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In this paper, the piezospectroscopic effect for β -Ga2O3, i.e. the spectral band shift in response to strain/stress, has been calibrated by the indentation method using spatially resolved Raman spectroscopy for quantitative stress evaluation of Ga2O3 devices, taking advantage of the crack-tip tensile stress field and the spatial probe deconvolution. A series of Vickers indentation prints were introduced on (010) and ( 2 ˉ 01) Ga2O3 single crystals, and the relationships between observed band shifts and residual stresses were clarified to determine the phonon deformation potentials of the Raman bands. Accordingly, a quantitative analysis of the residual stress field in a Ga2O3 thin film grown on (0001) sapphire by plasma-assisted pulsed laser deposition, which revealed the presence of a gradient of incompletely released stress in the depth direction of the film, is shown as an example. [ABSTRACT FROM AUTHOR]

Objectives: Treatment methods of local residual or recurrent hepatocellular carcinoma (HCC) after thermal ablation are limited. Therefore, our study aimed to explore the efficacy and prognostic factors of 125I brachytherapy for local residual or recurrent lesion after thermal ablation. Methods: A total of 114 patients with 212 local residual or recurrent HCC tumors after thermal ablation underwent 125I brachytherapy. Local progression-free survival (LPFS) and prognostic factors were analyzed by Kaplan–Meier curves and the Cox model. Results: After a 6-month follow-up, the percentage of patients who achieved complete response (CR), partial response (PR), and stable disease (SD) was 57%, 13.2%, and 5.2%, respectively. The 1-, 2-, and 3-year LPFS rates were 58.7%, 50.0%, and 41.2%, respectively. Portal vein tumor thrombus (PVTT) (p = 0.03), the number of intrahepatic tumors (p = 0.01), and AFP level (p = 0.02) were independent risk factors for local tumor progression (LTP). The median LPFS in patients without PVTT (22 months) was much longer compared to those with PVTT (10 months). The median LPFS in patients with less than three intrahepatic lesions improved from 17 to 24 months. The median LPFS was only 5 months in the high AFP group, but was prolonged with a decrease in AFP level (24 months). No severe complications were recorded. All complications were controllable and treatable. Conclusions: CT-guided 125I brachytherapy was a safe and effective treatment for patients with local residual or recurrent HCC after thermal ablation to improve local control rate. Key points: 125I brachytherapy is a treatment for locally recurrent HCC after ablation. 125I brachytherapy combined with ablation may improve tumor control. Vascular invasion, multiple lesions, and AFP are prognostic risk factors. 125I brachytherapy is a safe method with a curative effect. [ABSTRACT FROM AUTHOR]

Objective. The arrhythmia identification method based on the U-net has the potential for fast application. The RR-intervals have been proven to improve the performance of single-heartbeat identification methods. However, because both the heartbeats number and location in the input of the U-net are unfixed, the approach based on the U-net cannot use RR-intervals directly. To solve this problem, we proposed a novel method. The proposed method also can identify heartbeats of four classes, including non-ectopic (N), supraventricular ectopic beat (SVEB), ventricular ectopic beat (VEB), and fusion beat (F). Approach. Our method consists of the pre-processing and the two-stage identification framework. In the pre-processing part, we filtered input signals with a band-pass filter and created the auxiliary waveforms by RR-intervals. In the first stage of the framework, we designed a network to handle input signals and auxiliary waveforms. We proposed a masking operation to separate the input signal into two signals according to the result of the network. The first signal contains heartbeats of SVEB and VEB. The second signal includes heartbeats of N and F. The second stage consists of two networks and can further identify the heartbeats of SVEB, VEB, N, and F from these two signals. Main result. We validated our method on the MIT-BIH arrhythmia database with the inter-patient model. For classes N, SVEB, VEB, and F, our approach achieved F1 scores of 98.26, 68.61, 95.99, and 47.75, respectively. Significance. Our method not only can effectively utilize RR intervals but also can identify multiple arrhythmias. [ABSTRACT FROM AUTHOR]

In this study, microstructural variation of hydroxyapatite (HAp) ceramics upon thermal treatment in air at different temperatures was investigated by x-ray diffraction patterns, Raman and x-ray photoelectron spectroscopies. The results revealed a significant dependence of the microstructure of nonstoichiometric HAp on temperature, because of the competition between hydroxylation and different kinds of dehydroxylation at different temperatures, and a gradual increase in material hardness with annealing temperature because of structural reconstruction. In summary, a suitable thermal treatment can effectively tailor microstructure and defect contents, as well as chemical composition and mechanical hardness of HAp ceramics. [ABSTRACT FROM AUTHOR]

Objective. Muscle artifacts (MA) and electrode motion artifacts (EMA) in electrocardiogram (ECG) signals lead to a large number of false alarms from cardiac diagnostic systems. To reduce false alarms, it is necessary to improve the performance of the diagnostic algorithm in noisy environments by removing excessively noisy signals. However, existing methods focus on signal quality assessment and contain too many artificial features. Here, we present a novel method to flexibly eliminate noisy signals without any artificial features. Approach. Our method contains an improved lightweight deep neural network (DNN) to capture the signal portions damaged by EMA and MA, uses the sample entropy to quantize noisy portions, and discards those portions that exceed a defined threshold. Our method was tested in conjunction with Pan-Tompkins (PT), Filter Bank (FB), and 'UNSW' R-peak detection algorithms along with two heartbeat classification algorithms on datasets synthesized from the MIT-BIH Noise Stress Test Database, the China Physiological Signal Challenge 2018 Database and the MIT-BIH Arrhythmia Database. Main results. For PT R-peak detection algorithms, the sensitivity (Se) increased noticeably from 89.01% to 99.42% in the synthesized datasets with a signal-to-noise ratio of 6 dB. With the same datasets, the Se of the FB algorithm increased about 9.29%, and a 3.64% increase occurred in the Se of the 'UNSW' algorithm. For heartbeat classification algorithms, the overall F1-score increased about 6% in the synthesized one-heartbeat datasets. It is the first study to utilize a DNN to capture noisy segments of the ECG signal. Significance. Too many false alarms can cause alarm fatigue. Our method can be utilized as the preprocessing before signal analysis, thereby reducing false alarms from the ECG diagnostic systems. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this paper is to develop an improved adhesion model to better reproduce the low adhesion condition of the anti-skid control for rail vehicles under braking condition. Design/methodology/approach: In view of the low adhesion characteristics for rail vehicles under braking conditions, the Polach adhesion model was improved based on the sliding power and sliding energy. The wheel–rail low adhesion model suitable for braking condition was given. The analysis of braking anti-skid control under emergency braking condition was carried out through the co-simulation, and compared with the test data; the effectiveness and practicability of the improved low adhesion model were verified. Findings: The results showed that the improved adhesion model is simple and efficient and the parameters involved are less, and it can be directly applied to the real-time simulation of anti-skid control in the process of train braking. Originality/value: This paper can provide a theoretical reference for the reasons of change and improvement of adhesion between wheel and rail caused by the adjustment of braking force under anti-skid control, which can fulfill a need to the study of sliding energy on the contact surface, the removal effect of pollutants on the wheel–rail surface and the improvement and recovery of adhesion caused. Peer review: The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-07-2020-0244/ [ABSTRACT FROM AUTHOR]

