measured by cytogenetic endpoints such as cell viability and comet assay. In the first set of experiments, fish were exposed to a single treatment of Hg at 0.125, 0.25, 0.5, 1, or 2?ppm along with controls. Mercury exposure produced significant DNA damage in all comet classes, maximum as >79% (Class 4) at 0.5, 1, and 2?ppm exposure in a time dependent manner. Algal extract did not induce genotoxicity when given alone and prevented Hg-induced genotoxicity. The algal extract reduction in genotoxicity was significant but not time- and concentration-dependent. Results suggested that under present experimental conditions, K. alvarezii extract exhibit potent anti-genotoxicity effects in this fish model; and thus these extracts may be recommended as a supplement in fish meal and may benefit humans ingesting Hg-contaminated fish. 相似文献
739.
A spore germination-based concept and its transformation into a field level prototype for monitoring aflatoxin M1 (AFM1) in milk was developed. Initially, 15 strains of Bacillus spp. procured from different culture collection were screened for AFM1 sensitivity using spot assay and marker strain showing inhibition at 0.5 ppb was selected based upon maximum zone of inhibition. The selected strain B. megaterium 2949 was further screened for different enzymes activities and subsequently its spores were produced to an extent of 73.13% ± 3.197% in newly developed sporulation medium containing beef extract (0.0075% ± 0.0004%), yeast extract (0.015% ± 0.001%), peptone (0.0375% ± 0.0016%), and sodium chloride (0.0375% ± 0.0018%). A spore germination-based concept/ assay was optimized by immobilizing spores in eppendorf with pretreated milk (80°C/15 min) containing germinant and chromogenic substrate followed by incubation at 37°C. The appearance of sky blue color within real time of 45 min indicated spores germination and release of specific marker enzyme such as acetyl esterase and its specific action on chromogenic substrate which demonstrates absence of AFM1 in milk. However, if there was no color change, presence of AFM1 at 0.5 ppb MRL was denoted by Codex. The developed concept on AFM1 detection was validated and a correlation of 0.97 was established with AOAC approved Charm 6602 and ELISA at Codex MRL with minimal false positive and negative results. The cost effective test has potential application in dairy farms, manufacturing, and R&D units for routine monitoring of AFM1 in milk. 相似文献
740.
Monitoring and modeling of the concentrations of trihalomethanes (THMs) within four water treatment plants (WTPs) and distribution lines in Fayoum City, Egypt, were studied. Sampling sites for raw and treated waters were determined by global positioning system and the Arc geographic information system software was used for mapping. THMs were monitored using 25 sampling points located at the plant exit and through the distribution lines up to the plant extremity. Results indicated that the THMs concentration varied significantly but it was very rarely higher than the allowed maximum contaminant level of 100 μg L?1. However, at the dead zones in the distribution lines, the THMs increased by about 160% compared to in-plant level. Furthermore, the level of THMs in hot months was about 1.3 times higher than in cold ones. The influence of some independent variables such as temperature, pH, ammonia concentration, total organic carbon and color were investigated by Pearson model to find their correlation with the rate of THMs formation in WTPs. The resulted R values ranged from 0.81 to 0.98. Successful application of the model to a selected region on the distribution lines has resulted in a correlation coefficient of 0.98. 相似文献