Relationship between long-term PM2.5 exposure and myopia prevalence in adults: analysis of the Korea National Health and Nutrition Examination Survey-Air Pollution Linked Data, 2020.

Background: PM2.5 (particulate matter less than 2.5 μm) causes various health problems.

Association of weight and dietary habits with high blood mercury levels in Korean adolescents: data from the KoNEHS cycle 4, 2018-2020.

Background: Humans are exposed to mercury primarily in its highly toxic form, methyl mercury, which is known to have adverse effects on various organs and systems. The negative impact of mercury exposure on the growth, development, and mental health of children, from infancy to adolescence, is well-documented. However, there are no internationally standardized safe limits for mercury exposure.

Multi-microjoule broadband terahertz generation in the organic crystal BNA pumped by ytterbium laser pulses compressed via a gas-filled hollow-core fiber.

We investigate the enhanced terahertz generation in the organic crystal BNA when pumped by compressed high-energy ytterbium laser pulses. By compressing the pump pulses from 170 fs down to 43 fs using an argon-filled hollow-core fiber and chirped mirrors, the terahertz conversion efficiency is increased by 2.4 times, leading to the generation of multi-microjoule terahertz pulses with a frequency spectrum almost twice as wide, extending up to 19 THz.

Shape dependence of all-dielectric terahertz metasurface.

All-dielectric metasurfaces have been attracting attention in the terahertz spectral range for low-loss planar optical elements such as lenses, beam splitters, waveplates, vortex plates, and magnetic mirrors. Various shapes of meta-atoms have been used in many studies; however, no systematic comparative study of each shape has been reported. The optical properties of various shapes of metasurfaces are reported in this work using finite difference time domain simulation.

Two-dimensionally grown single-crystal silicon nanosheets with tunable visible-light emissions.

Since the discovery of graphene, growth of two-dimensional (2D) nanomaterials has greatly attracted attention. However, spontaneous growth of atomic two-dimensional (2D) materials is limitedly permitted for several layered-structure crystals, such as graphene, MoS2, and h-BN, and otherwise it is notoriously difficult. Here we report the gas-phase 2D growth of silicon (Si), that is cubic in symmetry, via dendritic growth and an interdendritic filling mechanism and to form Si nanosheets (SiNSs) of 1 to 13 nm in thickness.