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Breakdown of Scaling in Aggregation-Fragmentation- Annihilation Process of n-Species Systems

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Communications in Theoretical Physics 2002年第8期38卷 235-242页

作者： ke jian-Hong LIN Zhen-Quan Department of Physics and Electronic Information Science Wenzhou Normal College Wenzhou 325027 China Department of Physics and Electronic Information Science Wenzhou Normal College Wenzhou 325027 China

The kinetic behaviors of aggregation-fragmentation-annihilation processes of three n-species systems arestudied in this paper. Aggregation reaction occurs only between the same species but irreversible annihilation reactionoccurs between two different species, and meanwhile the fragmentation reaction coexists. Based on the mean-field theory,we investigate the rate equations of the processes and obtain the asymptotic descriptions of the cluster-mass distributionsfor the symmetrical cases. We find that the fragmentation reaction may lead to the complete breakdown of the standardscaling description for the cluster-mass distribution of each species contrast to the scaling behavior of aggregation-annihilation processes without *** our joint annihilation model, we also observe that the kinetic behaviorsof distinct species are quite complicated for the case with different initial concentrations. The cluster-mass distributionof heavy species with the largest initial concentration possesses peculiar scaling properties, while that of light species hasnot scaling behavior.

关键词： kinetic behavior, aggregation-fragmentation-annihilation process, scaling law, rate equation

A pilot study on combination of cryosurgery and ^(125)iodine seed implantation for treatment of locally advanced pancreatic cancer

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World Journal of Gastroenterology 2008年第10期14卷 1603-1611页

作者： ke-Cheng Xu Li-Zhi Niu Yi-Ze Hu Wei-Bing he Yi-Song he Ying-Fei Li jian-Sheng Zuo Cryosurgery Center for Cancer Fuda Cancer Hospital Guangzhou Guangzhou 510300 Guangdong ProvinceChina Department of hepato-biliary Surgery Second affiliated Hospital Guangzhou Medical College Guangzhou 510260 Guangdong Province China Department of Gastroenterology Nanfang Hospital Nanfang Medical university Guangzhou 510515 Guangdong Province China

AIM: To study the therapeutic value of combination o cryosurgery and 125iodine seed implantation for locally advanced pancreatic cancer. METHODS: Forty-nine patients with locally advanced pancreatic cancer (males 36, females 13), with a median age of 59 years, were enrolled in the study. Twelve patients had liver metastases. In all cases the tumors were considered unresectable after a comprehensive evaluation. Patients were treated with cryosurgery, which was performed intraoperatively or percutaneously unde guidance of ultrasound and/or computed tomography (CT), and 125iodine seed implantation, which was performed during cryosurgery or post-cryosurgery under guidance of ultrasound and/or CT. A few patients received regional celiac artery chemotherapy. RESULTS: Thirteen patients received intraoperative cryosurgery and 36 received percutaneous cryosurgery Some patients underwent repeat cryosurgery. 125Iodine seed implantation was performed during freezing procedure in 35 patients and 3-9 d after cryosurgery in 14 cases. Twenty patients, 10 of whom had hepaticmetastases received regional chemotherapy. At 3 mo after therapy, CT was repeated to estimate tumor response to therapy. Most patients showed varying degrees of tumor necrosis. Complete response (CR) of tumor was seen in 20.4% patients, partial response (PR), in 38.8%, stable disease (SD), in 30.6%, and progressive disease (PD), in 10.2%. Adverse effects associated with cryosurgery included upper abdomen pain and increased serum amylase. Acute pancreatitis was seen in 6 patients one of whom developed severe pancreatitis. All adverse effects were controlled by medical management with no poor outcome. There was no therapy-related mortality. During a median follow-up of 18 mo (range of 5-40), the median survival was 16.2 mo, with 26 patients (53.1%) surviving for 12 mo or more. Overall, the 6-, 12-, 24- and 36-mo survival rates were 94.9%, 63.1%, 22.8% and 9.5%, respectively. Eight patients had survival of 24 mo or

关键词： Pancreatic cancer Cryosurgery Cryoablation ^125Iodine seed implantation

A New Ductile Fracture Criterion for Various Deformation Conditions Based on Microvoid Model

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Journal of Iron and Steel Research International 2009年第5期16卷 92-97,86页

