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Predicting colorectal adenomatous polyps in patients with chronic liver disease: A novel nomogram

World Journal of Gastroenterology 2025年第2期31卷 71-84页

作者： Yu-Qin li Wen-Tao Kuai lin Chen Ming-Hui Zeng Xue-Mei Tao Jia-Xin Han Yue-Kui Wang lian-Xin Xu li-Ying Ge Yong-Gang liu shuang li liang Xu Yu-Qiang Mi Clinical School of the Second People’s Hospital Tianjin Medical UniversityTianjin 300192China Department of Hepatology Tianjin Second People’s HospitalTianjin 300192China Department of Pathology Clinical School of the Second People’s HospitalTianjin 300110China Endoscopy Center Tianjin Second People’s HospitalTianjin 300192China

BACKGROUND Colorectal polyps are commonly observed in patients with chronic liver disease(CLD)and pose a significant clinical concern because of their potential for *** To explore the clinical characteristics of colorectal polyps in patients with CLD,a nomogram was established to predict the presence of adenomatous polyps(AP).METHODS Patients with CLD who underwent colonoscopy at Tianjin Second People’s Hospital from January 2020 to May 2023 were *** data including laboratory results,colonoscopy findings,and pathology reports were *** variables for the nomogram were identified through least absolute shrinkage and selection operator regression,followed by multivariate logistic *** performance of the model was evaluated using the area under the receiver area under curve,as well as calibration curves and decision curve *** The study enrolled 870 participants who underwent colonoscopy,and the detection rate of AP in patients with CLD was 28.6%.Compared to individuals without polyps,six risk factors were identified as predictors for AP occurrence:Age,male sex,body mass index,alcohol consumption,overlapping metabolic dysfunction-associated steatotic liver disease,and serum ferritin *** novel nomogram(AP model)demonstrated an area under curve of 0.801(95%confidence interval:0.756-0.845)and 0.785(95%confidence interval:0.712-0.858)in the training and validation *** curves indicated good agreement among predicted and actual probabilities(training:χ^(2)=11.860,P=0.157;validation:χ^(2)=7.055,P=0.530).The decision curve analysis underscored the clinical utility of the nomogram for predicting the risk of *** The AP model showed reasonable accuracy and provided a clinical foundation for predicting the occurrence of AP in patients with CLD,which has a certain predictive value.

关键词： Metabolic dysfunction associated steatotic liver disease Fatty liver Chronic liver disease Colorectal adenomas Hepatitis Risk factors

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Effective elastic properties of one-dimensional hexagonal quasicrystal composites

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Applied Mathematics and Mechanics(English Edition) 2021年第10期42卷 1439-1448页

作者： shuang li lianhe li College of Mathematics Science Inner Mongolia Normal UniversityHohhot 010022China

The explicit expression of Eshelby tensors for one-dimensional(1D) hexagonal quasicrystal composites is presented by using Green’s function method. The closed forms of Eshelby tensors in the special cases of spheroid, elliptic cylinder, ribbon-like,penny-shaped, and rod-shaped inclusions embedded in 1 D hexagonal quasicrystal matrices are given. As an application of Eshelby tensors, the analytical expressions for the effective properties of the 1 D hexagonal quasicrystal composites are derived based on the Mori-Tanaka method. The effects of the volume fraction of the inclusion on the elastic properties of the composite materials are discussed.

关键词： one-dimensional(1D)hexagonal quasicrystal Eshelby tensor Mori-Tanaka method

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An Erds-Ko-Rado Theorem for Restricted Signed Sets

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Acta Mathematicae Applicatae Sinica 2010年第1期26卷 107-112页

作者： Yu-shuang li School of Science Yanshan University Qinhuangdao 066004 China

A restricted signed r-set is a pair （A, f）, where A lohtain in [n] = {1, 2,…, n} is an r-set and f is a map from A to [n] with f（i） ≠ i for all i ∈ A. For two restricted signed sets （A, f） and （B, g）, we define an order as （A, f） ≤ （B, g） if A C B and g｜A ： f A family .A of restricted signed sets on [n] is an intersecting antiehain if for any （A, f）, （B, g） ∈ A, they are incomparable and there exists x ∈ A ∩ B such that f（x） = g（x）. In this paper, we first give a LYM-type inequality for any intersecting antichain A of restricted signed sets, from which we then obtain ｜A｜≤ （r-1^n-1）（n-1）^r-1 if A. consists of restricted signed r-sets on [n]. Unless r = n = 3, equality holds if and only if A consists of all restricted signed r-sets （A, f） such that x0∈ A and f（x0） =ε0 for some fixed x0 ∈ [n], ε0 ∈ [n] ／ {x0}.

