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Sample records for von mises stress

  1. Determining the von Mises stress power spectral density for frequency domain fatigue analysis including out-of-phase stress components

    NARCIS (Netherlands)

    Bonte, M.H.A.; de Boer, Andries; Liebregts, R.

    This paper provides a new formula to take into account phase differences in the determination of an equivalent von Mises stress power spectral density (PSD) from multiple random inputs. The obtained von Mises PSD can subsequently be used for fatigue analysis. The formula was derived for use in the

  2. UOE Pipe Numerical Model: Manufacturing Process And Von Mises Residual Stresses Resulted After Each Technological Step

    Science.gov (United States)

    Delistoian, Dmitri; Chirchor, Mihael

    2017-12-01

    Fluid transportation from production areas to final customer is effectuated by pipelines. For oil and gas industry, pipeline safety and reliability represents a priority. From this reason, pipe quality guarantee directly influence pipeline designed life, but first of all protects environment. A significant number of longitudinally welded pipes, for onshore/offshore pipelines, are manufactured by UOE method. This method is based on cold forming. In present study, using finite element method is modeled UOE pipe manufacturing process and is obtained von Mises stresses for each step. Numerical simulation is performed for L415 MB (X60) steel plate with 7,9 mm thickness, length 30 mm and width 1250mm, as result it is obtained a DN 400 pipe.

  3. Combined shape and topology optimization for minimization of maximal von Mises stress

    DEFF Research Database (Denmark)

    Lian, Haojie; Christiansen, Asger Nyman; Tortorelli, Daniel A.

    2017-01-01

    This work shows that a combined shape and topology optimization method can produce optimal 2D designs with minimal stress subject to a volume constraint. The method represents the surface explicitly and discretizes the domain into a simplicial complex which adapts both structural shape and topology...

  4. Probability distribution of von Mises stress in the presence of pre-load.

    Energy Technology Data Exchange (ETDEWEB)

    Segalman, Daniel Joseph; Field, Richard V.,; Reese, Garth M.

    2013-04-01

    Random vibration under preload is important in multiple endeavors, including those involving launch and re-entry. There are some methods in the literature to begin to address this problem, but there is nothing that accommodates the existence of preloads and the necessity of making probabilistic statements about the stress levels likely to be encountered. An approach to achieve to this goal is presented along with several simple illustrations.

  5. High dimensional Bernstein-von Mises: simple examples

    OpenAIRE

    Johnstone, Iain M.

    2010-01-01

    In Gaussian sequence models with Gaussian priors, we develop some simple examples to illustrate three perspectives on matching of posterior and frequentist probabilities when the dimension p increases with sample size n: (i) convergence of joint posterior distributions, (ii) behavior of a non-linear functional: squared error loss, and (iii) estimation of linear functionals. The three settings are progressively less demanding in terms of conditions needed for validity of the Bernstein-von Mise...

  6. The Multivariate Generalised von Mises Distribution: Inference and Applications

    DEFF Research Database (Denmark)

    Navarro, Alexandre Khae Wu; Frellsen, Jes; Turner, Richard

    2017-01-01

    . These models can leverage standard modelling tools (e.g. kernel functions and automatic relevance determination). Third, we show that the posterior distribution in these models is a mGvM distribution which enables development of an efficient variational free-energy scheme for performing approximate inference...... to the circular domain. First we introduce a new multivariate distribution over circular variables, called the multivariate Generalised von Mises (mGvM) distribution. This distribution can be constructed by restricting and renormalising a general multivariate Gaussian distribution to the unit hyper...

  7. VON MISES-FISHER MIXTURE MODEL OF THE DIFFUSION ODF

    Science.gov (United States)

    McGraw, Tim; Vemuri, Baba C.; Yezierski, Bob; Mareci, Thomas

    2009-01-01

    High angular resolution diffusion imaging (HARDI) permits the computation of water molecule displacement probabilities over the sphere. This probability is often referred to as the orientation distribution function (ODF). In this paper we present a novel model for representing this diffusion ODF namely, a mixture of von Mises-Fisher (vMF) distributions. Our model is compact in that it requires very few parameters to represent complicated ODF geometries which occur specifically in the presence of heterogeneous nerve fiber orientations. We present a Riemannian geometric framework for computing intrinsic distances (in closed-form) and for performing interpolation between ODFs represented by vMF mixtures. We also present closed-form equations for entropy and variance based anisotropy measures that are then computed and illustrated for real HARDI data from a rat brain. PMID:19759891

