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To compare the quality of life (QOL), cosmesis and cost-utility of open surgery (OS), vacuum-assisted breast biopsy (VABB) and high intensity focused ultrasound (HIFU) for fibroadenoma (FA). A total of 162 patients with 267 FAs were enrolled. Baseline characteristics and treatment information were recorded. Patients were followed up at 3-, 6- and 12-month post-treatment. QOL was evaluated by health survey. Breast cosmesis was evaluated by self-rating survey and Harvard Scale. A decision-analytic model was established and incremental cost was calculated for cost-utility analysis. For QOL evaluation, there was no difference of physical component summary (PCS) score in three groups (P > 0.05), while the mental component summary (MCS) score was significantly higher in HIFU group than the other two groups at 3- and 6-month post-treatment (P < 0.05). The proportion of patients satisfied with breast cosmesis was significantly higher in HIFU group (96.49%) than in VABB group (54.90%) and OS group (49.99%) (P < 0.05). By Harvard Scale, 27.78%, 78.42% and 100.00% of patients were rated as excellent and good in OS group, VABB group and HIFU group, respectively (P < 0.05). To acquire a quality-adjusted life year (QALY), cost of OS, VABB and HIFU was 1034.31 USD, 1776.96 USD and 1277.67 USD, respectively. When compared to OS, incremental cost analysis showed HIFU was cost-effective, while VABB was not. OS, VABB and HIFU were all effective and safe for FA, but among these three treatments, HIFU had the best QOL improvement, breast cosmesis and cost-effectiveness. [ABSTRACT FROM AUTHOR]

Abstract The compositional window leading to the crystallization of primary α-Nb phase and the eutectic (α-Nb + TiCo) phase in Nb-Ti-Co alloys is of high technical relevance due to its favourable properties with respect to hydrogen permeation. To this end, a new compositional window for hydrogen-permeable Nb-Ti-Co alloys is discussed and established for the first time in this study. It is found that improving the hydrogen permeability and increasing the durability are in contradiction with each other, and are closely related to the alloy composition. Optimization of the design of these alloys is therefore a compromise between above-mentioned two parameters. As-cast Nb 45 Ti 25 Co 30 shows a good balance between permeability and durability. Secondly, Nb-Ti-Co amorphous (a -) membranes have been successfully prepared by the melt-spinning technique. The importance of the annealing condition in determining crystallization behaviour, hydrogen permeability and durability is brought out. Subsequent annealing decreases the hydrogen permeation flux of the a - membrane, but significantly increases its thermal stability and durability, compared with its amorphous state, which is attributed to the microstructural change from amorphous to a duplex structure. Typically, a - Nb 30 Ti 35 Co 35 membrane after annealing at 1000 °C for 12 h shows a high hydrogen permeation flux of 15.55 cc H 2 cm−2 min−1 and excellent durability of ~ 112 h at 400 °C. Thirdly, the permeability of crystallized (c -) Nb 30 Ti 35 Co 35 membrane obtained by annealing at 1000 °C for 12 h towards hydrogen was tested and evaluated under the mixed atmosphere of H 2 /CO or H 2 /CO 2. This membrane possesses a relative stable H 2 flux and good durability without corrosion/chemical reaction-induced failure. The present work demonstrates that Nb-Ti-Co amorphous alloys followed by proper annealing are an attractive candidate material for hydrogen separation membrane. Highlights • A new compositional window for hydrogen permeable Nb-Ti-Co alloys is established. • Permeability/durability can be optimized by adjusting the alloy composition. • Nb 30 Ti 35 Co 35 amorphous membranes were successfully fabricated. • A H 2 flux of ~ 15.55 cc H 2 cm−2 min−1 is derived for the c - Nb 30 Ti 35 Co 35. • The c - Nb 30 Ti 35 Co 35 exhibits robust H 2 flux for gas mixture. [ABSTRACT FROM AUTHOR]

