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This review introduces and discusses the recent progress in high temperature microwave absorbing materials, including their loss mechanisms, preparation methods, structures and electromagnetic properties.

Many microorganisms have mechanisms that protect cells against attack from viruses. The fermentation components of Streptomyces sp. 1647 exhibit potent anti-influenza A virus (IAV) activity. This strain was isolated from soil in southern China in the 1970s, but the chemical nature of its antiviral substance(s) has remained unknown until now. We used an integrated multi-omics strategy to identify the antiviral agents from this streptomycete. The antibiotics and Secondary Metabolite Analysis Shell (antiSMASH) analysis of its genome sequence revealed 38 biosynthetic gene clusters (BGCs) for secondary metabolites, and the target BGCs possibly responsible for the production of antiviral components were narrowed down to three BGCs by bioactivity-guided comparative transcriptomics analysis. Through bioinformatics analysis and genetic manipulation of the regulators and a biosynthetic gene, cluster 36 was identified as the BGC responsible for the biosynthesis of the antiviral compounds. Bioactivity-based molecular networking analysis of mass spectrometric data from different recombinant strains illustrated that the antiviral compounds were a class of structural analogues. Finally, 18 pseudo-tetrapeptides with an internal ureido linkage, omicsynins A1–A6, B1–B6, and C1–C6, were identified and/or isolated from fermentation broth. Among them, 11 compounds (omicsynins A1, A2, A6, B1–B3, B5, B6, C1, C2, and C6) are new compounds. Omicsynins B1–B4 exhibited potent antiviral activity against IAV with the 50% inhibitory concentration (IC50) of approximately 1 µmol∙L–1 and a selectivity index (SI) ranging from 100 to 300. Omicsynins B1–B4 also showed significant antiviral activity against human coronavirus HCoV-229E. By integrating multi-omics data, we discovered a number of novel antiviral pseudo-tetrapeptides produced by Streptomyces sp. 1647, indicating that the secondary metabolites of microorganisms are a valuable source of novel antivirals.

In this paper, to provide references for coordinating the development of digital inclusive finance between provinces and regions in China, we measure the digital financial inclusion index of 31 provinces in China from 2011 to 2020 based on three dimensions: coverage breadth, depth of use and digitalization degree. By means of the weighted Dagum Gini coefficient and quantile standardization, we explored the degree of imbalance and insufficiency of the development of digital inclusive finance in China and four major regions and its structural causes. Using the Kernel density estimation method and Markov chain analysis method, we further investigate the evolution trend of imbalance and insufficiency. The study finds that (1) the Digital Inclusive Financial Index in China and the four major regions rose significantly, with the COVID-19 epidemic reducing its growth rate. Of these, the eastern region has the highest development level. (2) The imbalance level of digital inclusive finance development obviously has reduced. The level of imbalance is highest within the eastern region, and the development gap between the eastern and western regions is the widest. The imbalance of overall development is mainly due to regional imbalance. The imbalance of coverage breadth and depth of use is the main structural cause of unbalanced development in the four major regions. There is a trend of bipolarization or multipolarization in China and the other three major regions, with the exception of the central region. (3) The western region is the least developed. The development shortcoming of digital inclusive finance in China and the four major regions is the breadth of coverage. There are the “Club Convergence” and the “Matthew Effect” in the eastern, central and western regions.

In the paper, we measure the digital financial inclusion index of 31 provinces in China from 2011 to 2020 based on three dimensions: coverage breadth, depth of use and digitalization degree. By means of weighted Dagum Gini coefficient and quantile standardization, we explored the degree of imbalance and insufficiency of the development of digital inclusive finance in China and four major regions and its structural causes. Using Kernel density estimation method and Markov chain analysis method, we further investigates the evolution trend of imbalance and insufficiency. The study finds that (1) the Digital Inclusive Financial Index in China and the four major regions rise significantly, with the COVID-19 epidemic reducing its growth rate. Of these, the eastern region has the highest development level. (2) The imbalance level of digital inclusive finance development obviously has reduced. The level of imbalance is highest within the eastern region, and the development gap between the eastern and western regions is the widest. The imbalance of overall development is mainly due to the regional imbalance. The imbalance of coverage breadth and depth of use is the main structural cause of unbalanced development in the four major regions. There is a trend of bipolarization or multipolarization in China and the other three major regions, with the exception of the central region. (3) The western region is the least developed. The development shortcoming of digital inclusive finance in China and the four major regions is the breadth of coverage. There are "Club Convergence" and "Matthew Effect" in the eastern, central and western regions.

