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In a previous paper by the authors, the computational expressions for the higher order terms of the radiative perturbation series have been developed, and numerical results have been obtained. In this paper, new computational expressions are developed that use the analytic Green''s function and the GDOM code, which were developed recently by Qin and Box. Our analysis and numerical computations indicate that the new scheme dramatically improves the efficiency of the computation (by reducing the CPU-time to less than 2% of that required by the previous scheme), and the huge demand on memory usage has been completely removed. This new scheme allows us to expand the high order perturbation computations to more general cases, for example, to include azimuth dependence, and to use the perturbation theory in more potential applications. [Copyright &y& Elsevier]

Numerical solutions to the nonlinear coupling-wave equations of second harmonic (SH) and third harmonic (TH) generators are investigated for both phase matched and phase mismatched configurations. For phase mismatched TH generation, several kinds of schemes (the phase mismatch either in second harmonic generation (SHG) or sum-frequency generation (SFG) process) are considered and analyzed. The physical nature corresponding to the different ratios of the coupling coefficients is discussed. [Copyright &y& Elsevier]

We make an analysis of the distribution of the extensive Doppler redshift defined as with a sample of 1317 absorption redshifts available from 401 quasars. The analysis reveals a bi-peak structure in the distribution, with one component located at and the other at . A study of some possible causes suggests that the structure can be well interpreted: while the absorbers inside the same cluster as the quasar concerned could contribute to the first component and the less populated space between clusters could explain the gap between the two peaks, the typical distance between clusters could account for the second component. If the bi-peak structure is real, which needs to be confirmed by complete samples, one would be able to obtain some useful cosmological information. [ABSTRACT FROM AUTHOR]

In an accompanying paper, we develop the computational expressions for the higher order perturbation of the radiative transfer equation, and present some numerical results for typical cases. In this article, we discuss a number of issues regarding the implementation of the HOP computation: obtaining the Green''s function, its expansion as a double series of Legendre polynomials, and obtaining the adjoint radiance of more general sources such as those for the fluxes at arbitrary altitudes. Examples of Green''s function and its expansion coefficients are presented. [Copyright &y& Elsevier]

As a computationally effective tool, the first-order term of the radiative perturbation theory has been computed successfully, and has been applied in a number of areas. In this article, we develop the computational expressions for the higher-order terms of the perturbation expansion in a plane parallel atmosphere. These expressions are then implemented, and numerical results for some typical cases are presented. These results indicate that the computation is successful and that the higher-order terms are essential in cases where the first-order term alone cannot predict the perturbation with sufficient accuracy. [Copyright &y& Elsevier]

Fluid flow that arises from the functional loading of bone tissue has been proposed to be a critical regulator of skeletal mass and morphology. To test this hypothesis, the bone adaptive response to a physiological fluid stimulus, driven by low magnitude, high frequency oscillations of intramedullary pressure (ImP), were examined, in which fluid pressures were achieved without deforming the bone tissue. The ulnae of adult turkeys were functionally isolated via transverse epiphyseal osteotomies, and the adaptive response to four weeks of disuse (n=5) was compared to disuse plus 10 min per day of a physiological sinusoidal fluid pressure signal (60 mmHg, 20 Hz). Disuse alone resulted in significant bone loss (5.7±1.9%, p&les;0.05), achieved by thinning the cortex via endosteal resorption and an increase in intracortical porosity. By also subjecting bone to oscillatory fluid flow, a significant increase in bone mass at the mid-diaphysis (18.3±7.6%, p<0.05), was achieved by both periosteal and endosteal new bone formation. The spatial distribution of the transcortical fluid pressure gradients (∇Pr), a parameter closely related to fluid velocity and fluid shear stress, was quantified in 12 equal sectors across a section at the mid-diaphyses. A strong correlation was found between the ∇Pr and total new bone formation (r=0.75, p=0.01); and an inverse correlation (r=−0.75, p=0.01) observed between ∇Pr and the area of increased intracortical porosity, indicating that fluid flow signals were necessary to maintain bone mass and/or inhibit bone loss against the challenge of disuse. By generating this fluid flow in the absence of matrix strain, these data suggest that anabolic fluid movement plays a regulatory role in the modeling and remodeling process. While ImP increases uniformly in the marrow cavity, the distinct parameters of fluid flow vary substantially due to the geometry and ultrastructure of bone, which ultimately defines the spatial non-uniformity of the adaptive process. [Copyright &y& Elsevier]

FE simulations were conducted to assess the scale of friction-dependent pressure losses in the injection chamber during the injection forging of solid and tubular components. Several lubrication procedures were then tried with a view to establishing the “optimal” lubrication which would result in a significant reduction of the friction in the injection chamber. A procedure which combined two lubricants was identified as being “optimal” for use in the extrusion of long, shaft-type components. The procedure enabled the pressure losses in the injection chamber to be reduced from 50 to 60% of the applied pressure to 4–6% of the pressure. Experiments and FE simulations of the forming of the tubular components confirmed the significant reduction of the forming force requirement and the improvement of the material flow by the developed procedure. [Copyright &y& Elsevier]

Analysis of surface deformation is of particular significance to research in surface engineering, but previous surface models, however, could not meet application-requirements in the elastic–plastic analysis of engineering components. A statistical FE surface model was, therefore, developed to simplify the analytical procedure. An “equivalent asperity”, which is a statistical representation of the surface, was used to determine the deformation of the surface: this enabled the computation of the surface roughness of a surface that had been subjected to compression. The computed roughness was compared to the measured data to validate the developed model. The result suggested that the model is sufficiently accurate for use in the prediction of the surface character of materials that have been subjected to interfacial pressure. [Copyright &y& Elsevier]

