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31.
Majority of the people of Pakistan get drinking water from groundwater source. Nearly 40 % of the total ailments reported in Pakistan are the result of dirty drinking water. Every summer, thousands of patients suffer from acute gastroenteritis in the Rawal Town. Therefore, a study was designed to generate a water quality index map of the Rawal Town and identify the relationship between bacteriological water quality and socio-economic indicators with gastroenteritis in the study area. Water quality and gastroenteritis patient data were collected by surveying the 262 tubewells and the major hospitals in the Rawal Town. The collected spatial data was analyzed by using ArcGIS spatial analyst (Moran’s I spatial autocorrelation) and geostatistical analysis tools (inverse distance weighted, radial basis function, kriging, and cokriging). The water quality index (WQI) for the study area was computed using pH, turbidity, total dissolved solids, calcium, hardness, alkalinity, and chloride values of the 262 tubewells. The results of Moran’s I spatial autocorrelation showed that the groundwater physicochemical parameters were clustered. Among IDW, radial basis function, and kriging and cokriging interpolation techniques, cokriging showed the lowest root mean square error. Cokriging was used to make the spatial distribution maps of water quality parameters. The WQI results showed that more than half of the tubewells in the Rawal Town were providing “poor” to “unfit” drinking water. The Pearson’s coefficient of correlation for gastroenteritis with fecal coliform was found significant (P?P?P?相似文献   
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Environmental Monitoring and Assessment - Few estuaries remain unaffected by water management and altered freshwater deliveries. The Caloosahatchee River Estuary is a perfect case study for...  相似文献   
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In the current study, the chemistry of fresh and stored rainwater of Thar Desert, Pakistan, was estimated during two consecutive monsoon periods. The present research deals with the variation in physicochemical parameters, total arsenic (Ast), inorganic arsenic species (Asi, AsV, AsIII), and fluoride (F?) in stored rainwater (SRW) at different time intervals (1 week to 3 months). The pH of fresh rainwater (FRW) samples showed slightly acidic to neutral in nature (6.08–7.06) which were inconsistent with the reference pH value (5.6) of rainwater. The resulted data indicated that Ast and F? levels in SRW were enhanced with time duration. The levels of Ast and F? in SRW after different time intervals were found in the range of 194–683 μg/L and 10–35.4 mg/L, respectively. The values of Ast and F? were 20–70 and 7–24 times higher than those of WHO permissible limits, 10 μg/L and 1.5 mg/L, respectively. The AsIII was dominant species in SRW, which corresponds to >60 % of Asi. The characteristics of the SRW revealed an unacceptable quality to consume for drinking and agricultural purposes in the studied area.  相似文献   
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This study was conducted to assess efficacy of biological control against bacterial leaf blight (BLB) of rice produced by Xanthomonas oryzae pv. oryzae. Five endophytic strains (A1, A2, A3, A13 and A15) and two rhizospherial Bacilli (D29 and H8) were tested for their antagonistic activities against BLB in vitro and in vivo. All seven strains showed high potential of antagonistic activity against X. oryzae pv. oryzae and three phytopathogenic fungi in vitro. Test of 16SrRNA gene sequence were assigned isolates A1, A3 and A13 as Bacillus amyloliquefaciens while isolates A2 and A15 as B. methylotrophicus and B. subtilis, respectively. In greenhouse, four strains of displayed 50.29%–57.86% inhibition rate against the pathogen and significantly increased plant fresh weight from 50.03% to 73.11% and dry weight from 64.11% to 86.65% in treated rice plants. In addition, these strains demonstrated strong capability to produce indole-3-acetic acid, siderophores, solubilizing phosphate and also colonize roots. Real-time quantitative polymerase chain reaction revealed that expression of defense-related genes including OsAOS2, OsJMT1, OsNPR1 and OsPR1b were significantly up-regulated in leaves of D29-exposed rice plants, suggesting that treatment of rice with D29 suppressed BLB through systemic activation of the plant defense system. Therefore, data suggest that Bacillus isolates A13, A15, D29 and H8 support effective antagonistic activity against BLB under greenhouse conditions in addition to their potential to promote growth of rice plants.  相似文献   
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Evaluation of biological effects using a rapid, sensitive and cost effective method can indicate specific information on toxicity/ecotoxicity. Since assays based on animals, plants and algae are expensive, time consuming and require large sample volume, recent studies have emphasized the benefits of rapid, reproducible and cost effective bacterial assays for toxicity screening and assessment. This review focuses on a bacterial assay, i.e., Vibrio fischeri bioluminescence inhibition assay, which is often chosen as the first test in a test battery based on speed and cost consideration. The test protocol is simple and was originally applied for aqueous phase samples or extracts. The versatility of the assay has increased with subsequent modification, i.e., the kinetic assay for turbid and colored samples and the solid phase test for analyzing sediment toxicity. Researchers have reported the Vibrio fischeri bioluminescence assay as the most sensitive across a wide range of chemicals compared to other bacterial assays such as nitrification inhibition, respirometry, ATP luminescence and enzyme inhibition. This assay shows good correlations with other standard acute toxicity assays and is reported to detect toxicity across a wide spectrum of toxicants.  相似文献   
37.

