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The Covid-19 pandemic has precipitated a global shift to a 'new normal' of online and hybrid learning, significantly affecting language education. This study investigates the impact of emergency remote teaching on language learners' anxiety, examining their preferences for teaching modes and the reasons behind them. Diverging from prior research conducted in well-established digital environments, this inquiry delves into the improvised and stressful context of emergency remote teaching during a pandemic, shedding light on the unexplored facets of the online learning experience. This study, through a quantitative lens, assesses the experiences of 376 English as a foreign language (EFL) students in China, 65 Chinese as a foreign language (CFL) students in Vietnam, and 44 Chinese as a second language (CSL) students enrolled at universities in mainland China. These groups navigated foreign language learning in their home countries amid pandemic constraints, offering a varied landscape of language learning experiences. Our results indicate that different factors trigger anxiety across different groups, despite a general preference for face-to-face learning, which contrasts with the notion that online learning may offer a more relaxed environment. The findings address critical issues that surfaced during the pandemic and explore implications for language education practices in the post-pandemic context. [ABSTRACT FROM AUTHOR]

Titanium (Ti) implants are widely used in orthopedic and dental applications due to their excellent biocompatibility and mechanical properties. However, bacterial adhesion and subsequent biofilm formation on implant surfaces pose a significant risk of postoperative infections and complications. Conventional surface modifications often lack long-lasting antibacterial efficacy, necessitating the development of novel coatings with enhanced antimicrobial properties. This study aims to develop a novel Ag-TiO2-OTS (Silver-Titanium dioxide-Octadecyltrichlorosilane, ATO) nanocomposite coating, through a chemical plating method. By employing a 'resist-killing-disintegrate' approach, the coating is designed to inhibit bacterial adhesion effectively, and facilitate pollutant removal with lasting effects. Characterization of the coatings was performed using spectroscopy, electron microscopy, and contact angle analysis. Antibacterial efficacy, quantitatively evaluated against E. coli and S. aureus over 168 h, showed a significant reduction in bacterial adhesion by 76.6% and 66.5% respectively, and bacterial removal rates were up to 83.8% and 73.3% in comparison to uncoated Ti-base material. Additionally, antibacterial assays indicated that the ratio of the Lifshitz-van der Waals apolar component to electron donor surface energy components significantly influences bacterial adhesion and removal, underscoring a tunable parameter for optimizing antibacterial surfaces. Biocompatibility assessments with the L929 cell line revealed that the ATO coatings exhibited excellent biocompatibility, with minimal cytotoxicity and no significant impact on cell proliferation or apoptosis. The ATO coatings provided a multi-functionality surface that not only resists bacterial colonization but also possesses self-cleaning capabilities, thereby marking a substantial advancement in the development of antibacterial coatings for medical implants. [ABSTRACT FROM AUTHOR]

Understanding the differences in risk perception among various groups is crucial for policy development, and the cultural theory of risk provides significant insights into these group variations. Utilising data from Mainland China during the COVID-19 pandemic, we constructed a structural model that encompasses occupational background, risk culture, and risk perception, examining the interplay between these elements. Our findings reveal that risk culture, as initially conceptualised by Mary Douglas, acts as a mediating factor between occupational roles and the differences in risk perception, offering a deeper understanding of how diverse risk perceptions are shaped across distinct demographic groups. This study underscores the importance of considering cultural factors in risk perception and provides valuable guidance for the development of targeted risk communication and intervention policies. [ABSTRACT FROM AUTHOR]

A parametric model of the second-layer influent distributor is proposed to increase the reaction efficiency of the up-flow anaerobic sludge blanket. The impacts on the flow efficiency of the main parameters, including the length of distribution pipe, that is, the cylinder radius r1, the eccentricity of the nozzle e, and the number of nozzles n1, are investigated. The optimal parameter combination of the second-layer influent distributoris obtained by single factor analysis and orthogonal analysis. Then the two-layer distributor combination model, including the bottom influent distributor and the second-layer influent distributor, is established and the simulations are conducted to study the effect of the two-layer distributor on flow inside the reactor. The simulation results show that the proposed two-layer distributor can achieve a higher mixture efficiency than the single distributor. [ABSTRACT FROM AUTHOR]

