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On convergence of covariance matrix of empirical Bayes hyper-parameter estimator

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Control Theory and Technology 2024年第2期22卷 149-162页

作者： Yue Ju Biqiang Mu Tianshi Chen School of data Science and Shenzhen Research Institute of Big data The Chinese University of Hong KongShenzhenShenzhen518172GuangdongChina division of Decision and Control Systems School of Electrical Engineering and Computer ScienceKTH Royal Institute of Technology10044StockholmSweden Key Laboratory of Systems and Control Institute of Systems ScienceAcademy of Mathematics and System ScienceChinese Academy of SciencesBeijing100190China

Regularized system identification has become the research frontier of system identification in the past decade.One related core subject is to study the convergence properties of various hyper-parameter estimators as the sample size goes to infinity.In this paper,we consider one commonly used hyper-parameter estimator,the empirical Bayes(EB).Its convergence in distribution has been studied,and the explicit expression of the covariance matrix of its limiting distribution has been given.However,what we are truly interested in are factors contained in the covariance matrix of the EB hyper-parameter estimator,and then,the convergence of its covariance matrix to that of its limiting distribution is required.In general,the convergence in distribution of a sequence of random variables does not necessarily guarantee the convergence of its covariance matrix.Thus,the derivation of such convergence is a necessary complement to our theoretical analysis about factors that influence the convergence properties of the EB hyper-parameter estimator.In this paper,we consider the regularized finite impulse response(FIR)model estimation with deterministic inputs,and show that the covariance matrix of the EB hyper-parameter estimator converges to that of its limiting distribution.Moreover,we run numerical simulations to demonstrate the efficacy of ourtheoretical results.

关键词： Regularized system identification Hyper-parameter estimator Empirical Bayes Convergence of covariance matrix

A scoping review of methodologies for applying artificial intelligence to physical activity interventions

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Journal of Sport and Health Science 2024年第3期13卷 428-441页

作者： Ruopeng An Jing Shen Junjie Wang Yuyi Yang Brown School Washington UniversitySt.LouisMO 63130USA Department of Physical Education China University of Geosciences BeijingBeijing 100083China School of Kinesiology and Health Promotion Dalian University of TechnologyDalian 116024China division of Computational and data Sciences Washington UniversitySt.LouisMO 63130USA

Purpose This scoping review aimed to offer researchers and practitioners an understanding of artificial intelligence(AI)applications in physical activity(PA)interventions;introduce them to prevalent machine learning(ML),deep learning(DL),and reinforcement learning(RL)algorithms;and encourage the adoption of AI methodologies.Methods A scoping review was performed in PubMed,Web of Science,Cochrane Library,and EBSCO focusing on AI applications for promoting PA or predicting related behavioral or health outcomes.AI methodologies were summarized and categorized to identify synergies,patterns,and trends informing future research.Additionally,a concise primer on predominant AI methodologies within the realm of PA was provided to bolster understanding and broader application.Results The review included 24 studies that met the predetermined eligibility criteria.AI models were found effective in detecting significant patterns of PA behavior and associations between specific factors and intervention outcomes.Most studies comparing AI models to traditional statistical approaches reported higher prediction accuracy for AI models on test data.Comparisons of different AI models yielded mixed results,likely due to model performance being highly dependent on the dataset and task.An increasing trend of adopting state-of-the-art DL and RL models over standard ML was observed,addressing complex human–machine communication,behavior modification,and decision-making tasks.Six key areas for future AI adoption in PA interventions emerged:personalized PA interventions,real-time monitoring and adaptation,integration of multimodal data sources,evaluation of intervention effectiveness,expanding access to PA interventions,and predicting and preventing injuries.Conclusion The scoping review highlights the potential of AI methodologies for advancing PA interventions.As the field progresses,staying informed and exploring emerging AI-driven strategies is essential for achieving significant improvements in PA interventions and fostering overall we

关键词： Artificial intelligence Intervention Machine learning Neural network Physical activity

On the superconvergence of a WG method for the elliptic problem with variable coefficients

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Science China Mathematics 2024年第8期 1899-1910页

作者： Junping Wang Xiaoshen Wang Xiu Ye Shangyou Zhang Peng Zhu division of Mathematical Sciences National Science Foundation Department of Mathematics University of Arkansas at Little Rock Department of Mathematical Sciences University of Delaware College of data Science Jiaxing University

This article extends a recently developed superconvergence result for weak Galerkin（WG） approximations for modeling partial differential equations from constant coefficients to variable coefficients.This superconvergence features a rate that is two orders higher than the optimal-order error estimates in the usual energy and L2norms. The extension from constant to variable coefficients for the modeling equations is highly non-trivial. The underlying technical analysis is based on a sequence of projections and decompositions. Numerical results confirm the superconvergence theory for second-order elliptic problems with variable coefficients.

