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Non-invasive diagnosis of alcoholic liver disease

World Journal of Gastroenterology 2014年第40期20卷 14626-14641页

作者： Sebastian Mueller Helmut karl Seitz Vanessa Rausch Department of Internal Medicine Salem Medical Center University of Heidelberg 69121 Heidelberg Germany Center for Alcohol Research University of Heidelberg 69121 Heidelberg Germany

Alcoholic liver disease(ALD)is the most common liver disease in the Western *** many reasons,it isunderestimated and *** early diagnosis is absolutely essential since it(1)helps to identify patients at genetic risk for ALD;(2)can trigger efficient abstinence namely in non-addicted patients;and(3)initiate screening programs to prevent life-threateningcomplications such as bleeding from varices,spontaneous bacterial peritonitis or hepatocellular *** two major end points of ALD are alcoholic liver cirrhosis and the rare and clinically-defined alcoholic hepatitis(AH).The prediction and early diagnosis of both entities is still insufficiently solved and usually relies on acombination of laboratory,clinical and imaging *** is not widely conceived that conventional screeningtools for ALD such as ultrasound imaging or routine laboratory testing can easily overlook ca.40%of manifest alcoholic liver ***-invasive methods such as transient elastography(Fibroscan),acoustic radiation force impulse imaging or shear wave elastography have significantly improved the early diagnosis of *** algorithms allow either the exclusion or the exact definition of advanced fibrosis stages in ca.95%of *** correct interpretation of liver stiffness requires a timely abdominal ultrasound and actual transaminase *** non-invasive methods such as controlled attenuation parameter,serum levels of M30 or M65,susceptometry or breath tests are under current evaluation to assess the degree of steatosis,apoptosis and iron overload in these *** biopsy still remains an important option to rule out comorbidities and to confirm the prognosis namely for patients with AH.

关键词： Alcoholic hepatitis Alcoholic steatohepatitis Alcoholic liver disease Non-invasive Liver stiffness Serum marker Steatosis

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In Vitro transformation of LW13 rat liver epithelial cells

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Cell Research 1992年第2期2卷 139-152页

作者： karl LETNANSKY Shanghai Institute of Cell Biology Academia Sinica Shanghai China Institute of Applied and Experimental Oncology University of Vienna Vienna Austria

A rat liver epithelial cell line designated LW13 was es-tablished using a sequential sedimentation *** cellline retained many normal properties of liver epithelial cellsand showed some structural and functional features resem-bling those of liver parenchymal ***3 cells becamemalignant after the introduction of exogenous transformingEJ Ha ras *** produced by inoculation of thetransformed cells into baby rats contained areas of poorlydifferentiated hepatocellular *** situ hybridizationanalysis confirmed the random rather than specific integra-tion of exogenous ras gene into host ***-more,an at least tenfold increase in the expression of theendogenous c myc gene was detected among transformedcell lines,suggesting the involvement of the c myc protooncogene in the in vitro transformation of rat liver epithelialcells by EJ Ha ras oncogene.

关键词： LW13-cell line in vitro transformation EJ Ha ras integration c myc expression.

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Effective depth-of-penetration range due to hardness variation for different lots of nominally identical target material

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Defence Technology（防务技术） 2016年第2期12卷 171-176页

作者： Patrick FRUEH Andreas HEINE karl Ernst WEBER Matthias WICKERT fraunhofer EMI Eckerstrasse 479104 FreiburgGermany

The effect of small variations of target hardness on the depth of penetration for nominally identical target material has not been addressed systematically in publications yet and is often neglected. An investigation of this issue for laboratory-scale long rod projectiles penetrating into semi-infinite rolled-homogeneous-armor steel targets was conducted. The tungsten-heavy-alloy penetrators were of length 90 mm and diameter6 mm. Five lots of armor steel with a nominal hardness range of 280–330 BHN provided material for the targets. The pursued approach consisted of hardness testing of the targets, in total 17 ballistic experiments at velocities in between 1250 m/s and 1780 m/s and data analysis.A linear regression analysis of penetration vs. hardness shows that a target hardness increase within the given range of 280–330 BHN may result in a reduction of penetration depth of about 5.8 mm at constant velocity. This is equal to a change of-12% at an impact velocity of 1250 m/s. A multiple linear regression analysis included also the influence of yaw angle and impact velocity. It shows that small yaw angles and slight variations of impact velocities provide a smaller variation of the semi-infinite penetration depths than a variation of target hardness within a typical specification span of 50 BHN. For such a span a change in penetration of approximately-4.8 mm due to hardness variation is found, whereas 1°of yaw angle or-10 m/s of velocity variation gives a change of about-1.0 mm respectively-0.9 mm. For the given example, the overwhelming part of the variation is to be attributed to hardness effects – 4.8 mm out of 5.8 mm(83%). For nominally identical target material the target hardness thus influences the ballistic test results more severely than the typical scatter in impact conditions.

