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Combined treatment of oxaliplatin and capecitabine in patients with metastatic esophageal squamous cell cancer

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World Journal of Gastroenterology 2009年第7期15卷 871-876页

作者： Tian-Jie Qin Gai-Li An xin-Han Zhao Fang Tian xiao-Hua Li Juan-Wen Lian Bo-Rong Pan Shan-Zhi Gu Department of Medical Oncology First Affiliated Hospital of Medical School of Xi'an Jiaotong University Xi'an 710061 Shaanxi Province China Department of Oncology Cancer Institute Fourth Military Medical University Xi'an 710032 Shaanxi Province China Key Laboratory of Environment and Genes Related to Diseases Ministry of Education School of Medicine of xi'an Jiaotong university Xi'an 710061 Shaanxi Province China

AIM:To investigate the efficacy and side effects of the combined therapy of oxaliplatin and capecitabine in patients with metastatic esophageal squamous cell cancer(ESCC) and the survival of the ***:Sixty-four patients(median age of 63 years) with histological or cytological confirmation of ESCC received oxaliplatin 120 mg/m2 intravenously on day 1 and capecitabine 1000 mg/m2 orally twice daily on days 1 to 14 in a 21-d treatment cycle as palliative *** patient received at least two cycles of *** efficacy,side effects and patient survival were ***:The partial response(PR) rate was 43.8%(28/64).Stable disease(SD) rate was 47.9%(26/64),and disease progression rate was 15.6%(10/64).The clinical benefit rate(PR + SD) was 84.4%.The main toxicities were leukopenia(50.0%),nausea and vomiting(51.6%),diarrhea(50.0%),stomatitis(39.1%),polyneuropathy(37.5%) and hand-foot syndrome(37.5%).No grade 4 event in the entire cohort was *** median progression-free survival was 4 mo,median overall survival was 10 mo(95% CI:8.3-11.7 mo),and the 1-and 2-year survival rates were 38.1% and 8.2%,*** Karnofsky index,single metastatic lesion and response to the regimen indicated respectively good ***:Oxaliplatin plus capecitabine regimen is effective and tolerable in metastatic ESCC *** regimen has improved the survival moderately and merits further studies.

关键词： Oxaliplatin Capecitabine Metastaticesophageal squamous cell cancer Survival analysis

Distribution,risk evaluation,and source analysis of the heavy metals in the sediment deposition of the lower Shichuanhe River,Shaanxi,China

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地球化学学报(英文) 2023年第5期42卷 832-844页

作者： Chenhui Hou Caixia Feng Shen Liu Department of Geology Northwest UniversityXi’an 710069China

In this study, 30 sediment samples were collected from the lower reaches of the Shichuanhe River in xi’an, Shaanxi Province, China, to test the distribution of heavy metal elements in this area and for an analysis of the pollution levels of this area, hope to provide guidance on agricultural production activities in this region. The results show that the heavy metal elements in this area are mainly concentrated at the Qinghe River and Shichuanhe River confluences. Furthermore, the element contents are higher than that of the background levels of the continental crust(UCC) and close to the background levels of the soil from Shaanxi Province;the two most enriched elements are Cd and As, with contents of 0.79 and 22.7 mg·kg-1, respectively, and their contents are 3.8 and 1.72 times higher than that of the background values. Herein, the heavy metal pollution assessment methods applied indicated that Cd and As are the two most abundant pollutant elements in the area’s soils. As has a peak geo-accumulation index value of 3, and the pollution level is high, while Cd exhibits high potential ecological risks due to its high toxicity(potential risk index of 143) and an active fraction of more than 64%.In addition, a principal component analysis and hierarchical cluster analysis study showed that there are two sources of the heavy metals in this area. The Zn, As, Ni, Cu, Pb,and Cr are mainly from natural sources, and the Cd likely comes from a discharge of untreated agricultural wastewater in the region. The Cd which poses a high potential risk and mainly results from human activities, needs to be further monitored.

关键词： Distribution Risk evaluation Source analysis Heavy metals Sediment Ecological risk

Supercritical Characteristics of a Relaxation Oscillator

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Chinese Physics Letters 1991年第1期8卷 1-4页

作者： JI Feng LIU Hui YANG Zhenghai SHI Kangjie HE Daren WANG Dalcai Department of Physics Northwestern UniversityXi’an 710069

A relaxation oscillator can be described by two maps:one circle and one inverse *** order of map depends on the function form of the modulation *** behaviors of the oscillator were studied experimentally and *** scaling laws S(f)∝f^(-δ) and τ∝|f-f_(c)|^(-γ) were *** the scaling exponents δ and γ2 increase when the order m getting larger.

