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Environment, Development and Sustainability - This paper explores the advantages of international trade and foreign direct investment (FDI), which can be the main factors of transferring technology... 相似文献
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Farideh Golbabaei Maryam Mamdouh Keramat Nouri Jelyani Seyed Jamaleddin Shahtaheri 《International journal of occupational safety and ergonomics》2005,11(3):283-289
Exposure to methyl methacrylate (MMA), total dust and health symptoms were investigated in 20 dental laboratories located in Tehran, Iran. Time-weighted average (TWA) of MMA and peak concentrations were determined, using XAD-2 tubes followed by GC-FID analysis. Total dusts were evaluated gravimetrically. Health symptoms were asked using a questionnaire. TWA for technicians with direct and indirect exposure to MMA were 327.28 +/- 79.42 and 282.9 +/- 41.84 mg/m3, respectively. Peak concentration of MMA for those technicians were 337.0 +/- 36.81 and 328.88 +/- 45.40 mg/m3, respectively. There were no significant differences between TWA of MMA and peak concentration in different weekly workdays; however, within-day variations were observed (P < .05). TWA of MMA and peak concentration correlation with the laboratory volume were 0.61-0.65. Dust exposure of technicians was 2.35 +/- 2.70 mg/m3. Cough and skin dryness were the common health symptoms. Smoking and asbestos exposure history were factors influencing cough prevalence (p < .05). It is concluded that the current Short-Term Exposure Limit (STEL) is not low enough to protect technicians against the adverse effects caused by MMA. 相似文献
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Taghavizadeh Yazdi Mohammad Ehsan Amiri Mohammad Sadegh Nourbakhsh Fahimeh Rahnama Mostafa Forouzanfar Fatemeh Mousavi Seyed Hadi 《Environmental science and pollution research international》2021,28(21):26359-26379
Environmental Science and Pollution Research - Heat shock proteins (HSPs) are a family of proteins that are expressed by cells in reply to stressors. The changes in concentration of HSPs could be... 相似文献
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Sara Romani Seyed Reza Mohebbi Seyed Masoud Hosseini Pedram Azimzadeh Mohsen Vahedi Faramarz Derakhshan Mohammad Reza Zali 《Food and environmental virology》2012,4(1):1-5
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
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Hosseini Alhashemi A Karbassi A Hassanzadeh Kiabi B Monavari SM Sekhavatjou MS 《Environmental monitoring and assessment》2012,184(4):1865-1878
In the present research, accumulation of Cd, Co, Cr, Cu, Mn, Ni, Pb, V, and Zn were determined in sediments and fillet, liver,
kidney, gonads, and gills of three commonly fish species in the largest wetland ecosystem that is located in southwest of
Iran; Shadegan wetland. Shadegan is one of the most important wetland that posses various fauna and flora but suffers inputs
from agricultural and industrial activities. So, sediment samples and fish species including Barbus grypus, Barbus sharpeyi, and Cyprinus carpio were collected during winter 2009. Results showed that mean concentrations of trace elements (except Ni and Co) were high
in liver and gills of B. grypus. Also trace elements had the most accumulation in liver of B. sharpeyi except for Cd (0.26 mg kg − 1 d.w.) and Mn (13.45 mg kg − 1 d.w.) that were high in gills. Beside, kidney is determined as target tissue for Ni and V in B. grypus and for Pb in C. carpio, due to their high concentration. Zn levels in all tissues of C. carpio showed the highest concentrations in comparison to other fish species. Generally, accumulations of most of the studied elements
in B. grypus and B. sharpeyi were higher in females than in males, while in fillet and gonads of C. carpio, this trend was inverted. Bioaccumulation factors (BAFs) were determined for different tissues of fish species with respect
to elemental concentrations in sediment. BAFs results indicated that Zn, Pb, and Cu have higher BAF than other elements. Also
this investigation demonstrated that trace elements have different affinities with condition factor of studied fish species.
