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Biosynthesis of nanoparticles can replace the available chemical and physical methods by offering new procedures as green syntheses that have proved to be simple, biocompatible, safe, and cost‐effective. Recently, antifungal resistance has been reported against different species of Aspergillus and Candida opportunistic fungi. Selenium nanoparticles (Se‐NPs) were biosynthesized using standard strains of A. flavus and C. albicans. The presence of NPs was confirmed by UV‐Vis, FT‐IR, FESEM, EDX, XRD, and Zeta potential. Common fungal strains were cultured in Sabouraud dextrose agar medium to perform the sensitivity test based on the minimum inhibitory concentration (MIC) method in duplicate. The utilization of Se‐NPs at concentrations of 1, 0.5, and 0.25 μg/mL or in some strains even more minor than 0.125 μg/mL resulted in zero growth of fungal agents. However, antifungal drugs inhibited their growth at concentrations of 2, 4, 8, 16, and 64 μg/mL itraconazole (ITC). Also, MIC breakpoints for amphotericin B (AMB) and anidulafungin (AFG) were 2 μg/mL for defining resistance in some isolates. Based on the obtained results, biological NPs produced by Aspergillus and Candida at different concentrations exhibited favourable inhibitory effects on the growth of fungal strains.

The biosynthesis of nanoparticles stands as an uncomplicated, biocompatible, inexpensive, and secure approach for replacing the available chemical and physical methods. In this paper, Selenium nanoparticles (Se-NPs) and silver nanoparticles (Ag-NPs) were biosynthesized using Nepeta and Berberine plant extracts, respectively. UV–Vis, FT-IR, and FESEM/EDAX techniques were applied for confirming the synthesis of nanoparticles. In addition, the method of Minimum Inhibitory Concentration (MIC) was utilized to perform a sensitivity test on fungal species' leachates through the usage of Duplicate. The application biosynthesized Se-NPs and Ag-NPs at concentrations of 1 µg/mL and below caused no growth of fungal agents. However, antifungal drugs at concentrations higher than 1 µg/mL and even up to 64 µg/mL inhibited the growth of these drug-resistant fungi. A comparison of the results showed that even these nanoparticles in some cases have a better effect than the group of antifungal drugs. Therefore, the usage of biosynthesized nanoparticles is considered to be more convenient and economical due to the increasing drug resistance of opportunistic and pathogenic microorganisms towards the exerted target drugs.

Several side effects and drug resistance accompany the current therapies for Leishmaniasis. Nanoliposomal curcumin is applied as a new therapy approach instead of current therapy. In this study, nanoliposomal curcumin was prepared using thin-film hydration method and characterized based on encapsulation efficiency, size, and zeta potential. Curcumin was successfully loaded into nanoliposomes with an encapsulation efficiency of 92%. The surface charge of the nanoparticle was neutral, and the size of nanoparticle was 176.5 nm. Nanoliposomal curcumin is in spherical shape without any agglomeration. Cell viability assay was performed on HFF cell line to show biocompatibility of liposome nanoparticles. Anti-Leishmanial effect of different concentrations of liposomal curcumin (0.05-30 μg mL-1) and amphotericin B (25 μg mL-1) were studied on Leishmania major [MRHO/IR/75/ER] at various hours (24, 48, and 72) using hemocytometer technique. Nanoliposomal curcumin inhibitory concentration (IC50) at hours 24, 48, and 72 were 6.41, 3.8, and 2.33 µg mL-1, respectively. As prepared nanoliposomal curcumin showed a significant antileishmanial effect and induced a better and more tangible effect on the survival of L. major promastigotes and could be suitable candidates for further investigations.

Introduction: According to the literature, Central Retinal Arteriolar Equivalent (CRAE), Central Retinal Venular Equivalent (CRVE), and Artemio Venule Ratio (AVR) are three important markers in determining the changes of retinal artery. These markers are employed as an indicator of cardiovascular effects in workers. This study aimed to evaluate the changes in retinal micro vascular responses in workers exposed to short-term exposure to particulate matters caused by occupational processes using CRAE, CRVE, and AVR markers. Materials and Methods: In this study, 96 workers exposed to job-related pollution in a tile and ceramic company were investigated. Fundus photos of these people were analyzed via ARIA software using the related protocols. The data were investigated employing Kolmogorov–Smirnov and Mann-Whitney tests as well as the correlation and regression tests. Results: No significant difference was observed in the ocular parameters of smokers and non-smokers. Cardiovascular parameters had no significant correlation with CRAE and CRVE as well as breathable and inhalable dust; however, these parameters had a direct and significant correlation with AVR, PM10, and PM2.5 particles. Conclusion: The results did not show any changes in the retinal artery in workers who were exposed to job-related pollution. Moreover, no significant relationship was found between retinal artery changes and cardiovascular parameters. However, more large-scale studies are needed to clarify the relationship of particulate air pollutants with CRAE, CRVE, and AVR changes.

Plate-like CuS particles were prepared by a facile chemical synthesis method. The effects of thiourea contents on phase, morphology and electrochemical properties were studied by modern characterization techniques. A mechanism was proposed for morphology evolution from spherical to plate-like with the increase of amounts of thiourea. The precipitation of [Cu4(tu)9](NO3)4·4H2O complex was postulated as a reason for the crystallization of plate-like CuS particles which showed a pseudocapacitor behavior with a specific capacitance of 517 F g−1 at a current density of 1 A g−1. The appropriate electrochemical characteristics were attributed to the unique structure of plate-like CuS particles, improving the charge transport and electrolyte diffusion.

This study investigated the effects of temperature and the current density on the production of an Al–Li master alloy using electrolysis. The current efficiency and the specific energy consumption were calculated according to Faraday’s law to determine optimal conditions for production of the Al–Li master alloy. Solid aluminum and graphite were used as the cathode and the anode, respectively. The LiCl–KCl eutectic molten salt was used as a lithium-containing electrolyte. Different current densities were applied to obtain the optimum condition. In addition, different temperatures were investigated at the optimum current density during the deposition of lithium. Scanning electron microscopy, optical microscopy, and the X-ray diffraction analysis were used to investigate the microstructure and phase compositions. Atomic absorption spectroscopy was used to measure the existing lithium. The results showed that electrolysis at 620°C and a current density of 0.9 A/cm2 at 4 V for 3 h leads to the formation of an Al–17.43 wt % Li master alloy. The current efficiency and the specific energy consumption for the optimum conditions were found to be 96% and 16.08 kWh/kg, respectively.

