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The effects of annealing temperature on the microstructure, mechanical properties, and tribological properties of TiAlSiCN coatings with C contents of 9.24 at.% and 19.45 at.% are systematically investigated. The results show that all coatings maintain cubic structures with strongly preferential orientation of (200) planes, and the microstructure transforms from amorphous embedded in (Ti, Al)(C, N) nanocrystalline to amorphous encapsulated nanocrystalline with increasing C content. Elevating annealing temperature to 800 °C leads to a continuous decline in hardness, whereas the elastic strain resistance H/E increases first and then decreases. Release of H 2 formed by the breaking of the C–H bonds at 400 °C induces a local stress transformation from compressive to tensile. The toughness and hardness decreases dramatically at 600 °C by conversion of sp3 to sp2. The wear mechanisms of the coating against Si 3 N 4 counterballs are adhesive and oxidative wear. The coefficient of friction (COF) and wear rate initially decrease followed by an increase. The coatings with a-C structure exhibit lower COF and the wear process is smoother, but showing higher wear rate. Thus, the annealed TiAlSiCN coatings with preferred C content could improve the mechanical and tribological properties. [ABSTRACT FROM AUTHOR]

This study conducted experiments to investigate the impact of bottom obstacles, specifically broad-crest weir-type and cylindrical obstacles, on the flow within a sewer pipe. It was observed that these two types of obstacles, when possessing the same cross-sectional area and length, exhibited nearly equivalent hydraulic responses for both supercritical and subcritical flows. The obstacle height was found to be the primary factor responsible for choking and the transition between different flow regimes. The results of the one-dimensional analysis show that the threshold value of obstacle height depends on the approaching flow conditions, including the Froude number and the filling ratio that is defined as the flow depth to the pipe diameter. In the context of a partially blocked sewer, the relationships established by using the one-dimensional model between the size of the bottom obstacle and the inflow characteristics enable the identification of flow regimes, assessment of reduced hydraulic capacity, and evaluation of local energy loss. The findings of this study elucidate the hydraulic behavior of obstructed sewers, contributing to the development of more effective strategies for the identification of obstructions through monitoring data. [ABSTRACT FROM AUTHOR]

The objective of this paper is to investigate the complex three-dimensional vortex structures created by the interaction of gas jet with liquid crossflow. A high-speed camera technique is used to record the evolution patterns of the jet cavity. High-precision numerical methods with the Chorin projection method and volume of fluid method (VOF) are employed to understand the complex flow features associated with jet–freestream interaction. The results present that three distinct regions of the jet cavity could be observed, referred to as the transparent cavity region (TCR), the transition region (TR), and the foam cavity region (FCR). The interaction between the flow of gas jet and liquid crossflow creates multiscale vortex structures, including the counter-rotating vortex pair (CVP), the upper-deck counter-rotating vortex pair (up-CVP), the horseshoe vortices, the shear layer vortices, and the fine-scale vortices, respectively. The relationship between multiscale vortex structures and the pulsation of the gas-liquid interface is analyzed in detail by analyzing the spatial distribution of different vortex structures and the fluctuations of the gas-liquid interface. In addition, the effect of the gas entrainment coefficient on cavity flow patterns and vortex structures is compared and analyzed. • A high-precision numerical simulation method with the Chorin projection method and volume of fluid method (VOF) is established to capture all essential vortex structures for gas jet in liquid crossflow. • The multiscale vortex structures are observed for gas jet in liquid crossflow and the relationships between multiscale vortex structures and gas-liquid interface fluctuation are analyzed in detail. • The discrepancies of the vortex structures and the instability characteristic of the gas-liquid interface at different C Q are analyzed. [ABSTRACT FROM AUTHOR]

Sheet/cloud cavitation usually leads to a wide range of length scales in both turbulence and phase distribution from microbubbles to cavity advection. In the present work, the Eulerian–Lagrangian multiscale cavitation model with two-way coupling is utilized to simulate the cavitating flow around a (National Advisory Committee for Aeronautics) NACA66 hydrofoil at an incidence angle of 8° and a cavitation number of σ = 1.4. The model can simultaneously capture the large-scale cavities and the microscale bubbles. The cavitating flow features are in good agreement with the experimental observations containing not only the periodical formation, growth, detachment, and advection of large-scale cavities, but also thousands of microbubbles around the large-scale cavities. The results show that the overall evolution frequency in the flow is about 45 Hz. Meanwhile, the dynamic mode decomposition method is utilized to identify the large-scale coherent spatial and temporal features of the sheet/cloud cavitating flow, which indicates that complex vortices in various scales dominate the evolution of cavities in the corresponding scale, and the evolution frequency of large-scale vapor structure decreases with increasing the length scale of cavities. Under the effect of turbulence, the large-scale cavities break into microbubbles, causing the size and number of discrete bubbles to increase rapidly in the re-entrant jet and cloud shedding regions. Additionally, the bubble-size spectrum of the time-averaged distribution of a period in sheet/cloud cavitating flow has two size regimes. For larger bubbles, the bubble density is proportional to the bubble radius to the power of −10/3. The bubble size spectrum of smaller microbubbles exhibits a −4/3 power-law scaling. [ABSTRACT FROM AUTHOR]

This paper investigates the processes of droplet condensation and self-propelled jumping on microcolumn-structured superhydrophobic surfaces with various size parameters. Using a three-dimensional (3D) multiphase lattice Boltzmann method, a novel phenomenon of secondary coalescence jumping is identified, and the underlying mechanisms are analyzed in detail. The simulation results show that wettability has a significant influence on droplet jumping. As the hydrophobicity of the surface increases, the droplets tend to jump from the substrate. However, structure parameters, such as the microcolumn spacing and height, have non-monotonic effects on droplet jumping. The structure parameters determine whether droplet coalescence occurs under the bottom–bottom droplet coalescence mode or the bottom–top droplet coalescence mode. Bottom–bottom droplet coalescence is shown to promote droplet jumping. Based on the simulation results and kinetic analysis, the optimal spacing-to-width and height-to-width ratios of the microcolumns for droplet jumping are found to be approximately 0.6 and 1.0, respectively. We believe the results of this work will provide valuable guidance in the design of self-cleaning surfaces and enhancing heat transfer efficiency. [ABSTRACT FROM AUTHOR]

A physical model study was conducted on jet impingement in a plunging dropshaft with different drop heights of 3.38 and 1.88 m. Experimental observations show that an upward splash, annular flow, and downward bounced jet could be formed when the approaching jet hits the opposite shaft wall. The impinging pressure on the shaft wall was mainly dominated by the incoming flow velocity, and the mean pressure on the shaft wall can be reasonably well-predicted when considering the bounced flow. The pulsation of the impinging pressure on the shaft wall was significant, with the maximum pressure being approximately 1.4–3.8 times the mean value. The impinging pressure at the shaft bottom was primarily determined by the velocity at which the falling jet reached the pool. The mean value can be well estimated using the annular flow and bounced jet assumption. The pulsation intensity increased with an increase in drop height or flow rate, which could be alleviated by a plunging pool with a larger depth. However, for flows in dropshafts under study, the impinging pressure and the hydrostatic pressure of the cushion layer were within the same order of magnitude; thus, the increase of the pool depth leads to a reduction of the energy-dissipation rate. [ABSTRACT FROM AUTHOR]

