Stability analyses of articulated rigid pipes conveying fluid with harmonic velocity using the method of multiple time scales

Javad Mohammadi,Mansour Nikkhah Bahrami 대한기계학회 2020 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.34 No.3

The stability of two rigid articulated pipes conveying fluid is considered. The velocity of fluid motion is harmonic. Parametric resonance for the second mode and 3:1 internal resonance in the presence of self-excited are considered. The method of multiple time scales has been applied for analysis. The effects of initial velocity 0 u , ratio fluid mass per total fluid mass and pipes mass g and flow frequency b on the frequency response for steady state and stability analyses are studied. Some comparative studies on the stability region of system are conducted with the results available in the open literature.

Effect of Transcutaneous Electrical Nerve Stimulation on the Pain Intensity During Insertion of Needle in Patients Undergoing Spinal Anesthesia: A Randomized Controlled Study

Javad AminiSaman,Hasan A. Karimpour,Behzad Hemmatpour,Saeed Mohammadi,Saeed Darvishi,Rasool Kawyannejad 사단법인약침학회 2020 Journal of Acupuncture & Meridian Studies Vol.13 No.3

Background and objectives: Needle insertion pain during spinal anesthesia is an unpleasant experience for patients. This study aimed to investigate the effects of Transcutaneous Electrical Nerve Stimulation (TENS) on the pain intensity during the insertion of spinal needles in patients undergoing spinal anesthesia. Materials and methods: In a double-blind clinical trial, 60 candidates for elective Trans Ureteral Lithotripsy surgery under spinal anesthesia were randomly divided into intervention and control groups. The electrodes of the TENS device were placed in the space between L3-L4 and L5-S1 vertebrae. The intensity of pain during insertion of the spinal needle by Visual Analog Scale and the frequency of attempts were recorded. Results: The mean age of the study samples was 34.26 ± 5.07 and 32.8 ± 5.28 in the control and intervention group, respectively. The pain intensity during insertion of spinal needles was less significant in the intervention group compared to the control group (p = 0.001). The number of attempts to the spinal needle between the two groups was not statistically significant (p = 0.51). The duration of spinal anesthesia implementation procedure by physician in the intervention group was significantly shorter than that of the control group (p = 0.001). Conclusion: The use of TENS effectively reduced the pain of spinal needle insertion. Considering these beneficial effects, it is suggested that this procedure be used to relive pain in patients with spinal anesthesia.

Transcutaneous Electrical Nerve Stimulation at the Acupuncture Points to Relieve Pain of Patients Under Mechanical Ventilation: A Randomized Controlled Study

Javad AminiSaman,Saeed Mohammadi,HasanAli Karimpour,Behzad Hemmatpour,Hengameh Sharifi,Rasool Kawyannejad 사단법인약침학회 2018 Journal of Acupuncture & Meridian Studies Vol.11 No.5

Background and objectiveElectrical stimulation and acupuncture points as nonpharmacological methods have been the focus of pain reduction in different patients. This study is aimed at determining the effects of transcutaneous electrical nerve stimulation (TENS) on the acupuncture points of pain in patients under mechanical ventilators. Materials and methodsThis randomized double-blind clinical trial study was conducted on 50 patients undergoing mechanical ventilation in intensive care units of Imam Reza hospital in Kermanshah, Iran, in 2017. The patients were randomly allocated into intervention and placebo groups. In the intervention group, TENS electrodes were placed on points Hegu and Zusanli. Pain severity was measured using the Care Pain Observation Tool scale, and the dosages of narcotics and sedation intake were recorded. Data were analyzed using the Statistical Package for the Social Sciences (SPSS) software, version 19. ResultsThe level of pain in patients decreased in the intervention group in comparison with the sham group, and this decline was significant during certain hours (p < 0.05). The amount of analgesic and sedation drugs used was less significant in the intervention group than in the sham group (p = 0.01; p = 0.04). ConclusionThe results showed that the use of TENS on acupuncture points can decrease the level of pain and opioid consumption in intubated patients under a mechanical ventilator.

