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We prove a reversed Hardy–Littlewood–Pólya inequality with finite terms. We also give the limit of the best constant.

The three transition metal atoms in the ground state structures of Ni2TiO2(CO)2–4− form a quasi-line. The extra electron is enriched on O attached to Ti. There has strong interaction between Ti and O.

Herein, we theoretically demonstrate that a double-layer symmetric gratings (DLSG) resonator consisting of a low-refractive-index layer sandwiched between two high-contrast gratings (HCG) layers, can host dual-band high-quality (Q) factor resonance. We find that the artificial bound states in the continuum (BIC) and Fabry–Pérot BIC (FP-BIC) can be induced by optimizing structural parameters of DLSG. Interestingly, the artificial BIC is governed by the spacing between the two rectangular dielectric gratings, while the FP-BIC is achieved by controlling the cavity length of the structure. Further, the two types of BIC can be converted into quasi-BIC (QBIC) by either changing the spacing between adjacent gratings or changing the distance between the upper and lower gratings. The simulation results show that the dual-band high-performance sensor is achieved with the highest sensitivity of 453 nm/RIU and a maximum figure of merit (FOM) of 9808. Such dual-band high-Q resonator is expected to have promising applications in multi-wavelength sensing and nonlinear optics.

In order to analyze the current situation and cutting-edge trends of interface design research in Chinese and international academia, as well as the respective research characteristics and paradigm differences between Chinese and foreign academia. VOSviewer and CiteSpace metrological visualization software were integrated to visualize and analyze the literature related to interface design research included in CNKI and Web of Science databases in terms of keyword co-occurrence, keyword clustering , keyword highlighting and highly cited literature by drawing knowledge maps. The results of the study show that the Chinese academic research on interface design focuses on the topics of graphical user interface, human-computer interaction, user experience, and usability, while the international academic research focuses on usability evaluation, intelligent user interface, adaptive user interface and augmented reality, etc. In terms of future research trends, the Chinese academic community focuses on user experience, eye tracking, visual design and other directions, while the international academic community starts to explore the direction of natural interaction from physical interaction, focusing on user experience, gesture recognition, natural user interface and other directions. In terms of research paradigms, the differences between Chinese and international academics are more significant, Chinese academics focus on qualitative research, while international academics focus on quantitative empirical research.

In a recent study, Sun et al. (AOR 292:113–131, 2020) studied due-window proportionate flow shop scheduling problems with position-dependent weights. For common due-window (denoted by CONW) and slack due-window (denoted by SLKW) assignment methods, they proved that these two problems can be solved in $$O(n^2\log n)$$ time respectively, where n is the number of jobs. In this paper, we consider the same problems, and our contribution is that the CONW problem can be optimally solved by a lower-order algorithm, which runs in $$O(n\log n)$$ time, implying an improvement of a factor of n.

This paper considers the single machine scheduling problem with three different due dates in which the actual processing time of the job is a simple deterioration function of the starting time. The goal is to minimize the total costs that contain the earliness, tardiness and due date. We prove that these problems are polynomial time solvable, and we propose the corresponding algorithms to obtain the optimal sequence and due date.

The CO2 activation by transition metals is important in CO2 utilization but has proven to be challenging for experimental targets. Here we report first synthesis and spectroscopic characterization of transition-metal M[η2-(O,O)C] species with bidentate double oxygen metal-CO2 coordination in the [ZrO(CO2)n≥4]+ complexes. The Zr[η2-(O,O)C] species yields a CO2- radical ligand, showing a high efficiency in CO2 activation. We find that two important prerequisites are demanded for certain metals to form this intriguing M[η2-(O,O)C] species. One is that the metal center has high reduction capability, and the other is that the oxidation state of the metal center is lower than its highest one by 1. This study highlights the pivotal roles played by the M[η2-(O,O)C] species in CO2 activation and also open new avenues toward the development of related single-atom catalysts with isolated transition-metal atoms dispersed on supports.