A novel roller form, a deep end-cavity roller, is proposed for roller-type bearings, with a view to reducing the weight of the structure and the centrifugal forces acting on the outer race of the bearing, and reducing the sensitivity of the bearing performance to the manufacturing precision. FE simulation results suggest that the new design would enable a straight-profile-roller bearing to have a similar performance to that for a logarithmic-profile roller bearing, as the deep end-cavity roller eliminates the sharp edge-stresses at the two apexes of the roller. Compared with the manufacture of a logarithmic-profile roller, the manufacture of a straight-profile deep end-cavity roller is simpler, and less strict on manufacturing precision. The deep end-cavity roller also enables an “in-process” correction of the contact-stress distribution between the roller and the raceway. [Copyright &y& Elsevier]

Design for hydromechanical deep drawing of sheet components with concave features requires more detailed considerations than that for the forming of components with convex features. FE simulations were conducted to examine the deformation of the sheet during the forming of these component-forms and to qualify the influence of counter-pressure paths on the product-quality, with a view to developing a reference for process, tool and component design considerations for the hydromechanical drawing of such component-forms. The results suggested that in order to prevent the initiation of forming-defects and to achieve high-quality products, the counter-pressure paths should be designed to match the component-forms to be produced. [Copyright &y& Elsevier]

Injection forging is a nett-shape manufacturing process which enables the forming of complex component-forms that are difficult to form by conventional metal-conversion processes. The state-of-the-art of the research in this subject is reviewed with reference to different process configurations, forming limits, energy/pressure requirements, process modelling and product forms. [Copyright &y& Elsevier]

The Manufacturing Engineering Research Centre (MERC) of the University of Strathclyde is one of several locations for the research and development of high-precision material-conversion processes: the focus at MERC has been on the development of experimental and numerical simulation techniques, new forming-configurations and the development of industrial applications. Current efforts concentrate on conventional forging, injection forging, precision-blanking, vibration-assisted forging and micro-forming. This paper reviews the findings of MERC and appraises the prospects of the application of the research. Future programmes of research are also defined. [Copyright &y& Elsevier]

As an accurate and efficient algorithm, the discrete-ordinate method (DOM) has been used to solve the radiative transfer problem of plane-parallel scattering atmosphere illuminated by a parallel beam, an idealized case of the sun, from above the atmosphere. In this paper, we extend this algorithm so that radiative problems of more general sources, such as parallel surface sources that illuminate with a parallel beam in any direction from any vertical position, and general surface sources that illuminate continuously in a hemisphere, can be solved. For a problem where intensity distributions are sought for a number of different sources within the same atmosphere-surface system, the intrinsic properties of DOM are used so that the time required for the solution for extra sources is reduced to a substantially small amount. In the case of parallel surface sources, numerical testing has shown that the amount can be reduced to as little as 15% of a full solution. Examples of applications are presented. [Copyright &y& Elsevier]

Investigates the role of guanosine triphosphatase Ras and Rap control adenylic acid receptor trafficking in activity-dependent synaptic plasticity. Pairing-induced long-term potentiation in neurons; Independent regulators for potentiating and depressing central synapses; Activation of endogenous Ras signalling pathway of spontaneous activity.

Presents information on a study which derived the basic formula in calculating the real speed and angle of the line of sight of the galactic superluminal sources. Use of proper component motions; Mathematical equations; Conclusions.

Provides information on a study which investigated whether K-correction had a strong impact on the Alpha[subro] - Alpha[subox] color-color diagram of BL Lacertae objects and its classification. Kinds of objects; Application of all values of radio, optical and X-ray fluxes available for the sources; Results of the study.

• CAE is first designed as the feature extractor to mine the fault features. • Both CORAL loss and domain classifier loss are integrated for domain adaptation. • A new fault transfer diagnosis model called CAE-DTLN is constructed. • The proposed model can be well applied to mechanical fault transfer diagnosis. Deep learning has gained a great achievement in the intelligent fault diagnosis of rotating machineries. However, the labeled data is scarce in actual engineering and the marginal distribution of data is discrepant under different conditions. Transfer learning provides a feasible way to overcome these difficulties. Considering the effect of noise on the transfer fault diagnosis, this work puts forward a new deep transfer learning network based on convolutional auto-encoder(CAE-DTLN) to implement the mechanical fault diagnosis in target domain without labeled data. In the proposed framework, CAE is used as the feature extractor as it has the ability of noise removal. Moreover, both CORrelation ALignment (CORAL) loss and domain classification loss are integrated to enhance the effect of domain confusion. The proposed model is applied to the fault transfer diagnosis of planetary gearboxes under different working loads and noise levels, and it is compared with other typical fault transfer diagnosis models. The experimental results show that CAE-DTLN has higher diagnosis accuracy and stronger generalization ability. The average diagnostic accuracy of CAE-DTLN is over 99%. Moreover, the proposed transfer learning model has better anti-noise performance. [ABSTRACT FROM AUTHOR]

• A new expanded graphite ribbon (EGR) is obtained by compressing a single piece of expanded graphite. • The EGR has a micrometer-sized thickness and a millimeter-sized length. • The thermal conductivity of EGR is measured accurately using a variable-length T-type method. • The longitudinal thermal conductivity reaches up to 335.6±27.4 W m−1 K−1 at 300 K. • The thermal conductivity keeps decreasing with temperature rising from 300 K to 380 K. Expanded graphite (EG) is a well-known carbon derivative and widely used as the thermally conductive enhancer for thermal management composites. However, the investigation on thermal conductivity measurement of an individual EG particle is still unexploited, which prevents the exploration of the coupling mechanism between EG and matrices and further measures for thermal conductivity enhancement. Herein, using a variable-length T-type method, we measure the thermal conductivity of an individual expanded graphite ribbon (EGR) obtained by mechanically compressing a separate EG particle. The EGR has a micrometer-sized thickness and a millimeter-sized length. By changing the sample length while maintaining the contact junction, we simultaneously obtained the thermal conductivity of the EGR and the thermal contact resistance between the sample and the probe. The longitudinal thermal conductivity of the EGR reaches up to 335.6±27.4 W m−1 K−1 at room temperature and decreases to 254.8±20.8 W m−1 K−1 as the temperature rises from 300 K to 380 K. With a higher thermal conductivity than most graphene paper products and some carbon fibers, this low-cost nanocarbon-based material exhibits a great advantage in the development of thermally conductive composites, and the presented accurate thermal conductivity provides indispensable data for the rational design of composites. [Display omitted] [ABSTRACT FROM AUTHOR]

