Exploration of YBX1 role in the prognostic value and immune characteristics by single-cell and bulk sequencing analysis for liver hepatocellular carcinoma.

BACKGROUND: Y-box binding protein 1 (YBX1) plays a variety of roles in progression of multiple tumors. However, the role of YBX1 in prognostic value and immune regulation for liver hepatocellular carcinoma (LIHC) remains unclear. The present study aimed to examine the effect of YBX1 on the regulation of tumor immunity and survival prediction in LIHC patients. METHODS: YBX1-related expression profiles and single-cell and bulk sequencing analysis were performed using online databases. YBX1 expression was validated by a quantitative real-time PCR (qRT-PCR), western blotting and immunohistochemistry. Univariate/multivariate Cox regression analysis was performed to determine independent predictors of overall survival (OS). The ESTIMATE (i.e., Estimation of STromal and Immune cells in MAlignant Tumor tissues using Expression data) algorithm and Tumor Immune Dysfunction and Exclusion (TIDE) analysis were used to assess the relationships between YBX1 and LIHC immunity. RESULTS: YBX1 was over-expressed in LIHC tissues and cell lines. High YBX1 expression was significantly associated with poor OS. Univariate/multivariate Cox regression analysis revealed that YBX1 was an independent prognostic factor for LIHC. Gene set enrichment analysis revealed that YBX1 was associated with multiple signaling pathways correlated to LIHC. Additionally, YBX1 was expressed in multiple immune cells and was significantly correlated with immune cells, immune checkpoint markers and tumor immune microenvironment. The TIDE analysis demonstrated that LIHC patients with high YBX1 expression showed a higher T-cell dysfunction score and a higher exclusion score, as well as poorer immunotherapy response. CONCLUSIONS: YBX1 plays crucial oncogenic roles in LIHC and is closely associated with the immune defense system. YBX1 inhibition may serve as a potential treatment for LIHC.

MXene-Derived Na+ -Pillared Vanadate Cathodes for Dendrite-Free Potassium Metal Batteries.

Cation-intercalated vanadates, which have considerable promise as the cathode for high-performance potassium metal batteries (PMBs), suffer from structural collapse upon K+ insertion and desertion. Exotic cations in the vanadate cathode may ease the collapse, yet their effect on the intrinsic cation remains speculative. Herein, a stable and dendrite-free PMB, composed of a Na+ and K+ co-intercalated vanadate (NKVO) cathode and a liquid NaK alloy anode, is presented. A series of NKVO with tuneable Na/K ratios are facilely prepared using MXene precursors, in which Na+ is testified to be immobilized upon cycling, functioning as a structural pillar. Due to stronger ionic bonding and lower Fermi level of Na+ compared to K+ , moderate Na+ intercalation could reduce K+ binding to the solvation sheath and favor K+ diffusion kinetics. As a result, the MXene-derived Na+ -pillared NKVO exhibits markedly improved specific capacities, rate performance, and cycle stability than the Na+ -free counterpart. Moreover, thermally-treated carbon paper, which imitates the microscopic structure of Chinese Xuan paper, allows high surface tension liquid NaK alloy to adhere readily, enabling dendrite-free metal anodes. By clarifying the role of foreign intercalating cations, this study may lead to a more rational design of stable and high-performance electrode materials.

Endothelial KCa3.1 and KCa2.3 Mediate S1P (Sphingosine-1-Phosphate)-Dependent Vasodilation and Blood Pressure Homeostasis.

