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Aiming at the new coronavirus that appeared in 2019, which has caused a large number of infected patients worldwide due to its high contagiousness, in order to detect the source of infection in time and cut off the chain of transmission, we developed a new Chest X-ray (CXR) image classification algorithm with high accuracy, simple operation and fast processing for COVID-19. The algorithm is based on ConvNeXt pure convolutional neural network, we adjusted the network structure and loss function, added some new Data Augmentation methods and introduced attention mechanism. Compared with other classical convolutional neural network classification algorithms such as AlexNet, ResNet-34, ResNet-50, ResNet-101, ConvNeXt-tiny, ConvNeXt-small and ConvNeXt-base, the improved algorithm has better performance on COVID dataset.

Cervical cancer is a serious threat to women’s health. In recent years, the incidence rate has increased year by year, and the incidence of cervical cancer tends to be younger. Because of its characteristics of easy recurrence and easy metastasis, the drug therapy of cervical cancer has attracted increasing attention. Coixen ester has anti-cancer and immunomodulatory effects. After years of clinical research, it has been shown to be effective against a variety of cancers and has a growth inhibitory effect on tumor cells. This article aims to study the mechanism of Coixen ester-induced apoptosis of human cervical cancer HeLa cells. This article puts forward what are the causes of cervical cancer, and analyzes the positive effects of traditional Chinese medicine in the prevention and treatment of cervical cancer. During the experiment, the MTT method was used to study the effect of the complex on the proliferation of HeLa cells. The experimental results in this article show that a certain concentration of Coixen ester solution can inhibit cell proliferation and can also reduce cell viability to about 0.35.

Doxorubicin (DOX) is the most effective and extensively used treatment for many tumors. However, its clinical use is hampered by its cardiotoxicity. DOX-induced mitochondrial dysfunction, which causes reactive oxygen species (ROS) generation, cardiomyocyte death, bioenergetic failure, and decreased cardiac function, is a very important mechanism of cardiotoxicity. These cellular processes are all linked by mitochondrial sirtuins (SIRT3-SIRT4). Mitochondrial sirtuins preserve mitochondrial function by increasing mitochondrial metabolism, inhibiting ROS generation by activating the antioxidant enzyme manganese-dependent superoxide dismutase (MnSOD), decreasing apoptosis by activating the forkhead homeobox type O (FOXO) and P53 pathways, and increasing autophagy through AMP-activated protein kinase (AMPK)/mTOR signaling. Thus, sirtuins function at the control point of many mechanisms involved in DOX-induced cardiotoxicity. In this review, we focus on the role of mitochondrial sirtuins in mitochondrial biology and DOX-induced cardiotoxicity. A further aim is to highlight other mitochondrial processes, such as autophagy (mitophagy) and mitochondrial quality control (MQC), for which the effect of mitochondrial sirtuins on cardiotoxicity is unknown.

Atrial fibrillation (AF) is the most common cardiac arrhythmia with a high incidence of stroke. Many circular RNAs (circRNAs) have been demonstrated they are elated to various heart diseases and may play important roles in diagnostics or many pathophysiological processes. Nevertheless, there is Few studies on circRNAs functions in persistent AF. To identify AF-related circRNAs and construct the integrative regulatory network of circular RNAs, miRNAs, and mRNAs, we collected human right atrial appendage tissues from 5 patients suffering persistent AF (AF group) and 5 patients with normal sinus rhythm (NSR group) and characterized the global changes in circRNA expression with high-throughput sequencing technology. The differential expression of circRNAs and the interactions between circRNAs and microRNAs were analyzed. The microRNA expression file GSE68475 dataset was downloaded from the Gene Expression Omnibus (GEO) database to explore the differentially expressed microRNAs. The target genes of overlapped miRNAs were predicted by using DIANA-TarBase v8. We constructed the circRNA- miRNA-mRNA network using Cytoscape (version 3.4.0) and the network topology was analyzed by utilizing CentiScaPe app. Results showed that all of 600 differentially expressed circRNAs related to AF were screened, including 340 up-regulated and 260 down-regulated circRNAs. An integrative regulatory network was constructed, which included 30 circRNAs, 9 miRNAs and 130 target mRNAs of these miRNAs. It was concluded that that 30 circRNAs, including 8 upregulated circRNAs and 22 downregulated circRNAs, were predicted to highly possibly function as sponges of 9 miRNAs to regulate gene expression by using bioinformatics analysis. Moreover, the interactions of hsa-miR-339-5p with its related circRNAs and target mRNAs constructed the hub regulatory network in persistent AF by utilizing topology analysis. Our proposed regulatory network of circRNAs-miRNAs-mRNAs may provide new insight into the potential mechanism underlying persistent AF. Additionally, these important molecular may become novel biomarkers providing a new strategy in diagnosis and therapy of AF.

