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The prediction of remaining useful life (RUL) is a critical component of prognostic and health management for industrial systems. In recent decades, there has been a surge of interest in RUL prediction based on degradation data of a well‐defined degradation index (DI). However, in many real‐world applications, the DI may not be readily available and must be constructed from complex source data, rendering many existing methods inapplicable. Motivated by multivariate sensor data from industrial induction motors, this paper proposes a novel prognostic framework that develops a nonlinear DI, serving as an ensemble of representative features, and employs a similarity‐based method for RUL prediction. The proposed framework enables online prediction of RUL by dynamically updating information from the in‐service unit. Simulation studies and a case study on three‐phase industrial induction motors demonstrate that the proposed framework can effectively extract reliability information from various channels and predict RUL with high accuracy. [ABSTRACT FROM AUTHOR]

In the high-precision optoelectronic tracking system (OTS) based on a charge-coupled device (CCD), the boresight error extracted from the tracking image contains an undeniable delay, which directly limits the control bandwidth of visual tracking. High bandwidth means high response speed and tracking accuracy. Generally, a model-based delay compensation control method called the Smith predictor is utilized to separate time delay from the closed loop to promote the control bandwidth. However, due to the existence of errors between the established model and the real object, the improvement in the bandwidth is still limited to ensure system stability, resulting in insufficient tracking performance. In this paper, to solve the problem, a Smith predictor modified with pseudo feedforward control for the OTS is proposed. The experimental results demonstrate that the proposed method achieves significant improvements in tracking performance, reducing the maximum residual error at 1 Hz from 365 arcseconds (using the classic Smith predictor) to 283 arcseconds, a 22.5% improvement. Across the main frequency band (0.2 Hz to 2 Hz), the residual errors were consistently lower using the proposed method. [ABSTRACT FROM AUTHOR]

The development of carbon dioxide (CO2) separation technology is crucial for mitigating global climate change and promoting sustainable development. In this study, we successfully synthesized an array of cross‐linked poly(vinyl alcohol) (PVA) membranes, xALD‐PEG‐ALD‐c‐PVA, with enhanced CO2/N2 separation performance by employing dialdehyde polyethylene glycol (ALD‐PEG‐ALD) as a cross‐linker. The formation of the cross‐linked network structure not only inhibits the crystallization of PVA but also disrupts hydrogen bonding and thus increases fractional free volume of PVA chains. Under the synergistic effect of these multiple factors, the cross‐linked PVA membranes exhibit a significantly improved CO2 permeability. Moreover, they maintain high CO2/N2 selectivity, attributing to the CO2‐philic characteristic of ethylene oxide groups in the cross‐linked structure. At the ALD‐PEG‐ALD content of 1.6 mmol g−1, the xALD‐PEG‐ALD‐c‐PVA membrane demonstrates a CO2 permeability of 41.4 barrer and a CO2/N2 selectivity of 57.4 at 2 bar and 25°C. Furthermore, compared with the pristine PVA membrane, xALD‐PEG‐ALD‐c‐PVA membranes manifest superior mechanical properties and outstanding separation performance for a CO2/N2 (15/85, vol%) gas mixture. The excellent combination of permeability and selectivity makes xALD‐PEG‐ALD‐c‐PVA membranes highly promising for various CO2 separation applications. [ABSTRACT FROM AUTHOR]

Purpose: Breast cancer is the most common cancer type worldwide, with its survivors often experiencing physical and psychosocial health problems. Wearable device use is an innovative and effective way to promote physical activity and improve health‐related outcomes in breast cancer survivors; however, the current evidence is unclear. We aimed to determine the effects of wearable devices on physical activity and health‐related outcomes in breast cancer survivors. Methods: PubMed, Embase, Web of Science, and Cochrane Library databases were searched to identify eligible studies from inception to September 2022. Additional relevant studies were obtained from the reference lists of the identified studies. Two reviewers independently screened the eligible studies, appraised the risk of bias, and extracted the data. Meta‐analysis was conducted using Review Manager version 5.3. Findings: Sixteen randomized controlled trials were included. Physical activity tracking and pedometer‐based interventions improved moderate‐intensity physical activity (standardized mean difference [SMD] = 0.32, 95% confidence interval [CI]: 0.17–0.46, p < 0.0001), moderate‐to‐vigorous physical activity (SMD = 0.85, 95%CI: 0.38–1.32, p = 0.0004), total physical activity (SMD = 0.51, 95%CI: 0.12–0.90, p = 0.01), quality of life (SMD = 0.17, 95%CI: 0.03–0.31, p = 0.01), physical function (SMD = 0.21, 95%CI: 0.04–0.38, p = 0.02), and mood state profiles (SMD = −0.58, 95%CI: −1.13 to 0.02, p = 0.04) in breast cancer survivors. However, the effects of low‐intensity physical activity, vigorous‐intensity physical activity, fatigue, anxiety, depression, and sleep quality could not be ascertained. Conclusions: Physical activity tracking and pedometer‐based interventions were effective in increasing physical activity and improving health‐related outcomes in breast cancer survivors. Implications for nursing practice: This review offers availability of credible evidence supporting the potential usefulness and effectiveness of wearable physical activity trackers on physical activity and health‐related outcomes in breast cancer survivors. [ABSTRACT FROM AUTHOR]

