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This study reports the synthesis and characterization of a Fe2O3-PANI/CdS nanocomposite for the photocatalytic degradation of Malachite Green dye under visible light irradiation. The successful formation of the synthesized nanocomposite was confirmed through various characterization techniques, including Fourier-transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), Transmission Electron Microscopy (TEM), and energy-dispersive X-ray spectroscopy (EDS). Under optimized conditions, the Fe2O3-PANI/CdS nanocomposite demonstrated excellent photocatalytic performance, achieving a degradation efficiency of 95.7% for Malachite Green dye within 30 min. Kinetic studies revealed that the degradation process followed a pseudo-first-order reaction model. Furthermore, the nanocomposite exhibited good reusability, maintaining high degradation efficiency after five consecutive reuse cycles. These results demonstrate the potential of the Fe2O3-PANI/CdS nanocomposite as a promising photocatalyst for wastewater treatment applications. [ABSTRACT FROM AUTHOR]

A magnetic mesoporous silica, Fe3O4@SiO2@KCC-1 (MMS), was prepared using a hydrothermal method and subsequently modified by post-grafting to synthesize Fe3O4@SiO2@KCC-1-SH (MMS-SH). The synthesized mesoporous materials were characterized using various techniques, including X-ray diffraction (XRD), vibrating sample magnetometry (VSM), field emission scanning electron microscopy (FE-SEM), X-ray energy diffraction spectroscopy (EDS) analysis and mapping, nitrogen adsorption/desorption measurement, Thermal gravimetric analysis (TGA) and Fourier transform infrared (FT-IR) spectroscopy. Their removal capacity for heavy metal ions was determined with flame atomic absorption spectroscopy (AAS). Due to their large surface area, these adsorbents were used for the removal of Cu(II), Ni(II), Cd(II), Hg(II), and Pb(II) ions. The unmodified MMS exhibited removal capacities of 24.10, 28.54, 21.71, 32.5, and 30.06 mg/g for Cu(II), Ni(II), Cd(II), Hg(II), and Pb(II) ions, respectively. The removal of heavy metal ions by MMS followed a pseudo-first-order kinetic model and fit well with the Langmuir model. However, modifying the surface of the MMS with thiol groups significantly increased the removal capacity for all mentioned metal ions to 36.21, 32.83, 27.34, 48.75, and 41.40 mg/g, respectively. The removal of heavy metal ions by MMS-SH followed a pseudo-second-order kinetic model and fit well with the Temkin model. The antibacterial assays showed that the synthesized mesoporous materials were generally more effective against both planktonic Escherichia coli (gram-negative bacterium) and its ability to form biofilm compared to Staphylococcus aureus (gram-positive bacterium). [ABSTRACT FROM AUTHOR]

This study investigates the development of magnetic mesoporous silica functionalized with amine groups (MMS-NH2) for its combined capability in heavy metal removal and bacterial inhibition, aiming to address critical water treatment challenges. MMS-NH2 was successfully synthesized and meticulously characterized using various techniques: Field Emission Scanning Electron Microscopy (FESEM) for morphology, Brunauer-Emmett-Teller (BET) analysis for surface area and porosity, X-ray diffraction (XRD) for crystallinity, Fourier Transform Infrared (FTIR) spectroscopy for functional group identification, Thermogravimetric Analysis (TGA) for thermal stability, and Vibrating Sample Magnetometry (VSM) for magnetic properties. The removal efficiency of five common heavy metals (Pb(II), Cu(II), Ni(II), Hg(II), and Cd(II)) from water using MMS-NH2 was investigated. influence of adsorbent dosage (0.05–2 g.L− 1), solution pH (2–10), and initial metal ion concentration (50–200 mg.L− 1) on the adsorption process was systematically investigated, revealing optimal conditions for each metal ion. Isotherm models (Langmuir, Freundlich, Dubinin-Radushkevich) were employed to understand the adsorption mechanism, indicating a favorable and monolayer chemisorption process. Kinetic models (pseudo-first-order, pseudo-second-order, Elovich) were used to study the adsorption kinetics, suggesting a rapid and chemisorption-controlled mechanism. Thermodynamic parameters (ΔG°, ΔH°, and ΔS°) were calculated, confirming the spontaneous and exothermic nature of the adsorption process. Furthermore, the antibacterial activity of MMS-NH2 was investigated against both Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus aureus) bacteria. The results demonstrated significant inhibition rates, ranging from 70 to 90%, for both bacterial strains. The amine group functionalization is attributed to enhancing both heavy metal adsorption capacity and bacterial inhibition. [ABSTRACT FROM AUTHOR]

