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Predictive value of serum calcium ion level in patients with colorectal cancer:A retrospective cohort study

World Journal of Gastrointestinal Surgery 2025年第3期17卷 116-130页

作者： Yin Shu Ke-Jin Li Subinur Sulayman Zi-Yi Zhang Saibihutula Ababaike Kuan Wang Xiang-yue zeng Yi Chen Ze-Liang Zhao Department of Gastrointestinal Surgery The Affiliated Cancer Hospital of Xinjiang Medical UniversityUrumqi 830000Xinjiang Uygur Autonomous RegionChina

BACKGROUND Serum calcium ion(Ca2+)is an economical and readily available indicator as a routine screening test for hospitalized *** are no studies related to serum Ca2+level and digestive tract *** To evaluate the effectiveness of serum Ca2+level in predicting the prognosis of patients with colorectal cancer(CRC).METHODS We retrospectively collected the data of 280 patients diagnosed with CRC who underwent radical surgery at the Affiliated Cancer Hospital of Xinjiang Medical *** analyzing the clinicopathological features,differences between serum Ca2+concentrations on the first day after surgery were *** used the receiver operating characteristic curve to assess the predictive ability of serum Ca2+for *** analyses were performed using the Kaplan-Meier method,and multivariate Cox proportional risk regression was used to determine association between calibration serum Ca2+levels and CRC survival *** By receiver operating characteristic curve analysis,the ideal threshold value for Ca2+the first postoperative day and delta serum calcium(δCa2+)value were 1.975 and 0.245,*** survival(OS)and progression-free survival(PFS)were better in both the high Ca2+group and highδCa2+group on the first postoperative *** variables identified through univariate analysis were incorporated into multivariate analysis and showed that tumor differ-entiation(P=0.047),T stage(P=0.019),N stage(P<0.001),nerve vascular invasion(P=0.037),carcinoembryonic antigen(P=0.039),baseline serum Ca2+level(P=0.011),and serum Ca2+level on the first day(P=0.006)were independent predictors of prognosis for patients undergoing feasible radical CRC *** the findings from the multifactorial analysis,we developed a nomogram and the calibration showed a good predictive *** Low serum Ca2+level on the first postoperative day is an independent risk factor for OS and PFS in CRC.

关键词： Serum calcium ion Colorectal cancer Prognosis Nomogram Overall survival

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圆不锈钢管超高性能混凝土短柱轴压性能研究

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工程力学 2025年第2期42卷 87-97页

作者：唐红元曾跃佳刘烨西华大学结构工程研究所成都610039 四川大学建筑与环境学院深地科学与工程教育部重点实验室成都610065

该文对6根超高性能混凝土填充不锈钢管(UHPC-filled circular stainless steel tubular,UFCSST)短柱、3根普通混凝土填充不锈钢管(Concrete-filled stainless steel tubular columns,CFSST)短柱以及3根不锈钢管进行轴压试验,试件参数包括不锈钢管壁厚和核心混凝土强度等级。观察了试件的受力破坏过程及形态,获取了荷载-位移曲线,通过试件受力过程的破坏形态、荷载-位移曲线、荷载-应变曲线、混凝土贡献率和强度提高系数对UFCSST轴压力学性能进行了分析。结果表明:UFCSST短柱失效模型与套箍系数相关,当套箍系数大于1.03时,核心混凝土由剪切型破坏向横向膨胀转变。荷载-位移曲线在峰值荷载后的变化趋势依据套箍系数大小可分为三类:一是存在下降段,后再缓慢回升至峰值荷载;二是平稳发展;三是缓慢上升。不锈钢管厚度一定时,UHPC等级对承载力影响较小,最大能提升承载力14.8%。由于UHPC强度高且内部含有钢纤维减缓UHPC内部裂缝和变形的发展,导致UHPC的混凝土贡献率比普通混凝土贡献率高81.6%,而由于UHPC自收缩性和混凝土多轴力学特性,UHPC的强度提高系数比普通混凝土低46.4%。国外部分规范计算结果较试验结果偏于保守,最大偏差可达22.4%,而国内CECS 28:2012的计算结果较试验承载力高出10.4%。基于统一强度理论提出了UFCSST承载力理论计算模型。

