Effects of discrete source-sink arrangements on mixed convection in a square cavity filled by nanofluid

Mohsen Izadi,Amin Behzadmehr,Mohammad Mohsen Shahmardan 한국화학공학회 2014 Korean Journal of Chemical Engineering Vol.31 No.1

Laminar mixed convection of Al2O3/water nanofluid flow in a cavity in which the upper wall is moving from right to left has been studied numerically. Fifteen different arrangements of two discrete sources and four discrete sinks have been considered. This work shows when one source is located at the right side of the bottom wall and other one at the down half of the left wall, total heat transfer achieves its maximum value. The lowest heat transfer rate is achieved when more than two vortexes are created in the cavity (case 13 for Ri=1 and case 5 for Ri=100). In general,for cases with one overall vortex, the cavities which have separate sources induce better cooling and have higher Nu number.

Horizontal instability after acromioclavicular joint reduction using the two-hole technique is preferred over the loop technique: a single-blind randomized clinical trial

Mohsen Mardani-Kivi,Kamran Asadi,Ehsan Kazemnejad Leili,Keyvan Hashemi-Motlagh,Amin Izadi,Mona Pishgahpour,Zohre Darabipour 대한견주관절학회 2022 대한견주관절의학회지 Vol.25 No.3

Background: Most acromioclavicular joint (ACJ) injuries are caused by direct trauma to the shoulders, and various methods and techniques are used to treat them; however, none of the options can be considered the gold standard. This study examines the horizontal stability of the ACJ after a complete dislocation was repaired using one of two Ethibond suture techniques, the loop technique and the two holes in the clavicle technique. Methods: In this single-blind, randomized clinical trial, 104 patients diagnosed with complete ACJ dislocation type V were treated using Ethibond sutures with either the loop technique or the two holes in the clavicle technique. Horizontal changes in the ACJ were radiographically assessed in the lateral axial view, and shoulder function was evaluated by the Constant (CS) and Taft (TS) scores at intervals of 3, 6, and 12 months after surgery. Results: The horizontal stability of the ACJ was better with the two-hole technique than the loop technique at all measurement times. CS and TS changes showed a significant upward trend over time with both techniques. The mean CS and TS at the final visit were 95.2 and 11.6 with the loop technique and 94.0 and 11.9 with the two-hole technique, respectively. The incidence of superficial infections caused by the subcutaneous pins was the same in the two groups. Conclusions: Due to the improved ACJ stability with the two-hole technique, it appears to be a more suitable option than the loop technique for AC joint reduction.

An implicit rheological model for numerical simulation of generalized Newtonian fluids

Mohsen Lashkarbolok,Shukoofeh Izadi,Hadi Alemi,Sita Drost 한국유변학회 2015 Korea-Australia rheology journal Vol.27 No.2

Fitting an explicit curve over some discrete data extracted from a rheometer is the usual way of writing a rheological model for generalized Newtonian fluids. These explicit models may not match totally with the extracted data and may ignore some features of the rheological behavior of the fluids. In this paper, a cubicspline curve fitting is used to fit a smooth curve from discrete rheological data. Spline interpolation avoids the problem of Runge's phenomenon, which occurs in interpolating using high degree polynomials. The formulation for applying presented rheological model is described in the context of least squares meshfree technique. One problem is solved to show validity of the scheme: a fluid with rather complex rheology model is considered and solved by both conventional explicit and proposed implicit models to show the advantages of the presented method

Evaluating Direct Costs of Gastric Cancer Treatment in Iran - Case Study in Kerman City in 2015

Izadi, Azar,Sirizi, Mohammad Jaffari,Esmaeelpour, Safa,Barouni, Mohsen Asian Pacific Journal of Cancer Prevention 2016 Asian Pacific journal of cancer prevention Vol.17 No.6

