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Acta Mathematica Sinica,English Series 2024年第4期40卷 985-999页

作者： Yi DENG qiang XIONG Shu Wei li School of Economics and Statistics Guangzhou UniversityGuangzhou 510006P.R.China

Recurrent event data are commonly encountered in many scientific fields,including biomedical studies,clinical trials and epidemiological surveys,and many statistical methods have been proposed for their *** this paper,we consider to use a weighted composite endpoint of recurrent and terminal events,which is weighted by the severity of each event,to assess the overall effects of covariates on the two types of events.A flexible additive-multiplicative model incorporating both multiplicative and additive effects on the rate function is proposed to analyze such weighted composite event process,and more importantly,the dependence structure among the recurrent and terminal events is left *** the estimation,we construct the unbiased estimating equations by virtue of the inverse probability weighting technique,and the resulting estimators are shown to be consistent and asymptotically normal under some mild regularity *** evaluate the finite-sample performance of the proposed method via simulation studies and apply the proposed method to a set of real data arising from a bladder cancer study.

关键词： Additive-multiplicative rates model estimating equation recurrent events terminal event weighted composite endpoint

Rapid determination of radon monitor＇s calibration factors

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Nuclear Science and Techniques 2016年第5期27卷 188-192页

作者： zhi-qiang li De-Tao Xiao Gui-zhi Zhao Xi-Jun Wu Jian Shan Qing-zhi Zhou Zheng-Zhong He University of South China Hengyang 421001 China Hengyang Normal University Hengyang 421008 China

The monitors used to measure radon concentration must be calibrated,and the calibration factor of each measurement cycle should be ***,the determination time of calibration factors of NRL-Ⅱ radon monitors should be *** this study,a method is proposed to determine the calibration factors of radon monitors *** the proposed method,the calibration factor is initially determined in the 60-min measurement cycle;the calibration factor is then identified in the other measurement cycle on the basis of the principle that the calibration factor of the same radon monitor in different measurement cycles is inversely proportional to the number of a particles produced by ^(218)Po decay in this *** demonstrate that the calculated calibration factor of the different measurement cycles is consistent with the experimental calibration ***,this method is reliable and can be used to determine the calibration factor of radon monitors rapidly.

关键词：校准因子氡浓度监测仪快速测定测量周期监测器测定时间校正因子

Oxidation resistant low-alloyed Ti alloys with good ductility

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Rare Metals 2024年第8期43卷 3921-3936页

作者： Meng li Zhang-zhi Shi Jun-Yi Xu Fu-zhi Dai Xiang-Min li Zi-lin li Lu-Ning Wang Beijing Advanced Innovation Center for Materials Genome Engineering State Key Laboratory for Advance Metals and MaterialsSchool of Materials Science and Engineering University of Science and Technology Beijing Institute of Materials Intelligent Technology Liaoning Academy of Materials

Oxidation resistance enhancement of pure Ti often comes at the cost of reduced ductility,which is frequently the problem through alloying with sole Al,Si,W,Mo and *** overcome the short coming of single element alloying,this paper proposes a multi-element low-alloying strategy to take advantage of synergistic effects and resolve the conflict between oxidation resistance and *** demonstrates that the addition of a small quantity of Ta（0.51wt%） can boost both oxidation resistance and ductility in comparison to pure ***,the combined addition of a small amount（0.54 wt%） of Ta,Nb and Si not only preserves good ductility of pure Ti,but also reduces mass gains to 14%-67% of pure Ti during 100 h oxidation at 650-850℃ in *** indicates even better oxidation resistance than that obtained through the use of Ta,Nb,or Nb+Ta *** Ta+Nb+Si alloying creates an oxide layer that is less porous and more resistant to stratification and ***,a 3-μm N-rich layer can form in the Ti substrate beneath the oxide scale,in which phase transformation generates coherent Ti2N with（0001）Tias the habit plane,with N atoms prefers to diffuse along ■ than along [0001]*** completely transformed Ti2N region or partially transformed Ti+Ti2N region can effectively impede oxygen ***,the multielement low-alloying strategy is promising for enhancing both oxidation resistance and mechanical properties of metallic materials in the future.