Assessment of pH Responsive Delivery of Methotrexate Based on PHEMA-st-PEG-DA Nanohydrogels

Javad Farzanfar,Fatemeh Farjadian,Amir Roointan,Soliman Mohammadi-Samani,Lobat Tayebi 한국고분자학회 2021 Macromolecular Research Vol.29 No.1

Nanohydrogels (NHs) are novel and attractive carriers for various anticancer factors delivery. The objective of present study is development of a safe NH for pH responsive delivery of methotrexate (MTX). Herein, poly (hydroxyethyl methacrylate) is utilized as the main structure, which is cross-linked with poly(ethyleneglycol) diacrylate (PEG-DA) through reversible addition fragmentation chain transfer polymerization technique. After synthesis, the developed structure is characterized using different methods, including 1H NMR, FT-IR, size exclusion chromatography, transmission electron microscopy and dynamic light scattering. The results confirm successful synthesis of the NH with acceptable yield and nano scale mean size of 194 nm. Methotrexate is conjugated with the aforementioned structure through pH responsive esteric bond. The efficiency of the prepared NH in loading and release of the anticancer drug, methotrexate, is tested. The developed NH shows great potential in methotrexate loading, as well as a faster release rate of methotrexate in acidic pH. The results of in vitro toxicity assessment on MCF-7 as a breast cancer cell line reveal an improved cytotoxicity induction by the methotrexate loaded particles when compared with the free MTX molecules. The suitable size (<200 nm), great potential in loading and release of the methotrexate and cytotoxicity induction in cancer cells are the reliable features of NH as an ideal anti-cancer vehicle.

Time delay study for semi-active control of coupled adjacent structures using MR damper

Javad Katebi,Samira Mohammady Zadeh 국제구조공학회 2016 Structural Engineering and Mechanics, An Int'l Jou Vol.58 No.6

The pounding phenomenon in adjacent structures happens in severing earthquakes that can cause great damages. Connecting neighboring structures with active and semi-active control devices is an effective method to avoid mutual colliding between neighboring buildings. One of the most important issues in control systems is applying online control force. There will be a time delay if the prose of producing control force does not perform on time. This paper proposed a time-delay compensation method in coupled structures control, with semi-active Magnetorheological (MR) damper. This method based on Newmark’s integration is adopted to mitigate the time-delay effect. In this study, Lyapunov's direct approach is employed to compute demanded voltage for MR dampers. Using Lyapunov's direct algorithm guarantees the system stability to design a controller based on feedback. Because of the strong nonlinearity of MR dampers, the equation of motion of coupled structures becomes an involved equation, and it is impossible to solve it with the common time step methods. In present paper modified Newmark-Beta integration based on the instantaneous optimal control algorithm, used to solve the involved equation. In this method, the response of a coupled system estimated base on optimal control force. Two MDOF structures with different degrees of freedom are finally considered as a numeric example. The numerical results show, the Newmark compensation is an efficient method to decrease the negative effect of time delay in coupled systems; furthermore, instantaneous optimal control algorithm can estimate the response of structures suitable.

Comparative Evaluation of Antioxidant and Anti Food-borne Bacterial Activities of Essential Oils from Some Spices Commonly Consumed in Iran

Javad Aliakbarlu,Surur Khalili Sadaghiani,Shadieh Mohammadi 한국식품과학회 2013 Food Science and Biotechnology Vol.22 No.6

The antioxidant potency, anti food bornebacterial activity, and total phenolic contents of essentialoils (EOs) from avishane shirazi (Zataria multiflora), clove(Syzgium aromaticum), cinnamon (Cinnamomum zeylanicum),cumin (Cuminum cyminum), black cumin (Buniumpersicum), spearmint (Mentha spicata), horsemint (Menthalongifolia), coriander (Coriandrum sativum), sage (Salviaofficinalis), and ginger (Zingiber officinale) were evaluated. In 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, free radicalscavenging activities of clove and avishane shirazi EOswere 90.69% and 88.63%, respectively. In reducing powerassay, the EO of clove showed the highest reducingcapacity. The highest concentrations of total phenolics(66.01 mg and 44.81 mg GAE/gram sample) were alsodetected for the EOs of clove and avishane shirazi,respectively. The results of disc diffusion assay showedthat the EOs of avishane shirazi, cinnamon, and clovestrongly inhibited growth of the tested bacteria. The EO ofcinnamon had the lowest minimal inhibitory concentration(MIC) (0.312 mg/mL).

