Chronic Extrahepatic Bile Duct Dilatation: Sonographic Screening in the Patients with Opioid Addiction

H. Farahmand,M. PourGholami,M. Sheikh Fathollah 대한영상의학회 2007 Korean Journal of Radiology Vol.8 No.3

Objective: One of the best known side effects of using opium is spasm of the sphincter of Oddi, which may increase the diameter of the extrahepatic bile ducts. Ultrasound is the first imaging modality used for evaluating the biliary system because it is commonly available and noninvasive. The principal objective of this study was to measure the common bile duct (CBD) diameter via ultrasonography in opium addicts and to evaluate the relation between the CBD diameter and the period of addiction. Materials and Methods: This research was an analytical-cross sectional study that was done on 110 opium addicts that were admitted to a drug treatment center. The diameter of the CBD in these cases was measured by ultrasonography and the results were analyzed with other factors like age, the period of addiction and the laboratory findings. Results: According to the findings, there is a significant increase in the range of the CBD diameter in comparison with normal bile ducts. Also, the mean diameter of the CBD in the different age groups showed a significant difference (p < 0.0001) and there was a significant relation between the CBD diameter and the period of addiction (p < 0.001, r = 0.74); so, with the increased length of the addiction period, the mean CBD diameter increases. Conclusion: Opium addiction is one of the factors that causes extrahepatic bile duct dilatation, so in these cases, if no obstructing lesion was found on ultrasound examination and the serum bilirobine and alkaline phosphatase levels are normal, then further evaluation is not needed.

Investigation of the Progressive Collapse in a Suspension Bridge Under the Explosive Load

Salar Farahmand-Tabar,Majid Barghian,Majid Vahabzadeh 한국강구조학회 2019 International Journal of Steel Structures Vol.19 No.6

Progressive collapse is a continuous spread of initial local failure from one member to another one, fi nally causing the collapse of the structure entirely or a disproportionately large part of it. This disproportionate collapse is due to the small initial local failure induced by unpredicted attacks, exhibiting that the structural system cannot resist the development of damage due to the insuffi cient load carrying capacity. In this study, a typical suspension bridge was modeled and analyzed under explosion load. For this purpose, diff erent scenarios were investigated. Forces and moments of the superstructure, responses and the stability of the structure under the applied loads were studied. Explosion applied on the structure depends on the amount of the load and local eff ects. Also, by removing one or several elements of structures, the force is distributed in the whole structure. For loading rate on diff erent positions of the structure, it was observed that the critical position would be under the explosion and towers adjacent. Towers adjacent and the middle of the deck were prone to the maximum infl uences where should be put more attention on and be reinforced to preserve the structure from the total and local failure.

An efficient simulation method for reliability analysis of systems with expensive-to-evaluate performance functions

Bahman Farahmand Azar,Ali Hadidi,Amin Rafiee 국제구조공학회 2015 Structural Engineering and Mechanics, An Int'l Jou Vol.55 No.5

This paper proposes a novel reliability analysis method which computes reliability index, most probable point and probability of failure of uncertain systems more efficiently and accurately with compared to Monte Carlo, first-order reliability and response surface methods. It consists of Initial and Simulation steps. In Initial step, a number of space-filling designs are selected throughout the variables space, and then in Simulation step, performances of most of samples are estimated via interpolation using the space-filling designs, and only for a small number of the samples actual performance function is used for evaluation. In better words, doing so, we use a simple interpolation function called “reduced” function instead of the actual expensive-to-evaluate performance function of the system to evaluate most of samples. By using such a reduced function, total number of evaluations of actual performance is significantly reduced; hence, the method can be called Reduced Function Evaluations method. Reliabilities of six examples including series and parallel systems with multiple failure modes with truncated and/or non-truncated random variables are analyzed to demonstrate efficiency, accuracy and robustness of proposed method. In addition, a reliabilitybased design optimization algorithm is proposed and an example is solved to show its good performance.

