Search

Background: Photodynamic therapy (PDT) has shown good short-term efficacy in the treatment of oral leukoplakia (OLK). However, the malignant transformation of OLK was seldom evaluated in most PDT studies. Therefore, this study evaluated the effect of PDT on the risk of malignant transformation of OLK. Methods: Kaplan-Meier survival analysis, COX regression, and sensitivity analysis were used to evaluate the effects of PDT on the risk of malignant transformation of OLK. Subgroup analyses were performed to explore the role of PDT in OLK patients with different clinical characteristics. Results: OLK patients with older age (HR=1.032, P = 0.018) and non-homogeneous lesion (HR=2.104, P = 0.044) had higher risk of malignant transformation. Patients who had finished a complete course of PDT (HR=0.305, P = 0.006) had a significant lower risk of malignant transformation, while those who hadn't finished a complete course of PDT (HR=0.692, P = 0.352) cannot be considered to have such a protective effect. In the subgroup analyses, complete PDT course showed a significant protective effect on malignant transformation of OLK in patients with female sex, no smoking or drinking habits, non-homogeneous lesions, lesions on oral mucosa outside the dangerous region, and any grade of epithelial dysplasia. Conclusions: A complete course of PDT could significantly reduce the risk of malignant transformation of OLK, especially in those patients with risk factors of malignant transformation.

Background: The treatment of oral leukoplakia (OLK) with aminolaevulinic acid photodynamic therapy (ALA-PDT) is widespread. Nonetheless, there is variation in efficacy. Therefore, this study constructed a model for predicting the short-term efficacy and recurrence of OLK after ALA-PDT. Methods: The short-term efficacy and recurrence of ALA-PDT were calculated by statistical analysis, and the relevant influencing factors were analyzed by Logistic regression and COX regression model. Finally, prediction models for total response (TR) rate, complete response (CR) rate and recurrence in OLK patients after ALA-PDT treatment were established. Features from pathology sections were extracted using deep learning autoencoder and combined with clinical variables to improve prediction performance of the model. Results: The logistic regression analysis showed that the non-homogeneous (OR: 4.911, P: 0.023) OLK and lesions with moderate to severe epithelial dysplasia (OR: 4.288, P: 0.042) had better short-term efficacy. The area under receiver operating characteristic curve (AUC) of CR, TR and recurrence predict models after the ALA-PDT treatment of OLK patients is 0.872, 0.718, and 0.564, respectively. Feature extraction revealed an association between inflammatory cell infiltration in the lamina propria and recurrence after PDT. Combining clinical variables and deep learning improved the performance of recurrence model by more than 30 %. Conclusions: ALA-PDT has excellent short-term efficacy in the management of OLK but the recurrence rate was high. Prediction model based on clinicopathological characteristics has excellent predictive effect for short-term efficacy but limited effect for recurrence. The use of deep learning and pathology images greatly improves predictive value of the models.

Deep learning has achieved tremendous success in the field of object detection. The efficient detection of infrared small targets using deep learning methods remains a challenging task. Infrared small targets are often detected in high-resolution features. Extracting high-level semantic features layer by layer in the network may lead to the loss of deep-layer targets. However, performing global detection on high-resolution feature maps results in high computational costs. To address this issue, we propose the aware distribute and sparse network (ADSNet) to preserve deep-layer small target features while accelerating inference speed. Specifically, we design the aware fusion distribute module (AFD) to aggregate global features and enhance the representation capability of deep-layer features. Subsequently, the aware cascaded sparse module (ACS) is utilized to guide step-by-step high-resolution feature sparsification. Experimental results demonstrate that the proposed method achieves accurate segmentation in various detection scenarios and for diverse target morphologies, effectively suppressing false alarms while controlling computational expenses. Ablation experiments further validate the effectiveness of each component.

Optical wireless video transmission technology combines the advantages of high data rates, enhanced security, large bandwidth capacity, and strong anti-interference capabilities inherent in optical communication, establishing it as a pivotal technology in contemporary data transmission networks. However, video data comprises a large volume of image information, resulting in substantial data flow with significant redundant bits. To address this, we propose an adaptive block sampling compressive sensing algorithm that overcomes the limitations of sampling inflexibility in traditional compressive sensing, which often leads to either redundant or insufficient local sampling. This method significantly reduces the presence of redundant bits in video images. First, the sampling mechanism of the block-based compressive sensing algorithm was optimized. Subsequently, a wireless optical video transmission experimental system was developed using a Field-Programmable Gate Array chip. Finally, experiments were conducted to evaluate the transmission of video optical signals. The results demonstrate that the proposed algorithm improves the peak signal-to-noise ratio by over 3 dB compared to other algorithms, with an enhancement exceeding 1.5 dB even in field tests, thereby significantly optimizing video transmission quality. This research contributes essential technical insights for the enhancement of wireless optical video transmission performance.

