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In this paper, a series of novel Sr3-xGa2Ge4O14:xDy3+ (x = 0 - 0. 40) (mole fraction) and Sr2.68Ga2Ge4O14 :0. 16Dy3+, 0. 16M+ (M = Li, Na, K) phosphors were prepared by high-temperature solid-phase method. EDS analysis confirms the presence of Sr, Ga, Ge, O and Dy elements in the phosphors. The series Sr3-xGa2Ge4O14 :xDy3+ produce strong yellow light emission with 568 nm as the dominant wavelength under 350 nm optical excitation, corresponding to the 4F9/2→6H13/2 transition. The emission spectra of the phosphor show that the emission intensity varies with the increase of Dy3+ concentration and reaches its maximum at x = 0. 16. The co-doping of alkali metal M(M = Li, Na, K) as a charge compensation ion, among which Li+ has the most obvious effect on increasing the emission intensity of Dy3+, led to the increase of the emission intensity of the phosphor to twice that of the phosphor in the absence of the charge compensation ion. In addition, the fluorescence lifetime of the phosphor decrease continuously with the increase of Dy3+ doping concentration. Finally, the CIE chromaticity coordinates and thermal stability of the phosphor Sr2.68Ga2Ge4O14 :0.16Dy3+, 0.16Li+ are explored, and its CIE chromaticity coordinates are (0. 371 9, 0.404 6), which are located in the yellow region, and its luminescence intensity at 453 K is about 95. 5% of its room temperature luminescence intensity. Therefore, Dy3+, Li+ co-doped Sr3-xGa2Ge4O14 phosphor is a potential candidate material for display devices and white light LED devices. [ABSTRACT FROM AUTHOR]

A series of novel Sr7Sb2O12:Dy3+ (x = 0 ~ 0.35) (mole percentage) phosphors were obtained by high temperature solid-state reaction. Its phase structure, luminescence properties, thermal stability and fluorescent decay lifetime were investigated. The characteristic emissions centered at 482 nm and 576 nm of Sr7Sb2O12:Dy3+ + were observed under the excitation light of 350 nm. When x = 0. 056, the Dy3+ concentration quench, and the Sr6.944Sb2O12 :0.056Dy3+ + CIE chromaticity coordinates are (0.340 8, 0.349 3). The quenching mechanism is attributed to the dipole-dipole interaction between Dy3+. When x=0. 14, the phosphors can emit white light with color coordinates (0.310 9, 0.314 0). In addition, the luminescence intensity of Sr7Sb2O12:Dy3+ at 453 K is about 83.3% of that at room temperature, showing good thermal stability. The above research results suggest that the Sr7Sb2O12:Dy3+ phosphor is expected to be used in UV-excited white light emitting diode. [ABSTRACT FROM AUTHOR]

The output voltage distortion of the inverter worsens the performance of the permanent-magnet synchronous motor, therefore, it should be compensated accurately. The inverter output voltage can be measured by the oversampling system, but the measured voltage contains drift and noise. To solve this problem, an adaptive sigmoidal function (S-function) model is first proposed in this article to estimate the voltage distortion. A nonlinear Levenberg–Marquardt regression method with voltage oversampling measurement is employed to identify the initial parameters of the adaptive S-function. During the operation, a recursive least square method is exploited to refresh the parameters of the S-function in realtime. The voltage distortion is accurately obtained by the proposed method, and an accurate compensation scheme is proposed to reduce the current distortion and torque ripple. The effectiveness of the proposed method is validated by experiments. [ABSTRACT FROM AUTHOR]

The processing quality of the block hole system affects the working performance of the marine diesel engine block directly. Choosing an appropriate combination of process parameters is a prerequisite to improving the accuracy of the block hole system. Uncertain fluctuations of process parameters during the machining process would affect the process reliability of the block hole system, resulting in an ultra-poor accuracy. For this reason, the RBF method is used to establish the relationship between the verticality of the cylinder hole and process parameters, including cutting speed, depth of cut, and feed rate. The minimum cylinder hole verticality is taken as the goal and the process reliability constraints of the cylinder hole are set based on Monte Carlo, a reliability optimization model of processing parameters for cylinder hole is established in this paper. Meanwhile, an improved particle swarm algorithm was designed to solve the model, and eventually, the global optimal combination of process parameters for the cylinder hole processing of the diesel engine block in the reliability stable region was obtained. [ABSTRACT FROM AUTHOR]

A series of new red-emitting Sr3Y2-xTeO9:xEu3+ phosphors were prepared by high temperature solid-state method, and the phase structure, luminescent performances, decay life and thermal stability of Sr3Y2-xTeO9:xEu3+ were studied. The results show that new red-emitting Sr3Y2-x TeO9: xEu3+ phosphors can emit intensive red light under near-ultraviolet or blue light excitation, and it demonstrate that the concentration quenching mechanism is attributed to the dipole-dipole interaction between Eu3+ ions. The color coordinates of these phosphors with different Eu3+ concentrations are in the red spectral region. The temperature-dependent luminescences emission spectra reveal that these phosphors show good thermal stability. The optimal doping concentration of Eu3+ is x = 0. 34 for Sr3Y2-xTeO9: xEu3+ phosphor, and its fluorescence decay lifetime is deduced to be 0. 619 ms. These overall results show that new red-emitting Sr3Y2-xTeO9:xEu3+ is promising phosphor applied in phosphor-converted near UV-excited white light-emitting diodes. [ABSTRACT FROM AUTHOR]

X-linked ubiquitin-specific peptidase 9 (USP9X) serves important roles in the development and progression of various human cancers. However, its role and molecular mechanism in liver cancer require further elucidation. In the present study, USP9X was found to be upregulated in liver cancer tissues. At the same time, overexpression of USP9X promoted the proliferation, invasiveness and migration of liver cancer cells, which were subsequently suppressed by USP9X silencing. On a molecular level, the results revealed that USP9X knockdown suppressed elements of the Janus kinase 2 (JAK2)/STAT3 signaling pathway, including JAK2, STAT3, matrix metalloproteinase-2 and c-Myc. By contrast, overexpression of USP9X had the opposite effect. In conclusion, the results of the present study suggest that USP9X is upregulated in patients with liver cancer, which may accelerate the proliferation, invasiveness and migration of liver cancer cells by regulating the JAK2/STAT3 signaling pathway. [ABSTRACT FROM AUTHOR]

