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It is found that, in the studies of heavy ion transport with gyrokinetic simulations, the ion parallel drift frequency can reverse sign in velocity space when the amplitude variation of the electrostatic potential fluctuation is strong along the magnetic field line. As a result, the particle transport related to the parallel dynamics is strongly enhanced. It is noted that, while parallel gradient of the fluctuation amplitude can be instigated by a large magnetic shear or safety factor in a tokamak, the generic mechanism is independent of its cause, which suggests broader applications to kinetic plasma problems. Some relevant topics are briefly addressed in the end.
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http://dx.doi.org/10.1103/PhysRevLett.132.105101 | DOI Listing |
Front Pharmacol
August 2025
Stem Cell Research Center, Department of Pathology and Pathophysiology, School of Medicine, Tongji University, Shanghai, China.
Bladder cancer (BC) is a disease that predominantly affects older adults, with aging playing a critical role in its onset and progression. Age-associated phenomena, including immunosenescence and chronic inflammation, form a pro-tumor milieu, while genomic instability and epigenetic drift further increase cancer risk. The review highlights the dual role of DNA methylation in BC: global hypomethylation can activate transposable elements and oncogenes, whereas focal hypermethylation silences tumor-suppressor genes like CDKN2A, especially detrimental in older tissues that rely on these genes for senescence control.
View Article and Find Full Text PDFUnlabelled: Pheochromocytomas and paragangliomas (PPGLs) are rare chromaffin cell-derived neuroendocrine tumors of sympathetic (catecholamine-producing) or parasympathetic (nonsecretory) origin, frequently driven by dysregulation of hypoxia-inducible factor (HIF) signaling, particularly HIF-2α. Although often benign, PPGLs can metastasize unpredictably, with limited therapeutic options once disseminated. Progress has been hindered by the lack of robust preclinical models, especially those that capture their molecular complexity and microenvironmental influences.
View Article and Find Full Text PDFMicromachines (Basel)
August 2025
School of Integrated Circuits, Tsinghua University, Beijing 100084, China.
In this paper, a novel 4H-SiC LDMOS structure with a trench heterojunction in the source (referred as to THD-LDMOS) is proposed and investigated for the first time, to enhance the reverse recovery performance of its parasitic diode. Compared with 4H-SiC, silicon has a smaller band energy, which results in a lower built-in potential for the junction formed by P+ polysilicon and a 4N-SiC N-drift region. A trench P+ polysilicon is introduced in the source side, forming a heterojunction with the N-drift region, and this heterojunction is unipolar and connected in parallel with the body PiN diode.
View Article and Find Full Text PDFNat Commun
August 2025
Department of Psychiatry, Yale School of Medicine, New Haven, CT, USA.
The role of internally-generated network dynamics in rapid temporal sequence coding, updating, and parallel recalling of alternate spatial and mental navigation contexts has remained unclear. Here, we revealed rapid emergence of temporally-compressed hippocampal theta sequences in adult male rats within 1-2 laps of a novel detour via re-purposing of pre-existing correlated neuronal sequence motifs expressed during pre-detour sleep. Detour experience-induced neuronal remapping and plasticity were consolidated and reconfigured hippocampal network during post-detour sleep, which predicted future representational drift expressed during the following post-detour reversal-track runs.
View Article and Find Full Text PDFChemphyschem
August 2025
Physical and Computational Sciences Directorate, Pacific Northwest National Laboratory, Richland, Washington, 99352, US.
Electrical double layer (EDL) models are commonly adopted as a framework for understanding electrokinetic properties at mineral-fluid interfaces but the dynamics of ion and water mobilities are typically not well known. Extending the previous work performed at equilibrium conditions, here it is examined how applied electric fields induce mobilities of monovalent and divalent ions at hydroxylated quartz (001) and (101) interfaces with various electrolyte solutions (NaCl, KCl, and CaCl). The simulations reveal how the diffusion coefficients depend on the orientation and magnitude of the applied electric field, with a particularly strong effect for fields applied parallel to the quartz surfaces.
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