Several observational studies have reported an association between obesity and primary liver cancer (PLC), while the causality behind this association and the comparison of the risk effects of ...different obesity indicators on PLC remain unclear. In this study, we performed two‐sample Mendelian randomization (MR) analyses to assess the associations of genetically determined liver fat, visceral adipose tissue (VAT), and body mass index (BMI) with the risk of PLC. The summary statistics of exposures were obtained from two genome‐wide association studies (GWASs) based on the UK Biobank (UKB) imaging cohort and the Genetic Epidemiology Research on Adult Health and Aging (GERA) cohort. GWAS summary statistics for PLC were obtained from FinnGen consortium R7 release data, including 304 PLC cases and 218 488 controls. Inverse‐variance weighted (IVW) was used as the primary analysis, and a series of sensitivity analyses were performed to further verify the robustness of these findings. IVW analysis highlighted a significant association of genetically determined liver fat (OR per SD increase: 7.14; 95% CI: 5.10‐9.99; P = 2.35E‐30) and VAT (OR per SD increase: 5.70; 95% CI: 1.32‐24.72; P = .020) with PLC but not of BMI with PLC. The findings were further confirmed by a series of MR methods. No evidence of horizontal pleiotropy between these associations existed. Our study suggested that genetically determined liver fat and VAT rather than BMI were associated with an increased risk of PLC, which suggested that visceral fat distribution is more predictive of the clinical risk of PLC than common in vitro measures.
What's new?
Obesity is associated with increased risk of primary liver cancer (PLC). However, the causality of obesity in PLC is difficult to determine based on existing observational studies, and little is known about whether specific fat distribution impacts PLC risk. Here, the authors employed Mendelian randomization to investigate associations between PLC risk and genetically determined liver fat deposition and visceral fat distribution. Genetically predicted liver fat and visceral adipose tissue (VAT) distribution were more strongly linked to increased PLC risk than body mass index. VAT and especially fat deposition in the liver are promising clinical measures for predicting PLC risk.
Birefringence occurs when light with different polarizations sees different refractive indices during propagation. It plays an important role in optics and has enabled essential polarization elements ...such as wave plates. In bulk crystals, it is typically constrained to linear birefringence. In metamaterials with freeform meta-atoms, however, one can engineer the optical anisotropy such that light sees different indices for arbitrary-linear, circular, or elliptical-orthogonal eigen-polarization states. Using topology-optimized metasurfaces, we demonstrate this arbitrary birefringence. It has the unique feature that it can be continuously tuned from linear to elliptical birefringence, by changing the angle of incidence. In this way, a single metasurface can operate as many wave plates in parallel, implementing different polarization transformations. Angle-tunable arbitrary birefringence expands the scope of polarization optics, enables compact and versatile polarization operations that would otherwise require cascading multiple elements, and may find applications in polarization imaging, quantum optics, and other areas.
Existing methods of correcting for chromatic aberrations in optical systems are limited to two approaches: varying the material dispersion in refractive lenses or incorporating grating dispersion via ...diffractive optical elements. Recently, single-layer broadband achromatic metasurface lenses have been demonstrated but are limited to diameters on the order of 100 μm due to the large required group delays. Here, we circumvent this limitation and design a metacorrector by combining a tunable phase and artificial dispersion to correct spherical and chromatic aberrations in a large spherical plano-convex lens. The tunability results from a variation in light confinement in sub-wavelength waveguides by locally tailoring the effective refractive index. The effectiveness of this approach is further validated by designing a metacorrector, which greatly increases the bandwidth of a state-of-the-art immersion objective (composed of 14 lenses and 7 types of glasses) from violet to near-infrared wavelengths. This concept of hybrid metasurface-refractive optics combines the advantages of both technologies in terms of size, scalability, complexity, and functionality.
Holograms, the optical devices to reconstruct predesigned images, show many applications in our daily life. However, applications of hologram are still limited by the constituent materials and ...therefore their working range is trapped at a particular electromagnetic region. In recent years, the metasurfaces, an array of subwavelength antenna with varying sizes, show the abilities to manipulate the phase of incident electromagnetic wave from visible to microwave frequencies. Here, we present a reflective-type and high-efficiency meta-hologram fabricated by metasurface for visible wavelength. Using gold cross nanoantennas as building blocks to construct our meta-hologram devices with thickness ∼ λ/4, the reconstructed images of meta-hologram show polarization-controlled dual images with high contrast, functioning for both coherent and incoherent light sources within a broad spectral range and under a wide range of incidence angles. The flexibility demonstrated here for our meta-hologram paves the road to a wide range of applications related to holographic images at arbitrary electromagnetic wave region.
Metal-free organic phosphorescent materials have attracted considerable attention in the fields of organic electronics and bioelectronics. However, it remains a great challenge to achieve organic ...phosphors with high quantum efficiency in a single-component system. We designed and synthesized two organic phosphors (PDCz and PDBCz) with an ultralong organic phosphorescence (UOP) feature. Both molecules showed ultralong emission lifetime of >200 ms. For PDBCz crystal, it was found that the absolute phosphorescence quantum efficiency reaches up to 38.1%. Combining the experimental and theoretical studies, the highly efficient UOP was mainly attributed to the intramolecular space heavy-metal effect, which facilitates the spin–orbit coupling between singlet and triplet excited states to effectively promote the intersystem crossing. This study will provide a new platform to rationally design highly efficient UOP materials and show its potential in the field of flexible electronics.
