Incidents and Complications of Permanent Venous Central Access Systems: A Series of 1,460 Cases

Massine El Hammoumi,Mohammed El Ouazni,Adil Arsalane,Fayçal El Oueriachi,Hamid Mansouri,El Hassane Kabiri 대한흉부외과학회 2014 Journal of Chest Surgery (J Chest Surg) Vol.47 No.2

Background: Implanted venous access devices or permanent central venous access systems (PCVASs) are routinely used in oncologic patients. Complications can occur during the implantation or use of such devices. We describe such complications of the PCVAS and their management. Methods: Our retrospective study included 1,460 cases in which PCVAS was implanted in the 11 years between January 2002 and January 2013, including 810 women and 650 men with an average age of 45.2 years. We used polyurethane or silicone catheters. The site of insertion and the surgical or percutaneous procedure were selected on the basis of clinical data and disease information. The subclavian and cephalic veins were our most common sites of insertion. Results: About 1,100 cases (75%) underwent surgery by training surgeons and 360 patients by expert surgeons. Perioperative incidents occurred in 33% and 12% of these patients, respectively. Incidents (28%) included technical difficulties (n=64), a subcutaneous hematoma (n=37), pneumothoraces (n=15), and an intrapleural catheter (n=1). Complications in the short and medium term were present in 14.2% of the cases. Distortion and rupture of the catheter (n=5) were noted in the costoclavicular area (pinch-off syndrome). There were 5 cases of catheter migration into the jugular vein (n=1), superior vena cava (n=1), and heart cavities (n=3). No patient died of PCVAS insertion or complication. Conclusion: PCVAS complications should be diagnosed early and treated with probable removal of this material for preventing any life-threatening outcome associated with complicated PVCAS.

Elastofibroma Dorsi: Clinicopathological Analysis of 76 Cases

Massine El Hammoumi,Abderrahim Qtaibi,Adil Arsalane,Fayçal El Oueriachi,El Hassane Kabiri 대한흉부외과학회 2014 Journal of Chest Surgery (J Chest Surg) Vol.47 No.2

Background: We aimed to investigate the epidemiological, clinical, paraclinical, and treatment aspects of elastofibroma dorsi through a retrospective study of 76 patients who underwent surgery between January 2008 and December 2012 in our department. Methods: Our study is retrospective between January 2008 and December 2012. We admitted 79 patients with a subscapular mass, and only 76 patients had ED. The others (n=2) had high associated risk of anesthesia and were managed by a medical treatment and one patient had a subscapular sclerotic hemangioma. Results: The average age of the patients was 49 years (range, 38 to 70 years), with a female predominance (54 females and 22 males). Subscapular location was constant. The right, left, and bilateral form was noted in 41, 15 and 20 cases, respectively. The diagnosis was clinical in 60 cases. Ultrasound and computerized tomography scans confirmed the diagnosis of an ill-defined mass in a subscapular location in all cases. Surgical treatment consisted of complete resection of the mass. The clinical diameter of the mass remained significantly lower than that of the surgical specimen (7 cm versus 12 cm) because the major hidden part of the mass in the subscapular area was inaccessible to palpation. Complications were noted in 9 cases (11.8%), seroma in 8 cases (10.5%), infection of wound site in 4 cases (5%), and parietal textilome in one case (1%). No case of recurrence was noted. Conclusion: Surgery of elastofibroma is unique because of the subscapular location of the parietal tumor, whose histological fibrous nature makes it very adherent to the chest wall.

Iran and the US

Arsalan Ghorbani Sheikhneshin 서울대학교 국제학연구소 2009 Journal of International and Area Studies Vol.16 No.1

Iran-US relations have been poor since the Islamic Revolution in 1979. All efforts to improve the relations have been frustrated. A rapprochement seems highly unlikely, especially, due to the Iranian nuclear program. Tehran has rejected such accusations and emphasized that their nuclear program is intended for civilian purposes. This paper examines the main claims and counter claims between Iran and the US, especially over terrorism-related issues. It argues that the US should revise its foreign policy, from aggressive and arrogant tactics to a policy of engagement and face-to-face negotiations. This paper emphasizes that the continuations of hard line policies, such as sanctions and war, against Iran would be counterproductive and will throw the whole region in turmoil.