The spatial-numerical association of response codes (SNARC) and Simon effects are attributed to the same type of conflict according to dimensional overlap (DO) theory: the congruency of task-irrelevant spatial information and the selected response (e.g., left or right). However, previous studies have yielded inconsistent results regarding the relationship between the two effects, with some studies reporting an interaction while others did not. This discrepancy may be attributed to the use of different types of Simon effects (visuomotor and cognitive Simon effects) in these studies, as the spatial codes associated with these two types of Simon effects are distinct (exogenous and endogenous, respectively). The aim of this study was to address these inconsistencies and gain a better understanding of the similarities and differences in spatial representations generated by spatial location, semantic information, and numerical information. We attempted to classify the relationships among the SNARC and Simon effects. Specifically, the visuomotor Simon, cognitive Simon, and SNARC effects were compared from three perspectives: the response time (RT) distribution, hand-stimulus proximity, and temporal dynamics (with the drift diffusion model; DDM). Regarding RTs, the results showed that the visuomotor Simon effect decreased with increased values of RT bins, while the cognitive Simon and SNARC effects increased. Additionally, the visuomotor Simon effect was the only effect influenced by hand-stimulus proximity, with a stronger effect observed in the hand-proximal condition than in the hand-distal condition. Regarding the DDM results, only the visuomotor Simon effect exhibited a higher drift rate and longer non-decision time in the incompatible condition than in the compatible condition. Conversely, both the SNARC and cognitive Simon effects exhibited an inverse pattern regarding the drift rate and no significant difference in non-decision time between the two conditions. These findings suggest that the SNARC effect is more similar to the cognitive Simon effect than the visuomotor Simon effect, indicating that the endogenous spatial-numerical representation of the SNARC effect might share an underlying processing mechanism with the endogenous spatial–semantic representation of the cognitive Simon effect but not with the exogenous location representation of the visuomotor Simon effect. Our results further demonstrate that the origin of spatial information could impact the classification of conflicts and supplement DO theory. [ABSTRACT FROM AUTHOR]

Fast and accurate visual scene understanding in autonomous vehicles is necessary but still very challenging. An autonomous vehicle must be taught to read the road like a human driver for better controlling the vehicle, so it is important to efficiently detect the road area and road markings. In this paper, we mainly focus on the vanishing point detection and its application in inverse perspective mapping (IPM) for road marking understanding. We first propose a fast and accurate vanishing point detection method for various types of roads, by adopting and improving Weber local descriptor to obtain salient representative texture and orientation information of the road area, and then voting for the dominant vanishing point with a simple line-voting scheme. Experimental results demonstrate that the proposed vanishing point detection approach gains a better performance than some state-of-the-art methods in terms of accuracy and computation time. Furthermore, we introduce the detected vanishing point into the IPM algorithm in the structured road environment, since some important calibration parameters can be automatically calculated by the vanishing point, especially on the rough road. Experiments also show that our proposed vanishing point-based IPM method is adaptive and accurate, which is conducive to the subsequent road marking detection and recognition. [ABSTRACT FROM AUTHOR]

Scanning electron microscopy (SEM) is of great importance for studying fractal permeability. In this work, we presented a new technique, by applying the high-order upwind compact difference schemes to solve the hyperbolic conservation laws, to enhance textural differences for accurate segmentation of the SEM images. From the enhanced SEM images, the channels and pores can be obtained by using the two-stage image segmentation. Combining with the box counting method, the key parameters for evaluation of the fractal permeability such as the tortuosity fractal dimension, the pore area fractal dimension and the maximum pore area can be derived from the segmented images. Application of the technique to the SEM images of a red sandstone from south China shows remarkable enhancement of edge details, allowing the more accurate segmentation of the SEM images. Rather than the original image algorithm, the fractal permeability derived from this new approach is closer to the experimental value, especially when the magnification falls in the range of 500-600. The results evidence that our enhanced images approach may provide stronger constraints on evaluations of permeability of sandstones. [ABSTRACT FROM AUTHOR]

Although the quartz accelerometer has made great advances, the performance, in some specific applications such as tilt sensing, needs to be well compensated in high temperature environment. Based on the high temperature testing of low cost quartz accelerometers, we found that the normalized positive and negative parts are asymmetrical at high temperature and the temperature curve of zero sensor output is related to the roll angle of the sensor. Traditional temperature compensation method only considers the temperature factor and ignores the roll sensitivity, which leads to deteriorated accuracy. To solve this problem, this paper proposes a novel and simple mathematical model to obtain a more accurate expression of zero sensor output, which makes the sensor output more robust at high temperature. Experimental results on two low cost quartz accelerometers demonstrate that the proposed model is feasible and effective, which could reduce the temperature drift error of the sensor output typically from 0.01 g to 0.001 g. Furthermore, we introduce the compensated sensors in the three-axis inclinometer system for tilt sensing, and the evaluation results show that the temperature drift error of the inclination in the range (20∘C, 150∘C) is reduced typically from 0.4∘ to 0.1∘ compared to the traditional method. [ABSTRACT FROM AUTHOR]

• A parametric design approach of composite external shading system for classroom is proposed. • The structural dimensions of the integrated external shading boards are obtained. • The structural dimensions of the perforated shading panel are obtained. • The optimal composite external shading system has good lighting and energy performance. • The approach is suited for designing a composite external shading system for the classroom. Energy consumption and visual comfort are issues worthy of concerning in the teaching buildings. To improve the light and thermal environment in the classroom, structural dimension parameters of shading system are optimized by the multi-objective genetic algorithm based on the lighting, energy consumption, and visual comfort in this study. The 3D parametric modeling of the classroom is performed by using the Grasshopper and Rhino software, and the quantitative impact of the integrated external sunshade and perforated external shading panel on the lighting, air conditioning and heating energy consumption, and visual comfort of the classroom are analyzed by the Radiance, Daysim, and EnergyPlus calculation engines. Subsequently, the optimal structural dimensions of the composite shading system in the east, west, south, and north orientations in Nanchang area are determined. The optimized results show that the optimal dimensions (width of the vertical shading board W; overhang length of the horizontal shading board L) of the integrated external shading boards in the east, west, south, and north orientations for the established classroom model are (0.3; 1.8), (0.6; 1.2), (0.4; 0.8), and (0.5; 0.7), respectively, as well as the optimal structural dimensions of the perforated shading panels (perforated panel to window ratio – perforation percentage – holes arrangement) are 71.5%–30%–crossing arrangement, 70%–50%–crossing arrangement, 90%–30%–crossing arrangement, and 65.6%–70%–matrix arrangement, respectively. It is found that total annual energy use intensity is reduced by 4.5% to 18.8%, the lighting quality in the near-window region (region I) is improved by 25% to 37%, the visual comfort in the classroom is improved by more than 30%, and the solar irradiance of the window is reduced by at least 27%. The proposed design approach of the classroom external shading system can not only greatly improve indoor lighting quality and visual comfort but also reduce total annual energy use intensity. [ABSTRACT FROM AUTHOR]