A new mixed-ligand oxidovanadium (IV) complex, [VO(DFX)(1,10-phen)], in which DFX = Deferasirox and 1,10-phen = 1,10-phenanthroline, was synthesized using the reflux method and characterized by Fourier transform infrared spectroscopy (FT-IR), UV–Vis spectroscopy and field emission scanning electron microscopy (FE-SEM). Distorted octahedral geometry is suggested for the complex. The DFX ligand is coordinated to the central atom by two phenolate oxygen atoms and one triazole nitrogen atom. Two nitrogen atoms of the 1,10-phen ligand and the oxo group occupy three other positions around the central atom. The in vitro antibacterial activity of the synthesized complex, metal precursor (VO(acac)2) and parent ligands was evaluated against Staphylococcus aureus, Bacillus cereus, Escherichia coli, and Pseudomonas aeruginosa bacterial strains. Furthermore, the antibiofilm activity of these compounds was investigated against S. aureus and P. aeruginosa bacteria. Based on the obtained results, the [VO(DFX)(1,10-phen)] complex exhibited higher antibacterial and antibiofilm activities in comparison to VO(acac)2, DFX and 1,10-phen. [ABSTRACT FROM AUTHOR]

In recent years, green corrosion inhibitors derived from natural plant resources have garnered much interest. In the present work, at first, we investigated the corrosion behavior of mild steel (st-37) in the presence, and absence of Dracocephalum extract based on bulk size as a corrosion inhibitor in two widely used acidic environments (0.5 M H2SO4, and 1.0 M HCl), at room temperature. Then, we used Dracocephalum extract based on nanometer size to reduce the optimal concentration of inhibitor, increase the corrosion resistant, and efficiency. Dracocephalum extract does not contain heavy metals or other toxic compounds, and also good characteristics such as low cost, eco-friendly, and widespread availability, make it suitable nature candidate as an environmentally safe green inhibitor. The anticorrosive behavior was assessed using electrochemical impedance spectroscopy (EIS), and potentiodynamic polarization (PP). In all of the studies, the inhibitory efficiency (IE%) increased as the extract dose was increased. But by using nano extract, in addition to maintaining high efficiency, the amount of inhibitor was reduced significantly. The highest IE% is 94% at the best dose of nano extract (75 ppm), but the highest IE% is 89% at the best dose of the bulk extract (200 ppm) in H2SO4 solution. Also, for the HCl solution, the highest IE% is 88% at the best dose of nano extract (100 ppm), but the highest IE% is 90% at the best dose of the bulk extract (400 ppm), by polarization method. The PP results suggest that this compound has an effect on both anodic, and cathodic processes, and that it adsorbs on mild steel surface according to the Langmuir adsorption isotherm. Optical microscopy, scanning electron microscopy (SEM) analysis, and a solid UV–Visible reflection spectrum were used to investigate the alloys' surface morphology. [ABSTRACT FROM AUTHOR]

Herein, at first, green SnO2@ZnO nanocomposites were synthesized using Calotropis plant extract as an electron transfer material (ETM) to fabricate low-temperature-processed perovskite solar cells (PSCs). Then, the polyaniline (PANI) polymer was applied as an efficient additive to improve perovskite film quality. Under the effects of the small content of PANI additive, the quality of perovskite films is enhanced, which showed higher crystallinity in (110) crystal plane; also, the perovskite grains were found to be enlarged from 342 to 588 nm. The power conversion efficiency (PCE) of the prepared PSCs with SnO2@ZnO.PANI nanocomposites electron transfer layer (ETL) increased by 3.12%, compared with the PCE of SnO2@ZnO nanocomposites. The perovskite devices using SnO2@ZnO.PANI nanocomposites ETL have shown good stability during 480 h of tests. Furthermore, the optimal PSCs were fabricated by the mp-TiO2/SnO2@ZnO.PANI nanocomposites as ETL, which has a power conversion efficiency of 15.45%. We expect that these results will boost the development of low-temperature ETL, which is essential for the commercializing of high-performance, stable, and flexible perovskite solar cells. [ABSTRACT FROM AUTHOR]

Boron nitride nanotubes (BNNTs) are of intense scientific interest due to their unrivaled physicochemical characteristics, extraordinary thermal, electronic, mechanical, optical properties, and prospective applications in various nanotechnologies. Therefore, they are particular candidates for the development of new materials potentially applied in abundant applications. However, obtaining homogenous composite materials requires a good dispersion of BNNTs, as well in solvents or in the matrix, which still has remained challenging. The preparation of effective dispersions of BNNTs presents a major impediment to the extension and utilization of BNNTs. BNNTs intrinsically tend to bundle and/or aggregate. The prevention of such behavior has been explored by testing various techniques to improve the dispersibility of BNNTs in a variety of solvents. There are mainly two approaches to obtain a good quality dispersion; chemical functionalization and physical interactions. The chemical functionalization technique has been found effective, but deteriorates the intrinsic properties of BNNTs through the introduction of defects on the wall. Physical blending approaches with the ultrasound and high-speed shearing have been proven capable of debundling BNNTs and stabilizing individual BNNTs while maintaining their integrity and intrinsic properties. Attention has been brought to the study of the dispersion of BNNTs in aqueous media and most attention is paid to molecular dynamics (MD) simulation techniques and other physical techniques, as well as to the use of various surfactants and polymers. [ABSTRACT FROM AUTHOR]

