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Background The purple photosynthetic bacterium Rhodopseudomonas palustris has been widely applied to enhance the therapeutic effects of traditional Chinese medicine using novel biotransformation technology. However, comprehensive studies of the R. palustris biotransformation mechanism are rare. Therefore, investigation of the expression patterns of genes involved in metabolic pathways that are active during the biotransformation process is essential to elucidate this complicated mechanism. Results To promote further study of the biotransformation of R. palustris , we assembled all R. palustris transcripts using Trinity software and performed differential expression analysis of the resulting unigenes. A total of 9725, 7341 and 10,963 unigenes were obtained by assembling the alpha-rhamnetin-3-rhamnoside - treated R. palustris (RPB) reads, control R. palustris (RPS) reads and combined RPB&RPS reads, respectively. A total of 9971 unigenes assembled from the RPB&RPS reads were mapped to the nr, nt, Swiss-Prot, Gene Ontology (GO), Clusters of Orthologous Groups (COGs) and Kyoto Encyclopedia of Genes and Genomes (KEGG) ( E -value <0.00001) databases using BLAST software. A total of 3360 unique differentially expressed genes (DEGs) in RPB versus RPS were identified, among which 922 unigenes were up-regulated and 2438 were down-regulated. The unigenes were mapped to the KEGG database, resulting in the identification of 7676 pathways among all annotated unigenes and 2586 pathways among the DEGs. Some sets of functional unigenes annotated to important metabolic pathways and environmental information processing were differentially expressed between the RPS and RPB samples, including those involved in energy metabolism (18.4% of total DEGs), carbohydrate metabolism (36.0% of total DEGs), ABC transport (6.0% of total DEGs), the two-component system (8.6% of total DEGs), cell motility (4.3% of total DEGs) and the cell cycle (1.5% of total DEGs). We also identified 19 transcripts annotated as hydrolytic enzymes and other enzymes involved in ARR catabolism in R. palustris . Conclusion We present the first comparative transcriptome profiles of RPB and RPS samples to facilitate elucidation of the molecular mechanism of biotransformation in R. palustris . Furthermore, we propose two putative ARR biotransformation mechanisms in R. palustris . These analytical results represent a useful genomic resource for in-depth research into the molecular basis of biotransformation and genetic modification in R. palustris . [ABSTRACT FROM AUTHOR]

A novel composite cathode consisting of A-site disordered Pr 0.5 Ba 0.5 MnO 3−δ (PBM) and Er 0.4 Bi 1.6 O 3 (ESB) is developed for solid oxide fuel cells (SOFCs) with ceria-bismuth bilayer electrolyte. Based on Sm 0.075 Nd 0.075 Ce 0.85 O 2−δ |ESB (SNDC|ESB) bilayer structured film, the single cell NiO-SNDC|SNDC|ESB|ESB-PBM achieves an encouraging performance with the maximum power density (MPD) of 994 mW cm −2 and an interfacial polarization resistance (R p ) of 0.027 Ω cm 2 at 650 °C. Although a possible reaction between ESB and PBM has been identified in the cathode, the ascendant electrochemical performance including the very high fuel cell performance and R p obtained here can demonstrate that the novel cobalt-free composite cathode ESB-PBM is a preferable alternative for ceria-bismuth bilayer electrolyte high performance low temperature SOFCs (HPLT-SOFCs) and the interfacial reaction in the cathode seems not to be detrimental to the electrochemical performance. [ABSTRACT FROM AUTHOR]

Accurate characterization of visual attributes such as spiculation, lobulation, and calcification of lung nodules in computed tomography (CT) images is critical in cancer management. The characterization of these attributes is often subjective, which may lead to high inter- and intra-observer variability. Furthermore, lung nodules are often heterogeneous in the cross-sectional image slices of a 3D volume. Current state-of-the-art methods that score multiple attributes rely on deep learning-based multi-task learning (MTL) schemes. These methods, however, extract shared visual features across attributes and then examine each attribute without explicitly leveraging their inherent intercorrelations. Furthermore, current methods treat each slice with equal importance without considering their relevance or heterogeneity, which limits performance. In this study, we address these challenges with a new convolutional neural network (CNN)-based MTL model that incorporates multiple attention-based learning modules to simultaneously score 9 visual attributes of lung nodules in CT image volumes. Our model processes entire nodule volumes of arbitrary depth and uses a slice attention module to filter out irrelevant slices. We also introduce cross-attribute and attribute specialization attention modules that learn an optimal amalgamation of meaningful representations to leverage relationships between attributes. We demonstrate that our model outperforms previous state-of-the-art methods at scoring attributes using the well-known public LIDC-IDRI dataset of pulmonary nodules from over 1,000 patients. Our model also performs competitively when repurposed for benign-malignant classification. Our attention modules provide easy-to-interpret weights that offer insights into the predictions of the model. [Display omitted] [ABSTRACT FROM AUTHOR]

• A new internally-mixed aerosol optics scheme was developed. • Artificial neural networks were used to parameterize aerosol optical properties. • The inhomogeneous aerosol model had lower absorption than the well-mixed model. • The optics scheme was evaluated using the Weather Research and Forecasting model. • The impact of particle inhomogeneity was obvious in the planetary boundary layer. A new internally-mixed aerosol optics scheme was developed. Aerosols (organic carbon, sea salt, aerosol water, sulfate, and nitrate) were assumed to be internally mixed with black carbon and soil dust (BC and SD, respectively), both of which are treated as cores. In the SD-containing particles, the particle non-sphericity was incorporated. Aerosol optical properties were computed from the invariant imbedding T-matrix method and the Lorenz–Mie theory and then parameterized using a novel method involving artificial neural networks (ANN). The new scheme was evaluated using the Weather Research and Forecasting (WRF) model. A case study involving East Asia was performed on Dec 3-4, 2010. Compared to uniformly mixed aerosols, inhomogeneous mixed aerosols had lower absorbability and stronger solar backscattering, causing a positive aerosol direct radiative effect (DRE) bias at the surface (3.0 and 2.6 W/m2 for the Sichuan Basin and Northern China, respectively) and negative DRE bias at the top of atmosphere ([TOA], −3.5 and −2.2 W/m2, respectively). Inhomogeneity effects caused a large reduction (up to 0.2K) in the atmospheric warming above the planetary boundary layer (PBL) and caused a northerly anomaly at 850 hPa on the order of 0.3 m/s. The non-sphericity effect was only significant over the Tarim Basin. DREs related to non-sphericity decreased at both the surface and TOA (−1.0 and −0.6 W/m2, respectively) due to stronger extinction. Non-sphericity caused more surface dimming and more solar heating, which had opposite effects on temperature perturbation, producing a more obvious impact within the PBL than in the free atmosphere. [ABSTRACT FROM AUTHOR]

Proton-conducting oxides offer a promising way of lowering the working temperature of solid oxide cells to the intermediate temperate range (500 to 700 °C) due to their better ionic conductivity. In addition, the application of proton-conducting oxides in both solid oxide fuel cells (SOFCs) and sold oxide electrolysis cells (SOECs) provides unique advantages compared with the use of conventional oxygen-ion conducting conductors, including the formation of water at the air electrode site. Since the discovery of proton conduction in some oxides about 30 years ago, the development of proton-conducting oxides in SOFCs and SOECs (the reverse mode of SOFCs) has gained increased attention. This paper briefly summarizes the development in the recent years of R-SOFCs with proton-conducting electrolytes, focusing on discussing the importance of adopting chemically stable materials in both fuel cell and electrolysis modes. The development of electrode materials for proton-conducting R-SOFCs is also discussed. [ABSTRACT FROM AUTHOR]

