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Comparative proteomic analysis in Miscanthus sinensis exposed to antimony stress Full text
2015
Xue, Liang | Ren, Huadong | Li, Sheng | Gao, Ming | Shi, Shengqing | Chang, Ermei | Wei, Yuan | Yao, Xiaohua | Jiang, Zeping | Liu, Jianfeng
To explore the molecular basis of Sb tolerance mechanism in plant, a comparative proteomic analysis of both roots and leaves in Miscanthus sinensis has been conducted in combination with physiological and biochemical analyses. M. sinensis seedlings were exposed to different doses of Sb, and both roots and leaves were collected after 3 days of treatment. Two-dimensional gel electrophoresis (2-DE) and image analyses found that 29 protein spots showed 1.5-fold change in abundance in leaves and 19 spots in roots, of which 31 were identified by MALDI-TOF-MS and MALDI-TOF-TOF-MS. Proteins involved in antioxidant defense and stress response generally increased their expression all over the Sb treatments. In addition, proteins relative to transcription, signal transduction, energy metabolism and cell division and cell structure showed a variable expression pattern over Sb concentrations. Overall these findings provide new insights into the probable survival mechanisms by which M. sinensis could be adapting to Sb phytotoxicity.
Show more [+] Less [-]Estimating future energy use and CO2 emissions of the world's cities Full text
2015
Singh, Shweta | Kennedy, Chris
This paper develops a tool for estimating energy-related CO2 emissions from the world's cities based on regression models. The models are developed considering climatic (heating-degree-days) and urban design (land area per person) independent variables. The tool is applied on 3646 urban areas for estimating impacts on urban emissions of a) global transitioning to Electric Vehicles, b) urban density change and c) IPCC climate change scenarios. Results show that urban density decline can lead to significant increase in energy emissions (upto 346% in electricity & 428% in transportation at 2% density decline by 2050). Among the IPCC climate scenarios tested, A1B is the most effective in reducing growth of emissions (upto 12% in electricity & 35% in heating). The tool can further be improved by including more data in the regression models along with inclusion of other relevant emissions and climatic variables.
Show more [+] Less [-]Organochlorine pesticides in follicular fluid of women undergoing assisted reproductive technologies from central China Full text
2015
Zhu, Yindi | Huang, Bo | Li, Qing X. | Wang, Jun
Female infertility rates have increased by approximately 4% since the 1980s. There is evidence of adverse effects on female fertility in relation to exposure of chemical pollution in recent years. Follicular fluid samples were collected from 127 woman patients (aged 20–35) who underwent assisted reproductive technologies (ART) and had no records indicating occupational exposure to OCPs. Seventeen OCPs were analyzed in this study. The results showed that methoxychlor was dominant, accounted for 13.4% of total OCPs with a mean concentration of 167.9 ± 33.9 ng/g lipid weight (lw), followed by heptachlor-epoxide, hexachlorocyclohexanes, endrin and DDT. The concentrations of OCPs in the follicular fluid samples in the present study were moderate in comparison with those reported from developed or industrialized countries. All these pollutants can accumulate in different tissues of human body through diet, drinking water and respiration. No correlation between patient age and OCP concentrations was observed in this study.
Show more [+] Less [-]Development and comparison of regression models for the uptake of metals into various field crops Full text
2015
Novotná, Markéta | Mikeš, Ondřej | Komprdová, Klára
Field crops represent one of the highest contributions to dietary metal exposure. The aim of this study was to develop specific regression models for the uptake of metals into various field crops and to compare the usability of other available models. We analysed samples of potato, hop, maize, barley, wheat, rape seed, and grass from 66 agricultural sites. The influence of measured soil concentrations and soil factors (pH, organic carbon, content of silt and clay) on the plant concentrations of Cd, Cr, Cu, Mo, Ni, Pb and Zn was evaluated. Bioconcentration factors (BCF) and plant-specific metal models (PSMM) developed from multivariate regressions were calculated. The explained variability of the models was from 19 to 64% and correlations between measured and predicted concentrations were between 0.43 and 0.90. The developed hop and rapeseed models are new in this field. Available models from literature showed inaccurate results, except for Cd; the modelling efficiency was mostly around zero. The use of interaction terms between parameters can significantly improve plant-specific models.
Show more [+] Less [-]Temporal-spatial distributions and ecological risks of perfluoroalkyl acids (PFAAs) in the surface water from the fifth-largest freshwater lake in China (Lake Chaohu) Full text
2015
Liu, Wen-Xiu | He, Wei | Qin, Ning | Kong, Xiang-Zhen | He, Qi-Shuang | Yang, Bin | Yang, Chen | Jorgensen, Sven Erik | Xu, Fu-Liu
To investigate the residues, compositions, distributions and potential ecological risks of perfluoroalkyl acids (PFAAs), water samples were collected seasonally between August 2011 and November 2012 from 20 sites in Lake Chaohu and its tributary rivers. The mean concentration of total PFAAs (TPFAAs) was 14.46 ± 6.84 ng/L. PFOA was the predominant contaminant (8.62 ± 4.40 ng/L), followed by PFBA (2.04 ± 1.16 ng/L) and PFHxA (1.23 ± 1.50 ng/L). The TPFAAs concentrations peaked in August 2012 in each area, except for the western river. The opposite spatial trends were found for PFOA and PFOS in both the lake and river areas. Except for PFOS and PFUdA, the levels of TPFAAs and PFAAs were significantly related to the composition of fluorescent dissolved organic matter (FDOM) but not related to total DOM expressed by dissolved organic carbon (DOC). The risk of PFOS determined by a species sensitivity distribution model was notably above that of PFOA.
