The Gut-Eye Axis: Correlation Between the Gut Microbiota and Autoimmune Dry Eye in Individuals With Sjögren Syndrome.

ABSTRACT: The impact of gut microbiota on human health, autoimmunity, and disease occurrence has long been recognized since the advancement of metagenomic sequencing technology has enabled a new level of perspective on the human microbiome. Emerging findings also suggest the existence of a gut-eye axis, wherein gut dysbiosis may be a crucial factor affecting the onset and progression of multiple ocular diseases. Sjögren syndrome (SS) is a chronic autoimmune disease mainly affecting the exocrine glands, primarily the lacrimal gland in the eye, resulting in severe dry eye. Although there are currently various treatments for environmental dry eye, the efficacy for SS-related autoimmune dry eye is limited, and new and more effective therapies still need to be explored. The latest studies have demonstrated that the gut microbiota plays a key role in the pathogenesis of autoimmune dry eye. This review describes the effect of gut microbiota on the ocular surface of autoimmune dry eye; introduces the presumable pathways forming the "gut dysbiosis-ocular surface-lacrimal gland axis"; discusses the advantages of restoring intestinal microecology to treat dry eye by fecal microbiota transplantation or probiotics, which are expected to provide perspectives into the correlation between the gut microbiome and dry eye; enhance our understanding of the pathogenesis in autoimmune dry eye; and be useful in the development of future interventions of dry eye by regulating the gut microbiota.

Dual-channel geometric meta-holograms with complex-amplitude modulation based on bi-spectral single-substrate-layer meta-atoms.

Metasurfaces with complex-amplitude modulation are superior in power regulation and hologram imaging resolution compared with those with phase-only modulation. Nevertheless, a single-cell metasurface with multi-band independent phase and amplitude controls is still a great challenge for the circularly polarized incidences. In this work, we propose and design a single-substrate-layer single-cell metasurface with independent complex-amplitude modulations at two discrete frequencies. Based on this emerging technique, a bi-spectral meta-hologram is designed and verified by both full-wave simulations and experiments, which could reconstruct two Chinese characters at the imaging plane at two frequencies. The proposed method shows great potential in multifunctional meta-devices with enhanced performance.

Reconfigurable multi-band water-graphene cascade metamaterial perfect absorbers loaded with vanadium dioxide.

We demonstrate the perfect trapping of electromagnetic fields over multi-band frequencies through all-dielectric terahertz absorbers using water graphene cascade metamaterials. More specifically, the coating water layer greatly enhances the higher-order Fabry-Pérot resonant absorbing modes and can achieve more than 8 absorbing peaks with the absorptions exceeding 99% in the spectrum below 3 THz. Especially such multiple perfect absorbing bands can readily be reset when the proposed water-graphene metamaterial absorbers integrate with thermal controlled vanadium dioxide. Such a perfect absorbing capacity would also be valid for the wide angular illuminations with different polarizations, and the reconfigurable characteristics of graphene can also enable the dynamically tuning of the absorbing frequencies, offering great freedom of extensive applications in energy harvesting and wave manipulation.

Time-Modulated Transmissive Programmable Metasurface for Low Sidelobe Beam Scanning.

Programmable metasurfaces have great potential for the implementation of low-complexity and low-cost phased arrays. Due to the difficulty of multiple-bit phase control, conventional programmable metasurfaces suffer a relatively high sidelobe level (SLL). In this manuscript, a time modulation strategy is introduced in the 1-bit transmissive programmable metasurface for reducing the SLLs of the generated patterns. After the periodic time modulation, harmonics are generated in each reconfigurable unit and the phase of the first-order harmonic can be dynamically controlled by applying different modulation sequences onto the corresponding unit. Through the high-speed modulation of the real-time periodic coding sequences on the metasurface by the programmable bias circuit, the equivalent phase shift accuracy to each metasurface unit can be improved to 6-bit and thus the SLLs of the metasurface could be reduced remarkably. The proposed time-modulated strategy is verified both numerically and experimentally with a transmissive programmable metasurface, which obtains an aperture efficiency over 34% and reduced SLLs of about -20 dB. The proposed design could offer a novel approach of a programmable metasurface framework for radar detection and secure communication applications.

Switchable metasurface for nearly perfect reflection, transmission, and absorption using PIN diodes.

Active metasurfaces with dynamically switchable functionalities are highly in demands in various practical applications. In this paper, we experimentally present an active metasurface based on PIN diodes which can realize nearly perfect reflection, transmission and absorption in a single design. Such switchable functionalities are accomplished by controlling the PIN diodes integrated in both layers of the metasurface. A transmission line model is employed to further investigate the underlying mechanism of the metasurface. This proposal is confirmed by numerical simulations and experiments. As a novel metasurface with multiple switchable functionalities, our design may find some practical applications such as smart radomes.

The association of serum lipid level with ischemic stroke in the elderly of Xinjiang.