Understanding the inherent optical properties (IOPs) of coccoliths and coccolithophores is important in oceanic radiative transfer simulations and remote sensing implementations. In this study, the invariant imbedding T-matrix method (II-TM) is employed to investigate the IOPs of coccoliths and coccolithophores. The Emiliania huxleyi ( Ehux ) coccolith and coccolithophore models are built based on observed biometric parameters including the eccentricity, the number of slits, and the rim width of detached coccoliths. The calcification state that specifies the amount of calcium of a single coccolith is critical in the determination of the size–volume/mass relationship (note, the volume/mass of coccoltihs at different calcification states are different although the diameters are the same). The present results show that the calcification state, namely, under-calcification, normal-calcification, or over-calcification, significantly influences the backscattering cross section and the phase matrix. Furthermore, the linear depolarization ratio of the light scattered by coccoliths is sensitive to the degree of calcification, and provides a potentially valuable parameter for interpreting oceanic remote sensing data. The phase function of an ensemble of randomly oriented coccolithophores has a similar pattern to that of individual coccoliths, but the forward scattering is dominant in the coccolithophores due to the large geometric cross sections. The linear depolarization ratio associated with coccolithophores is found to be larger than that for coccoliths as polarization is more sensitive to multiple scattering than the phase function. The simulated coccolithophore phase matrix numerical results are compared with laboratory measurements. For scattering angles larger than 100°, an increase of the phase function with respect to the scattering angle is confirmed based on the present coccolithophore model while the spherical approximation fails. [ABSTRACT FROM AUTHOR]

Abstract: A fundamental problem in remote sensing and radiative transfer simulations involving ice clouds is the ability to compute accurate optical properties for individual ice particles. While relatively simple and intuitively appealing, the conventional geometric-optics method (CGOM) is used frequently for the solution of light scattering by ice crystals. Due to the approximations in the ray-tracing technique, the CGOM accuracy is not well quantified. The result is that the uncertainties are introduced that can impact many applications. Improvements in the Invariant Imbedding T-matrix method (II-TM) and the Improved Geometric-Optics Method (IGOM) provide a mechanism to assess the aforementioned uncertainties. The results computed by the II-TM+IGOM are considered as a benchmark because the II-TM solves Maxwell׳s equations from first principles and is applicable to particle size parameters ranging into the domain at which the IGOM has reasonable accuracy. To assess the uncertainties with the CGOM in remote sensing and radiative transfer simulations, two independent optical property datasets of hexagonal columns are developed for sensitivity studies by using the CGOM and the II-TM+IGOM, respectively. Ice cloud bulk optical properties obtained from the two datasets are compared and subsequently applied to retrieve the optical thickness and effective diameter from Moderate Resolution Imaging Spectroradiometer (MODIS) measurements. Additionally, the bulk optical properties are tested in broadband radiative transfer (RT) simulations using the general circulation model (GCM) version of the Rapid Radiative Transfer Model (RRTMG) that is adopted in the National Center for Atmospheric Research (NCAR) Community Atmosphere Model (CAM, version 5.1). For MODIS retrievals, the mean bias of uncertainties of applying the CGOM in shortwave bands (0.86 and 2.13μm) can be up to 5% in the optical thickness and as high as 20% in the effective diameter, depending on cloud optical thickness and effective diameter. In the MODIS infrared window bands centered at 8.5, 11, and 12μm, biases in the optical thickness and effective diameter are up to 12% and 10%, respectively. The CGOM-based simulation errors in ice cloud radiative forcing calculations are on the order of 10Wm−2. [Copyright &y& Elsevier]

• We propose to use deep learning with few user-clicks to achieve accurate skin lesion segmentation results. • We propose to leverage user-inputs in optimizing the learning of skin lesion characteristics. • We propose hyper-integration modules (HIMs) to iteratively propagate user-input features and skin lesion image features to ensure the appearance of the segmented skin lesions is spatially consistent. • Our method is capable to segment skin lesions that are known to be challenging, such as those with fuzzy boundaries, inhomogeneous textures and low-contrast to the background. • We had consistently better segmentation results on three well-established public datasets (ISBI 2017, ISBI 2016 skin lesion challenge datasets and PH2 dataset). Segmentation of skin lesions is an important step for imaging-based clinical decision support systems. Automatic skin lesion segmentation methods based on fully convolutional networks (FCNs) are regarded as the state-of-the-art for accuracy. When there are, however, insufficient training data to cover all the variations in skin lesions, where lesions from different patients may have major differences in size/shape/texture, these methods failed to segment the lesions that have image characteristics, which are less common in the training datasets. FCN-based semi-automatic segmentation methods, which fuse user-inputs with high-level semantic image features derived from FCNs offer an ideal complement to overcome limitations of automatic segmentation methods. These semi-automatic methods rely on the automated state-of-the-art FCNs coupled with user-inputs for refinements, and therefore being able to tackle challenging skin lesions. However, there are a limited number of FCN-based semi-automatic segmentation methods and all these methods focused on 'early-fusion', where the first few convolutional layers are used to fuse image features and user-inputs and then derive fused image features for segmentation. For early-fusion based methods, because the user-input information can be lost after the first few convolutional layers, consequently, the user-input information will have limited guidance and constraint in segmenting the challenging skin lesions with inhomogeneous textures and fuzzy boundaries. Hence, in this work, we introduce a hyper-fusion network (HFN) to fuse the extracted user-inputs and image features over multiple stages. We separately extract complementary features which then allows for an iterative use of user-inputs along all the fusion stages to refine the segmentation. We evaluated our HFN on three well-established public benchmark datasets – ISBI Skin Lesion Challenge 2017, 2016 and PH2 – and our results show that the HFN is more accurate and generalizable than the state-of-the-art methods, in particular with challenging skin lesions. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: The invariant imbedding T-matrix method (II-TM) is employed to compute the optical properties of randomly oriented ice crystals of various shapes including hexagonal columns, hollow columns, droxtals, bullet rosettes and aggregates. The II-TM is shown to be numerically stable and capable of obtaining the single-scattering properties of hexagonal ice crystals with size parameters up to 150. The 22° and 46° halo peaks in the phase function of compact hexagonal ice crystals begin to emerge at a size parameter of approximately 80 and tend to become insensitive to particle size as the corresponding size parameter approaches 150. Furthermore, the II-TM solutions are shown to be in agreement with their counterparts based on the discrete dipole approximation (DDA) method and the pseudo-spectral time-domain (PSTD) method. In addition, the accuracy of the improved geometric-optics method (IGOM) is examined for randomly oriented hexagonal ice crystal cases over a wide size-parameter range from the resonant to geometric-optics regimes. The II-TM is also used to study the effects of particle surface roughness and internal inclusions on the single-scattering properties of ice particles. [Copyright &y& Elsevier]

Abstract: The conventional Lorenz–Mie theory is generalized for a case when the light source is partially spatially coherent. The influence of the degree of coherence of the incident field on the generalized Mueller matrix and the spectral degree of coherence of the scattered light is analytically studied by using the vector field instead of the scalar field to extend previous results on the angular intensity distribution. The results are compared with the Mueller matrix obtained from the Discrete Dipole Approximation (DDA) method, which is an average over an ensemble of stochastic incident beams. Special attention is paid to the Mueller matrix elements in the backward direction, and the results show some Mueller matrix elements, such as P22, depend monotonically on the coherence length of the incident beam. Therefore, detecting back scattering Mueller matrix elements may be a promising method to measure the degree of coherence. The new formalism is applied to cases of large spherical droplets in water clouds and hexagonal ice crystals in cirrus clouds. The corona and glory phenomena due to spheres and halos associated with hexagonal ice crystals are found to disappear if the incident light tends to be highly incoherent. [Copyright &y& Elsevier]