Gel polymer-ceramic hybrid electrolytes (GHEs) have emerged as desirable candidates for preparing high energy density and excellent practicability gel batteries. However, the agglomeration of ceramic particles in polymer matrix leads to a decrease in cycling stability and low mechanical properties of GHEs. Here, we present a feasible method for improving the dispersity of Li0.24La0.59TiO3 (LLTO) nanorods in the polyvinylidenefluoride (PVDF)/poly(propylene carbonate) (PPC) co-blended matrix (K–LLTO/PVDF/PPC) by γ-(2,3-epoxypropoxy)propytrimethoxysilane (KH560) surface treatment. The as-prepared GHE with 10% K–LLTO filler (10% GHE) exhibits a high ionic conductivity (3.01 mS cm−1) and an appropriate lithium-ion transference number (0.55). The Li|10% GHE|Li symmetric cell shows an exceptional lithium stripping-plating lifetime of > 2000 h at 0.1 mA cm−2. The assembled LiFePO4 (LFP)|10% GHE|Li full cells show satisfactory cycling stability in the 2.5–4.2 V electrochemical window by recovering 84% of the initial capacity at 2 C over 500 cycles. The uniformly dispersed K–LLTO within the polymer matrix is ascribed to the formation of a bridge-linked network via Si–O–Ti bonds between KH560 and LLTO, and plenty of hydrogen bonds within the polymer matrix. This modification method provides a feasible strategy for fabricating GHEs with good repeatability, which may easily adapt to the high requirements of commercial production.

N-doping and phase regulation of MoS2via room temperature NH3 plasma technology achieve efficient bidirectional catalysis for lithium–sulfur electrochemistry.

The synergistic effect between crystal structure and cathodic doping is proposed to enhance the specific capacitance of WN by about 9 times.

A hybrid integrated gain-switched (GS) optical frequency comb (OFC) source with eight pure continuous comb lines within 3-dB of the spectral envelope peak and a narrow linewidth of 615 kHz is proposed and demonstrated by coupling a silicon nitride microring reflector (MRR) to a commercially available distributed feedback (DFB) laser. Due to the self-injection locking effect induced by the MRR, the carrier-to-noise ratio (CNR) and phase correlation between comb lines are greatly enhanced. In addition, benefiting from the unique merit of gain switching, the resultant comb can also achieve a large frequency spacing adjustment range from 5.55 GHz to 8.7 GHz. This work explores a cost-efficient and robust OFC source for numerous applications, such as radio over fiber (RoF) and coherent optical communication.

Exploring highly foldable batteries with no safety hazard is a crucial task for the realization of portable, wearable, and implantable electric devices. Given these concerns, developing solid-state batteries is one of the most promising routes to achieve this aspiration. Because of the excellent flexibility and processability, polyvinylidene fluoride (PVDF) based electrolytes possess great potential to pack high energy density flexible batteries, however, suffers the various intrinsic shortcomings such as inferior ionic conductivity, a high degree of crystallinity, and lack of reactive groups. Clearing the progress of the present state and concluding the specific challenges faced by PVDF based electrolytes will help to develop PVDF based polymer batteries. In this review, we summarize the recent progress of gel polymer electrolytes and all solid polymer electrolytes based on PVDF. The ion transport mechanisms and preparation methods of PVDF based electrolytes are briefly introduced. Meanwhile, the current design principle and properties of electrolytes are highlighted and systematically discussed. Some peculiar modified strategies performed in lithium–sulfur batteries and lithium–oxygen batteries are also included. Finally, this review describes the challenges and prospects of some solid-state electrolytes to provide strategies for manufacturing high-performance PVDF electrolytes aimed at practical application with flexible requirements.

