Search

Terrorism poses a significant threat to international peace and stability. The ability to predict potential casualties resulting from terrorist attacks, based on specific attack characteristics, is vital for protecting the safety of innocent civilians. However, conventional data sampling methods struggle to effectively address the challenge of data imbalance in textual features. To tackle this issue, we introduce a novel algorithm, GA-CatBoost-Weight, designed for predicting whether terrorist attacks will lead to casualties among innocent civilians. Our approach begins with feature selection using the RF-RFE method, followed by leveraging the CatBoost algorithm to handle diverse modal features comprehensively and to mitigate data imbalance. Additionally, we employ Genetic Algorithm (GA) to finetune hyperparameters. Experimental validation has demonstrated the superior performance of our method, achieving a sensitivity of 92.68% and an F1 score of 90.99% with fewer iterations. To the best of our knowledge, our study is the pioneering research that applies CatBoost to address the prediction of terrorist attack outcomes. [ABSTRACT FROM AUTHOR]

Highlights • Intake gas uniformity of the dual-stack PEM fuel cell system was studied. • Porous media model was proposed to replace fuel cell stack pressure drop model. • The model was proved to be reasonable by mechanism. • Several features of intake gas was found through simulation. Abstract The Polymer Electrolyte Membrane Fuel Cell (PEMFC) system is considered as one of the most potential power plant on vehicle. However, the efficiency of the high power fuel cell stack has restricted the high power system which is developed for the full power fuel cell vehicle. The multi-stack system integrated by several fuel cell stacks is a solution aimed for high power level system. However, the inconsistency of the stacks flow distribution restricts the performance uniformity of each stacks and the efficiency of the multi-stack fuel cell system. In this paper, a dual-stack polymer electrolyte membrane fuel cell system was setup, and its intake manifold was established. A porous medium was applied to replace the complex flow field structure inside the fuel cells to simulate the pressure drop of the gas through the stack. According to the operating conditions of the vehicle, variable conditions are designed to carry out simulation experiments for the first time. The results show that there is not a significant effect of the changing load's range on the instantaneous uniformity. However, the initial value of the changing load has a great influence on the instantaneous uniformity. In addition, the settling time of the loading process is much shorter than that of the load shedding process. The equivalent model of porous media proposed provides a new method to model the fuel cell stack, which is very useful in the fuel cell pipe system design and system dynamic response analysis. The uniformity simulation result provides the directions for the fuel cell control strategy design and optimization, and the references for gas intake manifold design. [ABSTRACT FROM AUTHOR]

The mass flux and pressure profile of the critical flow in a slit are connected to the original diameter and concentration of radioactive aerosols in leak-before-break monitoring in nuclear power plants. The Delayed Equilibrium Model (DEM), although accurate for mass flux and pressure prediction of critical flow in a circular tube, suffers from underprediction of the pressure drop for critical flow in the slit. In this study, an optimized DEM considering the shape effect of flash boiling is proposed by changing the saturated phase mass flow rate fraction gradient and two-phase friction coefficient multiplier in the DEM. Two novel equations for the new coefficients, C 4 and C 5 , are introduced in the optimization. The relative error of the critical flow pressure in the slit can be reduced using the optimized DEM. In addition, a sensitivity analysis of the original critical flow model is conducted and the mass flux and critical pressure of the critical flow model are found to be most sensitive to the inlet temperature. The effectiveness of the optimization proves that the shape effect of the velocity of achieving thermal equilibrium in flash boiling is critical for the critical flow in a slit. [ABSTRACT FROM AUTHOR]

This paper presents a new and enhanced fusion module for the Multi-Sensor Precipitation Estimator (MPE) that would objectively blend real-time satellite quantitative precipitation estimates (SQPE) with radar and gauge estimates. This module consists of a preprocessor that mitigates systematic bias in SQPE, and a two-way blending routine that statistically fuses adjusted SQPE with radar estimates. The preprocessor not only corrects systematic bias in SQPE, but also improves the spatial distribution of precipitation based on SQPE and makes it closely resemble that of radar-based observations. It uses a more sophisticated radar-satellite merging technique to blend preprocessed datasets, and provides a better overall QPE product. The performance of the new satellite-radar-gauge blending module is assessed using independent rain gauge data over a five-year period between 2003-2007, and the assessment evaluates the accuracy of newly developed satellite-radar-gauge (SRG) blended products versus that of radar-gauge products (which represents MPE algorithm currently used in the NWS (National Weather Service) operations) over two regions: (I) Inside radar effective coverage and (II) immediately outside radar coverage. The outcomes of the evaluation indicate (a) ingest of SQPE over areas within effective radar coverage improve the quality of QPE by mitigating the errors in radar estimates in region I; and (b) blending of radar, gauge, and satellite estimates over region II leads to reduction of errors relative to bias-corrected SQPE. In addition, the new module alleviates the discontinuities along the boundaries of radar effective coverage otherwise seen when SQPE is used directly to fill the areas outside of effective radar coverage. [ABSTRACT FROM AUTHOR]

