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Abstract Introduction Parameters, such as left ventricular ejection fraction, peak strain dispersion, global longitudinal strain, etc. are influential and clinically interpretable for detection of cardiac disease, while manual detection requires laborious steps and expertise. In this study, we evaluated a video-based deep learning method that merely depends on echocardiographic videos from four apical chamber views of hypertensive cardiomyopathy detection. Methods One hundred eighty-five hypertensive cardiomyopathy (HTCM) patients and 112 healthy normal controls (N) were enrolled in this diagnostic study. We collected 297 de-identified subjects’ echo videos for training and testing of an end-to-end video-based pipeline of snippet proposal, snippet feature extraction by a three-dimensional (3-D) convolutional neural network (CNN), a weakly-supervised temporally correlated feature ensemble, and a final classification module. The snippet proposal step requires a preliminarily trained end-systole and end-diastole timing detection model to produce snippets that begin at end-diastole, and involve contraction and dilatation for a complete cardiac cycle. A domain adversarial neural network was introduced to systematically address the appearance variability of echo videos in terms of noise, blur, transducer depth, contrast, etc. to improve the generalization of deep learning algorithms. In contrast to previous image-based cardiac disease detection architectures, video-based approaches integrate spatial and temporal information better with a more powerful 3D convolutional operator. Results Our proposed model achieved accuracy (ACC) of 92%, area under receiver operating characteristic (ROC) curve (AUC) of 0.90, sensitivity(SEN) of 97%, and specificity (SPE) of 84% with respect to subjects for hypertensive cardiomyopathy detection in the test data set, and outperformed the corresponding 3D CNN (vanilla I3D: ACC (0.90), AUC (0.89), SEN (0.94), and SPE (0.84)). On the whole, the video-based methods remarkably appeared superior to the image-based methods, while few evaluation metrics of image-based methods exhibited to be more compelling (sensitivity of 93% and negative predictive value of 100% for the image-based methods (ES/ED and random)). Conclusion The results supported the possibility of using end-to-end video-based deep learning method for the automated diagnosis of hypertensive cardiomyopathy in the field of echocardiography to augment and assist clinicians. Trial registration Current Controlled Trials ChiCTR1900025325, Aug, 24, 2019. Retrospectively registered.

BackgroundNormal hepatic functional reserve is the key to avoiding liver failure after liver surgery. This study investigated the assessment of hepatic functional reserve using liver shear wave velocity (LSWV) combined with biochemical indicators, tumor volume, and portal vein diameter.MethodsIn this single-center prospective study, a total of 123 patients with hepatocellular carcinoma (HCC) were divided into a test group (n=92) and a validation group (n=31). All patients were Child-Pugh grade A. The indocyanine green retention rate at 15 min (ICG-R15), liver shear wave velocity (LSWV), portal vein diameter (Dpv), alanine aminotransferase (ALT), aspartate transaminase (AST), alkaline phosphatase (ALP), γ-glutamyl transpeptidase (γ-GGT), albumin (ALB), prothrombin time (PT), and also liver tumor volume (maximum diameter ≤5 cm) were measured. In the test group, multiple parameters were used to evaluate hepatic functional reserve, and the multiparametric model was established. Receiver operating characteristic (ROC) curve analysis was conducted to assess the diagnostic performance of the multiparametric model. In the validation group, the predictive effectiveness of the multiparametric model was analyzed using consistency tests.ResultsIt was revealed that LSWV, ALB, and PT were statistically significant in evaluation of the hepatic functional reserve (P

Abstract Evidence of the triglyceride‐glucose (TyG) index as an independent predictor of arterial stiffness in stage 1 hypertension patients is scarce. This study aimed to explore the association between TyG index and arterial stiffness in this population. A total of 1041 individuals from 32 centers with normal/elevated blood pressure (BP,