To investigate the effects of tributyrin supplementation in soybean oil (SO)-based diet, three equal-protein (50%) and equal-lipid (12%) experimental diets were formulated: the fish oil (FO) diet, the SO diet, and the tributyrin (TB) diet with 0.20% tributyrin supplemented in the SO-based diet. Each diet was randomly fed to triplicate tanks with 20 fish (initial weight, 9.00 ± 0.02 g) per tank (300 L). Fish were fed to apparent satiation twice daily for 56 days. The whole body, muscle, and intestine tissue samples were collected for analysis. The results indicated that tributyrin partly reversed the final body weight (TB [39.92 ± 0.33 g] versus SO [35.12 ± 0.55 g]) and feed efficiency rate (TB [0.99 ± 0.01] versus SO [0.92 ± 0.01]) decrease and the whole body crude lipid content increase, caused by the replacement of dietary FO by SO. A significant increase in the polyunsaturated fatty acid proportion was observed in the muscle tissue of fish fed the tributyrin diet. The improvement of growth performance mediated by tributyrin supplementation may be attributed to the significant improvement of the intestinal morphology, as indicated by the morphology structure section and molecular parameters. Dietary tributyrin may decrease the SO-induced pro-inflammatory response, characterized by significantly decreased expression of a pro-inflammatory gene (IL-6) and significantly increased expression of an anti-inflammatory gene (IL-10) (P < 0.05). In conclusion, dietary 0.20% tributyrin supplementation in the SO-based diet improved growth performance, affected muscle fatty acid composition, and improved intestinal histology structure in the juvenile yellow drum. [ABSTRACT FROM AUTHOR]

Polarized Raman spectroscopy is applied to non-destructively unfold the variation of crystallographic orientation in wurtzitic GaN films that occurred during their growth on (0001)-oriented sapphire substrates as a function of growth conditions. Variations of polarized Raman spectra were clearly observed at different locations along the growth direction by systematically performing line scans on cross sections of different film/substrate systems. Such variations showed a strong dependence on the type of buffer layer, deposition temperature, and reactor pressure. The observed trends suggested the occurrence of inhomogeneous lateral growth of GaN films near the buffer layer and a continuous adjustment of the structure of the tilted-grown epilayer during the growth process until reaching the expected stable structure. The large elastic/thermal mismatch, which could not be fully relaxed by the effect of the buffer layer, resulted in a non-uniform distribution of residual strain. Such strain, mainly stored at the interface, gradually relaxed by the occurrence of tilting and twisting of the crystal cells along the film growth direction: a process that spontaneously occurred minimizing the strain energy stored in the film/substrate system. Varying reactor pressure caused a variation of residual strain in the epilayer and thus a different adjustment of the GaN microstructure during the growth process. Relatively homogenous GaN films with a low density of dislocations could be achieved on patterned sapphire substrates, despite the presence of crystallographic tilting of the film. [ABSTRACT FROM AUTHOR]

Raman spectroscopy was applied with a high spectral resolution to a structural study of Influenza (type A) virus before and after its inoculation into Madin–Darby canine kidney cells. This study exploits the fact that the major virus and cell constituents, namely DNA/RNA, lipid, and protein molecules, exhibit peculiar fingerprints in the Raman spectrum, which clearly differed between cells and viruses, as well as before and after virus inoculation into cells. These vibrational features, which allowed us to discuss viral assembly, membrane lipid evolution, and nucleoprotein interactions of the virus with the host cells, reflected the ability of the virus to alter host cells' pathways to enhance its replication efficiency. Upon comparing Raman signals from the host cells before and after virus inoculation, we were also able to discuss in detail cell metabolic reactions against the presence of the virus in terms of compositional variations of lipid species, the formation of fatty acids, dephosphorylation of high‐energy adenosine triphosphate molecules, and enzymatic hydrolysis of the hemagglutinin glycoprotein. [ABSTRACT FROM AUTHOR]

The effect of yttria content on structural and thermal stability of zirconia in yttria-stabilized zirconia (YSZ) polycrystalline ceramics was systematically investigated by Raman spectroscopy and X-ray photoelectron spectroscopy. Taking advantage of an experimentally retrieved linear dependence of Raman bandwidth on yttria content, Raman imaging was applied as an effective tool in examining the local yttrium distribution in YSZ ceramics and its relationship with environmentally driven polymorphic transformation. A significant variation of monoclinic fraction with yttria content and temperature was found and interpreted according to a newly proposed model, which takes into account the change in lattice hydroxyl and oxygen vacancies and the possible formation of stable defect complexes. [ABSTRACT FROM AUTHOR]

Structural variations and phase stability in 3 mol% yttria stabilized tetragonal zirconia (3Y-TZP) subjected to long-term aging at room temperature and thermal treatments in air were investigated by Raman and X-ray photoelectron spectroscopies, and compared with previous cases obtained by hydrothermal treatments. The results revealed a significant difference in the kinetics of zirconia polymorphic transformation in different environments due to the critical roles played by surface and lattice hydroxyl defects. Thermal treatments in air of long-term stored 3Y-TZP revealed a gradual recovery to tetragonal phase due to the ocurrence of dehydroxylation, while thermal treatments of pristine 3Y-TZP caused tetragonal-to-monoclinic polymorphic transformation at low temperature, but then an inverse transformation at higher tempertures due to a competition of hydroxylation and dehydroxylation. Treatments of 3Y-TZP in different environments were found to lead to distinct paths of off-stoichiometric chemistry, including hydroxylation, hydroxyl migration, surface reconstruction, and dehydroxylation during the treatments. [ABSTRACT FROM AUTHOR]

Electro-optical detection systems face numerous challenges due to the complexity and difficulty of targeting controls for "low, slow and tiny" moving targets. In this paper, we present an optimal model of an advanced n-step adaptive Kalman filter and gyroscope short-term integration weighting fusion (nKF-Gyro) method with targeting control. A method is put forward to improve the model by adding a spherical coordinate system to design an adaptive Kalman filter to estimate target movements. The targeting error formation is analyzed in detail to reveal the relationship between tracking controller feedback and line-of-sight position correction. Based on the establishment of a targeting control coordinate system for tracking moving targets, a dual closed-loop composite optimization control model is proposed. The outer loop is used for estimating the motion parameters and predicting the future encounter point, while the inner loop is used for compensating the targeting error of various elements in the firing trajectory. Finally, the modeling method is substituted into the disturbance simulation verification, which can monitor and compensate for the targeting error of moving targets in real time. The results show that in the optimal model incorporating the nKF-Gyro method with targeting control, the error suppression was increased by up to 36.8% compared to that of traditional KF method and was 25% better than that of the traditional nKF method. [ABSTRACT FROM AUTHOR]

