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Schematic illustration of the developed strategy of the P 2/O3-NLiFMNb material. In this work, we adopted a simple Li&Nb co-doping modification method to modify the layered oxide cathode material for sodium-ion batteries, achieving dual modification effects of structural control and surface modification. Compared to the pristine, the modified material exhibits excellent cycling stability and rate performance. [Display omitted] Layered sodium iron manganese oxide cathodes have attracted great interest owing to their high specific capacity and cost-effective metal resources, while the detrimental phase transitions and surface structural degradation severely limit their commercial applications. In this work, the bulk and surface structure stability of a P 2-Na 0.67 Fe 0.5 Mn 0.5 O 2 cathode can be synergically enhanced by a one-step Li/Nb co-doping strategy. Structural characterizations reveal that Li doping promotes the formation of P 2/O3 biphasic structure and makes the unfavorable P 2-OP4 phase transition convert into a smooth solid-solution reaction. Nb doping enhances the mobility of sodium ions and forms strong Nb-O bonds, thereby enhancing the stability of the TMO 2 layer structure. In particular, the Nb element induces the surface reorganization of an atomic-scale NaNbO 3 coating layer, which could effectively prevent the dissolution of metals and surface side reactions. The synergistic mechanism of enhanced electrochemical performance is proved by multiple characterizations during cycling. As a result, the as-prepared Na 0.67 Li 0.1 Fe 0.5 Mn 0.38 Nb 0.02 O 2 exhibits improved capacity retention of 85.4 % than raw material (45.7 %) after 100 cycles at 0.5C (1C = 174 mA g−1) within 2.0–4.0 V. This co-regulating strategy provides a promising approach to designing highly stable sodium-ion battery cathodes. Furthermore, a full cell of Na 0.67 Li 0.1 Fe 0.5 Mn 0.38 Nb 0.02 O 2 with hard carbon displays excellent cycling stability (85.1 % capacity retention after 100 cycles), making its commercial operation possible. This synergistic strategy of biphasic structure and surface reorganization is a critical route to accelerate the application of layer oxide cathodes. [ABSTRACT FROM AUTHOR]

Blind Omnidirectional Image Quality Assessment (BOIQA) is of great significance to the development of the immersive media technology. Most BOIQA metrics are achieved by projecting the raw spherical OIs into other plane spaces for better feature representation. For these metrics, the semantic information at the shared boundaries of the adjacent views are prone to be destroyed, hindering the semantic understanding and further performance improvement. To tackle this problem, we propose a lightweight but effective BOIQA metric via replenishing the damaged semantic information. Specifically, a multi-stream semantic information replenishment module is constructed by the multi-scale feature representation, which is designed to restore the destroyed semantic information from two adjacent views. For module learning, more than 20,000 image triplets are further built. Then, the restored features are integrated for the final quality prediction. To testify the effectiveness of the proposed method, extensive experiments are conducted on the public OIQA databases, and the results prove the superior performance of the proposed method. • A multi-stream semantic information replenishment (SIR) module is proposed. • A database consists of more than 20,000 image triplets is constructed. • Extensive experiments have demonstrated the superiority of the proposed method. [ABSTRACT FROM AUTHOR]

Integrating the reciprocity lens and the componential model of creative process, we develop novel theoretical insights regarding how and when empowering leadership promotes employee creativity. In a scenario-based experimental study of 198 participants (Study 1), we found that empowering leadership was positively related to employees' felt obligation for constructive change, especially for employees who had a high level of organizational identification. In a three-wave field survey study of 221 employees and their direct supervisors (Study 2), we found that organizational identification strengthened the positive effects of empowering leadership on employees' felt obligation for constructive change. Furthermore, employees' felt obligation for constructive change was positively associated with job crafting behavior, subsequently employee creativity. Our research generates valuable insights into how and when empowering leadership enhances employee creativity. • Empowering leadership had a positive effect on felt obligation for constructive change. • Felt obligation for constructive change had a positive effect on job crafting. • Job crafting had a positive effect on employee creativity. • Findings showed the sequential mediating role of felt obligation for constructive change and job crafting. • Findings showed the moderating role of organizational identification. [ABSTRACT FROM AUTHOR]