To evaluate the rationality and limitations of the seventh edition of the American Joint Committee on Cancer (the 7th AJCC edition) T-staging system for locally advanced nasopharyngeal carcinoma (NPC). The prognosis of 358 patients with stage T3/T4 NPC treated with intensity-modulated radiotherapy (IMRT) was analyzed with the Kaplan–Meier method or the log-rank test. The 7th AJCC staging system of NPC has some limitations in that the T category is neither the significant factor in OS/LRFS nor the independent prognostic factor in OS/LRFS/DMFS/DFS (P>0.05). After adjustment by anatomic structures, univariate analysis has shown that the adjusted-T category has statistical significance between T3 and T4 for OS (86.4% and 71.3%, P=0.002), LRFS (97% and 90.9%, P=0.048), DMFS (90.9% and 77.2%, P=0.001), and DFS (86.2% and 67.5%, P=0.000), and multivariate analysis has shown that the adjusted-T category is an independent prognostic factor for OS/DMFS/DFS (with the exception of LRFS). Then, GTV-P was taken into consideration. Multivariate analysis showed that these nT categories serve as suitable independent prognostic factors for OS/DMFS/DFS (P<0.001) and LRFS (HR = 3.131; 95% CI, 1.090–8.990; P=0.043). The 7th AJCC staging system has limitations and should be improved by including the modifications suggested, such as anatomic structures and tumor volume adjustment. [ABSTRACT FROM AUTHOR]

With the development of magnetic confinement fusion research, higher magnetic fields are needed. Commonly used is Nb3Sn superconductor in high-field magnets, which does not have much potential for improvement. It is necessary to develop new conductor with new superconducting materials. Bi2Sr2CaCu2Ox is such a promising material. One sub-size conductor with 42 wires has been designed and manufactured at Institute of Plasma Physics Chinese Academy of Sciences (ASIPP) and its ac loss has been tested in the standard magnetization magnet for transverse magnetic fields at the University of Twente. The phenomenological model was used to analyze the test results. And the results showing that the coupling loss of Bi-2212 conductor is greater than that of Nb3Sn conductor under the same condition. This result may due to the fact that the silver matrix used in the Bi-2212 strands has a lower electrical resistivity than the copper matrix of the Nb3Sn strands. [ABSTRACT FROM AUTHOR]

Prediction of the fatigue life of piezoelectric devices and structures is of scientific and engineering significance. In this work, a phase field model for fatigue fracture in piezoelectric materials is developed by means of the Hamilton principle. Two classical phase field fracture models are unified in the present framework. A cumulative history variable is introduced to quantify the degradation of the fracture toughness under cyclic loading. The proposed model accounts for three representative electric boundary conditions on crack faces describing the fatigue fracture behaviors in different physical situations. The residual controlled staggered scheme is extended to address the fatigue fracture problems in the context of electro-elasticity. The present algorithm overcomes the convergence problem for the monolithic approach and shows higher accuracy with lower computational effort in comparison to the single-pass staggered scheme. Systematic numerical simulations are carried out in 2D and 3D cases. The effects of the electric boundary condition, external electric field, and the geometry of the crack tip on the fatigue fracture behaviors of piezoelectric solids have been discussed. The effect of the electric boundary conditions on the fatigue life varies depending on the direction of the external electric field. The present work is beneficial to assess the lifetimes of piezoelectric devices in practical applications. • A new phase field model for fatigue fracture in piezoelectric materials is developed. • Three representative electric boundary conditions are involved in the model. • Two classical phase field models are unified in the present framework. • A residual controlled staggered scheme is extended to address multi-physics problems. • Systematical simulation is performed on the fatigue behaviors. [ABSTRACT FROM AUTHOR]

Fracture analysis of piezoelectric devices and structures is of great importance in science and engineering. In the present work, a new phase field fracture model in the context of transversely isotropic electro-elasticity is developed by means of the variational method. A structural tensor is introduced in the crack surface density function to quantify the anisotropy in fracture toughness. To characterize the asymmetric fracture behavior of piezoelectric solid, the contribution of the mechanical energy is employed to drive the crack propagation. An efficient and robust staggered scheme is adopted to deal with the corresponding fracture problems, which is implemented in the commercial finite element software Abaqus. Numerical simulations are carried out to investigate the effect of the anisotropic fracture toughness, poling direction and external electrical field on the fracture behavior of the piezoelectric materials. The anisotropic fracture toughness would significantly affect the crack path and fracture load. With the help of the nonlinear regression method, a phenomenological model is proposed to predict the fracture load. The present researches may benefit the safety assessment of piezoelectric materials in practical applications. [ABSTRACT FROM AUTHOR]

Predicting the failure of piezoelectric actuators and sensors is of engineering and scientific significance. In this work, a new phase field computational framework with thermal effect is developed to characterize the fracture behavior of piezoelectric materials. The present model involves the thermo-electro-elastic coupling effect to quantify the variations of the electrical field, temperature evolution and mechanical deformation during the fracture process. The positive part of mechanical energy is solely employed as the crack driving force in order to describe the unsymmetric electrical and mechanical fracture behaviors. A robust and stable staggered algorithm, which is adopted to address multi-physics problems, is developed. Numerical calculations are carried out to show the thermal effect and the influence of the external electrical field on the fracture behaviors of piezoelectric materials. The thermal loading may promote or delay the crack propagation, while its effect on the fracture load is weak. The direction and magnitude of the external electrical fields may significantly affect the fracture loads. The present study may benefit future design of piezoelectric devices in practical engineering. • A phase field fracture model of piezoelectric solid with thermal effect is developed. • A residual controlled staggered algorithm is adopted to address the fracture problem. • Thermal effect and the influence of electric field on fracture behaviors are studied. [ABSTRACT FROM AUTHOR]