Detecting the hazardous gases for monitoring air pollution and medical diagnosis make highly sensitive gas sensors appeal to many researches. In this paper, benefiting from unique properties of noble metals, Al-doped ZnO based Ethanol sensors were fabricated and characterized in three structures including Al: ZnO thin film, Silver and Gold nano-islands on Al: ZnO thin film. The Silver and Gold thin films turn to nano-islands after a simple annealing process. The XRD analysis of the sputtered Al: ZnO layer indicates the wurtzite crystal structure of the layer with a peak at (002) plane. Moreover, the sensitivity study reveals that Nano-islands of noble metals substantially affects the sensitivity of the sensors. The decorated Gold nano-island Al: ZnO Ethanol sensor has the highest response showing an amount of 45. The response of Al: ZnO and Silver decorated Al: ZnO sensors are virtually identical to all concentrations of Ethanol, whereas the Al: ZnO gas sensor with Gold nano-islands has the substantial sensitivity for different concentrations. In addition, the response times of the sensors are 85, 70 and 90 s for Al: ZnO, Al: ZnO with Ag islands and Al: ZnO decorated by Au islands, respectively. The recovery time of Al: ZnO sensor decorated by Au islands is about 23s, while the recovery time of the Al: ZnO and Al: ZnO decorated by Silver islands are 360 and 370s, respectively. Hence, the simple annealing process on the sputtered gas sensor with a thin layer of Gold makes nano-islands on the sensor which elevates the performance of Ethanol sensing due to the high sensitivity and sensitivity of the sensor.

The hydrogen gas sensing properties of carbon-doped ZnO nanotube has been theoretically investigated by employing first-principles density functional theory in combination with non-equilibrium Green's function. The figure of merits is creating the new states in ZnO nanotube structure by adding carbon substitution for an oxygen site. The calculation of adsorption energy indicates strong chemical adsorption of hydrogen on the outside and inside of carbon-doped ZnO nanotube. Moreover, density of state, current-voltage and sensor response have been performed for energetically favorable adsorption geometries of hydrogen. The involvement of carbon valence electrons in the chemical adsorption of hydrogen has been examined by partial density of state diagram. The current-voltage diagram of carbon-doped ZnO nanotube indicates negative-differential resistance trend. This trend has been disappeared after the chemical adsorption of hydrogen. The sensor response calculations reveal the high response of the sensor occurs in 3.5 V on the outside and inside of carbon-doped ZnO nanotube.

This paper is to demonstrate an efficient cell capture assay based on employing patterned highly vertical zinc oxide (ZnO) nanorods. Hydrophilic properties of ZnO nanorods, as well as nano topographic nature of the outer surface of cells were exploited as separation mechanism. MCF-7 and MDA-MB-231 breast cancer cell lines were captured on the patterned or not patterned ZnO nanorods. For these substrates, significantly improved capture efficiency was achieved by patterning the nanorods surfaces. The capture efficiency of MCF-7 cell species increased from 0 to over 84 % through the conversion of flat substrates to patterned nanorods surfaces. Additionally, efficiency promotion was observed by increasing the incubation time from 1 hour to 4 hours for the MCF-7 cells, resulting in maximum capture efficiency of 98.4% in the case of patterned nanorods. However, MDA-MB-231 cancer cells, as invasive late-stage cell species, were expectantly found to show lower efficiencies, maximum of 86%. Intensively and strongly adhered breast cancer cells to nanorods with formed lamellipodia have been reported for proposed ZnO nanostructured substrates. Interestingly, both types of breast cell species depicted different cell areas, offering various focal adhesions. This allows for selective separation of not only the breast cancer cells from the normal blood species but also these two cell types while retaining viability.

The application of biological nanoparticles (NPs) can be considered as a way to overcome the problem of antifungal resistance in pathogenic fungi. This study takes a new approach to biosynthesized NPs influence on the expression of CYP51A and HSP90 antifungal resistance genes in Aspergillus fumigatus and A. flavus, and comparison with antifungal agents. Selenium NPs (Se-NPs) were biosynthesized using Aspergillus strains and their production was proved by several methods including, UV-Vis, XRD, FTIR, FESEM, and EDX techniques. The minimum inhibitory concentrations (MICs) of Aspergillus strains were determined using the CLSI M38-A2 broth microdilution method. The differences in expression levels of CYP51A and HSP90 genes were examined between untreated and treated of A. fumigatus and A. flavus using itraconazole and amphotericin B and biosynthesized Se-NPs through real-time PCR. After confirming the results of NPs synthesis, the MIC of itraconazole and amphotericin B against A. fumigatus and A. flavus was 4 μg/mL. Based on the real-time PCR results, the obtained ∆∆CTs for these strains were -0.18, -1.46, and -1.14. Whereas the MIC values for treated samples with Se-NPs have decreased to 0.5 μg/mL, and the ∆∆CTs for these were -0.25, -1.76, and -1.68. The expression of CYP51A and HSP90 genes was significantly down-regulated through the use of Se-NPs against A. fumigatus and A. flavus. This article is protected by copyright. All rights reserved.

Catalyzed peroxidation of unsaturated lipid in animals and plants intimately is linked to the activity of 15-Lipoxygenase enzymes. Lipoxygenases (LOXs) are well known to play an important role in many acute and chronic syndromes such as inflammation, asthma, cancer, and allergy. In this study, a series of mono prenyloxycarbostyrils were synthesized and evaluated as potential inhibitors of soybean 15-Lipoxygenase (SLO) and their inhibitory potencies were compared to mono prenyloxycoumarins which had been reported in the previous works. The synthetic compounds inhibit lipoxygenase enzyme by competitive mechanism like the prenyloxy coumarins. The results showed that position and length of the prenyl moiety play the important role in lipoxygenase inhibitory activity. Among all of the synthetic compounds (coumarin and carbostyril derivatives), 5-farnesyloxycoumarin and 8-farnesyloxycarbostyril demonstrated the best inhibitory activity by IC50 values of 1.1 µM and 0.53 µM, respectively.

Background Dysrhythmia and sudden cardiac arrest occur more likely in HIV patients than healthy subjects. Thus, we need to examine dysrhythmias adverse effects of medications including Efavirenz as early as possible especially in young subjects. Hypothesis Efavirenz might have contributed to increased risk of developing common types of dysrhythmia in young HIV infected patients. Methods We performed a retrospective cohort study among 62 patients on Efavirenz and 38 controls. All participants were under 40 years old without cardiovascular disease. Total significant dysrhythmia in 24‐hour ECG monitoring was the primary endpoint determined as the composite of high premature ventricular contraction (PVC) (>500 beats per 24 hours), high premature atrial contraction (PAC) (>500 bp24h), sinus pause, atrioventricular blocks, ventricular tachycardia, prolonged QTc, and low heart rate variability (HRV). Modified composite dysrhythmia consisted of low HRV (SD of normal‐to‐normal [SDNN]), high PVC and prolonged QT. Results Mean heart rate, Efavirenz regimen, male gender, and CD4 count predicted total dysrhythmia. Odds ratios were 1.108, 2.90, 4.36, and 0.96, respectively. The incidence of total dysrhythmia, high PVC, high PAC, low HRV(SDNN), and prolonged QTc were 54.8%, 41.85%, 9.71%, 45.2%, and 12.9% in patients on Efavirenz against 42.11%, 31.64%, 0%, 34.2%, and 7.91% in controls, respectively (p‐values: .031, .001

Nickel sulfide composite powders were prepared through solution combustion synthesis using nickel nitrate as both nickel source and oxidant, together with various amounts of mixed urea-thiourea fuels. The precursor solutions were ignited by conventional and microwave heating. The combustion reaction behavior, phase structure and optical properties were analyzed as a function of fuel amounts. The combusted powders were composed of α-NiS, NiS2, Ni3S2 and NiO phases related to the fuel content and heating mode. The higher combustion temperature in microwave heating led to the oxidation of sulfide phase to nickel oxide. The highest amount of NiS phase with the maximum removal efficiency of methylene blue (MB) (∼ 52%) was achieved when conventional synthesis procedure with a urea to thiourea molar ratio of 2:0.75, was employed.

