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Abstract Background Nonlinear optical microscopic (NLOM) imaging technique shows its high resolution imaging features in histocytology. The purpose of this study was to investigate NLOM imaging technique as a useful tool for a donor kidney quality assessment. Materials and Methods Eighty-three pretransplant kidney biopsies from adult donors were analyzed retrospectively. Each specimen was paraffin-embedded and sectioned into 2 consecutive 5-μm thick sections. One section was stained with Masson trichrome, and the other was left unstained for NLOM imaging using second harmonic generation combined with two-photon excited fluorescence (SHG/TPEF). The pretransplant kidney quality was assessed by an experienced pathologist using the Remuzzi scoring system, which characterizes renal tissue morphology into 4 aspects: tubular atrophy, interstitial fibrosis, glomerulosclerosis, and vascular injury. The K coefficient was used to measure the consistency of the Remuzzi scores between conventional Masson trichrome stained images and SHG/TPEF images. Results NLOM imaging technology can capture high-resolution tissue images from unstained renal tissue, is easy to operate, and shortens time-consuming histological processing procedures. No significant differences (P >.05) were found between the Remuzzi scores of the SHG/TPEF images and the Masson trichrome stained images. The high κ coefficients (0.804–0.895) showed a good consistency between these 2 techniques. Conclusion The NLOM technique is suitable for renal tissue imaging and could potentially be used for routine pretransplant kidney evaluation in clinical settings. Highlights • NLOM imaging technique shows its high-resolution imaging features in histocytology. • The NLOM technique is suitable for renal tissue imaging. • The NLOM technique could be used for pretransplant kidney evaluation. [ABSTRACT FROM AUTHOR]

For a slope with a large number of potential slip surfaces, the consequence of slope failure along different slip surfaces could be quite different. When the soil parameters are uncertain, the location of the slip surface with minimum factor of safety is also uncertain, making the consequence of slope failure also uncertain. The traditional equation for risk assessment may only be suitable for slope failure along a given slip surface, but may not be directly applicable to slope failure with a large number of potential slip surfaces. In this study, a new equation is suggested for risk assessment of slope failure considering the system failure probability. A response surface method is used to enhance the computational efficiency. Three slopes are studied to illustrate the proposed method. It is found that the consequence of slope failure is an important weighting factor in the risk assessment of slope failure. A slip surface with a larger failure probability but small consequence may be associated with a smaller risk. Hence, the most probable failure surface may not always be the slip surface with the largest risk. For the three examples studied in this paper, the risk of slope failure are all governed by the representative slip surfaces. Therefore, the risk of slope failure can then be assessed in a simplified manner by taking into account only the representative slip surfaces. Both the reliability method and empirical method can be used for representative slip surfaces identification. [ABSTRACT FROM AUTHOR]

The atom distribution and electronic properties of (010), (001) and (100) planes of MnWO 4 and FeWO 4 were studied based on a DFT calculation. The surface stabilities of the three planes were compared according to their surface energies. The most stable one is (010) plane, followed by (001) and (100). (010) and (001) are the main planes for absorption of anion collector ions, which is supported by their bonding relationship and charge density distribution of surface atoms and finally proved by the results of flotation test and stereomicroscope analysis. In addition, the tungsten atoms can be viewed as the absorption site for collectors in (001) plane but not in (010) plane, which can explain the phenomenon in flotation test that the recovery of wolframite can hardly be further boosted even with a high dosage of BHA. [ABSTRACT FROM AUTHOR]