Abstracts: To enhance the tribological and wear properties of carbon steel at high temperatures, FeAl-TiB2-Cux coatings were produced using an extreme high-speed laser cladding process. The coatings had varying Cu content and were made from original powders including Fe, Al, Cu, and TiB2. The study focused on the phase composition, microstructure, and wear mechanism of the coating. Results showed that the composite coatings mainly consisted of FeAl, TiB2, and Cu9Al4 with uniformly distributed remelted TiB2 particles. When Cu content was less than 3wt%, plastic deformation and oxidation wear dominated the coating's wear mode; when it exceeded 3wt%, abrasive wear became more prominent alongside oxidation wear. It was found that the tribo-film was formed by metal oxides during the dry sliding process. Especially, the coating with 5wt% Cu content exhibited the lowest friction coefficient wear rate at 600℃ due to the self-lubricating properties of CuO.

Abstract Background Studies on deep learning (DL)-based models in breast ultrasound (US) remain at the early stage due to a lack of large datasets for training and independent test sets for verification. We aimed to develop a DL model for differentiating benign from malignant breast lesions on US using a large multicenter dataset and explore the model’s ability to assist the radiologists. Methods A total of 14,043 US images from 5012 women were prospectively collected from 32 hospitals. To develop the DL model, the patients from 30 hospitals were randomly divided into a training cohort (n = 4149) and an internal test cohort (n = 466). The remaining 2 hospitals (n = 397) were used as the external test cohorts (ETC). We compared the model with the prospective Breast Imaging Reporting and Data System assessment and five radiologists. We also explored the model’s ability to assist the radiologists using two different methods. Results The model demonstrated excellent diagnostic performance with the ETC, with a high area under the receiver operating characteristic curve (AUC, 0.913), sensitivity (88.84%), specificity (83.77%), and accuracy (86.40%). In the comparison set, the AUC was similar to that of the expert (p = 0.5629) and one experienced radiologist (p = 0.2112) and significantly higher than that of three inexperienced radiologists (p

Background Osteosarcoma is a common primary bone tumour in children and adolescents. Circular RNAs (circRNAs) exert vital functions in human diseases, including osteosarcoma. Therefore, we explored the role of circ_0016347 in osteosarcoma. Methods The real-time quantitative polymerase chain reaction (RT-qPCR) was used to detect the expression levels of circ_0016347, microRNA-661 (miR-661), and Interleukin-6 receptor (IL6R) in osteosarcoma tissues and cells. The proliferation of osteosarcoma cells was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazol-3-ium bromide (MTT) and EdU experiments. The migration and invasion were determined by transwell assay. The cell cycle distribution and apoptosis were assessed by flow cytometry assay. The association relationships among circ_0016347, miR-661, and IL6R were analyzed by dual-luciferase reporter assays. The western blot assay was employed to assay the protein expression. A xenograft experiment was established to clarify the functional role of circ_0016347 inhibition in vivo. Results Circ_0016347 was obviously overexpressed in osteosarcoma tissues and cells compared with control groups. The suppression of circ_0016347 impeded proliferation, migration, invasion, and cell cycle and induced apoptosis in osteosarcoma cells, which was overturned by knockdown of miR-661. Consistently, circ_0016347 knockdown repressed tumour growth in vivo. Moreover, miR-661 directly targeted and inhibited IL6R, and the upregulation of IL6R reversed miR-661-induced effects on osteosarcoma cells. Furthermore, circ_0016347 could regulate IL6R expression through miR-661. Inhibition of circ_0016347 also inactivated the Janus kinase 2 (JAK2)/Transcription 3 (STAT3) signalling pathway in osteosarcoma cells by IL6R. Conclusion Circ_0016347 functioned as an oncogene in osteosarcoma at least in part by the miR-661/IL6R axis and JAK2/STAT3 signalling pathway.