Two kinds of poly(vinyl alcohol) (PVA)-silica composites were prepared with different methods. One composite was prepared by directly mixing PVA with 80 nm silica nano-particles which were made from tetraethoxysilane (TEOS). The another was obtained by the mixing PVA and hydrolyzed TEOS in the presence of acid-catalyst. The properties of the two PVA/silica hybrids were characterized by means of scanning electron microscopy (SEM), UV-Visible spectroscopy, solubility tests, limiting oxygen index (LOI) test, tensile test and dynamical mechanical analysis (DMA), respectively. The results indicate that PVA-TEOS composites (PT for short) display more transparency than PVA-silica nano-particles hybrids (PS for short). At the same time, The PT composites presented more excellent performance than PS in water resistance, fire resistance and mechanical properties. Moreover, the T of PT increased with increasing TEOS content, while that of PS decreased. [ABSTRACT FROM AUTHOR]

A chemically stable electrolyte structure was developed for proton-conducting SOFCs by using two layers of stable BaZr0.7Pr0.1Y0.2O3−δ to sandwich a highly-conductive but unstable BaCe0.8Y0.2O3−δ electrolyte layer. The sandwiched electrolyte structure showed good chemical stability in both CO2 and H2O atmosphere, indicating that the BZPY layers effectively protect the inner BCY electrolyte, while the BCY electrolyte alone decomposed completely under the same conditions. Fuel cell prototypes fabricated with the sandwiched electrolyte achieved a relatively high performance of 185mWcm−2 at 700°C, with a high electrolyte film conductivity of 4×10−3 Scm−1 at 600°C. [ABSTRACT FROM AUTHOR]

Abstract: The extended boundary condition method (EBCM) and invariant imbedding method (IIM) are two fundamentally different T-matrix methods for the solution of light scattering by nonspherical particles. The standard EBCM is very efficient but encounters a loss of precision when the particle size is large, the maximum size being sensitive to the particle aspect ratio. The IIM can be applied to particles in a relatively large size parameter range but requires extensive computational time due to the number of spherical layers in the particle volume discretization. A numerical combination of the EBCM and the IIM (hereafter, the EBCM+IIM) is proposed to overcome the aforementioned disadvantages of each method. Even though the EBCM can fail to obtain the T-matrix of a considered particle, it is valuable for decreasing the computational domain (i.e., the number of spherical layers) of the IIM by providing the initial T-matrix associated with an iterative procedure in the IIM. The EBCM+IIM is demonstrated to be more efficient than the IIM in obtaining the optical properties of large size parameter particles beyond the convergence limit of the EBCM. The numerical performance of the EBCM+IIM is illustrated through representative calculations in spheroidal and cylindrical particle cases. [Copyright &y& Elsevier]

Abstract: Three terms, “Waterman''s T-matrix method”, “extended boundary condition method (EBCM)”, and “null field method”, have been interchangeable in the literature to indicate a method based on surface integral equations to calculate the T-matrix. Unlike the previous method, the invariant imbedding method (IIM) calculates the T-matrix by the use of a volume integral equation. In addition, the standard separation of variables method (SOV) can be applied to compute the T-matrix of a sphere centered at the origin of the coordinate system and having a maximal radius such that the sphere remains inscribed within a nonspherical particle. This study explores the feasibility of a numerical combination of the IIM and the SOV, hereafter referred to as the IIM+SOV method, for computing the single-scattering properties of nonspherical dielectric particles, which are, in general, inhomogeneous. The IIM+SOV method is shown to be capable of solving light-scattering problems for large nonspherical particles where the standard EBCM fails to converge. The IIM+SOV method is flexible and applicable to inhomogeneous particles and aggregated nonspherical particles (overlapped circumscribed spheres) representing a challenge to the standard superposition T-matrix method. The IIM+SOV computational program, developed in this study, is validated against EBCM simulated spheroid and cylinder cases with excellent numerical agreement (up to four decimal places). In addition, solutions for cylinders with large aspect ratios, inhomogeneous particles, and two-particle systems are compared with results from discrete dipole approximation (DDA) computations, and comparisons with the improved geometric-optics method (IGOM) are found to be quite encouraging. [Copyright &y& Elsevier]

A data library is developed containing the scattering, absorption, and polarization properties of ice particles in the spectral range from 0.2 to 100 μm. The properties are computed based on a combination of the Amsterdam discrete dipole approximation (ADDA), the T-matrix method, and the improved geometric optics method (IGOM). The electromagnetic edge effect is incorporated into the extinction and absorption efficiencies computed from the IGOM. A full set of single-scattering properties is provided by considering three-dimensional random orientations for 11 ice crystal habits: droxtals, prolate spheroids, oblate spheroids, solid and hollow columns, compact aggregates composed of eight solid columns, hexagonal plates, small spatial aggregates composed of 5 plates, large spatial aggregates composed of 10 plates, and solid and hollow bullet rosettes. The maximum dimension of each habit ranges from 2 to 10 000 μm in 189 discrete sizes. For each ice crystal habit, three surface roughness conditions (i.e., smooth, moderately roughened, and severely roughened) are considered to account for the surface texture of large particles in the IGOM applicable domain. The data library contains the extinction efficiency, single-scattering albedo, asymmetry parameter, six independent nonzero elements of the phase matrix ( P11, P12, P22, P33, P43, and P44), particle projected area, and particle volume to provide the basic single-scattering properties for remote sensing applications and radiative transfer simulations involving ice clouds. Furthermore, a comparison of satellite observations and theoretical simulations for the polarization characteristics of ice clouds demonstrates that ice cloud optical models assuming severely roughened ice crystals significantly outperform their counterparts assuming smooth ice crystals. [ABSTRACT FROM AUTHOR]

By modifying the proton conductor BaTbO 3 with the element Co, it is discovered that the solubility of Co in BaTbO 3 is restricted to 20 mol.%, and phase segregations happen for high Co doping concentrations in BaTbO 3. The fabrication of nominal BaTb 0.5 Co 0.5 O 3 results in the in-situ development of the heterostructure cathode composed of BaTb 0.8 Co 0.2 O 3 +BaCoO 3. The critical role of the interface between BaTb 0.8 Co 0.2 O 3 and BaCoO 3 in enhancing fuel cell performance is to accelerate charge transfer kinetics, thereby enabling proton-conducting solid oxide fuel cells (H-SOFCs) to operate at higher performance levels than cells employing BaTb 0.8 Co 0.2 O 3 or BaCoO 3 cathodes alone. Furthermore, the favorable chemical stability of the BaTb 0.8 Co 0.2 O 3 +BaCoO 3 nanocomposite is maintained, thereby enhancing the fuel cell's operational stability. This research suggests that unanticipated phase segregation may occasionally improve the performance of the cathode, thereby presenting an interesting approach to cathode design in H-SOFCs. [ABSTRACT FROM AUTHOR]

Different transition metals are employed to tune the Y-doped BaZrO 3 proton conductor, resulting in the new BaZr 0.125 Y 0.125 M 0.75 O 3 (M = Cu, Mn, Ni, Zn, Co, and Fe) compositions as cathodes for proton-conducting solid oxide fuel cells. Only Co and Fe dopants can yield pure phases, whereas the use of other dopants results in impurities. Further experimental studies and first-principles calculations show that using Fe dopant has some advantages over Co-doped material, such as increased oxygen vacancies, lower proton migration energy barriers, and faster proton and oxygen diffusion kinetics. The fuel cell employing the BaZr 0.125 Y 0.125 Fe 0.75 O 3 (BZYFe) cathode has a larger fuel cell output than the fuel cell using the BaZr 0.125 Y 0.125 Co 0.75 O 3 (BZYCo) cathode. Furthermore, the CO 2 adsorption energy on the BZYFe surface is larger than that at the BZYCo surface, indicating that BZYFe has significantly better chemical stability than BZYCo. The long-term stability of the fuel cell demonstrates that the fuel cell with the BZYCo cathode is degrading. In contrast, the BZYFe cell has good operating stability. Given its phase purity, fuel cell performance, and stability, the Fe element is an appropriate dopant for altering BZY and creating a new cathode. • BaZr 0.125 Y 0.125 M 0.75 O 3 (M = Cu, Mn, Ni, Zn, Co, and Fe) were prepared. • Only Co and Fe dopants can generate pure phases. • BaZr 0.125 Y 0.125 Co 0.75 O 3 and BaZr 0.125 Y 0.125 Fe 0.75 O 3 cathodes yielded similar cell performance. • The cell using BaZr 0.125 Y 0.125 Fe 0.75 O 3 cathode showed better operational stability. [ABSTRACT FROM AUTHOR]

