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31.
Tripathi  Rahul  Dhal  B.  Shahid  Md  Barik  S. K.  Nayak  A. D.  Mondal  B.  Mohapatra  S. D.  Chatterjee  D.  Lal  B.  Gautam  Priyanka  Jambhulkar  N. N.  Fitton  Nuala  Smith  Pete  Dawson  T. P.  Shukla  A. K.  Nayak  A. K. 《Environment, Development and Sustainability》2021,23(8):11563-11582

A study was conducted to examine the interrelationships among socioeconomic factors, household consumption patterns, calorie intake and greenhouse gas emissions factors in rural eastern India based on household survey data. Findings indicated that higher monthly per capita incomes (12.1–80.1$) were associated with greater average calorie intakes (2021–2525 kcal d?1). As estimated by the FEEDME model, in total 17.2% of the population was calorie malnourished with a regional disparity of 29.4–18.2% malnourishment. Greenhouse gas (GHG) emissions were calculated only on the basis of crop and livestock production and consumption. Rice accounted for the highest share of total GHG emissions, on average 82.6% on a production basis, which varied from 58.1% to 94.9% in regional basis. Rice contributed the greatest share (~?65% and 66.2%) in terms of both calories and GHG emissions (CO2 eq y?1), respectively, on a consumption basis. We conclude that extensive rice farming and increasing animal product consumption are dominant factors in the higher carbon footprint in this region and are likely to further increase with increase in per capita income. This study provides useful information to help for better crop planning and for fine-tuning food access policy, to reduce carbon footprint and calorie malnutrition.

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In this study we have examined the effect of exposure to different congeners of PCBs and their role in oxidative stress response. A metabolically competent human liver cell line (HepG2) was exposed with two prototype congeners of PCBs: coplanar PCB-77 and non-coplanar PCB-153. After the predetermined times of exposure (0–24 h) at 70 μM concentration, the HepG2 cells showed significant apoptotic changes by fluorescent microscopy after 12 h of exposure. Gene set enrichment analysis (GSEA) identified oxidative stress as the predominant enrichment. Further, paraquat assay showed that PCB congeners lead to oxidative stress to different extents, PCB-77 being more toxic. This study, with emphasis on all recommended microarray quality control steps, showed that apoptosis was one of the most significant cellular processes as a result of oxidative stress, but each of these congeners had a unique signature gene expression, which was further validated by Taqman real time PCR and immunoblotting. The pathways involved leading to the common apoptotic effect were completely different. Further in-silico analysis showed that PCB-153 most likely acted through the TNF receptor, leading to oxidative stress involving metallothionein gene families, and causing apoptosis mainly by the Fas receptor signaling pathway. In contrast, PCB-77 acted through the aryl hydrocarbon receptor. It induced oxidative stress through the involvement of cytochrome P450 (CYP1A1) leading to apoptosis through AHR/ARNT pathway.  相似文献   
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East Calcutta Wetlands, a Ramsar site, receives a huge amount of the city’s composite industrial effluent (~600 million liters per day) throughout the year. The waste-element-contaminated water flows down through a major storm water flow (SWF) canal into the wetland for nearly 40 km farther eastward and is finally discharged into Kultigong river that flows through the eastern limit of the wetland and that in turn unites with river Ganga. Elemental load in water and bottom sediment at selected sites of the SWF canal was assessed by proton-induced X-ray emission and atomic absorption spectroscopy techniques. Gradual decrease in concentration levels of elements was observed in both water and bottom sediments of SWF canal up to its site of confluence at Kultigong, indicating natural remediation processes taking place along the canal up to the confluence at Ganga estuary. Any further conversion of this wetland area should be prevented to get the benefit from this no-cost natural cleanup process in connection to pollution prevention.  相似文献   
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This paper presents a comprehensive account regarding concentration, distribution and possible sources of trace elements (Al, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Zn) in 20-30 cm sediment cores (<63 microm particle size) collected at the confluence of the Ganges River and Bay of Bengal (Sunderban wetland, India). This work aims to evaluate the fluvio-marine and geochemical processes influencing the metal distribution. The most interesting features are the downward increase of concentrations of majority of the elements reaching overall maximum values at a depth of 10-15 cm observed in station Lot No.8 located along the main stream of the Ganges estuary as well as an overall elevated concentration of all the elements in the lower littoral zone. The interelemental relationship revealed the identical behaviour of elements during its transport in the estuarine environment. The overall variation in concentration can be attributed to differential discharge of effluents originating from industrial and agricultural as well as from domestic sewage. Arsenic exceeded effects range - low (ER - L) concentrations, implying occasional or frequent adverse biological effects. For Cu, Ni and Cr a smaller proportion of samples had exceeded the ER - L values indicating that the dataset would be suitable for future use in evaluating predictive abilities of SQGs.  相似文献   
35.
