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Abstract Ram pressure stripping (RPS) is an important process that plays a significant role in shaping the evolution of cluster galaxies and their surrounding environment. Despite its recognized significance, the potential connection between RPS and active galactic nuclei (AGN) activity in cluster galaxies remains poorly understood. Recent claims, based on optical emission-line diagnostics, have suggested such a connection. Here, we investigate this relationship from an X-ray perspective, using a sample of galaxies undergoing RPS in four nearby galaxy clusters: A1656, A1367, A426, and A3627. This study is the first to test such a connection from an X-ray standpoint. Our analysis reveals no signs of enhanced X-ray AGN activity in our sample, with most RPS galaxies (~90%) showing X-ray luminosities below 10⁴¹erg s⁻¹in their central point sources. Moreover, there is no noticeable difference in X-ray AGN activity among RPS galaxies compared to a control sample of non-RPS galaxies, as demonstrated by the similar X-ray luminosities observed in their central point sources. While the most luminous X-ray AGN in our sample is found in ESO 137-002, a galaxy undergoing RPS in A3627, there is no evidence for a widespread enhancement of X-ray AGN activity due to RPS. Given the limited sample size of our study, this could also indicate that either the X-ray AGN enhancement from RPS is at most weak or the timescale for the X-ray AGN enhancement is short. This emphasizes the need for further investigations with larger X-ray samples to better understand the impact of RPS on AGN activity in cluster galaxies. 

We consider numerical approximations for a phase-field dendritic crystal growth model, which is a highly nonlinear system that couples the anisotropic Allen–Cahn type equation and the heat equation. By combining the stabilized-Invariant Energy Quadratization method with a novel decoupling technique, the scheme requires solving only a sequence of linear elliptic equations at each time step, making it the first, to the best of the author’s knowledge, totally decoupled, linear, unconditionally energy stable scheme for the model. We further prove the unconditional energy stability rigorously and present various numerical simulations to demonstrate the stability and accuracy. 

GABAergic interneuron dysfunction has been implicated in temporal lobe epilepsy (TLE), autism, and schizophrenia. Inhibitory interneuron progenitors transplanted into the hippocampus of rodents with TLE provide varying degrees of seizure suppression. We investigated whether human embryonic stem cell (hESC)-derived interneuron progenitors (hESNPs) could differentiate, correct hippocampal-dependent spatial memory deficits, and suppress seizures in a pilocarpine-induced TLE mouse model. We found that transplanted ventralized hESNPs differentiated into mature GABAergic interneurons and became electrophysiologically active with mature firing patterns. Some mice developed hESNP-derived tumor-like NSC clusters. Mice with transplants showed significant improvement in the Morris water maze test, but transplants did not suppress seizures. The limited effects of the human GABAergic interneuron progenitor grafts may be due to cell type heterogeneity within the transplants.