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Microplastics (MP) have been retrieved from settled dusts and rainfall collected monthly over a period of a year and daily over an additional period of ten days in the city of Shiraz and at an elevated remote site (Mount Derak) in Iran. Total monthly deposition ranged from about 1000 to 3500 MP m-2 at Shiraz and about 200 to 600 MP m-2 at Mount Derak, with greater deposition taking place during the dry months (June to November) than in months when precipitation events occurred. Overall, MP deposition was dominated by dry deposition, with precipitation appearing to washout MP and inhibit local resuspension of material by dampening the ground. The majority of MP in dust and precipitation (>99%) was of a fibrous nature, with the finest particles measured (

The freshwater Hashilan Wetland is an Iranian national heritage in Kermanshah Province which is planned to be registered as a World Heritage site because of its uniqueness in Iran and the neighboring countries. However, no comprehensive investigation on microplastics pollution in the sediment and water is available in the literature to help to preserve the aquatic environment. Thus, sediment and water samples were collected at 16 stations of the wetland and the extracted microplastics were characterized using visual identification, fluorescence and polarized lights, SEM-EDX, and μ -Raman methods. The results indicated presence of microplastic particles in Hashilan Wetland samples. A total of 71 microplastic particles were found in the sediments. The highest number of microplastics were observed close to roads, agricultural fields and tourist centers; however, no particle was observed in the control stations far from the aforementioned places. Cluster analysis showed a significant correlation between microplastic concentration and the clay fraction. Regarding the microplastic shape, Fibrous microplastics were the most frequent (>90%) in water and sediment samples. About 38.03% and 33.33% of the found microplastic particles are smaller than 100 μ m in the sediment and water, respectively. Classifying the microplastics according to their color result in the decreasing order of black/gray (47.88%) > blue/green (33.8%) > red/pink (18.31%) in the sediments and blue/green (66.67%) > red/pink (33.33%) in the waters. The detected microplastics in Hashilan water and sediment were polyethylene (PE), polypropylene (PP), polystyrene (PS) polymer. Positive matrix factorization (PMF) based on IMPROVE program was run and the results demonstrated relatively similar behaviors of microplastic particles and some potentially toxic elements including Pb, Zn, Cu, and Fe together with the percentage of organic matter and clay fraction in the sediments.

We describe a magnetic nanocomposite that consists of Fe3O4/carbon nanosphere/polypyrrole (Fe3O4/CNS/PPy). The synthesized nanocomposites were characterized by scanning electron microscopy, transmission electron microscopy, and Fourier transform infrared spectroscopy. The nanocomposite was successfully applied to extract of the polycyclic aromatic hydrocarbons (PAHs) from water samples. Compared to Fe3O4/PPy, the Fe3O4/CNS/PPy nanocomposite exhibits improved properties in terms of extraction. The amount of adsorbent, salt effect, extraction time, desorption time, type, and the volume of desorption solvent were optimized. Following the desorption of the extracted analytes, the PAHs (i.e., naphthalene, 2-methylnaphthalene, 2-bromonaphthalene, fluorene, and anthracene) were quantified by gas chromatography–flame ionization detector. The PAHs can be determined in 0.05–100.00 ng mL−1 concentration range, with limits of detection (at an S/N ratio of 3) ranging from 0.01 to 0.05 ng mL−1. The repeatability of the method was investigated with relative standard deviations of lower than 9.9% (n = 5). Also, the recoveries from spiked real water samples were in the range of 88.9–99.0%. The results indicate that the novel material can be successfully applied for the extraction and analysis of PAHs from water samples.

We synthesized Co 0.25 Cu 0.25 Mn 0.5 Fe 2 O 4 @CMC (CCMFe 2 O 4 @CMC) nanorods as a new dual-modal simultaneous for magnetic resonance imaging contrast agent and nanocarrier for drug delivery system. Impact of CCMFe 2 O 4 @CMC nanorods were investigated on the longitudinal (T1), transverse (T2) and transverse (T2 ∗ ) relaxation times for in vitro MRI contrast agent in water and also for drug delivery system, l -dopa was coated on CCMFe 2 O 4 @CMC nanorods and then in vitro drug release test was carried out at three PHs values and different temperatures. In vitro MR imaging demonstrated that r 2 value of CCMFe 2 O 4 @CMC nanorods is 138.33 mM −1 s −1 , CCMFe 2 O 4 @CMC is useful as T2 contrast agent relative to other T2 contrast agants. In vitro drug release test shows the amount of released l -dopa from CCMFe 2 O 4 @CMC nanorods at medium with pH = 1.2 is more than pH = 5.3 and 7.4.

