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This article is aimed at condition monitoring and fault identification for Internet of Things (IoT) devices, and proposes a multivariate statistical process control scheme. The new method aims to detect sparse mean shifts using spatial rank and an improved adaptive elastic net algorithm, which can monitor the high-dimension data stream collected by IoT devices and pinpoint faulty variables. The new method is also applicable in the presence of a non-normal distribution and insufficient reference samples. Numerical simulations verify that the proposed method has clear advantages over existing methods. The case of wind turbines shows that the method can be applied to real-time monitoring and diagnosis of real IoT devices, which could provide valuable diagnosis of root cause and optimize subsequent maintenance strategies. [ABSTRACT FROM AUTHOR]

To explore the enhancement mechanism of CFRP overwrap in the aluminum-CFRP square hybrid, hybrid tubes with different braided angles were investigated both experimentally and numerically. Hybrid tube of 30 degrees had severe CFRP layers splitting damage in the tube corner. As the braided angle up to 60 degrees, CFRP layers with high transverse resistance force compressed the aluminum tube and caused it to fold inward; This led to the hybrid tube failing in a distinct inward eccentric fold deformation pattern and had an obvious energy absorption improvement in its inner aluminum tube due to its increase in the corner deformation. [ABSTRACT FROM AUTHOR]

A numerical model of the equivalent time conversion to DC stressing for electromigration failures under various current waveforms is proposed based on the vacancy diffusion and damage healing theory. The Joule heating effect and the intrinsic stress-induced voiding are included in the calculation of interconnect reliability. The simulation results show that the cumulative lifetimes are strongly affected by current frequency and vacancy lifetime and a frequency shift to the right occurs for small vacancy lifetimes under AC stressing. For pulsed-DC stressing, the temperature rise dependent on the current frequency dominates the interconnect reliability. The average temperature rise due to Joule heating is reduced by two times when the frequency is larger than approximately the reciprocal of the thermal time of interconnect structures. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the effects and mechanisms of hematopoietic-substrate-1-associated protein X-1 (HAX-1) on liver cancer cells. Information on HAX-1 from liver cancer patients was analyzed by the Cancer Genome Atlas (TCGA) program. Cell migration and invasion abilities were respectively tested by scratch assay and transwell assay. Tube formation assay was applied to detect angiogenesis protein and mRNA was determined using quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot. We found that the median month survival of HAX-1 overexpressing liver cancer patients was shorter than that of HAX-1 normal liver cancer patients. HAX-1 was overexpressed in liver cancer tissues and cells, and HAX-1 overexpression promoted the liver cancer cells growth, migration, and invasion, whereas silencing HAX-1 produced the opposite results. Inhibition of Akt by LY294002 reversed the migration and invasion abilities of liver cancer cells, and inhibited the ability of cells growth and angiogenesis. Silencing PIK3CA enhanced the inhibitory effects of HAX-1 silencing on the viability, migration, and invasion of liver cancer cells. HAX-1 affected liver cancer cells metastasis and angiogenesis by affecting Akt phosphorylation and FOXO3A expression. [ABSTRACT FROM AUTHOR]

CdS quantum dots (QDs) and N719/QDs cosensitized solar cells based on ZnO nanorod arrays as photoanodes were successfully constructed. The influence of deposition times for CdS QDs on photovoltaic performance of ZnO/CdS photoanodes has been studied. The optimized photovoltaic performance was obtained from the device of the ZnO/CdS(10) electrode, with aVOCof 0.52 V, aJSCof 5.07 mA cm−2, aFFof 18.36, and an η of 0.48%. The cosensitized solar cell exhibited 35% enhancement in power conversion efficiency compared with the device sensitized by CdS QDs only. [ABSTRACT FROM PUBLISHER]

Abstract\nHIGHLIGHTSCFRP laminates are commonly used in aircraft structures due to their high structural efficiency. The phenomenon-based failures of CFRP laminates have poor predictability for the complex failure process with buckling and matrix fractures. This work carried out seven shear tests of CFRP laminates. It also attempts to reveal its failure characteristic points by directly modeling the measured strain data based on the relative deformation distribution catastrophe. The failure characteristic points are revealed by constructing the stressing state modes/parameters and applying the clustering analysis criterion, whose accuracy can be verified by comparing the shear failure characteristic points of nondestructive/impacted CFRP laminates.Conduct 7 nondestructive/impacted CFRP laminates shear tests.Construct the modes and characteristic parameters characterizing the shear-stressing state of CFRP laminates.Applying clustering analysis criterion to reveal the characteristic loads of CFRP laminates.Verify the accuracy and robustness of the characteristic loads. [ABSTRACT FROM AUTHOR]

As the number of patients increases, physicians are dealing with more and more cases of degenerative spine pathologies on a daily basis. To reduce the workload of healthcare professionals, we propose a modified Swin-UNet network model. Firstly, the Swin Transformer Blocks are improved using a residual post-normalization and scaling cosine attention mechanism, which makes the training process of the model more stable and improves the accuracy. Secondly, we use the log-space continuous position biasing method instead of the bicubic interpolation position biasing method. This method solves the problem of performance loss caused by the large difference between the resolution of the pretraining image and the resolution of the spine image. Finally, we introduce a segmentation smooth module (SSM) at the decoder stage. The SSM effectively reduces redundancy, and enhances the segmentation edge processing to improve the model’s segmentation accuracy. To validate the proposed method, we conducted experiments on a real dataset provided by hospitals. The average segmentation accuracy is no less than 95%. The experimental results demonstrate the superiority of the proposed method over the original model and other models of the same type in segmenting the spinous processes of the vertebrae and the posterior arch of the spine. [ABSTRACT FROM AUTHOR]

