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کاربرد نوع شرط:
- جایگاه : پژوهشی
- مجله: Mechanics of Advanced Composite Structures
- نوع مقاله: Journal Article
- کلمات کلیدی: Nanocomposite,Pyrolysis,CNT,In situ formation,Silicon particles
- چکیده:
- چکیده انگلیسی: In this research, using pyrolysis of phenolic resin in the presence of silicon particles, the SiC ceramic composite is formed. The samples were prepared by introducing 30, 35, 40, 45 and 50 wt% of Si particles to the phenolic resin. The samples were cured at 180°C then carbonized at 1100°C. The final carbonized C/Si composites are hot-pressed at 1500°C in inert atmosphere, which is more than the melting point of Si particles. In this temperature, Carbon vapor and melted Si react and SiC ceramic is formed. The XRD analysis of samples showed that SiC peak was observed in the final product while carbonized phenolic and Si particles also existed in the matrix. The samples were so brittle and therefore, several impregnation processes should have been used to reduce the porosity of composite. SEM images of in situ composite reveal extraordinary phenomenon which is related to the formation of CNT and nanostructures on the base of Si particles that grow like flower in the matrix. These nanostructures are one of the reasons for higher mechanical properties of final nanocomposite. Three-point flexural tests are also conducted for better understanding of mechanical improvement.
- انتشار مقاله: 22-03-1393
- نویسندگان: Hamid Reza Salehi,Manouchehr Salehi
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Optoelectronical Nanostructures
- نوع مقاله: Journal Article
- کلمات کلیدی: Optical properties,Nanostructures,Chemical vapor deposition,GaN,Green method
- چکیده:
- چکیده انگلیسی: Gallium nitride (GaN) nanostructures (NS) were synthesized using pulsed
direct current plasma enhanced chemical vapor deposition (PDC-PECVD) on quartz
substrate at low temperature (600°C). Gallium metal (Ga) and nitrogen (N) plasma were
used as precursors. The morphology and structure of the grown GaN NS were
characterized by field emission scanning electron microscope (FE-SEM), transmission
electron microscopy (TEM) and X-ray diffraction (XRD). The XRD pattern shows that
GaN NS were grown in the hexagonal wurtzite-type crystal structure. The optical
properties of the grown GaN NS were examined by photoluminescence (PL), UVvisible
and Raman spectroscopy. The PL spectroscopy measurements of the grown GaN
NS showed blue shifts as compared to the GaN bulk structure. The Raman spectra
displayed three Raman active optical phonons at 534 cm-1, 570 cm-1 and 730 cm-1 due to
A1 (TO), E2 (high) and A1 (LO), respectively.- انتشار مقاله: 22-08-1396
- نویسندگان: Mahdi Gholampour,Amir Abdollah-zadeh,Leila Shekari,Reza Poursalehi,Mahdi Soltanzadeh
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Rehabilitation Sciences and Research
- نوع مقاله: Journal Article
- کلمات کلیدی: Low back pain, Lumbopelvic movement, Kinematics,Stair descending
- چکیده:
- چکیده انگلیسی: Background: Decreased lumbar spine control may be associated with early and/or excessive lumbopelvic motion with trunk and lower extremity movementsduring functional and daily activities. This study investigated differences inlumbopelvic movement patterns in people with and without low back pain(LBP) during a stair descending (SD) task.Methods: A total of 36 subjects, 18 females with non-specific chronic low backpain (NSCLBP) and 18 healthy females, participated in this study. A threedimensionalmotion capture system was used to record kinematics during theSD task.Results: The results showed that in the LBP group, the start-time of the lumbarmuscles occurred early in the movement (P=0.015). Additionally, subjects withLBP showed excessive lumbar spine and pelvic movement during the SD task(P<0.05).Conclusion: LBP patients make early and excessive lumbopelvic movementsduring a SD task, and this can be an important factor contributing to thedevelopment or persistence of their LBP problem. This finding should beconsidered by clinicians when evaluating functional tasks as part of movementbasedexaminations and rehabilitation programs for people with LBP.
