We describe new configurations of electromagnetic (EM) material parameters, the electric permittivity epsilon and magnetic permeability micro, which allow one to construct devices that function as invisible tunnels. These allow EM wave propagation between the regions at the two ends of a tunnel, but the tunnels themselves and the regions they enclose are not detectable to lateral EM observations. Such devices act as wormholes with respect to Maxwell's equations and effectively change the topology of space vis-à-vis EM wave propagation. We suggest several applications, including devices behaving as virtual magnetic monopoles, invisible cables, and scopes for MRI-assisted surgery.
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http://dx.doi.org/10.1103/PhysRevLett.99.183901 | DOI Listing |
Phys Med
January 2025
Department of Radiation Oncology, IRCCS Sacro Cuore Don Calabria Hospital, Via Don A. Sempreboni 5, 37024 Negrar di Valpolicella, VR, Italy; University of Brescia, Brescia, Italy.
Purpose: Adaptive MRgRT by 1.5 T MR-linac requires independent verification of the plan-of-the-day by the primary TPS (Monaco) (M). Here we validated a Monte Carlo-based dose-check including the magnetostatic field, SciMoCa (S).
View Article and Find Full Text PDFElife
January 2025
Department of Psychology, University of York, North Yorkshire, United Kingdom.
Processing pathways between sensory and default mode network (DMN) regions support recognition, navigation, and memory but their organisation is not well understood. We show that functional subdivisions of visual cortex and DMN sit at opposing ends of parallel streams of information processing that support visually mediated semantic and spatial cognition, providing convergent evidence from univariate and multivariate task responses, intrinsic functional and structural connectivity. Participants learned virtual environments consisting of buildings populated with objects, drawn from either a single semantic category or multiple categories.
View Article and Find Full Text PDFSICOT J
January 2025
Department of Orthopaedics, School of Medicine, Jichi Medical University, Shimotsuke, Japan.
Purpose: To clarify the location of the popliteal artery (PA) is relative to the tibial osteotomy plane in patients with medial and lateral unicompartmental knee osteoarthritis (KOA) undergoing UKA.
Methods: Preoperative MRI and postoperative radiographs obtained from 50 patients with unicompartmental KOA who underwent fixed-bearing UKA were analyzed. The amount of tibial resection was determined from the surgical records, and a line was drawn parallel to the tibial posterior tilt angle on the sagittal MR image to create a virtual tibial cut line.
BMJ Open
January 2025
Department of Rheumatology and Physiotherapy, Third Faculty of Medicine, Charles University and Thomayer University Hospital, Prague, Czech Republic
Introduction: Upper limb (UL) impairment is common in people with multiple sclerosis (pwMS), and functional recovery of the UL is a key rehabilitation goal. Technology-based approaches, like virtual reality (VR), are increasingly promising. While most VR environments are task-oriented, our clinical approach integrates neuroproprioceptive 'facilitation and inhibition' (NFI) principles.
View Article and Find Full Text PDFJ Orthop Surg Res
January 2025
Medical school, Kunming University of Science and Technology, Kunming, Yunnan, China.
Objective: In-depth investigation of the diagnostic performance of dual-energy CT (DECT) virtual non-calcium (VNCa) technique for sacroiliac joint bone marrow edema (BME) in patients with ankylosing spondylitis(AS).
Methods: A total of 42 patients with AS)who underwent sacroiliac joint MRI and DECT scans on the same day at our Rheumatology and Immunology Department between August 2022 and June 2023 were selected. Using MRI as the reference standard, the presence of BME on the iliac and sacral surfaces was evaluated, resulting in the categorization of patients into BME-positive and BME-negative groups.
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