The Moon and Mercury are airless bodies, thus they are directly exposed to the ambient plasma (ions and electrons), to photons mostly from the Sun from infrared range all the way to X-rays, and to meteoroid fluxes. Direct exposure to these exogenic sources has important consequences for the formation and evolution of planetary surfaces, including altering their chemical makeup and optical properties, and generating neutral gas exosphere. The formation of a thin atmosphere, more specifically a surface bound exosphere, the relevant physical processes for the particle release, particle loss, and the drivers behind these processes are discussed in this review. [ABSTRACT FROM AUTHOR]

Deformation behavior of a rolled Mg–Y–Nd–Gd magnesium alloy was studied at a temperature range of 240–480 °C under plane strain compression. Two types of samples including different loading-constraining configurations were employed to study anisotropy in deformation response. The result showed that plane strain deformation mode extends the temperature range for predominance of twinning up to 480 °C. However, yield anisotropy was diminished by increasing temperature to 480 °C. Moreover, plane strain deformation mode caused the development of dynamic recrystallization to be postponed to high strains. Deformation behavior of the two sample types were explained by calculation of Schmid factor and texture analysis. Fine dynamically recrystallized grains were traced to form at 420 and 480 °C. Relying on EBSD analysis, the development of new grains was explained using continuous dynamic recrystallization mechanism, where pyramidal and prismatic poles of new grains were rotated relative to their parent grain. The dynamic evolution of metastable β′ and β″ phases was also observed at high temperatures, the fraction of which was remarkably increased with increasing temperature to 420 and 480 °C. [ABSTRACT FROM AUTHOR]

The dendrimer has a high degree of geometric symmetry, a precise and controllable molecular size, a large number of surface-active functional groups, a rich cavity inside the molecule, and a controlled molecular chain growth. The unique structural properties of the above-mentioned macromolecules have made it a research hot spot in many fields. Molecular simulation technology, as a new scientific research method, plays an important role in the basic theory and applied research of dendrimers. This paper reviews the basic progress of molecular simulation technology in the field of dendrimers in recent years, including the application of dendrimers in medicine, DNA, pharmaceutical carriers, proteins, amino acids, and so on. [ABSTRACT FROM AUTHOR]

The investigation of porous graphene, especially experimental research, is a challenging issue in related academic and technology and has become a hot topic in recent years. It is well known that the preparation of porous graphene is a difficult problem in experimental techniques. To prepare nanoporous graphene, much attention must focus on the quality of nanoporous structures and throughput array pores. Therefore, a comprehensive summary as much as possible has been made to provide a better understanding of the progress. A summary of synthesis techniques, the properties of nanoporous graphene membranes from the synthesis point of view, and potential applications of porous graphene and graphene oxide for gas separation on the basis of theoretical studies were given attention in this paper. Gas separation, including carbon dioxide capture, gas storage, natural gas sweetening, and flue gas purification through porous graphene, is of great interest. Porous graphene with narrow pore distribution provides exciting opportunities in gas separation processes. [ABSTRACT FROM AUTHOR]

The community composition of benthic macrofauna and relationships between physiochemical parameters of the water and sediment texture were assessed in Hara Biosphere Reserve, Northern Persian Gulf. The spatial distribution and diversity of macrobenthos were sampled within three distinctive mangrove zones (deltaic, island and coastal) during two sampling seasons between August 2014 and January 2015. A total of nine transects perpendicular to the coastline were selected to cover over the entire study area. The counts of all macrofauna were recorded from each zone and station with three replicate sediment samples. The snails, Cerithidea cingulata and Asseminea sp., were observed throughout three mangrove zones, but their abundance varied among habitats. The bivalve Dosinia ceylonica found to be more abundant in delta, whereas burrowing crabs Ocypode and Uca were dominate in coastal zone. Terebralia palustris and amphipods were recorded frequently in island zone. The nonmetric multidimensional scaling ordinations and a three-way factor PERMANOVA indicated that macro-invertebrate species composition significantly differed among different mangrove zones. The results also showed the seasonal variations. The findings of diversity indices illustrated that deltaic zone had the highest abundance and diversity, while the coastal zone showed the lowest values among the three zones. Taken together, the observations demonstrated that the different hydrological conditions, temperature, salinity and sediment texture were the main factors determining dispersion of benthic faunal assemblages among different mangrove habitats at Hara Biosphere Reserve. There is a need to consider such variables in ecological studies to understand differences of macrofaunal diversities in these complex habitats. [ABSTRACT FROM AUTHOR]

Recently, there has been increased interest in the use of representative areas as tools for the conservation of marine habitats and species. This has resulted in the declaration of many coastal–marine protected areas around the world. The criteria for the establishment of these areas have been suggested by different authors and international bodies, and for each region or country, that has to be done according to its characteristics, conditions and facilities. In this study, the already established criteria were revised based on new views and approaches at the international levels and the background experiences in the country. This revision was made by using expert choice approach and analytical hierarchy process method. In this regard, a hierarchy tree was made and scored for all physical features and habitats and upon the results, six criteria were selected compared to already established 15 criteria. These were then used with the same method to choose the subcriteria for the Hormozgan province and to map these resources. Altogether, 31 subcriteria were recognized, and then, total score for each area was calculated and encoded into five conservation groups which mapped alongside the coastline and the marine parts. These criteria and subcriteria established in this way are flexible and subject against any changes whenever it is necessary in the future. The result of this study could be applied for other regions of the country and could act for the selection of coastal–marine protected areas. [ABSTRACT FROM AUTHOR]

