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1. Probabilistic Voltage Sensitivity based Preemptive Voltage Monitoring in Unbalanced Distribution Networks

   https://doi.org/10.1109/NAPS50074.2021.9449792  

   Abujubbeh, Mohammad; Munikoti, Sai; Natarajan, Balasubramaniam (April 2021, 2020 52nd North American Power Symposium (NAPS))
2. Hydrophobic residues in S1 modulate enzymatic function and voltage sensing in voltage-sensing phosphatase

   https://doi.org/10.1085/jgp.202313467  

   Rayaprolu, Vamseedhar; Miettinen, Heini_M; Baker, William_D; Young, Victoria_C; Fisher, Matthew; Mueller, Gwendolyn; Rankin, William_O; Kelley, John_T; Ratzan, William_J; Leong, Lee_Min; et al (May 2024, Journal of General Physiology)

   The voltage-sensing domain (VSD) is a four-helix modular protein domain that converts electrical signals into conformational changes, leading to open pores and active enzymes. In most voltage-sensing proteins, the VSDs do not interact with one another, and the S1–S3 helices are considered mainly scaffolding, except in the voltage-sensing phosphatase (VSP) and the proton channel (Hv). To investigate its contribution to VSP function, we mutated four hydrophobic amino acids in S1 to alanine (F127, I131, I134, and L137), individually or in combination. Most of these mutations shifted the voltage dependence of activity to higher voltages; however, not all substrate reactions were the same. The kinetics of enzymatic activity were also altered, with some mutations significantly slowing down dephosphorylation. The voltage dependence of VSD motions was consistently shifted to lower voltages and indicated a second voltage-dependent motion. Additionally, none of the mutations broke the VSP dimer, indicating that the S1 impact could stem from intra- and/or intersubunit interactions. Lastly, when the same mutations were introduced into a genetically encoded voltage indicator, they dramatically altered the optical readings, making some of the kinetics faster and shifting the voltage dependence. These results indicate that the S1 helix in VSP plays a critical role in tuning the enzyme’s conformational response to membrane potential transients and influencing the function of the VSD. 

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3. Recent progress in bio-voltage memristors working with ultralow voltage of biological amplitude

   https://doi.org/10.1039/D2NR06773K  

   Fu, Tianda; Fu, Shuai; Yao, Jun (March 2023, Nanoscale)

   Neuromorphic systems built from memristors that emulate bioelectrical information processing in a brain may overcome limits in traditional computing architectures. However, functional emulation alone may still not attain all the merits of bio-computation, which uses action potentials of 50-120 mV at least 10-time lower than signal amplitude in conventional electronics to achieve extraordinary power efficiency and effective functional integration. Reducing the functional voltage in memristors to this biological amplitude thus can advance neuromorphic engineering and bio-emulated integration. This review aims to provide a timely update on the effort and progress in this burgeoning direction, covering aspects in device material composition, performance, working mechanism, and potential application. 

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4. Mobility and threshold voltage extraction in transistors with gate-voltage-dependent contact resistance

   https://doi.org/10.1038/s41699-024-00506-4  

   Bennett, Robert_K A; Hoang, Lauren; Cremers, Connor; Mannix, Andrew J; Pop, Eric (December 2025, npj 2D Materials and Applications)
5. Mitigating Voltage Drop in Resistive Memories by Dynamic RESET Voltage Regulation and Partition RESET

   https://doi.org/10.1109/HPCA47549.2020.00031  

   Zokaee, Farzaneh; Jiang, Lei (February 2020, IEEE International Symposium on High Performance Computer Architecture)

   The emerging resistive random access memory (ReRAM) technology has been deemed as one of the most promising alternatives to DRAM in main memories, due to its better scalability, zero cell leakage and short read latency. The cross-point (CP) array enables ReRAM to obtain the theoretical minimum 4F^2 cell size by placing a cell at the cross-point of a word-line and a bit-line. However, ReRAM CP arrays suffer from large sneak current resulting in significant voltage drop that greatly prolongs the array RESET latency. Although prior works reduce the voltage drop in CP arrays, they either substantially increase the array peripheral overhead or cannot work well with wear leveling schemes. In this paper, we propose two array micro-architecture level techniques, dynamic RESET voltage regulation (DRVR) and partition RESET (PR), to mitigate voltage drop on both bit-lines and word-lines in ReRAM CP arrays. DRVR dynamically provides higher RESET voltage to the cells far from the write driver and thus encountering larger voltage drop on a bit-line, so that all cells on a bit-line share approximately the same latency during RESETs. PR decides how many and which cells to reset online to partition the CP array into multiple equivalent circuits with smaller word-line resistance and voltage drop. Because DRVR and PR greatly reduce the array RESET latency, the ReRAM-based main memory lifetime under the worst case non-stop write traffic significantly decreases. To increase the CP array endurance, we further upgrade DRVR by providing lower RESET voltage to the cells suffering from less voltage drop on a word-line. Our experimental results show that, compared to the combination of prior voltage drop reduction techniques, our DRVR and PR improve the system performance by 11.7% and decrease the energy consumption by 46% averagely, while still maintaining >10-year main memory system lifetime. 

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