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Human activin A is a homodimer of βA subunit which is synthesized in the form of prepro-activin with 426 amino acids; mature activin A with 116 amino acids is processed from this larger precursor protein. This protein which was extracted for the first time from follicular fluid is a strong stimulator of FSH biosynthesis. The functions have been found to be exerted by activin, including roles in cell proliferation, differentiation, apoptosis and survival of neurons. As this protein plays a considerable role in the treatment of neurodegenerative disease such as Alzheimer,s disease and wound repair, in this study for the first time was expressed in three different strains of E.coli. Activin A has disulfide bonds in its native and functional structure, so the cytoplasmic reducing environment of E.coli is not appropriate for its expression. Therefore, the oxidative space of periplasm for production of correctly folded activin A was considered. In this study, h-activin A cDNA and modified Iranian Bacillus Licheniformis α-amylase signal peptide obtained from NCBI data bank after codon optimization was cloned in pET21b(+) vector and transformed to BL21(DE3)pLysS, BL21(DE3)Rosetta gami and BL21(DE3) strains of E.coli. Expression occurred via induction of promoter with IPTG. Consequently, extracted proteins from these three strains were compared with each other using SDS-PAGE, Dot blot and western blot techniques. The data shows activin A expression especially in BL21(DE3) and BL21(DE3)Rosetta gami strains of E.coli.

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Purpose: In order to express human granulocyte-macrophage colony stimulating factor (hGM-CSF) under heat shock. Materials and Methods: Two expression plasmids were constructed based on pBC(SK) plasmid. The expression cassettes in the two plasmids are equipped with a 75 base pair fragment, derived from the PL promoter of the bacteriophage lambda (λ). The plasmids also contain a temperature mutant of repressor coding gene (CI857) to regulate the promoter activity. The two plasmids differ from each other in having a transcription termination signal or not, down stream to the recombinant gene in the expression cassette. A pelB signal sequence was also used in order to have the recombinant protein in the periplasmic space of Escherichia coli. The efficiency of the constructed plasmids was demonstrated by heat-regulated expression of hGM-CSF. Results and Discussion: The protein analysis of the recombinant bacteria, containing either of the two plasmids, indicates a successful expression and complete processing of the hGM-CSF precursor, following the heat shock activation of the λPL promoter. In order to enhance the applicability of the terminator containing plasmid, for the expression of other proteins of interest by heat regulation, a multiple cloning site including eleven unique restriction sites was inserted in the plasmids. The heatregulated plasmids, designed in this work, have provided suitable tools to study the expression of recombinant proteins under temperature up-shift in Escherichia coli, when the use of chemical inducers are not desirable.

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The equilibrium moisture content is an important parameter for several post-harvesting operations for pistachio nuts, such as drying processes and storage. In this re-search the adsorption and desorption equilibrium moisture content were determined for two major varieties of Iranian pistachios at 11 to 85 percent relative humidities and a con-stant temperature of 50°C. A significant hysteresis effect between the adsorption and de-sorption processes was observed statistically. For predicting the adsorption and desorp-tion EMC, the Halsey model was found the most proper equation for adsorption processes for two varieties (Ohadi and Kalehghochi), whereas the Oswin and Smith models were most appropriate for Ohadi and Kalehghochi for desorption processes, respectively, at constant a temperature of 50°C.

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Background: Methicillin-resistant staphylococci (MRS) are regarded as a global public health threat. Physicians are restricted in their treatment options due to resistance to aminoglycosides and tetracycline derivatives. This study investigated aminoglycoside and tetracycline derivative resistance among Staphylococcus isolates in Shiraz, southwestern Iran.
Materials & Methods: Totally, 113 staphylococcal isolates were recovered from different clinical samples in Nemazee Teaching Hospital from October 2019 to January 2020. Kirby-Bauer disc diffusion method was performed to assess the antimicrobial susceptibility of the isolates against aminoglycoside and tetracycline antibiotics. Aminoglycoside-modifying enzymes (AMEs) and tet genes were investigated among staphylococci isolates using polymerase chain reactions (PCR).
Findings: MRS prevalence among Staphylococcus isolates was 61% (69 of 113). The majority of MRS isolates were obtained from blood (39.1%; 27 of 69) and urine (17.4%; 12 of 69). The highest prevalence of MRS isolates was among emergency room patients (34.8%; 24 of 69). The highest resistance of MRS isolates was against tobramycin (59.4%; 41 of 69) and tetracycline (55.1%; 38 of 69). The prevalence of tetM and aac (6')-Ie-aph (2'') genes was significantly higher among MRS compared with methicillin-sensitive staphylococci (MSS) (87.5% vs 12.5% and 95.6% vs 6.4%, respectively) (p= .001).
Conclusion: The prevalence of MRS isolates, including methicillin-resistant S. aureus (MRSA) and methicillin-resistant coagulase-negative staphylococci (MRCoNS), was remarkable in Shiraz as the center of medical services in the southwest of Iran. Furthermore, these MRS isolates were highly resistant to aminoglycosides and tetracyclines. Therefore, antimicrobial stewardship is necessary to address health conditions.

