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In this paper, alumina-reinforced copper-based composite materials were prepared by using the electroless plating method to coat copper powder with a layer of silver and then combining the solution sol method and powder metallurgy method. The results show that recrystallized structures and twins appear in composite materials after high-temperature sintering. As the sintering temperature increases, the ratio of recrystallized structures and twins gradually decreases, and straight coherent Σ3 annealing twins appear in the structure, the number of high-angle grain boundaries decreased, the number of small-angle grain boundaries continues to increase, the average grain size increased from 3.89 to 4.83μm, the tensile strength increased from 156MPa to 167.5MPa, the maximum elongation was 9.4%, and the density increased from 6.81g/cm3 increased to 7.62g/cm3, the porosity dropped from 13.3% to 5.5%, the conductivity increased from 60.3% IACS to 73.2% IACS, the maximum hardness value was 68.71 HV, the best performance of the composite was achieved by sintering at 900°C with the tensile strength and elongation are 163MPa and 9%, respectively, the conductivity is 68.9% IACS, and the density is 7.35g/cm3. Its fracture surface shows mostly ductile features. [ABSTRACT FROM AUTHOR]

Modulation of electronic structure via heterointerface engineering is regarded as an appealing strategy to promote the hydrogen evolution reaction (HER) performance of a pH-universal electrocatalyst. Herein, the CoS 2 -MoS 2 heterostructure is synthesized, where MoS 2 nanosheets are vertically anchored on CoS 2 microflakes. Plentiful heterogeneous nanointerfaces generated between MoS 2 and CoS 2 phases not only provide sufficient electroactive sites and structural defects, but also afford a hierarchically porous structure. The synergistic modulation of electronic and geometric structures accounts for a superb catalytic activity and long-durability of CoS 2 -MoS 2 toward HER in acidic and alkaline solutions simultaneously, in terms of the overpotential in 0.5 M H 2 SO 4 (218 mV versus RHE) and 1.0 M KOH (251 mV) at a current density of 10 mA cm−2. This work offers an exciting avenue for fabricating transition metal sulfides as efficient wide-pH electrocatalysts through an interface-induced strategy. [Display omitted] • Fabrication of CoS 2 -MoS 2 heterostructure via an interface-induced approach. • The first 2D–2D heterostructure of CoS 2 -MoS 2 towards efficient HER in wide-pH media. • Synergistic modulation of electronic and geometric structures for a superb dual-pH HER. [ABSTRACT FROM AUTHOR]

Titanium matrix composites were prepared by investment casting in a consumable arc skull casting furnace. With the addition of BC, the average primary β grains are refined, and the morphology of α phase tends to be more equiaxed. The free energy for nucleation consisting of the bulk free energy, orientation-independent interfacial energy, and elastic strain energy is calculated to investigate the role of nucleation sites in determining the shape of critical nucleus. In the current study, the TiB whiskers were found to be arranged in the grain boundary and provide heterogeneous nucleation sites for α precipitates, and the interfacial energy is about 14 % more than that in Ti-64, while its elastic strain energy is reduced to about three quarters of the latter one. [ABSTRACT FROM AUTHOR]

We propose an improved coarse-grain scalable video coding (SVC) approach based on the structural similarity (SSIM) index as the visual quality criterion, aiming at maximizing the overall coding performance constrained by user-defined quality weightings for all scalable layers. First, we develop an interlayer rate-SSIM dependency model, by investigating bit rate and SSIM relationships between different layers. Second, a reduced-reference SSIM-Q model and a Laplacian R-Q model are introduced for SVC, by incorporating the characteristics of hierarchical prediction structure in each layer. Third, based on the user-defined weightings and the proposed models, we design a rate-distortion optimization approach to adaptively adjust Lagrange multipliers for all layers to maximize the overall rate-SSIM performance of the scalable encoder. Experiments with multiple layers, different layer weightings, and various videos demonstrate that the proposed framework can achieve better rate-SSIM performance than single layer optimization method, and provide better coding efficiency as compared to the conventional SVC scheme. Subjective tests further demonstrate the benefits of the proposed scheme. [ABSTRACT FROM AUTHOR]

