Ultra-Wideband Transformer Feedback Monolithic Microwave Integrated Circuit Power Amplifier Design on 0.25 µm GaN Process.

This paper presents an ultra-wideband transformer feedback (TFB) monolithic microwave integrated circuit (MMIC) power amplifier (PA) developed using a 0.25 µm gallium nitride (GaN) process. To broaden the bandwidth, a drain-to-gate TFB technique is employed in this PA design, achieving a 117% relative -3 dB bandwidth, extending from 5.4 GHz to 20.3 GHz. At a 28 V supply, the designed PA circuit achieves an output power of 25.5 dBm and a 14 dB small-signal gain in the frequency range of 6 to 19 GHz. Within the 6 to 19 GHz frequency range, the small-signal gain exhibits a flatness of less than 0.78 dB. The PA chip occupies an area of 1.571 mm2. This work is the first to design a power amplifier with on-chip transformer feedback in a compound semiconductor MMIC process, and it enables the use of the widest bandwidth power amplifier on-chip transformer matching network.

Polymerizable Deep Eutectic Solvent-Based Polymer Electrolyte for Advanced Dendrite-Free, High-Rate, and Long-Life Li Metal Batteries.

The recently developed advanced electrolytes possess many crucial qualities, including robust stability, Li dendrite-free, and comparable interface compatibility, for the manufacturing of Li metal batteries with a high energy density. In this study, lithium bis(trifluoromethane)sulfonimide, acrylamide, and succinonitrile were first used to design a polymerizable monomer. Then, it went through in situ thermal polymerization to attain a new solid polymer electrolyte [named poly(PDES)]. The synthesized poly(PDES) electrolyte achieved higher ionic conductivity (∼1.89 × 10-3 S cm-1), oxidation potential (∼5.10 V versus Li+/Li), and a larger lithium-ion transfer number (∼0.63). Moreover, poly(PDES) was nonflammable and could effectively inhibit the formation of Li dendrites. As a result, the assembled batteries using the poly(PDES) electrolyte for both Li||LiFePO4 and Li||LiNi0.8Co0.1Mn0.1O2 exhibited excellent interface compatibility and electrochemical performances. This poly(PDES) electrolyte has promising potential for broad application in lithium-metal batteries with elevated energy density and safety performance in the near future.

Injectable thermo-sensitive and wide-crack self-healing hydrogel loaded with antibacterial anti-inflammatory dipotassium glycyrrhizate for full-thickness skin wound repair.

Severe skin injuries are hard to repair and susceptible to bacterial infection. Development of a versatile antimicrobial anti-inflammatory hydrogel dressing that eliminates concern over antibiotic resistance is urgently needed but remains an elusive goal. Our research, described herein, the design and fabrication of a new family of supramolecular hydrogels based on hydroxypropyl chitosan (HPCS) and poly(N-isopropylacrylamide) (PNIPAM) may prove to be that goal. Employing the reversible cross-linking by ß-cyclodextrin (ß-CD) and adamantyl (AD) pre-assembly, the hydrogels can be formed in a facile one-pot method. Additionally, the structure and performance of the hydrogels can be controlled by a simple adjustment of the AD content. The obtained hydrogels exhibit an abundance of desired properties; they are injectable, thermosensitive, highly ductile, self-healable (will self-heal recurring damage to the hydrogel bandage of up to several millimeters wide), biocompatible, and have antimicrobial activity against Staphylococcus aureus when infused with dipotassium glycyrrhizinate (DG). Using a mouse full-thickness skin defect model, in vivo wound healing evaluations revealed that the DG-loaded hydrogels (HP-3/DG10) applied to the wound resulted in rapid wound closure. The hydrogels promoted efficient tissue remolding, collagen deposition, decreased inflammation and performed better than the control groups of commercial TegadermTM film and 3M dressing. Given their multifunctionality and in vivo efficacy, the DG-loaded HP hydrogels hold great potential as a wound dressing for full-thickness skin repair. STATEMENT OF SIGNIFICANCE: Injectable hydrogels are receiving increasing attention as an ideal wound dressing. To the best of our knowledge, however, injectable and wide-crack self-healing hydrogel dressings have been hardly studied. A versatile antimicrobial hydrogel without drug resistance or cytotoxicity is also highly required. Therefore, in the present study, we constructed injectable thermosensitive and wide-crack self-healing hydrogels with antibacterial and anti-inflammatory properties. These hydrogels were developed through novel strategies of the wide-crack self-healing design and the loading of the bioactive antibacterial and anti-inflammatory agent dipotassium glycyrrhizinate. The simple preparation method and multifunctionality of the studied hydrogel composites may provide important insights for the development of future biomaterials for wound dressings and other biomedical applications.