An ultrafine/nano-grained AZ31 magnesium alloy was processed through multipass accumulative back extrusion at 280 and 380 °C. Texture analysis was conducted to determine preferred crystallographic orientations developed during multipass deformation. The anisotropy in mechanical properties of the processed materials was studied by compressive and tensile testing. The results implied that the accumulative back extrusion effectively reduces the anisotropy of yield strength, ultimate strength and strain-to-fracture during compressive and tensile loading. The operations of different twinning/slip systems during compressive and tensile deformation were discussed using Schmid factors measurements. A decrease in twinning-related anisotropy, as well as the contribution of different slip systems in strain accommodation, could reduce the mechanical anisotropy of ultrafine/nano-grained AZ31 alloy. The compressive strength of the two-pass processed material was lower along extrusion direction than transverse direction; however, the result was reverse after four passes. The tensile behavior implied that the contribution of basal slip might accommodate strain along length as well as the thickness of the specimen, while prismatic slip may assist in narrowing the width of the specimen and elongating the length. [ABSTRACT FROM AUTHOR]

Hot compression tests of a new high-Mn austenitic steel were carried out at deformation temperatures of 700, 800, 900, and 1000 °C under strain rate of 0.01 s−1. The hot deformation behavior was investigated by the analyses of flow curves, texture, and deformed microstructures. Microstructures of the deformed specimens and macrotexture were examined using electron backscatter diffraction and x-ray diffraction methods, respectively. The results showed that the flow stress depended strongly on the deformation temperature and decreased by increasing deformation temperature. The microstructural evidence indicated that the dynamic recrystallization (DRX) process of experimental steel was initiated at 800 °C with necklace structure. The volume fraction of DRX grains was considerably increased by increasing deformation temperature to 1000 °C. Texture of the DRX grains tended to become a weak texture and was associated with the formation of Goss and R-Cube components. Meanwhile, martensitic transformation was detected in the hot-deformed austenite. The martensitic transformation was the most difficult in the DRX grains because of the effect of small grain size. The tendency of transformation was decreased after compression at 1000 °C. [ABSTRACT FROM AUTHOR]

An AZ31 wrought magnesium alloy was processed by employing multipass accumulative back extrusion process. The obtained microstructure, texture, and room temperature tensile properties were characterized and discussed. Ultrafine-grained microstructure including nano-grains were developed, where the obtained mean grain size was decreased from 8 to 0.5 μm by applying consecutive passes. The frequency of both low angle and high angle boundaries increased after processing. Strength of the experimental alloy was decreased after processing, which was attributed to the obtained texture involving the major component lying inclined to the deformation axis. Both the uniform and post-uniform elongations of the processed materials were increased after processing, where a total elongation of 68 pct was obtained after six-pass deformation. The contribution of different twinning and slip mechanisms was described by calculating corresponding Schmid factors. The operation of prismatic slip was considered as the major deformation contributor. The significant increase in post-uniform deformation of the processed material was discussed relying on the occurrence of grain boundary sliding associated with the operation of prismatic slip. [ABSTRACT FROM AUTHOR]

Nanotubes have extraordinary properties, which have attracted the attention of many researchers from diverse fields. The interaction between carbon nanotube (CNT) or boron nitride nanotube (BNNT) and polymer/copolymer/surfactant has shown potential improvement in properties and performance. This paper reviews the recent studies in this field obtained from molecular dynamics simulation calculations, focusing on the interaction energies between nanostructure and polymer, radial distribution function, diffusion and radius of gyration and some other physical chemistry properties. Recent studies show that the intermolecular interaction in mentioned systems is strongly influenced by the specific monomer structure of polymers. The high values of intermolecular interaction energy of such composites offer that an efficient load transfer exists at the interface between nanotube and polymer, which is of a key role in the composite reinforcement practical applications. Our study reviewed the possibility of wrapping CNT/BNNT/CNT bundles by polymers and also the effects of CNTs/CNT bundles' length on the conformational behavior of polymer adsorbed on these nanostructures. [ABSTRACT FROM AUTHOR]

Separating molecular species is an important precursor for various applications. In this work, we have utilized molecular dynamics (MD) simulations to examine how pore radius and structure affect the separation process. We show from MD simulations that 2-D graphene sheets with designed sub-nanometer pores can efficiently separate the Kr-85 radionuclide gas from an N/O mixture. Three species of gases (Kr-85, N and O were considered in the simulation box in which different sizes and geometries of pores were modeled on the graphene sheet. The ( $ 30\times 30\times 80$ Å^3 simulation box contains a nanoporous graphene membrane in the middle of the box and two fixed walls with equal distances on both sides of the nanoporous graphene. The results revealed that Kr-85 separation was improved by using an optimized pore structure. It was also found that the Kr-85 gas radionuclides could be completely separated from nitrogen and oxygen molecules in the pore-7 configuration. Restriction of the molecular orientation largely prohibited the permeation of nitrogen molecules. It was also found that nitrogen was more strongly adsorbed onto the membrane than oxygen, while krypton was not adsorbed. [ABSTRACT FROM AUTHOR]

