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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.

Background Orsellinic acid (2,4-dihydroxy-6-methylbenzoic acid, OA) and its structural analog o-Orsellinaldehyde, have become widely used intermediates in clinical drugs synthesis. Although the research on the biosynthesis of such compounds has made significant progress, due to the lack of suitable hosts, there is still far from the industrial production of such compounds based on synthetic biology. Results With the help of genome mining, we found a polyketide synthase (PKS, HerA) in the genome of the Hericium erinaceus, which shares 60% amino acid sequence homology with ArmB from Armillaria mellea, an identified PKS capable of synthesizing OA. To characterize the function of HerA, we cloned herA and heterologously expressed it in Aspergillus oryzae, and successfully detected the production of OA. Subsequently, the introduction of an incomplete PKS (Pks5) from Ustilago maydis containing only three domains (AMP-ACP-R), which was into herA-containing A. oryzae, the resulted in the production of o-Orsellinaldehyde. Considering the economic value of OA and o-Orsellinaldehyde, we then optimized the yield of these compounds in A. oryzae. The screening showed that when maltose was used as carbon source, the yields of OA and o-Orsellinaldehyde were 57.68 mg/L and 15.71 mg/L respectively, while the yields were 340.41 mg/Kg and 84.79 mg/Kg respectively in rice medium for 10 days. Conclusions Herein, we successfully expressed the genes of basidiomycetes using A. oryzae heterologous host. As a fungus of ascomycetes, which not only correctly splices genes of basidiomycetes containing multiple introns, but also efficiently produces their metabolites. This study highlights that A. oryzae is an excellent host for the heterologous production of fungal natural products, and has the potential to become an efficient chassis for the production of basidiomycete secondary metabolites in synthetic biology. Graphical Abstract

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.

With the rapid development of high-speed rotating machinery, diaphragm couplings are widely used in energy equipment such as compressors, generators, drilling equipment, and turbine drives by virtue of their high sensitivity, oil resistance and corrosion resistance. However, the theoretical research of this product mainly focuses on the design of diaphragm profile, the combination form between diaphragms, the overall structural form of diaphragm coupling and the axial dynamic characteristics of diaphragm coupling. Therefore, this paper analyzes and summarizes the current research status of diaphragm couplings in the world, and puts forward the problems that need to be solved in the field of diaphragm coupling research, and proposes a new direction for the subsequent research.

Background Cyclic dipeptides are an important class of natural products owing to their structural diversity and biological activities. In fungi, the cyclo-ring system is formed through the condensation of two α-amino acids via non-ribosomal peptide synthetase (NRPS). However, there are few investigations on the functional identification of this enzyme. Additionally, information on how to increase the production of cyclic dipeptide molecules is relatively scarce. Results We isolated the Eurotium cristatum NWAFU-1 fungus from Jing-Wei Fu brick tea, whose fermentation metabolites contain echinulin-related cyclic dipeptide molecules. We cloned the cirC gene, encoding an NRPS, from E. Cristatum NWAFU-1 and transferred it into the heterologous host Aspergillus oryzae. This transformant produced a novel metabolite possessing an l-tryptophan-l-alanine cyclic dipeptide backbone (Cyclo-TA). Based on the results of heterologous expression and microsomal catalysis, CriC is the first NRPS characterized in fungi that catalyzes the formation of a cyclic dipeptide from l-tryptophan and l-alanine. After substrate feeding, the final yield reached 34 mg/L. In this study, we have characterized a novel NRPS and developed a new method for cyclic dipeptide production. Conclusions In this study we successfully expressed the E. Cristatum NWAFU-1 criC gene in A. oryzae to efficiently produce cyclic dipeptide compounds. Our findings indicate that the A. oryzae heterologous expression system constitutes an efficient method for the biosynthesis of fungal Cyclic dipeptides.

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 (

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.