关键词： Erdos-Ko-Rado theorem Restricted signed sets Intersecting family LYM-type inequality

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Inertial parameter estimation and control of non-cooperative target with unilateral contact constraint

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Chinese Journal of Aeronautics 2021年第3期34卷 225-240页

作者： shuang li Yuchen SHE Jun SUN College of Astronautics Nanjing University of Aeronautics and AstronauticsNanjing 210016China Shanghai Aerospace Control Technology Institute Shanghai 201109China Shanghai Key Laboratory of Aerospace Intelligent Control Technology Shanghai 201109China

In this paper, the relative sliding motion between the target and the manipulator’s endeffector is considered and characterized as a unilateral contact constraint. A new possible solution is presented to estimate the inertial parameters of a non-cooperative target while the relative sliding motion exists. First, the detailed analysis of the dynamical model is presented, and a parameterexplicit linear time-varying model is obtained. Then, an extended state observer is constructed based on the new model, which can effectively estimate the unknown inertial parameters of the target when relative sliding motion exists. As the modified reactionless controller requires the knowledge of inertial parameters, a hybrid post-capture control scheme is also established based on the switch law between different controllers. The correctness and efficiency of the proposed algorithm are validated by numerical simulation, which proves a potential framework for the non-cooperative target postcapture operation.

关键词： Non-cooperative object On-orbit servicing Post-capture control Parameter estimation Unilateral contact constraint

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Convex optimization of asteroid landing trajectories driven by solar radiation pressure

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Chinese Journal of Aeronautics 2022年第12期35卷 200-211页

作者： Chuanjun DONG Hongwei YANG shuang li Bo li College of Astronautics Nanjing University of Aeronautics and AstronauticsNanjing 211106China Tianjin Key Laboratory of Microgravity and Hypogravity Environment Simulation Technology Tianjin 300458China Tianjin Institute of Aerospace Mechanical and Electrical Equipment Tianjin 300458China

High-area/mass ratio landers driven by Solar Radiation Pressure(SRP)have potential applications for future asteroid landing *** paper develops a new convex optimization-based method for planning trajectories driven by SRP.A Minimum Landing Error(MLE)control problem is formulated to enable planning SRP-controlled trajectories with different flight *** is transformed into Second Order Cone Programming(SOCP)successfully by a series of different convexification technologies.A trust region constraint and a modified MLE objective function are used to guarantee the convergence performance of the optimization ***,the SRP-driven trajectory optimal control problem is converted equivalently into a sequence of convex optimal control problems that can be solved effectively.A set of numerical simulation results has verified the effectiveness and feasibility of the proposed optimization method.

关键词： Asteroids Convex optimization Optimal control Soft landing Solar radiation pressure Trajectory optimization

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Heteroscedastic Laplace mixture of experts regression models and applications

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Applied Mathematics(A Journal of Chinese Universities) 2021年第1期36卷 60-69页

作者： WU liu-cang ZHANG Shu-yu li shuang-shuang Faculty of Science Kunming University of Science and TechnologyKunming 650093China College of Mathematics and Informatics Fujian Normal UniversityFuzhou 350117China

Mixture of Experts(MoE)regression models are widely studied in statistics and machine learning for modeling heterogeneity in data for regression,clustering and *** distribution is one of the most important statistical tools to analyze thick and tail *** Mixture of linear Experts(LMoLE)regression models are based on the Laplace distribution which is more *** to modelling variance parameter in a homogeneous population,we propose and study a new novel class of models:heteroscedastic Laplace mixture of experts regression models to analyze the heteroscedastic data coming from a heterogeneous population in this *** issues of maximum likelihood estimation are *** particular,Minorization-Maximization(MM)algorithm for estimating the regression parameters is *** of the estimators of the regression coefficients are evaluated through Monte Carlo *** from the analysis of two real data sets are presented.