BACKGROUND: S1P (sphingosine-1-phosphate) has been reported to possess vasodilatory properties, but the underlying pathways are largely unknown. METHODS: Isolated mouse mesenteric artery and endothelial cell models were used to determine S1P-induced vasodilation, intracellular calcium, membrane potentials, and calcium-activated potassium channels (KCa2.3 and KCa3.1 [endothelial small- and intermediate-conductance calcium-activated potassium channels]). Effect of deletion of endothelial S1PR1 (type 1 S1P receptor) on vasodilation and blood pressure was evaluated. RESULTS: Mesenteric arteries subjected to acute S1P stimulation displayed a dose-dependent vasodilation response, which was attenuated by blocking endothelial KCa2.3 or KCa3.1 channels. In cultured human umbilical vein endothelial cells, S1P stimulated immediate membrane potential hyperpolarization following activation of KCa2.3/KCa3.1 with elevated cytosolic Ca2+. Further, chronic S1P stimulation enhanced expression of KCa2.3 and KCa3.1 in human umbilical vein endothelial cells in dose- and time-dependent manners, which was abolished by disrupting either S1PR1-Ca2+ signaling or downstream Ca2+-activated calcineurin/NFAT (nuclear factor of activated T-cells) signaling. By combination of bioinformatics-based binding site prediction and chromatin immunoprecipitation assay, we revealed in human umbilical vein endothelial cells that chronic activation of S1P/S1PR1 promoted NFATc2 nuclear translocation and binding to promoter regions of KCa2.3 and KCa3.1 genes thus to upregulate transcription of these channels. Deletion of endothelial S1PR1 reduced expression of KCa2.3 and KCa3.1 in mesenteric arteries and exacerbated hypertension in mice with angiotensin II infusion. CONCLUSIONS: This study provides evidence for the mechanistic role of KCa2.3/KCa3.1-activated endothelium-dependent hyperpolarization in vasodilation and blood pressure homeostasis in response to S1P. This mechanistic demonstration would facilitate the development of new therapies for cardiovascular diseases associated with hypertension.

The relationship between dyslipidemia and menopausal symptoms in Chinese menopausal women: a cross-sectional study.

OBJECTIVE: To investigate the relationship of dyslipidemia and menopausal symptoms in Chinese menopausal women. MATERIAL AND METHODS: A total of 989 eligible participants with menopausal syndrome were recruited from outpatient clinics in several cities in China. Menopausal symptoms were assessed using the Chinese Menopause Rating Scale (CMRS), the Self-rating Depression Scale (SDS), and the Self-rating Anxiety Scale (SAS). Serum lipid profile was measured using enzyme colorimetry. The relationship between lipid profile and menopausal symptoms was assessed using Student's t test/nonparametric Mann-Whitney U test, Spearman's correlation test, and binary logistic regression analysis. RESULTS: Among the 989 patients, 527 had dyslipidemia while 462 did not. Patients with dyslipidemia had significantly higher Self-rating Anxiety Scale (SAS) scores than those without (p < 0.001), while there was no significant difference in Self-rating Depression Scale (SDS) scores. Patients without dyslipidemia had higher scores on the Chinese Menopause Rating Scale (CMRS) vascular dimension compared to those with dyslipidemia (p = 0.003). The correlation test revealed that variables associated with dyslipidemia included age (p = 0.031), CMRS hot flashes dimension score (P = 0.003), and SAS score (p < 0.001). Regression analysis demonstrated that BMI (OR: 1.08, 95% CI: 1.01-1.16, p = 0.027), SAS scores (OR = 1.10, 95% CI = 1.07-1.13), vasomotor dimension (OR = 0.89, 95% CI = 0.83-0.95), physical dimension (OR = 0.96, 95% CI = 0.93-1.00), and social dimension (OR = 0.84, 95% CI = 0.74-0.95) were independently associated with an increased risk of dyslipidemia. CONCLUSIONS: This study showed that anxiety was associated with an unfavorable lipid profile, and menopausal depression seemed to have no relationship with lipid profile, while vasomotor symptoms appeared to be a favorable factor for dyslipidemia in Chinese menopausal women.

Effect of long-term care insurance policy on depression in non-disabled people: evidence from China.

