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Image semantic segmentation based on deep learning attracted much attention in the field of computer vision in recent years. In the past few decades, the tremendous developments of medical imaging technology have made it possess an increasingly important role in diagnosis. Therefore, the image semantic segmentation method based on the deep learning algorithm is widely considered by many researchers in the medical image processing field. In this paper, first of all, we introduced some semantic segmentation methods based on deep learning, including point cloud data-based methods, Recurrent Neural Network (RNN) based methods, attention mechanism-based methods, transformer-based methods, and Generative Adversarial Network (GAN) based methods. Then, the characteristics of each method and the problems improved by each method in the field of medical imaging are shown respectively, for example, point cloud data can better express the information of biological tissue structure to improve the capacity of processing global contextual dependencies, attention mechanism assists the model quickly discover key information of input images, transformer improve the effect of segmentation tasks, and GAN has superior data generation capacity that they have excellent performance in generating realistic-looking images. And we summarize the performance of each method in the medical dataset by distinct metrics. Finally, some problems of theory, architecture and application in future research were discussed.

Background and aims LncRNA plasmacytoma variant translocation 1 (PVT1) plays a regulatory role in some cardiovascular diseases, but its role in atherosclerosis (AS) remains barely explored. The study aimed to investigate the effects of PVT1 on high fat diet-induced AS and its potential mechanisms. Methods and results ApoE −/− mice were fed with high fat diet for 8 weeks to establish an AS model. Lentiviral vectors containing PVT1 short hairpin RNA (PVT1-shRNA) or NC-shRNA were administered by tail vein injection. Cell viability, apoptosis, inflammatory factor secretion, and cellular oxidative stress were measured to evaluate oxidized low-density lipoprotein (ox-LDL)-induced human umbilical vein endothelial cell (HUVEC) injury. Dual-luciferase reporter gene and RNA immunoprecipitation assays were used to confirm the interaction between miR-153-3p and PVT1 or growth factor receptor binding protein 2 (GRB2). Atherosclerotic lesions, lipid deposition, and cell apoptosis in aorta were analyzed by H&E, Oil Red O, and TUNEL straining. PVT1 knockdown alleviated ox-LDL-induced inflammation, apoptosis and oxidative stress in HUVECs. PVT1 acted as a sponge of miR-153-3p, and GRB2 was confirmed as a target of miR-153-3p. MiR-153-3p overexpression attenuated the enhanced effects of PVT1 on ox-LDL-induced cell damage. GRB2 overexpression reversed the mitigating effects of miR-153-3p on ox-LDL-caused injury. Inhibiting PVT1 restrained the activation of ERK1/2 and p38 pathway via miR-153-3p/GRB2 axis. Additionally, silencing PVT1 in vivo reduced atherosclerotic plaques, lipid deposition, inflammation, oxidative stress, and apoptosis in AS mice. Conclusion PVT1 knockdown alleviated ox-LDL-induced vascular endothelial cell injury and atherosclerosis through miR-153-3p/GRB2 axis via ERK1/2 and p38 pathway.

The all-inorganic nature of CsPbI3 perovskites allows to enhance stability in perovskite devices. Research efforts have led to improved stability of the black phase in CsPbI3 films; however, these strategies-including strain and doping-are based on organic-ligand-capped perovskites, which prevent perovskites from forming the close-packed quantum dot (QD) solids necessary to achieve high charge and thermal transport. We developed an inorganic ligand exchange that leads to CsPbI3 QD films with superior phase stability and increased thermal transport. The atomic-ligand-exchanged QD films, once mechanically coupled, exhibit improved phase stability, and we link this to distributing strain across the film. Operando measurements of the temperature of the LEDs indicate that KI-exchanged QD films exhibit increased thermal transport compared to controls that rely on organic ligands. The LEDs exhibit a maximum EQE of 23 % with an electroluminescence emission centered at 640 nm (FWHM: ≈31 nm). These red LEDs provide an operating half-lifetime of 10 h (luminance of 200 cd m-2 ) and an operating stability that is 6× higher than that of control devices.