Oxide-dispersion- and hard-particle-strengthened (ODS) laser-cladded single-layer multi-tracks with a Ni-based alloy composition with 20 wt.% μm-WC particles and 1.2 wt.% nano-Y2O3 addition were produced on ultra-high-strength steel in this study. The investigation of the composite coating designed in this study focused on the reciprocating friction and wear workpiece surface under heavy load conditions. The coating specimens were divided into four groups: (i) Ni-based alloy, nano-Y2O3, and 2 μm-WC (2 μm WC-Y/Ni); (ii) Ni-based alloy with added 2 μm-WC (2 μmWC/Ni); (iii) Ni-based alloy with added 80 μm-WC (80 μmWC/Ni); and (iv) base metal ultra-high-strength alloy steel 30CrMnSiNi2A. Four conclusions were reached: (1) Nano-Y2O3 could effectively inhibit the dissolution of 2 μm-WC. (2) It can be seen from the semi-space dimensionless simulation results that the von Mises stress distribution of the metal laser composite coating prepared with a 2 μm-WC particle additive was very uniform and it had better resistance to normal impact and tangential loads than the laser coating prepared with the 80 μm-WC particle additive. (3) The inherent WC initial crack and dense stress concentration in the 80 μm-WC laser coating could easily cause dislocations to accumulate, as shown both quantitatively and qualitatively, resulting in the formation of micro-crack nucleation. After the end of the running-in phase, the COF of the 2 μm-WC-Y2O3/Ni component samples stabilized at the minimum of the COF of the four samples. The numerical order of the four COF curves was stable from small to large as follows: 2 μm-WC-Y2O3/Ni, 2 μm-WC/Ni, 80 μm-WC/Ni, and 30CrMnSiNi2A. (4) The frictional volume loss rate of 2 μm-WC-Y2O3/Ni was 1.3, which was significantly lower than the corresponding values of the other three components: 2.4, 3.5, and 13. [ABSTRACT FROM AUTHOR]

A spatially resolved cathodoluminescence piezospectroscopic analysis is attempted for the high-resolution evaluation of the stress field developed ahead of the tip of an equilibrium crack propagating in a semiconductor. GaN was selected for this assessment as a paradigm semiconductor material. Quantitative measurements of in-plane luminescence probe response function (PRF) were preliminarily performed at different acceleration voltages upon scanning across a straight and atomically sharp interface between GaN and gold metal. Then, based on the knowledge of PRF, the convoluting effect due to the finite size of the electron probe could be corrected and an improved plot of the crack-tip stress field could be retrieved by a computer-aided data restoration procedure. The crack-tip stress intensity factor KI obtained by the cathodoluminescence piezospectroscopic method was compared with that obtained on the same crack path according to high-resolution measurements of crack-tip opening displacement. This study not only shows that a nanometer-scale spatial resolution can be experimentally achieved in a stress analysis of semiconductor materials but also that a stress data treatment based on experimental PRF is a viable approach to greatly reduce the error involved with the finite size of the electron probe. [ABSTRACT FROM AUTHOR]

The piezospectroscopic (PS) effect was studied in an intergrowth bismuth layer-structure ferroelectric ceramic Bi5TiNbWO15 according to a micro-Raman spectroscopic evaluation. By using a ball-on-ring flexure configuration, a biaxial stress was generated in a Bi5TiNbWO15 plate-like specimen and in situ collected Raman spectra were acquired and analyzed under several loading conditions. As the observed spectral line contained signals arising from the whole illuminated in-depth region, the laser probe information was deconvoluted (by means of an in-depth probe response function obtained according to the defocusing method) in order to deduce biaxial PS coefficients for the three Raman bands of Bi5TiNbWO15 located at 763, 857, and 886 cm-1, respectively. The biaxial PS coefficients of these bands were derived to be -1.74±0.16, -2.51±0.16, and -2.64±0.31 cm-1/GPa, respectively, and should be referred to the c axis of the Bi5TiNbWO15 crystal. [ABSTRACT FROM AUTHOR]

Abstract In this work, vanadium pentoxide and reduced graphene oxide (rGO) nanocomposites were synthesized by a simple solvothermal process with subsequent annealing treatment. The study revealed that introducing with a small amount of graphene has a great influence on the V 2 O 5 nanostructure. Adding an appropriate amount of graphite oxide (GO) powder resulted in the formation of rGO substrates via the solvothermal process, which acted as a good dispersant to impede the aggregation of V 2 O 5 blocks. As a result, an ideal morphology of porous V 2 O 5 nanorods dispersed on rGO substrates could be observed. In particular, the nanocomposites possessed a high specific capacitance of 450.5 F/g at a current density of 0.5 A/g, retaining 73.3% of the initial capacitance even at 10 A/g. Symmetric supercapacitors assembled with these electrode materials achieved an excellent energy density of 33.5 Wh/Kg at a power density of 425.6 W/Kg, which is higher than most reported symmetric supercapacitors. Especially, the potential window of the supercapacitor is 0–1.7 V in an electrolyte of 5 M LiNO 3 , which is also distinctive in the symmetric supercapacitor group. Graphical abstract When the mass of the introduced GO is about 7.1% f, most of V 2 O 5 exists in the form of porous nanorods with the diameter varying from 30 nm to 200 nm. A symmetric supercapacitor based on the V 2 O 5 electrodes possesses a high energy density of 33.5 Wh/Kg at a power density of 425.6 W/Kg. Unlabelled Image Highlights • Porous V 2 O 5 nanorods were dispersed on rGO substrates. • The V 2 O 5 electrode possesses a high specific capacitance of 450.5 F/g. • Symmetric supercapacitors achieved an energy density of 33.5 Wh/Kg. [ABSTRACT FROM AUTHOR]

In this paper, Raman spectral mappings were carried out on Vickers indentation prints introduced on DLC films prepared with different substrate bias voltages (SBV). The mapping results showed clear differences in the intensity ratio, I D / I G , and band shifts for D and G peaks in samples fabricated with and without applying SBV. These spectral characteristics arose from the cumulative effect of a compressive (residual) stress field and structural alterations including sp2 and sp3 carbon disorder upon generation of the indentation print. Additional quantitative stress analyses, which employed spectral line scans on the film cross sections, revealed clear differences in magnitude for the compressive stresses stored in the films, as well as in-depth structural variations resulting from different SBV being applied during fabrication. An increasing level of residual compressive stress in the DLC films with increasing SBV may directly contribute to the observed decreased adhesion to the substrates and to the increased Vickers hardness. Unlabelled Image • Raman mappings were conducted around Vickers indentation prints on DLC films. • Applying SBV showed clear influences on I D / I G , and band shifts for D and G peaks. • Stress and structural alterations influence sp2 and sp3 carbon disorder. • Residual stresses and in-depth structural variations varied with SBV. • Residual compressive stress influenced film adhesion and Vickers hardness. [ABSTRACT FROM AUTHOR]

Here we report a novel and simple two-step method to fabricate polyaniline, which consists of two successive low-temperature (−20 °C, frozen) and near-room temperature (30 °C) periods. Melting of the frozen part and solute migration mainly drives polymerization. It is proved that the two-step method is an efficient way to fabricate polyaniline with a bimodal morphology composed of coral-like structure with thorns and interconnected nanowire structure. The mechanism of formation of such bimodal morphology is discussed in detail. Optimized polyaniline prepared by this method showed an excellent electrochemical energy storage performance, with a specific capacitance of 689 F g -1  at 1 A g −1 and a good retention rate of 89% (613 F g −1 ) at 10 A g −1 . Symmetric cells based on it show an energy density of 12.6 Wh kg −1 at a power density of 188.3 W kg −1 . In summary, this work provides a new way to fabricate polyaniline for supercapacitor applications. [ABSTRACT FROM AUTHOR]