The quantum Boltzmann-Bose equation describes a large system of Bose-Einstein particles in the weak-coupling regime. If the particle interaction is governed by the inverse power law, the corresponding collision kernel has angular singularity. In this paper, we give a constructive proof of the coercivity estimate for the linearized quantum Boltzmann-Bose operator to capture the effects of the singularity and the fugacity. Precisely, the estimate explicitly reveals the dependence on the fugacity parameter before the Bose-Einstein condensation. With the coercivity estimate, the global in time well-posedness of the inhomogeneous quantum Boltzmann-Bose equation in the perturbative framework and stability of the Bose-Einstein equilibrium can be established. [ABSTRACT FROM AUTHOR]

[Display omitted] • NiC/Mo 2 C/NF electrode heterostructure was in situ constructed. • NiC/Mo 2 C nanorods array exhibits excellent HER activity (31 mV at 10 mA cm−2, 264 mV at 500 mA cm−2). • NiC/Mo 2 C showed long term durability with negligible potential change for 200 h. • Balances the adsorption/desorption energy of the H-reaction intermediate, reduces the dissociation energy. The problem limiting the use of hydrogen evolution reactions in industry is the inability of electrocatalysts to operate stably at high current densities, so the development of stable and efficient electrocatalysts is important for hydrogen production by water splitting. By designing a rational interface engineering not only can the problem of limited number of catalytic sites in the catalyst be solved, but also can facilitate electron transfer, thus enhancing the efficiency of water splitting. Here, we designed a two-stage chemical vapour deposition method to construct NiC/Mo 2 C nanorod arrays on nickel foam to enhance the electrocatalytic ability of the catalysts, which exhibited efficient HER catalytic activity due to their special tentacle-like nanorod structure and abundant heterogeneous junction surfaces, which brought about abundant active sites as well as promoted electron transfer capability. The resulting catalysts provide current densities of 10, 100 and 500 mA cm−2 with overpotentials of 31, 153 and 264 mV, and exhibit excellent stability at current densities of 10 mA cm−2 for 200 h. This discovery provides a new idea for the rational design of catalysts with special morphologies. [ABSTRACT FROM AUTHOR]

Rapa functionalized carbon dots (Rapa-CDs) were target-oriented synthesized via free radical polymerization combination with hydrothermal carbonization technology. Rapa-CDs has a high synthetic yield of 63%. The solubility of Rapa-CDs with 9.41 g is improved 3.6×104 times higher than that of Rapa (2.6×10-4 g). Rapa-CDs show the ability to scavenge ROS, and suppress cell senescence via anti-oxidative stress and mTOR. [Display omitted] • Rapa-CDs with synthetic yield of 63% were target-oriented synthesized. • Rapa-CDs increase Rapa solubility by 3.6 × 104 times and show ROS scavenging ability. • Rapa-CDs suppress vascular cell senescence via anti-oxidative stress and mTOR. Suppression of vascular cell senescence is of great significance in preventing cardiovascular diseases such as hypertension and atherosclerosis. The oxidative stress damage caused by reactive oxygen species (ROS) can lead to cellular senescence. Rapamycin (Rapa) is well known to suppress cell senescence via mammalian target of rapamycin (mTOR) pathway. However, poor water solubility and lack of ROS scavenging ability limit the further development of Rapa. To improve the solubility of Rapa and endow with ROS scavenging ability, Rapa functionalized carbon dots (Rapa-CDs) are target-oriented synthesized via free radical polymerization combination with hydrothermal carbonization. Rapa-CDs improve the solubility of Rapa and show ROS scavenging abilities. The solubility of Rapa-CDs with 9.41 g is improved 3.6 × 104 times higher than that of Rapa (2.6 × 10-4 g). The half maximal inhibitory concentration (IC 50) of Rapa-CDs toward hydroxyl radical (•OH) and 2,2-Diphenyl-1-picrylhydrazyl free radical (DPPH•) are 0.18 and 0.17 mg/mL, respectively. Rapa-CDs show anti-oxidative stress effect in HEVECs (Human Umbilical Vein Endothelial Cells) via reducing ROS levels by 87 %. Rapa-CDs alleviate HUVECs senescence by suppressing mTOR overactivation, attenuate the expression of P53, P21 and P16. The study demonstrates the target-oriented synthesis of drugs functionalized CDs with anti-senescence via dual-pathway of anti-oxidative stress and mTOR. [ABSTRACT FROM AUTHOR]