Water and air pollutants have huge impacts on the entire living system. In addition, the newly emerging nanopollutants, increasing global warming, and consequent climate changes are posing major threats to the freshwater or fresh air availability. This has made it urgent to invent an appropriate water/air treatment technology that removes nanopollutants and also desalinates water to a significant extent. Carbon-based nanomaterials have generated marvelous interest in a wide range of research activities due to their high adsorption capacities. Carbon nanotubes, carbon nanotube bundles, and related materials have potential applications in gas/ion separation and water purification. Recently, gas/ion separation and water purification through carbon-based nanomaterials have received increasing attention. This review summarizes the properties of carbon nanotubes and carbon nanotube bundles related to gas separation, ion separation, and water purification using molecular dynamics simulations. Membranes-based carbon nanomaterials show promise of water purification and gas separation. These attractive properties of carbon nanotubes-based and carbon nanotube bundles-based nanomaterials make them proper candidates for gas separation, gas molecular-sieving processes, and desalination purposes in nanoscale dimensions. [ABSTRACT FROM AUTHOR]

In this study, the dispersion mechanism of aggregated carbon nanotubes (CNTs) using Triton X-100 surfactant under various concentrations is investigated with and without water molecules via molecular dynamics simulation. The obtained results showed that because of interaction between water molecules and hydrophilic segments of surfactant, water molecules play a significant role in the manner of adsorption of the surfactant on the CNT surface. In the presence of water molecules, the surfactant molecules are not able to wrap the CNTs, and they are located in the neighborhood of the CNTs. The results suggested that the creation of space between two CNTs in the absence of the surfactant is performed slowly, while, in the presence of the surfactant molecules, the creation of space between two CNTs which leads to the dispersion of the CNTs is remarkably rapid. The surfactant molecules cause to introduce more numbers of water molecules in the vicinity of and between the CNTs, and with the increasing radial distances between two CNTs, the number of water molecules is rapidly increased. The interfacial angle between two CNTs, surfactant gyration radius, and diagrams of radial distribution function between water molecules, the CNTs, and the surfactant molecules were calculated for a better description of dispersion mechanism of the CNTs by the surfactant and water molecules. [ABSTRACT FROM AUTHOR]

To facilitate the delivery of genetic material, the use of appropriate carriers such as polymers is necessary. Nanoparticles comprising of chitosan-alginate polymers were formed through pregel preparation method. Chi/Alg nanoparticles had a mean Z-Average diameter of 161.8 nm and mean zeta 29.3 mV, respectively. The ability of plasmid-complex in preventing DNA migration showed Chi/Alg nanoparticles have great capacity to maintain plasmid. The efficiency of nanoparticles for transfection of pEGFP-N1 plasmid in the cultured HEK 293 cells was measured by flow cytometry. Cell viability assays indicated that nanoparticles had no toxic effect on HEK 293 cells after 4 or 24 h. Our suitable candidate for gene delivery would be alg/chi nanoparticles. [ABSTRACT FROM AUTHOR]

In many practical situations, quality of a process or product can well be characterized by a relation between a response variable and one or more explanatory variables. This functional relationship which is commonly referred to as profile has been addressed by many researchers for the case of fixed explanatory variable. However, there are some situations where this assumption may not hold. In this paper, we try to investigate the effect of random explanatory variable on phase II monitoring of simple linear profiles. Average run length criterion is used to evaluate both the in-control and out-of-control performances of the control schemes commonly considered for phase II profile monitoring. The charting performance of the EWMA-3 control scheme has been improved using a novel technique. [ABSTRACT FROM AUTHOR]

We measured protein and mRNA levels for nine gamma-aminobutyric acid A (GABA) receptor subunits in three brain regions (cerebellum, superior frontal cortex, and parietal cortex) in subjects with autism versus matched controls. We observed changes in mRNA for a number of GABA and GABA subunits and overall reduced protein expression for GABA receptor alpha 6 (GABRα6), GABA receptor beta 2 (GABRβ2), GABA receptor delta (GABRδ), GABA receptor epsilon (GABRε), GABA receptor gamma 2 (GABRγ2), GABA receptor theta (GABRθ), and GABA receptor rho 2 (GABRρ2) in superior frontal cortex from subjects with autism. Our data demonstrate systematic changes in GABA subunit expression in brains of subjects with autism, which may help explain the presence of cognitive abnormalities in subjects with autism. [ABSTRACT FROM AUTHOR]

