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Metformin enhances insulin's effect and increases cells’ sensitivity to insulin. In this paper, nanocomposite was designed and used in the metformin release system, which was able to release the required drug in a controlled manner. In this research, nanoparticles of zinc oxide (ZnO) were prepared via the sol-gel method. The experimental design central composite response surface method was applied for the optimization of the nanoparticles based on varied variables such as the weight of zinc acetate (gr) (X ₁) and the volume of triethanolamine (ml) (X₂). The particle size of the optimized nanoparticle was reported to be 28 ± 21.27 nm; zeta potential and PdI were 25.54 ± 1.64 mV, 0.168 ± 0.05 respectively. The chitosan polymer was used to improve environmental compatibility and increase drug release control; finally, metformin was loaded on the optimized nanocomposite. Structural properties were analyzed using scanning electron microscopy (SEM) X-Ray Diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), and Dynamic Light Scattering (DLS). The SEM images showed that the average nanocomposite size was 40 nm. The results of XRD patterns and SEM images were also consistent with each other and the average particle size was the same. Infrared spectrophotometry showed the presence of chitosan used to coat nanoparticles on their surfaces and confirmed the loading of metformin. An in-vitro metformin release from the nanocomposite was conducted in PBS (pH=7.4) and analyzed by a spectrophotometer at 233 nm. Metformin has a high solubility in water, and since it is difficult to prepare a slow release form of high-solubility drugs, the aim of this study was to design a slow-release formulation of metformin with a suitable profile that could control release without explosive release for up to 120 hours.

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Gas sensitive metal oxide layers used in fabrication of resistive gas sensors are prepared by different deposition techniques. The technical data reported on some basic and practically important specifications of these devices, although fabricated based on the same gas sensitive oxide, are anomalously different. The influence of the fabrication technique used for the deposition of the gas sensitive layer on determination of the significant specifications of the transient response of a resistive gas sensor is experimentally investigated for the first time. ZnO and SnO2 layers were prepared by LPCVD, PVD, EPD and powder pressing techniques. Prototype gas sensors based on these layers were fabricated. The transient responses of these devices to a step change in the composition of the surrounding atmosphere were recorded and compared. It was shown that the thickness, porosity and pore micro-structure of the gas sensitive layer are the most effective parameters in determination of the transient response. The relationship between these parameters and the temporal variation of the electrical conductivity of the gas sensitive layer was qualitatively analyzed. Oxide layers of higher porosity resulted in gas sensors of faster response, but response time increased with the thickness of these gas sensitive layers. The sensors produced by EPD technique demonstrated the fastest responses while those produced by CVD were the slowest among the samples investigated.

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Aims: Essential oils are a complex of volatile compounds obtained from different parts of plants. Cinnamon (Cinnamomum zeylanicum) essential oil (EO) is known as a suitable source of antibacterial compounds. The aim of present study was to investigate the antibacterial activity of cinnamon EO and ZnO nanoparticles (NPs) against 2 strains of Listeria monocytogenes.
Materials & Methods: In this experimental study, 2 strains of L. monocytogenes (a standard strain and a fish isolated strain) were used. The antibacterial activity of cinnamon EO and ZnO NPs was assessed by well diffusion test. The minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) of cinnamon EO and ZnO NPs were also determined using broth macrodilution method.  Moreover, the antibacterial properties of cinnamon EO and ZnO NPs were investigated in a liquid medium. The data were analyzed by SPSS 19 software, using one-way ANOVA and Tukey's post hoc tests.
Findings: The Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) of cinnamon EO were 16µl/ml and 64µl/ml, respectively. Furthermore, the MIC and MBC of ZnO NPs were 12.5mg/ml and 25mg/ml, respectively. The bacterial population significantly decreased with increasing the ZnO NPs and the cinnamon EO concentrations (p<0.05) and during cold storage, there were significant differences between the 2 strains.
Conclusion: Cinnamon essential oil and ZnO nanoparticles have strong antimicrobial effects against L. monocytogenes, so that the cinnamon essential oil shows bacteriostatic effects on Listeria, but ZnO nanoparticles show bactericidal effect.