The two-component system VraSR responds to the cell wall-active antibiotic stress in Staphylococcus epidermidis. To study its regulatory function in biofilm formation, a vraSR deletion mutant (ΔvraSR) was constructed using S. epidermidis strain 1457 (SE1457) as the parent strain. Compared to SE1457, the ΔvraSR mutant showed impaired biofilm formation both in vitro and in vivo with a higher ratio of dead cells within the biofilm. Consistently, the ΔvraSR mutant produced much less polysaccharide intercellular adhesin (PIA). The ΔvraSR mutant also showed increased susceptibility to the cell wall inhibitor and SDS, and its cell wall observed under a transmission electron microscope (TEM) appeared to be thinner and interrupted, which is in accordance with higher susceptibility to the stress. Complementation of vraSR in the ΔvraSR mutant restored the biofilm formation and the cell wall thickness to wild-type levels. Transcriptome sequencing (RNA-Seq) showed that the vraSR deletion affected the transcription levels of 73 genes, including genes involved in biofilm formation, bacterial programmed cell death (CidA-LrgAB system), glycolysis/gluconeogenesis, the pentose phosphate pathway (PPP), and the tricarboxylic acid (TCA) cycle, etc. The results of RNA-Seq were confirmed by quantitative real-time reverse transcription-PCR (qRT-PCR). In the ΔvraSR mutant, the expression of icaA and lrgAB was downregulated and the expression of icaR and cidA was upregulated, in comparison to that of SE1457. The transcriptional levels of antibiotic-resistant genes (pbp2, serp1412, murAA, etc.) had no significant changes. An electrophoretic mobility shift assay further revealed that phosphorylated VraR bound to the promoter regions of the ica operon, as well as its own promoter region. This study demonstrates that in S. epidermidis, VraSR is an autoregulator and directly regulates biofilm formation in an ica-dependent manner. Upon cell wall stress, it indirectly regulates cell death and drug resistance in association with alterations to multiple metabolism pathways. IMPORTANCE S. epidermidis is a leading cause of hospital-acquired catheter-related infections, and its pathogenicity depends mostly on its ability to form biofilms on implants. The biofilm formation is a complex procedure that involves multiple regulating factors. Here, we show that a vancomycin resistance-associated two-component regulatory system, VraSR, plays an important role in modulating S. epidermidis biofilm formation and tolerance to stress. We demonstrate that S. epidermidis VraSR is an autoregulated system that selectively responds to stress targeting cell wall synthesis. Besides, phosphorylated VraR can bind to the promoter region of the ica operon and directly regulates polysaccharide intercellular adhesin production and biofilm formation in S. epidermidis. Furthermore, VraSR may indirectly modulate bacterial cell death and extracellular DNA (eDNA) release in biofilms through the CidA-LrgAB system. This work provides a new molecular insight into the mechanisms of VraSR-mediated modulation of the biofilm formation and cell death of S. epidermidis.

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

Based on the dipole blockade effect and with the aid of the superatom (SA) model, we propose a scheme to investigate the correlated evolution of two Rydberg sub-superatoms (SSAs), formed by two spatially separated atomic Rydberg sub-ensembles but in the same blockade region. Starting from the pure separable states, we investigate the in-phase or anti-phase correlated dynamics and explore how two Rydberg SSAs entangle with each other mediated by a single Rydberg excitation. Starting from the entangled states, we discuss the robustness of the system against decoherence induced by the dephasing rate. Our results show that both the correlated evolution of two Rydberg SSAs and their collective-state entanglement are usually sensitive to the number of each Rydberg SSA. This allows us to coherently manipulate the Rydberg ensemble over long distances from the single-quantum level to the mesoscopic level by changing the number of atoms. Furthermore, the method for dividing an SA into two SSAs and obtaining their spin operators without any approximation can be readily generalized to the case of many SSAs. It may have potential promising applications in quantum information processing and provide an attractive platform to study the quantum-classical correspondence, many-body physics and so on.

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.

