University of Tabriz
  • Tabriz, East Azerbayjan, Iran
Recent publications
Although rooster semen cryopreservation is an efficient procedure to spread qualified semen samples for reproductive goals, some post-thawed qualified semen samples resulted in poor fertility rate that could be related to epigenetic modifications during the cryopreservation process. This research was conducted to investigate the effect of reduced glutathione (GSH) in different cryopreservation extenders (Lake and Beltsville) on preservation of epigenetic modifications, fertility potential and other quality parameters of rooster sperm after thawing. Semen samples were collected and diluted in Lake and Beltsville extenders as follows: L-0: Lake without GSH, L-G: Lake with GSH, B-0: Beltsville without GSH, and B-G: Beltsville with GSH. After freeze-thawing process, sperm motility, membrane functionality, mitochondrial activity, acrosome integrity, viability, apoptosis status, lipid peroxidation, DNA fragmentation, ROS concentration, epigenetic modifications and fertility potential were evaluated. In results, the type of extender had no effect (P > 0.05) of post-thawed sperm quality. The treatments containing GSH presented higher (P ≤ 0.05) total motility, progressive motility, membrane functionality, mitochondrial activity, acrosome integrity, viability, DNA methylation, fertility as well as lower (P ≤ 0.05) lipid peroxidation, apoptosis, DNA fragmentation and ROS concentration than other treatments. Extender supplementation with GSH had no effect (P > 0.05) on histone methylation, histone acetylation and hatching rate. In conclusion, supplementation of rooster sperm cryopreservation extender with GSH could be an effective strategy to preserve post-thawed sperm DNA methylation, fertility and other quality parameters during reproductive programs.
A magnetic xanthan hydrogel/silk fibroin nanobiocomposite (XG hydrogel/SF/Fe3O4) was designed, fabricated, and characterized using analyzing methods such as FT-IR, EDX, FE-SEM, XRD, TGA, and VSM to evaluate the exact structure of product nanobiocomposite. The FE-SEM images reveal the presence of spherical shapes exhibiting a narrow size range and homogeneous distribution, measuring between 30 and 35 nm in diameter. The VSM analysis demonstrates the superparamagnetic properties of the XG hydrogel/SF/Fe3O4 nanobiocomposite, exhibiting a magnetic saturation of 54 emu/g at room temperature. The biological response of the nanobiocomposite scaffolds was assessed through cell viability and red blood cell hemolytic assays. MCF10A cells were exposed to a concentration of 1.75 mg/mL of the nanobiocomposite, and after 2 and 3 days, the cell viability was found to be 96.95 % and 97.02 %, respectively. The hemolytic effect was nearly 0 % even at higher concentrations (2 mg/mL). Furthermore, the magnetic nanobiocomposite showed excellent potential for hyperthermia applications, with a maximum specific absorption rate of 7 W/g for 1 mg/mL of the sample under a magnetic field in different frequencies (100, 200, 300, and 400 MHz) and 5 to 20 min time intervals.
This study addresses a topic neglected by the sport management literature: the impact of anticorruption effects of information and communication technology (ICT) in sport organizations on the role of organizational health mediation and organizational transparency. This study analyses this topic by presenting and testing a comprehensive theoretical model. This quantitative, descriptive survey uses structural equation modeling methodology. Data collection was carried out by employees ( N = 384) working at the Iranian Ministry of Sport and Youth. The results of the study were processed using LISREL 8.80 software in the model and hypothesis testing, and the study found support for the theoretical model. The results show that (a) ICT is an effective tool for reducing administrative corruption of officials, and (b) in terms of both organizational health (variance accounted for = 0.40) and organizational transparency (variance accounted for = 0.39), ICT has a mediating role in reducing administrative corruption in sport organizations. This study fills a gap in the literature by addressing both personal and managerial perspectives, thus allowing directors of sport organizations to consider ICT a useful and practical management tool for reducing corruption among officials in sport organizations, as an adjunct to traditional methods such as administrative reform and law enforcement.
In this study, we investigate the existence and uniqueness of a solution for a first-kind linear Volterra functional integral equation with proportional delay and weakly singular kernel, which has been stated as a research problem by H. Brunner (2017, pp. 99–100). We solve the problem numerically by the Tau-collocation method using Müntz-Jacobi polynomials along with the Gauss-Jacobi quadrature rule. Moreover, we prove a convergence theorem for the proposed method in L2\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\varvec{L}^{\varvec{2}}$$\end{document}-norm. We use several examples to corroborate the theoretical results and numerical efficiency of the method.