Pancreatic adenocarcinoma (PAAD) is one of the most lethal malignancies. Although gemcitabine (GEM) is a standard treatment for PAAD, resistance limits its application and therapy. Secoemestrin C (Sec C) is a natural compound from the endophytic fungus Emericella, and its anticancer activity has not been investigated since it was isolated. Our research is the first to indicate that Sec C is a broad-spectrum anticancer agent and could exhibit potently similar anticancer activity both in GEM-resistant and GEM-sensitive PAAD cells. Interestingly, Sec C exerted a rapid growth-inhibiting effect (80% death at 6 h), which might be beneficial for patients who need rapid tumor shrinkage before surgery. Liquid chromatography/mass spectrometry and N-acetyl- l -cysteine (NAC) reverse assays show that Sec C sulfates cysteines to disrupt disulfide-bonds formation in endoplasmic reticulum (ER) proteins to cause protein misfolding, leading to ER stress and disorder of lipid biosynthesis. Microarray data and subsequent assays show that ER stress-mediated ER-associated degradation (ERAD) ubiquitinates and downregulates YAP to enhance ER stress via destruction complex (YAP–Axin–GSK–βTrCP), which also elucidates a unique degrading style for YAP. Potent anticancer activity in GEM-resistant cells and low toxicity make Sec C a promising anti-PAAD candidate.

Background: Previous studies have suggested that dexmedetomidine may have a protective effect on renal function. However, it is currently unclear whether perioperative dexmedetomidine administration is associated with postoperative acute kidney injury (AKI) incidence risk in hypertensive patients undergoing non-cardiac surgery.Methods: This investigation was a retrospective cohort study. Hypertensive patients undergoing non-cardiac surgery in Third Xiangya Hospital of Central South University from June 2018 to December 2019 were included. The relevant data were extracted through electronic cases. The univariable analysis identified demographic, preoperative laboratory, and intraoperative factors associated with acute kidney injury. Multivariable stepwise logistic regression was used to assess the association between perioperative dexmedetomidine administration and postoperative acute kidney injury after adjusting for interference factors. In addition, we further performed sensitivity analyses in four subgroups to further validate the robustness of the results.Results: A total of 5769 patients were included in this study, with a 7.66% incidence of postoperative acute kidney injury. The incidence of postoperative acute kidney injury was lower in the dexmedetomidine-administered group than in the control group (4.12% vs. 8.06%, p < 0.001). In the multivariable stepwise logistic regression analysis, perioperative dexmedetomidine administration significantly reduced the risk of postoperative acute kidney injury after adjusting for interference factors [odds ratio (OR) = 0.56, 95% confidence interval (CI): 0.36–0.87, p = 0.010]. In addition, sensitivity analysis in four subgroups indicated parallel findings: i) eGRF 2 subgroup (OR = 0.40, 95% CI: 0.19–0.84, p = 0.016), ii) intraoperative blood loss p = 0.025), iii) non-diabetes subgroup (OR = 0.51, 95% CI: 0.29–0.89, p = 0.018), and iv) older subgroup (OR = 0.55, 95% CI: 0.32–0.93, p = 0.027).Conclusion: In conclusion, our study suggests that perioperative dexmedetomidine administration is associated with lower risk and less severity of postoperative acute kidney injury in hypertensive individuals undergoing non-cardiac surgery. Therefore, future large-scale RCT studies are necessary to validate this benefit.

Three new hexadepsipeptides (1–3), along with beauvericin (4), beauvericin D (5), and four 4-hydroxy-2-pyridone derivatives (6–9) were isolated from the endophytic fungus Fusarium sp. CPCC 400857 that derived from the stem of tea plant. Their structures were determined by extensive 1D and 2D NMR, and HRESIMS analyses. The absolute configuration of hexadepsipeptides were elucidated by the advanced Marfey’s method and chiral HPLC analysis. Compounds 4, and 7–9 displayed the cytotoxicity against human pancreatic cancer cell line, AsPC-1 with IC50 values ranging from 3.45 to 29.69 μM, and 7 and 8 also showed the antiviral activity against the coronavirus (HCoV-OC43) with IC50 values of 13.33 and 6.65 μM, respectively.

