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Aims: Reports show that vaccination against influenza could elicit nonspecific immune reactions against coronavirus disease-19 (COVID-19). The present research aimed to evaluate the prevalence of COVID-19 disease among the staff of Shahid Beheshti hospital in Kashan despite vaccination against influenza.
Materials & Methods: This study was performed on 1400 employees of Shahid Beheshti hospital in Kashan from February to August 2020. Personnel whose disease was confirmed by PCR test or CT scan were considered to have COVID-19. In the present research, the relationship between influenza vaccination and the incidence of COVID-19 infection was evaluated. The collected data were analyzed by SPSS software Version 26.
Findings: Out of a total of 1400 hospital personnel participating in this study, 272 people were diagnosed as COVID-19. Among 272 patients, 23 (8.45%) cases were vaccinated. The average age of vaccinated patients was 33.48 ± 12.72 years, of whom 14 (60.87%) patients were female. Vaccination was significantly associated with prevention of COVID-19 infection (p< .05). The study of odds ratio (OR) to evaluate the effect of vaccination showed that the OR was 0.61 (95% CI: 0.39- 0.97). There was a significant difference in SpO₂, type of treatment, and lung involvement based on CT between the two groups of vaccinated and unvaccinated COVID-19 patients (p< .05).
Conclusion: In vaccinated group, COVID-19 was lower than of the no influenza vaccinated group. According to the results, the use of influenza vaccine as an effective vaccine against the new coronavirus strains could be helpful in controlling the disease.

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Iran is one of the most important fig producer countries around the world. Intermediate moisture fig is a processed product. One problem about intermediate moisture fig is that the color will be changed and transmute to brown during storage after processing. The purpose of this research was to study soaking temperature and time effects and to evaluate the effects of calcium chloride, cysteine, sodium metabisulphite and citric acid in various concentrations on prevention of semi-moisture fig browning at room temperature. Chemical compounds (protein, total sugar, fat, fiber and moisture) of fig samples were determined. In order to prepare product five different periods of time(3, 6, 9, 12, 15 min) and five different degrees of temperature (20, 40, 60, 80, 100°C) based on central composite rotational design were used. Samples were kept in room temperature for 2 weeks to evaluate the effects of soaking parameters on color and texture of product. After that moisture, color and texture of samples were determined. First different solution of calcium chloride (0.6, 1, 1.5, 2% w/w), citric acid (0.5, 1, 2, 3%w/w), cysteine (0.05, 0.07, 0.2, 0.5%w/w) and sodium metabisulphite (500, 800, 1000 and 1200 ppm ) were prepared. Dried figs were dipped in prepared solutions and water was used to evaluate control samples to optimize the time and temperature, then color of the samples were measured in specific period of time during four months. Results showed that temperature of 60°C and 3min interval provided 20% moisture in the product which assessed as the best moisture content for preserving color and texture. The most desirable L value was obtained using citric acid (1, 2, 3%w/w) and Calcium chloride (1.5%w/w). However sodium metabisulphite and cysteine in concentration of 0.07%, 0.05%, 0.2% showed significant difference with control, the results were not satisfactory. Results showed that using suitable temperature in rehydration of fig to inactivate poly phenol oxidase and chemical treatments to postpone and reduce the browning reaction rate were effective.    

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  Rheological study of date syrup, date concentrate and date liquid sugar can improve their industrial applications specially for sugar (sucrose) substitution. In this research the rheological behavor of date syrup, date concentrate, date liquid sugar and sucrose solutions was investigated using a Brookfield Viscometer at 50, 55, 60 and 65 °Brix, 25 °C and shear rate of 80-480 s^-1 .The variables were product type and concentration. Moreover, for textural evaluation a texture analyser was used to examine date syrup, date concentrate and date liquid sugar at 50, 60 and 70 °Brix. The results showed that the Power law model was suitable to the rheological behavior of all samples and all concentrations. In date syrup by increasing concentration from 50 to 65 °Brix, consistency coefficient (K) increased, flow behavior index (n) decreased and the sample became more shear thinning. However, all other samples were Newtonian. Therefore a similar flow type behavior for these three samples is expected in food processings. Among all tested concentrations, the date syrup sample with a Brix of 65 had the highest consistency coefficients.  This indcates using date syroup in food formulations, usage level of hydrocolloids can be reduced. These findings were confirmed by texture data.