关键词：承载力轴压试验超高性能混凝土不锈钢管预测模型

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Machine learning models for the secondary Bjerknes force between two insonated bubbles

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Acta Mechanica Sinica 2021年第1期37卷 35-46,I0001页

作者： Haiyan Chen yue zeng Yi Li School of Material and Energy Guangdong University of TechnologyGuangzhou510006China School of Mathematics and Statistics University of SheffieldSheffieldS37RHUK

The secondary Bjerknes force plays a significant role in the evolution of bubble ***,due to the complex dependence of the force on multiple parameters,it is highly non-trivial to include its effects in the simulations of bubble *** this paper,machine learning is used to develop a data-driven model for the secondary Bjerknes force between two insonated bubbles as a function of the equilibrium radii of the bubbles,the distance between the bubbles,the amplitude and the center frequency of the ultrasound *** sign of the force may change with the phase difference between the oscillating ***,the magnitude of the force varies over several orders of magnitude,which poses a serious challenge for the usual machine learning *** overcome this difficulty,the magnitudes and the signs of the force are separated and modelled separately.A nonlinear regression is obtained with a feed-forward network model for the logarithm of the magnitude,whereas the sign is modelled by a support-vector machine *** principle,the practical aspects related to the training and validation of the machine models are *** predictions from the models are checked against the values computed from the Keller-Miksis *** results show that the models are extremely efficient while providing accurate estimate of the *** models make it computationally feasible for the future simulations of the bubble clusters to include the effects of the secondary Bjerknes force.

关键词： Bubble clusters Secondary Bjerknes force Machine learning Neural networks Support-vector machine Numerical simulations

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Bifurcation and Stability Analysis of the Hamiltonian-Casimir Model of Liquid Sloshing

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Chinese Physics Letters 2012年第6期29卷 46-49页

作者： Salman Ahmad yue Bao-zeng Department of Humanities&Sciences Institute of Space TechnologyIslamabad 44000Pakistan Department of Mechanics School of Aerospace EngineeringBeijing Institute of TechnologyBeijing 100081

Motion stability of a spacecraft is discussed.A canonical Hamiltonian model for liquid sloshing is presented for a moving rigid *** equivalent mechanical pendulum model is used to represent the fuel slosh inside the *** this model sloshing is represented by the moving mass,the rest of the mass of the spacecraft is assumed to be *** spacecraft structure is considered to be an elliptical rigid shape and the steady rotation along the x-axis is taken as the major-axis *** stability for the present model is analyzed using the Lyapunov theory with Casimir energy *** for stability and instability are derived for a steady principal axis rotation of the rigid *** results are presented to distribute the region into stable and unstable *** this,the nonlinear behavior of the system is analyzed under the influence of an external force acting *** is observed through a bifurcation *** time history map and phase portrait are also presented to analyze the nonlinear behavior of the system.

关键词： Hamiltonian rotation stability

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Coupling dynamic analysis of spacecraft with multiple cylindrical tanks and flexible appendages

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Acta Mechanica Sinica 2016年第1期32卷 144-155页

作者： Wen-Jun Wu Bao-zeng yue Hua Huang School of Aerospace Engineering Beijing Institute of Technology School of Automobile and Traffic Engineering Guangxi University of Science and Technology Satellite Communication Department China Academy of Space Technology

This paper is mainly concerned with the coupling dynamic analysis of a complex spacecraft consisting of one main rigid platform, multiple liquid-filled cylindrical tanks, and a number of flexible appendages. Firstly, the carrier potential function equations of liquid in the tanks are deduced according to the wall boundary conditions. Through employ- ing the Fourier-Bessel series expansion method, the dynamic boundaries conditions on a curved free-surface under a low-gravity environment are transformed to general simple differential equations and the rigid-liquid coupled sloshing dynamic state equations of liquid in tanks are obtained. The state vectors of rigid-liquid coupled equations are composed with the modal coordinates of the relative potential func- tion and the modal coordinates of wave height. Based on the B ernoulli-Euler beam theory and the D＇Alembert＇s prin- ciple, the rigid-flexible coupled dynamic state equations of flexible appendages are directly derived, and the coordi- nate transform matrixes of maneuvering flexible appendages are precisely computed as time-varying. Then, the cou- pling dynamics state equations of the overall system of the spacecraft are modularly built by means of the Lagrange＇s equations in terms of quasi-coordinates. Lastly, the cou-piing dynamic performances of a typical complex spacecraft are studied. The availability and reliability of the presented method are also confirmed.