The J-TEXT capability is enhanced compared to two years ago with several upgrades of its diagnostics and the increase of electron cyclotron resonance heating (ECRH) power to 1 MW. With the application of electron cyclotron wave (ECW), the ECW assisted plasma startup is achieved; the tearing mode is suppressed; the toroidal injection of 300 kW ECW drives around 24 kA current; fast electrons are generated with toroidal injected ECW and the runaway current conversion efficiency increases with ECRH power. The mode coupling between 2/1 and 3/1 modes are extensively studied. The coupled 2/1 and 3/1 modes usually lead to major disruption. Their coupling can be either suppressed or avoided by external resonant magnetic perturbation fields and hence avoids the major disruption. It is also found that the 2/1 threshold of external field is significantly reduced by a pre-excited 3/1 mode, which can be either a locked island or an external kink mode. The disruption control is studied by developing prediction methods capable of cross tokamak application and by new mitigation methods, such as the biased electrode or electromagnetic pellet injector. The high-density operation and related disruptions are studied from various aspects. Approaching the density limit, the collapse of the edge shear layer is observed and such collapse can be prevented by applying edge biasing, leading to an increased density limit. The density limit is also observed to increase, if the plasma is operated in the poloidal divertor configuration or the plasma purity is increased by increasing the pre-filled gas pressure or ECRH power during the start-up phase.

BackgroundLiver cirrhosis is closely associated with cardiac dysfunction. The aims of this study were to evaluate left ventricular systolic function in patients with hepatitis B cirrhosis by non-invasive left ventricular pressure-strain loop (LVPSL) technique, and to explore the correlation between myocardial work indices and liver function classification.MethodsAccording to the Child-Pugh classification, 90 patients with hepatitis B cirrhosis were further divided into three groups: Child-Pugh A group (n = 32), Child-Pugh B group (n = 31), and Child-Pugh C group (n = 27). During the same period, 30 healthy volunteers were recruited as the control (CON) group. Myocardial work parameters, which included global work index (GWI), global constructive work (GCW), global wasted work (GWW), and global work efficiency (GWE), were derived from the LVPSL and compared among the four groups. The correlation between myocardial work parameters and Child-Pugh liver function classification was evaluated, and the independent risk factors affecting left ventricular myocardial work in patients with cirrhosis were investigated by univariable and multivariable linear regression analysis.ResultsGWI, GCW and GWE of Child-Pugh B and C groups were lower than those of CON group, while GWW was higher than that of CON group, and the changes were more obvious in Child-Pugh C group (P

In the operation of urban rail transits, train delays occur frequently, and emergency management is one of the key factors to ensure the service quality. For speed limit scenarios with high demand, this paper takes the train running in the restricted manual (RM) mode in the speed limit zone as an example and discusses a coping method by jointing train rescheduling and passenger flow control. With the goal of maximizing the number of passengers served and minimizing total train delay, a nonlinear optimization model is constructed by taking the train operation-related requirements and passenger flow control-related indicators as constraints, and the model is reformulated to a mixed-integer programming (MIP) model with quadratic constraints, which can be solved by the Gurobi solver. In order to obtain effective solutions faster, a two-stage approach is discussed, which first obtains a rescheduling timetable and then dynamically adjusts the requirement of boarding equalization to obtain the passenger flow control scheme. The validity of the model and the solution approach are discussed with the help of numerical experiments. The results suggest that the model and solution approach are feasible. When the number of trains is fixed, the reasonable implementation of passenger flow control will help to increase the number of passengers served, and the pursuit of a higher equalization of boarding is not conducive to the number of passengers served and the full utilization of transport capacity. The two-stage approach has certain advantages over the direct computing method. The methods in this paper have a guiding value for emergency decision-making in similar delay scenarios.

The cross-line operation mode, based on interoperability technology, is becoming increasingly common in urban rail transits (URTs). Compared to trains running on a single line, cross-line trains can greatly facilitate transfer passengers. Taking the scenario of emergent large transfer passenger flow as an example, this paper explores the train rescheduling problem for serving transfer passengers by adding a cross-line backup train. To maximize the number of transfer passengers served by the cross-line backup train, a nonlinear optimization model is constructed by taking into account the operation parameters of planned trains on relevant lines, the deviation degree of the planned timetable, the utilization of the cross-line backup train, and the passenger flow calculation as constraints, and some linearization lemmas are proposed to transform it into a mixed integer programming (MIP) model with quadratic terms. A case study is conducted to discuss the impact of parameter changes on the objective function value and the applicability of different solution approaches. The results suggest that the operation trajectory of the cross-line backup train has an effect on the objective function value, which is related to the demand, the deviation tolerance of the planned timetable, and the running efficiency tolerance of the cross-line backup train. The corresponding methods help guide the organization of the cross-line backup train for large transfer passenger flow scenarios.

