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Volume 21, Issue 1 (4-2018)
Abstract
Introduction: Cartilage is a tissue without vessel and lymph in body. If it has a massive defect, it cannot regenerate and reconstruct itself. In this society, cartilage diseases such as osteoarthritis and cartilage defects have increased. Its defects can disrupt the daily function of the patient and can be accompanied by pain due to bone wear. Common methods used to treat cartilage defects, which are considered invasive with low efficacy, include autologous chondrocytes, microfracture, bone marrow stimulation, and debridement. Current treatments are not definitive methods, which is why the use of stem cells and cartilage tissue engineering has been turned on. In the current review, the types of stem cells used in cartilage therapy and cartilage tissue engineering were investigated. Then, cellular signaling factors such as growth factors, mechanical and environmental factors were mentioned and referred to scaffolds based on the biomaterials used to engineer high-efficiency stem cells for the reconstruction of cartilage tissue. Therefore, the aim of this study was to review the use of stem cells in cartilage tissue regeneration and engineering.
Conclusion: The role of stem cells in regeneration of cartilage has been properly proven, but the mechanism and method of creating this regeneration has not yet been determined. Mesenchymal cells have the highest safety in cell therapy in cartilage, and these types of cells have the most clinical usage. In Iran, cell therapy is performed clinically for patients, but cartilage tissue engineering has not yet reached the clinical stage.
Volume 21, Issue 2 (7-2018)
Abstract
Aims: Growth factor (GFs) delivery with the certain concentration and release kinetic is one of the main challenges in tissue engineering. The aim of this study was the preparation and characterization of smart poly (N-isopropylacrylamide) nanoparticles containing vascular endothelial growth factor for induction of angiogenesis in human bone marrow-derived mesenchymal stem cells.
Materials and Methods: In this exprimental study, two different formulations of temperature-sensitive Poly (N-isopropylacrylamide) (PNIPAM) nanoparticles (NPs) were synthesized by free radical polymerization technique. Nanoprecipitation and diffusion methods were used to load the vascular endothelial growth factor (VEGF) in PNIPAM NPs. The effects of released VEGF on the differentiation of human bone marrow stem cells (hBMSCs) into endothelial cells in angiogenic, osteogenic, and 50% angiogenic-osteogenic culture medium were investigated, using flow cytometry and light microscope. Statistical analysis was performed, using the GraphPad Prism 6 software.
Findings: The nanoprecipitation process caused polymer degradation due to using the organic N, N-Dimethylacetamide solvent. The cumulative VEGF released after 72hours for 70%. A total of 10ng/ml VEGF released from PNIPAM nanoparticles, in 2D culture with cell density of 3×104 hBMSCs, after 7 days, leading to the endothelial differentiation, capillary-like tube formation, and expression of 20% vWF as angiogenic marker.
Conclusion: The PNIPAM NPs have the potential to load and release the angiogenic GFs for induction of angiogenesis in hBMSCs and in osteogenic medium.
Materials and Methods: In this exprimental study, two different formulations of temperature-sensitive Poly (N-isopropylacrylamide) (PNIPAM) nanoparticles (NPs) were synthesized by free radical polymerization technique. Nanoprecipitation and diffusion methods were used to load the vascular endothelial growth factor (VEGF) in PNIPAM NPs. The effects of released VEGF on the differentiation of human bone marrow stem cells (hBMSCs) into endothelial cells in angiogenic, osteogenic, and 50% angiogenic-osteogenic culture medium were investigated, using flow cytometry and light microscope. Statistical analysis was performed, using the GraphPad Prism 6 software.
Findings: The nanoprecipitation process caused polymer degradation due to using the organic N, N-Dimethylacetamide solvent. The cumulative VEGF released after 72hours for 70%. A total of 10ng/ml VEGF released from PNIPAM nanoparticles, in 2D culture with cell density of 3×104 hBMSCs, after 7 days, leading to the endothelial differentiation, capillary-like tube formation, and expression of 20% vWF as angiogenic marker.
Conclusion: The PNIPAM NPs have the potential to load and release the angiogenic GFs for induction of angiogenesis in hBMSCs and in osteogenic medium.