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Hyper-glycosylation is an approach to introduce new N-glycosylation consensus sequence(s) (َAsn-Xxx-Ser/Thr three-peptide) into a protein primary amino acid sequences by site-directed mutagenesis which is followed by the attachment of a new glycan to the Asn residue located within the three-peptide sequence. Hyper-glycosylation has attracted lots of interest especially in the protein therapeutics industry. The attached glycan may improve the pharmacokinetic properties of the hyper-glycosylated priteins and increase their half-life in the bloodstream. In the current study, a new N-glycosylation site was introduced into N-terminal Gla domain of hFIX. Arg³⁷ position of mature hFIX was targeted to be converted into Asn residue by site-directed mutagenesis using overlap extension PCR. Recombinant expression plasmids for native and mutant hFIX were constructed. The expression of the recombinant wild-type and mutant hFIX was analyzed in mammalian HEK293 cells using gradient SDS-PAGE and western blotting analysis. The results indicated in higher molecular weight for R37N mutant in compared with the native protein. The glycan attachment to R37N mutant was further confirmed by PNGase digestion and western blotting. 

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Many research studies have been performed on forced convection (active) solar dryers for fruit and vegetables. A short survey of these showed that applying the forced convection solar dryer not only significantly reduced the drying time but also resulted in many improvements in the quality of the dried products. Active indirect and mixed-mode thin layer solar drying experiments were conducted on Sultana grapes. A combination of a solar air heater and a cabinet dryer was designed, constructed and tested for this product in the Agricultural Engineering Department at Shiraz University, Iran. Three air flow rates (0.085, 0.126 and 0.171 m3 s-1) and two types of drying systems (indirect and mixed-mode) were adopted. The south wall of the drying chamber was covered by a sheet of glass for mixed-mode and the glass sheet was covered with a thick sheet of cloth for an indirect solar drying system. Seven well-known thin layer drying models were used separately to fit the mixed-mode and indirect type experimental data for Sultana grapes. For experimental indirect data, the Modified Page model (r= 0.998, χ2= 0.000241) and for experimental mixed-mode data, the Page model (r= 0.999, χ2= 0.000169) showed the best curve fitting results with highest r (correlation coefficient) and lowest χ2 (reduced chi-square) values. The constants in these models explain the effects of drying parameters, air velocity and temperature. To take account of these effects, the best correlation equations between the constants and drying parameters were also introduced using multiple regression analysis.

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A thin layer solar drying method was compared with a traditional method (sun drying) of paddy drying, with their effects on quality characteristics of two varieties of Iranian rice (Kamphiroozi and Sazandegi) studied. Solar drying process was conducted in a passive, mixed mode type solar dryer at about 50ºC for 90 minutes. In sun drying method this process took 8-10 hours at a mean temperature of about 26ºC. Samples were milled and polished. Quality factors including trade quality (head rice yield percent and whiteness), cooking quality (amylose content, gelatinization temperature, gel consistency, aroma and flavor) as well as nutritional quality (thiamine and lysine contents) were evaluated. For a determination of head rice yield, the percentages of de-husked and broken kernels were determined by hand-sorting of broken kernels, the calculation being done through the pertaining formula. Gel consistency was determined according to the method of Cagampang et al. (the consistency of milled rice paste that has been gelatinized by being boiled in dilute alkali and then cooled to room temperature). Amylose content was determined through the simplified assay method of Juliano (setting standard curve by spectrophotometer and comparing the adsorption with the sample’s). Gelatinization temperature was estimated by the extent of alkali spreading and clearing of milled rice soaked in 1.7% KOH for 23 hours at room temperature. Organoleptic characteristics of cooked rice (iflavor, aroma) and apparent whiteness were judged by the taste panel using sensory evaluation method in triplicate. With respect to nutritional value, lysine amino acid was determined by using biological assay and applying Lactobacilllus delbrueckii while thiamine being measured through thiochrome fluorescence technique. The objective of this study was to examine the influence of solar drying process on the final quality of rice kernels and to compare the effects of this method with those in the traditional method of drying (natural sun drying). Results indicated that under the conditions prevailing in solar dryer, quality factors weren't affected except for whiteness of rice that too was better than that for sun dried samples. All other quality characteristics of the final product were acceptable in comparison with those in sun drying method.