Correlation between Female Sex Hormones and Electrodiagnostic Parameters and Clinical Function in Post-menopausal Women with Idiopathic Carpal Tunnel Syndrome

( Azam Mohammadi ),( Mahshid Naseri ),( Hamid Namazi ),( Mohammad Javad Ashraf ),( Alireza Ashraf ) 대한폐경학회 2016 대한폐경학회지 Vol.22 No.2

Objectives: To investigate the role of sex-hormonal changes in idiopathic carpal tunnel syndrome (CTS) among post-menopausal women through measuring estrogen receptor (ER) expression in their transverse carpal ligament (TCL) and serum estrogen level, as well as determine the correlation between these factors and electrodiagnostic parameters and Boston score. Methods: Biopsy samples of TCL were collected from 12 postmenopausal women who had undergone surgery for severe idiopathic CTS; control specimens were collected from 10 postmenopausal women without CTS who had undergone surgery for the other hand pathologies. To determine the distributions of ER in TCL, histological and immunohistochemical examinations were performed. Serum estrogen level was also measured. Electrodiagnosis and Boston questionnaire were used for CTS severity and determination of the patients’ function. Results: ER expression in TCL and serum estrogen level were not significantly different in the case group compared to the control group (P = 0.79 and P = 0.88, respectively). Also, there was no correlation between ER expression or serum estrogen level and electrodiagnostic parameters or Boston score. Conclusions: Sex hormones cannot still be considered as the etiology of idiopathic CTS in postmenopausal women. The role of other factors such as wrist ratio and narrower outlet in females compared to the males should be considered along with hormonal changes. (J Menopausal Med 2016;22:80-86)

Comment on: COVID-19 and abortion right

Seyyed Javad Madani,Mohammad Mohammadi 대한산부인과학회 2021 Obstetrics & Gynecology Science Vol.64 No.3

Variation of the auditory system in the Indian Gerbil, Tatera indica Hardwicke, 1807, (Muridae, Rodentia) from the east of Iran

Asghar Khajeh,Zeinolabedin Mohammadi,Fatemeh Ghorbani,Javad Meshkani 국립중앙과학관 2019 Journal of Asia-Pacific Biodiversity Vol.12 No.2

The Indian Gerbil (Tatera indica) is one of the most successful species in the east of Iran regarding the population size and distributional range. Many factors are effective in the success of this species, but the tympanic bulla and external ear with a special role in increasing sensitivity could be very important. In this study, these two characters were examined in 108 skulls of the adult Indian Gerbil from different localities in the east of Iran. The results of this study show an increasing trend in the volume of tympanic bulla and length of external ear from higher to the lower latitudes in accordance with Allen's rule. This increase is significant in the southeast Iran population. The increase of the body size in the Indian Gerbil was also documented from the northeast toward the southeast Iran. The negative correlation between the body size and latitude implies thermoregulatory response of the Indian Gerbil to the cold climate of the northeast Iran. It can also reflect food scarcity in desert areas of the southeast Iran comparing with the northeast areas inhabiting by the Indian Gerbil. This study proposed that an increase in auditory sensitivity would be advantageous for the gerbil's ability to escape predation, to mate, and to compete for resources.

BRAF Mutations in Iranian Patients with Papillary Thyroid Carcinoma

Ranjbari, Nastran,Almasi, Sara,Mohammadi-asl, Javad,Rahim, Fakher Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.4

Background: Papillary thyroid cancer or papillary thyroid carcinoma (PTC) is the most common thyroid cancer. The fact that it occasionally occurs in women aged 30-40 years old suggests that genetic alterations are involved its genesis. Recently, activator mutations in BRAF gene have been relatively frequently discovered. Materials and Methods: In this study, we tested 63 DNA samples from PTC patients to identify the V600E mutation frequency in the Ahvaz population. DNA was isolated from formalin fixed paraffin-embedded (FFPE) PTC tumor tissues. Genotyping was performed by PCR-RFLP and confirmed by direct DNA sequencing of a subset of PCR products. PCR-RFLP data were reported as genotype frequencies and percentages. Results: Forty nine out of 63 patients (77.8%) had a mutated heterozygote form while 14 (22.2%) showed normal genotype but none demonstrated a mutant homozygote genotype. The frequency of V600E mutation was significantly high in PTC patients. Conclusions: These findings support involvement of V600E mutations in PTC occurrence in Iran. Assessment of correlations between BRAF V600E mutations and papillary thyroid cancer progression needs to be performed.