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Fetal abdominal subcutaneous soft tissue thickness (FASSTT) is a key indicator in evaluating fetal growth, development, and nutritional status. Currently, manual measurement in FASSTT faces the problems of difficulty in positioning, time consumption, and inaccurate measurement. Therefore, this article proposes an automatic measurement scheme for FASSTT. Firstly, a U‐shaped attention network VGG‐SeUnet is proposed to automatically segment the subcutaneous soft tissue area of the fetal abdomen. Secondly, based on the segmentation results, a morphological method is proposed to obtain FASSTT. Specifically, the segmentation network uses VGG16 as the encoder and connects the decoder through jump connections for multi‐scale fusion. We introduce channel attention to jump connections, which enables the model to select key channels for feature fusion. At the same time, the model uses the proposed DF_Loss function for training to solve the problem of sample imbalance. Based on the segmentation results, a morphological distance transformation algorithm is proposed to obtain FASSTT by drawing the maximum inscribed circle and calculating its diameter. The method is evaluated on a fetal abdominal circumference ultrasound dataset containing 135 samples. The DSC, mIOU, mPA, Precision and Recall of the segmentation experiments reache 88.9%, 81.02%, 90.44%, 86.38%, and 90.44% respectively. The difference between FASSTT's result from that provided by radiologist is 0.0615 cm in Average Error (AVE) and 0.081 cm in Root Mean Square Error (RMSE). The overall performance of this algorithm is superior to existing methods with excellent performance, and the measurement error is less than 1 millimeter. This result proves that the proposed scheme in this paper can achieve automated measurement of FASSTT and assist doctors in subsequent evaluation of fetal development and nutritional status. [ABSTRACT FROM AUTHOR]

Laser cladding is a new technology to fabricate a coating on the surface of a metal substrate. The properties on copper substrates are usually not very good due to the high thermal conductivity and reflectivity. The appropriate preheating temperature is helpful to fabricate coatings with good quality and properties, especially for copper substrates. In order to investigate the effect of different preheating temperatures, four coatings with different preheating temperatures (100, 200, 300 and 400 °C) were fabricated via a laser on a copper substrate. The microstructures and properties of four coatings were investigated using SEM, XRD, EDS, a Vickers microhardness meter, a wear tester and an electrochemical workstation. The results show that the elements from Ni-based alloy powder were uniformly distributed among the binding region, which obtained a good metallurgical bonding. The microstructure was mainly composited of cellular, dendrite and plane crystals, and the main reinforced phases were γ (Fe, Ni), Cr0.09Fe0.7Ni0.21, WC and Ni3B. The values of average microhardness of the four coatings were 614.3, 941.6, 668.1 and 663.1 HV0.5, respectively. The wear rates of the four coatings were 9.7, 4.9, 12.5 and 13.3 × 10−5 mm3·N−1·m−1, respectively, which were less than that of the copper substrate (4.3 × 10−3 mm3·N−1·m−1). The decrease in wear rate was due to the existence of the reinforced phases, such as WC, Ni3B, M7C3 (M=Fe, Cr) and Cr0.09Fe0.7Ni0.21. The fine crystals in the coating preheated at 200 °C also improved the wear resistance. Additionally, the minimum values of corrosion current density were 3.26 × 10−5, 2.34 × 10−7, 4.02 × 10−6 and 4.21 × 10−6 mA·mm−2, respectively. It can be seen that the coating preheated at 200 °C had higher microhardness, lower wear rates and better corrosion resistance due to the existence of reinforced phases and fine and uniform crystals. [ABSTRACT FROM AUTHOR]