In this paper, an improved moving horizon estimation (MHE) is proposed for the constrained linear system with bounded noises. To improve the computational efficiency of the numerical algorithms used in the MHE, a set-membership approach is employed to find a suitable search area. A tight set on decision variables is constructed based on the constrained zonotope technique. An optimization method for computing a tight zonotope enclosure of the constrained zonotope is proposed. Then the search area is further simplified into an optimal zonotope. Meanwhile, the cost function is constructed under the scenario of the worst-case noises statistical properties to improve the robustness of the MHE. For the incompletely specified probability distributions, the upper covariance matrix bounds are formulated as matrix inequalities. Finally, a numerical example illustrates the effectiveness of the algorithm. • An improved moving horizon estimation based on the setmembership approach. • The cost function of MHE is constructed under the scenario of the worst-case noises statistical properties. • A new re-scaling algorithm for the constrained zonotope is proposed. • The optimal zonotope enclosure of the constrained zonotope is provided. [ABSTRACT FROM AUTHOR]

Data-driven methods have been extensively utilized in establishing predictive models from historical data for process monitoring and prediction of quality variables. However, most data-driven approaches assume that training data and testing data come from steady-state operating regions and follow the same distribution, which may not be the case when it comes to complex industrial processes. To avoid these restrictive assumptions and account for practical implementation, a novel online transfer learning technique is proposed to dynamically learn cross-domain features based on the variational Bayesian inference in this work. Stemming from the probabilistic slow feature analysis, a transfer slow feature analysis (TSFA) technique is presented to transfer dynamic models learned from different source processes to enhance prediction performance in the target process. In particular, two weighting functions associated with transition and emission equations are introduced and updated dynamically to quantify the transferability from source domains to the target domain at each time instant. Instead of point estimation, a variational Bayesian inference scheme is designed to learn the parameters under probability distributions accounting for corresponding uncertainties. The effectiveness of the proposed technique with applications to soft sensor modelling is demonstrated by a simulation example, a public dataset and an industrial case study. [ABSTRACT FROM AUTHOR]

Atmospheric-plasma-sprayed yttrium–aluminium garnet coatings were exposed to Ar/O 2 /CF 4 plasma in a capacitively coupled plasma etching machine to induce fluoride-mediated corrosion and to elucidate the mechanism by which fluoride-containing plasma etched the coatings. In the first corrosion stage, the fully melted region, non-fused particles, and pore edges were etched; the etching products consisted of a series of aggregated and stacked fan-shaped particles, among which the non-fused particles exhibited the most severe etching. With prolonged etching, various coating surface regions gradually fused and smoothened, while the surface roughness decreased. Corrosion products Al 2 O 3 •AlF 3 , YOF, and YF 3 were also formed on the coating surface, and the etching product evolution looked like the fungus Ganoderma lucidum ; hence, the name 'fungal etching'. The study findings will further the development of ceramic coatings resistant to corrosion by halogen plasma for application to semi-conductor processing equipment. • APS YAG ceramic coatings were etched with Ar/CF 4 /O 2 plasma. • Etching products appeared on semi-molten particle surfaces/in pores/at FM zone edge. • Small fan-shaped etching traces evolved into large fungal-fruiting-body-type traces. • Etching products accumulated on coating surface were removed by ion bombardment. • Ion bombardment homogenised FM heights/integrated FM zones/smoothed coating surface. [ABSTRACT FROM AUTHOR]

In this article, an event-triggered distributed state estimation mechanism is proposed for general linear systems that comprise several subsystems. Two distributed moving horizon estimation (MHE) algorithms that can handle constraints on disturbances and noise are proposed. An event scheduler is exploited to govern the evaluation of the estimators and networked information exchange between the plant and the estimators, such that good estimates can be provided while both the usage of processors and networked communication frequency can be reduced. The estimation error provided by the event-triggered estimation mechanism is proven to be convergent and bounded. A numerical example and a chemical process example are used to verify the effectiveness and applicability of the proposed method. [ABSTRACT FROM AUTHOR]

The aging of sewer networks in old residential neighborhoods in China causes frequent problems with their integrity and functionality, such as sanitary sewer overflows and hydraulic overloading of wastewater treatment plants. In order to assess the performance of the sewer system in an old residential area in Ningbo, China, and to evaluate the effectiveness of the sewer system upgrade, the sewer system was continuously monitored for about 8 months. The quantity and quality of wastewater were comprehensively analyzed. The rainfall-derived inflow and infiltration (RDII) characterization was identified in the sewershed by using the R-value method and the triangle method. The R-values before and after the sewer upgrade were about 28% and 7%, respectively. The effects of the sewer upgrade were also quantified through comparing the concentration of pollutants before and after the program. The findings of this study will help to understand the performance of small-scale urban drainage systems, especially in old residential areas and/or in developing countries, and to provide guidance for future system upgrades. [ABSTRACT FROM AUTHOR]

[Display omitted] • The starches of three new varieties of corn cultivated by our team were investigated. • The structure and properties of 8 kinds of waxy, sweet waxy corn starch were studied. • The corn varieties that could replace waxy rice development products were identified. To explore the feasibility of substituting waxy rice with waxy or sweet-waxy corn, eight varieties of waxy and sweet-waxy corns were selected, including three self-cultivated varieties (Feng nuo 168, Feng nuo 211, and Feng nuo 10). Their starches were isolated and used as research objects, and commercially available waxy rice starch (CAWR) and waxy corn starch (CAWC) were used as controls. X-ray diffraction, scanning electron microscopy, differential scanning calorimetry, rapid viscosity analyzer, and rotational rheometer were used to analyze their physicochemical and structural characteristics. The morphologies of all corn starch granules were generally oval or round, with significant differences in particle size distributions. All ten starches exhibited a typical A-type crystal structure; however, their relative crystallinity varied from 20.08% to 31.43%. Chain length distribution analysis showed that the A/B ratio of Jing cai tian nuo 18 and Feng nuo 168 was similar to that of CAWR. Peak viscosities of corn starches were higher than that of CAWR, except for Feng nuo 10, while their setback values were lower than that of CAWR. Except for Feng nuo 10, the paste transparency of corn starches was higher than that of CAWR (10.77%), especially for Jing cai tian nuo 18 (up to 24%). In summary, Jing cai tian nuo 18 and Feng nuo 168 are promising candidates to replace CAWR in developing various rice-based products. [ABSTRACT FROM AUTHOR]

Multimodal sentiment analysis (MSA) is crucial as it integrates textual, visual, and audio information from videos to accurately identify human emotional states. This study proposes an innovative multimodal feature decoupling strategy that categorizes sentiment features into common and private features. The private features aim to accurately capture the uniqueness of each modality, thereby increasing feature diversity. In contrast, the common features seek to identify and capture commonalities among different modalities, thus reducing potential information loss during decoupling. To achieve this, we designed dedicated encoders and loss function constraints for both types of features. Additionally, to mitigate information redundancy and prevent key information loss during decoupled representation learning, we introduce a dual feature reconstruction mechanism comprising unimodal feature reconstruction (UFR) and multimodal feature reconstruction (MFR). These mechanisms preserve vital information from the decoupling process and mitigate the impact of redundant data. Our extensive experiments on three datasets demonstrate that our method achieves a significant margin of approximately 1%–3% in accuracy, illustrating that our approach outperforms existing advanced techniques significantly, resulting in noteworthy performance enhancements. [Display omitted] • We effectively disentangle private and common features across different modalities. • We propose a dual reconstruction mechanism for unimodal and multimodal feature. • Our model achieves significant enhancements in multimodal sentiment analysis. [ABSTRACT FROM AUTHOR]

