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141.
Mohammad Aslam Khan S. Akhtar Ali Shah 《Journal of Agricultural and Environmental Ethics》2011,24(5):493-509
There is evidence of continued food insecurity and malnutrition in Pakistan despite significant progress made in terms of
food production in recent years. According to “Vision 2030” of the Planning Commission of Pakistan, about half of the population
in the country suffers from absolute to moderate malnutrition, with the most vulnerable being children, women, and elderly
among the lowest income group. The Government of Pakistan has been taking a series of policy initiatives and strategic measures
to combat food insecurity issues. These range from increasing production to food imports, implementation of poverty reduction
strategies, nutritional improvement programs, as well as provision of social safety nets. The article aims to instill some
fresh thinking into the debate regarding the challenges of food security. It underscores the limitations of hitherto policy
response, and suggests crucial measures to improve the present grim scenario. Policy makers, planners, practitioners, and
academicians in countries with comparable socio-political and economic setup can view this discussion as a case study and
may apply the findings in their domain accordingly. 相似文献
142.
Mohammad Zubair Alam Shamim Ahmad Abdul Malik 《Environmental monitoring and assessment》2011,178(1-4):281-291
In the present study, a total of 198 bacteria were isolated, 88 from the tannery effluents and 110 from agricultural soil irrigated with the tannery effluents. Tannery effluents and soils were analyzed for metal concentrations by atomic absorption spectrophotometer. The tannery effluents and soil samples were found to be contaminated with chromium, nickel, zinc, copper, and cadmium. All isolates were tested for their resistance against Cr6?+?, Cr3?+?, Ni2?+?, Zn2?+?, Cu2?+?, Cd2?+?, and Hg2?+?. From the total of 198 isolates, maximum bacterial isolates were found to be resistant to Cr6?+? 178 (89.9%) followed by Cr3?+? 146 (73.7%), Cd2?+? 86 (43.4%), Zn2?+? 83 (41.9%), Ni2?+? 61 (30.8%), and Cu2?+? 51 (25.6%). However, most of the isolates were sensitive to Hg2?+?. Among the isolates from tannery effluents, 97.8% were resistant to Cr6?+? and 64.8% were resistant to Cr3?+?. Most of the soil isolates were resistant against Cr6?+? (83.6%) and Cr3?+? (81.8%). All isolates were categorized into Gram-positive and Gram-negative bacteria. In a total of 114 Gram-positive isolates, 91.2% were resistant to Cr6?+? followed by 73.7% to Cr3?+?, 42.1% to Zn2?+?, 40.4% to Cd2?+?, and 32.5% to Ni2?+?. Among Gram-negative isolates, 88.1% were found showing resistance to Cr6?+?, 75.0% to Cr3?+?, and 47.6% were resistant to Cd2?+?. Majority of these metal-resistant isolates were surprisingly found sensitive to the ten commonly used antibiotics. Out of 198 isolates, 114 were found sensitive to all antibiotics whereas only two isolates were resistant to maximum eight antibiotics at a time. Forty-one and 40 isolates which constitute 20.7% and 20.2% were resistant to methicilin and amoxicillin, respectively. 相似文献
143.
Azizian MF Nelson PO Thayumanavan P Williamson KJ 《Waste management (New York, N.Y.)》2003,23(8):719-728
The practice of incorporating certain waste products into highway construction and repair materials (CRMs) has become more popular. These practices have prompted the National Academy of Science, National Cooperative Highway Research Program (NCHRP) to research the possible impacts of these CRMs on the quality of surface and ground waters. State department of transportations (DOTs) are currently experimenting with use of ground tire rubber ( crumb rubber) in bituminous construction and as a crack sealer. Crumb rubber asphalt concrete (CR-AC) leachates contain a mixture of organic and metallic contaminants. Benzothiazole and 2(3H)-benzothiazolone (organic compounds used in tire rubber manufacturing) and the metals mercury and aluminum were leached in potentially harmful concentrations (exceeding toxic concentrations for aquatic toxicity tests). CR-AC leachate exhibited moderate to high toxicity for algae ( Selenastrum capriconutum) and moderate toxicity for water fleas ( Daphnia magna). Benzothiazole was readily removed from CR-AC leachate by the environmental processes of soil sorption, volatilization, and biodegradation. Metals, which do not volatilize or photochemically or biologically degrade, were removed from the leachate by soil sorption. Contaminants from CR-AC leachates are thus degraded or retarded in their transport through nearby soils and ground waters. 相似文献
144.
Ahmed Mukhtar Abdullah Anas Patle Dipesh S. Shahadat Mohammad Ahmad Zainal Athar Moina Aslam Mohammad Vo Dai-Viet N. 《Environmental Chemistry Letters》2022,20(1):335-378
Environmental Chemistry Letters - Biodiesel is a sustainable alternative to petroleum diesel. The main bottlenecks in the commercialization of biodiesel are production costs and suitable industrial... 相似文献
145.
Esfanjani Pouya Jahangiri Sajjad Heidarian Ali Valipour Mohammad Sadegh Rashidi Saman 《Environmental science and pollution research international》2022,29(28):42616-42646
Environmental Science and Pollution Research - Solar energy is the most sustainable and free source to manage the world energy demand. One aspect of solar-driven energy supply can be observed in... 相似文献
146.