The optimal surgical intervention for lateral patellar instability remains a topic of controversy despite satisfactory clinical outcomes and low re‐dislocation rates reported in numerous studies following medial patellofemoral ligament reconstruction (MPFLR) with and without tibial tubercle transfer (TTT). The purpose of this systematic review and meta‐analysis is to investigate the hypothesis that combining MPFLR with TTT provides reduced complication rates and improved clinical outcomes to isolated MPFLR in patients with lateral patellar instability. We conducted a comprehensive systematic review and meta‐analysis of comparative trials involving MPFLR with and without TTT, sourcing data from PubMed, the Cochrane Library, Embase, and Web of Science. The primary clinical outcomes analyzed included the Kujala score, the Lysholm score, complication rates, and the Caton–Deschamps index (CDI). Random or fixed effects were used for the meta‐analysis. Postoperatively, there were no significant differences observed in the Kujala and Lysholm scores between MPFLR and MPFLR + TTT (p = 0.053). At the final follow‐up, the CDI had decreased 0.015 (95% CI −0.044, 0.013; p = 0.289) points in the MPFLR group, with no statistical significance. In contrast, the MPFLR + TTT group demonstrated a significant decrease of 0.207 (95% CI −0.240, −0.174; p = 0.000) points in CDI. Notably, the complication rate was higher in the MPFLR + TTT group compared to the MPFLR‐only group (RR = 2.472; 95% CI 1.638, 3.731; p = 0.000). Both MPFLR and MPFLR + TTT procedures yield significant improvements in the Kujala and Lysholm scores. However, the MPFLR + TTT approach results in an apparent improvement in CDI and corrects patellar maltracking, particularly in cases involving high tibial tuberosity‐trochlear groove (TT‐TG) (>20 mm) or patella alta (CDI > 1.2), while MPFLR alone cannot. It is essential to consider the higher complication rate of MPFLR + TTT, which suggests that MPFLR alone may be sufficient for patients without high TT‐TG or patella alta. [ABSTRACT FROM AUTHOR]

The performance of bearings plays a pivotal role in determining the dependability and security of rotating machinery. In intricate systems demanding exceptional reliability and safety, the ability to accurately forecast fault occurrences during operation holds profound significance. Such predictions serve as invaluable guides for crafting well-considered reliability strategies and executing maintenance practices aimed at enhancing reliability. In the real operational life of bearings, fault information often gets submerged within the noise. Furthermore, employing Long Short-Term Memory (LSTM) neural networks for time series prediction necessitates the configuration of appropriate parameters. Manual parameter selection is often a time-consuming process and demands substantial prior knowledge. In order to ensure the reliability of bearing operation, this article investigates the application of three advanced techniques—Maximum Correlation Kurtosis Deconvolution (MCKD), Multi-Scale Permutation Entropy (MPE), and Long Short-Term Memory (LSTM) recurrent neural networks—for the prediction of the remaining useful life (RUL) of rolling bearings. The improved sparrow search algorithm (ISSA) is employed for configuring parameters in the Long Short-Term Memory (LSTM) network. Each technique's principles, methodologies, and applications are comprehensively reviewed, offering insights into their respective strengths and limitations. Case studies and experimental evaluations are presented to assess their performance in RUL prediction. Findings reveal that MCKD enhances fault signatures, MPE captures complexity, and LSTM excels in modeling temporal patterns. The root mean square error of the prediction results is 0.007. The fusion of these techniques offers a comprehensive approach to RUL prediction, leveraging their unique attributes for more accurate and reliable predictions. [ABSTRACT FROM AUTHOR]

