113 research outputs found
Dynamic Experiment Design Regularization Approach to Adaptive Imaging with Array Radar/SAR Sensor Systems
We consider a problem of high-resolution array radar/SAR imaging formalized in terms of a nonlinear ill-posed inverse problem of nonparametric estimation of the power spatial spectrum pattern (SSP) of the random wavefield scattered from a remotely sensed scene observed through a kernel signal formation operator and contaminated with random Gaussian noise. First, the Sobolev-type solution space is constructed to specify the class of consistent kernel SSP estimators with the reproducing kernel structures adapted to the metrics in such the solution space. Next, the âmodel-freeâ variational analysis (VA)-based image enhancement approach and the âmodel-basedâ descriptive experiment design (DEED) regularization paradigm are unified into a new dynamic experiment design (DYED) regularization framework. Application of the proposed DYED framework to the adaptive array radar/SAR imaging problem leads to a class of two-level (DEED-VA) regularized SSP reconstruction techniques that aggregate the kernel adaptive anisotropic windowing with the projections onto convex sets to enforce the consistency and robustness of the overall iterative SSP estimators. We also show how the proposed DYED regularization method may be considered as a generalization of the MVDR, APES and other high-resolution nonparametric adaptive radar sensing techniques. A family of the DYED-related algorithms is constructed and their effectiveness is finally illustrated via numerical simulations
The role of antibiotics in endoscopic sinus surgery
Purpose of reviewTo review and discuss recent literature regarding the use of antibiotics in relation to endoscopic sinus surgery (ESS), including perioperative antibiotics, postoperative antibiotics, and antibiotic usage in the setting of postoperative packing.Recent findingsPerioperative antibiotics are not recommended by the American Society of Health-System Pharmacists. The necessity of antibiotics following ESS is a heavily debated topic. Most studies show little to no improvement in outcomes. Significant improvement in quality-of-life outcomes and endoscopic scoring appears limited to the early postoperative period using conventional postoperative antibiotics. Prolonged macrolide therapy may improve long-term outcomes. There is no convincing evidence to show the need for antibiotics in the setting of postoperative packing.SummaryThe available evidence regarding antibiotic use in relation to ESS overall fails to demonstrate routine benefit; however, the studies have various limitations. Overall, future, well designed, large-scale prospective studies would be beneficial to direct appropriate antibiotic use, whether systemic or topical, in relation to ESS
International Consensus Statement on Rhinology and Allergy: Rhinosinusitis
Background: The 5 years since the publication of the first International Consensus Statement on Allergy and Rhinology: Rhinosinusitis (ICARâRS) has witnessed foundational progress in our understanding and treatment of rhinologic disease. These advances are reflected within the more than 40 new topics covered within the ICARâRSâ2021 as well as updates to the original 140 topics. This executive summary consolidates the evidenceâbased findings of the document. Methods: ICARâRS presents over 180 topics in the forms of evidenceâbased reviews with recommendations (EBRRs), evidenceâbased reviews, and literature reviews. The highest grade structured recommendations of the EBRR sections are summarized in this executive summary. Results: ICARâRSâ2021 covers 22 topics regarding the medical management of RS, which are grade A/B and are presented in the executive summary. Additionally, 4 topics regarding the surgical management of RS are grade A/B and are presented in the executive summary. Finally, a comprehensive evidenceâbased management algorithm is provided. Conclusion: This ICARâRSâ2021 executive summary provides a compilation of the evidenceâbased recommendations for medical and surgical treatment of the most common forms of RS
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