BACKGROUND: Policy effect might be multidimensional and spill over to non-recipients. It is unclear how the implementation of Long-Term Care Insurance (LTCI) policy affects depression in non-disabled people and how this effect differs in different non-disabled groups. METHODS: Using time-varying differences-in-differences method and nationally representative health survey data in wave 2011, wave 2013, wave 2015 and wave 2018 from the China Health and Retirement Longitudinal Study, we assessed the effect of LTCI policy on depression in non-disabled people aged 45 years and older, and discussed the heterogeneity of effect across different population characteristics: retirement, financial support and social participation status. RESULTS: We found LTCI policy statistically significant reduced depression by 0.76 units in non-disabled people compared to non-pilot cities. Depression in non-disabled people who unretired, with financial support and without social participation was reduced by 0.8267, 0.7079 and 1.2161 units, respectively. CONCLUSIONS: Depression in non-disabled people was statistically significant reduced because of LTCI policy in China, and non-disabled people who unretired, with financial support and without social participation benefited more from LTCI policy. Our findings highlight the depression-reducing effect of LTCI policy in non-recipients and suggest that non-disabled people who unretired, with financial support and without social participation should be concerned during LTCI policy progress.

Characterization of driving factors for the long-term succession of bloom-forming cyanobacterial genera in Lake Erhai, southwest China.

Cyanobacterial blooms pose a global environmental concern, with various genera contributing to their formation. The harmfulness of cyanobacterial blooms varies depending on the specific genus, yet the factors triggering their formation remain incompletely understood. This study conducted qPCR of sediment DNA in Lake Erhai to reconstruct the historical succession of three common bloom-forming cyanobacterial genera (i.e., Microcystis, Dolichospermum, and Aphanizomenon). The driving factors and their corresponding thresholds were identified, and human activities related to driving factors were evaluated. The results revealed two successions in the past century. The first succession transitioned from Aphanizomenon (1902-1978) to Microcystis and Dolichospermum (1978-1999), driven by TN:TP and TP. The second succession shifted from Microcystis and Dolichospermum (1978-1999) to Microcystis (1999-2010), driven by TP, TN:TP, and temperature. The thresholds of TP and TN:TP for the Microcystis bloom were 0.023 mg/L and 17, respectively. TN:TP was significantly influenced by domestic pollution and crop farming in both successions, while TP was significantly impacted by domestic pollution in the first succession and by pollution from crop and dairy farming in the second succession. These results shed light on the underlying mechanism responsible for the blooms of various cyanobacterial genera and could serve as a valuable reference for effectively preventing and controlling nutrient input in the watershed.

Performance Degradation of a Double-Perovskite PrBaCo2O5+δ Cathode Operating under a CO2/H2O-Containing Atmosphere.

The electrochemical activity and stability of the PBCO electrode are investigated under the annealing processes in an atmosphere containing CO2/H2O for solid oxide fuel cells (SOFCs). The electrochemical impedance spectrum results unequivocally confirm the significant deterioration in PBCO cathode performance upon annealing under ambient air conditions, particularly when exposed to CO2/H2O atmospheres. Microstructure and surface chemical state analyses reveal the segregation of BaO on the PBCO surface, and the formation of insulating BaCO3 degraded the electrochemical performance. CO2 and H2O exhibit a significant induced effect on the segregation of Ba in PBCO to the surfaces, thereby causing a rapid decline in electrode performance. Additionally, the analysis of volume relaxation reveals that the presence of oxygen in the electrode environment can also influence the deposition process occurring on the surface of the electrode. However, this phenomenon is not observed in N2. This study emphasizes the impact of various gases present in the working atmosphere on surface-separated BaO, which consequently plays a pivotal role in the activity and long-term stability of PBCO electrodes.

Discovery of Melittin as Triple-Action Agent: Broad-Spectrum Antibacterial, Anti-Biofilm, and Potential Anti-Quorum Sensing Activities.