Volume 21, Issue 3 (5-2019)
Abstract
Onosma dichroantha Boiss. is a local medicinal herb in Iran, belonging to the Boraginaceae family that is used mainly for wound healing due to the presence of shikonin in its root cortex. Optimization of Onosma spp. in vitro cultures and shikonin production is encouraged as an alternative to harvesting the plant from its natural habitats. The present study evaluates the growth rate, several biochemical properties, and shikonin content of O. dichroantha plants treated with various concentrations of silicon (in the form of potassium silicate) in a hydroponic medium. Silicon application up to 0.5 mM increased the fresh mass, chlorophyll a/b, carotenoids, soluble proteins in shoots, and the lignin content in roots; however, phenolic compound contents were not significantly affected. In addition, silicon nutrition increased catalase and soluble ascorbate peroxidase activities, whereas polyphenol oxidase activity was not affected in roots and shoots. Interestingly, the shikonin content of O. dichroantha roots treated with increased concentrations of Si was 2-fold higher than that in the control plants, while the activity of phenylalanine ammonia lyase, a key enzyme in shikonin biosynthesis, was not affected. This suggests that the observed increase in shikonin in response to the silicon treatment could be due to increased stability or more accumulation sites of shikonin in roots. These data may be used for improvement of shikonin production in cell cultures of O. dichroantha under experimental or industrial conditions.
Volume 21, Issue 4 (7-2019)
Abstract
Trichoderma species are known as effective agents used for biological control of plant pathogenic fungi. The Trichoderma harzianum and its mutant isolates were cultured and their traits including, mycelial growth, antagonistic activity and extracellular proteins and enzymes production (Chitinase and Cellulase) were investigated to select the most effective mutant isolates against plant pathogenic fungus Rhizoctonia solani. Also, the purity and composition of enzyme-rich protein samples were evaluated under denaturing gel electrophoresis. This study clearly showed the possibility of improving mycelia growth rate (from 1.18 to 1.33 cm d-1), the antagonistic capability of Trichoderma (from 54.9% growth inhibition of R. solani to 66%), extracellular proteins and enzymes production for biological control of plant diseases through mutation with γ-radiation. Also, compared to wild type strain, protein production in the mutant isolates increased. Moreover, the highest specific chitinase enzyme activities were observed in mutant isolates T. h M8 (42.48 U mg-1) and T. h M15 (38.25 U mg-1). Trichoderma mutant of T. h M8 maintained higher mycelia growth rate and higher ability to inhibit growth of R. solani. The SDS-PAGE profiles had several enzyme protein bands such as CelloBioHydrolases (CBHs), EndoGlucanases (EGs), β-Glucosidases (BGLs), endochitinases, and β-(1, 4)-N-acetyl glucoaminidases. SDS-PAGE analysis indicated the presence of different protein bands in the range of 10.5 to 245 KDa. Interestingly, expression of chitinase in 95 percent of mutants was higher than wild type of T. harzianum. The results showed that gamma mutation could increase the efficiency and amount of enzymes in T. harzianum, while these enzymes are involved in antagonistic properties of T. harzianum.
Volume 21, Issue 6 (12-2021)
Abstract
There are many factors causing damages to a structure, including earthquakes, winds, environmental effects, etc. In order to repair a damaged structure, first its damage locations should be identified. Therefore, the damage identification of structures is considered as an important issue in civil engineering as well as mechanical engineering. Many methodologies have been devised for damage identification of structures, which are generally categorized to destructive and non-destructive cases. As a non-destructive damage identification approach, solving inverse problems for identifying the properties of a damaged structure is one of the popular methods which utilizes an optimization algorithm to minimize an error function in terms of measured strains or displacements. Since an iterative procedure with significant number of structural analyses should be carried out for the optimization process, an efficient numerical method should be employed to reduce the total computational cost. In this paper, the identification of hole in two-dimensional continuum structures is investigated with finite cell method and particle swarm optimization algorithm. The finite cell method is an efficient numerical method for solving the governing equations of continuum structures having geometrical complexity and/or discontinuities, which uses the concept of virtual domain method. The use of this concept makes the mesh generation easier such that the simple structured meshes can be utilized even for the curved boundaries of a structure, and hence mesh refinement is not necessary for the problems like damage detection. The finite cell method uses adaptive numerical integration for the cells including non-uniform material distribution. Accordingly, quadtree integration is utilized for the structural analysis using the finite cell method. Consequently, the computational time is significantly reduced. On the other hand, particle swarm optimization is a well-known meta-heuristic algorithm, and hence it does not require the gradient information of the problem. This population-based algorithm has been inspired by the social behaviour of animals such as fish schooling and birds flocking. The basis of this algorithm relies on the social influence and learning which enable individuals to preserve cognitive consistency. Thus, the exchange of ideas and interactions between individuals can lead them to solve optimization problems like damage detection. This study proposes the finite cell method and particle swarm optimization algorithm for damage detection of plate structures with single hole or multiple holes. As a non-gradient-based method, particle swarm optimization explores the search space to find the coordinates of the existing damage by minimizing an error function. This error function is evaluated by the strains or displacements calculated by the structural analysis utilizing the finite cell method. In order to evaluate the proposed methodology, numerical examples are provided to demonstrate the capability of finite cell method and particle swarm optimization algorithm in damage detection of two-dimensional structures. The first example considers the damage detection of a plate with a single hole, and it also considers the effects of mesh density. The second example employs a plate structure with three holes. The results demonstrate that the proposed methodology, with suitable computational efforts, can successfully be applied to damage detection of these structures.