Earthquakes usually occur after some preliminary anomalies in the physical and chemical characteristics of environment and earth interior. Construction of the models which can explain these anomalies, prompt scientists to monitor geophysical and geochemical characteristics in the seismic areas for earthquake prediction. A review of studies has been done so far, denoted that radon gas shows more sensitivity than other geo-gas as a precursor. Based on previous researches, radon is a short-term precursor of earthquake from time point of view. There are equal experimental equations about the relation between earthquake magnitude and its effective distance on radon concentration variations. In this work, an algorithm based on Dobrovolsky equation $$ (D = 10^{0.43M} ) $$ with defining the Expectation and Investigation circles for great Tehran has been used. Radon concentration was measured with RAD7 detector in the more than 40 springs. Concentration of radon in spring, spring discharge, water temperature and the closeness of spring location to active faults, have been considered as the significant factors to select the best spring for a radon continuous monitoring site implementation. According to these factors, thirteen springs have been selected as follow: Bayjan, Mahallat-Hotel, Avaj, Aala, Larijan, Delir, Lavij, Ramsar, Semnan, Lavieh, Legahi, Kooteh-Koomeh and Sarein. [ABSTRACT FROM AUTHOR]

In order to investigate the capability of two chelators deferasirox (DFX or ICL670) and deferiprone (L) in removing lead from the body, the present research was performed. Two does levels of 40 and 80 mg/kg body weight of lead (II) chloride was given to rats as biological model for 45 days. After 45 days, some toxicity symptoms were observed in rats such as loss of hair and weight, appearance of red dots around eyes, weakness and irritability. After lead application, chelation therapy with DFX and L as mono and combined (DFX, L and DFX + L) was done for 10 days. After chelation therapy, lead level in different tissues reduced. The combined chelation therapy results showed that these chelators are able to remove lead from the body and toxicity symptoms decreased. The combined therapy results (DFX + L1) show higher efficacy and lower toxicity compared to single therapies. [ABSTRACT FROM AUTHOR]

The hypothesis that combination of deferasirox and deferiprone chelators might be more efficient as combined therapy than single therapy in removing mercury from the body was considered. Male Wistar rats were exposed to mercury vapor for 2 weeks. After mercury administration some abnormal clinical signs such as red staining around the eyes, greenish mottling on the liver, weakness, loss of hair and weight, were observed in animals. Chelators were given orally after mercury vapor application for 2 weeks. Mercury toxicity symptoms in rats decreased after drug administration. After chelation therapy, these rats were anesthetized with ether vapor and immobilized by cervical dislocation and then their heart, liver, kidneys, intestine, spleen and testicles were sampled for determination of mercury and iron concentration. The combined chelation therapy results showed that these chelators are able to remove mercury from the body and toxicity symptoms decreased. [ABSTRACT FROM AUTHOR]

Carbon dioxide is known as a hazardous material with acidic property that can be found as impurity in natural gas reservoirs with a broad range of 2 up to 40 %. Therefore, many efforts have been directed to remove and separate carbon dioxide from methane to prevent corrosion problems as well as improving the natural gas energy content. In this study, two molecular sieves, silicoaluminophosphate-34 (SAPO-34) zeotype and T-type zeolite, were synthesized by the hydrothermal method for the comparative study of adsorptive separation of carbon dioxide from methane. The synthesized adsorbents were characterized by X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy, and Brunner-Emmett-Teller techniques. These characterization tests confirmed formation of both materials with acceptable crystallinity. Both adsorbents were tested in equilibrium adsorption experiments in order to evaluate maximum capacity and adsorption affinity. Adsorption capacity of carbon dioxide and methane on SAPO-34 and zeolite T were measured in a pressure range of 0.1-2.0 MPa and temperature of 288, 298, and 308 K and fitted with the Sips and Langmuir isotherm models. The ideal selectivity of CO/CH was determined for SAPO-34 and zeolite T at the studied pressures and temperatures, indicating that the molecular sieves can be properly used for CO-CH separation or CO capturing from natural gas. [ABSTRACT FROM AUTHOR]

The present research is aimed to characterize the potential efficiency of two chelators after chromium(VI) administration for 60 days following two doses of 15 and 30 mg/kg chromium(VI) per body weight daily to male rats. However, the hypothesis that the two chelators might be more efficient as combined therapy than as single therapy in removing chromium(VI) from rat organs was considered. In this way, two known chelators deferasirox and deferiprone were chosen and given orally as a single or combined therapy for a period of 1 week. Chromium(VI) and iron concentrations in tissues were determined by flame atomic absorption spectroscopy. The combined chelation therapy results show that deferasirox and deferiprone are able to remove chromium(VI) ions from various tissues while iron concentration returned to normal levels and symptoms also decreased. [ABSTRACT FROM AUTHOR]

In this paper the information loss for fermionic superstrings 'superstring balls' in mini black holes at LHC by extending the Gottesman and Preskill method to string theory and calculate the information transformation from the collapsing matter to the state of outgoing Hawking radiation is calculated. It is found that for all finite values of ω, all information from all string emission processes experiences some degree of loss. It means that the string model is not sufficient to solve the information-loss problem. Then the fermionic superstring states at corresponding point are considered. The correspondence principle offered a unique opportunity to test the Horowitz and Maldacena mechanism at correspondence point 'the centre of mass energies around ( M/( g))'. To consider the super string states, a copy of the original Hilbert space is constructed with a set of operators of creation/annihilation that have the same anticommutation properties as the original ones. The total Hilbert space is the tensor product of the two spaces H⊗ H, where in this case H denotes the physical quantum states space of the fermionic string. It is shown that fermionic string states can be represented by a maximally entangled two-mode squeezed state of the physical and unphysical spaces of fermionic string. Also, the entropy for these string states is calculated. It is observed that black hole entropy matches the fermionic superstring entropy at transition point. This means that our result is consistent with correspondence principle and thus HM mechanism in string theory works. Finally the signature of fermionic string ball at LHC is studied. When superstring balls produce at LHC, they evaporate to Massive particles like Higgs boson. In fact string balls act as a factory for Higgs production. Then Higgs bosons decay to QCD matter. Thus an enhancement of QCD matter can be a signature of fermionic superstring ball at LHC. [ABSTRACT FROM AUTHOR]