Background Pulmonary vein (PV) data are commonly measured on multiplanar image reformation (MPR) images and volume rendering (VR) images. Purpose To compared and analyze the advantages and disadvantages of PV data based on VR images and MPR images. Material and Methods A total of 94 patients with atrial fibrillation (AF) with imaging data were included in the study. The respective image postprocessing time and the three surgical interventionists’ preferences for the two images were recorded. A paired t-test or chi-square test was used to compare their difference, and P Results There was no statistically significant difference between the data values including the maximal and minimal ostial diameters of the left superior PV (LSPV), the left inferior PV (LIPV), the right superior PV (RSPV), and the right inferior PV (RIPV) obtained by VR and MPR images ( P > 0.05). Yet, the mean postprocessing time of VR images (15.10 ± 3.05 min) was shorter compared to MPR images (16.54 ± 2.60 min) ( t = 22.84, P Conclusion PV data measurement could be performed on both VR and MRP images; however, the data on VR images were more intuitive and more accessible for interventional surgeons.

Herein is developed a ternary heterostructured catalyst, based on a periodic array of 1D TiN nanotubes, with a TiO2 nanoparticulate intermediate layer and a In2O3-x(OH)y nanoparticulate shell for improved performance in the photocatalytic reverse water gas shift reaction. It is demonstrated that the ordering of the three components in the heterostructure sensitively determine its activity in CO2 photocatalysis. Specifically, TiN nanotubes not only provide a photothermal driving force for the photocatalytic reaction, owing to their strong optical absorption properties, but they also serve as a crucial scaffold for minimizing the required quantity of In2O3-x(OH)y nanoparticles, leading to an enhanced CO production rate. Simultaneously, the TiO2 nanoparticle layer supplies photogenerated electrons and holes that are transferred to active sites on In2O3-x(OH)y nanoparticles and participate in the reactions occurring at the catalyst surface.

Colloidal quantum dot (CQD) solar cells composed of ionic halide passivated active layers benefit from improved passivation and high carrier mobility because of short interparticle distance. Howeve...

Colloidal quantum dot (QD) solids are emerging semiconductors that have been actively explored in fundamental studies of charge transport1 and for applications in optoelectronics2. Forming high-quality QD solids—necessary for device fabrication—requires substitution of the long organic ligands used for synthesis with short ligands that provide increased QD coupling and improved charge transport3. However, in perovskite QDs, the polar solvents used to carry out the ligand exchange decompose the highly ionic perovskites4. Here we report perovskite QD resurfacing to achieve a bipolar shell consisting of an inner anion shell, and an outer shell comprised of cations and polar solvent molecules. The outer shell is electrostatically adsorbed to the negatively charged inner shell. This approach produces strongly confined perovskite QD solids that feature improved carrier mobility (≥0.01 cm2 V−1 s−1) and reduced trap density relative to previously reported low-dimensional perovskites. Blue-emitting QD films exhibit photoluminescence quantum yields exceeding 90%. By exploiting the improved mobility, we have been able to fabricate CsPbBr3 QD-based efficient blue and green light-emitting diodes. Blue devices with reduced trap density have an external quantum efficiency of 12.3%; the green devices achieve an external quantum efficiency of 22%. A solution-based ligand-exchange strategy enables the realization of close-packed quantum dot solid films with near-unity photoluminescence quantum yield and high charge carrier mobility.

Deep-blue light-emitting diodes (LEDs) (emitting at wavelengths of less than 450 nm) are important for solid-state lighting, vivid displays and high-density information storage. Colloidal quantum dots, typically based on heavy metals such as cadmium and lead, are promising candidates for deep-blue LEDs, but these have so far had external quantum efficiencies lower than 1.7%. Here we present deep-blue light-emitting materials and devices based on carbon dots. The carbon dots produce emission with a narrow full-width at half-maximum (about 35 nm) with high photoluminescence quantum yield (70% ± 10%) and a colour coordinate (0.15, 0.05) closely approaching the standard colour Rec. 2020 (0.131, 0.046) specification. Structural and optical characterization, together with computational studies, reveal that amine-based passivation accounts for the efficient and high-colour-purity emission. Deep-blue LEDs based on these carbon dots display high performance with a maximum luminance of 5,240 cd m−2 and an external quantum efficiency of 4%, notably exceeding that of previously reported quantum-tuned solution-processed deep-blue LEDs. Deep-blue high-colour-purity light-emitting materials are developed by using amine-based edge passivation. The light-emitting diodes based on the carbon dots exhibit a maximum luminance of 5,240 cd m–2 and an external quantum efficiency of 4%.