Background: We performed a meta‐analysis to clarify the association of endothelial nitric oxide synthase (eNOS) and angiotensin I-converting enzyme (ACE) gene polymorphisms with retinopathy of prem...

Paper description: The industrial application of enzymes which can withstand harsh conditions has greatly increased in recent years and extremozymes are good alternatives to mesophilic enzymes in industries. Chitinase is one of the most important hydrolytic enzymes with a variety of biotechnological applications. We describe chitinase from a haloarchaeal strain belong to the genus Natrinema isolated from a hypersaline lake in Iran. To our knowledge, our investigation is among the first studies on chitinolytic activity of halophilic archaea. This study revealed the strong potential of the genus Natrinema to produce chitinase at high salt concentrations without Mg 2+ requirement. Abstract: Halophiles produce stable enzymes under extreme conditions. The scant information about chitinolytic haloarchaea led us to conduct the present study in order to isolate and screen native halophilic archaea with chitinolytic activity and to optimize the enzyme production conditions. Among 500 haloarchaeal strains isolated from water samples from different hypersaline lakes of Iran, five strains showed chitinolytic activity. Based on biochemical, morphological and molecular analyses, we established that all five potent strains belonged to the genus Natrinema . Besides, observing chitinase function in culture media, through an additional molecular test the presence of the chitinase gene in chitinase-producing strains was also confirmed by PCR amplification. Compared with other potent strains, Natrinema sp. strain BS5 showed significant chitinase production. The production of chitinase in strain BS5 accompanied growth, started at the logarithmic phase and increased to its maximum level at the beginning of the stationary phase. Maximum chitinase production was obtained at 37˚C, pH 7.5, 3 M NaCl and 1% colloidal chitin. The strain BS5 showed 38%, 30%, 24% and 28% decreases in enzyme production at 40˚C, pH 8, 3.5 M NaCl and 0.5% substrate, respectively. This strain was able to produce the enzyme in NaCl 4 M and in the absence of MgCl 2 and MgSO 4 . This study revealed the strong potential of the genus Natrinema to produce chitinase at high salt concentrations without Mg 2+ requirement. https://doi.org/10.2298/ABS180525049Y Received: May 25, 2018; Revised: September 27, 2018; Accepted: October 4, 2018; Published online: October 30, 2018 How to cite this article: Yavari-Bafghi M, Babavalian H, Amoozegar MA. Isolation, screening and identification of haloarchaea with chitinolytic activity from hypersaline lakes of Iran. Arch Biol Sci. 2019;71(1):71-81.

Background: Dyslipidemia, a genetic and multifactorial disorder of lipoprotein metabolism, is defined by elevations in the levels of total cholesterol, low-density lipoprotein cholesterol (LDL-C), non-high-density lipoprotein cholesterol (non–HDL-C), triglyceride, or some combination thereof as well as lower levels of high-density lipoprotein (HDL) cholesterol. Objectives: This study aimed to investigate the prevalence and predictors of dyslipidemia in children and adolescents in the Yazd Greater Area, Yazd, Iran. Methods: This cross-sectional study was conducted as a part of the national project implemented in Yazd Greater Area, Yazd, Iran. The sampling was performed using a multi-stage cluster sampling method on three age groups of girls and boys, including 6-9, 10-14, and 15-18 years old. Out of the total 1,035 children and adolescents who initially participated in this study, only 784 participants remained until the end. Data collection was performed using lifestyle questionnaires including Kiddie-SADS-Present and Lifetime Version software. Results: The rate of high triglyceride was estimated at 1.4% and 4.2% in 6-9 and 10-18 years old children and adolescents, respectively. Moreover, the prevalence of high cholesterol, LDL, and HDL were obtained at 3.2%, 3.2%, and 25.6%, respectively. The prevalence of dyslipidemia in the total population of children and adolescents was estimated at 64.6% and 57.3% in boys and girls, respectively (P=0.038) in terms of demographic variables. Gender and increase in body mass index (BMI) were significantly associated with dyslipidemia with OR=1.35; 95% CI: 1.01-1.81 and OR=13.781; 95% CI: 3.78- 46.43, respectively. However, after adjustment for other factors, only an increase in BMI was significantly associated with dyslipidemia (OR=16.08; 95% CI: 4.49-57.59). Conclusion: Overweight and obese adolescents had a higher concentration of serum blood triglycerides, compared to their counterparts. Weight control, lifestyle, and diet modification are three ways to reduce lipid disorders in adolescents.

Biosynthesis of nanoparticles can stand as a replacement for the available chemical and physical methods by offering new procedures as green syntheses that have proved to be simple, biocompatible, safe, and cost-effective. Considering how nanoparticles with a size of 1 to 100 nanometers contain unique physical and chemical properties, recent reports are indicative of observing the antifungal qualities of selenium nanoparticles (Se-NPs). Recently, the observance of antifungal resistance towards different species of these fungi is often reported. Therefore, due to the antifungal effects of biological nanoparticles, this study aimed to investigate the exertion of these nanoparticles and evaluate their effects on the growth of fungal pathogens. Se-NPs were biosynthesized by the application of wet reduction method, which included specific concentrations of Aspergillus flavus and Candida albicans. The presence of nanoparticles was confirmed by methods such as UV-Vis spectroscopy, FT-IR analysis, and FESEM electron microscope that involved FESEM and EDAX diagram. The fungal strains were cultured in sabouraud dextrose agar medium to perform the sensitivity test based on the minimum inhibitory concentration (MIC) method in duplicate. The utilization of Se-NPs at concentrations of 1 µg/ ml and below resulted in zero growth of fungal agents. However, their growth was inhibited by antifungal drugs at concentrations of 2 µg/ ml and higher. Based on the obtained results, biological nanoparticles produced by fungal agents at different concentrations exhibited favorable inhibitory effects on the growth of fungal strains.