Show more [+] Less [-]Quantitative evaluation of noncovalent interactions between polyphosphate and dissolved humic acids in aqueous conditions Full text
2015
Fang, Wei | Sheng, Guo-Ping | Wang, Long-Fei | Ye, Xiao-Dong | Yu, Han-Qing
As one kind of phosphorus species, polyphosphate (poly-P) is ubiquitous in natural environments, and the potential interactions between poly-P and humic substances in the sediments or natural waters would influence the fate of poly-P in the environments. However, the mechanism of the interactions has not yet been understood clearly. In this work, the characteristics and mechanisms of the interactions between humic acids (HA) and two model poly-P compounds with various chain lengths have been investigated. Results show that a stable polyphosphate-HA complex would be formed through the noncovalent interactions, and hydrogen bond might be the main driving force for the binding process, which might be formed between the proton-accepting groups of poly-P (e.g., PO and P–O−) and the oxygen containing functional groups in HA. Our findings implied that the presence of humic substances in natural waters, soils and sediments would influence the potential transport and/or mobility of environmental poly-P.
Show more [+] Less [-]CO2 dose–response functions for wheat grain, protein and mineral yield based on FACE and open-top chamber experiments Full text
2015
Pleijel, Håkan | Högy, Petra
Data from three Swedish open-top chamber and four German FACE experiments were combined to derive response functions for elevated CO2 (eCO2) effects on Cd, Zn, Mn, protein, grain yield, grain mass and grain number of wheat. Grain yield and grain number were increased by ∼6% and ∼7%, respectively, per 100 ppm CO2; the former effect was linked to plant nitrogen status. Grain mass was not influenced by eCO2, whereas Cd concentration was reduced. Unlike Zn, Mn and protein, effects on Cd yield were not related to effects on grain yield. Yields of Mn, Zn and (weakly) protein were positively affected by eCO2. For protein, grain yield, grain mass and grain number, the results were consistent among the FACE and OTC experiments. A key conclusion was that yields of essential nutrients were enhanced (Mn > Zn > protein), although less than grain yield, which would not be expected from a simple dilution model.
Show more [+] Less [-]Predicting exposure of wildlife in radionuclide contaminated wetland ecosystems Full text
2015
Stark, K. | Andersson, P. | Beresford, N.A. | Yankovich, T.L. | Wood, M.D. | Johansen, M.P. | Vives i Batlle, J. | Twining, J. | Keum, D.-K. | Bollhöfer, A. | Doering, C. | Ryan, B. | Grzechnik, M. | Vandenhove, H.
Many wetlands support high biodiversity and are protected sites, but some are contaminated with radionuclides from routine or accidental releases from nuclear facilities. This radiation exposure needs to be assessed to demonstrate radiological protection of the environment. Existing biota dose models cover generic terrestrial, freshwater, and marine ecosystems, not wetlands specifically. This paper, which was produced under IAEA's Environmental Modelling for Radiation Safety (EMRAS) II programme, describes an evaluation of how models can be applied to radionuclide contaminated wetlands. Participants used combinations of aquatic and terrestrial model parameters to assess exposure. Results show the importance of occupancy factor and food source (aquatic or terrestrial) included. The influence of soil saturation conditions on external dose rates is also apparent. In general, terrestrial parameters provided acceptable predictions for wetland organisms. However, occasionally predictions varied by three orders of magnitude between assessors. Possible further developments for biota dose models and research needs are identified.
Show more [+] Less [-]Aerosol deposition doses in the human respiratory tree of electronic cigarette smokers Full text
2015
Manigrasso, Maurizio | Buonanno, Giorgio | Fuoco, Fernanda Carmen | Stabile, Luca | Avino, Pasquale
Aerosols from eight e-cigarettes at different nicotine levels and flavoring were characterized as particle number size distributions in the range 5.6–560 nm by FMPS and CPC. Results were used to provide dosimetry estimates applying the MMPD model.Particle number concentrations varied between 3.26 × 109 and 4.09 × 109 part cm−3 for e-liquids without nicotine and between 5.08 × 109 and 5.29 × 109 part cm−3 for e-liquids with nicotine. No flavor effects were detected on particle concentration data. Particle size distributions were unimodal with modes between 107–165 nm and 165–255 nm, for number and volume metrics, respectively.Averagely, 6.25 × 1010 particles were deposited in respiratory tree after a single puff. Highest deposition densities and mean layer thickness of e-cigarette liquid on the lung epithelium were estimated at lobar bronchi.Our study shows that e-cigarette aerosol is source of high particle dose in respiratory system, from 23% to 35% of the daily dose of a no-smoking individual.
Show more [+] Less [-]Ambient air pollution, temperature and out-of-hospital coronary deaths in Shanghai, China Full text
2015
Dai, Jinping | Chen, Renjie | Meng, Xia | Yang, Changyuan | Zhao, Zhuohui | Kan, Haidong
Few studies have evaluated the effects of ambient air pollution and temperature in triggering out-of-hospital coronary deaths (OHCDs) in China. We evaluated the associations of air pollution and temperature with daily OHCDs in Shanghai, China from 2006 to 2011. We applied an over-dispersed generalized additive model and a distributed lag nonlinear model to analyze the effects of air pollution and temperature, respectively. A 10 μg/m3 increase in the present-day PM10, PM2.5, SO2, NO2 and CO were associated with increases in OHCD mortality of 0.49%, 0.68%, 0.88%, 1.60% and 0.08%, respectively. A 1 °C decrease below the minimum-mortality temperature corresponded to a 3.81% increase in OHCD mortality on lags days 0–21, and a 1 °C increase above minimum-mortality temperature corresponded to a 4.61% increase over lag days 0–3. No effects were found for in-hospital coronary deaths. This analysis suggests that air pollution, low temperature and high temperature may increase the risk of OHCDs.
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