Titanium matrix composites (TMCs) are prepared by investment casting in a vacuum consumable kish furnace. The effects of B 4 C additions on the microstructures and tensile properties of TMCs are investigated. With the addition of B 4 C, the microstructure of TMCs is refined and the strength is improved. The yield strength of TMCs is evaluated by a comprehensive model that combines the strengthening effects of TiB whiskers/TiC particles, grain refinement and solution strengthening of the matrix, which is consistent with the experimental results in the current study. It is found that the yield strength enhancement of TMCs is mainly due to grain refinement and solution strengthening. During tensile deformation, the dislocation piles up at the interface between TiB whisker and matrix, which allows the TiB whiskers to bear extra load and therefore enhances the strength of TMCs. The plastic deformation is localized due to the action of TiB whiskers and this results in the brittle fracture of TMCs. [ABSTRACT FROM AUTHOR]

Colorectal cancer is one of the most prevalent malignancies in the world. Chinese researchers and clinical doctors had been working hard in the last 12 years, exploring efficient and convenient methods for screening and early diagnosis. The 12 years research works indicated that SFOBT plus colonoscopy was the best detecting protocol for mass screening of colorectal cancer. Serial combined testing for tumor markers plus colonoscopy is the most commonly used strategy for early diagnosis. However, still no optimum method for early diagnosis was generally accepted by most researchers. Due to intrinsic defects of the techniques, several screening and diagnostic methods should be combined to bring each advantage into full play, in order to elevate the diagnostic level of colorectal cancer. [ABSTRACT FROM AUTHOR]

In this work, (TiB + TiC)/Ti6Al4V composites (TMCs) were prepared by in situ synthesis technology, and were successfully hot indirect extruded at four extrusion temperatures containing below and above β phase transition temperature (T = 1214K, 1259K, 1304K and 1349K). The effect of extrusion temperatures on the matrix, reinforcements and strengthening mechanisms were systematically studied. The results show that the mechanical effects has significantly influence on the microstructures of TMCs below β transformation temperatures, and more elongated α grains are formed. At the temperature of 1214K the α grain refinement mechanisms are controlled by dislocation motion, and there are a large number of dislocations within or between grains, which make the main contribution to the highest yield strength of the TMCs. With the increase of extrusion temperature, the yield strength decreases gradually, while the elongation increases gradually at first and then decreases slightly. This is because the grain refinement mechanism is mainly dynamic recrystallization, and coarser and dislocation-free α grains are formed at the temperature of 1349K. The indirect extrusion temperature should be controlled below the β transus. However, lower or near β transus can result in more fractures of TiB whiskers, which has a negative effect on the mechanical properties of TMCs. [ABSTRACT FROM AUTHOR]

Objective To investigate the cause and treatment of delayed hemobilia after endoscopic retrograde cholangiopancreatography (Methods). ERCP A retrospective analysis was performed on the complications in 1007 patients after ERCP, and the 7 cases of delayed hemobilia were subjected to analysis of time of onset of bleeding, spectrum of disease, blood volume, and treatment process. Results All the bleeding patients had cholangitis. The bleeding occurred at 24 hours to 2 weeks after ERCP, with a small to medium volume of blood (≥ 1000 ml). The conservative medical treatment produced a good outcome in these bleeding patients. Conclusion Delayed hemobilia after ERCP is rare and has a good prognosis following conservative medical treatment. [ABSTRACT FROM AUTHOR]

