Hyper-parameter selection in non-quadratic regularization-based radar image formation

We consider the problem of automatic parameter selection in regularization-based radar image formation techniques. It has previously been shown that non-quadratic regularization produces feature-enhanced radar images; can yield superresolution; is robust to uncertain or limited data; and can generate enhanced images in non-conventional data collection scenarios such as sparse aperture imaging. However, this regularized imaging framework involves some hyper-parameters, whose choice is crucial because that directly affects the characteristics of the reconstruction. Hence there is interest in developing methods for automatic parameter choice. We investigate Stein’s unbiased risk estimator (SURE) and generalized cross-validation (GCV) for automatic selection of hyper-parameters in regularized radar imaging. We present experimental results based on the Air Force Research Laboratory (AFRL) “Backhoe Data Dome,” to demonstrate and discuss the effectiveness of these methods

Parameter selection in sparsity-driven SAR imaging

We consider a recently developed sparsity-driven synthetic aperture radar (SAR) imaging approach which can produce superresolution, feature-enhanced images. However, this regularization-based approach requires the selection of a hyper-parameter in order to generate such high-quality images. In this paper we present a number of techniques for automatically selecting the hyper-parameter involved in this problem. In particular, we propose and develop numerical procedures for the use of Stein’s unbiased risk estimation, generalized cross-validation, and L-curve techniques for automatic parameter choice. We demonstrate and compare the effectiveness of these procedures through experiments based on both simple synthetic scenes, as well as electromagnetically simulated realistic data. Our results suggest that sparsity-driven SAR imaging coupled with the proposed automatic parameter choice procedures offers significant improvements over conventional SAR imaging

Sparsity-driven spatio-temporal EEG source estimation (Seyreklik tabanlı uzam-zamansal EEG kaynak kestirimi)

We consider the problem of sparse source estimation using multiple time samples. We propose the use of a spatio-temporal constraint which is a combination of spatial ℓ1-norm for sparsity and temporal ℓ2-norm for nonspiky pattern in time. We demonstrate the effectiveness of this spatio-temporal method through experiments based on both simulated and human EEG data

İleri sentetik açıklıklı radar görüntüleme algoritmalarında parametre seçimi = Hyper-parameter selection in advanced synthetic aperture radar imaging slgorithms

We consider the problem of hyper-parameter selection in advanced image reconstruction algorithms used in synthetic aperture radar (SAR) imaging. To deal with the parameter selection problem in these algorithms, we propose the use of unbiased predictive risk estimation and generalized cross-validation techniques. We demonstrate the effectiveness of the applied methods through experiments based on electromagnetically simulated realistic data

ADHESIVE SYSTEM AFFECTS REPAIR BOND STRENGTH OF RESIN COMPOSITE

Purpose: This study evaluated the effects of different adhesive systems on repair bond strength of aged resin composites

Randomized controlled trial of the 2-year clinical performance of a silorane-based resin composite in class 1 posterior restorations

Purpose: To compare the 2-year clinical performance of a silorane-based resin composite with that of an established nanoceramic resin composite for class 1 posterior restorations. Methods: In this randomized controlled study, 100 class 1 molar cavities were prepared in 50 subjects. Each subject received a restoration with Filtek Silorane and Ceram.X Duo in different quadrants. The restorations were evaluated using the modified USPHS criteria at baseline and 6, 12, and 24 months. Parametric changes over the 2-year period were assessed with the Friedman test. The baseline and recall scores were compared by using the Wilcoxon signed-rank test (P 0.05). At 2 years, four Filtek Silorane and seven Ceram.X Duo restorations had Bravo scores for anatomic form, marginal adaptation, and surface texture (P< 0.05); however, these changes were mainly the effect of scoring shifts from Alfa to Bravo. Overall, both materials showed good clinical results with predominantly Alfa scores

In vitro evaluation of effects of sustained anti-TNF release from MPEG-PCL-MPEG and PCL microspheres on human rheumatoid arthritis synoviocytes

