Image Processing for Denoising Using Composite Adaptive Filtering Methods Based on RMSE

As one of the carriers for human communication and interaction, images are prone to contamination by noise during transmission and reception, which is often uncontrollable and unknown. Therefore, how to denoise images contaminated by unknown noise has gradually become one of the research focuses. In order to achieve blind denoising and separation to restore images, this paper proposes a method for image processing based on Root Mean Square Error (RMSE) by integrating multiple filtering methods for denoising. This method includes Wavelet Filtering, Gaussian Filtering, Median Filtering, Mean Filtering, Bilateral Filtering, Adaptive Bandpass Filtering, Non-local Means Filtering and Regularization Denoising suitable for different types of noise. We can apply this method to denoise images contaminated by blind noise sources and evaluate the denoising effects using RMSE. The smaller the RMSE, the better the denoising effect. The optimal denoising result is selected through comprehensively comparing the RMSE values of all methods. Experimental results demonstrate that the proposed method effectively denoises and restores images contaminated by blind noise sources.

Correlation between cerebral neurotransmitters levels by proton magnetic resonance spectroscopy and HbA1c in patients with type 2 diabetes

BACKGROUND Cognitive dysfunction is the main manifestation of central neuropathy.Although cognitive impairments tend to be overlooked in patients with diabetes mellitus(DM),there is a growing body of evidence linking DM to cognitive dysfunction.Hyperglycemia is closely related to neurological abnormalities,while often disregarded in clinical practice.Changes in cerebral neurotransmitter levels are associated with a variety of neurological abnormalities and may be closely related to blood glucose control in patients with type 2 DM(T2DM).AIM To evaluate the concentrations of cerebral neurotransmitters in T2DM patients exhibiting different hemoglobin A1c(HbA1c)levels.METHODS A total of 130 T2DM patients were enrolled at the Department of Endocrinology of Shanghai East Hospital.The participants were divided into four groups according to their HbA1c levels using the interquartile method,namely Q1(<7.875%),Q2(7.875%-9.050%),Q3(9.050%-11.200%)and Q4(≥11.200%).Clinical data were collected and measured,including age,height,weight,neck/waist/hip circumferences,blood pressure,comorbidities,duration of DM,and biochemical indicators.Meanwhile,neurotransmitters in the left hippocampus and left brainstem area were detected by proton magnetic resonance spectroscopy.RESULTS The HbA1c level was significantly associated with urinary microalbumin(mALB),triglyceride,low-density lipoprotein cholesterol(LDL-C),homeostasis model assessment of insulin resistance(HOMA-IR),and beta cell function(HOMA-β),N-acetylaspartate/creatine(NAA/Cr),and NAA/choline(NAA/Cho).Spearman correlation analysis showed that mALB,LDL-C,HOMA-IR and NAA/Cr in the left brainstem area were positively correlated with the level of HbA1c(P<0.05),whereas HOMA-βwas negatively correlated with the HbA1c level(P<0.05).Ordered multiple logistic regression analysis showed that NAA/Cho[Odds ratio(OR):1.608,95%confidence interval(95%CI):1.004-2.578,P<0.05],LDL-C(OR:1.627,95%CI:1.119-2.370,P<0.05),and HOMA-IR(OR:1.107,95%CI:1.031-1.188,P<0.01)were independent predictors of poor glycemic control.CONCLUSION The cerebral neurotransmitter concentrations in the left brainstem area in patients with T2DM are closely related to glycemic control,which may be the basis for the changes in cognitive function in diabetic patients.

多策略模式下RRT算法的优化

快速扩展随机树算法(RRT)在导航领域得到了广泛的使用,但是仍然存在采样点随机性强、方向性弱、算法规划效率低等问题。在面对复杂环境时,算法不稳定且路径重复性低。针对这种情况,提出了一种多策略模式下改进的RRT算法(以下简称为M-RRT),能够在复杂环境中提高路径寻优的稳定性和效率。首先对地图进行预处理保证最优性,接着模拟植物生长和光线反射定律提供引导点,然后依据评价函数设定动态步长,最后结合剪枝优化与曲线拟合的方法优化路径。实验证明M-RRT算法比Dijkstra算法路径长度减少了6%,比RRT算法时间减少了53%,在3000次迭代和100次的实验下导航全部成功且路径长度标准差小于2%。利用图像预处理、光线反射和植物生长的方法能够弥补RRT算法在复杂、大面积地图导航中存在的不足。