作者： HUANG jian-ke DONG Xiang-huai National Die and Mould CAD Engineering Research Center Shanghai Jiao Tong University Shanghai 200030 China

To accurately predict the occurrence of ductile fracture in metal forming processes, the Gurson-Tvergaard （GT） porous material model with optimized adjustment parameters is adopted to analyze the macroscopic stressstrain response, and a practical void nucleation law is proposed with a few material constants for engineering applications. Mechanical and metallographic analyses of uniaxial tension, torsion and upsetting experiments are performed. According to the character of the metal forming processes, the basic mechanisms of ductile fracture are divided into two modes： tension-type mode and shear-type mode. A unified fracture criterion is proposed for wide applicable range, and the comparison of experimental results with numerical analysis results confirms the validity of the newly proposed ductile fracture criterion based on the GT porous material model.

关键词： ductile fracture metal forming process void nucleation mechanical analysis metallographic analysis

Diagnosis and treatment of an elderly patient with 2019-nCoV pneumonia and acute exacerbation of chronic obstructive pulmonary disease in Gansu Province:A case report

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World Journal of Clinical Cases 2020年第17期8卷 3903-3910页

作者： Tian-Peng he Dong-Liang Wang Jing Zhao Xiao-Ying jiang Jin he jian-ke Feng Yuan Yuan First Department of Critical Care Medicine Gansu Provincial HospitalLanzhou 730000Gansu ProvinceChina Department of Medical Gansu Provincial HospitalLanzhou 730000Gansu ProvinceChina Department of Medical Infectious Diseases of Gansu Provincial HospitalTianshui 741024Gansu ProvinceChina

BACKGROUND In December 2019,the first patient with 2019-novel coronavirus(2019-nCoV)was reported in Wuhan,China,and the disease spread rapidly across the country and surrounding countries within 2 *** of February 29,2020,a total of 91 confirmed cases had been reported in Gansu *** case report of the diagnosis and treatment of an elderly patient with 2019-nCoV pneumonia complicated by acute exacerbation of chronic obstructive pulmonary disease in Gansu Province aims to provide a better reference for the treatment of patients in the *** SUMMARY The patient,a 94-year-old female,lived in Maiji District of Tianshui,Gansu Province,*** January 30,2020,she was admitted to the Fourth People’s Hospital of Tianshui after 9 d of close contact with a patient with 2019-nCoV *** was subsequently admitted to Gansu Provincial Hospital of Traditional Chinese Medicine for isolation and transferred to Tianshui Gansu Provincial Hospital of Infectious Diseases on February 3,2020 for *** initial examination,her body temperature was 36.7°C,pulse was 80,breathing was 20,and blood pressure was 130/80 *** was conscious with normal development and normal *** pharynx was not red,and bilateral tonsils were not red and *** lungs sounded slightly coarse with no dry or wet *** first symptoms were cough and fatigue on 2 *** patient was hospitalized for 12 *** active treatment,she was discharged on February 14 with a good *** A history of exposure to the affected area or patient is a major cause of 2019-nCoV infection,and population clustering is a high risk factor for *** may not necessarily have respiratory system symptoms as the only clinical manifestation but may also have concomitant or first onset digestive *** should be paid to the prevention and treatment of multiple organ dysfunction *** acid testing is extremely important and needs to be repe

关键词： 2019-nCoV pneumonia Acute exacerbation of chronic obstructive pulmonary disease Epidemiological investigation Clinical manifestations Integrated Chinese and Western medicine treatment

SOLUTION OF 2D SHALLOW WATER EQUATIONS BY GENUINELY MULTIDIMENSIONAL SEMI-DISCRETE CENTRAL SCheME

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Journal of Hydrodynamics 2006年第4期18卷 436-442页

作者： CheN jian-zhong, SHI Zhong-ke College of Automation Northwestern Polytechnical University Xi＇an 710072 China

A numerical two-dimensional shallow water method was based on method for solving the equations was presented. This the third-order genuinely multidimensional semi-discrete central scheme for spatial discretization and the optimal third-order Strong Stability Preserving （SSP） Runge-Kutta method for time integration. The third-order compact Central Weighted Essentially Non-Oscillatory （CWENO） reconstruction was adopted to guarantee the non-oscillatory behavior of the presented scheme and improve the resolution. Two kinds of source terms were considered in this work. They were evaluated using different approaches. The resulting scheme does not require Riemann solvers or characteristic decomposition, hence it retains all the attractive features of central schemes such as simplicity and high resolution. To evaluate the performance of the presented scheme, several numerical examples were tested. The results demonstrate that our method is efficient, stable and robust.