Anti-tumor necrosis factor (TNF) drugs such as etanercept (ETN) have been mostly used in systemic treatment of rheumatoid arthritis. To eliminate the side effects in long-term treatments and to achieve a local sustained anti-inflammatory effect, a controlled drug delivery system is needed for anti-TNF drugs. This study aims to develop novel injectable microcarriers of ETN that can provide long-term controlled release of this protein drug upon intra-articular application. In this study, poly(epsilon-caprolactone) (PCL) and its copolymer with poly(ethylene glycol), methoxypoly(ethylene glycol)-poly(epsilon-caprolactone)-methoxypoly(ethylene glycol) microspheres (MPEG-PCL-MPEG) were compared for their prospective success in rheumatoid arthritis treatment. Microspheres with smooth surface of a mean particle diameter of approximately 5m were prepared with both polymers. MPEG-PCL-MPEG microspheres had higher encapsulation efficiency than PCL microspheres. The activity of encapsulated ETN within MPEG-PCL-MPEG microspheres also retained while 90% of the activity of ETN within PCL microspheres could retain during 90-day release. MPEG-PCL-MPEG microspheres showed faster ETN release compared to PCL microspheres in various release media. Cumulative amounts of ETN released from both types of microspheres were significantly lower in cell culture medium and in synovial fluids than in phosphate buffered saline. This was mainly due to protein adsorption onto microspheres. Hydrophilic MPEG segment enhanced ETN release while preventing protein adsorption on microspheres compared to PCL. Sustained ETN release from microspheres resulted with a significant decrease in pro-inflammatory cytokines (TNF, IFN, IL-6, IL-17) and MMP levels (MMP-3, MMP-13), while conserving viability of fibroblast-like synoviocytes compared to the free drug. Results suggest that MPEG-PCL-MPEG is a potential copolymer of PCL that can be used in development of biomedical materials for effective local treatment purposes in chronic inflammatory arthritis owing to enhanced hydrophilicity. Yet, PCL microspheres are also promising systems having good compatibility to synoviocytes and would be especially the choice for treatment approach requiring longer term and slower release

The Effect of Biologics in the Treatment of Multisystem Inflammatory Syndrome in Children (Mis-C): A Single-Center Propensity-Score-Matched Study

Multisystem inflammatory syndrome in children (MIS-C) is a serious condition characterized by excessive inflammation that can arise as a complication of SARS-CoV-2 infection in children. While our understanding of COVID-19 and MIS-C has been advancing, there is still uncertainty regarding the optimal treatment for MIS-C. In this study, we aimed to compare the clinical and laboratory outcomes of MIS-C patients treated with IVIG plus corticosteroids (CS) to those treated with IVIG plus CS and an additional biologic drug. We used the propensity score (PS)-matching method to assess the relationships between initial treatment and outcomes. The primary outcome was a left ventricular ejection fraction of less than 55% on day 2 or beyond and/or the requirement of inotrope support on day 2 or beyond. We included 79 MIS-C patients (median age 8.51 years, 33 boys) followed in our center. Among them, 50 children (25 in each group) were allocated to the PS-matched cohort sample. The primary outcome was observed in none of the patients in the IVIG and CS group, while it occurred in eight patients in the IVIG plus CS and biologic group (p = 0.04). MIS-C is a disorder that may progress rapidly and calls for extensive care. For definitive recommendations, further studies, including randomized control trials, are required

The clinical course of SARS-CoV-2 infection among children with rheumatic disease under biologic therapy: a retrospective and multicenter study.

The effects of biological disease-modifying antirheumatic drugs (bDMARDs) in the clinical course of COVID-19 on children with underlying rheumatologic diseases have not been fully demonstrated. To evaluate the course of COVID-19 infection in patients with rheumatic disease receiving bDMARD treatment. This was a retrospective, multicenter study conducted in pediatric patients infected by SARS-CoV-2 and under bDMARDs therapy. The study population consisted of 113 patients (72 female/41 male). The mean age of the patients was 12.87 +/- 4.69 years. The primary diagnosis of the cohort was as follows: 63 juvenile idiopathic arthritis, 35 systemic autoinflammatory diseases, 10 vasculitides, and five cases of connective tissue diseases. The mean duration of the primary disease was 4.62 +/- 3.65 years. A total of 19 patients had additional comorbid diseases. Thirty-five patients were treated with canakinumab, 25 with adalimumab, 18 with etanercept, 10 with infliximab, nine with tocilizumab, six with rituximab, four with anakinra, three with tofacitinib, and one with abatacept. The median exposure time of the biological drug was 13.5 months. Seventy-one patients had symptomatic COVID-19, while 42 were asymptomatic. Twenty-four patients required hospitalization. Five patients presented with MIS-C. The hospitalized patients were younger and had a shorter duration of rheumatic disease compared to ambulatory patients, although the difference was not statistically significant. Steroid usage, presence of fever, and dyspnea were more common among the hospitalized patients. A worsening in the course of both COVID-19 and current disease was not noticed under bDMARDs, however, to end with a strong conclusion multicentric international studies are required