关键词： oscillator scaling Oscillator

Influence of Strut Cross-section of Stents on Local Hemodynamics in Stented Arteries

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Chinese Journal of Mechanical Engineering 2016年第3期29卷 624-632页

作者： JIANG Yongfei ZHANG Jun ZHAO Wanhua State Key Laboratory for Manufacturing System Engineering Xi'an Jiaotong University

Stenting is a very effective treatment for stenotic vascular diseases, but vascular geometries altered by stent implantation may lead to flow disturbances which play an important role in the initiation and progression of restenosis, especially in the near wall in stented arterial regions. So stent designs have become one of the indispensable factors needed to be considered for reducing the flow disturbances. In this paper, the structural designs of strut cross-section are considered as an aspect of stent designs to be studied in details. Six virtual stents with different strut cross-section are designed for deployments in the same ideal arterial model. Computational fluid dynamics（CFD） methods are performed to study how the shape and the aspect ratio（AR） of strut cross-section modified the local hemodynamics in the stented segments. The results indicate that stents with different strut cross-sections have different influence on the hemodynamics. Stents with streamlined cross-sectional struts for circular arc or elliptical arc can significantly enhance wall shear stress（WSS） in the stented segments, and reduce the flow disturbances around stent struts. The performances of stents with streamlined cross-sectional struts are better than that of stents with non-streamlined cross-sectional struts for rectangle. The results also show that stents with a larger AR cross-section are more conductive to improve the blood flow. The present study provides an understanding of the flow physics in the vicinity of stent struts and indicates that the shape and AR of strut cross-section ought to be considered as important factors to minimize flow disturbance in stent designs.

关键词： stent restenosis wall shear stress hemodynamics computational fluid dynamics

Undrained semi-analytical solution for cylindrical cavity expansion in anisotropic soils under biaxial stress conditions

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第5期15卷 1284-1297页

作者： Lele Hou xiaolin Weng Jibo Hu Rongming Zhou School of Highway Chang’an UniversityXi’an710064China

This paper presents an undrained semi-analytical elastoplastic solution for cylindrical cavity expansion in anisotropic soil under the biaxial stress *** advanced simplified SANICLAY model is used to simulate the elastoplastic behavior of *** cavity expansion is treated as an initial value problem and solved as a system of eight first-order ordinary differential equations including four stress components and four anisotropic *** results are validated by comparing the new solutions with existing *** distributions of stress components and anisotropic parameters around the cavity wall,the expansion process,the stress yield trajectory of a soil element and the shape and size of elastoplastic boundary are further investigated to explore the cavity expansion response of soils under biaxial in situ *** results of extensive parameters analysis demonstrate that the circumferential position of the soil element and the anisotropy of the soils have noticeable impacts on the expansion response under biaxial in situ *** the present solution not only considers the anisotropy and anisotropy evolution of natural soil,but also eliminates the conventional assumption of uniform radial pressure,the solution is better than other theoretical solutions to explain the pressure test and pile installation effect of shallow saturated soil.

关键词： Cylindrical cavity expansion Anisotropic soil Undrained solution Biaxial in situ stresses

3D Trajectory Planning of Positioning Error Correction Based on PSO-A* Algorithm

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Computers, Materials & Continua 2020年第12期65卷 2295-2308页

作者： Huaixi xing Yu Zhao Yuhui Zhang You Chen Air Force Engineering university Xi’an710038China

Aiming at the yaw problem caused by inertial navigation system errors accumulation during the navigation of an intelligent aircraft,a three-dimensional trajectory planning method based on the particle swarm optimization-A star(PSO-A*)algorithm is ***,an environment model for aircraft error correction is established,and the trajectory is discretized to calculate the positioning ***,the positioning error is corrected at many preset trajectory *** shortest trajectory and the fewest correction times are regarded as optimization goals to improve the heuristic function of A star(A*)***,the index weights are continuously optimized by the particle swarm optimization *** optimal trajectory is found by the A*algorithm under the current evaluation index,so the ideal trajectory is *** experimental results show that the PSO-A*algorithm can quickly search for ideal trajectories in different environment models,indicating that the algorithm has certain feasibility and adaptability,and verifies the rationality of the proposed trajectory planning *** PSO-A*algorithm has better convergence accuracy than the A*algorithm,and the search efficiency is significantly better than the grid search A star(GS-A*)*** PSO-A*algorithm proposed in this paper has certain engineering application *** researchers will study the real-time and systematic nature of the algorithm.