关键词： Multiple liquid-filled cylindrical tanks TheFourier-Bessel series expansion method Low-gravityenvironment Maneuvering flexible appendages TheLagrange's equations in terms of quasi-coordinates

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On Chaotification of Discrete Lagrange Systems

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Communications in Theoretical Physics 2006年第5期45卷 861-863页

作者： LI Guang-Cheng yue Bao-zeng Department of Mechanics Beijing Institute of Technology Beijing 100081 China

This paper is concerned with chaotification of discrete Lagrange systems in one dimension, via feedback control techniques. A chaotification theorem for discrete Lagrange systems is established. The controlled systems are proved to be chaotic in the sense of Devaney. In particular, the systems corresponding to the original systems and designed controllers are only required to satisfy, some mild assumptions.

关键词： discrete Lagrange systems chaotification anti-integrable limit

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Investigation on attitude disturbance control and vibration suppression for fuel-fille flexibl spacecraft

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Acta Mechanica Sinica 2015年第4期31卷 581-588页

作者： Xiao-Juan Song Bao-zeng yue Wen-Jun Wu School of Aerospace Engineering Beijing Institute of Technology School of Automobile and Traffi Engineering Guangxi University of Science and Technology

This paper is mainly focused on the attitude dynamics and control of a fuel-filled flexible spacecraft sub- jected to the thermal payload during eclipse transitions. The flexible appendages are considered as Euler-Bernoulli beams, and the sloshing liquid is modeled as in two modes multi-spring-mass models; the governing equations of this coupled system are developed by using Hamilton＇s prin- ciple. Numerical results show that the spacecraft attitude responses consist of a quasi-static displacement and superim- posed vibration. Then, we design an adaptive sliding mode and use the Lyapunov approach control law to control the attitude disturbance and suppress the thermal jitter and liq- uid sloshing for the fuel filled flexible spacecraft subject to the thermal payload. Numerical results are presented to verify the efficiency of the hybrid control methods. The results show that the adaptive sliding mode method might be effective to handle the steady-state errors and the Lyapunov control algo- rithm would suppress the residual vibration.

关键词： Fuel-filled flexible spacecraft Thermalpayload Adaptive sliding mode Lyapunov approachcontrol law

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Nonlinear Dynamics in a New Double Chain-Model of DNA

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Communications in Theoretical Physics 2001年第12期36卷 737-742页

作者： KONG De-Xing LOU Sen-yue zeng Jin Department of Applied Mathematics Shanghai Jiao Tong University Shanghai 200030 China Department of PhysicsShanghai Jiao Tong UniversityShanghai 200030China Department of Applied Mathematics Shanghai Jiao Tong University Shanghai 200030 China

We investigate the mechanics ofa new double chain-model of DNA. The model consists of two long elastic homogeneous strands (or rods), which represent two polynucleotide chains of the DNA molecule, connected with each other by an elastic membrane (or some linear springs) representing the hydrogen bonds between the base pairs of the two chains. The nonlinear dynamical equations are derived and some solitary wave solutions are discussed. By the way,our model can be regarded as the mechanical model of cubic nonlinear Klein-Gordon equation and 4-field equation.