In this paper, we propose a two-stage weighting based perceptual quality assessment framework for asymmetrically distorted stereoscopic video (SV) sequences by temporal binocular rivalry. Firstly, a traditional 2D image quality assessment (IQA) method is employed to measure spatial distortion, and the temporal distortion is evaluated by the magnitude differences between motion vectors of distorted and reference video frames. Secondly, the structural strength (SS) computed by gradient map and the motion energy (ME) computed by frame difference map are used to estimate the intensity of visual stimulus in spatial and temporal domain respectively. Then, SS and ME are considered as the importance indexes to combine the quality scores of spatial and temporal distortion to estimate perceived distortion of single-view video sequences, which is denoted as the first-stage weighting. Finally, considering that the difference of intensity of visual stimulus between two eyes results in binocular rivalry, a novel temporal binocular rivalry inspired weighting method is designed to integrate the quality scores of left- and right-views for the final visual quality prediction of SV sequences, which is denoted as the second-stage weighting. Experimental results on Waterloo-IVC SV quality databases show that several specific examples of 2D-IQA methods within the proposed framework can obtain highly competitive performance over other existing ones. [ABSTRACT FROM AUTHOR]

Few studies have provided data on the metabolomics characteristics of metabolic diseases such as hyperuricemia and hyperbilirubinemia in the Tibetan plateau. In the current study, we sought to investigate the serum metabolomics characteristics of hyperbilirubinemia and hyperuricemia in the Tibetan plateau, with the aim to provide a basis for further research on their pathogenesis, prevention, and treatment. The study participants were born in low-altitude areas below 1000 m and had no prior experience living in a high-altitude area before entering Golmud, Tibet (average elevation: 3000 m) and Yushu, Qinghai (average elevation: 4200 m). Thirty-four participants with hyperbilirubinemia (18 in Golmud and 16 in Yushu), 24 participants with hyperuricemia, and 22 healthy controls were enrolled. The serum samples of subjects were separated and then sent to a local tertiary hospital for biochemical examination. Serum widely targeted technology, based on the ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) platform, was used to detect serum metabolites and differential metabolites. Compared to the healthy controls, hyperbilirubinemia patients from Golmud showed 19 differential metabolites, hyperbilirubinemia patients from Yushu showed 12 differential metabolites, and hyperuricemia patients from Yushu showed 23 differential metabolites. Compared to the hyperbilirubinemia patients from Golmud that is at a low altitude, the Yushu groups had 33 different metabolites. Differential metabolites are primarily classified into amino acids and their derivatives, nucleotides and their derivatives, organic acids and their derivatives, and lipids/fatty acids. These are related to metabolic pathways such as caffeine metabolism, arachidonic acid metabolism, and tyrosine metabolism. Hyperbilirubinemia and hyperuricemia in the Tibetan plateau have unique serum metabolomics characteristics. Glycine derivatives and arachidonic acid and its derivatives were associated with plateau hyperbilirubinemia, and vanillic acid and pentadecafluorooctanoic acid were associated with plateau hyperuricemia. [ABSTRACT FROM AUTHOR]

Few studies have provided data on the metabolomics characteristics of metabolic diseases such as hyperuricemia and hyperbilirubinemia in the Tibetan plateau. In the current study, we sought to investigate the serum metabolomics characteristics of hyperbilirubinemia and hyperuricemia in the Tibetan plateau, with the aim to provide a basis for further research on their pathogenesis, prevention, and treatment. The study participants were born in low-altitude areas below 1000 m and had no prior experience living in a high-altitude area before entering Golmud, Tibet (average elevation: 3000 m) and Yushu, Qinghai (average elevation: 4200 m). Thirty-four participants with hyperbilirubinemia (18 in Golmud and 16 in Yushu), 24 participants with hyperuricemia, and 22 healthy controls were enrolled. The serum samples of subjects were separated and then sent to a local tertiary hospital for biochemical examination. Serum widely targeted technology, based on the ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) platform, was used to detect serum metabolites and differential metabolites. Compared to the healthy controls, hyperbilirubinemia patients from Golmud showed 19 differential metabolites, hyperbilirubinemia patients from Yushu showed 12 differential metabolites, and hyperuricemia patients from Yushu showed 23 differential metabolites. Compared to the hyperbilirubinemia patients from Golmud that is at a low altitude, the Yushu groups had 33 different metabolites. Differential metabolites are primarily classified into amino acids and their derivatives, nucleotides and their derivatives, organic acids and their derivatives, and lipids/fatty acids. These are related to metabolic pathways such as caffeine metabolism, arachidonic acid metabolism, and tyrosine metabolism. Hyperbilirubinemia and hyperuricemia in the Tibetan plateau have unique serum metabolomics characteristics. Glycine derivatives and arachidonic acid and its derivatives were associated with plateau hyperbilirubinemia, and vanillic acid and pentadecafluorooctanoic acid were associated with plateau hyperuricemia. [ABSTRACT FROM AUTHOR]