Background: Osteoarthritis (OA) is a common disease that causes joint pain and disability. Stem cell therapy is emerging as a promising treatment for OA. Purpose: To evaluate the ability of peripheral blood–derived mesenchymal stem cells (PBMSCs) combined with donor-matched platelet-rich plasma (PRP) to treat OA in a rabbit model. Study Design: Controlled laboratory study. Methods: PBMSCs and donor-matched PRP were isolated and prepared from the same rabbit. PBMSCs were treated with serum-free medium, fetal bovine serum, and PRP; a series of PBMSC behaviors, including proliferation, migration, and adhesion, were compared among groups. The ability of PBMSCs or PRP alone and PBMSCs+PRP to protect chondrocytes against proinflammatory cytokine (interleukin 1β [IL-1β]) treatment was compared by analyzing reactive oxygen species (ROS)–scavenging ability and apoptosis. Real-time quantitative polymerase chain reaction and immunofluorescence were used to investigate the expression of extracellular matrix (ECM) metabolism genes and proteins, and Western blotting was used to explore the potential mechanism of the corresponding signaling pathway. In vivo, the effect of PBMSCs+PRP on cartilage and inflammation of the synovium was observed in a surgery-induced OA rabbit model via gross observation, histological and immunohistochemical staining, and enzyme-linked immunosorbent assay. Results: Proliferation, migration, and adhesion ability were enhanced in PBMSCs treated with PRP. Moreover, compared with either PBMSCs or PRP alone, PBMSCs+PRP enhanced ROS-scavenging ability and inhibited apoptosis in IL-1β–treated chondrocytes. PBMSCs+PRP also reversed the IL-1β–induced degradation of collagen type 2 and aggrecan and increased expression of matrix metalloproteinase 13, and this effect was related to increased expression of ECM synthesis and decreased expression of degradation and inflammatory genes and proteins. Mechanistically, PBMSCs+PRP reduced the phosphorylation of inhibitor of nuclear factor-κBα (IκBα), which further inhibited the phosphorylation of downstream nuclear factor–κB (NF-κB) in the NF-κB signaling pathway. In vivo, compared with PBMSCs or PRP alone, intra-articular (IA) injection of PBMSCs+PRP enhanced cartilage regeneration and attenuated synovial inflammation in OA-induced rabbits. Conclusion: These results demonstrate that PRP could enhance biological activities, including viability, migration, and adhesion, in PBMSCs. PBMSCs+PRP could rescue ECM degeneration by inhibiting inflammatory signaling in IL-1β–treated OA chondrocytes. In addition, IA injection of PBMSCs+PRP effectively attenuated OA progression in a surgery-induced OA rabbit model. Clinical Relevance: PBMSCs+PRP may provide a promising treatment for knee OA, and this study can advance the related basic research. [ABSTRACT FROM AUTHOR]

Objective: The tibial tubercle‐trochlear groove (TT‐TG) distance is now routinely utilized to help determine whether a realignment procedure is necessary for patients with patellar instability. The tibial tubercle‐posterior cruciate ligament (TT‐PCL) distance has been explored as an alternative measurement. The aim of this study is to compare the reliability of TT‐TG and TT‐PCL; to explore whether there is a relationship between the TT‐PCL and the TT‐TG distance; to determine whether there is a relationship between the TT‐TG and TT‐PCL distances and knee rotation; and to compare the abilities of the TT‐PCL distance and the TT‐TG distance with predicted patellar instability. Method: This systematic review was performed in accordance with PRISMA guidelines. Three databases, PubMed, EMBASE, and Cochrane Central Register of Controlled Trials, were searched from inception to September 2021 to identify clinical studies comparing TT‐TG and TT‐PCL distances to patellar instability. Data on patient baseline characteristics, TT‐TG and TT‐PCL distances, inter‐observer reliability, and area under the receiver‐operating characteristic curve (AUC) were recorded. The methodological quality of the studies was assessed using the quality assessment form recommended by the Agency for Healthcare Research and Quality (AHRQ). Result: Twenty studies were included in the final analysis, comprising 2330 knees from 2260 patients. The current study showed that TT‐TG and TT‐PCL have similar observer reliability. The inter‐ and intra‐observer reliability of TT‐TG ranged from 0.807 to 0.98 and 0.553 to 0.99, respectively. The inter‐ and intra‐observer reliability of TT‐PCL ranged from 0.553 to 0.99 and 0.88 to 0.981, respectively. Six studies compared the AUC for predicting patellar instability and showed that TT‐TG had better predictive performance than TT‐PCL. Three studies reported a correlation between TT‐TG and knee rotation, but no such relationship was found for TT‐PCL. Eight studies reported a weak or moderate correlation between TT‐TG and TT‐PCL. Conclusion: TT‐TG and TT‐PCL have similar inter‐ and intra‐rater reliability (as measured by ICC), but TT‐TG has greater discriminatory power to predict patellar instability than TT‐PCL (as measured by AUC values and odds ratio). However, considering trochlear dysplasia and individual variations, future studies need to find more accurate and individualized methods to predict patellar instability. [ABSTRACT FROM AUTHOR]