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Backgrounds: Uropathogenic Escherichia coli is one of the most important etiological agents of UTI. The aim of this study was to investigate the antibacterial effects of zinc oxide nanoparticles (ZnONPs) on aminoglycoside-resistant E. coli isolates from patients with UTI.
Materials & Methods: After identifying E. coli strains in 100 out of 250 urine samples, antibiotic susceptibility was evaluated against six antibiotic classes (with emphasis on aminoglycosides) by disk diffusion method according to CLSI-2020 guidelines. The presence of aac (6')-Ie-aph (2'') gene in isolates was investigated by PCR. Antibacterial properties and minimum inhibitory concentration (MIC) of zinc oxide nanoparticles were evaluated by agar well diffusion and broth microdilution assays, respectively.
Findings: Among 100 E. coli isolates, the highest and lowest antibiotic resistance rates were observed against tetracycline (70%) and ofloxacin (10%), respectively. Of 30 gentamicin-resistant E. coli isolates, 17 (56.5%) isolates harbored the aac (6')-Ie-aph (2'') gene. In agar well diffusion assay, 22 (74%) gentamicin-resistant isolates were eliminated by zinc oxide nanoparticles at a concentration of 150 mg/L, while ZnONPs at 300 mg/L could eliminate all gentamicin-resistant isolates. Furthermore, ZnONPs could inhibit all bacteria at a concentration of 200 μg/mL (MIC₉₀ ≥ 100).
Conclusion: Spread of the aac(6')-Ie-aph(2'') gene could increase gentamicin resistance among E. coli strains causing UTI. Given the favorable antibacterial effects of zinc oxide nanoparticles in vitro, the clinical application of these nanoparticles in the treatment of UTIs caused by multidrug-resistant E. coli could be investigated in future studies.
 

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Aims: The present study intends to assess the toxicity of CuO and ZnO nanoparticles (NPs) at laboratory conditions on some pathogenic bacteria for the reared fish, as well as, a bioassay on rainbow trout.
Material & Methods: For this purpose, the sensitivity of them to the mentioned NPs with a reference antibiotic (florfenicol) was assayed through the well diffusion method, as well as, minimum inhibitory concentration (MIC) and minimum bacteriocidal concentration (MBC) were determined by microdilution technique. On the other hand, the lethal toxicity test has been accomplished to the calculation of median lethal concentration (LC50) on some rainbow trout (55.3±7.6 g) in static condition for the 96 consecutive hours. We use one-way ANOVA and Probit regression in order to data analysis.
Findings: Results show that NPs of copper oxide and zinc oxide could significantly inhibit the growth of Streptococcus iniae or kill it at 0.18 and 0.24 µg/ml and more, respectively. The comparison between LC50-96h quantities of CuO NP (107.4 µg/l) and ZnO NP (102.3 µg/l) indicated that the CuO NP has more toxic potential.
Conclusion: According to the laboratory findings, the susceptibility of S. iniae and L. garvieae to ZnO NP were close to florfenicol. The mortality in the fish species due to lethal toxicity would occur if the effective concentration of NPs on the bacterial pathogenic agents being used directly.

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Double layer ZnO/SnO2 thin film resistive gas sensors were fabricated by successive PVD of those oxides onto porcelain substrates. The metallic contacts were provided by electron beam evaporation of platinum onto substrates prior to deposition of the gas sensitive layers. Deposits were thermally annealed at different temperatures. It was shown that the activation energy of electrical conduction in the double layer depends on the annealing temperature. Higher annealing temperatures result in larger activation energies. The sensitivity of the double layer devices to ethanol vapor was measured and compared to that of single layer SnO2 sensors fabricated at similar conditions. It was shown for the first time that the gas sensitivity of ZnO/SnO2 thin film gas sensors can be adjusted by controlling parameters of the thermal annealing process.

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In this study, 50 Staphylococcus aureus samples from Baghdad Hospital were collected and examined, 17 samples were infected with methicillin-resistant Staphylococcus aureus (MRSA) and 5 samples were infected with vancomycin-resistant Staphylococcus aureus (VRSA). The sensitivity of the isolates against different antimicrobial agents was evaluated using the VITEK2 standard system. According to CLSI, the minimum inhibitory concentration (MIC) values of zinc oxide quantum dots (ZnO-QDs) were also tested by the Muller-Hinton dilution method. In addition, polymerase chain reaction (PCR) was performed to identify vanA and mecA genes. The antibacterial effects of ZnO-QDs on VRSA were higher than MRSA isolates.
 