Abstract: Complex wavelet structural similarity (CW-SSIM) index has been recognized as a novel image similarity measure of broad potential applications due to its robustness to small geometric distortions such as translation, scaling and rotation of images. Nevertheless, how to make the best use of it in image classification problems has not been deeply investigated. In this paper, we introduce a series of novel image classification algorithms based on CW-SSIM and use handwritten digit recognition, and face recognition as examples for demonstration. Among the proposed approaches, the best compromise between accuracy and complexity is obtained by the CW-SSIM support vector machine based algorithms, which combines an unsupervised clustering method to divide the training images into clusters with representative images and a supervised learning method based on support vector machines to maximize the classification accuracy. Our experiments show that such a conceptually simple image classification method, which does not involve any registration, intensity normalization or sophisticated feature extraction processes, and does not rely on any modeling of the image patterns or distortion processes, achieves competitive performance with reduced computational cost. [Copyright &y& Elsevier]

Background: Fibromuscular dysplasia (FMD) is a type of unexplained nonatherosclerotic vascular disease that usually involves the renal and internal carotid arteries and rarely involves the mesenteric artery. Mesenteric artery FMD is difficult to distinguish from Crohn's disease (CD) and Behcet's disease (BD) solely based on symptoms. Patients with mesenteric artery FMD can present with an acute abdomen, but case reports of patients who have a long medical history and undergo multiple bowel resections are extremely rare.Case Presentation: The patient was a 45-year-old woman with an 11-year history of intermittent lower abdominal pain and fever. At the age of 34 years, she underwent right hemicolectomy and appendectomy due to an acute abdomen. She suffered from oral ulcers between 34 and 36 years old. A clinical diagnosis of presumed CD was made by the age of 41, and she was treated with mesalazine; however, the effect was poor. At the age of 42, she came to our centre, and based on her atypical symptoms and examination results, we thought she had CD. Hence, she was treated with glucocorticoids for 3 years. However, when she was 45, due to steroid dependence, thalidomide tablets were added. Unfortunately, she suffered from another episode of intestinal obstruction. Therefore, she underwent enterectomy. The postoperative histopathological diagnosis was mesenteric artery FMD. She no longer underwent pharmacotherapy after the surgery. Although she did not have any of her previous symptoms and postoperative colonoscopy showed no signs of recurrence, splenomegaly and abnormal routine blood results were still present.Conclusions: Patients with mesenteric artery FMD can present with an acute abdomen. In addition, the symptoms and endoscopic manifestations of mesenteric artery FMD may appear similar to CD and BD. Hence, it is difficult to make a clear clinical diagnosis and proceed with treatment. Mesenteric artery FMD often requires surgical pathology to confirm its diagnosis. For patients who suffer from this disorder, surgery may be the best choice to improve the patient's quality of life. [ABSTRACT FROM AUTHOR]

Background: Hydrogen/potassium ATPase β (ATP4B) is a proton pump acting an essential role in gastric acid secretion. This study aimed to investigate the diagnostic performance of ATP4B and its biological role in tumor progression in gastric cancer. Methods: The correlations between ATP4B expression level and clinicopathologic parameters, as well as the relevance of ATP4B expression with overall survival were assessed. The functional roles of ATP4B in gastric cancer were verified by gain- and loss-of-function cell models and tumor xenograft models. The possible downstream effects of ATP4B were analyzed by iTRAQ-based quantitative proteomics analysis. Results: A dramatic decrease in ATP4B was associated with malignant transformation in gastric mucosa lesions and correlated with poor differentiation. Restoration of ATP4B expression in gastric cancer cells significantly suppressed cell proliferation, cell viability, migration, invasion, tumorigenicity and induced apoptosis, whereas ATP4B silencing exerted the opposite effects. Mechanistically, we found a quality control on mitochondrial metabolism and functions in ATP4B-overexpression GC cells. Conclusions: Our data suggest that decreasing ATP4B is an indicator for gastric mucosa malignant transformation and GC aggressive phenotype and it plays an inhibitory role in gastric cancer as a tumor suppressor via regulating mitochondrial metabolism and apoptosis pathway. [ABSTRACT FROM AUTHOR]