By means of surface mechanical rolling treatment (SMRT), a gradient nanostructured (GNS) surface layer was formed on AISI 316L stainless steel. The mean grain size is ∼30 nm in the topmost surface layer and increases with depth. Tension–compression fatigue measurements were performed on the SMRT sample under the stress-controlled mode. In comparison with the coarse-grained sample, the fatigue strength of the SMRT sample is significantly enhanced in both the low- and high- cycling fatigue regimes. Meanwhile, the fatigue ratio is evidently elevated with an increasing tensile strength in the SMRT sample. The initiation and growth of cracks, the cyclic deformation behaviors, as well as effects of strength and residual stresses, have been investigated to clarify the fatigue mechanism of the SMRT sample. The results emphasized the GNS surface layer enhances the fatigue property by suppressing the initiation of cracks and accommodating a remarkable cyclic plastic strain amplitude. [ABSTRACT FROM AUTHOR]

Highlights: [•] The Re1−xRu x B2 is more stable than that of Ru1−xRe x B2. [•] The Re0.5Ru0.5B2 is the most stable structure. [•] The elastic modulus of this binary alloy borides are related to Re concentration. [•] This binary alloy borides exhibit brittle behavior. [•] The B/G ratio of Re0.75Ru0.25B2 (1.23) is lower than that of ReB2 (1.29). [ABSTRACT FROM AUTHOR]

Highlights: [•] U-doped system with cubic structure is more stable than the monoclinic structure. [•] The elastic modulus of cubic structure is higher than the monoclinic structure. [•] U-doped weakens the resistance to shear deformation of ZrO2. [•] U-doped enhances the resistance to shape deformation for monoclinic structure. [ABSTRACT FROM AUTHOR]

Abstract: The aerobic degradation of 4,4′-Dibromodiphenyl ether (BDE-15) and the changes in the microbial community in river sediment from southern Taiwan were assessed in this study. The aerobic degradation of BDE-15 was enhanced by the addition of surfactin or rhamnolipid, and was inhibited by the addition of brij 30 or brij 35. The optimal conditions were stimulated by the addition of surfactin into the sediment. The degradation of BDE-15 was enhanced by a second and third addition of BDE-15 into the batch cultures. The addition of BDE-degrading bacteria could also enhance the efficiency of BDE-15 degradation in sediment. Pseudomonas sp. and Bacillus sp. were found to be the dominant bacteria in the process of BDE-15 degradation in the sediment. The addition of various treatments altered the microbial community composition in river sediment. These findings could provide useful information for bioremediation of DBE-15 contaminated sites. [Copyright &y& Elsevier]

Compared to experiment, the adsorption energies, bonding properties, and electronic structure of two different Al2O3/B4C bridge sites with seven different Al2O3 surfaces are investigated by ab initio periodic density functional theory. The Al2O3/B4C ceramic sintered in Ar is synthesized and measured by XRD and TEM. The calculated results reveal that the densification of O_bridge site of Al2O3/B4C surface is better than that of Al_bridge. The Al2O3 (113)/B4C with O_bridge is the most favorable and stable. The electronic structure shows that the electron hybridization exists between Al, O atoms and C, B atoms. The results indicate that the calculated results are in good agreement with the experiment. [ABSTRACT FROM AUTHOR]

Abstract: Al2O3–14wt%B4C composites with 0–1wt% C addition were sintered in Ar at 1550–1650°C. The influence of the C additive on the B loss, densification behavior, and microstructure of the Al2O3–B4C composites were investigated. The results show that there are B2O3, H3BO3 and Al18B4O33 exist between Al2O3 and B4C interface, which result in B loss because of B2O3''s high vapor tension at above 1500°C. The presence of Al18B4O33 grains formed by chemical reaction of Al2O3 with surface oxides on B4C inhibit the densification of pellets by reducing the specific free surface energy of the Al2O3. However, the added C eliminates those oxides to reduce B loss because of its higher activity than B4C, and it also coarsens Al2O3 grain although the density of pellets is decreased by gas products. [Copyright &y& Elsevier]

Abstract: GaN-based LEDs with photonic crystal (PhC) patterns on an n- and a p-GaN layer by nano-imprint lithography (NIL) are fabricated and investigated. At a driving current of 20mA on Transistor Outline (TO)-can package, the light output power of the GaN-based LED with PhC patterns on an n- and a p-GaN layer is enhanced by a factor of 1.30, and the wall-plug efficiency is increased by 24%. In addition, the higher output power of the LED with PhC patterns on the n- and p-GaN layer is due to better crystal quality on n-GaN and higher scattering effect on p-GaN surface using PhC pattern structure. [ABSTRACT FROM AUTHOR]

