BackgroundThis study aims to accelerate revision surgery and treatment using X-ray imaging and deep learning to identify shoulder implant manufacturers in *** feature engineering approach based on principal component ...
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BackgroundThis study aims to accelerate revision surgery and treatment using X-ray imaging and deep learning to identify shoulder implant manufacturers in *** feature engineering approach based on principal component analysis and a k-means algorithm was used to cluster shoulder implant data. In addition, a pre-trained DenseNet201 combined with a capsule network (DenseNet201-Caps) shoulder implant classification model was ***201-Caps was the most effective classification model on the clustered dataset with an accuracy of 94.25% and an F1 score of 96.30%. Notably, clustering the dataset in advance improved the accuracy and the Caps implementations successfully enhanced the performance of all convolutional neural network models. The analysed results indicate that DenseNet201-Caps struggled to distinguish between the Cofield and Depuy manufacturers. Hence, a multistage classification approach was developed with an improved accuracy of 96.55% *** DenseNet201-Caps method enables the accurate identification of shoulder implant manufacturers.
River sand is an essential component used as a fine aggregate in mortar and *** to unrestrained exploitation,river sand resources are gradually being *** requires alternative *** study deals with the properties of cem...
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River sand is an essential component used as a fine aggregate in mortar and *** to unrestrained exploitation,river sand resources are gradually being *** requires alternative *** study deals with the properties of cement mortar containing different levels of manufactured sand(MS)based on quartzite,used to replace river *** river sand was replaced at 20%,40%,60%and 80%with MS(by weight or volume).The mechanical properties,transfer properties,and microstructure were examined and compared to a control group to study the impact of the replacement *** results indicate that the compressive strength can be improved by increasing such a *** strength was improved by 35.1%and 45.5%over that of the control mortar at replacement levels of 60%and 80%,*** there was a weak link between porosity and gas permeability in the mortars with manufactured sand,the gas permeability decreased with growing the replacement *** microstructure of the MS mortar was denser,and the cement paste had fewer microcracks with increasing the replacement level.
A simply and effective method, smoothed state-based peridynamics, is proposed to simulate the large deformation and fracture behaviors of general compressible hyperelasticity. The proposed method is developed from the...
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A simply and effective method, smoothed state-based peridynamics, is proposed to simulate the large deformation and fracture behaviors of general compressible hyperelasticity. The proposed method is developed from the state-based peridynamics, which can be defined directly from the given classical model by a corresponding deformation gradient. The handling way of modelling general hyperelastic material through the proposed method is described detailedly in this paper. The compressible Neo-Hookean model, density solution and other numerical technology are investigated. Some popular benchmark problems of hyperelasticity are solved successfully, including the Inflation of a hollow spherical ball, compressed cuboid, pinched cylinder and the elastomer fracture problems.
Surface-enhanced Raman spectroscopy (SERS) is closely related to the SERS substrate. SERS substrate should not only possess small gaps to generate strongly enhanced hot spots but also facilitate the entry of target mo...
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Surface-enhanced Raman spectroscopy (SERS) is closely related to the SERS substrate. SERS substrate should not only possess small gaps to generate strongly enhanced hot spots but also facilitate the entry of target molecules into these hot spots. However, the presence of ligands on the substrate can create steric hindrance, potentially impeding the access of target molecules to hot spots. In this study, we assembled a dense gold nanorod (AuNR) cluster with gaps of similar to 1 nm, utilizing laser-driven plasmonic bubbles. The AuNR cluster through laser-driven plasmonic bubbles was accompanied by the reduction of the ligands. The AuNR cluster can detect crystal violet solutions at concentrations as low as 10(-12) M and allows for the SERS identification of various molecules. Furthermore, the practical potential of this AuNR cluster was demonstrated by the detection of 10 ppb of paraquat on the tomatoes in situ. This work provides new insights into the assembly of laser-driven plasmonic bubbles with noble metal nanoparticles and their application in the field of SERS.