  8. FEM and Von Mises Analysis on Prosthetic Crowns Structural Elements: Evaluation of Different Applied Materials

    Directory of Open Access Journals (Sweden)

    Ennio Bramanti

    2017-01-01

    Full Text Available The aim of this paper is to underline the mechanical properties of dental single crown prosthodontics materials in order to differentiate the possibility of using each material for typical clinical condition and masticatory load. Objective of the investigation is to highlight the stress distribution over different common dental crowns by using computer-aided design software and a three-dimensional virtual model. By using engineering systems of analyses like FEM and Von Mises investigations it has been highlighted the strength over simulated lower first premolar crowns made by chrome cobalt alloy, golden alloy, dental resin, and zirconia. The prosthodontics crown models have been created and put on simulated chewing stresses. The three-dimensional models were subjected to axial and oblique forces and both guaranteed expected results over simulated masticatory cycle. Dental resin presented the low value of fracture while high values have been recorded for the metal alloy and zirconia. Clinicians should choose the better prosthetic solution for the teeth they want to restore and replace. Both prosthetic dental crowns offer long-term success if applied following the manufacture guide limitations and suggestions.

  9. Critical assessment of von Mises distribution and an infinite series ansatz for self-propelled particles

    Science.gov (United States)

    Kürsten, Rüdiger; Ihle, Thomas

    2017-03-01

    We consider a Vicsek model of self-propelled particles with bounded confidence, where each particle interacts only with neighbors that have a similar direction. Depending on parameters, the system exhibits a continuous or discontinuous polar phase transition from the isotropic phase to a phase with a preferred direction. In a recent paper (Lam, Schindler and Dauchot 2015 J. Stat. Mech. P10017) the von Mises distribution was proposed as an ansatz for polar ordering. In the present system the time evolution of the angular distribution can be solved in Fourier space. We compare the results of the Fourier analysis with the ones obtained by using the von Mises distribution ansatz. In the latter case the qualitative behavior of the system is recovered correctly. However, quantitatively there are serious deviations. We introduce an extended von Mises distribution ansatz such that a second term takes care of the next two Fourier modes. With the extended ansatz we find much better quantitative agreement. As an alternative approach we also use a Gaussian and a geometric series ansatz in Fourier space. The geometric series ansatz is analytically handable but fails for very weak noise, the Gaussian ansatz yields better results but it is not analytically treatable.

  10. Infinite von Mises-Fisher Mixture Modeling of Whole Brain fMRI Data

    DEFF Research Database (Denmark)

    Røge, Rasmus; Madsen, Kristoffer Hougaard; Schmidt, Mikkel Nørgaard

    2017-01-01

    Cluster analysis of functional magnetic resonance imaging (fMRI) data is often performed using gaussian mixture models, but when the time series are standardized such that the data reside on a hypersphere, this modeling assumption is questionable. The consequences of ignoring the underlying...... spherical manifold are rarely analyzed, in part due to the computational challenges imposed by directional statistics. In this letter, we discuss a Bayesian von Mises-Fisher (vMF) mixture model for data on the unit hypersphere and present an efficient inference procedure based on collapsed Markov chain...... Monte Carlo sampling. Comparing the vMF and gaussian mixture models on synthetic data, we demonstrate that the vMF model has a slight advantage inferring the true underlying clustering when compared to gaussian-based models on data generated from both a mixture of vMFs and a mixture of gaussians...

  11. Correlation between von Mises strain and material thinning in a hydroformed sample of Ti35A aerospace grade titanium

    Science.gov (United States)

    Bell, Colin; Jump, Ellen; Kerr, William; Corney, Jonathan; Zuelli, Nicola; Savings, David

    2017-10-01

    This paper presents the results of an experimental investigation of the strain measured on a sample of Ti35A (commercially pure) titanium that was formed past the point of failure in a hydroforming operation. The sample was etched prior to forming to allow for a strain map of the exterior to be created and examined by using a circle grid analysis (CGA) technique. The sample was scanned post forming with precise optical inspection to ascertain an accurate model of its geometry. This paper discusses the results of the analyses including the full geometric and surface strain measurements. This paper then compares material thinning properties to strain values and finds a linear relationship of approximately 3:1 between Von Mises strain and material thinning percentage throughout the sample. The slope of the line appears to correlate strongly with the material's Poisson's ratio and could have potential uses in process planning.