Abstract: The non-Gaussian Karhunen–Loeve (K–L) expansion is very attractive because it can be extended readily to non-stationary and multi-dimensional fields in a unified way. However, for strongly non-Gaussian processes, the original procedure is unable to match the distribution tails well. This paper proposes an effective solution to this tail mismatch problem using a modified orthogonalization technique that reduces the degree of shuffling within columns containing empirical realizations of the K–L random variables. Numerical examples demonstrate that the present algorithm is capable of matching highly non-Gaussian marginal distributions and stationary/non-stationary covariance functions simultaneously to a very accurate degree. The ability to converge correctly to an abrupt lower bound in the target marginal distributions studied is noteworthy. [Copyright &y& Elsevier]

The series representation consisting of eigenfunctions as the orthogonal basis is called the Karhunen–Loeve expansion. This paper demonstrates that the determination of eigensolutions using a wavelet-Galerkin scheme for Karhunen–Loeve expansion is computationally equivalent to using wavelet directly for stochastic expansion and simulating the correlated random coefficients using eigen decomposition. An alternate but longer wavelet expansion using Cholesky decomposition is shown to be of comparable accuracy. When simulation time dominates over initial overhead incurred by eigen or Cholesky decomposition, it is potentially more efficient to use a shorter truncated K–L expansion that only retains the most significant eigenmodes. [Copyright &y& Elsevier]

To check the doping mechanism of trivalent ion doping in PbWO4 (PWO) and verify the formation of dipoles [2MPb3+–VPb], the researches on an investigation of tetravalent ion (Th4+, Zr4+) doped PWO was conducted by dielectric loss spectroscopy, thermoluminescence and optical absorption spectroscopy. The doping mechanism of tetravalent ion doping is similar to that of trivalent ion doping, while the dipole defects should be formed more easily due to the convenience for the two defects VPb and MPb4+ to get close to each other. However, in the case of Zr4+ doping, Zr was found to enter interstitial sites because of its small ionic radius, with the introduced charges compensated by VPb far away and hence does not exert an obvious influence on the performance of this material. Thus, no dielectric relaxation was found in the DS (dielectric spectra) experiment. [Copyright &y& Elsevier]

Although a slope may have numerous potential slip surfaces, its failure probability is often governed by several representative slip surfaces (RSSs). Previous efforts mainly focus on the identification of circular RSSs based on limit equilibrium methods. In this paper, a method is suggested to identify RSSs of arbitrary shape based on the shear strength reduction method. Monte Carlo simulation is used to generate a large number potential slip surfaces. The RSSs are identified through analyzing the failure domains represented by these samples. A kriging-based response surface model is employed to enhance the computational efficiency. These examples shows that the RSSs may not always be circular, and that the suggested method can effectively locate the RSSs without making prior assumptions about the shape of the slip surfaces. For the examples investigated, the system failure probabilities computed based on the shear strength reduction method are comparable to, but not the same as those computed based on the limit equilibrium methods. The suggested method significantly extends our capability for identifying non-circular RSSs and hence probabilistic slope stability analysis involving non-circular slip surfaces. [ABSTRACT FROM AUTHOR]

Although numerical models have been widely used in the geotechnical profession, their applications for reliability analysis are still rather limited mainly because most geotechnical numerical programs lack the probabilistic function. In this study, an efficient response surface method is suggested for geotechnical reliability analysis using existing numerical programs. The developed approach can effectively avoid the occurrence of negative values for positive random parameters, and thus it solves the key limitation of the classical response surface method in geotechnical applications. To facilitate its application, a procedure is designed for automating reliability analysis with the commercially available program, FLAC3D. The developed method and procedure are demonstrated in detail using a slope example. The versatility of the suggested procedure is illustrated through the serviceability reliability analysis of a soft ground improved with deep mixing columns. For the reinforced ground studied in this paper, the reliability is mainly governed by the uncertainties in Young’s moduli of the soil and reinforced columns. The suggested method can be conveniently used for reliability-based design of deep mixing columns. [ABSTRACT FROM AUTHOR]