This study identified concentrations, molecular distributions, toxicities, and sources of polycylic aromatic hydrocarbons (PAHs) in street dust from different land use of Bushehr city in southwest ...

l-Proline has been used as an efficient, reusable, and bifunctional organocatalyst for the one-pot, two-step, five-component synthesis of novel 1,4-dihydrobenzo[a]pyrido[2,3-c]phenazines by the condensation reaction of 2-hydroxynaphthalene-1,4-dione, aromatic 1,2-diamines, aldehydes, ammonium acetate, and ethyl acetoacetate under conventional heating in solvent-free conditions. In this domino transformation, six bonds and two new rings are efficiently formed. High yields, short reaction time (20–30 min), operational simplicity, easy work-up procedure, avoidance of hazardous or toxic catalysts and organic solvents are the main advantages of this green methodology.

Coastal areas are critical parts of the Persian Gulf with regard to high populations and economically driven activity. They pose major concerns because of the presence of toxic chemicals, and hence harmful effects on marine ecosystems. In this study, 14, 15 and 12 coastal sediment samples were collected in Bushehr province and analyzed, respectively, for potentially toxic elements (PTEs), polycyclic aromatic hydrocarbons (PAHs) and microplastics (MPs). The results showed that almost all PTEs were not significantly enriched. Most elements exhibited their highest levels at stations close to urban areas and along the pathway of ships and boats. Based on enrichment factor and statistical evaluations, two main sources of trace elements were identified: anthropogenic (Mo, Cu, Pb, As and Sb) and geogenic (Zn, Ni, Co, Mn, Fe, Cd, Cr and Al). Regarding MPs, a total of 577 pieces were observed with sizes ranging between 500 and 1000 µm. The dominant shape of the MPs was fibrous with the dominant colors being white and black. The concentration of total PAHs were fairly low in the sediments, with their source determined to be pyrogenic in origin.

The persistence of microplastics (MPs) in the environment is seen as a global hazard. Typically, polycyclic aromatic hydrocarbons (PAHs) and MPs are classified into two separate pollutant groups and the relationships between the two stressors are poorly understood. Wheat is the most important grain in the human food chain. Thus, investigating adsorption and desorption capacity of polyethylene terephthalate (PET), when exposed to PAHs in irrigation water and wheat rhizosphere zone is very important. Adsorption experiments based on Langmuir or Freundlich models were performed to specify the adsorption capacity of PET particles for Naphthalene and Phenanthrene. Besides, desorption experiments were conducted to determine whether MPs in the rhizosphere zone could release previously sorbed Naphthalene and Phenanthrene. For desorption experiments, three scenarios were considered according to different environmental stresses. The results show that, when PET particles were exposed to Naphthalene (18 μ g/l) and Phenanthrene (0.11 μ g/l), they adsorbed 17.44 and 0.03 μ g/l of Naphthalene and Phenanthrene, respectively. PET particles also desorbed the same concentration in all three scenarios (root exudates) for Naphthalene (on average 3.775 μ g/l) and Phenanthrene (on average 0.00875 μ g/l). This indicates that the change in root exudates content does not affect the desorption capacity of PET for PAHs contaminants. Generally, the results of this study, suggest that PET particles absorbed 96.89% of Naphthalene and 27.27% of Phenanthrene and desorbed 21.65% of adsorbed Naphthalene and 29.17% of adsorbed Phenanthrene in the root exudate. The results show that PET particles can act as a carrier and transport PAHs from any source to the rhizosphere zone.

Exposure of microplastics (MPs) to a cohort of adults of various demographics from different regions of Iran has been quantitatively assessed. Specifically, MPs were retrieved from filtered washes of the hand and face skin, head hair and saliva of individuals (n = 2000) after an exposure period of 24 h and were counted and, in a selected number of cases, characterised for shape-form and size microscopically. A total of over 16,000 MPs were recorded in the study, with head hair returning the most samples (> 7000, or, on average, >3.5 MPs per individual per day), saliva returning the least samples (about 650, or on average 0.33 MPs per individual), and MPs about twice as high in males than females. The number of MPs was similar amongst residents of different urbanised regions, albeit with evidence of greater quantities captured in more humid settings, and was considerably lower in residents of a remote and sparsely populated area. Polyethylene-polyethylene terephthalate and polypropylene fibres of < 100 μm in length, likely derived from clothing and soft furnishings in the indoor setting and a wider range of sources in the exterior environment, were the most abundant type of MP in all body receptors. Daily sampling of receptors from six participants over a seven-day period revealed that, despite these broad trends, both inter- and intra-individual exposure was highly heterogeneous. Although the present study has demonstrated the ubiquity of MP exposure, the resulting impacts on human health are unknown.

