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National Science Review 2024年第4期11卷 111-122页

作者： rui Zhang qi Meng Zhi-Ming Ma Academy of Mathematics and Systems Science Chinese Academy of Sciences(CAS) Microsoft Research

Neural operators have been explored as surrogate models for simulating physical systems to overcome the limitations of traditional partial differential equation(PDE) solvers. However, most existing operator learning methods assume that the data originate from a single physical mechanism, limiting their applicability and performance in more realistic scenarios. To this end, we propose the physical invariant attention neural operator(PIANO) to decipher and integrate the physical invariants for operator learning from the PDE series with various physical mechanisms. PIANO employs self-supervised learning to extract physical knowledge and attention mechanisms to integrate them into dynamic convolutional *** to existing techniques, PIANO can reduce the relative error by 13.6%–82.2% on PDE forecasting tasks across varying coefficients, forces or boundary conditions. Additionally, varied downstream tasks reveal that the PI embeddings deciphered by PIANO align well with the underlying invariants in the PDE systems, verifying the physical significance of PIANO.

关键词： neural operator PDE solver contrastive learning physical invariants

Dynamic analysis of tethered defunct satellites with solar panels

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Astrodynamics 2024年第2期8卷 297-309页

作者： rui qi Yang Zhang Heng Jiang rui Zhong School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China School of Aerospace Astronautics Beihang UniversityBeijing 100191China

A precise dynamic model for towing and removing a defunct satellite with solar panels in orbit using a tethered net often has low computational efficiency owing to the complex contact and collision between the net and panels,which is not conducive to *** solve this problem,a“single main tether–multiple subtether”bifurcation structure with beads was employed as the tethered net *** study investigated the dynamics of tethered defunct satellites with solar panels,particularly the behavior of the attitude of the tethered satellite,oscillation of the main tether,and vibration of solar panels under different *** results showed that different attachment configurations of the subtethers and the flexibility of the main tether have an evident impact on the dynamic characteristics of the system.

关键词： space debris flexible solar panels tethered towing Kane’s method dynamics modeling

Should we perform sigmoidoscopy for colorectal cancer screening in people under 45 years?

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World Journal of Gastrointestinal Oncology 2024年第4期16卷 1248-1255页

作者： Waiian Leong Jia-qi Guo Chun Ning Fei-Fei Luo rui Jiao dong-Ye Yang Division of Gastroenterology&Hepatology The University of Hong Kong-Shenzhen HospitalShenzhen 518053Guangdong ProvinceChina Department of Accident&Emergency The University of Hong Kong-Shenzhen HospitalShenzhen 518053Guangdong ProvinceChina Department of Anatomical Pathology The University of Hong Kong-Shenzhen HospitalShenzhen 518053Guangdong ProvinceChina Endoscopy Center The University of Hong Kong-Shenzhen HospitalShenzhen 518053Guangdong ProvinceChin

BACKGROUND The strategy for preventing colorectal cancer is screening by colonoscopy,which offers a direct way for detection and removal of adenomatous polyps(APs).American College of Gastroenterology guidelines recommend that people aged≥45 years should undergo colonoscopy;however,how to deal with people aged≤45 years is still *** To compare the prevalence of APs and high-grade neoplasia between the left and right colon in patients≤45 *** A retrospective observational study was conducted at a single tertiary III hospital in *** study included patients aged 18-45 years with undergoing initial colonoscopy dissection and pathological diagnosis AP or high-grade neoplasia between February 2014 and January *** number of APs in the entire colon while screening and post-polypectomy surveillance in following 1-3 years were *** A total of 3053 cases were *** prevalence of APs in the left and right colon was 55.0%and 41.6%,respectively(OR 1.7,95%CI 1.6-2.4;P3 polyps(14.1%;OR 0.3,95%CI 0.1-0.6;P<0.05).CONCLUSION This study suggests that flexible sigmoidoscopy would be an optimal approach for initial screening in people aged≤45 years and would be a more cost-effective and safe strategy.

关键词： Adenomatous polyps High-grade neoplasia Colonoscopy Flexible sigmoidoscopy

Identifying the best common factor model via exploratory eactor analysis

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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 24-33页

作者： HE Bao-hua TANG rui TAGN qi-yi School of Big Data Fuzhou University of International Studies and TradeFuzhou 350202China School of Mathematics Sun Yat-Sen UniversityGuangzhou 510275China Department of Computer Science University of BathUK Institute of Insect Science Zhejiang UniversityHangzhou 310058China.

Currently,there is no solid criterion for judging the quality of the estimators in factor *** paper presents a new evaluation method for exploratory factor analysis that pinpoints an appropriate number of factors along with the best method for factor *** proposed technique consists of two steps:testing the normality of the residuals from the fitted model via the Shapiro-Wilk test and using an empirical quantified index to judge the quality of the factor *** are presented to demonstrate how the method is implemented and to verify its effectiveness.