There has been significant advancement in various aspects of scientific knowledge concerning the role of cerebellum in the etiopathogenesis of autism. In the current consensus paper, we will observe the diversity of opinions regarding the involvement of this important site in the pathology of autism. Recent emergent findings in literature related to cerebellar involvement in autism are discussed, including: cerebellar pathology, cerebellar imaging and symptom expression in autism, cerebellar genetics, cerebellar immune function, oxidative stress and mitochondrial dysfunction, GABAergic and glutamatergic systems, cholinergic, dopaminergic, serotonergic, and oxytocin-related changes in autism, motor control and cognitive deficits, cerebellar coordination of movements and cognition, gene-environment interactions, therapeutics in autism, and relevant animal models of autism. Points of consensus include presence of abnormal cerebellar anatomy, abnormal neurotransmitter systems, oxidative stress, cerebellar motor and cognitive deficits, and neuroinflammation in subjects with autism. Undefined areas or areas requiring further investigation include lack of treatment options for core symptoms of autism, vermal hypoplasia, and other vermal abnormalities as a consistent feature of autism, mechanisms underlying cerebellar contributions to cognition, and unknown mechanisms underlying neuroinflammation. [ABSTRACT FROM AUTHOR]

The origin of extragalactic diffuse gamma ray is not accurately known, especially because our suggestions are related to many models that need to be considered either to compute the galactic diffuse gamma ray intensity or to consider the contribution of other extragalactic structures while surveying a specific portion of the sky. More precise analysis of EGRET data however, makes it possible to estimate the diffuse gamma ray in Coma supercluster (i.e., Coma $\backslash $A1367 supercluster) direction with a value of $I\left( {E>{30}\,{\rm MeV}} \right)\simeq{1.9}\times {10}^{-{6}} {\rm cm}^{-{2}} {\rm s}^{-{1}}$ , which is considered to be an upper limit for the diffuse gamma ray due to Coma supercluster. The related total intensity (on average) is calculated to be ~5% of the actual diffuse extragalactic background. The calculated intensity makes it possible to estimate the origin of extragalactic diffuse gamma ray. [ABSTRACT FROM AUTHOR]

We measured protein and mRNA levels for nine gamma-aminobutyric acid A (GABA) receptor subunits in three brain regions (cerebellum, superior frontal cortex, and parietal cortex) in subjects with autism versus matched controls. We observed changes in mRNA for a number of GABA and GABA subunits and overall reduced protein expression for GABA receptor alpha 6 (GABRα6), GABA receptor beta 2 (GABRβ2), GABA receptor delta (GABRδ), GABA receptor epsilon (GABRε), GABA receptor gamma 2 (GABRγ2), GABA receptor theta (GABRθ), and GABA receptor rho 2 (GABRρ2) in superior frontal cortex from subjects with autism. Our data demonstrate systematic changes in GABA subunit expression in brains of subjects with autism, which may help explain the presence of cognitive abnormalities in subjects with autism. [ABSTRACT FROM AUTHOR]

Complex [Zn(Tppz)Cl] ( I), where Tppz = 2,3,5,6-tetrakis(2-pyridyl)pyrazine, has been synthesized and characterized by elemental analyses, IR, H NMR, cyclic voltammetry, and electronic spectral studies. Solid state structures of the complex have been determined by single-crystal X-ray crystallography. The structural determination shows that the mononuclear complex I is a 1D coordination polymer. Also an ORTEP drawing of complex I shows that the coordination geometry around the Zn(II) center is slightly distorted from regular square-based pyramidal. Crystal data for I: triclinic, spase group P $$ \bar 1 $$, a = 10.171(2), b = 10.3550(13), c = 12.239 (2) Å, α = 64.839(9)°, β = 85.736(8)°, γ = 77.842(10)°, V = 1140.3(4) Å, Z = 2. [ABSTRACT FROM AUTHOR]