[Display omitted] • OG c3 exhibits broad-spectrum anti-biofilm activity by concurrently targeting bacterial membrane lipids, DNA, and proteins. • OG c3 ′s unique alternating amphiphilic structure facilitates penetration into the dense extracellular biofilm matrix. • OG c3 effectively eliminates biofilms and exerts synergistic effects with Vancomycin. • The potent anti-biofilm capabilities of OG c3 against drug-resistant bacteria are validated through robust in vitro and in vivo evaluations. The development of effective antibacterial drugs to combat bacterial infections, particularly the biofilm-related infections, remains a challenge. There are two important features of bacterial biofilms, which are well-known critical factors causing biofilms hard-to-treat in clinical, including the dense and impermeable extracellular polymeric substances (EPS) and the metabolically repressed dormant and persistent bacterial population embedded. These characteristics largely increase the difficulty for regular antibiotic treatment due to insufficient penetration into EPS. In addition, the dormant bacteria are insensitive to the growth-inhibiting mechanism of traditional antibiotics. Herein, we explore the potential of a series of new oligopyridinium-based oligomers bearing a multi-biomacromolecule targeting function as the potent bacterial biofilm eradication agent. These oligomers were rationally designed to be "charge-on-backbone" that can offer a special alternating amphiphilicity. This novel and unique feature endows high affinity to bacterial membrane lipids, DNAs as well as proteins. Such a broad multi-targeting nature of molecules not only enables its penetration into EPS, but also plays vital roles in the bactericidal mechanism of action that is highly effective against dormant and persistent bacteria. Our in vitro , ex vivo , and in vivo studies demonstrated that OP c3 , one of the most effective derivatives, was able to offer excellent antibacterial potency against a variety of bacteria and effectively eliminate biofilms in zebrafish models and mouse wound biofilm infection models. [ABSTRACT FROM AUTHOR]

Photocatalysts based on Z-scheme heterostructure have been extensively investigated for CO 2 reduction and hydrogen production, which solve the problem of high electron-hole pair complexation and low reduction and oxidation capacity in photocatalysts. Here, two-dimensional CuTiO 3 /g-C 3 N 4 (CTO/CN) photocatalysts with directly Z-scheme heterostructure are prepared by effective manipulation of different components of CuTiO 3 (CTO) nanoparticles on 2D (two-dimension) porous g-C 3 N 4 (CN) nanosheets via in-situ growing strategy. Benefited from the special electronic structure, it demonstrates that the 4.0 % CTO/CN sample has an excellent photocatalytic activity for the reduction of CO 2 to H 2 (at a speed of 19.56 μmol g−1 h−1) and CO (at a speed of 19.93 μmol g−1 h−1), which are upper than those of pure g-C 3 N 4 by 43.5 and 17.1 times, respectively. Furthermore, the 4.0 % CTO/CN sample exhibits utstanding performance in electrocatalytic hydrogen production. This synthetic strategy is useful for constructing a 2D Z-scheme heterostructure for applications in energy-related areas. Schematic diagram of electrochemical hydrogen precipitation and carbon dioxide reduction of CuTiO 3 /CN heterojunction composites prepared by in situ growth method. [Display omitted] • A series of CuTiO 3 /g-C 3 N 4 nanosheets were prepared by applying in situ growth method. • CuTiO 3 /g-C 3 N 4 exhibits excellent performance for CO 2 reduction under visible light irradiation. • The 4.0 % CTO/CN had excellent electrochemical stability performance under neutral conditions. [ABSTRACT FROM AUTHOR]

