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41.
Aim of the present study is to determine the in-vitro cell cytotoxic effect of native and transformed cancer drugs (cyclophosphamide and etoposide) using three different white rot fungi (Ganoderma lucidum, Phanerochaete chrysosporium and Trametes versicolor). At 3, 6, 9, 12 and 15 days, experiments were done on a mouse monocyte macrophage cell line (Raw 264.7). After biodegradation, the altered compounds were found to be harmful to the Raw 264.7 cells. The maximal cytotoxicity of cyclophosphamide transformed products (TPs) were determined to be 2.4%, 7.3% and 7% respectively, against G. lucidum, P. chrysosporium and T. versicolor, respectively. With G. lucidum, P. chrysosporium and T. versicolor, the etoposide toxicity was 1.5%, 8% and 2.7% respectively. P. chrysosporium-mediated biodegradation resulted in the maximum toxicity, at 8%, on the 12th day for etoposide and 7.3% on the 3rd day for cyclophosphamide. After biodegradation by fungi, the toxicity of these two anticancer agents was reduced in the form of metabolites, but each fungus showed unique capacity for toxicity removal. 相似文献
42.
Augustine Donkor Paul Osei-Fosu Brajesh Dubey Robert Kingsford-Adaboh Cephas Ziwu Isaac Asante 《Environmental science and pollution research international》2016,23(19):18966-18987
Pesticides are known to improve agriculture yield considerably leading to an increase in its application over the years. The use of pesticides has shown varying detrimental effects in humans as well as the environment. Presently, enough evidence is available to suggest their misuse and overuse in the last few decades in most developing nations primarily due to lack of education, endangering the lives of farmers as well as the entire population and environment. However, there is paucity of data especially over long durations in Ghana resulting in the absence of effective monitoring programs regarding pesticide application and subsequent contamination in fruits and vegetables. Therefore, this review discusses comprehensively pesticide type and use, importation, presence in fruits and vegetables, human exposure, and poisoning in Ghana. This is to alert the scientific community in Ghana of the need to further research into the potential implications of pesticide residues in food commodities in order to generate a comprehensive and reliable database which is key in drafting policies simultaneous with food regulation, suitable monitoring initiatives, assessment, and education to minimize their effects thereon. 相似文献
43.
Haight RG Homans FR Horie T Mehta SV Smith DJ Venette RC 《Environmental management》2011,47(3):506-517
Economic assessment of damage caused by invasive alien species provides useful information to consider when determining whether
management programs should be established, modified, or discontinued. We estimate the baseline economic damage from an invasive
alien pathogen, Ceratocystis fagacearum, a fungus that causes oak wilt, which is a significant disease of oaks (Quercus spp.) in the central United States. We focus on Anoka County, Minnesota, a 1,156 km2 mostly urban county in the Minneapolis-Saint Paul metropolitan region. We develop a landscape-level model of oak wilt spread
that accounts for underground and overland pathogen transmission. We predict the economic damage of tree mortality from oak
wilt spread in the absence of management during the period 2007–2016. Our metric of economic damage is removal cost, which
is one component of the total economic loss from tree mortality. We estimate that Anoka County has 5.92 million oak trees
and 885 active oak wilt pockets covering 5.47 km2 in 2007. The likelihood that landowners remove infected oaks varies by land use and ranges from 86% on developed land to
57% on forest land. Over the next decade, depending on the rates of oak wilt pocket establishment and expansion, 76–266 thousand
trees will be infected with discounted removal cost of $18–60 million. Although our predictions of removal costs are substantial,
they are lower bounds on the total economic loss from tree mortality because we do not estimate economic losses from reduced
services and increased hazards. Our predictions suggest that there are significant economic benefits, in terms of damage reduction,
from preventing new pocket establishment or slowing the radial growth of existing pockets. 相似文献
44.
The global agenda of sustainable development (SD) will get a major boost from the successful implementation of the Sustainable Development Goals (SDGs) in developing countries. This requires effective planning and understanding of the SDGs at the national level and developing sound SDG indicators that account for country priorities. Currently, there is no formal SDG indicator set in India, but the process for it is underway. This paper has attempted to propose a unique technique for identifying the most representative indicator set for SD measurement in India based on the SDGs. Considering the needs and preferences of the country, a three‐stage process is proposed to develop the priority indicator set. The application of the approach has been presented for SDG 7, which relates to energy. This is supported with a background on India's SD progress. The proposed technique is simple yet effective, and can be easily replicated by other developing countries. 相似文献
45.