This paper is concerned with the asymptotic behavior of a p-Landau-Lifschitz type functional with radial structure as parameter goes to zero. We study the concentration compactness and give several global properties in the case of p > 2.

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.

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.

The etiology and pathogenesis of Parkinson's disease (PD) are complicated and have not been fully elucidated, but an important association has been identified between inflammation and PD. In this study, we investigated the role of the nucleotide-binding oligomerization domain, leucine rich repeat and pyrin domain-containing (NLRP) 3 inflammasome, consisting of NLRP3, caspase-1 and cytokines of the IL-1 family, in lipopolysaccharide (LPS)-induced and 6-hydroxydopamine (6-OHDA)-induced PD rats. Microinjection of different doses of caspase-1 inhibitor (Ac-YVAD-CMK, 300 or 1200 ng/rat) was performed for seven consecutive days. Then, rotational behavior, the number of dopamine (DA) neurons in the substantia nigra pars compacta (SNc), and the mRNA and protein expression levels of NLRP3 inflammasome components were measured 14 days after the microinjection setup was established. Results showed that high mRNA and protein expression levels of NLRP3 inflammasome components were observed in the injected side of the LPS- and 6-OHDA-induced PD rats; Ac-YVAD-CMK inhibited the mRNA and protein expression of NLRP3 inflammasome components in both LPS- and 6-OHDA-induced PD rats. Moreover, the number of rotations was significantly decreased, and the number of DA neurons in the SNc improved. Our data indicate that the NLRP3 inflammasome participates in the pathogenesis of PD and that inhibiting the downstream pathway of the NLRP3/caspase-1/IL-1β axis can alleviate the occurrence of PD symptoms, providing a new basis for the prevention and treatment of PD.

In order to investigate the sleep quality and influencing factors in patients with Parkinson's disease (PD), 201 PD patients were enrolled and underwent extensive clinical evaluations. Subjective sleep evaluation was assessed using the Pittsburgh Sleep Quality Index (PSQI), and the Epworth Sleepiness Scale (ESS). It was found that poor sleep quality (77.11%) and excessive daytime sleepiness (32.34%) were commonly seen in PD patients and positively correlated with disease severity. Then 70 out of the 201 PD patients and 70 age- and sex-matched controls underwent a polysomnographic recording. The parameters were compared between PD group and control group and the influencing factors of sleep in PD patients were analyzed. The results showed that sleep efficiency (SE) was significantly decreased (P

The knowledge of the behavior of Te in nickel grain boundaries (GB) is of significant importance for the application of nickel alloys in molten salt reactors. The atomic structures, stabilities, segregation behaviors and diffusion barriers of Te are studied for the bulk, surfaces and four kinds of GBs of nickel. Our first-principles calculations indicate the segregation of Te is most favorable at Σ = 5 (021) GB and the weakest at Σ = 3 (111) GB. The diffusion barriers of Te increase in sequence: Σ = 11 (11), Σ = 9 (221), Σ = 3 (111) and Σ = 5 (021). The calculated diffusion barrier of Te on Σ = 11 (11) is 0.35 eV lower than in the bulk, indicating a fast diffusion of Te along this GB. We also consider the effect of strain on the diffusion and find it to be sensitive to the different GB types. When the tensile strain is up to 4%, the diffusion barriers of Te are lowered by 0.51 eV and 0.15 eV for Σ = 5 (021) and Σ = 11 (11), respectively. In contrast, this effect for Σ = 3 (111) is negligible.