Novel magneto‐optical (MO) properties can be actualized through well‐designed nanostructures, greatly improving the application value of MO effects. As only p‐polarized light can generate transverse magneto‐optical Kerr effect (TMOKE) in traditional MO materials, it is quite challenging and valuable to effectuate TMOKE under s‐polarization incidence at optical frequencies. The constructed nanopillar structures in this work can realize a clear TMOKE under both s‐polarization and p‐polarization incidences, as proved by experiments and simulations. Under s‐polarized incident light with an elevation angle of 45°, electric dipole resonance (EDR) and electric quadrupole resonance (EQR) are excited, resulting in the significant enhancement of TMOKE (five orders of magnitude higher than for the planar Co film). The intensity of s‐polarized TMOKE shows an increase with the enhancing diameter and height of the nanopillar structure. The amplitude of p‐polarized TMOKE is also appreciably increased due to the excitation of surface plasmon polaritons (SPPs) and localized surface plasmons (LSPs). Moreover, the Fe and Ni nanopillars display similar reflectivity and s‐polarized TMOKE behaviors in simulations. The s‐polarized TMOKE is unexpectedly observed in ferromagnetic metals for the first time, which builds up a considerable platform for the development and application of novel MO phenomena. [ABSTRACT FROM AUTHOR]

AbstractMolecular information can be acquired from sample surfaces in real time using a revolutionary molecular imaging technique called mass spectrometry imaging (MSI). The technique can concurrently provide high spatial resolution information on the spatial distribution and relative proportion of many different compounds. Thus, many scientists have been drawn to the innovative capabilities of the MSI approach, leading to significant focus in various fields during the past few decades. This review describes the sampling protocol, working principle and applications of a few non-ambient and ambient ionization mass spectrometry imaging techniques. The non-ambient techniques include secondary ionization mass spectrometry and matrix-assisted laser desorption ionization, while the ambient techniques include desorption electrospray ionization, laser ablation electrospray ionization, probe electro-spray ionization, desorption atmospheric pressure photo-ionization and femtosecond laser desorption ionization. The review additionally addresses the advantages and disadvantages of ambient and non-ambient MSI techniques in relation to their suitability, particularly for biological samples used in tissue diagnostics. Last but not least, suggestions and conclusions are made regarding the challenges and future prospects of MSI. [ABSTRACT FROM AUTHOR]

It has been a big challenge to distinguish synchronous multiple primary lung cancer (sMPLC) from primary lung cancer with intrapulmonary metastases (IPM). We aimed to assess the clinical application of dynamic 18F-FDG PET/CT in patients with multiple lung cancer nodules. We enrolled patients with multiple pulmonary nodules who had undergone dynamic 18F-FDG PET/CT and divided them into sMPLC and IPM groups based on comprehensive features. The SUVmax, fitted K i value based on dynamic scanning, and corresponding maximum diameter ( D max ) from the two largest tumors were determined in each patient. We determined the absolute between-tumor difference of SU V max / D max and K i / D max (Δ SU V max / D max ; Δ K i / D max ) and assessed the between-group differences. Further, the diagnostic accuracy was evaluated by ROC analysis and the correlation between Δ SU V max / D max and Δ K i / D max from all groups was determined. There was no significant difference for Δ SU V max / D max between the IPM and sMPLC groups, while the IPM group had a significantly higher Δ K i / D max than the sMPLC group. The AUC of Δ K i / D max for differentiating sMPLC from IPM was 0.80 (cut-off value of K i = 0.0059 , sensitivity 79%, specificity 75%, p < 0.001). There was a good correlation (Pearson r = 0.91 , 95% CI: 0.79-0.96, p < 0.0001) between Δ SU V max / D max and Δ K i / D max in the IPM group but not in the sMPLC group (Pearson r = 0.45 , p > 0.05). Dynamic 18F-FDG PET/CT could be a useful tool for distinguishing sMPLC from IPM. K i calculation based on Patlak graphic analysis could be more sensitive than SUVmax in discriminating IPM from sMPLC in patients with multiple lung cancer nodules. [ABSTRACT FROM AUTHOR]

Pr 1.85 M 0.15 NiO 4+x (M represents Ba, Sr, or Ca) materials were prepared and evaluated as cathodes for protonic ceramic fuel cells (PCFCs). Compared with the Sr and Ba doping methods, the Ca-doping approach slightly enhanced the generation of interstitial oxygen and the surface catalytic activity in Pr 2 NiO 4. Furthermore, Ca-doping decreases the distance between O atoms in the lattice compared with the Sr and Ba-doped Pr 2 NiO 4 , facilitating the movement of charge carriers. Consequently, PCFCs employing Ca-doped Pr 2 NiO 4 cathodes achieve a much greater power density of 1279 mW cm−2 at 700 °C compared to fuel cells employing Sr-doped or Ba-doped Pr 2 NiO 4 cathodes. Furthermore, a PCFC employing a Ca-doped Pr 2 NiO 4 cathode exhibited excellent long-term stability under working conditions and operated continuously for over 280 h without any discernible deterioration. These results indicate that the Ca-doped Pr 2 NiO 4 cathode is a stable and effective candidate for PCFCs. [ABSTRACT FROM AUTHOR]

As a benchmark triple‐conducting cathode, BaCo0.4Fe0.4Zr0.1Y0.1O3−δ (BCFZY) has been widely investigated for protonic ceramic fuel cells (PCFC) in recent years. However, the reported electrochemical performance of BCFZY cathode differs, which is determined in this work to originate from the thermal expansion mismatch between BCFZY and electrolyte. Accordingly, two strategies for enhanced thermo‐mechanical compatibility are examined: impregnation and thermal expansion offset. In contrast to the impregnation of BCFZY nanoparticles on electrolyte backbones that only helps improve electrochemical performance, negative thermal expansion oxide Sm0.85Cu0.15MnO3−δ (SCM)‐offset BCFZY exhibits superior durability and activity simultaneously. Specifically, the polarization resistance decay rate of the SCM‐offset BCFZY is only ~0.2%/100 h, compared with ~18.75%/100 h for "impregnated BCFZY." Moreover, pure SCM generates moderate cathodic performance (area‐specific resistance = 0.11 Ω cm2, 700 °C), X‐ray diffraction and transmission electron microscopy reveal an in‐situ formed intergranular Ba2Cu3SmO7−δ phase at the boundaries of BCFZY and SCM. Thus, SCM can serve as a "three‐effect" additive, i) offset thermo‐expansion, ii) strengthen electrode structure and adhesion, and iii) provide acceptable oxygen‐reduction‐reaction activity, being favorable for superior performance. A PCFC using a SCM‐offset BCFZY cathode achieves the highest power density (1455 mW cm−2) yet recorded for PCFCs with BCFZY‐based cathodes. [ABSTRACT FROM AUTHOR]

