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Dynamic soft tissue characterisation is an important element in robotic minimally invasive surgery. This paper presents a novel method by combining neural network with recursive least square (RLS) estimation for dynamic soft tissue characterisation based on the nonlinear Hunt-Crossley (HC) model. It develops a radial basis function neural network (RBFNN) to compensate for the error caused by natural logarithmic factorisation (NLF) of the HC model for dynamic RLS estimation of soft tissue properties. The RBFNN weights are estimated according to the maximum likelihood principle to evaluate the probability distribution of the neural network modelling residual. Further, by using the linearisation error modelled by RBFNN to compensate for the linearised HC model, an RBFNN-based RLS algorithm is developed for dynamic soft tissue characterisation. Simulation and experimental results demonstrate that the proposed method can effectively model the natural logarithmic linearisation error, leading to improved accuracy for RLS estimation of the HC model parameters. [ABSTRACT FROM AUTHOR]

Abstract Ethnopharmacological relevance The abnormal increase in vascular smooth muscle cell (VSMC) proliferation and migration are critical events in the pathogenesis of cardiovascular diseases (CVDs) including restenosis and atherosclerosis. The dried roots of Scutellaria baicalensis Georgi (common name: Huangqin in China) have been confirmed to possess beneficial effects on CVD by clinical and modern pharmacological studies. Flavonoids in Huangqin exert anti-proliferative and anti-migratory effects. Similar to Huangqin, Scutellaria strigillosa Hemsley (SSH) has been used to clear heat and damp and is especially rich in flavonoids including wogonin, wogonoside, baicalein, and baicalin. However, there have been few of reports about pharmacological activities of SSH. Aim of the study To investigate the anti-proliferative and anti-migratory properties of Scutellaria strigillosa Hemsley extract (SSHE) in vitro and in vivo and explore its possible mechanism of action. Materials and methods The chemical constituents of SSHE were analyzed by ultra-high performance liquid chromatography coupled with triple time-of-flight mass spectrometry (UPLC-Triple-TOF-MS/MS). Cell proliferation and migration were investigated using BrdU incorporation assay and cell scratch test, respectively. The protein expression was determined by western blotting. In vivo , we established an artery ligation model of C57BL/6 mice and orally administered them with 50 or 100 mg/kg/day of SSHE. The carotid arteries were harvested and the intima-media thickness was examined 28 days post-ligation. Results Twelve compounds were identified and tentatively characterized. SSHE significantly inhibited the VSMC proliferation and migration stimulated by PDGF-BB and decreased the relative protein expression of regulatory signaling intermediates. Furthermore, the expression of SM22α was significantly elevated in SSHE-pretreated VSMCs, whereas knockdown of SM22α impaired the PDGF-BB-induced proliferation and migration arrest. Meanwhile, both ROS generation and the phosphorylation of ERK decreased in SSHE-pretreated VSMCs. In carotid artery ligation mice model, SSHE treatment significantly inhibited neointimal hyperplasia. Conclusions SSHE significantly inhibited the PDGF-BB-induced VSMC proliferation, migration, and neointimal hyperplasia of carotid artery caused by ligation. Upregulation of SM22α expression, inhibition of ROS generation and ERK phosphorylation were, at least, partly responsible for the effects of SSHE on VSMCs. Graphical abstract fx1 [ABSTRACT FROM AUTHOR]

