다중혈관 관상동맥 환자에서 y-문합을 이용하여 양쪽 내흉동맥만을 사용한 우회술의 조기 성적

抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1（PfPMP1）与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用，在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员，通过启动转录不同的var基因变异体为抗原变异提供了分子基础。

疟原虫var基因转换速率变化导致抗原变异[英]／Paul H, Robert P, Christodoulou Z, et al//Proc Natl Acad Sci U S A

[신간의 별자리x] 우리/미술, 그리고 ‘슬픔의 박물관’

Metamaterials, or engineered materials with rationally designed, subwavelength-scale building blocks, allow us to control the behavior of physical fields in optical, microwave, radio, acoustic, heat transfer, and other applications with flexibility and performance that are unattainable with naturally available materials. In turn, metasurfaces-planar, ultrathin metamaterials-extend these capabilities even further. Optical metasurfaces offer the fascinating possibility of controlling light with surface-confined, flat components. In the planar photonics concept, it is the reduced dimensionality of the optical metasurfaces that enables new physics and, therefore, leads to functionalities and applications that are distinctly different from those achievable with bulk, multilayer metamaterials. Here, we review the progress in developing optical metasurfaces that has occurred over the past few years with an eye toward the promising future directions in the field.

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Planar Photonics with Metasurfaces

Subwavelength resolution imaging requires high numerical aperture (NA) lenses, which are bulky and expensive. Metasurfaces allow the miniaturization of conventional refractive optics into planar structures. We show that high-aspect-ratio titanium dioxide metasurfaces can be fabricated and designed as metalenses with NA = 0.8. Diffraction-limited focusing is demonstrated at wavelengths of 405, 532, and 660 nm with corresponding efficiencies of 86, 73, and 66%. The metalenses can resolve nanoscale features separated by subwavelength distances and provide magnification as high as 170×, with image qualities comparable to a state-of-the-art commercial objective. Our results firmly establish that metalenses can have widespread applications in laser-based microscopy, imaging, and spectroscopy.

Metalenses at visible wavelengths: Diffraction-limited focusing and subwavelength resolution imaging.

We report a new type of self-powered gas sensors based on the combination of a colorimetric film with hierarchical micro/nano-structures and organic photovoltaic cells. The transmittance of the col...

Self-Powered Gas Sensor Based on a Photovoltaic Cell and a Colorimetric Film with Hierarchical Micro/Nanostructures.

The optical spin Hall effect, which describes the spin-dependent and transverse shift of light, has been steadily investigated with the development of sensing applications such as polarization-dependent sensors, material interface analysis, and refractive index spectroscopy. However, practical optical spin Hall effect sensing platforms have not been reported since the previous reports have only focused on passive platforms. Here, we propose a biosensing platform using chitosan-coated all-dielectric metamaterials, which can detect the relative humidity of the surroundings by analyzing the displacement of the spin Hall effect. The chitosan coating provides a high sensitivity of relative humidity with a dynamic optical spin Hall effect in all-dielectric metamaterials. The maximum displacement of the split beam is calculated as 350 nm when the relative humidity changes by 60%, resulting in 8.75 nm shift per 1% of relative humidity change. This mechanism can be further exploited for a biosensing platform since the chitosan-coated all-dielectric metamaterials are biocompatible, biodegradable, and hydrophilic. Considering the chitosan-coated all-dielectric metamaterials have high feasibility with low-cost, high-throughput nanoimprinting methods, the dynamic optical spin Hall effect-based metamaterials will be a candidate of a promising real-time and ultra-sensitive sensing platform for detecting biomolecules.

Dynamic Optical Spin Hall Effect in Chitosan-Coated All-Dielectric Metamaterials for a Biosensing Platform

/pdf/experimental-demonstration-of-broadband-negative-refraction-idj4e5ke12.pdf

Experimental demonstration of broadband negative refraction at visible frequencies by critical layer thickness analysis in a vertical hyperbolic metamaterial

Engineering pseudo-spin and valley degrees of freedom using quantum spin Hall and valley Hall effects opens up remarkable possibilities for highly efficient and robust signal transport in time-reversal invariant photonic systems. Here, we present a spin-valley locked photonic crystal that has distinct signs of chirality of sublattices in a honeycomb unit cell. We show that the photonic crystal has an insulating bulk dispersion and sublattice-dependent spin-valley coupled gapless edge states by exploiting a coupled dipole method and demonstrate valley-selective propagation by controlling spin state of an external dipole source. The interplay between spin, valley and sublattice shows a judicious way for one-way photon transport by using multiple degrees of freedom.

https://iopscience.iop.org/article/10.1088/1367-2630/abc8ae/pdf

Spin-valley locked topological edge states in a staggered chiral photonic crystal

The inverse design of photonic devices through the training of artificial neural networks (ANNs) has been proven as an invaluable tool for researchers to uncover interesting structures and designs that produce optical devices with enhanced performance. Here, we demonstrate the inverse design of ultra-narrowband selective thermal emitters that operate in the wavelength regime of 2-8 µm using ANNs. By training the network on a dataset of around 200,000 samples, wavelength-selective thermal emitters are designed with an average mean squared error of less than 0.006. Q-factors as high as 109.2 are achieved, proving the ultra-narrowband properties of the thermal emitters. We further investigate the physical mechanisms of the designed emitters and characterize their angular responses to verify their use as thermal emitters for practical applications such as thermophotovoltaics, IR sensing and imaging, and infrared heating.

Junsuk Rho

Papers

Self-Powered Gas Sensor Based on a Photovoltaic Cell and a Colorimetric Film with Hierarchical Micro/Nanostructures.

Dynamic Optical Spin Hall Effect in Chitosan-Coated All-Dielectric Metamaterials for a Biosensing Platform

Experimental demonstration of broadband negative refraction at visible frequencies by critical layer thickness analysis in a vertical hyperbolic metamaterial

Spin-valley locked topological edge states in a staggered chiral photonic crystal

Inverse design of ultra-narrowband selective thermal emitters designed by artificial neural networks