Disturbance observer based anti-disturbance fault tolerant control for flexible satellites

Yadegari, Hamed,Khouane, Boulanouar,Yukai, Zhu,Chao, Han Techno-Press 2018 Advances in aircraft and spacecraft science Vol.5 No.4

In the field of aerospace engineering, accurate control of a spacecraft's orientation is often very important to mission success. Therefore, attitude control is a technically plentiful and extensively studied subject in controls literature during recent decades. This investigation of spacecraft attitude control is assumed to address two important aspects of the problem solutions. One sliding mode anti-disturbance control for utilization of faulty actuator components and another one disturbance observer based control to improve the pointing accuracy in the absence of anti-vibration equipment for the elastic appendages like a solar panel. Simultaneous occurrence of vibration due to flexible appendages and reaction degradation due to failure in attitude actuators complicates this case. The advantage of this method is acquisition proper control by the combination of disturbance observer and sliding mode compensation that form a fault tolerant control for the concerned satellite attitude control system. Furthermore, the proposed composite method indicates that occurrence the failure in actuators and even elastic solar panel vibration effect may be handled directly without reconfiguring the control components or providing piezoelectric devices. It's noteworthy, attitude quaternion and angular velocity commands are robustly tracked via controllers to become inclined to zero.

The effect of melatonin on prevention of bisphosphonate-related osteonecrosis of the jaw: an animal study in rats

Afshin Yadegari,Atousa Aminzadeh,Sam Seyyedkhamesi,Maedeh Aminian 대한구강악안면외과학회 2020 대한구강악안면외과학회지 Vol.46 No.4

Objectives: Melatonin induces human stem cells, converts pre-osteoblasts to mature osteoblasts, and reduces the duration of this transition. However, melatonin itself prevents activation of osteoclasts. Here, we evaluate the role of melatonin in prevention of bisphosphonate-related osteonecrosis of the jaw. Materials and Methods: In this experimental-interventional study, 30 rats were evaluated in 3 groups. The first and second groups received saline and zoledronic acid, respectively, for 4 weeks and the third group received 4 weeks of zoledronic acid and 3 weeks of melatonin simultaneously. Firstright-maxillary-molar extraction was performed for all animals, which were sacrificed after 4 weeks of recovery. The extraction sockets were examined histologically for the presence of osteonecrosis, number of osteoclasts and fibroblasts, severity of inflammation, and vascularization. Data were analyzed by chi-square, one-way ANOVA, Tukey, Kruskal-Wallis and Fisher’s exact statistical tests (α=0.05). Results: Osteonecrosis was observed in 20%, 90%, and 70% of the first, second and third groups, respectively (P=0.008). The lowest number of osteoclasts and fibroblasts was seen in the third group. Conclusion: Melatonin may effectively prevent some undesirable side effects of bisphosphonates. However, further studies are required to confirm the results of this study.

Female Gametophyte Development

Ramin Yadegari,Gary N. Drews 한국식물학회 2013 Journal of Plant Biology Vol.56 No.6

Great attention has been drawn toward researchon female gametophyte (FG) development, and many mutantshave been identified with abnormal formation. Althoughstudies are being conducted on the function and expressionof individual regulatory genes, only a few projects havefocused on gene regulatory networks. Here, we briefly reviewedthe molecular mechanisms and factors that affect FGdevelopment and discuss our ongoing investigations withgymnosperms. The progress that has already been reportedin this field serves as a strong foundation for future examinationsof those gene networks that control steps in plant reproduction.

Essential Oil Composition of Rosa damascena Mill. Produced With Different Storage Temperatures and Durations

Zeinolabedi Seify,Mehrab Yadegari,Abdollah Ghasemi Pirbalouti 한국원예학회 2018 원예과학기술지 Vol.36 No.4

The present study was conducted to investigate the effects of storage and temperature on the quality of Damask rose (Rosa damascena Mill.) flowers in southwestern Iran in 2016 and 2017. Flowers were harvested and distilled immediately or stored at 25°C, 4°C and -20°C for 6, 12, 24, 48 or 96 hours before distillation. Results obtained from GC/MS showed 39 essential oil components, most of which were beta citronellol, nonadecane, geraniol, trans geraniol, heneicosane, heptadecene and pentadecane. The highest (0.054% to 0.055%) and lowest (0.011% to 0.019%) levels of essential oil content were obtained at -20°C × 6 hours and 25°C × 96 hours post-harvesting, respectively. The highest percentage of beta citronellol (36.3 ± 1.2% to 35.1 ± 5.5%) was obtained at -20°C × 6 hours post-harvesting. Nonadecane levels increased with increasing storage time, particularly at -20°C × 96 hours post-harvesting (21.1 ± 0.08% to 16.2 ± 0.9%). Generally, the levels of most of the essential oil components decreased with increasing storage time, but this loss was avoided with freezing temperatures (-20°C).