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This paper presents mathematical models of thin layer forced convection solar drying of Cuminum cyminum using two drying methods (mixed and indirect) at different operating conditions. The average initial moisture content of the seeds for all tests was about 43% d.b. and the drying was performed continuously, in each test, for a uniform period of 90 minutes drying time in a solar cabinet dryer to obtain an average final moisture content of 8% d.b. Three airflow rates (0.084, 0.127 and 0.155 m3 s-1) were adopted and the experiments were run each sunny day from 11:30 to 13:00 with an average solar intensity of 750 W m-2 (±50 W m-2), ambient air temperature of 27°C (±1°C) and relative humidity of 30% (±1%). In order to find the most suitable form of thin layer solar drying model, eleven different mathematical models were selected using the experimental data to determine the pertinent coefficients for each model by applying the non-linear regression analysis technique. The goodness of fit was evaluated by calculating and comparing the statistical values of the coefficient of determination (R2), reduced chi-square (χ2) and root of mean square error (RMSE) for any model and for the two drying methods. The best results were found for the approximation of diffusion model with R2= 0.995, and RSME= 0.0199 in mixed mode type, and the Midilli model with R2= 0.994, and RSME= 0.0225 in indirect mode type thin layer solar drying.

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Outdoor experiments on a once-through single glazed solar air heater with perforated metal absorber plate were conducted to determine the practical effect of absorber plate porosity as well as suction air flow rate on the collector thermal efficiency and its total pressure drop. Three aluminum absorber plates were made perforated by drilling circular holes with different diameter/pitch ratios in square layout. A fan was employed at the top of the collector to suck ambient air from the bottom side through absorber plate perforations. The flow channel was designed such that uniform air flow over the entire absorber plate area could be achieved. Five levels of air mass flow rates (0.0065 to 0.0321 kg m-2 s-1) were adopted. Pressure drop across the apparatus was measured. The inlet air was preheated by short wavelength radiation absorbed by the cover as well as the long wavelength emission by the absorber prior to catching the heat from transpired absorber plate. A maximum thermal efficiency of 84% could be achieved for the most part of the porous absorber plate at the highest air mass flow rate. The collector with minimum porosity showed a maximum pressure drop. In some experiments, the glass cover was removed to determine the outdoor effect of glazing. Comparing the performance of the collector with and without glazing showed that the unglazed collector was about 25% less efficient than the glazed one at the same overall operating conditions. This reduction can be attributed to high top radiative and convective heat losses for the unglazed collector at the outdoor conditions. The pressure drop for the uncovered collector showed a lower magnitude in comparison to the covered one. The inlet air passes and heats up (21-59°C above the ambient) through the solar collector, therefore the fresh and clean hot air can be continuously supplied for many purposes such as solar drying system.

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The effect of apple and wheat fibers was studied on viability of Lactobacillus acidophilus in symbiotic yogurt and its physicochemical, sensory and rheological properties during 29 days storage at 5±1 ^ºC. The results of analysis showed that the number of Lactobacillus acidophilus in control and sample containing 0.5% fiber were reduced by 1 and 0.5 log cycle respectively and reached to 6 and 6.85 log cycle respectively at the end of storage period. But the sample containing 1% of fiber showed 0.25 log cycle increase in the number of Lactobacillus acidophilus at the same time and reached to 7.6 log cycle. This increase was higher in samples containing wheat fiber in comparison with those containing apple fiber (p<0.05). The samples containing fiber showed higher viscosity and lower syneresis in comparison with those not containing any fiber. The effect of wheat fiber on viscosity was higher than the effect of apple fiber (p<0.05). Increasing the amount of both fibers also caused samples to gain lower score for their color and taste. This decrease was obvious in samples containing apple fiber. Totally the samples containing 0.5% wheat fiber where known as best color and taste point of view between samples containing fiber. So it was concluded that using wheat fiber at the rate of 0.5% not only improved texture and chemical properties of yogurt but it could also provide the consumer satisfaction.  

