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Ultra-stable CoS x /CdS photocatalysts were fabricated by the ZIF-67-templated one-pot solvothermal route for photocatalytic Cr(VI) reduction under visible light. • CoS x /CdS composites were controllably fabricated by ZIF-67-templated solvothermal route. • Different photocatalytic activities were obtained depending on the CoS x -to-CdS molar ratios. • Highest visible-light photocatalysis for Cr(VI) reduction was expected with 100% efficiency. • Long-term stability could be maintained for the photocatalytic cycles. • A photocatalytic mechanism of direct Z-scheme heterojunction was proposed. Visible-light-driven and ultra-stable CoS x /CdS photocatalysts were controllably fabricated by the ZIF-67-templated one-pot solvothermal route for highly efficient photocatalytic Cr(VI) reduction. It was discovered that the resulting CoS x /CdS composites could present different photocatalytic activities controllably depending on the CoS x -to-CdS molar ratios used. The one with 1/16 M ratio could display the highest photocatalytic reduction performance for Cr(VI) with the efficiency up to 100% within 30 min, which is 5.6-fold and 2.1-fold higher than that of pristine CoS x and CdS, respectively. Herein, the components of CoS x and CdS with well-matched energy-band structures might serve separately as the electrons donor and the holes quencher to prolong the lifetime of photogenerated electrons in CoS x /CdS composites. A direct Z-scheme heterojunction could be thus constructed for promoting the charge carrier transferring with the improved redox abilities, leading to the robust photocatalysis of CoS x /CdS photocatalyst. Moreover, the developed CoS x /CdS photocatalyst could present superior stability with the structure and activity well survived after five photocatalytic cycles. This work may pave the way towards the controllable construction of a direct Z-scheme photocatalytic system by synergistically combining two kinds of components with matched energy-band structures, achieving the enhanced photocatalysis for the wide applications in the environmental remediation field. [ABSTRACT FROM AUTHOR]

Xylem vessels are the channels used for water transport in Jatropha curcas L. Vessel complexity has a great influence on water transport. Therefore, using anatomical experiments and numerical simulations, the water transport characteristics of J. curcas L xylem vessels with perforation plate and secondary wall thickening (pit structures) were analyzed. The results showed that the xylem vessel in J. curcas provided a low resistance path. The xylem vessel resistance was composed of three elements: smooth vessels, secondary wall thickening and perforation plate. The proportion of smooth vessel resistance was the largest, accounting for 66.20% of the total resistance. Then the secondary wall thickening resistance accounted for 30.20% of the total resistance, and finally the perforation plate resistance accounted for 3.60% of the total resistance. The total resistance of the vessel model was positively correlated with the pit depth, perforation plate height and perforation plate width and negatively correlated with the vessel inner diameter and pit membrane permeability. The vessel inner diameter and the pit depth had a great influence on the total resistance. The total resistance of the vessel inner diameter of 52 µm was 89.15% higher than that of 61 µm, the total resistance of the pit depth of 5.6 µm was 21.98% higher than that of 2.6 µm. The pit structure in the secondary wall thickening caused the vessel to be transported radially, and the radial transmission efficiency of the vessel was positively correlated with the pit depth and pit membrane permeability and negatively correlated with the vessel inner diameter. The pit membrane permeability had the greatest influence on the radial transmission efficiency, and its radial transmission efficiency was 0–5.09%. [ABSTRACT FROM AUTHOR]

• A photoelectrochemical sensor was developed for the "signal-on" analysis of Hg2+. • Hollow CoS x @CdS polyhedrons were fabricated by ZIF-67-templated solvothermal route. • Direct Z-scheme CoS x @CdS photocatalysts were utilized as the recognition probes. • New Z-scheme heterojunction of CoS x @CdS/HgS was formed by the selective ion-exchange. • This PEC sensor can facilitate the detection of Hg2+ with concentrations down to 2.0 pM. A visible-light-driven photoelectrochemical (PEC) sensor has been developed for probing Hg2+ with "turn-on" signal output using hollow CoS x @CdS polyhedron as direct Z-scheme photocatalyst and Hg2+-recognition probe. The CoS x @CdS heterojunction photocatalysts were fabricated by growing CdS nanoparticles on the surface of cobalt sulfide (CoS x) via one-pot solvothermal route using metal-organic frameworks (MOFs) of ZIF-67 polyhedrons as the sacrificial templates and cobalt precursors. It was discovered that the photocurrent responses of the CoS x @CdS-modified ITO electrodes could be specifically turned on by Hg2+, in contrast to these of the CoS x or CdS-modified ones showing no significant Hg2+-induced photocurrent. Under visible light irradiation, herein, the synergetic combination of CoS x and CdS components could improve the carriers transferring of PEC system. More importantly, the photocurrents of the PEC sensor could be greatly enhanced in the presence of Hg2+ through the selective ion-exchange reaction to trigger the in-situ formation of a new Z-scheme heterojunction of CoS x @CdS/HgS photocatalysts, achieving the further promoted charge transferring and suppressed recombination of photogenerated electron-hole pairs. The developed double heterojunctions-based PEC sensors can detect Hg2+ with the concentrations ranging from 0.010 to 1000 nM, which performances are much better than those of the current PEC analysis methods. Besides, such a MOF-templated one-pot construction route may pave the way toward the design of various direct Z-scheme heterojunction photocatalysts of PEC probes of great interest. [ABSTRACT FROM AUTHOR]

• A photoelectrochemical sensor was developed for the "signal-on" analysis of Hg2+. • Bead chain-like Ag 2 S were integrated with ZnS to be coated onto the ITO electrodes. • Ag 2 S and ZnS were utilized separately as the sensitizer and recognition probe. • Hg2+ can conduct a Zn-to-Hg exchange to form HgS/ZnS@Ag 2 S heterojunction. • This sensor can facilitate the detection of Hg2+ with concentrations down to 1.0 pM. A visible-light-driven photoelectrochemical (PEC) sensor has been developed for the "signal-on" analysis of Hg2+ by the synergetic combination of low-bandgap Ag 2 S and wide-bandgap ZnS quantum dots (QDs). Ag 2 S QDs were synthesized with bead-chain-like structure by the self-assembly route and further covalently bound with ZnS QDs to be coated onto the indium tin oxide (ITO) electrodes. It was discovered that the ZnS@Ag 2 S-modified electrodes could display the visible-light-driven PEC behavior, of which Ag 2 S and ZnS QDs could act as the PEC sensitizer and Hg2+-recognition probe, respectively. More importantly, the photocurrent responses of the developed electrodes could be specifically turned on in the presence of Hg2+ under the visible-light irradiation, presumably due to that Hg2+ might conduct a Zn-to-Hg exchange on ZnS QDs to trigger the formation of HgS/ZnS@Ag 2 S heterojunction towards the enhanced electron-hole separation. The as-prepared PEC sensor could facilitate the detection of Hg2+ with concentrations ranging from 0.010–1000 nM, with a detection limit of about 1.0 pM. Besides, the feasibility of practical applications of the developed PEC analysis strategy was verified by probing Hg2+ in environmental water samples. Such a visible-light-driven PEC detection platform with the unique "turn-on" signal output may promise for the extensive applications for Hg2+ evaluation. [ABSTRACT FROM AUTHOR]