This numerical study aims to investigate the effect of inlet turbulence intensity T u (0.05 – 5.0%) on flow-induced vibration of an elastic cylinder with fixed ends placed next to a rigid cylinder of the same diameter and length in axial flow. Turbulent flow structure and fluid-structure interaction are captured using large eddy simulation and two-way coupling calculation, respectively. It is found that T u produces a pronounced effect on vibration characteristics of the elastic cylinder. Given a dimensionless velocity U̅ (i.e., 3.49, less than critical U̅ for onset of buckling), root-mean-square vibration amplitude A rms ⁎ increases rapidly with increasing T u from 0.7% to 5.0% for any given center-to-center cylinder spacing P⁎ (1.20 – ∞). This change in A rms * is attributed to the interactions between turbulent structures of different scales, where interactions between large-scale eddies result in the formation of small-scale eddies in the interstitial flow between the cylinders, thus enhancing greatly the flow instability and hence A rms *. Another interesting phenomenon takes place at U̅ = 7.62 (beyond the critical U̅ for onset of buckling) and P⁎ = 1.80, where the elastic cylinder buckles into a new dynamic equilibrium state. As T u increases from 0.3% to 1.5%, the flutter instability occurs merely along the y direction that is normal to the plane of two cylinders axes and also normal to main stream direction. It has been found that the high- T u flow triggers two vortices in this direction, giving rise to two regions of different pressures around the cylinder. The two regions reposition quasi-periodically themselves, thus producing lateral forces that account for this flutter instability in the y direction. Scaling analysis of the dependence of A rms ⁎ on T u and U̅ reveals that the relationship A rms ⁎ = g 1 (T u , U̅) may be reduced to A rms ⁎ = g 2 (U̅ eff); g 1 and g 2 are different functions and the scaling factor U̅ eff = U̅ TF , where TF is the turbulence factor that accounts for the effect of T u on A rms ⁎. The scaling law is discussed in detail, along with the physical meanings of U̅ eff. [ABSTRACT FROM AUTHOR]

[Display omitted] The 2H-MoS 2 /nitrogen-doped carbon (2H-MoS 2 /NC) composite is a promising anode material for potassium-ion batteries (PIBs). Various transition metal doping has been adopted to optimize the poor intrinsic electronic conductivity and lack of active sites in the intralayer of 2H-MoS 2. However, its optimization mechanisms have not been well probed. In this paper, using Cobalt (Co) as an example, we aim to investigate the influence of transition metal doping on the electronic and mechanical properties and electrochemical performance of 2H-MoS 2 /NC via first-principles calculation. Co doping is found to be effective in improving the electronic conductivity and the areas of active sites on different positions (C surface, interface, and MoS 2 surface) of 2H-MoS 2 /NC. The increased active sites can optimize K adsorption and diffusion capability/processes, where general smaller K adsorption energies and diffusion energy barriers are found after Co doping. This helps improve the rate performance. Especially, the pyridinic N (pyN), pyrrolic N (prN), and graphitic N (grN) are first unveiled to respectively work best in K kinetic adsorption, diffusion, and interfacial stability. These findings are instructive to experimental design of high rate 2H-MoS 2 /NC electrode materials. The roles of different N types provide new ideas for optimal design of other functional composite materials. [ABSTRACT FROM AUTHOR]

In this study, we present a straightforward dual-readout immunoassay for sensitive and specific detection of zearalenone (ZEN) using the inner filter effect (IFE) and p-phenylenediamine (PPD). 2-aminoterephthalic acid (PTA-NH 2) is an organic compound that exhibits strong fluorescence at 420 nm. In the presence of horseradish peroxidase (HRP) and hydrogen peroxide (H 2 O 2), PPD was oxidized to 2,5-diamino-N, N'-bis(p-aminophenyl)-1,4-benzoquinone di-imine (PPDox). The fluorescence of PTA-NH 2 was quenched due to the IFE effect, resulting from the effective overlap between the UV–vis absorption spectra of PPDox and the fluorescence spectra of PTA-NH 2. Furthermore, PPDox was completely oxidized to p-benzoquinone (PBQ) by sulfuric acid, exhibiting a strong absorption peak at 415 nm and a yellow color. Consequently, a dual-readout immunoassay based on IFE and PPD was developed for the detection of ZEN. The limits of detection for the fluorescent and colorimetric modes were 0.011 ng/mL and 0.019 ng/mL, respectively. The approach can be used to efficiently and accurately detect ZEN in real samples due to the high sensitivity, specificity, and consistency of the dual-readout modes. • A novel IFE and PPD-based dual-readout immunoassay was developed for zearalenone. • This strategy is simple, economical and reproducible. • The LOD of proposed immunoassay was 130-fold lower than that of conventional ELISA. • The immunoassay is simple and does not require any nanomaterials. [ABSTRACT FROM AUTHOR]