The smart responsive materials have become one of the hottest areas of research in oil/water separation field and there are various studies on preparation technologies. However, most of the materials reported were prepared by coating or coupling to attach functional polymer to substrates, which generally had unstable physical and chemical properties and were difficult to be applied in harsh environments. In this work, we fabricated a smart and durable oil/water separation material by one-step foaming method to graft pH-responsive copolymer onto a polyurethane foam (PUF) substrate. The foam exhibited reversible wettability under different pH environments, had excellent oil adsorption capacity (24.78–64.27g/g) and high oil/water separation efficiency (above 98%). Besides, the foam also showed stable performance and excellent recyclability in a series of durability experiments, including mechanical abrasion, light radiation and chemical immersion. The foam with simple preparation process and excellent stability will have promising application prospects in the field of oil/water separation. [ABSTRACT FROM AUTHOR]

With the recent advances in digital technology, creators of information goods such as books, songs, or videos can now self-publish and sell their work directly to consumers, without the help of traditional publishers. In this study, we construct an analytical model to examine the role of online word of mouth in this trend of disintermediation. Online word of mouth can reveal product quality for experience goods and raise awareness to accelerate product diffusion. Intuitively, one would expect that with online word of mouth, creators would be more likely to skip publishers and sell directly to consumers. However, our results suggest that online word of mouth may, in fact, encourage more creators to use publishers for high quality work. Our model also makes predictions on the conditions under which online word of mouth benefits publishers and for what types of products and creators it has the most impact. [ABSTRACT FROM AUTHOR]

In structural health monitoring, the localization of impact is one of the most basic and challenging problems. However, existing technologies are only suitable for obtaining the impact position of plate structures, which hinder their engineering applications. Here, we propose a new method to study the impact position of complex box structures. The proposed method is based on modal parameters and k-means clustering. The modal parameters under different excitation are extracted by applying repeated impact to different positions of the structure, and then the modal constants are clustered to form the cluster centrrs. When the impact occurs at a certain location, the extracted modal constants can be compared with the clustering centres to determine the impact location. The effectiveness of this method is verified by the impact experiment of the gearbox. [ABSTRACT FROM AUTHOR]

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Here we demonstrate a type of pH and redox dual-responsive micelles, which were self-assembled in aqueous solution by an amphiphilic polymer, methoxypoly(ethylene glycol)-cystamine-poly(L-glutamic acid)-imidazole (mPEG-SS-PGA-IM). Considering tumor cells or tissues exhibiting low pH values and high glutathione (GSH) concentration, mPEG-SS-PGA-IM micelles possessed the charge conversion at pH of tumor tissues, which can facilitate cellular uptake of tumor cells. Furthermore, mPEG-SS-PGA-IM micelles can escape from endo/lysosomes based on the proton sponge effect, following degraded by higher concentration of GSH in cytoplasm. CLSM images of HCT116 cells indicated that mPEG-SS-PGA-IM micelles can escape from endo/lysosomes and enter cytoplasm. MTT assay showed that (paclitaxel) PTX-loaded mPEG-SS-PGA-IM micelles had higher cytotoxicity against HCT116 cells compared with PTX-loaded mPEG-PBLG and mPEG-SS-PBLG micelles. These results indicated that these mPEG-SS-PGA-IM micelles, as novel and effective pH- and redox-responsive nanocarriers, have great potential to both improve drug targeting efficiency while also enhancing the antitumor efficacy of PTX. [ABSTRACT FROM AUTHOR]

This paper examines how information provided by online reviews influences firms’ pricing strategy for repeat purchase products. It is commonly understood that online reviews can reduce consumer uncertainty about product characteristics and, therefore, have the potential to increase product demand and firm profits. However, when considering repeat purchase products, online reviews have an additional effect in that they can alter consumers’ propensity to switch among products, which can intensify price competition and lead to lower profits. The strength of these potentially offsetting effects depends on the informativeness of consumer reviews, which is a function of both objective review accuracy and the ability of consumers to obtain information from reviews when their idiosyncratic preferences over product characteristics might differ from the preferences of reviewers. The interplay of these competing effects results in an S‑shaped relationship between the quality of reviews and firm profits. There exists an optimal level of consumer informedness from the firms’ perspective, and competing firms may have incentives to facilitate consumer reviews in some markets but not in others. Given firms’ strategic pricing, consumers may also be worse off as review informativeness increases. [ABSTRACT FROM AUTHOR]