  12. Systemisch-lösungsorientierte Beratung zur Prävention von Stress und Burnout in Pflegeberufen

    OpenAIRE

    Abel, Christoph

    2007-01-01

    Aktuelle Forschungsergebnisse aus dem Salutogenese-Ansatz betonen die Rolle von Selbstregulation und Autonomie als personenbezogene Ressourcen gegen Stress und Burnout. Die Arbeit möchte einen Beitrag zur Qualifizierung von Beschäftigten in Pflegeberufen leisten. Es wurde eine Trainingsmaßnahme zur Prävention von Stress und Burnout evaluiert, innerhalb derer die Probanden eine Einführung in die systemisch-lösungsorientierte Beratung erhalten.

  13. Preliminary intraobserver and interobserver variability in wall stress and rupture risk assessment of abdominal aortic aneurysms using a semiautomatic finite element model.

    Science.gov (United States)

    Teutelink, Arno; Cancrinus, Ernst; van de Heuvel, Danyel; Moll, Frans; de Vries, Jean-Paul

    2012-02-01

    We investigated the intraobserver and interobserver variability of using semiautomatic finite element analysis to calculate the von Mises stress and peak wall rupture risk (PWRR) in patients with an abdominal aortic aneurysm (AAA) in longitudinal studies. Four independent observers made 3-dimensional (3D) reconstructions, with minimal manual adjustments, of small AAAs (method was used to calculate von Mises stress and PWRR, which are indicators for wall stress. The differences of each pair of measurements of von Mises stress and PWRR were plotted against their mean and the difference of the mean, according to Bland-Altman analysis. The intraobserver variability had an overall mean percentage difference of 6.86% ± 6.46% for the von Mises stress and 7.70% ± 6.26% for PWRR. The interobserver variability for the four observers showed an overall mean percentage difference of 7.09% ± 6.16% for the von Mises stress and 9.47% ± 8.18% for the PWRR measurement. No significant differences were found (P calculated in this semiautomatic finite element analysis program show good interobserver and intraobserver variability. It is suitable for clinical use to evaluate mechanical aortic wall characteristics and to compare it with other current methods such as maximum aortic diameter measurements. Copyright © 2012 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.

  14. Numerical investigation on effect of aortic root geometry on flow induced structural stresses developed in a bileaflet mechanical heart valve

    Science.gov (United States)

    Abbas, S. S.; Nasif, M. S.; Said, M. A. M.; Kadhim, S. K.

    2017-10-01

    Structural stresses developed in an artificial bileaflet mechanical heart valve (BMHV) due to pulsed blood flow may cause valve failure due to yielding. In this paper, von-Mises stresses are computed and compared for BMHV placed in two types of aortic root geometries that are aortic root with axisymmetric sinuses and with axisymmetric bulb, at different physiological blood flow rates. With BMHV placed in an aortic root with axisymmetric sinuses, the von-Mises stresses developed in the valve were found to be up to 47% higher than BMHV placed in aortic root with axisymmetric bulb under similar physiological conditions. High velocity vectors and therefore high von-Mises stresses have been observed for BMHV placed in aortic root with axisymmetric sinuses, that can lead to valve failure.

  15. Environmental stress cracking causes severe failures in plastic parts; Das Spannungsrissverhalten von Kunststoffen - ein unterschaetzter Versagensmechanismus?