关键词： double chain-model of DNA, nonlinear dynamics, solitary wave solutions

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低氧胁迫对虹鳟心脏生化指标和低氧相关基因表达的影响

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渔业科学进展 2025年第1期46卷 82-92页

作者：马九菊黄进强李永娟吴深基赵璐曾粤甘肃农业大学动物科学技术学院甘肃兰州730070

虹鳟(Oncorhynchus mykiss)是一种低氧敏感性鱼类,低氧胁迫下其生长、行为、代谢和免疫等均会受到影响。为了解低氧胁迫对虹鳟心脏生化指标和低氧相关基因表达的影响,本研究用酶活性测定和实时荧光定量PCR(RT-qPCR)方法,分析中度低氧[(... 详细信息

虹鳟(Oncorhynchus mykiss)是一种低氧敏感性鱼类,低氧胁迫下其生长、行为、代谢和免疫等均会受到影响。为了解低氧胁迫对虹鳟心脏生化指标和低氧相关基因表达的影响,本研究用酶活性测定和实时荧光定量PCR(RT-qPCR)方法,分析中度低氧[(4.5±0.1)mg/L]和重度低氧[(3.0±0.1)mg/L]胁迫4、8、12、24 h、中度低氧1个月(TMM)、重度低氧1个月(TMS)及复氧[(8.5±0.1)mg/L]12 h和24 h后虹鳟心脏中生化指标变化以及低氧相关基因的表达情况。结果显示,在中度低氧胁迫下,虹鳟心脏中丙酮酸激酶(PK)、总胆固醇(TC)、乳酸(LD)和谷丙转氨酶(GPT)水平在8 h时升高,24 h时降低,复氧后仍显著高于对照水平(P0.05)。三磷酸腺苷酶(ATPase)、脂肪酶(LPS)、TC、谷草转氨酶(GOT)和GPT水平在12 h时降低,复氧后均恢复至正常水平(P>0.05)。与对照组相比,TMM组和TMS组中PK、TC、乳酸脱氢酶(LDH)和GPT水平均显著升高(P0.05),重度低氧胁迫下pk、sdh和vhl基因表达量显著升高(P<0.05)。本研究结果表明,低氧胁迫使虹鳟心脏发生代谢紊乱,影响体内正常的代谢水平,并对虹鳟心脏造成一定损伤。本研究可为进一步阐明虹鳟低氧胁迫的调控机制提供基础资料。

关键词：虹鳟低氧胁迫生化指标代谢基因表达

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A Comparison of Shale Gas Fracturing Based on Deep and Shallow Shale Reservoirs in the United States and China

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Computer Modeling in Engineering & Sciences 2022年第12期133卷 471-507页

作者： Qixing Zhang Bing Hou Huiwen Pang Shan Liu yue zeng State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing102249China Key Laboratory of Petroleum Engineering Ministry of EducationChina University of Petroleum(Beijing)Beijing102249China

China began to build its national shale gas demonstration area in *** central exploration,drilling,and development technologies for medium and shallow marine shale reservoirs with less than 3,500m of buried depth in Changning-Weiyuan,Zhaotong,and other regions had *** this study,we macroscopically investigated the development history of shale gas in the United States and China and compared the physical and mechanical conditions of deep and shallow *** comparative results revealed that themain reasons for the order-ofmagnitude difference between China’s annual shale gas output and the United States could be attributed to three aspects:reservoir buried depth,reservoir physical and mechanical properties,and engineering technology *** current engineering technology level of China could not meet the requirements of increasing production and reducing costs for deep shale gas reservoirs;they had reached the beneficial threshold development stage and lacked the capacity for large-scale commercial *** identified several physical and mechanical reasons for this threshold development *** shale reservoirs were affected by the bedding fracture,low brittleness index,low clay mineral content,and significant areal differences,as well as by the transformation from elasticity to plasticity,difficulty in sanding,and high mechanical and strength ***,they were accompanied by six high values of formation temperature,horizontal principal stress difference,pore pressure,fracture pressure,extension pressure,and closure *** key to deep shale gas horizontal well fracturing was to improve the complexity of the hydraulic fracture network,formadequate proppant support of fracture surface,and increase the practical stimulated reservoir volume(SRV),which accompanied visual hydraulic discrete network *** this basis,we proposed several ideas to improve China’s deep shale gas development involving advanced technolo

关键词： Deep and shallow shale in the United States and China physical and mechanical properties multistage/multicluster fractures network monitoring soak well and flow back

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