On-treatment monitoring of liver fibrosis with serum hepatitis B core-related antigen in chronic hepatitis B

BACKGROUND Non-invasive evaluation for liver fibrosis is clinically important,especially in patients with undetectable hepatitis B virus(HBV)DNA treated with nucleoside analogs.AIM To clarify the monitoring power of hepatitis B core-related antigen(HBcrAg)for hepatic histologic changes in patients with chronic hepatitis B(CHB)treated with entecavir.METHODS This prospective multicenter study used multiple ordinal and multivariate logistics regression analysis to assess variables associated with Ishak fibrosis score and regression for fibrosis regression,respectively,in 403 CHB patients,including 374 with entecavir for 72 weeks(291 underwent paired liver biopsy)and 29 as controls.RESULTS Level of HBcrAg correlated negatively with liver fibrosis staging(γ=-0.357,P<0.001)in hepatitis B e antigen(HBeAg)-positive patients,and positively with liver fibrosis staging in HBeAg-negative patients.Higher HBcrAg concentration was associated with younger age,HBeAg positive status,high HBV DNA loads,high level of hepatitis B surface antigen(HBsAg)and higher necroinflammation,but not with HBV genotype.Serum concentration of HBcrAg,basal core promoter/precore(BCP/PC)mutant,quantitation of HBsAg(qHBsAg)and platelet counts were independently associated with Ishak fibrosis score on multiple ordinal regression.HBV DNA was undetectable in 88.37%of patients treated with entecavir at week 72,while their level of HBcrAg was still detectable.A greater reduction in post-treatment HBcrAg concentration was associated with the regression of hepatic fibrosis and histological improvement.HBcrAg concentration>6.33 log IU/mL at baseline and logarithmic reduction>1.03 log IU/mL at week 72 were associated with a higher chance of regression of liver fibrosis and histological improvement,respectively.CONCLUSION HBcrAg level is associated with liver fibrosis progression.HBcrAg is an excellent monitor of hepatic histological changes,especially in CHB patients treated with nucleoside analogs.

High Potential Columnar Nanocrystalline AlN Films Deposited by RF Reactive Magnetron Sputtering

Columnar nanocrystalline aluminum nitride(cnc-AlN) thin films with(002) orientation and uniform texture have been deposited successfully on large silicon wafers by RF reactive magnetron sputtering.At the optimum sputtering parameters, the deposited cnc-AlN thin films show a c-axis preferred orientation with a crystallite size of about 28 nm and surface roughness(RMS) of about 1.29 nm. The cnc-AlN thin films were well transparent with an optical band gap about 4.8 e V, and the residual compressive stress and the defect density in the film have been revealed by Ramon spectroscopy. Moreover, piezoelectric performances of the cnc-AlN thin films executed effectively in a film bulk acoustic resonator structure.

License Assisted Access-WiFi Coexistence with TXOP Backoff for LTE in Unlicensed Band

License assisted access(LAA) was proposed as a solution to the challenge of satisfying high throughput requirement in cellular network with limited licensed band. LAA uses long term evolution(LTE) carrier aggregation technique to combine licensed and unlicensed bands, specifically 5 GHz Wi Fi band, in order to achieve high data rates. However, LAA has several critical concerns for services provision on 5 GHz unlicensed band. In this article, an overview of the techniques concerning the coexistence of LTE and Wi Fi on the same unlicensed band is presented. We first present several general approaches including power control of LTE evolved Node B(e NB), carrier selection, LTE duty cycling, self clear to send(CTS) and request to send/CTS(RTS/CTS), and listen before talk(LBT). Then, we focus on LBT techniques for LAA-Wi Fi coexistence and discuss how LBT based coexistence solutions can dynamically respond to the variations in network load and ensure fair coexistence in a distributed manner. Based on the LBT mechanism, we also present a fairness-aware LAA-WiF i coexisting scheme with TXOP(transmitted in a single transmission opportunity) backoff for LAA e NB. Finally, the performances of various LBT solutions for LAA-Wi Fi coexistence are evaluated using Markov chain analytical model.