关键词： factor analysis Shapiro-Wilk normality residuals

Feature-aided pose estimation approach based on variational auto-encoder structure for spacecrafts

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Chinese Journal of Aeronautics 2024年第8期37卷 329-341页

作者： Yanfang LIU rui ZHOU Desong DU Shuqing CAO Naiming qi Department of Aerospace Engineering Harbin Institute of TechnologyHarbin 150001China Suzhou Research Institute of HIT Suzhou 215104China Shanghai Institute of Spaceflight Control Technology Shanghai 201109China Shanghai Key Laboratory of Aerospace Intelligent Control Technology Shanghai 201109China

Real-time 6 Degree-of-Freedom(DoF)pose estimation is of paramount importance for various on-orbit *** from the development of deep learning,Convolutional Neural Networks(CNNs)in feature extraction has yielded impressive achievements for spacecraft pose *** improve the robustness and interpretability of CNNs,this paper proposes a Pose Estimation approach based on Variational Auto-Encoder structure(PE-VAE)and a Feature-Aided pose estimation approach based on Variational Auto-Encoder structure(FA-VAE),which aim to accurately estimate the 6 DoF pose of a target *** methods treat the pose vector as latent variables,employing an encoder-decoder network with a Variational Auto-Encoder(VAE)*** enhance the precision of pose estimation,PE-VAE uses the VAE structure to introduce reconstruction mechanism with the whole ***,FA-VAE enforces feature shape constraints by exclusively reconstructing the segment of the target spacecraft with the desired *** evaluation against leading methods on public datasets reveals similar accuracy with a threefold improvement in processing speed,showcasing the significant contribution of VAE structures to accuracy enhancement,and the additional benefit of incorporating global shape prior features.

关键词： Pose estimation Variational auto-encoder Feature-aided Pose Estimation Approach On-orbit measurement tasks Simulated and experimental dataset

Light/pH dual-responsive magnetic metal-organic frameworks composites for phosphorylated peptide enrichment

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Chinese Chemical Letters 2024年第7期35卷 222-226页

作者： rui Wang He qi Haijiao Zheng qiong Jia College of Chemistry Jilin UniversityChangchun 130012China Key Laboratory for Molecular Enzymology and Engineering of Ministry of Education School of Life SciencesJilin UniversityChangchun 130012China

Metal-organic frameworks(MOFs)combined with specific ligands are highly adaptable smart materials that can respond to external and physiological *** this study,we introduced a pyridinyl zwitterionic ligand with light/pH dual response into magnetic MOF composite(Fe_(3)O_(4)@ZW-MOF)for enrichment of phosphorylated peptides for the first *** introduction of the developed ligand gives MOF material dual response *** stimulation affects the generation/disappearance of free radicals of the pyridine derivative,resulting in a change in the charge gradient of the zwitterion,and zwitterion can also regulate the p H of the solution by adding acid or ***,the reversible capture and release of phosphorylated peptides can be easily achieved by adjusting light and *** established phosphorylated peptide enrichment platform exhibits high sensitivity(detection limit of 1 fmol),high selectivity(β-casein:BSA,1:1000),and good reusability(7 cycles).In addition,the method was applied to the enrichment of phosphorylated peptides in complex systems(non-fat milk and human serum),demonstrating the feasibility of this method for phosphoproteom *** conclusion,the synthesized Fe_(3)O_(4)@ZW-MOF is a promising MOF material,which provides the possibility to advance the application of responsive MOFs materials in proteomics.

关键词： Light pH Dual-response Metal-organic frameworks Phosphorylated peptide

Long-term outcome of patients with atrial myxoma after surgical intervention: analysis of 403 cases

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Journal of Geriatric Cardiology 2019年第4期16卷 338-343页

作者： Chen-Xi JIANG Jian-Gang WANG rui-dong qi Wei WANG Li-Jian GAO Jing-Hua ZHAO Chun-Xiao ZHANG Meng-Chen ZHOU Xin TU Mei-Sheng SHANG Yan YAO Department of Cardiology Beijing Anzhen HospitalCapital Medical UniversityBeijingChina Department of Cardiovascular Surgery Beijing Anzhen HospitalCapital Medical UniversityBeijingChina Center for Coronary Heart Disease Department of CardiologyCardiovascular Institute & Fuwai HospitalCAMS & PUMCNational Center for Heart DiseaseBeijingChina College of Life Science and Technology Huazhong University of Science and TechnologyWuhanChina