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In recent years, many advances have been made in improving the biocatalytic activities of enzymes. Interaction of enzymes and macromolecules have important role in stabilization of enzyme’s structure and function. Lysozyme lyses the bacterial cell wall by splitting ß (1–4) linkages between N-acetylmuramic acid and N-acetylglucosamine of the peptidoglycan in bacterial cell walls. Tragacanth is a polysaccharide obtained from exudates of the species of Astragalus. It is a very complex heterogeneous anionic polysaccharide of high molecular weight. Tragacanth consists of two main fractions: a water-insoluble component called bassorin, and a water-soluble component called tragacanthin. The aim of this investigation was to attach tragacanthin (water-soluble component of tragacanth) to lysozyme by Maillard reaction. The covalent attachment of this hydrocolloid with lysozyme was confirmed by SDS-PAGE and ion exchange chromatography. The conjugates exhibited improved solubility, foaming and emulsion properties. In addition, thermal stability of lysozyme in this conjugate was increased significantly. According to these results, attachment of lysozyme to tragacanthin can increase the application of this hydrocolloid as a functional component and lysozyme as a natural antimicrobial component in food and pharmaceutical industry.

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Snacks are amongst popular foods, therefore improving the quality of the snacks is of great importance. Half-products are a kind of cereal based snacks that are sold in the form of dried pellets and then deep-fried for a few minutes by the consumer to form puffed crispy edible snacks. The main aim of this study was to determine the sufficient pellet moisture content in order to reach an appropriate snack quality.  Pellets were produced using a single screw extruder by mixing wheat flour and starch to reach moisture content of 7.5%. The moisture content of the pellets was then adjusted on 5, 10, 12, 14 and 16%. Pellets were deep-fried at 185 °C to reach their maximum volume and then their physical and sensory characteristics were studied. Increasing the moisture content from 5 to 16% reduced the density, increased lightness, reduced redness and yellowness of the snacks. The fracture force to break of snacks reduced with increasing the moisture up to 10% but it reduced with further increase in pellet moisture content. Increasing pellet moisture up to 14% improved the sensory characteristics of the snacks while further increase in the moisture content reduced these properties. Adjustment of the pellet moisture content is a practical solution in the industry to improve the quality of the snacks. The most appropriate moisture content of the pellet was in the range of 10-12%. At higher or lower moisture levels, the sensory characteristics of product were affected, negatively.

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The main purpose of this study was to use wheat germ in production of milk dessert. Therefore, wheat germ was first heated at 150 °C for 15 min, then milled to obtain particle sizes of 125, 210 and 354 micrometers. Samples were made with 10% sugar, 2% gelatin and 88% low-fat milk (1.5% fat) and different levels of wheat germ (2.5, 5, 7.5 and 10%, w/w). Different characteristics of the fresh product and after storage for 15 days at 4 °C were determined. The results showed that with increasing the amount of wheat germ, dry materials of the samples increased while the pH decreased. Changes in the particle size of the samples had no effect on the dry materials. Textural evaluations showed that with increasing the germ level, particle size and storage time, hardness, cohesiveness, chewiness and gumminess, increased while elasticity decreased. Studying the internal structure of the desserts using scanning electron microscopy showed that the uniformity of the samples increased with increasing the germ content in dessert formulation. Moreover, with increasing the percentage and particle size of the germ, the darkness, redness and yellowness of the desserts increased. The results showed that the syneresis of desserts reduced with increasing the level of the germ, however, changes in particle size of the germ had no effect on this parameter. Sensory evaluation results concluded that the samples were prepared with maximum amount of 7.5% germ with particle size of 125 micrometer were the most acceptable samples.

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In biscuit production, sucrose is one of the major ingredients. Addition of sucrose is not only for the sweet taste it provides, but also for its positive effects on physical properties of the product. Since sucrose consumption is growing worldwide, finding an alternative sugar source other than sugar beet and sugar cane as the main sources of sucrose is necessary. In this research, sucrose was replaced with 0, 20, 40, 60, 80 and 100% (weight basis) of date syrup and date liquid sugar and the effects on rheological properties of biscuit dough were studied. The results from farinograph showed that the dough consistency and elasticity reduced with increasing the sucrose replacement level. However, no significant difference between the samples made with date liquid sugar and date syrup was not observed. The results of Texture Analyser showed that with reducing the sucrose content dough consistency, energy required for compression, springiness and cohesiveness reduced while adhesiveness increased. The values obtained for energy, consistency and adhesiveness of the samples containing date liquid sugar were higher than those of date syrup, while springiness was lower.  Based on the results the maximum percentage of the sucrose replacement with date liquid sugar was 60% and with date syrup was 40%. At higher percentages the quality of the dough reduced considerably.   