Mohammad Mazidi Sharfabadi, Mohammad Iman Ghiasi, Ali Seraj,
Volume 21, Issue 11 (9-2021)
Volume 21, Issue 11 (9-2021)
Abstract
In this paper, the performance of a typical 190 W photovoltaic cell, located in Research Institute of Petroleum Industry, Tehran, Iran, has been studied and evaluated from the energy and exergy point of view. A computer code has been developed for modeling and determining the electrical characteristics of the system such as open circuit voltage, short circuit current, system resistances, maximum power point properties and characteristic curves. The operational and electrical parameters of the system and the environmental conditions such as solar radiation, wind speed and ambient temperature have been experimentally measured and logged on one typical day of May. For the validation of model, the results obtained from the model have been compared with the data reported by the manufacturer as well as the experimental data. The results show that the energy efficiency varies from 11.22 to 13.94 percent during the study period (7:30 AM to 5:30 PM) and its average is equal to 13.19 percent. The exergy efficiency also varies from 14.77 to 16.66 percent during the study period and its average is 15.62 percent.
Volume 21, Issue 147 (4-2024)
Abstract
In this study, the survival of Lactobacillus casei probiotic bacteria added to polylactic acid-nanocellulose nanocomposite film during 16 days of storage in the refrigerator was investigated. For this purpose, three edible films including polylactic acid, polylactic acid + nano cellulose, polylactic acid + nano cellulose+ Lactobacillus casei (9 log CFU/g) were prepared and the physical and mechanical characteristics of the films as well as the survival of Lactobacillus casei bacteria were investigated. The results of the mechanical test showed that the use of probiotic bacteria decreased the tensile strength and elongation at break of the polylactic acid-nanocellulose film (P < 0.05), but the addition of nanocellulose improved the mechanical properties of the polylactic acid film. The results of physical tests including humidity, solubility, water vapor permeability showed that the addition of probiotic bacteria and nanocellulose improved the physical properties of the film, but the opacity of the films increased (P<0.05). According to the results of the present study, with the increase in storage time, the survival of probiotic bacteria in the nanofilm decreased, and at the end of the storage period, its values were equal to 6.12 log CFU/g, but it was within the permissible range (6 log CFU/g).Therefore, the composition of Lactobacillus casei probiotic strain in the edible film can be its suitable carrier at refrigerator temperature
Volume 21, Issue 150 (6-2024)
Abstract
Kombucha is a functional drink which is obtained from the symbiotic culture of acetic acid bacteria and osmophilic yeasts in sweet tea and has a sour taste. During fermentation of this product, in addition to the many metabolites that are produced, a cellulose layer is formed by Acetobacter xyleneum in the fermented liquid. This drink has many benefits like probiotic and antioxidant properties, prevention and treatment of cancer and diabetes, increment the body’s metabolism, and etc. Also, the cellulose layer produced is used to remove metal contaminants from the effluent, treat wounds and burns, and as poultry dietary supplement. In this study, optimization of kombucha bacterial cellulose using sugarcane molasses as a source of carbon and energy, and in different environmental conditions (temperature (25, 27.5, 30 °C), incubation time (7, 11, 15 days), initial pH (5.5, 6, 6.5)) analyzed using central composite statistical plan. The results showed that concentration of sugarcane molasses, incubation time, and initial pH have significant effect on production of kombucha bacterial cellulose (p<0.05).
