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Association of urinary cadmium with risk of diabetes: a meta-analysis Texte intégral
2017
Li, Yujie | Zhang, Yun | Wang, Weijing | Wu, Yili
The association between urinary cadmium and diabetes risk remains controversial. PubMed, Web of Science, China National Knowledge Infrastructure, and Wanfang Data updated on 21 June 2016 were searched for eligible publications. Pooled odds ratio (OR) with 95% confidence interval (CI) of diabetes for highest versus lowest level of urinary cadmium was calculated by using fixed-effect model or random-effect model. Dose-response relationship between urinary cadmium and diabetes was estimated by restricted cubic spline. A total of nine studies with 28,691 participants were included in this meta-analysis. The pooled OR of diabetes for the highest versus lowest level of urinary cadmium was 1.02 (95% CI, 1.00, 1.05; I ² = 42.3%). In subgroup analysis, the ORs were 1.02 (95% CI 1.00, 1.05; I ² = 0.9%) for studies conducted in Asia and 1.11 (95% CI 0.88, 1.41; I ² = 86.3%) in America. For dose-response analysis, a linear relationship was found between urinary cadmium and the risk of diabetes (P fₒᵣ ₙₒₙₗᵢₙₑₐᵣ = 0.5856). For every l μg/g creatinine increment of urinary cadmium, the risk of diabetes increased by 16% (1.16, 95% CI 1.08, 1.25). This meta-analysis suggests that cadmium exposure might be significantly associated with prevalence of diabetes, but large prospective studies are needed to confirm this finding.
Afficher plus [+] Moins [-]Effects of different ratios of glucose to acetate on phosphorus removal and microbial community of enhanced biological phosphorus removal (EBPR) system Texte intégral
2017
Sun, Chloe Tse | Mo, Chuangrong | Li, Xiaoming | Zhang, Jian | An, Hongxue | Yang, Qi | Wang, Dongbo | Zhao, Jianwei | Zhong, Yu | Zeng, Guangming
In this study, the effects of different ratios of glucose to acetate on enhanced biological phosphorus removal (EBPR) were investigated with regard to the changes of intercellular polyhydroxyalkanoates (PHAs) and glycogen, as well as microbial community. The experiments were carried out in five sequencing batch reactors (SBRs) fed with glucose and/or acetate as carbon sources at the ratios of 0:100 %, 25:75 %, 50:50 %, 75:25 %, and 100:0 %. The experimental results showed that a highest phosphorus removal efficiency of 96.3 % was obtained with a mixture of glucose and acetate at the ratio of 50:50 %, which should be attributed to more glycogen and polyhydroxyvalerate (PHV) transformation in this reactor during the anaerobic condition. PCR-denaturing gradient gel electrophoresis (DGGE) analysis of sludge samples taken from different anaerobic/aerobic (A/O) SBRs revealed that microbial community structures were distinctively different with a low similarity between each other.
Afficher plus [+] Moins [-]Heterogeneous nano-Fe/Ca/CaO catalytic ozonation for selective surface hydrophilization of plastics containing brominated and chlorinated flame retardants (B/CFRs): separation from automobile shredder residue by froth flotation Texte intégral
2017
Mallampati, Srinivasa Reddy | Lee, Byoung Ho | Mitoma, Yoshiharu | Simion, Cristian
One method of weakening the inherently hydrophobic surface of plastics relevant to flotation separation is heterogeneous nano-Fe/Ca/CaO catalytic ozonation. Nano-Fe/Ca/CaO-catalyzed ozonation for 15 min efficiently decreases the surface hydrophobicity of brominated and chlorinated flame retardant (B/CFR)-containing plastics (such as acrylonitrile-butadienestyrene (ABS), high-impact polystyrene (HIPS), and polyvinyl chloride (PVC)) in automobile shredder residue (ASR) to such an extent that their flotation ability is entirely depressed. Such a hydrophilization treatment also stimulates the ABS, HIPS, and PVC surface roughness, wetting of the surface, and the thermodynamic equilibrium conditions at the surface and ultimately changes surface polarity. SEM-EDS, AFM, and XPS analyses of the PVC and ABS surfaces demonstrated a marked decrease in [Cl/Br] and a significant increase in the number of hydrophilic groups, such as C–O, C=O, and (C=O)–O. Under froth flotation conditions at 50 rpm, about 99.5 % of ABS and 99.5 % of HIPS in ASR samples settled out, resulting in a purity of 98 and 98.5 % for ABS and HIPS in ASR samples, respectively. Furthermore, at 150 rpm, we also obtained 100 % PVC separation in the settled fraction, with 98 % purity in ASR. Total recovery of non-B/CFR-containing plastics reached nearly 100 % in the floating fraction. The amount of nano-Fe/Ca/CaO reagent employed during ozonation is very small, and additional removal of surface contaminants from the recycled ASR plastic surfaces by ozonation makes the developed process simpler, greener, and more effective.