Investigations were conducted to evaluate the ability of two chelators, desferrioxamine (DFO), and deferiprone (1,2-dimethy1-3-hydroxypyride-4-one, L), for the excretion of vanadium after a period of administration of vanadium salts in 6-week-old male Wistar rats. Immediately after 60 days of vanadium administration, the rats received chelators (L, DFO or L + DFO) for a period of 1 week. Chelators were given orally (L), intraperitoneally (DFO), or both to different groups of rats at two different dosage levels. After chelation therapy, animals were sacrificed by exsanguination from abdominal aorta. Blood, kidney, liver, and heart samples were collected and prepared for determination of vanadium and iron concentrations by graphite furnace and flame atomic absorption spectroscopy (GF AAS, and F AAS) methods, respectively. These chelators significantly enhanced the urinary and biliary excretion of vanadium and restored the altered levels of iron. Furthermore, the hypothesis that these two known chelators might be more effective in removing vanadium from the body as a combined treatment than as monotherapy also was tested in this study. Although there is no significant difference between these two chelators in reducing the vanadium concentration, combination therapy (L + DFO) may cause higher efficacy and lower toxicity compared with monotherapies. Collectively, the results indicate that the designed procedure might be useful for preliminary in vivo testing of the efficiency of a chelating agent. However, our findings regarding the efficacy of combination therapy should be confirmed in more experiments. This preliminary study does not provide all answers to the magnitude of the efficiency of chelating agents in vanadium toxicity, and thus, further research is warranted. [ABSTRACT FROM AUTHOR]

Total and methylmercury concentrations were assessed in muscle and liver of 141 fish samples from the northern part of the Persian Gulf. All fish samples belonged to five different species: grunt, flathead, greasy grouper, tiger-tooth croaker, and silver pomfret. In addition, Hg and methylmercury were analyzed in scalp hair of 19 fishermen living in the same coastal stations of the Persian Gulf and consuming several fish meals a week. Total mercury concentrations in fish muscle and liver ranged from 0.01 to 1.35 μg g w.w. and from 0.02 to 1.30 μg g w.w., respectively. In fish muscle, 3% of the Hg concentrations were higher than 0.5 μg g w.w., which corresponds to the maximum acceptable WHO level, while 9% were in the range of polluted fish (between 0.3 and 0.5 μg g w.w.). The highest mercury concentrations in fish muscle were observed in flathead fish at Abadan (average of 0.68 μ g g w.w.). Methylmercury fractions in fish muscle and liver amount to 34–99% (median 64%) and 24–70% (median 43%), respectively. The mean total Hg concentration in the fishermen’s scalp hair amounted to 2.9 ± 2.2 μ g g, with 68% in the form of methylmercury. Ninety-five percent of the Hg levels in the fishermen’s hair were below 10 μ g g, which is the WHO warning limit. In addition, relationships between the mercury levels in hair, on the one hand, and exposure-related factors such as Hg levels in specific fish species, regional differences, and number of fish meals, on the other hand, are discussed. It appears that a significant correlation for example exists between Hg levels human hair and fish muscle or human hair and age and that mean mercury levels in fish muscle and human hair decreased from western (Abadan) to eastern (Abbas port) coastal sites. [ABSTRACT FROM AUTHOR]

An investigation was conducted to evaluate the ability of Deferasirox (ICL670 or Exjade) following the distribution of cadmium salt in male Wistar rats. Cadmium was introduced to several groups of weanling male Wistar rats through different means, by act of drinking, feeding. A control group was fed on a diet containing normal level of iron. After a period of 30 days, all the rats administered cadmium were severely anemic and showed toxicity symptoms through loss of hair and increasing in cadmium and reduction in iron levels in blood. Chelation therapy was carried out to remove the toxic element from the body. The ability of Deferasirox chelator in removing cadmium was investigated this chelator for 1 week to the remaining rats of similar groups. The results showed that the cadmium level present in blood was significantly reduced and at the same time, iron concentration returned to the normal level. It was concluded that Deferasirox chelator is able to remove cadmium from the body and could be used for the treatment of complications and eradication of symptoms of cadmium intoxication. [ABSTRACT FROM AUTHOR]

We have shown altered expression of gamma-aminobutyric acid A (GABAA) and gamma-aminobutyric acid B (GABAB) receptors in the brains of subjects with autism. In the current study, we sought to verify our western blotting data for GABBR1 via qRT-PCR and to expand our previous work to measure mRNA and protein levels of 3 GABAA subunits previously associated with autism (GABRα4; GABRα5; GABRβ1). Three GABA receptor subunits demonstrated mRNA and protein level concordance in superior frontal cortex (GABRα4, GABRα5, GABRβ1) and one demonstrated concordance in cerebellum (GABΒR1). These results provide further evidence of impairment of GABAergic signaling in autism. [ABSTRACT FROM AUTHOR]

The concentrations of total mercury (Hg) and methyl mercury (MMHg) were determined in 78 marine sediments in the Iranian coastal waters of the Persian Gulf along nine transects perpendicular to the coastline. Total Hg ranged from 10 to 56 ng g − 1d.w. and MMHg from 0.1 to 0.4 ng g − 1 d.w. The fraction of methyl mercury accounted from 0.3% to 1.1% of the total mercury amount. The organic carbon (OC) content ranged from 0.4% to 1.8%. The present study indicates that the levels of Hg in the sediments of the Iranian coast of the Persian Gulf were all in the concentration range of unpolluted areas regarding Hg (<100 ng g − 1). The concentrations of total Hg, methyl mercury and organic carbon were generally higher in the deeper stations. Total Hg and MMHg were significantly correlated, but no significant correlations could be found between the Hg and OC levels. [ABSTRACT FROM AUTHOR]