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91.
Environmental Science and Pollution Research - Chemical warfare (CW) agents are toxic synthetic chemicals that affect human’s health, and sulfur mustard (SM) is a well-known chemical weapon...  相似文献   
92.

The novel SARS-CoV-2 outbreak was declared as pandemic by the World Health Organization (WHO) on March 11, 2020. Understanding the airborne route of SARS-CoV-2 transmission is essential for infection prevention and control. In this study, a total of 107 indoor air samples (45 SARS-CoV-2, 62 bacteria, and fungi) were collected from different wards of the Hajar Hospital in Shahrekord, Iran. Simultaneously, bacterial and fungal samples were also collected from the ambient air of hospital yard. Overall, 6 positive air samples were detected in the infectious 1 and infectious 2 wards, intensive care unit (ICU), computed tomography (CT) scan, respiratory patients’ clinic, and personal protective equipment (PPE) room. Also, airborne bacteria and fungi were simultaneously detected in the various wards of the hospital with concentrations ranging from 14 to 106 CFU m?3 and 18 to 141 CFU m?3, respectively. The highest mean concentrations of bacteria and fungi were observed in respiratory patients’ clinics and ICU wards, respectively. Significant correlation (p < 0.05) was found between airborne bacterial concentration and the presence of SARS-CoV-2, while no significant correlation was found between fungi concentration and the virus presence. This study provided an additional evidence about the presence of SARS-CoV-2 in the indoor air of a hospital that admitted COVID-19 patients. Moreover, it was revealed that the monitoring of microbial quality of indoor air in such hospitals is very important, especially during the COVID-19 pandemic, for controlling the nosocomial infections.

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93.
The Aryl hydrocarbon receptor (AhR)-repressor (AhRR) is a regulator of the AhR pathway, which plays an important role in xenobiotic and reactive oxygen species (ROS) metabolism. Total antioxidant capacity (TAC) is a major factor in semen quality that protects sperm against ROS stress. Malondialdehyde (MDA) is the indicator of lipid peroxidation damage that is occurred due to ROSs. In this study, we determined and compared the MDA and TAC levels of infertile men’s semen and blood plasma regarding genotype groups of AhRR-c.565C>G transversion. Semen and blood samples of 123 infertile males were collected from the Fatemeh Zahra IVF Centre, Babol, Iran. TAC and MDA levels of seminal and blood plasma were measured by TBARS and FRAP methods, respectively. Cases were genotyped by the PCR-RFLP method. The frequency of c.565C>G genotypes was determined as CC (34.14%), CG (55.28%) and GG (10.58%). Mean levels of TAC μm/L and MDA nmol/mL in semen plasma of CC, CG and GG groups were (1365.7, 1.28), (1542.8, 1.51) and (1860.2, 0.82), respectively. Also, mean levels of TAC μm/L and MDA nmol/mL in blood plasma samples in CC, CG and GG genotypes were (806.14, 1.168), (727.1, 1.006) and (635.7, 0.83), respectively. Comparison of marker levels between genotypes revealed that the TAC level of semen plasma in the GG genotype was significantly higher than its level in the CC group (p < 0.05). Our findings showed that in seminal plasma of infertile men with the GG genotype of AhRR-c.565C>G transversion, the level of total antioxidant capacity is significantly higher in comparison with the CC genotype. Then, the G allele of AhRR-c.565C>G transversion may have a role in the increase in antioxidant capacity of seminal plasma.  相似文献   
94.