The adequate interfacial pressure of silicone rubber in cable intermediate joints is a basic condition to ensure the normal operation of cable joints, while high temperature and ageing in the operation of actual cables and accessories would affect the magnitude of interfacial pressure. The uniaxial tensile force of two different silicone rubbers for 10 kV cold-shrink joints at different temperatures and thermal ageing times was measured by experiment, and the Yeoh rubber intrinsic structure model was fitted according to the measured data. The material model was embedded into a two-dimensional axisymmetric finite element simulation model of the structure, and the relationship between the interference, temperature, thermal ageing time and interfacial pressure was investigated. The results show that the interfacial pressure increases linearly with the increase in interference. At the same interference, the interfacial pressure at the root of insulating silicone rubber and semiconducting silicone rubber increased by 9.1%, 12.3%, 6.4% and 9.2%, 16.3%, 5.6%, respectively, at 50, 75, and 100 °C compared with room temperature, and the largest interfacial pressure of cable joints was at 75 °C. Using the established ageing life prediction model based on the Arrhenius principle, the service life of the accessories was predicted to be 28.9 years at 90 °C of operating temperature and interfacial pressure greater than 55% of initial interfacial pressure.

Continuum robots have good adaptability in unstructured and complex environments. However, affected by their inherent nature of flexibility and slender structure, there are challenges in high-precision motion and load. Thus, stiffness adjustment for continuum robots has consistently attracted the attention of researchers. In this paper, a stiffness adjustment mechanism (SAM) is proposed and built in a growth-controllable continuum robot (GCCR) to improve the motion accuracy in variable scale motion. The self-stiffness adjustment is realized by antagonism through cable force transmission during the length change of the continuum robot. With a simple structure, the mechanism has a scarce impact on the weight and mass distribution of the robot and required no independent actuators for stiffness adjustment. Following this, a static model considering gravity and end load is established. The presented theoretical static model is applicable to predict the shape deformations of robots under different loads. The experimental validations showed that the maximum error ratio is within 5.65%. The stiffness of the robot can be enhanced by nearly 79.6%.

Abstract Background Microvascular insufficiency plays an important role in the development of diabetic cardiomyopathy (DCM), therapeutic angiogenesis has been mainly used for the treatment of ischemic diseases. This study sought to verify the preclinical performance of SonoVue microbubbles (MB) combined ultrasound (US) treatment on myocardial angiogenesis in the rat model of DCM and investigate the optimal ultrasonic parameters. Methods The male Sprague–Dawley (SD) rats were induced DCM by streptozotocin through intraperitoneal injecting and fed with high-fat diet. After the DCM model was established, the rats were divided into the normal group, DCM model group, and US + MB group, while the US + MB group was divided into four subsets according to different pulse lengths (PL) (8 cycles;18 cycle;26 cycle; 36 cycle). After all interventions, all rats underwent conventional echocardiography to examine the cardiac function. The rats were sacrificed and myocardial tissue was examined by histology and morphometry evaluations to detect the myocardial protective effect of SonoVue MBs using US techniques. Results From morphologic observation and echocardiography, the DCM rats had a series of structural abnormalities of cardiac myocardium compared to the normal rats. The US-MB groups exerted cardioprotective effect in DCM rats, improved reparative neovascularization and increased cardiac perfusion, while the 26 cycle group showed significant therapeutic effects on the cardiac functions in DCM rats. Conclusion This strategy using SonoVue MB and US can improve the efficacy of angiogenesis, even reverse the progress of cardiac dysfunction and pathological abnormalities, especially using the 26 cycle parameters. Under further study, this combined strategy might provide a novel approach for early intervention of DCM in diabetic patients.

