Forced vibration of a sandwich Timoshenko beam made of GPLRC and porous core

Mohammad Safari,Mehdi Mohammadimehr,Hossein Ashrafi 국제구조공학회 2023 Structural Engineering and Mechanics, An Int'l Jou Vol.88 No.1

In this study, forced vibration behavior of a piezo magneto electric sandwich Timoshenko beam is investigated. It is assumed a sandwich beam with porous core and graphene platelet reinforced composite (GPLRC) in facesheets subjected to magneto-electro-elastic and temperature-dependent material properties. The magneto electro platelets are under linear function along with the thickness that includes a cosine function and magnetic and electric constant potentials. The governing equations of motion are derived using modified strain gradient theory for microstructures. The effects of material length scale parameters, temperature change, different distributions of porous, various patterns of graphene platelets, and the core to face sheets thickness ratio on the natural frequency and excited frequency of a sandwich Timoshenko beam are scrutinized. Various size-dependent methods effects such as MSGT, MCST, and CT on the natural frequency is considered. Moreover, the final results affirm that the increase in porosity coefficient and volume fractions lead to an increase in the amount of natural frequency; while vice versa for the increment in the aspect ratio. From forced vibration analysis, it is understood that by increasing the values of volume fraction and the length thickness of GPL, the maximum deflection of a sandwich beam decreases. Also, it is concluded that increasing the temperature, the thickness of GPL, and the initial force leads to a decrease in the maximum deflection of GPL. It is also shown that resonance phenomenon occurs when the natural and excitation frequencies become equal to each other. Outcomes also reveal that the third natural frequency owns the minimum value of both deflection and frequency ratio and the first natural frequency has the maximum.

Use of Sourdough to Reduce Phytic Acid and Improve Zinc Bioavailability of a Traditional Flat Bread (Sangak) from Iran

Mohammad Ali Najafi,Karamatollah Rezaei,Mohammad Safari,Seyyed Hadi Razavi 한국식품과학회 2012 Food Science and Biotechnology Vol.21 No.1

In this study, effects of 8 different sourdough starters prepared with Saccharomyces cerevisiae, Lactobacillus plantarum, L. acidophilus, and Leuconostoc mesenteroides were investigated on the phytic acid level and mole ratio of phytic acid to zinc in a traditional Iranian bread (sangak). Different sourdough preparations were made and incubated at 30oC for 16 h and added to the dough at 10, 20, and 30% replacement levels. Use of sourdough resulted in a decrease in phytic acid level (also in a decrease in the phytic acid to zinc mole ratio) and corresponding increase in zinc bioavailability index when compared to the commercial sangak bread. The lowest phytic acid concentration and highest zinc bioavailability index were achieved when S. cerevisiae, L. plantarum, and Leu. mesenteroides were used at 30.0% dough replacement with sourdough. This study provides awareness about the negative impacts of higher phytic acid level in the breads,which is particularly the case for sangak bread, and also provides a solution for such issue.

Antiglycation and antioxidant activity of four Iranian medical plant extracts

Mohammad Reza Safari,Omid Azizi,Somayeh Sadat Heidary,Nejat Kheiripour,Alireza Pouyandeh Ravan 대한약침학회 2018 Journal of pharmacopuncture Vol.21 No.2

Objective: Diabetes mellitus (DM) is the most common metabolic disorder that defined by chronic hyperglycemia for the deficiency in insulin secretion or resistance. Hyperglycemia could induce non-enzymatic glycation of proteins. It has been suggested that some traditional plants can improve blood glucose and inhibit glycation process. This work evaluates and compares the anti-glycation activities of four Iranian plant extracts in vitro. Methods: The methanolic extract of “Fumaria officinalis, Stachys lavandulifolia, Salvia hydrangea and Rosa Damascene” was prepared in three different concentrations. Phenolic, flavonoids content and antioxidant activity were evaluated. The multistage glycation markers- fructosamines (early stage), protein carbonyls (intermediate stage) and β aggregation of albumin were investigated in the bovine serum albumin (BSA)/ glucose systemt. Results: All plants showed the high potency of scavenging free radicals and glycation inhibition in the following order: Fumaria officinalis> Rosa Damascene> Stachys lavandulifolia > Salvia hydrangea. There was a significant correlation between antioxidant and anti-glycation activity. Also, the antioxidant and anti-glycation capacity of extracts correlated with total phenolic and flavonoids content. Conclusion: Our findings demonstrated that the studied plants are good sources of anti-glycation and antioxidant compounds and, these properties can primarily attributable to phenolics, particularly flavonoids.