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Background: The TGF-α TaqI C >T polymorphism is a well-characterized variant for nonsyndromic cleft lip and/or palate (NS CL/P), but it has shown inconsistent results of association with nonsyndromic CL/P across a number of studies. Thus, we have performed this case-control study to clarify the association between the TGF-α TaqI C >T polymorphism and NS CL/P risk. Methods: One-hundred ten cases with NSCL/P and 110 controls were recruited to the current study. We have genotyped the TGF-α TaqI C >T polymorphism using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. The odds ratio (OR) and 95% confidence interval (CI) were applied for strength of association TGF-α TaqI C >T polymorphism with NSCL/P. Results: The TGF-α TaqI C >T polymorphism CC, CT and TT genotypes frequencies in the NSCL/P cases were 30.9%, 57.3% and 11.8%, respectively while the corresponding frequencies in the controls were 37.3%, 52.7% and 10.0%, respectively. The frequency of C and T alleles in the case were 59.5% and 40.5%, respectively while the corresponding allelic frequencies in the controls were 63.6% and 36.4%. There was no significant difference in the genotype and allele frequency for TGF-α TaqI C >T polymorphism between cases and controls. The minor allele frequency (MAF) of TGF-α TaqI C >T polymorphism among healthy controls was 0.36. Conclusion: Our study indicates that the TGF-α TaqI C>T polymorphism was not significantly associated with increased risk of NS CL/P in the Iranian population. However, our results still need to be confirmed by further large and well-designed case-control studies. Keywords: Nonsyndromic Cleft Lip and/or Palate, TGF-α gene, TaqI C >T, Polymorphism

A polyurethane (PU)-based powder coating reinforced with vinyltrimethoxysilane (VTMS)-functionalized ZrO2 nanoparticles (V-ZrO2) for thermal stability was developed. Chemical structure, microstructure and thermal degradation kinetics of the prepared coatings were investigated. The peak of aliphatic C&ndash, H vibrating bond in the Fourier transform infrared (FTIR) spectrum of V-ZrO2 was a signature of VTMS attachment. Scanning electron microscopy (SEM) images reveled that, by increase of V-ZrO2 content from 0.1 to 0.3 wt.% and then 0.5 wt.%, some agglomerations of nanoparticles are formed in the PU matrix. Thermogravimetric analysis (TGA) of the PU/V-ZrO2 powder coatings was performed at different heating rates nonisothermally to capture alteration of activation energy (Ea) of degradation of PU/V-ZrO2 powder coatings as a function of partial mass loss by using Friedman, Kissinger&ndash, Akahira-Sunose (KAS), Ozawa&ndash, Wall&ndash, Flynn (FWO) and modified Coats&ndash, Redfern isoconversional approaches. It was observed that by addition of 1 wt.% V-ZrO2 to PU resin the early state degradation temperature at 5% weight loss increased about 65 &deg, C, suggesting a physical barrier effect limiting the volatility of free radicals and decomposition products. Incorporation of 5 wt.% ZrO2 led to about 16% and 10% increase in Ea and LnA of blank PU, respectively, which was indicative of higher thermal resistance of nanocomposite powder coatings against thermal degradation. There was also obvious agreement between model outputs and experimental data. The results reveal that nanocomposite coating shows superior thermal properties compared to neat PU powder coatings, and the presence of nano ZrO2 in sufficient amount causes retardation of the thermal decomposition process.

By having toxic effects on human health, oxyanion contamination in wastewater is considered a priority among environmental concerns to be resolved. Widespread applications of the oxyanions in various industries and metal mining activities in certain environments resulted in high concentrations of these materials especially effluent in their toxic forms. One of the acceptable methods considered by a number of researchers to reduce their toxicity is bioreduction of oxyanions by microorganisms which is considered as one of the bioremediation methods. However, the major problem for bioremediation by conventional methods is the extreme conditions of industrial effluents, such as high salinity, high or low pH, and high temperature. Nature itself has given the solution to this problem, i.e., extremophiles, microorganisms that survive in these harsh conditions. Due to their ability in reducing metalloids and detoxifying them, they are suitable candidates for biological treatments. Here, the efficacy of various extremophile groups in bioremediation of major oxyanions including arsenic, selenium, chromium, and tellurium is reviewed.

In this work, two simple, facile, and low cost microwave assisted simple and Pechini sol gel were applied to synthesize SiO2 nanoparticles. Through these processes, effect of different parameters on particles size and morphology were investigated. Formation time and size of product were remarkably reduced by using microwave. These nanoparticles show remarkable photocatalytic properties under irradiation with UV light. Obtained nanoparticles were also used as filler in two different polymeric matrixes (polycarbonate and polystyrene) and their flame retardancy properties were investigated to be unique.

Nickel sulfide powders were synthesized through solution combustion method using a suitable combination of thiourea fuel as reducing/sulfidizing agent with glycine fuel as auxiliary reductant agent. Effects of fuel contents on the combustion behavior, phase evolution, microstructure and optical properties were investigated by infrared spectroscopy, thermal analysis, X-ray diffractometry, electron microscopy and diffuse reflectance spectrometry techniques. Single phase NiS2 powders were formed using thiourea fuel at higher content, while a mixture of nickel sulfide phases was appeared in the presence of glycine fuel. The amount of different sulfide phases was considerably dependent on the thiourea content. Particle size of the as-combusted powders increased with the increase of thiourea; while the existence of glycine fuel together with thiourea led to the bulky microstructure. Maximum photodegradation (~ 56%) of methylene blue was achieved by as-combusted powders at a thiourea fuel to the oxidant molar ratio of 1, as a consequence of their high ability of light absorption.

Because of the drug resistance and toxic side effects observed following administration of many antibacterial drugs, novel strategies are highly needed for treatment of bacterial diseases. Chitosan important immune system stimulators, is found in cockroaches who are living in contaminated sites. this substance appears to help the cockroaches strongly deal with pathogens. The aim of this study was to extract thechitosan from nymph and adult stage of both Blattella germanica and Preplenta amercana and evaluate its antibactral and antifungal activities. To demineralize the insect's integument powder, HCl 1 normal was used. In addition, the process of deproteination was performed by using(for transformation integument powder into chitin )NaOH 1normal. Subsequently, by NaOH 50% chitin was deastelated[F1] to chitosan. Finally chitosan was dissolved in lactic acid 1 % and preserved until the time of antitrichomonal and antifungal activity examinations.. Chitosan extracted from cockroaches shows beneficial effects on Gram + bacterias. For instance, it has shown powerful impacts on E.Coli and Estafilococos oreous, but not on fungi. The current study revealed that chitosan has excellent antibacterial activities and could be considered as a new approach to fight various bacterial agents. Chitosan is also was effective against Fungi (in a high pH environment) Furthermore, we identified biochemical processes resulted in chitin deacetylation to chitosan within the insect's body. There are evidence showing that the blockage of chitin makes the insects much more vulnerable to microbial infections.