In this paper, the influence of transition metals on phase stability of zirconia in 3 mol% Y 2 O 3 doped tetragonal zirconia polycrystals (3Y-TZP) in hydrothermal environments was reported. 3Y-TZP with and without stainless-steel or CoCr metal stains on the sample surface were subjected to different isothermal treatments in water vapor, and their respective monoclinic fractions were quantified by confocal Raman spectroscopy. The outputs of these spectroscopic experiments revealed transition metals conspicuously could stabilize the tetragonal zirconia polymorph in the monolithic zirconia, possibly due to the occurrence of off-stoichiometric chemistry in the presence of metal stains. [ABSTRACT FROM AUTHOR]

Over the next two decades, a strong demographic demand for arthroplastic devices coupled with a decreased efficacy of antibiotics has been predicted to result in an exponential increase in the number of periprosthetic joint infections (PJIs). Advanced strategies are therefore required to improve the local peri-implant immune response and curb the pathogenic events of bacterial adhesion and biofilm formation. The use of biomaterials that autonomously counter infections is one approach to improve orthopedic outcomes. Using conventional molecular biology characterization methods and advanced Raman spectroscopy, this study examined the bacteriostatic response of two bioceramic materials commonly employed as prosthetic implants: zirconia-toughened alumina (ZTA) and silicon nitride (Si3N4). Unlike the ZTA, it was found that non-oxide Si3N4 possesses an inherently anti-infective surface chemistry, which acts in a responsive way against bacterial loading. The mechanistic details of its behavior are elucidated. Non-oxide bioceramics appear to be promising, but their full development requires a transitional approach that integrates the fundamental biochemical concepts with clinical outcomes. [ABSTRACT FROM AUTHOR]

Purpose: The purposes of this study were to document novel Raman spectroscopic findings in femoral heads affected by osteonecrosis and to identify molecular structure differences based on aetiology.Methods: We obtained 13 femoral heads with osteonecrosis from 13 different patients who underwent total hip arthroplasty. Comparisons were made between the viable zones of each femoral head examined. The samples were scanned with X-ray micro-CT for structural mapping and a central coronal section slab was prepared for Raman spectroscopy and histological analyses. Raman spectra were collected at different locations, including the viable and necrotic zones of the femoral head, using a highly spectrally resolved Raman microprobe.Results: Significant alterations in the spectral morphology in the high wavenumber region were found, with a pronounced inhibition of peculiar lipid signals in the frequency interval 2851 ~ 2890 cm-1 and at ~ 1750 cm-1. The necrotic zone in steroid-associated osteonecrosis showed an increase in the ratio of lipid-related bands to protein-related bands, while alcohol-associated osteonecrosis exhibited a decrease in this ratio.Conclusions: We systematically found a decrease in Raman intensity for sphingomyelin and phenylalanine fingerprint bands in the necrotic zones, and these differences may be related to the etiology of osteonecrosis. [ABSTRACT FROM AUTHOR]

Spectrally resolved cathodoluminescence measurements of Bi5-xLaxTiNbWO15 (x=0–1.50) ceramics at room temperature showed three distinct luminescence bands located at about 380, 502, and 660 nm, respectively, which were tentatively assigned to F+ center, oxygen vacancy-related defect and octahedron structure-related luminescence center, respectively. These assignments could be made in light of electron irradiation experiments with different exposure times. Bands related to oxygen vacancies were clearly enhanced by lanthanum doping, indicating that charge compensation occurred by the substitution of Bi for La3+ in perovskitelike structured intergrowth ferroelectrics. We observed that, for contents of La3+ x>0.75, La3+ ions entered the [Bi2O2]2+ layer according to a doping mechanism which is briefly discussed in this letter. [ABSTRACT FROM AUTHOR]

Human pluripotent stem cells (hPSCs) promise a foreseeing future for regeneration medicine and cell replacement therapy with their abilities to produce almost any types of somatic cells of the body. The complicated immunogenicity of hPSC derivatives and context dependent responses in variable transplantations greatly hurdle the practical application of hPSCs in clinic. Especially for applications of hPSCs, induction of immune tolerance at the same time increases the risks of tumorigenesis. Over the past few years, thanks to the progress in immunology and practices in organ transplantation, endeavors on exploring strategies to induce long term protection of allogeneic transplants have shed light on overcoming this barrier. Novel genetic engineering techniques also allow to precisely cradle the immune response of transplantation. Here we reviewed the current understanding on immunogenicity, and efforts have been attempted on inducing immune tolerance for hPSC derivatives, with extra focus on modifying the graft cells. We also glimpse on employing cutting-edge genome editing technologies for this purpose, which will potentially endow hPSC derivatives with the nature of wide spectrum drugs for therapy. [ABSTRACT FROM AUTHOR]

In this work, kelp-like structured NiCo 2 S 4 -C-MoS 2 composite electrode materials for supercapacitors were successfully synthesized by a facile hydrothermal and solvothermal method. Due to the synergistic effect of the mixture of graphene-like MoS 2 nanosheets, highly conductive carbon and NiCo 2 S 4 , the composite materials exhibited superior electrochemical performance: specific capacitance of 1601 F/g at a current density of 0.5 A/g, and rate performance of 61% at 10 A/g. Furthermore, an asymmetric supercapacitor (ASC), fabricated by using the NiCo 2 S 4 -C-MoS 2 composite and activated carbon (AC) as positive and negative electrodes, respectively, showed a high energy density of 27.7 Wh/kg at a power density of 400 W/kg (it retained 14.4 Wh/kg at power density up to 8 kW/kg). After 1000 charge-discharge cycles at 2 A/g, the ASC device still maintained 60% of its initial capacitance. The outstanding performance of the NiCo 2 S 4 -C-MoS 2 composite indicates its great potential for applications in high-performance energy storage systems. [ABSTRACT FROM AUTHOR]

To make unmanned surface vehicles that are better applied to the field of environmental monitoring in inland rivers, reservoirs, or coasts, we propose a global path-planning algorithm based on the improved A-star algorithm. The path search is carried out using the raster method for environment modeling and the 8-neighborhood search method: a bidirectional search strategy and an evaluation function improvement method are used to reduce the total number of traversing nodes; the planned path is smoothed to remove the inflection points and solve the path folding problem. The simulation results reveal that the improved A-star algorithm is more efficient in path planning, with fewer inflection points and traversing nodes, and the smoothed paths are more to meet the actual navigation demands of unmanned surface vehicles than the conventional A-star algorithm. [ABSTRACT FROM AUTHOR]

Exploitation of the toughening effect induced by polymorphic phase transformation of zirconia in zirconia-toughened alumina (ZTA) requires the composite being properly designed and carefully manufactured. A sound algorithm for predicting phase stability along with strict control over manufacturing steps are required in order to prevent possible in vivo surface degradation or implant fracture. This paper is the first in a series of three monographs, which aim at: (i) statistically comparing the in vitro / in vivo phenomenology of surface-metastability for currently marketed ZTA femoral heads; (ii) refining pre-existing theoretical models for predicting in vivo zirconia phase metastability via the use of accelerated in vitro ageing experiments; and, (iii) providing a rationale for the mechanism(s) involved with the observed in vivo surface metastability. This initial paper of a series of three, which specifically deals with item (i), shows discrepancies between the levels of polymorphic phase transformation detected in ZTA retrievals and in vitro predictions, and attempts a phenomenological analysis of the reasons behind such discrepancies. Moreover, marked inhomogeneities are also found among as-manufactured components through different years of production. The phenomenology of retrievals' data suggests key roles for both the presence of metallic stain and the initial value of monoclinic volume fraction. [ABSTRACT FROM AUTHOR]

