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对高危冠状动脉搭桥术患者施行单次交叉钳夹可改善6个月认知预后:简化主动脉操作的效果

世界核心医学期刊文摘（心脏病学分册） 2006年第5期2卷 58-59页

作者： Hammon j.W Stump D.A butterworth j.f. 刘少伟 Departm ent of Cardiothoracic Surgery Wake Forest University Health Sciences Medical Center Blvd Winston-Salem NC 27157 United StatesDr.

Objective: We hypothesized that a strategy that reduced aortic manipulation would reduce the incidence of cognitive deficits in patients undergoing coronary artery bypass grafting compared with the “ traditional” approach and that neurobehavioral outcomes with the reduced aortic manipulation strategy would approach those obtained with off-pump coronary artery bypass surgery. Methods: Consenting high-risk patients(those with older age, diabetes, or hypertension) scheduled for coronary artery bypass grafting and cardiopulmonary bypass were randomly assigned to 1 of 2 aortic management protocols:(1) a traditional approach in which distal anastomoses were accomplished while the aorta was crossclamped but in which proximal anastomoses were sewn while a partial occlusion clamp was applied to the aorta(multiple aortic clamping group) or(2) a reduced aortic manipulation approach in which the aorta was clamped a single time with a reduced-pressure clamp(single aortic clamping group) and the partial occlusion clamp was not used. A contemporaneous group of patients undergoing off-pump coronary artery bypass surgery without cardiopulmonary bypass was also enrolled. Subjects in all 3 groups underwent neurologic and neuropsychological testing before and after surgery. After randomization, patients assigned to either approach could be changed to another strategy if the attending surgeon determined that patient safety demanded this change. The study design anticipated that surgical techniques would evolve over the course of patient enrollment and anticipated that some patients would have intraoperative echocardiographic findings that would demand that the traditional approach(eg, severe aortic atherosclerosis) or the reduced manipulation protocol(eg, severe ischemia or poor left ventricular function) be abandoned. Thus, an unequal distribution of patients was expected. By surgeon decision, 20 of 84 multiple aortic clamping patients crossed over to single aortic clamping, and 3 of 8

关键词：非体外循环下冠状动脉搭桥术主动脉粥样硬化认知功能缺陷高危患者操作法钳夹预后单次神经心理学测试传统术式

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Some micromechanical models of elastoplastic behaviors of porous geomaterials

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journal of Rock Mechanics and Geotechnical Engineering 2017年第1期9卷 1-17页

作者： W.Q. Shen j.f. Shao Laboratory of Mechanics of Lille University of Lille I Villeneuve d’Ascq 59655 France

Some micromechanics-based constitutive models are presented in this study for porous *** micro-macro mechanical models focus on the effect of porosity and the inclusions on the macroscopic elastoplastic behaviors of porous materials. In order to consider the effect of pores and the compressibility of the matrix, some macroscopic criteria are presented firstly for ductile porous medium having one population of pores with different types of matrix(von Mises, Green type, Misese Schleicher and Druckere Prager). Based on different homogenization techniques, these models are extended to the double porous materials with two populations of pores at different scales and a Druckere Prager solid phase at the microscale. Based on these macroscopic criteria, complete constitutive models are formulated and implemented to describe the overall responses of typical porous geomaterials(sandstone,porous chalk and argillite). Comparisons between the numerical predictions and experimental data with different confining pressures or different mineralogical composites show the capabilities of these micromechanics-based models, which take into account the effects of microstructure on the macroscopic behavior and significantly improve the phenomenological ones.

关键词： Homogenization Porous geomaterials Ductile behavior Double porosity Macroscopic strength Plastic compressibility Druckere Prager solids

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Quantified evaluation of particle shape effects from micro-to-macro scales for non-convex grains

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Particuology 2016年第2期14卷 23-35页

作者： Y. Yang j.f. Wang Y.M. Cheng Department of Civil and Environmental Engineering The Hong Kong Polytechnic University Hong Kong China Department of Civil and Architectural Engineering City University of Hong Kong Hong Kong China

Particle shape plays an important role in both the micro and macro scales responses of a granular assem- bly. This paper presents a systematic way to interpret the shape effects of granular material during quasi-static shearing. A more suitable shape descriptor is suggested for the quantitative analysis of the macroscale strength indexes and contact parameters for non-convex grains, with special consid- eration given to the peak state and critical state. Through a series of numerical simulations and related post-processing analysis, particle shape is found to directly influence the strain localisation patterns, microscale fabric distributions, microscale mobilisation indexes, and probability distribution of the nor- malised contact normal force. Additionally, the accuracy of the stress-force-fabric relationship can be influenced by the average normal force and the distribution of contact vectors. Moreover, particle shape plays a more important role than do the confining pressures in determining the friction angle. Strong force chains and the dilation effect are also found to be strongly influenced by the high confinin~ oressure.

