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In this study, we proposed a bifunctional sensor of high sensitivity and slow light based on carbon nanotubes (CNTs). An array of left semicircular ring (LSR), right semicircular ring (RSR), and circular ring (CR) resonators are utilized to form the proposed metamaterial. The proposed structure can achieve double plasmon-induced transparency (PIT) effects under the excitation of a TM-polarization wave. The double PIT originated from the destructive interference between two bright modes and a dark mode. A coupled harmonic oscillator model is used to describe the destructive interference between the two bright modes and a dark mode, and the simulation results agree well with the calculated results. Moreover, we investigate the influence of the coupling distance, period, and flare angle on the PIT spectra. The relationship between the resonant frequencies, full width at half maximum (FWHM), amplitudes, quality factors (Q), and the coupling distance is also studied. Finally, a high sensitivity of 1.02 THz RIU−1 is obtained, and the transmission performance can be maintained at a good level when the incident angle is less than 40°. Thus, the sensor can cope with situations where electromagnetic waves are not perpendicular to the structure's surface. The maximum figure of merit (FOM) can reach about 8.26 RIU−1; to verify the slow light property of the device, the slow light performance of the proposed structure is investigated, and a maximum time delay (TD) of 22.26 ps is obtained. The proposed CNT-based metamaterial can be used in electromagnetically induced transparency applications, such as sensors, optical memory devices, and flexible terahertz functional devices. [ABSTRACT FROM AUTHOR]

Alcoholic hepatitis (AH) continues to be a disease with high mortality and no efficacious medical treatment. Although severe AH is presented as acute on chronic liver failure, what underlies this transition from chronic alcoholic steatohepatitis (ASH) to AH is largely unknown. To address this question, unbiased RNA sequencing and proteomic analyses were performed on livers of the recently developed AH mouse model, which exhibits the shift to AH from chronic ASH upon weekly alcohol binge, and these results are compared to gene expression profiling data from AH patients. This cross-analysis has identified Casp11 (CASP4 in humans) as a commonly up-regulated gene known to be involved in the noncanonical inflammasome pathway. Immunoblotting confirms CASP11/4 activation in AH mice and patients, but not in chronic ASH mice and healthy human livers. Gasdermin-D (GSDMD), which induces pyroptosis (lytic cell death caused by bacterial infection) downstream of CASP11/4 activation, is also activated in AH livers in mice and patients. CASP11 deficiency reduces GSDMD activation, bacterial load in the liver, and severity of AH in the mouse model. Conversely, the deficiency of interleukin-18, the key antimicrobial cytokine, aggravates hepatic bacterial load, GSDMD activation, and AH. Furthermore, hepatocyte-specific expression of constitutively active GSDMD worsens hepatocellular lytic death and polymorphonuclear leukocyte inflammation.ConclusionThese results implicate pyroptosis induced by the CASP11/4-GSDMD pathway in the pathogenesis of AH. (Hepatology 2018;67:1737-1753).

In this paper, we proposed an ultra-broadband and high absorption rate absorber based on Fe materials. The proposed absorber consists of a rectangle pillar, two rings, a SiO2 film, a Ge2Sb2Te5(GST) planar cavity, an Fe mirror, and a SiO2 substrate. The average absorption reaches 98.45% in the range of 400–4597 nm. We investigate and analyze the electric field distributions. The analysis of the physical mechanism behind the broadband absorption effect reveals that it is driven by excited surface plasmons. Furthermore, the absorber can maintain high absorption efficiency under a large incident angle. The geometrical symmetric structure possesses polarization insensitivity properties. The proposed structure allows for certain manufacturing errors, which improves the feasibility of the actual manufacture. Then, we investigate the effect of different materials on absorption. Finally, we study the matching degree between the energy absorption spectrum and the standard solar spectrum under AM 1.5. The results reveal that the energy absorption spectrum matches well with the standard solar spectrum under AM 1.5 over the full range of 400 to 6000 nm. In contrast, energy loss can be negligible. The absorber possesses ultra-broadband perfect absorption, a high absorption rate, and a simple structure which is easy to manufacture. It has tremendous application potential in many areas, such as solar energy capture, thermal photovoltaics, terminal imaging, and other optoelectronic devices. [ABSTRACT FROM AUTHOR]

In this paper, a TM polarization multi-band absorber is achieved in a graphene–Ag asymmetrical grating structure. The proposed absorber can achieve perfect absorption at 1108 nm, 1254 nm, and 1712 nm (the absorption exceeds 98.4% at the three peaks). Results show that the perfect absorption effect originates from the excitation of magnetic polaritons (MPs) in the silver ridge grating; a LC equivalent circuit model is utilized to confirm the finite-difference-time-domain (FDTD) simulation. The influences of the incident angle, polarization angle, and geometrical size on the absorption spectrum are investigated. Moreover, a quadruple band absorber and a quintuple band absorber are also designed by introducing more silver grating ridges in one period. The proposed graphene–Ag asymmetrical structure has some advantages compared with other absorbers such as the ability to be independently tuned and a simple structure. Thus, the proposed structure can be applied in the areas of multiple absorption switches, near-infrared modulators, and sensors. [ABSTRACT FROM AUTHOR]