Abstract: This paper proposes a novel method for visual saliency detection based on an universal probabilistic model, which measures the saliency by combining low level features and location prior. We view the task of estimating visual saliency as searching the most conspicuous parts in an image and extract the saliency map by computing the dissimilarity between different regions. We simulate the moving of the center of human visual field, and describe how the center shift process works on visual saliency. Furthermore, multiscale analysis is adopted for improving the robustness of our model. Experimental results on three public image datasets show that the proposed approach outperforms 18 state-of-the-art methods for both salient object detection and human eye fixation prediction. [Copyright &y& Elsevier]

• The solidification microstructures of Fe-68wt.%Sn alloy powders commonly present "irregular" core/shell structure. • The average velocity of airflow on the windward side of powder is faster than that on the leeward side. • The core-deviated structure fundamentally originates from the asymmetric coagulation of minority phase inside the powder. • The observed structures of powder are strongly dependent upon the position and orientation of cross-sectional plane. Immiscible alloy powders with core/shell structure have recently garnered considerable interest due to their excellent industrial performance. However, a frequently observed yet often overlooked feature is the presence of core-deviated structure in various cross-sectional planes of the powder. To date, limited research has been conducted on this structure and its origin, leaving the formation mechanism unclear. Gaining a comprehensive understanding of this mechanism is crucial for advancements in powder materials research. In this study, we first analyzed the solidification microstructures of Fe-68 wt.%Sn alloy powders, followed by a numerical analysis of airflow and internal temperature fields within a powder during the free-falling process. Our findings revealed that the average airflow velocity on the windward side is faster than that on the leeward side, causing the highest temperature point within the powder to shift towards the leeward side over time. This phenomenon is fundamentally linked to the formation of the core-deviated structure. Furthermore, we explored the relationship between cross-sectional planes and potential microstructures, demonstrating that the final observed structures are strongly influenced by the position and orientation of the cross-sectional plane. Additionally, the core deviation distance was theoretically predicted and found to be consistent with experimental results in Fe-68 wt.%Sn powders. This research provides valuable insights into the actual solidification process of immiscible alloy powders and contributes to the development of specialized structural materials. [ABSTRACT FROM AUTHOR]

Building the forest fire prevention road in mountainous areas is an effective means to prevent forest fire from spreading wantonly. Nevertheless, adverse influences are that the construction of these roads has destroyed the inherent stability of the original slope, resulting a large number of unstable slopes appear in the catchment, which could trigger human-generated landslides and debris flows. On June 17, 2022, a landslide-generated debris flow occurred in the Longjiagou catchment, Mianning County, Sichuan Province. The initial landslide that induced this debris flow is one of the unstable slopes on the forest fire prevention road. After the debris flow event, we conducted a detailed on-site investigation of the Longjiagou catchment. Many unstable slopes have been found near the road, and the width of cracks at the rear edge of some unstable slopes has exceeded 10 cm. This is already a very dangerous precursor signal for landslides or debris flow. And several soil samples were collected in the catchment to test the hydraulic conductivity and particle size distribution of soil at different locations. Combined with multi-source data, we comprehensively analyzed the cause and mechanism of the disaster. The dynamic process modeling framework of earth-surfaced flow—Massflow—was adopted to simulate the dynamic process of the debris flow to support the quantitative analysis of this disaster. The results show that the simulation results are basically consistent with the actual situation. Based on field reconnaissance and numerical simulation, the mechanism of debris flow is comprehensively analyzed, which can provide important insights and guidance for the prediction and prevention of such debris flow disasters. [ABSTRACT FROM AUTHOR]

The conventional numerical solvers for partial differential equations encounter a formidable challenge, as their computational efficiency and accuracy are heavily contingent on grid size. Recently, machine learning (ML) has exhibited substantial promise in addressing partial differential equations. Nevertheless, substantial hurdles persist in practical applications. In this work, we endeavor to establish a deep learning framework founded on the Fourier neural operator (FNO) for resolving the intricacies of simulating real landslide dynamic processes. Our findings demonstrate that the current FNO approach adeptly replicates landslide dynamic processes and boasts exceptional computational efficiency. Additionally, it is noteworthy that this data‐driven ML methodology can seamlessly incorporate data from other experimental sources or numerical simulation techniques. Consequently, this work underscores the significant potential of utilizing ML methodologies to supplant conventional numerical simulation methods. Plain Language Summary: There are great challenges involved in leveraging machine learning methods to learn realistic physical dynamic processes. When it comes to the real landslide movement across intricate terrains, it is meaningful to validate the capacities of machine learning in tackling the complicated problem. This study aims to propose an innovative solution of modeling of landslide dynamic processes from a machine learning perspective. Here, we introduce a data‐driven framework based on Fourier neural operator to predict the dynamic behavior of actual landslides. Following an exhaustive assessment, the superior performance of our suggested model in real landslide situations and its versatility in adapting to landslides across various geographical regions have been confirmed. This study explores a new approach to modeling landslide dynamic processes and highlights the great potential of data‐driven approaches to address dynamic process challenges present in real physical world. Key Points: The data‐driven deep learning method based on FNO can achieve fast prediction of real landslide accumulation processThe proposed data‐driven method for predicting landslide dynamic processes can be extended to new areas after transfer learningWe provide numerical datasets of landslide dynamics, which can serve as the foundational resources for ML‐based landslide forecasting tasks [ABSTRACT FROM AUTHOR]