This article presents a two-step iterative method that uses u – P formulation to study a Degasperis-Procesi (DP) equation, with which the DP equation is decomposed into the nonlinear advection equation and the Helmholtz equation. The first-order derivative terms in the advection equation are approximated by an Optimized Compact Reconstruction Weighted Essentially Non-Oscillatory (OCRWENO) scheme that reduces dispersion and dissipation errors and suppresses oscillation near discontinuities. Besides, high-order symplectic Runge-Kutta scheme is used for time marching. A rigorous analysis of the dispersion and dissipation errors are provided for the OCRWENO scheme. Single smooth soliton solution is investigated to check the accuracy and the order of the proposed method. Peakon, peakon-peakon, peakon-antipeakon and shockpeakon solutions of the DP equation are then predicted. Finally, wave breaking phenomena of smoothed initial condition from the DP equation are addressed. In addition, two conservative quantities associated with the bi-Hamiltonian form of the DP equation are calculated to demonstrate capabilities of the present method. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the prevalence and characteristics of imipenem-resistant Acinetobacter baumanni isolated from surgical wards in a university hospital, China. A total of 143 non-duplicate A. baumannii were isolated from 517 inpatients in surgery intensive care units (ICUs), burn wards, and general surgery wards. Of these, 102 isolates of A. baumannii (71.3%) were resistant to imipenem. Among imipenem-resistant isolates, all isolates were resistant to almost all antimicrobial agents except polymyxin E, all isolates were positive for blaOXA-23 and bla OXA-51 in addition to IS Aba1, 52 (51%) were positive for blaOXA-58 , 8 (7.8%) contained blaVIM-2 , which co-harbored with blaOXA-58 . Molecular typing revealed the presence of three clones among imipenem-resistant isolates. This study confirmed that A. baumannii strains harboring OXA or VIM type β-lactamases are widely distributed throughout the surgery wards. The data demonstrate that there was a high prevalence of imipenem-resistant A. baumannii infection in the region. [ABSTRACT FROM AUTHOR]

An introduction is presented in which the editor discusses articles in the issue on topics including classroom use of clickers; impact of international trips on students to gain cross-cultural intelligence; and globalization.

Spatial variability of tensile strength, widely existing in concrete gravity dams due to the influence of long construction period and heterogeneous construction quality, has a profound impact on the nonlinear behaviour of structures. In this paper, a method to simulate the random field of the tensile strength of concrete gravity dams based on the random field theory is proposed. A typical non-overflow dam section of the Guandi gravity dam is taken as an example, artificial seismic waves with similar response spectra and natural seismic waves with different magnitudes are selected for the comparative analysis. Based on the concrete damage plasticity (CDP) model and incremental dynamic analysis (IDA) method, the damage characteristics, failure modes, probability density evolution processes, and fragility curves obtained from gravity dams with homogenous and random fields of tensile strength are compared with each other. The differences among waves and realisations of random fields are also investigated. It is seen that the spatial variability of tensile strength aggravates the damage degree, decreases the continuity of local damaged areas, and increased the failure probability of global dams. It reveals that the random characteristics affect the dams' nonlinear behaviour directly. [ABSTRACT FROM AUTHOR]

Background: The aim was to evaluate the effect of transient glare on shape discrimination threshold (SDT) in myopic adults.Methods: A total of 162 myopic subjects were enrolled. Of these, 121 had low to mid myopia (-1.00 D to -6.00 D) and 41 had high myopia (-6.13 D to -10.25 D). All subjects had corrected visual acuity of 6/6 or better, and only data for the right eye were included in the study. SDTs were measured with circular D4 (fourth derivative of Gaussian) radial frequency patterns with a radial frequency of four, peak spatial frequency of three cpds, and mean radius of 1.5 degrees. SDTs were measured under two conditions, with and without the presence of transient glare while the stimulus was displayed (duration = 500 ms).Results: Without transient glare, SDTs were not different between the low-mid (23.84 ± 6.02 arcsec) and high myopia groups (25.17 ± 5.98 arcsec, p = 0.16, Mann-Whitney test). With transient glare, SDTs in all subjects became significantly higher (p < 0.001, Wilcoxon signed-rank test). SDTs in the high myopia group (55.53 ± 18.59 arcsec) became significantly higher than those in the low to mid myopia group (47.55 ± 15.06 arcsec, p = 0.014, Mann-Whitney test). The increments were significantly higher in the high myopia group (28.94 arcsec versus 20.88 arcsec, p = 0.031, Mann-Whitney test). Multiple regression showed that SDTs with glare were significantly associated with SDTs without glare (p < 0.001) and the presence of high myopia (p = 0.015).Conclusions: Transient glare significantly increased SDTs in all myopic subjects, with the increment in subjects with high myopia being significantly larger than those in subjects with low to mid myopia. [ABSTRACT FROM AUTHOR]

Two functional polyurethanes (P1 and P2) bearing a large π electron conjugated chromophoric pendant were synthesized and characterized by FT-IR, 1H-NMR and UV-Vis absorption spectra. Their optical limiting properties were evaluated. The results show that P1 and P2 show novel optical limiting properties, which are assigned to a long π electron conjugated chromophoric pendant. It was found that their optical limiting properties were affected simultaneously by solution concentration and P2 displays a better optical limiting property than P1 at the same solution transmittance, although that P1 has larger χ(3) (4.28×10-11 esu) than P2 (0.87×10-11 esu), and their optical limiting mechanism is investigated. [ABSTRACT FROM AUTHOR]