Source rock potential of the Early Cretaceous intervals in the Darquain field, Abadan Plain, Zagros Basin, SW Iran

Arsalan Zeinalzadeh,Reza Moussavi-Harami,Asadollah Mahboubi,Vali Ahmad Sajjadian 한국지질과학협의회 2018 Geosciences Journal Vol.22 No.4

The Darquain field is located in the Abadan Plain SW Iran, which has a high potential for exploration and production of hydrocarbon resources with poorly defined petroleum systems. The goal of this paper is to characterize the Cretaceous source rock potential in the Darquain field. A gamma-sonic log was used as a proxy to identify probable source rock zones and to select sample depths. A total of 37 samples were analyzed by Rock-Eval, elemental, Gas Chromatography (GC) and gas chromatographymass spectrometry (GC-MS) techniques. The petroleum generation potential, as well as origin of the organic matter of samples, have been investigated. The results of this study indicate that, in the Early Cretaceous successions, there are favorable source zones in Garau, Gadvan, and Kazhdumi Formations. These source zones predominantly contain organic matter from marine origin, suggesting kerogen type II, while some samples contain terrestrial organic matters, suggesting kerogen type III. The Lower Garau zone, with 1.14 to 14.29% total organic carbon (TOC), is an excellent source rock with a fair genetic potential in the range of 2.74 and 9.5 mg/g. Elemental analysis results in the Lower Garau zone allow the classification of kerogens as high-sulfur. There are very good source zones in the Kazhdumi Formation, with fair to good genetic potential. The results of Rock-Eval and petrophysical analyses show that gamma ray data can be used as a useful tool to determine the potential source zones, although where TOC is less than 1% there is inconsistency. The results obtained from the biomarker characteristics are in agreement with the results of Rock-Eval pyrolysis and indicated carbonate source rocks, which contain a mixture of marine organic matter with a minor amount of terrigenous organic matter. Biomarker characteristics also suggest that the organic matter was deposited in a marine environment under reducing conditions, and that Early Cretaceous source zones are at the stage of early oil window to peak of oil generation.

A Simplified SVPWM for Three Level Inverters to Eliminate Leakage Currents in Transformeless Photovoltaic Systems

Arsalan Ansari(아르살란 안살리),Hee-Jun Kim(김희준) 대한전기학회 2016 전기학회논문지 Vol.65 No.2

This paper proposes a simplified SVPWM for three level inverters in transformerless photovoltaic (PV) systems. With the proposed SVPWM the three level space vector (SV) diagram is divided into only six sectors as in conventional two level SV diagram in such a way that only seven SVs are used among all the available SVs of three level inverter. The main features of the proposed SVPWM are that it is simple to implement, less switching losses as compared to conventional SVPWM and most importantly it eliminates the leakage currents in transformerless PV systems. Detailed theoretical analysis of the proposed SVPWM are presented and verified by numerical simulations and experimental results.

Analysis of a Novel DC-DC Converter with High Conversion Ratio

Arsalan Ansari,Hee-Jun Kim,Gyung-Seok Han 대한전기학회 2013 대한전기학회 학술대회 논문집 Vol.2013 No.10

Optimal stiffness distribution in preliminary design of tubed-system tall buildings

Arsalan Alavi,Reza Rahgozar 국제구조공학회 2018 Structural Engineering and Mechanics, An Int'l Jou Vol.65 No.6

This paper presents an optimal pattern for distributing stiffness along a framed tube structure through an analytic equation, which may be used during the preliminary design stage. Most studies in this field are computationally intensive and time consuming, while a hand-calculation method, as presented here, is a more suitable tool for sensitivity analyses and parametric studies. Approach in development of the analytic model is to minimize the mean compliance (external work) for a given volume of material. A variational statement of the problem is made, and a specified deformation-profile is obtained as the necessary condition for a minimum; enforcing this condition, stiffness is then computed. Due to some near-zero values for stiffness, the problem is modified by considering a lower bound constraint. To deal with this constraint, the design domain is assumed to be divided into two zones of constant stiffness and constant curvature; and the problem is restated in terms of these concepts. It will be shown that this methodology allows for easy computation of stiffness through an analytic and dimensionless equation, valid in any system of units. To show practicality of the proposed method, a tubed-system structure with uniform stiffness distribution is redesigned using the proposed model. Comparative analyses of the results reveal that in addition to simplicity of the proposed method, it provides a rather high degree of accuracy for real-world problems.