Infrared thermography techniques with thermographic data analysis have been widely applied to non-destructive tests and evaluations of subsurface defects in practical composite materials. However, the performance of these methods is still restricted by limited informative images and difficulties in feature extraction caused by inhomogeneous backgrounds and noise. In this work, a novel generative manifold learning thermography (GMLT) is proposed for defect detection and the evaluation of composites. Specifically, the spectral normalized generative adversarial networks serve as an image augmentation strategy to learn the thermal image distribution, thereby generating virtual images to enrich the dataset. Subsequently, the manifold learning method is employed for the unsupervised dimensionality reduction in all images. Finally, the partial least squares regression is presented to extract the explicit mapping of manifold learning for defect visualization. Moreover, probability density maps and quantitative metrics are proposed to evaluate and explain the obtained defect detection performance. Experimental results on carbon fiber-reinforced polymers demonstrate the superiorities of GMLT, compared with other methods. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the clinical effect of endovascular treatment on postoperative blood pressure (BP) control and kidney function of hypertensive patients with renal artery stenosis (RAS). Between January 2004 and December 2011, RAS was diagnosed in 120 renal arteries from 115 hypertensive patients. Preoperative and postoperative BPs and glomerular filtration rate (GFR) were monitored. Postoperative oral antiplatelet and antihypertensive agents were administered. Clinical follow-up was available for all patients for at least 6 months. Balloon angioplasty was performed successfully in 110 patients, and stents were deployed in 94 renal arteries from 89 patients. Hypertension was cured and lessened in 19 and 61 patients, respectively. Blood pressure was stable and worsened in 26 and 9 patients, respectively. The renal function was improved and stable in 23 patients and 57 patients, respectively. Deterioration of renal function was observed in 11 patients. Doppler ultrasound after discharge revealed 87 patent renal arteries and fixed stents in 82 patients 6 months after procedure. Balloon angioplasty and stent deployment are effective and feasible procedures for patients with RAS that help in controlling BP and improving renal function moderately. [ABSTRACT FROM AUTHOR]

To improve the classification of pig vocalization using vocal signals and improve recognition accuracy, a pig vocalization classification method based on multi-feature fusion is proposed in this study. With the typical vocalization of pigs in large-scale breeding houses as the research object, short-time energy, frequency centroid, formant frequency and first-order difference, and Mel frequency cepstral coefficient and first-order difference were extracted as the fusion features. These fusion features were improved using principal component analysis. A pig vocalization classification model with a BP neural network optimized based on the genetic algorithm was constructed. The results showed that using the improved features to recognize pig grunting, squealing, and coughing, the average recognition accuracy was 93.2%; the recognition precisions were 87.9%, 98.1%, and 92.7%, respectively, with an average of 92.9%; and the recognition recalls were 92.0%, 99.1%, and 87.4%, respectively, with an average of 92.8%, which indicated that the proposed pig vocalization classification method had good recognition precision and recall, and could provide a reference for pig vocalization information feedback and automatic recognition. [ABSTRACT FROM AUTHOR]

Hyperoside (Hyp), one of the active flavones from Rhododendron (Ericaceae), has beneficial effects against cerebrovascular disease. However, the effect of Hyp on vasodilatation has not been elucidated. To explore the effect of Hyp on vasodilatation in the cerebral basilar artery (CBA) of Sprague-Dawley (SD) rats suffering with ischaemic–reperfusion (IR) injury. Sprague-Dawley rats were randomly divided into sham, model, Hyp, Hyp + channel blocker and channel blocker groups. Hyp (50 mg/kg, IC50 = 18.3 μg/mL) and channel blocker were administered via tail vein injection 30 min before ischaemic, followed by 20 min of ischaemic and 2 h of reperfusion. The vasodilation, hyperpolarization, ELISA assay, haematoxylin–eosin (HE), Nissl staining and channel-associated proteins and qPCR were analysed. Rat CBA smooth muscle cells were isolated to detect the Ca2+ concentration and endothelial cells were isolated to detect apoptosis rate. Hyp treatment significantly ameliorated the brain damage induced by IR and evoked endothelium-dependent vasodilation rate (47.93 ± 3.09% vs. 2.99 ± 1.53%) and hyperpolarization (–8.15 ± 1.87 mV vs. −0.55 ± 0.42 mV) by increasing the expression of IP3R, PKC, transient receptor potential vanilloid channel 4 (TRPV4), IKCa and SKCa in the CBA. Moreover, Hyp administration significantly reduced the concentration of Ca2+ (49.08 ± 7.74% vs. 83.52 ± 6.93%) and apoptosis rate (11.27 ± 1.89% vs. 23.44 ± 2.19%) in CBA. Furthermore, these beneficial effects of Hyp were blocked by channel blocker. Although Hyp showed protective effect in ischaemic stroke, more clinical trial certification is needed due to the difference between animals and humans. [ABSTRACT FROM AUTHOR]