Abstract Background Periodontitis is a common chronic oral disease which seriously affects people's quality of life. Although human herpes simplex virus (HSV) is also found in periodontal lesions, the association between HSV infection and periodontitis is unclear. Methods The National Health and Nutrition Examination Survey (NHANES) data for 2009–2010, 2011–2012 and 2013–2014 was combined, and the association between HSV infection and periodontitis in the general population and particular subgroups was investigated through weighted multi-logistic analyses. Results There were 4,733 participants aged 30–50 years old with clinically assessed periodontitis concurrent with HSV infection. In general analysis, after adjusted for covariates, both HSV-1 (OR = 1.09, P

Space laser communication, with its strong anti-jamming capability, high transmission rate and good adaptability, offers hope for the establishment of 5G mobile networks in areas that are not conducive to the erection of cables, such as islands and remote land areas. Turbulent scintillation effect is one of the important factors affecting the performance of laser communication, which can lead to the increase of communication BER and even communication interruption. Based on the working principle of the photoelectric detector in atmospheric turbulence, an optical communication receiving system based on the detector gain factor regulation control is designed, which calculates the scintillation variance according to the received signal in real time, establishes the function conversion relationship between the scintillation variance and the gain factor, realizes the closed-loop regulation control of the detector gain factor, and improves the SNR of the receiving system. A ground-based 13km static laser communication experiment was set up to test the reception performance, and the test results show that the system reduces the communication BER by more than two orders of magnitude and can be kept at 1E-6 under medium to weak turbulence (discriminated by flash variance) at a communication rate of 2.5Gbps. The technology was applied to the test of laser 5G signal transmission between the airship and the ground, and for the first time, the mobile communication (access network) signal transmission with a downlink speed of 1.230Gbps and an uplink speed of 76.4Mbps is realized, which verified the performance of mobile signal transmission between the mobile base station and the fixed station on the ground.

Space dynamic communication base stations are characterized by high mobility, flexible deployment and wide coverage. It has a wide range of needs in the fields of emergency communication, earthquake relief and island communication. To solve the problem of a limited number of users due to the limited bandwidth of space base stations, so we should improve the reliability and efficiency of data transmission between space mobile base stations. According to the characteristics of the airship platform, a blimp-borne laser communication terminal applied to space dynamic base stations is designed to meet the demand for bi-directional transmission of 5G signal laser carriers in space between airships. The experimental results show that the blimp-borne laser communication terminal achieves an overall technical index of capture probability is better than 98%, the average capture time is 5s, the tracking accuracy is better than 6–15 μrad, the communication rate is 2.5 Gbps and BER is 1E-7. In order to realize the real-time evaluation of the performance of laser communication system under the turbulent channel and guide the research of anti-turbulence fading method, a real-time test method of communication channel turbulence characteristics based on the principle of light intensity scintillation is proposed. And the real-time test of turbulence characteristics of airship inclined link and the horizontal link is completed. The research results play a positive role in promoting the development of 5G mobile technology and space optical communication technology.

The data transmission between 5G floating base stations will be an important application area of the free space optical (FSO) link, but the problem of atmospheric disturbance will directly affect the application effect. An atmospheric turbulence suppression algorithm based on avalanche photodiode adaptive gain control (APDAGC) for the laser transmission terminal was proposed to suppress atmospheric turbulence. The given design mechanism and experimental results demonstrate its function to improve the performance of FSO. When APDAGC is over 1 km FSO, the variance of intensity fluctuation is lowered from 0.046 to 0.009, with the bit error rate reduced from 4.82E-6 to 1E-12. Comparatively, as APDAGC is over 6.5 km FSO, the variance of intensity fluctuation is decreased from 1.767 to 0.376, with the bit error rate varying from 4.6E-2 to 2.4E-4. Moreover, it was used for the first FSO transmission of 5G floating base station signals on an airship platform.

In light of COVID-19 and the extent of global economic interdependence, it is essential to understand risk spillover effects between China's stock market and international commodity market in order to optimize risk control and management and provide early warning. The aim of this research is to examine the spillover mechanisms between the Chinese stock market and the global commodity market using data from eleven specific industries. The results show that the Risk Spillover index of industrial and optional consumer industries in China's stock market is relatively high. This industry is more vulnerable to fluctuations in the international commodity market and is the main risk spillover industry; The energy and financial industries have great risk spillover effects on the international commodity market. The volatility spillovers between the Chinese stock market and the international commodity market are asymmetric: the Chinese stock market is mainly affected by the risk spillovers from gold and silver, while the international commodity market is mainly affected by the risk spillovers from the real estate, energy, and financial sectors. The results of this analysis can be used in future works to develop a risk hedging model to examine how bulk commodities differ in terms of portfolio weight, hedging ratio, and hedging efficiency.