While the distribution and effects of microplastics (MPs) have been extensively studied in aquatic systems, there exits little information on their occurrence in the terrestrial environment and their potential impacts on human health. In the present study, street dust and suspended dust were collected from the city and county of Asaluyeh, Iran. Samples were characterized by various microscopic techniques (fluorescence, polarized light, SEM) in order to quantify and classify MPs and microrubbers (MRs) in the urban and industrial environments that are potentially ingestible or inhalable by humans. In

Street dust samples from Asaluyeh County were collected in summer season for analysis of PTEs and mineralogy. For this purpose, 43 street dust samples were collected from industrial and urban areas. Also, three soil background samples were collected from 40 cm depth. Calculated enrichment factors revealed high enrichment of Sb, Mo, Zn, Pb, Cu and Hg. Generalized estimating equations (GEE) and positive matrix factorization (PMF) models are used as a robust statistical method. GEE, PMF, Mann–Whithney, and PCA statistical analyses revealed two main sources of trace elements as road traffic and industrial emissions (Sb, Mo, Cu, Pb, Zn, Ni, Co, As and Cd) and re-suspended soil particles (Al, Cr, Ti, Sc, Mn and Fe). BCR sequential extraction results and interpolation maps indicated higher Mo, Cu, Fe, Cr, Zn, Sb, Co and Cd concentration in industrial regions and higher Mn, Ni, Cu, Pb, Hg, and As in urban areas. Measured physicochemical parameters showed that traffic load and velocity of vehicles have direct effect on the texture of street dust. Also Eh–pH diagrams revealed dominant species of Pb and Zn (S–O–H system), Cu and Sb (S–C–O–H system) in runoff as Zn2+, ZnCO3, ZnO, ZnO22−, CuO, Cu2O, Sb2O4, PbCO3, and PbO. Finally, calculated human health risk using mobile phase of elements indicated that HI for the studied elements were lower than the safe level of 1, revealing little adverse health risks from street dust exposure. Scanning electron microscope (SEM) result indicated some nanometer-size particles which can be very dangerous to human health.

The geochemical nature and health hazards of potentially toxic elements (PTEs) and polycyclic aromatic hydrocarbons (PAHs) in the street dust of Bandar Abbas, Iran, are investigated in this study based on 27 street dust samples. Mean concentrations of Cu, Pb, Zn, As, Sb, and Hg revealed elevated concentrations as compared to the world soil average. Calculated enrichment factors (EFs) indicated that there is very high contamination in dust particles owing to anthropogenic emissions. Two main sources of PTEs are traffic emissions (Cu, Pb, Zn, Co, Mn, Fe, As, Cd, Sb, and Hg) and resuspended soil particles (Al, Ti, Ni, and Cr). Statistical analysis shows that Al, Mn, Ni, Ti, Cr, Fe, and Co are geogenic, whereas PAHs are mainly derived from traffic emissions. Values of incremental lifetime cancer risk (ILCR), as derived from a modified model of the United State Environmental Protection Agency (USEPA), indicate that Bandar Abbas residents are potentially exposed to high cancer risk, especially via dust ingestion and dermal contact, whereas the level of hazard index (HI), hazard quotients (HQ), and cancer risk associated with exposure to the elements in street dust fall lower than threshold values representative of health risks.

This study aimed to (1) investigate microrubbers (MRs) for the first time and identify microplastics (MPs) in street dust, (2) determine the physicochemical and mineralogical characteristics and morphology of dust particles, (3) understand the concentration and the possible source(s) of heavy metals/metalloids, (4) identify the chemical speciation and mobility potential of trace metals in urban street dusts, and (5) determine adverse health effects of street dust on children and adults living in the city of Bushehr in southwestern Iran. Generally, twenty four street dust samples were collected and analyzed. Calculated enrichment factors indicate high levels of contamination. Statistical analysis reveals that the two main sources of trace elements include road traffic emissions (Cu, Zn, Sb, Hg, Pb, Mo) and re-suspended soil particles (Al, Mn, Ni, Ti, Cd, Co). BCR sequential extraction results indicated that As, Zn, Cu, and Pb mainly occur in the exchangeable fraction and hence are highly bioavailable. X-ray powder diffraction analysis revealed the presence of calcite, dolomite, quartz, and magnetite. The size distribution of dust particles was also investigated using a scanning electron microscope (SEM), while elemental distribution was analyzed using an attached energy dispersive X-ray spectrometer (SEM–EDS) unit. Dust particles from heavy traffic areas are much finer compared with other investigated areas. MPs and MRs, mostly fibers and fragments, were detected in all samples [ranging from 210 to 1658 (MPs) and 44 to 782 (MRs) items/10 g dust] using fluorescence microscopy. The hazard index for As is higher than 10−4 for children and adults indicative of high risk. According to the calculated potential ecological risk index, Hg indicated moderate ecological risk in the street dust of the study area.