关键词： 2D shallow water equations semi-discrete central scheme Central Weighted Essentially Non-Oscil]atory (CWENO) reconstruction

Time-domain solution for transient dynamic response of a large-diameter thin-walled pipe pile

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Earthquake Engineering and Engineering Vibration 2015年第2期14卷 239-251页

作者： Ding Xuanming Liu Hanlong Chu jian Cheng ke key Laboratory of New Technology for Construction of Cities in Mountain Area (Chongqing University) Ministry of Education Department of Civil Construction & Environmental Engineering Iowa State University 328 Town Engineering Building School of Mechanical and Power Engineering Nanjing University of Technology

The propagation of stress waves in a large-diameter pipe pile for low strain dynamic testing cannot be explained properly by traditional 1D wave theories. A new computational model is established to obtain a wave equation that can describe the dynamic response of a large-diameter thin-walled pipe pile to a transient point load during a low strain integrity test. An analytical solution in the time domain is deduced using the separation of variables and variation of constant methods. The validity of this new solution is verifi ed by an existing analytical solution under free boundary conditions. The results of this time domain solution are also compared with the results of a frequency domain solution and fi eld test data. The comparisons indicate that the new solution agrees well with the results of previous solutions. Parametric studies using the new solution with reference to a case study are also carried out. The results show that the mode number affects the accuracy of the dynamic response. A mode number greater than 10 is required to enable the calculated dynamic responses to be independent of the mode number. The dynamic response is also greatly affected by soil properties. The larger the side resistance, the smaller the displacement response and the smaller the refl ected velocity wave crest. The displacement increases as the stress waves propagate along the pile when the pile shaft is free. The incident waves of displacement and velocity responses of the pile are not the same among different points in the circumferential direction on the pile top. However, the arrival time and peak value of the pile tip refl ected waves are almost the same among different points on the pile top.

关键词： pipe pile transient load analytical solution time

Differences in brain-derived neurotrophic factor gene polymorphisms between acute ischemic stroke patients and healthy controls in the Han population of southwest China

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Neural Regeneration Research 2019年第8期14卷 1404-1411页

作者： Jie Zhou Meng-Meng Ma Jing-Huan Fang Lei Zhao Mu-ke Zhou jian Guo Li he Department of Neurology West China Hospital Sichuan University

Single-nucleotide polymorphisms in the brain-derived neurotrophic factor gene may affect the secretion and function of brain-derived neurotrophic factor, thereby affecting the occurrence, severity and prognosis of ischemic stroke. This case-control study included 778 patients (475 males and 303 females, mean age of 64.0 ± 12.6 years) in the acute phase of ischemic stroke and 865 control subjects (438 males and 427 females, mean age of 51.7 ± 14.7 years) from the Department of Neurology, Wes: China Hospital, Sichuan University, China between September 2011 and December 2014. The patients' severities of neurological defici:s in the acute phase were assessed using the National Institutes of health Stroke Scale immediately after admission to hospital. The ischemic stroke patients were divided into different subtypes according to the Trial of Org 10172 in Acute Stroke Treatment classification. Early prognosis was evaluated using the Modified Rankin Scale when the patients were discharged. Genomic DNA was extracted from peripheral blood of participants. Genotyping of rs7124442 and rs6265 was performed using Kompetitive Allele Specific polymerase chain reaction genotyping technology. Our results demonstrated that patients who carried the C allele of the rs7124442 locus had a lower risk of poor prognosis than the T allele carriers (odds ratio [OR]= 0.67;95% confidence interval [CI]: 0.45-1.00;P = 0.048). The patients with the CC or TC genotype also exhibited lower risk than TT carriers (OR = 0.65;95% CI: 0.42-1.00;P = 0.049). The AA genotype at the rs6265 locus was associated with the occurrence of ischemic stroke in patients with large-artery atherosclerosis (OR = 0.5& 95% CI: 0.37-0.90;P = 0.015). We found that the C allele (CC and TC genotypes) at the rs7124442 locus may be protective for the prognosis of ischemic stroke. The AA genotype at the rs6265 locus is likely a protective factor against the occurrence of ischemic stroke in patients with large-artery atheroscleros

