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Non‐alcoholic fatty liver disease is a public health problem worldwide associated with high morbidity and hepatic steatosis, but no effective therapeutic interventions. Magnesium isoglycyrrhizinate (MGIG), a derivative of an active component of Glycyrrhiza glabra, is widely used for the treatment of inflammatory liver diseases due to its potent anti‐inflammatory and hepatoprotective activities. Hence, this study aimed to study the effects of MGIG on hepatic steatosis in mice fed a high‐fat diet (HFD). Oil Red O staining and transmission electron microscopy revealed a decrease in lipid accumulation in the liver after MGIG treatment along with improved mitochondrial ultramicrostructures. Metabonomic analysis demonstrated that MGIG intervention increased glutamate utilization in mitochondria by promoting the uptake of glutamate into the tricarboxylic acid (TCA) cycle. The NAD+/NADH ratio and the expression of other lipid‐metabolism‐related genes were increased in MGIG‐treated livers. Transcriptome sequencing showed that the expression of TLR4, an isoform of the innate immunity Toll‐like receptors (TLRs), was significantly decreased after MGIG treatment, suggesting a link between the anti‐inflammatory effects of MGIG and its suppression of lipidation. Our results reveal the potent effects of MGIG on lipid metabolism and suggest that hepatic TLR4 might be a crucial therapeutic target to regulate energy homeostasis in hepatic steatosis. [ABSTRACT FROM AUTHOR]

A thin screen exhibiting dynamically switchable transmission/absorption functionalities is highly desired in practice. However, a trilayer transmissive metasurface with active elements controlled in a uniform manner cannot exhibit independently controlled transmission and absorption properties due to intriguing interplays between the scattering and absorbing properties in systems exhibiting inversion symmetries. This motivates to employ the coupled‐mode theory to establish a generic phase diagram for such transmissive metasurfaces with active elements loaded in different layers tuned independently and to guide researchers design tunable metadevices with completely decoupled transmission/absorption responses. Based on such a phase diagram, a microwave metasurface is designed/fabricated with PIN diodes incorporated, and it is experimentally demonstrated that its functionality can switch from perfect transparency to perfect absorption, controlled by external voltages applied across the diodes. In addition to finding immediate applications in practice (e.g., smart radomes), the results of this study also provide a new type of tunable meta‐atom for building metasurfaces with flexible wave‐front control abilities. [ABSTRACT FROM AUTHOR]

With the promotion of inactivated poliomyelitis vaccine (IPV) and live attenuated oral poliomyelitis vaccine (OPV), the global reported cases of poliomyelitis have reduced sharply from 0.35 million in 1988 to 74 in 2015. The Polio Eradication & Endgame Strategic Plan published by WHO in 2013 included the strategy of implementation of poliovirus safe handling and containment measures to minimize the risks of facility-associated reintroduction of virus into the polio-free community to prevent the re-import of poliovirus. Toward this strategy, we produced replication-incompetent pseudovirus of poliovirus type 1, 2, 3 attenuated strains by constructing poliovirus capsid expression vectors and poliovirus replicon then transfecting HEK293T cells and developed a pseudovirus-based neutralization assay (pNA) to determine neutralizing antibody titer which is more secure, time-saving and reliable than conventional neutralization assay (cNA). By using anti-poliovirus rat serum, we demonstrated excellent correlation between neutralizing antibody titers measured by cNA and pNA. It was concluded that pNA can be a potential alternative to replace cNA as a safe and time-saving system for titer determination after live poliovirus's safekeeping. [ABSTRACT FROM AUTHOR]

In article number 1800081, Lei Zhou, Lin Chen, and co‐workers propose an alternative approach to realize high‐efficiency transmission‐mode metasurfaces to control electromagnetic wave‐fronts, based on hyperbolic metamaterial waveguides. An anomalous refracted beam is realized with a conversion efficiency of 42.9% in the microwave region and 77.9% in the near infrared region. This work may advance a new class of research to develop electromagnetic waves functional devices based on hyperbolic metamaterials, particularly at high frequencies, with the existing fabrication technology. [ABSTRACT FROM AUTHOR]

Metasurfaces have shown great potential to reshape the wavefront of electromagnetic (EM) waves, but transmissive meta‐devices face challenges of low‐efficiency and/or fabrication complexities. Here, an alternative approach to realize high‐efficiency transmission‐mode meta‐devices to control EM wavefronts, based on hyperbolic metamaterial (HMM) waveguides supporting tailored spoof surface plasmons (SSPs) on their side walls, is proposed. By manipulating the dispersions of SSPs through adjusting the HMM geometrical parameters, the phases of EM waves passing through such waveguides, which enables the design of meta‐devices with desired transmission‐phase profiles for particular wave‐manipulation applications, can be controlled. Microwave experiments are implemented to demonstrate two wave‐control effects based on the mechanism, that is, beam‐deflection and focusing, and a maximum conversion efficiency of 42.9% is achieved for the anomalous refracted beam. By scaling down the HMM meta‐devices, the proposal herein is applicable to optical frequencies and in principle promises significantly raised conversion efficiencies. The scheme herein can offer a higher effective refractive index and more tunable dispersion without using high‐index dielectric materials, and thus can serve as an effective and robust approach to make high‐efficiency transmissive meta‐devices with diversified functionalities. Hyperbolic metamaterial (HMM) meta‐devices are proposed to construct high‐efficiency transmissive metasurfaces for wavefront manipulation over the entire spectral regimes without the requirement of high‐index materials. HMM meta‐devices enable an anomalous refracted beam for linearly polarized and circularly polarized electromagnetic waves with conversion efficiencies of 42.9% in the microwave region and 77.9% in the near infrared region. [ABSTRACT FROM AUTHOR]