Zinc-ion batteries (ZIBs) with near-neutral aqueous electrolytes are considered as competitive systems for large-scale energy storage and wearable electronics applications due to their low cost, high security, desirable specific capacity, and environmental friendliness. However, the sluggish electrode reaction kinetics, poor structural stability, severe Zn dendrite growth, and narrow electrochemical stability window in the entire cell still impede the realization of their full potentials. To address these intrinsic issues in aqueous ZIBs, tremendous efforts have been devoted to boosting their electrochemical properties, such as cycling performance, specific capacity, rate capability, and operating voltage. In this review, we start with the discussion of electrode materials and energy storage mechanisms in aqueous ZIBs. Then specific attention is concentrated on the key issues and recent advances in design strategies for optimizing electrochemical performance in aqueous ZIBs systems. Finally, some potential challenges and future research directions to meet practical applications are also provided.

The endophytic fungus Diaporthe sp. is known to contain many secondary metabolites, but fatty acid derivatives have rarely been found. In this study, four new fatty acid derivatives (1–4), together with four known compounds (5–8), were isolated from Diaporthe sp., which was obtained from the stem of Ligularia fischeri. The absolute configurations of the new compounds 1–4 were deduced based on spectroscopic technique and J-based coupling constant analysis. Moreover, compound 1 exhibited cytotoxic activities against HCT-8 and MCF-7 cancer cells, and compounds 3 and 4 showed modest selectivity for HCT-8 cells by MTT assay.

Krüppel-like factor 2 (KLF2) is an atherosclerotic protective transcription factor that maintains endothelial cell homeostasis through its anti-inflammatory, anti-oxidant, and antithrombotic properties. The aim of this study was to discover KLF2 activators from microbial secondary metabolites and explore their potential molecular mechanisms. By using a high-throughput screening model based on a KLF2 promoter luciferase reporter assay, column chromatography, electrospray ionization mass spectrometry (ESI-MS), and nuclear magnetic resonance (NMR) spectra, trichostatin D (TSD) was isolated from the rice fermentation of Streptomyces sp. CPCC203909 and identified as a novel KLF2 activator. Real-time-quantitative polymerase chain reaction (RT-qPCR) results showed that TSD upregulated the mRNA level of KLF2 in endothelial cells. Functional assays showed that TSD attenuated monocyte adhesion to endothelial cells, decreased vascular cell adhesion protein 1 (VCAM-1) and intercellular adhesion molecule 1 (ICAM-1) expression, and exhibited an anti-inflammatory effect in tumor necrosis factor alpha (TNFα)-induced endothelial cells. We further demonstrated through siRNA and western blot assays that the effects of TSD on monocyte adhesion and inflammation in endothelial cells were partly dependent on upregulating KLF2 expression and then inhibiting the NOD-like receptor protein 3 (NLRP3)/Caspase-1/interleukin-1beta (IL-1β) signaling pathway. Furthermore, histone deacetylase (HDAC) overexpression and molecular docking analysis results showed that TSD upregulated KLF2 expression by inhibiting HDAC 4, 5, and 7 activities. Taken together, TSD was isolated from the fermentation of Streptomyces sp. CPCC203909 and first reported as a potential activator of KLF2 in this study. Furthermore, TSD upregulated KLF2 expression by inhibiting HDAC 4, 5, and 7 and attenuated endothelial inflammation via regulation of the KLF2/NLRP3/Caspase-1/IL-1β signaling pathway.

Narrow linewidth and fast-chirped frequency are essential in frequency-modulated continuous-wave lasers. We introduce a laser that meets these requirements by coupling a distributed feedback laser with an external high-Q microring resonator, where a bulky stacked piezoelectric chip is attached to the resonator for fast tuning. The laser demonstrates an ultranarrow intrinsic linewidth of 22 Hz in the self-injection-locked state. Actuated by the bulky piezoelectric chip, the maximum triangular actuation bandwidth can reach 100 kHz. The driving voltage is filtered to avoid a resonant mechanical mode, obtaining the minimum residual linearity error at 10 kHz with a 4.2 GHz tuning range. A light detection and ranging system was set up for a proof-of-concept experiment, demonstrating a high detection precision with standard deviations of 2.7 and 4.0 cm for targets at 15 and 30 m, respectively.