Yongxin Zhang Seth C. Olsen Manvendra K. Dubey 《Atmospheric environment (Oxford, England : 1994)》2010,44(24):2799-2812
This paper examines the impact of tripled anthropogenic emissions from China and India over the base level (gaseous species and carbonaceous aerosols for 2000) on air quality over the U.S. using the WRF/Chem (Weather Research and Forecasting – Chemistry) model at 1° resolution. WRF/Chem is a state-of-the-science, fully coupled chemistry and meteorology system suitable for simulating the transport and dispersion of pollutants and their impacts. The analyses in this work were focused on MAM (March, April and May). The simulations indicate an extensive area of elevated pollutant concentrations spanning from the Arabian Sea to the Northern Pacific and to the Northern Atlantic. MAM mean contributions from the tripled Asian emissions over the U.S. are found to be: 6–12 ppbv for CO, 1.0–2.5 ppbv for O3, and 0.6–1.6 μg m?3 for PM2.5 on a daily basis. 相似文献
46.
Comparisons of WRF/Chem simulated O3 concentrations in Mexico City with ground-based RAMA measurements during the MILAGRO period 总被引:1,自引:0,他引:1
Yongxin Zhang Manvendra K. Dubey 《Atmospheric environment (Oxford, England : 1994)》2009,43(30):4622-4631
This work compares the WRF/Chem (Weather Research and Forecasting – Chemistry) simulated O3 concentrations in the Mexico City Metropolitan Area (MCMA) with measurements from the ground-based RAMA network during the MILAGRO (Megacity Initiative: Local and Global Research Observations) period. The model resolves the observations reasonably well in terms of diurnal cycle and mean magnitude as reflected by high correlation coefficients and low root-mean-square errors. Stations located in the center of the MCMA generally exhibit higher correlation coefficients and lower model biases than those stations located in the peripheral of the MCMA. Large temporal variations in the observed and simulated O3 concentrations are noted from station to station during the MILAGRO period. Sensitivity analyses of O3 concentrations to changes in NOx and VOC emissions rates suggest that O3 production in the MCMA is VOC-sensitive, and VOC-emissions reduction appears to be an effective strategy for reducing high surface O3 concentrations in the MCMA. 相似文献
47.
Townsend T Dubey B Tolaymat T Solo-Gabriele H 《Journal of environmental management》2005,75(2):105-113
Disposal of discarded chromated copper arsenate (CCA)-treated wood in landfills raises concerns with respect to leaching of preservative compounds. When unweathered CCA-treated wood is leached using the toxicity characteristic leaching procedure (TCLP), arsenic concentrations exceed the toxicity characteristic (TC) limit of 5mg/L in most cases. The majority of discarded CCA-treated wood, however, results from demolition activities, where the wood has typically been subjected to weathering. Since preservatives do migrate from the wood during its normal use, leaching characteristics of weathered and aged CCA-treated wood may differ from unweathered wood. To evaluate this, CCA-treated wood removed from service after various degrees of weathering was collected from multiple sources and leached with the TCLP, the synthetic precipitation leaching procedure (SPLP) and California's waste extraction test (WET). Five to seven individual pieces of wood were analyzed from each source. The average TCLP arsenic concentration for the 14 sources ranged from 3.2 to 13 mg/L. The average TCLP concentrations of the 100 wood pieces tested were 6.4, 5.9 and 3.2 mg/L for arsenic, copper and chromium, respectively. Overall, in 60 out of 100 samples tested by the TCLP, arsenic concentrations exceeded 5 mg/L (the TC regulatory value). SPLP leachate concentrations were similar to TCLP concentrations, although copper leached somewhat more with the TCLP. WET leachate concentrations were approximately a factor of 10 higher than TCLP concentrations. Discarded CCA-treated wood, even after exposure to years of weathering, often exceeds the TC limit for arsenic and without the current regulatory exemption would possibly require management as a TC hazardous waste in the US. 相似文献
48.
Chandra A Dubey A 《Journal of environmental biology / Academy of Environmental Biology, India》2010,31(4):403-407
Cenchrus is an important component of major grass cover of world. Similar to the other major tropical grasses most of the species in genus Cenchrus are also apomictic in nature hence correct and precise identification of accessions and species are problematic and dubious. In the present study 187 decamer oligonucleotide primers were tested for PCR-based DNA amplification of six prominent species of genus Cenchrus. Of these, 32 potential repetitive and polymorphic primers were tested for identification of species-specific markers for C. ciliaris, C. setigerus, C. pennisetiformis, C. prieurri, C. biflorus and C. myosuroides. These primers yielded 51 unique RAPD markers either specific to a species (37) or shared by two or more species (14). Maximum markers were shared between C. ciliaris and C. setigerus confirming theirmore closeness to each other Primers like OPF09, OPF11, OPR15, OPAJ11, OPQ10 and OPAK20 generated strong intense bands can be used on priority in identifying the species from their natural habitat for the development of species-specific core germplasm. Due to apomictic nature this is the prime method of developing cultivars, as morphological characters are largely unable to distinguish them. The level of variation observed clearly suggest RAPD as an appropriate marker for genetic studies and in identifying the lines with species-specific markers for Cenchrus germplasm management activity and also maintaining identity and purity for proprietary reasons. 相似文献
49.