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Manganese monoxide (MnO) is a promising anode material for lithium ion batteries, but it often shows poor electrochemical performance due to some inevitable drawbacks including intrinsic low electrical conductivity, poor stability, and severe polarization. In this work, a 1D core‐shell MnO@S, N co‐doped carbon material (MnO@SNC) was obtained by pyrolysis of MnO2@PPy precursor at 600 °C in N2 atmosphere. When evaluated as an anode for lithium ion batteries, the unique structure and composition advantages endow the as‐formed material with excellent lithium storage performance in terms of high specific capacity (955.5 mAh g−1 at a current density of 500 mA g−1), long‐term cycling stability (up to 500 cycles), and superior rate capability (458.7 mAh g−1 at a current density of 2 A g−1). The outstanding electrochemical performance could be attributed to the unique 1D core‐shell structure, abundant graphited carbon and MnO nanorods. [ABSTRACT FROM AUTHOR]

Summary: In this paper, a new practical robust control scheme is proposed and investigated for the cable‐driven manipulators under lumped uncertainties. There are three parts in the proposed method, ie, a time‐delay estimation (TDE) part, a modified super‐twisting algorithm (STA) part, and a fractional‐order nonsingular terminal sliding mode (FONTSM) error dynamics part. The TDE uses intentionally time‐delayed system signals to estimate the lumped dynamics of the system and ensures an attractive model‐free control structure. The STA is applied to guarantee high performance and chattering suppression simultaneously in the reaching phase. The FONTSM error dynamics is utilized to obtain fast convergence and strong robustness in the sliding mode phase. Thanks to the above three parts, the proposed control scheme is model free and can ensure high control performance under lumped uncertainties. The stability considering the FONTSM error dynamics and modified STA scheme is analyzed. Comparative simulation and experiments were conducted to demonstrate the effectiveness and superiorities of the newly proposed control scheme. Corresponding experimental results show that our newly proposed control scheme can provide more than 20% improvement of the steady control accuracy under three different reference trajectories. [ABSTRACT FROM AUTHOR]

Objectives: The aim of our study was to evaluate the clinical application of color Doppler flow imaging (CDFI) and acoustic radiation force impulse (ARFI) for the diagnosis of acute rejection after liver transplantation. Methods: B‐Mode CDFI and ARFI assessments were performed in 76 patients who underwent biopsy after liver transplantation at our institution, between October 2011 and October 2014. The study group included 56 patients with acute rejection confirmed by biopsy, with 20 patients whose liver function recovered within 1 month of transplantation forming the control group. Anteroposterior diameter of the liver, hemodynamic index (consisting of the portal vein diameter, portal vein flow velocity, and hepatic vein flow waveform), and ARFI shear wave velocity (SWV) were measured. We used logistic regression modeling and receiver operating curve to evaluate between‐group differences. Results: Compared with the control group, patients with acute rejection exhibited increased anteroposterior diameter (P = .035) and change in hemodynamic index (P = .021), including increased portal vein diameter, decreased portal vein flow, and loss of triphasic waveform of hepatic vein flow. Acoustic radiation force impulse SWV was markedly increased in the acute rejection group (P < .001). The correlation r‐value of measured parameters to acute rejection diagnosis was 0.253 for anterioposterior diameters, 0.271 for change in hemodynamic index, and 0.721 for increased SWV. Shear wave velocity and change in the hemodynamic index had diagnostic value, with an area under the receiver operating curve of 0.933. Conclusions: Combining CDFI with ARFI was useful for the diagnosis of acute rejection after liver transplantation. [ABSTRACT FROM AUTHOR]

Chitosan/Ag-montmorillonite (CS/Ag-MMT) nanocomposite was obtained via solution intercalation. The X-ray diffraction and transmission electron microscopy results indicated the successful formation of intercalated-and-exfoliated nanostructures at low Ag-MMT contents and intercalated-and-flocculated nanostructures at high Ag-MMT contents. The CS/Ag-MMT nanocomposite with 7 wt% Ag-MMT presented a very high inhibition ratio against Staphylococcus aureus (>70%), and its bacterial inhibition zone diameter was 3.2 mm larger than that of CS, which showed remarkable antibacterial activity. When the Ag-MMT content was 5 wt%, the E′ of CS/Ag-MMT was increased to 3,261 MPa, which was 195% higher than CS and exhibited excellent mechanic property. The DMA test results showed the Tg of CS/Ag-MMT shifted to a higher temperature, suggesting the Ag-MMT interlayer not only interacted quite strongly with the reactive groups of CS but also restricted the motion of CS macromolecules, which was also verified by Fourier transform infrared spectrum measurements. POLYM. COMPOS., 35:1980-1988, 2014. © 2014 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]