关键词： Quantitative analysis Shape factor Statistical analysis Micro-macro indexes

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A NOVEL APPROACH fOR THE PREDICTION Of SURfACE PROfILE Of OUTGOING WORKPIECE AND THE CALCULATION Of MEAN ROLL RADIUS IN ALLOY BAR ROLLING

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Acta Metallurgica Sinica(English Letters) 2007年第1期20卷 49-58页

作者： Y.G. Dong W.Z. Zhang j.f. Song College of Mechanical Engineering Yanshan University Qinhuangdao 066004 Ghina College of Electromechanical Engineering Harbin Institute of Technology Harbin 150001China

In alloy bar rolling process, the component of alloyed steel influenced the spread coefficient greatly, therefore, the component influence coefficient m of different alloyed steel has been determined firstly to calculate the maximum spread. Then the curvature radius of stress free surface and the ＂critical point on the contact boundary＂ have been solved, the surface profile of outgoing workpiece has been obtained. furthermore, the formula of the equivalent contact section area has been proposed and the mean roll radius has been calculated. The bar rolling experiment and the rigid-plastic fEM （finite element method） simulation have been carried out to verify the novel approach. Compared with experimental data and simulation results, the novel approach can be used in setting processing parameter and design of finishing groove.

关键词： alloyed steel surface profile mean roll radius critical point rigid-plastic fEM (finite element method)

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HIGH-TEMPERATURE LOW-CYCLE fATIGUE BEHAVIOR Of NICKEL-BASED SUPERALLOY GH4049

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Acta Metallurgica Sinica(English Letters) 1999年第1期12卷 12-15页

作者： Chen, L.j. Yao, G. Wang, Z.G. Tian, j.f. Inst of Metal Research The Chinese Acad of Sciences Shenyang China

The cyclic stress response and lowcycle fatigue life for wrought nickelbased superalloy GH4049 were investigated in the temperature range from 500 to 800 The relationship between the strain amplitude and the number of stress reversals was given. The behavior of cyclic hardening was observed for higher strain amplitudes at all testing temperatures and the lowcycle fatigue life generally decreased with increasing testing temperature for the same strain range. In addition, fracture surfaces of the fatigued samples were examined by using a scanning electron microscope.

关键词： superalloy low cycle fatigue fatigue life

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Comparison of artificial neural networks with empirical correlations for estimating the average cycle time in conical spouted beds

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Particuology 2019年第1期17卷 48-57页

作者： I. Estiatia M. Tellabidea j.f. Saldarriaga H. Altzibara f.B. freirec j.T. freirec M. Olazara Department of Chemical Engineering University of the Basque CountryP.O. box 644E48080 BilbaoSpain Department of Civil and Environmental Engineering Universidad de los AndesCr.1 Este 19A-40BogotaColombia Department of Chemical Engineering Federal University of Sao CarlosRod. Washington Luis-km 235P.O. box 67613565-905Sao CarlosSPBrazil

Conventional spouted beds have been extensively used in many real-life applications but are not suited for all types of materials, especially fine particles, which require internal devices to improve their motion in the spouted bed. However, unlike conventional spouted beds, there are almost no mechanistic or empirical models available for the design of spouted beds with internals. Given the availability of an extensive but not experimentally designed database, the main purpose of this study is to present an analysis of neural networks and empirical models in terms of their suitability to fit and predict average cycle times in conical spouted beds with and without draft tubes. The parameters investigated are particle size, density, contactor angle, gas inlet diameter, static bed height, and draft tube features. Although the amount of information is always a key factor when fitting models, the size of the database used in this study strongly affects the fitting performance of empirical models, whereas artificial neural networks are more influenced by how the data are scaled. Results of model verification show that both techniques are suitable for predicting average cycle times for data outside the range covered by the database.

关键词： Empirical correlation Artificial neural network Average cycle time Conical spouted bed Draft tubes Modeling

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Distribution and mode of occurrence of radionuclides in phosphogypsum derived from Aqaba and Eshidiya fertilizer Industry,South jordan

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Chinese journal Of Geochemistry 2010年第3期29卷 261-269页

作者： Al-Hwaiti M.S. Zielinski R.A. Bundham j.R. Ranville j.f. Ross P.E. Environmental Engineering Department Al-Hussein Bin Talal University USGS DenverCO 80225USA Environmental Science and Engineering Division Colorado School of Mines

Phosphogypsum (PG) is a by-product of the chemical reaction called the "wet process" whereby sul-phuric acid reacts with phosphate rock (PR) to produce phosphoric acid, needed for fertilizer production. Through the wet process, some impurities naturally present in the PR become incorporated in PG, including U decay-series radionuclides, are the main important concern which could have an effect on the surrounding environment and pre-vent its safe utilization. In order to determine the distribution and bioavailability of radionuclides to the surrounding environment, we used a sequential leaching of PG samples from Aqaba and Eshidiya fertilizer industry. The results showed that the percentages of 226Ra and 210Pb in PG are over those in the corresponding phosphate rocks (PG/PR), where 85% of the 226Ra and 85% of the 210Pb fractionate to PG. The sequential extraction results exhibited that most of 226Ra and 210Pb are bound in the residual phase (non-CaSO4) fraction ranging from 45%-65% and 55%-75%, respectively, whereas only 10%-15% and 10%-20% respectively of these radionuclides are distributed in the most labile fraction. The results obtained from this study showed that radionuclides are not incorporated with gypsum itself and may not form a threat to the surrounding environment.