Background: Acceptance and commitment therapy (ACT) is an intervention focusing on altering how patients relate to their thoughts. This study aimed to investigate the effects of ACT on self-management ability and psychological resilience of young and middle-aged patients undergoing percutaneous transluminal coronary intervention (PCI) for primary myocardial infarction (MI).Methods: This pilot study included 98 young and middle-aged patients who underwent PCI for primary MI using a convenient sampling method. The patients were divided into a control group and an ACT group using the random number table method. The patients in the control group received routine nursing, while those in the ACT group received routine nursing combined with ACT.Results: The psychological resilience and self-management ability scores were significantly higher in the ACT group than in the control group 3 months after the intervention (P < 0.001 and < 0.05, respectively). In addition, compared to the baseline scores of psychological resilience and self-management ability, these scores were significantly higher in the ACT group at 3 months post-intervention (P < 0.001 and < 0.05, respectively).Conclusion: ACT could enhance the psychological resilience and self-efficacy and improve the self-management ability of young and middle-aged patients who underwent PCI for primary MI.Trial Registration: China Clinical Trial Center ChiCTR2000029775 . Registered on 13 February 2020. Registration title:Study on the popularization and application of rotational atherectomy for the treatment of severely calcified coronary lesions. [ABSTRACT FROM AUTHOR]

In this paper, based on the Hirota and Maxwell–Bloch (H‐MB) system and its application in the theory of the femtosecond pulse propagation through an erbium doped fiber, we define two kinds of nonlocal Hirota and Maxwell–Bloch (NH‐MB) systems, namely, PT‐symmetric NH‐MB system and reverse space‐time NH‐MB system. Then, we construct the Darboux transformations of these NH‐MB systems. Meanwhile, we derive the explicit solutions by the Darboux transformations. [ABSTRACT FROM AUTHOR]

With the development of the Internet, the types and quantities of malware have grown rapidly, and how to identify unknown malware is becoming a new challenge. The traditional malware detection method based on fixed features is becoming more and more difficult. In order to improve detection accuracy and efficiency for mobile terminals, this paper proposed a malware detection method for mobile terminals based on application programming interface (API) call sequence, which was characterized by the API call sequence and used a series of feature preprocessing techniques to remove redundant processing of the API call sequence. Finally, the recurrent neural network method (RNN) was used to build the model and perform detection and verification. Furthermore, this paper constructed a malware detection model based on a two-way recurrent neural network and used the two-way long short-term memory network model (LSTM) to train the data set containing 5986 malware samples and 5065 benign software samples to obtain the final detection model and its parameters. Finally, the feature vector of the APK file to be detected was passed into the model and obtained the detection results. The experimental results indicated that the detection accuracy of this method can reach 93.68%. [ABSTRACT FROM AUTHOR]

A photocatalyst of Ag 2 S/AgI-Bi 2 S 3 /BiOI was synthesized with Z -scheme heterojunctions simply by the S2−-I− anion exchange route showing broad visible light response and enhanced photogenerated carriers properties. The yielded Ag 2 S/AgI-Bi 2 S 3 /BiOI could feature the reactive active sites of Bi 2 S 3 /BiOI and Ag 2 S/AgI heterojunctions, serving as the photogenerated electron donors and photogenerated electron acceptors, respectively. Ag bridges were generated to ensure the construction of Z -scheme strategy, which further improved the migration direction of charge carriers in nanocomposites. Moreover, the analysis of photoluminescence spectra and electrochemical impedance spectroscopy could testified the functions of heterojunctions, which dramatically achieved the enhanced separation and transferring capacity of photogenerated electron-hole pairs in photocatalyst, respectively. In addition, Ag 2 S/AgI-Bi 2 S 3 /BiOI with large specific surface area facilitated the efficient photocatalytic removal of salicylic acid (SA) (up to 89.2%) under visible light. Favorable photocatalytic production of hydrogen peroxide (H 2 O 2) were obtained in pure water driven by the visible light. Besides, by the results of capture experiments, DMPO spin trapping ESR spectra and band structures analysis, the Z -scheme manner of the nanocomposites could promote the reduction ability of photo-generated electrons so as to produce numerous ·O 2 − during the photocatalytic reactions toward the photocatalytic SA removal and H 2 O 2 production. Ag 2 S/AgI-Bi 2 S 3 /BiOI with broad visible light response and enhanced photogenerated carriers properties performed efficient photocatalytic salicylic acid removal via Z-scheme strategy. Unlabelled Image • Ag 2 S/AgI-Bi 2 S 3 /BiOI is synthesized by the S2−-I− anion exchange at room temperature. • The yielded Bi 2 S 3 /BiOI and Ag 2 S/AgI serve as different functions for photocatalysis. • Z-scheme indicates high separation and transfer capacity of photogenerated carriers. • Ag 2 S/AgI-Bi 2 S 3 /BiOI exhibits powerful visible light harvest for the SA removal. • The efficiently generation of H 2 O 2 could be expected in water under visible light. [ABSTRACT FROM AUTHOR]

• Sr/Cu-HBGNs were successfully synthesized using a PAA-based template method firstly. • Incorporation of Sr/Cu reduced the size and enhanced the thermal stability of HBGNs. • Sr/Cu-HBGNs exhibited pH and temperature-responsive controlled release behavior. • Sr-HBGNs show potential as injectable and drug-loading biomaterials. Spherical materials with hollow cores have received tremendous attention since they possess extraordinary drug-loading capacity and sustained controllably release property. In this work, hollow bioactive glass nanospheres (HBGNs) through a novel and facile method employing polyacrylic acid (PAA) as the sacrificial template firstly were regulated by doping strontium/copper (Sr/Cu). The corresponding morphology, structure, physicochemical properties, and apatite-mineralization ability of Sr/Cu-doping HBGNs (Sr/Cu-HBGNs) have been thoroughly investigated. It was seen notably the loading efficiency of HBGNs, 5Sr-HBGNs rose from 4.97 ± 2.29%, 10.02 ± 2.93% to 84.94 ± 0.77%, 87.91 ± 0.23% after vancomycin hydrochloride (VAN) content increased, while that of 5Cu-HBGNs had negative impact from 2.14% ± 1.41% to 5.58 ± 2.55%. Meanwhile, they were pH and temperature sensitive. Thereby, Sr-HBGNs with excellent surface nature, biodegradability and biocompatibility can potentially be utilized as injectable and drug-loading biomaterials for in vitro tissue regeneration and drug control release. [ABSTRACT FROM AUTHOR]