Abstract: A coupled elastoplastic damage model is proposed for the description of strongly anisotropic sedimentary rocks. In order to describe the inherent anisotropy of the material, a scalar anisotropy parameter is introduced using the concept of fabric tensor. Using this parameter, an anisotropic plastic model is formulated taking into account influence of loading orientation. Plastic deformation is then coupled with induced damage by growth of microcracks. The proposed model is applied to typical sedimentary rock; Tournemire shale. The procedure for model’s parameters identification is presented. A series of numerical simulations are performed for triaxial compression tests performed with different confining pressures and various loading orientations. Comparisons between numerical predictions and experimental results show that the proposed model is capable to reproduce the main features of mechanical behavior of strongly anisotropic rocks. [Copyright &y& Elsevier]

Abstract: This study addresses the influence of elevated pressures up to 1.6MPa on the flame geometry and the flickering behavior of laminar diffusion flames and particular attention has been paid to the effect of fuel variability. It has been observed that the flame properties are very sensitive to the fuel type and pressure. The shape of the flame was observed to change dramatically with pressure. When the pressure increases, the visible flame diameter decreases. The height of a flame increases first with pressure and then reduces with the further increase of pressure. The cross-sectional area of the flame (A cs) shows an average inverse dependence on pressure to the power of n (A cs ∝ P−n ), where n =0.8±0.2 for ethylene flame, n =0.5±0.1 for methane flame and n =0.6±0.1 for propane flame. It was observed that the region of stable combustion was markedly reduced as pressure was increased. High speed imaging and power spectra of the flame chemiluminescence reveal that an ethylene flame flickers with at least three dominant modes, each with corresponding harmonics at elevated pressures. In contrast methane flames flicker with one dominant frequency and as many as six harmonic modes at elevated pressures. [Copyright &y& Elsevier]

A new sorbent system for removing heavy metal ions, such as Zn(II), Cu(II) and Pb(II), from aqueous solutions has been investigated. This new sorbent is tree fern, an agriculture product. Variables of the system include solution temperature and sorbent particle size. The experimental results were fitted to the Langmuir, Freundlich and Redlich–Peterson isotherms to obtain the characteristic parameters of each model. Both the Langmuir and Redlich–Peterson isotherms were found to well represent the measured sorption data. According to the evaluation using the Langmuir equation, the maximum sorption capacities of metal ions onto tree fern were 7.58 mg/g for Zn(II), 10.6 mg/g for Cu(II) and 39.8 mg/g for Pb(II). It was noted that an increase in temperature resulted in a higher metal loading per unit weight of the sorbent. Decreasing the particle sizes of tree fern led in an increase in the metal uptake per unit weight of the sorbent. [Copyright &y& Elsevier]

Site investigation is widely used for uncertainty reduction and design improvement in slope engineering. Before the site investigation is implemented, it is important to assess and compare the effectiveness of different site investigation programs. In this paper, an efficient method for analyzing the effectiveness of a site investigation program for slope stability assessment through value of information analysis is proposed. In this method, a logistic regression model is developed to approximate the relationship between failure probability of the slope and the site investigation data, through which the evaluation of posterior distribution and slope reliability analyses are both avoided. The suggested method is illustrated and verified with an example. For the example studied in this paper, the number of slope stability analyses required is only 1% of that reported in the literature. The suggested method can be used to study the effects of locations of the boreholes, the number of boreholes, and the depth of boreholes on the effectiveness of a site investigation program. [ABSTRACT FROM AUTHOR]

