Atrial fibrillation (AF) is related to mutations at the genetic level. This includes mutations in genes that encode KCNQ1, a subunit of the I Ks channel. Here, we investigate the mechanism of gain-of-function in I Ks towards the occurrence of AF. We used the Courtemanche-Ramirez-Nattel (CRN) human atrial cell model (Am J Physiol Heart Circ Physiol 275:H301-H321, 1998) and applied the modification proposed by Hasegawa et al. (Heart Rhythm 11:67-75, 2014) to fit the behavior of I Ks due to the G229D mutation in KCNQ1 under a heterozygous mutant form. This was incorporated into two-(2D) and three-dimensional (3D) tissue models, where the mutation sustained a reentrant wave. However, under the wild-type condition, the reentrant wave terminated before the end of our simulations (in 2D, the spiral wave terminated before 10 s, while in 3D, the spiral wave terminated before 13 s). Sustained reentry under the mutation conditions also resulted in a spiral wave breakup in the 3D model, which was sustained until the end of the simulation (20 s), indicating AF.

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In the learning process, students still have misconceptions although the concept has been taught by the teacher. One of the causes of misconceptions comes from the students themselves. The teacher often does not know that students have misconceptions because the assessment that has been given does not review the cause of misconception that occurs in students. Students have misconception especially in Abstract concept like in chapter Kinetic Theory of Gases. Because of that, this study made three tier diagnostic instrument test to diagnose student’s misconception in chapter Kinetic Theory of Gases. Moreover, it is also done an analysis in order to know the quality of instrument that has been made. According to the trials, the percentage of average internal validity is about 84.6% which means it is in proper to use and the reliability of instrument is 0.752, meaning reliable to use. This instrument used to diagnose the students’ misconceptions on chapter Kinetic Theory of Gases.