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1.
Environmental Science and Pollution Research - There is mixed evidence surrounding the relationship between tobacco use and COVID-19 infection/progression. The current study investigates beliefs...  相似文献   
2.
Environmental Science and Pollution Research - Biochar has strong potential to improve nitrogen (N) use efficiency in both agricultural and horticultural systems. Biochar is usually co-applied with...  相似文献   
3.
Environmental Science and Pollution Research - This study aimed to determine the effect of land-use changes on the non-carcinogenic health risk of nitrate ion exposure of underground drinking water...  相似文献   
4.
Noroviruses are one of important agents that cause acute viral gastroenteritis worldwide. These viruses are belonging to Caliciviridae family and are genetically diverse. To date, there is no valuable data about prevalence of norovirus infection and the dominant genogroup/genotype among Iranian population. The objective of this study was to determine the frequency of norovirus infection in Iranian patients with gastroenteritis referred to three hospitals of Tehran and to specify the dominant genogroup/genotype of this virus among our study population. A total of 293 patients with acute gastroenteritis were included in the study. Detection of norovirus was performed using RT-PCR method and confirmed by direct sequencing with specific designed primers for capsid region of norovirus genome. Phylogenetic analysis was performed using the neighbor-joining method. Norovirus strains identified in our study were subsequently categorized according to previously defined genogroup/genotypes. Of these, norovirus GII was dominant genogroup. Sixty-five percent (17 of 26) of positive samples were determined as GII and 35% (9 of 26) were determined as GI, respectively, in 2008–2009. And among 8 sequenced strains of genogroup II the most frequent genotype was GII.3. The results of this study indicated that norovirus must be considered as one of the infectious causes of acute gastroenteritis among Iranian population. We also found that GII.3 is more prevalent in our study population. To the best of our knowledge there is limited data about the role of noroviruses in children and adults’ acute gastroenteritis among Iranian patients and this prevalence and genotyping report of norovirus infection could be remarkable for further studies.  相似文献   
5.
Natural aggregates (NA) are crushed and processed in crushing plants after the extraction stage in quarries. In the present study, the aggregates are divided into three scenarios, depending on the production methods. The first scenario considers the production of NA, the second scenario deals with the production of recycled aggregates (RA) with respect to construction and demolition waste, and the third scenario, which is a hybrid scenario, handles the combination of NA and RA by assuming a 50% mixing percentage. In this research, we assess the environmental impacts on the production of aggregates via each scenario, using life cycle assessment; in addition, energy consumption and CO2 emissions are considered as the environmental variables. We conclude that Iran’s current policy with an annual energy consumption of 1.48 million tons of oil equivalent (toe) can have a footprint of 2.88 million tons of CO2 eq emissions per year (the first scenario). Achieving 30 and 36% reduction in annual energy consumption and CO2 emissions, respectively, by the third scenario compared to the first scenario indicates the destructive effect of the first scenario from the environmental outlook.  相似文献   
6.
Titanium dioxide nanoparticles (TiO2 NPs) are widely used for their whiteness and opacity in several applications such as food colorants, drug additives, biomedical ceramic, and implanted biomaterials. Research on the neurobiological response to orally administered TiO2 NPs is still limited. In our study, we investigate the effects of anatase TiO2 NPs on the brain of Wistar rats after oral intake. After daily intragastric administration of anatase TiO2 NPs (5–10 nm) at 0, 50, 100, and 200 mg/kg body weight (BW) for 60 days, the coefficient of the brain, acethylcholinesterase (AChE) activities, the level of interleukin 6 (IL-6), and the expression of glial fibrillary acidic protein (GFAP) were assessed to quantify the brain damage. The results showed that high-dose anatase TiO2 NPs could induce a downregulated level of AChE activities and showed an increase in plasmatic IL-6 level as compared to the control group accompanied by a dose-dependent decrease inter-doses, associated to an increase in the cerebral IL-6 level as a response to a local inflammation in brain. Furthermore, we observed elevated levels of immunoreactivity to GFAP in rat cerebral cortex. We concluded that oral intake of anatase TiO2 NPs can induce neuroinflammation and could be neurotoxic and hazardous to health.  相似文献   
7.