Reductive damage induced autophagy inhibition for tumor therapy

Numerous therapeutic anti-tumor strategies have been developed in recent decades.However,their therapeutic efficacy is reduced by the intrinsic protective autophagy of tumors.Autophagy plays a key role in tumorigenesis and tumor treatment,in which the overproduction of reactive oxygen species(ROS)is recognized as the direct cause of protective autophagy.Only a few molecules have been employed as autophagy inhibitors in tumor therapy to reduce protective autophagy.Among them,hydroxychloroquine is the most commonly used autophagy inhibitor in clinics,but it is severely limited by its high therapeutic dose,significant toxicity,poor reversal efficacy,and nonspecific action.Herein,we demonstrate a reductive-damage strategy to enable tumor therapy by the inhibition of protective autophagy via the catalytic scavenging of ROS using porous nanorods of ceria(PN-CeO_(2))nanozymes as autophagy inhibitor.The antineoplastic effects of PN-CeO_(2)were mediated by its high reductive activity for intratumoral ROS degradation,thereby inhibiting protective autophagy and activating apoptosis by suppressing the activities of phosphatidylinositide 3-kinase/protein kinase B and p38 mitogen-activated protein kinase pathways in human cutaneous squamous cell carcinoma.Further investigation highlighted PN-CeO_(2)as a safe and efficient anti-tumor autophagy inhibitor.Overall,this study presents a reductive-damage strategy as a promising anti-tumor approach that catalytically inhibits autophagy and activates the intrinsic antioxidant pathways of tumor cells and also shows its potential for the therapy of other autophagy-related diseases.

银行卡倾斜校正研究与实现

针对银行卡自动识别系统在进行银行卡号识别时存在区域倾斜的问题,研究了一种能够对银行卡进行倾斜校正的算法.首先利用快速傅里叶变换将图像从空间域变换到频率域,计算频谱图像中的亮度直线求出倾斜角,然后使用透视变换对扭曲的图像进行校正,最后根据JNI/NDK技术将代码移植到Android平台.结果表明:在光照较弱、银行卡倾斜方式不确定的情况下,该算法较传统的倾斜校正算法均有好的效果.

Peak shrinking and interpolating for PAPR reduction in M-IFoF-based mobile fronthaul

We apply a Peak Shrinking and Interpolating(PSI)scheme to improve the Peak-to-Average Power Ratio(PAPR)performance in Multiple Intermediate-Frequency-over-Fiber(M-IFoF)based mobile fronthaul.The key idea is to detect the high peaks of the signal and shrink them,and then the shrunk peak values are interpolated into the original signal to reduce the PAPR.We also compare the PSI technique with the previous Tone-Reservation(TR)technique and Phase Pre-Distortion(PPD)technique in terms of PAPR reduction effect and computational complexity.The simulation results indicate that the PSI scheme can reduce the PAPR by more than 4.3 dB at 0.1%CCDF,which outperforms the two previous schemes with lower computational complexity.Furthermore,we find that altering M-IFoF system parameters has little effect on the performance of the PSI technique.

Combination of multi-focus Raman spectroscopy and compressive sensing for parallel monitoring of single-cell dynamics

To overcome the low efficiency of conventional confocal Raman spectroscopy,many efforts have been devoted to parallelizing the Raman excitation and acquisition,in which the scattering from multiple foci is projected onto different locations on a spectrometer's CCD,along either its vertical,horizontal dimension,or even both.While the latter projection scheme relieves the limitation on the row numbers of the CCD,the spectra of multiple foci are recorded in one spectral channel,resulting in spectral overlapping.Here,we developed a method under a com-pressive sensing framework to demultiplex the superimposed spectra of multiple cells during their dynamic processes.Unlike the previous methods which ignore the information connection be-tween the spectra of the cells recorded at different time,the proposed method utilizes a prior that a cell's spectra acquired at different time have the same sparsity structure in their principal components.Rather than independently demultiplexing the mixed spectra at the individual time intervals,the method demultiplexes the whole spectral sequence acquired continuously during the dynamic process.By penalizing the sparsity combined from all time intervals,the collaborative optimization of the inversion problem gave more accurate recovery results.The performances of the method were substantiated by a 1D Raman tweezers array,which monitored the germination of multiple bacterial spores.The method can be extended to the monitoring of many living cells randomly scattering on a coverslip,and has a potential to improve the throughput by a few orders.

Realization of UAV Routing Protocol Evaluation System Based on Game Theory Comprehensive Weighting

Aiming at the issue of the selectivity of routing protocols between UAV groups, a comprehensive weighting evaluation system based on game theory is proposed. Taking network simulation data as an example, three protocols, AODV, DSDV, and OLSR, are selected as the research objects. The results show that the DSDV protocol is suitable for the simple communication environment between UAV groups, the AODV protocol is suitable for the complex communication environment between UAV groups. In addition, the evaluation system is compared with the two evaluation systems of the Covariance Analytic Hierarchy Process (Cov-AHP) and the entropy method to calculate the relative deviation. The comparison results show that the new evaluation system is more reasonable than the other two evaluation systems.