Gonadosomatic index (GSI) and Pb showed positive correlation together in both B. sharpeyi and B. grypus, respectively, in females and males. Moreover, females of C. carpio showed significantly positive relation of GSI and all studied elements. 相似文献
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Sakizadeh M Esmaeili Sari A Abdoli A Bahramifar N Hashemi SH 《Environmental monitoring and assessment》2012,184(5):3231-3237
The Anzali Wetland is one of the most important ecosystems in the north of Iran, and parts of it were registered as a Ramsar
site in 1975. However, even though, due to many problems, including eutrophication produced by inflow of excess nutrients
and organic materials, the wetland was also listed on the Montreux Record indicating the need to take urgent remedial action.
This study was conducted to study the levels of polychlorinated biphenyls (PCBs) and total mercury (THg) in two fish species
(Esox lucius and Carassius auratus) as bio-indicators of the ecosystem condition in eastern part of Anzali Wetland. The sampling was carried out in six different
periods between years 2009 and 2010. The results showed that the amounts of PCBs in the muscle of northern pike were below
the detection limit of gas chromatography, whereas the average concentration in goldfish was 0.449 mg/kg wet weight. Some
possible reasons for the higher levels of PCBs in goldfish in comparison with pike have been discussed. No significant (p < 0.05) correlation was observed between PCBs and biological factors (weight, length, lipid content) for both species. On
the other hand, the mean concentration of THg in the muscle of pike and goldfish were 182.22 and 75.27 ng/g dry weight, respectively.
Although these concentrations were below US-EPA criterion for human consumption (0.3 mg/kg), it pointed up a significant deterioration
of the ecosystem condition during the past years. Finally, statistical analysis revealed a significant correlation between
THg with weight and an insignificant correlation with length for pike specimens. 相似文献
9.
Monavari SM Omrani GA Karbassi A Raof FF 《Environmental monitoring and assessment》2012,184(4):1841-1846
Environment problems associated with the generation of waste are part of societal changes where households play an important
role. These societal changes influence the size, structure and characteristic of given households. For the effective planning
of solid-waste handling infrastructure, it is essential to know the quantity of waste generation and its composition. This
paper presents the findings of a study carried out in an urban municipal area in Iran to determine the household solid-waste
generation rate and waste composition based on field surveys and to determine the related socioeconomic parameters. The dependent
variables were waste generation and composition, and independent variables were family size, family employment, age, number
of room and education. Over 400 sample households were selected for the study using a stratified random sampling methodology
and from five different socioeconomic groups. Waste collected from all groups of households were segregated and weighted.
Waste generation rate was 5.4 kg/household/day. Household solid waste comprised of ten categories of wastes and with the largest
component (76.9%). The generation and composition of household solid waste were correlated with family size, education level
and households income. This paper adequately suggests new insights concerning the role of socioeconomic parameters in affecting
the generation of household waste. 相似文献
10.
Behroz Abdoli Seyed Ali MirHassani Farnaz Hooshmand 《Environmental science and pollution research international》2017,24(27):21610-21624
Because of the harmful effects of greenhouse gas (GHG) emitted by petroleum-based fuels, the adoption of alternative green fuels such as biodiesel and compressed natural gas (CNG) is an inevitable trend in the transportation sector. However, the transition to alternative fuel vehicle (AFV) fleets is not easy and, particularly at the beginning of the transition period, drivers may be forced to travel long distances to reach alternative fueling stations (AFSs). In this paper, the utilization of bi-fuel vehicles is proposed as an operational approach. We present a mathematical model to address vehicle routing problem (VRP) with bi-fuel vehicles and show that the utilization of bi-fuel vehicles can lead to a significant reduction in GHG emissions. Moreover, a simulated annealing algorithm is adopted to solve large instances of this problem. The performance of the proposed algorithm is evaluated on some random instances. 相似文献