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A comprehensive review of genetic causes of obesity

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World Journal of Pediatrics 2024年第1期20卷 26-39页

作者： Marcio Jose Concepcion-Zavaleta Juan Eduardo Quiroz-Aldave Maria del Carmen Durand-Vasquez Elman Rolando Gamarra-Osorio Juan del Carmen Valencia de la Cruz Claudia Mercedes Barrueto-Callirgos Susan Luciana Puelles-Leon Elena de Jesus Alvarado-Leon Frans Leiva-Cabrera Francisca Elena Zavaleta-Gutierrez Luis Alberto Concepcion-Urteaga Jose Paz-Ibarra Universidad Cientifica del Sur Bolivar 2150 AvenuePueblo Libre15084LimaPeru division of Medicine Hospital de Apoyo ChepénChepenPeru division of Family Medicine Hospital de Apoyo ChepénChepenPeru division of Endocrinology Hospital Victor Lazarte EchegarayTrujilloPeru division of Pediatrics Hospital de Apoyo ChepenChepenPeru division of Internal Medicine Hospital de Apoyo ChepenChepenPeru division of Genetics Universidad Nacional de TrujilloTrujilloPeru division of Neonatology Hospital Belen de TrujilloTrujilloPeru division of Internal Medicine Universidad Nacional de TrujilloTrujilloPeru Department of Medicine School of MedicineUniversidad Nacional Mayor de San MarcosLimaPeru

Background Obesity is a multifactorial chronic disease with a high,increasing worldwide prevalence.Genetic causes account for 7%of the cases in children with extreme obesity.data sources This narrative review was conducted by searching for papers published in the PubMed/MEDLINE,Embase and SciELO databases and included 161 articles.The search used the following search terms:"obesity","obesity and genetics","leptin","Prader-Willi syndrome",and"melanocortins".The types of studies included were systematic reviews,clinical trials,prospective cohort studies,cross-sectional and prospective studies,narrative reviews,and case reports.Results The leptin-melanocortin pathway is primarily responsible for the regulation of appetite and body weight.However,several important aspects of the pathophysiology of obesity remain unknown.Genetic causes of obesity can be grouped into syndromic,monogenic,and polygenic causes and should be assessed in children with extreme obesity before the age of 5 years,hyperphagia,or a family history of extreme obesity.A microarray study,an analysis of the melanocortin type 4 receptor gene mutations and leptin levels should be performed for this purpose.There are three therapeutic levels:lifestyle modifications,pharmacological treatment,and bariatric surgery.Conclusions Genetic study technologies are in constant development;however,we are still far from having a personalized approach to genetic causes of obesity.A significant proportion of the affected individuals are associated with genetic causes;however,there are still barriers to its approach,as it continues to be underdiagnosed.

关键词： Leptin Melanocortin Obesity Prader-Willi syndrome Precision medicine

Prostate health index can stratify patients with Prostate Imaging Reporting and data System score 3 lesions on magnetic resonance imaging to reduce prostate biopsies

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Asian Journal of Andrology 2024年第1期26卷 20-24页

作者： John Shung-Lai Leung Wai-Kit Ma Brian Sze-Ho Ho Stacia Tsun-Tsun Chun Rong Na Yongle Zhan Chi-Yuen Ng Chi-Ho Ip Ada Tsui-Lin Ng Yiu-Chung Lam division of Urology Department of SurgeryQueen Mary HospitalUniversity of Hong KongHong KongChina division of Urology Department of SurgeryPrincess Margaret HospitalHongKongChina

We aim to evaluate prostate health index as an additional risk-stratification tool in patients with Prostate Imaging Reporting and data System score 3 lesions on multiparametric magnetic resonance imaging.Men with biochemical or clinical suspicion of having prostate cancer who underwent multiparametric magnetic resonance imaging in two tertiary centers(Queen Mary Hospital and Princess Margaret Hospital,Hong Kong,China)between January 2017 and June 2022 were included.Ultrasound-magnetic resonance imaging fusion biopsies were performed after prostate health index testing.Those who only had Prostate Imaging Reporting and data System score 3 lesions were further stratified into four prostate health index risk groups and the cancer detection rates were analyzed.Out of the 747 patients,47.3%had Prostate Imaging Reporting and data System score 3 lesions only.The detection rate of clinically significant prostate cancer in this group was 15.0%.The cancer detection rates of clinically significant prostate cancer had statistically significant differences:5.3%in prostate health indexdata System score 3 lesions.Biopsies could be avoided in patients with low prostate health index,with a small risk of missing clinically significant prostate cancer.

