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Akhayere Evidence Essien Edidiong Augustine Kavaz Doga 《Environmental science and pollution research international》2019,26(25):25802-25813
Environmental Science and Pollution Research - In the present study, a comparative analysis was performed on the extraction of nickel ions (Ni2+) from agricultural wastewater using nanosilica (NS)... 相似文献
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Assessing hygiene and health related improvements of a rural water supply and sanitation programme in northern Ghana 总被引:1,自引:0,他引:1
A case control study was carried out to assess hygiene and health related improvements of the Rural Water Supply and Sanitation Programme in the Upper East Region of Ghana. Hygienic improvements were measured in terms of sources of water collection and storage arrangements, waste disposal, hand washing, food storage arrangements, and defecation and practices associated with faeces. The perception of women on the mode of transmission and treatment of selected water and sanitation related diseases were the criteria used to assess health related improvements. Comparison of the results in the programme and non-programme communities indicates that the water and sanitation programme has achieved some degree of success in the areas of water use and water and food storage for the beneficiaries. However, little has been accomplished in changing people's attitude towards the disposal of household, animal and human waste. In addition, the programme has so far been minimally effective in enhancing women's knowledge about the transmission and treatment of water and sanitation related diseases. 相似文献
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Mahesh Mohan Toms Augustine K. K. Jayasooryan M. S. Shylesh Chandran E. V. Ramasamy 《The Environmentalist》2012,32(4):383-393
Cochin estuary is one of the highly polluted aquatic systems of the southwest coast of India. The present study focuses on the assessment of heavy metals (Zn, Cd, Pb, and Cu) present in the sediments of Cochin estuary and the adjoining Periyar River. The sediments were analyzed for total metal content and various chemically bound fractions such as exchangeable, carbonate bound, easily reducible, organic, and residual. Total metal content of sediment was found higher than the average values reported from other Indian rivers. The mean concentration of Zn, Cd, Pb, and Cu in the sediments was 1,249.44, 9.5, 221.37, and 166.14???g/g, respectively. The results of sequential extraction showed that the concentration of Cd was high in the first two weakly bound fractions (exchangeable and carbonate bound) than the other metals, which are high in residual and organic bound fractions. Risk-assessment code analysis and environmental indices (enrichment factor and pollution load index) suggest that the sediments are highly polluted with metals, especially Cd. 相似文献
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Crentsil Kofi Bempah Augustine Kwame Donkor 《Environmental monitoring and assessment》2011,175(1-4):551-561
A number of pesticide residues in fruits were monitored at five markets in the Accra Metropolis for almost a year. Locally produced fruits (pawpaw and tomato) and imported apple were purchased from these selected markets in the metropolis and analyzed for pesticide residues by gas chromatography equipped with electron capture detector. In all, 320 sampled fruits were extracted and analyzed for pesticide residues, mainly organochlorines (??-HCH, ??-HCH, aldrin, heptachlor, ??-chlordane, heptachlor epoxide, ??-endosulfan, p,p??-DDE, endrin, ??-endosulfan, o,p??-DDT, endrin aldehyde, p,p??- DDT, endrin ketone, and methoxychlor). The data revealed that 32.8% of the fruit samples analyzed contained residues of the monitored insecticides above the accepted maximum residue limit (MRL) whereas 48.7% were below the MRL. Nonetheless, the continuous consumption of such fruits with modest pesticide levels can accumulate and could result in deadly chronic effects. 相似文献
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Global positioning system (GPS) collars have revolutionized the collection of animal location data; however, it is well-recognized that considerable bias can be present in these data due to habitat or behavior-induced obstruction of satellite signals resulting in inaccurate or missing locations. To date, no explicit theoretical framework of GPS fix acquisition specific to animal telemetry has been presented, and studies make differing assumptions regarding factors influencing GPS fix acquisition and how these data should be analyzed. Inappropriate statistical models have been used, interaction effects have been misunderstood, and the implementation of bias mitigation techniques has been problematic. Herein we outline current conceptual and analytical problems in the GPS animal telemetry literature, and subsequently present a theoretical model-based framework for GPS fix acquisition that clarifies the single and interactive effects of habitat and behavioral obstruction, fix interval, and collar model on GPS collar performance. By recognizing that GPS fix acquisition is a Bernoulli process, it becomes apparent that all forms of obstruction inherently interact with each other, making generalizations across study areas, study species, and collar models problematic. Stationary collar tests to determine the probability of fix acquisition (PFA), location accuracy, and the response to sources of obstruction are thus of limited applicability to animal-deployed collars. Bias mitigation techniques that extrapolate PFA models across samples, especially those using stationary collar tests to correct animal-deployed collars, are theoretically unsound. It is also demonstrated that nonlinearities in the relationships between sources of obstruction and PFA complicate PFA modeling with limited data and that even slight model misspecification can lead to considerable errors in correction factors, especially when using inverse weighting to mitigate bias. By emphasizing the importance of GPS collar sensitivity and ephemeris retention, the theoretical framework predicts that newer, more sensitive GPS collars will be less severely biased by sources of obstruction than reported for the older, less sensitive collars that have been used in the majority of GPS performance studies to date and we expect this trend to continue. This heuristic modeling exercise should be of value to researchers planning and analyzing studies using GPS collars and it also establishes a starting point for future theoretical investigations into GPS collar performance and bias mitigation. 相似文献
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Augustine O. Esogbue Zikehi M. Ahipo 《Journal of the American Water Resources Association》1982,18(3):451-456
Mathematical modeling of complex water resources System problems, particularly water pollution control, is aided by fizzy set theory. Public participation in large scale federally funded water resources and pollution control projects is now a federal requirement and practice of various planning agencies. However, no systems based model for quantifying and measuring the effectiveness of public participation is known to exist. In this paper, we report a fuzzy set based model developed for doing this in areawide water resources planning The model is essentially cascade in nature and employs the concepts of fuzzy pessimistic and optimistic aggregations to cluster and analyze the evaluations of the basic factors. Sample computations of the model are provided. 相似文献
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