The Biome-BGC (biome biogeochemical cycles) model is widely used for modeling the net primary productivity (NPP) of ecosystems. However, this model ignores soil water changes during the freeze-thaw process in permafrost regions, which may lead to considerable errors in the NPP estimations. In this context we propose a numerical simulation method for improving soil water content during the freeze-thaw process based on the field observation data of soil water and temperature. This approach does not require new parameters and has no impact on other modules. The improvement of soil water content during the freeze-thaw process was then incorporated in the Biome-BGC model for NPP in an alpine meadow in the central Qinghai-Tibetan Plateau (QTP). Interpretation of this data can be found in a research article entitled “An approach for improving soil water content for modeling net primary production on the Qinghai-Tibetan Plateau using Biome-BGC model” (Li et al., 2019). Keywords: Soil water, Biome-BGC, Net primary production, Freeze-thaw process, Qinghai-Tibetan Plateau

Very large-scale gap distances of atmospheric pressure dielectric barrier discharge (DBD) in glow mode are obtained through semiconductor materials. The maximum value of the gap distance is up to 70 mm. Based on the feature of the cathode sheath, Auger neutralization theory, the trapped electron and the accumulated charge in the DBD system, the secondary electron emission is one of the primary reasons for very large-scale gap distances of the DBD to produce glow discharge. Furthermore, the contribution of the effective capacitance, the gas voltage and the discharge power are also discussed. Significant for the research are the development and the practical applications of atmospheric pressure glow discharge in the DBD with very large-scale gap distances.

Endometriosis is a common reproductive disorder in women, with a global prevalence of 10-15%. Long noncoding RNAs (lncRNAs) are critical to gene transcription, cell cycle modulation and immune response. The lncRNA metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) reportedly mediates autophagy of endometrial stromal cells in endometriosis. The present study aimed to evaluate the role and mechanism of MALAT1 in granulosa cells (GCs) in endometriosis. Consequently, MALAT1 expression was upregulated in GCs obtained from patients with endometriosis and in the steroidogenic human granulosa-like tumor cell line KGN. However, MALAT1 knockdown consequently decreased the proliferation and viability of these cells, as determined by MTT and 5-ethynyl-2'-deoxyuridine staining assays. Both Annexin V-fluorescein isothiocyanate/propidium iodide flow cytometry and western blotting performed to detect proapoptotic factors indicated that MALAT1 depletion might promote KGN cell apoptosis. Furthermore, MALAT1 knockdown increased GC autophagy, as evidenced by microtubule-associated protein 1A/1B-light chain 3 (LC3) cleavage upregulation and p62 degradation. In addition, although 5'-AMP-activated protein kinase (AMPK) mRNA expression and protein levels decreased in GCs obtained from patients with endometriosis and KGN cells, MALAT1 knockdown restored AMPK levels. However, addition of BML-275 (MALAT1 inhibitor) to MALAT1-knockdown KGN cells recovered their viability and proliferative capacity and simultaneously reduced their apoptotic and autophagic capacity. Therefore, MALAT1 may regulate GC proliferation via AMPK-mTOR-mediated cell apoptosis and autophagy.

A novel method is proposed to detect chloroform concentrations based on the kinetic parameters using ion mobility spectrometer with a negative corona discharge ion source operating at atmospheric pressure. Unlike conventional sample introduction mode, in this technique, CHCl3 enters into the drift tube from the end of drift region carried by the drift gas. There are two tails before Cl− and (CHCl3)·Cl− ion peaks, which fit to the ions formed in the drift region. Utilizing the kinetic parameters, concentration for CHCl3 can be calculated. This method not only offers a new way to get concentrations of CHCl3 under atmospheric pressure.

The mass-selected infrared photodissociation (IRPD) spectroscopy combined with quantum chemical calculations was utilized to study the interactions between niobium dioxide cation and carbon dioxide molecules. Experimental and calculated results indicate that the CO2 molecules are weakly bound to the NbO2+ cation in an end-on configuration via a charge-quadrupole electrostatic interaction. For n ≥ 6, CO2 molecules in the second shell no longer have contribution to CO2 activation. The similarity of experimental spectra for n ≥ 7 also indicates that ion cores of NbO2+(CO2)n cluster have not changed. Compared with the congeneric YO+ complexes (Phys. Chem. Chem. Phys., 2018, 20, 19314–19320), NbO2+ is found to be thermodynamically and kinetically more difficult to react with CO2.