Aims: Aortic mural inflammatory damage takes a vital part in abdominal aortic aneurysm (AAA). Recently, ulinastatin (UTI) has attracted attention for its anti-inflammatory function. Our study aimed to evaluate potential influences of UTI on experimental AAA. Methods: A mouse model of AAA was induced by infusion of porcine pancreatic elastase (PPE) into the abdominal aorta. Mice were treated with UTI (50,000 U/kg/day i.p.) beginning either immediately or on the 4th day after PPE infusion, with treatment being continued until the 14th day. UTI effects were assessed by aortic diameter measurements and aortic histopathological analysis. Results: Significant and time-dependent aortic diameter enlargement persisted in the control mice from day 0. In the UTI group, aortic diameter increased, and depletion of aortic mural smooth muscle cells and elastin was significantly -attenuated. Simultaneously, mural CD68+ macrophages, CD8+ T-cell and B220+ B-cell density, as well as neoangiogenesis were suppressed by UTI. In addition, delayed UTI treatment could still effectively limit aneurysm expansion. Conclusions: UTI treatment limits the formation and growth of experimental AAA, and UTI may be a potential treatment for early AAA disease. [ABSTRACT FROM AUTHOR]

The risk of rupture, the most feared clinical consequence of abdominal aortic aneurysm, increases with the enlargement of aorta. MicroRNA-29b (miR-29b) has emerged as a key modulator of extracellular matrix (ECM) homeostasis and thereby is proposed to play a crucial role in vascular remodeling. However, agents that alter miR-29b expression are relatively inefficient in the aorta, likely due to inferior uptake. Herein we found that miR-29b was upregulated in aortic smooth muscle cells upon prostaglandin E2 (PGE2) stimulation whereas indomethacin treatment downregulated miR-29b expression. In order to obtain insight into the pathological processes associated with the vascular remodeling that accompanies aortic dilatation, we compared expression profiles of several representative ECM components in aortic walls. Notably, PGE2 induced a dramatic decline in these ECM components, which was rescued by introduction of indomethacin. In addition, COL1A1 was validated as a direct target gene of miR-29b by dual-luciferase reporter assay. In aggregate, our study suggests that PGE2 may accelerate ECM degradation through decreasing miR-29b expression. Thus those anti-inflammatory drugs that inhibit PGE2 synthesis represent an effective means of inducing an augmented profibrotic response in the aortic walls and thereby inhibiting aneurysmal expansion. [ABSTRACT FROM AUTHOR]

Simple Summary: Recurrent nasopharyngeal carcinoma is one of the major causes of death among NPC patients. However, there are no international guidelines for the treatment of patients with recurrent NPC now. In this article, we summarize past publications on clinical research and mechanistic studies related to recurrent NPC, combined with the experience and lessons learned by our institutional multidisciplinary team in the treatment of recurrent NPC. We propose an objective protocol for the treatment of recurrent NPC. Recurrent nasopharyngeal carcinoma (NPC), which occurs in 10–20% of patients with primary NPC after the initial treatment modality of intensity-modulated radiation therapy (IMRT), is one of the major causes of death among NPC patients. Patients with recurrent disease without distant metastases still have a chance to be saved, but re-treatment often carries more serious toxicities or higher risks. For this group of patients, both otolaryngologists and oncologists are committed to developing more appropriate treatment regimens that can prolong patient survival and improve survival therapy. Currently, there are no international guidelines for the treatment of patients with recurrent NPC. In this article, we summarize past publications on clinical research and mechanistic studies related to recurrent NPC, combined with the experience and lessons learned by our institutional multidisciplinary team in the treatment of recurrent NPC. We propose an objective protocol for the treatment of recurrent NPC. [ABSTRACT FROM AUTHOR]

• SDHF-GCN is the first work that models the skeleton-based graph structure with graph-based neural network in gait recognition task. • The symmetry perceptual principle enforces the dependencies between related joints and suppress the noises caused by joint estimation. • Hierarchical features can improve the expressive and discriminative power of the gait features. • SDHF-GCN renders substantial improvements over mainstream methods, especially in the coat-wearing scenario. • Silhouette-based and skeleton-based action patterns are certified to be highly complementary. Gait recognition, as an attractive task in biometrics, remains challenging due to significant intra-class changes of clothing and pose variations across different cameras. Recent approaches mainly focus on silhouette-based gait mode, which is easy to model in Convolutional Neural Networks (CNNs). Compared with silhouettes, the dynamics of skeletons essentially convey more robust information, which is invariant to view and clothing changes. Conventional approaches for modeling skeletons usually rely on hand-crafted features or traversal rules, thus resulting in limited expressive power and difficulties of generalization. In this work, we address the skeleton-based gait recognition task with a novel Symmetry-Driven Hyper Feature Graph Convolutional Network (SDHF-GCN), which goes beyond the limitations of previous approaches by automatically learning multiple dynamic patterns and hierarchical semantic features in a unified Graph Convolutional Network (GCN). This model involves three dynamic patterns: natural connection, temporal correlation and symmetric interaction, which enriches the description of dynamic patterns by exploiting symmetry perceptual principles. Furthermore, a hyper feature network is proposed to aggregate the hierarchical semantic features, including dynamic features at the high level, structured features at the intermediate level, and static features at the low level, which complement each other to enhance the discriminative ability. By integrating different patterns in the hierarchical structure, the model is able to generate versatile and discriminative representations, thus improving the recognition rate. On the CASIA-B and OUMVLP-Pose datasets, the proposed SDHF-GCN renders substantial improvements over mainstream methods, especially in the coat-wearing scenario, with superior robustness to covariate factors. [ABSTRACT FROM AUTHOR]