关键词： Trajectory planning PSO-A* error correction intelligent aircraft

Growth of Casting Microcrack and Micropore in Single-crystal Superalloys Analysed by Three-Dimensional Unit Cell

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Journal of Materials Science & Technology 2006年第2期22卷 183-189页

作者： Jiansong WAN Zhenzhou LU Zhufeng YUE Department of Engineering Mechanics Northwestern Polytechnical University Xi＇an 710072 China

Finite element （FE） analysis was employed to investigate the casting microcrack and micropore growth in nickel-base single-crystal superalloys DD3. Based on the finite deformation rate-dependent crystallographic constitutive equation, the simulations of casting microcrack and micropore growth in three-dimensional unit cell model were carried out in a range of parameters including stress triaxiality, Lode parameter and type of activated slip systems. The FE results show that the stress triaxiality has profound effects on growth behavior, and the Lode parameter is also important for the casting microcrack and micropore growth. The type of operative slip systems has remarkable effect on casting microcrack and micropore growth, so the life of single- crystal component is associated with the type of activated slip systems, which is related to Schmid factor and the number of activated slip systems. The growth comparison between microcrack and micropore reveals that when the material is subjected to large deformation, the growth rate of microcrack is faster than that of micropore, i.e. microcrack is more dangerous than micropore; the microcrack is easier to result in brittle fracture than micropore. The stress triaxiality and Lode parameter have strong influence on the growth of microcrack and micropore.

关键词： Casting micropore Casting crack Single-crystal superalloys Crystallographic constitutive equation

Nonlinear dynamics of self-oscillating polymer gels

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Science China(Technological Sciences) 2010年第7期53卷 1862-1868页

作者： WANG PengFei1, ZHOU Jinxiong1, LI MeiE2, XU Feng1,3 & LU TianJian1 1 Biomedical Engineering and Biomechanics Center, SV Laboratory, xi’an Jiaotong university, xi’an 710049, China 2 School of Materials Science and Engineering, xi’an Jiaotong university, xi’an 710049, China 3 HST Center for Biomedical Engineering, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, 510660, USA Biomedical Engineering and Biomechanics Center SV Laboratory Xi’an Jiaotong University Xi’an China School of Materials Science and Engineering Xi’an Jiaotong University Xi’an China HST Center for Biomedical Engineering Department of Medicine Brigham and Women’s Hospital Harvard Medical School Boston USA

Self-oscillating polymer gels driven by Belousov-Zhabotinsky (BZ) chemical reaction are a new class of functional gels that have a wide range of potential applications (e.g., autonomously functioning membranes, actuate artificial muscles). However, the precise control of these gels has been an issue due to limited investigations of the influences of key system parameters on the characteristics of BZ gels. To address this deficiency, we studied the self-oscillating behavior of BZ gels using the nonline-ar dynamics theory and an Oregonator-like model, with focus placed upon the influences of various system parameters. The analysis of the oscillation phase indicated that the dynamic response of BZ gels represents the classical limit cycle oscillation. We then investigated the characteristics of the limit cycle oscillation and quantified the influences of key parameters (i.e., ini-tial reactant concentration, oxidation and reduction rate of catalyst, and response coefficient) on the self-oscillating behavior of BZ gels. The results demonstrated that sustained limit cycle oscillation of BZ gels can be achieved only when these key pa-rameters meet certain requirements, and that the pattern, period and amplitude of the oscillation are significantly influenced by these parameters. The results obtained in this study could enable the controlled self-oscillation of BZ gels system. This has several potential applications such as controlled drug delivery, miniature peristaltic pumps and microactuators.

关键词： Belousov-Zhabotinsky reaction self-oscillating gels numerical simulation limit cycle parameter analysis

Morphology-controlled growth of large-area PtSe_(2) films for enhanced hydrogen evolution reaction

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Rare Metals 2022年第4期41卷 1314-1322页

作者： Rui Hao Qing-Liang Feng xiao-Jian Wang Yi-Chen Zhang Kan-She Li College of Chemistry and Chemical Engineering Polymer Research InstituteXi’an University of Science and TechnologyXi’an 710054China Key Laboratory of Special Functional and Smart Polymer Materials of MIIT School of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’an 710072China

Transition metal dichalcogenides(TMDs)have emerged as a promising electrocatalyst for hydrogen evo-lution reaction(HER)due to its excellent conductivity and abundant electrocatalytic active sites of its *** nanowall can expose abundant of edges so that they tend to show better catalytic performance for hydrogen evolution ***,PtSe_(2) nanowall films with morphology controlled at centimeters level are synthesized by selenizing Pt *** dynamic and thermodynamics of selenation reaction are *** nanowall structure can be obtained by controlling the growth temperature,and the thickness of nanowall can be tuned by the original thickness of Pt *** Pt atoms can be rearranged into ordered distribution at 550℃ and can be induced to well-ordered PtSe_(2) nanowalls *** well-ordered PtSe_(2) nanowall films show excellent HER performance,with an overpotential of 0.3 V at-10 mA·cm^(-2) and a Tafel slope of~52 mV·dec^(-1).This work demonstrates the great potential of activated 2D PtSe_(2) as an ultrathin film catalyst for the HER,which is valuable to provide instruction and afford experience for further application at industrial level.

关键词： Large area PtSe2 Nanowall Morphology controlled HER