In this paper, we propose a novel moving horizon estimation algorithm for discrete-time linear systems with a limited number of measurements. Motivated by the idea of the back-and-forth nudging algorithm, we design the back-and-forth nudging in time moving-horizon estimation method by deploying two moving horizon estimators that move backward and forward iteratively. Based on a finite number of measurements, the proposed algorithm can be used for moving-horizon state estimation with guaranteed convergence. By using the proposed method, we show that the norm of the state estimation error is upper bounded by a sequence that converges to its steady-state in finite-time (i.e., using a finite number of measurements), provided that suitable parameters are selected. The unbiasedness properties and comparison results with the conventional (forward-in-time) moving horizon estimation are discussed. The effectiveness of the proposed approach is validated through a numerical example. [ABSTRACT FROM AUTHOR]

In certain non-stationary processes, the non-stationary dynamics is caused by degradation or wearing of certain process components. Such dynamics can be characterized by a latent monotonic signal. Meanwhile, there also exist stationary dynamics characterizing the regular process variables. It hence becomes pertinent to distinguish these two sets of latent variables for the monitoring of the process from both the stationary and non-stationary aspects. In this regard, we propose a methodology to achieve such a goal by modeling the latent monotonic trend as a closed skew-normal random walk model. The other stationary relations are characterized by a state-space model with Gaussian noises. The problem is solved as a simultaneous state and parameter estimation problem using the expectation–maximization algorithm. As a result of the closed skew-normal random walk model for the monotonic trend, the state estimation problem becomes a skew-normal filtering and smoothing problem. The effectiveness of the proposed method is verified through a numerical simulation, and the algorithm is applied to solve a Hot Lime Softener fouling predictive monitoring problem. • Separation of the stationary and non-stationary sources of a deteriorating process. • The non-stationary source is modeled as a monotonic random walk model. • The monotonic latent variable is modeled as a closed skew-normal random walk model. • The proposed model leads to a simultaneous state and parameter estimation problem. • The problem is solved using the expectation-maximization (EM) algorithm. • Analytical derivation of the smoothing equations for a CSN state-space model. • Application of the proposed method on an industrial hot lime softener process. [ABSTRACT FROM AUTHOR]

In this article, an online estimator for faulty sensor signal is proposed for industrial processes described by nonlinear state-space models. The potential sensor fault is modeled as an unknown additive Gaussian signal, whose distribution is estimated together with the probability density function (pdf) of the state by using the variational Bayesian inference. To solve the problem that transition dynamics of faults are unavailable, a heuristic model with probabilistic features is discussed together with other commonly-used descriptions. For the computation issue caused by nonlinearities, a set of weighted particles is employed to estimate the pdf of state empirically, while the counterpart of the faulty signal is still calculated analytically. The effectiveness of the proposed algorithm is verified by a robot localization example and an experiment conducted on a flexible rotary joint. It shows that the proposed algorithm yields improvements over the existing algorithms, including the Bayesian estimator and the modified multiple-model-based method, and can satisfactorily estimate the magnitude of fault as well as its location in an online manner. [ABSTRACT FROM AUTHOR]

Slow feature analysis (SFA) is an unsupervised learning method that extracts the latent variables from a time series dataset based on the temporal slowness aspect. Neural networks, owing to their ability to model complex nonlinearities, can be used to extract slow features (SFs) from a dataset obtained from a complicated process. Siamese neural networks can be used for this purpose. Siamese neural networks have a provision of handling two samples at a time and this aspect helps in extracting SFs. For supervised learning applications, the extracted SFs should help predict the outputs. In this article, we present two approaches that extract SFs using Siamese neural networks. The output relevance aspect is brought into feature extraction as a regularization term in the objective function of the Siamese neural network. Such regularization improves the performance of the neural network model. The proposed approaches are implemented on three datasets to demonstrate their effectiveness. [ABSTRACT FROM AUTHOR]

The objective of this paper is to study flow-induced vibration in cavitating flow around a steel stainless hydrofoil with the experimental and dynamic mode decomposition (DMD) method. A synchronized measured system consisting of a high-speed camera, lift measurement, and laser Doppler vibrometer is used to observe the cavitation structures, survey the vibrations, and measure the force. The hydrodynamic force and vibration velocity fluctuate most sharply in the cloud cavitation stage among all the cavitation regimes due to the unsteady cloud cavity, corresponding to the largest square root of normal distribution in the cloud cavitation in the analysis of statistic nature. Cavity shedding frequency, system-related frequency, and trailing edge vortex shedding frequency are observed in the vibration velocity frequency spectrum for the whole range of cavitation numbers. Cavity frequency dominates the structure response in the cloud cavitation regime. Two primary shedding mechanisms, re-entrant jet, and shockwave mechanism are identified for the cloud cavitation. The vibration velocity induced by the re-entrant jet mechanism is lower amplitude and larger frequency, while that induced by the shockwave mechanism is higher amplitude and smaller frequency due to the intense collapse of cloud cavity and rapid collapse of the attached cavity. Two peak bands related to the re-entrant jet development frequency and small-scale cavity shedding frequency are identified for the shockwave mechanism with DMD method. [ABSTRACT FROM AUTHOR]

• Analyze the vortex structures of unsteady sheet/cloud cavitating flows with different vortex identification method. • The liutex method with the magnitude and rotation direction of vortex is applied to investigate the cavitation dynamics. • The relative parameter ε is adopted to investigate the effects of rotation and shear in cavitating flow. The objective of this paper is to investigate the physical interaction of the cavitation-vortex dynamics around a 3D Delft hydrofoil by large eddy simulations combined with the Zwart–Gerber–Belamri cavitation model. Transient sheet/cloud cavitating flows around the twisted hydrofoil involves the primary and secondary cavity shedding characterized by a U-shape structure, which is consistent with previous experimental data. Different vortex identification methods, namely, the ω criterion, Q criterion, Ω method and Liutex method, are applied to identify and analyze the vortex structure. The Liutex method is further utilized to visualize the detail of vortex structure in the primary and secondary cavity shedding process, especially for formation and development of the U- shape structure. For the primary cavity shedding process, the U- shape structure is the main feature of the shedding process. The primary U- shape vortex structure experiences distortion, and breaks into two parts at the vortex neck. Then, the front part develops into a O-shape structure, whereas the rear part still maintains a U- shape structure. Finally, both parts are dissipative completely in the form of U-shape structures. The shear plays a major role in the primary cavity shedding. For the secondary cavity shedding, U-shape, Ω-shape, O-shape, and hairpin vortexes are observed. The secondary U-shape vortex structure twists and deforms to form a hairpin vortex when the secondary cavity sheds completely, and finally dissipates with a smaller magnitude hairpin vortex. Rotation plays a major role in the secondary cavity shedding. [ABSTRACT FROM AUTHOR]