Characteristics of Bragg Gratings in All-Solid Photonic Bandgap Fiber

We report on fiber Bragg gratings in all-solid photonie bandgap fiber that was composed of a triangular array of high-index Ge-doped rods in pure silica background with fluorine-doped index-depressed layer surrounding the Ge-doped rod. Fiber Bragg gratings were photowritten with 193 nm ArF excimer laser and characterized for their response to strain, temperature, bending, and torsion. These gratings couple light from the forward core mode to not only backward core mode but also backward rod modes. This results in multiple resonance peaks in the reflection spectrum. All resonance wavelengths exhibited the same temperature and strain response with coefficient similar to that of Bragg gratings in standard single-mode fiber. The strength of the resonance peaks corresponding to the backward rod modes showed high sensitivity to bending and torsion.

6G无线空口传输技术研究进展与展望

自20世纪80年代以来,移动通信已彻底改变世界,对人们的生活产生了深远影响.在5G成功商用的今天,人们又开始思考6G会是什么样子.作为下一代移动通信系统,6G不仅在频谱效率、时延、可靠性等通信KPI指标上提出了更高的要求,其内涵也将涉及人工智能、感知等新元素,远超传统意义上移动通信的范畴.为了实现6G愿景,迫切需要业界研究与之相适应的先进无线技术方案.本文重点介绍了6G无线空口多个研究方向的技术趋势和进展,包括信道编码技术、多址和波形技术、智能超表面技术、智能MIMO(multiple input multiple output)技术等,提出并初步验证了一系列创新技术点,如便车码、格码多址等.这些创新技术的提出,对6G愿景和KPI指标的实现起到有力的支撑作用.

基于深度学习的帕金森疾病多病程诊断网络模型

帕金森(Parkinson’s Disease,PD)是一种神经退行性疾病。当出现明显临床特征时,超过60%的黑质神经元已经发生不可逆的退化,早期疾病的诊断尤为关键,但疾病早期的诊断存在特异性不强、特征不明显等问题。因此,本文提出一种基于深度学习的帕金森疾病辅助诊断系统。首先,运用图像分割和生成对抗网络对原始图像进行分割和扩容;其次,引入多尺度卷积和注意力机制改进MobileNetV2网络,对PD、正常组以及特征不明显的前驱体的多病程诊断任务中,诊断准确率达到了92.4%,精确度达到91.7%,召回率达到92.4%,模型表现优于其他经典网络模型,且更聚焦帕金森病理学特征区域,具有更准确可靠的临床诊断效能。

Distribution of per-and polyfluoroalkyl substances in blood,serum,and urine of patients with liver cancer and associations with liver function biomarkers

Studies have shown that per-and polyfluoroalkyl substances(PFASs)may be hepatotoxic in animals or humans.However,data on clinical epidemiology are very limited.In this study,21PFASs were determined in patients with liver diseases,with the highest median concentrations detected in the serum sample(26.7 ng/mL),followed by blood(10.7 ng/mL)and urine(5.02 ng/mL).Higher total PFAS concentrations were found in hepatocellular carcinoma(HCC)patients compared to non-HCC patients,with significant discrepancies in serum and blood samples.Besides,significant correlations were also found among PFAS concentrations and age,gender,body mass index(BMI),and liver function biomarkers levels.For example,PFAS concentrations are significantly higher in males than in females;Several serum PFASs concentrations increase with age and BMI,while the serum perfluorohexane sulfonic acid(PFHxS)concentrations are negatively correlated with age.In addition,multiple regression models adjusted for age,gender and BMI found that increased serum perfluorobutane sulfonic acid(PFBS),perfluoroheptane sulfonic acid(PFHpS)and perfluorohexylphosphonic acid(PFHxPA)conentrations are correlated with elevated alkaline phosphatase(ALP),aspartate aminotransferase(AST),and alpha-fetoprotein(AFP)(p<0.05).Our results provide epidemiological support for the future study on the potential clinical hepatotoxicity of PFAS.