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Gas chromatography (GC) and gas chromatography mass spectrometry (GC-MS) were employed to determine the chemical composition of essential oil obtained from dry fruits of Carum copticum. Thymol (36.7%), -terpinene (36.5%) and -cymene (21.1%) were found to be the major constituents of the oil. The anti-bacterial activities of the oil were mainly investigated against food poisoning bacteria (Salmonella thyphimorium, Pseudomonas aeruginosa, Entero-pathogenic Escherichia coli, and Staphylococcus aureus) by broth microdilution and agar diffusion methods. The oil exhibited significant anti-bacterial activities against all the examined bacteria. In conclusion, the results of this study showed that the oil of Ajowan is rich in monoterpenes and it may be used as a natural anti-bacterial agent in drug and food industries.

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Green fig, which is usually consumed as dry fruit, is one of the important non-oil export agricultural commodities of Iran. In this study, some important physical properties of green figs including geometric mean diamter, sphericity, porosity, particle and bulk density and pressure drop across a thin bed were measured at constant moisture content of 6% (dry basis). Air flow ranges used in this study were 0.4-1.0 m3 s-1 m-2 at three temperatures. The fig kernels were put together in thin layers in four different arrangements. The effect of filling methods and air flow rates on pressure drop were highly significant, while the air temperature did not show any appreciable effect on air flow resistance. Three applicable and most versatile models (Shedd, Hukill and Ives, and Ergun) were used to evaluate the pressure drop data. The Ergun model, with higher values of coefficient of determination (R2= 0.989) and lower value of root mean square error (RMSE= 21.84) and mean relative deviation modulus (P%= 6.69), was selected to be the best model for predicting pressure drop across green figs thin layer bed for the conditions studied.

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In this study the effect of grape fiber and chitosan on Lactobacillus Fermentum viability, physicochemical and sensorial properties in yoghurt containing kiwi was investigated during storage, using response surface methodology (RSM). Amounts of grape fiber, chitosan and storage time were in the range of 0-1.2 %, 0-1 % and 3-21 day, respectively. The results indicated that with increasing the amount of chitosan, Lactobacillus Fermentum viability decreased, but it was increased by increasing grape fiber during storage significantly (P<0.05). Moisture and syneresis of samples reduced significantly by increasing the amounts of chitosan and fiber (P<0.05). According to sensory evaluation, increasing the amounts of chitosan caused decrease in color scores. Flavor scores decreased as grape fiber increased significantly (P<0.05). In conclusion, using 0.9 % grape fiber, 0.1 % chitosan, and 12 day storage were found as optimum conditions for producing probiotic kiwi fruit yogurt.

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Drying characteristics of green pea (Pisum satium) with an initial moisture content of 76% (db) was studied in a fluidized bed dryer assisted by microwave heating. Four drying air temperatures (30, 40, 50 and 60ºC) and five microwave powers (180, 360, 540, 720 and 900W) were adopted. Several experiments were conducted to obtain data for sample moisture content versus drying time. The results showed that increasing the drying air temperature resulted in up to 5% decrease in drying time while in the microwave-assisted fluidized bed system, the drying time decreased dramatically up to 78.8%. As a result, addition of microwave energy to the fluidized bed drying is recommended to enhance the drying rate of green pea. Furthermore, in this study, the application of Artificial Neural Network (ANN) for predicting the drying time (output parameter) was investigated. Microwave power, drying air temperature, and green pea moisture content were considered as input parameters for the model. An ANN model with 50 neurons was selected for studying the influence of transfer functions and training algorithms. The results revealed that a network with the logsig (Log sigmoid) transfer function and trainrp (Resilient back propagation; Rprop) back propagation algorithm made the most accurate predictions for the green pea drying system. In order to test the ANN model, the root mean square error (RMSE), mean absolute error (MAE), and standard error (SE) were calculated and showed that the random errors were within and acceptable range of ±5% with a coefficient of determination (R2) of 98%.