Solar cells capable of light-harvesting during daytime and light-emitting at night are multifunctional semiconductor devices with many potential applications. Here we report that halide perovskite heterojunction interfaces can be refined to yield stable and efficient solar cells. The cell can also operate effectively as an ultralow-voltage light-emitting diode with a peak external quantum efficiency of 3.3%. Spectroscopic and microscopic studies reveal that double-heterojunction refinement with wide-bandgap salts is key to densifying the packing of perovskite grains and enlarging the bandgaps of the perovskite surfaces that are in contact with charge transport semiconductors. The refined perovskite enables a simple device with dual actions of solar cells and light-emitting diodes. This type of all-in-one device has the potential for multifunctional harvesting-storage-utilization systems. This article is protected by copyright. All rights reserved.

Background With the rapid development of China's national economy, people pay more and more attention to disaster prevention and reduction and the impact of landslide disasters. Before the construction of various projects, disaster investigation, assessment and prediction shall be carried out to avoid in advance as much as possible, or necessary preventive measures shall be taken to prevent and reduce the occurrence of disasters as much as possible. The internal causes and treatment of landslide are studied from the aspects of point-to-point, line surface comprehensive prediction and disaster prevention and control. At the same time, the landslide damaged by high-speed and long-distance is also deeply studied. In particular, the prediction of landslide occurrence time has made a breakthrough, forming a theoretical system from treatment to prevention. However, the landslide geological disaster directly endangers the production and life of the people in the disaster area and causes psychological trauma. Accurate monitoring of micro deformation before landslide is of great significance to landslide early warning system. When using ground laser scanning (TLS) technology for landslide monitoring, the traditional point cloud data processing results, that is, comparing the changes of landslides between different surfaces, have a great deviation from the actual monitoring values. Research Objects and Methods This paper proposes a method to compare landslide changes by extracting the surface feature points of the monitoring object, and designs two verification experiments, namely Experiment 1 carton tilt change experiment under different design angles and Experiment 2 landslide physical model experiment. Then, in two experiments, this method is used to extract feature points with the same name. Finally, the change of inclination and the settlement of landslide are calculated. In order to test the impact of emotional behavior, this study selected subjects stimulated after the disaster, and selected 60 subjects, including 30 men and 30 women. We used the anxiety scale designed by Kim as the measurement scale, and evaluated the scale by Likert scoring method. Pearson correlation, standard deviation and statistical significance were used to illustrate the correlation. Independent sample t-test was used to verify the difference between high anxiety group and low anxiety group. According to the statistical value of anxiety, participants were divided into three groups: low, medium and high anxiety groups. The questionnaire includes two kinds of anxiety, namely debilitating anxiety and promoting anxiety. The relationship between anxiety and self-efficacy of subjects with different majors and genders was investigated by t-test, univariate, multivariate analysis of variance and regression analysis. Results Using the method proposed in this paper, the change of carton inclination in Experiment 1 and the settlement of landslide surface in different periods in Experiment 2 are obtained, and the error of the results is analyzed to verify the feasibility of the method proposed in this paper. Test participants can effectively alleviate psychological stress and prevent depression. The data showed that the DASS-21 comprehensive score of subjects participating in the test was 1.7 times that of subjects not participating in the test. In contrast, without participation, they are more likely to show depression, anxiety and stress, and tend to be passive in simple coping styles. The improved method can effectively alleviate the psychological pressure of employees and improve the ability to actively deal with pressure. Through the correlation analysis of emotion regulation ability, the data results show that structural equation model is used to investigate the mediating role of core self-evaluation and emotion regulation self-efficacy between stressful life events and life satisfaction. The maximum likelihood estimation method is used to estimate the intermediary effect. The results show that the fitting indexes of this model are χ 2=314.015, df=218, χ 2/df=1.44, CFI=0.958, TLI=0.94, RMSEA=0.043. All paths in the model are significant. According to the effect decomposition principle of path analysis, the total effect from stressful life events to life satisfaction is equal to direct effect plus indirect effect. The total indirect effect in this study is equal to the sum of three specific mediating effects, which is -0.299. The proportion of indirect effect in the total effect is -0.299 / (-0.469) + (-0.299) = 0.389, that is, 38.9% of the effect of stressful life events on life satisfaction is through core self-evaluation and emotion regulation self-efficacy. Conclusion Using the method proposed in this paper, the visual expression of the internal cause of landslide is realized. This method can calculate the displacement and inclination of key parts in different periods, and obtain the stable state of the monitoring object through comparative analysis. It is consistent with the traditional analysis method, but it improves the efficiency and accuracy, provides reliable data support for the subsequent landslide prediction, and avoids people's property loss and psychological trauma to the greatest extent. Acknowledgement This work was financially supported by the Research Foundation of Education Bureau of Jiangxi Province, China (No. GJJ190944) and the National Natural Science Foundation of China Regional Science Fund Project (42162023).