Abstract: Sludge washout is listed among the top practical problems of the high rate upflow anaerobic reactors. This study investigated quantitatively two sludge washout processes operated under different hydrodynamic shear increase modes with the intervals of 1 and 10 days respectively. The results reveal that the sludge washout accompanying with large-scale granule disruption could lead to performance failure with heavy sludge loss ratio of about 46.1% at sludge loss rate about 0.35 gVSS L−1 d−1 during the process with shear increase interval of 1 day, while the highest sludge loss rate was only 0.12 gVSS L−1 d−1 during the process with 10-day interval. The intensified shear conditions could weaken the granules through inhibiting the extracellular polymers production and bioactivity. As consequences, an outbreak of large-scale granule disruption would raise and then significantly accelerate the sludge washout. Since long interval could provide the granules the opportunity to recover from these negative effects to some extent, the shear increase strategy of long interval over 10 days is favorably recommended to operate full-scale reactors during the start-up and shock load periods. The pioneer use of the micro particle image velocimetry in this study offers the possibility to discover the real hydrodynamic conditions around granules at microscale for the first time and reveals that the shear force exerts directly on the granular surface as a mechanical disruption force and big granules undergo high disruption force. The granule disruption is a result of the competition between the granule and the ambient hydrodynamic shear conditions rather than a process with shear force as a sole dominant factor. These could facilitate the understanding of the complicated interactions between the hydrodynamics and reactor performance and favor then a better control of the full-scale reactors. [Copyright &y& Elsevier]

Abstract: Ba0.5Sr0.5(Co0.8Fe0.2)1−xTixO3− δ (x=0, 0.05, and 0.1) materials were successfully prepared via an improved solid-state reaction route in an attempt to get better chemical stability for Ba0.5Sr0.5Co0.8Fe0.2O3− δ (BSCF). Stability tests showed that the novel Ti-doping strategy can effectively increase the chemical stability for Ba0.5Sr0.5Co0.8Fe0.2O3− δ in CO2-containing environments. The larger the Ti doping amount, the better the chemical stability. Ti-doped samples showed only a slight increase in area specific resistance (ASR) values, as shown from electrochemical tests performed on symmetrical cells. Therefore, anode-supported single fuel cells using BaZr0.4Ce0.4Y0.2O3− δ (BZCY) as the electrolyte and BZCY-Ba0.5Sr0.5(Co0.8Fe0.2)0.9Ti0.1O3− δ as the composite cathode, were fabricated and tested. The measured maximum power density values were 181, 116, and 49mWcm−2 at 700, 600, and 500°C, respectively. [Copyright &y& Elsevier]

Abstract: A BaZr0.4Ce0.4Y0.2O3− δ (BZCY)-NiO anode functional layer was added between the BZCY electrolyte and the BZCY-NiO anode substrate to investigate its effect on the performance of single cells. With BaZr0.4Ce0.4Y0.2O3− δ (BZCY) as the electrolyte and composite BZCY-Ba0.5Sr0.5(Co0.8Fe0.2)0.9Ti0.1O3− δ as the cathode material, anode-supported electrolyte fuel cells were fabricated and tested. The single cell without an anode functional layer generated maximum power densities of 181, 138, 116, 77, and 49mWcm−2 at 700, 650, 600, 550, and 500°C, respectively, whereas those for the single cell with an anode functional layer significantly improved up to 281, 243, 194, 145, and 95mWcm−2 at the same temperatures, almost doubling the power output. Electrochemical impedance spectroscopy (EIS) measurements for these two cells revealed that the addition of the anode functional layer reduced the contact resistance as well as the polarization resistance for the cell, resulting thus in the improved cell performance. [Copyright &y& Elsevier]

Non-reciprocal photonic devices, including optical isolators and circulators, are indispensible components in optical communication systems. However, the integration of such devices on semiconductor platforms has been challenging because of material incompatibilities between semiconductors and magneto-optical materials that necessitate wafer bonding, and because of the large footprint of isolator designs. Here, we report the first monolithically integrated magneto-optical isolator on silicon. Using a non-reciprocal optical resonator on an silicon-on-insulator substrate, we demonstrate unidirectional optical transmission with an isolation ratio up to 19.5 dB near the 1,550 nm telecommunication wavelength in a homogeneous external magnetic field. Our device has a small footprint that is 290 µm in length, significantly smaller than a conventional integrated optical isolator on a single crystal garnet substrate. This monolithically integrated non-reciprocal optical resonator may serve as a fundamental building block in a variety of ultracompact silicon photonic devices including optical isolators and circulators, enabling future low-cost, large-scale integration. [ABSTRACT FROM AUTHOR]

Abstract: In3+ was used as dopant for BaZrO3 proton conductor and 30 at%-doped BaZrO3 samples (BaZr0.7In0.3O3-δ , BZI) were prepared as electrolyte materials for proton-conducting solid oxide fuel cells (SOFCs). The BZI material showed a much improved sinteractivity compared with the conventional Y-doped BaZrO3. The BZI pellets reached almost full density after sintering at 1600°C for 10h, whereas the Y-doped BaZrO3 samples still remained porous under the same sintering conditions. The conductivity measurements indicated that BZI pellets showed smaller bulk but improved grain boundary proton conductivity, when compared with Y-doped BaZrO3 samples. A total proton conductivity of 1.7×10−3 Scm−1 was obtained for the BZI sample at 700°C in wet 10% H2 atmosphere. The BZI electrolyte material also showed adequate chemical stability against CO2 and H2O, which is promising for application in fuel cells. [Copyright &y& Elsevier]

Abstract: The La1.95Ca0.05Ce2O7−δ (LCCO) material is successfully synthesized using the Pechini method. The synthesized powders are exposed to atmospheric CO2 and H2 with 3% H2O at 700°C. The treated LCCO powders are investigated using X-ray diffraction (XRD) to study the chemical stability. According to the XRD results, LCCO is very stable and shows no reactions with CO2 or H2O. A fuel cell with the LCCO electrolyte is prepared using the suspension spray method and is tested in the range from 600°C to 700°C using humidified hydrogen (∼3% H2O) as the fuel and static air as the oxidant. An open-circuit potential of 0.832V and a maximum power density of 259mWcm−2 are obtained for a single cell with an interface resistance of 0.23Ωcm2 at 700°C. [Copyright &y& Elsevier]

Abstract: A new physical-geometric optics hybrid (PGOH) method is developed to compute the scattering and absorption properties of ice particles. This method is suitable for studying the optical properties of ice particles with arbitrary orientations, complex refractive indices (i.e., particles with significant absorption), and size parameters (proportional to the ratio of particle size to incident wavelength) larger than ∼20, and includes consideration of the edge effects necessary for accurate determination of the extinction and absorption efficiencies. Light beams with polygon-shaped cross sections propagate within a particle and are traced by using a beam-splitting technique. The electric field associated with a beam is calculated using a beam-tracing process in which the amplitude and phase variations over the wavefront of the localized wave associated with the beam are considered analytically. The geometric-optics near field for each ray is obtained, and the single-scattering properties of particles are calculated from electromagnetic integral equations. The present method does not assume additional physical simplifications and approximations, except for geometric optics principles, and may be regarded as a “benchmark” within the framework of the geometric optics approach. The computational time is on the order of seconds for a single-orientation simulation and is essentially independent of the size parameter. The single-scattering properties of oriented hexagonal ice particles (ice plates and hexagons) are presented. The numerical results are compared with those computed from the discrete-dipole-approximation (DDA) method. [Copyright &y& Elsevier]