Effect of Consumption of Whole-Wheat Breads on FBS, HbA1c, and Blood Lipids in Patients with Type 2 Diabetes

Javad Nazari,Nasrin Yadegari,Sousan Khodam,Amir Almasi-Hashian,Saeed Amini 한국식품영양과학회 2021 Preventive Nutrition and Food Science Vol.26 No.3

Whole-wheat can have positive effect on blood parameters, such as blood sugar and fat profiles, in patients with diabetic. The aim of this study was to assess the effect of whole-wheat breads on hemoglobin A1c (HbA1c) and blood lipids in patients with type 2 diabetes (T2D). The study population included men and women with T2D aged 30 years old and over in Arak, Iran. Using random sampling method, 60 patients with T2D were selected and randomly divided into control and intervention groups. After taking blood samples from the patients, the intervention group was administered 180 g of wholegrain wheat for 12 weeks. The participants were asked not to change their diets and amounts of physical activity during the study period. After 12 weeks, blood samples were taken and insulin resistance indexes, blood glucose levels, and lipid profiles were examined. The results indicated that consumption of whole-wheat bread for 12 weeks can significantly reduce body weight, and HbA1c, triglyceride, total cholesterol, and low density lipoprotein cholesterol (LDL-c) levels, and increase high density lipoprotein cholesterol (HDL-c) levels (P<0.05). However, in the control group, changes in body weight, body mass index, HbA1c, total cholesterol, HDL-c, and LDL-c levels did not significantly differ before and after the intervention period (P>0.05). As consumption of whole-wheat bread has positive effects on control of various physical and biochemical indictors in patients with diabetes, its consumption should be included in educational programs at health centers across the country.

Synthesis, characterization, electrochemical behavior, thermal study and antibacterial/antifungal properties of some new zinc(II) coordination compounds

Morteza Montazerozohori,Sahar Yadegari,Asghar Naghiha,Somayeh Veyseh 한국공업화학회 2014 Journal of Industrial and Engineering Chemistry Vol.20 No.1

A novel symmetrical Schiff base ligand was prepared by condensation reaction of 2,2-dimethyl-1.3-diaminopropane and (E)3-(2nitrophenyl)acrylaldehyde. The ligand and its Zn(II) coordinationcompounds were well characterized by the elemental analysis, FTIR, 1H, 13C NMR, UV–vis spectraand molar conductance. Thermal behaviors of all compounds were investigated from the roomtemperature to 600 ℃ with a heating rate of 10℃/min. Furthermore some decomposition thermo-kinetic parameters were evaluated by Coats–Redfern equation at each decomposition step. Electrochemical properties of ligand and its complexes were studied by cyclic voltammetry technique. Also antibacterial/antifungal activities of the ligand and its complexes were tested against three Gramnegativebacteria Escherichia coli (ATCC 25922), Salmonella spp. and Pseudomonas aeruginosa (ATCC 9027)and two Gram-positive bacteria Staphylococcus aureus (ATCC 6538) and Corynebacterium renale and alsothree fungi (Aspergillus niger, Penicillium chrysogenum and Candida albicans). The results exhibitedsuitable antibacterial/antifungal properties for ligand and Zn(II) complexes. The study has shown thatthe complexation of ligand to zinc center lead to enhancement of antibacterial/antifungal activity.

Gingival crevicular fluid levels of sclerostin in chronic periodontitis and healthy subjects

Esfahrood, Zeinab Rezaei,Yadegari, Zahra,Veysari, Setareh Kazemi,Kadkhodazadeh, Mahdi The Korean Association of Oral and Maxillofacial S 2018 대한구강악안면외과학회지 Vol.44 No.6

Objectives: Chronic periodontitis is a common inflammatory disease of the oral cavity that causes destruction of periodontal tissues and bone around the teeth. Sclerostin is a protein encoded by the SOST gene. In this study, gingival crevicular fluid (GCF) levels of sclerostin in patients with chronic periodontitis were compared with those of healthy subjects. Materials and Methods: In this case-control study, a total of 40 subjects were enrolled and divided into the healthy group (n=23) and chronic periodontitis group (n=17). GCF samples were collected, and the concentration of sclerostin was evaluated using enzyme-linked immunosorbent assay. Comparison of significance between groups was assessed using Mann-Whitney U test. Results: Sclerostin concentration was significantly higher in the chronic periodontitis group compared with the healthy group (P<0.005). Conclusion: Despite the limitations of this study, sclerostin can be a possible marker for assessment of periodontal health status.