Volume 21, Issue 154 (12-2024)
Abstract
The crucial role of food in life has prompted a shift towards products that not only offer good quality and nutritional properties but also ensure the overall health of consumers. Probiotics, which are non-pathogenic microorganisms, can restore intestinal microbial balance when consumed in sufficient quantities. In this study, Limosilactobacillus fermentum ARD2 isolated from local yogurt was investigated for its probiotic properties. Various aspects of this strain were evaluated, including acid resistance (at pH levels of 2, 3 and 4), resistance to bile salts (at concentrations of 0.3, 0.5 and 0.7 %), antimicrobial activity using disk diffusion agar and well diffusion agar methods, resistance to common therapeutic antibiotics, evaluation of antioxidant activity, cell surface hydrophobicity, DNase enzyme activity, hemolytic activity, and biogenic amine and cholesterol absorption. The results of the acid resistance tests indicated that the viability of L. fermentum ARD2 increased as pH levels rose from 2 to 4, with a decrease observed over time at a constant pH over 3 hours. Growth was inhibited with increasing concentrations of bile salts. Antimicrobial testing revealed that the acidic and neutralized cell-free supernatant (aCFS and nCFS) had no significant antimicrobial effect on Escherichia coli, while nCFS showed no antimicrobial effect on Shigella dysenteriae. L. fermentum ARD2 exhibited resistance to Ciprofloxacin and was semi-sensitive to Penicillin and Nitrofurazone. The L. fermentum ARD2 showed considerable antioxidant activity, with DPPH and ABTS free radical inhibition rates of 41.40% and 43.60%, respectively. Additionally, it demonstrated the ability to reduce cholesterol absorption by 38.60%. The strain tested negative for DNase and hemolytic activities, and biogenic amine production was not observed. Based on these findings, L. fermentum ARD2 exhibits promising probiotic characteristics and could be utilized as a probiotic bacterium in food products.
Volume 21, Issue 155 (12-2024)
Abstract
Background and Aim: Breast cancer is a prevalent and heterogeneous disease affecting women worldwide. Probiotics, known as functional foods, have emerged as potential candidates in the fight against breast cancer, both in vivo and in vitro. Lactic Acid Bacteria (LAB), a group of probiotics, have been shown to have beneficial effects on host health and possess the potential to serve as adjuvant therapy for breast cancer prevention and treatment. This can be achieved through modulating immune responses and influencing the breast microbial community. This study aimed to screen and characterize probiotic Enterococci from Iranian traditional cheese and detect its cytotoxic effects on SK-BR-3 breast cancer cell line.
Materials and Methods: The LAB were isolated from two Iranian cheese samples after enrichment culture in MRS broth and then streak plate method on MRS agar. The LAB isolates were identified using macroscopic, microscopic, and molecular analyses. The cytotoxicity of LAB on SK-BR3 cancer cells was assessed using the MTT assay with bacterial concentrations of 100, 250, 500, and 1000 μg/ml.
Results: Molecular analysis revealed that the two isolates obtained in this study were closely related to Enterococcus species. They were designated as Enterococcus faecalis HBM-IAUF-3 and Enterococcus hirae HBM-IAUF-5, and their 16s-rDNA genome sequences were deposited in GenBank, NCBI under the accession numbers MG757697 and MG757702, respectively. Both Enterococcus faecalis HBM-IAUF-3 and Enterococcus hirae HBM-IAUF-5 exhibited the highest cytotoxicity against SK-BR3 cancer cells at a concentration of 1000 μl/ml after 72 hours.
Conclusion: This study reports the identification of novel Enterococcus strains from traditional Iranian dairy products that demonstrated cytotoxic effects on breast cancer SK-BR-3 cells. Encouraging the consumption of traditional organic dairy products and locally fermented foods may significantly reduce the risk of cancer.