A series of magnetic Ag/BiOI/ZnFe 2 O 4 hybrids synthesized via hydrothermal process, subsequent deposition-precipitation and photoreduction method were employed to remove elemental mercury (Hg 0 ) under fluorescent light irradiation. The effects of Ag content, fluorescent light irradiation, reaction temperature, pH value, flue gas composition, anions and photocatalyst dosage on Hg 0 removal were investigated in detail. The as-synthesized photocatalysts were characterized using N 2 adsorption-desorption, XRD, SEM, TEM, HRTEM, XPS, VSM, DRS, ESR, PL and photocurrent response. The results showed that the ternary Ag/BiOI/ZnFe 2 O 4 hybrids possessed enhanced visible-light-responsive photocatalytic performances for Hg 0 removal. Ag/BiOI/ZnFe 2 O 4 photocatalyst could be easily recovered from the reaction solution by an extra magnet and was stable in the process of Hg 0 removal. Lower content of Ag was highly dispersed on the surface of BiOI/ZnFe 2 O 4 , while higher content of Ag would result in some aggregations and/or the blockages of micropore. In comparison to BiOI/ZnFe 2 O 4 , Ag deposited BiOI/ZnFe 2 O 4 material showed lower recombination rate of electron–hole pairs. The superior Hg 0 oxidation removal could correspond to good match of BiOI and ZnFe 2 O 4 , excellent fluidity and surface plasmon resonance effect of Ag 0 nanoparticles, which led to higher separation efficiency of photogenerated electrons and holes, thereby enhancing the hybrids’ photocatalytic activity. [ABSTRACT FROM AUTHOR]

• Electrospun organic/inorganic VAN@5Sr/Cu-HBGNs/PEO/SF scaffolds were fabricated. • The hybrid scaffolds exhibited pH-responsive controlled release behavior. • VAN@5Sr-HBGNs/PEO/SF could prolong the drug release under neutral conditions. • Incorporation of 5Sr/Cu-HBGNs into scaffolds enhanced the corresponding bioactivity. Organic/inorganic hybrid biomaterials based on polymeric nano-composites constructed from mixture of biodegradable polymeric matrices and bioactive inorganic substrates have been highly attractive owing to their efficient tissue engineering applications. Herein we reported, for the first time, electrospun silk fibroin/polyethylene oxide (SF/PEO) scaffolds incorporated with appropriate strontium or copper-doped hollow bioactive glass nanospheres (Sr/Cu-HBGNs) loading with vancomycin hydrochloride (VAN) were prepared and their use as pH-sensitive drug nano-carriers to extend the duration of drug release were reported as well. In addition, the excellent apatite-formation ability of Sr/Cu-introduced nanocomposites improved the bioactivity of the related scaffolds. [ABSTRACT FROM AUTHOR]

In an attempt to solve the problems of the low intelligent distribution degree and high working intensity of auxiliary transportation systems in underground coal mines, an intelligent distribution strategy of materials in the whole mine is put forward. Firstly, combined with the characteristics of materials and standard containers, a three-dimensional loading model is established with the goal of maximizing the space utilization of standard containers, and a three-dimensional space segmentation heuristic algorithm is used to solve the material loading scheme. Then, the multi-objective optimization model of distribution parameters is established with the goal of the shortest delivery distance, the shortest delay time, and the fewest number of delivery vehicles, and the dual-layer genetic algorithm is used to solve the distribution scheme. Finally, the spatiotemporal conversion coefficient is designed to solve the task list by hierarchical clustering, and the solution time is reduced by 30%. The results show that the dual-layer genetic algorithm based on hierarchical clustering has good adaptability in complex material scheduling scenarios. [ABSTRACT FROM AUTHOR]

Bacterial infections and poor vascularization delay wound healing, thus necessitating alternative strategies for functional wound dressings. Zinc oxide (ZnO) has been shown to exert a potent antibacterial effect against bacterial species. Similarly, Glucagon-like peptide-1 (GLP-1) analogue liraglutide (LG) has been shown to promote vascularization and improve wound healing. The objective of this research was to investigate the synergistic effect of ZnO nanoparticles (ZnO-NPs) and LG to simultaneously induce antibacterial, hemostatic, and vascularization effects for infected wound healing. Electrospun poly (l -lactide-co-glycolide)/gelatin (PLGA/Gel) membranes containing ZnO-NPs and LG displayed good biocompatibility and hemostatic ability. Both, ZnO-NPs and LG exhibited synergistic antibacterial effect against Staphylococcus aureus and Escherichia coli as well as improved the migration and tubule-like network formation of human umbilical vein endothelial cells (HUVECs) in vitro. Once evaluated in a bacterial-infected wound model in rats, the membranes loaded with ZnO-NPs and LG effectively promoted wound healing causing significant reduction in wound area and scar-like tissue formation. Therefore, ZnO-NPs/LG synergism may offer an invaluable solution for the treatment of poorly healing infected wounds. [Display omitted] • Bacterial infected diabetic wounds are difficult to be healed, which require alternative solutions for their timely healing. • Functional dressings, which may simultaneously prevent bacterial infection and promote vascularization hold great promise. • Zinc oxide and Liraglutide synergistically improved hemostatic and antibacterial properties as well as the hemocompatibility. • Zinc oxide and Liraglutide containing dressings also promoted wound closure in vitro and in vivo and tube formation in vitro. [ABSTRACT FROM AUTHOR]