The COVID-19 pandemic compelled nonprofit human service organizations (NPHS) to rapidly adapt to heightened service demands while prioritizing the well-being of their staff and volunteers. Although digital platforms hold promise in facilitating NPHS adaptation, little is known about their impact during the crisis. How and through what pathways do digital platforms help NPHS adapt their service roles in times of crisis? Did digital platforms with different types of sponsorship vary in the way they affect NPHS's roles? Our study, based on 94 interviews in China, reveals that digital platforms assisted NPHS through three pathways: reducing transaction costs in stakeholder engagement, mitigating information asymmetry in targeting service recipients, and promoting shared responsibility for volunteer participation. Different sponsorship types influenced these pathways: government-sponsored platforms enhanced legitimacy, business-sponsored platforms leveraged private resources, and nonprofit-sponsored platforms bolstered citizen trust. This research informs scholars and practitioners on understanding how NPHS remained agile and innovative while facing extraordinary external challenges. To help nonprofit human service organizations (NPHS) adapt their service roles in synchronicity with the changing environment, we recommend that NPHS adopt suitable digital platforms for their collaborative network, client identification, and volunteer management during and after the public health crisis. NPHS need to use digital platforms to achieve a better online-offline synchronization in information and services. NPHS could use the online system of digital platforms to send online service information, facilitate offline service programs and motivate residents to take offline voluntary actions. For adopting nonprofit-sponsored digital platforms, NPHS should create collaborative networks of shops, banks, and volunteers within the community through issuing the credit system to earn citizens' trust, attract private resources and achieve legitimacy during and after the crisis. [ABSTRACT FROM AUTHOR]

Although VO 2 possesses an attractive theoretical specific capacity and a shear-type structure to resist lattice shear during repeated Zn2+ insertion/extraction, its poor electrical conductivity, easy self-aggregation, and inferior stability lead to sluggish reaction kinetics and unsatisfactory Zn2+ storage performance. In this work, we successfully constructed novel 2D VO 2 nanoplates embedded in a carbon matrix (VO 2 /carbon) utilizing a straightforward hydrothermal approach without using any template or calcination procedure. The thickness of the carbon layer can be tuned by modulating the experimental conditions. Impressively, the obtained 2D VO 2 /carbon with the optimal thickness of the carbon layer displayed satisfactory cyclic stability (63 % capacity maintained after 2500 cycles at 3 A g-1), excellent rate capability (202 mAh g-1 at 5 A g-1), and high specific capacity (501 mAh g-1 at 0.1 A g-1) as cathode material for aqueous zinc ion batteries (ZIBs), attributed to the desirable 2D nanoplate structure that offers effective pathways for Zn2+ diffusion together with sufficient electroactive sites for redox reactions and moderate carbon coating that buffers the volume changes in the course of repeated insertion/extraction of Zn2+ and accelerates charge/ion transfer. Furthermore, two assembled Zn//VO 2 /carbon coin cells successfully lit an orange light-emitting diode (LED) light for over 5 h, highlighting their potential as ideal candidates for low-cost, high-performance, environmentally friendly, and intrinsically safe energy storage devices. [ABSTRACT FROM AUTHOR]

Uncontrolled filling is often seen in storm sewers under wet weather conditions. This study develops a rigid-column model for rapid filling in a partially filled horizontal pipe with entrapped air. Numerical solutions compare very well with experimental measurements from earlier studies. Parametric analysis is conducted by nondimensionalizing the governing equations, and two typical scenarios are numerically investigated in detail: one with a fixed air pocket length and the other with a fixed air pocket volume under different tailwater depths. For the cases with a fixed air pocket length, the peak pressure becomes greater as the tailwater depth increases when the length ratio of the water column and the air pocket is large, whereas the trend is reversed when the length ratio is small. And the critical length ratio is system-dependent. In cases with a fixed air volume, the peak pressure is monotonically reduced with the increase in the tailwater depth. The proposed model can also be adapted for rapid filling with ventilation and surges in closed-conduit flows. [ABSTRACT FROM AUTHOR]

A momentum source function is constructed for wave generation based on linear wave theory. Based on Navier-Stokes equation and volume of fluid (VOF) method, a three-dimensional numerical wave tank (NWT) is established. Regular and irregular waves can be simulated by applying the momentum source function to NWT, and the expected wave characteristic parameters and wave spectrum are obtained. Furthermore, the load characteristics of two types of cylinders, fully piercing cylinder (FPC) and truncated cylinder (TC), are studied under regular wave field combined with boundary data immersed method (BDIM). Results show that the transverse force exerted on cylinders is dominated by inertial force. And because of the effects of the cylinder on wave profile and drag force, the maximum transverse force occurs soon after the wave node passes through the centerline of the cylinder. Compared with the FPC, the drag force has a greater influence on TC. • A momentum source function is constructed for the wave generation based on the linear wave theory. • The numerical methods are verified with the theoretical results. • The load characteristics of cylinders are numerically studied under the wave fields. [ABSTRACT FROM AUTHOR]

The effects of C doping content on the microstructure, mechanical and tribological properties of TiAlSiCN coatings prepared by ion plating are systematically investigated. The results show that the grain is refined with the C content increases to 17.22 at.%, and the (111) and (200) planes present competitive growth, the high C content promotes the preferred orientation of the (200) planes. The hardness of the coating shows a tendency to increase first and then decrease, the coating with C content of 8.15 at.% achieve the highest hardness, while the elastic strain resistance H/E value decreases monotonically. Moreover, it is found that the amorphous carbon (a-C) structure is precipitated with C content above 12.51 at.%. The wear mechanism of the coating against the Si 3 N 4 counterpart is adhesive, and the coefficient of friction (COF) of the coating decreases from 0.4 to 0.2. Thereinto, the reduction in COF is related to the Hertzian contact area as C content below 8.15 at.%. The COF further reduction is attributed to the generation of graphite lubricated structure. However, the wear rate shows first decrease and then increase. Therefore, the preferential C doping content can improve the mechanical and tribological properties of the coatings. • The research revealed that C content has significant effect on the microstructure and tribological properties of TiAlSiCN coating. High C content promotes the preferred orientation of the (200) planes. • The amorphous carbon (a-C) structure is precipitated with C content above 12.54 at.% • The lower COF is related to the Hertzian contact area decrease and the generation of graphite lubricated structure. [ABSTRACT FROM AUTHOR]