The development of antibiotic-resistant microorganisms is a major global health concern. Recently, there has been an increasing interest in antimicrobial peptides as a therapeutic option. This study aimed to evaluate the triple-action (broad-spectrum antibacterial, anti-biofilm, and anti-quorum sensing activities) of melittin, a membrane-active peptide present in bee venom. The minimum inhibitory concentration and minimum bactericidal concentration of the melittin were determined using the microdilution method and agar plate counting. Growth curve analysis revealed that melittin showed a concentration-dependent antibacterial activity. Scanning electron microscope analysis revealed that melittin treatment altered the morphology. Confocal laser scanning microscope revealed that melittin increased the membrane permeability and intracellular ROS generation in bacteria, all of which contribute to bacterial cell death. In addition, the crystal violet (CV) assay was used to test the anti-biofilm activity. The CV assay demonstrated that melittin inhibited biofilm formation and eradicated mature biofilms. Biofilm formation mediated by quorum sensing (QS) plays a major role in this regard, so molecular docking and molecular dynamics analysis confirmed that melittin interacts with LasR receptors through hydrogen bonds, and further evaluates the anti-QS activity of melittin through the production of virulence factors (pyocyanin, elastase, and rhamnolipid), exopolysaccharides secretion, and bacterial motility, that may be the key to inhibiting the biofilm formation mechanism. The present findings highlight the promising role of melittin as a broad-spectrum antibacterial, anti-biofilm agent, and potential QS inhibitor, providing a new perspective and theoretical basis for the development of alternative antibiotics.

Nb2 CTx MXene Derived Polymorphic Nb2 O5.

Previously, heat treatment was the only feasible route for tuning the crystal phases of niobium pentoxide (Nb2 O5 ). With the use of Nb2 CTx MXene precursors, the first case of phase tuning of Nb2 O5 in the low-temperature hydrothermal synthesis using sulfuric acid regulating agents is presented. By varying the amount of the agent, four pure-phase Nb2 O5 crystals and mixed phases in-between are obtained. The required amount is found to be related to the H-covered surface energy calculated based on density functional theory. Overall, MXene-derived B-phase Nb2 O5 is of particular interest due to its exceptionally high capacities as lithium-ion battery anodes, which are three times higher than the routine synthesized one. Oxygen vacancies induced by crystallographic shear would be responsible for the extraordinary performance. The proposed phase tuning strategy encourages the prudent synthesis of difficult-to-obtain crystal phases.

Health spillover studies of long-term care insurance in China: evidence from spousal caregivers from disabled families.

BACKGROUND: To alleviate the shortage of caregivers associated with disabled persons, China has implemented a pilot policy for long-term care insurance. This policy has the characteristics of "familialization" and "de-familialization" policy orientation, and it is indeed essential to clarify whether the policy has a positive spillover effect on the health of family caregivers, which is of great value to the pilot from local practice to national institutional arrangement. METHODS: Based on the China Health and Retirement Longitudinal Study microdata and time-varying DID method, our study used the implementation of the pilot policy as a "quasi-natural experiment" to assess the health spillover effects of the pilot policy on family spousal caregivers. RESULTS: This policy significantly improved the health of spousal caregivers, increasing self-rated health and life satisfaction, and reducing depression; Compared with female, urban and central-western spousal caregivers, male, rural and eastern spousal caregivers were "beneficiaries" in more dimensional health. CONCLUSIONS: Our research indicated that spousal caregivers of disabled people, particularly male, rural and eastern spousal caregivers, experienced positive health spillovers after implementing long-term care insurance. These results suggest that the imbalance between supply and demand of nursing staff could be solved in terms of de-familialization and familialization, spousal caregivers should be promoted to equally enjoy the policy benefits on gender, urban-rural and regions.

SPP excitation and coupling mechanism based on micro/nano fibers.