Background: Residual viable tumor cells after ablation at the tumor periphery serve as the source for tumor recurrence, leading to treatment failure. Purpose: To develop a novel three-dimensional (3D) multi-modal perfusion-thermal electrode system completely eradicating medium-to-large malignancies. Materials and Methods: This study included five steps: (i) design of the new system; (ii) production of the new system; (iii) ex vivo evaluation of its perfusion-thermal functions; (iv) mathematic modeling and computer simulation to confirm the optimal temperature profiles during the thermal ablation process, and; (v) in vivo technical validation using five living rabbits with orthotopic liver tumors. Results: In ex vivo experiments, gross pathology and optical imaging demonstrated the successful spherical distribution/deposition of motexafin gadolinium administered through the new electrode, with a temperature gradient from the electrode core at 80 °C to its periphery at 42 °C. An excellent repeatable correlation of temperature profiles at varying spots, from the center to periphery of the liver tumor, was found between the mathematic simulation and actual animal tumor models (Pearson coefficient ≥0.977). For in vivo validation, indocyanine green (ICG) was directly delivered into the peritumoral zones during simultaneous generation of central tumoral lethal radiofrequency (RF) heat (>60 °C) and peritumoral sublethal RF hyperthermia (

PurposeTo validate the feasibility of using peri-tumoral radiofrequency hyperthermia (RFH)-enhanced chemotherapy to obliterate hepatic tumor margins.Method and MaterialsThis study included in vitro experiments with VX2 tumor cells and in vivo validation experiments using rabbit models of liver VX2 tumors. Both in vitro and in vivo experiments received different treatments in four groups (n=6/group): (i) RFH-enhanced chemotherapy consisting of peri-tumoral injection of doxorubicin plus RFH at 42°C; (ii) RFH alone; (iii) doxorubicin alone; and (iv) saline. Therapeutic effect on cells was evaluated using different laboratory examinations. For in vivo experiments, orthotopic hepatic VX2 tumors in 24 rabbits were treated by using a multipolar radiofrequency ablation electrode, enabling simultaneous delivery of both doxorubicin and RFH within the tumor margins. Ultrasound imaging was used to follow tumor growth overtime, correlated with subsequent histopathological analysis.ResultsIn in vitro experiments, MTS assay demonstrated the lowest cell proliferation, and apoptosis analysis showed the highest apoptotic index with RFH-enhanced chemotherapy, compared with the other three groups (pin vivo experiments, ultrasound imaging detected the smallest relative tumor volume with RFH-enhanced chemotherapy (pConclusionThis study demonstrates that peri-tumoral RFH can specifically enhance the destruction of tumor margins in combination with peri-tumoral injection of a chemotherapeutic agent. This new interventional oncology technique may address the critical clinical problem of frequent marginal tumor recurrence/persistence following thermal ablation of large (>3 cm) hepatic cancers.