Seismic Performance of Composite RCS Special Moment Frames

Bahman Farahmand Azar,Hosein Ghaffarzadeh,Nima Talebian 대한토목학회 2013 KSCE Journal of Civil Engineering Vol.17 No.2

Composite Reinforced Concrete-Steel (RCS) frames which consist of Reinforced Concrete (RC) columns and Steel (S) beams were represented to combine the advantages of pure RC and steel frames. This system permits the primary steel beam to run continuous through the reinforced concrete column. This paper evaluates seismic performance of RCS frames based on FEMA-356,considering plastic rotations as acceptance criteria. The effect of joint deformations on overall behavior of RCS frames is studied through nonlinear static analysis (Pushover) that is performed in OpenSees software. It is concluded that the RCS joint behavior increases lateral load capacity of frame. Additionally, 3 RC frames are compared to RCS frames with columns similar to those of RC frames. The results show a great improvement on overall behavior since steel beams is used instead of RC beams.

Effect of the height of SCSW on the optimal position of the stiffening beam considering axial force effect

B. Farahmand Azar,A. Hadidi,H. Khosravi 국제구조공학회 2012 Structural Engineering and Mechanics, An Int'l Jou Vol.41 No.2

Stiffened coupled shear walls (SCSW) are under axial load resulting from their weight and this axial load affects the behavior of walls because of their excessive height. In this paper, based on the continuum approach, the optimal position of the stiffening beam on the stiffened coupled shear walls is investigated considering the effect of uniformly distributed axial loads. Moreover, the effect of the height of stiffened coupled shear walls on the optimal position of the stiffening beam has been studied with and without considering the axial force effect. A computer program has been developed in MATLAB and numerical examples have been solved to demonstrate the reliability of this method. The effects of the various flexural rigidities of the stiffening beam on the internal forces and the lateral deflection of the structure considering axial force effect have also been investigated.

Optimal Design of MR Damper Based on Tuning Bouc-Wen Model Parameters Using Hybrid Algorithms

Bahman Farahmand Azar,Hedayat Veladi,Siamak Talatahari,Farzad Raeesi 대한토목학회 2020 KSCE JOURNAL OF CIVIL ENGINEERING Vol.24 No.3

This paper presents a useful approach to optimally design magnetorheological (MR) dampers used in structural buildings. To fulfill this aim, damper parameters are regarded as the design variables whose values can be obtained through an optimization process. To improve the quality of searching for the optimum parameters of MR dampers, charged system search (CSS) and grey wolf (GW) algorithms, two of the most widely utilized meta-heuristic algorithms, are used together, and hybrid CSS-GW is presented. To show the authenticity and robustness of the new algorithm in solving optimization problems, some benchmark test functions are tested, at first. Then, an eleven-story benchmark building equipped with 3 MR dampers is considered to get the optimum design of the MR damper using the hybrid CSS-GW. Results show that the developed hybrid algorithm can successfully figure out the optimum parameters of the MR dampers.

Cow`s Milk Allergy among Children with Gastroesophageal Reflux Disease

( Fatemeh Farahmand ),( Mehri Najafi ),( Pedram Ataee ),( Vajiheh Modarresi ),( Turan Shahraki ),( Nima Rezaei ) 대한소화기기능성질환·운동학회 2011 Gut and Liver Vol.5 No.3

Background/Aims: Gastroesophageal reflux disease (GERD) and cow`s milk allergy (CMA) are two common conditions that occur in infancy. This study was performed to investigate the frequency of CMA in a group of patients with GERD. Methods: Eighty-one children with signs and symptoms of GERD were enrolled in this study. All subjects received omeprazole for 4 weeks after the initial evaluation. Empirical elimination of cow`s milk from the diet was started for the patients who did not respond to the omeprazole treatment. Results: Seventy-two cases presented with gastrointestinal signs and symptoms, whereas the remaining nine cases presented with respiratory complaints. After the initial treatment with omeprazole, two thirds of the cases (54 patients, 66.7%) responded well, and all of their symptoms were resolved. Cow`s milk was eliminated from the diets of the remaining 27 patients. All signs and symptoms of GERD were resolved in this group after a 4 week elimination of cow`s milk from the diet. Conclusions: A diagnosis of CMA was considered in one third of the pediatric cases with signs and symptoms of GERD. This finding shows that CMA can mimic or aggravate all signs and symptoms of severe GERD during infancy. (Gut Liver 2011;5:298-301)