The toroidal dipole is a localized electromagnetic excitation independent from the familiar magnetic and electric dipoles. It corresponds to currents flowing along minor loops of a torus. ...Interference of radiating induced toroidal and electric dipoles leads to anapole, a nonradiating charge-current configuration. Interactions of induced toroidal dipoles with electromagnetic waves have recently been observed in artificial media at microwave, terahertz, and optical frequencies. Here, we demonstrate a quasi-planar plasmonic metamaterial, a combination of dumbbell aperture and vertical split-ring resonator, that exhibits transverse toroidal moment and resonant anapole behavior in the optical part of the spectrum upon excitation with a normally incident electromagnetic wave. Our results prove experimentally that toroidal modes and anapole modes can provide distinct and physically significant contributions to the absorption and dispersion of slabs of matter in the optical part of the spectrum in conventional transmission and reflection experiments.
•A novel combinational strategy was proposed for drag and heat reduction.•The accuracy of the numerical method was validated.•Drag and heat reduction mechanism of combinational strategy was ...analyzed.•Effects of design parameters of spike, nozzle and aerodisk were evaluated.
A novel combinational configuration is proposed for drag and heat reduction in this paper, the CFD numerical method is adopted to study its drag and heat reduction performance. The results show that the aerodisk enhances the compression of hypersonic free stream by the spike to reduce the intensity of reattachment shock wave. The rear jet pushes the reattachment shock wave away from the blunt body and reduce the intensity of reattachment shock wave as well. In addition, the low-temperature gas from rear jet can also cool the blunt body directly. Increasing the length-diameter ratio of the spike reduces the intensity of reattachment shock wave, the rear jet gas can be ejected farther to push the reattachment shock wave father away from the blunt body. Increasing the diameter of aerodisk enhances the compression of hypersonic free stream to reduce the intensity of reattachment shock wave, while the shock wave drag of spike gradually increases. Therefore, with the increase of diameter of aerodisk, the total drag coefficient of combinational configuration first decreases and then increases. The rear jet presents the long penetration mode and short penetration mode. Increasing the total pressure ratio and the size of nozzle can push the reattachment shock wave away from the blunt body and reduce the intensity of reattachment shock wave, more low-temperature gas can also be injected into the flow field to cool the blunt body effectively. Finally, the flat disk has better drag and heat reduction performance than conical disk and hemispherical disk.
In this study, we evaluated the efficacy of hydroxychloroquine (HCQ) against coronavirus disease 2019 (COVID-19) via a randomized controlled trial (RCT) and a retrospective study.
Subjects admitted ...to 11 designated public hospitals in Taiwan between April 1 and May 31, 2020, with COVID-19 diagnosis confirmed by pharyngeal real-time RT-PCR for SARS-CoV-2, were randomized at a 2:1 ratio and stratified by mild or moderate illness. HCQ (400 mg twice for 1 d or HCQ 200 mg twice daily for 6 days) was administered. Both the study and control group received standard of care (SOC). Pharyngeal swabs and sputum were collected every other day. The proportion and time to negative viral PCR were assessed on day 14. In the retrospective study, medical records were reviewed for patients admitted before March 31, 2020.
There were 33 and 37 cases in the RCT and retrospective study, respectively. In the RCT, the median times to negative rRT-PCR from randomization to hospital day 14 were 5 days (95% CI; 1, 9 days) and 10 days (95% CI; 2, 12 days) for the HCQ and SOC groups, respectively (p = 0.40). On day 14, 81.0% (17/21) and 75.0% (9/12) of the subjects in the HCQ and SOC groups, respectively, had undetected virus (p = 0.36). In the retrospective study, 12 (42.9%) in the HCQ group and 5 (55.6%) in the control group had negative rRT-PCR results on hospital day 14 (p = 0.70).
Neither study demonstrated that HCQ shortened viral shedding in mild to moderate COVID-19 subjects.
Smart materials with ultralong phosphorescence are rarely investigated and reported. Herein we report on a series of molecules with unique dynamic ultralong organic phosphorescence (UOP) features, ...enabled by manipulating intermolecular interactions through UV light irradiation. Our experimental data reveal that prolonged irradiation of single‐component organic phosphors of PCzT, BCzT, and FCzT under ambient conditions can activate UOP with emission lifetimes spanning from 1.8 to 1330 ms. These phosphors can also be deactivated back to their original states with short‐lived phosphorescence by UV irradiation for 3 h at room temperature or through thermal treatment. Additionally, the dynamic UOP was applied successfully for a visual anti‐counterfeiting application. These findings may provide unique insight into dynamic molecular motion for optical processing and expand the scope of smart‐response materials for broader applications.
Now you see it… now you don't: Prolonged irradiation of single‐component organic phosphors (see general structure) activated ultralong organic phosphorescence (UOP) with emission lifetime increasing from 1.8 to 1330 ms by altering their intermolecular interactions. The phosphors could be deactivated by UV irradiation for 3 h or heating. A multilevel anti‐counterfeiting application was demonstrated by using several phosphors with different UOP properties (see picture).
As a promising surface treatment technique, low‐temperature plasma (LTP) technology has been widely used over the past two decades. Herein, the surface modification of carbon materials using LTP ...treatment is reviewed to clarify the modification effects. First, the basic details of LTP treatment are summarized. Second, the surface morphology, pore structure, surface chemistry, adsorption performance, and catalytic characteristics of LTP‐treated carbon materials are reviewed. Finally, the research required to further develop LTP technology for the surface modification of carbon materials is discussed. This review will contribute toward advancing the application of LTP‐treated carbon materials in environmental pollution control.
The matrix properties of carbon materials (CMs) are not affected by low‐temperature plasma treatment. The surface physicochemical properties of CMs are influenced via a combination of plasma etching and surface functional group grafting effects. The performance of pollutants removal is improved by modifying CMs, which is explained in terms of the changes in surface chemistry properties.