- انتشار مقاله: 13-04-1397
- نویسندگان: Neda Namnik,Reza Salehi,Mohammad Jafar Shaterzadeh-Yazdi,Fatemeh Esfandiarpour,Mohammad Mehravar,Neda Orakifar
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Rehabilitation Sciences and Research
- نوع مقاله: Journal Article
- کلمات کلیدی: classification,Low back pain,Surface electromyography,Recruitment pattern
- چکیده:
- چکیده انگلیسی: Background: While various studies have examined motor control differences between subjects with and without low back pain (LBP), only a few have investigated the muscle recruitment pattern in classified LBP patients during functional activity. The aim of this study was to investigate the firing pattern of the main muscles involved in sit-to-stand (STD) and stand-to-sit (STS) tasks in two prevalent LBP subgroups based on movement system impairment (MSI) classification. Methods: A total of 37 women between 18 and 50 years of age voluntarily participated in this cross-sectional study. They were divided into three groups (15 healthy, 15 lumbar extension rotation syndrome (LERS), and seven lumbar flexion rotation syndrome (LFRS)). Surface electromyography was recorded bilaterally from the trunk stabilizer muscles—i.e. the internal oblique (IO), lumbar erector spine (ES), and hip mobilizer muscles—and the medial (MH) and lateral (LH) hamstring muscles during STD and STS tasks. The variations in EMG onset muscle timing and asymmetry in side-to-side muscle timing were measured. Results: The firing sequence during the STD task showed no significant difference among groups. However, in the healthy and LFR groups the trunk stabilizer muscles were activated before the hip mobilizer muscles, and in the LERS group an insignificant delay was shown in the onset of the ES activity. There was no significant difference of bilateral muscle timing during STD. In the STS task no consistent order of pattern was found even in the healthy group. The bilateral muscle timing of IO (mean difference, -427.00; P=0.021) and ES (mean difference, 1964.57; P=0.000) had significant difference in the LFRS group during STS. Conclusion: The cumulative effects of recruitment pattern impairment may contribute to continuing the cycle of lumbar movement impairments and subsequent persistence of LBP.
- انتشار مقاله: 13-02-1397
- نویسندگان: Neda Orakifar,Mohammad Jafar Shaterzadeh-Yazdi,Reza Salehi,Mohammad Mehravar,Neda Namnik
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Nutrition,Fasting and Health
- نوع مقاله: Journal Article
- کلمات کلیدی: diabetes,Training,Genistein,TNF-α,BDNF
- چکیده:
- چکیده انگلیسی: Introduction: As physical education and nutrition are two effective factors in management of diabetes, the purpose of this study was to investigate the effect of moderate intensity endurance training and genistein on serum levels of brain-derived neurotrophic factor (BDNF) and tumor necrosis factor-α (TNF-α) in diabetic rats. Methods: In this experimental study, 40 diabetic rats were selected and divided into five groups: (1) control; (2) moderate intensity endurance training; (3) genistein consumption; (4) moderate intensity endurance training with genistein and (5) sham. Rats in groups 2 and 4 ran on treadmill for eight weeks, three sessions per week, and each session for 60 minutes at speeds of 10- 17 m/min, and rats in groups 3 and 4 received daily 30 mg/kg genistein intraperitoneal injection. Kolmogorov-Smirnov test, independent sample t- test and two-way ANOVA were used to analyze the findings (p≤0.05).