Superparamagnetic γ-Fe2O3@SiO2@lisinopril (MNPs-Lisinopril) nanoparticles are T2 and T2* negative contrast agents for magnetic resonance imaging. In this work, we report the preparation of lisinopril-coated MNPs for the first time as new T2 and T2* negative contrast agent for in vitro and in vivo MRI imaging and demonstrate the potential it simultaneously for drug delivery system, diagnose the tumors and MRI contrast agent. Measurements on the relaxivities (r1, r2 and r2*) of the MNPs-Lisinopril were determined in deionized water (in vitro). Furthermore, after subcutaneous injection of the MNPs-Lisinopril into 4T1 (ATCC® CRL2539™) tumor in BALB/c mice, the relaxivities were determined by a 1.5 T MRI apparatus (in vivo). T2- and T2*-weighted MRI images of MNPs-Lisinopril showed that the MR signal intensity decreased significantly with increasing nanoparticle concentration in water. With measured r2 values up to 236.66 mM−1s −1, our MNPs-Lisinopril show better performance than commercial alternatives. Also we tested drug release of Lisinopril coated MNPs at two different pHs. The MNPs- Lisinopril is a pH-sensitive drug delivery system and releases different amounts of lisinopril from MNPs-Captopril in different pHs.

BACKGROUND: The objectives of this study were optimization of silver nanoparticle synthesis using biotransformations by Lactobacillus casei subsp. casei, and studying the location of nanoparticles synthesis in this microorganism. RESULTS: The presence of AgNO3 (0.1 mmol L−1) in the culture as the enzyme inducer, and glucose (56 mmol L−1) as the electron donor in the reaction mixture had positive effects on nanoparticle production. By gradually increasing the concentration of AgNO3 (as the substrate) to 6 mmol L−1, nanoparticle production was increased. By increasing biomass, nanoparticles production was also increased. Biosynthesized silver nanoparticles were almost spherical, single (25–50 nm) or in aggregates (100 nm), attached to the surface of biomass or were inside and outside of the cells. CONCLUSION: The present study demonstrated the bioreductive synthesis of silver nanoparticles using L. casei subsp. casei at room temperature. In this research, and due to experience in optimization of biotransformation reactions, the reaction conditions were successfully optimized to increase the yield of nanoparticles production and productivity of this biosynthetic approach. Copyright © 2012 Society of Chemical Industry

Recent developments in the biosynthesis of nanomaterials have demonstrated the important role of biological systems and microorganisms in nanoscience and nanotechnology. These organisms show a unique potential in environmentally friendly production and accumulation of nanoparticles with different shapes and sizes. Therefore, researchers in the field of nanoparticle synthesis are focusing their attention to biological systems. In order to obtain different applied chemical compositions, controlled monodispersity, desired morphologies (e.g., amorphous, spherical, needles, crystalline, triangular, and hexagonal), and interested particle size, they have investigated the biological mechanism and enzymatic process of nanoparticle production. In this review, most of these organisms used in nanoparticle synthesis are shown.

The reaction between squaric acid with one equivalent of alkyl isocyanides such as t-butyl isocyanide, cyclohexyl isocyanide and n-butyl isocyanide in ethanol at room temperature after 3h afforded the corresponding squaramic acid derivatives. Symmetric 2,4-squaryl diamides were obtained when the reaction of squaric acid was carried out with two equivalents of alkyl isocyanides under the same conditions. Asymmetric 2,4-squaryl diamides were obtained by reaction of squaramic acids with one equivalent of alkyl isocyanides.

Feeder reconfiguration (FR) is an operational process that modifies feeder topology structure by changing section as well as tie switches status. The main objective of FR is to find a radial operating configuration that optimizes certain objectives while satisfying operational constraints. Increased number of switches led to a better reconfiguration but at the same time increases investment cost as well as outage time. Hence, optimal composition and placement of switches is required. Mostly feeder reconfiguration problem is formulated as a multi-objective dynamic mixed integer non linear programming problem. The objective functions are cost reduction (investment and operational), loss minimization, improved reliability and voltage profile improvement. In the era of deregulation, distributed generators (DGs) are being employed widely due to certain benefits. Therefore, in this paper different FR techniques with and without DGs have been investigated.