Widely acknowledged by experts, the inconsistency between the cells of the proton exchange membrane fuel cell stack during operation is an important cause of the fuel cell life decay. Existing studies mainly focus on qualitative analysis of the effects of operating parameters on fuel cell stack consistency. However, there is currently almost no quantitative research on predicting the voltage consistency through operating parameters with machine learning methods. To solve this problem, a three-dimensional model of proton exchange membrane fuel cell stack with five single cells is established in this paper. The Computational Fluid Dynamic (CFD) method is used to provide the source data for prediction model. After predicting the voltage consistency with several machine learning methods and comparing the accuracy through simulation data, the integrated regression method based on Gradient Boosting Decision Tree (GBDT) gets the highest score (0.896) and is proposed for quickly predicting the consistency of cell voltage through operating parameters. After verifying the GBDT method with the experimental data from the fuel cell stack of SUNRISE POWER, in which the accuracy score is 0.910, the universality and accuracy of the method is confirmed. The influencing sensitivity of each operating parameter is evaluated and the current density has the greatest influence on the predicted value, which accounts for 0.40. The prediction of voltage consistency under different combination of operating parameters can guide the optimization of structural parameters in the process of the fuel cell design and operating parameters in the process of fuel cell control. • Predict voltage consistency through operating parameters with machine learning. • Gradient Boosting Decision Tree (GBDT) method gets the highest score. • The universality and accuracy of GBDT method are verified by experiments. • The influencing sensitivity of each parameter is evaluated. [ABSTRACT FROM AUTHOR]

Nasopharyngeal carcinoma (NPC) is notorious for its aggressiveness and high metastatic potential. NPC patients with distant metastasis have a particularly poor prognosis; however, evaluating metastatic potential by expression profiles of primary tumors is challenging. This study aimed to investigate the association between activation of epidermal growth factor receptor (EGFR) signaling and NPC metastasis and the underlying mechanisms. We found an association between EGFR protein overexpression and intense EGFR immunostaining in NPC samples with advanced tumor node metastasis stage, clinical stage, and distant metastasis in NPC patients. Exogenous EGF stimulates NPC mobility and invasiveness in vitro. Activation of EGFR signaling prompted PKM2 translocation to the nucleus. Silencing either EGFR or PKM2 attenuates NPC cell aggressiveness in vitro and in vivo. Blocking EGFR signaling with cetuximab suppressed NPC cell invasiveness in vitro and metastatic potential in vivo. Comprehensive analyses of transcriptome profiles indicated that the EGFR-PKM2 axis activates a number of novel metastasis promoters, including F3, FOSL1, EPHA2, ANTXR2, and AKR1C2. Finally, we found that the metastasis-promoting function of the EGFR-PKM2 axis is dependent on nuclear PKM2 regulation of the transcription of metastasis-related genes, including FOSL1 and ANTXR2. Our study indicates that EGFR-PKM2 signaling promotes NPC cell invasion and metastasis through induction of FOSL1 and ANTXR2 and identifies EGFR as a promising biomarker for predicting the risk of distant metastasis. [ABSTRACT FROM AUTHOR]

• Turbophoresis results in particles accumulating in areas near the wall and channel center. • Turbophoresis leads to the complex distribution of radioactive decay. • The radioactivity loss due to deposition and decay was obtained for different nuclides. This paper aims at radiation monitoring and activity inversion when radionuclides are transported in duct or a pipe. The Lagrangian trajectory model was established, and a quick numerical method was used to simulate radioactive aerosols transport and radioactive decay in a wall-bounded flow. Total 12 cases were studied in the simulation according to the particle diameter and density. The dimensionless deposition velocity has been validated by comparing with Wood's predictions and the experienced gravitational settling velocity. The results show that turbophoresis has a significant effect on particle transport in the wall-bounded flow, leading to particles migration and concentrating near the wall or channel center. It will cause particles to move with different velocities in the streamwise direction, so that their residence times in channel will be complexly distributed. In addition, the gravity settling will enhance the disequilibrium of particle distribution. The activity losses are obtained in detail including particle deposition ratio and radioactive decay. One radionuclide with half-life 7 s was employed in simulation, and the activity error between the estimated and initial values is up to about 40%. The activity error decreases if the half-life becomes large. When the half-life is 7.5 and 0.5 times larger than the mean time spent by airflow through the channel if the gravity is considered or not respectively, the final activity error will be less than ±5% in the present simulation setup. [ABSTRACT FROM AUTHOR]

