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1. Non-innocent Intercalation of Diamines into Tetragonal FeS Superconductor

   https://doi.org/10.1021/acsaem.0c02996  

   Harmer, Colin P. ; Pak, Chongin ; Greenfield, Joshua T. ; Adeyemi, Adedoyin N. ; Gamage, Eranga H. ; Kovnir, Kirill ( January 2021 , ACS Applied Energy Materials)

   null (Ed.)
2. Strong anisotropy in nearly ideal tetrahedral superconducting FeS single crystals

   https://doi.org/10.1103/PhysRevB.93.094522  

   Borg, Christopher K. ; Zhou, Xiuquan ; Eckberg, Christopher ; Campbell, Daniel J. ; Saha, Shanta R. ; Paglione, Johnpierre ; Rodriguez, Efrain E. ( March 2016 , Physical Review B)
3. Cadence Tracking for Switched FES Cycling with Unknown Input Delay

   Allen, B. ; Cousin, C. ; Rouse, C. ; Dixon, W. ( January 2019 , 2019 IEEE 58th Conference on Decision and Control (CDC))

   Functional electrical stimulation (FES) induced cycling provides a means of therapeutic exercise and functional restoration for people affected by neuromuscular disorders. A challenge in closed-loop FES control of coordinated motion is the presence of a potentially destabilizing input delay between the application of the electrical stimulation and the resulting muscle contraction. Moreover, switching amongst multiple actuators (e.g., between FES control of various muscle groups and a controlled electric motor) presents additional challenges for overall system stability. In this paper, a closed-loop controller is developed to yield exponential cadence tracking, despite an unknown input delay, switching between FES and motor only control, uncertain nonlinear dynamics, and additive disturbances. Lyapunov-Krasovskii functionals are used in a Lyapunov-based stability analysis to ensure exponential convergence for all time. 

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4. Suppression of electronic correlations by chemical pressure from FeSe to FeS

   https://doi.org/10.1103/PhysRevB.96.121103  

   Reiss, P. ; Watson, M. D. ; Kim, T. K. ; Haghighirad, A. A. ; Woodruff, D. N. ; Bruma, M. ; Clarke, S. J. ; Coldea, A. I. ( September 2017 , Physical Review B)
5. FES Cycling and Closed-Loop Feedback Control for Rehabilitative Human–Robot Interaction

   https://doi.org/10.3390/robotics10020061  

   Cousin, Christian ; Duenas, Victor ; Dixon, Warren ( June 2021 , Robotics)

   null (Ed.)

   For individuals with movement impairments due to neurological injuries, rehabilitative therapies such as functional electrical stimulation (FES) and rehabilitation robots hold vast potential to improve their mobility and activities of daily living. Combining FES with rehabilitation robots results in intimately coordinated human–robot interaction. An example of such interaction is FES cycling, where motorized assistance can provide high-intensity and repetitive practice of coordinated limb motion, resulting in physiological and functional benefits. In this paper, the development of multiple FES cycling testbeds and safeguards is described, along with the switched nonlinear dynamics of the cycle–rider system. Closed-loop FES cycling control designs are described for cadence and torque tracking. For each tracking objective, the authors’ past work on robust and adaptive controllers used to compute muscle stimulation and motor current inputs is presented and discussed. Experimental results involving both able-bodied individuals and participants with neurological injuries are provided for each combination of controller and tracking objective. Trade-offs for the control algorithms are discussed based on the requirements for implementation, desired rehabilitation outcomes and resulting rider performance. Lastly, future works and the applicability of the developed methods to additional technologies including teleoperated robotics are outlined. 

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