In this research, a microfunnel-assisted headspace liquid-phase microextraction technique has been used in combination with hydride generation to determine arsenic (As) by UV–Vis spectrophotometry. The method is based on the reduction of As to arsine (AsH3) in acidic media by sodium tetrahydroborate (NaBH4) followed by its subsequent reaction with silver diethyldithiocarbamate (AgDDC) to give an absorbing complex at 510 nm. The complexing reagent (AgDDC) has been dissolved in a 1:1 (by the volume ratio) mixture of chloroform/chlorobenzene microdroplet and exposed to the generated gaseous arsine via a reversed microfunnel in the headspace of the sample solution. Several operating parameters affecting the performance of the method have been examined and optimized. Acetonitrile solvent has been added to the working samples as a sensitivity enhancement agent. Under the optimized operating conditions, the detection limit has been measured to be 0.2 ng mL?1 (based on 3sb/m criterion, n b?=?8), and the calibration curve was linear in the range of 0.5–12 ng mL?1. The relative standard deviation for eight replicate measurements was 1.9 %. Also, the effects of several potential interferences have been studied. The accuracy of the method was validated through the analysis of JR-1 geological standard reference material. The method has been successfully applied for the determination of arsenic in raw and spiked soft drink and water samples with the recoveries that ranged from 91 to 106 %.  相似文献   
95.
96.
Coastal lagoon ecosystems are vulnerable to eutrophication, which leads to the accumulation of nutrients from the surrounding watershed over the long term. However, there is a lack of information about methods that could accurate quantify this problem in rapidly developed countries. Therefore, various statistical methods such as cluster analysis (CA), principal component analysis (PCA), partial least square (PLS), principal component regression (PCR), and ordinary least squares regression (OLS) were used in this study to estimate total organic matter content in sediments (TOM) using other parameters such as temperature, dissolved oxygen (DO), pH, electrical conductivity (EC), nitrite (NO2), nitrate (NO3), biological oxygen demand (BOD), phosphate (PO4), total phosphorus (TP), salinity, and water depth along a 3-km transect in the Gomishan Lagoon (Iran). Results indicated that nutrient concentration and the dissolved oxygen gradient were the most significant parameters in the lagoon water quality heterogeneity. Additionally, anoxia at the bottom of the lagoon in sediments and re-suspension of the sediments were the main factors affecting internal nutrient loading. To validate the models, R2, RMSECV, and RPDCV were used. The PLS model was stronger than the other models. Also, classification analysis of the Gomishan Lagoon identified two hydrological zones: (i) a North Zone characterized by higher water exchange, higher dissolved oxygen and lower salinity and nutrients, and (ii) a Central and South Zone with high residence time, higher nutrient concentrations, lower dissolved oxygen, and higher salinity. A recommendation for the management of coastal lagoons, specifically the Gomishan Lagoon, to decrease or eliminate nutrient loadings is discussed and should be transferred to policy makers, the scientific community, and local inhabitants.  相似文献   
97.
98.
Efficient use of energy helps to achieve increased production and productivity and contributes to the economy, profitability, and competitiveness of agricultural sustainability of rural communities. Evaluation of wheat and barley production systems in view of energy balance was conducted in Khorasan Razavi Province, Iran. Data were collected by using a face-to-face questionnaire from wheat and barley fields in 2011. Results revealed that total energy input for wheat was 51,040 MJ ha?1 and for barley 44,866; in wheat and barley systems, renewable energy was consumed by 25.43 and 23.53 %, while non-renewable energy was consumed by 74.57 and 76.47 %, respectively. Energy use efficiency, energy productivity, and net energy were 1.7 kg MJ?1, 0.088 kg MJ?1, and 35,987 MJ ha?1 in wheat system and 1.83 kg MJ?1, 0.092 kg MJ?1, and 33,833 MJ ha?1 in barley system, respectively. Energy intensiveness in wheat fields (61.84 MJ $?1) was higher than in barley fields (58.71 MJ $?1). Also, benefit-to-cost ratio in wheat system (1.59) was higher than in barley system (1.35). In general, production in barley fields was more sustainable than wheat production because, in view of ecological indices such as amount of energy use and renewable energy consumption, it was more environment-friendly production.  相似文献   
99.
Journal of Polymers and the Environment - In this study, composite packaging films were produced from relatively inexpensive materials including Whey protein isolate (WPI) and Persian gum (PG),...  相似文献   
100.
Environment, Development and Sustainability - Indigenous knowledge about climate change that makes adaptability necessary by coping strategies leads to the sustainability of nomadic livelihoods....  相似文献   
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