Abstract: The scattering of light by dielectric particles much larger than the wavelength of incident light is attributed to diffraction, external reflection and outgoing refracted waves. This paper focuses on diffraction and external reflection by faceted particles, which can be calculated semi-analytically based on physical optics. Three approximate methods; the surface-integral method (SIM), the volume-integral method (VIM), and the diffraction plus reflection pattern from ray optics (DPR) are compared. Four elements of the amplitude scattering matrix in the SIM and the VIM are presented in an explicit form. Of interest is that diffraction and external reflection are separable in the SIM, whereas they are combined in the VIM. A feature of zero forward reflection is noticed in the SIM. The applicability of the DPR method is restricted to particles with random orientations. In the manner of van de Hulst, we develop a new technique to compute the reflection pattern of randomly oriented convex particles using spheres with the same refractive index, resulting in an improvement in the precision of the reflection calculation in near-forward and near-backward directions. The accuracy of the aforementioned three methods is investigated by comparing their results with those from the discrete-dipole-approximation (DDA) method for hexagonal particles at the refractive index of 1.3+i1.0. For particles with fixed orientations, it is found that the SIM and the VIM are comparable in accuracy and applicable when the size parameter is on the order of 20. The ray-spreading effect on the phase function is evident from the results of various size parameters. For randomly oriented particles, the DPR is more efficient than the SIM and the VIM. [ABSTRACT FROM AUTHOR]

Abstract: The far field within the context of the Lorenz–Mie theory and the T-matrix formulation is usually expressed on the basis of the asymptotic properties of vector spherical waves. The radiation condition is taken into account by employing proper vector spherical functions as the expansion basis of the scattered field. The asymptotic behavior of the Hankel function is obtained from differential equations. The asymptotic far field can also be obtained from the Kirchhoff surface integral equation, in which the radiation condition has been implemented when it is derived from the Maxwell equations. This note is to present an explicit establishment of the relationship between the asymptotic far field and the near field in the Lorenz–Mie theory and the T-matrix formulation through the Kirchhoff surface integral. [Copyright &y& Elsevier]

Abstract: A series of cobalt-free and low cost BaCe x Fe1−x O3−δ (x =0.15, 0.50, 0.85) materials are successful synthesized and used as the cathode materials for proton-conducting solid oxide fuel cells (SOFCs). The single cell, consisting of a BaZr0.1Ce0.7Y0.2O3−δ (BZCY7)-NiO anode substrate, a BZCY7 anode functional layer, a BZCY7 electrolyte membrane and a BaCe x Fe1−x O3−δ cathode layer, is assembled and tested from 600 to 700°C with humidified hydrogen (∼3% H2O) as the fuel and the static air as the oxidant. Within all the cathode materials above, the cathode BaCe0.5Fe0.5O3−δ shows the highest cell performance which could obtain an open-circuit potential of 0.99V and a maximum power density of 395mWcm−2 at 700°C. The results indicate that the Fe-doped barium cerates can be promising cathodes for proton-conducting SOFCs. [Copyright &y& Elsevier]

Abstract: La0.3Sr0.7FeO3-δ (LSF)/CeO2 cathode supported Ce0.8Sm0.2O2-δ (SDC) electrolyte was prepared by a simple multilayer tape casting and co-firing method. SDC electrolyte slurry and LSF/CeO2 cathode slurry were optimized and the green bi-layer tapes were co-fired at different temperature. Phase characterizations and microstructures of electrolyte and cathode were studied by X-ray diffraction (XRD) and Scan Electronic Microscopy (SEM). No additional phase peak line was observed in electrolyte and cathode support when the sintering temperature lower was than 1400°C. The electrolytes were extremely dense with the thickness of about 20μm. The cathode support was porous with electrical conductivity of about 4.21S/cm at 750°C. With Ni/SDC as anode, Open Current Voltage and maximum power density reached 0.61V and 233mWcm−2 at 750°C, respectively. [Copyright &y& Elsevier]

Abstract: We describe a solid state reaction for the preparation of both NiO–BaCe0.7Ta0.1Y0.2O3−δ anode substrates and BaCe0.7Ta0.1Y0.2O3−δ (BCTY10) electrolyte membranes on porous NiO–BCTY10 anode substrates. The amounts of the pore forming additive in the substrates showed a significant influence on the densification of the BCTY10 membranes. After sintering at 1450°C for 5h, the BCTY10 membrane on a NiO–BCTY10 anode containing 30wt.% starch achieved a high density and showed adequate chemical stability against H2O and CO2. The chemical stability of BCTY10 was even better than that of BaCe0.7Zr0.1Y0.2O3−δ . With a mixture of BaCe0.7Zr0.1Y0.2O3−δ (BZCY7) and La0.7Sr0.3FeO3−δ (LSF) as a cathode, a single fuel cell with 12μm thick BCTY10 electrolyte generated maximum power densities of 142, 93, 29mW/cm2 at 700, 600 and 500°C, respectively. The electrolyte resistance and interfacial polarization resistance of the cell under open circuit conditions were also investigated. [Copyright &y& Elsevier]

Abstract: Proton-conducting BaCeO3 membranes with different In-doping levels (from 10 to 30%) were fabricated on NiO-based anode substrates. Indium, which was only used as a trivalent element to create oxygen vacancies in BaCeO3 previously, was found to have the function of stabilizing BaCeO3 in this study. The In-doped BaCeO3 showed improved chemical stability against CO2, while even the traditional BaCeO3 substituting with a small amount of Zr decomposed in the same environment. Furthermore, unlike other strategies for stabilizing BaCeO3, the supported In-doped BaCeO3 membrane became dense after firing at relatively low temperatures. We also investigated the influences of the sintering temperatures and the In-doping levels on the densification and the electrical properties of the supported BaCeO3 membranes, which revealed that the In-doping strategy increased both the chemical stability and sinterability for BaCeO3 with little loss of electrical performance. [Copyright &y& Elsevier]

Abstract: Proton-conducting solid oxide fuel cells (SOFCs), consisting of BaCe0.7In0.3O3−δ (BCI30)-NiO anode substrates, BCI30 anode functional layers, BCI30 electrolyte membranes and BCI30-LaSr3Co1.5Fe1.5O10−δ (LSCF) composite cathode layers, were successfully fabricated at 1150°C, 1250°C and 1350°C respectively by a single step co-firing process. The fuel cells were tested with humidified hydrogen (∼3%H2O) as the fuel and static air as the oxidant. The single cell co-fired at 1250°C showed the highest cell performance. The impedance studies revealed that the co-firing temperature affected the interfacial polarization resistance of a single cell as well as its overall electrolyte resistance. [Copyright &y& Elsevier]

Abstract: Hydrogen permeation flux of Ni–BaZr0.1Ce0.7Y0.2O3– δ cermet (ceramic–metal composite) was measured in an H2S-containing atmosphere at 973K. In 30 and 60ppm H2S, the hydrogen permeation flux decreased by about 20% and 30%, respectively. After the removal of H2S, the hydrogen permeation flux recovered partially in several hours and then remained stable. After exposing to 60ppm H2S, X-ray diffraction (XRD) analysis revealed a little formation of Ni3S2, BaS, and doped CeO2. Thermodynamic calculation results showed that the critical value of pH2S/pH2 for the formation of Ni3S2 was about 0.0066 at 973K, suggesting that the Ni3S2 found after testing was formed in the cooling process. The reaction between H2S and BaCeO3 was rather weak and could not be the cause of the performance loss. Analysis of poisoning and regeneration behavior suggested that the adsorption of sulfur on nickel surface caused the performance loss. [Copyright &y& Elsevier]

Abstract: Screen-printing technology was employed to fabricate BaCe0.8Sm0.2O3−δ (BCS) electrolyte membranes on porous NiO–BCS anode substrates. With a mixture of BCS and La0.7Sr0.3FeO3−σ as cathode, a single cell with 16μm thick BCS electrolyte generated maximum power densities of 222, 141, 72mW/cm2 at 700, 650 and 600°C, respectively. After the electrolyte surface was modified by spray coating, the single cell with 16μm thick BCS electrolyte generated maximum power densities of 352, 241, 125mW/cm2 at 700, 650 and 600°C, respectively. The improved performance of the fuel cell was attributed to the surface modification by spray coating promoting the adherence of the cathode to electrolyte, which was confirmed by both scanning electron microscope (SEM) observation and impedance measurement. The results illustrate that screen-printing technology with spray coating is a simple and low cost method for preparing thin electrolyte membranes of protonic ceramic fuel cells. [Copyright &y& Elsevier]