A hot trend in the development of optoelectronic devices is how to use the principle of surface plasmon resonance to enhance the performance of integrated photonics devices and achieve miniaturization. This paper proposes an accompanying waveguide coupling structure of micro/nano fibers, which consists of two parallel-placed micro/nano fibers (MNFs) coated with a silver film in the waist region and infused with a refractive index matching oil. In the overlapping region, there exists a segment of surface plasmon polaritons (SPPs) coupling area. The excitation and coupling characteristics of SPPs are studied through numerical simulation. Optimal coupling enhancement configuration is obtained by studying variables such as spacing distance, coupling length, and metal film thickness. A comparison is made with the SPP intensity of a single MNF, showing a 220% increase in electric field intensity, demonstrating its excellent coupling effect. By using this coupling structure, exploration of SPPs excitation and coupling mechanisms is enhanced, and structures resembling interferometric devices can be designed, providing new insights for high-performance miniaturized devices.

Altered m6A modification is involved YAP-mediated apoptosis response in 4-vinylcyclohexene diepoxide induced ovotoxicity.

4-Vinylcyclohexene diepoxide (VCD), an industrial occupational health hazard chemical associated with premature ovarian insufficiency (POI) and reproductive failure. Recently, investigators have paid an increasing attention on VCD model of menopause recapitulates the natural, physiological transition through perimenopause to menopause. The current study sought to examining the mechanisms of follicular loss and exploring the effect of the model on systems outside of the ovaries. In this study, 28 days female SD rats were injected with VCD (160 mg/kg) vehicle for 15 consecutive days, euthanized in the diestrus phase approximately 100 days after the onset of treatment. Reproductive system injury, Neuroendocrine, sex hormone levels and receptor were observed, the levels of N6-methyladenosine (m6A) RNA modification and the expression of modulator genes were first measured. The VCD treated rats showing irregular estrous cycles, significantly reduced in the number of primordial follicles, the preantral and antral follicles also decreased significantly, accompanied by the plasma level of FSH increased and anti-Mullerian hormone (AMH) were decreased. The total m6A level was significantly decreased after exposure to VCD. Moreover, ALKBH5-mediated YAP m6A modification changed in VCD - induced premature ovarian insufficiency. These present work provides a new perspective on m6A modification in the VCD-induced POI rat model, which could provide valuable insights into the mechanisms underlying follicle development and finding new therapeutic targets for follicle prematurely exhausted. Also provide novel methodological guidance and endocrine basis to guide research and extend the applications in premature ovarian insufficiency model.

[Ketogenic diet improves low temperature tolerance in mice by up-regulating PPARα in the liver and brown adipose tissue].

The aim of the present study was to investigate the effects of short-term ketogenic diet on the low temperature tolerance of mice and the involvement of peroxisome proliferator-activated receptor α (PPARα). C57BL/6J mice were divided into two groups: normal diet (WT+ND) group and ketogenic diet (WT+KD) group. After being fed with normal or ketogenic diet at room temperature for 2 d, the mice were exposed to 4 °C low temperature for 12 h. The changes in core temperature, blood glucose, blood pressure of mice under low temperature condition were detected, and the protein expression levels of PPARα and mitochondrial uncoupling protein 1 (UCP1) were detected by Western blot. PPARα knockout mice were divided into normal diet (PPARα-/-+ND) group and ketogenic diet (PPARα-/-+KD) group. After being fed with the normal or ketogenic diet at room temperature for 2 d, the mice were exposed to 4 °C low temperature for 12 h. The above indicators were also detected. The results showed that, at room temperature, the protein expression levels of PPARα and UCP1 in liver and brown adipose tissue of WT+KD group were significantly up-regulated, compared with those of WT+ND group. Under low temperature condition, compared with WT+ND, the core temperature and blood glucose of WT+KD group were increased, while mean arterial pressure was decreased; The ketogenic diet up-regulated PPARα protein expression in brown adipose tissue, as well as UCP1 protein expression in liver and brown adipose tissue of WT+KD group. Under low temperature condition, compared to WT+ND group, PPARα-/-+ND group exhibited decreased core temperature and down-regulated PPARα and UCP1 protein expression levels in liver, skeletal muscle, white and brown adipose tissue. Compared to the PPARα-/-+ND group, the PPARα-/-+KD group exhibited decreased core temperature and did not show any difference in the protein expression of UCP1 in liver, skeletal muscle, white and brown adipose tissue. These results suggest that the ketogenic diet promotes UCP1 expression by up-regulating PPARα, thus improving low temperature tolerance of mice. Therefore, short-term ketogenic diet can be used as a potential intervention to improve the low temperature tolerance.

