Dimensionless Variation of Seepage in Porous Media with Cracks Stimulated by Low-Frequency Vibration

Pulse excitation or vibration stimulation was imposed on the low permeable formation with cracks to enhance the production or injection capacity.During that process,a coupling of wave-induced flow and initial flow in dual-porous media was involved.Researchers had done much work on the rule of wave propagation in fractured porous media,whereas attentions on the variation law of flow in developing low permeable formation with cracks under vibration stimulation were not paid.In this study,the effect of low-frequency vibration on the seepage in dual-porous media was examined for the application of wave stimulation technology in developing reservoirs with natural cracks.A model for seepage of single-phase liquid in porous media with cracks under low-frequency vibration excitation was built by combining wave propagating theory for porous media with cracks and dual-porous media seepage mechanics.A governing equation group for the model,which was expressed by dimensionless fluid and solid displacements,was derived and solved with a numerical method.Variable physical properties were simulated to check the applicability of external low-frequency vibration load on dual-porous media and a parametric study for various vibration parameters.Stimulation of low-frequency vibration affected flow velocities of crack and rock matrix fluids.Compared with that in single-porous media,the stimulation effect on the fluid inner matrix of dual-porous media was relatively weakened.Different optimal vibration parameters were needed to increase the channeling flow between the crack and rock matrix or to only promote the flow velocity in the rock matrix.The theoretical study examines wave-coupled seepage field in fractured porous media with results that are applicable for low-frequency stimulation technology.

Repurposing of FDA-Approved drugs to predict new inhibitors against key regulatory genes in Mycobacterium tuberculosis

Tuberculosis(TB)disease has become one of the major public health concerns globally,especially in developing countries.Numerous research studies have already been carried out for TB,but we are still struggling for a complete and quick cure for it.The progress of Mycobacterium tuberculosis(MTB)strains resistant to existing drugs makes its cure and control very complicated.Therefore,it is the need of the hour to search for newer and effective drugs that can inhibit an increasing number of putative drug targets.We applied the drug repurposing concept to identify promising FDAapproved drugs against five key-regulatory genes(FurB,IdeR,KstR,MosR,and RegX3)of the MTB.The FDA drugs were virtually screened using a structure-based approach by GOLD versions 5.2,and subjected to rigid docking followed by an induced-fit docking algorithm to enhance the accuracy and prioritize drugs for repurposing.We found 11 candidate drugs(including ZINC03871613,ZINC03871614,ZINC03871615 as top scorer candidate drugs)that were frequently present within the top 20 GoldScore ranks and showed promising results.Furthermore,molecular dynamics simulation was performed to monitor the effect of the top scorer drugs on the structural stability of all the five targets,indicating that inhibitors preferentially bind to the active site of the targets.This work suggests that these known FDA-approved drugs open new application domains in the form of anti-tuberculosis agents.