关键词： Ti alloys Multi-element Co-alloying Oxidation resistance Mechanical properties

A robust tensor watermarking algorithm for diffusion-tensor images

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Frontiers of Information Technology & Electronic Engineering 2024年第3期25卷 384-397页

作者： Chengmeng liU zhi li Guomei WANG Long ZHENG State Key Laboratory of Public Big Data College of Computer Science and TechnologyGuizhou UniversityGuiyang 550025China

Watermarking algorithms that use convolution neural networks have exhibited good robustness in studies of deep learning ***,after embedding watermark signals by convolution,the feature fusion eficiency of convolution is relatively low;this can easily lead to distortion in the embedded *** distortion occurs in medical images,especially in diffusion tensor images(DTIs),the clinical value of the DTI is *** address this issue,a robust watermarking algorithm for DTIs implemented by fusing convolution with a Transformer is proposed to ensure the robustness of the watermark and the consistency of sampling distance,which enhances the quality of the reconstructed image of the watermarked DTIs after embedding the watermark *** the watermark-embedding network,Ti-weighted(Tlw)images are used as prior *** correlation between T1w images and the original DTI is proposed to calculate the most significant features from the T1w images by using the Transformer *** maximum of the correlation is used as the most significant feature weight to improve the quality of the reconstructed *** the watermark extraction network,the most significant watermark features from the watermarked DTI are adequately learned by the Transformer to robustly extract the watermark signals from the watermark *** results show that the average peak signal-to-noise ratio of the watermarked DTI reaches 50.47 dB,the diffusion characteristics such as mean diffusivity and fractional anisotropy remain unchanged,and the main axis deflection angleαAc is close to *** proposed algorithm can effectively protect the copyright of the DTI and barely affects the clinical diagnosis.

关键词： Robust watermarking algorithm Transformer Image reconstruction Diffusion tensor images Soft attention Hard attention Tl-weighted images

Curcumin inhibits the growth and invasion of gastric cancer by regulating long noncoding RNA AC022424.2

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World Journal of Gastrointestinal Oncology 2024年第4期16卷 1437-1452页

作者： Bin-Sheng Wang Chen-li Zhang Xiang Cui qiang li Lei Yang zhi-Yun He Ze Yang Miao-Miao Zeng Nong Cao Department of General Surgery First Hospital of Lanzhou UniversityLanzhou 730000Gansu ProvinceChina School of Basic Medical Sciences Lanzhou UniversityLanzhou 730000Gansu ProvinceChina Third Department of General Surgery First Hospital of Lanzhou UniversityLanzhou 730000Gansu ProvinceChina

BACKGROUND Gastric cancer,characterized by a multifactorial etiology and high heterogeneity,continues to confound researchers in terms of its ***,a natural anticancer agent,exhibits therapeutic promise in gastric *** effects include promoting cell apoptosis,curtailing tumor angiogenesis,and enhancing sensitivity to radiation and *** noncoding RNAs(lncRNAs)have garnered significant attention as biomarkers for early screening,diagnosis,treatment,and drug response because of their remarkable specificity and *** investigations have revealed an association between aberrant lncRNA expression and early diagnosis,clinical staging,metastasis,drug sensitivity,and prognosis in gastric cancer.A profound understanding of the intricate mechanisms through which lncRNAs influence gastric cancer develop-ment can provide novel insights for precision treatment and tailored management of patients with gastric *** study aimed to unravel the potential of curcumin in suppressing the malignant behavior of gastric cancer cells by upregu-lating specific lncRNAs and modulating gastric cancer onset and *** To identify lncRNAs associated with curcumin treatment and investigate the role of lncRNA AC022424.2 in the effects of curcumin on gastric cancer cell apoptosis,proliferation,and ***,these findings were validated in clinical *** The study employed CCK-8 assays to assess the impact of curcumin on gastric cancer cell proliferation,flow cytometry to investigate its effects on apoptosis,and scratch and Transwell assays to evaluate its influence on the migration and invasion of BGC-823 and MGC-803 *** blotting was used to gauge changes in the protein expression levels of CDK6,CDK4,Bax,Bcl-2,caspase-3,P65,and the PI3K/Akt/mTOR pathway in gastric cancer cell lines after curcumin *** expression of lncRNAs before and after curcumin treatment was assessed using lncRNA seq

关键词： Gastric cancer Curcumin Long noncoding RNA AC022424.2 Apoptosis Akt/PI3K pathway Lymph metastasis

Layered multicast congestion control by particle swarm optimization in heterogeneous environment

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The Journal of China Universities of Posts and Telecommunications 2011年第3期18卷 85-91页