In order to improve the performance of interior permanent magnet synchronous machine (IPMSM) based on space voltage vector modulation schemes, this paper presents a highly accurate online method to find the proper maximum-torque-per-ampere (MTPA) angles. This algorithm fully considers the nonlinear characteristics of the d-axis inductance, q-axis inductance, and permanent magnetic flux together. Additionally, the influences of temperature are taken into account. In this paper, the proposed method injects a small virtual angle signal into the current angle mathematically to track the stator current reference angle that is close to real MTPA points. Moreover, following a theoretical analysis method, the error of the virtual signal injection method is analyzed. Then, based on the results of error analysis, this paper proposes a compensation strategy that can significantly reduce the current angle error between the tracking point and real MTPA point. At last, various experiments on an IPMSM test bench verify the proposed control technique and overall performance. [ABSTRACT FROM AUTHOR]

Activated oncogenes and loss of tumor suppressors contribute to reprogrammed energy metabolism and induce aerobic glycolysis, also known as Warburg effect. MicroRNAs are profoundly implicated in human malignancies by inhibiting translation of multiple mRNA targets. Using hepatocellular carcinoma (HCC) molecular profiles from The Cancer Genome Atlas (TCGA), we identified a handful of dysregulated microRNA in HCC glycolysis, especially miR‐34c‐3p. Antagonization of miR‐34c‐3p inhibited the lactate production, glucose consumption, extracellular acidification rate (ECAR), and aggressive proliferation in HCC cells. Hijacking glycolysis by 2‐deoxy‐d‐glucose or galactose largely abrogated the suppressive effects of miR‐34c‐3p inhibition in HCC. Membrane associated guanylate kinase, WW, and PDZ domain containing 3 (MAGI3) is then identified as a direct functional target of miR‐34c‐3p in regulating HCC glycolysis and oncogenic activities. Mechanistically, MAGI3 physically interacted with β‐catenin to regulate its transcriptional activity and c‐Myc expression, which further facilitates the Warburg effect by increasing expression of glycolytic genes including HK2, PFKL, and LDHA. Moreover, overexpressed miR‐34c‐3p and reduced MAGI3 predicted poor clinical outcome and was closely associated with the maximum standard uptake value (SUVmax) in HCC patients who received preoperative 18F‐FDG PET/CT. Our findings elucidate critical several microRNAs implicated in HCC glycolysis and reveal a novel function of miR‐34c‐3p/MAGI3 axis in Warburg effect through regulating β‐catenin activity. [ABSTRACT FROM AUTHOR]

The heat and mass transfer in the ablation process is of great importance for the ablation protection engineering. Accurate temperature assessment can provide effective support for the design of thermal protection structure and ablative material of reentry hypersonic vehicle. In this work, we studied the effect of permeability on heat and mass transfer and ablation thermal protection of gases produced during ablation. Since the carbide formed by ablation of material is a typical porous medium, its structure has self-similarity and can be described by fractal theory. Taking into account the angle of global coordinates and the local coordinates, this paper derived the permeability in any direction as a function of three different fractal dimensions in x , y and z directions. In order to verify the correctness of this method, the new model is introduced into the ablation process. Aiming at the ablation process and the diffusion equation of pyrolysis gas in the carbide layer, the temperature, material density and pyrolysis gas density distribution of three-dimensional spherical head under different permeability were simulated numerically. It is found that the permeability of carbides formed by ablative reaction of ablative materials related to fractal structure has an effect on ablation process. From our preliminary results, the higher the permeability, the faster the ablation speed, and the more obvious the overall temperature rise is. [ABSTRACT FROM AUTHOR]

The local spatio-temporal descriptor and feature encoding algorithm are two crucial key steps for human action recognition based on spatio-temporal interest points (STIP). Since the local descriptors for STIP are essentially a type of motion information based on the texture, the key point of local feature description is to extract invariable, robust and distinguishable local texture features and motion information in reference spatio-temporal volume. Scattering transform is an image transform method based on directional wavelet transform and scale convolution, which has local translation invariance, rotation invariance and elastic deformation stability for local texture features. A novel local descriptor for STIP based on spatio-temporal three-dimensional scattering transform is proposed in this paper, which extends the original scattering transform to spatio-temporal three-dimensional space. Compared to the traditional descriptors, such as HOG, HOF and so on, the proposed scattering transform coefficients based histogram of oriented gradients (STC-HOG) descriptor can capture more robust and distinguishable motion information of local texture for STIP. In order to incorporate the local descriptors into action video representation, the feature encoding algorithm is indispensable. For the problem that vector of locally aggregated descriptors (VLAD) loses feature distribution location information during feature encoding, a histogram of distribution vector of locally aggregated descriptors (HOD-VALD) based on Gaussian kernel is proposed. We validated the proposed algorithm for human action recognition on multiple public available datasets, such as KTH, UCF Sports, HMDB51 and so on. The evaluation experiment results indicate that the proposed descriptor and encoding method can improve the efficiency of human action recognition and the recognition accuracy. [ABSTRACT FROM AUTHOR]

Takayasu arteritis (TAK) is a chronic granulomatous vasculitis with an unknown etiology that often manifests over time. It has a dismal prognosis and is currently clinically refractory. The theory of poisonous evil has drawn more attention in recent years in the treatment of autoimmune disorders. Poisonous evil tends to accumulate and transform into heat, which causes a variety of symptoms to gradually emerge. Our team believes that the main cause of TAK is the prolonged stagnation of poisonous evil, the transformation of heat into fire, and the damage to the vessels and collaterals. Blood stasis is the basic pathogenesis. This disease is located in the blood vessels, which is also closely related to the spleen and kidney. TAK also belongs to a deficiency in origin and excess in superficislity. Kidney and spleen deficiencies, and a lack of essence and blood, cause only partially filled blood vessels and restricted blood flow. The collection of evil qi and the transformation of heat-toxin culminates in the accumulation of heat-toxin and congestion of blood vessels. The illness persists and the evil qi remains and penetrates the internal organs, causing a lack of vital qi, and the viscera loses its nourishment. Unblocking the blood vessels and boosting blood circulation is the cornerstone of clinical treatment. The focus of treatment is on removing heat-toxin during the active phase, while during the remission phase, the focus is on strengthening the spleen and kidney, nourishing the vessels, taking into consideration detoxification, and dredging collaterals. The goal of the cicatricial period is to dredge collaterals in order to enrich vital qi. Based on relevant theories of traditional Chinese medicine and pathological mechanisms research of western medicine, the significance of heat-toxin in the pathogenesis of TAK is explained. Our team believes that the heat-toxin in blood vessels developing into lumps is the vasculature are the cause of the disease's morbidity. The heat-toxin can be cleared to remove blood stasis and eliminate lumps, which will improve clinical symptoms, slow the disease's progression, and provide ideas for clinical treatment. [ABSTRACT FROM AUTHOR]