This study proposes a new design for a non‐isolated buck converter with continuous input current. As required, the integration of additional modules into the existing structure permits a significant decrease in the converter's gain to attain significantly lower values. In order to create the proposed converter, the input voltage connections to the Ćuk converter were changed. In this configuration, the operational state of the Ćuk converter has been changed from buck‐boost to step‐down by connecting the input power source's negative polarity to the inductor's terminal. In addition, the proposed converter benefits from a common ground between the input source and output port. Moreover, it can achieve a significant reduction in gain by increasing the number of series modules. Finally, the compact converter was smoothly incorporated onto a printed circuit board (PCB) and afterward validated by an output power of 80 watts.
Duckweed is a rapidly growing aquatic plant, which could be used in the diet of laying hens to enhance carbon capture and improve land use efficiency. Digestion may be improved by supplementation with exogenous enzymes. We replaced soyabean meal and wheat with duckweed in a 10‐week study with 432, 60‐week‐old Hy‐Line W‐36 layers, divided into six isocaloric and isonitrogenous dietary treatments, each with eight replicates. Two factors were investigated: first, duckweed substituted for wheat gluten meal and soyabean meal at 0, 7.5 and 15% of the diet, and second, with and without a multi‐enzyme supplement (500 mg/kg). Duckweed did not affect egg output or weight, but it improved yolk color ( P = 0.01) and reduced the liver enzymes aspartate aminotransferase ( P = 0.04) and alanine aminotransferase ( P = 0.02) in serum, suggesting hepatoprotective effects. Enzyme addition did not alter the effects of including duckweed in the diet, but it increased feed intake ( P = 0.03). It is concluded that, as well as offering the potential to increase land productivity, inclusion of duckweed in the diet of laying hens enhances egg yolk color and hepatoprotection, without detrimental effects on performance.
Magnetic bio-nanocomposite hydrogels are a promising platform for tissue engineering and drug delivery applications. This research presents the synthesis and characterization of novel magnetic bio-nanocomposite hydrogel beads based on magnetic hydroxyapatite nanoparticles and chitosan for potential pH-sensitive drug delivery. The successful synthesis was confirmed through various analysis methods. The prepared bio-nanocomposites hydrogel beads exhibited pH-sensitive swelling behavior. Furthermore, the bio-nanocomposites demonstrated a high loading capacity for doxorubicin (DOX) anticancer drug and a pH-sensitive drug release profile, with approximately 80% release rate at pH 5 and less than 10% release rate at pH 7.4. The Weibull kinetic model was the best-fitting function for DOX release from bio-nanocomposite hydrogels at pH 5. The cytotoxicity of DOX-loaded bio-nanocomposite hydrogels against HeLa cells was evaluated, which showed high cytotoxicity after incubation for 48 h at a concentration of 2.5 mg/mL. These findings suggest that the prepared magnetic bio-nanocomposite hydrogel beads have good potential for implantable pH-sensitive drug delivery in the treatment of cancerous tissue.
Epithelial–mesenchymal transition (EMT) is a cell remodeling process in which epithelial cells undergo a reversible phenotype switch via the loss of adhesion capacity and acquisition of mesenchymal characteristics. In other words, EMT activation can increase invasiveness and metastatic properties, and prevent the sensitivity of tumor cells to chemotherapeutics, as mesenchymal cells have a higher resistance to chemotherapy and immunotherapy. EMT is orchestrated by a complex and multifactorial network, often linked to episodic, transient, or partial events. A variety of factors have been implicated in EMT development. Based on this concept, multiple metabolic pathways and master transcription factors, such as Snail, Twist, and ZEB, can drive the EMT. Emerging evidence suggests that oxidative stress plays a significant role in EMT induction. One emerging theory is that reducing mitochondrial-derived reactive oxygen species production may contribute to EMT development. This review describes how metabolic pathways and transcription factors are linked to EMT induction and addresses the involvement of signaling pathways.
This paper proposes a switched Z‐source inverter with high voltage gain and low current stress on elements. Also, a new switching method corresponding to the proposed topology is introduced. This method is based on the usual Maximum Constant Boost (MCB) method. Hence, it has the advantages of the MCB method, such as low voltage stress on the inverter switches and high voltage gain. Also, eliminating part of the inverter's switching in this modulation method improves the inverter's efficiency. In addition to the Shoot‐Through (ST) duty cycle, another variable (N) affects the inverter's boost factor in this switching method. The proposed inverter's dynamic analysis shows that introducing N in the modulation method improved the dynamic characteristic of the inverter. Also, this variable as a control input can stabilize the dc side of the inverter in the closed‐loop control of the inverter. For the proposed topology, steady‐state analysis, dynamic analysis, elements design and efficiency calculation are performed. Also, the proposed topology is compared with the conventional topologies regarding boost factor, the number of elements, current stress on elements and efficiency to show its superiority. Finally, the experimental results are presented to verify theoretical discussions.