A new control problem of roll-pitch seeker about the disturbance coupling is investigated in this work. Previous control strategies of roll-pitch seeker rarely considered the effects of the dynamic coupling disturbances from the missile angular motion, and because of the polar coordinate structure, the disturbance rejection strategies of yaw-pitch seeker cannot be utilized directly on roll-pitch seeker. Thus this article presents a new control strategy to improve the disturbance rejection ability of roll-pitch seeker. To analyze the disturbance coupling problem, the roll-pitch seeker model is derived with consideration of the missile body angular motion and torque disturbances. The motion equation of roll-pitch seeker shows that part of the dynamic coupling disturbance can be eliminated by certain choices of inertial parameters. The rest of disturbance is reduced by the stabilization loops using a differentiator-based disturbance compensation controller. Particularly, a missile body angular acceleration estimation method is designed for the compensator based on an adaptive differentiator. In addition, comparisons with other control strategies are carried out via numerical simulations, and the results confirm the effectiveness of the proposed method.

Accurate prediction of load is very important in the management of power system. This paper proposed a two-stage optimization method of gray-Markov model with fractional order accumulation for shor...

Thermal infrared (TIR) object tracking is one of the most challenging tasks in computer vision. This paper proposes a robust TIR tracker based on the continuous correlation filters and adaptive feature fusion (RCCF-TIR). Firstly, the Efficient Convolution Operators (ECO) framework is selected to build the new tracker. Secondly, an optimized feature set for TIR tracking is adopted in the framework. Finally, a new strategy of feature fusion based on average peak-to-correlation energy (APCE) is employed. Experiments on the VOT-TIR2016 (Visual Object Tracking-TIR2016) and PTB-TIR (A Thermal Infrared Pedestrian Tracking Benchmark) dataset are carried out and the results indicate that the proposed RCCF-TIR tracker combines good accuracy and robustness, performs better than the state-of-the-art trackers and has the ability to handle various challenges.

In this paper, we studied a diffusive predator-prey model with competitive interference and Crowley-Martin type functional response. The conditions for local stability of coexisting equilibrium are given by analyzing the eigenvalue spectrum. By using delay as bifurcation parameter, conditions for occurrence of Hopf bifurcation are also given. The property of bifurcating period solutions is investigated by calculating the normal form. Some numerical simulations are performed to support our theoretical result. Our conclusions show that diffusion and delay are two factors that should be considered in establishing the predator-prey model, since they can induce spatially bifurcating period solutions.

Cardiomyocyte death is a fundamental progress in cardiomyopathy. However, the mechanism of triggering the death of myocardial cells remains unclear. Ferroptosis, which is the nonapoptotic, iron-dependent, and peroxidation-driven programmed cell death pathway, that is abundant and readily accessible, was not discovered until recently with a pharmacological approach. New researches have demonstrated the close relationship between ferroptosis and the development of many cardiovascular diseases, and several ferroptosis inhibitors, iron chelators, and small antioxidant molecules can relieve myocardial injury by blocking the ferroptosis pathways. Notably, ferroptosis is gradually being considered as an important cell death mechanism in the animal models with multiple cardiomyopathies. In this review, we will discuss the mechanism of ferroptosis and the important role of ferroptosis in cardiomyopathy with a special emphasis on the value of ferroptosis as a potential novel diagnostic and therapeutic target for patients suffering from cardiomyopathy in the future.

