Light-induced switch based on edge modes in irradiated thin topological insulators

We investigate transport properties through nano-ribbons of thin topological insulators irradiated by high frequency light with circular polarization. By using high frequency regime, a coherent and quantized transport through the nano-ribbon is guaranteed and then Lanadauer formalism is applicable. It is demonstrated that the pseudo-spin edge modes inside the band gap can host transmission through this nano-junction which their localization on the top and bottom edges depend strongly on the light polarization. These edge modes persist even if we apply a source-drain bias. Based on this edge selectivity for the current, one can design a light-induced switch with an appropriate on/off ratio of the current which is composed of two scattering regions with opposite light polarization. The local current on each bond shows how the current is passing through the edges and jumps into the opposite edge. Furthermore, some other nano-junctions are proposed as electronic switches which are designed based on the mass term engineering of the scattering region by means of perpendicular magnetization induced by magnetic doping and also structure inversion asymmetry applied on the scattering region.Comment: 10 pages, 6 figure

Search-based Software Testing Driven by Automatically Generated and Manually Defined Fitness Functions

Search-based software testing (SBST) typically relies on fitness functions to guide the search exploration toward software failures. There are two main techniques to define fitness functions: (a) automated fitness function computation from the specification of the system requirements and (b) manual fitness function design. Both techniques have advantages. The former uses information from the system requirements to guide the search toward portions of the input domain that are more likely to contain failures. The latter uses the engineers' domain knowledge. We propose ATheNA, a novel SBST framework that combines fitness functions that are automatically generated from requirements specifications and manually defined by engineers. We design and implement ATheNA-S, an instance of ATheNA that targets Simulink models. We evaluate ATheNA-S by considering a large set of models and requirements from different domains. We compare our solution with an SBST baseline tool that supports automatically generated fitness functions, and another one that supports manually defined fitness functions. Our results show that ATheNA-S generates more failure-revealing test cases than the baseline tools and that the difference between the performance of ATheNA-S and the baseline tools is not statistically significant. We also assess whether ATheNA-S could generate failure-revealing test cases when applied to a large case study from the automotive domain. Our results show that ATheNA-S successfully revealed a requirement violation in our case study

Biliary Tract Disease in Pediatric Surgery Department: 10 Years Experience in Khouzestan-IRAN

Introduction: Our aim was to evaluate clinical manifestation, and outcome of biliary tract disease in patients referred for treatment to two referral centers of pediatric surgery of Ahvaz.Materials and Methods: In this retrospective study, patients with biliary tract disease admitted in Imam Khomeini and Abuzar hospitals (two referral centers for pediatric surgery in Ahvaz) during a 10-year period starting from March 2000 were evaluated. Age, sex, clinical manifestation, type of surgery, imaging finding, laboratory finding, duration of hospital stay, blood product infusion, and mortality rates were recorded. Data was analyzed with SPSS Ver 13.0(Chicago, IL, USA). We used Chi-square and t-test for comparison.Results: Twenty cases (m=13, f=7) of biliary atresia were included in this study. Mean age at the time of diagnosis and operation was 82.11 days (30 days- 6.5 months). Jaundice (100%), acholic stool (55%), and dark brown urine (55%) were the most frequent clinical manifestation in patients with biliary atresia. Of all cases, 17 patients underwent surgery. Eighteen cases (m=11, f=7) of cholecystitis were included in this study. Abdominal pain (72%) was the most frequent sign. Eleven cases underwent surgery. Five cases of choledochal cyst (m=0, f=5) were included in this study. Abdominal pain and vomiting was the most common clinical manifestation in cases with choledocal cyst.Conclusion: Jaundice, acholic stool, and dark brown urine were the most frequent clinical manifestation in cases with biliary atresia. Mean age at the time of diagnosis and operation for biliary atresia was 82.11 days (30 days- 6.5 months). Abdominal pain was the most frequent sign of cholecystitis. Early referral and more experience are needed in order to increase survival of biliary atresia cases in our hospital

Recurrence and complications of pediatric inguinal hernia repair over 5 years

Introduction and aim Inguinal hernia is one of the most common pediatric diseases in children and it presents most commonly during the first year of life. The aim of this study was to determine epidemiologic indexes and complications of inguinal hernia repair in pediatric patients who underwent inguinal hernia surgery.Patients and methods This retrospective study was carried out in the Imam Khomeini and the Abuzar hospitals. All inpatients who underwent surgery for inguinal hernia from 2003 to 2004 were included in this study. Their hospital records were reviewed till 2007 for age, sex, wound infection, recurrence, and other complications. The v2-test was used for analysis using SPSS, version 13.0.Results In this study, 269 children were included. Of all the patients, 237 (88.1%) were boys and 32 (11.9%) were girls (P < 0.001). The median age at the first reference to the surgeon was 2.93 years. Right-side and left-side inguinal hernia was observed in 136 (50.55%) and 92 (34.20%) cases, respectively. Bilateral inguinal hernia was observed in 41 (15.25%) cases. The frequency of recurrence was 2.2%, and was observed only in boys. Postoperative complications were observed in 5.2% of the cases. The most common of them was anesthetic complication.Conclusion Most of the cases involved male patients. All of the recurrences were in male patients. Postoperative complications were observed in 5.2% of the cases. Keywords: complication, inguinal hernia, pediatric, recurrenc

SAFER-HRC: Safety analysis through formal vERification in human-robot collaboration

Whereas in classic robotic applications there is a clear segregation between robots and operators, novel robotic and cyber-physical systems have evolved in size and functionality to include the collaboration with human operators within common workspaces. This new application field, often referred to as Human-Robot Collaboration (HRC), raises new challenges to guarantee system safety, due to the presence of operators. We present an innovative methodology, called SAFER-HRC, centered around our logic language TRIO and the companion bounded satisfiability checker Zot, to assess the safety risks in an HRC application. The methodology starts from a generic modular model and customizes it for the target system; it then analyses hazards according to known standards, to study the safety of the collaborative environment

Compare the effectiveness of two inguinal hernia repair techniques, Kugel and Lichtenstein repair

زمینه و هدف: هدف از انجام این مطالعه مقایسه نتایج دو روش ترمیم لیختن اشتاین و کوگل در بیماران مبتلا به فتق مغبنی می باشد. روش بررسی: در این مطالعه نیمه تجربی 42 بیمار مبتلا به فتق مغبنی با میانگین سنی 11 ± 9/49 سال وارد مطالعه و به طور تصادفی به دو گروه ترمیم کوگل و لیختن اشتاین تقسیم شدند. بیماران در طی عمل جراحی از نظر طول برش جراحی، مدت زمان عمل، بروزهماتوم، سروما، عفونت، احتباس ادراری و اختلالات حسی ناحیه اینگوئینال بوسیله آزمون t مستقل و آزمون دقیق فیشر مورد مقایسه قرار گرفتند. یافته ها: نتایج نشان داد که طول برش و زمان عمل جراحی در روش کوگل به طور معنی داری کمتر از لیختن اشتاین بود 001/0 >pسایر متغیرها تفاوت آماری معنی داری نداشتند 05/0 <