Considering the importance of reducing the use of chemical preservatives in food and the increasing attention of consumers to consume food products with minimal additives, the main goal of this research was to study the effect of use of chemical (calcium propionate) and biological ( Lactobacillus plantarum ) preservatives on increasing shelf life of yufka paste considering its physicochemical and microbial characteristics. For this purpose, three samples of yufka paste were prepared by adding concentrations of 10 ³ , 10 ⁵ , and 10 ⁷ cfu/mL of L. plantarum individually and three samples of paste were prepared by adding the same amount of bacteria in combination with 0.3% calcium propionate and these samples were compared with the control sample (without preservative) and the sample only containing 0.3% calcium propionate. The obtained results showed that different treatments and time had a significant effect on physicochemical properties including pH, moisture, and protein of yufka paste ( p < .05). The results of the survival of L. plantarum showed that with increasing time, the survival rate of bacteria increased ( p < .05). The pH of the samples showed that the L. plantarum has a significant effect on controlling the chemical quality of yufka during storage. The count of mold and yeast in the combined use of L. plantarum and 0.3% propionate was lower than the single use of propionate chemical preservative, which indicated the very good effect of the green preservative in controlling the moldy spoilage of yufka. Low concentrations of bacteria showed better antimold results than treatments containing bacteria and propionate in a combined form, propionate or control treatment.
Emotional artificial neural network (EANN) a new generation of artificial neural network linked to the wavelet-based data preprocessing method, was used in this study to predict air pollution in Tabriz city, Iran, from 2015 to 2019. For comparison purposes, the classic feedforward neural network (FFNN) model was applied. Daily meteorological data, as well as pollutants concentration data, were used to predict air pollution concentration in the future. The results showed the efficiency of the EANN model in comparison with classic FFNN in predicting air pollution for Tabriz city. Also, the wavelet EANN (WEANN) model outperformed the wavelet FFNN (WFFNN) and EANN models by up to 4 and 14%, respectively. This result denotes the importance of preprocessing method than applying more updated artificial intelligence methods. The superiority of the proposed WEANN approach is in better learning of extraordinary and extreme values in the validation phase, due to the improved ability of EANN via hormones in comparison with ANN.
In many practical applications such as motor drives, the inverter is required to produce a variable output voltage within a wide range (e.g., 0.1 to 1 pu). In such cases, when the inverter operates in low modulation index (low output voltage), the harmonic distortion of the output voltage increases due to considerable reduction in the magnitude of the fundamental component. Also, the ratio of the switching losses to the output power will be high in the low modulation index. In this paper, a simple solution is proposed to overcome the problems. The principle of the proposed solution is to adjust the DC‐link voltage so that the modulation index of the inverter remains within a specific high range. Different practical ways of obtaining controlled DC‐link voltage are presented. Also, for operation of the DC‐DC converter used for DC‐link voltage control, three strategies are proposed. The proposed solution is simple, and it is very effective and feasible to implement. To the best of the authors' knowledge, the idea has not been presented in this form previously. In order to verify the proposed solution, the simulation and experimental results are presented and discussed.
It has been documented that adequate maternal manganese (Mn) status is vital for performance and health of ewes and their newborn lambs. However, required level and form of dietary Mn in ruminants are not well defined. The current study was conducted to evaluate the effect of maternal organic Mn supplementation on performance, immunological status, blood biochemical and antioxidant status of Afshari ewes and their newborn lambs in transition period. For this purpose, various organic Mn concentrations were utilized as a supplementary ingredient in formulating the diets of ewes. The ewes were randomly allocated into three groups, fed with 0, and 80 mg/kg organic Mn supplemented diet. At the end of the experiment, the parameters including the performance of newborn lambs, as well as biochemical factors, immune status and antioxidant status in ewes and their newborn lambs were evaluated. The results showed a significant increase in the plasma concentrations of Mn, glucose, insulin, thyroid hormones (T 3 , T 4 ) and enzymatic antioxidants (SOD, GP X , CAT) in ewes and their newborn lambs that were treated with maternal organic Mn. Moreover, inorganic Mn treatments, the concentration of IgG in newborn lamb's plasma, and colostrum of ewes increased. According to this research, organic Mn acts as a valuable and safe supplementary material that could be exploited for enhancing health of ewes and their newborn lambs.
The importance of the parent vessel geometrical feature on the risk of cerebral aneurysm rupture is unavoidable. This study presents inclusive details on the hemodynamics of Internal carotid artery (ICA) aneurysms with different parent vessel mean diameters. Different aspects of blood hemodynamics are compared to find a reasonable connection between parent vessel mean diameter and significant hemodynamic factors of wall shear stress (WSS), oscillatory shear index (OSI), and pressure distribution. To access hemodynamic data, computational fluid dynamics is used to model the blood stream inside the cerebral aneurysms. A hemodynamic comparison of the selected cerebral aneurysm shows that the minimum WSS is reduced by about 71% as the parent vessel’s mean diameter is increased from 3.18 to 4.48 mm.