Results: Endurance training had a significant effect on increasing BDNF (P=0.002 and effect size, 0.34) and reducing TNF-α (p = 0.003 and effect size, 0.31), genistein consumption had a significant effect on increasing BDNF (p = 0.01 and effect size, 0.24) and reducing TNF-α (p = 0.001 and effect size, 0.37); also, endurance training with genistein consumption had interactive effects on increasing BDNF (p = 0.04 and effect size, 0.15) and decreasing TNF-α (P = 0.019 and effect size, 0.20). Conclusion: It seems that moderate intensity training and genistein consumption alone can improve the BDNF and TNF-α in diabetic rats; nevertheless simultaneous consumption of genistein can accelerate the effects of moderate intensity training on improvement of BDNF and TNF-α in diabetic rats.- انتشار مقاله: 07-10-1397
- نویسندگان: Omid Reza Salehi,Seyed Ali Hosseini,Fatemeh Farkhaie,Parvin Farzanegi,Abdossaleh Zar
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Kerman University of Medical Sciences
- نوع مقاله: Journal Article
- کلمات کلیدی: fennel,Bleomycin,Pulmonary Fibrosis
- چکیده:
- چکیده انگلیسی: Background & Aims: Idiopathic pulmonary fibrosis (IPF) is a chronic diffuse interstitial lung disease,
which has symptoms such as coughing and shortness of breath. The average survival duration in these
patients is estimated as 3 years after the onset of symptoms. Today, the therapeutic approach used in IPF
cases is the usage of chemical or herbal antioxidants in order to eliminate free radicals and prevent
inflammation and fibrosis. Considering the antioxidant properties of fennel, this research was conducted to
investigate the effect of the methanol extracted of fennel on bleomycin-induced pulmonary fibrosis in rats.
Methods: To induce pulmonary fibrosis in rats, intratracheal administration of 15 mg bleomycin was
conducted in 52 male rates. Subsequently, the rats were injected intraperitoneally with 500 mg/(kg body
weight) of methanol extract of fennel 14-day and 28-day periods. The samples were studied in terms of
inflammation, fibrosis, hydroxyproline concentration, lipid peroxidation, and the catalase activity of lung
tissue. The obtained results were analyzed using SPSS software.
Results: The degree of inflammation, fibrosis, hydroxyproline and lipid peroxidation concentration in lung
tissue in the fennel methanol extract group had significantly decreased compared to other groups. In addition,
a significant increase was observed in tissue catalase concentration in this group in comparison to other
groups on days 14 and 28.
Conclusion: The obtained results illustrated that the methanol extract of fennel may be efficient in the
prevention and treatment of pulmonary fibrosis due to its antioxidant properties. Accordingly, it can be
suggested for the prevention and treatment of pulmonary fibrosis instead of corticosteroids and
immunosuppressant drugs due to their many side effects and most patients’ preference of herbal medicines.- انتشار مقاله: 23-04-1395
- نویسندگان: Mitra Samareh-Fekri,Hamid-Reza Poursalehi,Ali Mandegary,Fariba Sharififar,Rahil Mahmoudi,Atefe Izadi,Mohamad-Hadi Nematolahi,Nasrollah Jamshidi,Fatemeh Pourgholamhossein,Mohammad-Reza Lashkarizadeh
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Midwifery and Reproductive Health
- نوع مقاله: Journal Article
- کلمات کلیدی: Vaginal delivery,Abdominal pain,Bladder rupture,Renal dysfunction
- چکیده:
- چکیده انگلیسی: Background:Spontaneous bladder rupture is a rare condition, and almost all the reported cases in the world have been preceded by bladder dysfunction, radiotherapy, urinary tract obstruction, pelvic surgery, inflammation, and malignancy.
Case report: In this study, we present the case of a 39-year-old woman (G: 4, P: 1, Ab: 2) who was in week 38 of pregnancy and attended our hospital with the onset of labor pain. She gave birth to a 3200 g infant through normal vaginal delivery. The patient attended with severe abdominal pain and oliguria four days after delivery. Ultrasonography showed massive abdominal fluid and bladder rupture.