C-F bond cleavage by transient phosphorus(III)-based dications [RP(C(PPh3)2)]2+ (4a2+, R = Ph; 4b2+, R = 4-F-Ph) is reported. These dications were generated by reaction of the corresponding monocationic precursors with excess Na[BAr4Cl]. Evidence for the existence of transient dicationic species was obtained by trapping the dication 4a2+ with PMe3. According to theoretical analysis, the low-lying lowest unoccupied molecular orbitals of these species were responsible for the observed activation of C-F bonds. [ABSTRACT FROM AUTHOR]

The number of minimally invasive surgeries, such as video‐assisted thoracoscopic surgery and robot‐assisted thoracoscopic surgery, has increased enormously in recent years. More and more relevant studies report that anatomic pulmonary segmentectomy has the same effect as traditional lobectomy in the surgical treatment of early stage non‐small cell lung cancer (diameter less than 2.0 cm). Segmentectomy requires sufficient knowledge of the location of the pulmonary nodules, as well as the anatomy of the target segments, blood vessels, and bronchi. With the rapid development of imaging technology and three‐dimensional technology, three‐dimensional reconstruction has been widely used in the medical field. It can effectively assess the vascular branching patterns, discover the anatomic variations of the blood vessels and bronchi, determine the location of the lesion, and clarify the division of the segments. Therefore, it is helpful for preoperative positioning, surgical planning, preoperative simulation and intraoperative navigation, and provides a reference for formulating an individualized surgical plan. It therefore plays a positive role in anatomic pulmonary segmentectomy. This study reviews the progress made in three‐dimensional computed tomography reconstruction in anatomic pulmonary segmentectomy. [ABSTRACT FROM AUTHOR]

• Estimate inter-diffusion coefficients using compressed sensing method. • Excellent recovery of both inter-diffusivity and the composition-distance curve. • Less data than conventional methods based on least-square. • No preference on the locations of samples as long as in the diffused zones. • May modify the "pre-selected" order of the polynomial expression of inter-diffusivity as a function of compositions. Composition-dependent inter-diffusion coefficients are key parameters in many physical processes. Due to the under-determinedness of the governing diffusion equations, numerical methods either impose strict physical conditions on the samples or require a computationally onerous amount of data. To address such problems, we propose a novel inverse framework to recover the diffusion coefficients using a compressed sensing method, which in principle can be extended to alloy systems with arbitrary number of species. Comparing to conventional methods, the new approach does not impose any priori assumptions on the functional relationship between diffusion coefficients and concentrations, nor any preference on the locations of the samples, as long as it is in the diffused zone. It also requires much less data compared to least-squares approaches. Through a few numerical examples of ternary and quandary systems, we demonstrate the accuracy and robustness of the new method. [ABSTRACT FROM AUTHOR]

Bidirectional relativistic proper motions of radio components of nearby extragalactic sources give a strong constraint on the determination of the Hubble constant H[sub 0]. Under the assumption that the real velocity of radio components of extragalactic sources is not less than that of Galactic sources, the value of H[sub 0] can be estimated at a high level of accuracy. The assumption is reasonable due to the general belief that the activity in the core of galaxies must be more powerful than that of stars. This method is simple and with only one uncertainty — the real velocity of components. This uncertainty is related to the value of the real velocity of components of Galactic sources and the latter is always well-determined (note that the determination is independent of H[sub 0] and the distance of Galactic sources can be directly measured at a rather high level of accuracy). Hopefully the method will play an important role in future research to fix the value of H[sub 0]. With the data of the three sources available so far and the assumption that the real velocity of components of at least one of the sources is not less than a known velocity of components of a Galactic source, the constant is estimated to be within 27.08 kms[sup -1]Mpc[sup -1] < H[sub 0]≤ 53.15 kms[sup -1]Mpc[sup -1] with this method. [ABSTRACT FROM AUTHOR]

Developing from the photochromic metallacycles to the "turn‐on" photo‐switchable fluorescent metallacycles. [ABSTRACT FROM AUTHOR]

• A new gear RUL prediction model based on ON-LSTM is proposed. • The physical explanation of ON-LSTM is firstly achieved. • The frequency center index is found to be suitable for the gear health index. • This method has better long-term prediction ability than other traditional methods. • This method can implement RUL prediction in the case of small samples. Gear failure may affect the operation of mechanical equipment, and even cause the catastrophic break of machine and even casualties. Thus, the remaining useful life (RUL) estimation of the gear has important significance. This paper proposes a gear RUL prediction model based on ordered neurons long short-term memory (ON-LSTM) networks. The proposed methodology consists of two parts: firstly, extract the health index by computing frequency-domain features of raw signals; secondly, the ON-LSTM network model is constructed for generating the target output of the RUL prediction. Unlike the traditional LSTM neural network, the developed model integrating tree structures into LSTM to use the sequential information between neurons, so it has enhanced predictive ability. In comparative experiments, the Scores of ON-LSTM, LSTM, GRU, DLSTM and DNN are 0.398, 0.129, 0.07, 0.029 and 0.102, respectively; and ON-LSTM successfully fulfils twenty-three tasks while LSTM just fulfils five tasks in long-term prediction. Moreover, ON-LSTN only requires about 400 iterations for convergence, which is much faster than other RNNs. Experimental results show that ON-LSTM network achieved the best accuracy of short-term and long-term prediction, and it has the best robustness and convergence speed. And it can be effectively applied to the RUL prediction of gears. [ABSTRACT FROM AUTHOR]

