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  • Author: Wei-Xian Chen x
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Abstract

The aim of this study was to evaluate the diagnostic value of anti-mitochondrial antibodies (AMAs) and/or the M2 subtype (AMA-M2) in patients with primary biliary cirrhosis (PBC). AMA/AMA-M2 data were obtained by searching electronic databases. Studies showing AMA/AMA-M2 results in patients with PBC and control groups with other liver diseases or healthy livers were included. The quality of the involved studies was assessed using the QUADAS tool. The pooled sensitivity and specificity were calculated, and stratified analysis was performed according to possible heterogeneity sources. The pooled AMA (all methods) sensitivity and specificity were 84.5% (95% confidence interval (CI) 83.3%–85.6%) and 97.8% (95% CI 97.6%–98.0%), respectively. The positive and negative likelihood ratios were 25.201 (95% CI 17.583–36.118) and 0.162 (95% CI 0.131–0.199), respectively. The current evidence suggests that AMA and AMA-M2 show favorable accuracy for the diagnosis of PBC with high specificity and sensitivity. AMA is a better and more comprehensive marker than AMA-M2. The accuracy established in this meta-analysis is based on clinical studies using patient cohorts from different ethnicities.

Abstract

The aim of this work was to assess the diagnostic value of anti-CCP-3 and anti-CCP-2 for the diagnosis of rheumatoid arthritis (RA) and determine whether anti-CCP-3 more accurately identifies patients with rheumatoid arthritis than anti-CCP-2. PubMed and CNKI databases were searched for studies published in English and Chinese that examined the use of anti-CCP-3 and anti-CCP-2 in the diagnosis of known or suspected rheumatoid arthritis from January 2006 to July 2013. Seventeen included studies of methodological quality were rated by using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS) tools A random-effects method was used to summarize sensitivities, specificities, positive and negative likelihood ratio (LR+ and LR−, respectively), and diagnostic odds ratio from 17 studies. The pooled sensitivity, specificity, LR+, LR− and diagnostic odds ratio for anti-CCP-3 were 0.737 (95% CI, 0.717–0.757), 0.933 (95% CI, 0.924–0.942), 11.096 (95% CI, 8.876–13.870), 0.274 (95% CI, 0.231–0.326), and 42.908 (95% CI, 33.828–54.426), respectively. For anti-CCP-2, the values were 0.719 (95% CI, 0.699–0.739), 0.960 (95% CI, 0.953–0.966), 17.485 (95% CI, 11.960–25.562), 0.294 (95% CI, 0.258–0.335) and 63.458 (95% CI, 44.214–91.078), respectively. With high specificity and moderate sensitivity, anti-CCP-2 and anti-CCP-3 played an important role in confirming the diagnosis of RA. Anti-CCP-3 did not have better diagnostic performances than anti-CCP-2, but anti-CCP-2 had evident heterogeneity compared to anti-CCP-3, especially in American patients.

Abstract

The minimum of oxygen content in the deoxidation equilibrium in liquid iron was thermodynamically analyzed in the present paper. Two criteria were developed to determine the existence of the minimum. The first criterion was 0xγMM+yγOMmin(x/4.606[%M]ex2,(xeMM+yeOM)2/3.474x) with xeMM+yeOM<0, or xγMM+yγOM<0. And the second criterion was (xeMO+yeOO)+y/2.303[%O]ex>0. The criteria in terms of first-order activity interaction parameters were the special case of present thermodynamic analysis with neglecting the second-order activity interaction parameters. They were not fit for the case of xeMM+yeOM>0, in which case the criteria in terms of second-order activity interaction parameters should be taken into account to determine the existence of the minimum. The value 0.11 of eSiSi was smaller based on the existence of the minimum for the Fe-O-Si system. It was guaranteed that the minimum value of oxygen content on the deoxidation equilibrium curve existed at silicon content 20 mass%, when the value 0.32 of eSiSi was chosen, and the second-order activity interaction coefficients γSiSi and γOSi satisfied the condition γSiSi+2γOSi=1.54×103.

The electron paramagnetic resonance (EPR) anisotropic g-factors gx, gy and gz and hyperfine structure constants Ax, Ay and Az of Cu2+ in Cs2ZnCl4 crystal are theoretically investigated by the method of diagonalizing the full Hamiltonian matrix. The crystal-field parameters are obtained from the crystal structure by the superposition model. The results, agreeing reasonably with the observed values, are discussed.

Abstract

Fluorinated carbon (CFx), a thriving member of the carbonaceous derivative, possesses various excellent properties of chemically stable, tunable bandgap, good thermal conductivity and stability, and super-hydrophobic due to its unique structures and polar C-F bonding. Herein, we present a brief review of the recent development of fluorinated carbon materials in terms of structures, properties and preparation techniques. Meanwhile, the applications in energy conversions and storage devices, biomedicines, gas sensors, electronic devices, and microwave absorption devices are also presented. The fluorinated carbon contains various types of C-F bonds including ionic, semi-ionic and covalent C-F, C-F2, C-F3 bonds with tunable F/C ratios. The controllable designing of C-F bonding and F/C ratios play a key role to optimize the properties of fluorinated carbon materials. Until now, the potential issues and future opportunities of fluorinated carbon are proposed. The present review will provide a direction for tuning C-F bonding and F/C ratios, developing a safe and efficient fluorination method and popularizing the applications of fluorinated carbon materials.

Abstract

Graphite felt (GF) with numerous merits has been widely used as electrode in all-vanadium redox flow batteries (VRFB), but its further application is still hindered by its intrinsically poor electrocatalytic activity. Herein, we propose a three-dimensional (3D) conducting network constructed with reduced graphene oxide (rGO) in the GF electrode via a two-step method. The 3D conducting network with abundant oxygen-containing functional groups in the GF is conducive to the transport of electrons between GF fibers and the electrochemical charge transfer to vanadium ions in the composite electrode; it can enhance the electrocatalytic activity and conductivity of GF. The VRFB using 3D rGO modified GF (mGF) electrode exhibited outstanding energy efficiency of 73.4% at a current density of 100 mA·cm−2, which is much higher than that with pristine GF (pGF) (65.4%); and better rate capability. These first results reveal that GF with 3D conducting network shows promising opportunities for the VRFB and other electrochemical flow systems

Abstract

The localized states in ZnO nanowires (NWs) through the growth of ZnS shell have been introduced in this paper. Morphology and optical properties of the ZnO/ZnS core-shell heterostructured NWs after different rapid thermal annealing (RTA) treatments are investigated. Transmission electron microscopy measurements show the gradual disappearing of the jagged boundary between ZnO and ZnS with the increase of RTA temperature, while a decrease of interfacial composition fluctuation and a formation of ZnOS phase can be found after a RTA treatment of 300°C. Temperature-dependent photoluminescence exhibits the features of “S-shape” peak positions and a “valley shape” for the emission width, implying the existence of localized excitons in the core-shell NWs. Moreover, it is noted that the RTA treatments can lower the localized degree which is confirmed by optical measurement. The results indicate that the optical behavior of excitons in ZnO/ZnS core-shell heterostructured NWs can be manipulated by appropriate thermal treatments, which is very important for their practical device applications.