Energy level alignment between host and dopant molecules plays a critical role in exciton formation and harvesting in light emission zone of organic light-emitting diodes. Understanding the mechanism for predicting energy level alignment is thus important in materials selection for fabricating high-performance organic light-emitting devices. Here we show that host-dopant energy level alignment strongly depends on film thickness and substrate work function by using X-ray and ultraviolet photoemission spectroscopy. Invariant Gaussian density of states fails to explain the experimental data. We speculate that energy disorder in molecules next to the surface dictates the alignment. Ultraviolet photoemission spectroscopy measurements of several archetypical organic semiconductors confirm our speculation. An empirical interface disorder function is derived and used to construct a functional Gaussian density of states to compute host energy levels. Host-dopant energy level alignment is then computed by applying the universal energy alignment rule and is found in excellent agreement with the experimental data. Organic light emitting diodes are an important component of current technologies, and methods to enhance their efficiencies are under constant investigation. The authors demonstrate that disorder near the surface of these systems is responsible for the energy alignment between their host and dopant molecules and hence their overall efficiency.

Colloidal quantum dots (CQDs) are promising materials for infrared (IR) light detection due to their tunable bandgap and their solution processing; however, to date, the time response of CQD IR photodiodes is inferior to that provided by Si and InGaAs. It is reasoned that the high permittivity of II-VI CQDs leads to slow charge extraction due to screening and capacitance, whereas III-Vs-if their surface chemistry can be mastered-offer a low permittivity and thus increase potential for high-speed operation. In initial studies, it is found that the covalent character in indium arsenide (InAs) leads to imbalanced charge transport, the result of unpassivated surfaces, and uncontrolled heavy doping. Surface management using amphoteric ligand coordination is reported, and it is found that the approach addresses simultaneously the In and As surface dangling bonds. The new InAs CQD solids combine high mobility (0.04 cm

Perovskite light‐emitting diodes (PeLEDs) have attracted tremendous research interest in recent years. Cesium lead bromide's (CsPbBr3) high color purity, intrinsically high photoluminescence quantum yield, and tunable emission wavelength make it a strong candidate as an emitter for light‐emitting applications. Organic charge transport materials and their impact on the growth mode of the perovskite layer have a pivotal influence on the device performance. Herein, it is reported that hole transport layers (HTLs) with higher glass transition temperatures (Tg) are critical to facilitate the growth of crystalline perovskites and thus the color purity. Second phase regions with higher Pb density are observed in films growing on HTLs with inadequate lower Tg. A minimum 100 °C glass transition is found to be essential to grow cesium lead bromides with sharp emission peaks. In addition to high glass transition temperature, high ionization energy (>5.6 eV) is also found to be important to remove the HTL/perovskite injection barrier. The optimal device in this study is fabricated with 3,5‐di(9H‐carbazol‐9‐yl)tetraphenylsilane (SimCP2) as the HTL and the device shows a very sharp 19 nm full‐width at half‐maximum emission.

Herein is developed a ternary heterostructured catalyst, based on a periodic array of 1D TiN nanotubes, with a TiO

Colloidal quantum dots (CQDs) are promising materials for IR light detection due to their tunable bandgap and solution processing; but to date, the time response of CQD IR photodiodes has been inferior to that provided by Si and InGaAs. We reasoned that the high permittivity of II-VI CQDs leads to slow charge extraction due to screening and capacitance; whereas III-Vs – if their surface chemistry could be mastered – offer a strong covalent character for low permittivity and fast operation. In initial studies, we found that existing covalent character led to imbalanced charge transport in InAs, the result of unpassivated surfaces and uncontrolled heavy doping. We report surface management using amphoteric ligand coordination and find that it addresses simultaneously the In and As surface dangling bonds. The new InAs CQD solids combine high mobility (0.04 cm2 V-1 s-1) with a 4x reduction in permittivity compared to PbS CQDs. The resulting photodiodes achieve a response time faster than 300 ps – a more than 100x improvement compared to the best previously-reported CQD photodiodes – combined with an external quantum efficiency (EQE) of 30% at 940 nm.