Background: Gastric cancer (GC) is common in East Asia, yet its molecular and pathogenic mechanisms remain unclear. Circular RNAs (circRNAs) are differentially expressed in GC and may be promising biomarkers. Here, we investigated the role and regulatory mechanism of circTMC5 in GC. Methods: CircTMC5 expression was detected in human GC and adjacent tissues using microarray assays and qRT-PCR, while the clinicopathological characteristics of patients with GC were used to assess its diagnostic and prognostic value. The circTMC5/miR-361-3p/RABL6 axis was examined in vitro and vivo, and the immune roles of RABL6 were evaluated using bioinformatics analyses and immunohistochemistry (IHC). Results: CircTMC5 was highly expressed in GC tissues, plasma, and cell lines, and was closely related to histological grade, pathological stage, and T classification in patients with GC. CircTMC5 expression was also an independent prognostic factor for GC and its combined detection with carcinoembryonic antigen may improve GC diagnosis. Low circTMC5 expression correlated with good prognosis, inhibited GC cell proliferation, and promoted apoptosis. Mechanistically, circTMC5 overexpression promoted GC cell proliferation, invasion, and metastasis but inhibited apoptosis by sponging miR-361-3p and up-regulating RABL6 in vitro and vivo, whereas miR-361-3p up-regulation had the opposite effects. RABL6 was highly expressed in GC and was involved in immune regulation and infiltration in GC. Conclusions: CircTMC5 promotes GC and sponges miR-361-3p to up-regulate RABL6 expression, thus may have diagnostic and prognostic value in GC. RABL6 also displays therapeutic promise due to its role in the immune regulation of GC. [ABSTRACT FROM AUTHOR]

This article models a hydro turbine based on the dynamic description of the hydraulic system having a surge tank and elastic water hammer. The dynamic of the hydraulic system is transformed from transfer function form into the differential equation model in relative value. This model is then combined with the motion equation of the main servomotor to form the nonlinear model of the hydro turbine, in which the power of the hydro turbine is calculated using algebraic equation. A new control model is thus proposed in which the dynamic of the surge tank is taken as an additional input of control items. As such, the complex hydraulic system is decomposed into a classical one penstock and one machine model with an additional input control. Therefore, the order of the system is descended. As a result, the feasibility of the system is largely improved. The simulated results show that the additional input of the surge tank is effective and the proposed method is realizable. [ABSTRACT FROM PUBLISHER]

Abstract: A double shell-potential flow model is developed to study the free vibration of single-walled carbon nanotube (SWCNT) conveying water. Water is divided into the absorbed layer of water molecules and the water flow in the center of the SWCNT. The SWCNT and the internally absorbed layer of water are modelled as two-layer thin shells coupled via the interlayer van der Waals (vdW) interaction. It is shown that the vdW interaction is responsible for an upshift in the frequency of the SWCNT and an improvement of the system stability. Results also reveal that the internal moving water plays an important role in the instability of system whereas it has very little influence on the dynamic characteristics of the SWCNT. It is hoped that the paper can provide a new and efficient approach for the study of the general dynamic behavior of fluid-filled nanodevices. [Copyright &y& Elsevier]

Abstract: The aim of this paper is to show how the concept of nonlinear normal modes (NNMs) can be used to characterize the nonlinear dynamical behaviors of double-walled carbon nanotubes (DWCNTs). DWCNTs are modeled as double simply supported elastic beams with van der Waals (vdW) forces between the inner and outer walls. The multiscale method for deriving the approximate solutions of NNMs is applicable to the nonlinear systems. According to the procedure, the typical features – coaxial and noncoaxial vibrations of the system are exhibited in the literature. Moreover, the case of 1:3 internal resonance is discussed in detail, which can give rise to much more complex phenomenon for DWCNTs systems. Meanwhile, the amplitude-time curves of the nonlinear vibration with different initial conditions are presented, and the amplitude-frequency characteristic curves of the nonlinear vibration are also obtained. [ABSTRACT FROM AUTHOR]

Abstract: The traveling wave solutions of the generalized nonlinear derivative Schrödinger equation and the high-order dispersive nonlinear Schrödinger equation are studied by using the approach of dynamical systems and the theory of bifurcations. With the aid of Maple, all bifurcations and phase portraits in the parametric space are obtained. All possible explicit parametric representations of the bounded traveling wave solutions (solitary wave solutions, kink and anti-kink wave solutions and periodic wave solutions) are given. [ABSTRACT FROM AUTHOR]

The nonlinear dynamical behaviors of single-walled carbon nanotubes (SWCNTs) with the initial axial stress are investigated based on Donnell's cylindrical shell model. By using the bifurcation theory of dynamical systems on a vibration equation of SWCNTs, the existence of centers, saddles, families of periodic orbits, homoclinic orbits and/or heteroclinic orbits is shown. Under different initial conditions, various sufficient conditions to guarantee the existence of the above solutions are given and the dynamical behaviors of SWCNTs are well-known. [ABSTRACT FROM AUTHOR]

Abstract: The Hangzhou Bay faces frequent threats from typhoon-induced storm surge and has attracted considerable attentions of coastal researchers and environmental workers. A three-dimensional storm surge model system based on Finite-Volume Coastal Ocean Model (FVCOM) and analytical cyclone model is applied to investigate the hydrodynamic response in the Hangzhou Bay to tropical typhoon. This model has been used to reproduce the storm surge generated by Typhoon Agnes (No. 8114) and the simulated wind field and water elevations have been compared with the available field observations. A series of numerical experimental cases have been conducted to study the effects of land reclamation project (shoreline relocation and seabed deformation) and cyclonic parameters (minimal central pressure (MCP), radius to maximal wind (RMW) and translation speed (TS)) on the hydrodynamics in the Hangzhou Bay. The results show that the shoreline relocation and seabed deformation could generate much higher storm surge in the vicinity of reclamation project with the shoreline relocation making main contribution (about 70%) to this increase. It is found that among the cyclonic parameters, RMW is the most important factor affecting the peak surge in the Hangzhou Bay. [Copyright &y& Elsevier]