• A multiple-degree-of-freedom dynamic model for high-speed bearing is constructed. • The influence of the local defect on cage and rolling element is first considered. • The dynamic responses under different working conditions and defects are analyzed. • The experiments on aero-engine spindle bearings are applied to validate the model. It is well known that the dynamic response of the rolling bearing would change especially in the acceleration vibration signal when the defects occur. To accurately simulate the dynamic response of a high-speed rolling bearing with a localized surface defect, we propose a new dynamic model for the faulty rolling bearing. The proposed model considers not only the high-speed effect of the rolling element, such as centrifugal force and gyroscopic moment, but also the degrees of freedom (DOFs) of all movable components, including five-DOF inner raceway, three-DOF balls and three-DOF the cage. Then the fourth order Runge-Kutta algorithm is used to solve the nonlinear differential equations of the model for obtaining the dynamic response of the bearing. Under different radial forces, rotational speeds and defect sizes, the acceleration vibration response of inner raceway and the motion of cage considering the effect of the localized surface defect are respectively analyzed. Finally, the correctness and effectiveness of the proposed model are proved by the measured signals of the faulty aero-engine spindle bearings. [ABSTRACT FROM AUTHOR]

A delayed crosslinked polymer gel was developed for in-depth water control in mature oilfields. The thermal gelation behavior of nonionic polyacrylamide (NPAM) and PEI was investigated, and sodium citrate (NaCit) was selected as a new retarder to prolong the gelation time. The gelation performance of NPAM/PEI gel system can be adjusted by varying NPAM or PEI concentration, and a quadratic model is developed by statistical analysis, which predicts the gelation time of NPAM/PEI gel system. The obtained model shows high significance and good reliability, as suggested by the F-ratio of 175.16 and high adjusted R-square value (0.9732). The addition of NaCit exhibits a good delayed gelation effect on the NPAM/PEI gel system, better than that of NaCl. The decrease of the initial pH value of the gelling solution leads to the weaker gel viscosity and longer gelation time due to the protonation of amine groups on the PEI chains. Increasing temperature results in higher gel viscosity but shorter gelation time. The gel system in the presence of NaCit exhibits good compatibility with injection and formation water. A dense three-dimensional structure was observed in matured NPAM/PEI/NaCit gel, and it could keep stable below 160 °C. The gel system could effectively reduce the permeability (>95%) and restricted the flow of water after matured in natural cores. [ABSTRACT FROM AUTHOR]

Cleaning up spilled crude oil and recycling oily wastewater are global challenge. For the first time, we develop a simple approach to fabricate solar-driven superhydrophobic/oleophilic polybenzoxazine/reduced graphene oxide wrapped-cellulose sponge (PBZRGOS) for highly efficiency oil/water separation and rapidly crude oil cleaning up from water. Polybenzoxazine (PBZ) is introduced into the cellulose sponge as a binder to provide low surface energy. Reduced graphene oxide (RGO) is anchored tightly on the sponge skeleton with the aid of PBZ for fabricating a thermal conductive path. The resultant PBZRGOS with 5% content of RGO (PBZRGOS5) exhibited robust mechanical stability after 100th compression process and maintained ultrahigh oil/water fluxes (up to 107428 Lm-2 h−1 bar−1) under 0.10 bar as well as high oil/water separation efficiency (99.1%) after 10 cycles, which is superior to other reported modified sponges. Moreover, the light-heat conversion capacity of PBZRGOS driven by solar energy obviously reduce the viscosity of crude oil, speeding up crude oil-diffusion coefficient, and thus achieve the saturated adsorption capacity up to 61.1 g/g with one sun, which is 15.7 times higher than that of the PBZRGOS without sunlight. Therefore, it is expected that this self-heating and superhydrophobic cellulose sponge can be utilized as a competitive functional sponge for cleaning up spilled crude-oil in the large area water body. A self-heating polybenzoxazine/reduced graphene oxide wrapped-cellulose sponge via the light-heat conversion effect can reduce the viscosity of crude oil for achieving crude oil cleanup. Image 1 [ABSTRACT FROM AUTHOR]

To accurately and quantitatively detect the gear pitting of different levels on the actual site, this paper studies a new vision measurement approach based on a tunable vision detection platform and the mask region-based convolutional neural network (Mask R-CNN). The shooting angle can be properly set according to the specification of the target gear. With the obtained sample set of 1500 gear pitting images, an optimized deep Mask R-CNN was designed for the quantitative measurement of gear pitting. The effective tooth surface and pitting was firstly and simultaneously recognized, then they were segmented to calculate the pitting area ratio. Considering three situations of multi-level pitting, multi-illumination, and multi-angle, several indexes were used to evaluate detection and segmentation results of deep Mask R-CNN. Experimental results show that the proposed method has higher measurement accuracy than the traditional method based on image processing, thus it has significant practical potential. [ABSTRACT FROM AUTHOR]

With the introduction of ChatGPT, the public's perception of AI-generated content has begun to reshape. Artificial intelligence has significantly reduced the barrier to entry for non-professionals in creative endeavors, enhancing the efficiency of content creation. Recent advancements have seen significant improvements in the quality of symbolic music generation, which is enabled by the use of modern generative algorithms to extract patterns implicit in a piece of music based on rule constraints or a musical corpus. Nevertheless, existing literature reviews tend to present a conventional and conservative perspective on future development trajectories, with a notable absence of thorough benchmarking of generative models. This paper provides a survey and analysis of recent intelligent music generation techniques, outlining their respective characteristics and discussing existing methods for evaluation. Additionally, the paper compares the different characteristics of music generation techniques in the East and West as well as analysing the field's development prospects. [ABSTRACT FROM AUTHOR]