The Biome-BGC (biome biogeochemical cycles) model is widely used for modeling the net primary productivity (NPP) of ecosystems. However, this model ignores soil water changes during the freeze-thaw process in permafrost regions, which may lead to considerable errors in the NPP estimations. In this study, we proposed a numerical simulation method for improving soil water during the freeze-thaw process based on the field observation data of soil water and temperature. This approach does not require new parameters and has no impact on other modules. The improvement of soil water content during the freeze-thaw process was then incorporated in the Biome-BGC model for NPP in an alpine meadow in the central Qinghai-Tibetan Plateau (QTP). The results indicated that this method effectively reduced the RMSEs (root mean square errors) of the simulated soil moisture, leaf area index, and NPP, indicating that this approach performs well in the Biome-BGC model. This study suggested that the improvement of soil water content during the freeze-thaw process is also applicable to other models and, thus, could be a useful method to reduce the uncertainty of NPP estimations in permafrost regions.

PhoU, a conserved protein that has been proposed to coordinate phosphate import, is a negative regulator of drug tolerance in most bacteria. In Staphylococcus epidermidis , the role of PhoU in biofilm formation and drug tolerance has not yet been investigated. Two PhoU homologs in the genome of S. epidermidis have been identified by the presence of the conserved motif E(D)XXXD of PhoU. We separately constructed Δ phoU1 and Δ phoU2 mutants of S. epidermidis strain 1457. The Δ phoU2 mutant displayed growth retardation, a weakened biofilm formation capacity, a higher sensitivity to H 2 O 2 , and reduced tolerance to multiple antibiotics. However, deletion of phoU1 had no effect on those. We compared the transcriptome profiles of the Δ phoU2 and Δ phoU1 mutants with that of the parent strain. In the Δ phoU2 mutant, expression of genes related to inorganic phosphate uptake was significantly upregulated ( pst operon) and the levels of intracellular inorganic polyphosphate (polyP) were increased. In the Δ phoU2 mutant, expression of enzymes in the pentose phosphate pathway (PPP) was downregulated and less NADP (NADPH) was detected, consistent with the high sensitivity to H 2 O 2 and the growth retardation of the Δ phoU2 mutant. The upregulated expression of ATP synthase was consistent with the high intracellular ATP content in the Δ phoU2 mutant, which may have been related to the lower drug tolerance of the Δ phoU2 mutant. This study demonstrates that PhoU2, but not PhoU1, in S. epidermidis regulates bacterial growth, biofilm formation, oxidative stress, and drug tolerance in association with alterations to inorganic phosphate metabolism, the pentose phosphate pathway, galactose metabolism, the tricarboxylic acid (TCA) or citric cycle, glycolysis and gluconeogenesis, and respiratory reactions. IMPORTANCE PhoU is widely conserved throughout the bacterial kingdom and plays an important role in response to stress and metabolic maintenance. In our study, two PhoU homologs were found in S. epidermidis . The function of phoU2 , but not phoU1 , in S. epidermidis is related to growth, drug tolerance, the oxidative stress response, polyP levels, and ATP accumulation. In addition, phoU2 regulates biofilm formation. Hence, phoU2 is a regulator of both drug tolerance and biofilm formation, which are two bacterial properties that present major challenges to the clinical treatment of infections. Analysis of differential gene expression revealed that phoU2 is involved in fundamental metabolic processes, such as the PPP pathway. These findings indicate that phoU2 is a crucial regulator in S. epidermidis .