Gastric cancer (GC) is the fifth most common cancer and GC has a high mortality rate worldwide. Circular (circ) RNAs serve an important role in cancer. The present study aimed to investigate the expression level of hsa_circ_0060975 in gastric cancer (GC) and to determine the clinical pathological significance of hsa_circ_0060975 in patients with GC. Reverse transcription-quantitative PCR was used to detect expression level of hsa_circ_0060975 in 192 GC and adjacent non-cancerous gastric tissues, in GC cell lines (MKN-45, HGC27 and AGS) and a human gastric epithelium cell line (GES-1), as well as in plasma samples from 126 patients with GC and 92 healthy volunteers. All plasma and tissue samples of were obtained from The First Affiliated Hospital of Anhui Medical University (Hefei, China). The relationship between hsa_circ_0060975 expression and clinical pathological factors was analyzed using the χ2 test. The diagnostic value of hsa_circ_0060975 was analyzed using the receiver operating characteristic curve (ROC curve), while the Kaplan-Meier method was used to analyze the relationship of hsa_circ_0060975 expression with the survival of patients with GC as determined by log-rank tests. Univariate and multivariate Cox regression analyses were used to identify the prognostic factors, including hsa_circ_0060975 expression and clinical pathological factors. In addition, the potential function of hsa_circ_0060975 was evaluated via bioinformatics analysis. The expression level of hsa_circ_0060975 was higher in GC tissues compared with adjacent non-cancerous gastric tissues, GC cell lines compared with GES-1 and plasma samples from patients with GC compared with plasma samples from healthy volunteers. In addition, higher hsa_circ_0060975 expression was associated with histological grade, pathological stage and tumor (T) classification in GC tissues and plasma samples (P<0.05). The area under the ROC curves of hsa_circ_0060975, the combination with hsa_circ_0060975 and carcinoembryonic antigen (CEA) or CEA alone were 0.804 (sensitivity, 0.746; specificity, 0.783; P<0.001); 0.931 (sensitivity, 0.937; specificity, 0.870; P<0.001) and 0.924 (sensitivity, 0.937; sspecificity, 0.804; P<0.001) respectively. The Kaplan-Meier survival analysis revealed that the overall survival (OS) and disease-free survival (DFS) time of patients with higher hsa_circ_0060975 expression were shorter compared with those in patients with lower hsa_circ_0060975 expression. Univariate and multivariate Cox regression analyses in OS and DFS time determined that the expression level of hsa_circ_0060975, histological grade and pathological stage were independent prognostic factors for patients with GC. In addition, the bioinformatics analysis results suggested that the abnormal expression of hsa_circ_0060975 may serve an important role in tumorigenesis. Hence, hsa_circ_0060975 expression may be an independent prognostic factor for patients with GC and may be a potential marker for biological malignancy. [ABSTRACT FROM AUTHOR]

Solidification and remelting of aluminum though alumina preform under a centrifugal force field were modeled numerically. Transient solidification and remelting phenomena appear on the infiltration front in three distinct regions: the remelting region, the solid–liquid congruent melting region and the uninfiltrated region. The regional extent of solidified metal and its solid volume fraction increase with the moving of the infiltration front. The speeds of the infiltration and remelting fronts decrease with decreasing porosity and rotational frequency. [Copyright &y& Elsevier]

This paper is concerned with vibration analysis considering fluid–structure interaction (FSI) in liquid-filled pipe system using transfer matrix method (TMM) in frequency domain. The emphasis is placing specially upon the multi-span pipe system with middle rigid constraints. Three major mechanisms of coupling, the friction coupling, the Poisson coupling and the junction coupling, as well as both distributed and concentrated external excitations are considered in this study. A phenomenon associated with the rigid constraints, namely, a junction coupling depending on the Poisson coupling and friction coupling (might be called the conditional junction coupling), is revealed and discussed. Numerical examples indicate that the conditional junction coupling has much larger influence on the frequencies of a liquid-filled pipe system than the Poisson coupling does. It is also shown through the numerical examples that the proposed method is efficient. [Copyright &y& Elsevier]

This paper is concerned with the vibration analysis of a liquid-filled pipe system, which extends the frequency domain analysis of the fluid–structure interaction from single pipe to a pipe system with multi-pipe sections using transfer matrix method. Taking into account all the three major coupling mechanisms, namely the friction coupling, Poisson coupling and junction coupling, the proposed method can be used to analyze the free vibration and the forced vibration of a pipe system with multi-pipe sections subjected to various kinds of external excitations. The transform matrix, impedance matrix and frequency equation in frequency domain are also presented and discussed. Numerical examples are presented to illustrate the application of the proposed method, which shows how the natural frequencies and mode shapes change with the radius and materials of the pipe system. [Copyright &y& Elsevier]

[Display omitted] • VEGF-binding peptide "BP" and OEO were loaded into PLGA/Gelatin fibers. • OEO improved anti-inflammatory, anti-oxidative, and anti-bacterial properties. • The BP containing fibers effectively accelerated angiogenesis. • BP and OEO co-loaded fibers showed rapid repair of infected wounds. • Combined delivery of BP and OEO also suppress bacterial growth in vivo. Skin regeneration is hindered by poor vascularization, bacterial infection, prolonged inflammation, and oxidative wound microenvironment, which necessitate the fabrication of alternative wound dressings with anti-adhesion, anti-infection, and angiogenic functions. Prominin-1-derived peptide (PR1P, herein named as BP) may sequester vascular endothelial growth factor (VEGF) by interacting with VEGF receptors and promote wound healing. Oregano essential oil (OEO, herein named as O), is a natural plant extract mainly containing carvacrol and thymol, which manifests low cytotoxicity and cost-effectiveness as well as anti-inflammatory, antibacterial, and anti-oxidative properties. Herein, we fabricated anti-adhesion, anti-infection, and angiogenic wound dressings by simultaneously exploiting BP and O in electrospun poly(L-lactide-co-glycolide)/gelatin (PG)-based fibrous dressings. Different types of in vitro assays manifested anti-inflammatory, anti-oxidative, anti-bacterial, and angiogenic characteristics of dressings. The PG@BPO dressings further enabled good wound healing 14 days post-implantation alongside anti-adhesion, and anti-infection properties. The tensile strength of the repaired skin was almost similar to the normal skin (repaired skin, 1.70 MPa and normal skin, 1.78 MPa). These multifunctional dressings may hold great promise for skin repair and related disciplines. [ABSTRACT FROM AUTHOR]

A capillary-based fluorimetric analysis method was developed for probing glucose (Glu) in blood using Glu oxidase-anchored gold nanoclusters (GOD–AuNCs) and the ZIF-8 matrix. AuNCs were attached with GOD to be further encapsulated into the ZIF-8 matrix through the protein-mediated formation route. The resulting GOD–AuNCs@ZIF-8 nanocomposites could present the AuNC-improved catalysis of GOD and ZIF-8-improved environmental stability. The ZIF-8-enhanced fluorescence intensity of AuNCs could also be expected. Moreover, a capillary-based fluorometric platform was constructed for sensing Glu by coating the capillaries first with GOD–AuNCs and then the ZIF-8 matrix. Herein, Glu was introduced through the self-driven sampling to trigger the GOD-catalyzed production of hydrogen peroxide, which could induce the fluorescence quenching rationally depending on the Glu concentrations. The developed fluorimetric method could allow for the rapid and simple detection of Glu with the concentrations linearly ranging from 5.0 μM to 2.5 mM. Besides, the feasibility of practical applications was demonstrated by the evaluation of Glu in blood showing the recoveries of 96.2%–103.4%. Importantly, the proposed design of the capillary-based fluorimetric platform by the synergetic combination of catalysis-specific recognition and fluorescence signaling may open a new door toward extensive applications in the biological sensing, catalysis, and imaging fields. [ABSTRACT FROM AUTHOR]

