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Objective The polishing effects of different compositions of chairside polishing systems on polyetheretherketone (PEEK) were compared to provide a reference for the rational selection of polishing systems for this material in clinical settings. Methods A total of 108 specimens were made from ShushijieTMPEEK crown and bridge materials, Bio-PAEK® dental PEEK, and BioHPP® PEEK. Thirty-six specimens of each material were randomly divided into 6 groups on average based on their polishing technique: OptiDisc®, Super-Snap® Rainbow Technique Kit, VITA ENAMIC®Clinical Polishing Set, Sof-LexTM Diamond Polishing System, Visio.lign Finishing Kit for Composite Veneers, and CERAMAGE Polishing Kit, LavaTM Ultimate ceramic and VITA ENAMIC ceramics were set as the control groups, and 6 specimens were made in each material, polished by Sof-LexTM Diamond Polishing System and VITA ENAMIC® Polishing Set clinical, respectively, according to the manufacturers’ suggestions. The surface roughness (Ra value and Sa value) and gloss of each set were measured. The surface morphologies of the polished specimens were observed by scanning electron microscopy. Results Surface roughness (Ra value and Sa value) and gloss were mainly influenced by the type of polishing system, and they varied between PEEK material types. The Sof-LexTM Diamond Polishing System produced the highest surface roughness and the lowest gloss values for PEEK materials, while the Super-Snap® Rainbow Technique Kit, Visio.lign Finishing Kit for Composite Veneers and CERAMAGE Polishing Kit resulted in low surface roughness values. The Visio.lign Finishing Kit for Composite Veneers and CERAMAGE Polishing Kit exhibited high gloss values. Polishing paste particles were observed embedded on the surfaces of the PEEK materials polished by the Visio.lign Finishing Kit for Composite Veneers; the surfaces of specimens polished by the CERAMAGE Polishing Kit were smooth, without polishing paste particle residue. Using the same polishing system, the best polishing results were obtained with BioHPP® among the PEEK materials tested. The surface roughness values of the three tested PEEK materials polished by the CERAMAGE Polishing Kit were similar to those of the LavaTM Ultimate ceramic and VITA ENAMIC ceramic, but the gloss was higher than that of both. Conclusion CERAMAGE Polishing Kit was recommended for polishing all three tested PEEK materials, achieving a good polishing effect, with similar surface roughness and higher gloss characteristics comparable to those of polished computer-aided design and manufacturing (CAD/CAM) resin-matrix ceramics.

Ship detection in synthetic aperture radar (SAR) remote sensing images, being a fundamental but challenging problem in the field of satellite image analysis, plays an important role for a wide range of applications and is receiving significant attention in recent years. Aiming at the requirements of ship detection in high-resolution SAR images, the accuracy, the intelligent level, a better real-time operation and processing efficiency, The characteristics of ocean background and ship target in high-resolution SAR images were analyzed, we put forward a ship detection algorithm in high-resolution SAR images. The algorithm consists of two detection stages: The first step designs a pre-training classifier based on improved spectral residual visual model to obtain the visual salient regions containing ship targets quickly, then achieve the purpose of probably detection of ships. In the second stage, considering the Bayesian theory of binary hypothesis detection, a local maximum posterior probability (MAP) classifier is designed for the classification of pixels. After the parameter estimation and judgment criterion, the classification of pixels are carried out in the target areas to achieve the classification of two types of pixels in the salient regions. In the paper, several types of satellite image data, such as TerraSAR-X (TS-X), Radarsat-2, are used to evaluate the performance of detection methods. Comparing with classical CFAR detection algorithms, experimental results show that the algorithm can achieve a better effect of suppressing false alarms, which caused by the speckle noise and ocean clutter background inhomogeneity. At the same time, the detection speed is increased by 25% to 45%.

In order to solve the problems of difficult recognition of space-frequency block codes (SFBC) and high requirement of prior information in complex electromagnetic environment and non-cooperative communication, a blind recognition method of SFBC based on frequency cross-correlation sequence and peak detection is proposed. Firstly, by analyzing the coding characteristics of SFBC signals, the cross-correlation function of transmitter is calculated. Then, considering the influence of frequency selective channel, multipath propagation and noise, the cross-correlation function of the received signal is derived, and the frequency domain cross-correlation sequence is obtained by Fourier transform. Finally, based on the frequency domain cross- correlation sequence, the peak position is detected to identify the coding mode of the transmitter. The derivation and experimental results show that the algorithm has good recognition performance at low signal to noise ratio (SNR), strong adaptability to time deviation and frequency deviation, and has good recognition performance in complex electromagnetic environment. It can be applied to cognitive radio and spectrum detection. The algorithm does not need to know the priori information of channel and noise, the size of orthogonal frequency division multiplexing (OFDM) block and the synchronization information of receiver and transmitter, so it is very suitable for non-cooperative communication occasions such as electronic reconnaissance. [ABSTRACT FROM AUTHOR]

We present an approach for constructing a H2S-specific nanoprobe by the entrapment of a small molecule probe within the hydrophobic interior of surface cross-linked micelles (SCMs), endowing the designed nanoprobes with good water solubility and biocompatibility. Importantly, the obtained nanoprobes displayed good responsiveness to H2S in both ratiometric fluorescence and light-up NIR emission modes, thus enabling accurate identification of H2S-rich colorectal cancer cells. [ABSTRACT FROM AUTHOR]

We present an approach for constructing a H 2 S-specific nanoprobe by the entrapment of a small molecule probe within the hydrophobic interior of surface cross-linked micelles (SCMs), endowing the designed nanoprobes with good water solubility and biocompatibility. Importantly, the obtained nanoprobes displayed good responsiveness to H 2 S in both ratiometric fluorescence and light-up NIR emission modes, thus enabling accurate identification of H 2 S-rich colorectal cancer cells.

Xiong Ma Tang (XMT), one of the ancient herbal prescriptions, has been used in treatment of migraine disease. In this study, efficient high-performance liquid chromatographic fingerprints were developed for identification of 11 major marker components, named 1-(β-D-ribofuranosyl)-1H-1,2,4-triazone, gastrodin, ligustrazine, 3,4-bihydroxy benzaldehyde, p-hydroxy benzaldehyde, p-hydroxybenzoic acid, benzoic acid, vanillin, ferulic acid, caffeic acid and senkyunolide I, respectively, in XMT and three related preparations. The analysis of 11 marker compounds was carried out using a Kromasil C18 reserved-phase column (5 μm, 4.6 × 250 mm) and gradient elution with methanol and aqueous phosphoric acid (0.1%, v/v). The flow rate was 1.0 mL/min and the detector wavelength was set at 276 nm. Mean chromatograms and correlation coefficients of samples were calculated by the software "Similarity Evaluation System for Chromatographic Fingerprint of Traditional Chinese Medicine". The correlation coefficients of XMT and three related preparations ranged from 0.935 to 0.986, 0.909 to 0.949, 0.900 to 0.926 and 0.937 to 0.988, respectively. It was the first time 11 peaks of XMT and three related preparations were identified by comparing with standard compounds. These results have shown that the developed method was efficient for the quality evaluation of XMT and its related preparations., (© The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)