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Plasma assisted machining (PAM) is a method to improve machinability of hard turning. The process of plasma assisted machining for turning applications utilizes a high-temperature plasma arc to provide a controlled source of localized heat, which softens only that small portion of the work material removed by the cutting tool. The goal of this study is to present a methodology for determination cutting force during plasma enhanced turning of hardened steel AISI 4140. In this regard, a finite differential model was made to estimate the uncut chip temperature under different plasma currents, cutting speeds and feeds during PAM. A mechanistic model developed to estimate cutting force under different PAM conditions by considering shear stresses in the primary, secondary shear zones and force on the tool edge. The proposed model was calibrated with experimental hard turning data, and further validated over practical PAM conditions. Mean errors of predicted values and experimental data is lower than 10 percent. It is shown that PAM can decrease main cutting force in comparison to convectional to 40 percent in turning of hardened steel at high levels of uncut chip temperature due to softening the material.

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Ultrasonic Assisted Magnetic Abrasive Finishing (UAMAF) is the combination of magnetic abrasive finishing (MAF) and ultrasonic vibrations to finish the surfaces in nanometer scale. In this work, the experimental setup for UAMAF was prepared to finish inner surface of tube workpiec. By using experimental setup, the effect of experimental parameters such as ultrasonic vibrations, mesh number, the type of abrasives (SiC and diamond) and finishing time has been investigated on the changes in the surface roughness of AL6061 tube workpiece. The experimental results showed that the use of ultrasonic vibrations has a significant effect on reducing the surface roughness. The changes in surface roughness increases with the mesh number from 90 to 800 and finishing time from 30s to 5 min. Among two types of abrasives, diamond showed the best performance in finishing. Optical microscopy images showed that the dominant finishing mechanism in MAF for coarse grains (with mesh size of 90 and 120) is two body and for fine grains (with mesh size of 220, 400 and 800) is three body. In UAMAF for both of the coarse and fine grains the dominant finishing mechanism is three body.

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Date press cake is a by-product of date fruit juicing that has remained underutilized in the food industry. This is mostly due to the lack of information and technical knowledge about its chemical composition, nutritional value, health benefits and possible effects on the quality of food products upon inclusion. The main aim of this research was to determine the chemical composition, bioactive compounds and functional properties of date press cake to promote its food applications as an economical and available functional ingredient. The research was carried out on ground date press cake obtained from Shahani dates with two particle sizes of 355 µm (coarse) and 167 µm (fine). On average, Shahani date press cake contained 13.37% moisture, 4.92% fat, 6.35% protein, 11.74% crude fiber and 79.06% carbohydrate. Fructose was the main simple sugar, magnesium was the major mineral, oleic acid was the predominant fatty acid, and phenolic compounds were the main antioxidant. The chemical composition and functional properties of the date press cake were affected by its particle size. The coarse sample had lower fibre, oleic acid, total phenolic and flavonoid content and antioxidant activity than the fine sample. However, the fine sample had higher sugar and fat content and exhibited higher water holding capacity and solubility than the coarse sample.
 

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Metal and especially aluminum mirrors have wide applications in the optical industry due to their desirable properties, hence requiring very high polished surfaces. One of the methods of preparing aluminum mirrors is single-point diamond turning. In this research, the manufacturing process of 6061-grade aluminum mirrors has been studied using diamond turning and consequent polishing process in order to reach surfaces with acceptable optical properties. In the first part, the effective range of turning parameters was determined. The results showed that the feed values less than 5 µm/rev, the cutting-edge radius between 0.2 and 0.8 mm, and the rotational speed of 2250 rpm have a greater effect on the surface roughness. In the second part of the research, initially, the turning process was performed with effective parameters and then the polishing process was applied as the final finishing process. Surface finish is evaluated by surface roughness and surface interferometry parameters. The results showed that the smaller surface roughness after the diamond tool turning process led to higher optical properties after the final polishing process. The lowest PV value equal to 0.293 µm was obtained by diamond turning with 3 µm/rev and a cutting-edge radius of 0.8 mm.
 

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Metal and especially aluminum mirrors have wide applications in the optical industry due to their desirable properties, hence requiring very high polished surfaces. One of the methods of preparing aluminum mirrors is single-point diamond turning. In this research, the manufacturing process of 6061-grade aluminum mirrors has been studied using diamond turning and consequent polishing process in order to reach surfaces with acceptable optical properties. In the first part, the effective range of turning parameters was determined. The results showed that the feed values less than 5 µm/rev, the cutting edge radius between 0.2 and 0.8 mm, and the rotational speed of 2250 rpm have a greater effect on the surface roughness. In the second part of the research, initially, the turning process was performed with effective parameters and then the polishing process was applied as the final finishing process. Surface finish is evaluated by surface roughness and surface interferometry parameters. The results showed that the smaller surface roughness after the diamond tool turning process led to higher optical properties after the final polishing process. The lowest PV value equal to 0.293 µm was obtained by diamond turning with 1.5 µm/rev and a cutting edge radius of 0.8 mm.