Brucellosis is one of the most common zoonotic diseases with widespread distribution. Traditional methods for diagnosis of brucellosis require long determination times with complex instruments that do not meet the needs of rapid, simple, and convenient analysis. Thus, a newly rapid and simple method for the colorimetric diagnosis of brucellosis was developed using a paper-based enzyme-linked immunosorbent assay (p-ELISA). A total of 135 serum samples were analyzed including 33 samples as healthy controls, 77 samples as the positive group with brucellosis, and 25 samples were infected with other bacteria. The major parameters were optimized for the reported protocol. To evaluate the method, receiver operating characteristic analysis and statistical analysis were carried out using these serum samples. In the established p-ELISA system, only 5 ml of serum were required to detect the antibodies of human brucellosis in suspected brucellosis patients in less than 2 hours. The receiver operating characteristic curve was plotted, and the area under the curve of receiver operating characteristic was 0.996 and shown to be a highly accurate diagnostic test. The sensitivity was determined to be 0.961, the specificity 0.983, and the cutoff value 2.260. The gray scale intensity of the human brucellosis patients group was significantly higher than for the healthy and the non-brucellosis patient groups (p 0.001). This newly developed system allows the rapid and easy diagnosis of human brucellosis. [ABSTRACT FROM AUTHOR]

Lysozyme, an important antibacterial protein, is an enzyme that cleaves the glycosidic bond between N-acetylmuramic acid and N-acetylglucosamine of peptidoglycan in cell walls. The novel lysozyme was purified and characterized from Chinese Lueyang black-bone silky fowl (CBSF) egg white, and its N-terminal amino acid sequence, enzymatic properties, and antibacterial activity were investigated. The CBSF lysozyme was purified using adsorption chromatography, ammonium sulfate precipitation, ion exchange chromatography, and size-exclusion chromatography. The purification fold and yield were 3.28 and 14.69%, respectively. The purified lysozyme was revealed as a single protein band with SDS–PAGE and had a MALDI-TOF/TOF molecular weight of 14305.57 Da and a final specific activity of 3.49 × 105 U/mg protein using Micrococcus lysodeikticus as a substrate. The optimum temperature and pH of the lysozyme were 50 °C and 6.0, respectively. The 20 N-terminal amino acid residues of the purified lysozyme were determined to be KVFGRCELAAAMKRHGLDNY, showing some homology to the N-terminus of the odontophoridae egg white lysozyme. The purified lysozyme exerted a potent antimicrobial activity toward indicator microorganisms, including Bacillus subtilis ATCC 6633, Staphylococcus aureus ATCC 25923, and Escherichia coli ATCC 25922. However, its inhibition of gram-negative activity was weaker than that of the Gram-positive bacteria. [ABSTRACT FROM AUTHOR]

For the fatigue crack embedded in metallic components, the non-collinear transverse wave mixing technique is applied to detect them and image the fatigue damage around crack. When two non-collinear transverse waves with same frequency meet in components, a resonance longitudinal wave can be generated if the resonance condition is satisfied; the mixing nonlinear parameter is applied to evaluate the nonlinearity of detection positions. The non-collinear wave mixing experiments are conducted on components with different length of fatigue crack. By changing the relative position of transducers, different detection positions can be controlled. According to the distribution of mixing nonlinear parameter at vertical direction, the length of fatigue crack at vertical direction can be measured. Furthermore, the mixing nonlinear parameters of different detection positions around fatigue crack are measured, the image of mixing nonlinear parameter can visualise the damage around fatigue crack which is very easy to assess the fatigue damage of components. [ABSTRACT FROM AUTHOR]

The aim of this work is to study the effect of eggshell powder (ESP) on the properties of corn starch (CS) films. It was found that the addition of ESP significantly improved the tensile strength, elongation at break, water vapor and oxygen barrier properties compared to the control film. There was an inductive effect between the C-C bonds on cornstarch skeleton and the O-C-O bond on CaCO3 in the ESP and the number of hydrogen bands increased between starch molecules and ESP particles, which indicated a strong interaction and biocompatibility between the two components. In addition, the organic compounds on the surface of ESP increased the adhesion between CaCO3 particles and CS films matrix. In summary, the ESP, as an enhancement factor, is a good candidate for the development of green food packaging material. [ABSTRACT FROM AUTHOR]

In this paper, we aimed to synthesize a water-soluble hyperbranched polyester with pentaerythritol and trimethylolpropane as branching centers and trimellitic anhydride as waterborne functional groups. The condition and principle of water-soluble hyperbranched resin synthesis were explored. The trimellitic anhydride was used to synthesize water-soluble hyperbranched resin at the most appropriate temperature of 160-170°C. The properties of the resin were characterized by FTIR, hydroxyl value, molecular weight, stability, viscosity, and then the relationship among them under different synthesis conditions was further studied. Results indicated that the water-soluble hyperbranched resin had no delamination for more than 6 months at a solid content higher than 60%. Moreover, the resin was mutual soluble with water at any proportion and kept clear and transparent at same time. After water-soluble hyperbranched resin mixing with amino resin in a ratio of 2.5:1, and curing at 130-135°C for 2 hours, the chemical and mechanical properties of the coating were further measured and characterized. [ABSTRACT FROM AUTHOR]