Sliding wear tests of a titanium-matrix composite (TMC) against M35 steel were performed at room temperature. To improve the wear performance of the TMC, an attempt was made to induce a protective tribofilm by artificially supplying nanoscale materials, viz. multilayer graphene (MLG), Fe2O3, and their composite and mixture, onto the sliding tracks. Irrespective of the load, MLG or Fe2O3 additives could hardly improve the wear performance of the TMC because of a lack of load-bearing or lubricant capacity. However, the MLG/Fe2O3 nanocomposite and MLG + Fe2O3 mechanical mixture could effectively improve the wear performance. Interestingly, a critical load existed, at or below which extremely low wear loss and friction coefficient were obtained, which can be attributed to the formation of a protective tribofilm. [ABSTRACT FROM AUTHOR]

Background: Liao ning virus (LNV) is a member of the genus Seadornavirus, family Reoviridae and has been isolated from kinds of vectors in Asia and Australia. However, there are no systematic studies describe the molecular genetic evolution and migration of LNVs. With the development of bioinformatics, viral genetic data combining the information of virus isolation time and locations could be integrated to infer the virus evolution and spread in nature. Methods: Here, a phylogenetic and phylogeographic analysis using Bayesian Markov chain Monte Carlo simulations was conducted on the LNVs isolated from a variety of vectors during 1990–2014 to identify the evolution and migration patterns of LNVs. Results: The results demonstrated that the LNV could be divided into 3 genotypes, of which genotype 1 mainly composed of LNVs isolated from Australia during 1990 to 2014 and the original LNV strain (LNV-NE97–31) isolated from Liaoning province in northern China in 1997, genotype 2 comprised of the isolates all from Xinjiang province in western China and genotype 3 consisted the isolates from Qinghai and Shanxi province of central China. LNVs emerged about 272 years ago and gradually evolved into three lineages in the order genotype 1, genotype 2 and genotype 3. Following phylogeographic analysis, it shows genotype 1 LNVs transmitted from Australia (113°E-153°E,10°S-42°S) to Liaoning province (118°E-125°E,38°N-43°N) in Northeast Asian continent then further spread across the central part of China to western China (75°E-95°E,35°N-50°N). Conclusion: LNVs were initially isolated from Liaoning province of China in the Northeast Asia, however, the present study revealed that LNVs were first appeared in Australia in the South Pacific region and transmitted to mainland China then rapidly spread across China and evolved three different genotypes. The above results suggested that LNV had the characteristics of long-distance transmission and there were great genetic diversity existed in the LNV population. Notably, current information of 80 strains of LNVs are limited. It is of great importance to strengthen the surveillance of LNVs to explore its real origin in nature and monitoring of the LNVs' population variation and maintain vigilance to avoid LNV breaking through the species barrier and further clarify its relationship to human and animal infection. [ABSTRACT FROM AUTHOR]