BACKGROUND: The aim of the present study is to determine the association of serum lipid level in the above 55-year-old age elderly with ischemic stroke (IS) in Xinjiang regions, China. METHODS: 408 patients with IS and 347 healthy individuals as control in the ≥55-year-old elderly were selected for the present study in Xinjiang province of China from July 2010 to July 2012. Patients were divided into different groups according to the IS subtypes (large-artery atherosclerosis, LAA; cardio-aortic embolism CE; small-artery occlusion, SAO), plague stability, hypertension and diabetes. The serum lipid level including total cholesterol (TC), triglyceride (TG), high-density lipoprotein (HDL), low-density lipoprotein (LDL), apolipoprotein A1 (ApoA1), apolipoprotein B (ApoB), Lipoprotein(a) (Lp(a)) and their ratios(TC/HDL, LDL/HDL, ApoA1/ApoB) were measured. RESULTS: Patients in LAA group had higher ratio of TC/HDL, ApoA1/ApoB and lower level of ApoA1 than SAO group(p<0.05); higher level of TC, HDL, LDL, TC/HDL, LDL/HDL, ApoA1/ApoB and lower level of ApoB compared with CE group. Patients in SAO group had higher level of LDL, ApoA1, ApoB, TC/HDL, LDL/HDL and ApoA1/ApoB than CE group. Patients with stable plaque had higher level of HDL and low level of LDL, ApoB, Lp(a), TC/HDL, LDL/HDL and ApoA1/ApoB than unstable plaque group. Patients with hypertension had higher level of TG, ApoB, Lp(a), LDL/HDL and ApoA1/ApoB than non-hypertensive group. Patients with diabetes had higher level of TC, TG, ApoB, TC/HDL, LDL/HDL, ApoA1/ApoB and low level of ApoA1 than non-diabetic group. Multiple logistic regression analysis revealed that high LDL, ApoB, LDL/HDL and ApoA1/ApoB might be the risk factors for ischemic stroke. CONCLUSION: An abnormal serum lipid level of the patients with IS in older Xinjiang population is significantly associated with the stroke subtypes, plaque stability, hypertension and diabetes.

Experimental Array for Generating Dual Circularly-Polarized Dual-Mode OAM Radio Beams.

Recently, vortex beam carrying orbital angular momentum (OAM) for radio communications has attracted much attention for its potential of transmitting multiple signals simultaneously at the same frequency, which can be used to increase the channel capacity. However, most of the methods for getting multi-mode OAM radio beams are of complicated structure and very high cost. This paper provides an effective solution of generating dual circularly-polarized (CP) dual-mode OAM beams. The antenna consists of four dual-CP elements which are sequentially rotated 90 degrees in the clockwise direction. Different from all previous published research relating to OAM generation by phased arrays, the four elements are fed with the same phase for both left-hand circular polarization (LHCP) and right-hand circular polarization (RHCP). The dual-mode operation for OAM is achieved through the opposite phase differences generated for LHCP and RHCP, when the dual-CP elements are sequentially rotated in the clockwise direction. The measured results coincide well with the simulated ones, which verified the effectiveness of the proposed design.

Gene Polymorphisms Affect the Effectiveness of Atorvastatin in Treating Ischemic Stroke Patients.

BACKGROUND/AIMS: The aim of the present study is to investigate whether the single nucleotide polymorphism (SNP) in lipid metabolism related genes would affect the effectiveness of atorvastatin in both Han and Uighur populations. METHODS: 200 ischemic stroke patients were treated with atorvastatin. The differences of blood lipid level and their ratios were measured. Six lipid related genes, HMGCR, APOA5, LPL, CETP, LDLR and PCSK9 were selected as candidate genes. And nine SNP loci in these six genes were genotyped by SNaPshot technique. RESULTS: In all patients treated with atorvastatin, the SNP rs662799 significantly affected the ratio of x0394;LDL and x0394;LDL/LDL (p < 0.05); the SNP rs320 significantly affected the ratio of x0394;LDL/LDL and x0394;(LDL/HDL)/(LDL/HDL) (p < 0.01) and the SNP rs708272 significantly affected the ratio of x0394;LDL (p < 0.05). In Han population treated with atorvastatin, the SNP rs662799 significantly affected the ratio of x0394;TG (p < 0.05); the SNP rs320 significantly affected the ratio of x0394;LDL/LDL and x0394;(LDL/HDL)/(LDL/HDL) (p < 0.01). In Uighur population treated with atorvastatin, the SNP rs2266788 significantly affected the ratio of x0394;HDL (p < 0.05); the SNP rs662799 significantly affected the ratio of x0394;LDL/LDL (p < 0.05) and the SNP rs708272 significantly affected the ratio of x0394;LDL (p < 0.05). CONCLUSION: Polymorphisms of rs662799 and rs2266788 in APOA5 gene, rs320 in LPL gene and rs708272 in CETP gene had significant association with the effect of the lipid-lowering therapy via atorvastatin calcium on ischemic stroke patients.

Rotman Lens-Based Circular Array for Generating Five-mode OAM Radio Beams.

Recently, vortex beam carrying orbital angular momentum (OAM) for radio communications has attracted much attention for its potential of transmitting multiple signals simultaneously at the same frequency, which can be used to increase the channel capacity. However, most of the methods for getting multi-mode OAM radio beams remain up to now mainly at simulation level, since their implementations are of complicated structure and very high cost. This paper provides an effective design of generating five-mode OAM radio beams by using the Rotman lens-fed antenna array. The Rotman lens is a viable beamforming approach instead of electronically scanned arrays for its low cost and the ease of implementation. The lens-fed array employs a two-layer structure for size reduction, and the lens body and the antenna array are segregated by a common ground plane to eliminate spurious radiation and thus improve the performance of the OAM beams. The measured results coincide with the simulated ones, which verified the effectiveness of the proposed design for generating multi-mode OAM beams.