Wavelength-selective metamaterial absorbers in the mid-infrared range are demonstrated by using multiple tungsten cross resonators. By adjusting the geometrical parameters of cross resonators in single-sized unit cells, near-perfect absorption with single absorption peak tunable from 3.5 µm to 5.5 µm is realized. The combination of two, three, or four cross resonators of different sizes in one unit cell enables broadband near-perfect absorption at mid-infrared range. The obtained absorption spectra exhibit omnidirectionality and weak dependence on incident polarization. The underlying mechanism of near-perfect absorption with cross resonators is further explained by the optical mode analysis, dispersion relation and equivalent RLC circuit model. Moreover, thermal analysis is performed to study the heat generation and temperature increase in the cross resonator absorbers, while the energy conversion efficiency is calculated for the thermophotovoltaic system made of the cross resonator thermal emitters and low-bandgap semiconductors.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1364/OE.26.005616 | DOI Listing |
Major Depressive Disorder (MDD) poses a significant public health challenge due to its high prevalence and the substantial burden it places on individuals and healthcare systems. Real-time functional magnetic resonance imaging neurofeedback (rtfMRI-NF) shows promise as a treatment for this disorder, although its mechanisms of action remain unclear. This study investigated whole-brain response patterns during rtfMRI-NF training to explain interindividual variability in clinical efficacy in MDD.
View Article and Find Full Text PDFLangmuir
December 2024
Key Laboratory of Functional Polymer Materials of Ministry of Education and College of Chemistry, Nankai University, Tianjin 300071, China.
Polyelectrolyte complex (PEC) hydrogels provide a promising strategy to develop a class of physically cross-linked networks characterized by exceptional toughness and self-healing properties. However, the precise control of the microstructure and the enhancement of mechanical properties still pose challenges in the field of PEC hydrogels. Herein, we propose a strategy to manipulate the structure of PEC with competitively charged surfactant micelles, leveraging the spatially confined surface charge and excluded volume effects to overcome coacervation issues associated with the PEC, thus achieving a simple one-step preparation of macroscopically uniform and tough PEC hydrogels.
View Article and Find Full Text PDFInvest Radiol
October 2024
From the Department of Radiology, Juntendo University School of Medicine, Tokyo, Japan (A.H., S.K., J.K., M.N., W.U., S.F., T.A., A.W., K.K., S.A.); Department of Radiology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan (A.H., M.N., S.F.); Polytechnique Montréal, Montreal, Quebec, Canada (S.N.); Montreal Heart Institute, University of Montreal, Montreal, Quebec, Canada (S.N.); and Center for Advanced Interdisciplinary Research, Ss. Cyril and Methodius University in Skopje, Skopje, North Macedonia (S.N.).
The aging process induces a variety of changes in the brain detectable by magnetic resonance imaging (MRI). These changes include alterations in brain volume, fluid-attenuated inversion recovery (FLAIR) white matter hyperintense lesions, and variations in tissue properties such as relaxivity, myelin, iron content, neurite density, and other microstructures. Each MRI technique offers unique insights into the structural and compositional changes occurring in the brain due to normal aging or neurodegenerative diseases.
View Article and Find Full Text PDFPaediatr Drugs
December 2024
Division of Neurology, Department of Pediatrics, The Hospital for Sick Children, 555 University Avenue, Toronto, ON, M5G 1X8, Canada.
Pediatric-onset multiple sclerosis (POMS) refers to multiple sclerosis with onset before 18 years of age. It is characterized by a more inflammatory course, more frequent clinical relapses, and a greater number of magnetic resonance imaging (MRI) lesions compared with adult-onset MS (AOMS), leading to significant impacts on both disability progression and cognitive outcomes in affected individuals. Managing POMS presents distinct challenges due to the unique needs of pediatric patients and the limited number of disease-modifying therapies (DMTs) approved for pediatric use.
View Article and Find Full Text PDFACS Food Sci Technol
December 2024
Department of Food Engineering, Middle East Technical University (METU), Ankara 06800, Turkey.
Noncentrifugal sugar (NCS) is an unrefined, dark brown sugar containing minerals and plant secondary metabolites, unlike refined white sugar (WS). This study explored using NCS in confectionary jellies as an alternative sugar. We used different concentrations of NCS and WS to prepare low methoxyl pectin (LMP) confectionery gels characterized by their physical and rheological properties along with time-domain nuclear magnetic resonance (TD-NMR) relaxometry.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!