Effect of Pd overlayer and mixed gases on hydrogen permeation of Pd/Nb 30 Hf 35 Co 35 /Pd composite membranes was investigated. The diameter of Pd particle increases with increasing sputtering power. With this change, the membrane shows a signification reduction in hydrogen permeability/or flux, but its durability and stability increases significantly, which can be mainly attributed to a decrease in hydrogen solubility coefficient. In addition, H 2 S impurity in mixed gases can greatly degrade membrane performance, especially the hydrogen permeability, whereas the Ar impurity content has less effect in the temperature range of 523–673 K. Lowering of permeability caused by the change of gas purity can be attributed to a decrease in hydrogen solubility, which is closely related to the stronger adsorption of H 2 S molecules to the Pd overlayer of the membrane. Thus, it is concluded that aside from the optimum design for composition of Nb-based hydrogen permeable alloy to improve their permeability, the control of Pd overlayer film on membrane surface and gas purity in the feed gas is important. [ABSTRACT FROM AUTHOR]

Our recent work has shown that vanadium carbide (VC) films prepared by radio frequency magnetron sputtering (RFMS) can be used as H 2 dissociation/recombination catalysts on vanadium (V) for high temperature hydrogen separation. During the deposition of VC on V by RFMS, substrate bias was further applied to tune the microstructure and hydrogen permeability of the VC/V composite membranes. It is found that moderate substrate bias during RFMS generates nanocrystalline VC films with hexagonal close packed V 2 C (hcp-V 2 C) phase, which exhibits finer grain size and higher carbon vacancy density compared to the films with face centered cubic VC (fcc-VC) phase prepared by RFMS without bias. The increase in carbon vacancy density results in an increase in the electron density around the Fermi level (E F) and a lowering of the d-band center for the VC, which contributes to its catalytic activity. The resulted VC/V composite membranes show significantly enhanced hydrogen permeability, particularly at all temperatures evaluated, above that of industrially used Pd. This work demonstrates that RFMS with applied substrate bias as microstructural engineering is an efficient method to prepare highly hydrogen-permeable VC/V composite membranes. [Display omitted] • RFMS with bias generates VC films with finer grain size and higher carbon vacancy density. • RFMS with bias acts as structural engineering to enhance the catalytic activity of VC films. • VC/V membranes prepared by RFMS with bias exhibit obviously enhanced hydrogen permeability. • RFMS with bias is an efficient method to prepare highly hydrogen-permeable VC/V membranes. [ABSTRACT FROM AUTHOR]

Experimental investigations on heat transfer of supercritical pressure aviation hydrocarbon fuel RP-3 in a horizontal miniature round tube were conducted. The influence of buoyancy on heat transfer of RP-3 was studied. Buoyancy effect is particularly significant in horizontal flows, which leads to non-uniform temperature distributions in cross section of the test section even for the miniature round tube. The buoyancy effects of heat transfer can be well evaluated by the non-dimensional parameter Gr q / Gr th developed by Petukhov. And this criterion was first tested for the horizontal flow in miniature round tube under supercritical pressure conditions. At last, this paper proposed a correlation of Nusselt number for supercritical pressure aviation fuel in the horizontal tube. [ABSTRACT FROM AUTHOR]

This article presents convective heat transfer of hydrocarbon fuel RP-3 at supercritical pressures in vertical micro-tubes with inner diameters of 0.538 mm, 1.09 mm and 1.82 mm under heating conditions. Effects of system pressure, heat flux, mass flow rate and flow direction were experimented and analyzed with wide range of supercritical status. Also, inner diameter effect on heat transfer were compared at identical conditions. The results indicate that sharp variation of thermal properties with temperature is the key factor to influence heat transfer. Normal, deterioration and enhancement heat transfer phenomena generally occur in turn along with dimensionless position. Moreover, Nusselt number variation shows good agreement when the contrast temperature T b / T pc is lower than 0.80 and Bo ∗ = 1.0 × 10 −8 could be the critical point to evaluate buoyancy influence. At last, two well-predicted empirical correlations of Nusselt number are proposed for downward and upward flow heat transfer in 1.09 mm tube. [ABSTRACT FROM AUTHOR]

