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The youngest species of Amphoracrinus, A. tenax new species, is described from the Muldraugh Member of the Borden Formation (early Viséan) of north-central Kentucky. With this new occurrence, both the oldest and youngest named species of Amphoracrinus are from North America. Numerous Tournaisian and Viséan crinoid faunas are documented in the United States, but only four are known to contain Amphoracrinus. Morphological analysis indicates that A. tenax is more closely aligned with species from China than with species from Western Europe or other species from North America, where Amphoracrinus was most diverse and abundant, which has implications for understanding paleogeographic dispersal. The holotype of A. tenax was partially disarticulated on the seafloor before burial, and final burial occurred early during disarticulation. The relative state of disarticulation from pinnules to columnals suggests that plates bound only with ligaments disarticulated as a function of surface area of ligaments binding an articulation. [ABSTRACT FROM AUTHOR]

Objectives: This study aimed to indicate the feasibility of a prototype electrical neuromodulation system using a closed-loop energy-efficient ultrasound-based mechanism for communication, data transmission, and recharging., Materials and Methods: Closed-loop deep brain stimulation (DBS) prototypes were designed and fabricated with ultrasonic wideband (UsWB) communication technology and miniaturized custom electronics. Two devices were implanted short term in anesthetized Göttingen minipigs (N = 2). Targeting was performed using preoperative magnetic resonance imaging, and locations were confirmed postoperatively by computerized tomography. DBS systems were tested over a wide range of stimulation settings to mimic minimal, typical, and/or aggressive clinical settings, and evaluated for their ability to transmit data through scalp tissue and to recharge the DBS system using UsWB., Results: Stimulation, communication, reprogramming, and recharging protocols were successfully achieved in both subjects for amplitude (1V-6V), frequency (50-250 Hz), and pulse width (60-200 μs) settings and maintained for ≥six hours. The precision of pulse settings was verified with <5% error. Communication rates of 64 kbit/s with an error rate of 0.05% were shown, with no meaningful throughput degradation observed. Time to recharge to 80% capacity was <9 minutes. Two DBS systems also were implanted in the second test animal, and independent bilateral stimulation was successfully shown., Conclusions: The system performed at clinically relevant implant depths and settings. Independent bilateral stimulation for the duration of the study with a 4F energy storage and full rapid recharge were achieved. Continuous function extrapolates to six days of continuous stimulation in future design iterations implementing application specific integrated circuit level efficiency and 15F storage capacitance. UsWB increases energy efficiency, reducing storage requirements and thereby enabling device miniaturization. The device can enable intelligent closed-loop stimulation, remote system monitoring, and optimization and can serve as a power/data gateway to interconnect the intrabody network with the Internet of Medical Things., Competing Interests: Conflict of Interest Emrecan Demirors, Tommaso Melodia, and Jorge Jimenez are cofounders of Bionet Sonar Inc and hold equity interest. Raffaele Guida and Ryan Burke were employees of the company at the time of the study. Bionet Sonar holds all rights for the technology and its personnel, and its founders led the design, development, fabrication, and feasibility testing of prototype devices, including data collection and analysis, decision to publish, and preparation of this manuscript. Joseph S. Neimat serves as a consultant for Medtronic and on a scientific advisory board for Abbott. Steven C. Koenig reports one conflict of interest (spouse is paid by Bionet Sonar for her assistance with grants administration activities but did not participate in any research and development activities and/or participation in the preparation of the manuscript)., (Copyright © 2024 International Neuromodulation Society. Published by Elsevier Inc. All rights reserved.)