In the context of our rapidly digitizing society, computational thinking stands out as an essential attribute for cultivating aptitude and expertise. Through the prism of computational thinking, learners are more adep...
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In the context of our rapidly digitizing society, computational thinking stands out as an essential attribute for cultivating aptitude and expertise. Through the prism of computational thinking, learners are more adeptly positioned to dissect and navigate real-world challenges, poising them effectively to meet the exigencies of future societal landscapes. The paradigm of project-based learning, heralded as a potent educational methodology, significantly amplifies students' prowess in computational thinking. To delineate the nuanced interplay between project-based learning and its augmentation of computational thinking, we engaged in meta-analytical investigations, synthesizing outcomes from 31 distinct external experimental and quasi-experimental studies. Our analytical journey underscored that project-based learning markedly elevates students' competencies across five critical spectra: innovation, collaboration, critical analysis, algorithmic cognition, and problem resolution. Dissecting its impact across the K12 continuum reveals that primary students predominantly hone their collaborative acumen;middle-grade learners witness a pronounced ascent in creativity, critical, and algorithmic faculties, while the apex of high school education primarily sharpens critical analytical prowess. Thus, educators sculpting the contours of project-based learning should be calibrate their strategies, ensuring they resonate with the developmental and age-specific nuances of their audience, to fully unleash its latent potential in nurturing computational thinking.
A novel nonlocal thermo-hydro-mechanical coupling model is proposed to investigate cracking behaviors of quasi-brittle materials in the framework of advanced general particle dynamics (GPD). The nonlocal thermal condu...
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A novel nonlocal thermo-hydro-mechanical coupling model is proposed to investigate cracking behaviors of quasi-brittle materials in the framework of advanced general particle dynamics (GPD). The nonlocal thermal conduction equation and the nonlocal flow diffusion equation are derived based on nonlocal vector calculus and the microscopic constitutive equation. Moreover, the coupling influences are considered based on the nonlocal equation and the coupling principle. The governing equation of the coupling system is established in the framework of GPD. The correctness of the proposed model is verified through comparing with the corresponding experimental data, and the numerical results are in good agreement with experimental results. Finally, the proposed model is applied to analyze the deformation and cracking behaviors of rock mass around tunnels, and the stress redistribution is revealed under thermo-hydro-mechanical coupling condition.
Time-dependent characteristics(TDCs)have been neglected in most previous studies investigating the deviation mechanisms of bridge pile foundations and evaluating the effectiveness of preventive *** this study,the stre...
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Time-dependent characteristics(TDCs)have been neglected in most previous studies investigating the deviation mechanisms of bridge pile foundations and evaluating the effectiveness of preventive *** this study,the stress-strain-time characteristics of soft soils were illustrated by consolidation-creep tests based on a typical engineering *** extended Koppejan model was developed and then embedded in a finite element(FE)model via a user-material subroutine(UMAT).Based on the validated FE model,the time-dependent deformation mechanism of the pile foundation was revealed,and the preventive effect of applying micropiles and stress-release holes to control the deviation was *** results show that the calculated maximum lateral displacement of the cap differs from the measured one by 6.5%,indicating that the derived extended Koppejan model reproduced the deviation process of the bridge cap-pile foundation with *** additional load acting on the pile side caused by soil lateral deformation was mainly concentrated within the soft soil layer and increased with the increase in load *** with t=3 d(where t is surcharge time),the maximum lateral additional pressure acting on Pile 2#increased by approximately 47.0%at t=224 *** bridge pile foundation deviation in deep soft soils,stress-release holes can provide better prevention compared to micropiles and are therefore recommended.
High beta-phase polyvinylidene fluoride (PVDF) thin films have excellent piezoelectricity and flexibility. They are widely used in wearable devices, hydroacoustic ultrasound, and energy harvesting. The preparation of ...