Objectives The aim of this study was to evaluate the performance of deep learning-based detection and classification of carotid plaque (DL-DCCP) in carotid plaque contrast-enhanced ultrasound (CEUS).Methods and analysis A prospective multicentre study was conducted to assess vulnerability in patients with carotid plaque. Data from 547 potentially eligible patients were prospectively enrolled from 10 hospitals, and 205 patients with CEUS video were finally enrolled for analysis. The area under the receiver operating characteristic curve (AUC) was used to evaluate the effectiveness of DL-DCCP and two experienced radiologists who manually examined the CEUS video (RA-CEUS) in diagnosing and classifying carotid plaque vulnerability. To evaluate the influence of dynamic video input on the performance of the algorithm, a state-of-the-art deep convolutional neural network (CNN) model for static images (Xception) was compared with DL-DCCP for both training and holdout validation cohorts.Results The AUCs of DL-DCCP were significantly better than those of the experienced radiologists for both the training and holdout validation cohorts (training, DL-DCCP vs RA-CEUS, AUC: 0.85 vs 0.69, p

Marine collagen peptides have high potential in promoting skin wound healing. This study aimed to investigate wound healing activity of collagen peptides derived from Sipunculus nudus (SNCP). The effects of SNCP on promoting healing were studied through a whole cortex wound model in mice. Results showed that SNCP consisted of peptides with a molecular weight less than 5 kDa accounted for 81.95%, rich in Gly and Arg. SNCP possessed outstanding capacity to induce human umbilical vein endothelial cells (HUVEC), human immortalized keratinocytes (HaCaT) and human skin fibroblasts (HSF) cells proliferation and migration in vitro. In vivo, SNCP could markedly improve the healing rate and shorten the scab removal time, possessing a scar-free healing effect. Compared with the negative control group, the expression level of tumor necrosis factor-α, interleukin-1β and transforming growth factor-β1 (TGF-β1) in the SNCP group was significantly down-regulated at 7 days post-wounding (p < 0.01). Moreover, the mRNA level of mothers against decapentaplegic homolog 7 (Smad7) in SNCP group was up-regulated (p < 0.01); in contrast, type II TGF-β receptors, collagen I and α-smooth muscle actin were significantly down-regulated at 28 days (p < 0.01). These results indicate that SNCP possessed excellent activity of accelerating wound healing and inhibiting scar formation, and its mechanism was closely related to reducing inflammation, improving collagen deposition and recombination and blockade of the TGF-β/Smads signal pathway. Therefore, SNCP may have promising clinical applications in skin wound repair and scar inhibition.

This study presents a new Perona–Malik (PM) model which is based on new non‐local means (NLM) theory for an image denoising. In the proposed model, the intensity, space position and gradient information are introduced into NLM model, which weakens the staircasing effect and preserves edge in a processed image. The new PM model enhances the denoising capability, and decreases fine characteristics to be over‐smoothed. Comparative experiments show that the denoising capability of the proposed model is superior to the other three existing models.

In this paper, a novel NiAl-based composite reinforced with different content Ti _3 AlC _2 particles was fabricated by thermal explosion using Ni, Al, and Ti _3 AlC _2 powders as starting materials. The microstructure and high-temperature wear behavior of NiAl-Ti _3 AlC _2 composites at 600 °C were investigated. The result showed that increasing Ti _3 AlC _2 content (lower than 15 wt%) could improve the fracture toughness of NiAl-Ti _3 AlC _2 , but for the composites with 20 wt%Ti _3 AlC _2 content, the fracture toughness decreased due to low relative density. Wear mechanism of composites was related to the Ti _3 AlC _2 content, the composite with a lower content exhibits oxidation wear, and higher content composite demonstrated both oxidation wear and abrasive wear.