Tunable and anisotropic perfect absorber using graphene-black phosphorus nanoblock.

Two-dimensional (2D) materials, which have attracted attention due to intriguing optical properties, form a promising building block in optical and photonic devices. This paper numerically investigates a tunable and anisotropic perfect absorber in a graphene-black phosphorus (BP) nanoblock array structure. The suggested structure exhibits polarization-dependent anisotropic absorption in the mid-infrared, with maximum absorption of 99.73% for x-polarization and 53.47% for y-polarization, as determined by finite-difference time-domain FDTD analysis. Moreover, geometrical parameters and graphene and BP doping amounts are possibly employed to tailor the absorption spectra of the structures. Hence, our results have the potential in the design of polarization-selective and tunable high-performance devices in the mid-infrared, such as polarizers, modulators, and photodetectors.

Individually tunable array reflector for amplitude and phase modulation.

Based on graphene's phase modulation property and vanadium dioxide's amplitude modulation property, we developed an array reflector for terahertz frequencies that is individually adjustable. Starting with a theoretical analysis, we look into the effects of voltage on the Fermi level of graphene and temperature on the conductivity of vanadium dioxide, analyze the beam focusing characteristics, and finally link the controllable quantities with the reflected beam characteristics to independently regulate each cell in the array. The simulation findings demonstrate that the suggested array structure can precisely manage the focus point's position, intensity, and scattering degree and that, with phase compensation, it can control the wide-angle incident light. The array structure offers a novel concept for adjustable devices and focusing lenses, which has excellent potential for study and application.

Synthesis and Luminescent Properties of 1,4,5-Triphenylimidazole‒Phenothiazine Fluorophores.

Two blue donor-acceptor fluorophores with 1,4,5-triphenylimidazole as the electron-transporting unit and phenothiazine as the hole-transporting unit were synthesized by grafting 1,4,5-triphenylimidazole moieties onto 3- and 3,7-position of the phenothiazine core and characterized by spectroscopic methods. Their thermal stability, photophysical, electrochemical and electroluminescence properties were systematically investigated. These compounds exhibit good thermal stability and show blue emission in dichloromethane solution and thin solid films. The solution-processed doped devices were fabricated by using these fluorophores as the emitting dopant in 1,3-bis(N-carbazolyl)benzene host, in which the device fabricated from the fluorophore containing two 1,4,5-triphenylimidazole moieties exhibited blue emission with a luminance of 648 cd/m2 and external quantum efficiency of 1.48%.

Simulation study of a temperature-calibrated double-sided polished optical fiber SPR refractive index sensor.

The temperature of the environment directly affects the accuracy of refractive index (RI) measurement. Therefore, we propose a double-sided polished surface plasmon resonance (SPR) RI fiber sensor, which is available for simultaneous measurement of the RI and temperature in real time. The proposed sensor uses single-mode fiber as a special double-sided polishing structure. The double-sided polishing regions are coated with a gold-silver hybrid film; one side is additionally coated with graphene layers to increase detection sensitivity, and the other side is coated with polydimethylsiloxane on the metal layer for temperature sensing. The simulation result shows that in the range from 1.33 to 1.35, RI sensitivity reaches as high as 2600 nm/RIU. In the range from 15°C to 85°C, temperature sensitivity reaches as high as -3.5n m/∘ C. The full width at half maximum is 65 nm. Compared with previous studies, the sensitivity is slightly improved, and an excellent temperature compensation effect can be achieved. It is suitable for high-precision measurement of the environment and biochemical aspects.