Objective To assess long-term survival and late cardiovascular events in patients with atrial myxoma after surgical intervention. Methods Retrospective analysis of 403 patients undergoing resection of atrial myxoma from January 2002 to December 2016 was conducted with a median follow-up period of 4.5 (range: 0.5?15) years. Results The cross-clamp time and cardiopulmonary bypass times were 41.1 ± 21.4 and 65.2 ± 27.3 min,respectively. A diagnosis of myxoma was histopathologically confirmed in all cases. The early in-hospital mortality rate was 0.7%(n = 3). During the follow-up period,tumor recurrence occurred in six patients and cerebral infarction in nine. There were 48 (11.9%) patients with late onset atrial fibrillation (AF). By multivariate analysis,age (HR = 1.05,95% CI: 1.02–1.09,P < 0.001),left atrial diameter (HR = 1.23,95% CI: 1.08–1.36,P = 0.012),and mitral valve surgery (HR = 1.17,95% CI: 1.05–1.29,P = 0.027) were independent predictors of late onset AF. Twenty-one (5.2%) patients died during the follow-up period. Advanced age (HR = 1.07,95% CI: 1.04–1.10,P = 0.003) and multiple surgical procedures (HR = 1.18,95% CI: 1.06–1.29,P = 0.012) were significantly associated with overall mortality. Conclusions Atrial myxoma can be resected with good long-term survival. Late onset AF is common after surgery in patients with atrial myxoma. Advanced age,left atrial diameter,and mitral valve surgery were independent predictors of outcomes.

关键词： Atrial fibrillation Atrial myxoma Embolism Survival

Metal-Free Photocatalytic[4+2]Annulation of Acrylamides with 2-Benzyl-2-bromocarbonyls to Assemble Tetralin-1-carboxamides

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Chinese Journal of Chemistry 2024年第2期42卷 157-163页

作者： Weicai Li Lu Tan Yijun Chen rui Liu Zhongyu qi Shixuan Yuan Zhanwen Huang Siping Wei Xi Du dong Yi Nuclear Medicine and Molecular Imaging Key Laboratory of Sichuan Province School of PharmacySouthwest Medical UniversityLuzhouSichuan 646000China Department of Chemistry School of Basic Medical ScienceSouthwest Medical UniversityLuzhouSichuan 646000China Department of Pharmacy Affiliated HospitalSouthwest Medical UniversityLuzhouSichuan 646000China

Tetralin-1-carboxamides are frequently incorporated in myriad medicinally important ***,their existing synthetic routes not only suffer from some drawbacks such as tedious procedures,harsh reaction conditions,narrow substrate scope,low yields,and environmental problems,but are also based upon the elaboration of uneasily available non-linear tetralin ***,we describe a metal-and additive-free visible light-induced[4+2]annulation of two simple linear starting materials,namely acrylamides and 2-benzyl-2-bromocarbonyls,through a cascade C(sp^(3))-Br/C(sp^(2))-H bond cleavage,double C-C bond formation,and aromatization *** developed protocol provides a convenient,efficient,and green approach to a variety of tetralin-1-carboxamide derivatives with good functional group ***,the resulting products could also undergo the Licl-mediated mono-decarboxylative cyclization process to further furnish the architecturally novel bridged polycyclic imides with excellentcis-diastereoselectivities.

关键词： Annulation Metal-free Photoredox catalysis Tetralin-1-carboxamide Cyclic imides Synthetic methods C-C coupling Radical reactions Reaction mechanisms

Experimental study on effects of gas flow rate on soot characteristics in diffusion flames coupled with plasma

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Science China(Technological Sciences) 2024年第2期67卷 475-485页

作者： qi DanDan CHEN MingXiao TU Xin LIU dong MIIT Key Laboratory of Thermal Control of Electronic Equipment School of Energy and Power EngineeringNanjing University of Science and TechnologyNanjing 210094China Advanced Combustion Laboratory School of Energy and Power EngineeringNanjing University of Science and TechnologyNanjing 210094China Department of Electrical Engineering and Electronics University of LiverpoolLiverpool L693GJUK

This study examined the evolution of morphology and nanostructure of soot particles from the plasma-flame interaction for various gas flow *** current study used both optical diagnostic and sampling methods to explore the soot production and combustion *** particles were characterized at the same positions downstream from the flame zone by thermophoretic sampling and transmission electron ***,X-ray diffraction analysis,and thermogravimetric analysis were performed to study the nanostructure and oxidation reactivity of soot.A reduction in soot concentration was found with the plasma addition,which illustrated an inhibition effect of plasma on soot *** increased gas flow rate promoted soot concentration since a growing number of carbons participated in the combustion *** on the gas flow rate(carbon content)variation and plasma activation,either liquid-like soot material with irregularly shaped protrusions or chain-like structure,or a mixture of both,were generated from the diffusion *** soot produced by plasma-flame interaction also demonstrated a high correlation between nanostructure and *** soot from lower carbon content with plasma activation had a shorter fringe length and larger fringe tortuosity related to higher oxidation *** the contrary,soot from the highest carbon content without plasma-flame interaction exhibited prevalent fullerene-like nanostructures with evident large or small shells and also had a higher carbonization degree resulting in lower oxidation reactivity.

关键词： soot characteristics gas flow rate plasma diffusion flames