Volume 21, Issue 156 (1-2025)
Abstract
Celiac disease is an autoimmune disorder which can cause serious damage to the mucous membrane of the small intestine due to the consumption of gluten, and as a result, there is a decrease in the absorption of nutrients, which can lead to weight loss, anemia and malnutrition. Removing gluten from the diet of the affected person is suggested as a solution to control and curb this abnormality. Therefore, the aim of this research is to investigate the possibility of producing cookies using rice flour, quinoa, carboxymethyl cellulose gum (1.5-3-5 percent) and gum extracted from the quince seed (1.5-3-5 percent) alone and evaluating its effect on the rheological characteristics of dough and textural properties of cookies. Based on the obtained results, it was determined that with the addition of gums, the viscosity increases compared to the control sample. Also by adding gums, Peak and Final viscosity increased and the setback viscosity decreased compared to the control sample. It was observed that the seed gum performed more effectively than showed carboxymethyl cellulose gum. So that the treatment with 5% quince gum has the highest viscosity among the samples. Furthermore the addition of both types of gum resulted in reduced hardness, increased springiness and improved sensory characteristics. Based on the overall evaluation of the results of the present study, sample number 7 containing 450 g rice flour, 50 g quinoa flour and 5% quince gum is recommended as the best treatment.
Volume 22, Issue 1 (10-2015)
Abstract
Imam Mohammed bin Idris al- Shafe‘i has had plenty of poetical talent and an extensive literal knowledge. It seems that his literal aspect has not taken into account much compared to other aspects of his personality. Whatever exists are testimony by some of the pioneers in the fields of knowledge and literature confirming his erudition in poetry and literature. After introducing the poetical and literary aspects of Shafe‘i’s personality, this article attempts to answer as: what are the subjects and the standards of Shafe‘i’s poem? After the research on his poetical works, the acquired results show that wisdom and value were two main subjects of Shafe‘i’s verses. Self-respect, modesty, contentment, generosity, virtue, good conduct, knowledge, excellence and affection for prophetic family, are the main terms in Shafe‘i’s poetical works.
Volume 22, Issue 1 (12-2018)
Abstract
Primordial germ cells (PGCs) are the specialized cells that are created from epiblast cells and after the migration differentiate into spermatogonial cells. Also, Spermatogonial cells differentiate into spermatids during the spermatogenesis process. Created disorders in each of these stages cause infertility, so the recognizing of the mechanism of these cells from the early stages of formation to the differentiation and investigating the effective factors in differentiation can be useful in the treatment of the infertile people. Today, the cultivation of spermatogonial cells and transplantation of these cells can be effective in the investigation of spermatogonial stem cell and the treatment of infertility. In this paper, the formation and migration of primordial germ cells, the spermatogenesis process and the effective factors in differentiation of spermatogonial stem cells are investigated.
Volume 22, Issue 1 (12-2018)
Abstract
Introduction: Due to increase of infertile couples, potential differentiation and proliferation of umbilical cord mesenchymal stem cells (MSCs) and bone marrow stem cells (BM-MSCs) was compared to find proper stem cells for differentiation into germ-like cells.
Materials & Methods: In this experimental study, isolated umbilical cord and bone marrow mesenchymal stem cells were treated by Retinoic acid (10-6M) and Sertoli cells condition medium. Viability percentage and the rate of proliferation (population doubling time) of cells was calculated in both groups. The number of colonies was evaluated in different days of culture, and finally the expression of and meiotic genes investigated by RT-PCR.
Findings: The viability percentage was higher in BM-MSCs group and the rate of proliferation of cells increased by elevating the passage number. The number of colonies in the bone marrow stem cells was significantly higher than that of the umbilical cord MSCs (p<0.05). In contrast, the expression of PLZF, OCT4 and SCP3 genes were detected in umbilical cord MSCs after 10 days of culture. However, in BM-MSC, the expression of PLZF and SCP3 genes was observed only after 15 days of culture.
Conclusion: It seems that the human umbilical MSCs higher differentiation potential for producing germ-like cells when compared to the Bone marrow stem cells. In contrast, the proliferation potential of BM-MSCs is greater than umbilical cord MSCs. This difference is probably due to secreted growth factors from these cells.
Materials & Methods: In this experimental study, isolated umbilical cord and bone marrow mesenchymal stem cells were treated by Retinoic acid (10-6M) and Sertoli cells condition medium. Viability percentage and the rate of proliferation (population doubling time) of cells was calculated in both groups. The number of colonies was evaluated in different days of culture, and finally the expression of and meiotic genes investigated by RT-PCR.