Conclusion: Regarding the rareness of bladder rupture during vaginal delivery, we introduced a case of bladder rupture following delivery. This case is important for midwives and gynecologists to gain more information about normal vaginal delivery complications to accelerate diagnostic and therapeutic interventions.- انتشار مقاله: 02-05-1396
- نویسندگان: Hamed Jafarpour,Alireza Salehi,Arash Rezaei Shahmirzadi,Sara Sadr,Aghdas Ebadi
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Herbal Drugs
- نوع مقاله: Journal Article
- کلمات کلیدی: Traditional Persian Medicine,Neonatal Jaundice,Cotoneaster mann,Purgative manna
- چکیده: زمینه و هدف: در طب سنتی از شیر خشت به عنوان یک روش درمانی به صورت سنتی در طب ایرانی برای درمان زردی نوزادان استفاده میشود. با استفاده از متا آنالیز و مرور متون، اثر شیر خشت بر زردی نوزادان بررسی شد.
روش تحقیق: هدف از این مطالعه بررسی اثر کارآزمایی های بالینی انجام شده در مورد شیرخشت بر زردی نوزادان است. شیوه اصلی که در این مطالعه استفاده شده شامل جستجو مقالات انگلیسی و فارسی تا مارچ 2016 بوده است. کیفبت کارآزمایی های بالینی با استفاده از چک لیست کانسورت برای مداخلات دارویی بررسی شد. هفت مطالعه که دارای تورش پایین یا متوسط بوده اند با 804 شرکت کننده برابر با 410 مورد در برابر 394 شاهد برای ورود به مطالعه مروری و یا متا آنالیز با نرم افزار CMA نسخه 2.2 انتخاب شدند.
نتایج: مقدار کلی بیلی روبین پلاسما در 0، 12، 24 ، 36، 48 ساعت و طول دوره اقامت در بیمارستان کنترل شده و هیچگونه عارضه جانبی گزارش نشده است. متاآنالیز نشان دهنده هتروژنیتی برجسته ای از نتایج بوده است(Q-value = 132.446, P< 0.0001, I2 = 87.165, τ = 0.998). با این حال، اثرات موثر شیرخشت بر زردی نوزادان نشان داده شده است(n= 804, OR = 0.242, 95% CI: 0.147 to 0.399, P < 0.0001). همچنین میتوان اذعان نمود که شیر خشت میتواند مدت اقامت در بیمارستان را نیز کاهش دهد(n= 804, SMD= -1.154, 95% CI: -1.854 to -0.455, P< 0.001). با این حال نتایج به دست آمده هتروژن و ناهمگن بوده است(Q-value= 119.642, P< 0.0001, I2= 94.985, τ= 0.913).
توصیه های کاربردی/ صنعتی: گرچه که متاآنالیز شیر خشت بر زردی نوزدان نشان دهنده اثر مثبت شیرخشت بر زردی نوزادان در این مطالعات بوده، با این حال انجام مطالعات چند مرکزی کارآزمایی بالینی با حجم نمونه بالاتر که برای عوامل خطر کنترل شده و مقایسه آن با روش درمان رایج که فتوتراپی می باشد توصیه میشود.- چکیده انگلیسی: Background & Aim: The manna of Cotoneaster nummularia (purgative manna) has been traditionally used in the Persian medicine for the treatment of neonatal jaundice. The effect of Cotoneaster manna on neonatal jaundice was investigated with systematic review and meta-analysis.
Experimental: This study intended to explore the clinical trials of the efficacy of Cotoneaster manna on neonatal jaundice. The aspects considered in this study included searching for relevant English and Persian data bases up to March 2016. The methodological quality was assessed using the Consort checklist for herbal interventions. Seven studies with low or moderate risk of bias involved 804 participants of which 410 cases versus 394 controls were selected for systematic review and meta-analysis with CMA software version 2.2.