Herein, amino-functionalized multilayer titanium carbide (NH

Electron adsorption ionization ion mobility spectrometry can be used to detect halogen-containing volatile organic compounds with high sensitivity. However, this traditional electron attachment detection method cannot distinguish between volatile organic compounds containing the same halogen. For different organic compounds containing the same halogen, the product ions formed by the dissociation electron attachment process are the same. In this article, we propose a novel negative corona discharge ion mobility spectrometry method to distinguish between and detect halogenated alkanes containing the same halogen according to the different electron attachment rates and reaction kinetic parameters of the different halogenated alkanes. Although these halogenated alkanes, which contain the same halogen, produce the same type of ions through the electron attachment process, their electron attachment rates are different from each other. In this work, the kinetic information is used as the fingerprint information for the tested samples to distinguish different halogenated alkanes. Five halogenated alkanes were successfully detected using this method. The results show that the method based on the electron attachment rate constant is feasible for the determination of halogenated alkanes containing the same halogen.

Background Inonotus obliquus is an important edible and medicinal mushroom that was shown to have many pharmacological activities in preclinical trials, including anti-inflammatory, antitumor, immunomodulatory, and antioxidant effects. However, the biosynthesis of these pharmacological components has rarely been reported. The lack of genomic information has hindered further molecular characterization of this mushroom. Results In this study, we report the genome of I. obliquus using a combined high-throughput Illumina NovaSeq with Oxford Nanopore PromethION sequencing platform. The de novo assembled 38.18 Mb I. obliquus genome was determined to harbor 12,525 predicted protein-coding genes, with 81.83% of them having detectable sequence similarities to others available in public databases. Phylogenetic analysis revealed the close evolutionary relationship of I. obliquus with Fomitiporia mediterranea and Sanghuangporus baumii in the Hymenochaetales clade. According to the distribution of reproduction-related genes, we predict that this mushroom possesses a tetrapolar heterothallic reproductive system. The I. obliquus genome was found to encode a repertoire of enzymes involved in carbohydrate metabolism, along with 135 cytochrome P450 proteins. The genome annotation revealed genes encoding key enzymes responsible for secondary metabolite biosynthesis, such as polysaccharides, polyketides, and terpenoids. Among them, we found four polyketide synthases and 20 sesquiterpenoid synthases belonging to four more types of cyclization mechanism, as well as 13 putative biosynthesis gene clusters involved in terpenoid synthesis in I. obliquus. Conclusions To the best of our knowledge, this is the first reported genome of I. obliquus; we discussed its genome characteristics and functional annotations in detail and predicted secondary metabolic biosynthesis-related genes, which provides genomic information for future studies on its associated molecular mechanism.

We proposed a high-performance integrated optical sensor based on a stacked resonant compound grating (SRCG). The transmission spectrum of a SRCG is investigated by the theoretical model that combines the coupled mode theory with the eigenmode information of the grating structures. It is found that the spectral width of the SRCG is controlled by changing its structural parameters such as the strip depth, the period of the grating, and cavity length. The simulation results, which are verified by finite element method (FEM), show that the sensitivity of the sensor is 401.8 nm/RIU with its figure of merit (FOM) as high as 57404. The presented sensor is a promising application for high-performance biosensing.

Veronicastrum latifolium (V. latifolium) is rich in biologically active flavonoids, and is widely used in folk medicine. The purpose of this study was to investigate flavonoids of V. latifolium, and evaluate its antioxidant, antimicrobial, and anti-inflammatory activities. Eight flavonoids including vitexin, luteolin, wogonoside, apigenin, hispidulin, chrysoeriol, acacetin, and pectolinarigenin were identified by LC–MS/MS. The purified extract was obtained by enriching crude extract of V. latifolium through macroporous adsorption resins (MARs). The antioxidant activity of the crude extract and purified extract was evaluated by (1,1-diphenyl-2-picrylhydrazyl) DPPH, (Ferric ion reducing antioxidant power) FRAP, and (2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)) ABTS assay. This study found that the crude extract and purified extract exhibited ability to scavenge free radicals, and the ability of the purified extract to scavenge free radicals was stronger than the crude extract in DPPH, ABTS, and FRAP assay. In addition, the antimicrobial activity of the crude extract and purified extract against five bacterial strains (Staphylococcus aureus (S. aureus), Bacillus subtilis (B. subtilis), Escherichia coli (E. coli), Pseudomonas aeruginosa (P. aeruginosa), and Acinetobacter baumannii (A. baumannii)), and yeast (Candida albicans (C. albicans)) was investigated. The crude extract and purified extract displayed bacteriostatic effects against both gram-positive bacteria and yeast, and the bacteriostatic effects of the purified extract was stronger compared with the crude extract. The vitro cytotoxicity of the crude extract and purified extract against isolated rat peritoneal macrophages (RAW264.7) cells was considered that it was not toxic to RAW264.7 cells at the concentration of 25–300 μg/mL. Anti-inflammatory activity of the crude extract and purified extract was evaluated by their effects on nitric oxide (NO) production in lipopolysaccharide (LPS) induced RAW264.7 cells. The crude extract and purified extract significantly inhibited NO production in RAW264.7 cells at the concentration of 200 μg/mL and 300 μg/mL. This study indicated that V. latifolium has good antioxidant, antimicrobial, and anti-inflammatory effect.

