Graphene-Based Composite Right/Left-Handed Leaky-Wave Antenna at Terahertz

AbstractIn this paper, a simple terahertz (THz) leaky-wave antenna (LWA) composed of periodic gapped graphene ribbons and a silicon substrate is presented. The graphene sheets of the antenna operate in an electric field with a resonance distribution of transverse electric (TE) surface plasmon polaritons (SPPs). The THz LWA has both negative and positive propagation constant with the variation of frequencies. Thus, the LWA performs as a composite right/left-handed (CRLH) LWA with backfire-to-endfire beam steering capability in the THz band. The working principle of the THz LWA is analyzed in detail using the theory of dispersion relation formulae and the equivalent CRLH circuit model. The THz LWA is verified by numerical simulations, and the frequency scannable capability of the THz LWA is confirmed. The proposed antenna has great potential applications for the THz LWA of the radiation capability in the entire upper quadrants.
Source: Plasmonics - Category: Biomedical Science Source Type: research

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Conclusions: The results of this analysis show differences between PBS and PS/US with regards to two-fold MID changes in urinary function at 12 months, but no differences for average score declines over time. Future studies evaluating PRO measures between the two PBT modalities are warranted. PMID: 32258443 [PubMed - as supplied by publisher]
Source: Clinical Prostate Cancer - Category: Cancer & Oncology Authors: Tags: Clin Transl Radiat Oncol Source Type: research
Objectives The aim of this study was to evaluate the performance of an automated workflow for multiparametric magnetic resonance imaging (mpMRI) of the prostate compared with a manual mpMRI workflow. Materials and Methods This retrospective study was approved by the local ethics committee. Two MR technicians scanned 2 healthy volunteers with a prototypical highly automated workflow (Siemens Healthineers GmbH, Erlangen, Germany) and with a manually adjusted scan protocol each. Thirty patients (mean age ± standard deviation, 68 ± 11 years; range, 41–93 years) with suspected prostate cancer underwent ...
Source: Investigative Radiology - Category: Radiology Tags: Original Articles Source Type: research
Introduction Magnetic resonance imaging (MRI) of the abdomen increasingly incorporates diffusion-weighted imaging (DWI) sequences. Whereas DWI can substantially aid in detecting and characterizing suspicious findings, it remains unclear to what extent the use of ultra-high b-value DWI might further be of aid for the radiologist especially when using DWI sequences with advanced processing. The target of this study was therefore to compare high and ultra-high b-value DWI in abdominal MRI examinations. Methods This institutional review board–approved, prospective study included abdominal MRI examinations of 70 onco...
Source: Investigative Radiology - Category: Radiology Tags: Original Articles Source Type: research
Conclusions Spiral-TOFs may deliver high-quality intracranial vessel imaging thus matching the performance of conventional parallel imaging–accelerated TOFs (such as the SENSE). Specifically, imaging can be performed at unprecedented scan times as short as 1:32 minutes per sequence (70.12% scan time reduction compared with SENSE). Optionally, spiral imaging may also be used to increase spatial resolution while maintaining the scan time of a Cartesian-based acquisition schema. The CNR was decreased in spiral-TOF images.
Source: Investigative Radiology - Category: Radiology Tags: Original Articles Source Type: research
A scandal-hit hospital trust has been rated “inadequate” for the second time in a row, after inspectors found serious patient safety concerns at its two emergency departments.
Source: HSJ - Category: UK Health Source Type: news
Condition:   Post-transplant Lymphoproliferative Disorder Interventions:   Drug: Rituximab;   Drug: Acalabrutinib;   Diagnostic Test: CT scans Sponsor:   Deepa Jagadeesh Not yet recruiting
Source: - Category: Research Source Type: clinical trials
CONCLUSION: For the CBCT unit used in this study, the low-dose CBCT protocol for TMJ examination was diagnostically comparable to the manufacturer-recommended protocol, but delivered a five times lower radiation dose. There is an urgent need to evaluate protocols for CBCT examinations of TMJ in order to optimize them for a radiation dose as low as diagnostically acceptable (the ALADA principle recommended by NCRP). PMID: 32250642 [PubMed - as supplied by publisher]
Source: Dentomaxillofacial Radiology - Category: Radiology Tags: Dentomaxillofac Radiol Source Type: research
CONCLUSIONS: Telemedicine has provided Victorian regional hospitals access to expert care for emergency department patients with suspected acute stroke. Eligible patients with ischaemic stroke are now receiving stroke thrombolysis more quickly and safely. PMID: 32255520 [PubMed - as supplied by publisher]
Source: Medical Journal of Australia - Category: General Medicine Tags: Med J Aust Source Type: research
Authors: Cousiño JPC, Luna F, Torche M, Vigueras S, Torche E, Valdés G Abstract Background: The standard of care is to utilize intraoperative neurophysiological monitoring (IOM) of triggered electromyography (tEMG) during posterior lumbosacral instrumented-fusion surgery. IOM should theoretically signal misplacement of S1 screws into the neural L5-S1 foramen or spinal canal, utilizing screw stimulation, and recording of the lower limb muscles and the anal sphincter. Here, we evaluated when and whether anterolateral S1 screw malposition could be detected by IOM/tEMG during open posterior lumbosacral in...
Source: Surgical Neurology International - Category: Neurosurgery Tags: Surg Neurol Int Source Type: research
Conclusion: Integrating preoperative nTMS motor mapping in treatment planning allowed us to reduce dose distributions to perilesional motor fibers while achieving salvage of motor function, lasting seizure freedom, and tumor control. These initial data along with our review of the available literature suggest that nTMS can be of significant assistance in brain radiosurgery. Prospective studies including larger number of patients are still warranted. PMID: 32257555 [PubMed - as supplied by publisher]
Source: Surgical Neurology International - Category: Neurosurgery Tags: Surg Neurol Int Source Type: research
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