Multiferroic materials, which simultaneously possess piezomagnetic, piezoelectric, and electromagnetic coupling effects, have a wide range of applications in various fields. Multiferroic materials are generally brittle with low fracture toughness, and accurate prediction of the fracture behaviors of multiferroics is challenging. In this work, a phase field model for brittle fracture in multiferroic materials is developed with the help of the Hamilton principle. In light of the second law of thermodynamics, the constitutive equations are derived in the context of the phase field method. The present theoretical framework unifies two classical phase field models and four combinations of the electric and magnetic boundary conditions. The residual controlled staggered algorithm, which enjoys a higher accuracy and lower computational cost, is extended to the fracture problems in the context of magneto-electro-elasticity. Systematic numerical simulations are performed in both 2D and 3D cases. The influences of the external magnetic field, electric field, and electric and magnetic boundary conditions on fracture behaviors of multiferroic materials are studied in detail. The applied magnetic field may not only accelerate or delay the fracture, but also influence the crack path. The present work is beneficial to assess the safety of multiferroic-based devices in engineering applications. • A phase field model for brittle fracture in multiferroic materials is developed. • The AT1 and AT2 models are unified in the present phase field model. • Four magnetic and electric boundary conditions are involved in the phase field framework. • A residual controlled staggered scheme is extended to multi-physics field problems. • Systematical simulation is performed on fracture behaviors of multiferroics. [ABSTRACT FROM AUTHOR]

This paper presents a modeling approach to feature classification and environment mapping for indoor mobile robotics via a rotary ultrasonic array and fuzzy modeling. To compensate for the distance error detected by the ultrasonic sensor, a novel feature extraction approach termed "minimum distance of point" (MDP) is proposed to determine the accurate distance and location of target objects. A fuzzy model is established to recognize and classify the features of objects such as flat surfaces, corner, and cylinder. An environmental map is constructed for automated robot navigation based on this fuzzy classification, combined with a cluster algorithm and least-squares fitting. Firstly, the platform of the rotary ultrasonic array is established by using four low-cost ultrasonic sensors and a motor. Fundamental measurements, such as the distance of objects at different rotary angles and with different object materials, are carried out. Secondly, the MDP feature extraction algorithm is proposed to extract precise object locations. Compared with the conventional range of constant distance (RCD) method, the MDP method can compensate for errors in feature location and feature matching. With the data clustering algorithm, a range of ultrasonic distances is attained and used as the input dataset. The fuzzy classification model—including rules regarding data fuzzification, reasoning, and defuzzification—is established to effectively recognize and classify the object feature types. Finally, accurate environment mapping of a service robot, based on MDP and fuzzy modeling of the measurements from the ultrasonic array, is demonstrated. Experimentally, our present approach can realize environment mapping for mobile robotics with the advantages of acceptable accuracy and low cost. [ABSTRACT FROM AUTHOR]

Highlights • A stochastic method to generate turbulent fluctuations in a wall-bounded turbulent flow. • The particles deposition velocities are obtained and validated by Wood's predictions. • This method is a quick numerical method in simulating radioactive aerosols transport. Abstract Aiming at the coolant leakage monitor in the containment of a nuclear power plant, a quick numerical method of simulating radioactive aerosols transport and deposition in the near-wall region is studied in this paper. A stochastic method basing on turbulence statistics is proposed to generate anisotropic turbulent fluctuations and track particles motion separately. The model of interactions between airflow and particles is established, and the algorithm of air velocity generation is developed and validated by comparison with DNS statistical results. The longtime transport and diffusion of aerosols in a rectangle channel are simulated in this paper, particles trajectories and instantaneous distribution can be obtained. Due to the nonuniform distribution of velocity fluctuations in wall-bounded flow, the phenomenon of turbophoresis is found from the evolution of particles concentration distribution. Five kinds of particle diameters ranged from 0.1 to 10 μm and three particle densities of 500, 1000, 2500 kg/m3 are considered to compare the deposition characteristics, accordingly, the dimensionless particle relaxation time (τ +) is ranged from 10−6 to 10−1. According to statistical analysis, the dimensionless deposition velocities (V d +) versus τ+ are obtained and well agree with the Wood's predictions basically within the error scope of ±30%. It is proved that the method employed in this paper is accurate in tracking particles motion in wall-bounded flow fluids. [ABSTRACT FROM AUTHOR]

Acute lymphoblastic leukemia (ALL) affects both children and adults. However, the prognosis of the two cohorts is quite different. The present aim was to review and evaluate one potential cause of why survival is poorer in adult ALL than pediatric ALL via fluorescence in situ hybridization (FISH). Clinical significant features were analyzed in 282 ALL cases. FISH was performed to study mixed lineage leukemia (MLL) translocation and the Philadelphia (Ph) chromosome in newly diagnosed patients, and was used to detect trisomy 4 or 10 and the translocation ETS leukemia-acute myeloid leukemia 1 (TEL-AML1) fusion gene. The overall survival/event-free survival (OS/EFS) outcome of adult ALL and pediatric ALL was analyzed using Kaplan-Meier analysis. Adult ALL had a higher median leukocyte count and lower hemoglobin level than pediatric ALL. FISH revealed that Ph positivity (Ph+) was associated with the high-risk feature of older age. In pediatric ALL, trisomy 4 or 10 was present in 71/207 cases (34.3%), while the TEL-AML1 fusion gene was present in 16/207 cases (7.7%). By contrast, there were very few such positive cases in adult ALL. Survival analysis revealed that, in adult ALL, the 3-year OS and EFS rates were higher in the Ph-negative group than in the Ph+ group. Adult or pediatric ALL is an independent prognostic factor of OS. The present analysis of the clinical and biological features between adult and pediatric ALL indicates that adult ALL has a poorer prognosis than pediatric ALL based on Ph+ status and presence of trisomy 4 or 10. Ph+ ALL is an independent prognosis factor of ALL. FISH may serve an important role in the comparison of prognostic factors in adult and pediatric ALL. [ABSTRACT FROM AUTHOR]