In this paper, an updated analytical model for the kinetics of the tetragonal to monoclinic ( t → m ) polymorphic transformation in ZTA composites for hip joints is proposed and discussed. The model builds upon the so-called Mehl-Avrami-Johnson (MAJ) description of transformation kinetics, which combines two overlapping processes: nucleation of monoclinic sites, and their successive growth. Dependencies on two specific factors are introduced in the model, namely the initial fraction of monoclinic polymorph as received from the manufacturer, and the presence of different types of transition-metal stains ( e.g. , Ti, CoCr, and Fe) on the ZTA surface. These two factors were studied because clear indications of their potential roles on the environmental stability of implantable ZTA components were found in previous phenomenological analyses of retrievals. Nucleation and growth of monoclinic domains are two key processes whose interplay decides the actual kinetics of the overall transformation process according to two main parameters: an apparent activation energy value function of time and temperature, and a nuclei growth exponent. These parameters were clearly altered by the presence of transition metal contamination, whose effect was incorporated into the model to explain exacerbations of surface degradation. In accordance with a general analytical description of transformation kinetics for isothermal or isochronal evolutions in terms of time and temperature, the modified model of the MAJ description assesses the effect of the initial monoclinic fraction. The updated model has been validated using systematic in vitro experiments, and appears to partly reconcile in vitro and in vivo data of t → m transformation discrepancies in ZTA hip components. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the potential molecular mechanisms through which dietary soybean lecithin inclusion affects the growth, development, and intestinal morphology of yellow drum (Nibea albiflora) larvae. Four types of equal-protein and equal-lipid content microdiets (MDs) were formulated with graded levels of phospholipids (%, dry matter): 3.84 (SL0), 6.71 (SL4), 9.38 (SL8), and 12.21 (SL12). Larvae (25 days post-hatching; initial body weight 5.0 mg) were fed four replicates of MDs or Artemia nauplii (live prey) daily for 28 days. We found that dietary soybean lecithin inclusion promoted the growth performance, dorsal fin appearance rate, and body-color transition to juvenile-type in yellow drum larvae. Intestinal histological analysis confirmed that dietary supplementation with soybean lecithin prevented the appearance of vacuoles in enterocytes and increased the goblet cells as well as the perimeter ratio, muscular thickness, and mucosal fold height of the mid-intestinal tissue. Transmission and scanning electron microscopic analyses of the mid-intestine revealed that insufficient soybean lecithin inclusion decreased microvillus density and length and secretory vesicle production. Unique molecular identifier - RNA sequencing revealed that the improvement in intestinal morphology caused by dietary optimal soybean lecithin inclusion could be attributed to increased fatty acid β-oxidation and subsequent energy production in the intestinal tissue. Compared with the larvae fed with MDs, those fed with live prey experienced body-color transition retardation and a considerable fecal adhesion rate. The significantly decreased expression of genes encoding chemokines could attribute to the high fecal adhesion rate. Collectively, the findings of this study demonstrated the necessity of dietary soybean lecithin for the growth, development, and promotion of mid-intestinal morphology during the N. albiflora larval stage. The promotion of mid-intestinal morphology was likely caused by the resulting increased energy supply to enterocytes. Weaning larvae from live prey to MDs promoted intestinal health and development performance. • Soybean lecithin inclusion promoted growth performance and development. • Soybean lecithin inclusion promoted mid-intestinal morphology. • Live prey led to larval retarded body-color transition and intestinal health problems. [ABSTRACT FROM AUTHOR]

In situ diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy was used to study the reaction of dimethyl ether (DME) carbonylation to methyl acetate (MAc). Methoxyl and acetyl groups were observed in situ, confirming the reaction mechanistic proposal. DME adsorption bands on Si OH, Al OH and SiOHAl (Brønsted acid sites) groups were identified respectively. The effect of temperature and pressure on acetyl formation and side reactions were systematically studied. It was found that methoxyls formed by DME chemisorbed on Brønsted acid sites could be observed above 433 K. High pressure and appropriate temperature interval promoted the formation of acetyls. Side reactions, DME transformed into olefins and then into cokes, were favored at low pressure and high temperature. Carbonylation reactions on catalysts with acid sites only in 8MR side pockets and 12MR main channels of mordenite (samples noted as HMOR-SP and HMOR-MC) were conducted by in situ DRIFT spectroscopy and catalytic testing. Pyridine molecules adsorbed in 12MR main channels resulted in the low utilization of acid sites in 8MR side pockets. The synthesis rate of MAc on HMOR-SP was stable but lower. HMOR-MC presented the lowest MAc synthesis rate with the production of coke, which was also observed in DRIFT spectra. [ABSTRACT FROM AUTHOR]

Background/Aims: Our previous in silico analysis revealed potential synergy in the activities of micro(mi)RNAs in myocardial infarction. The present study investigated whether miR-1 and -21 act synergistically to protect against cardiomyocytes apoptosis. Methods: Cell survival was analyzed with cell viability assay; apoptosis was detected by flow cytometry, terminal deoxynucleotidyl transferase dUTP nick end labeling, and the caspase-3 activity assay; and protein expression level was determined by western blotting. Results: MiR-1:miR-21 and several other miRNA pairs were evaluated for their potentially synergistic effects against myocardial hypoxia in neonatal rat ventricular cardiomyocytes. Lower combination indices suggested that miRNA pairs acted synergistically to inhibit apoptosis; miR-1 and -21 jointly blocked hypoxia-induced cardiomyocytes apoptosis. Moreover, combined application of miR-1 and -21 activated Akt and blocked hypoxia-induced upregulation of p53 in these cells. Conclusion: MiR-1 and -21 exert synergistic effects against hypoxia-induced cardiomyocytes apoptosis. These results provide a basis for the development of combined miRNA-based therapeutics to treat cardiovascular diseases. [ABSTRACT FROM AUTHOR]

Solid oxide fuel cells (SOFCs) as alternatives for energy conversion have exhibited some unique advantages such as wide fuel flexibility, high energy efficiency and exhaust heat. An innovative composite cathode for SOFCs consisting of a high conductive La 0.7 Sr 0.3 CuO 3 − δ (LSCu) electrode backbone infiltrated by nano and Ba 0.5 Sr 0.5 Co 0.8 Fe 0.2 O 3 − δ (BSCF) particles with high electro-catalytic activity has been successfully fabricated by a simple solution infiltration process. The effect of BSCF nano catalyst on the electrochemical activity and stability of LSCu cathode was investigated and the inherent oxygen reduction reaction (ORR) mechanism is discussed. The polarization resistance is 0.043 Ω cm 2 for 15 wt.% BSCF infiltrated LSCu cathode, and is reduced ~ 92.6% to that pure LSCu (0.58 Ω cm 2 ) at 700 °C. The short term stability demonstrates that the electrochemical activity can be further improved in the first period about 40 h at 700 °C. After operated for 70 h, the electrochemical performance of the composite cathode became stable. A conductive scaffold (e.g. LSCu) modified with a highly catalytic nano particles (e.g. BSCF) is an attractive approach to fabricate cathodes with high electrochemical performance and stability. [ABSTRACT FROM AUTHOR]

