Estimating intracranial parameters using an inverse mathematical model with viscoelastic elements that closely predicts complex ICP morphologies.

The quantitative relationship between arterial blood pressure (ABP) and intracranial pressure (ICP) waveforms has not been adequately explained. We hypothesized that the ICP waveform results from interferences between propagating and reflected pressure waves occurring in the cranium following the initiating arterial waveform. To demonstrate cranial effects on interferences between waves and generation of an ICP waveform morphology, we modified our previously reported mathematical model to include viscoelastic elements that affect propagation velocity.

When giants talk; robotic dialog during thoracolumbar and sacral surgery.

Background: Spinal trauma patients treated in a specialized hybrid operating room (OR) using two robotic systems communicating during surgery.

Methods: Retrospective review of patients with thoracolumbar or sacral fractures who underwent surgical fixation between Jan 2017 to Jan 2020 with robotic-guided percutaneous pedicle screw insertion in the specialized hybrid OR with Robotic flat panel 3D C-arm (ArtisZeego) for intraoperative interventional imaging connected with the robotic-guidance platform Renaissance (Mazor Robotics).

Results: Twenty eight surgeries were performed in 27 patients; 23 with traumatic spinal fractures, 4 with multi-level thoracolumbar compression fractures due to severe osteoporosis.

Initial definitive treatment of open femoral shaft fractures with retrograde nailing - is it safe? A retrospective analysis comparing antegrade to retrograde nailing.

Introduction: Treatment of severe open femoral fractures with retrograde intramedullary nailing, raises concerns of septic arthritis of the knee due to its intra-articular entrance point. There is little evidence concerning the safety of retrograde femoral nailing (RFN) usage in these cases, and what evidence there is does not necessarily include severe open fractures. Furthermore, the outcome of ballistic injuries treated in this manner and a comparison with antegrade femoral nailing (AFN), is yet to be established.

Recent use of formaldehyde-'free' hair straightening product and severe acute kidney injury.

Formaldehyde is present in hair straightening products even when labeled as formaldehyde-free. Inhaled absorption of formaldehyde causes renal tubular cytotoxicity. We report a teenager who developed severe acute kidney injury requiring renal replacement therapy shortly after exposure to a formaldehyde-'free' hair straightening product.

Generic Rotating-Frame-Based Approach to Chaos Generation in Nonlinear Micro- and Nanoelectromechanical System Resonators.

This Letter provides a low-power method for chaos generation that is generally applicable to nonlinear micro- and nanoelectromechanical systems (MNEMS) resonators. The approach taken is independent of the material, scale, design, and actuation of the device in question; it simply assumes a good quality factor and a Duffing type nonlinearity, features that are commonplace to MNEMS resonators. The approach models the rotating-frame dynamics to analytically constrain the parameter space required for chaos generation.