Over the last few decades, the atmospheric carbon dioxide emission has been amplified to a great extent in Pakistan. This amplification may cause global warming, climate change, and environmental degradation in Pakistan. Consequently, ecological condition and human life may suffer in the near future from these indicated threats. Therefore, an attempt was made to test the relationship between globalization and carbon dioxide emissions in case of Pakistan. The study covers the time series data over the period of 1975–2014. We employed modern econometric techniques such as Johansen co-integration, ARDL bound testing approach, and variance decomposition analysis. Results of the Johansen co-integration test show that there is a significant long-run relationship between carbon dioxide emissions and globalization. The long-run elasticities of the ARDL model show that a 1% increase in economic globalization, political globalization, and social globalization will increase carbon dioxide emissions by 0.38, 0.19, and 0.11%, respectively. Further, our findings reveal that the environmental Kuznets curve (EKC) hypothesis prevails an inverted U-shaped relationship between carbon dioxide emission and economic growth. Therefore, the EKC hypothesis is valid in the presence of globalization. The diagnostic test results show that the parameters of the ARDL model are credible, stable, and reliable in the current form. Finally, variance decomposition analysis displays that economic, political, and social globalization are contributing significantly to carbon dioxide emissions in Pakistan.

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This study aimed to assess the impacts of climate change on residential energy consumption in Dhaka city of Bangladesh. The monthly electricity consumption data for the period 2011–2014 and long-term climate variables namely monthly rainfall and temperature records (1961–2010) were used in the study. An ensemble of six global circulation models (GCMs) of coupled model intercomparison project phase 5 (CMIP5) namely, BCCCSM1-1, CanESM2, MIROC5, MIROC-ESM, MIROC-ESM-CHEM, and NorESM1-M under four representative concentration pathway (RCP) scenarios were used to project future changes in rainfall and temperature. The regression models describing the relationship between historical energy consumption and climate variables were developed to project future changes in energy consumptions. The results revealed that daily energy consumption in Dhaka city increases in the range of 6.46–11.97 and 2.37–6.25 MkWh at 95% level of confidence for every increase of temperature by 1 °C and daily average rainfall by 1 mm, respectively. This study concluded that daily total residential energy demand and peak demand in Dhaka city can increase up to 5.9–15.6 and 5.1–16.7%, respectively, by the end of this century under different climate change scenarios.  相似文献   
40.
Bisphenol S has been introduced into some industrial applications and it may act as a xeno-estrogen that can alter endocrine functions and reproduction. The present study was carried out to examine the effect of bisphenol S exposure on oxidative stress, generation of reactive oxygen species, and DNA integrity in rat spermatozoa in vitro and daily sperm production and sperm DNA damage in vivo. Sperm were incubated with bisphenol S at concentrations of 0.5, 1, 10, and 100 µg/L. At the highest concentration, bisphenol S induced formation of reactive oxygen species, caused lipid peroxidation, affected superoxide dismutase levels, and increased DNA fragmentation. Adult rats were exposed to doses of 0.5, 5, 25, and 50 µg/kg/d for 28 days. Decrease in daily sperm production and an increase in sperm DNA damage was observed at the highest dose in the 50 µg/kg/d treated group, but sperm motility was not reduced.  相似文献   
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