Background: Acting on many mRNAs allows the power of a single miRNA to modulate multiple pathophysiological phenotypes. One question is whether versatile miRNAs exist in the pathological scenarios of myocardial infarction (MI) and heart failure (HF). Methods: A hypergeometric analysis, in combination with network-based functional analyses, was performed on the available human protein interaction and miRNA-gene association data to highlight versatile miRNAs among the significantly dysregulated miRNAs in MI and HF. In vivo, mice models of MI and HF were then established to investigate whether dysregulated expression be undertaken by versatile miRNA identified here. Results: Systematic analyses really identified the previously validated miRNAs that have been verified of multiple important roles in MI and HF, demonstrating method effectiveness. By using this means, we innovatively revealed the vital role of miR-7 in maintaining the dynamic balance of protein interactions and its obvious overexpression in MI and HF that implies pathological involvement. Functional experiments are definitely needed for further revealing its potential influences on MI- or HFled myocardial injury. Conclusion: Our results have implications not only for the coming miRNA-based strategy in treating MI and HF but also for further understanding on gene regulation by miRNAs in human heart. [ABSTRACT FROM AUTHOR]

Diamond-like carbon (DLC) films represent promising surface treatments for biomedical implants. In this paper, using Raman and X-ray photoelectron spectroscopies, we analyzed the effects of secondary phases present in ZrO 2 substrates on the structure of DLC films fabricated by plasma-based ion implantation and deposition method, and the structural stability of the films in response to applied indentation prints. The results revealed oxygen incorporation in DLC films from the oxide substrates during deposition, and a clear dependence of sp3 carbon content on the oxygen fraction of the substrate and on gas pressure. Moreover, a pronounced structural distortion of the DLC films at the film/substrate interface was observed, which resulted from polymorphic transformation on the zirconia surface during deposition, while a pronounced change in Raman spectral morphology of carbon induced by structural alterations could also be observed around the indentation prints. The findings clearly pointed at the need to take into considerations the structural alterations of the DLC film structure at the interface associated with interfacial defects and film adhesion, especially for biomedical applications that involve surface loading. [Display omitted] • Effects of secondary phases in ZrO 2 substrates on the DLC structure were clarified. • Structural stability of the films in response to applied loads was investigated. • Oxygen incorporation in DLC films depended on both substrate and gas pressure. • Phase transformation of zirconia contributed to structural distortion of DLC films. • Structural alterations were induced around the indentation prints on the DLC films. [ABSTRACT FROM AUTHOR]

The Raman spectroscopic method has quantitatively been applied to the analysis of local crystallographic orientation in both single-crystal hydroxyapatite and human teeth. Raman selection rules for all the vibrational modes of the hexagonal structure were expanded into explicit functions of Euler angles in space and six Raman tensor elements (RTE). A theoretical treatment has also been put forward according to the orientation distribution function (ODF) formalism, which allows one to resolve the statistical orientation patterns of the nm-sized hydroxyapatite crystallite comprised in the Raman microprobe. Close-form solutions could be obtained for the Euler angles and their statistical distributions resolved with respect to the direction of the average texture axis. Polarized Raman spectra from single-crystalline hydroxyapatite and textured polycrystalline (teeth enamel) samples were compared, and a validation of the proposed Raman method could be obtained through confirming the agreement between RTE values obtained from different samples. [ABSTRACT FROM AUTHOR]

A kind of composite materials consisting of nano-sized Nafion resin homogeneously dispersed in a high-surface silica matrix was prepared by sol–gel method and used as catalysts in the vapor-phase carbonylation reaction of dimethoxymethane for production of methylmethoxy acetate. These composite catalysts showed much higher catalytic activity in comparison with the original pure Nafion resin catalyst. The remarkable improvement of catalytic performance was due to the increased accessibility of acid sites of Nafion resin in the composite catalysts. The contents of Nafion-H resin and silica precursors were found to have a great influence on the structure of the composite, resulting in different catalytic activity during DMM carbonylation reactions. Furthermore, the comparison of the composite catalysts with high-silica H-Y and H-Beta zeolite catalysts demonstrated that the excellent catalytic performance is closely related to the higher acid strength and larger pores of Nafion-silica composite materials. [ABSTRACT FROM AUTHOR]

Three types of commercially available ultra-high molecular weight polyethylene (UHMWPE) acetabular cups currently used in total hip arthroplasty have been studied by means of Raman micro-spectroscopy to unfold the microstructural modification induced by the oxidative degradation after accelerated aging with and without lipid absorption. The three investigated materials were produced by three different manufacturing procedures, as follows: irradiation followed by remelting, one-step irradiation followed by annealing, 3-step irradiation and annealing. Clear microstructural differences were observed in terms of phase contents (i.e. amorphous, crystalline and intermediate phase fraction). The three-step annealed material showed the highest crystallinity fraction in the bulk, while the remelted polyethylene is clearly characterized by the lowest content of crystalline phase and the highest content of amorphous phase. After accelerated aging either with or without lipids, the amount of amorphous phase decreased in all the samples as a consequence of the oxidation-induced recrystallization. The most remarkable variations of phase contents were detected in the remelted and in the single-step annealed materials. The presence of lipids triggered oxidative degradation especially in the remelted polyethylene. Such experimental evidence might be explained by the highest amount of amorphous phase in which lipids can be absorbed prior to accelerated aging. The results of these spectroscopic characterizations help to rationalize the complex effect of different irradiation and post-irradiation treatments on the UHMWPE microstructure and gives useful information on how significantly any single step of the manufacturing procedures might affect the oxidative degradation of the polymer. [ABSTRACT FROM AUTHOR]

In this paper, polarized Raman spectroscopy is applied to quantitatively assess crystallographic alteration and interfacial residual stress with a micron-scale resolution in highly 〈0 0 0 1〉 oriented (textured) polycrystalline wurtzitic AlN films grown on (0 0 1)-oriented Si substrates. Raman selection rules for the wurtzite structure of AlN were explicitly put forward and a set of Raman tensor elements determined from experimentally retrieved angular dependences of Raman band intensities upon in-plane rotation measurements. An appreciably high degree of homogeneity in the AlN film (i.e., with respect to both in-plane and out-of-plane Euler angles, retrieved according to the proposed spectroscopic algorithm) could be observed in spectral line scans randomly selected on the cross-section of the film/substrate system. These characterizations indicated negligible structural alterations, such as grain tilting and twisting during film growth. However, a non-uniform stress distribution in the AlN film along the film thickness direction was found, which remained stored during manufacturing of the AlN film. A quite remarkable magnitude of compressive residual stress (∼−1.5 GPa) could be measured at the film/substrate interface. Finally, a Raman (non-destructive) statistical characterization of the film system in terms of micromechanical homogeneity by spectral surface mapping is presented, which provides a prompt overall view of the film quality. The proposed procedure should generally be applicable in crystallographic and micromechanical quality control of electronic film devices exhibiting a Raman spectrum. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRNAs) have been shown to be promising biomarkers in predicting cancer prognosis. However, inappropriate or poorly optimized processing and modeling of miRNA expression data can negatively affect prediction performance. Here, we propose a holistic solution for miRNA biomarker selection and prediction model building. This work introduces the use of a neural network cascade, a cascaded constitution of small artificial neural network units, for evaluating miRNA expression and patient outcome. A miRNA microarray dataset of nasopharyngeal carcinoma was retrieved from Gene Expression Omnibus to illustrate the methodology. Results indicated a nonlinear relationship between miRNA expression and patient death risk, implying that direct comparison of expression values is inappropriate. However, this method performs transformation of miRNA expression values into a miRNA score, which linearly measures death risk. Spearman correlation was calculated between miRNA scores and survival status for each miRNA. Finally, a nine-miRNA signature was optimized to predict death risk after nasopharyngeal carcinoma by establishing a neural network cascade consisting of 13 artificial neural network units. Area under the ROC was 0.951 for the internal validation set and had a prediction accuracy of 83% for the external validation set. In particular, the established neural network cascade was found to have strong immunity against noise interference that disturbs miRNA expression values. This study provides an efficient and easy-to-use method that aims to maximize clinical application of miRNAs in prognostic risk assessment of patients with cancer. [ABSTRACT FROM AUTHOR]