Lead-contaminated mine tailings were bioremediated using microbial/phyto remediation. The optimum lead accumulation and tolerance capacity of the plant–microbe partnership were investigated, and their mechanisms were evaluated further under varied levels of lead contamination through a flowerpot experiment in a greenhouse. Enzymes activities revealed that bioremediation has improved fertility and metabolism of tailing soil. The removal efficiency of lead was in the order of microbial/phytoremediation > phytoremediation.Solanum nigrumL. was not shown to be a hyperaccumulator for lead.Mucor circinelloidessignificantly enhanced the growth response and lead accumulation in plants more thanMortierellaandTrichoderma asperellum. Moreover,Mortierellawas discovered to have good metal tolerance capacity under high Pb concentrations (1200 and 1600 mg kg−1). The results for lead bioavailability showed that phytostabilisation serves as a major repair pathway forS. nigrumL. Effective fractions were immobilised for decreased bioavailability byT. asperellumandM. circinelloides. On the contrary, an increased amount of lead was mobilised for increased bioavailability byMortierella.This study provides new insights into the feasibility of usingS. nigrumL. and the aforementioned indigenous fungus strains for large-scale bioremediation of mine tailings. [ABSTRACT FROM AUTHOR]

This study sequenced and analyzed the nearly complete mitochondrial genome of Anthocoris kerzhneri. This mitogenome is 16,018 bp long and consisted of 13 protein-coding genes, 20 tRNA genes and two rRNA genes. All protein-coding genes begin with the typical ATN codons and end with TAA or TAG codons. Phylogenetic analysis confirmed that the Reduviidae and Anthocoridae were polyphyletic groups. The Miridae and Tingidae had a sister group relationship. [ABSTRACT FROM AUTHOR]

The complete mitochondrial genome (mitogenome) of Corythucha marmorata has been sequenced and annotated. The entire mitogenome is a typical circle double-stranded DNA molecule of 15,635b p and consisted of 37 genes and a control region in the typical invertebrate mitochondrial gene arrangement. Phylogenetic analysis recovered the momophyly of Gerromorpha, Enicocephalomorpha and Cimicomorpha. [ABSTRACT FROM AUTHOR]

Two series of polybenzoxazoles (PBOs) containing trifluoromethyl or sulfone groups were synthesized via solution condensation polymerization. The polymers were characterized by FT-IR,1H-NMR, thermogravimetric analysis (TGA), UV-vis absorption, and photoluminescence (PL) spectroscopy. The solubility of these polymers was greatly enhanced over that of pure PBO and some of them could dissolve well in polar solvents, such as N-methyl-2-pyrrolidone (NMP) and 2,5-Dimethylfuran (DMF). Due to the introduction of trifluoromethyl and sulfone groups, the UV absorption peaks and the emission peaks of all the polymers blue shifted, compared with those of pure PBO. The polymers derived from 2,2-bis(3-amino-4-hydroxyphenyl) hexafluoropropane (6FAP) had a lower dielectric constant, which is due to the strong electron-withdrawal inductive effect, compared to that of the polymers derived from 3,3-diamino-4,4-dihydroxydiphenylsulfone (6SAP). [ABSTRACT FROM AUTHOR]

A pyridine-based polybenzobisoxazole (PBOPy) was synthesized via solution condensation polymerization. The polymer was characterized by Fourier transform infrared spectroscopy, wide-angle X-ray diffraction, thermogravimetric analysis, ultraviolet-visible (UV-Vis) absorption spectroscopy, photoluminescence (PL) spectroscopy, electrochemical cyclic voltammetry, and time-resolved PL decay dynamics. Results showed that the introduction of pyridine groups made the oxidation potential (1.82 eV) relatively larger than that of poly(p-phenylenebenzobisoxazole) (PBO) (1.65 eV), while the reduction potential (−1.18 eV) was smaller than that of PBO (−1.28 eV). It can be concluded, by comparing UV-Vis absorption spectroscopy and PL spectroscopy of PBOPy in film and in methanesulfonic acid (MSA), that PBOPy has a stronger protonation effect in the latter. The optical properties of PBOPy exhibited a PL emission band at 473 nm in thin films and a strong orange fluorescence (498 nm) after being protonated with MSA. The protonation effect resulted in a large Stokes shift, about 71 nm. [ABSTRACT FROM PUBLISHER]