This paper examines the risk spillover mechanism between China's stock market and international commodity markets using selected industry data series on soybean copper, gold, silver, sugar, and crude oil. Based on the results of this analysis, a DCC-GARCH model is used to describe the dynamic correlation, build a risk hedging model, calculate the risk hedging efficiency, and evaluate the risk hedging effect. According to the findings, the industrial and optional consumer industries are the primary risk receiving markets, while the energy and finance industries are the primary risk export markets. The stock market crash in 2015 and the COVID-19 epidemic in 2020 made the risk spillover between China’s stock market and international commodity markets surge. On average, the commodity copper is the most efficient hedge, followed by silver, while commodities such as sugar, gold and soybeans are less effective, and copper will continue to be a good hedge for the Chinese stock market in the coming months.

An algorithm to extract the disk boundary and center of EUV solar image using the Sobel operator, Fuzzy Local Information C-Means Clustering algorithm (FLICM), and the least square circle fitting method is proposed in this paper. The Sobel operator can determine the solar disk boundary preliminarily, and then the image is processed further using the FLICM algorithm. After the background is removed based on the clustered image and the boundary points can be highlighted, these points are fitted using the least square circle fitting method as the final boundary circle. The solar data used in this paper was from the observation of the Solar Dynamics Observatory Atmospheric Imaging Assembly (SDO/AIA) instrument. The 2523 19.3 nm solar images covering solar minimum, moderate solar activity, and more active suns were calculated using the proposed algorithm to analyze the accuracy statistically. The statistical comparison results demonstrate that the method is accurate and effective. This method can support the processing of solar EUV images and serve the operational system of a space weather forecast.

It is important to clarify the reaction behavior of 2CaO·SiO2 (C2S) during hot metal dephosphorization. In this study, C2S was prepared and added to steel slag to investigate the reaction of C2S particles with CaO–SiO2–FeO–P2O5 slag at 1723 K. The diffusion coefficient of phosphorus in C2S was calculated. In addition, the influence of the addition of BaO to C2S was discussed. The results show that the diffusion coefficient of phosphorus in C2S is 9.23 × 10−14 m2·s−1. The Ca in C2S can be replaced by Ba. Small particles in the solid solution were easily generated from the C2S body by the addition of BaO, which is beneficial for improving the phosphorus partition between the C2S solid phase and the liquid phase of the slag.

The initial pointing unit of the line of sight (LOS) operating in the open-loop mode is an important part of the space laser communication system, which directly determines the size of the field of uncertainty (FOU) and the length of the scan time. In this paper, the composition and working principle of the initial pointing of the LOS in the dynamic laser communication system are studied in detail. The initial pointing angle (IPA) of the LOS is derived by applying the principle of coordinate transformation, and the factors affecting the size of the FOU are analyzed. It is proposed to introduce the extended Kalman filtering technique into the initial pointing to reduce the size of the FOU. In the demonstration experiment of the dynamic laser communication (including airship-ship and aircraft-aircraft), the dual-antenna global positioning system/inertial navigation system composite device is applied to obtain position, attitude, and other parameters in real-time to realize the performance test of the initial pointing system. The size of the FOU is measured with a target-viewing camera, and the filtered and unfiltered results were compared.

The background of our research is, designing a precise phase detection sensor for high-speed coherent homodyne systems, and combining it with optical phase-locked loops (OPLLs) to achieve coherent demodulation and carrier recovery. For existing phase sensors, there are problems, such as low phase gain, long dead-time, and difficulty in distinguishing directions. Therefore, we proposed a multilevel-loop compound control phase sensor based on exclusive-OR gates. The sensing system consists of three loops. The tunable range of the temperature loop is 30 GHz. Its tuning rate value is 50 MHz/s. In addition, the inner ring consists of a piezoelectric loop and an acousto-optic frequency shifter loop. According to demand, we established a relevant model, and analyzed and calculated the parameters. The reliability and validity of this sensor are substantiated after setting up the experimental environment. The results show that the lock-in range is 30 GHz, the bandwidth is 1.5 MHz, and the real-time performance of the PLL is improved. In a communication test with a rate of 5 Gbps, the realized bit error ratio is 1.55 × 10-8 when the optical power of the signal is -40.4 dBm. Therefore, this sensor system improves detection sensitivity. At the end of this paper, we propose some ideas to improve sensitivity, which will be the focus of our next phase.

High-dynamic range imaging technology is an effective method to improve the limitations of a camera’s dynamic range. However, most current high-dynamic imaging technologies are based on image fusion of multiple frames with different exposure levels. Such methods are prone to various phenomena, for example motion artifacts, detail loss and edge effects. In this paper, we combine a dual-channel camera that can output two different gain images simultaneously, a semi-supervised network structure based on an attention mechanism to fuse multiple gain images is proposed. The proposed network structure comprises encoding, fusion and decoding modules. First, the U-Net structure is employed in the encoding module to extract important detailed information in the source image to the maximum extent. Simultaneously, the SENet attention mechanism is employed in the encoding module to assign different weights to different feature channels and emphasis important features. Then, a feature map extracted from the encoding module is input to the decoding module for reconstruction after fusing by the fusion module to obtain a fused image. Experimental results indicate that the fused images obtained by the proposed method demonstrate clear details and high contrast. Compared with other methods, the proposed method improves fused image quality relative to several indicators.