A numerical model for analyzing airtraintrack interaction is proposed to investigate the dynamic behavior of a high-speed train running on a track in crosswinds. The model is composed of a traintrack interaction model and a trainair interaction model. The traintrack interaction model is built on the basis of the vehicletrack coupled dynamics theory. The trainair interaction model is developed based on the train aerodynamics, in which the Arbitrary LagrangianEulerian (ALE) method is employed to deal with the dynamic boundary between the train and the air. Based on the airtraintrack model, characteristics of flow structure around a high-speed train are described and the dynamic behavior of the high-speed train running on track in crosswinds is investigated. Results show that the dynamic indices of the head car are larger than those of other cars in crosswinds. From the viewpoint of dynamic safety evaluation, the running safety of the train in crosswinds is basically controlled by the head car. Compared with the generally used assessment indices of running safety such as the derailment coefficient and the wheel-load reduction ratio, the overturning coefficient will overestimate the running safety of a train on a track under crosswind condition. It is suggested to use the wheel-load reduction ratio and the lateral wheelrail force as the dominant safety assessment indices when high-speed trains run in crosswinds.

In this study, the effect of microwave irradiation on reduction of graphene oxide films was investigated. The few-layer graphene (FLG) sheets were prepared by the electrochemical exfoliated method. The reduction process was completed with a microwave power as low as 42 W below a temperature of 250 °C in air. The Raman and XPS spectra demonstrated that a larger amount of oxygen functional groups were removed by microwave irradiation, which is much more effective than the usual method of mild-thermal treatment at 250 °C for 30 min. The FLG films treated by microwave irradiation showed a low value of sheet resistance around 6 × 103 Ω □−1. The results demonstrate that the use of microwave irradiation provides a simple and effective method for eliminating oxygen functional groups to produce highly conductive graphene films.

A novel method to detect the concentration of electronegative VOCs based on the electron attachment rate at atmospheric pressure, through negative discharge in an ion drift tube, is introduced. When the carrier and drift gas in the drift tube are all high-purity nitrogen, electrons are formed by a negative discharge in the ion source, and are injected into the drift region through the shutter grid. When the electronegative sample molecules are continuously introduced into the drift tube from one end, the neutral molecules are ionized through a collision and capture process with the counterflowing swarm of electrons in the drift region. The electron swarm is exponentially diluted as it travels in the drift region. As a result, negative ions are formed in the drift region and a tail appears in the ion mobility spectrum. These spectra include information such as the intensity of the ions and electrons, the drift time, analyte concentration, the electron capture rate etc. The sample concentration can be calculated using the relative equation including information from the spectrum. As examples, in this work the concentration of electronegative samples of CCl4, CHCl3, and 1,1,1-C2H3Cl3 are studied when the electron energy is about 0.54 eV. The sample concentrations obtained in the experiment using this method are in good agreement with the initial concentrations created using a syringe pump. The comparison shows that the process of utilizing electron capture information to determine concentration is effective. This study provides a novel method to determine the concentrations of VOCs at atmospheric pressure.

A series of Bronsted acid-surfactant-combined catalysts (BASCs) functionalised with different acids have been synthesized and applied to catalyze the three-component Mannich reaction with aldehyde, acetone and amine at 25 °C in water. The effects of cation tail length and ions of the ionic liquid and the recyclability of the catalysts and BASC acidity (H0) were investigated. The results demonstrated that the 3-(N,N-dimethyloctylammonium) propanesulfonic acid toluene sulfate ([DOPA][Tos]) provide the best catalytic activity because of the formation of emulsions during the reaction. The catalytic procedure was simple and the catalyst could be recycled 9 times by simple separating processes without noticeably decreasing the catalytic activity.

Mandarin Chinese features a subject-verb-object word order and lacks grammatical agreement of any sort. It is basically a head-last language with the modifiers preceding the head word. Other prominent grammatical features include serial verb construction, resultative complement and the double nominative constructions. My paper focuses on the role of topic and subject in Mandarin, drawing on three views on Chinese syntactic structures, namely, SVO approach, topic-comment approach, and topic-prominence approach. A comparison is made among the different views and a conclusion is drawn that topic-prominent approach may better capture the complexities of Chinese syntax, which definitely contributes to English writing.