The improvement of DNA's bioactivities by altering their structure is meaningful for their biological applications, ranging from DNA condensation study to gene therapeutic research. In this study, we treated the plasmid DNA with alkali and investigated the structure and the condensation efficiency of the alkali-treated DNA. We noticed that the alkali treatment could significantly increase the DNA condensation efficiency with spermidine and polyethylenimine (PEI). In addition, due to the improved interactions between the alkali-treated DNA and PEI, gene transfection experiments could be performed in the presence of less PEI. This research can contribute to the creation of a universal method to enhance the interaction between DNA and gene delivery vectors by alkali treatment, and should have significant potential in the field of gene therapy. [ABSTRACT FROM AUTHOR]

A series of fluorine-containing diblock copolymers based on lauryl methacrylate and 1H,1H,2H,2H-perfluoroalkyl acrylate have been prepared by atom transfer radical polymerization (ATRP). The preparation process of PLMA-Br macroinitiators was controlled within a reasonable time corresponding to the ln [M0]/[Mt]∼time plot of the reaction. FTIR, 1H-NMR, GPC and fluorine-element analysis (FEA) were used to characterize the synthesized block copolymers. The solid surface activity of these polymers was demonstrated by contact angle measurement. The polymer films prepared by block copolymers with more than three fluorinated units showed low dispersion force contributions to the surface energy indicating the presence of the fluorinated block at the surface. The surface activity in solutions was measured by drop-weight method. Ii is interesting to find, when the fluorine weight percentage is controlled constant, that PLMA-b-PFAEA with larger molecular size is more prominent in exploiting the fluorinated structure to reduce the surface tension of solutions. The block copolymer's ability in reducing surface tension of solutions also depends on the type of solvent. [ABSTRACT FROM AUTHOR]

Rising global wind power capacity urgently requires effective real-time turbine monitoring. Complex installations, high maintenance costs, and the occasional need for turbine shutdown hinder conventional monitoring methods. Acoustic-based techniques, while cost-efficient for health assessments, currently face challenges with detection precision and signal processing capabilities in complex acoustic environments. To overcome these challenges, this study proposes a low-cost, AI-driven acoustic-based health monitoring system framework for wind turbine blades, featuring enhanced detection accuracy and signal processing capabilities in complex sound environments. Firstly, a microphone array is employed to capture blade sounds with rich spatial attributes, while beamforming algorithms with a fixed orientation integrate prior spatial information. Furthermore, to further strengthen signal processing and fault detection capabilities, the Transformer model based on self-attention mechanisms is employed for feature extraction and fault diagnosis. An actual wind turbine blade health monitoring system is designed and developed to validate the usability of the proposed framework. Experimental results based on a scaled-down wind turbine model validate the proposed algorithm's effectiveness and practicality, presenting an effective approach in the wind turbine blade health monitoring domain. [ABSTRACT FROM AUTHOR]

Natural products comprise an important class of biologically active molecules. Many of these compounds derived from natural sources exhibit specific physiologic or biochemical effects. An example of a natural product is chitosan, which is enriched in the shells of certain seafood that are frequently consumed worldwide. Like other natural products, chitosan has the potential for applications in clinical medicine and perhaps in cancer therapy. Toward this end, the immunomodulatory or anti-cancer properties of chitosan have yet to be reported. In this study, we discovered that chitosan enhanced the anti-tumor activity of natural killer (NK) cells by activating dendritic cells (DCs). In the presence of DCs, chitosan augmented IFN-γ production by human NK cells. Mechanistically, chitosan activated DCs to express pro-inflammatory cytokines such as interleukin (IL)-12 and IL-15, which in turn activated the STAT4 and NF-κB signaling pathways, respectively, in NK cells. Moreover, chitosan promoted NK cell survival, and also enhanced NK cell cytotoxicity against leukemia cells. Finally, a related in vivo study demonstrated that chitosan activated NK cells against B16F10 tumor cells in an immunocompetent syngeneic murine melanoma model. This effect was accompanied by in vivo upregulation of IL-12 and IL-15 in DCs, as well as increased IFN-γ production and cytolytic degranulation in NK cells. Collectively, our results demonstrate that chitosan activates DCs leading to enhanced capacity for immune surveillance by NK cells. We believe that our study has future clinical applications for chitosan in the prevention or treatment of cancer and infectious diseases. [ABSTRACT FROM AUTHOR]