A high-speed camera system has been used to observe the metal transfer with bead-on-plate welding. A stable pulsed streaming spray transfer was accompanied by arc jumping when the shielding gas of Ar+4%CO 2 +3%O 2 was used, but the change of metal transfer mode had a tight relationship with the bell-shaped arc rather than critical current when a mixture of Ar+13%CO 2 +3%O 2 was as shielding gas. With increasing CO 2 concentration in the shielding gas, the bright arc area and arc length decreased due to the compression effect of carbon dioxide. Weld penetration and weld width increased slightly due to the higher arc force. The ferrite content in the weld metal increased slightly with increasing CO 2 concentration in the shielding gas. [ABSTRACT FROM AUTHOR]

Abstract: The aim of this study was to clarify the prognostic role of paranasal sinus invasion in advanced NPC patients. Data of patients (n = 295) with advanced NPC (T3/T4N0‐3 M0) treated with intensity‐modulated radiation therapy were retrospectively analyzed. Staging was according to the AJCC/UICC eighth edition staging system. Overall survival (OS), local recurrence‐free survival (LRFS), distant metastasis‐free survival (DMFS), and disease‐free survival (DFS) were calculated, and differences were compared between patients with and without paranasal sinus invasion. Multivariate analysis was used to identify the independent predictors of different survival parameters. Paranasal sinus invasion was present in 126 of 295 (42.7%) patients. Sphenoid, ethmoid, maxillary, and frontal sinus involvements were present in 123 of 295 (41.7%), 95 of 295 (32.2%), 45 of 295 (15.3%), and 0 of 295 (0%), respectively. All survival parameters were significantly better in patients without paranasal sinus invasion. When paranasal sinus invasion was reclassified as T4 instead of T3, all survival rates, other than LRFS (P = 0.156), were significantly better in the new T3 patients, and differences in all survival parameters remained nonsignificant between T3 with paranasal sinus invasion and T4 without paranasal sinus invasion patients (all P > 0.05). In multivariate analysis, paranasal sinus invasion was found to be an independent negative prognostic factor for OS, DFS, and DMFS (P = 0.016, P = 0.004, and P = 0.006, respectively), but not for LRFS (P = 0.068). Paranasal sinus invasion has prognostic value in advanced NPC. It may be reasonable to classify paranasal sinus invasion as T4 stage. [ABSTRACT FROM AUTHOR]

Helium arc bead-on-plate welding has been observed using a high-speed video filming technique. Both the arc diameter and area were compressed with increasing gas flow. The arc compressed in the radial direction and stretched in length, causing a voltage increase. There was no negative-pole atomization in the direct current electrode negative (DCEN) mode, and the helium arc could tear the oxidation film on Al alloys. The broken oxidation film flowed on the molten pool under various forces. The arc shear force and arc pressure component are the dominant driving forces to tear the oxidation film. The ability of the helium arc to tear the oxidation film decreased with gas flow rate varying from 5 to 20 L/min. Penetration increased with gas flow because of the compression effect. [ABSTRACT FROM AUTHOR]

The present study retrospectively analyzed the prognostic factors of 135 patients with locally advanced nasopharyngeal carcinoma (NPC) who received intensity modulated radiation therapy between August 2008 and January 2012 at Xiangya Hospital of Central South University. Patients were staged from III-IVA according to the 7th American Joint Committee on Cancer staging system. Using Statistical Analysis System 9.3 software, the present study demonstrated that, among these 135 patients, the 5-year overall survival, the 5-year local relapse-free survival, and the 5-year disease metastasis-free survival were 84, 82, and 78%, respectively. Multivariate Cox regression analysis identified that targeted treatment [hazard ratio (95% confidence interval), 2.642 (1.001, 6.972); P=0.0497] served as an independent negative prognostic factor in locally advanced NPC. The results of immunostaining revealed that the staining intensity of the radiation-resistant group was increased compared with that of the radiation-sensitive group. These results demonstrate that a high expression of EGFR may be associated with radiation resistance, and targeted treatment may not be effective in patients with locally advanced nasopharyngeal carcinoma with low expression of EGFR. [ABSTRACT FROM AUTHOR]

Background: Brainstem dose limitations influence radiation dose reaching to tumor in the patients with locally-advanced nasopharyngeal cancer (NPC).Methods: A retrospective analysis of the prognostic value of the distance between the primary tumor and brainstem (Dbs) in 358 patients with locally-advanced NPC after intensity-modulated radiation therapy (IMRT). Receiver operating characteristic (ROC) curves were used to identify the cut-off value to analyze the impact of Dbs on tumor dose coverage and prognosis.Results: The three-year overall survival (OS), local relapse-free survival (LRFS), distant metastasis-free survival (DMFS), and disease-free survival (DFS) were 88.8 vs. 78.4% (P = 0.007), 96.5 vs. 91.1% (P = 0.018), 87.8 vs. 79.3% (P = 0.067), and 84.1 vs. 69.6% (P = 0.002) for the patients with the Dbs > 4.7 vs. ≤ 4.7 mm, respectively. ROC curves revealed Dbs (4.7 mm) combined with American Joint Committee on Cancer (AJCC) T classification had a significantly better prognostic value for OS (P < 0.05).Conclusions: Dbs (≤ 4.7 mm) is an independent negative prognostic factor for OS/LRFS/DFS and enhances the prognostic value of T classification in the patients with locally-advanced NPC. [ABSTRACT FROM AUTHOR]