The aim of present study was to investigate the quality of the produced effluent from different units of the Iran Central Iron Ore in Bafq city and comparison of effluent with the standards. This study presents the physicochemical and biological parameters data of effluent of three Sequencing batch reactors (SBR) with a capacity of 160 m3?d?1. Most common parameters include pH, total suspended solids (TSS), total nitrogen (TN), total phosphorus (TP), biochemical oxygen demand (BOD5), chemical oxygen demand (COD), heavy metals, and total coliforms and fecal coliforms as biological indicators. Then, for each SBR system, the average of each parameter was determined, and results were compared with the standard recommended by the Iranian Environmental Protection Agency. Based on the results, some of the parameters, including BOD5, COD, and TSS in the wastewater treatment plant (WWTP) effluent, are higher than the permitted amount for discharge to the surface water. Considering the BOD5, COD, and TSS concentration in WWTPs, the treated wastewater is only suitable for agricultural and irrigation use. Therefore, wastewater produced by Iran Central Iron Ore Co. will need additional treatment to achieve standard quality of water before discharge in surface water and adsorbent well.  相似文献   
8.
During revegetation, the maintenance of soil carbon (C) pools and nitrogen (N) availability is considered essential for soil fertility and this study aimed to evaluate contrasting methods of site preparation (herbicide and scalping) with respect to the effects on soil organic matter (SOM) during the critical early establishment phase. Soil total C (TC), total N (TN), hot-water extractable organic C (HWEOC), hot-water extractable total N (HWETN), microbial biomass C and N (MBC and MBN), total inorganic N (TIN) and potentially mineralizable N (PMN) were measured over 53 weeks. MBC and MBN were the only variables affected by herbicide application. Scalping caused an immediate reduction in all variables, and the values remained low without any sign of recovery for the period of the study. The impact of scalping on HWETN and TIN lasted 22 weeks and stabilised afterwards. MBC and MBN were affected by both herbicide and scalping after initial treatment application and remained lower than control during the period of the study but did not decrease over time. While scalping had an inevitable impact on all soil properties that were measured, that impact did not worsen over time, and actually improved plant growth (unpublished data) while reducing site establishment costs. Therefore, it provides a useful alternative for weed control in revegetation projects where it is applied only once at site establishment and where SOM would be expected to recover as canopy closure is obtained and nutrient cycling through litterfall commences.  相似文献   
9.
Environmental Science and Pollution Research - Antibiotics, as one of the emerging pollutants, are non-biodegradable compounds and long-term exposure to them may affect endocrine, hormonal, and...  相似文献   
10.
This paper investigated the durability and mechanical properties of landfill leachate collection HDPE pipes which had been made of different weight percent amounts of virgin and reprocessable HDPE compounds (VC and RC). Durability is reported base on the chemical properties, obtained through oxidative induction time (OIT) and melt flow index (MFI) measurements, at the temperature of 50 °C and over a period of 12 months immersion in a synthetic leachate. Mechanical properties are also described according to tensile and pressure tests which had been conducted on the pipes samples. All of the factors were examined had been affected by the addition of RC, but for the special combination the antioxidant depletion was significantly affected by the experimental aging condition and no important changes had been observed in the other pipe properties. The results from OIT tests indicate that the rate of antioxidant depletion is reduced by an increase in the weight percent amounts of RC, during the experimental aging condition. This reduction is probably attributed to the extraction of antioxidants from RC in their recovery process. Finally, although these results are related to the particular HDPE compound, antioxidant formulation and condition examined, but it can be said that the use of clean own reprocessable material for the production of landfill leachate pipes shall be permitted without limitations.  相似文献   
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