The use of L1 in language classroom has been traditionally repressed by applied linguists. However, in recent years, it is believed that switching to L1 can be considered a pedagogical instrument by teachers rather than a heterodox. Consequently, this two-phase study was an attempt to investigate the functions that are fulfilled by EFL teachers through their use of L1. In the first phase (i.e., theoretical phase), a thorough analysis of the available literature on teacher CODE switching was conducted with the aim of developing a typology which would encompass various functions of teachers’ L1 use. In the second phase (i.e., empirical phase), in order to test the construct validity of the typology, data was collected from four EFL teachers by video recording an entire session of their teaching. The instances of CODE switching in their performance were transcribed and CODEd in the light of the typology. The results of data analysis indicated that the typology has external manifestations in teachers’ instances of CODE switching. It was also discovered that, among the selected participants, L1 was mostly used to fulfill pedagogical functions rather than social ones. Implications of the findings are discussed and suggestions for further research are provided.

Background and Objective: Simulation using Monte Carlo technique is a practical method for assessment of the characteristics of the clinical photon beam from the treatment head. The accuracy of the simulation results is based on the VALIDATION of the Monte Carlo models used in the calculation. This study validated the simulation with BEAMnrc CODE for 6MV energy.Subjects and Methods: The accelerators of Varian Clinic 2100C/D for photon beam 6MV were simulated using the BEAMnrc CODE system. A cylindrical mono energetic with 5.7, 5.9, 6 MV energies and 1, 2, 3 mm radius were applied. Two phase space files were scored below the exit window and above the phantom then analyzed the beam characteristics using BEAMdp and calculated the percentage depth dose and profile at 10cm using DOSXYZ CODE. In this work, measurements were performed using 0.13 cc ion chamber inside a water phantom with dimension 50×50×50cm3. At the end of simulation, the results of the measured data were compared using gamma index with criteria 2%/2mm.Result: By increasing the electron energy, percentage depth dose in buildup region was reduced and became closer to measurements. With increasing the diameter of the electron source, the photons were diverged and the edges of the profiles showed a sharp drop compared to the dose measurements.Conclusion: Finally good agreement (gamma index within2%/2mm) between the measurements and simulations was achieved for field sizes of 4×4 ،10×10 and 30×30cm2 with radial of incident electrons 0.2cm at source surface distances of 100cm.

One of the measures taken to protect witnesses in the Statute of the International Criminal Court and the CODE of Judicial Procedure of our country is to keep their identities secret. Both the defendant is important and the defendant's right can not be ignored for the sake of witness testimony or the defendant's defense rights were endangered and threatened without regard to witness safety. Regarding the validity and positive value of the testimony of anonymous witnesses, this question arises To what extent are their value, credibility and testimony valued? The CODE of Criminal Procedure is silent on the validity and value of the testimony of anonymous witnesses and whether such testimony can alone be used to document a conviction. It seems that the value and validity of the testimony of anonymous witnesses, if it is not possible for the accused to face and challenge the witnesses, is not equal to the identity of the witnesses in this article. And the security of intuitions has been examined.

Background: The expansion of the use of audio and video media technology has faced society with many medical, cultural and economic challenges. In the meantime, excessive use of mobile phones can cause many problems. Objective: The aim of this study was to construct and validate a questionnaire on physical and psychological injuries of mobile phones. Method: The method of the present study was descriptive-correlational and confirmatory factor analysis. The statistical population of the study consisted of all citizens of Khorramabad with a diploma or higher in 1399, which was selected as a statistical sample by available sampling method of 200 people online and virtual. Results: The results showed that the factorized physical and psychological harm questionnaire of cell phone with 42 questions and 10 components (fear of loss, vibration syndrome, duck syndrome, nomophobia, insomnia, hearing problem, eye syndrome, tunnel and neck syndrome SMS) and has good reliability, validity and flexibility in terms of psychometrics. Discussion and Conclusion: The questionnaire of factor analysis of physical and psychological injuries of mobile phones can be used to identify and study the physical and psychological injuries of mobile phones.