A structure with new meta-atom is proposed. The meta-atom with C3 rotational symmetry consists of three slits. The slits are drilled in the metal. Based on this meta-atom, metasurface lenses with different functions are designed. It is based on the phase and amplitude modulation by tuning the rotational angle of the meta-atom. The rotational angle of each meta-atom is achieved by simulated annealing algorithm. Three kinds of focal lenses, which can realize one or two focus points on the left and right sides, have been designed in terahertz frequency. The finite-difference time-domain method is employed to verify and appraise the properties of the designed lenses. Simulation results show that the designed lenses can perform the preset functions well. It demonstrates that such meta-atom is more suitable for focusing metasurface in different directions. It will promote the lightness, miniaturization and integration of optical components. And it is more suitable for microwave and terahertz wavefront modulation.

The CO

The utilization of solar energy to drive energy conversion and simultaneously realize pollutant degradation via photocatalysis is one of most promising strategies to resolve the global energy and environment issues. During the past decade, graphite carbon nitride (g-C3N4) has attracted dramatically growing attention for solar energy conversion due to its excellent physicochemical properties as a photocatalyst. However, its practical application is still impeded by several limitations and shortcomings, such as high recombination rate of charge carriers, low visible-light absorption, etc. As an effective solution, the electronic structure tuning of g-C3N4 has been widely adopted. In this context, firstly, the paper critically focuses on the different strategies of electronic structure tuning of g-C3N4 like vacancy modification, doping, crystallinity modulation and synthesis of a new molecular structure. And the recent progress is reviewed. Finally, the challenges and future trends are summarized.

Background As one of the most common gynaecological malignant tumors, cervical cancer (CC) has become an important public health issue. Emerging evidence has revealed long non-coding RNAs (lncRNAs) are crucial regulators of biological functions in cancers, including CC. And the oncogenic role of LINC00441 has been verified in hepatocellular carcinoma (HCC). But the molecular mechanism and biological functions of LINC00441 in CC remain unknown. Methods qRT-PCR analysis detected the expression of genes in CC tissues or cells. CCK-8, colony formation, flow cytometry, transwell, western blot assays as well as animal studies were conducted to analyze the function of LINC00441 in CC. Luciferase reporter, RIP and RNA pull down assays were applied to verify the binding relations among the indicated genes. Results LINC00441 was upregulated in CC tissues and cells. Further, LINC00441 depletion repressed cell proliferation and motility in vitro as well as tumor growth in vivo. LINC00441 could sponge miR-450b-5p to upregulate RAB10 expression. Finally, miR-450b-5p inhibitor or RAB10 upregulation counteracted LINC00441 knockdown-mediated function on the development of CC. Conclusions LINC00441 drives CC progression by targeting miR-450b-5p/RAB10 axis, which might provide new idea for researching CC-related molecular mechanism.

A high performance optical sensor based on a double compound symmetric gratings (DCSGs) structure is designed. The reflection spectrum of the DCSG is investigated by utilizing a method that combines a theoretical model with the eigenmode information of the grating structure. The theoretical results, which are observed to agree well with those acquired by rigorous coupled-wave analysis, show that the linewidth of the reflection spectrum decreases upon the increasing distance between the grating strips. This research work will lay a foundation for studying high performance integrated optical sensors in miniature nanostructures.