Silver nanoparticles are increasingly used in various fields of biotechnology and applications in the medicine. Objectives of this study were optimization of production of silver nanoparticles using biotransformations by Fusarium oxysporum, and a further study on the location of nanoparticles synthesis in this microorganism. The reaction mixture contained the following ingredients (final concentrations): AgNO3 (1-10 mM) as the biotransformation substrate, biomass as the biocatalyst, glucose (560 mM) as the electron donor, and phosphate buffer (pH= 7, 100 mM). The samples were taken from the reaction mixtures at different times, and the absorbance (430 nm) of the colloidal suspensions of silver nanoparticles hydrosols was read freshly (without freezing) and immediately after dilution (1:40). SEM and TEM analyses were performed on selected samples. The presence of AgNO3 (0.1 mM) in the culture as enzyme inducer, and glucose (560 mM) as electron donor had positive effects on nanoparticle production. In SEM micrographs, silver nanoparticles were almost spherical, single (25-50 nm) or in aggregates (100 nm), attached to the surface of biomass. The reaction mixture was successfully optimized to increase the yield of silver nanoparticles production. More details of the location of nanoparticles production by this fungus were revealed, which support the hypothesis that silver nanoparticles are synthesized intracellularly and not extracellularly.

To evaluate CD10 expression in urothelial carcinoma of the urinary bladder and the association of immunohistochemical (IHC) CD10 expression intensity with grade and stage.Descriptive cross-sectional analytical study.Armed Forces Institute of Pathology, Rawalpindi, from January to December 2011.Fifty consecutive cases of urothelial bladder carcinomas, obtained through transurethral resections, were included in this study. Hematoxylin-eosin (HE) stained sections from each case were re-evaluated histopathologically according to WHO 2004 grading system. The TNM system was used for pathologic staging. On selected slides IHC CD10 marker was applied and a semiquantitative scoring for its expression based on the percentage of positive cells and intensity was performed. Data was entered and analysed on SPSS version 17. Fisher's exact test was used to compare grades, stages of urothelial carcinoma with CD 10 expression and age groups. P0.05 was taken as level of significance.Urothelial carcinoma was more common in males. The male to female ratio was 9:1. The older patients50 years had higher grade and stage as compared to the younger patients. All cases of high grade urothelial carcinoma showed higher positivity for CD 10. Twenty cases (86.95%) of high grade urothelial carcinoma were positive with +2 immunostaining while 3 cases (13.04 %) were positive with +1 staining. None of the tumors of stage pTa was positive for CD 10 expression. Of all patients with stage pT 1 tumor, 1 case (5.3%) was CD 10 negative and 17 cases (89.9%) were CD 10 positive having +1 staining with 5 - 50% staining and 1 case (5.3%) had +2 staining with more then 50% expression. Out of all patients with stage pT 2, no tumor was CD 10 negative, 3 (13.6%) patients were CD 10 positive with +1 staining and 19 (86.4%) with stage pT 2 tumor had stained positive with +2 staining.CD 10 expression was greater in high grade and invasive urothelial carcinomas; it may be associated with tumor progression in bladder cancer pathogenesis.

Regarding the importance of starvation and refeeding and the occurrence of refeeding syndrome in various conditions, the present study was conducted to investigate the effects of refeeding on some parameters of energy metabolism and electrolytes and changes of hepatic tissue in male Wistar rats. Fifty-seven rats were divided into six groups, having 6 to 11 rats. Food was provided ad-libitum until three months and then the first group was considered without starvation (day 0). Other rats were fasted for two weeks. Group 2 was applied to a group immediately after starvation (day 14). Groups 3 to 6 were refed in days 16 till 22, respectively. At the end of each period, blood and tissue samples were taken and histopathological and serum analysis, including serum electrolytes (calcium, phosphorus, sodium, potassium), the energy parameters (glucose, insulin, cortisol) and the liver enzymes (ALT, AST, ALP) were determined. Insulin decreased by starvation and then showed an increasing trend compared to starvation period, which the highest amount of this parameter was observed eight days post-refeeding. Serum glucose level showed the opposite pattern of insulin. Histopathological examination of the tissue sections revealed clear vacuoles after starvation and refeeding, in which the severity of lesions gradually decreased during refeeding. The cortisol level decreased by starvation and then increased during refeeding. Also, potassium and phosphorus concentrations declined by refeeding and the serum sodium and potassium levels were changed in the relatively opposite manner. The calcium level decreased by starvation and then increased during refeeding. These results could help recognize and remedy the refeeding syndrome.