ORiginal Article : Gastroesophageal Reflux Disease and Tooth Erosion; A Cross-Sectional Observational Study

( Fatemeh Farahmand ),( Mozhgan Sabbaghian ),( Sharareh Ghodousi ),( Nasila Seddighoraee ),( Mahdi Abbasi ) The Editorial Office of Gut and Liver 2013 Gut and Liver Vol.7 No.3

Background/Aims: Gastroesophageal reflux disease (GERD) is common in children. Recurrent exposure to gastric acid in GERD may contribute to tooth erosion. Methods: In this prospective study, 54 GERD patients qualified according to endoscopy, pH-metry, and the GERD questionnaire and 58 healthy controls qualified by the GERD questionnaire were assessed. Two groups underwent dental evaluations for the presence, severity, and patterns of erosion and for the stage of dentition using a Tooth Wear Index. The health care providers who performed the dental exams did not know which children had been diagnosed with GERD. Results: A total of 112 children, 3 to 12 years old were enrolled in the study, and 53 of 54 (98.1%) GERD patients and 11 of 58 (19.0%) controls had dental erosions (p<0.0001). In GERD patients, the posterior occlusal surfaces of milk teeth were more affected (p<0.0001). There was no correlation between GERD and the affected surfaces in permanent teeth, nor in the patterns or erosion grades (localized or general). In both groups, milk teeth had more erosions than permanent teeth, but the difference was not statistically significant. Conclusions: According to this study, there is a positive correlation between GERD and dental erosion. Posterior occlusal surface erosions in milk teeth could indicate GERD. (Gut Liver 2013; 7:278-281)

Effect of the height of SCSW on the optimal position of the stiffening beam considering axial force effect

Azar, B. Farahmand,Hadidi, A.,Khosravi, H. Techno-Press 2012 Structural Engineering and Mechanics, An Int'l Jou Vol.41 No.2

Stiffened coupled shear walls (SCSW) are under axial load resulting from their weight and this axial load affects the behavior of walls because of their excessive height. In this paper, based on the continuum approach, the optimal position of the stiffening beam on the stiffened coupled shear walls is investigated considering the effect of uniformly distributed axial loads. Moreover, the effect of the height of stiffened coupled shear walls on the optimal position of the stiffening beam has been studied with and without considering the axial force effect. A computer program has been developed in MATLAB and numerical examples have been solved to demonstrate the reliability of this method. The effects of the various flexural rigidities of the stiffening beam on the internal forces and the lateral deflection of the structure considering axial force effect have also been investigated.

Evaluation of Cyc1 protein stability in Acidithiobacillus ferrooxidans bacterium after E121D mutation by molecular dynamics simulation to improve electron transfer

Shojapour Mahnaz,Farahmand Somayeh,Fatemi Faezeh,Shasaltaneh Marzieh Dehghan 한국미생물학회 2022 The journal of microbiology Vol.60 No.5

Cyc1 (Cytochrome c552) is a protein in the electron transport chain of the Acidithiobacillus ferrooxidans (Af) bacteria which obtain their energy from oxidation Fe2+ to Fe3+. The electrons are directed through Cyc2, RCY (rusticyanin), Cyc1, and Cox aa3 proteins to O2. Cyc1 protein consists of two chains, A and B. In the present study, a novel mutation (E121D) in the A chain of Cyc1 protein was selected due to electron receiving from Histidine 143 of RCY. Then, the changes performed in the E121D mutant were evaluated by MD simulations analyzes. Cyc1 and RCY proteins were docked by a Patchdock server. By E121D mutation, the connection between Zn 1388 of chain B and aspartate 121 of chain A weaken. Asp 121 gets farther from Zn 1388. Therefore, the aspartate gets closer to Cu 1156 of the RCY leading to the higher stability of the RCY/ Cyc1 complex. Further, an acidic residue (Glu121) becomes a more acidic residue (Asp121) and improves the electron transfer to Cyc1 protein. The results of RMSF analysis showed further ligand flexibility in mutation. This leads to fluctuation of the active site and increases redox potential at the mutation point and the speed of electron transfer. This study also predicts that in all respiratory chain proteins, electrons probably enter the first active site via glutamate and exit histidine in the second active site of each respiratory chain protein.