Epigenetic alteration induced loss function of the transcription factor 21 (TCF21) has been associated with different types of human cancers. However, the epigenetic regulation and molecular functions of TCF21 in colorectal cancer (CRC) remain unknown. In this study, TCF21 expression levels and methylation status of its promoter region in CRC cell lines (n = 5) and CRC tissues (n = 151) as well as normal colorectal mucosa (n = 30) were assessed by RTq-PCR and methylation analysis (methylation specific PCR, MSP and bisulfite sequencing PCR, BSP), respectively. The cellular functions of TCF21 on CRC cell proliferation, apoptosis, invasion and migration were investigated in vitro. Our data revealed that TCF21 was frequently silenced by promoter hypermethylation in both tested CRC cell lines and primary CRC, and correlation analysis between methylation status and clinicopathologic parameters found that TCF21 methylation was significantly correlated with lymph node invasion (P = 0.013), while no significant correlation was found in other parameters. In addition, demethylation treatment resulted in re-expression of TCF21 in CRC cell lines, and cellular function experiments revealed that restoration of TCF21 inhibited CRC cell proliferation, promoted apoptosis and suppressed cell invasion and migration, suggesting that TCF21 may function as a tumor suppressor gene, which is downregulated through promoter hypermethylation in CRC development. [ABSTRACT FROM AUTHOR]

Ultrasonic wedge bonding is an important step in the manufacture of integrated circuits (ICs). Due to the small size of IC chips, methods for maintaining the reliability of wedge bonding are necessary to avoid large amounts of material waste and low production efficiency. Wire loss or wire error is a typical bonding failure in the wire bond process. This paper presents a monitoring method that detects aluminum wire loss or wire error during the aluminum ultrasonic wedge bonding process. During the bonding process, the impedance from the ultrasonic transducer is measured, and then compared with a predetermined threshold to assess whether the wire has been lost. To improve monitoring accuracy and sensitivity, the Kalman filter with a forgetting factor is introduced during the ultrasonic wire bonding, and the influence of the forgetting factor on the rate of false positives and the speed of error detection is investigated. It is found that the forgetting factor can determine the rate of false positives and monitoring sensitivity. By optimizing the forgetting factor, the rate of false positives can be lowered to below 0.05%, and wire loss can be detected within five bonding times after the loss occurred. This novel method shows good monitoring accuracy and can be used in aluminum wedge bonding. [ABSTRACT FROM AUTHOR]

In this study, 8-iodocoumarin derivatives underwent a direct Stille cross-coupling reaction with several organotin compounds in the presence of a catalytic amount of Pd(PPh3)4 in DMF at 80 °C. The cross-coupling reaction proceeded smoothly under mild conditions and permitted the formation of 8-allyl or 8-prenylcoumarin compounds in good yields. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A COSMIC-1/FORMOSAT-3 (Constellation Observing System for Meteorology, Ionosphere, and Climate-1 and Formosa Satellite Mission 3) follow-on mission, COSMIC-2/FORMOSAT-7, had been successfully launched into low-inclination orbits on 25 June 2019. COSMIC-2 has a significantly increased Signal-to-Noise ratio (SNR) compared to other Radio Occultation (RO) missions. This study summarized the initial assessment of COSMIC-2 data quality conducted by the NOAA (National Oceanic and Atmospheric Administration) Center for Satellite Applications and Research (STAR). We use validated data from other RO missions to quantify the stability of COSMIC-2. In addition, we use the Vaisala RS41 radiosonde observations to assess the accuracy and uncertainty of the COSMIC-2 neutral atmospheric profiles. RS41 is currently the most accurate radiosonde observation system. The COSMIC-2 SNR ranges from 200 v/v to about 2800 v/v. To see if the high SNR COSMIC-2 signals lead to better retrieval results, we separate the COSMIC-2–RS41 comparisons into different SNR groups (i.e., 0–500 v/v group, 500–1000 v/v group, 1000–1500 v/v group, 1500–2000 v/v group, and >2000 v/v group). In general, the COSMIC-2 data quality in terms of stability, precision, accuracy, and uncertainty of the accuracy is very compatible with those from COSMIC-1. Results show that the mean COSMIC-2–RS41 water vapor difference from surface to 5 km altitude for each SNR groups are equal to −1.34 g/kg (0–500 v/v), −1.17 g/kg (500–1000 v/v), −1.33 g/kg (1000–1500 v/v), −0.93 g/kg (1500–2000 v/v), and −1.52 g/kg (>2000 v/v). Except for the >2000 v/v group, the high SNR measurements from COSMIC-2 seem to improve the mean water vapor difference for the higher SNR group slightly (especially for the 1500–2000 v/v group) comparing with those from lower SNR groups. [ABSTRACT FROM AUTHOR]