作者： MA Hai-yuan MENG Xiang-ru MA zhi-qiang li Jin-liang The Telecommunication Engineering Institute Air Force Engineering University Xi'an 710077 China

To enhance multicast throughput in heterogeneous environment, a new layered multicast congestion control scheme is proposed. With the goal of maximizing global satisfaction of the whole group, allocating sending rate in each layer is formulated to an optimization problem. Since the problem is noncovexity, the sender uses particle swarm optimization to search a set of optimal layers rates. The new scheme also eliminates ＇lowest-first＇ phenomenon by proposing a feedbacks suppression algorithm named equal-probability sampling （EPS）. Upon EPS all the receivers send feedbacks at equal probability without bias. Simulation results prove that the new scheme can enhance global satisfaction and multicast throughput efficiently, compared with the traditional layered multicast congestion control scheme based on representatives.

关键词： layered multicast congestion control particle swarm optimization feedbacks suppression

Torque limit-based Inertial Control Method Based on Delayed Support for Primary Frequency Control of Wind Turbines

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Journal of Modern Power Systems and Clean Energy 2024年第2期12卷 561-570页

作者： Wei Gu Zaiyu Chen Qun li Minghui Yin qiang li Yun Zou School of Automation Nanjing University of Science and TechnologyNanjing 210094China State Grid Jiangsu Electric Power Co. Ltd.Research InstituteNanjing 211103China

To avoid the secondary frequency dip caused by the steep drop of the electrical power of wind turbines(WTs)at the end of frequency support stage,the torque limit-based iner-tial control(TliC)method sets the power reference as a linear function of rotor speed,rather than the step form for the step-wise inertial ***,the compensation effect on the frequency nadir(FN)caused by the load surge is weakened as the TliC power is no longer in the step ***,the maximum point of the frequency response component(FRC)contributed by TliC occurs earlier than the minimum point of FRC corresponding to the load surge,so that the FN cannot be adequately ***,this paper first investigates the relation between the peak and nadir times of FRCs stimulated by the TliC and load *** this basis,with the compensation principle of matching the peak and nadir times of FRCs,the improved TliC method based on delayed support is ***,the effectiveness of the proposed method is validated via the experiments on the test bench of wind-integrated power system.

关键词： Wind turbine frequency response component torque limit inertial control delayed support

Improving Fatigue Properties of 316L Stainless Steel Welded Joints by Surface Spinning Strengthening

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Acta Metallurgica Sinica(English Letters) 2024年第5期37卷 840-854页

作者： Dongqiqiong Wang qiang Wang Xiaowu li Zhefeng Zhang Department of Materials Physics and Chemistry School of Materials Science and Engineeringand Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education)Northeastern UniversityShenyang 110819China Shi-Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China College of light Industry Liaoning UniversityShenyang 110036China

The surface spinning strengthening(3S)mechanism and fatigue life extension mechanism of 316L stainless steel welded joint were systematically elucidated by microstructural analyses and mechanical *** indicate that surface gradient hardening layer of approximately 1 mm is formed in the base material through grain fragmentation and deformation twin strengthening,as well as in the welding zone composed of deformedδ-phases and *** fatigue strength of welded joint after 3S significantly rises by 32%(from 190 to 250 MPa),which is attributed to the effective elimination of surface geometric defects,discrete refinement ofδ-Fe phases and the appropriate improvement in the surface strength,collectively mitigating strain localization and surface fatigue damage within the gradient strengthening *** redistributed fineδ-Fe phases benefited by strong stress transfer of 3S reduce the risk of surface weak phase cracking,causing the fatigue fracture to transition from microstructure defects to crystal defects dominated by slip,further suppressing the initiation and early propagation of fatigue cracks.

关键词： 316L stainless steel Welded joint Surface spinning strengthening Nanotwin Fatigue life

Enhanced photocatalytic performance by regulating the Ce^(3+)/Ce^(4+)ratio in cerium dioxide

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Frontiers of Chemical Science and Engineering 2024年第3期18卷 75-87页

作者： zhi li Dongsheng Jia Wei Zhang Ying li Mitang Wang Dongliang Zhang School of Materials and Chemistry University of Shanghai for Science and TechnologyShanghai200093China