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Economic and industrial growth of the recent decades in most countries and the changing pattern of life, cause a dramatic increase in the production of industrial and urban waste. Considering population growth and economic, cultural and industrial changes, it`s necessary to have a proper management plan to prevent environmental damage and save the cost of waste management. One of the issues associated with urban waste management is controlling and treatment of leachate. Leachate treatments methods are classified into three groups include: leachate transmission; biodegradation techniques and physiochemical treatment methods. Due to its reliability, simplicity and high cost-effectiveness, biological processes are the most conventional methods in leachate treatments. However, due to high organic load and presence of refractory contaminants in leachate, biological treatment alone cannot remove all of the organic matters from leachate. Therefore, to meet discharge standards, additional treatment is required to remove the remaining materials from biologically treated leachate. Photocatalytic processes have been proven to be an appropriate technology for final treatment of these types of wastes. In this study the capability of UV-ZnO photocatalytic process as a post treatment method for composting leachate was examined at laboratory scale and in batch mode. The effect of some factors such as initial pH, catalyst concentration, light intensity and reaction time on the removal of organic load and color of leachate were investigated. Biological pre-treated leachate samples were collected from the effluent of leachate treatment facility of a composting plant in north of Iran. The leachate samples have been collected in 20 L plastic containers transported to the laboratory and immediately stored in refrigerator at 4˚C to minimize any changes in its physical, chemical, and biological properties until the experiments were carried out. A Plexiglas column with 110 mm inner diameter and 300 mm height were used to conduct experiments. UVC lamps (as the source of irradiation) with different power levels were placed inside a quartz tube (external diameter 0.026m) mounted at the axial centre of the reactor. In each experiment, a specified amount of nano particle was added to leachate into the reactor, at ambient temperature and under a specified amount of UVC radiation. In order to prevent the settling of nano particles, air was continuously injected into the column through a diffuser at the bottom of the reactor. Samples were taken periodically from the reactor for analysis. Prior to analysis, the liquid samples were centrifuged at 3000 rpm for 10 min to remove all suspended particles. In order to prevent reflection and scattering of UV radiation in the environment, the reactor was covered with a thick layer of aluminum foil. Based on the results of experiments, after 120 minutes of radiation with 32 W UVC lamps in pH 11 and in the presence of 1 gr/L of slurry nanoparticles (ZnO), maximum COD and color removal were achieved to be 60% and 68%, respectively. In kinetic studies of batch UV-ZnO photocatalytic process, a pseudo-first order model with reaction rate constant of 0.38 hr-1 was found to fit well (R2= 0.99) with the experimental results.

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In this study, the effect of nanoparticles on oxide at three levels of 1, 3 and 5% was added to polylactic acid and chitosan nanocomposites and the results of its SEM (electron microscope) evaluation were evaluated and showed films containing polylactic acid and chitosan. It had an irregular and compact structure and with the addition of nanoparticles on oxide, it had a regular and cohesive structure. And water vapor permeability showed a significant effect (P <0.05). The results of histometry showed that with increasing the concentration of nanoparticles, the tensile strength of the film and the nanocomposite coating was significantly lower than the control treatment (P <0.05). Also, large changes in length to break point did not show a statistically significant difference. The results of tissue stiffness of this study also showed that during the 15-day storage time, the test treatment had the highest amount of stiffness. The effect of film and coating of nanocomposites based on polylactic acid and chitosan containing nanoparticles on zinc oxide on microbial properties indicated that during the shelf life of bread containing polylactic acid and chitosan dimers has an inhibitory effect on fungal growth by increasing nanoparticles on zinc oxide. Increases significantly. It also showed that the shelf life of seven sliced ​​toast containing the mentioned variables was higher at 5% level compared to the control treatment.
 

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Aim: Zinc oxide nanoparticles are known as important metal oxide nanoparticles and are used in many medical and biological fields, but concerns are rising due to their potential effects on some organs. The aim of this study was to investigate the effect of aerobic exercise on renal angiotensin-II and angiotensin type 1 receptor levels in administered Rats with Nano Zinc Oxide.
Materials and Methods: In this experimental research, 35 male Wistar rats were randomly divided into control, salin, nano zinc oxide, exercise and exercise plus nano zinc oxide groups. Zinc nitric oxide (1mg/kg) was injected intraperitoneally, 5 days a week into exercise and exercise plus nano zinc oxide groups. The exercise program consisted of progressive running on a treadmill (5 sessions per week for 4 weeks). Two days after the last application, the rats were euthanized. The kidney tissue is separated and angiotensin-II and angiotensin type 1 receptor were measured. Data were analyzed by SPSS 20 software using one-way ANOVA and Tukey’s post hoc test.
Findings: After 4 weeks of chronic treatment with nano zinc oxide, the levels of angiotensin-II and angiotensin type 1 were significantly increased. Exercise significantly reduced renal angiotensin II and angiotensin type 1 levels. However, these variable levels in exercise plus nano zinc oxide group still were significantly higher than control group (p<0.05).
Conclusion: Aerobic exercise reduces renal angiotensin II and angiotensin type 1 levels in Administered Rats with nano zinc oxide.