Results: Total plasma bilirubin in 0, 12, 24, 36, 48 hours and the duration of hospital stay were checked and no adverse effect was reported. The Meta-analysis exhibited marked heterogeneity of the results (Q-value = 132.446, P< 0.0001, I2 = 87.165, τ = 0.998). However, it showed favorable effect of Cotoneaster manna on reducing neonatal jaundice (n= 804, OR = 0.242, 95% CI: 0.147 to 0.399, P< 0.0001). Also it was effective on reducing duration of hospital stay (n= 804, SMD= -1.154, 95% CI: -1.854 to -0.455, P< 0.001). However, the results obtained were heterogeneous (Q-value= 119.642, P< 0.0001, I2= 94.985, τ= 0.913).
Recommended applications/ industries: Although the meta-analysis of Cotoneaster manna showed positive effect on treatment of neonatal jaundice in these studies, it is warranted to carry out further multi-centre randomized clinical trials with larger samples and controlled risk factors, alongside comparison with phototherapy.- انتشار مقاله: 11-10-1348
- نویسندگان: Alireza Salehi,Mohadeseh Ostovar,Maryam Marzban
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Computational Applied Mechanics
- نوع مقاله: Journal Article
- کلمات کلیدی: dynamic model,physical model,IPMC,Smart Materials
- چکیده:
- چکیده انگلیسی: By the past two decades IPMCs have been intensively studied because of their special capabilities for actuation and sensing.This paper presents a theoretical physics based model for analyzing the behavior of IPMC sensors in fluid environments. The mechanical vibration of the IPMC strip is described by the classical Euler–Bernoulli beam theory. The model also takes in to account the physical properties of the surrounding fluid. The resulting model is an infinite-dimensional transfer function that relates the input tip displacement to the output sensing current. Further the original model is reduced to a finite-dimensional one, for pure sensing applications of IPMC sensors such as structural health monitoring. The proposed model is verified using existing experimental data. Then the effect of various parameters is investigated. The acoustics physics interface in COMSOL Multiphysics software is used for coupled modal analysis of the IPMC strip. It is shown that the effect of surrounding fluid cannot be neglected.
- انتشار مقاله: 10-03-1398
- نویسندگان: Mohammad Reza Salehi Kolahi,Hossein Moeinkhah
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Advances in Medical Education and Professionalism
- نوع مقاله: Journal Article
- کلمات کلیدی: Questionnaire,Factor analysis,Medical students,reliability,Skills
- چکیده:
- چکیده انگلیسی: Introduction: Bedside teaching plays a crucial role in acquiring essential clinical skills. Therefore, the main aim of this study is assessing the validity and reliability of the Persian version of German bedside teaching (BST) instrument. This instrument was specially developed for evaluation of bedside teaching.
Methods: The present cross-sectional study was conducted on 150 last year medical students, using convenience sampling. The Persian version of the bedside teaching (BST) was used for data
gathering. To calculate the reliability of the questions, Cronbach’s alpha was used and to determine the construct validity of the questionnaire, confirmatory factor analysis was used. All analyses
were performed in LISREL 10 and SPSS 21 software.
Results: Cronbach’s alpha indicated excellent reliability for each subscale (α=0.77–0.85). All of the value of the questions are more than a significant number of 1.96 and concluded to be significant. There was an acceptable fit between the hypothetical model and the data and all comparative fit indices (CFI, NFI, RFI, IFI) showed good model fitness. BST is a valid and reliable instrument for the assessment of clinical teaching at bedside. It has 18 items with 5 point Likert scales.
Conclusion: The findings suggest that the Persian version of the BST questionnaire is a valid and reliable tool for the evaluation of teachers and providing feedback in a clinical setting. However,
more studies should be conducted in other cities in Iran.- انتشار مقاله: 30-04-1399
- نویسندگان: MOHAMMAD SAEED GHARAATI JAHROMI,MITRA AMINI,MAHSA MOOSAVI,ALIREZA SALEHI,SOMAYEH DELAVARI,ALI ASGHAR HAYAT,PARISA NABEIEI
- مشاهده