关键词： mixture of experts regression models heteroscedastic mixture of experts regression models,Laplace distribution MM algorithm

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Magnesium based degradable biomaterials： A review

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Frontiers of Materials Science 2014年第3期8卷 200-218页

作者： Xue-Nan GU shuang-shuang li Xiao-Ming li Yu-Bo FAN Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education School of Biological Science and Medical Engineering Beihang University Beijing 100191 China

Magnesium has been suggested as a revolutionary biodegradable metal for biomedical applications. The corrosion of magnesium, however, is too rapid to match the rates of tissue healing and, additionally, exhibits the localized corrosion mechanism. Thus it is necessary to control the corrosion behaviors of magnesium for their practical use. This paper comprehensively reviews the research progress on the development of representative magnesium based alloys, including Mg-Ca, Mg-Sr, Mg-Zn and Mg-REE alloy systems as well as the bulk metallic glass. The influence of alloying element on their microstructures, mechanical properties and corrosion behaviors is summarized. The mechanical and corrosion properties of wrought magnesium alloys are also discussed in comparison with those of cast alloys. Furthermore, this review also covers research carried out in the field of the degradable coatings on magnesium alloys for biomedical applications. Calcium phosphate and biodegradable polymer coatings are discussed based on different preparation techniques used. We also compare the effect of different coatings on the corrosion behaviors of magnesium alloys substrate.

关键词： magnesium alloy degradable biomaterial coating degradation corrosion

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Improved semi-analytical computation of center manifolds near collinear libration points

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Research in Astronomy and Astrophysics 2018年第11期18卷 75-88页

作者： Han-Qing Zhang shuang li College of Astronautics Nanjing University of Aeronautics and Astronautics Advanced Space Technology Laboratory Nanjing University of Aeronautics and Astronautics

In the framework of the circular restricted three-body problem, the center manifolds associated with collinear libration points contain all the bounded orbits moving around these points. Semianalytical computation of the center manifolds and the associated canonical transformation are valuable tools for exploring the design space of libration point missions. This paper deals with the refinement of reduction to the center manifold procedure. In order to reduce the amount of calculation needed and avoid repetitive computation of the Poisson bracket, a modified method is presented. By using a polynomial optimization technique, the coordinate transformation is conducted more efficiently. In addition, an alternative way to do the canonical coordinate transformation is discussed, which complements the classical approach. Numerical simulation confirms that more accurate and efficient numerical exploration of the center manifold is made possible by using the refined method.

关键词： celestial mechanics circular restricted three-body problem center manifold collinear libration point

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Interaction between plasma jet and silicone rubber covered by porous inorganic contaminants:Surface hydrophobicity or hydrophilicity?

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High Voltage 2022年第6期7卷 1023-1033页

作者： shuang li Jianjun li Yongqiang Fu Ruobing Zhang Engineering Laboratory of Power Equipment Reliability in Complicated Coastal Environments Tsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhenChina

The variation of surface hydrophobicity of silicone rubber materials covered with porous inorganic pollution layer under the action of atmospheric pressure plasma jet presents some new features,which have important engineering applications in the field of outdoor insulation of power *** of the plasma with the polluted silicone rubber is studied and surface hydrophobicity is *** results show that the exposure of plasma greatly accelerates the transfer of low molecular weight siloxanes(LMWs)in the pollution ***,the surface hydrophobicity is determined by the LMWs contents and the exposure *** acceleration effects of plasma during and after plasma exposure are proposed,their influence on surface hydrophobicity is analysed and related mechanisms are *** addition,the competing influence of plasmainduced acceleration of the transfer of LMWs towards the surface and plasmaoxidation of LMWs on surface hydrophobicity is discussed.

关键词： rubber inorganic acceleration

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QUAliTATIVE ANALYSIS OF A STOCHASTIC PREDATOR-PREY SYSTEM WITH DISEASE IN THE PREDATOR

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International Journal of Biomathematics 2013年第1期6卷 115-127页

作者： shuang li XINAN ZHANG School of Mathematics and Statistics Central China Normal University Wuhan 430079 Hubei P. R. China Department of Mathematics Xinxiang University Xinxiang 453000 Henan P. R. China School of Mathematics and Statistics Central China Normal University Wuhan 430079 Hubci P. R. China

A stochastic predator prey system with disease in the predator population is proposed, the existence of global positive solution is derived. When the white noise is small, there is a stationary distribution. In addition, conditions of global stability for the determin- istic system are also established from the above result. By Lyapunov function, the long time behavior of solution around the disease-free equilibrium of deterministic system is derived. These results mean that stochastic system has the similar property with the corresponding deterministic system. When the white noise is small, however, large envi- ronmental noise makes the result different. Finally, numerical simulations are carried out to support our findings.

关键词： Predator-prey stochastic perturbation stationary distribution stability extinct.

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