To address the challenge of poor fracture toughness of lithium disilicate glass-ceramics, which hinders their application as posterior single crowns and three-unit fixed bridges, the concept of fiber toughening was employed. In this study, Li 2 Si 2 O 5 fibers were successfully prepared through an electrospinning technology combined with sol-gel followed by a heat treatment. The fibers could be further densified by adding SiO 2 nano-powder to partially replace TEOS as a silicon source and the possible mechanism was put forward. By using the fibers as the reinforcement phase, the uniform fiber-toughened Li 2 Si 2 O 5 glass-ceramic composites were successfully produced by hot pressing sintering. These composites exhibited significant enhancements in mechanical properties, including a flexural strength of 315 ± 10 MPa, fracture toughness of 4.57 ± 0.35 MPa m1/2, and Vickers hardness of 5.61 ± 0.28 GPa, respectively. Notably, the highest fracture toughness of the composite increased by 41 % compared to the samples without fiber reinforcement, which was attributed to the toughening mechanisms including crack deflection, fiber bridging, and fiber pull-out. The results demonstrated the advantages of Li 2 Si 2 O 5 fibers in toughening glass-ceramic materials, thereby expanding the application areas of this material. [ABSTRACT FROM AUTHOR]

Current osteoarthritis (OA) diagnosis relies on radiographic abnormalities found in later stages of the disease, posing a challenge to the treatment efficacy. Therefore, earlier detection of OA is essential for improving therapeutic outcomes. The aim of this study was to investigate the feasibility of shear wave ultrasound elastography (SWUE) to detect changes in cartilage mechanical properties under OA conditions ex-vivo. Bovine osteochondral units were harvested from femoral condyles and subjected to either trypsin degradation, cartilage surface roughness defect using varying degrees of sandpaper, or subchondral bone degeneration using formic acid (FA) injection. Shear waves were generated using a mechanical shaker, while a high-frequency ultrasound system operating at 18 MHz was employed to detect wave propagation along the samples. The elasticity of cartilage was estimated by the shear wave speed (SWS) through the auto-correlation method. Our results show that the estimated SWS of cartilage after 24, 48, and 72 hours of trypsin incubation significantly decreased by 37%, 43%, and 59%, respectively, compared to the control group. Surface roughness treatment using 150-grit sandpaper significantly decreased the SWS by 35% compared to the control. Samples treated with 7% FA showed a significant increase in SWS by 62%, 89%, and 53% compared to control, 1% FA, and 3% FA, respectively. Our findings demonstrate the feasibility of SWUE to differentiate the elastic properties of cartilage under different OA conditions. This study presents the potential of a noninvasive, nonionizing tool for early detection of OA, representing a significant step toward its clinical implementation. Highlights: • Shear wave ultrasound elastography noninvasively measure the elastic properties of soft tissue. • Increasing cartilage surface roughness and enzyme degradation results in slower shear wave speeds. • Subchondral bone degradation increases shear wave speed in cartilage. • Shear wave ultrasound elastography is a novel method for early osteoarthritis diagnosis. [ABSTRACT FROM AUTHOR]

For decades, great strides have been made in the field of immunometabolism. A plethora of evidence ranging from basic mechanisms to clinical transformation has gradually embarked on immunometabolism to the center stage of innate and adaptive immunomodulation. Given this, we focus on changes in immunometabolism, a converging series of biochemical events that alters immune cell function, propose the immune roles played by diversified metabolic derivatives and enzymes, emphasize the key metabolism-related checkpoints in distinct immune cell types, and discuss the ongoing and upcoming realities of clinical treatment. It is expected that future research will reduce the current limitations of immunotherapy and provide a positive hand in immune responses to exert a broader therapeutic role. Highlights: 1. Attempting to delineate the complex and multidimensional interplays between metabolites (or metabolic enzymes) and predominant immune cell populations. 2. Metabolic checkpoints of immune cells are described and the contribution of these metabolic targets to determine the metabolic adaptations of distinct immune cells in specific tissue environments is emphasized. 3. Proposed cancer-immunometabolism subcycle, enriching the theoretical foundation of the cancer-immunology field. 4. Metabolism-induced disturbances in the acid-base balance of the tumor microenvironment have non-redundant effects on immunotherapy. 5. Pending challenges and clinical concerns in metabolic insights were addressed. [ABSTRACT FROM AUTHOR]

The fabrication of a multimodal phototheranostic platform on the basis of single‐component theranostic agent to afford both imaging and therapy simultaneously, is attractive yet full of challenges. The emergence of aggregation‐induced emission luminogens (AIEgens), particularly those emit fluorescence in the second near‐infrared window (NIR‐II), provides a powerful tool for cancer treatment by virtue of adjustable pathway for radiative/non‐radiative energy consumption, deeper penetration depth and aggregation‐enhanced theranostic performance. Although bulky thiophene π‐bridges such as ortho‐alkylated thiophene, 3,4‐ethoxylene dioxythiophene and benzo[c]thiophene are commonly adopted to construct NIR‐II AIEgens, the subtle differentiation on their theranostic behaviours has yet to be comprehensively investigated. In this work, systematical investigations discovered that AIEgen BT‐NS bearing benzo[c]thiophene possesses acceptable NIR‐II fluorescence emission intensity, efficient reactive oxygen species generation, and high photothermal conversion efficiency. Eventually, by using of BT‐NS nanoparticles, unprecedented performance on NIR‐II fluorescence/photoacoustic/photothermal imaging‐guided synergistic photodynamic/photothermal elimination of tumors was demonstrated. This study thus offers useful insights into developing versatile phototheranostic systems for clinical trials. [ABSTRACT FROM AUTHOR]

The fabrication of a multimodal phototheranostic platform on the basis of single‐component theranostic agent to afford both imaging and therapy simultaneously, is attractive yet full of challenges. The emergence of aggregation‐induced emission luminogens (AIEgens), particularly those emit fluorescence in the second near‐infrared window (NIR‐II), provides a powerful tool for cancer treatment by virtue of adjustable pathway for radiative/non‐radiative energy consumption, deeper penetration depth and aggregation‐enhanced theranostic performance. Although bulky thiophene π‐bridges such as ortho‐alkylated thiophene, 3,4‐ethoxylene dioxythiophene and benzo[c]thiophene are commonly adopted to construct NIR‐II AIEgens, the subtle differentiation on their theranostic behaviours has yet to be comprehensively investigated. In this work, systematical investigations discovered that AIEgen BT‐NS bearing benzo[c]thiophene possesses acceptable NIR‐II fluorescence emission intensity, efficient reactive oxygen species generation, and high photothermal conversion efficiency. Eventually, by using of BT‐NS nanoparticles, unprecedented performance on NIR‐II fluorescence/photoacoustic/photothermal imaging‐guided synergistic photodynamic/photothermal elimination of tumors was demonstrated. This study thus offers useful insights into developing versatile phototheranostic systems for clinical trials. [ABSTRACT FROM AUTHOR]