Highlights • Inspired by the inter generative mechanism in the brain, we propose to use deep convolutional neural network to extract the high-level semantic information of stereoscopic images. • Considering the binocular visual characteristics, we propose to mimic the interaction process by fusing the high-level semantic features of left and right views. Abstract In this paper, we propose a no-reference (NR) quality assessment method for stereoscopic images by deep convolutional neural network (DCNN). Inspired by the internal generative mechanism (IGM) in the human brain, which shows that the brain first analyzes the perceptual information and then extract effective visual information. Meanwhile, in order to simulate the inner interaction process in the human visual system (HVS) when perceiving the visual quality of stereoscopic images, we construct a two-channel DCNN to evaluate the visual quality of stereoscopic images. First, we design a Siamese Network to extract high-level semantic features of left- and right-view images for simulating the process of information extraction in the brain. Second, to imitate the information interaction process in the HVS, we combine the high-level features of left- and right-view images by convolutional operations. Finally, the information after interactive processing is used to estimate the visual quality of stereoscopic image. Experimental results show that the proposed method can estimate the visual quality of stereoscopic images accurately, which also demonstrate the effectiveness of the proposed two-channel convolutional neural network in simulating the perception mechanism in the HVS. [ABSTRACT FROM AUTHOR]

Three-dimensional (3D) graphene aerogel and its composite with interconnected pores have aroused continuous interests in energy storage field owning to its large surface area and hierarchical pore structure. Herein, we reported the preparation of 3D nitrogen-doped graphene/polyaniline (N-GE/PANI) composite foam for supercapacitive material with greatly improved electrochemical performance. The 3D porous structure can allow the penetration and diffusion of electrolyte, the incorporation of nitrogen doping can enhance the wettability of the active material and the number of active sites with electrolyte, and both the N-GE and PANI can ensure the high electrical conductivity of total electrode. Moreover, the synergistic effect between N-GE and PANI materials also play an important role on the electrochemical performance of electrode. Therefore, the as-prepared composite foam could deliver a high specific capacitance of 528 F g −1 at 0.1 A g −1 and a high cyclic stability with 95.9% capacitance retention after 5000 charge-discharge cycles. This study provides a new idea on improving the energy storage capacity of supercapacitors by using 3D graphene-based psedocapacitive electrode materials. [ABSTRACT FROM AUTHOR]

The development of accurate, reliable and low cost devices for glucose detection is one of the most important scientific and technological hotspots. In this study, we proposed a unique one-step thermal synthesis strategy to synthesize nickel (Ni) nanoparticles modified graphene (GE) sheets by using metal-oleate complex as the precursor and sodium sulfate as a template. With the assistance of sodium sulfate particles, Ni nanoparticles with particle size of about 99.2 nm were homogenously anchored on graphene nanosheets in the product. The electrochemical behavior of the nanocomposite towards enzyme-free glucose oxidation was investigated systematically by cyclic voltammetry and amperometric measurements. The results reveal that the GE/Ni nanocomposite exhibited excellent electrocatalytic response to glucose with a wide linear range of 0.01–2.5 mM, a low detection limit of 0.79 μM, and a high sensitivity of 388.4 μA mM −1 cm −2 . In addition, no significant interference was observed from potential interference species. The simple, efficient and scalable synthesis and the excellent catalytic performance endow the GE/Ni nanocomposite great potential application in enzymeless glucose detection. [ABSTRACT FROM AUTHOR]

We propose a structural similarity (SSIM)-motivated two-pass variable bit rate control algorithm for High Efficiency Video Coding. Given a bit rate budget, the available bits are optimally allocated at group of pictures (GoP), frame, and coding unit (CU) levels by hierarchically constructing a perceptually uniform space with an SSIM-inspired divisive normalization mechanism. The Lagrange multiplier $\lambda$ , which controls the tradeoff between perceptual distortion and bit rate, is adopted as the GoP level complexity measure. To derive $\lambda$ , Laplacian distribution-based rate and perceptual distortion models are established after the first pass encoding, and the target bits are dynamically allocated by maintaining a uniform Lagrange multiplier level for each GoP through $\lambda$ equalization. Within each GoP, rate control is further performed at frame and CU levels based on SSIM-inspired divisive normalization, aiming to transform the prediction residuals into a perceptually uniform space. Experiments show that the proposed scheme achieves high accuracy rate control and superior rate-SSIM performance, which is further verified by subjective visual testing. [ABSTRACT FROM PUBLISHER]