Free vibration of electro-magneto-thermo sandwich Timoshenko beam made of porous core and GPLRC

Safari, Mohammad,Mohammadimehr, Mehdi,Ashrafi, Hossein Techno-Press 2021 Advances in nano research Vol.10 No.2

In this article, free vibration behavior of electro-magneto-thermo sandwich Timoshenko beam made of porous core and Graphene Platelet Reinforced Composite (GPLRC) in a thermal environment is investigated. The governing equations of motion are derived by using the modified strain gradient theory for micro structures and Hamilton's principle. The magneto electro are under linear function along the thickness that contains magnetic and electric constant potentials and a cosine function. The effects of material length scale parameters, temperature change, various distributions of porous, different distributions of graphene platelets and thickness ratio on the natural frequency of Timoshenko beam are analyzed. The results show that an increase in aspect ratio, the temperature change, and the thickness of GPL leads to reduce the natural frequency; while vice versa for porous coefficient, volume fractions and length of GPL. Moreover, the effect of different size-dependent theories such as CT, MCST and MSGT on the natural frequency is investigated. It reveals that MSGT and CT have most and lowest values of natural frequency, respectively, because MSGT leads to increase the stiffness of micro Timoshenko sandwich beam by considering three material length scale parameters. It is seen that by increasing porosity coefficient, the natural frequency increases because both stiffness and mass matrices decreases, but the effect of reduction of mass matrix is more than stiffness matrix. Considering the piezo magneto-electric layers lead to enhance the stiffness of a micro beam, thus the natural frequency increases. It can be seen that with increasing of the value of WGPL, the stiffness of microbeam increases. As a result, the value of natural frequency enhances. It is shown that in hc/h = 0.7, the natural frequency for WGPL = 0.05 is 8% and 14% less than its for WGPL = 0.06 and WGPL = 0.07, respectively. The results show that with an increment in the length and width of GPLs, the natural frequency increases because the stiffness of micro structures enhances and vice versa for thickness of GPLs. It can be seen that the natural frequency for aGPL = 25 ㎛ and hc/h = 0.6 is 0.3% and 1% more than the one for aGPL = 5 ㎛ and aGPL = 1 ㎛, respectively.

Effects of Several Starter Cultures on the Anti-mold Activity and Sensory Attributes of a Traditional Flat Bread (Sangak) from Iran

Mohammad Ali Najafi,Karamatollah Rezaei,Mohammad Safari,Seyyed Hadi Razavi 한국식품과학회 2012 Food Science and Biotechnology Vol.21 No.1

Effects of 8 different sourdoughs and their replacement levels at 10, 20, and 30%(w/w) on the volume (of dough), crust hardness, organoleptic, and anti-mold properties of Iranian sangak bread were investigated. Saccharomyces cerevisiae, Lactobacillus plantarum,Lactobacillus acidophilus, and Leuconostoc mesenteroides were selected for the preparation of sourdough samples. The highest dough volume was achieved when sourdough (those having S. cerevisiae) was used at 30%. The highest taste scores were found with the bread sample using the above-mentioned starters at 30% sourdough replacement level. Considering the chewing, appearance, and overall quality of the new products, most of the samples maintained the favorite sensory aspects of sangak bread. Use of lactic acid bacteria and yeast strains as part of the sourdough formulation (followed by the use of sourdough in the dough formulation) resulted in improved crust properties and greater anti-mold activities.

Antiglycation and antioxidant activity of four Iranian medical plant extracts

Safari, Mohammad Reza,Azizi, Omid,Heidary, Somayeh Sadat,Kheiripour, Nejat,Ravan, Alireza Pouyandeh KOREAN PHARMACOPUNCTURE INSTITUTE 2018 Journal of pharmacopuncture Vol.21 No.2

Objective: Diabetes mellitus (DM) is the most common metabolic disorder that defined by chronic hyperglycemia for the deficiency in insulin secretion or resistance. Hyperglycemia could induce non-enzymatic glycation of proteins. It has been suggested that some traditional plants can improve blood glucose and inhibit glycation process. This work evaluates and compares the anti-glycation activities of four Iranian plant extracts in vitro. Methods: The methanolic extract of "Fumaria officinalis, Stachys lavandulifolia, Salvia hydrangea and Rosa Damascene" was prepared in three different concentrations. Phenolic, flavonoids content and antioxidant activity were evaluated. The multistage glycation markers- fructosamines (early stage), protein carbonyls (intermediate stage) and ${\beta}$ aggregation of albumin were investigated in the bovine serum albumin (BSA)/ glucose systemt. Results: All plants showed the high potency of scavenging free radicals and glycation inhibition in the following order: Fumaria officinalis> Rosa Damascene> Stachys lavandulifolia > Salvia hydrangea. There was a significant correlation between antioxidant and anti-glycation activity. Also, the antioxidant and anti-glycation capacity of extracts correlated with total phenolic and flavonoids content. Conclusion: Our findings demonstrated that the studied plants are good sources of anti-glycation and antioxidant compounds and, these properties can primarily attributable to phenolics, particularly flavonoids.