Findings: The viability percentage was higher in BM-MSCs group and the rate of proliferation of cells increased by elevating the passage number. The number of colonies in the bone marrow stem cells was significantly higher than that of the umbilical cord MSCs (p<0.05). In contrast, the expression of PLZF, OCT4 and SCP3 genes were detected in umbilical cord MSCs after 10 days of culture. However, in BM-MSC, the expression of PLZF and SCP3 genes was observed only after 15 days of culture.
Conclusion: It seems that the human umbilical MSCs higher differentiation potential for producing germ-like cells when compared to the Bone marrow stem cells. In contrast, the proliferation potential of BM-MSCs is greater than umbilical cord MSCs. This difference is probably due to secreted growth factors from these cells.
Moein Taheri, Mahdi Mirzaluo,
Volume 22, Issue 1 (12-2021)
Volume 22, Issue 1 (12-2021)
Abstract
Mutations in DNA and the development of mutated genes that are inherited or acquired during a personchr('39')s lifetime can cause cancer. This type of disease causes the loss of normal control of cell growth and proliferation. Breast cancer, with its prevalence in both men and women and the higher incidence of women in the female population, is one of the most important cancers in the medical community. Appearance changes in the breast, the presence of a lump, and discharge and bleeding from the nipple are signs of breast cancer. Targeted treatment of this disease reduces the complications of treatment methods. Also, recognizing the mechanical properties of the cell, such as the Youngchr('39')s modulus, and examining the changes caused by cancer in these properties will make treatment more efficient and help the pharmaceutical sciences. For this purpose, in this paper, the MCF-10 breast cell has been studied using atomic force microscopy and nanomanipulation method. Atomic force microscope is one of the efficient tools in the structural studies of biological particles with the possibility of producing images of soft tissues under different environmental conditions and in a non-destructive manner. Chung, chen and brake contact are the models used in the simulation. Finally, with the simulations performed, the Young modulus of 1200 Pa is considered for this cell. Also, considering the comparisons made with experimental work, the chen contact model has been introduced as the optimal model for extracting cellular properties.
Volume 22, Issue 2 (6-2022)
Abstract
Abstract
Surface fault rupture is very dangerous for critical buildings and infrastructures located in or near active faults and can cause irreparable damages. These structures must be designed by considering the undesirable effects of surface faulting. In this case, geotechnical measures, especially the construction of reinforced earth foundations are very effective in reducing the adverse effects of surface faults. The ASTM designation primarily recommends avoiding constructions to the adjacent of active faults probable of causing rupture at ground surface during an earthquake, although it is hard to determine the exact location of surface faulting. The increasing growth of population and the need to develop cities, particularly in metropolitan areas with economic limitations or land restrictions, have attracted the attention of the engineering community more than before to carry out feasibility studies on the construction of buildings in active fault zones. Such a consideration does not negate that the primary recommendation to avoid construction of buildings over active fault zones is the most convenient solution; it rather aims at examining and making engineering arrangements for the construction of buildings in zones with surface faulting potential governable by engineering methods. In addition to buildings, linear projects such as roads, highways, and tunnels must cross regions probable of surface faulting. Therefore, geotechnical measures, particularly designing reinforced soil foundations, contribute significantly to the reduction of undesirable effects of surface faulting. This research is conducted based on a series of tests on foundations reinforced with geogrid, geocell, and a combination of both, subject to normal faulting, to reduce surface faulting ruptures. The tests simulate the behavior of a 1.5 m wide strip foundation, placed over 6 m thick alluvium, subjected to a displacement of 60 cm. Seven tests were performed by different types and numbers of reinforcement, which were scaled to 10. The image analysis was carried out to examine the ground settlement profile, angular distortion, and fault propagation path. The results showed that the geotextiles used in the reinforced soil foundation could effectively reduce the angular distortion, cause uniform settlement, and divert fault propagation path, all protecting the structure against faulting. In a foundation reinforced with one layer of geogrid, a uniform settlement occurred at fault-induced displacement. In particular, the geogrid largely affected fault distribution, angular distortion reduction, and uniform ground settlement. Also, the settlement occurred at a wider zone and reduced the angular distortion by 60%. It means that the geocell affected the reduction of angular distortion and creation of uniform settlement by about 30%; however, it did not affect faulting diversion. The results indicate that the foundation reinforced with a combination of geocell and geogrid reduces angular distortion by 70% acted almost the same as the foundation reinforced with one layer of geogrid. Due to the increased stiffness and compressive strength of geocell, the shear band was more diverted toward the left side, compared to the foundation reinforced with one layer of geogrid. The right boundary of the shear band was also moved to the left corner of the structure. Likewise, the foundation reinforced with a combination of two layers of geogrid and three layers of geogrid reduces angular distortion by 80%. The results also reveal that adding more than two layers of geogrid had no effect on angular distortion reduction and the fault propagation path was more diverted as the number of geogrid layers increased.