关键词：硬度变化渗透深度靶材料一元线性回归分析多元线性回归分析地段穿透深度冲击速度

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Distributed non-cooperative robust MPC based on reduced-order models

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Control Theory and Technology 2016年第1期14卷 11-20页

作者： Yushen LONG Shuai LIU Lihua XIE karl Henrik JOHANSSON School of Electrical and Electronic Engineering Nanyang Technological University 639798 Singapore ACCESS Linnaeus Center School of Electrical Engineering Royal Institute of Technology SE-100 44 Stockholm Sweden

In this paper, a non-cooperative distributed MPC algorithm based on reduced order model is proposed to stabilize large-scale systems. The large-scale system consists of a group of interconnected subsystems. Each subsystem can be partitioned into two parts： measurable part, whose states can be directly measured by sensors, and the unmeasurable part. In the online computation phase, only the measurable dynamics of the corresponding subsystem and neighbour-to-neighbour communication are necessary for the local controller design. Satisfaction of the state constraints and the practical stability are guaranteed while the complexity of the optimization problem is reduced. Numerical examples are given to show the effectiveness of this algorithm.

关键词： Model predictive control distributed control building energy efficiency

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Fatigue of 0.55C-1.72Si Steel with Tempered Martensitic and Carbide-Free Bainitic Microstructures

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Acta Metallurgica Sinica(English Letters) 2014年第1期27卷 55-62页

作者： Alejandro Leiro Arash Roshan karl-Gustaf Sundin Esa Vuorinen Braham Prakash Department of Engineering Sciences and Mathematics Lule University of Technology

High-Si spring steel was heat treated in three different ways： Quenching and tempering at 460 ℃ to obtain a tempered martensite microstructure, and austempering at 300 and 350 ℃, respectively, to obtain two different carbide-free bainitic microstructures. In the steel austempered at 350 ℃, both the bainite lath thickness and retained austenite content were higher than those of the steel austempered at 300 ℃. Rotating-bending fatigue tests were done in order to evaluate the effect of each heat treatment on the high-cycle fatigue behavior of the steel. When the austempering temperature was 300 ℃, the endurance limit was increased by 25% despite a 5% reduction in tensile strength when compared with that of the quenched and tempered steel. The relationship between endurance limit [Rfat （50~）] and ultimate tensile strength （Rm） was higher for the austempered samples in comparison with that of the quenched and tempered material. Therefore, it is believed that the presence of retained austenite affects the relationship between endurance limit and tensile strength.

关键词： Steels Fatigue Carbide-free bainite TRIP effect

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Compliant Mechanism Synthesis by Using Elastic Similitude

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Chinese Journal of Mechanical Engineering 2015年第4期28卷 769-775页

作者： HANKE Uwe HAMPEL Peter COMSA Andrei MODLER Niels MODLER karl-Heinz Institute of Solid Mechanics TU Dresden 01069 Dresden Germany Institute of Lightweight Engineering and Polymer Technology TU Dresden 01307 Dresden Germany

Compliant mechanisms have several advantages, especially smaller number of elements and therefore less movable joints. The flexural members furthermore allow an integration of special functions like balancing or locking. Especially fiber reinforced materials exhibit a wide range of function integration considering their compliance in passive as well active applications. To take advantage of compliant elements in applications a robust synthesis tool is needed. The synthesis based on topology optimization method or the pseudo rigid body approach leads to complex structures. Considering the use of fiber reinforced material a synthesis approach which leads to less complex structures is more suitable. For building up simple structures, with only one cantilever beam as compliant element（B） a graphical approach using the elastic similitude is the most efficient method. A step-by-step synthesis procedure is presented to synthesize compliant mechanisms with rotatory joints（R） and prismatic joints（P） to develop RRB/PRB- and RPB-linkages. Using the elastic similitude to implement these results into a graphical synthesis algorithm is the innovation part of this paper. It can be shown that this approach leads to a comfortable handling of beam elements during the synthesis, where the two free parameters can be directly coupled to scale and fix the orientation of the beam element. This advantage inherently shortens the development process. In giving an example the focus lies of the experimental approach, which also shows that the simple BERNOULLI beam model is valid and so the synthesis by using the elastic similitude. The method is presented and discussed by using an application for a cup holder mechanism made of fiber reinforced material.

关键词： Compliant mechanism synthesis elastic similitude

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Recycling of magnesium drive train components

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Science China(Technological Sciences) 2009年第1期52卷 148-154页

作者： Daniel FECHNER Carsten BLAWERT Norbert HORT karl Ulrich KAINER MagIC-Magnesium Innovation Centre GKSS Research Centre Max-Planck-Straβe 1

With the development of new heat resistant magnesium alloys, the automotive industry has introduced several parts to the drive train. The rising number of large magnesium components will result in a higher quantity of automotive post consumer scrap. It was the aim of this work to find a reasonable alloy system for the recycling of these magnesium drive train components. A matrix of potential recy-cling alloys based on the magnesium alloy AM50 was prepared via permanent mould casting. The materials were investigated via tensile testing, creep tests and salt spray tests. Three alloys were selected for processing via high pressure die casting and the tests were repeated on the new materials. A promising system for recycling has been isolated and will be investigated more deeply for the influence of impurities.