Zahed Mohammad Ali Salehi Samira Tabari Yasaman Farraji Hossein Ataei-Kachooei Saba Zinatizadeh Ali Akbar Kamali Nima Mahjouri Mohammad 《Environmental science and pollution research international》2022,29(39):58561-58589
Environmental Science and Pollution Research - Phosphorus is one of the main nutrients required for all life. Phosphorus as phosphate form plays an important role in different cellular processes.... 相似文献
147.
Siddique YH Ara G Beg T Afzal M 《Journal of environmental biology / Academy of Environmental Biology, India》2007,28(2):279-282
Antioxidants and plant products are reported to reduce the genotoxic damage of steroids. In our present study we have tested different dosages of nordihydroguaiaretic acid (NDGA) against the genotoxic damage induced by ethynodiol diacetate in the presence of S9 mix. Treatments with nordihydroguaiaretic acid (NDGA) results in the reduction of the genotoxic damage. A significant decrease was observed at all the tested doses of NDGA in sister chromatic exchanges of number of abnormal cells. The results suggest a protective role of NDGA against the genotoxic damage. 相似文献
148.
Mudassar Khan Ashiq Mohammad Karam Ahad Athanasios Katsoyiannis Salman Akbar Malik Muhammad Abdullaha Azhar Rashid Mauro Fasola Alamdar Hussain Habib Bokhari Syed Ali Musstjab Akber Shah Eqani 《Environmental geochemistry and health》2014,36(3):375-384
We investigated selected chlorinated pollutants (β-HCH, γ-HCH, DDDs, DDEs, o,p′-DDT, p,p′-DDT, heptachlor, aldrin, dieldrin, and endrin) in the Lahore and the Sialkot districts of Pakistan, using eggs of cattle egret (Bubulcus ibis) collected during May and June 2007. The pollutant with highest level and frequency was ΣDDT, followed by β-HCH, γ-HCH, heptachlor, aldrin, dieldrin, and endrin in descending order. The concentration(s) were significantly higher in Sialkot heronry for all the pollutants (except p,p′-DDT) than in Lahore. The values for DDTs, β-HCH, γ-HCH, and heptachlor were significantly higher (p < 0.05) in the egg(s) than in sediment(s) and in the chicks’ diet, due to biomagnification. Among DDTs analogues, p,p′-DDD was the major contaminant with >60 % of total DDT burden, reflecting the widespread aged as well as recent use of DDT as well as anaerobic degradation (DDD/DDE > 1 in many cases) in the nearby paddy soils. In few samples, p,p′-DDT/(DDD + DDE) > 0.5 suggested the recent emission patterns from surrounding contaminated areas of demolished DDT units and obsolete pesticide stores. The higher levels of HCHs (i.e., β-HCH) in the samples collected from Sialkot indicate exposure from long-term agricultural use. Overall, concentrations of all studied POPs were less than the threshold levels known to affect reproduction. Nevertheless, total DDTs and/or HCHs burdens in some eggs contained concentrations of greater than what would educe adverse effects on birds. This is among few studies on OCPs exposure to avian species, which provide the evidence of Pakistan’s contribution toward the Global POPs emission. 相似文献
149.
Mohammad Mohammadi Mohammad Salehi J. N. K. Rao 《Environmental and Ecological Statistics》2014,21(2):351-371
Perez and Pontius (J Stat Comput Simul 76:755–764, 2006) introduced several bootstrap methods under adaptive cluster sampling using a Horvitz–Thompson type estimator. Using a simulation study, they showed that their proposed methods provide confidence intervals with highly understated coverage rates. In this article, we first show that their bootstrap methods provide biased bootstrap estimates. We then define two bootstrap methods, based on the method of Gross (Proceeding of the survey research methods section. American Statistical Association, Alexandria, VA, pp 181–184, 1980) and Bootstrap With Replacement, that provide unbiased bootstrap estimates of the population mean with bootstrap variances matching the corresponding unbiased variance estimator. Using a simulation study, we show that the bootstrap confidence intervals based on our proposed methods have better performance than those based on available bootstrap methods, in the sense of having coverage proportion closer to the nominal coverage level. We also compare the proposed intervals to empirical likelihood based intervals in small samples. 相似文献
150.
The Gulf of Aqaba exhibits a strong seasonality due to convective mixing during winter and stratification during summer. The present study provides a detailed appraisal of summer and winter sea-water characteristics at the northern coast of the Gulf of Aqaba, that is witnessing rapid development and increasing changes in its geomorphological characteristics. Sea-water temperature, salinity, nutrients, and chlorophyll a concentrations were measured biweekly at five coastal and four cross-sectional stations during the periods February to April and July to September 2004. Meteorological conditions were continuously recorded at the Marine Science Station. The coastal study sites included four open coastal stations and a marina with one-way exchange with the open water. The effect of convective mixing was clearly apparent on the sea-water characteristics. Natural seasonal characteristics of higher nutrients and chlorophyll a concentrations were recorded during winter at most of the open coastal stations. In the cross-sectional stations, the concentrations of nutrients and chlorophyll a were not different between the surface and the bottom during winter, but the bottom waters had generally higher concentrations during summer. Some deviations from the natural seasonal cycle were recorded at the marina and other coastal stations. Here, higher nutrient and chlorophyll a concentrations were recorded in summer than in winter. These deviations that are most likely due to anthropogenic effects are discussed. 相似文献