In this study, holocellulose was extracted from milled barley straw with different mesh sizes using Laccase enzyme. After extraction, a dual composite was made using montmorillonite clay to remove methylene blue dye from synthetic effluent. Results of different analysis methods including scanning electron microscope, Fourier transform infrared spectroscopy, and BET revealed that prepared nanocomposite presented desired specifications, and for smaller mesh sizes, derived holocellulose had higher quality due to high specific surface area. Response surface methodology was employed to reduce the number of experiments for methylene blue adsorption experiments and to achieve an empirical model for prediction of adsorption efficiency at different operating conditions. The effect of different factors including solution temperature, pH, initial dye concentration, and mesh size of milled barley straw on dye adsorption performance by prepared composite was examined. Maximum removal efficiency was obtained about 95% at temperature of 32 °C, pH of 8, initial dye concentration of 4 mg L ⁻¹ , and mesh size of 70. Also, isotherm studies were performed on experimental data using Langmuir, Freundlich, Temkin, and Dubinin–Radushkevich isotherm models and results revealed that the adsorption process follows Langmuir model with maximum predicted adsorption capacity of 159 mg g ⁻¹ , which implies monolayer adsorption. Moreover, thermodynamic study revealed that adsorption of methylene blue is endothermic and spontaneous while enthalpy and Gibbs free energy of adsorption are positive and negative, respectively. Finally, adsorption kinetic study determined that the pseudo-second-order kinetics model with correlation coefficient of about 1 best fitted the experimental results which is the characteristic of chemisorption process.
Recent advancements in nanostructured photodetectors have led to the development of a new metamaterial absorber design that enables control of light absorption and prevents the loss of photons. An optical simulation studied a broadband plasmonic metamaterial absorber using two-dimensional MXene (Ti 3 C 2 T x ) with arrays of tetragram shapes. By altering the angles of the edges of the tetragrams, the broadening of absorption can be tuned, resulting in high-efficiency absorption rates of over 90% for a broad range of wavelengths from 1200 nm to 2500 nm. Additionally, the coupling of PbS quantum dots to the colloidal plasmonic structure has been demonstrated, resulting in enhanced photon absorption capability of PbS QDs. This broadband PbS QD metamaterial absorber can be used as the channel in near-IR phototransistor devices. These findings contribute significantly to the field of photonics and have important implications for developing new and improved photodetectors.
In this study, the role of sac section area and parent vessel diameter on the hemodynamic feature of the blood flow in selected internal carotid artery (ICA) aneurysms is comprehensively investigated. The changes of wall shear stress, pressure, and oscillatory shear index (OSI) of blood stream on the vessel for various aneurysms with coiling treatment. To attain hemodynamic factors, computational technique is used for the modeling of non-Newtonian transient blood flow inside the three different ICA aneurysms. Three different saccular models with various Parent vessel mean Diameter is investigated in this study. The achieved outcomes show that increasing the diameter of the parent vessel directly decreases the OSI value on the sac surface. In addition, the mean wall shear stress decreases with the increase of the parent vessel diameter.
Identifying and extracting urban features such as buildings and producing accurate information about the location of features from remotely sensed images is important in updating maps, spatial databases, urban planning, and meeting the needs of urban services. Supervised methods of producing training data were widely applied in deriving accurate information from such images. However, those approaches require human intervention and are therefore time-consuming, and associated with classification accuracy limitations. This study presents a novel approach for extracting buildings from remotely sensed images by automating training data selection steps for supervised classification. To prepare training samples intelligently and automatically, a knowledge-based integration of radar and optical images was used. First, a general height constraint was applied to a digital surface model (DSM) obtained from radar images to divide the image pixels into two parts. Then, by applying a local height filter in each part, pixels representing buildings were extracted. Considering that the buildings are not the only features with significant heights, another constraint defined as coherence constraint was considered. Then, histogram of the optical image pixels corresponding to the filtered radar DSM pixels extracted from the previous steps was used to select sample training pixels. By considering pixels within the maximum range of the histogram, the final building samples for Support Vector Machine (SVM) classification were derived and applied for building extraction. The output showed that it sufficiently and reliably improved the existing supervised classification limitation to extract building. The performance of the proposed method was evaluated over different image datasets regardless of input image type and region. It achieved an overall average accuracy of 92% and a kappa coefficient of 0.83.
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5,394 members
Farzad Katiraee
  • Division of Mycology, Depatrment of Pathobiology
Mohammadreza Ghorani
  • Department of Pathobiology
Gholamreza Dehghan
  • Division of Biochemistry
Amir Karimi
  • Division of Physiology
29 Bahman Blvd., 5166616471, Tabriz, East Azerbayjan, Iran
Head of institution
Dr. Mir Reza Majidi