In this paper, the compressive strength, tensile strength and growing rate of compressive strength in 3, 7, 28 and 90 day ages for steel, polypropylene and hybrid steel-polypropylene fiber reinforced concrete with different water to binder ratios (0.4 and 0.5) in a real marine condition and tidal zone were determined. Moreover, regarding a large number of gathered data from the other researches, new equations between compressive strength, tensile strength and elasticity modulus for different types of steel fiber reinforced concrete were proposed. Finally, proposed equations were compared and verified for a marine environment. Based on marine environment results, compressive strength of polypropylene and hybrid steel-polypropylene fiber reinforced concrete were about 18 % and 5 % greater than plain concrete in 90 day ages, respectively and steel fibers had not meaningful effect on compressive strength in 90 day ages. By increasing the water to binder ratio, the compressive strength of plain concrete and steel fiber reinforced concrete was decreased about 18 % and 25 %, respectively. Also in 28 and 90 days, steel fiber reinforced concrete tensile strength was increased about 15 % in 0.4 water to binder ratio and 20 % in 0.5 water to binder ratio rather than plain concrete. Effect of steel fiber in increment of plain concrete tensile strength in 0.5 water to binder ratio was higher than 0.4. Steel fiber reinforced concrete elasticity modulus was lower than related plain concrete and with increasing the compressive strength, the difference between elasticity modulus of steel fiber reinforced concrete and plain concrete was decreased. DOI: http://dx.doi.org/10.5755/j01.ms.24.2.17909

Nickel sulfide/reduced graphene oxide composite powders were prepared by solution combustion method using nickel nitrate and graphene oxide as oxidants together with thioacetamide, either alone or admixed with glycine, as fuel. Graphene oxide was in-situ reduced during combustion process. Phase, structure, and microstructure of the combusted powders were tuned by proper use of the type and amount of fuels. With the increase of glycine as an auxiliary fuel, bulky microstructures of sintered particles were appeared. The nickel sulfide/reduced graphene oxide composite powders showed the pseudocapacitive behavior with a high specific capacitance of 305 F g−1 at a current density of 1.1 A g−1. The high conductivity of reduced graphene oxide and distribution of nickel sulfide nanoparticles on reduced graphene oxide sheets led to the high capacity retention of 91% after 3000 cycles.

A facile and cheap method for the fabrication of WC-Al2O3 composite powder was proposed. Thermodynamic calculations indicate that aluminothermic reduction of WO3 in WO3:xAl:(4–1.5x)C mixture is accompanied by a great deal of heat, so carbothermic reduction reaction (endothermic) becomes activated in the system. By substitution of aluminum with carbon, the formation of unwanted W2C phase can be prevented because of less thermodynamic stability at lower temperatures. For the verification of the proposed reaction mechanism, various WO3:xAl:(4–1.5x)C mixtures (1.1≤x≤2) were heat-treated in a domestic microwave oven. The results showed that the type of reaction is self-propagating high temperature synthesis (SHS) when 1.4≤x≤2. Lower amount of Al in WO3:xAl:(4–1.5x)C mixtures results in a higher formation of WC. A W2C-free WC-Al2O3 composite was obtained by continuation of microwave heating in an isolated atmosphere, after the occurrence of SHS reaction in a mixture containing 1.4 mol of Al. Results also showed that when x≤1.3, type of reaction becomes gradual, which in turn brings about the incompleteness reaction and residue of initial reagents.

A simple, easy, and low-cost process for the fabrication of tungsten carbide (WC) powder through microwave heating of WO3–C mixtures was developed. Thermodynamic calculations and experimental investigations were carried out for WO3–C and W–C systems, and a formation mechanism was proposed. In the results, for the synthesis of WC, the use of over stoichiometric amount of C together with a specially assembled experimental setup (which effectively retains heat in the system) is necessary. The WC powder is successfully obtained by heating WO3:5C mixture for 900 s in a domestic microwave oven.

Background and Aims: Because of the toxicity and side-effects of synthetic drugs, there is a growing interest in biomedical plants. The aim of this study was to evaluate in vitro antileishmanial activity of Carum copticum essential oil against Leishmania (L) major. Materials and Methods: Nineteen experimental groups were designed to determine the effect of Carum copticum essential oil against L. major and compare it with Meglumine antimonite. Group 1 was the control group and included 200 µl of RPMI 1640 plus 2×105 cells/ml promastigotes. Groups 2-10 included the aforementioned substances plus 10 µl of 0.01, 0.02, 0.05, 0.1, 0.2, 0.5, 1, 2 and 3 µg/ml of Carum copticum essential oil respectively. Groups 11-19 were similar to groups 2-10 but Meglumine antimonite (0.01, 0.02, 0.05, 0.1, 0.2, 0.5, 1, 2 and 3 µg/ml) was used instead of Carum copticum essential oil. All the experiments were repeated five times. After 8 hours, the antileishmanial activities of studied substances were determined. Results: Up to concentration of 0.5 µg/ml, no effect was observed with both substances. In comparison to control group, at 1 and 2 µg/ml, Meglumine antimonite had no effect on Leishmaniasis (p>0.05) while Carum copticum essential oil significantly decreased Leishmaniasis viability (p

The application of solid-state sensors in the detection of hydrogen gas is a positive step to prevent safety issues created by hydrogen leakage. In this paper, the absorption of hydrogen molecules on the outside and inside of ZnO nanotube and ZnO nanowire has been investigated by employing density functional theory. Results demonstrate that hydrogen gas is physically absorbed at distances between 2.20 A and 2.26 A from the surface of ZnO nanotubes and ZnO nanowire, respectively. The hydrogen molecule has the same adsorption behavior on both the outside and the inside wall of ZnO nanotube; as a result, the effective surface of ZnO nanotube increases. On the other hand, the adsorption of hydrogen molecules leads to a shift of the Fermi level toward valence band edge. This shift is more pronounced in ZnO nanowires, which leads to a better sensitivity toward hydrogen molecules. However, ZnO nanotubes could provide more surface-to-volume ratio, which also increases the sensitivity of the nanostructure.

The aim of the present study was to examine the relation between two paraoxonase1 (PON1) polymorphisms, Q192R and L55M and susceptibility to gastric cancer in an Iranian population. In this case-control study the PON1 polymorphisms were assessed in 90 gastric cancer patients and 90 healthy controls by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Regarding PON1 Q192R polymorphism, a significant increase in the R allele in the patient group compared with the controls (p value = 0.0006) While the Q allele was more frequent in the control group. No significant difference was found in the genotype or allele frequency of the L55M polymorphism between healthy individuals and patients with gastric cancer. Our results demonstrated the protective effect of Q allele against gastric cancer.