Natural products can overcome the limitations of conventional chemotherapy. Acetyl-11-keto-beta-boswellic acid (AKBA) as a natural product extracted from frankincense, exhibited chemotherapeutic activities in different cancers. However, whether AKBA exerts inhibiting effect of oral squamous cell carcinoma (OSCC) cells growth and the mechanism need to be explored. We attempted to investigate the therapeutic effects of AKBA against OSCC and explore the mechanism involved. Here we attempt to disclose the cell-killing effect of AKBA on OSCC cell lines and try to figure out the specifical pathway. The presence of increase autophagosome and the production of mitochondrial reactive oxygen species were confirmed after the application of AKBA on OSCC cells, and RAB7B inhibition enhanced autophagosome accumulation. Though the increase autophagosome was detected induced by AKBA, autophagic flux was inhibited as the failure fusion of autophagosome and lysosome. Cal27 xenografts were established to verify the role of anti-OSCC cells of AKBA in vivo. Based above findings, we speculate that natural product AKBA suppresses OSCC cells growth via RAB7B-mediated autophagy and may serve as a promising strategy for the therapy of OSCC. • Natural products AKBA: AKBA exerts the effect of inhibiting OSCC cell growth. • Autophagy: Autophagy may mediate apoptosis in OSCC cell death induced by AKBA. • RAB7B: RAB7B inhibition enhanced autophagosome accumulation induced by AKBA. [ABSTRACT FROM AUTHOR]

Metakaolin-based geopolymers are very promising materials for improving the safety of low and intermediate level radioactive waste disposal, with respect to ordinary Portland cement, due to their excellent immobilization performance for Cs+ and superior chemical stability. However, their application is limited by the fact that the leaching behavior of Cs+ is susceptible to the presence of other ions in the environment. Here, we propose a way to modify a geopolymer using perfluorodecyltriethoxysilane (PDFS), successfully reducing the leaching rate of Cs+ in the presence of multiple competitive cations due to blocking the diffusion of water. The leachability index of the modified samples in deionized water and highly concentrated saline water reached 11.0 and 8.0, respectively. The reaction mechanism between PDFS and geopolymers was systematically investigated by characterizing the microstructure and chemical bonding of the material. This work provides a facile and successful approach to improve the immobilization of Cs ions by geopolymers in real complex environments, and it could be extended to further improve the reliability of geopolymers used in a range of applications. [Display omitted] • A novel modification of geopolymer using perfluorodecyltriethoxysilane (PDFS) is proposed. • The diffusion of water in PDFS-modified geopolymer slows down significantly. • The Cs + leaching rate and the cumulative leaching fraction of PDFS-modified geopolymer reduce significantly in the leaching tests. • PDFS-modified geopolymer exhibits excellent reliability in complex environments with the presence of multiple competing ions. [ABSTRACT FROM AUTHOR]

In this work, a dual-mode immunoassay to detect Ochratoxin A (OTA) was developed relied on p -nitrophenyl phosphate (PNPP) and 2-aminoterephthalic acid (PTA-NH 2). This proposed immunoassay based on microplate immunoenzyme technique used alkaline phosphatase (ALP) as a label for forming immune complexes. The ALP was used to catalyze the dephosphorization of PNPP to generate yellow p -nitrophenol (PNP). Since the absorption wavelength of PNP overlapped with the fluorescence emission of PTA-NH 2 , the fluorescence of PTA-NH 2 can be quenched by PNP. The color of PNP and the fluorescence of PTA-NH 2 were used as double signals to detect OTA. In this dual-mode immunoassay, the limit of detection (LOD) and the linear detection range of fluorescence mode were 0.57 ng/mL (about 0.57 μg/kg) and 1.56–50.00 ng/mL (about 1.56–50.00 μg/kg), respectively. For absorbance mode, the LOD and linear range were 0.07 ng/mL (about 0.07 μg/kg) and 0.39–25.00 ng/mL (about 0.39–25.00 μg/kg), respectively. Both detection modes showed good selectivity for OTA. The recoveries rates of fluorescence mode and absorption mode in maize flours were 91.80–128.85% and 100.10–114.00%, respectively. • The dual-mode immunoassay was developed based on PNPP and PTA-NH 2. • This assay based on microplate immunoenzyme technique used ALP as a label for forming immune complexes. • The mutual verification of the two modes improved the accuracy of analysis method. • The dual-mode immunoassay had a wide linear range and low LOD. [ABSTRACT FROM AUTHOR]