Afficher plus [+] Moins [-]The effect of low-molecular-weight organic acids on copper toxicity in E. fetida in an acute exposure system Texte intégral
2017
Zhou, Chuifan | Huang, Meiying | Yu, Jiaoda | Li, Ying | Liu, Aiqin
In the present study, the effects of low-molecular-weight organic acids (OAs) on the toxicity of copper (Cu) to the earthworm Eisenia fetida (E. fetida) were investigated in a simulated soil solution. We exposed E. fetida to soil solution containing Cu and a variety of OAs (acetic acid, oxalic acid, citric acid, and EDTA). We found that the addition of OAs reduced the toxicity of Cu to E. fetida, where the reduction was strongest in EDTA and weakest in acetic acid. These compounds decreased the mortality rate of E. fetida that were exposed to Cu and reduced levels of antioxidant enzymes and malondialdehyde to unexposed control levels. E. fetida were exposed to Cu with OAs had reduced Cu²⁺, which were likely caused by Cu forming complexes with the OAs, reducing the availability of Cu. The presence of OAs also reduced Cu-induced damage on earthworm cellular ultrastructures and changed the subcellular distribution of Cu. These results demonstrated that OAs could reduce the toxicity, as well as the bioavailability, of heavy metals in soil solutions where both OAs and heavy metals often coexist.
Afficher plus [+] Moins [-]Differences in the accumulation and tissue distribution of Pb, Cd, and Cu in Mediterranean mussels (Mytilus galloprovincialis) exposed to single, binary, and ternary metal mixtures Texte intégral
2017
García-Navarro, José A. | Franco Vidal, Lorena | Romero, Diego
Heavy metals often accumulate in complex mixtures in the environment and are currently a source of concern in many marine ecosystems. Pb, Cd, and Cu are regarded as priority hazardous metals due to their great persistence, bioaccumulation, and toxicity. The aim of the present study was to investigate the tissue accumulation and distribution of these heavy metals in Mediterranean mussels (Mytilus galloprovincialis) exposed to binary and ternary mixtures of metals as opposed to only single exposures. Heavy metal concentrations in the digestive gland, gills, and the other soft tissues were determined by inductively coupled plasma optical emission spectrometry (ICP-OES), and the distribution of each metal was analyzed according to compartments. The concentrations of Pb, Cd, and Cu increased significantly in the group exposed to the ternary mixture; however, there was no common response pattern to exposure in single and binary mixtures. Above all, the metals concentrated in the digestive gland, although the percentages of each element varied between compartments and varied between tissues according to the treatment.