Extracting text information in complex images is a hot spot in pattern recognition research with broad application prospects. Natural scene door numbers produce serious distortion due to blurred images, uneven illumination and low light illumination, which makes it difficult to achieve ideal results in character recognition, and recognizing characters of arbitrary length is even more of a challenge. In this paper, we adopt the improved Niblack’s local threshold segmentation method to segment the images, and mark the connected areas of the segmented images to highlight the important features, and finally input the above pre-processed images to the improved AlexNet network for target detection on SVHN (Street View House Number) to realize the detection of characters in real scenes. The experimental results show that the improved Alexet-based target detection method is able to complete the detection task of streetscape door number characters well with 92.89% correct recognition rate.

At present, the one-stage detector based on the lightweight model can achieve real-time speed, but the detection performance is challenging. To enhance the discriminability and robustness of the model extraction features and improve the detector’s detection performance for small objects, we propose two modules in this work. First, we propose a receptive field enhancement method, referred to as adaptive receptive field fusion (ARFF). It enhances the model’s feature representation ability by adaptively learning the fusion weights of different receptive field branches in the receptive field module. Then, we propose an enhanced up-sampling (EU) module to reduce the information loss caused by up-sampling on the feature map. Finally, we assemble ARFF and EU modules on top of YOLO v3 to build a real-time, high-precision and lightweight object detection system referred to as the ARFF-EU network. We achieve a state-of-the-art speed and accuracy trade-off on both the Pascal VOC and MS COCO data sets, reporting 83.6% AP at 37.5 FPS and 42.5% AP at 33.7 FPS, respectively. The experimental results show that our proposed ARFF and EU modules improve the detection performance of the ARFF-EU network and achieve the development of advanced, very deep detectors while maintaining real-time speed.

Long QT syndrome (LQTS) is an arrhythmic heart disease caused by congenital genetic mutations, and results in increased occurrence rates of polymorphic ventricular tachyarrhythmias and sudden cardiac death (SCD). Clinical evidence from numerous previous studies suggested that beta blockers (BBs), including atenolol, propranolol, metoprolol, and nadolol, exhibit different efficacies for reducing the risk of cardiac events (CEs), such as syncope, arrest cardiac arrest (ACA), and SCD, in patients with LQTS. In this study, we identified relevant studies in MEDLINE, PubMed, embase, and Cochrane databases and performed a meta-analysis to assess the relationship between the rate of CEs and LQTS individuals with confounding variables, including different gender, age, and QTc intervals. Moreover, a network meta-analysis was not only established to evaluate the effectiveness of different BBs, but also to provide the ranked efficacies of BBs treatment for preventing the recurrence of CEs in LQT1 and LQT2 patients. In conclusion, nadolol was recommended as a relatively effective strategy for LQT2 in order to improve the prognosis of patients during a long follow-up period.

Purpose: Nanomicelles (NMs) have been widely used for various biomedical applications due to its unique physiochemical properties. The present study aims to investigate the effects of vascular cell adhesion molecule-1 (VCAM-1)-targeted and peroxisome proliferator-activated receptor δ (PPARδ) agonist (GW0742)-loaded NMs on apoptosis and migration in oxidized low-density lipoprotein (ox-LDL)-induced human aortic vascular smooth muscle cells (HAVSMCs). Methods: The GW0742-loaded NMs (M-GW) and VCAM-1-targeted NMs loaded with GW0742 (TM-GW) were prepared, and then the morphologies and the size distribution of M-GM and TM-GM were observed by transmission electron microscopy (TEM) and dynamic light scattering (DLS), respectively. In vitro drug release assay of M-GM and TM-GM were performed as well. Next, HAVSMCs were cultured in medium containing ox-LDL to mimic atherosclerotic environment, and the effects of free GW0742, M-GM and TM-GM on endocytosis, cell migration and apoptosis, as well as the expression of VCAM-1, and proteins associated with migration and apoptosis were measured in HAVSMCs treated with ox-LDL. Results: M-GM and TM-GM were successfully prepared. VCAM-1 was overexpressed in HAVSMCs treated with ox-LDL, and TM-GM had a strong targeting ability to HAVSMCs treated with ox-LDL compared with M-GM. In addition, compared with free GW0742, both M-GM and TM-GM significantly diminished cell apoptosis and migration in HAVSMCs treated with ox-LDL. Conclusions: TM-GM had a superior suppressing effect on apoptosis and migration of ox-LDL-induced HAVSMCs.