Due to their reliability, affordability and high safety, rechargeable aqueous zinc ion batteries (ZIBs) have garnered a lot of attention. Nevertheless, undesirable long-term cycle performance and the inadequate energy density of cathode materials impede the development of ZIBs. Herein, we report a layered CaV4O9-MXene (Ti3C2Tx) composite assembled using CaV4O9 nanosheets on Ti3C2Tx and investigate its electrochemical performance as a new cathode for ZIBs, where CaV4O9 nanosheets attached on the surface of MXene and interlamination create a layered 2D structure, efficiently improving the electrical conductivity of CaV4O9 and avoiding the stacking of MXene nanosheets. The structure also enables fast ion and electron transport. Further discussion is conducted on the effects of adding MXene in various amounts on the morphology and electrochemical properties. The composite shows an improved reversible capacity of 274.3 mA h g−1 at 0.1 A g−1, superior rate capabilities at 7 A g−1, and a high specific capacity of 107.6 mA h g−1 can be delivered after 2000 cycles at a current density of 1 A g−1. The improvement of the electrochemical performance is due to its unique layered structure, high electrical conductivity, and pseudo capacitance behavior. [ABSTRACT FROM AUTHOR]

Channel and spatial attention mechanisms have proven to provide an evident performance boost of deep convolution neural networks. Most existing methods focus on one or run them parallel (series), neglecting the collaboration between the two attentions. In order to better establish the feature interaction between the two types of attentions, a plug‐and‐play attention module is proposed, which is termed as 'CAT'—activating the Collaboration between spatial and channel Attentions based on learned Traits. Specifically, traits are represented as trainable coefficients (i.e. colla‐factors) to adaptively combine contributions of different attention modules to fit different image hierarchies and tasks better. Moreover, the global entropy pooling is proposed apart from global average pooling and global maximum pooling (GMP) operators, which is an effective component in suppressing noise signals by measuring the information disorder of feature maps. A three‐way pooling operation is introduced into attention modules and the adaptive mechanism is applied to fuse their outcomes. Extensive experiments on MS COCO, Pascal‐VOC, Cifar‐100, and ImageNet show that our CAT outperforms the existing state‐of‐the‐art attention mechanisms in object detection, instance segmentation, and image classification. The model and code will be released soon. [ABSTRACT FROM AUTHOR]

The copper alloy is widely used to prepare pipes in ocean engineering. The surface is washed and corroded by seawater for a long time, which gradually shortens the service life of the condenser tube. In order to improve the wear and corrosion resistance of copper alloy, a Ni60-WC coating was fabricated on a preheated copper alloy by laser cladding. Experiments on the Ni60-WC coatings were carried out by SEM, XRD, Vickers-microhardness meter, wear tester and electrochemical workstation. The microstructure, phases, hardness, wear and corrosion resistance were investigated. The results show that from the top to bottom, the microstructures were columnar dendrites, dendritic crystals and grains, respectively. The wear rate of the Ni60-WC coating was only 4.9 × 10−5 mm3·N−1·m−1, which was only 1.14% of copper substrate. In addition, the corrosion current density was 2.34 × 10−7 mA·mm−2, which was much lower than that of copper alloy substrate (1.14 × 10−6 mA·mm−2). The experimental results show that this Ni60-WC coating has a good metallurgical bonding and hardness, and it also has good wear and corrosion resistance, which is helpful to improve the service life of the condenser tube. [ABSTRACT FROM AUTHOR]