关键词： nerve regeneration ischemic stroke brain-derived neurotrophic factor single-nucleotide polymorphism risk stroke severity prognosis rs6265 rs7124442 neural regeneration

Friction factor and heat transfer of nanofluid in the turbulent flow through a 90°bend

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Journal of Hydrodynamics 2021年第6期33卷 1105-1118页

作者： Pei-jie Zhang jian-zhong Lin Xiao-ke Ku Department of Mechanics State Key Laboratory of Fluid Power and Mechatronic SystemZhejiang UniversityHangzhou 310027China

heat transfer and energy performance of Al_(2)O_(3)/water nanofluid in a 90°bend with circular cross-section are investigated in the range of Reynolds number(Re)from 5000 to 30000,particle volume concentration(Φ)from 0.005%to 4%,Schmidt number(Sc)from 9870 to 296100,Dean number(De)from 6636 to *** momentum and energy equations of nanofluid together with the dynamic equation for nanoparticles are solved numerically with the particle convection,diffusion,coagulation and breakage taken into *** results are validated by comparing with the available experimental or numerical *** effect of Re,Φ,Sc and De on the friction factor and heat transfer of Al_(2)O_(3)/water nanofluidis *** results showed that the particle number decreases along the *** De,Sc leads to a decrease and increase ofΦ,*** mean particle diameter and particle polydispersity increase with increasing Debut with decreasing *** friction factor increases with increasingΦ,Sc De and Pr but with decreasing *** ratio of energy performance evaluation criterion(PEC)for the Al_(2)O_(3)/water nanofluid to the base fluid increases with increasing Re,Φand De,but with decreasing ***,the expression of ratio of energy PEC for the nanofluid to the base fluid as a function of Re,Φ,Sc and De is derived.

关键词： Al_(2)O_(3)/water nanofluid friction factor heat transfer energy performance evaluation turbulent pipe flow 90°bend numerical simulation

Factors influencing the short-term and long-term survival of hepatocellular carcinoma patients with portal vein tumor thrombosis who underwent chemoembolization

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World Journal of Gastroenterology 2021年第13期27卷 1330-1340页

作者： ke-Li Chen jian Gao Department of Gastroenterology and hepatology The Second Affiliated Hospital of Chongqing Medical UniversityChongqing 400010China

BACKGROUND The factors affecting the short-term and long-term prognosis of hepatocellular carcinoma(HCC) patients with portal vein tumor thrombosis(PVTT) receiving transarterial chemoembolization(TACE) are still *** To clarify the predictors correlated with the short-term and long-term survival of HCC patients with PVTT who underwent *** The medical records of 181 HCC patients with PVTT who underwent TACE at the Second Affiliated Hospital of Chongqing Medical University from January 2015 to July 2019 were retrospectively analyzed. We explored the short-term and longterm prognostic factors by comparing the preoperative indicators of patients who died and survived within 3 mo and 12 mo after TACE. Multivariate analyses were conducted using logistic regression. The area under the receiver operating characteristic curve(area under curve) was used to evaluate the predictive ability of the factors related to the short-term and long-term *** The median survival time was 4.8 mo(range: 2.5-8.85 mo). The 3 mo, 6 mo, and 12 mo survival rates were 68.5%, 38.7%, and 15.5%, respectively. In multivariable analysis, total bilirubin, sex, and aspartate aminotransferase(AST) were closely linked to short-term survival. When AST ≥ 87 U/L and total bilirubin ≥ 16.15 μmol/L, the 3-mo survival rate after TACE was reduced significantly(P he best predictive ability, followed by total bilirubin, while sex had the worst predictive ability for short-term survival area under curve: 0.763(AST) vs 0.707(total bilirubin) vs 0.554(sex)]. The long-term survival outcome was significantly better in patients with a single lesion than in those with ≥ three lesions(P = 0.009). Patients with massive block HCC had a worse long-term survival than patients with nodular and diffuse HCC(P = 0.001).CONCLUSION AST, total bilirubin, and sex are independent factors associated with short-term survival. The number of tumors and the gross pathological type of tumor are

关键词： Transarterial chemoembolization hepatocellular carcinoma Portal vein tumor thrombosis Survival Prognostic factors