Aim: To evaluate the value of the second‐trimester fibronectin concentration, alone and in combination with other markers (e.g., mean arterial pressure, inhibin A), in the identification of women who subsequently develop severe preeclampsia. Methods: For this prospective nested case–control study, serum from pregnant women (gestational age 15–22 weeks) who underwent routine Down syndrome screening was analyzed. The women were tracked to delivery and assigned to the severe preeclampsia or control group, according to whether they developed severe preeclampsia. Each woman who later developed severe preeclampsia was paired with five healthy women with pregnancies of similar gestational age (± 1 week). Fibronectin, inhibin A, human chorionic gonadotropin, placental growth factor, cysteine, and homocysteine concentrations were measured in 44 cases in the severe preeclampsia group and 220 cases in the control group. The body mass index and mean arterial pressure were calculated. All results were compared between the two groups. Logistic regression analysis and receiver operating characteristic curve construction were conducted for markers differing significantly between two groups. Results: The second‐trimester fibronectin value was positively correlated with severe preeclampsia and predicted 67.7% of severe preeclampsia cases. The combination of fibronectin, inhibin A, and mean arterial pressure predicted 76.7% of severe preeclampsia cases; predictive values for combinations of fibronectin with mean arterial pressure or inhibin A were 75.4% and 74.6%, respectively. Combination with these other markers increased the predictive value of fibronectin. In addition, fibronectin was more powerful for the late severe preeclampsia and severe preeclampsia without fetal growth restriction subgroups. Conclusions: The second‐trimester fibronectin concentration can be used to predict severe preeclampsia. [ABSTRACT FROM AUTHOR]

Facial expression recognition (FER) has been a challenging task in the field of artificial intelligence. In this paper, we propose a novel model, named regional self-attention convolutional neural network (RSACNN), for FER. Different from the previous methods, RSACNN makes full use of the facial texture of expression salient region, so yields a robust feature representation for FER. The proposed model contains two novel parts: regional local multiple pattern (RLMP) based on the improved K-means algorithm and the regional self-attention module (RSAM). First, RLMP uses the improved K-means algorithm to dynamically cluster the pixels to ensure the robustness of texture features with expression salient variation. Besides, the texture description is enhanced by extending the binary pattern to the multiple patterns and integrating the information of gray difference between pixels in the region. Next, RSAM can adaptively form weights for each region through the self-attention mechanism, and use rank regularization loss (RRLoss) to constrain the weights of different regions. By jointly combining RLMP and RSAM, RSACNN can effectively enhance the feature representation of expression salient regions, so that the performance of expression recognition can be improved. Extensive experiments on public datasets, i.e. CK + , Oulu-CASIA, Fer2013 and SFEW, prove the superiority of our method over state-of-the-art approaches. [ABSTRACT FROM AUTHOR]

With more color images being widely used on the Internet, the research on embedding color watermark image into color host image has been receiving more attention. Recently, Su et al. have proposed a robust and blind watermarking scheme for dual color image, in which the main innovation is the using of two-level DCT. However, it has been demonstrated in this paper that the original scheme in Su’s study is not secure and can be attacked by our proposed method. In addition, some errors in the original scheme have been pointed out. Also, an improvement measure is presented to enhance the security of the original watermarking scheme. The proposed method has been confirmed by both theoretical analysis and experimental results. [ABSTRACT FROM AUTHOR]

In tectonically active steep mountain belts, such as those in west Sichuan in China, frequent landslide disasters can occur during the rainy season. High-locality landslides often initiate with the failure of fractured rock masses or regolith near the ridge of a high and steep slope. Often, these events occur suddenly in the sense that people downslope are caught by surprise. High-locality landslides can be destructive owing to the large momentum and entrainment potential of the moving mass. Increasing attention has been given to these events since the 2008 Wenchuan earthquake. Indeed, slope ridges are particularly susceptible of topographic amplification of the seismic shaking, resulting in mechanical weakening that predisposes them to enhanced weathering and rain-triggered failures years or decades after the mainshock. Risk reduction in such cases must begin with a systematic surveying of the ridges to identify criticalities. Then, quantitative (numerical) approaches must be used to evaluate volumes and describe the movement. Risk assessments can then be produced, and mitigations suggested. Here, we describe the Tonghua landslide in Li County, which is currently in a creeping stage but threatens critical infrastructures and dwellings. We monitored the site for 3 years and identified additional potentially unstable areas before performing physically based modeling and hazard zonation. Our results could be useful in decision-making for risk reduction. [ABSTRACT FROM AUTHOR]

N170 is a negative event‐related potential (ERP) component in response to visual stimuli, such as faces. It remains controversial whether N170 reflects the specific processing of faces or can also be elicited by objects of expertise (e.g., words). In this research, we conducted a meta‐analysis for the spatiotemporal characteristics of N170 of face and word stimuli from 24 studies in which both stimuli were presented for each subject. We observed that (1) both face and word stimuli can elicit conspicuous N170s and that there was no difference between the amplitude of face‐N170 and word‐N170; (2) there is no difference in the latencies between the two N170s; and (3) both N170s are distributed in the occipitotemporal regions but with a reversed hemispheric distribution pattern—face‐N170 is more negative in the right than left occipitotemporal regions, while word‐N170 is the opposite. These results showed that the face‐ and word‐N170s are qualitatively the same but have different hemispheric lateralization advantages—N170 might be a general neural index of the expertise‐dependent object‐recognition process in occipitotemporal regions. [ABSTRACT FROM AUTHOR]