Visible-light-driven photocatalysis as a green technology has attracted intense interest due to its potential applications in environmental remediation. However, the poor visible light utilization and low electron-hole separation efficiency of photocatalysts largely limited their practical application. In this work, a new ternary visible-light driven photocatalyst of g-C 3 N 4 /CDs/AgBr has been prepared by the introduction of carbon dots (CDs) onto the surface of g-C 3 N 4 , followed by in-situ growth of AgBr nanoparticles on CDs-modified g-C 3 N 4 nanosheets. The g-C 3 N 4 /CDs/AgBr nanocomposite exhibits excellent photocatalytic efficiency for organic pollutant degradation, which is about 4.0, 5.3 and 2.3 times higher than that of AgBr, g-C 3 N 4 and g-C 3 N 4 /AgBr, respectively. The result indicates the introduction of CDs into g-C 3 N 4 /AgBr can largely improve the photocatalytic activity since CDs act as the light absorber and the electron mediator between g-C 3 N 4 and AgBr, which effectively promote the separation of photogenerated charge carriers and the utilization of visible light. Moreover, the photocatalytic activity of g-C 3 N 4 /CDs/AgBr has no obvious decrease after four photodegradation cycles, demonstrating a high photocatalytic stability. This study highlights the potential application of highly efficient CDs decorated photocatalysts in waste water purification. [ABSTRACT FROM AUTHOR]

In this work, cuprous oxide (Cu2O) hollow cubes were synthesized on reduced graphene oxide (RGO) nanosheets by a facile one-pot refluxing approach. The as-prepared Cu2O/RGO nanocomposites were characterized by X-ray diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy, and transmission electron microscopy. It was revealed that Cu2O with a well-defined hollow cubic morphology is homogeneously dispersed on the surface of RGO nanosheets. The electrocatalytic properties of Cu2O/RGO nanocomposites for glucose oxidation were investigated by cyclic voltammetry and chronoamperometry. It was found that the constructed glucose sensor has a wide linear range of 0.01–9.0 mM (R2 = 0.996) with a high sensitivity of 813.713 μA cm−2 mM−1 and a low detection limit of 0.44 μM based on signal/noise = 3. Compared to bare Cu2O and previously reported Cu2O-based glucose sensors, the as-prepared Cu2O/RGO nanocomposite glucose sensor showed remarkably enhanced electrocatalytic activity. In addition, the electrode also exhibited an excellent anti-interference ability. The excellent electrocatalytic performance together with simple and low-cost preparation makes Cu2O/RGO nanocomposites attractive for glucose sensor application. [ABSTRACT FROM AUTHOR]

In this work, an excellent ternary visible-light all solid Z-scheme photocatalytic heterojunction of g-C 3 N 4 /GO/AgBr has been prepared by the attachment of graphene oxide (GO) to the surface of g-C 3 N 4 , followed by in-situ growth of AgBr nanoparticles on GO sheets. The g-C 3 N 4 /GO/AgBr heterojunction exhibits excellent photocatalytic efficiency for RhB degradation, which is about 17.5, 7.9, 3.5, 4.0 and 2.2 times as high as that of P25, g-C 3 N 4 , AgBr, g-C 3 N 4 /GO and g-C 3 N 4 /AgBr heterojunction, indicating the introduction of GO into the system largely improved the capability of the photocatalysis since GO acted as the charge transmission bridge between g-C 3 N 4 and AgBr. Moreover, the photocatalytic performance of g-C 3 N 4 /GO/AgBr just showed a slight decrease after 4 degradation cycles, demonstrating a high stability of the g-C 3 N 4 /GO/AgBr photocatalyst. The photocatalytic mechanism investigation indicated that O 2 − and h + are the major active species in the photocatalytic process. It is expected that the GO-inserted Z-scheme photocatalytic heterojunction could be applied to practical pollutant degradation. [ABSTRACT FROM AUTHOR]