Effect of Trade Liberalization on Asymmetric Countries for Homogenous and Differentiate Product: Case of Pakistan-China Free Trade Agreement

Arsalan Ahmed,Qi Jian Hong,Hassan Tahir 인하대학교 정석물류통상연구원 2021 JOURNAL OF INTERNATIONAL LOGISTICS AND TRADE Vol.19 No.1

The study performs an empirical test to assess the impact of the Pakistan-China Free trade agreement (FTA) on Pakistan, China, and the World's exports under homogenous and differentiated products. This study employs the modeling with Poisson specification with Poisson Pseudo-Maximum Likelihood method for the estimations. The results of empirical test show that the effect of FTA on the FTA and Non-FTA countries is greater in the differentiated product as compared to the homogenous product. Therefore, one of the most important policy implications provided by this study is that export enterprises need to concentrate on differentiated products as compare to the homogenous products after the implementation of the Pakistan-China FTA. Moreover, the previous literature concluded that Pakistan-China FTA was more beneficial for China as compared to Pakistan. However, according to this study, if Pakistani enterprises focus more on differentiated products as compared to homogenous products, then it will be equally beneficial for both Chinese and Pakistani enterprises. This study will contribute to the literature by considering the Bertrand competition between asymmetric countries and find out the effect of the FTA on these three countries. It considers China, Pakistan, and the Rest of the World as first, second, and third countries.

Modeling of unreinforced brick walls under in-plane shear & compression loading

Arsalan Kalali,Mohammad Zaman Kabir 국제구조공학회 2010 Structural Engineering and Mechanics, An Int'l Jou Vol.36 No.3

The study of the seismic vulnerability of masonry buildings requires structural properties of walls such as stiffness, ultimate load capacity, etc. In this article, a method is suggested for modeling the masonry walls under in-plane loading. At the outset, a set of analytical equations was established for determining the elastic properties of an equivalent homogeneous material of masonry. The results for homogenized unreinforced brick walls through detailed modeling were compared in different manners such as solid and perforated walls, in-plane and out-of-plane loading, etc, and it was found that this method provides suitable accuracy in estimation of the wall linear properties. Furthermore, comparison of the results of proposed modeling with experimental out coming indicated that this model considers the non linear properties of the wall such as failure pattern, performance curve and ultimate strength, and would be appropriate to establish a parametric study on those prone factors. The proposed model is complicated; therefore, efforts need to be made in order to overcome the convergency problems which will be included in this study. The nonlinear model is basically semi-macro but through a series of actions, it can be simplified to a macro model.

A 3 kW Bidirectional DC-DC Converter for Electric Vehicles

Arsalan Ansari,Puyang Cheng,Hee-Jun Kim 대한전기학회 2016 Journal of Electrical Engineering & Technology Vol.11 No.4

A bidirectional DC-DC converter (BDC) is an indispensable electrical unit for the electric vehicles (EVs). High efficiency, high power density, isolation, light weight and reliability are all essential requirements for BDC. In this paper, a 3 kW BDC for the battery charger of EVs is proposed. The proposed converter consists of a half-bridge structure on the primary side and an isolation transformer and a synchronous rectifier structure on the secondary side. With this topology, minimum number of switching devices are required for bidirectional power flow between the two dc buses of EVs. The easy implementation of the synchronous rectification gives advantages in terms of efficiency, cost and flexibility. The proposed BDC achieves high efficiency when operating in both modes (step-up and step-down). A 3 kW prototype is implemented to verify theoretical analysis and the performance of the proposed converter.