Railway intrusion detection is important for the safety of the railway operation. However, how to detect intruding events in the scene of unmanned aerial vehicle (UAV) surveillance is a challenging task, especially when there are multiple railway regions or unknown types of intruding objects. To tackle the above problems, a railway intrusion detection method is proposed for the scene of UAV surveillance. It can detect intruding events accurately without pre-setting the intruding object type by detecting the normal railway region and the abnormal railway region with intruding objects rather than recognizing the intruding objects directly. The proposed network consists of a novel Fused-convolutional long short-term memory (Fused-ConvLSTM) module for efficiently propagating spatial and temporal information; several attention modules for adaptively enhancing the feature information, such as the improved feature fusion layer; several lightweight strategies for reducing the computation complexity, such as lightweight feature extraction and width multiplier. Experiments are performed on the real aerial videos obtained by a micro UAV. The experimental results demonstrate that the proposed method can accurately detect railway intrusion events in aerial video, and effectively deal with the case of multiple railway regions and unknown intruding object types. The experimental results also demonstrate that the proposed network can achieve better performance than other object detection networks. • A novel deep learning-based railway intrusion detection method for UAV surveillance scenes is proposed without pre-setting the intruding object type. • A novel convolutional LSTM module called Fused-ConvLSTM is proposed. • An improved feature fusion layer is proposed. • An improved railway clearance intrusion detection network is proposed. • The experiments results based on real aerial videos demonstrate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

• AI-acceptability is biased due to customer's cultural proximity with human producers. • The importance of being human leads to the depreciation of the perceived quality of AI-products. • Ignoring this bias can lead to over-optimistic returns to AI-investment expectations. Artificial intelligence (AI) can generate a greater number of recombinations of ideas than humans can, and hence AI-produced creative products could be seen as embodying more innovation and surprise which are worth higher economic value. Yet the lack of human emotionality embedded in an AI product deprives it of an essential 'humanness' to which people attach important cultural value. As the overall value of a product is a sum of its economic and cultural values, we assessed the demand differential and quality perception asymmetry of creative products, specifically music compositions, that have been created by humans and AI separately. We conducted a survey with a quasi-experimental design and found that respondents reveal lower valuations towards music generated by AI and will moderate their evaluations of quality away from AI- and towards human-generated compositions when the type of composer is known. The demand for creative goods is sensitive to consumers' perceptions of cultural proximity to humanness that determine the acceptability of AI products. [ABSTRACT FROM AUTHOR]

AB 2 Sb 2 -type Zintl phases, especially Mg 3 Sb 2 , have garnered widespread attention in virtue of their nontoxic constituent elements and outstanding thermoelectric performance in n-type materials. However, the p-type counterpart of AB 2 Sb 2 still struggles with a low figure of merit zT , primarily because of the limited valence band degeneracy, large band effective mass, and relatively high thermal conductivity. Here we simultaneously optimize the electrical and thermal transports of p-type AB 2 Sb 2 -based materials through shaping the band edge and distorting the crystal lattice. By alloying Zn at Mg2 site and Ca at Mg1 site, we successfully decorate the crystal lattice of Mg 3 Sb 2 in real space and thereby modify the band structure in reciprocal space. Zn alloying promotes the band degeneracy while Ca alloying reduce the single band effective mass, which largely promotes the transport of charge carriers. Moreover, the distorted crystal lattice effectively blocks the heat-carry phonons to reduce the lattice thermal conductivity κ L. A high zT of 0.81 is finally realized at 750 K in our Zn/Ca co-alloyed samples, which is three times larger than that of Mg 3 Sb 2 matrix. Our work opens new possibilities for the synthetic optimization of both electrical and thermal transports in Zintl phase and other thermoelectric systems. We achieved a high power factor of 8.3 μW cm-1 K-2 and an ultralow κ L of 0.52 W m-1 K-1 in Mg 3–3 x Zn 2 x Ca x Sb 2 solid solutions through band shaping and lattice distortion engneering. [Display omitted] [ABSTRACT FROM AUTHOR]