Urinary concentrations of phenols, oxidative stress biomarkers and thyroid cancer: Exploring associations and mediation effects

Phenols have been shown to influence the cellular proliferation and function of thyroid in experimental models. However, few human studies have investigated the association between phenol exposure and thyroid cancer, and the underlying mechanisms are also poorly understood. We conducted a case-control study by age- and sex-matching 143 thyroid cancer and 224 controls to investigate the associations between phenol exposures and the risk of thyroid cancer, and further to explore the mediating role of oxidative stress. We found that elevated urinary triclosan (TCS), bisphenol A (BPA) and bisphenol S (BPS) levels were associated with increased risk of thyroid cancer (all P for trends < 0.05), and the adjusted odds ratios (ORs) comparing the extreme exposure groups were 3.52 (95% confidence interval (CI):2.08, 5.95), 2.06 (95% CI: 1.06, 3.97) and 7.15 (95% CI: 3.12, 16.40), respectively. Positive associations were also observed between urinary TCS, BPA and BPS and three oxidative stress biomarkers measured by 8-hydroxy-2 -deoxyguanosine (8-OHdG), 8-iso-prostaglandin F(8-iso PGF) and 4-hydroxy-2-nonenal-mercapturic acid (HNE-MA), as well as between urinary 8-iso PGFand HNE-MA and the risk of thyroid cancer. Mediation analysis showed that urinary 8-iso PGFmediated 28.95%, 47.06% and 31.08% of the associations between TCS, BPA and BPS exposures and the risk of thyroid cancer, respectively (all P < 0.05). Our results suggest that exposure to TCS, BPA and BPS may be associated with increased risk of thyroid cancer and lipid peroxidation may be an intermediate mechanism. Further studies are warranted to confirm the findings.

Machine learning and theoretical analysis release the non-linear relationship among ozone,secondary organic aerosol and volatile organic compounds

Fine particulate matter(PM_(2.5))and ozone(O_(3))pollutions are prevalent air quality issues in China.Volatile organic compounds(VOCs)have significant impact on the formation of O_(3)and secondary organic aerosols(SOA)contributing PM_(2.5).Herein,we investigated 54 VOCs,O_(3)and SOA in Tianjin from June 2017 to May 2019 to explore the non-linear relationship among O_(3),SOA and VOCs.The monthly patterns of VOCs and SOA concentrations were characterized by peak values during October to March and reached a minimum from April to September,but the observed O_(3)was exactly the opposite.Machine learning methods resolved the importance of individual VOCs on O_(3)and SOA that alkenes(mainly ethylene,propylene,and isoprene)have the highest importance to O_(3)formation;alkanes(C_(n),n≥6)and aromatics were the main source of SOA formation.Machine learning methods revealed and emphasized the importance of photochemical consumptions of VOCs to O_(3)and SOA formation.Ozone formation potential(OFP)and secondary organic aerosol formation potential(SOAFP)calculated by consumed VOCs quantitatively indicated that more than 80%of the consumed VOCs were alkenes which dominated the O_(3)formation,and the importance of consumed aromatics and alkenes to SOAFP were 40.84%and 56.65%,respectively.Therein,isoprene contributed the most to OFP at 41.45%regardless of the season,while aromatics(58.27%)contributed the most to SOAFP in winter.Collectively,our findings can provide scientific evidence on policymaking for VOCs controls on seasonal scales to achieve effective reduction in both SOA and O_(3).

A high-concentrated and nonflammable electrolyte for potassium ion-based dual-graphite batteries

Potassium ion-based dual-graphite batteries(KDGBs)emerge as promising devices for large-scale applications due to their high voltage,low cost,environmental friendliness.However,conventional KPF6/carbonate-based electrolytes suffer from severe oxidation decomposition,low concentration,flammability,which limit the capacity and cyclability of KDGBs.Herein,a nonflammable potassium bis(fluorosulfonyl)imide/triethyl phosphate(KFSI/TEP)electrolyte was designed for KDGBs.When the salt-to-solvent molar ratio increases to 1:1.3,graphite cathode operated at the cut-off potential of 5.2 V exhibits much enhanced capacity,excellent rate capability(26.4 mAh∙g^(−1) at 1.0 A∙g^(−1)),superior cyclability with 98%capacity retention after 350 cycles.Inorganic compounds-rich electrode/electrolyte interphase layers derived from the preferential decomposition of FSI−anions ensure good compatibility of the 1:1.3 KFSI/TEP electrolyte with K metal and graphite anodes.Based on this electrolyte,asassembled KDGBs show high operation voltage of 4.3 V and good cycling performance.This work provides feasibility for developing long-life and safe-operation DGBs.