Background: Waste anesthetic gases (WAGs) leaked from new-type halogenated inhalational anesthetics such as sevoflurane have been were reported to pose a risk for the health of operating room personnel. The effects of WAGs on peripheral blood lymphocytes, however, remain yet controversial. The present study was undertaken to examine the effects of occupational sevoflurane exposure on the peripheral blood lymphocytes of medical personnel who work in the operating room. Methods: A cohort of 56 medical residents were divided into exposed group (n = 28) and control group (non-exposed group) (n = 28). Gas chromatography was used to measure the concentration of sevoflurane in the medical resident's breathing zone during surgeries under inhalation anesthesia in the exposure group. The gas collection lasted an hour. Peripheral blood lymphocytes were isolated from venous blood, and then apoptosis and cell cycle were analyzed by flow cytometry. EDTA-anticoagulated whole blood was harvested to analyze the lymphocyte subsets by flow cytometry. Immunoglobulins (IgA, IgM, IgG) were quantified by immunoturbidimetry. Results: The average concentration of sevoflurane in the exposed group was 1.03 ppm with a range from 0.03 ppm to 2.24 ppm. No significant effects were found on the apoptosis rates or cell cycles of peripheral blood lymphocytes in the exposed group relative to the control group (P > 0.05). Similarly, there were no significant differences in the lymphocyte subsets or the levels of immunoglobulins (IgA, IgM, IgG) between the two groups (P > 0.05). Conclusions: Occupational exposure to low-level sevoflurane has no significant effect on the peripheral blood lymphocytes of operating room staff, but this conclusion needs to be confirmed by multicenter and long-term follow-up studies with large samples. Trial registration number and date of registration: ChiCTR2000040772, December 9, 2020 (Retrospective registration). [ABSTRACT FROM AUTHOR]

Background: Hepatocellular carcinoma (HCC) is a common malignant tumor with poor prognosis. Magnetic resonance imaging (MRI) is one of the most effective imaging methods for the early diagnosis of HCC. However, the current MR contrast agents are still facing challenges in the early diagnosis of HCC due to their relatively low sensitivity and biosafety. Thus, the development of effective MR agents is highly needed for the early diagnosis of HCC. Results: Herein, we fabricated an HCC-targeted nanocomplexes containing SPIO-loaded mesoporous polydopamine (MPDA@SPIO), sialic acid (SA)-modified polyethyleneimine (SA-PEI), and alpha-fetoprotein regulated ferritin gene (AFP-Fth) which was developed for the early diagnosis of HCC. It was found that the prepared nanocomplexes (MPDA@SPIO/SA-PEI/AFP-Fth) has an excellent biocompatibility towards the liver cells. In vivo and in vivo studies revealed that the transfection of AFP-Fth gene in hepatic cells significantly upregulated the expression level of ferritin, thereby resulting in an enhanced contrast on T2-weighted images via the formed endogenous MR contrast. Conclusions: The results suggested that MPDA@SPIO/SA-PEI/AFP-Fth had a superior ability to enhance the MR contrast of T2-weighted images of tumor region than the other preparations, which was due to its HCC-targeted ability and the combined T2 contrast effect of endogenous ferritin and exogenous SPIO. Our study proved that MPDA@SPIO/SA-PEI/AFP-Fth nanocomplexes could be used as an effective MR contrast agent to detect HCC in the early stage. [ABSTRACT FROM AUTHOR]

Pumped storage power plants, which is known as only large-scale energy management equipment, plays a vital important role in energy field. Hump characteristic and S characteristic are two classical unsteady hydraulic characteristics when pump-turbine operating at turbine mode and pump mode, respectively. It has been found that these two characteristics are both strongly related to the complex vortex evolution process in vaneless region while only few papers focus on the elimination mechanism of them. In present paper, a scaled runner with optimized high-pressure side (HPS) is designed and manufactured based on multi-objective optimization process arming at eliminating unsteady characteristic, i.e. hump characteristic and S characteristic, while maintaining efficiency characteristic unchanged. Thereafter, hydraulic experiments are conducted to investigate the impact of HPS geometry on hydraulic performance (efficiency, hump margin, S margin and pressure fluctuation) of object pump turbine. The experimental results show that compared with the original runner, the weighted average efficiency for pump mode increases by 0.1% while the weighted average efficiency for turbine mode decreases by 0.1%. Moreover, the S margin increases from 76.7 m to 87.2 m and the S 2 unsteady region is largely increased. The hump margin decreases a little while it can recover to the original level through increasing 0.6% of the original ratio scale. Moreover, the runner with optimized HPS can effectively reduce the pressure fluctuation amplitude in vaneless region up to 33.3% and 21.4% for turbine mode and pump mode, respectively. • High-pressure of a pump-turbine runner is systematically optimized and tested for the first time. • The high-efficiency characteristic is inherited by the optimized runner. • The optimized runner increases S margin from 77 m to 87 m. • The optimized runner shows better performance in transient process at turbine mode. • Pressure fluctuation amplitude is reduced up to 33.3% and 21.4% at turbine mode and pump mode, respectively. [ABSTRACT FROM AUTHOR]

Adult human mesenchymal stem cells have the potential to differentiate into osteoblast, which plays crucial roles in bone regeneration and repair. Some transcriptional factors (TFs), such as BMP‐2 and RUNX2, have been demonstrated to control the differentiation processes. It is important to discover more key regulators in osteoblast differentiation. Recently, some studies found long noncoding RNAs (lncRNAs) participating in osteoblast differentiation, such as MALAT1, DANCR, and ANCR. In this study, we performed a network‐based computational analysis to investigate the lncRNA–messenger RNA (mRNA) crosstalks via integrating microRNA (miRNA)–RNA interactions, gene coexpression, and protein–protein interactions. First, multiple topology analyses were performed to osteoblast‐differentiation‐related lncRNA–mRNA network (ODLMN). Several lncRNAs with central topology structures were identified as key regulators. Results showed that these lncRNAs participated in osteoblast differentiation via phosphoinositide 3‐kinase (PI3K), mitogen‐activated protein kinase, and Ras signals. Previous studies have demonstrated that lncRNAs exert functions by involving in close modules. Second, after performing module searching in ODLMN, two functional modules were identified, which played crucial roles through involving in PI3K/protein kinase B, cyclic adenosine 3ʹ,5ʹ‐monophosphate, and hypoxia‐inducible factor 1 pathways. Third, a subset of core lncRNA–TF crosstalks that might form feedback loops to control the biological processes in osteoblast differentiation was identified. These core lncRNA–TF feedback loops showed more TF binding affinity than other lncRNAs. All these results can help us to uncover the molecular mechanism and provide new targets for bone regeneration and repair. [ABSTRACT FROM AUTHOR]