关键词：天然放射性核素磷石膏化肥工业赋存状态 226Ra 反应产物化肥生产周围环境

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基于Modular网络和EM-SfM算法的模糊Sugeno模型(英文)

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控制理论与应用 2001年第3期18卷 333-340页

作者：王士同 j.f.鲍尔蕴 T.马丁华东船舶工业学院计算机系江苏镇江212003 布里斯托尔大学高级计算机研究中心英国布里斯托尔布里斯托尔大学高级计算机研究中心

基于Modular网络重新解释了广为使用的模糊Sugeno模型 .随后 ,基于EM算法 ,提出了该模型的新算法EM SfM ,证明了该算法的线性收敛法 ,分析了它的收敛速度 .

关键词：模糊Sugeno模型 Modular网络收敛 EM-SfM算法人工智能

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漂亮女人

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当代电影 1993年第3期 97-129页

作者： j.f.劳顿东方

下午刘易斯股份有限公司洛杉矶分公司兼菲利普律师事务所大平台三面被绿树环绕,几张铺着玫瑰色台布的桌子上摆满各种饮料及酒水,几只圆瓷瓶中插着鲜花。这里正在举行招待会。男男女女的宾客们衣冠楚楚,三五一群地谈笑着。几位客人围在... 详细信息

下午刘易斯股份有限公司洛杉矶分公司兼菲利普律师事务所大平台三面被绿树环绕,几张铺着玫瑰色台布的桌子上摆满各种饮料及酒水,几只圆瓷瓶中插着鲜花。这里正在举行招待会。男男女女的宾客们衣冠楚楚,三五一群地谈笑着。几位客人围在一个男子周围看他变魔术。“不管他们怎么说,都是钱在作怪。假如你们是搞储蓄贷款的,女士们……”那男人将一枚金币放在站在他右侧的女人手上,又将另外三枚放在左侧的女人手上,并且一个一个地数着:“瞧,一、二、三……”然后,把她的手合上,拿起右侧女人手中的那枚金币,攥在自己手中,马上又张开,里面的金币不见了。“

关键词：爱德华衣服菲利普亚当斯首饰盒汤姆逊非尔刘易斯莫尔斯纽约

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Postoperative complications and weight loss following jejunostomy tube feeding after total gastrectomy for advanced adenocarcinomas

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Chinese journal of Cancer Research 2017年第4期29卷 333-340页

作者： Hylke j.f. Brenkman Stephanie V.S. Roelen Elles Steenhagen jelle P. Ruurda Richard van Hillegersberg Cancer Center Department of Surgery University Medical Center Utrecht PO Box 85500 3508 GA Utrecht the Netherlands Internal Medicine and Dermatology Department of Dietetics University Medical Center Utrecht PO Box 85500 3508 GA Utrecht the Netherlands Correspondence to R van Hillegersberg MD PhD. Department of Surgery University Medical Centre Utrecht G04.228 PO Box 85500 3508 GA

Objective： Patients undergoing total gastrectomy for cancer are at risk of malnourishment. The aim of this self- controlled study was to examine the effect of jejunostomy tube feeding （j.f. and other factors on postoperative weight and the incidence of jejunostomy-related complications in patients undergoing total gastrectomy for cancer. Methods： All consecutive patients who underwent total gastrectomy for gastric cancer with jejunostomy plaeement were included from a prospective single-center database （2003-2014）. jejunostomy-related complications and postoperative weight changes were evaluated up to 12 months after surgery. Multivariable linear regression analysis was performed to identify factors associated with weight loss 12 months after gastreetomy. Results： Of 113 patients operated in the study period, 65 received j.f.after total gastrectomy for a median duration of 18 d [interquartile range （IQR）, 10-55 d]. jejunostomy-related complieations occurred in 11 （17%） patients, including skin leakage （n=3） and peritoneal leakage （n=2）, luxation （n=3）, occlusion （n=2）, infection （n=l） and torsion （n=l）. In 2 （3%） patients, a reoperation was needed due to jejtmostomy-related complications. The mean preoperative weight of patients was 71.8 kg （100%）, and remained stable during j.f.（73.9 kg, 103%, P=0.331）. After j.f.was stopped, the mean weight of patients decreased to 64.9 kg （90%） at 12 months after surgery （P〈0.001）. A high preoperative body mass index （BMI）（〉_25 kg/m2） was associated with high postoperative weight loss compared to patients with a low BMI （〈25 kg/m2）（16.3% vs. 8.6%, P=0.016）. Conclusions： j.f.can prevent weight loss in the early postoperative phase. However, this is at the prize of possible complications. As weight loss in the long term is not prevented, routine j.f.should be re-evaluated and balanced against the selected use in preoperatively malnourished patients. Special attention should be paid to patients with a high preoperative BMI, who ar

关键词： Gastric cancer total gastrectomy jejunostomy tube feeding weight

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