Multiphase Nb x Ti (100-x)/2 Co (100-x)/2 (x = 30–60) alloys are a promising material for hydrogen separating membranes. These alloy membranes exhibit a rapid decline in hydrogen permeation flux within ∼12 h when operated at 773 K. To address this issue, a dense oxide (e.g. Nb 2 O 5 , TiO 2 and CoO) layer was prepared between a Pd coating layer and an Nb–TiCo substrate by surface corrosion for improving their thermal stability, and the corrosion resistance of Nb–TiCo alloys was investigated. An increase in the Nb content (x) lowers the corrosion resistance of these alloys, but makes it easier to form the above oxide layer. Substantial enhancement of hydrogen permeability and thermal stability at 773 K was observed for the alloys (x = 30 and 40) after corrosion, which can be ascribed to an increase in hydrogen diffusivity. This improved permeability and stability are closely related to the formation of the above surface oxide layer that impeded interdiffusion between the Pd film and Nb–TiCo substrates. This study demonstrates that insertion of a diffusion barrier between the Pd and Nb-based substrates by surface corrosion is a viable approach to enhance the high-temperature stability of Pd-coated Nb–TiCo alloys, an aspect not widely explored in Nb-based hydrogen separation and purification membranes. • Dense intermediate oxide layer was prepared between Pd coating and the substrate. • Durability/permeability can be optimized by placing an inter-layer. • Nb 30 Ti 35 Co 35 with an oxide layer exhibits an excellent durability of ∼1053 min. • A high Φ value of 4.56 × 10−8 mol H 2 m−1s−1Pa−0.5 is derived for Nb 30 Ti 35 Co 35 at 773 K. • The variation of Φ is due to the change in D rather than K. [ABSTRACT FROM AUTHOR]

In the Cu-2.5Fe-0.3Cr-0.3 Mg-0.2Si-0.1Ca-0.1Zr alloy, a double-scale (micro and nano) FeCrSi second phase has been generated. The orientation relationship between nano-precipitates and the matrix is: (111)Cu//(202)Fe x Cr (3- x) Si, 1 1 ¯ 0 Cu// 1 1 ¯ 1 ¯ Fe x Cr (3- x) Si. The influence of the thermomechanical treatment process on the microstructure, mechanical properties and electrical conductivity of the alloy is explored. Results indicate that the final alloy has excellent properties. The hardness, yield strength, tensile strength and electrical conductivity of the final alloy are 204 HV, 635 MPa, 649 MPa and 63.57 %IACS, respectively. The calculations show that precipitation strengthening and dislocation strengthening have essential contributions to the strength of the final alloy. The former mainly comes from the strengthening effect of the FeCrSi nano-precipitates, and the latter is related to the multi-stage thermomechanical treatment process. • A novel high-strength and high-conductivity Cu-2.5Fe-0.2Si-0.3 Mg-0.1Ca-0.3Cr-0.1Zr alloy is designed. • A double-scale (micro and nano) FeCrSi second phase has been generated in the designed alloy. • FeCrSi nano-precipitates have a remarkably significant contribution to the strength of the alloy. • The tensile strength and electrical conductivity are 649 MPa and 63.57 %IACS, respectively. [ABSTRACT FROM AUTHOR]

In recent years, many image denoising methods have been proposed based on convolutional neural networks (CNNs). While these methods have shown continuous performance improvement by introducing various mechanisms and structures, their computational cost tends to become increasingly expensive, owing to the resulting complex network architectures. This paper aims at winning the trade-off between computational efficiency and denoising performance for CNN-based image denoisers. Towards this end, we draw inspirations from traditional variational models with wavelet analysis operators for CNN architecture design. A model-inspired CNN is proposed with four key modules: iterative encoding-decoding units inspired by the iterative denoising process, directional convolutions inspired by the separable wavelet filters, inception modules inspired by the multi-scale analysis of wavelets, and stage-wise connections inspired by the adding noise back operation. In experiments, our CNN shows high computational efficiency in both training and test, with competitive results to state-of-the-art approaches. • A neural network inspired by the key ingredients of wavelet analysis model. • A sequential encoding-decoding network for image denoising. • A deep image denoiser well balancing effectiveness and computational efficiency. [ABSTRACT FROM AUTHOR]