The effects of anion-tuning on cobalt-based chalcogenides for OER in weakly alkaline seawater are comprehensively investigated via DFT, XAS, and XPS, and S substitution is proven to optimize the electronic structure of active site to prevent Cl* from transforming to ClO- for anti-corrosion. Co 3 S 4 could stably operate at the high current density of 100 mA cm−2 for 100h without any performance degradation. [Display omitted] • Co 3 S 4 and Co 3 Se 4 were transformed from the Co 3 O 4 precursor by hydrothermal method. • DFT predicts the possible active sites and mechanisms of OER and HCER in seawater. • S and Se substitution increases energy barrier of Cl* to ClO- for anti-corrosion. • S and Se could promote Co site transforming to active phase. • Co 3 S 4 stably operates at OER current density of 100 mA cm−2 in weakly alkaline seawater for 100 h and netrual seawater for 20 h. Regulating the electronic structure is of great importance for improving the performance, stability, and selectivity of seawater splitting catalysts. Herein, cobalt-based oxide and chalcogenide (Co 3 X 4 , X = O, S, and Se) are synthesized to investigate the effect of anions on the electronic structure, catalytic performance and selectivity of the seawater oxidation catalysts. The theoretical calculations predict the possible active sites of oxygen evolution reaction and hypochlorite evolution reaction. Then the experimental characterization and calculation results demonstrate that S and Se substitution could regulate the electronic structure and d-band center of Co site, enhance the metallicity of catalysts. Moreover, the energy barrier of Cl* conversion to ClO- could be modulated for preventing the formation of ClO- by anions regulating. Consequently, Co 3 S 4 could stably operate at a current density of 100 mA cm−2 in 0.1 M KOH + 0.6 M NaCl for 100 h and in neutral seawater for 20 h. [ABSTRACT FROM AUTHOR]

The nonlinear flutter of a narrow railway truss girder are studied through free vibration and forced vibration wind tunnel tests. Four functions are used to fit the structural amplitude-varying damping ratio under no wind condition, and the fourth-order polynomial has higher goodness-of-fit. The narrow truss girder shows nonlinear flutter of a velocity-restricted type without amplitude hysteresis. At large angles of attack (AoA), the vertical participation and the AoA have little effect on the onset wind speed and amplitude. While at medium AoAs, even a low vertical participation level will increase the onset wind speed and decrease the amplitude. At small AoAs, there is no vibration observed. The flutter derivative A 2 * is positive only in the limited reduced wind speed and amplitude range. The nonlinearity of self-excited lifting moment is higher only in the limited reduced wind speed and amplitude range, while that of self-excited lift is weaker and becomes stronger with the increasing amplitude and reduced wind speed. The negative aerodynamic damping is mainly provided by the flutter derivative A 2 * at small or large AoAs. Generally, the nonlinear flutter response is mainly controlled by the first-order component of the self-excited force, and the influence of high-order components can be ignored. • Relatively complete study of a narrow truss girder's nonlinear flutter characteristics. • The unique characteristics of the key flutter derivative A 2 * and self-excited lifting moment. • Analysis and verification of the influence of higher-order components of self-excited force on nonlinear flutter. [ABSTRACT FROM AUTHOR]

Compounds with Cs 3 CoCl 5 structure usually exhibit a large Debay temperature with a large band gap, which has been considered as new host materials for WLED application. Oxide materials of the Cs 3 CoCl 5 structure have great luminescence characteristics, thus it is more worthwhile to research Cl-based materials with higher electronegativity. Here, an Mn2+ activated Cs 3 ZnCl 5 narrow band green emitting phosphor was developed and investigated in detail. Ternary alkaline chloride Cs 3 ZnCl 5 was successfully prepared by a coprecipitation method. XRD refinement, SEM and XPS have proved the successful preparation of Cs 3 ZnCl 5 : 6%Mn2+ with a single phase. The electronic structure investigation clearly states that Cs 3 ZnCl 5 has a large band gap with Eg∼4.467 eV. The Cs 3 ZnCl 5 : 6%Mn2+ phosphor can also generate green light with a peak wavelength of 525 nm and a fullwidth at half-maximum (FWHM) of 47 nm when excited by blue light at 451 nm. The luminescent property, as well as the concentration-dependent emission decay behavior of Cs 3 ZnCl 5 : 6%Mn2+ at room temperature, were studied. Over the temperature range of 30–120 °C, the thermal quenching performance of Cs 3 ZnCl 5 : 6%Mn2+ was investigated, and the related mechanism was discussed through thermoluminescence analysis. Electron traps transmit energy to the Mn2+ luminescence center after 120 °C, which will increase the emission intensity. Finally, a blue light-pumped white LED was constructed using this phosphor in combination with commercially available red phosphors. The findings above suggested that Cs 3 ZnCl 5 : 6%Mn2+ could be served as a potential green-emitting phosphor for white light-emitting diodes. • The Cs 3 ZnCl 5 : Mn2+ phosphors are successful prepared. • The abnormal thermal quenching have been discussed in detail. • The Cs 3 ZnCl 5 : Mn2+ phosphors have a green emitting at 525 nm. • The Cs 3 ZnCl 5 : Mn2+ phosphors can be used in WLEDs. [ABSTRACT FROM AUTHOR]