Osteoarthritis (OA) is a prevalent and disabling disease that affects a significant proportion of the global population. Urine-derived stem cells (USCs) have shown great prospects in the treatment of OA, but there is no study that has compared them with traditional stem cells.This study aimed to compare the therapeutic efficacy and mechanisms of USCs and adipose-derived stem cells (ADSCs) for OA treatment.Controlled laboratory study.We compared the biological properties of USCs and ADSCs using CCK-8, colony formation, EdU, adhesion, and apoptosis assays. We evaluated the protective effects of USCs and ADSCs on IL-1β–treated OA chondrocytes by chemical staining, immunofluorescence, and Western blotting. We assessed the effects of USCs and ADSCs on chondrocyte autophagy by transmission electron microscopy, immunofluorescence, and Western blotting. We also compared the therapeutic efficacy of intra-articular injections of USCs and ADSCs by gross, histological, micro–computed tomography, and immunohistochemical analyses in an OA rat model induced by anterior cruciate ligament transection.USCs showed higher proliferation, colony formation, DNA synthesis, adhesion, and anti-apoptotic abilities than ADSCs. Both USCs and ADSCs increased the expression of cartilage-specific proteins and decreased the expression of matrix degradation–related proteins and inflammatory factors in OA chondrocytes. USCs had a greater advantage in suppressing MMP-13 and inflammatory factors than ADSCs. Both USCs and ADSCs enhanced autophagy in OA chondrocytes, with USCs being more effective than ADSCs. The autophagy inhibitor 3-MA reduced the enhanced autophagy and protective effects of USCs and ADSCs on OA chondrocytes.To our knowledge, this is the first study to explore the efficacy of USCs in the treatment of knee OA and to compare them with ADSCs. Considering the superior properties of USCs in terms of noninvasive acquisition, a high cost-benefit ratio, and low ethical concerns, our study suggests that they may be a more promising therapeutic option than ADSCs for OA treatment under rigorous regulatory pathways.USCs may be a superior cell source for stem cells to treat knee OA, and this study strengthens the evidence for the application of USCs. [ABSTRACT FROM AUTHOR]

The coating on copper plate is difficult to be fabricated by laser. In order to obtain the optimal parameters of laser cladding coating, the temperature fields at different laser power and scanning speed were investigated and analyzed. The optimal parameters were selected with the depth and width of molten pool and compared with the experimental results. Then, the cooling rate, temperature gradient and solidification rate were calculated and analyzed with the coating's microstructure. The results show that the optimal process parameters are 1500 W and 2 mm/s. And at these parameters, the temperature field is consistent with the morphology of cladding coating. From bottom to top of the coating, the corresponding cooling rates are 1056.7, 936.5 and 762.6 ℃/s, and the microstructure are elongated disordered dendrites, columnar dendrites and planar crystals, respectively. [ABSTRACT FROM AUTHOR]

Benefiting from high safety, low cost, and competitive energy density, aqueous zinc ion batteries (AZIBs) have emerged as very promising technology for grid energy storage. However, the lifetime of AZIBs is severely affected by uncontrolled zinc dendritic growth and undesirable side reaction. To address the problem, natural aluminum silicate hydroxide covered glass fibers separator (AlSi‐GF) is prepared herein using a simple spraying method. Aluminum silicate hydroxide is a complex oxide, where a large number of adsorption sites can adsorb Zn2+ and guide its deposition process. In particular, the Maxwell–Wagner polarization of aluminum silicate hydroxide under an applied electric field contributes to homogenizing the electric field distribution around the interface, thereby modulating zinc deposition and reducing the nucleation overpotential. Impressively, AlSi‐GF separator enables high‐performance zinc‐metal batteries. The symmetric battery with AlSi‐GF separator has a stable voltage polarization and an ultra‐long cycle life of 2280 h at a current density of 1 mA cm−2, and the Zn//V2O5 full cell based on AlSi‐GF separator can exhibit a high specific capacity of 123 mAh g−1 after 1500 cycles at 1 A g−1. This study provides new insights into the design of reliable and cost‐effective separators for metal anodes in energy storage devices. [ABSTRACT FROM AUTHOR]