Enterovirus 71 (EV71) is a neurotropic enterovirus associated with hand, foot, and mouth disease (HFMD) fatalities. In this study, we investigated the impact of EV71 on plasmacytoid dendritic cells (pDCs) and CD4+ T cells. The results showed that pDCs were promptly activated, secreting interferon (IFN)-α and inducing CD4+ T cell proliferation and differentiation during early EV71 infection. This initiated adaptive immune responses and promoted proinflammatory cytokine production by CD4+ T cells. Over time, viral nucleic acids and proteins were synthesized in pDCs and CD4+ T cells. Concurrently, the cholinergic anti-inflammatory pathway (CAP) was activated, exhibiting an anti-inflammatory role. With constant viral stimulation, pDCs and CD4+ T cells showed reduced differentiation and cytokine secretion. Defects in pDCs were identified as a key factor in CD4+ T cell tolerance. CAP had a more significant regulatory effect on CD4+ T cells than on pDCs and was capable of inhibiting inflammation in these cells. [ABSTRACT FROM AUTHOR]

Object detection occupies a very important position in the fishing operation and autonomous navigation of underwater vehicles. At present, most deep-learning object detection approaches, such as R-CNN, SPPNet, R-FCN, etc., have two stages and are based on anchors. However, the previous methods generally have the problems of weak generalization ability and not high enough computational efficiency due to the generation of anchors. As a well-known one-stage anchor-free method, CenterNet can accelerate the inference speed by omitting the step of generating anchors, whereas it is difficult to extract sufficient global information because of the residual structure at the bottom layer, which leads to low detection precision for the overlapping targets. Dilation convolution makes the kernel obtain a larger reception field and access more information. Multi-branch structure can not only preserve the whole area information, but also efficiently separate foreground and background. By combining the dilation convolution and multi-branch structure, multi-branch dilation convolution is proposed and applied to the Hourglass backbone network in CenterNet, then an improved CenterNet named multi-branch dilation convolution CenterNet (MDC-CenterNet) is built, which has a stronger ability of object detection. The proposed method is successfully utilized for detection of underwater organisms including holothurian, scallop, echinus and starfish, and the comparison result shows that it outperforms the original CenterNet and the classical object detection network. Moreover, with the MS-COCO and PASCAL VOC datasets, a number of comparative experiments are performed for showing the advancement of our method compared to other best methods. [ABSTRACT FROM AUTHOR]

Neu1 is a sialidase enzyme that plays a crucial role in the regulation of glycosylation in a variety of cellular processes, including cellular signaling and inflammation. In recent years, numerous evidence has suggested that human NEU1 is also involved in the pathogenesis of various respiratory diseases, including lung infection, chronic obstructive pulmonary disease (COPD), asthma, and pulmonary fibrosis. This review paper aims to provide an overview of the current research on human NEU1 and respiratory diseases. [ABSTRACT FROM AUTHOR]

Alteration of HIF-1α expression levels under hypoxic conditions affects the sequence of its downstream target genes thereby producing different effects. In order to investigate whether the effect of hypoxic compound exercise (HE) on HIF-1α expression alters cardiac pumping function, myocardial structure, and exercise capacity, we developed a suitable model of hypoxic exercise using Drosophila, a model organism, and additionally investigated the effect of hypoxic compound exercise on nocturnal sleep and activity behavior. The results showed that hypoxic compound exercise at 6% oxygen concentration for five consecutive days, lasting 1 h per day, significantly improved the cardiac stress resistance of Drosophila. The hypoxic complex exercise promoted the whole-body HIF-1α expression in Drosophila, and improved the jumping ability, climbing ability, moving speed, and moving distance. The expression of HIF-1α in the heart was increased after hypoxic exercise, which made a closer arrangement of myofilaments, an increase in the diameter of cardiac tubules, and an increase in the pumping function of the heart. The hypoxic compound exercise improved the sleep quality of Drosophila by increasing its nocturnal sleep time, the number of deep sleeps, and decreasing its nocturnal awakenings and activities. Therefore, we conclude that hypoxic compound exercise promoted the expression of HIF-1α to enhance the exercise capacity and heart pumping function of Drosophila, and improved the quality of sleep. [ABSTRACT FROM AUTHOR]

For CFRP-strengthened steel structures, corrosion defects in steel are incredibly hazardous, but there is a lack of effective non-destructive testing methods. Based on the low-power vibrothermography (LVT) technique, this study proposes a quantitative detection framework for corrosion defects of CFRP-strengthened steel structures, including feature extraction algorithms for improving the defect detectability, and a feature enhancement method for reducing the quantification error. First, a finite element model is built to simulate the heat generation under ultrasonic excitation and to obtain the temperature distribution on the specimen surface. The processing results of the simulated thermal images show that feature extraction algorithms (FFT, PCA, and PLSR) effectively extract defect features. Subsequently, the LVT experimental setup was established to detect corrosion defects in CFRP-strengthened steel specimens. The experimental results demonstrate that the LVT technique can selectively heat corrosion defects, and processing results prove that the FFT and PLSR can further enhance the defect detectability. Finally, we propose a feature enhancement method based on gravitational calculation and double-threshold segmentation to reduces the quantification error. The quantitative evaluation relative errors of defects with diameters of 10 mm, 8 mm, and 6 mm are 5.26%, 5.26%, and 10.09%, respectively. [ABSTRACT FROM AUTHOR]