Highlights • A comprehensive model was developed to describe the biomass char reactivity. • The model is based on the simple gas-solid collision theory and fractal theory. • The effects of thermal annealing and the pore breaking phenomenon were considered. • Good agreement is obtained between the model results and the experimental data. Abstract This study developed a model for the chemical reactivity of fresh biomass chars, and built a calculation equation for the char gasification rate using simple gas-solid collision theory (SCT). The effects of pore breaks, pore collapse and thermal annealing on the char reactivity were considered in the modelling. Experimental tests for six acid-washed biomass chars were performed under a CO 2 atmosphere and used a thermo-gravimetric analyzer (TGA) over the temperature range of 1073–1273 K. The results showed that the reactivity of fresh char could be predicted quantitatively by some characteristic properties of certain kind of biomass and their combined parameters. For the instability of the biomass char structure, the internal pore length and gasification temperature showed a good exponential relationship. Good agreement was achieved, and the applicability of the model was demonstrated by comparing the predicted results with experimental data. [ABSTRACT FROM AUTHOR]

The systemic investigation of the metabolic pathways associated with the hepatic tumorigenesis is important to discover novel biomarkers and identify the potential pathogenesis. Here, the 1H nuclear magnetic resonance- (1H NMR-) based metabolomic analysis was used to monitor the whole process of rat diethylnitrosamine-induced HCC. Intraperitoneal administration of diethylnitrosamine (DEN) was used to induce primary HCCs in male Sprague-Dawley rats. Magnetic resonance imaging (MRI) examinations were performed to follow the tumor formation and growth in the liver and H&E staining was used to confirm MR imaging findings. The rats with DEN treatment and control rats without DEN were euthanized at the time points of 3, 8, and 15 weeks after the start of modeling. 1H NMR-based metabolomic analysis was used to explore hepatic metabolite changes and certify key metabolic pathways in the process of tumor tumorigenesis. Our MRI results depicted the formation of HCC nodules in ten rats 14 weeks after DEN injection which were confirmed by histology. Twenty-four different metabolites were identified and quantified by 1H NMR spectroscopy; OPLS-DA models and corresponding VIP plots analysis further identified ten metabolites associated with the abnormal metabolism. The aberrant glucose, lipid, and glutathione-glutamine-glutamate metabolism could be detected involving in the process of hepatic tumorigenesis, which provides an important evidence for the in-depth study of subsequent molecular mechanisms, especially the glutathione-glutamine-glutamate metabolism. [ABSTRACT FROM AUTHOR]

• Thermal performance of the spray cooling double skin facade is experimentally investigated. • Impact of ventilation mode on the spray cooling effect of double skin facade are compared. • Impact of operation time on the spray cooling effect of double skin facade are compared. • Impact of spray direction on the spray cooling effect of double skin facade are compared. • The appropriate operation mode of the spray cooling double skin facade in hot humid climate is obtained. Thermal performance of the spray cooling double skin façade in hot and humid climate region are experimentally investigated in this study. Two identical double skin facades are constructed for the comparative analysis. Thermal performance of the spray cooling double skin façade is evaluated by the indicators of cavity air temperature, glass surface temperature, the U-value, and solar heat gain coefficient. The influences of the ventilation mode (open conditions of the top and bottom vents in the double skin façade system), operation time (spray and interval time of the spray system), and spray direction on the cooling effect of the spray cooling double skin façade are experimentally compared and analyzed, and the operation mode of the spray cooling double skin façade with the best thermal performance is obtained. The results demonstrate that the appropriate operation mode of the spray cooling double skin façade is that the top and bottom vents are opened, and the spray direction is from up to down with the operation time of 10/15 min (spray/interval time). The average temperature of the cavity and inner glass decreased by 8.1 °C and 3.7 °C, respectively. The mean U-value and SHGC of the spray cooling double skin façade are 2.13 W/(m2·K) and 0.25, respectively, which are smaller than the most stringent limit values of the current national standard. The spray cooling double skin façade has good thermal performance in hot humid climate region in China. [ABSTRACT FROM AUTHOR]

On June 17, 2020, a large debris flow occurred in the Meilong catchment following a short-duration, high-intensity rainstorm. The debris flow was initiated by two shallow landsides upstream of the catchment and had a volume of approximately 7.7 × 105 m3. It blocked the river and then induced flooding, causing significant losses to the local residents. In this study, through a combination of field observation, image interpretation, and laboratory experiments, the initiation mechanism, erosion depth along the main channel, and deposition area of this debris flow were comprehensively analyzed. A sequentially integrated numerical model considering the rainfall interception by vegetation, infiltration, and runoff process was developed. Considering the spatial variations in the climatic, hydrological, and geotechnical parameters, the entire process of debris flow initiation, motion, entrainment, and deposition was simulated. The computational outcomes matched well with the field observation results. A combination of the proposed integrated model and spatially varying parameters can be used to effectively describe the debris flow characteristics in the initiation and propagation stages and provide significant insights into the physical processes involved in such hazards. • The Meilong debris flow was initiated by two shallow landsides upstream. • An integrated numerical model with spatial variations of parameter is developed. • The computational outcomes of debris flow match well with the field observation. • A well-monitored groundwater data should be available to predict shallow landslides. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we consider the problem of recognizing human faces from frontal views with varying illumination, as well as occlusion and disguise. Motivated by the latest research on the recovery of low-rank matrix using robust principal component analysis (RPCA), we present a novel approach of robust face recognition by exploiting the sparse error component obtained by RPCA. Compared with low-rank component, it is revealed that the associated sparse error component exhibits more discriminating information which is of benefit to face identification. We define two descriptors (i.e., sparsity and smoothness) to represent characteristic of the sparse error component, and give two recognition protocols (i.e., the weighted based method and the ratio based method) to classify face images. The efficacy of the proposed approach is verified on publicly available databases (i.e., Extended Yale B and AR) with promising results. Meanwhile, the proposed algorithm manifests robustness since it does not assume any explicit prior knowledge about the illumination conditions, as well as the nature of corrupted and occluded regions. Furthermore, the proposed method is not limited to face recognition, also can be extended to other image-based object recognition. [Copyright &y& Elsevier]