NiCo-LDH-rGO cathodes and Fe 2 O 3 -rGO anodes (specific capacity of 1073F g−1 at 1A g−1) were prepared using the co-precipitation method. The NiCo-LDH-rGO//Fe 2 O 3 -rGO electrochemical capacitors offered an energy density of 108 Wh/kg at a power density of 884 W/kg. [Display omitted] • A novel co-precipitation method was used to prepare NiCo-LDH-rGO cathodes and Fe 2 O 3 -rGO anodes. • The Fe 2 O 3 -rGO anodes exhibited an excellent specific capacitance of 1073 F g−1 at a current density of 1 A g−1. • The device made of NiCo-LDH-rGO cathodes and Fe 2 O 3 -rGO anodes provided an energy density of 108 Wh/kg. Faraday-type electrode materials and devices for electrochemical capacitors have been widely investigated. However, their applications are severely limited by the preparation method and cost of electrode materials. In this work, high-performance electrochemical capacitors were successfully assembled using Fe 2 O 3 -decorated reduced graphene oxide (rGO) nanocomposites and NiCo-Layered Double Hydroxides (LDH) as the anode and cathode, respectively. An easy and efficient approach (the modified precipitation method) for the large-scale fabrication was used to prepare Fe 2 O 3 and NiCo-LDH, supported by rGO sheets, respectively. The anode material, Fe 2 O 3 -rGO, exhibited an excellent specific capacitance (C sp) of 1073 F g−1 at a current density of 1 A g−1 and a retention rate of 92 % at 10 A g−1, while the NiCo-LDH-rGO cathode material provided a C sp of 1850 F g−1 at 1 A g−1 and maintained 84 % at 10 A g−1. The effective combination of these electrodes for the NiCo-LDH-rGO//Fe 2 O 3 -rGO electrochemical capacitors resulted in an excellent energy density of 108 Wh/kg at a power density of 884 W/kg, with remarkable cycling stability (80 % after 1000 cycles at 10 A g−1). We believe that this work, including the proposed method and electrode materials, will advance the further development and commercialization of electrochemical capacitors. [ABSTRACT FROM AUTHOR]

In the current study, high-temperature stability was investigated in two types of zirconia ceramics stabilized with two different additives, namely, calcia and yttria. The evolutions of structure and oxygen-vacancy-related defects upon annealing in air were investigated as a function of temperature by combining X-ray diffractometry with Raman, X-ray photoelectron and cathodoluminescence spectroscopies. We systematically characterized variations in the concentration of oxygen vacancies and hydroxyl groups during thermal treatments and linked them to structural alterations and polymorphic transformation. With this approach, we clarified how the combined effects of different dopants and temperature impacted on structural development and on the thermal stability of the oxygen-vacancy-related defect complex. [ABSTRACT FROM AUTHOR]

Abstract: Raman spectroscopy and scanning electron microscopy, combined with the Vickers indentation method, were applied to analyze the fracture behavior of a thin (i.e., 1μm in thickness) aluminum nitride (AlN) film deposited on a (001)Si substrate. A series of indentations were introduced in the AlN/Si system with applying gradually increasing loads, and the stress intensity factor, K R, stored at the tip of cracks propagated from the indentation corners was determined according to the shift of selected Raman bands from wurtzitic AlN in response to the crack-tip residual stress field. A steeply rising crack resistance curve was found in the AlN film, starting from an intrinsic toughness, K I0 =0.6MPam1/2, for crack initiation up to K R ≅5MPam1/2 (at a crack length of ~120μm). Such rising R-curve behavior was attributed to the presence of a compressive residual stress field stored in the AlN film. The results obtained by Raman spectroscopy were consistently supported by direct crack opening displacement measurements in a scanning electron microscope. [Copyright &y& Elsevier]

Despite a large amount of microRNAs (miRNAs) have been validated to play crucial roles in human biology and disease, there is little systematic insight into the nature and scale of the potential synergistic interactions executed by miRNAs themselves. Here we established an integrated parameter synergy score to determine miRNA synergy, by combining the two mechanisms for miRNA-miRNA interactions, miRNA-mediated gene co-regulation and functional association between target gene products, into one single parameter. Receiver operating characteristic (ROC) analysis indicated that synergy score accurately identified the gene ontology-defined miRNA synergy (AUC = 0.9415, p<0.001). Only a very small portion of the random miRNA-miRNA combinations generated potent synergy, implying poor expectancy of widespread synergy. However, targeting more key genes made two miRNAs more likely to act synergistically. Compared to other miRNAs, miR-21 was a highly exceptional case due to frequent appearance in the top synergistic miRNA pairs. This result highlighted its essential role in coordinating or strengthening physiological and pathological functions of other miRNAs. The synergistic effect of miR-21 and miR-1 were functionally validated for their significant influences on myocardial apoptosis, cardiac hypertrophy and fibrosis. The novel approach established in this study enables easy and effective identification of condition-restricted potent miRNA synergy simply by concentrating the available protein interactomics and miRNA-target interaction data into a single parameter synergy score. Our results may be important for understanding synergistic gene regulation by miRNAs and may have significant implications for miRNA combination therapy of cardiovascular disease. [ABSTRACT FROM AUTHOR]