The interaction between the unsteady cavitating flow and hydrodynamic performance around a pitching Clark-Y hydrofoil is investigated experimentally and numerically. The experiments were conducted in the looped cavitation tunnel, and the cavitation patterns are documented by two high-speed digital cameras, and the moment of hydrofoil is measured by the moment sensor. The pitching hydrofoil is controlled from α+ = 10° to α+ = 15° firstly, and goes back to α− = 5° from α+ = 15°, then goes back to α+ = 10° from α− = 5° at Re = 4.4∗105. The upstream velocity U ∞ and the cavitation number σ is fixed at 6.3 m/s and 1.38, respectively. And the pitching rate is α ˙ = 40 ∘ / s , α ˙ ∗ = 0.086. The numerical investigations were performed by solving the incompressible UNRANS equations via the commercial code CFX using the Merkle cavitation model, the coupled k-ω SST turbulence model and γ - Re θ transition model. The predicted cavity patterns and moment coefficients agree well with the experimental results. The results showed there are two distinct cavitation patterns (Multi-scale cloud cavitation and Traveling sheet cavitation). For the Multi-scale cloud cavitation phase (α+ = 10°-α- = 10°), the re-entrant flow is the main factor on the stability of cavitating flow structures, which is responsible for different shedding patterns. According to the breaking position and re-entrant flow thickness, this stage is divided into three different patterns of the cavity development and shedding. For the Traveling sheet cavitation phase (α− = 10°-α+ = 10°), the shedding of cavity mainly results from the interaction of the re-entrant flow and the fluctuation of the gas liquid interface, thus leading to the irregular breaking points. The cavitating flow structure of different phases were further investigated using the LESs, which will be help to identify the dynamic behavior of flow structures effectively. • Two different cavitation patterns in the pitching process are investigated experimentally and numerically. • Cavitating flow stability is investigated for the multi-scale cloud cavitation phase with three cavity patterns. • Cavity shedding irregularity is further analyzed for the traveling sheet cavitation phase. [ABSTRACT FROM AUTHOR]

Rapid filling of a horizontal pipe with an entrapped air pocket has attracted significant attention as overpressurization induced by air compression may cause safety concerns. This study developed a linearized model for a rapidly filling horizontal pipe, by using a Jacobian linearization around the equilibrium point of the nonlinear system. The analytical expressions explicitly show the relationship between the characteristics of pressure oscillation and parameters including the driving head, the length of the water column, the length of the entrapped air pocket, the location of the equilibrium point, and the polytropic exponent. The oscillation frequency increases with the driving head whereas it decreases with the length of the air pocket. The obtained analytical solution compares well with the rigid-column model for a limited range, and it is improved by means of introducing power-law fitting for general cases. The linearization method also can be used in other cases, such as rapid filling in a horizontal pipe with the entrapped air pocket above an initial water layer or in slope/vertical pipes. [ABSTRACT FROM AUTHOR]

Background: Stem cell senescence has been proposed as one of the major drivers of aging, and MSC senescence contributes to aging-related diseases. Activation of mTORC1 pathway and heterochromatin organization have been characterized as two characteristics of senescent cells; however, whether mTORC1 pathway interacts with heterochromatin organization and contributes to MSC senescence remains unknown. In this study, we investigated the interaction between heterochromatin organization and mTORC1/p70S6K pathway in stress-induced MSC senescence. Methods: The stress-induced senescence models were established in human umbilical cord-derived MSCs by doxorubicin (Dox) or H2O2. Cellular senescence was evaluated by β-Gal activity, upregulation of cell cycle suppressor genes, and expression of SASP. Activation of heterochromatin organization and mTORC1 pathway was determined by Western blot and immunofluorescent staining. A D-galactose (D-Gal)-induced aging model was established in rats to evaluate the crosstalk between heterochromatin and mTORC1 pathway in vivo. Results: We found that heterochromatin organization was provoked at the early stage of Dox- or H2O2-induced senescence. Disruption of heterochromatin organization led to robust DNA damage response and exacerbated cellular senescence. Suppression of mTORC1/p70S6K pathway by either rapamycin or p70S6K knockdown promoted heterochromatin organization and ameliorated Dox- or H2O2-induced DNA damage and senescence. In contrast, direct activation of mTORC1 by MHY1485 impaired heterochromatin organization and aggravated stress-induced senescence. Moreover, concomitant activation of mTORC1 pathway and heterochromatin organization was found in D-galactose-induced osteoporosis model in rats. Rapamycin alleviated cellular senescence and promoted heterochromatin organization in BMSCs derived from D-galactose-treated rats. Conclusions: Altogether, our study indicates the existence of a complex interplay between the mTORC1/p70S6K pathway and the heterochromatin organization during stress-induced MSC senescence, with important implications for the understanding of aging as well as for its prevention and treatment. [ABSTRACT FROM AUTHOR]

Background: Skin cutaneous melanoma (SKCM) is one of the most malignant and aggressive cancers, causing about 72% of deaths in skin carcinoma. Although extensive study has explored the mechanism of recurrence and metastasis, the tumorigenesis of cutaneous melanoma remains unclear. Exploring the tumorigenesis mechanism may help identify prognostic biomarkers that could serve to guide cancer therapy. Method: Integrative bioinformatics analyses, including GEO database, TCGA database, DAVID, STRING, Metascape, GEPIA, cBioPortal, TRRUST, TIMER, TISIDB and DGIdb, were performed to unveil the hub genes participating in tumor progression and cancer-associated immunology of SKCM. Furthermore, immunohistochemistry (IHC) staining was performed to validate differential expression levels of hub genes between SKCM tissue and normal tissues from the First Affiliated Hospital of Soochow University cohort. Results: A total of 308 differentially expressed genes (DEGs) and 12 hub genes were found significantly differentially expressed between SKCM and normal skin tissues. Functional annotation indicated that inflammatory response, immune response was closely associated with SKCM tumorigenesis. KEGG pathways in hub genes include IL-10 signaling and chemokine receptors bind chemokine signaling. Five chemokines members (CXCL9, CXCL10, CXCL13, CCL4, CCL5) were associated with better overall survival and pathological stages. IHC results suggested that significantly elevated CXCL9, CXCL10, CXCL13, CCL4 and CCL5 proteins expressed in the SKCM than in the normal tissues. Moreover, our findings suggested that IRF7, RELA, NFKB1, IRF3 and IRF1 are key transcription factors for CCL4, CCL5, CXCL10. In addition, the expressions of CXCL9, CXCL10, CXCL13, CCL4 and CCL5 were positively correlated with infiltration of six immune cells (B cell, CD8+T cells, CD4+T cells, macrophages, neutrophils, dendritic cells) and 28 types of TILs. Among them, high levels of B cells, CD8+T cells, neutrophils and dendritic cells were significantly related to longer SKCM survival time. Conclusion: In summary, this study mainly identified five chemokine members (CXCL9, CXCL10, CXCL13, CCL4, CCL5) associated with SKCM tumorigenesis, progression, prognosis and immune infiltrations, which might help us evaluate several immune-related targets for cutaneous melanoma therapy. [ABSTRACT FROM AUTHOR]

The identification of the multiple model-based Hammerstein parameter varying systems is studied in this paper. The parameters of the considered systems vary as the systems perform on different operating conditions. For each local model, the input nonlinear output-error structure is introduced to describe the dynamical property. Allocating an exponential weighting function to each local model, the nonlinear dynamics of the global system is approximated by combining all local models. The variational Bayesian (VB) approach is adopted to find the solution to the problem of parameter estimation. For the parameter uncertainties, instead of the point estimation, the posterior distribution of each model parameters is obtained under the framework of the VB approach. Two numerical simulation examples and an experiment carried on a multitank system have been employed to demonstrate that the proposed approach can work effectively. [ABSTRACT FROM AUTHOR]