Polyacylated Anthocyanins Derived from Red Radishes Protect Vascular Endothelial Cells Against Palmitic Acid-Induced Apoptosis via the p38 MAPK Pathway.

Palmitic acid (PA), a widely consumed saturated fat, is known to induce the apoptosis of vascular endothelial cells. This study examined the protective effect of anthocyanin from red radish (ARR), which has been shown to protect the cardiovascular system and is rich in polyacylated pelargonidin (P) glycosides, on PA-treated SV 40 transfected aortic rat endothelial cells (SVAREC). In all, 22 distinct anthocyanins were identified in the ARR via ultra-high-performance liquid chromatography-triple quadrupole mass spectrometry, the most abundant of which were pelargonidin-3-(p-coumaroyl)diglucoside-5-glucoside (31.60%), pelargonidin-3-(feruloyl)diglucoside-5-(malonyl)glucoside (22.98%), pelargonidin-3-(p-coumaroyl)diglucoside-5-(malonyl)glucoside (8.02%), and pelargonidin-3-(feruloyl)diglucoside-5-glucoside (6.25%). P displayed the highest serum level (93.72%) in the ARR-treated mice, while polyacylated P glucosides were also absorbed intact. Furthermore, ARR treatment effectively increased cellular activity and reduced the ratio of Bcl-2-associated X protein : B cell lymphoma-2, while simultaneously alleviating the excessive production of reactive oxygen species in PA-treated SVAREC. Transcriptome and further verification analyses confirmed that the ARR-inhibiting PA-induced apoptosis of SVAREC was related to the p38 mitogen-activated protein kinase signaling pathway. Our results are the first to demonstrate that ARR may be a promising phytochemical in the prevention of PA-induced endothelial dysfunction.

Tunable circular dichroism based on graphene-metal split ring resonators.

The chiroptical response of the chiral metasurface can be characterized by circular dichroism, which is defined as the absorption difference between left-handed circularly polarized incidence and right-handed circularly incidence. It can be applied in biology, chemistry, optoelectronics, etc. Here, we propose a dynamically tunable chiral metasurface structure, which is composed of two metal split-ring resonators and a graphene layer embedded in dielectric. The structure reflects right-handed circularly polarized waves and absorbs left-handed circularly polarized waves under normal incidence. The overall unit structural parameters of the chiral metasurface were discussed and analyzed, and the circular dichroism was 0.85 at 1.181 THz. Additionally, the digital imaging function can be realized based on the chiral metasurface structure, and the resolution of terahertz digital imaging can be dynamically tuned by changing the Fermi level of graphene. The proposed structure has potential applications in realizing tunable dynamic imaging and other communication fields.

Dual-color meta-image display with a silver nanopolarizer based metasurface.

Plasmonic metallic nanostructures with anisotropic design have unusual polarization-selective characteristic which can be utilized to build nanopolarizers at the nanoscale. Herein, we propose a dual-color image display platform by reconfiguring two types of silver nanoblocks in a single-celled metasurface. Governed by Malus's law, the two types of silver nanoblocks both acting as nanopolarizers with different orientations can continuously modulate the intensity of incident linearly polarized red and green light pixel-by-pixel, respectively. As a result, an ultra-compact, high-resolution, and continuous-greyscale dual-color image can be recorded right at the surface of the meta-device. We demonstrate the dual-color Malus metasurface by successfully encoding and decoding a red-green continuously-grayscale image into a metasurface sample. The experimentally captured meta-image with high-fidelity and resolution as high as 63500 dots per inch (dpi) has verified our proposal. With the advantages such as continuous grayscale modulation, ultrathin, high stability and high density, the proposed dual-color encoded metasurfaces can be readily used in ultra-compact image displays, high-end anti-counterfeiting, high-density optical information storage and information encryption, etc.