Reduced Red Mud as the Solar Absorber for Solar-Driven Water Evaporation and Vapor-Electricity Generation.

The emergent solar-driven water evaporation technology provides a reassuring scheme for red mud (RM) utilization in environment and materials science. With fewer restrictions on raw materials, wide availability of sheer quantity, and high complexity in chemical composition, the RM may be a promising candidate for solar absorbers. Here, we developed a novel solar absorber with reduced RM. It features favorable light absorption and photothermal conversion ability using biomass pyrolysis. When added to the polyvinyl alcohol and chitosan gel substrate, the light absorptance can reach 94.65%, while the corresponding evaporation rate is as high as 2.185 kg m-2 h-1 under an illumination density of 1 kW m-2. We further demonstrated its potential as an efficient solar absorber in the solar-driven water evaporation and the thermoelectric device to realize the stable and efficient coproduction of vapor and electricity.

Chemical composition of Blumea balsamifera and Magnolia sieboldii essential oils and prevention of UV-B radiation-induced skin photoaging.

Blumea balsamifera essential oils (BBEOs) and Magnolia sieboldii essential oils (MSEOs) have exhibited outstanding antioxidant, anti-bacterial and anti-inflammatory activities. However, their anti-photoaging ability is still unclear. In this study, the chemical compositions of BBEOs and MSEOs are firstly determined by GC-MS analysis, and then their anti-photoaging is evaluated via an ultraviolet radiation (UV-B) induced mice skin-injury model. A total of 35 and 33 components are identified from BBEOs and MSEOs, and their dominant compositions are caryophyllene (18.54%) and borneol (18.33%) in BBEOs, and ß-elemene (29.10%), γ-terpinene (17.01%) and (E)-ß-ocymene (11.69%) in MSEOs. According to the skin injury model, the application of BBEOs and MSEOs to mice skin can effectively inhibit skin photoaging by down-regulating the expression of inflammatory factors including TNF-α, IL-6 and IL-10. Clearly, both essential oils reveal the potential as additives in cosmetics for anti-photoaging.

lncRNA MIR4435-2HG promotes cancer cell migration and invasion in prostate carcinoma by upregulating TGF-ß1.

The long noncoding (lnc) RNA MIR4435-2HG is known to promote lung cancer; however, its role in prostate carcinoma (PCa) remains unknown. The aim of the current study was therefore to investigate the role of MIR4435-2HG in PCa by detecting differential gene expression using quantitative PCR and ELISA kits. Furthermore, overexpression experiments were performed to analyze gene interactions and Transwell assays were used to analyze cell invasion and migration. The present study demonstrated that plasma levels of MIR4435-2HG and transforming growth factor-ß1 (TGF-ß1) were significantly higher in patients with PCa compared with healthy controls. Furthermore, MIR4435-2HG and TGF-ß1 plasma levels were positively correlated in patients with PCa, but not in healthy controls. The results from the follow-up study suggested that MIR4435-2HG was closely associated with patient survival. MIR4435-2HG overexpression and treatment with TGF-ß1 promoted cancer cell invasion and migration. In addition, TGF-ß inhibitor attenuated the enhancing effects of MIR4435-2HG overexpression on cell invasion and migration. MIR4435-2HG overexpression led to upregulation of TGF-ß1 expression, whereas TGF-ß1 treatment had no effect on MIR4435-2HG expression. These results suggested that MIR4435-2HG may promote PCa by upregulating TGF-ß1.

Secure thermal infrared communications using engineered blackbody radiation.

The thermal (emitted) infrared frequency bands, from 20-40 THz and 60-100 THz, are best known for applications in thermography. This underused and unregulated part of the spectral range offers opportunities for the development of secure communications. The 'THz Torch' concept was recently presented by the authors. This technology fundamentally exploits engineered blackbody radiation, by partitioning thermally-generated spectral noise power into pre-defined frequency channels; the energy in each channel is then independently pulsed modulated and multiplexing schemes are introduced to create a robust form of short-range secure communications in the far/mid infrared. To date, octave bandwidth (25-50 THz) single-channel links have been demonstrated with 380 bps speeds. Multi-channel 'THz Torch' frequency division multiplexing (FDM) and frequency-hopping spread-spectrum (FHSS) schemes have been proposed, but only a slow 40 bps FDM scheme has been demonstrated experimentally. Here, we report a much faster 1,280 bps FDM implementation. In addition, an experimental proof-of-concept FHSS scheme is demonstrated for the first time, having a 320 bps data rate. With both 4-channel multiplexing schemes, measured bit error rates (BERs) of < 10(-6) are achieved over a distance of 2.5 cm. Our approach represents a new paradigm in the way niche secure communications can be established over short links.