Surface fault rupture is very dangerous for critical buildings and infrastructures located in or near active faults and can cause irreparable damages. These structures must be designed by considering the undesirable effects of surface faulting. In this case, geotechnical measures, especially the construction of reinforced earth foundations are very effective in reducing the adverse effects of surface faults. The ASTM designation primarily recommends avoiding constructions to the adjacent of active faults probable of causing rupture at ground surface during an earthquake, although it is hard to determine the exact location of surface faulting. The increasing growth of population and the need to develop cities, particularly in metropolitan areas with economic limitations or land restrictions, have attracted the attention of the engineering community more than before to carry out feasibility studies on the construction of buildings in active fault zones. Such a consideration does not negate that the primary recommendation to avoid construction of buildings over active fault zones is the most convenient solution; it rather aims at examining and making engineering arrangements for the construction of buildings in zones with surface faulting potential governable by engineering methods. In addition to buildings, linear projects such as roads, highways, and tunnels must cross regions probable of surface faulting. Therefore, geotechnical measures, particularly designing reinforced soil foundations, contribute significantly to the reduction of undesirable effects of surface faulting. This research is conducted based on a series of tests on foundations reinforced with geogrid, geocell, and a combination of both, subject to normal faulting, to reduce surface faulting ruptures. The tests simulate the behavior of a 1.5 m wide strip foundation, placed over 6 m thick alluvium, subjected to a displacement of 60 cm. Seven tests were performed by different types and numbers of reinforcement, which were scaled to 10. The image analysis was carried out to examine the ground settlement profile, angular distortion, and fault propagation path. The results showed that the geotextiles used in the reinforced soil foundation could effectively reduce the angular distortion, cause uniform settlement, and divert fault propagation path, all protecting the structure against faulting. In a foundation reinforced with one layer of geogrid, a uniform settlement occurred at fault-induced displacement. In particular, the geogrid largely affected fault distribution, angular distortion reduction, and uniform ground settlement. Also, the settlement occurred at a wider zone and reduced the angular distortion by 60%. It means that the geocell affected the reduction of angular distortion and creation of uniform settlement by about 30%; however, it did not affect faulting diversion. The results indicate that the foundation reinforced with a combination of geocell and geogrid reduces angular distortion by 70% acted almost the same as the foundation reinforced with one layer of geogrid. Due to the increased stiffness and compressive strength of geocell, the shear band was more diverted toward the left side, compared to the foundation reinforced with one layer of geogrid. The right boundary of the shear band was also moved to the left corner of the structure. Likewise, the foundation reinforced with a combination of two layers of geogrid and three layers of geogrid reduces angular distortion by 80%. The results also reveal that adding more than two layers of geogrid had no effect on angular distortion reduction and the fault propagation path was more diverted as the number of geogrid layers increased.
Volume 22, Issue 3 (7-2019)
Abstract
Aims: The present study aimed to evaluate the developmental rate of ovarian follicles and the incidence of cell death in grafted immature mouse ovarian tissue encapsulated and non-capsulated in sodium alginate.
Materials and Methods: Female (NMRI) mice (n=50) were divided into 3 groups as follows: Group A; the right ovary was removed and encapsulated in sodium alginate then transplanted under kidney capsule, Group B; the right ovary was removed and without encapsulation transplanted under kidney capsule, in both transplanted groups the left ovary was intact. Group C; control group, both ovaries were intact. After transplantation, in the first and fourth estrous cycles at proestrus phase. The morphology of the grafted ovaries, and the percentage of normal follicles were evaluated using hematoxylin and eosin staining. The incidence of apoptosis cell death was evaluated by anti-BAX immunohistochemical staining.