Conventional methods that involve an increase in pressure are used to improve the solubility and yield of Mg in the steelmaking. Under high pressure, the effect of Mg addition on the number, morphological characteristics, composition, size, and density of inclusions in Cr12Mo1V1 steel (C: 1.40–1.60 wt%, Si: ≤0.60 wt%, Mn: ≤0.60 wt%, S: ≤0.03 wt%, P: ≤0.03 wt%, Cr: 11.00–13.00 wt%, V: ≤1.00 wt%, and Mo: 0.70–1.20 wt%) is studied. The experiments are made under three contents of Mg: 0, 0.0012 wt% and 0.0041 wt%. Results show that Al 2 O 3 and MnS inclusions transform into approximately spherical MgO·Al 2 O 3 spinel and spherical MgO·MgS inclusions, respectively. At ~0.07 wt% dissolved aluminum content, the micro content of Mg in molten steel leads to the formation of MgO·Al 2 O 3 spinel inclusions. The MgO·Al 2 O 3 inclusions disappear completely when the mass fraction of Mg is larger than 39.734 × 10−6. Further, as the Mg content increases, the number of inclusions <1 μm increases, whereas the number of inclusions >2 μm decreases. Meanwhile, during molten steel solidification, MnS and MnS–MgS precipitate around MgO·Al 2 O 3 and MgO inclusions, respectively. The densities of MgO·Al 2 O 3 spinel inclusions are lower than those of alumina inclusions. As the Mg content in Mg-containing inclusions increases, the density of inclusions decreases, leading to an improvement in inclusion removal efficiency. The role of Mg in the mechanical properties, tensile fracture morphology, and inclusions of quenched and tempered Cr12Mo1V1 steel is also investigated. As the Mg content increases from 0 wt% to 0.0041 wt%, at the tensile fracture, the area of shear lip goes through a process from small to large, the dimples go through a process from generation to deepening, and the strength and plasticity correspondingly increase. [ABSTRACT FROM AUTHOR]

An urchin-like LaPO 4 -based nanocomposite integrating Ag 3 PO 4 and Pd has been initially synthesized via a controllable self-assembly route, with enhanced photocatalysis and ultrastable structure for the synergistic hydrogen (H 2) evolution under sunlight. Citric acid was employed as a structure-mediated agent to guide the oriented growth of LaPO 4 along [101] facet at room temperature, showing the urchin-like 3D structure. Furthermore, Pd and Ag 3 PO 4 were coated in turn resulting in the Ag 3 PO 4 /Pd/LaPO 4 nanocomposite, in which Pd and Ag 3 PO 4 could act as the functions of electron receptor and electron donor in the photocatalysis, respectively. It was discovered that the as-developed nanocomposite could present the robust photocatalysis and stable morphology after consecutive uses. Based on the band structure analysis, a Z -scheme system of Ag 3 PO 4 /Pd/LaPO 4 was thereby proposed for the sunlight photocatalysis, as testified by DMPO spin trapping ESR spectra. Also, the photoluminescence and electrochemical impedance of nanocomposites were conducted, indicating that the improved carriers properties should be responsible mainly for the dramatically enhanced photocatalytic activities. Moreover, the outstanding photocatalytic performances of Ag 3 PO 4 /Pd/LaPO 4 were demonstrated in H 2 evolution (1084.3 μmol·g−1·h−1) under sunlight. Importantly, such a citric acid-controlled self-assembly route may pave the way toward the fabrication of multi-component photocatalyst tailored for the wide photocatalytic applications. Ag 3 PO 4 /Pd/LaPO 4 with strong synergistic effects and optimized photogenerated carriers properties performed efficient photocatalytic H 2 evolution via Z-scheme strategy. Unlabelled Image • A new Ag 3 PO 4 -Pd/LaPO 4 photocatalyst is synthesized with urchin-like 3D structure. • Pd and Ag 3 PO 4 increase the synergistic photocatalysis efficiency of nanocomposite. • Strong steric hindrance ensures a highly morphological and photocatalysis stability. • Z-scheme indicates high separation and transfer capacity of photogenerated carriers. • Ag 3 PO 4 -Pd/LaPO 4 shows outstanding photocatalytic hydrogen evolution activity. [ABSTRACT FROM AUTHOR]

Carbon nitride quantum dots (CNQDs) were doped into melamine (MA) and silver (Ag) matrix yielding CNQDs@MA−Ag nanocomposites by the supramolecular self‐assembly route. To our surprise, the resulting mesoporous nanocomposites could present different morphologies (i. e., nanowires, nanoflowers, and nanosheets) and especially tunable visible‐light photocatalysis performances depending on the percentages of CNQDs used. It was discovered that the CNQDs@MA−Ag ones with the pinecone‐like structure (containing 30 % CNQDs) could exhibit the strongest visible‐light photocatalysis for splitting water to yield H2O2 with a production efficiency of 39.82 μmol ⋅ g−1 h−1, which is more than ten‐fold higher than that of CNQDs alone. Herein, the nano‐scaled Ag could facilitate the increased light harvesting and the separation as well as transmission of electron‐hole pairs of CNQDs resulting in the enhanced visible‐light photocatalysis of nanocomposites. More importantly, the pinecone‐like ones might additionally enable more exposed active sites of photocatalysis and larger mesoporous specific area of contacting dissolved oxygen in water, leading to the higher photocatalytic efficiency of H2O2 generation. This CNQDs‐based fabrication strategy may open a new door towards the design of a variety of photocatalysts with different morphologies and tunable photocatalysis performances for the efficient splitting water toward H2O2 evolution under sunlight. [ABSTRACT FROM AUTHOR]