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The purpose of this research was to prepare nanocomposite film based on wheat gluten containing quercetin nanoliposome and zinc oxide nanoparticles and use it to package rainbow salmon; For this purpose, in this research, the effect of quercetin nanoliposome at the levels (0, 5, 10% by volume) and zinc oxide nanoparticles at the levels (0, 3, 6% by weight) using the response surface method in The central composite design template was investigated on the physicochemical properties of the nanocomposite film, and finally, the optimal sample was used in the packaging of rainbow salmon meat to check its properties during the storage period (0, 3 and 6 days). Also, the results of the research on packaged fish meat showed that the use of wheat gluten nanocomposite film containing 10% quercetin nanoliposomes and 6% zinc oxide nanoparticles led to a decrease in peroxide index, volatile nitrogen compounds index, thiobarbituric acid index and total microbial count during the storage period. Became. Also, no significant difference was observed in the fat of the examined samples, and the color of the packaged fish meat was duller than the control sample. Finally, according to the obtained results and investigations, the addition of 10% quercetin nanoliposome and 6% zinc oxide nanoparticles in the wheat gluten nanocomposite film formulation led to the improvement of the properties of the produced film and the properties of the packaged fish during the storage period.
 

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The aim of this study was to investigate the effect of coating grapes by spraying with different concentrations of zinc oxide nanoparticles (0.5 and 1 g/L) both before and after harvest compared to postharvest fumigation of grapes with sulfur dioxide (2.5, 3.5, and 4.5 g sulfur per kg of grapes) on the physicochemical and sensory properties of raisins. The grapes were sun-dried and the resulting physicochemical properties of raisins, such as moisture content, pH, water activity (aw), acidity, free sulfur dioxide, total sulfur dioxide and sensory properties, were evaluated using a factorial design based on a completely randomized statistical model. The results showed that coating with zinc oxide at a concentration of 1 g/L before and after harvest and fumigation with sulfur dioxide after harvest affected the moisture and aw levels of the raisins, with moisture content increasing and aw decreasing compared to the control (p<0.05). No significant differnces was observed in pH of all the raisins coated with zinc oxide as compared to control (3.7) except for the sample coated with 0.5 g/L nano zinc oxide before harvest (3.45). By increasing the sulfur concentrations up to 3.5 and 4.5 g/kg grape, the pH of all the raisins compared to control (3.7), increased (3.8), and decreased (3.45), respectively (p<0.05). Acidity of the all the sulfur-treated samples increased (p<0.05), compared to the control (0.817 %). The concentration of free and total sulfur dioxide was significantly higher in the sulfur-treated samples compared to other treatments and the control (p<0.05). Raisins from grapes coated with 0.5 g/L zinc oxide prior to harvest and raisins treated with 2.5 g/kg sulfur dioxide received the highest overall sensory acceptability ratings from panelists (p<0.05).

 

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The electrical properties of nanostructured piezoelectric materials have attracted the attention of many researchers in the last decade. These features are used in piezoelectric micro-sensors. Mechanical propulsion is usually the result of contact between a piezoelectric surface and a foreign object. In this paper, the effect of mechanical propulsion using an air wave (sound) or vacuum on a silicon diaphragm is investigated. The local stresses created on the diaphragm due to the impact of an air wave have a significant effect on the peak-to-peak voltage of the piezoelectric sensor, which can be measured by measuring changes in this parameter. To investigate this, a micromachined diaphragm of silicon was examined and it was found that fabricating a piezoelectric sensor on a thin and patterned diaphragm could increase the peak-to-peak voltage by about 1.3 times. Detection of these stresses using piezoelectric material layered on the thin and formable diaphragm can act as a piezoelectric microphone or a barometer that the presence of microstructures on the diaphragm will increase their sensitivity.