Gravity and magnetic surveys are widely used in geology exploration because of its advantages, such as efficient and economy, green and environment-friendly, widely coverage and strong horizontal resolution. In order to well study in the geology exploration, it is required to comprehensively combine the different scales (different scales data) and different dimensions (satellite data, aeronautical data, ground data, ocean data, well data, etc.) of gravity and magnetic data that were observed in different periods, however, the comprehensive application of the multi-dimensional and multi-scale gravity and magnetic data still stays in the initial stage. In this paper, we do research on the key point of the fusion of potential field data (gravity and magnetic data): the way to fuse the different scales and different dimensions of potential field data into a benchmark and the same surface. Based on this research, we propose a scheme to fuse the multi-dimensional and multi-scale gravity and magnetic data. The synthetic models show that this fusion scheme is able to fuse the multi-dimensional and multi-scale gravity and magnetic data with great fusion results and small errors, in addition, the most important is that the fusion data conform to the characteristics of the potential field data and can meet the needs of data processing in the following steps. One of case studies in China has been accomplished to fuse aeronautical and ground gravity data that are different scales by using this fusion scheme. The fusion scheme we proposed in this study can be used in the fusion of the multi-dimensional (aeronautical, ground and ocean) and multi-scale gravity and magnetic data, which is good for interpretation and popularization.

Three-dimensional (3D) digital images are helpful in studying the physical properties of a medium. Moreover, reconstructing a 3D image from a two-dimensional (2D) image via computer-mathematical modeling is an important process. Based on the relationship between cascaded grids, an ingenious cascaded polymorphic method is proposed in this work to reconstruct a 3D image from a 2D image. By using the cascaded polymorphic method, a patch can be copied directly into a reconstruction grid by matching the patterns between cascaded grids; the polymorphism of the templates correspond to the grid size. To improve the reconstruction performance further, the non-edge region expansion strategy for a layer and the non-edge region replication strategy for adjacent layers were also proposed. A core sample and building material were selected as the test materials, and several effective measurements were used as quantitative means. To display the reconstruction effect intuitively, 2D reconstruction experiments were also performed along with the 3D experiment. The results show that the reconstruction speed is significantly improved using the cascaded polymorphic method, and the morphological features of the 3D reconstruction are clearly promoted.

Weaning failure from mechanical ventilation is an important clinical problem, the traditional methods of assessing whether patients can be weaned from mechanical ventilation or not cannot meet the clinical needs. Finding more effective weaning indicators to determine the optimal timing of weaning has important clinical value for improving the outcome of weaning and reducing the mortality of patients. As a new method of assessing respiratory function of patients, electrical impedance tomography (EIT) is gradually applied to the clinic, and its guided assessment of respiratory function may open a new way for directing successful weaning. This article reviews the progress of EIT in ventilation weaning, in order to provide a new judgment method and theoretical basis for the successful weaning.

There are two main contributions in this paper: Firstly, by analyzing the frequency domain features and Mel domain features, we can identify footstep events and non-footstep events. Secondly, we compared the two footstep sound signals of the same person in frequency domain under different experimental conditions, finding that almost all of their peak frequencies and trough frequencies in the main frequency band are respectively corresponding one-to-one. However for the two different people, even under the same experimental conditions, it is difficult to have the same peak frequencies and trough frequencies in the main frequency band of their footstep sound signals. Therefore, this feature of footstep sound signals can be used to identify different people.