关键词： biopsy fusion biopsy magnetic resonance imaging prostate cancer prostate health index

Effect of Plastic Deformation on Microstructure and Properties of Cu-(1 wt%-6 wt%) Ag Alloy

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Journal of Wuhan University of Technology(Materials Science) 2024年第3期39卷 747-753页

作者：茹亚东 ZHANG Zhongyuan 高召顺 ZHANG Ling ZUO Tingting XUE Jiangli TANG Zhixiang DA Bo LIU Yongsheng XIAO Liye Institute of Electrical Engineering Chinese Academy of SciencesBeijing 100190China Department of Physics Shanghai University of Electric PowerShanghai 201306China University of Chinese Academy of Sciences Beijing 100190China International Joint Labora-tory for Light Alloys(MOE) College of Materials Science and EngineeringChongqing UniversityChongqing 400044China Research and Services division of Materials data and Integrated System National Institute for Materials ScienceTsukuba 305-0047Japan

In the present study,the Cu-(1 wt%-6 wt%)Ag alloys were prepared by melting,forging and wire drawing.The effects of plastic deformation on microstructure evolution and properties of the alloys were investigated.The results show that non-equilibrium eutectic colonies exist in the Cu-(3 wt%-6 wt%)Ag alloy and no eutectic colonies in the 1 wt%-2 wt%Ag containing alloys.These eutectic colonies are aligned along the drawing direction and refined with the increase of draw ratio.Attributed to the refinement of eutectic colonies,the Cu-Ag alloy exhibits higher strength with the increase of draw ratio.The Cu-6Ag alloy exhibits excellent comprehensive properties with a strength of 930 MPa and a conductivity of 82%IACS when the draw ratio reaches 5.7.

关键词： Cu-Ag alloy high strength and high conductivity microstructure eutectic structure strengthening mechanism

Solid-state impedance spectroscopy studies of dielectric properties and relaxation processes in Na_(2)O–V_(2)O_(5)–Nb_(2)O_(5)–P_(2)O_(5) glass

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International Journal of Minerals,Metallurgy and Materials 2024年第1期31卷 186-196页

作者： Sara Marijan Luka Pavic division of Materials Chemistry Ruđer Boskovic InstituteBijenicka 54HR-10000 ZagrebCroatia

Solid-state impedance spectroscopy(SS-IS)was used to investigate the influence of structural modifications resulting from the addition of Nb2O5 on the dielectric properties and relaxation processes in the quaternary mixed glass former(MGF)system 35Na_(2)O–10V_(2)O_(5)–(55-x)P_(2)O_(5)–xNb_(2)O_(5)(x=0–40,mol%).The dielectric parameters,including the dielectric strength and dielectric loss,are determined from the frequency and temperature-dependent complex permittivity data,revealing a significant dependence on the Nb2O5 content.The transition from a predominantly phosphate glass network(xdata,show that DC conductivity and relaxation processes are governed by the same mechanism,attributed to ionic conductivity.In contrast to glasses with a single peak in frequency dependence of imaginary part of electrical modulus,M″(ω),Nb-40 glass-ceramic exhibits two distinct contributions with similar relaxation times.The high-frequency peak indicates bulk ionic conductivity,while the additional low-fre-quency peak is associated with the grain boundary effect,confirmed by the electrical equivalent circuit(EEC)modelling.The scaling characteristics of permittivity and conductivity spectra,along with the electrical modulus,validate time-temperature superposition and demonstrate a strong correlation with composition and modific

关键词： phosphate glasses glass-ceramics impedance spectroscopy dielectric properties relaxation processes permittivity scaling conductivity scaling modulus formalism

Long-term outcome of stem cell transplantation with and without anti-tumor necrotic factor therapy in perianal fistula with Crohn’s disease

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World Journal of Stem Cells 2024年第3期16卷 257-266页

作者： Min Young Park Yong Sik Yoon Jae Ha Park Jong Lyul Lee Chang Sik Yu division of Colon and Rectal Surgery Department of SurgeryYonsei University College of MedicineSeoul 03722South Korea division of Colon and Rectal Surgery Department of SurgeryUniversity of Ulsan College of MedicineAsan Medical CenterSeoul 05505South Korea