ABSTRACT In previous studies, HSPC016 was identified as a differentially expressed gene in dermal papilla cells (DPC) with aggregative behaviour. To clarify its role in the regulation of DPC, the recombinant HSPC016 protein was expressed using the Pichia pastoris expression system, and three small interfering ribonucleic acid duplexes (siRNA) were designed and transfected into DPC. Results showed that DPC with the HSPC016 gene inhibited, exhibit non-aggregative behaviour and grow much slower than normal DPC, and that the recombinant HSPC016 protein could promote the proliferation of high-passage DPC and induce its aggregative behaviour. [ABSTRACT FROM AUTHOR]

The dermal papilla plays pivotal roles in hair follicle cycle and dermal papilla cells (DPCs) with aggregative behavior have more obviously inductive ability. In the present study, the suppression subtractive hybridization method was employed to identify the differentially expressed genes in dermal papillae cells with aggregative behavior. Following mRNA isolation of DPC with and without aggregative behavior, cDNA of both populations were prepared and subtracted by suppression PCR. Sequencing of enriched cDNAs identified five genes differentially expressed including capping protein, paladin, and vascular endothelial growth factor. Interestingly, HSPC016, first cloned from CD34+ hematopoietic stem/progenitor cells (HSPC), was identified by SSH, cDNA dot blot and Northern blot, which showed that this gene was differentially expressed in DPC with aggregative behavior. The full-length cDNA of HSPC016 was shown to be 366 bp, and the possible function of HSPC016 related to transcriptional regulation. [ABSTRACT FROM AUTHOR]

The aim of this work is to understand the ignition and combustion behaviors of n -butane/air mixtures under glow plug ignition in the start-up condition of miniature IC engines. We utilized a centimeter-scale constant-volume chamber setup to investigate the effects of glow plug heating power, equivalence ratio, and initial pressure on the characteristics of ignition and flame propagation of n -butane/air mixtures. Results indicated that the ignition time and ignition temperature decrease as the heating power increases and the flame propagation time is weakly sensitive to that. Increasing the initial pressure can reduce the ignition time, decrease the ignition temperature and slow flame propagation; except for the flammable limit, the ignition time and ignition temperature increase as the equivalence ratio increases, in addition, the flame propagation is fastest at φ = 1.2. Furthermore, an obvious two-stage combustion phenomenon was observed under fuel-rich flame propagation conditions. Overall, the order of influencing factors on the ignition characteristics shows heating power > initial pressure > equivalence ratio, and that on the flame propagation characteristics shows equivalence ratio > initial pressure > heating power in present experimental conditions. [ABSTRACT FROM AUTHOR]

Background: Recent evidence suggests early screening of preeclampsia and small-for-gestational-age (SGA) would benefit pregnancies followed by subsequent prophylactic use of aspirin. Multi-marker models have shown capability of predicting preeclampsia and SGA in first trimester. Yet the clinical feasibility of combined screening model for Chinese pregnancies has not been fully assessed. The aim of this study is to evaluate the applicability of a multi-marker screening model to the prediction of preeclampsia and SGA in first trimester particularly among Chinese population.Methods: Three thousand two hundred seventy pregnancies meeting the inclusion criteria took first-trimester screening of preeclampsia and SGA. A prior risk based on maternal characteristics was evaluated, and a posterior risk was assessed by combining prior risk with multiple of median (MoM) values of mean arterial pressure (MAP), serum placental growth factor (PLGF) and pregnancy associated plasma protein A (PAPP-A). Both risks were calculated by Preeclampsia PREDICTOR™ software, Perkin Elmer. Screening performance of prior and posterior risks for early and late preeclampsia by using PREDICTOR software was shown by Receiver Operating Characteristics (ROC) curves. The estimation of detection rates and false positive rates of delivery with both preeclampsia and SGA was made.Results: Eight cases developed early preeclampsia (0.24%) and 35 were diagnosed as late preeclampsia (1.07%). Five with early preeclampsia and ten with late preeclampsia later delivered SGA newborns (0.46%); 84 without preeclampsia gave birth to the SGAs (2.57%). According to ROC curves, posterior risks performed better than prior risks in terms of preeclampsia, especially in early preeclampsia. At 10% false positive rate, detection rates of early and late preeclampsia were 87.50 and 48.57%, detection rates of early and late SGA were 41.67 and 28.00%, respectively. For SGA, detection rates in cases with preeclampsia were much higher than those in absence of it.Conclusions: This study demonstrates that combined screening model could be useful for predicting early preeclampsia in Chinese pregnancies. Furthermore, the performance of SGA screening by same protocol is strongly associated with preeclampsia. [ABSTRACT FROM AUTHOR]

Abstract: Background: Transmetatarsal amputation (TMA) is an operation designed to remove a limited area of irremediable tissue ischemia and/or infection and preserve limb function. Patients are selected for TMA based on degree of tissue loss/infection, adequacy of tissue perfusion at the transmetatarsal level, current ambulatory status, and estimation of the likelihood of postprocedure ambulation. The purpose of this study was to assess the validity of these selection criteria. Methods: An institutional review board–approved retrospective review was conducted of all patients undergoing TMA from January 1, 1997, until January 1, 2006. Information was collected on patient demographics, medical comorbidity, and clinical and surgical variables. Outcome measures included the proportion of patients requiring amputation revision to a more proximal level and ambulatory status at last follow-up. Results: Fifty-two TMAs were performed. In 35 procedures, the skin was left open, and in 17 TMA was closed primarily. Primary indications for the procedure were vascular insufficiency or infection in 50 of 52 patients, whereas 2 patients required amputation for malignancy. The majority (46/52, 89%) of patients were diabetic. After the index TMA, 85 additional operations were required. Only 9 patients (18%) underwent a single operation. Revision of the TMA to a more proximal level was required in 29 of 52 (56%) patients, resulting in 4 Syme, 20 transtibial, and 5 transfemoral amputations. Non–insulin-dependent diabetes was associated with an increased likelihood of revision to a more proximal amputation (odds ratio [OR] = 5.4; 95% confidence interval [CI], 1.2–24). At the time of last follow-up (median 18 months), 37 of 50 (74%) patients were ambulatory (83% for TMAs and 67% for more proximal amputations, P = 0.18). Prior vascular procedures were associated with a significantly decreased likelihood of ambulation (OR = 14; 95% CI, 1.9–103). Conclusions: Although most patients retain the ability to ambulate after TMA, multiple operations should be anticipated in the majority of patients and revision of a TMA to a more proximal level may be required. These data suggest that current selection criteria for TMA may be inadequate. [Copyright &y& Elsevier]