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High beta-phase polyvinylidene fluoride (PVDF) thin films have excellent piezoelectricity and flexibility. They are widely used in wearable devices, hydroacoustic ultrasound, and energy harvesting. The preparation of PVDF thin films by near-electric-field 3D printing can be customized in shape, and the high beta-phase can be obtained without stretching or polarization. In this work, the effects of polar solvent, printing voltage, and PVDF molecules on the beta-phase content of PVDF thin films prepared by near-electric-field 3D printing were analyzed. The results show that the polarity of the solvent affects the molecular chain conformation of PVDF, which is favorable for the generation of the beta-phase. With the increase of solvent polarity, the beta-phase content in PVDF films increased from 21.40% to 26.31%. The mutual motion of the collecting plate and the needle will produce stronger mechanical traction on the PVDF fibers, which is due to the smaller diameter of the PVDF fibers caused by the high printing voltage. The joint action of this tensile force and the strong electric field attraction promotes the beta-phase transition. When the printing voltage is 8 kV, the F(beta) value of PVDF film is increased by 47.37% over that without applied voltage. In addition, the interaction of small and large PVDF molecular weight will also result in mechanical deformation of the molecular chain and promote the beta-phase transition.
Purpose: This study evaluated pathogenic effect of TGF-beta 1/Smad3 pathway in mouse model after infecting them with HPI+ and HPI- strains of Escherichia coli (E. coli) which were isolated from diarrhea in calves. Met...
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Purpose: This study evaluated pathogenic effect of TGF-beta 1/Smad3 pathway in mouse model after infecting them with HPI+ and HPI- strains of Escherichia coli (E. coli) which were isolated from diarrhea in calves. Methods: Kunming mice were randomly divided into 3 groups: a control group, HPI+-infection group and HPI- infection group. After intraperitoneal injection of HPI strains of E. coli (concentration: 3 x 108 cfu/mL) in mice, alanine aminotransferase (ALT) and aspartate aminotransferase (AST), tumour necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) contents were detected at 12 h post infection. The sections of liver and kidney were obtained for histopathological observations. Propidium iodide and 4 ',6-diamidino-2-phenylindole (DAPI) staining was used to analyze the cell apoptosis. The immunohistochemistry staining and quantitative real time PCR (q-PCR) were performed for evaluating the protein and mRNA expression of TGF-beta 1, Collagen I and Smad3. The histological change and PI staining of liver and kidney showed significant injuries. Compared with the control group, the serum ALT and AST activities and TNF-alpha and IL-6 contents of mice in the HPI+ and HPI- groups were increased, number of apoptotic cells and expression of TGF-beta 1, Collagen Iand Smad3 were up-regulated after E. coli infection in liver and kidney, which was significantly increased in HPI+-infected compared to HPI-. Conclusion: The study concludes that E. coli HPI induced and enhanced the over expression of TGF-beta 1/Smad3 pathway and ultimately caused pathological anomalies.
Acrylonitrile-butadiene-styrene (ABS) resin is a widely used engineering plastic at present. Due to its excellent mechanical properties and high fluidity, it is utilized in fused deposition molding (FDM) technology. I...
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Acrylonitrile-butadiene-styrene (ABS) resin is a widely used engineering plastic at present. Due to its excellent mechanical properties and high fluidity, it is utilized in fused deposition molding (FDM) technology. In this paper, boron nitride nanosheets (BNNS) were prepared by hydrothermal exfoliation and used as nano-fillers for ABS resin, and ABS/BNNS composite wires for FDM printing were prepared by melt blending method. The results showed that BNNS with fewer layers were obtained;the addition of BNNS to the ABS resin matrix could effectively enhance the thermal conductivity of the composites. When the addition amount of BNNS was 15 wt%, the thermal conductivity of the composite increased to 0.369 W/(m K), which was 120.06 % higher than that of pure ABS (0.174 W/(m K)). In addition, BNNS also improves the mechanical properties, thermal stability, and melt flow rate of the composites, thus making ABS composite wires more suitable for FDM printing.
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