Live birth in a woman with recurrent implantation failure and adenomyosis following transfer of refrozen-warmed embryos

Safari, Somayyeh,Faramarzi, Azita,Agha-Rahimi, Azam,Khalili, Mohammad Ali The Korean Society for Reproductive Medicine 2016 Clinical and Experimental Reproductive Medicine Vol.43 No.3

The aim was to report a healthy live birth using re-vitrified-warmed cleavage-stage embryos derived from supernumerary warmed embryos after frozen embryo transfer (ET) in a patient with recurrent implantation failure (RIF). The case was a 39-year-old female with a history of polycystic ovarian syndrome and adenomyosis, along with RIF. After ovarian hyperstimulation, 33 cumulus-oocyte complexes were retrieved and fertilized with conventional in vitro fertilization and intracytoplasmic sperm injection. Because of the risk of ovarian hyperstimulation syndrome, 16 grade B and C embryos were vitrified. After 3 and 6 months, 3 and 4 B-C warmed embryos were transferred to the uterus, respectively. However, implantation did not take place. Ten months later, four embryos were warmed, two grade B 8-cell embryos were transferred, and two embryos were re-vitrified. One year later, the two re-vitrified cleavage-stage embryos were warmed, which resulted in a successful live birth. This finding showed that following first warming, it is feasible to refreeze supernumerary warmed embryos for subsequent ET in patients with a history of RIF.

Dendrosomal Curcumin Inhibits Metastatic Potential of Human SW480 Colon Cancer Cells through Down-regulation of Claudin1, Zeb1 and Hef1-1 Gene Expression

Esmatabadi, Mohammad Javad Dehghan,Farhangi, Baharak,Safari, Zahra,Kazerooni, Hanif,Shirzad, Hadi,Zolghadr, Fatemeh,Sadeghizadeh, Majid Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.6

Colon cancer is one of the leading causes of cancer-associated death worldwide. The prognosis for advanced colorectal cancers remains dismal, mainly due to the propensity for metastatic progression. Accordingly, there is a need for effective anti-metastasis therapeutic agents. Since a great body of research has indicated anticancer effects for curcumin, we investigated the effects of dendrosomal curcumin (DNC) on cellular migration and adhesion of human SW480 cells and possible molecular mechanisms involved. Different methods were applied in this study including MTT, Scratch and adhesion assays as well as real-time PCR and transwell chamber assays. Based on the results obtained, DNC inhibits metastasis by decreasing Hef 1, Zeb 1 and Claudin 1 mRNA levels and can reduce SW480 cell proliferation with $IC_{50}$values of 15.9, 11.6 and $7.64{\mu}M$ at 24, 48 and 72h post-treatment. Thus it might be considered as a safe formulation for therapeutic purpose in colorectal cancer cases.

Exploring the Potential of Explicit/Implicit Teaching through Plays for EFL Learners’ Pragmatic Development

S. Mohammad Baqerzadeh Hosseini,Mahmood Safari 아시아테플 2018 The Journal of Asia TEFL Vol.15 No.4

The present study investigated the possible contribution of plays as a medium of instruction for pragmatic development through explicit and implicit instruction. To this end, 80 English-major university students formed four intact experimental groups: two literary and two nonliterary groups. One of the literary groups (Implicit Play) received typographically enhanced plays containing the speech acts of apology, request, and refusal, and the other (Explicit Play) received the same plus metapragmatic instruction on the speech acts. The medium of instruction for the nonliterary groups were dialogs containing the given functions; they were also given either enhanced input (Implicit Dialog) or input plus metapragmatic information (Explicit Dialog). All the groups took a written discourse completion test (WDCT) and a multiple-choice discourse completion test (MDCT) before and after instruction. Analysis of the groups’ performance on the WDCT pretest and posttest did not show an advantage for the literary medium, that is, there was no significant difference between literary and nonliterary groups. It was rather the mode of instruction that mattered most; explicit groups outperformed their implicit counterparts. As for the groups’ performance on the MDCT pre and posttest, analyses revealed that the groups had improved, but there was no significant difference among the groups as a result of the four teaching conditions, suggesting that pragmatic instruction regardless of the medium and mode of teaching can improve learners’ knowledge of speech acts.

Eco-friendly High-Strength Refractory Concrete Containing Calcium Alumina Cement by Reusing Granite Waste as Aggregate

Kourosh Shirani,Mohammad Reisi,Mohammad Safari Savadkoohi 한국콘크리트학회 2022 International Journal of Concrete Structures and M Vol.16 No.1