In order to improve the self-lubricating properties of NiAl-WC composite, a novel solid-lubricating material, NiAl/WC-Fe _x (x = 5, 10, 15 and 20 in weight percent) composites were synthesized by thermal explosion using Ni-Al-WC-Fe mixed powders. The microstructure, phase constituent, and tribological behavior of NiAl/WC-Fe _x composites at 800 °C were studied. According to the results, the addition of Fe could reduce the cracks of the composites. Compared with NiAl/WC, the increased Fe content could reduce the friction coefficient and high-temperature wear rate due to its enhanced ductility, oxidation, and low shearing strength. In particular, composite with 10 wt% Fe content had the lowest friction coefficient and wear rate because of the self-lubricating behavior of Fe at elevated temperature. The result also showed that the wear mechanism of NiAl/WC-Fe _x is related to Fe content at high-temperature.

We present a new external-beam radiation therapy system using very-high-energy (VHE) electron/photon beams generated by a centimeter-scale laser plasma accelerator built in a robotic system. Most types of external-beam radiation therapy are delivered using a machine called a medical linear accelerator driven by radio frequency (RF) power amplifiers, producing electron beams with an energy range of 6–20 MeV, in conjunction with modern radiation therapy technologies for effective shaping of three-dimensional dose distributions and spatially accurate dose delivery with imaging verification. However, the limited penetration depth and low quality of the transverse penumbra at such electron beams delivered from the present RF linear accelerators prevent the implementation of advanced modalities in current cancer treatments. These drawbacks can be overcome if the electron energy is increased to above 50 MeV. To overcome the disadvantages of the present RF-based medical accelerators, harnessing recent advancement of laser-driven plasma accelerators capable of producing 1-GeV electron beams in a 1-cm gas cell, we propose a new embodiment of the external-beam radiation therapy robotic system delivering very high-energy electron/photon beams with an energy of 50–250 MeV; it is more compact, less expensive, and has a simpler operation and higher performance in comparison with the current radiation therapy system.

Objective: To evaluate whether or not highly active antiretroviral therapy is associated with carotid artery stiffness in human immunodeficiency virus-positive patients in Henan Province, China. Method: Fifty human immunodeficiency virus-positive patients with at least a 5-year history of highly active antiretroviral therapy use and 50 human immunodeficiency virus-positive patients without a history of highly active antiretroviral therapy use were enrolled in this study. Carotid artery intima-media thickness and stiffness were determined by quantitative inter-media thickness and quantitative artery stiffness, respectively. Results: No statistically significant difference in carotid artery intima-media thickness and stiffness was observed between groups. A significant association between human immunodeficiency virus infection time and carotid artery stiffness was observed, but no significant association between human immunodeficiency virus infection time and intima-media thickness was found. No significant association between intima-media thickness, stiffness, and CD4+ and CD8+ T-cell counts were observed. Conclusion: The first-line highly active antiretroviral therapy currently used in China is not associated with carotid artery stiffness in human immunodeficiency virus-positive patients with good highly active antiretroviral therapy compliance. Human immunodeficiency virus may play a role in the development of atherosclerosis. Keywords: Artery stiffness, AIDS, Ultrasound, HAART

The translationally controlled tumor protein (TCTP) is an abundant, ubiquitous, and conserved protein which plays important roles in a number of biological processes. In the present study, the TCTP in shrimp Litopenaeus vannamei was analyzed. The TCTP of L.vannamei, a 168-amino-acid polypeptide, shares a high degree of similarity with TCTPs from other species, having two TCTP protein signatures at the 45-55 aa and 123-145 aa motif. The mRNA and protein levels from different tissues were detected with the highest in muscle and the lowest in heart among all examined tissues. In addition, temporal TCTP expression was significantly up-regulated at 16 h and 48 h following infection with white spot syndrome virus (WSSV). Lastly, silencing of TCTP with dsRNA led to a significant increase of WSSV loads. These results provide new insights into the importance of TCTP as an evolutionarily conserved molecule for shrimp innate immunity against virus infection.