Background: Gastrointestinal cancers are common malignancies associated with high mortality rates. Healthcare systems are always faced with high costs of treatment of gastrointestinal cancers including stomach cancer. Identification and prioritization of these costs can help determine economic burden and then improve of health planning by policy-makers. This study was performed in 2015 in Kerman City aimed at estimating the direct hospital costs for patients with gastric cancer. Materials and Methods: In this cross-sectional study, the medical records of 160 patients with stomach cancer admitted from 2011 to 2014 to Shafa Hospital were examined, the current stage of the disease and the patients' health status were identified, and the direct costs related to the type of treatment in the public and private sectors were calculated. SPSS-19 was used for statistical analysis of the data. Results: Of the patients studied, 103 (65%) were men and 57 (35%) were women. The mean age of patients was 65 years. Distribution into four stages of the disease was 5%, 20%, 30%, and 45%, respectively. Direct costs in four stages of the disease were calculated as 2191.07, 2642.93, 2877, and 2674.07 USD (63,045,879, 76,047,934, 82,783,019, and 76,943,800 IRR), respectively. The highest percentage of costs was related to surgery in Stage I and to medication in Stages II, III, and IV. According to the results of direct costs of treatment for stomach cancer in Kerman, the mean total cost of treating a patient in the public sector was estimated at 74,705,158 IRR, of which averages of 60,141,384 IRR and 14,563,774 IRR were the shares of insurance and patients, respectively. Conclusions: The high prevalence and diagnosis of disease in old age and at advanced stages of disease impose great costs on the patients and the health system. Early diagnosis through screening and selecting an appropriate treatment method might largely ameliorate the economic burden of the disease.

Rotator cuff repair with or without proximal end detachment for long head of the biceps tendon tenodesis

Mardani-Kivi, Mohsen,Asadi, Kamran,Izadi, Amin,Leili, Ehsan Kazemnejad Korean Shoulder and Elbow Society 2022 대한견주관절의학회지 Vol.25 No.2

Background: Rotator cuff tears cause pathologies of the long head of the biceps tendon (LHBT). One of the surgical treatments for such a tear is LHBT tenodesis to the humerus. This study aims to compare simultaneous rotator cuff repair and LHBT tenodesis with or without detachment of the proximal end of the LHBT (PELHBT) from its site of adhesion to the glenoid. Methods: This retrospective study involved patients affected by LHBT pathology with rotator cuff tear. The patients were divided into two groups, with or without PELHBT detachment from the glenoid. Therapeutic outcomes were investigated by evaluation of patient satisfaction, pain based on visual analog scale, shoulder function based on Constant score and simple shoulder test, and biceps muscle strength based on the manual muscle testing grading system before surgery, at 6 months, and at the final visit after surgery. Results: Groups 1 and 2 comprised 23 and 26 patients, respectively, who showed no significant differences in demographic characteristics (p>0.05). Shoulder function, biceps muscle strength, pain, and satisfaction rate improved over time (p<0.05) but were not significantly different between the two groups (p>0.05). No post-surgical complication was found in either group. Conclusions: There was no difference in final outcomes of tenodesis with or without detachment of the PELHBT from the supraglenoid tubercle. Such tendon detachment is not necessary.

Can indirect magnetic resonance arthrography be a good alternative to magnetic resonance imaging in diagnosing glenoid labrum lesions?: a prospective study

Mardani-Kivi, Mohsen,Alizadeh, Ahmad,Asadi, Kamran,Izadi, Amin,Leili, Ehsan Kazemnejad,arzpeyma, Sima Fallah Korean Shoulder and Elbow Society 2022 대한견주관절의학회지 Vol.25 No.3