Afficher plus [+] Moins [-]The endophytic bacterium Serratia sp. PW7 degrades pyrene in wheat Texte intégral
2017
Zhu, Xuezhu | Wang, Wanqing | Crowley, David E. | Sun, Kai | Hao, Shupeng | Waigi, Michael Gatheru | Gao, Yanzheng
This research was conducted to isolate polycyclic aromatic hydrocarbon-degrading (PAH-degrading) endophytic bacteria and investigate their potential in protecting plants against PAH contamination. Pyrene-degrading endophytic bacteria were isolated from plants grown in PAH-contaminated soil. Among these endophytic bacteria, strain PW7 (Serratia sp.) isolated from Plantago asiatica was selected to investigate the suppression of pyrene accumulation in Triticum aestivum L. In the in vitro tests, strain PW7 degraded 51.2% of the pyrene in the media within 14 days. The optimal biodegradation conditions were pH 7.0, 30 °C, and MS medium supplemented with additional glucose, maltose, sucrose, and peptones. In the in vivo tests, strain PW7 successfully colonized the roots and shoots of inoculated (E⁺) wheat plants, and its colonization decreased pyrene accumulation and pyrene transportation from roots to shoots. Remarkably, the concentration of pyrene in shoots decreased much more than that in roots, suggesting that strain PW7 has the potential for protecting wheat against pyrene contamination and mitigating the threat of pyrene to human health via food consumption.
Afficher plus [+] Moins [-]Forecasting residential electricity demand in provincial China Texte intégral
2017
Liao, Hua | Liu, Yanan | Gao, Yixuan | Hao, Yu | Ma, Xiao-Wei | Wang, Kan
In China, more than 80% electricity comes from coal which dominates the CO2 emissions. Residential electricity demand forecasting plays a significant role in electricity infrastructure planning and energy policy designing, but it is challenging to make an accurate forecast for developing countries. This paper forecasts the provincial residential electricity consumption of China in the 13th Five-Year-Plan (2016–2020) period using panel data. To overcome the limitations of widely used predication models with unreliably prior knowledge on function forms, a robust piecewise linear model in reduced form is utilized to capture the non-deterministic relationship between income and residential electricity consumption. The forecast results suggest that the growth rates of developed provinces will slow down, while the less developed will be still in fast growing. The national residential electricity demand will increase at 6.6% annually during 2016–2020, and populous provinces such as Guangdong will be the main contributors to the increments.
Afficher plus [+] Moins [-]The longevity of para-aminopropiophenone (PAPP) wild dog baits and the implications for effective and safe baiting campaigns Texte intégral
2017
Gentle, Matthew | Speed, James | Allen, Benjamin L. | Harris, Stacy | Haapakoski, Hellen | Bell, Kerry
The longevity of para-aminopropiophenone (PAPP) wild dog baits and the implications for effective and safe baiting campaigns Texte intégral
2017
Gentle, Matthew | Speed, James | Allen, Benjamin L. | Harris, Stacy | Haapakoski, Hellen | Bell, Kerry
Considerable effort goes into mitigating the impacts caused by invasive animals and prohibiting their establishment or expansion. In Australia, management of wild dogs (Canis lupus dingo and their hybrids) and their devastating impacts is reliant upon poison baiting. The recent release of baits containing the humane toxin para-aminopropiophenone (PAPP) offers potential improvements for control of wild dogs, but little is known about the environmental persistence of PAPP in manufactured baits that could be used to inform best practice guidelines. We investigated the degradation rate of PAPP wild dog baits (DOGABAIT™) under typical field usage and storage conditions in north-eastern Australia and calculated optimal deployment and withholding periods. The PAPP content of buried baits declines faster than surface-laid baits, but both presentations retained lethal doses to wild and domestic dogs for considerable periods (6–16 weeks). Domestic or working dogs should be suitably restrained or excluded from baited areas for extended periods, particularly under dry conditions, to minimise poisoning risk. The period of persistence of PAPP baits may provide opportunities to improve the duration or longer term efficacy of baiting campaigns, but care is needed to protect domestic and working dogs to ensure responsible and safe use.
Afficher plus [+] Moins [-]The longevity of para-aminopropiophenone (PAPP) wild dog baits and the implications for effective and safe baiting campaigns Texte intégral
2017
Gentle, Matthew N. | Speed, James | Allen, Benjamin L. | Harris, Stacy | Haapakoski, Hellen | Bell, Kerry L.