A tunable broadband terahertz (THz) absorber based on vanadium dioxide (VO2) is proposed, which is composed of a structured VO2 metamaterial layer, a dielectric layer, and a metal layer. The simulation results show that the peak absorption intensity of the absorber can be dynamically adjusted from 3.6% to 100% by changing the conductivity of VO2. When the conductivity of VO2 is 2×105 S/m, an excellent broadband absorption phenomenon appears, and the bandwidth of absorption rate greater than 90% is as wide as 4.10 THz from 3.25 THz to 7.35 THz. The impedance matching theory and the electric field distribution are used to explain the physical mechanism of the proposed absorber. In addition, the absorber shows the advantages of polarization-insensitiveness and wide-angle absorption. It is expected that this absorber can have potential applications such as modulators and photoelectric switches.

The objective of this study is to test a mediation model in which safety motivation and self-efficacy mediate the relationship between perfectionism and situational judgment in Chinese civil flying cadets. We collected self-reported data from 218 civil flying cadets from Civil Aviation Flight University of China. The results show that concern over mistakes and personal standards have direct effects on flying cadets' situational judgment. Concern over mistakes, parental expectation and organization have indirect effects on flying cadets’ situational judgment through safety motivation; whereas concern over mistakes and parental criticism have indirect effects through self-efficacy. Managerial implications of the study as well as the future research directions are discussed.

Background/Aims: Huangqi Decoction (HQD) has been traditionally used to treat diabetes mellitus in China. The present study was carried out to assess the protective effect of HQD on diabetic nephropathy (DN) using the streptozotocin-induced (STZ) diabetic rats. Methods: Diabetes was induced by a single intraperitoneal injection of STZ (60 mg/kg) in male Wistar rats. 40 diabetic rats were divided into 5 groups: vehicle-treated (DN group), 0.45, 0.15, 0.05 g/kg HQD-treated diabetic group (HQD group) and 1 mg/kg rosiglitazone-treated diabetic group (RGZ group). 16 normal rats were randomly divided into 2 groups: vehicle-treated normal control group (NC) and 0.45 g/kg HQD-treated normal control group (NC+0.45 g/kg HQD). At the end of 8-week experiment, we measured changes of renal pathological morphology, function, antioxidant enzyme levels and the activation of TGF-β/PPAR-γ/MAPK signaling pathway. Results: After HQD treatment, renal function, including blood urea nitrogen (BUN), 24-h albuminuria and blood glucose level were improved significantly; meanwhile, impaired kidney redox balance was diminished in diabetic rats. The activation of TGF-β, phospho-JNK, phospho-p44/42, p47 and p42 phox was blocked and the decrease in PPAR-γ in diabetic rats was attenuated by treatment with HQD in a dose-dependent manner. Conclusion: These results suggest that HQD shows therapeutic efficacy in DN characterized by renal dysfunction and pathological changes through hypoglycemic and antioxidant effects.

Deoxyribozymes can catalyze various types of reactions mostly with metal ions as their cofactors. Here we demonstrate that three copper compounds with thiosemicarbazide or semicarbazide ligands, are highly active cofactors of Cu2+-dependent deoxyribozymes without any additional reagents. The maximum catalytic rate constant of the deoxyribozyme with dichloro(di-thiosemicarbazide)copper as a cofactor is ∼25-fold faster than Cu2+ cofactor under the same reaction condition. Using a variety of spectroscopies, electrochemistry, and mutagenesis, we demonstrate that both the three-dimensional structure and redox potential of the copper center of the cofactors are essential to the catalysis of deoxyribozymes. The cofactor interacts with the enzyme-substrate complex forming a ternary enzyme-substrate-cofactor complex, which is confirmed by changing the structure of the enzyme-substrate complex through varying the temperature, or mutating the active site of the enzyme and conserved site of the substrate. The result suggests that Cu2+-dependent deoxyribozyme requires a well-defined active site to carry out the catalysis proficiently.