In distributed control systems, a local regulator does not have complete knowledge of the whole system. Therefore, some information is transmitted between local regulators through communication lines. The delays in communication lines are not negligible and they can make the closed‐loop system unstable or impose a limit on the achievable control performance. Due to the process and communication delays, controllers cannot reject all disturbances. Although there has been a plethora of literature available for assessing the control performance in the presence of process time delay, no similar study has been conducted for distributed control systems in the presence of communication delays. In order to address this problem, a new solution for performance assessment of distributed control systems, which takes communication delays into account, is proposed here. Further, the corresponding minimum variance controller is also derived under the distributed control framework with communication delays. [ABSTRACT FROM AUTHOR]

Research on coproduction of public services has grown significantly within the politics and public administration field during the last decade. The existing literature mostly assumes that coproduction requires additional costs from the public. This article explores whether and how digital technologies, which arguably have the ability to reframe public participation, might influence coproduction between the government and the public. A revised theoretical framework for coproduction in the era of digital governance is illustrated through a case study of the "Visit Once" administrative service reform in Zhejiang Province, China. This study reveals a new possibility for coproduction through digital technologies, in which citizens are involved in service improvement when using public services without costing them extra time or effort. Thus, the assumption of the necessity of additional costs from the public could be relaxed in the digital governance era. These findings also suggest that the significance of facilitative leadership in leading to coproduction can be moderated by digital technologies. [ABSTRACT FROM AUTHOR]

Slow feature analysis (SFA) is an approach that extracts features from a time series dataset in an unsupervised manner based on the temporal slowness principle. These slow features contain relevant information about the dynamics of the process and hence are useful for developing models. For supervised learning objectives, these slow features need to be relevant to the outputs. Partial least squares (PLS) is a method used to perform supervised feature extraction and build models. For time series datasets this approach cannot be used directly as it assumes each sample to be sequentially independent of each other. We propose an approach to perform feature extraction which combines the temporal slowness element of SFA and the output relevance element of PLS. The proposed approach extracts temporally slow features that are relevant to the outputs, which is an essential aspect of supervised learning. The proposed formulations can be solved using the existing PLS algorithms like NIPALS and SIMPLS with proposed modifications. The proposed methods are applied to three case studies: simulated, industrial and experimental case studies to demonstrate their efficacy. • A new approach for extracting output relevant slow features is proposed. • The proposed method combines the output relevance aspect of PLS and temporal slowness aspect of SFA. • Proposed formulations lead to solutions in terms of eigenvectors of certain matrices. • Modified versions of NIPALS and SIMPLS are proposed. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) porous materials have been proved to be meritorious for supercapacitors (SCs) due to unique properties of large surface area, superior intrinsic porosity and high electrical conductivity. In this work, we reported for the first synthesis of 2D porous Co 3 O 4 thin sheets assembled by ultrathin nanosheets via direct hydrothermal decomposition of aqueous solution of cobalt nitrate in the presence of benzoic acid (BA) without any template or surfactant. High specific capacity (497, 598.5 and 399 C g−1 at 1.0 A g−1) and remarkable cycling stability (9.8, 6.3 and 13.1% loss over 8000 cycles at 10.0 A g−1) were achieved in a three-electrode system for the Co 3 O 4 thin sheets at 200 °C for 6, 12 and 24 h with different specific surface area of 69.96, 142.15 and 42.07 m2 g−1, which can be attributed to the special structural feature of an open and porous surface layer and the synergistic effect of 2D and 3D structure that significantly facilitates fast electron transport, ion diffusion and intimate electrode/electrolyte contact. Furthermore, an assembled asymmetric supercapacitor (ASC, Co 3 O 4 thin sheets//activated carbon (AC)) can reach a working output potential difference of 0–1.6 V with a maximum energy density of 22.49 Wh·kg−1 at the power density of 800 W kg−1 with excellent cyclic stability (only 8.2% loss of its initial specific capacity value over 10000 cycles). The results show that our synthesis provides a new insight into the fabrication of 2D hierarchical porous Co 3 O 4 thin sheets; in addition, the as-synthesized Co 3 O 4 thin sheets have potential for various applications in SCs, electrochemical sensing, and lithium ion battery. Image 1 • Two-dimensional Co 3 O 4 thin sheets are prepared by a simple Benzoic acid-assisted hydrothermal method. • Nanoflake array-assembled porous sheets with high BET specific surface area. • The Co 3 O 4 thin sheets-based electrode shows an ultrahigh specific capacitance and superior cycling performance. • The assembled asymmetric supercapacitor exhibits a high energy density and high power density. [ABSTRACT FROM AUTHOR]

Aims: The aim of this study was to develop a new method for detecting anti-phospholipase A2 receptor-IgG4 to improve the sensitivity and specificity in the diagnosis of idiopathic membranous nephropathy (IMN). Methods: A highly sensitive quantitative assay was developed for the detection of serum anti-phospholipase A2 receptor-IgG4 with europium chelation by time-resolved fluoroimmunoassay (TRFIA), and a mouse anti-human IgG4 tracer was prepared using europium chelation for detection. The specificity and sensitivity of anti-phospholipase A2 receptor-IgG4 in the diagnosis of IMN were further assessed in patients with different kidney diseases. Results: The detection limit of anti-PLA2R-IgG4 was 0.69 ng/mL. The measurement range of anti-PLA2R-IgG4 TRFIA was 0.69–2,500 ng/mL. Mean serum anti-PLA2R-IgG4 was 21.27 ± 15.15 ng/mL in 45 healthy volunteers, 31.08 ± 18.17 ng/mL in 29 IgA nephropathy patients, 49.10 ± 34.32 ng/mL in 8 lupus nephropathy patients, and 10,324.11 ± 17,030.40 ng/mL in 30 IMN patients. The anti-PLA2R-IgG4 cutoff concentration was >161.2 ng/mL with the sensitivity of 90.0% and specificity of 100% in the diagnosis of IMN. However, the cutoff for other kidney diseases was lower than 161.2 ng/mL. Conclusion: The serum anti-phospholipase A2 receptor IgG4 detected with the method developed in this study has higher sensitivity and higher specificity than total IgG in the diagnosis of IMN. [ABSTRACT FROM AUTHOR]

Control Engineering Practice passed its 25 years mark (1993–2017). In commemoration with this milestone, we make an effort to acknowledge its contributors and recognize extraordinary contributions in terms of a set of bibliometric measures. Also the foci of research and application areas of the journal, as well as its link with other publication sources, are examined. The bibliometric analysis is performed for the articles published between 1993 and 2017; the citation statistics are taken for the period from 1994 to 2018. Publication and citation information are obtained from the Scopus database; the VOSviewer software is used for the keyword analysis. [ABSTRACT FROM AUTHOR]

Parameter estimation of Markov‐switching Hammerstein systems is presented in this study. The random switching mode is described by a hidden Markov model. An input non‐linear controlled autoregressive Hammerstein model is applied to describe the dynamic process of each local model. By applying the decomposition technique to the non‐linear mapping of the input signal, each local model is written as a linear‐in‐parameter form. The variational Bayesian approach is applied to identify the switched Markov Hammerstein models. Both the discrete‐valued switching mode state and the unknown parameters in each local model are estimated. Moreover, instead of the point estimation, posterior distributions of unknown parameters for each local model are obtained. Numerical simulation examples and a hybrid tank experiment are presented to verify the effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]