Abstract: Stable BaCe0.5Zr0.3Y0.16Zn0.04O3−δ (BCZYZ) thin membrane was successfully prepared by in situ tape casting/co-firing method for proton-conducting solid oxide fuel cells. The starting powders were BaCO3, CeO2, ZrO2, Y2O3, ZnO for electrolyte and BaCO3, CeO2, ZrO2, Y2O3, ZnO, NiO, graphite for anode. The anode/electrolyte bi-layers were prepared by a simple multi-layer tape casting/co-firing method. The phase characterizations and microstructures were studied by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The anode–electrolyte bi-layers were sintered at 1450°C. The electrolytes were extremely dense with pure perovskite phase and the thickness was about 25μm. The anodes were porous and no obvious reaction was found between NiO and BCZYZ. With LaSr3Co1.5Fe1.5O10−δ (LSCF)/BCZYZ as cathode, the open current voltage and maximum power density respectively, reached 1.00V and 247mWcm−2 at 650°C. [Copyright &y& Elsevier]

Abstract: A high In-dopant level BaCeO3 material was used as an electrolyte for a proton-conducting solid oxide fuel cell (SOFC). Indium behaved as an ideal dopant for BaCeO3, which improved both the chemical stability and sinterability for BaCeO3 greatly. The anode supported BaCe0.7In0.3O3−δ (BCI30) membrane reached dense after sintering at 1100°C, much lower than the sintering temperature for other BaCeO3-based materials. Additionally, the BCI30 membrane showed adequate chemical stability against CO2 compared with the traditional rare earth doped BaCeO3. The BCI30-based fuel cell also showed a reasonable cell performance and a good long-term stability under the operating condition. Besides, the LaSr3Co1.5Fe1.5O10−δ (LSCF) was also evaluated as a potential cathode candidate for a proton-conducting SOFC. [Copyright &y& Elsevier]

A thin Ba3Ca1.18Nb1.82O9−δ (BCN18) membrane electrolyte was prepared by a novel and facile method on a NiO–BCN18 anode substrate. The interesting aspect of the method was the adoption of a in situ reaction of BaCO3, CaCO3, and Nb2O5 on the anode substrate to prepare a dense BCN18 membrane. The BCN18 membrane obtained, which was about 15 μm in thickness and showed high chemical stability against H2O and CO2, attained a high density after sintering at 1400°C. The elemental composition of the BCN18 membrane prepared was identified by energy-dispersive X-ray spectroscopy analysis. With La0.7Sr0.3FeO3−σ (LSF) as the cathode, the fuel cell performance with the structure of Ni–BCN18/BCN18/LSF was studied. [ABSTRACT FROM AUTHOR]

Detection of explosives at trace levels is crucial for security purposes because of increasing worldwide terrorist threats at public places. Previously, a hollow cathode discharge (HCD) ion source has been fabricated for detection of explosives. Recently, the HCD ion source has been modified for a dual pressures operating system and coupled to a linear ion trap MS to analyze explosives simultaneously. Here, trinitrotoluene (TNT), nitroglycerin (NG), pentaerythritol tetranitrate (PETN) and 1,3,5-trinitroperhydro-1,3,5-triazine (RDX) were taken as model explosive compounds and the mass spectra were recorded in the negative mode ionization. At the higher ion source pressure (~28.0–30.0 Torr), NG, PETN and RDX gave adduct ions with the NO 3 − ion while TNT showed the [TNT + NO 3 –HNO 2 ]- (m/z 242) simultaneously. However, NG and PETN did not give any ion signals at the lower ion source pressure (~0.8–1.0 Torr) while TNT exhibited its molecular ion, [TNT]-• (m/z 227), as a major ion through electron attachment and RDX showed fragment ions that followed electron capture dissociation concurrently. The modified HCD ion source exhibited better sensitivity in simultaneous detection and quantification of the explosives. The NO 3 − and NO 2 − as reagent ions in the air HCD plasma form stable adduct ions with the NG, PETN and RDX even with TNT at the higher temperature (140–200 °C). The formation of the NO 3 −, NO 2 − in the HCD plasma also causes the formation of [TNT-H]- (m/z 226) at the higher ion source pressure. The inner metallic surface of the hollow tube assists the Birch reduction type reaction that results in the formation of hydride ion of the TNT, [TNT + H]- (m/z 228). No significant difference in the spectral pattern for simultaneous and individual measurements for the explosives was observed at the higher ion source pressure. Therefore, it may conclude that the present modified HCD ion source can be used for simultaneous detection and quantification of the explosive compounds at trace and/or ultra-trace levels using air as a carrier gas. Simultaneous detection and quantification of explosives by a modified hollow cathode discharge ion source. [Display omitted] • Fabrication of dual pressures hollow cathode discharge ion source. • Simultaneous detection and quantification of explosive compounds. • Adduct ions of NG, TNT, PETN and RDX with NO 3 − at high ion source pressure. • Electron attachment reaction predominates at low ion source pressure. • Birch reduction type reaction causes formation of hydride ion of TNT, [TNT + H]-. [ABSTRACT FROM AUTHOR]

Abstract: A novel composition of BaCe0.7Ta0.1Y0.2O3− δ (BCTY10) electrolyte membrane was successfully fabricated on porous NiO-BCTY10 anode substrate. The anode was prepared through a route combining a solid state reaction and a wet chemical method. After sintering at 1450°C for 5h, the BCTY10 membrane showed adequate chemical stability against CO2 and H2O. With a mixture of La0.7Sr0.3FeO3− δ (LSF) and BaCe0.7Zr0.1Y0.2O3− δ (BZCY7) as cathode, a single fuel cell with 25μm thick BCTY10 electrolyte generated maximum power densities of 195, 137, 84, 44mW/cm2 at 700, 650, 600 and 550°C, respectively. The interface resistance of the cell under open circuit condition was also investigated. [Copyright &y& Elsevier]

Abstract: Composite membranes based on Ni and Zr-doped BaCeO3 are promising for hydrogen separation. Such composites show high proton conductivity and adequate chemical stability in H2O and CO2, but may be unstable in H2S. In this work, the hydrogen permeation performance of Ni–BaZr0.1Ce0.7Y0.2O3−δ was measured in an H2S-containing atmosphere at 900°C. The hydrogen permeation flux began to degrade in 60ppm H2S and decreased by about 45% in 300ppm H2S. After hydrogen permeation tests, X-ray diffraction analysis revealed the formation of BaS, doped CeO2, Ni3S2 and Ce2O2S. Analysis of the microstructure and phase composition, and results of thermodynamic calculations suggest that reaction between H2S and doped BaCeO3 caused the performance loss of the Ni–BaZr0.1Ce0.7Y0.2O3−δ . [Copyright &y& Elsevier]

Abstract Mass spectrometry (MS) is a formidable analytical tool for the analysis of non-polar to polar compounds individually and/or from mixtures, providing information on the molecular weights and chemical structures of the analytes. During the last more than one-decade, ambient ionization mass spectrometry (AIMS) has developed quickly, producing a wide range of platforms and proving scientific improvements in a variety of domains, from biological imaging to quick quality control. These methods have made it possible to detect target analytes in real time without sample preparation in an open environment, and they can be connected to any MS system with an atmospheric pressure interface. They also have the ability to analyze explosives, illicit drugs, disease diagnostics, drugs in biological samples, adulterants in food and agricultural products, reaction progress, and environmental monitoring. The development of novel ambient ionization techniques, such as probe electrospray ionization, paper spray ionization, and fiber spray ionization, employed even at picolitre to femtolitre solution levels to provide femtogram to attogram levels of the target analytes. The special characteristic of this ambient ion source, which has been extensively used, is the noninvasive property of PESI of examination of biological real samples. The results in the current review supports the idea that AIMS has emerged as a pioneer in MS-based approaches and that methods will continue to be developed along with improvements to existing ones in the near future. [ABSTRACT FROM AUTHOR]