SnPb-SnAgCu mixed solder joints with Sn-Pb soldering Sn-Ag-Cu Pb-free components are inevitably occurred in the high reliability applications. In this study, the interfacial behaviors in Sn-37Pb and Sn-3.0Ag-0.5Cu mixed solder joints was addressed and compared with Sn-37Pb solder joints and Sn-3.0Ag-0.5Cu solder joints with the influence from isothermal aging and electromigration. Considering the difference on the melting point between Sn-3.0Ag-0.5Cu and Sn-37Pb solder, two mixed solder joints: partial mixing and full mixing between Sn-Pb and Sn-Ag-Cu solders were reached with the peak reflowing temperature of 190 and 250 °C, respectively. During isothermal aging, the intermetallic compound (IMC) layer increased with aging time and its growth was diffusion controlled. There was also no obvious affect from the solder composition on IMC growth. After electromigration with the current density of 2.0 × 10 3 A/cm 2 , Sn-37Pb solder joints showed the shortest lifetime with the cracks observed at the cathode for the stressing time < 250 h. In Sn-3.0Ag-0.5Cu Pb-free solder joints, current stressing promoted the growth of IMC layer at the interfaces, but the growing rate of IMC at the anode interface was far faster than that at the cathode interface. Therefore, there existed an obvious polarity effect on IMC growth in Sn-Ag-Cu Pb-free solder joints. After Sn-37Pb was mixed with Sn-3.0Ag-0.5Cu Pb-free solder, whether the partial mixing or the full mixing between Sn-Pb and Sn-Ag-Cu can obviously depress both the crack formation at the cathode side and the IMC growth at the anode. [ABSTRACT FROM AUTHOR]

Graphene oxide (GO)-AgIO nanocomposites with excellent photocatalytic performance have been prepared through a facile ion-exchange method. The as-prepared samples are characterized by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, and transmission electron microscopy. The GO-AgIO nanocomposites exhibit an enhanced photocatalytic activity in the degradation of organic pollutants as compared to bare AgIO. It is revealed that the introduction of GO can relieve the agglomeration of AgIO particles, enhance the light absorption of the materials, and promote the separation of photoexcited electron-hole pairs. In addition, the possible transfer and separation behaviors of the charge carriers and the photocatalytic mechanism are discussed in detail. The excellent photocatalytic performance makes the GO-AgIO nanocomposites a promising photocatalyst for organic pollutant treatment. [ABSTRACT FROM AUTHOR]

• A motion variation based quality pooling method for 3D video quality assessment. • The method relies on the edge energy information and motion energy information. • Temporal information is effective in estimating monocular energy. The two-stage framework has been widely used in objective image/video quality assessment (IQA/VQA) methods, which includes local quality measurement and global quality pooling. Most of the existing IQA/VQA methods dedicate to local quality degradation modeling. Nevertheless, the significant pooling strategies are often neglected, especially in the quality assessment methods for asymmetrically distorted 3D video sequences. In this paper, motivated by the fact that the perceptual visual information might be affected by the visual masking due to motion suppression, a novel pooling strategy is proposed for visual quality assessment of asymmetrically distorted 3D video sequences by considering the motion variation-based perceptual visual information (MVPVI). In specific, to extract valuable visual information of video sequences, the proposed method computes the motion energy information (MEI) and edge energy information (EEI) by quantifying the frame difference map and the gradient map, respectively. Furthermore, in order to simulate the phenomenon of motion suppression in local motion scenes, where the perceptual information of low-attentional regions might be neglected by the human visual system (HVS), the proposed method first employs the coefficient of variation (CV) to determine the type of motion (local or global) in consecutive frames. Then, the perceptual visual information of the two cases is quantified. Finally, to simulate the role of HVS as an optimal information extractor, the estimated perceptual visual information of each single-view video sequence is used as the weighting factor for the quality pooling of left and right-view video sequences. Extensive comparison experiments conducted on Waterloo-IVC 3D video quality databases demonstrate that the proposed pooling strategy outperforms other relevant pooling strategies, and it achieves better performance than state-of-the-art 3D-IQA/VQA methods when combined with 2D-IQA/VQA methods. [ABSTRACT FROM AUTHOR]