Mixing ratios of 15 carbonyls and BTEX (benzene, toluene, ethyl benzene, xylenes) were measured for the first time in ambient air of Kolkata, India at three sites from March to June 2006 and their photochemical reactivity was evaluated. Day and nighttime samples were collected on weekly basis. Formaldehyde was the most abundant carbonyl (mean concentration ranging between 14.07 microg m(-3) to 26.12 microg m(-3) over the three sites) followed by acetaldehyde (7.60-18.67 microg m(-3)) and acetone (4.43-10.34 microg m(-3)). Among the high molecular weight aldehydes, nonanal showed the highest concentration. Among the mono-aromatic VOCs, mean concentration of toluene (27.65-103.31 microg m(-3)) was maximum, closely followed by benzene (24.97-79.18 microg m(-3)). Mean formaldehyde to acetaldehyde (1.4) and acetaldehyde to propanal ratios (5.0) were typical of urban air. Based on their photochemical reactivity towards OH. radical, the concentrations of the VOCs were scaled to formaldehyde equivalent, which showed that the high molecular weight carbonyls and xylenes contribute significantly to the total OH-reactive mass of the VOCs. Due to the toxic effect of the VOCs studied, an assessment for both cancer risk and non-cancer hazard due to exposure to the population were calculated. Integrated life time cancer risk (ILTCR) due to four carcinogens (benzene, ethyl benzene, formaldehyde and acetaldehyde) and non-cancer hazard index for the VOCs at their prevailing level were estimated to be 1.42E-04 and 5.6 respectively.  相似文献   
36.
Chemical composition of rainwater changes from sea to inland under the influence of several major factors – topographic location of area, its distance from sea, annual rainfall. A model is developed here to quantify the variation in precipitation chemistry under the influence of inland distance and rainfall amount. Various sites in India categorized as ‘urban’, ‘suburban’ and ‘rural’ have been considered for model development. pH, HCO3, NO3 and Mg do not change much from coast to inland while, SO4 and Ca change is subjected to local emissions. Cl and Na originate solely from sea salinity and are the chemistry parameters in the model.Non-linear multiple regressions performed for the various categories revealed that both rainfall amount and precipitation chemistry obeyed a power law reduction with distance from sea. Cl and Na decrease rapidly for the first 100 km distance from sea, then decrease marginally for the next 100 km, and later stabilize. Regression parameters estimated for different cases were found to be consistent (R2 ~ 0.8). Variation in one of the parameters accounted for urbanization. Model was validated using data points from the southern peninsular region of the country. Estimates are found to be within 99.9% confidence interval.Finally, this relationship between the three parameters – rainfall amount, coastline distance, and concentration (in terms of Cl and Na) was validated with experiments conducted in a small experimental watershed in the south-west India. Chemistry estimated using the model was in good correlation with observed values with a relative error of ~5%. Monthly variation in the chemistry is predicted from a downscaling model and then compared with the observed data. Hence, the model developed for rain chemistry is useful in estimating the concentrations at different spatio-temporal scales and is especially applicable for south-west region of India.  相似文献   
37.
A Report on the Inter-regional Conference on Adaptation to Climate Change   总被引:1,自引:0,他引:1  
The IPCC Third Assessment highlighted theneed for adaptation to climate change.Keeping in view the importance ofadaptation to climate change, particularlyin developing countries, DevelopmentAlternatives organised an Inter-regionalConference on Adaptation to Climate Change,during October 18-20, 2002, just before CoP8 at New Delhi. About 120 participants frommore than 20 countries, both developed anddeveloping, participated in the conference.The conference discussed vulnerability ofnatural and human systems and communitypractices to adapt to climate change. Theconference deliberated on training andcapacity building of communities forincreasing their resilience to adapt toadverse impacts of climate change. Theparticipants also came out with a set ofrecommendations for wider dissemination tovarious stakeholders during the COP 8 beingheld at New Delhi (from 23 October to 1November). The recommendations from theconference were used in the COP 8negotiations as well as the DelhiMinisterial Declaration. The ConferenceReport will provide a guideline for thedeveloping countries for initiating work onadaptation.  相似文献   
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River Sabarmati is one of the biggest and major river of Gujarat that runs through two major cities of Gujarat, Gandhinagar and Ahmedabad and finally meets the Gulf of Khambhat (GoK) in the Arabian Sea. A study was conducted to evaluate the water quality of this river, as it could possibly be one of the major sources for filling up Kalpasar, the proposed man-made freshwater reservoir supposed to be the biggest one in the world. A total of nine sampling stations were established covering 163 km stretch of the river from upstream of Gandhinagar city to Vataman near Sabarmati estuary. Physicochemical (temprature, pH, salinity, chloride, total dissolved solids, turbidity, dissolved oxygen, biochemical oxygen demand, phenol, and petroleum hydrocarbons), biological (phytoplankton), and microbiological (total and selective bacterial count) analyses indicated that the river stretch from Ahmedabad-Vasana barriage to Vataman was highly polluted due to perennial waste discharges mainly from municipal drainage and industries. An implementation of sustainable management plan with proper treatment of both municipal and industrial effluents is essential to prevent further deterioration of the water quality of this river.  相似文献   
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