Light-emitting diodes (LEDs) based on perovskite quantum dots have shown external quantum efficiencies (EQEs) of over 23% and narrowband emission, but suffer from limited operating stability

Metal halide perovskites show promise for light-emitting diodes (LEDs) owing to their facile manufacture and excellent optoelectronic performance, including high color purity and spectral stability, especially in the green region. However, for blue perovskite LEDs, the emission spectrum line width is broadened to over 25 nm by the coexistence of multiple reduced-dimensional perovskite domains, and the spectral stability is poor, with an undesirable shift (over 7 nm) toward longer wavelengths under operating conditions, degradation that occurs due to phase separation when mixed halides are employed. Here we demonstrate chloride insertion-immobilization, a strategy that enables blue perovskite LEDs, the first to exhibit narrowband (line width of 18 nm) and spectrally stable (no wavelength shift) performance. We prepare bromide-based perovskites and then employ organic chlorides for dynamic treatment, inserting and

Efficient lead-free perovskite light-emitting diodes with color coordinates that fulfill Rec. 2100 requirements are demonstrated., It remains a central challenge to the information display community to develop red light-emitting diodes (LEDs) that meet demanding color coordinate requirements for wide color gamut displays. Here, we report high-efficiency, lead-free (PEA)2SnI4 perovskite LEDs (PeLEDs) with color coordinates (0.708, 0.292) that fulfill the Rec. 2100 specification for red emitters. Using valeric acid (VA)—which we show to be strongly coordinated to Sn2+—we slow the crystallization rate of the perovskite, improving the film morphology. The incorporation of VA also protects tin from undesired oxidation during the film-forming process. The improved films and the reduced Sn4+ content enable PeLEDs with an external quantum efficiency of 5% and an operating half-life exceeding 15 hours at an initial brightness of 20 cd/m2. This work illustrates the potential of Cd- and Pb-free PeLEDs for display technology.

Objective: To establish the technique of intratumoral combination therapy of radiofrequency hyperthermia (RFH) with herpes simplex virus-thymidine kinase/ganciclovir (HSV-TK/GCV) gene therapy for rat ovarian cancers.Material and methods: This study consisted of three parts: (1) in vitro experiments to establish the 'proof of principal' that combination of RFH and HSV-TK gene therapy has the synergistic effect on human ovarian cancer cells; (2) creation of bioluminescence imaging-detectable rat ovarian cancer model; and (3) in vivo experiments using this rat model to validate the technical feasibility of the combination therapy. Cells and nude rats were divided into four groups: (i) combination therapy (HSV-TK/GCV + RFH); (ii) RFH; (iii) HSV-TK/GCV; and (iv) phosphate-buffered saline (PBS). Data were analyzed using Dunnett t-test or Kruskal-Wallis test.Results: Cell proliferation assay demonstrated significantly greater reduction in viable cells with the combination therapy [0.52 (0.43, 0.61)] compared to other treatments [RFH 0.90 (0.84, 0.96), HSV-TK/GCV 0.71 (0.53, 0.88), PBS 1 (1, 1); p < .05]. For 24 rat models with bioluminescence imaging-detectable orthotopic ovarian cancer (n = 6 per group), optical imaging demonstrated significantly decreased relative bioluminescence signal with the combination therapy [0.81 (0.52, 1.08)] compared to other treatments [RFH 3.60 (2.34, 4.86), HSV-TK/GCV 2.21 (1.71, 2.71), PBS 3.74 (3.19, 4.29); p < .001]. Ultrasound imaging demonstrated the smallest relative tumor volume with the combination therapy [0.78 (0.45, 1.11) versus 3.50 (2.67, 4.33), 2.10 (0.83, 3.37), 3.70 (1.79, 5.61); p < .05].Conclusion: The feasibility of intratumoral RFH-enhanced HSV-TK/GCV gene therapy was established on a unique rat model with molecular imaging-detectable orthotopic ovarian cancer.