Ag–Bi 2 WO 6 –TiO 2 (ABT) ternary composite photocatalyst was prepared using solvothermal and surface deposition method. Then, the nano photocatalyst was doped into the starch film liquid through internal loading method, and finally, ABT/starch composite film was constructed using tape casting method for visible light catalytic degradation of ethylene. Characterize and analyze the structure and physical properties of nano ABT/starch composite membranes prepared with different ABT loading amounts, and optimize the reaction conditions (ABT addition amount, light intensity, initial concentration of ethylene) on the visible light catalytic degradation performance for ethylene of the composite membrane. The results show that the nano ABT particles and starch molecules have good biocompatibility, and they can be well fused to form a film, without changing the crystal structure of ABT and generating other chemical bond. The results of photocatalytic degradation of ethylene showed that when the loading amount of ABT was 5 wt%, the light intensity was 60.5 mw/cm2, and the initial concentration of ethylene was 0.15 mg/L, the ABT/starch film had the best ethylene degradation performance, with a K′ value of 5.6111 × 10−4 min−1, which is 17.9 times that of the blank starch film. Under the optimal preparation conditions, the thickness, tensile strength, elongation at break of the starch composite film is 168.33 μm, 5.01 Mpa, 32.4%, respectively, and the maximum thermal decomposition temperature is 320.5 °C, which meets the requirements for food packaging materials. After 4 cycles, the catalytic degradation of ethylene by starch composite membrane only decreased by 13.98%, indicating good reusability. [ABSTRACT FROM AUTHOR]

Herein, a scalable and facile strategy is presented to fabricate ultra-small nickel phosphide nanoparticles loaded reduced graphene oxide on nickel foam (Ni 2 P/RGO@NF) through an interfacial redox reaction between GO and NF in water, followed by a simple phosphorization process. This self-supported Ni 2 P/RGO@NF catalyst with favorable 3D hierarchical nanostructure, enhanced electrical conductivity and high density of ultra-small Ni 2 P (24,000 particles per square micron) shows outstanding bifunctional catalytic performance toward overall water splitting under alkaline and neutral conditions. Notably, the Ni 2 P/RGO@NF electrode delivers low cell voltage of just 1.58 V and 1.68 V at a current density of 10 mA cm−2 in alkaline and neutral electrolytes with prominent stability for more than 20 h, respectively. Moreover, ultra-small cobalt phosphide loaded RGO on cobalt foam samples have also been prepared by the same method. Thus, this strategy provides a general way for fabricating self-supported electrocatalysts with ultra-small metal-based nanoparticles, which is scalable and applicable in energy storage and conversion devices. Image, graphical abstract [ABSTRACT FROM AUTHOR]

Surface coking deposition influences on flow and heat transfer of aviation kerosene RP-3 in helical tubes were experimentally investigated at supercritical pressure. Four types of helical tubes with fixed pitch and various helical diameters have 1.86 mm inner diameter and 2.2 mm outer diameter. The system pressure, inlet temperature, mass flow rate were fixed at 5 MPa, 400 K and 1178 kg/m 2 s, respectively. The results indicate that the helical centrifugal force could inhibit the thermal oxidation coking and slow down the growth rate of press drop within maximum value of 47.6%. For the same cross section, the outer heat transfer coefficient (HTC) decreases gradually and eventually is less than the inner side due to coking deposition. Finally, a correlation of Nusselt number considering coking deposition was simulated to predict the heat transfer characteristics. [ABSTRACT FROM AUTHOR]