Root-knot nematode, Meloidogyne javanica is a major causal agent of plant diseases on summer crops in fields and greenhouses. In order to reduce environmental concerns, compounds having pesticidal capacity with insignificant residue can be a good alternative to synthetic pesticides. This study was undertaken to investigate the nematicidal capability of ozone under Petri dish (in vitro) and pot (in the rhizosphere of tomato seedlings cv. Super Chief) conditions. The experiments were conducted based on Completely Randomized Design in four replicates with two antimicrobial materials, Cadusafos (0.5, 1.0, 1.5, 2.0, 2.5 and 3 g kg-1 soil) and ozone (0.05, 0.1, 0.2, 0.4, 0.8 and 1.6 g kg-1 soil). Results confirmed the significant in vitro controlling effect of ozone on nematode egg (85%, in 0.4 g kg-1 soil) and second stage juvenile (72%, in 0.4 g kg-1 soil) populations. Also a toxic effect of ozone was observed on the nematode pathogenicity, i.e. galling (83%, in 0.4 g kg-1 soil), on tomato root in pot assays. Plant morphological traits (i.e. root fresh weight, foliage fresh weight, and stem length) were not significantly affected by ozone. Therefore, taking into account the principles of safety in the application of ozone, this material can be suggested as an alternative nematicide, at least at limited and controlled condition. RESUMO O nematoide das galhas, Meloidogyne javanica, é um dos principais agentes causadores de doenças de plantas em cultivos de verão em campos e estufas. A fim de reduzir as preocupações ambientais, os compostos com capacidade pesticida com resíduos insignificantes podem ser uma boa alternativa aos pesticidas químicos inseguros. Este estudo foi realizado para investigar a capacidade nematicida do ozônio sob condições de placa de Petri (in vitro) e em vaso (na rizosfera de mudas de tomateiro cv. Super Chief). Os experimentos foram conduzidos com delineamento inteiramente casualizado em quatro repetições com dois materiais antimicrobianos Cadusafos (0.5, 1.0, 1,5, 2,0, 2,5 e 3,0 g kg-1 solo) e ozônio (0,05, 0,1, 0,2, 0,4, 0,8 e 1,6 g kg-1 solo). Os resultados confirmaram o efeito significativo do controle in vitro do ozônio sobre as populações de ovos (85%, em 0.4 g kg-1 solo) de nematoides e juvenis de segundo estádio (72%, in 0,4 g kg-1 solo). Também foi observado um efeito tóxico do ozônio na patogenicidade do nematóide, isto é, irritação (83%, em 0.4 g kg-1 solo) na raiz do tomateiro em ensaios em vasos. As caracterticas morfolicas das plantas (i.e., peso fresco da raiz, peso fresco da folhagem e comprimento do caule) não foram significativamente afetados pelo ozôno. Portanto, levando em conta os princípios de segurança na aplicação do ozônio, este material pode ser indicado como um nematicida alternativo, pelo menos em condições limitadas e controladas.

Cobalt sulfide powders (CoS, Co9S8 and CoS1.97) were synthesized by solution combustion method using conventional and microwave heating routes. The powders were obtained using cobalt nitrate as both cobalt source and oxidizer together with proper amounts of thiourea as sulfidizing agent and glycine as an auxiliary reductant. Effects of thiourea and glycine amounts in conjunction with the type of combustion route, on the phase constituents, microstructure and optical properties were studied using infrared spectroscopy, thermal analysis, X-ray diffractometry, electron microscopy and diffuse reflectance spectrometry techniques. The results revealed that single phase cobalt sulfides can be delivered by precise adjustment of thiourea and glycine amounts and a proper heating (conventional or microwave) route. Co9S8 single phase was obtained using equal amounts of thiourea and glycine by both microwave and conventional heating modes. Using thiourea/glycine ratio of 1.5, leads to the formation of CoS1.97 single phase by conventional heating, while CoS was obtained when microwave heating was applied. Increasing the amount of thiourea caused particle size increment. Maximum photocatalytic degradation efficiency (89 and 89.5%) of methylene blue was obtained at pH = 9 for microwave combusted samples. Quenching tests in the presence of •OH− radical scavenger (isopropyl alcohol) showed that the major oxidizing species were • OH− radicals.

In this research work, microwave-assisted self-propagating high-temperature synthesis (SHS) process was employed for the fabrication of titanium diboride (TiB2) compound from TiO2–B2O3–Mg mixtures. Thermodynamic evaluations of this system and its relevant subsystems revealed that TiB2–MgO composite powder can be easily produced by a SHS reaction. However, experimental results of a TiO2 : B2O3 : 5Mg mixture heated in a domestic oven showed the formation of some intermediate compounds such as Mg3B2O6, presumably due to some degree of Mg loss. The optimum amount of Mg in TiO2 : B2O3 : xMg mixtures, yielding the highest amount of TiB2 phase, was found to be around 7 mol, i.e., 40 mol% more than the stoichiometric amount. Experimental results revealed that a pure TiB2 compound could be obtained by leaching the unwanted by-products in an HCl acid solution. Scanning electron microscopic observations and Scherrer calculations showed that the produced TiB2 contains sub-micron (150–200 nm) particles, where each particle consists of a number of nanosized (32 nm) crystallites.

Hydraulic fracture is one of the key methods in well stimulation to increase production of oil and gas. Crack Opening Displacement (COD) is of great importance in this method since it is in direct relation with permeability and production rate. In this paper COD is measured by a distinct element model which has been validated by an exact solution. A comprehensive study has been performed on confining pressure effect on COD which is neglected in the analytical solution. Numerical results showed that confining pressure considerably affects COD. A multi-parameter regression (considering effect of confining pressure, rock mass properties and fluid pressure) was performed on numerical results which resulted in an equation. The proposed equation considers the effect of confining pressure and its results are in good agreement with numerical results. Keywords: Hydraulic fracture, COD, Numerical analysis, Confining pressure, Regression

In this paper, a strategy to simultaneously improve the response speed, selectivity and photosensitivity of ultraviolet photodetector is presented. Metal-semiconductor-metal ultraviolet photodetectors based on Zinc oxide nanorods are designed and fabricated. The ZnO nanorods of detectors have been synthesized by chemical bath deposition method in four different solvents of growth precursors (including pure deionized water and the solvent containing Methanol, Ethanol or Isopropanol and Deionized water). The optimal condition of synthesizing ZnO nanorods in the chemical bath deposition method is a temperature of 90 ℃ and 2.5 h of the growth process. The morphological, optical and electrical impact of OH source supplementary by adding alcohol on ZnO nanorod-based detector are investigated. The results indicate the supplement of alcohol to the precursor make the growth nanorods be more mono-crystalline and highly vertical. Nanorods growing in the Isopropanol are denser, longer and thinner. Moreover, the greater the concentration of OH ions in the growth precursor, the greater the selectivity of the photodetector is. Furthermore, the illumination-to-dark current ratio enhances from 2 orders of magnitude for pure deionized water solvent to 4 orders of magnitude for Isopropanol containing precursor. The results reveal the increase in the density of nanorods of the photodetector declines the dark current. In addition, the photosensitivity of the detector prepared in Isopropanol containing precursor is about 1.99 × 105 which is the highest sensitivity in comparison with the other detectors. The results of the transient response of photodetectors indicate the fastest response and recovery time are 12 s and 36 s, respectively, which belong to the Isopropanol containing precursor-based photodetector. Consequently, the ZnO nanorod-based photodetector with Isopropanol alcohol containing precursor makes precise detector due to its greater selectivity, greater photosensitivity, faster response and recovery time and lower power consumption.