Accurately identifying the aerodynamic loads on vehicles is the fundamental issue for assessing the driving safety of vehicles on long-span bridges subjected to strong crosswinds. Thus, the aerodynamic interference of bridges with vehicles must be considered. However, very few studies have been conducted to quantify both the steady and unsteady crosswind loads for vehicles on wide bridge decks. In this paper, the mean and peak aerodynamic coefficients and aerodynamic admittance functions for three types of high-sided vehicles (medium trucks, buses, and tractor-trailers) on two wide bridge decks (a single-box girder and a twin-box girder) were determined by means of wind tunnel tests. The effects of vehicle position, wind angle of attack, and geometric shape of the deck on these aerodynamic parameters were investigated. The results show that the aerodynamic coefficients of vehicles on both bridge decks vary significantly with their lateral position. Moreover, the effect of wind angle of attack on the aerodynamic coefficients of vehicles on the leeward side of the twin-box girder is extremely substantial, as is the geometric shape of the bridge deck. However, the vehicle position, wind angle of attack, and bridge deck geometry all have little influence on the aerodynamic admittance functions of vehicles. • Various cases on steady and unsteady aerodynamic forces of vehicles on two wide bridge decks under crosswind are studied. • Bridge deck geometry, vehicle position and wind angle of attack have significant effects on aerodynamic parameters of vehicles on bridge decks. • Empirical expressions of aerodynamic admittance functions of vehicles on wide bridge decks are fitted. [ABSTRACT FROM AUTHOR]

Background Hepatocellular carcinoma (HCC) is the most common type of liver cancer with high mortality and poor prognosis. Mitogen-activated protein kinase (MAPK) and nuclear factor kappa B (NF-κB) signaling pathways have been implicated in promoting tumor cell proliferation and invasion of HCC cells. Methods As a potential inhibitor of tumor metastasis, the role of Raf kinase inhibitor protein (RKIP) in HCC development and the functional relevance with MAPK and NF-κB signaling pathways were investigated. The levels of RKIP expression were examined in human HCC tissues and correlated with tumor stages and metastatic status. Function of RKIP in cellular proliferation, migration, invasion and apoptosis was investigated in HCC cell lines by either overexpressing or knocking down RKIP expression. Mouse xenograft model was established to assess the effect of RKIP expression on tumor growth. Results Our results demonstrated decreased RKIP expression in HCC tissues and a strong correlation with tumor grade and distant metastasis. Manipulation of RKIP expression in HCCLM3 and HepG2 cells indicated that RKIP functioned to inhibit HCC cell motility and invasiveness, and contributed to tumor growth inhibition in vivo . Mechanistic studies showed that the function of RKIP was mediated through MAPK and NF-κB signaling pathways. However, cell type-dependent RKIP regulation on these two pathways was also suggested, indicating the complex nature of signaling network. Conclusion Our study provides a better understanding on the molecular mechanisms of HCC metastasis and sets the foundation for the development of targeted therapeutics for HCC. [ABSTRACT FROM AUTHOR]