This study investigated whether mobile payment (MP) adopters in China extend their MP usage during their travel abroad, through the lens of continuity theory. The findings from in-depth interviews articulated six major concerns while using MP at home, namely perceived risks, costs, incompatibility, complexity, customer support, and social influence. Three major concerns for not using MP when travelling abroad include perceived security risk, costs, and incompatibility. Discontinuity of usage include past experiences and concerns about using MP in the home country, together with their negative evaluation of the MP service environment of the travel destinations. This study answers why some Chinese tourists abandon MP when they travel. Practical implications are offered to service providers to enhance users’ experiences. [ABSTRACT FROM AUTHOR]

African swine fever (ASF) is an infectious disease caused by ASF virus (ASFV), which is characterized by high infectivity, rapid onset of disease, and a high mortality rate. Outbreaks of ASFV have caused great economic losses to the global pig industry, and there is a need to develop safe and effective vaccines. In this study, two recombinant pseudorabies virus (PRV) strains, rGXGG-2016-ΔgI/ΔgE-EP364R and rGXGG-2016-ΔgI/ΔgE-B119L, expressing the EP364R and B119L protein, respectively, of ASFV, were constructed by homologous recombination technology. Western blotting and immunofluorescence analysis showed that these foreign proteins were expressed in cells infected with the recombinant strains. The strains showed good genetic stability and proliferative characteristics for 20 passages in BHK-21 cells. Both of these strains were immunogenic in mice, inducing the production of specific antibodies against the expressed ASFV proteins while providing protection against lethal challenge with PRV. Thus, the recombinant strains rGXGG-2016-ΔgI/ΔgE-EP364R and rGXGG-2016-ΔgI/ΔgE-B119L could be used as candidate vaccines for both ASFV and PRV. In addition, our study identifies two potential target genes for the development of safe and efficient ASFV vaccines, provides a reference for the construction of bivalent ASFV and PRV vaccines, and demonstrates the feasibility of developing a live ASFV vector vaccine. [ABSTRACT FROM AUTHOR]

• The coupled BTMS with PCMs and cold plates is designed for performance improvement. • Aerogel is used to replace the unmelted PCMs for weight reduction. • A strategy is developed to optimize the distribution of PCMs/Aerogel. • T max and Δ T are reduced by 1 K and 49 % respectively after the optimization. • The weight of PCMs/Aerogel is reduced by 45 % after the optimization. The thermal management system is critical for battery packs in electrical vehicles. Coupling the battery thermal management system (BTMS) with phase change materials (PCMs) and cold plates (CPs) has demonstrated good cooling performance. However, part of the PCMs inside the existing systems doesn't experience phase change, which contribute less to the cooling performance as the weight load increases. In this study, aerogel as the typical lightweight flame retardant materials (FRMs) is adopted to replace the un-melted PCMs to reduce the weight of the system. An optimization strategy for the distribution of PCMs/FRMs in the coupled BTMS is proposed to improve the cooling performance with the system's volume fixed. By locating PCMs on the high-temperature area, an optimized system can be obtained by taking just a few adjusting steps using the developed strategy. After the optimization, the maximum temperature and temperature difference inside the battery pack are reduced by1.0 K and 49% respectively, with the weight of the filling materials among battery cells decreasing by 45%. The proposed strategy shows great potential for efficient optimization of coupled BTMSs with phase change materials and cold plates, which can improve the cooling and lightweight performance of the system simultaneously. [ABSTRACT FROM AUTHOR]

[Display omitted] • sp2 / sp3 hybrid carbon material (DBGFs) is constructed by combining graphene and double benzene rings. • The interaction between graphene is enhanced due to hybridization of sp2 and existence of sp3. • The structure has good thermal stability (1557 K) and extremely high compression ratio modulus [176.84 GPa/(g·cm−3)]. • The mechanical properties of the new phases are significantly improved due to increasing ratio of sp3. Carbon materials with a diverse hybridization of states have been studied for many decades due to their excellent customizable properties. In current work, a proposed carbon-based framework material named Double Benzene rings Graphene-based Frameworks (DBGFs) was studied. DBGFs was designed from the hybridization of 2D graphene (sp2) and 0D double benzene-ring molecules (sp2). Its thermal stability and mechanical properties were investigated using molecular dynamic simulation and first-principles calculation. The results showed that DBGFs had a relatively higher thermal stability up to 1557 K due to the interlayer cohesive strength of the double benzene rings. Furthermore, the concentration of double benzene rings directly affects the tensile and shear modulus of DBGFs, highlighting their significance as functional components. Additionally, an intermediate and metastable phase (named as "douben") was observed under unidirectional compression of DBGFs-128 and other lower concentration of benzene rings, whereas the douben exhibits the slightly reduced thermal stability but improved mechanical properties in comparison to its original structure (DBGFs-128). In summary, these results of carbon materials show potential stratagem for designing high temperature and pressure resistant materials with hybridization of low dimensional materials in future. [ABSTRACT FROM AUTHOR]

A novel design of a fan-shaped antenna embedded in semicircle aperture is proposed and experimentally studied in this article. The proposed antenna is fed by a tapered coplanar waveguide (CPW) and has an ultrawide band owing to the coupling between the fan-shaped radiation unit and the ground. From experimental results, the measured impedance bandwidth of the antenna, determined by -10 dB return loss, can reach an operating bandwidth of 23.36 GHz (1.64–25 GHz), more than 175% with the center frequency operating at about 13.32 GHz. Good radiation patterns and gains covering the operating band have been observed. Details of the antenna design and experimental results are discussed in this article. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 2385–2387, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24655 [ABSTRACT FROM AUTHOR]

We report a specially designed type of temporal resolved x-ray spectroscopic diagnostic using a spherically bent quartz crystal for z-pinch plasmas. Registration of time-resolved spectra was accomplished by coupling fast plastic scintillator, an optical fiber array, an optical streak camera, and a charge coupled device as the recording medium of this diagnostic. The diagnostic has been tested in imploding wire array experiments on S-300 pulsed power facility. Time-resolved K-shell lines were successfully obtained for aluminum wire array implosion plasmas. [ABSTRACT FROM AUTHOR]