Abstract The combination of biodegradable polymers and bioactive inorganic materials is a promising method to mimic native tissue in bone regeneration. Toward this direction, electrospun fibrous scaffolds were successfully fabricated in the silk fibroin (SF) matrix containing new bioceramics on the basis of mesoporous bioactive glass/hydroxyapatite nanocomposite (MGHA). The physicochemical properties and surface hydrophilicity of these biphasic composite could be tailored by the addition of MGHA content. The increase in surface hydrophilicity and bioactivity of the as-spun composite fibers were observed with the increasing the nanoparticle contents while decreasing their tensile strength. In vitro cytotoxicity evaluation based on human bone marrow-derived mesenchymal stem cells (hMSCs) revealed that a positive osteogenic differentiation effect on SF/MGHA7 sample as evidenced by an increased alkaline phosphatase (ALP) activity, and upregulated osteoblastic gene expression compared with SF samples. These findings supported the suitability of the SF/MGHA composite system for its potential application in cell–material combination in bone tissue engineering. Graphical abstract Unlabelled Image Highlights • An organic-inorganic electrospun fibrous scaffold was fabricated by the combination of SF and MGHA. • The MGHA addition increased the surface hydrophilicity and bioactivity whereas decreasing the tensile strength. • The obtained membrane promoted hMSCs adhesion and proliferation. [ABSTRACT FROM AUTHOR]

This study investigated the effects of fermentation with kefir grains on the nutritional composition, flavor, and physical stability of hemp seed, and explored its potential as a probiotic plant-based beverage. After fermentation of a homogenized hemp seed water suspension, the concentrations of organic acids (lactic, acetic, tartaric, butyric, succinic, and malic acids) increased. The content of nutritional components, amino acids, and free fatty acids increased, as well as the number (from 16 to 21) and concentrations of flavor compounds, such as alcohols, acids, and esters. Fermentation also increased the particle size, viscosity, and phase-separation resistance of the final product. Therefore, kefir grains improved the nutritional composition, flavor, and physical stability of the hemp seed beverage, indicating its potential as a functional beverage, and providing a theoretical basis for the development of plant-based fermented beverages. • Kefir grain endow that hemp seed with more organic acid. • Kefir grains improve nutrient component of fatty acid and amino acid in hemp seed. • Kefir grains fermentation gives more flavor to the hemp seed. • Kefir grains fermentation can increase the viscosity and stability of hemp seed. [ABSTRACT FROM AUTHOR]

To explore the possibility of using surface coating to reduce environmental stress cracking (ESC) of transparent polycarbonate (PC) parts, silicone coated and SiO 2 coated PC were tested in a self-made three-point bending apparatus in the presence of ethanol. The variation of stress with time was recorded, and the surface cracking was observed to evaluate the ESC resistance of samples. Slower stress relaxation rates and fewer surface cracks indicated that silicone coating improved the ESC resistance of PC, but SiO 2 coated PC was found to be no better than that of uncoated PC. Silicone coating reduced the absorption of ethanol in PC, weakening the surface plasticization, thus hindering the formation and development of cracks in PC. Nanoindentation test results showed that the mechanical properties such as hardness and elastic modulus of silicone coating are a better match for PC than SiO 2 coating. This allows the silicone coating to have a favorable effect in providing continuous protection for PC under the combined action of ethanol and stress. [ABSTRACT FROM AUTHOR]

Hollow nanospherical bioactive glasses were conducted though sol–gel process using poly(acrylic acid) (PAA) as the template. The incorporation of PAA was to form the core after air combustion, whereas the inorganic shell was produced by glass precursor. The mixture of different tetraorthosilicate (TEOS)/PAA contents into a glass network tailored the shell thickness, morphological, and structural properties of HBGs. The in vitro bioactivity evaluation confirmed that HBG2 sample exhibited good apatite formation ability, thereby denoting that the proposed method enhanced the potential application of HBGs in bone tissue regeneration and drug delivery. [ABSTRACT FROM AUTHOR]

In this paper, we study a dynamic fluid–structure interaction (FSI) model for an elastic structure immersed and spinning in the fluid. To describe the motion of a rotating elastic structure, we develop a linear constitutive model, that is suitable for the application of the arbitrary Lagrangian–Eulerian (ALE) method in FSI simulations. Additionally, a new ALE mapping method is designed to generate the moving fluid mesh while the deformable structure spins in a non-axisymmetric fluid channel. The structure velocity is adopted as the principle unknown to form a monolithic saddle-point system together with fluid velocity and pressure. Using the mixed finite element method and Newton’s linearization, we discretize the nonlinear saddle-point system, and prove that the discrete saddle-point system is well-posed. The developed methodology is applied to a self-defined elastic structure and a realistic hydro-turbine under a prescribed angular velocity. Numerical validation is also conducted to demonstrate the accuracy of the models and the numerical methods. [ABSTRACT FROM AUTHOR]

• Fe 3 O 4 QDs can present higher peroxidase-like catalysis than Fe 3 O 4 NPs. • Enhanced catalysis can be achieved for Fe 3 O 4 QDs if coated with sodium alginate. • Fe 3 O 4 QDs were coated onto capillary tubes by SA with film-forming capacity. • Automatic fetching of multiple samples can be expected by the capillarity power. • Capillary array-based colorimetric platform enables high-throughput detection of H 2 O 2. A simple and high-throughput colorimetric analysis array has been constructed for quantifying H 2 O 2 in milk using Fe 3 O 4 quantum dots (QDs), which were coated with sodium alginate (SA) and chromogenic substrate onto the arrayed capillary tubes. It was discovered that the Fe 3 O 4 QDs could present larger peroxidase-like catalysis than Fe 3 O 4 nanoparticles (NPs). Particularly, dramatically enhanced catalysis activity could be achieved for Fe 3 O 4 QDs if coated with SA films. Moreover, the use of SA could protect Fe 3 O 4 QDs to expect the improved environmental stability. A capillary arrays-based high-throughput colorimetric platform was thereby developed for the detection of H 2 O 2 in milk, with levels linearly ranging from 10 to 400 μM. Importantly, the developed colorimetric platform with the capillarity power for automatic fetching of multiple samples may promise the practical applications for extensive monitoring of multiple H 2 O 2 samples for food safety. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents the results from laboratory experiments to investigate the protection of scour around submarine pipelines under unidirectional flow using a rubber plate placed underneath the pipes. The pressure difference on the two sides of the pipeline is the driving force to initiate the movement of sediment particles and can be obtained by force balance analysis. Experiments covering a wide range of incoming flow velocity, pipe diameter and plate length show that there exists a critical pressure difference over which the movement of sediment and, thus, scour takes place. Analysis of the experimental results demonstrates that this critical pressure difference is related to the pressure difference of the axial points between upstream and downstream of the pipe, which can be easily determined. This critical pressure difference is used to develop an empirical formula for estimating the critical length of the rubber plate, over which the sediment movement and scour will not take place. Good agreement between the experiments and calculated critical plate length using the proposed formula is obtained. [Copyright &y& Elsevier]