• We propose a spatial-sequential CNN network for temporal left ventricle segmentation on 4D cardiac sequence. • We utilize the sequential consistency (cardiac motion) to improve the LV segmentation during cardiac systole. • We present an unsupervised sequential CNN network to capture cardiac motion in heart cycle. • We introduce a bi-directional learning strategy to further refine the results. • We achieve higher accuracy compared to the state-of-the-art methods on 4D cardiac CT dataset. Automated segmentation of left ventricular cavity (LVC) in temporal cardiac image sequences (consisting of multiple time-points) is a fundamental requirement for quantitative analysis of cardiac structural and functional changes. Deep learning methods for segmentation are the state-of-the-art in performance; however, these methods are generally formulated to work on a single time-point, and thus disregard the complementary information available from the temporal image sequences that can aid in segmentation accuracy and consistency across the time-points. In particular, single time-point segmentation methods perform poorly in segmenting the end-systole (ES) phase image in the cardiac sequence, where the left ventricle deforms to the smallest irregular shape, and the boundary between the blood chamber and the myocardium becomes inconspicuous and ambiguous. To overcome these limitations in automatically segmenting temporal LVCs, we present a spatial sequential network (SS-Net) to learn the deformation and motion characteristics of the LVCs in an unsupervised manner; these characteristics are then integrated with sequential context information derived from bi-directional learning (BL) where both chronological and reverse-chronological directions of the image sequence are used. Our experimental results on a cardiac computed tomography (CT) dataset demonstrate that our spatial-sequential network with bi-directional learning (SS-BL-Net) outperforms existing methods for spatiotemporal LVC segmentation. [ABSTRACT FROM AUTHOR]

Electromagnetic wave scattering by ice particles is commonly modeled by defining representative habits, including droxtals, columns, plates, and aggregates, although actual particles in the atmosphere can be even much more complex. In this study, we examined a superspheroidal approximation method for modeling electromagnetic wave scattering by ice crystals. Superspheroid can be associated with a shape index (SI) defined by the particle volume and average projected area. Corresponding to realistic ice crystals, suitable superspheroid models with the same SI (that means, identical volume and average projected area) and aspect ratio can be identified as surrogates for optical property calculations. We systematically compared the optical properties of ice crystals and superspheroids at 33 microwave bands in the range of 3–640 GHz and at three representative visible or infrared wavelengths (0.66, 2.13, and 11 μm). It was found that the single-scattering properties of compact ice crystal habits and their superspheroidal model particles were quite close. For an aggregate with sparse distribution of elements, a superspheroid model produces relatively large errors because the aspect ratio may not be sufficient to describe a particle shape. However, the optical similarity of a superspheroid and an aggregate is still encouraging. [ABSTRACT FROM AUTHOR]

• A new multi-modality tumour segmentation method for positron emission tomography – computed tomography (pet-ct) images. • A recurrent fusion network to fuse multi-modality image features in various forms. • An interconnect link module to iteratively propagate multi-modality image features across multiple correlated image feature scales. • Integrating intermediary segmentation results and multi-modality image features to progressively refine the segmentation results. • Achieved consistent segmentation results with different network architectures across different datasets. Background and objective: [18f]-fluorodeoxyglucose (fdg) positron emission tomography – computed tomography (pet-ct) is now the preferred imaging modality for staging many cancers. Pet images characterize tumoral glucose metabolism while ct depicts the complementary anatomical localization of the tumor. Automatic tumor segmentation is an important step in image analysis in computer aided diagnosis systems. Recently, fully convolutional networks (fcns), with their ability to leverage annotated datasets and extract image feature representations, have become the state-of-the-art in tumor segmentation. There are limited fcn based methods that support multi-modality images and current methods have primarily focused on the fusion of multi-modality image features at various stages, i.e., early-fusion where the multi-modality image features are fused prior to fcn, late-fusion with the resultant features fused and hyper-fusion where multi-modality image features are fused across multiple image feature scales. Early- and late-fusion methods, however, have inherent, limited freedom to fuse complementary multi-modality image features. The hyper-fusion methods learn different image features across different image feature scales that can result in inaccurate segmentations, in particular, in situations where the tumors have heterogeneous textures. Methods: we propose a recurrent fusion network (rfn), which consists of multiple recurrent fusion phases to progressively fuse the complementary multi-modality image features with intermediary segmentation results derived at individual recurrent fusion phases: (1) the recurrent fusion phases iteratively learn the image features and then refine the subsequent segmentation results; and, (2) the intermediary segmentation results allows our method to focus on learning the multi-modality image features around these intermediary segmentation results, which minimize the risk of inconsistent feature learning. Results: we evaluated our method on two pathologically proven non-small cell lung cancer pet-ct datasets. We compared our method to the commonly used fusion methods (early-fusion, late-fusion and hyper-fusion) and the state-of-the-art pet-ct tumor segmentation methods on various network backbones (resnet, densenet and 3d-unet). Our results show that the rfn provides more accurate segmentation compared to the existing methods and is generalizable to different datasets. Conclusions: we show that learning through multiple recurrent fusion phases allows the iterative re-use of multi-modality image features that refines tumor segmentation results. We also identify that our rfn produces consistent segmentation results across different network architectures. [ABSTRACT FROM AUTHOR]

Uranium cations were immobilized in the proton-conducting oxide BaCe 0.8 Y 0.2 O 3 (BCY) by partially replacing Ce with U. Uranium cations can be incorporated into the BCY lattice to form the new BaCe 0.7 Y 0.2 U 0.1 O 3 (BCUY) compound. This new BCUY material shows an improved chemical stability against CO 2 compared with the traditional BCY material. The first-principles calculations reveal that the doping of U elevates the energy barrier for the interaction between BCUY and CO 2 , which is the reason for the improved chemical stability. Despite the improved chemical stability, U-doping inhibits the grain growth for the BaCeO 3 proton-conducting oxide, making the grain size of the sintered BCUY reach only 0.5 μm, which is approximately one-tenth of that for BCY sintered at the same temperature. As a result, the conductivity of BCUY is 2.8 × 10−3 S cm−1 at 700 °C. The H-SOFC using a BCUY electrolyte reaches a peak power density of 237 mW cm−2 at 700 °C, which is lower than that for BCY cells, but comparable to that using other proton-conducting electrolytes. The current study demonstrates that U cations can be immobilized in BCY proton-conducting oxide, and that U-doping improves the stability of the material at the cost of reducing the sinterability, and thus conductivity. [ABSTRACT FROM AUTHOR]

Phase change materials, such as vanadium dioxide (VO2) and Titanium dioxide (Ti2O3) have received extensive attention because of the dramatic changes in their intrinsic properties during phase transitions. However, due to the rapid transition rate and wide dynamics, monitoring of processes is challenging. Previous detection methods are lack of speed and simplicity and require multiple interventions, which largely introduce human factors influencing the results and make it difficult to guarantee the accuracy and visualization. In this paper, the photonic spin Hall effect is used for real-time detection and highly sensitive analysis of the phase transition process of VO2 films. By incorporating with quantum weak measurement, the photonic spin-Hall shift acts as the pointer, and the phase transition process of VO2 is characterized effectively. The high measurement resolution with 63 S/(m μm) is achieved due to weak-value amplification. In our scheme, it does not involve any mechanical adjustment of optical components, thus enabling real-time, visual, non-contact detection of dynamic phase transition processes. [ABSTRACT FROM AUTHOR]