fix paper.md

Author: yzeng

JOSS_paper/paper.md

@@ -95,7 +95,7 @@ IAMReX is built upon the foundations established in three of our previous public
 IAMReX is suitable for modeling multiphase flow problems and fluid-structure interaction problems. Its Level Set-based interface capturing technique can be beneficial for researchers studying phenomena such as wind over waves, breaking waves, and simulating the formation and disappearance of bubbles and droplets. Additionally, the immersed boundary method along with the collision models can parallelly resolve large-scale particles and capture their motions. Researchers working on studies of biological particle aggregation, sandstorms, wind erosion of ground surfaces, and seawater erosion of riverbeds are also among the target audience for this software.
 
 # State of the field
-We made great efforts to simulate more complex multiphase flows at higher resolution using IAMReX. One effort is to combine the AMR technique with the multidirect forcing immersed boundary method to resolve particles only on the finest-level grid. It significantly reduces the grid requirements for particle-resolved simulation compared with commonly used uniform grid solvers [Incompact3d](https://github.com/xcompact3d/Incompact3d), [CaNS](https://github.com/CaNS-World/CaNS), and [CP3d](https://github.com/GongZheng-Justin/CP3d). Additionally, we utilized a subcycling technique to alleviate the time step constraint on coarser levels. It minimizes the total time step needed by time advancement compared with the non-subcycling technique used in other AMR-related packages, such as [IBAMR](https://github.com/IBAMR/IBAMR.git), [basilisk](http://basilisk.fr/), and [incflo](https://github.com/AMReX-Fluids/incflo.git).
+We made great efforts to simulate more complex multiphase flows at higher resolution using IAMReX. One effort is to combine the AMR technique with the multidirect forcing immersed boundary method to resolve particles only on the finest-level grid. It significantly reduces the grid requirements for particle-resolved simulations compared with commonly used uniform grid solvers [Incompact3d](https://github.com/xcompact3d/Incompact3d), [CaNS](https://github.com/CaNS-World/CaNS), and [CP3d](https://github.com/GongZheng-Justin/CP3d). Additionally, we utilized a subcycling technique to alleviate the time step constraint on coarser levels. It minimizes the total time step needed by time advancement compared with the non-subcycling technique used in other AMR-related packages, such as [IBAMR](https://github.com/IBAMR/IBAMR.git), [basilisk](http://basilisk.fr/), and [incflo](https://github.com/AMReX-Fluids/incflo.git).
 
 # Acknowledgements