Ciprofloxacin (CIP, C17H18FN3O3), one of the main pollution sources detected in water, has raised intense issues. In order to resolve this issue, it is essential to achieve efficient degradation of CIP under visible light. Herein, a set of two-dimensional composites MoS2/Bi2MoO6 were constructed, and proved via XRD, FT-IR, SEM, TEM, and XPS, respectively. In addition, the results recorded that when the optimized composites 0.5%-MoS2/Bi2MoO6 were applied, the degradation rate of CIP was up to 91% at 120 min under the irradiation of visible light (> 395 nm) which was superior to that of the pure MoS2 or Bi2MoO6. UV–Vis DRS, photocurrent, and electrical impedance analyses indicate that the outperformance of 0.5%-MoS2/Bi2MoO6 is due to the optimized band gap and specific surface area. More importantly, a photocatalytic mechanism was proposed based on the analysis of GC–MS (according to the references (Dang et al. in Chem Eng J 422(15):130103, 2021; Zhu et al. in Environ Sci Pollut Res Int 30(11):28874–28888, 2022)) and active species. The result was manifest: CIP was degraded progressively under the attack of photocatalytically generated h+,.O2−. This work opens up a category for the construction of efficient Bi2MoO6-based composites and proposes a hypothetical mechanism and pathway for CIP degradation. [ABSTRACT FROM AUTHOR]

Searching for a stable and efficient photocatalyst still presents a variety of challenges, when photocatalytic technology is widely used today. In this paper, oxygen-vacancy BiOCl with different masses was loaded on Bi4O5Br2 nanosheets by a simple two-step method. The UV–Dis spectrum showed that the absorption range of the complex to visible light was larger than that of the two pure substances. In addition, the PL, i – t and EIS characterization prove that the formation of heterogeneous interface between the two materials accelerated the charge transfer in the semiconductor, eventually making photocatalytic efficiency significantly increased. The results showed that the 1 wt.% Ov-BOC@BOB has the best degradation performance, which was seven and four times than that of Ov-BOC and BOB within 120 min, respectively. Free radical capture experiment further confirmed that the charge transfer between oxygen-vacancy BiOCl and Bi4O5Br2 conforms to the Z-type transfer mechanism, such a charge-transfer mechanism would leave behind strongly reducing electrons and strongly oxidizing holes, respectively. The degradation rate of ciprofloxacin (CIP) was not significantly reduced after five cycles of experiments, indicating that the compound had good stability. This study provides a feasible idea for exploring stable and efficient photocatalysts. Z-type heterojunction of BiOCl@Bi4O5Br2 with oxygen vacancy was prepared. The construction of heterostructures facilitates the separation and transfer of photogenerated charges. Free radical capture experiment further confirmed that the charge transfer between oxygen-vacancy BiOCl and Bi4O5Br2 conforms to the Z-type transfer mechanism. [ABSTRACT FROM AUTHOR]

The electronic structure has a profound effect on the performance of photocatalyst. In this study, the electronic structure of Bi2WO6 is calculated with density functional theory (DFT). The CoWO4@Bi2WO6 Z-scheme heterojunction was prepared by one-step hydrothermal method. XRD, XPS, SEM, and TEM were used to demonstrate the successful preparation of the composites. Ciprofloxacin was used to test the performance of the catalysts. The results showed that the 1:5 CBWO has the best degradation performance, which was 5 and 9 times than that of BWO and CWO within 120 min, respectively. The intervention of DFT theory provides a reference for the selection of loading material and one-step hydrothermal method can save energy and produce high yield of materials. Therefore, this study has a good guiding significance for the modification of Bi2WO6 and other photocatalytic materials in the future. [ABSTRACT FROM AUTHOR]