关键词： magnesium recycling end-of-life vehicles recycling alloy post consumer scrap

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Design of an innovative multi-stage forming process for a complex aeronautical thin-walled part with very small radii

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Chinese Journal of Aeronautics 2018年第11期31卷 2165-2175页

作者： Yao WANG Lihui LANG Ehsan SHERKATGHANAD karl Brian NIELSEN Chun ZHANG School of Mechanical Engineering and Automation Beihang University Department of Materials and Production Aalborg University Tianjin Tianduan Press Co. LTD

In this paper, an aeronautical thin-walled part with a complex geometry which has several sharp bends and curvatures in different directions was investigated. This kind of part is difficult to be manufactured only in one stage. Therefore, an innovative multi-stage active hydroforming process assisted by the rigid forming method was designed. In addition, an optimized blank geometry is obtained. In fact, the main focused point of this paper is to propose a new small radius rounded corner forming technique and analyze the mechanism. Two kinds of forming modes of changing a big rounded corner into a small one, which are related to different tangential positions of the die in the process of calibration, are analyzed theoretically. Meanwhile, the stress and strain states of the deformation region are compared. The relationships between the minimum relative radii of rounded corners I and II in the first stage and the hydraulic pressure are calculated by the bending theory. Finally, the influences of the tensile-bulging effect and the interface condition of the double-layer sheet on the forming quality of the specimen are investigated. The achieved results can make a foundation for utilizing the proposed method in forming of thin-walled parts with very small radii.

关键词： Double-layer sheet Hydroforming Multi-stage forming Small rounded corner Tensile-bulging effect

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Optics: learning by computing with examples using MathCAD 1

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丛书名： Undergraduate texts in contemporary physics

2003年

作者： karl Dieter Moeller

ISBN: (纸本)9780387953601;0387953604

This book is intended for a one-semester course in optics for juniors and seniors in science and engineering; it uses Mathcad(R) scripts to provide a simulated laboratory where students can learn by exploration and discovery instead of passive absorption. The text covers all the standard topics of a traditional optics course, including: geometrical optics and aberration, interference and diffraction, coherence, Maxwells equations, wave guides and propagating modes, blackbody radiation, atomic emission and lasers, optical properties of materials, Fourier transforms and FT spectroscopy, image formation, and holography. It contains step by step derivations of all basic formulas in geometrical, wave and Fourier optics. The basic text is supplemented by over 170 Mathcad files, each suggesting programs to solve a particular problem, and each linked to a topic in or application of optics. The computer files are dynamic, allowing the reader to see instantly the effects of changing parameters in the equations. Students are thus encouraged to ask'what... if'questions to assess the physical implications of the formulas.

关键词： Geometrical optics

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MEMS-actuated metasurface Alvarez lens

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Microsystems & Nanoengineering 2020年第1期6卷 334-344页

作者： Zheyi Han Shane Colburn Arka Majumdar karl F.Bohringer Department of Electrical and Computer Engineering University of WashingtonSeattleWashington 98195USA Institute for Nano-Engineered Systems University of WashingtonSeattleWashington 98195USA Department of Physics University of WashingtonSeattleWashington 98195USA Department of Bioengineering University of WashingtonSeattleWashington 98195USA

Miniature lenses with a tunable focus are essential components for many modern applications involving compact optical *** several tunable lenses have been reported with various tuning mechanisms,they often face challenges with respect to power consumption,tuning speed,fabrication cost,or production *** this work,we have adapted the mechanism of an Alvarez lens–a varifocal composite lens in which lateral shifts of two optical elements with cubic phase surfaces give rise to a change in the optical power–to construct a miniature,microelectromechanical system(MEMS)-actuated metasurface Alvarez *** based on an electrostatic MEMS generates fast and controllable actuation with low power *** utilization of metasurfaces–ultrathin and subwavelength-patterned diffractive optics–as optical elements greatly reduces the device volume compared to systems using conventional freeform *** entire MEMS Alvarez metalens is fully compatible with modern semiconductor fabrication technologies,granting it the potential to be mass-produced at a low unit *** the reported prototype operating at 1550 nm wavelength,a total uniaxial displacement of 6.3µm was achieved in the Alvarez metalens with a direct-current(DC)voltage application up to 20V,which modulated the focal position within a total tuning range of 68µm,producing more than an order of magnitude change in the focal length and a 1460-diopter change in the optical *** MEMS Alvarez metalens has a robust design that can potentially generate a much larger tuning range without substantially increasing the device volume or energy consumption,making it desirable for a wide range of imaging and display applications.

关键词： electrostatic optics adapted

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