In this article, the governing equation of acoustic gravity waves is derived. Based on the governing equation, acoustic-gravity waves induced by a cylinder horizontally moving under water are investigated. Strong anisotropy phenomena are observed from the frequency spectra of the acoustic-gravity waves. According to the results, a set of line spectra, which are approximately two sets of continuous spectra, can be observed in the spectrum of the acoustic-gravity wave. A semi-analytic solution for the acoustic-gravity wave generated by the moving vortex pair in two-dimensional space is obtained with Green’s function to analyze the characteristic frequencies of the spectrum. The far-field solution of acoustic-gravity waves in three-dimensional space is asymptotically analyzed to explain phenomena observed from the frequency spectra. [ABSTRACT FROM AUTHOR]

The topology identification of sparse networks is crucial for network modeling in many fields. The variational Bayesian inference has been proved to be effective for solving this issue. However, since all the observed data are used to compute the posterior distributions of the global variables at each iteration of the classical variational inference, the computation complexity is too high to be suitable for large data sets, especially for large-scale networks, where more data is needed for the inference. In this paper, we derive an efficient algorithm to maximize a lower bound function in the Bayesian inference based on stochastic optimization, where only a part of data is used at each iteration. Compared with the traditional variational Bayesian inference approach, the proposed method can significantly decrease the computation so that it is more suitable for the network identification with large data sets. Several typical sparse networks are used to test the performance of the proposed method, and the results demonstrate its merits. [ABSTRACT FROM AUTHOR]

[Display omitted] • Mn atoms on the surface of nanozymes can scavenge reactive oxygen species. • The alleviation of inflammation promotes the recovery of blood–brain barrier. • Fluorescent nanozymes enable imaging-guided therapy of traumatic brain injury. Traumatic brain injury (TBI) often results in damage to the blood–brain barrier (BBB), leading to secondary effects such as neuroinflammation mediated by reactive oxygen species (ROS), which can increase the risk of long-term neurological dysfunction. Therefore, it is crucial to remove excessive ROS and monitor the status of BBB for timely clinical intervention. Here, we developed a fluorescent nanozyme by doping Mn atoms into PbS/CdS quantum dots (QDs) that emit in the near-infrared-II (NIR-IIb, 1500–1700 nm) region, enabling imaging-guided treatment of TBI. The QD-based nanozyme exhibited excellent antioxidant activity due to uniformly distributed Mn atoms on the surface, which effectively scavenged ROS and inhibited the release of pro-inflammatory factors, thus providing neuroprotective effects for TBI treatment. Additionally, the nanozyme demonstrated exceptional NIR-IIb fluorescence performance, allowing for dynamic monitoring of BBB status with high spatiotemporal resolution to guide precise TBI treatment. [ABSTRACT FROM AUTHOR]

The microstructure, mechanical and tribological properties of TiAlSiN coatings with various annealing temperature were studied. Results showed that the oxygen content of the coating raised with the annealing temperature in the range of room temperature to 800 °C, while the hardness decreased monotonically. However, the elastic strain resistance H/E value increased firstly and then decreased. The maximum H/E value of 0.105 was obtained at 400 °C. The deposited coating composed of c-TiN, c-AlN and c-(Ti, Al)N, and Si element mainly existed in the form of SiN x amorphous structure. The adhesive and oxidation erosion were the main wear mechanism against GCr15 steel balls. The coefficient of friction (COF) decreased gradually, but the wear rate increased firstly and then decreased. The minimum wear rate of 1.2 × 10−5mm3/(N·m) was obtained at 400 °C. In addition, oxides including Ti–O, Al–O and Si–O generated on the adhesives play a role of lubricant, which could reduce the shearing resistance and COF of the coating. Therefore, TiAlSiN coatings with optimal annealing temperature has excellent mechanical properties and tribological performance. The research revealed that the annealing temperature has significant effect on the microstructure and properties of TiAlSiN coating. • The TiO 2 oxides, which exists above the detection limit of XRD, are formed at 600 °C. • In addition, the shear resistance and contact area were reduced due to the adhesive Ti–O, Al–O and Si–O composition with low coefficient of friction and high hardness. [ABSTRACT FROM AUTHOR]

Abrupt variations are often observed in the datasets of chemical processes but they have not been well studied in the literature. This paper proposes a method of modeling and estimating systems characterized by abrupt (impulsive) changes. Abrupt changes may be due to multiple reasons such as disturbances, capacity change, etc. All these cases result in signals that appear to have sudden jumps. But mixed with these jumps are the other dynamic variations characterizing the regular dynamics of the process. For effective modeling, it is important to capture both the jumps and the regular dynamic variations. This paper proposes to model such behavior through a dynamic latent variable (LV) model. The resulting model has two types of LVs characterizing the abrupt and the regular variations. These two behaviors are modeled using a Cauchy and a Gaussian dynamic model respectively. The inference of the LVs and model parameters is done in the variational Bayesian framework. • Certain processes may be characterized by abrupt changes. • These occur due to disturbances or capacity changes. • A dynamic latent variable model is proposed that considers such abrupt changes. • The model contains two types of dynamic latent variables. • These evolve according to Cauchy and Gaussian distributions. • States and parameters are inferred using variational Bayesian inference framework. [ABSTRACT FROM AUTHOR]

Prediction is an essential part of predictive control and is widely applied in control engineering. In a distributed control system configuration, there are signal transmissions between local subsystems. Communication delays impose a limit on the achievable prediction performance. Even though there is a plethora of literatures available for multiple step ahead prediction under the centralised framework, they are traditional techniques that cannot be applied to the distributed framework due to the interactions between the different subsystems and communication delays that have not been taken into account. In this study, a technique for determining the distributed multiple step ahead prediction is proposed which is optimal in sense of the lowest total prediction error variance. The proposed approach is useful for designing optimal controllers or assessing the performance of the implemented control loop while the controller structure has the distributed framework. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract CoNi layered double hydroxides (LDH) and related monometallic hydroxides (Ni(OH) 2 and Co(OH) 2) were synthesized by a facile, simple and inexpensive method under mild condition (50 °C). The resulting products displayed a unique honeycomb-like nanoflakes array assembled two-dimensional (2D) thin sheets structure. Among them, CoNi-LDH thin sheets delivered higher specific capacity (394.5 C g−1 at 1 A g−1) with superior cyclic performance (92.3% capacity retention over 10,000 cycles) than Co/Ni monometallic hydroxides owing to the synergistic effect of cobalt and nickel. Afterward, hybrid supercapacitors (HSC) devices were fabricated using the as-obtained products (CoNi-LDH, Co(OH) 2 and Ni(OH) 2 thin sheets) and activated carbon (AC) as the positive and negative electrode, respectively. The operating voltage of the devices can be extended to 1.6 V. What’s more, the assembled CoNi-LDH HSC device exhibited a maximum energy density of 20.38 Wh kg−1 at the power density of 800 W kg−1. Consequently, these outstanding electrochemical performances of the CoNi-LDH thin sheet endow it with great potential to be implemented in HSCs or other energy storage systems. [ABSTRACT FROM AUTHOR]