Background: This study was designed to evaluate and compare the diagnostic value of magnetic resonance imaging (MRI) and indirect magnetic resonance arthrography (I-MRA) imaging with those of arthroscopy and each other. Methods: This descriptive-analytical study was conducted in 2020. All patients who tested positive for labrum lesions during that year were included in the study. The patients underwent conservative treatment for 6 weeks. In the event of no response to conservative treatment, MRI and I-MRA imaging were conducted, and the patients underwent arthroscopy to determine their ultimate diagnosis and treatment plan. Imaging results were assessed at a 1-week interval by an experienced musculoskeletal radiologist. Image interpretation results and arthroscopy were recorded in the data collection form. Results: Overall, 35 patients comprised the study. Based on the kappa coefficient, the results indicate that the results of both imaging methods are in agreement with the arthroscopic findings, but the I-MRA consensus rate is higher than that of MRI (0.612±0.157 and 0.749±0.101 vs. 0.449±0.160 and 0.603±0.113). The sensitivity, specificity, negative predictive value, positive predictive value, and accuracy of MRI in detecting labrum tears were 77.77%, 75.00%, 91.30%, 50.00%, and 77.14%, respectively, and those of I-MRA were 88.88%, 75.00%, 92.30%, 66.66%, and 85.71%. Conclusions: Here, I-MRA showed higher diagnostic value than MRI for labral tears. Therefore, it is recommended that I-MRA be used instead of MRI if there is an indication for potential labrum lesions.

Comparison Between Two Detection Methods for HPV16, HPV18 and P16Ink4a Biomarkers in Diagnosis of Abnormal Cervical Cytology

Khazaei, Sedigheh,Izadi, Babak,Mirbahari, Seyed Ghasem,Madani, Seyed Hamid,Khosravi, Shohre Malek,Alagha, Mohsen Emami,Sajadimajd, Soraya Asian Pacific Journal of Cancer Prevention 2016 Asian Pacific journal of cancer prevention Vol.17 No.12

Background: Cervical cancer is the second most common cancer among women in many populations. While the Pap smear is a well established screening test it suffers from both false-positive and false-negative results in diagnosis of cancers and precancerous states. In this study, immunocytochemistry of the P16 biomarker and HPV-PCR were compared for their diagnostic potential. Materials and methods: In the study, we obtained pairs of specimens from 45 women with cervical dysplasia. One sample was placed in a liquid-based solution, and processed for staining of sections with antibodies to P16. HPV-PCR was performed on the other and the results obtained were analyzed by T-test using SPSS v. 15. Results: Using HPV-PCR 71% of the samples were found to be infected with either HPV 16 or HPV 18, and the rate of infection did not have a statistically significant relationship with higher grades of dysplasia (p= 0.253). In contrast, with immunocytochemistry evaluation of P16, 64% of the specimens were positive, but the percentage of positive results significantly increased with higher grades of dysplasia (p= 0.0001). Conclusion: Employment of the P16 marker as an optional test might be preferable over HPV-PCR for cervical dysplasia in our geographical region.

Air pollution study using factor analysis and univariate Box-Jenkins modeling for the northwest of Tehran

Asadollahfardi, Gholamreza,Zamanian, Mehran,Mirmohammadi, Mohsen,Asadi, Mohsen,Tameh, Fatemeh Izadi Techno-Press 2015 Advances in environmental research Vol.4 No.4

High amounts of air pollution in crowded urban areas are always considered as one of the major environmental challenges especially in developing countries. Despite the errors in air pollution prediction, the forecasting of future data helps air quality management make decisions promptly and properly. We studied the air quality of the Aqdasiyeh location in Tehran using factor analysis and the Box-Jenkins time series methods. The Air Quality Control Company (AQCC) of the Municipality of Tehran monitors seven daily air quality parameters, including carbon monoxide (CO), Nitrogen Monoxide (NO), Nitrogen dioxide ($NO_2$), $NO_x$, ozone ($O_3$), particulate matter ($PM_{10}$) and sulfur dioxide ($SO_2$). We applied the AQCC data for our study. According to the results of the factor analysis, the air quality parameters were divided into two factors. The first factor included CO, $NO_2$, NO, $NO_x$, and $O_3$, and the second was $SO_2$ and $PM_{10}$. Subsequently, the Box- Jenkins time series was applied to the two mentioned factors. The results of the statistical testing and comparison of the factor data with the predicted data indicated Auto Regressive Integrated Moving Average (0, 0, 1) was appropriate for the first factor, and ARIMA (1, 0, 1) was proper for the second one. The coefficient of determination between the factor data and the predicted data for both models were 0.98 and 0.983 which may indicate the accuracy of the models. The application of these methods could be beneficial for the reduction of developing numbers of mathematical modeling.