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Goat's milk yogurt has a high nutritional value and digestibility and less allergenicity than cow's milk products. The problem with goat's milk yogurt is the specific taste that results from the high concentrations of volatile fatty acids that cause goat's taste and limit consumers acceptance of this product. In this research, the effects of adding 20% pineapple and peach nectar on physicochemical (dry matter, fat, protein, acidity, synersis, water holding capacity and viscosity) and sensory properties of goat's milk yogurt during 28 days of refrigerated storage were evaluated. The results showed that adding nectar significantly reduced the amount of dry matter (p <0.05). In nectar-containing samples, dry matter content had increasing trend during storage. Fat and protein levels were significantly lower than control samples (p <0.05). The pH of nectar containing yogurts during storage was significantly lower and its acidity was significantly higher than that of control yogurt (p <0.05). The trend of synersis changes in nectar-containing yogurt samples was rising in the first week and then decreased until the end of the storage period and the process of changes in water storage capacity was initially decreasing and then increasing. The viscosity increased during the first week and then decreased significantly until the end of the storage period (p <0.05). The viscosity of nectar-containing yogurt samples was significantly lower than that of control sample (p <0.05). Sensory evaluation results showed that the highest overall acceptance score was given to the sample containing pineapple nectar (4.66, 4.46) and the lowest overall acceptance score to the sample containing peach nectar (3.36, 3.33) due to its dark color and sour taste on the 1st and 14th days respectively . Based on the experiments, the use of pineapple nectar is a good method in order to cover goat taste in goat's milk yogurt with preserved its qualitative characteristics.

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Objective: Eukaryotic proteins generally have signal peptides which are not only crucial for their secretion efficiencies but are important for their expression levels. Coagulation factor IX (FIX) is a glycoprotein that plays a fundamental role in the blood coagulation pathway. Reduced levels or dysfunctional FIX are associated with hemophilia B. This study investigates the function of the human prothrombin signal peptide in an attempt to improve the human FIX (hFIX) secretion efficiency in a heterologous expression system. With this aim, we have used the SignalP and PrediSi programs for in silico evaluation of the signal peptide efficiency prior to conducting this experiment. Methods: We used molecular techniques to amplify and join the coding region of the human prothrombin signal peptide to the cDNA of mature hFIX. The chimeric fragment was examined for transient expression in a mammalian cell line (HEK293T) in comparison with the native hFIX, under a CMVp regulation. Using the neural network-based prediction programs, we evaluated the scores for cleavage position and secretion efficiency of the human prothrombin and hFIX signal peptides. The expression efficiencies of hFIX expressed by the recombinant cells were analyzed by RT-PCR and ELISA. Results: In silico analysis more efficiently predicted the human prothrombin signal peptide with a high score compared to the native hFIX signal peptide. This data was confirmed by the RT-PCR and ELISA results obtained from expression analyses at the RNA and protein levels, respectively. Conclusion: The present study showed that the signal peptide derived from the human prothrombin has the potential for efficient secretion of hFIX as evidenced by the results taken from a transient expression system. The results were consistent with in silico analysis. This replacement could be evaluated in a stable state condition.

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In this study, the effect of essential oils of dill in 4 levels of 0, 250, 500 and 750 µl/L in some physicochemical properties (moisture, acidity and pH), color index (a*, b* and L*), microbial (total count, Coliform, E Coli, mold and yeast) and sensory properties including color, flavor and texture of sun dried raisins during storage time was investigated. The results of statistical analysis of the data showed that during storage, the moisture and  indexes of b* (blue to yellow) and a* (green to red) and L* (brightness and darkness) of samples decreased significantly, but these properties with increasing amounts of essential oil of dill in the solution increased (p<0.01). Also during storage, with increasing the amount of dill essential oil, the acidity decreased and the pH increased (p<0.01). The results of microbial experiments showed that during storage, with increasing the amount of essential oil, the total count and coliforms decreased, which was significant in treatments containing 500 and 750 µl/L. The number of molds and yeasts also increased during the storage times and decreased with the amount of dill essential oil (p<0.05). According to the results of sensory evaluation, with increasing the amount of dill essential oil up 500 µl/L, the score of flavor and texture increased, but with further increase of the amount of essential oil caused decreased the flavor score compared to the control sample (P <0.05). Based on the results obtained of this study, the use of 500 µl/L of dill essential oil for storage of sun dried raisins, is recommended.