The aim of this study was to investigate the effect of magnesium oxide nanoparticles (MgO NPs) and MgO NPs coated with glucose (MONPCG) on Leishmania (L) major. First, the promastigotes of L. major were separately incubated with serial concentrations of MgO NPs and MONPCG for 24, 48, and 72 h at 37 °C. Then, the cell viability of promastigotes was evaluated by MTT assay. On the other hand, the relative expression of Cpb and GP63 genes was detected by quantitative-real time PCR. Based on results, the increase of concentration, both MgO NPs and MONPCG, and incubation time led to decrease of cell viability. Moreover, the expression of Cpb and GP63 genes was decreased with increase of concentration of MgO NPs and MONPCG. Also, the increase of incubation time led to decrease of their expression in MgO NPs treated promastogotes. But, in case of MONPCG treated promastogotes, the increase of incubation time did not change the expression of Cpb and GP63. Interestingly, MONPCG could silence Cpb and GP63 genes better than MgO NPs. Note, the capability was also seen at sub-toxic concentrations of MONPCG.

Powder coating nanocomposite with antibacterial properties is the aim of this study. For this purpose, nano zinc oxide was modified by vinyltrimethoxysilane (VTMS) and Triethoxy(methyl)silane (TEMS). Then various percentages of modified and non-modified nano ZnO (1, 3 and 5%), polyester resin and triglycidyl isocyanurate as a hardener were blended by twin screw extruder. Prepared polymer–matrix composite (PMC) was atomized and coated by electrostatic method on aluminum plates. Finally, samples were cured for 10 min at 200 °C. For investigating the thermal stabilities of modified nano particles, thermogravimetric analyses (TGA) were used. Antibacterial properties of coatings were investigated by gram negative bacteria Escherichia coli and gram positive Staphylococcus aureus. The results showed that the coatings demonstrate significant antibacterial activity by increasing amounts of ZnO nanoparticles (5%) when were modified by VTMS.

In this study, we used an approach to check the Hemagglutinin antigen–antibodies interactions after fusion of one or two gene segments to Hemagglutinin gene in some influenza DNA vaccines. We designed different DNA vaccine constructs containing Hemagglutinin 9 (H9) gene fused to four or eight 29 amino acids of C3d (4/8P29C3d) and/or 3, 4 domains of the Fc part of IgY (FcIgY) coding sequences. As there are receptors for P29C3d and FcIgY on the immune cells, fused H9 are targeted to these cells. Three dimensional (3D) structures of the DNA vaccine coded proteins were modeled and docked with two antibodies (1KEN, 1QFU) to evaluate the effect of the H9 gene fusion to the other gene segments (4, 8 P29C3d and FcIgY) on the interaction of two H9 spatial epitopes. Also, we docked DNA vaccine proteins containing Fc IgY to its receptor (CHIR AB1) and compare interaction affinity of Fc IgY alone with affinity of DNA vaccines containing Fc IgY. The average of 1KEN and 1QFU interface scores were 94.89 and 93.09% of H9 DNA vaccine–antibodies interface scores, respectively. These percentages showed a little change in the H9 immunogenic parts. Also, because of spatial freedom of H9 part in all DNA vaccine proteins, added parts may not interfere with antibody–antigen interactions. Once, H9+FcIgY and CHIR AB1 affinity decreased in comparison with affinity of Fc IgY alone and CHIR AB1, affinity of H9+8P29C3d+FcIgY and CHIR AB1 increased to 132%. So, this would be expectable that despite of loss of affinity in H9 and its antibodies in the H9+8P29C3d+FcIgY, dramatic increase of Fc IgY and CHIR AB1 affinity in this group, could repair the loss of H9 affinity and may lead to a better immunogenicity.

In this work various morphologies of tin dioxide nanostructures were synthesized via chemical reaction between tin chloride and different capping agents. The effect of different parameters such as precursors and temperature on the morphology of SnO2 nanostructures was investigated. Photo-catalytic property of tin oxide was examined by degradation of methyl orange as organic pollutant in water under UV light irradiation. Nanostructures were characterized by X-ray diffraction, photo luminescence, Fourier transform infra-red, diffuse reflectance spectroscopy, scanning electron microscopy and transmission electron microscopy. For preparation of nanocomposite tin dioxide was added to poly carbonate and poly styrene and results show that the SnO2 nanostructure can improve both thermal stability and flame retardant property of the polymeric matrixes. The enhancement is due to suitable dispersion and compatibility between polymeric chains and inorganic additive.

In this work, germanium dioxide nanostructures were prepared by a facile co-precipitation method. In this synthesis approach was used from acetyl acetone as capping agent to get the smallest nanoparticles. Some of effective parameters were optimized to achieve the best morphology of product, such as mole ratio of acetyl acetone, temperature and time. Small germania nanostructures with a size about 70 nm sizes were achieved in this method. Nanostructures were characterized using X-ray diffraction, scanning electron microscopy, transmission electron microscopy, Fourier transform infrared techniques X-ray energy dispersive spectroscopy and ultraviolet spectroscopy (UV–Vis). Various properties such as photoluminescence, photocatalytic and photovoltaic property were studied for as-prepared nanostructures. Results of germania nanostructures show that product revealed a PL band that caused from recombination of electron and hole in nanostructure. On the other hand, these nanostructures show a good photocatalytic behavior for degradation of methyl orange in presence of UV light. Therefore germania nanoparticles applied in photovoltaic measurement.

Different morphologies of tin(IV) oxide nanostructures were synthesized via a simple chemical reaction in solvent of water. The effect of various precipitation agents (alkaline) on the particle size of the products was investigated. Photo-catalytic property of SnO2 in degradation four different dyes as organic pollutants in water was examined under ultraviolet–visible irradiation. Nanostructures were characterized by X-ray diffraction pattern, scanning electron microscopy, transmission electron microscopy, Fourier transform infra-red, photoluminescence, diffuse reflectance spectroscopy and energy dispersive spectroscopy. For preparation of nanocomposite, tin dioxide was added to poly vinyl alcohol and results show that SnO2 nanostructures can improve thermal stability and flame retardant property of the polymeric matrix.

