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 elucidated chain-extension effects of a benzodithiophene (BDT) and thienopyrroledione-based push–pull conjugated polymer (CP) on its exciton-dissociation mechanism within aggregate systems using transient absoption spectroscopy. The side-group extension CP with benzothiophene on the BDT unit induced H-type excitons with excess energy owing to decreased chain stiffness. This led to interchain polaron-pair (PP)-mediated exciton dissociation. The stiff side-group extended with thienothiophene on the BDT unit also induced H-type excitons, but the decreased energy and breadth of the density of states suppressed the interchain PP-mediated exciton dissociation. The main-chain-extension CP with two thiophenes on either side of the BDT unit has a curved structure disturbing the interchain packing. Thus, the driving force of exciton dissociation between the chains decreased, leading to intrachain PP-mediated exciton dissociation. Our findings can facilitate the development of novel CPs to further increase the efficiencies of polymer solar cells. 

Elucidating the Chain-Extension Effect on the Exciton-Dissociation Mechanism through an Intra- or Interchain Polaron-Pair State in Push–Pull Conjugated Polymers

The recent development of metasurfaces has enabled to make ultra-compact holographic displays and devices. In this talk, the design methodology, materials selection, multiplexing, dynamic modulation and conventional/practical fabrication for metasurfaces will be discussed in detail. 

Dynamic metasurfaces for holography and structural coloration

In this presentation, a new type of etalon for ultrafast colorimetric vapor sensor is introduced. The etalon consists of reflector, vapor-responsive hydrogel layer, and disordered plasmonic nanoparticles. This etalon presents dramatically fast gas-responsive time (~ 0.1s) because the disordered nanoparticles with certain ligand can form membrane pores smaller than the mean free path of penetrating gas. Among several candidates, thiocyanate ligand that provides optimized temporal and optical properties as effective medium is chosen. As a demonstration, the disordered nanoparticle-based etalon is applied to ultrafast humidity-responsive structural colors and an image sticker that instantaneously changes the displayed image to external humidity. 

Ultrafast colorimetric vapor sensors with disordered plasmonic nanoparticles

Tunable optical devices powered by metasurfaces provide a new path for functional planar optics. Lenses with tunable focal lengths could play a key role in various fields with applications in imaging, displays, and augmented and virtual reality devices. Here, we present a method for computationally designing an RGB-achromatic bifocal metalens and experimentally realize it through a scalable one-step nanoimprinting technique using a TiO2 nanoparticle embedded resin combined with an electrically tunable liquid crystal cell. 

Junsuk Rho

Papers

Elucidating the Chain-Extension Effect on the Exciton-Dissociation Mechanism through an Intra- or Interchain Polaron-Pair State in Push–Pull Conjugated Polymers

Dynamic metasurfaces for holography and structural coloration

Ultrafast colorimetric vapor sensors with disordered plasmonic nanoparticles

Tunable one-step nanoimprinted RGB-achromatic bifocal metalens

Disordered plasmonic nanoparticle-driven etalon for colorimetric gas sensor