A quantitative polarized Raman analysis of ferroelectric grain/domain orientation in LiSbO3 (LS-modified) (K0.5Na0.5)NbO3 (KNN) ceramics is presented, based on the analysis of the complex orientation dependence in space of their Raman-active modes. Complete sets of Raman tensor elements of Ag, and Eg phonon modes for orthorhombic/tetragonal structures of KNN have been determined. Through this spectroscopic algorithm, quantitative information could be extracted in terms of three Euler angles in space for KNN samples consisting of mixed phases, thus enabling quantitative visualization of the local distribution of grains/domains in the solid angle. As an application of the method, we quantitatively examined the unknown crystallographic grain orientation patterns on the surfaces of pure KNN and of KNN-0.05LS ceramics. These two samples were useful to clarify a polymorphic phase transition from the orthorhombic to the tetragonal phase taking place in the LS-modified KNN system. Thus, we demonstrated that polarized Raman spectroscopy is a valuable and efficient tool for nondestructive three-dimensional assessments of grain/domain orientation in ferroelectric materials with complex polymorphic structures. We believe that the data shown here represent a typical scenario encountered in grain/domain orientation assessments of piezoelectric perovskites. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Objective. Electrocardiogram (ECG) signals are easily polluted by various noises which are likely to have adverse effects on subsequent interpretations. Research on model lightweighting can promote the practical application of deep learning-based ECG denoising methods in real-time processing. Approach. Firstly, grouped convolution and conventional convolution are combined to replace the continuous conventional convolution in the model, and the depthwise convolution with stride is used to compress the feature map in the encoder modules. Secondly, additional identity connections and a local maximum and minimum enhancement module are designed, which can retain the detailed information and characteristic waveform in the ECG waveform while effectively denoising. Finally, we develop knowledge distillation in the experiments, which further improves the ECG denoising performance without increasing the model complexity. The ground-truth ECG is from The China Physiological Signal Challenge (CPSC) 2018, and the noise signal is from the MIT-BIH Noise Stress Test Database (NSTDB). We evaluate denoising performance using the signal-to-noise ratio (SNR), the root mean square error (RMSE) and the Pearson correlation coefficient (P). We use the floating point of operations (FLOPs) and parameters to calculate computational complexity. Main Results. Different data generation processes are used to conduct experiments: group 1, group 2 and group 3. The results show that the proposed model (U Lde -net) can improve SNRs by 10.30 dB, 12.16 dB and 12.61 dB; reduce RMSEs by 9.88 × 10−2, 20.63 × 10−2 and 15.25 × 10−2; and increase P s by 14.77 × 10−2, 27.74 × 10−2 and 21.32 × 10−2. Moreover, the denoising performance after knowledge distillation is further improved. The U Lde -net has parameters of 6.9 K and FLOPs of 6.6 M, which are much smaller than the compared models. Significance. We designed a lightweight model, but also retain adequate ECG denoising performance. We believe that this method can be successfully applied to practical applications under time or memory limits. [ABSTRACT FROM AUTHOR]

An analytical procedure has been developed according to basic principles of electro-stimulated luminescence spectroscopy aimed at quickly visualizing with high spatial resolution the domain texture developed in tetragonal BaTiO3 (BT) materials. In the first part of the paper, the relative intensity of the cathodoluminescence (CL) emission has been systematically collected from different crystallographic planes of BT single-crystal and modeled as a function of anisotropic crystal properties. In this context, an analytical expression has been put forward for quantitatively describing the response function of the CL probe, which links the intensity emission to refractive indexes and absorption coefficients pertaining to different planes of the perovskitic crystal. In the second part of the paper, the CL method is applied to visualize with nanometer-scale resolution the domain texture developed in a polycrystalline BT sample. This study demonstrates that CL spectroscopy is a valuable and efficient tool for the assessment of domain orientation in ferroelectric materials. The CL method possesses both wide-range screening capacity and the scanning flexibility of conventional scanning electron microscopy, coupled with a spatial resolution that is comparable with that obtainable by scanning probe microscopy techniques. [ABSTRACT FROM AUTHOR]

[Display omitted] • Analytical algorithms were proposed for fast determining amylose content in rice. • Linear and branched polysaccharide structures were characterized and compared. • Vadiation of the new algorithm was made by comparing with colorimetry method. Analytical algorithms based on Raman spectroscopy are proposed for the determination of amylopectin and amylose concentrations in polished white rice, and applied to characterize and compare linear and branched polysaccharide structures in nine different types of Japanese rice. A selected algorithm used symmetric bending vibrations of the C O C glycosidic linkage from a relatively narrow spectral zone between 830 and 895 cm−1. It specifically compared the intensity of Raman signals from two types of bending common to both starch components (C1-O-C5 and C1-O-C4 at 868 and 855 cm−1, respectively) and that at the branch point peculiar to amylopectin (C1-O-C6 at 844 cm−1). Raman data were confronted with data collected by conventional amylose-iodine colorimetry method. Consistency was found between Raman and colorimetric methods over the entire series of tested rice cultivars, thus validating the newly proposed spectroscopic algorithm. The amylose content of the tested rice species broadly varied between 1.2 and 20.4%. The proposed Raman algorithm allows fast and nondestructive determination of amylose content in rice with minimal sample preparation. These characteristics might be key in the development of portable Raman devices capable to promptly screen polysaccharides in different rice cultivars with respect to their interannual and plantation-related fluctuations. [ABSTRACT FROM AUTHOR]

Abstract: Confocal Raman piezo-spectroscopy was applied to the non-destructive evaluation of residual stresses as they develop in a chemical-vapor-deposited Al2O3 coating on a Si3N4 ceramic substrate. According to a selected confocal configuration of the optical probe, with its focal plane set to in-depth scan the sample, the residual stress could be measured at various depths along the thickness of both coating and substrate. The residual stresses stored in the Al2O3 coating layer were measured using both the Cr3+ fluorescence band, located at 14,400cm−1 (R1), and the Al2O3 Raman band at 417cm−1. When the R1 fluorescence band was used, no variation could be resolved for the residual stress along the coating depth direction; in contrast, a clear in-depth stress distribution was observed when the 417cm−1 Raman band was used. The minimum stress magnitude was located at the coating external surface and the maximum at the coating/substrate interface. Given the high transparency of the Al2O3 coating, the residual stress field stored within the Si3N4 substrate could also be measured as a function of depth (according to the piezo-spectroscopic shift of the 206cm−1 Raman band of Si3N4). A deconvolution procedure of confocal spectra was proposed, which is based on the knowledge of the probe response functions of both coating and substrate materials. Laser probe deconvolution enabled us to retrieve the actual in-depth stress distribution from the stress distribution experimentally observed by defocusing experiments. [Copyright &y& Elsevier]

Abstract: Currently, fuel cells are receiving more and more attention as the most promising new power generation technology, and fuel processing by the mixed reforming of liquid hydrocarbons (MRL) with water and oxygen is regarded as a desirable way for fuel cells. In this paper, we developed a new mixed reforming method for hydrogen production by combining a dense ceramic membrane Ba0.5Sr0.5Co0.8Fe0.2O3−δ (BSCFO) with a catalyst LiLaNiO/γ-Al2O3 in a membrane reactor and reforming a simulated gasoline. During a 500-h long-term test at optimized reaction conditions, all the components in the simulated gasoline converted completely, and around 90% selectivity of CO, around 95% selectivity of H2 and around 8.0mLcm−2 min−1 oxygen permeation flux were achieved. This provides a new optional way of hydrogen production for fuel cells. [Copyright &y& Elsevier]

Abstract: Fuel cells are recognized as the most promising new power generation technology, but hydrogen supply is still a problem. In our previous work, we have developed a LiLaNiO/γ-Al2O3 catalyst, which is excellent not only for partial oxidation of hydrocarbons, but also for steam reforming and autothermal reforming. However, the reaction needs pure oxygen or air as oxidant. We have developed a dense oxygen permeable membrane Ba0.5Sr0.5Co0.8Fe0.2O3 which has an oxygen permeation flux around 11.5ml/cm2 min at reaction conditions. Therefore, this work is to combine the oxygen permeable membrane with the catalyst LiLaNiO/γ-Al2O3 in a membrane reactor for hydrogen production by mixed reforming of heptane. Under optimized reaction conditions, a heptane conversion of 100%, a CO selectivity of 91–93% and a H2 selectivity of 95–97% have been achieved. [Copyright &y& Elsevier]