Findings: At first and fourth estrous cycle, almost 99.5% of follicles had normal morphology and no significant difference was observed between the groups. The follicular development and growth rate in the two grafted groups, was significantly higher than the control group, moreover, these rates were higher in the capsulated group than non-capsulated once (p<0.05). In spite of the presence of some BAX positive cells in the preantral and antral follicles, there was no remarkable reaction for BAX antibody in the primordial and primary follicles in studied groups.
Conclusion: Despite the high developmental rat and premature ovarian reserve depletion in grafted groups that can affect the longevity of transplanted tissue, while sodium alginate has a positive effect on the follicular development in grafted tissue.
Farnoud Norouzi Niyaee, Kamran Taheri Sartang, Mohammad Mahan Taheri Sartangtaghavi Farahi, Rasoul Taheri Sartangtaghavi Farahifesharakifard, ,
Volume 22, Issue 10 (10-2022)
Volume 22, Issue 10 (10-2022)
Abstract
Choosing the right equipment in terms of price, performance and reliability, is one of the main challenges in the automation industry. Among these equipments, electric motors are the most important elements which are widely used in the industries. Electro motors selection is made according to certain rules and principles, and it is very important to know the governing conditions. Using amotor with less power than required will lead to system failure and a motor with much more power will result in extra costs. In this article, scientific selection of an electric motor for the bending process in an automation system has been discussed. Using real conditions of a manufacturer and available data in articles and books, the necessary relationships were extracted. 28 number of motors (among the available ones) were nominated in the first stage of preliminary monitoring. Then, by applying other prevailing conditions and characteristics, 3 motors with different powers selected for final investigations. Eventually, after using Simscape simulations & exerting less energy consumption criteria, the 5RK90GE-CW2ML2 motor (manufactured by Oriental Motor Company) was selected and was approved after satisfying the power, quality and safety conditions.
Volume 22, Issue 158 (3-2025)
Abstract
Paenibacillus polymyxa is one of the microorganisms that has the ability to produce extracellular exopolysaccharides and antibiotics. Several factors, including culture medium content, carbon and nitrogen sources, pH, temperature, air velocity, and culture conditions, have an effect on the growth and production of higher cell mass, as well as the production of microbial metabolites. The purpose of this study was to investigate the growth rate of P. polymyxa in a culture medium containing molasses and to screen five components of the culture medium along with four factors of the fermentation conditions using the Plackett -Burman method to maximize cell mass production. The results showed that among the investigated variables, molasses brix, time, percentage of inoculation, amount of ammonium sulfate, stirring speed, and the amount of glucose and urea, as a first-order equatino, had a significant positive effect on bacterial growth and biomass production. Molasses brix medium was found to be more effective than other variables; however, pH and the amount of low-use elements had a negative effect on cell growth. The findings of this study indicated that molasses-based culture medium can be used as a cost-effective and suitable option for the growth of P. polymyxa.
Volume 22, Issue 159 (4-2025)
Abstract
The purpose of this study is to investigate the ability of smart scaffolds of Kappa-carrageenan (Carr) and the combination of Kappa-carrageenan and quince seed mucilage (Carr:Quc) to support C2C12 viability and growth for cultured meat production. Carr and Carr:Quc with a final concentration of 1.5% (v/w) were developed using a 5% potassium chloride solution. The capability of the scaffolds to respond to the pH change of the environment was evaluated, and the viability of C2C12 at normal pH (7.4) and varying pH levels (7.4-5.5) was assessed. The evaluation of swelling changes with varying pH (pH 1-7) showed that for the Carr scaffold, the highest swelling was observed at pH 5, reaching 145%, which showed a significant difference compared to swelling at other pH levels (p < 0.05). The highest swelling for the Carr:Quc scaffold was also observed at pH 5, reaching 428%, with a significant difference compared to swelling at other pH levels (p < 0.05). Moreover, the change in the swelling behavior of the scaffolds was evaluated by changing the pH from 7.4 to 5.5. Carr did not show any swelling change, while Carr:Quc demonstrated a significant change in swelling after exposure to pH 5.5 for 30, 45, 60, 180, and 360 min. On Carr:Quc, C2C12 showed higher viability in normal conditions compared to varying pH levels from 7.4 to 5.5. Furthermore, after culturing on Carr:Quc, C2C12 maintained their viability throughout the culture period for 15 days at pH 7.4 and showed the potential for spheroid formation. The findings of this study could pave the way for the design of scaffolds made of edible biopolymers to facilitate tissue engineering of cultured meat