As an important component of industrial equipment, once gears have failures, they may cause serious catastrophes. Thus, the prediction of gear remaining life is of great significance. The health indicator of gears is first generated by fusing time-domain and frequency-domain features of gears vibration signals via the isometric mapping algorithm. Then a new type of long-short-term memory neural network with weight amplification (LSTMP-A) is proposed for accurately predicting gear remaining life. Compared with traditional LSTMs, LSTMP-A amplifies the input weights and the recurrent weights of the hidden layer to different degrees by the attention mechanism according to the contribution degree of the corresponding data, and a projection layer is added into the network. With LSTMP-A, we can predict the health characteristics of gears based on historical fusion features. With the monitoring data of a gear life cycle test, the comparative experiments show that the proposed gear remaining life prediction method has higher prediction accuracy than the conventional prediction methods. [ABSTRACT FROM AUTHOR]

• A new method for breaking the diffractive-imaging-based encryption is proposed. • The proposal is universal and has no additional restrictions during applications. • The proposal can still work even noise or occlusion occurred in the ciphertext. The only known approach that can break the diffractive-imaging-based encryption (DIBE) was proposed by Li and Shi in 2015. However, their approach works under the assumption that the phase distribution of the random phase masks (RPMs) is within [0, π]. In other words, it is no longer effective when such requirement is not fulfilled. In this paper, we propose a universal method, referred to as learning-based chosen-plaintext attack (L-CPA), to break DIBE. The L-CPA enables one to recover the plaintext from the ciphertext by aid of a well-trained artificial neural network (ANN), regardless of the phase distribution of the RPMs. Furthermore, the proposal can be accomplished with no need of knowing the details of the optical arrangement of DIBE. To our best knowledge, this is the first paper that reveals the absolute insecurity of DIBE against CPA. Numerical simulations are presented to demonstrate the effectiveness and feasibility of the proposal. [ABSTRACT FROM AUTHOR]

• A new dynamic model of faulty high-speed angular contact ball bearings is set up. • A B-spline fitting excitation function is used to represent the fault excitation. • The dynamic responses under different fault sizes and speeds are compared. • Experiment on high-speed bearings was performed to verify the proposed model. Angular contact ball bearings (ACBBs) are widely used in rotary machines especially in high-speed rotating machines because of their excellent properties. However, the traditional dynamic model of a rolling bearing is mainly applied to simulate the dynamic response at low speed, and uses the simple displacement excitation function to characterize the fault, thus its accuracy will decrease under high speed condition. Aiming at the shortcomings of the traditional model, a new high-speed fault dynamic model of ACBB is proposed by considering the influences of centrifugal force, gyroscopic moment and time-varying contact angles on the rolling element under high-speed running and using a B-spline fitting displacement excitation method to represent the fault excitation. With this model, high-speed dynamic responses under different fault sizes and rotation speeds are calculated by the Runge–Kutta method and Newton– Raphson method. Then the corresponding time and frequency domain characteristics are analyzed. From the simulation results, it can be seen that all the simulated acceleration signals of ACBBs are more in line with the actual situation than the traditional model, especially for the shape of an impulse. Finally, the effectiveness and correctness of the proposed model are verified by the experiment on aero-engine spindle bearings. [ABSTRACT FROM AUTHOR]

• A M-band flexible wavelet transform with high frequency resolution is constructed. • The wavelet filter bank is designed by the frequency domain method. • The fast numeric implementation algorithm of the proposed transform is presented. • This method can be well applied to diagnose the faults of planetary gearboxes. The fault diagnosis of planetary gear transmission systems is crucial for the safety of machineries and equipment. To identify the underlying fault features in measured signals, a novel M-band flexible wavelet transform is constructed. This transform provides a denser sampling of the time–frequency plane and preserves tunable filter parameters and dilation factors. A perfect reconstruction condition of the proposed transform is established, and its corresponding wavelet filter bank is designed to satisfy the perfect reconstruction condition. A numerical implementation algorithm of M-band flexible wavelet transform is investigated using a multirate filter bank and fast Fourier transform. Denoising the simulation signals demonstrates that the proposed transform exhibits better performance than analytic flexible wavelet transform, orthogonal wavelet transform, and biorthogonal wavelet transform. A new fault diagnosis method for planetary gear transmission systems is proposed on the basis of M-band flexible wavelet transform and spectral negentropy. Experimental and comparative results show that the proposed method can be more effectively and accurately applied to the fault diagnosis of planetary gear transmission systems compared with typical fault diagnosis methods based on analytic flexible wavelet transform, Morlet wavelet transform, and infograms. [ABSTRACT FROM AUTHOR]

Scaffold design plays an essential role in tissue engineering of articular cartilage by providing the appropriate mechanical and biological environment for chondrocytes to proliferate and function. Optimization of scaffold design to generate tissue-engineered cartilage has traditionally been conducted using in-vitro and in-vivo models. Recent advances in computational analysis allow us to significantly decrease the time and cost of scaffold optimization using finite element analysis (FEA). FEA is an in-silico analysis technique that allows for scaffold design optimization by predicting mechanical responses of cells and scaffolds under applied loads. Finite element analyses can potentially mimic the morphology of cartilage using mesh elements (tetrahedral, hexahedral), material properties (elastic, hyperelastic, poroelastic, composite), physiological loads by applying loading conditions (static, dynamic), and constitutive stress–strain equations (linear, porous–elastic, biphasic). Furthermore, FEA can be applied to the study of the effects of dynamic loading, material properties cell differentiation, cell activity, scaffold structure optimization, and interstitial fluid flow, in isolated or combined multi-scale models. This review covers recent studies and trends in the use of FEA for cartilage tissue engineering and scaffold design. [ABSTRACT FROM AUTHOR]