Bi/Bi4O5Br2 composite photocatalysts with different loading were prepared by ethylene glycol reduction method. The successful construction of the composite was confirmed by X-ray diffraction, Fourier transform infrared, scanning electron microscope, photoluminescence, UV–Vis diffuse reflection spectroscopy, and X-ray photoelectron spectroscopy. The prepared Bi/Bi4O5Br2 composite can degrade the colored dye RhB and the colorless substance BPA under simulated visible light. The catalytic activity of the composite is obviously improved compared with that of the pure substance, and the photocatalytic performance of 5% loading of composite sample is the best. Through the experiments of photoluminescence spectrum and fluorescence decay curve, it is confirmed that the photo-generated carrier separation efficiency of 5% loading of composite sample is the highest. Radical trapping experiments show that h+ plays a major role. The improvement of photocatalytic activity of the composite is attributed to the plasmon resonance effect of Bi, which promotes the transfer and separation of semiconductor interface charge. The composite material has good cycle stability, which provides a research idea for the photocatalytic treatment of wastewater. [ABSTRACT FROM AUTHOR]

The gamma distribution is one of the most important parametric models in probability theory and statistics. Although a multitude of studies have theoretically investigated the properties of the gamma distribution in the literature, there is still a serious lack of tailored statistical tools to facilitate its practical applications. To fill the gap, this paper develops a comprehensive R package for the gamma distribution. In specific, the R package focuses on the following three important tasks: generate the gamma random variables, estimate the model parameters, and construct statistical limits, including confidence limits, prediction limits, and tolerance limits based on the gamma random variables. The proposed package encompasses the state-of-the-art methods of the gamma distribution in the literature and its usage is illustrated by a real application. [ABSTRACT FROM AUTHOR]

V‐doped WO3 microspheres composed of nanorods radially grown from the center were fabricated via a simple hydrothermal method. The as‐obtained products were characterized by several techniques such as X‐ray powder diffraction (XRD), energy dispersive spectrometer (EDS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), Raman spectrum, and Brunauer–Emmett–Teller (BET). It was found that V atoms were incorporated inside the hexagonal WO3 lattice. On the basis of time‐dependent experiments, the formation mechanism for the as‐prepared V‐doped WO3 micro‐nanostructures was discussed. In addition, the catalytic properties of the synthesized material on the thermal decomposition of ammonium perchlorate (AP) were evaluated by thermal gravimetric and differential thermal analysis (TG/DTA), which showed the thermal decomposition temperatures of AP in the presence of 1, 2, and 4 wt% of V‐doped WO3 micro‐nanostructures were reduced to 399, 393, and 380°C, respectively. [ABSTRACT FROM AUTHOR]

Abstract: This study aims to explore the value of real-time strain elastography (RTE) and contrast-enhanced ultrasonography (CEUS) in the diagnosis of breast BI-RADS 4 lesions. It collected 85 cases (totaling 85 lesions) diagnosed with breast BI-RADS 4 through routine ultrasound from October 2020 to December 2022 in Huangshan City People's Hospital. All lesions underwent RTE and CEUS examination before surgery, and the ImageJ software was used to measure the periphery of lesion images in the enhancement peak mode and grayscale mode to calculate the contrast-enhanced ultrasound area ratio. The diagnostic capabilities of single-modal and multimodal ultrasound examination for the malignancy of breast BI-RADS 4 lesions were compared using the receiver operating characteristic curve; the Spearman correlation analysis was adopted to evaluate the correlation between multimodal ultrasound and CEUS area ratio. As a result, among the 85 lesions, 51 were benign, and 34 were malignant. The areas under the curve (AUCs) of routine ultrasound (US), US + RTE, US + CEUS, and US + RTE + CEUS were 0.816, 0.928, 0.953, and 0.967, respectively, with the combined method showing a higher AUC than the single application. The AUC of the CEUS area ratio diagnosing breast lesions was 0.888. There was a strong positive correlation (r = 0.819, P < 0.001) between the diagnostic performance of US + RTE + CEUS and the CEUS area ratio. In conclusion, based on routine ultrasound, the combination of RTE and CEUS can further improve the differential diagnosis of benign and malignant lesions in breast BI-RADS 4., Competing Interests: Competing interests: All of the authors had no any personal, financial, commercial, or academic conflicts of interest separately., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)