BACKGROUND Stem cell transplantation is a promising therapeutic option for curing perianal fistula in Crohn’s disease(CD).Anti-tumor necrotic factor(TNF)therapy combined with drainage procedure is effective as well.However,previous studies are limited to proving whether the combination treatment of biologics and stem cell transplantation improves the effect of fistula closure.AIM This study aimed to evaluate the long-term outcomes of stem cell transplantation and compare Crohn’s perianal fistula(CPF)closure rates after stem cell transplantation with and without anti-TNF therapy,and to identify the factors affecting CPF closure and recurrence.METHODS The patients with CD who underwent stem cell transplantation for treating perianal fistula in our institution between Jun 2014 and December 2022 were enrolled.Clinical data were compared according to anti-TNF therapy and CPF closure.RESULTS A total of 65 patients were included.The median age of females was 26 years(range:21-31)and that of males was 29(44.6%).The mean follow-up duration was 65.88±32.65 months,and complete closure was observed in 50(76.9%)patients.The closure rates were similar after stem cell transplantation with and without anti-TNF therapy(66.7%vs 81.6%at 3 year,P=0.098).The patients with fistula closure had short fistulous tract and infrequent proctitis and anorectal stricture(P=0.027,0.002,and 0.008,respectively).Clinical factors such as complexity,number of fistulas,presence of concurrent abscess,and medication were not significant for closure.The cumulative 1-,2-,and 3-year closure rates were 66.2%,73.8%,and 75.4%,respectively.CONCLUSION Anti-TNF therapy does not increase CPF closure rates in patients with stem cell transplantation.However,both refractory and non-refractory CPF have similar closure rates after additional anti-TNF therapy.Fistulous tract length,proctitis,and anal stricture are risk factors for non-closure in patients with CPF after stem cell transplantation.

关键词： Crohn’s disease Anus Fistula Stem cell transplantation Tumor necrosis factor-alpha inhibitors Infliximab

Image Fusion Using Wavelet Transformation and XGboost Algorithm

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Computers, Materials & Continua 2024年第4期79卷 801-817页

作者： Shahid Naseem Tariq Mahmood Amjad Rehman Khan Umer Farooq Samra Nawazish Faten S.Alamri Tanzila Saba Department of Information Sciences Division of S&TUniversity of EducationLahore54770Pakistan Artificial Intelligence and data Analytics(AIDA)Lab CCIS Prince Sultan UniversityRiyadh11586Saudi Arabia Faculty of Information Sciences University of EducationVehari CampusVehari61100Pakistan Department of Computer Science University of Engineering and TechnologyTaxila47050Pakistan Department of Mathematical Sciences College of SciencePrincess Nourah Bint Abdulrahman UniversityRiyadh84428Saudi Arabia

Recently,there have been several uses for digital image processing.Image fusion has become a prominent application in the domain of imaging processing.To create one final image that provesmore informative and helpful compared to the original input images,image fusion merges two or more initial images of the same item.Image fusion aims to produce,enhance,and transform significant elements of the source images into combined images for the sake of human visual perception.Image fusion is commonly employed for feature extraction in smart robots,clinical imaging,audiovisual camera integration,manufacturing process monitoring,electronic circuit design,advanced device diagnostics,and intelligent assembly line robots,with image quality varying depending on application.The research paper presents various methods for merging images in spatial and frequency domains,including a blend of stable and curvelet transformations,everageMax-Min,weighted principal component analysis(PCA),HIS(Hue,Intensity,Saturation),wavelet transform,discrete cosine transform(DCT),dual-tree Complex Wavelet Transform(CWT),and multiple wavelet transform.Image fusion methods integrate data from several source images of an identical target,thereby enhancing information in an extremely efficient manner.More precisely,in imaging techniques,the depth of field constraint precludes images from focusing on every object,leading to the exclusion of certain characteristics.To tackle thess challanges,a very efficient multi-focus wavelet decomposition and recompositionmethod is proposed.The use of these wavelet decomposition and recomposition techniques enables this method to make use of existing optimized wavelet code and filter choice.The simulated outcomes provide evidence that the suggested approach initially extracts particular characteristics from images in order to accurately reflect the level of clarity portrayed in the original images.This study enhances the performance of the eXtreme Gradient Boosting(XGBoost)algorithm in detecting brain malignancies with

关键词： Image fusion max-min average CWT XGBoost DCT inclusive innovations spatial and frequency domain