Novel Method of ACO and Its Application to Rotor Position Estimation in a SRM under Normal and Faulty Conditions

Hossein Torkaman,Ebrahim Afjei,Hossein Babaee,Peyman Yadegari 전력전자학회 2011 JOURNAL OF POWER ELECTRONICS Vol.11 No.6

In this paper a novel method of the Ant Colony Optimization algorithm for rotor position estimation in Switched Reluctance Motors is presented. The data provided by the initial assumptions is one of the important aspects used to solve the problems relative to an Ant Colony algorithm. Considering the nature of a real ant colony, it was found that the ants have no primary data for deducing which is the shortest path in their initial iteration. They also do not have the ability to see the food sources at a distance. According to this point of view, a novel method is presented in which the rotor pole position relative to the corresponding stator pole in a switched reluctance motor is estimated with high accuracy using the active and inactive phase parameters. This new method gives acceptable results such as a desirable convergence together with an optimized and stable response. To the best knowledge of the authors, such an analysis has not been carried out previously.

Therapeutic effect of Ferula assa-foetida oleo-gum resin in rats with letrozole-induced polycystic ovary syndrome

Amir Shieh,Seyyed Majid Bagheri,Maryam Yadegari,Davoud Javidmehr,Zeinab Farhadi The Korean Society for Reproductive Medicine 2022 Clinical and Experimental Reproductive Medicine Vol.49 No.4

Objective: Asafoetida is a gum derived from Ferula assa-foetida, which is used in traditional Iranian medicine to treat some reproductive system disorders. The effects of asafoetida on ovarian tissue, expression of certain genes associated with polycystic ovary syndrome (PCOS), and levels of liver, kidney, and blood cell factors after treatment in a rat model were investigated. Methods: Thirty rats were divided into five groups: normal, polycystic, and treatment with three doses of asafoetida (12.5, 25, and 50 mg/kg for 3 weeks after PCOS induction). PCOS was induced by letrozole at a dose of 1 mg/kg administered orally for 3 weeks. Blood samples were taken, and the ovaries were removed and prepared for histomorphometric examination. Liver and kidney parameters were measured. The mRNA expression levels of luteinizing hormone receptor, CYP11A1, adenosine monophosphate-activated protein kinase, adiponectin, and adiponectin receptors 1 and 2 were also measured by real-time polymerase chain reaction. Results: The levels of liver, kidney, and blood parameters did not significantly differ between the treatment groups and the control group. At doses of 25 and 50 mg/kg, ovarian histopathology, especially the thicknesses of the theca and granulosa layers, was significantly improved relative to the PCOS group. The expression of target genes also improved in the 25 and 50 mg/kg treatment groups. Conclusion: Asafoetida can be used to treat PCOS as a complementary approach to conventional therapies. Asafoetida appears to act by regulating and activating metabolic and ovarian cycle enzymes.

Novel Method of ACO and Its Application to Rotor Position Estimation in a SRM under Normal and Faulty Conditions

Torkaman, Hossein,Afjei, Ebrahim,Babaee, Hossein,Yadegari, Peyman The Korean Institute of Power Electronics 2011 JOURNAL OF POWER ELECTRONICS Vol.11 No.6

In this paper a novel method of the Ant Colony Optimization algorithm for rotor position estimation in Switched Reluctance Motors is presented. The data provided by the initial assumptions is one of the important aspects used to solve the problems relative to an Ant Colony algorithm. Considering the nature of a real ant colony, it was found that the ants have no primary data for deducing which is the shortest path in their initial iteration. They also do not have the ability to see the food sources at a distance. According to this point of view, a novel method is presented in which the rotor pole position relative to the corresponding stator pole in a switched reluctance motor is estimated with high accuracy using the active and inactive phase parameters. This new method gives acceptable results such as a desirable convergence together with an optimized and stable response. To the best knowledge of the authors, such an analysis has not been carried out previously.