Considerable effort goes into mitigating the impacts caused by invasive animals and prohibiting their establishment or expansion. In Australia, management of wild dogs (Canis lupus dingo and their hybrids) and their devastating impacts is reliant upon poison baiting. The recent release of baits containing the humane toxin para-aminopropiophenone (PAPP) offers potential improvements for control of wild dogs, but little is known about the environmental persistence of PAPP in manufactured baits that could be used to inform best practice guidelines. We investigated the degradation rate of PAPP wild dog baits (DOGABAIT™) under typical field usage and storage conditions in north-eastern Australia and calculated optimal deployment and withholding periods. The PAPP content of buried baits declines faster than surface-laid baits, but both presentations retained lethal doses to wild and domestic dogs for considerable periods (6–16 weeks). Domestic or working dogs should be suitably restrained or excluded from baited areas for extended periods, particularly under dry conditions, to minimise poisoning risk. The period of persistence of PAPP baits may provide opportunities to improve the duration or longer term efficacy of baiting campaigns, but care is needed to protect domestic and working dogs to ensure responsible and safe use.
Afficher plus [+] Moins [-]Comparison of normal and dusty day impacts on fractional exhaled nitric oxide and lung function in healthy children in Ahvaz, Iran Texte intégral
2017
Neisi, Abdolkazem | Vosoughi, Mehdi | Idani, Esmaeil | Goudarzi, Gholamreza | Takdastan, Afshin | Babaei, Ali Akbar | Ankali, Kambiz Ahmadi | Hazrati, Sadegh | Shoshtari, Maryam Haddadzadeh | Mirr, Iman | Maleki, Heidar
Children are the vulnerable group at risk of adverse health effects related to air pollution due to dust storm in Ahvaz. The purpose of this study was to compare the values of fractional exhaled nitric oxide (FENO) and lung functions as parameters of adverse health effects of particulate matter (PM) in dusty and normal (non-dusty) days in elementary schoolchildren. The study was conducted among elementary school students in Ahvaz. The healthy elementary schoolchildren (N = 105) were selected from different districts for FENO and lung function sampling during the dusty and normal days. The values of PM₁₀ and PM₂.₅ during dusty days were higher than during normal days. Mean values of FENO during the normal and dusty days were 14.23 and 20.3 ppb, respectively, and the difference between these values was statistically significant (p < 0.05). Lung function results showed a statistically significant difference between the mean values of forced vital capacity during the dusty and normal days (p < 0.05). The results revealed a significant difference both in the values of inflammatory biomarker and in the lung function tests in dusty and normal days. Based on our results, fractional exhaled nitric oxide could be a useful short-term biomarker of particulate pollution effect coupled with spirometry.
Afficher plus [+] Moins [-]Rosmarinus officinalis L. ameliorates titanium dioxide nanoparticles and induced some toxic effects in rats’ blood Texte intégral
2017
Grissa, Intissar | Ezzi, Lobna | Chakroun, Sana | Mabrouk, Abir | Saleh, Azer Ben | Braham, Hamadi | Haouas, Zohra | Cheikh, Hassen Ben
Titanium dioxide nanoparticles (TiO₂ NPs) have been widely used as a white pigment in food and drugs. The most important route of human exposure to TiO₂ is through food and drug products containing TiO₂ additives. This study investigates the efficacy of an oral traditional use of rosemary extract in ameliorating some toxic effects induced on blood of TiO₂ NP-intoxicated rats. Rats were given rosemary extract via intragastric administration 1 h before the intragastric administration of 100 mg/kg/day TiO₂ NPs (10 nm) for 60 days. TiO₂ NPs significantly increased serum cholesterol, glucose, and triglyceride levels of rats. They also induced significant oxidative stress and inflammatory and caused DNA damage in peripheral blood leukocytes. The rosemary extract appears to have a significant protective effect by lowering glucose level properties, restoring the lipid profile and showing an antioxidative, anti-inflammatory, and antigenotoxic properties against TiO₂ NPs toxicity. In conclusion, this study gives an encouraging scientific basis for consumers of rosemary leaves to keep on with this culinary habit.
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