Highlights: [•] We improve a 2D RNG k–ε sediment model including the effect of secondary currents. [•] We develop an efficient semi-coupled scheme to solve sediment models numerically. [•] Bed deformation induced by transport of non-uniform suspended and non-uniform bedload sediments is investigated. [•] The variation of effective bed material granularity has been examined. [ABSTRACT FROM AUTHOR]

Abstract: In order to remove perchlorate from water via adsorption, three modified inorganic-bentonites, such as hydroxy-aluminum pillared bentonite (Al-Bent), hydroxy-iron pillared bentonite (Fe-Bent), and mixed hydroxy-iron–aluminum pillared bentonite (Fe–Al-Bent), were synthesized and characterized. Bench-scale batch experiments were performed to study mechanisms behind the adsorption phenomenon and explore the factors affecting the perchlorate adsorption on pillared bentonites. The significant increase of interlayer spacing, BET surface area and total pore volume suggested a larger amount of active adsorption sites of the pillared bentonites surface and a wider perchlorate channel from the surface to the inner adsorption sites of bentonites, respectively. The results during adsorption process represented that the adsorption capacity of perchlorate followed the order: Fe-Bent>Fe–Al-Bent>Al-Bent. The perchlorate uptake on these three modified bentonites from 0.1mmol/L solution rapidly attained equilibrium within 100min. Pseudo-second-order kinetic model could provide satisfactory fitting of the kinetic data (R 2 >0.99). The Langmuir model fitted the adsorption isotherm very well (R 2 >0.98). The thermodynamic analysis indicated that the adsorption process was endothermic and spontaneous in nature. The pH changes appeared to have a little impact on the perchlorate adsorption performance using the Fe-Bent. While perchlorate removal by Al-Bent and Fe–Al-Bent decreased significantly with the increase of pH. Co-existing anions tests showed that the order of anion influence of the adsorption amount of on pillared bentonite was . The present study confirmed that inorganic-pillared bentonites would be one of candidates for perchlorate adsorbent. [Copyright &y& Elsevier]

Abstract: Various aggregates, such as spherical and elongated micelles, tubular and rodlike aggregates, as well as vesicles, are induced by adding sodium 2-naphthalenesulfonate (SNphs) or sodium benzenesulfonate (SBzs) into the aqueous solution of a gemini surfactant C12C2C12(Me) (1,2-ethanediyl-bis-(dodecyldimethylammonium bromide)). The aggregate morphology strongly depends on the added amount of the organic salts. Among the various aggregates, the elongated micelle and the tubular aggregate have larger solubilizing capacities than those with the other morphologies. However, SNphs and SBzs cannot induce similar aggregate transitions for the systems of C12C s C12(Me) (s =6, 8, 12). The possible mechanism of these phenomena is proposed based on the results of UV spectra and 1H NMR measurements and the molecular packing geometry rule. [Copyright &y& Elsevier]

Abstract: An investigation was made to determine the effect of water quenching process on microstructure and tensile properties of cold rolled dual-phase (DP) steel (0.06C–0.20Si–1.30Mn). Correlations of microstructure, tensile properties, and water quenching parameters were established. Analysis of optical and transmission electron microscopy shows that the microstructures are mainly composed of ferrite and martensite phases. The fraction of martensite covers from 20% to 68.36% in this study, which plays a key role on tensile properties. A small amount of retained austenite or bainite can also be found for different water quenching processes. It is observed that water quenching process can improve the DP steel grade of 450MPa up to 600MPa and still keep good ductility. Further, the ultimate tensile strength can even be improved above to 1000MPa under some water quenching processes. [Copyright &y& Elsevier]

Results of a numerical simulation investigating the complicated flushing process of an isolated trapped volume of salt water from a bar-blocked estuary are presented. A multiphase model, a part of the commercial code FLUENT 6.2, is applied. The governing equations together with initial and boundary conditions and the numerical scheme are described. The time-dependent salt-wedge position, vertical-density distribution, and proportion of total input kinetic energy converted into potential energy are examined for various incoming flow densimetric Froude number and estuary bed slope. The vertical position and thickness of the interfacial mixed layer between freshwater and salt water as well as the local gradient Richardson number are determined from simulated density profiles and velocity fields. The good agreement between the simulated and measured results indicates that the numerical model can be successfully applied to investigate the complex flushing process involving stratified flow. [ABSTRACT FROM AUTHOR]

Abstract: Riveting is a procedure widely used for fitting together two or more elements of a structure, that could be of the same or different material. In these assemblies the stress field is complex and a number of parameters, including effect of the geometrical discontinuities, contact between elements, tightening, material properties and applied load must be considered. The current work focuses on the study of fretting fatigue crack formation in common 6XXX aluminum alloys, used in land transportation equipments, and the determination of the characteristic crack initiation sites by means of both experimental and numerical methods. Three-dimensional finite element models were validated by the experimental results obtained with strain gauges. The influence of the contact friction coefficient at the fretting surface, and fastening forces, on the initiation of cracks, are discussed by the comparison of the different numerical results. [Copyright &y& Elsevier]

Correction for 'A capillary-based fluorimetric platform for the evaluation of glucose in blood using gold nanoclusters and glucose oxidase in the ZIF-8 matrix' by Luping Feng et al., Analyst, 2020, 145, 5273–5279, DOI: 10.1039/D0AN01090A. [ABSTRACT FROM AUTHOR]

The purpose of this research is to study the influence of aspect ratio and end conditions on the strength and failure mode of remolded soil samples in unconfined compressive strength tests. The digital image correlation method is used in this research to obtain the evolution process of the horizontal displacement field in remolded soil samples and analyze the deformation and failure characteristics in various sample sizes. Two-dimensional discrete element models of the soil samples are established to simulate the impact of different end-frictional conditions on stress-strain processes of samples. Results show that, with the growth of aspect ratios, the failure of samples transforms from tensile mode to shear mode, and the defects in the middle of samples become more obvious. Characteristic values of earthen sites' soil, such as peak strain, elastic modulus, and residual stress, change with various aspect ratios. The simulation results are in accordance with typical experiments, thus verifying the rationality of established discrete element models. By comparing the particle displacement directions and the respective proportions, the constraint caused by loading plate on samples is proved to be one of the reasons for the size effect. When the aspect ratio is higher than 1.0, the size effect disappears in end-frictionless samples. The research has practical significance to deepen understanding of the mechanism for unconfined compressive strength of site soil samples and provides scientific references for protection and reinforcement of earthen sites. [ABSTRACT FROM AUTHOR]