This paper suggests a new set of analytical solutions for predicting the effect of grouting on ground and shield tunnel behaviour as a consequence of steady water inflow into a tunnel in saturated clay. These solutions allow the effects of the tunnel lining and grouting material to be considered on the basis of their relative permeability to the surrounding soil. Moreover, the equivalent permeability of the tunnel lining can be derived based on the water inflow rate, which is commonly assumed to be proportional to the soil permeability in a typical analysis. A comparison of the results of analytical and numerical simulations indicates that the solutions are sufficiently accurate for tunnel applications. The effect of grouting material on the tunnel-leakage-induced seepage field, ground and tunnel settlements, internal forces and tunnel convergence of the shield tunnel are examined with the verified solutions. Based on the analytical results, the effect of grouting material on the tunnel leakage appears to depend on the permeability of the tunnel lining. Thus, a dimensionless parameter RP slg integrating the permeability and geometry of the tunnel lining and grouting material is proposed to quantitatively describe the effect of the grouting material on tunnel leakage. Using RP slg , the effect of the grouting material on tunnel leakage can be easily derived. Indeed, the analytical results show that tunnel leakage produces significant ground and tunnel settlement. The grouting can clearly reduce the effect of tunnel leakage on tunnel and ground settlement when the relative permeability of the grouting material and soil k g / k s is less than 0.01. Moreover, the increase in the tunnel-leakage-induced bending moment and the decrease in hoop thrust are generally small but this may increase the permeability of the tunnel joints. The leakage-induced tunnel convergence is small and is therefore unlikely to degrade the serviceability or safety of a tunnel. [ABSTRACT FROM AUTHOR]

Abstract: Geotechnical models are usually associated with considerable amounts of model uncertainty. In this study, the model uncertainty of a geotechnical model is characterised through a systematic comparison between model predictions and past performance data. During such a comparison, model input parameters (such as soil properties) may also be uncertain, and the observed performance may be subjected to measurement errors. To consider these uncertainties, the model uncertainty parameters, uncertain model input parameters and actual performance variables are modelled as random variables, and their distributions are updated simultaneously using Bayes’ theorem. When the number of variables to update is large, solving the Bayesian updating problem is computationally challenging. A hybrid Markov Chain Monte Carlo simulation is employed in this paper to decompose the high-dimensional Bayesian updating problem into a series of updating problems in lower dimensions. To increase the efficiency of the Markov chain, the model uncertainty is first characterised with a first order second moment method approximately, and the knowledge learned from the approximate solution is then used to design key parameters in the Markov chain. Two examples are used to illustrate the proposed methodology for model uncertainty characterisation, with insights, discussions, and comparison with previous methods. [Copyright &y& Elsevier]

Abstract: We evidenced an early-stage ordering (ESO) in Fe51Pt49 film before the appearance of superlattice diffraction (long-range-order, LRO) using 40-nm-thick films prepared by magnetron sputtering onto quartz substrate. The appearance of L10 phase for samples deposited at substrate temperatures (T s) 400°C and higher was verified by X-ray diffraction. Surface roughness of Fe51Pt49 films, obtained via X-ray specular reflectivity with computational fitting, increases from 3.8 to 11Å as T s is increased from 25 to 275°C. As further increase of T s to 375°C, the roughness drops to 3.2Å and then increases again to 38Å with T s up to 700°C. Measurement on residual strain demonstrates that it is initially compressive at T s<400°C. Thereafter the strain transfers to a tensile one and increases in magnitude as increasing T s up to 700°C corresponding to LRO transformation. Local atomic rearrangement is observed for samples deposited at T s>250°C by using extended X-ray absorption fine structure. Coercivity of films increases from 10 to 460Oe as T s increase from 25 to 375°C (ESO) and then from 460 to 10,700Oe with T s 375–700°C (normal LRO). The worked out quantitative estimation of ESO engages with that of LRO before T s 400°C. [Copyright &y& Elsevier]