Background: Vaccinia virus was widely used in the World Health Organization’s smallpox eradication campaign and is currently a promising vector for gene therapy owing to its unique characteristics. Vaccinia virus can selectively replicate and propagate productively in tumor cells, resulting in oncolysis. In addition, rapid viral particle production, wide host range, large genome size (approximately 200 kb), and safe handling render vaccinia virus a suitable vector for gene therapy.Materials and methods: Cancer vaccines and gene therapy are being studied in clinical trials and experiment researches. However, we put forward unique challenges of optimal selection of foreign genes, administration and modification of VACV, personalized medicine, and other existing problems, based on current researches and our own experiments. Conclusion: This review presents an overview of the vaccinia virus from its mechanisms to medical researches and clinical trials. We believe that the solution to these problems will contribute to understanding mechanisms of VACV and provide a theoretical basis for clinical treatment. [ABSTRACT FROM AUTHOR]

With increasing consumption of Vegetables planted in Plastic Greenhouses (VPGs) in China, phthalate exposure from VPGs represents an overlooked source of total daily exposure, since VPGs are not included in current phthalate exposure scenarios. For this reason, current exposure scenario modeling may underestimate the daily phthalate exposure in relation to adverse health impacts. Thus, in this paper we estimated the oral intake exposure to phthalates from VPGs by studying four provinces ranging from the north to the south in eastern China, based on published data. Exposures to di(2-ethylhexyl)-phthalate (DEHP) and dibutyl phthalate (DBP) were assessed for various population groups differentiated by age, sex, income, and region. Younger children experienced the highest exposure from VPG intake (mean 1.55 (0.19 and 6.20) (2.5th and 97.5th percentiles) μg/kg/body weight (bw)/day), followed by older children, teenagers, and adults (0.53 (0.06 and 1.80)). Exposures in urban populations were significantly higher than those in rural areas, and when examined by income, urban populations with low-income had the lowest exposures and the upper-middle income group was associated with the highest levels. Exposures in northeastern and southern provinces were higher than the levels in middle provinces due to regional disparities in dietary habits. Proportions of the mean oral intake exposures to DEHP and DBP from VPGs to the total daily exposure by modeling different exposure pathways and media were over 10% for all age groups. The DEHP and DBP exposure from VPG intake in China were found to be much higher than the levels in western countries. For example, exposures of older children to DBP and DEHP were respectively 17 and 4 times higher than European levels. The authors recommend policy interventions to protect populations from future risk of phthalate exposure. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • A new type of solid surface with amphiphilic micro-nanostructures is designed. • Condensation on the new designed surface is simulated by Lattice Boltzmann method. • The simulation results show that the new designed surface can promote condensation. Abstract The chemical properties and topography of solid surfaces exert a large effect on droplet condensation efficiency. Some scholars have devised a kind of amphiphilic microstructure with hydrophobic top and hydrophilic bottom, and their experiment results show that surfaces with this kind of amphiphilic microstructure can effectively reduce the size of condensed droplets and enhance condensation. In this paper, the Lattice Boltzmann method (LBM) is utilized to investigate this experiment numerically, and a corresponding conclusion is obtained. Further, nanostructures are added to this amphiphilic microstructure, and two kinds of amphiphilic micro-nanostructured surfaces were designed. The results by numerical studies demonstrate that the wettability of nanostructures on the top of amphiphilic micro-nanostructures are critical to condensation efficiency. Amphiphilic micro-nanostructured surfaces with hydrophilic nanostructures (amphiphilic micro-nanostructure I) possess better condensation efficiency than amphiphilic micro-structured surfaces and amphiphilic micro-nanostructured surfaces with hydrophobic nanostructures (amphiphilic micro-nanostructure II), which can significantly enhance droplet condensation. The findings of this paper provide guidance for the optimal design of surface structures to promote condensation. [ABSTRACT FROM AUTHOR]

The objective of this paper is to investigate the effects of air injection on the characteristics of two different unsteady sheet/cloud cavitation shedding mechanisms, namely re-entrant flow mechanism and bubbly shock propagation mechanism, in the convergent-divergent channel. Experiments were conducted in the 10° divergent section with a ventilation slit near the throat, using a simultaneous sampling technique to synchronize the transient cavity behaviors with wall-pressure signals. Results are presented at a Reynolds number 9.33 × 10 5 and Froude number 10.24 for (1) under re-entrant flow mechanism ( σ  = 0.81) characterized by the intermittent shedding of small-scale cavities, and (2) under bubbly shock propagation mechanism ( σ  = 0.70) characterized by periodic large-scale cavity cloud shedding, with three non-dimensional air injection volumetric flow rates, namely 0, 1.135 × 10 −3 and 2.270 × 10 −3 . The results show that air injection from the throat into the shear layer can significantly suppress cavitation induced unsteady pressure fluctuations. With the increasing of air flow rate, the size of the attached sheet cavity and the shedding cavity clusters grows larger, and the distance between the new attached sheet cavity and the shedding cavity cloud decreases, resulting in the cavitation region misty. The cavitation evolution tends to be stable, indicating the increase in the cavitation cycle, and the FFT analysis of the unsteady pressure fluctuations shows the decrease in dominant frequency. For the re-entrant flow mechanism condition, air injection rate at 1.135 × 10 −3 will cause the transition from small-scale cavity clusters shedding to large-scale cavity cloud shedding, accompanying with pressure fluctuations increasing. With the air injection rate further increase, the pressure fluctuations decrease. Air injection can significantly reduce the unsteady pressure fluctuations spectral content in the frequency range of 1 kHz to 10 kHz. For the bubbly shock propagation mechanism condition, air injection can avoid the formation and propagation of the bubbly shock and suppress both the pressure peaks and pressure fluctuations. With the increase in the air injection rate, the unsteady pressure fluctuations are further suppressed. The unsteady pressure spectral content between 0.2 kHz and 10 kHz is effectively reduced. [ABSTRACT FROM AUTHOR]

This paper develops a variational Bayesian approach for identifying ARX models with missing observations and varying time-delays. The outputs of the ARX models are subject to both slow sampling rates and communication delays. The unknown missing observations which are used in the variational Bayesian approach can be estimated by a modified Kalman filter, and based on the estimated missing observations and available data, the unknown parameters and the varying time-delays can be estimated by using the variational Bayesian approach. The simulation results demonstrate that the variational Bayesian method is effective. [ABSTRACT FROM AUTHOR]

The objective of this paper is to numerically investigate the cavitating flow around a marine propeller and to explore the intrinsic relationships between the sheet cavitation and its radiation noise. The k - ω SST turbulence model with the turbulence viscosity correction and the Zwart cavitation model are introduced to the simulation of cavitating flow around a propeller in a non-uniform wake. The loading noise and cavitation noise have been predicted based on the theory for acoustic fan source and the sound radiation theory for spherical bubble respectively. The periodic cavitation development has been captured, and the periodic large pressure fluctuation around the blade has been analyzed with the dominant frequencies in accordance to the first order of the blade passing frequency. For the non-cavitation case, the high sound pressure levels mainly concentrate in the low frequency stage and decrease from the low-order to the high-order blade passing frequency. While for the sheet cavitation case, the sound pressure level at the high-order of blade passing frequencies are enhanced. The sound pressure induced by the cavitation development is periodically varied accompanied with the periodic pulsating cavity evolution, and the acoustic energy mainly focus on the low order of blade passing frequencies. [ABSTRACT FROM AUTHOR]