In this work, a facile Pechini sol–gel method was used from to prepare gemania nanoparticles for the first time. Different effective parameters on morphology and purity of product were optimized to achieve the best product. These parameters included the mole ratio of acid to solvent, temperature and type of organic acid. Nanoparticles were characterized using X-ray diffraction, scanning electron microscopy), transmission electron microscopy, Fourier transform infrared techniques X-ray energy dispersive spectroscopy and Ultraviolet spectroscopy (UV–vis). The photoluminescence, photocatalytic and photovoltaic properties of product were studied for as-prepared Germania. Results show that a PL band was represented by Germania nanostructures. These PL band caused from recombination of electron and hole in Germania nanostructures. Therefore these nanostructures are suitable for application in photonic devices. On the other hands these nanostructures show a good photocatalytic behavior for degradation of Methyl Orange as an azo organic pollution in presence of UV light. Germania nanoparticles could be applied in photovoltaic measurement. As-prepared nanomaterials show photovoltaic behavior in presence of metal free dye (EY).

The combustion synthesis of elemental Mo nanoparticles by zincothermic reduction of MoO3 was investigated in this research. It was determined that MoO3 reduces to Mo by means of two sub-reactions. The results showed that MoO3 reduces initially to MoO2 and subsequently dioxide phase reduces to elemental Mo. Due to the formation of MoO2 during the combustion moment, a considerable amount of unwanted Zn2Mo3O8 (2ZnO·3MoO2) phase was synthesized. Since the presence of this phase would prevent the reduction to be completed, hence this article was devoted to introduce some ways by which the zincothermic reduction of MoO3 can be completed. In one approach, the results indicated that by increasing the microwave heating duration after combustion moment, the unwanted Zn2Mo3O8 compound reduced successfully to Mo. In the other approach, the use of over-stoichiometric amounts of Zn led to prevent the formation of the undesired phase. In this research, X-ray diffraction technique (XRD), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS) were used to characterize the products of the reactions.

In this paper, the effect of different gate materials, including Metal, p-type and n-type silicon, on electrical characteristics of zinc oxide nanowire field effect transistors (FETs) is studied with TCAD software. To analyze the ZnO NWFET performance, I–V characteristic, electron mobility and threshold voltage are investigated and compared. Comparing results indicates, p-type silicon gate ZnO NWFET has proper output performance with a threshold voltage of 0.75V, on/off current ratio of ∼109 and electron mobility of ∼96 cm2/V. s in the transistor channel. This device is then used for multi-channel FETs in order to raise FETs drain current. Simulation results show the current is multiplied by six in using three channel FET. This device can be used for applications which need a high current response and high current on/off ratio.

Background Propolis is one of the most potent natural antibiotics. Propolis as an active natural substance is attractive due to its antimicrobial properties. Propolis has been used in folk medicine for centuries. It is known that propolis possesses anti- microbial, antioxidative, anti-ulcer and anti-tumor activities. Therefore, propolis has attracted much attention in recent years as a useful or potential substance used in medicine. Objectives The purpose of this study was to verify the activity of an oily liquid extract of propolis that called propolis extract in oil against some Gram-positive and Gram-negative bacteria. Methods In this experimental study antimicrobial activity of oily liquid extract of propolis called propolis extract in oil with different concentration of ethanol, methanol and dimethyl sulfoxide as diluents against different bacteria species. The duration of study set up was from Nov 2014 to Sep 2015. Chi-Square and Kappa methods, using Open Epi and Graph Pad Prism Software (Graph Pad, San Diego, California, USA). Graphs were plotted by Microsoft Excel software. Results In the agar diffusion tests, using wells containing propolis suspension with methanol / dimethyl sulfoxide / ethanol per wells, the some of bacteria were most sensitive to the effect of propolis preparations. No growth inhibition zone was shown in the agar diffusion test with paper disks impregnate with methanol/ dimethyl sulfoxide suspension. Conclusions The evaluation of the examination results showed that the effectiveness of the extract against bacteria may be explained by the fact that the effect of oily propolis was statistically significant by the introduction of methanol and dimethyl sulfoxide.

Background The genus Nocardia is Gram-positive, aerobic filamentous bacilli and saprophytic micro-organisms that can be isolated from freshwater, salt water, dust and decaying vegetation especially the soil. This study aimed to investigate the several media for to determine a suitable culture media with the ability to better for the isolation of Nocardia from soil. Methods In this study, 400 soil samples were collected from different areas from Iran. The soil samples were then cultured on the four culture media such as Humic acid vitamin B agar, Paraffin agar, Sabouraud dextrose agar supplemented whit cycloheximide and carbon-free broth containing paraffin rods and incubated at 35°C. All of culture media investigated every 3 days for a month. Colonies suspicious to Nocardia were stained with Gram-stain, acid-fast and partially acid-fast and evaluated for resistance to lysozyme. Results From 400 soil samples, the number of 62, 10, 28 and 19 strains of Nocardia were isolated by paraffin rods, Humic Acid Vitamin B agar, Paraffin agar and Sabouraud dextrose agar whit cycloheximide, respectively. Most Nocardia strains were isolated using paraffin bait technique. Conclusions Isolation of Nocardia spp. is enhanced by using the paraffin baiting technique that relies on the selective ability of this micro-organism to metabolize paraffin.

It has been shown earlier that formation of undesirable W2C phase during mechanochemical synthesis of WC–Al2O3 composites from WO3–Al–C mixture is due to high temperatures caused by the large heat release during the initial aluminothermic reduction of WO3. With the aim of preventing the formation of W2C, in this study, Al2O3 was added to lower the reaction temperature. Thermodynamic calculations showed that Al2O3 presence in WO3/2Al/C/xAl2O3 mixtures would lower the adiabatic temperature. Experimental findings revealed that with no Al2O3 addition, released heat in the mixture activates carbothermic reduction of WO3 and causes carbon deficiency, which results in W2C formation. When x = 0·6, although product consists of W2C phase, the coolant effect of alumina diminishes carbon deficiency phenomenon with a consequence of more WC formation. For the WO3/2Al/C/1·2Al2O3 mixture, carbothermic reduction reaction was prevented, which brings about complete conversion of W to WC after milling. The TEM observ...

Possibility of synthesis of tungsten carbide–alumina composite powder from WO3–Al–C mixture via microwave-assisted SHS process in a domestic microwave oven has been investigated. By comparison of the results of thermodynamic calculations with experimental findings, it was found that during microwave heating of WO3:2Al:C mixture, synthesis process initiates by vigorous exothermic reaction of WO3 with Al which results in a great deal of heat. Major portion of tungsten carbide phase in the product is W2C, whose formation is supposed to be related to the high thermodynamic stability of this compound at high temperatures. W2C formation could also be related to carbon loss phenomenon in the mixture, as a consequence of some carbon burn. It has been concluded that addition of excess carbon to the initial mixture together with extension of the microwave processing time, increase the amount of WC phase in the product in expense of W2C. Experimental results showed that only small amounts of W2C remain in the product with around 80 mol% excess initial carbon and about 10 min of microwave heating time.