The issue of toxicity and chemical stability are two concerns for organic–inorganic hybrid perovskites, impeding their further commercial applications. Double perovskite (CH3NH3)2SnI6 with a bandgap of 1.81 eV and stable chemical valence of Sn (+4) is considered as a promising alternative. By first-principles calculations, the electronic properties, defect physics, and interface engineering of the perovskite are investigated in this work. It is found that (i) MA2SnI6 has a direct bandgap with a large dispersion of a lower conduction band. Due to the direct I 5p–5p transition between band edges, the light absorption can be as high as 105 cm−1 in the visible range. (ii) An Sn rich and I poor condition is suggested when MA2SnI6 is used as an electron transporting material (ETM) because of its high n-type electronic conductivity. An Sn poor and I rich condition is proposed when MA2SnI6 is prepared for photovoltaic application, because it can suppress the formation of non-radiation centers. (iii) ICBA and Spiro are proposed to be suitable ETM and hole transporting material, respectively, in MA2SnI6 based solar cells.

Through first-principles calculations, the photovoltaic properties of Cs2PdI6 were investigated and found that (i) Cs2PdI6 has a quasi-direct band gap nature, and strong p–d coupling of lower conduction bands is responsible for light electrons; (ii) dominant Pdi and Ii defects would be produced at a deep level in the band gap which acts as charge trapping states. Thus, should be passivated by suitable external doping, if Cs2PdI6 works as a solar cell absorber; (iii) The Cs2Pd(I1-x Br x )6 alloy is highly miscible. Tunable band gap depending on composition x has a non-linear bowing behavior occurring a lowest band gap at composition Cs2Pd(I0.7Br0.3)6.

Lead halide perovskite has shown amazing optoelectronic performance, while the issues of its toxicity and the thermal instability remain to be intractable. Recently, lead-free halide perovskite Cs2PdBr6 as a narrow bandgap semiconductor with long-term stability has attracted great attention. Herein, through performing first-principles calculations, we find that (i) Cs2PdBr6 has a quasi-direct bandgap with an indirect bandgap of 1.71 eV and a 20 meV smaller direct bandgap. The bandgap increases when the lattice constant enlarges, which is opposite to that of the traditional zincblende semiconductors. (ii) Band offsets between Cs2PdBr6 and popular perovskites indicate that Cs2PdBr6 is more difficult to be doped p-type according to the doping limit rule. The commonly used electron transport materials such as TiO2, SnO2, ZnO, and C60 can also be suitable for Cs2PdBr6 solar cell devices, but the commonly used hole transport materials with a lower highest occupied molecular orbital is an alternative. (iii) Cs2PdBr6 is shown to be difficult to be intrinsic p-type. The electric conductivity would not be too high due to the charge compensation of the defects if there is no suitable external doping. Since the Pd poor and Br rich condition can suppress the formation of the defects with deep levels, this condition is proposed to synthesize Cs2PdBr6 as a solar cell absorber.

In order to obtain an overview of the gamma-ray bursts (GRBs), we need a full sample. In this paper, we collected 6289 GRBs (from GRB 910421 to GRB 160509A) from the literature, including prompt emission, afterglow and host galaxy properties. We hope to use this large sample to reveal the intrinsic properties of GRB. We have listed all the data in machine readable tables, including the properties of the GRBs, correlation coefficients and linear regression results of two arbitrary parameters, and linear regression results of any three parameters. These machine readable tables could be used as a data reservoir for further studies on the classifications or correlations. One may find some intrinsic properties from these statistical results. With this comprehensive table, it is possible to find relations between different parameters, and to classify the GRBs into different kinds of sub-groups. With the completion, it may reveal the nature of GRBs and may be used as tools like pseudo-redshift indicators, standard candles, etc. All the machine readable data and statistical results are available on the website of the journal., Comment: Comments welcome. The machine readable data and figure sets will be available in ApJS. The original collected data are available: https://drive.google.com/drive/folders/0B9pJKjl_EXbvcFNMYnQ0WVFLTjQ