Cerium dioxide(CeO_(2))photocatalysts are used in treating environmental pollution and addressing the energy crisis due to their excellent oxygen storage capacities and abundant oxygen *** this paper,CeO_(2)precursors were synthesized with different water-alcohol ratios via a solvothermal method,and CeO_(2)photocatalysts with different Ce^(3+)/Ce^(4+)ratios were obtained by changing the precursor calcination atmospheres(air,Ar)as well as the calcination *** effects of CeO_(2)with different Ce^(3+)/Ce^(4+)ratios in photocatalytic degradations of methylene blue under visible light were investigated.X-ray photoelectron spectroscopy results showed that the surfaces of the samples calcined under Ar had higher Ce^(3+)/Ce^(4+)ratios and oxygen vacancy concentrations,which reduced the band gaps of the catalysts and improved their utilization of visible *** addition,the many Ce^(3+)/Ce^(4+)redox centers and oxygen vacancies on the sample surfaces improved the separation and transfer efficiencies of the photogenerated *** sample C2-Ar calcined under Ar showed a high adsorption capacity and excellent photocatalytic activity by removing 96%of the methylene blue within 120 min,which was more than twice the degradation rate of the sample(C2-air)prepared via calcination under *** experiments showed that photogenerated holes played a key role in the photocatalytic *** addition,a synergistic photocatalytic mechanism for the Ce^(3+)/Ce^(4+)redox centers and oxygen vacancies was elucidated in detail,and the sensitization of cerium dioxide by dyes aided the degradation of methylene blue.

关键词： CeO_(2) oxygen vacancies Ce^(3+)/Ce^(4+)ratios photocatalytic dye-sensitization

Severe pediatric COVID‑19:a review from the clinical and immunopathophysiological perspectives

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World Journal of Pediatrics 2024年第4期20卷 307-324页

作者： Yi‑Kan Sun Can Wang Pei‑Quan lin Lei Hu Jing Ye zhi‑Gang Gao Ru lin Hao‑Min li qiang Shu li‑Su Huang lin‑Hua Tan Children's Hospital Zhejiang University School of MedicineHangzhou 310052China The Second Affiliated Hospital Zhejiang University School of MedicineHangzhou 310030China Surgical Intensive Care Unit Children’s HospitalZhejiang University School of MedicineHangzhou 310052China Department of General Surgery Children’s HospitalZhejiang University School of MedicineHangzhou 310052China Department of Cardiopulmonary and Extracorporeal life Support Children’s HospitalZhejiang University School of MedicineHangzhou 310052China Clinical Data Center Children’s HospitalZhejiang University School of MedicineHangzhou 310052China Department of Cardiac Surgery Children’s HospitalZhejiang University School of MedicineHangzhou 310052China National Clinical Research Center for Child Health Children’s HospitalZhejiang University School of MedicineHangzhou 310052China Department of Infectious Diseases Children’s HospitalZhejiang University School of MedicineHangzhou 310052China

Background Coronavirus disease 2019(COVID-19)tends to have mild presentations in ***,severe and critical cases do arise in the pediatric population with debilitating systemic impacts and can be fatal at times,meriting further attention from ***,the intricate interactions between the pathogen virulence factors and host defense mechanisms are believed to play indispensable roles in severe COVID-19 pathophysiology but remain incompletely *** sources A comprehensive literature review was conducted for pertinent publications by reviewers independently using the PubMed,Embase,and Wanfang *** keywords included“COVID-19 in children”,“severe pediatric COVID-19”,and“critical illness in children with COVID-19”.Results Risks of developing severe COVID-19 in children escalate with increasing numbers of co-morbidities and an unvaccinated *** respiratory distress stress and necrotizing pneumonia are prominent pulmonary manifestations,while various forms of cardiovascular and neurological involvement may also be *** immunological processes are implicated in the host response to COVID-19 including the type I interferon and inflammasome pathways,whose dysregulation in severe and critical diseases translates into adverse clinical *** inflammatory syndrome in children(MIS-C),a potentially life-threatening immune-mediated condition chronologically associated with COVID-19 exposure,denotes another scientific and clinical conundrum that exemplifies the complexity of pediatric *** the considerable dissimilarities between the pediatric and adult immune systems,clinical trials dedicated to children are lacking and current management recommendations are largely adapted from adult *** Severe pediatric COVID-19 can affect multiple organ *** dysregulated immune pathways in severe COVID-19 shape the disease course,epitomize the vast functional diversity of the

关键词： Immunopathophysiology MIS-C Pediatric critical care Severe pediatric COVID-19