    Energy Technology Data Exchange (ETDEWEB)

    Schmachtenberg, E. [Institut fuer Kunststoffe im Maschinenbau, Universitaet GH Essen (Germany); Schoeche, N. [Institut fuer Kunststoffe im Maschinenbau, Bereich Werkstofftechnik, Universitaet GH Essen (Germany)

    1994-12-31

    Environmental stress cracking causes severe failures in plastic parts. In practice the reduction of the failure risk by design is complicated by a lack of standard characterisation data and a generally accepted interpretation criterion. This article describes the state of art in testing environmental stress cracking and the potential of standardization. (orig.) [Deutsch] Spannungsrissbildung ist eine haeufige Versagensursache von Kunststoffbauteilen. In der Konstruktion wird dieser Umstand jedoch nicht angemessen beruecksichtigt, weil einheitliche Kennwerte und ein allgemein anerkanntes Bewertungskriterium fehlen. In diesem Beitrag wird deshalb auf die gaengigen Pruefverfahren zur Charakterisierung des Spannungsrissverhaltens eingegangen und das Potential fuer eine Standardisierung aufgezeigt. (orig.)

  16. Finite element analysis of thermal stress distribution in different restorative materials used in class V cavities.

    Science.gov (United States)

    Guler, M S; Guler, C; Cakici, F; Cakici, E B; Sen, S

    2016-01-01

    Cervical lesions are restored with class V preparation. The aim of this study was to use a three-dimensional finite element method to carry out a thermal analysis of the temperature and stress distributions of three different restorative materials used for class V cavities of maxillary molar teeth. A maxillary left first molar tooth was modeled and a class V cavity was prepared on the cervical 1/3 of the buccal surface. This cavity was restored with three different materials (Group I: Resin composite, Group II: Glass ionomer cement, and Group III: Amalgam). Loads of 400 N were applied at an angle of 90° to the longitudinal axis of the tooth on the restorative material at 5 and 55°C temperatures. Von Mises and thermal stress distributions were evaluated. In all groups, the von Mises stress values increased with temperature. The highest von Mises stress distribution was observed at 55°C in Group II (144.53 MPa). The lowest von Mises stress distribution was observed at 5°C in Group III (70.81 MPa). Amalgam is the most suitable restorative material for class V restorations because of minimal stress distribution.

  17. Mise au point

    African Journals Online (AJOL)

    of the skull base secondary to generalized enchondromatosis: a case report and review of the literature. ear nose Throat j. 201; 90:535-7. 5- Chbani L, Znati k, el Fatemi H, Harmouch T, Zaki Z, Bennis S, amarti a. Chondrosarcome de la cloison nasale. rev Stomatol Chir maxillofac. 2007;108:231-233. journal OrL n°29:mise ...

  18. Mise au point

    African Journals Online (AJOL)

    confection du lambeau à la pince et son sacrifice par la suite, une ostéotomie réalisée à l'aide de la fraise et enfin, une mise en place d'une sonde bicanaliculonasale (BCn) dans 98% des opérations (Figures 1-7). Figure 1: Cathétérisme du canalicule inférieur avec une endolumière 25 G afin d'obtenir la transillumination ...

  19. Stress distribution of oval and circular fiber posts in amandibular premolar: a three-dimensional finite element analysis.

    Science.gov (United States)

    Er, Ozgur; Kilic, Kerem; Esim, Emir; Aslan, Tugrul; Kilinc, Halil Ibrahim; Yildirim, Sahin

    2013-11-01

    The aim of the present study was to evaluate the effects of posts with different morphologies on stress distribution in an endodontically treated mandibular premolar by using finite element models (FEMs). A mandibular premolar was modeled using the ANSYS software program. Two models were created to represent circular and oval fiber posts in this tooth model. An oblique force of 300 N was applied at an angle of 45° to the occlusal plane and oriented toward the buccal side. von Mises stress was measured in three regions each for oval and circular fiber posts. FEM analysis showed that the von Mises stress of the circular fiber post (426.81 MPa) was greater than that of the oval fiber post (346.34 MPa). The maximum distribution of von Mises stress was in the luting agent in both groups. Additionally, von Mises stresses accumulated in the coronal third of root dentin, close to the post space in both groups. Oval fiber posts are preferable to circular fiber posts in oval-shaped canals given the stress distribution at the post-dentin interface.

  20. On a comparison of Huber-Mises-Hencky with Burzynski-Pecherski equivalent stresses for glass body during nonstationary thermal load

    Science.gov (United States)

    Badur, Janusz; Bryk, Mateusz; Ziolkowski, Pawel; Slawinski, Daniel; Ziolkowski, Piotr; Kornet, Sebastian; Stajnke, Michal

    2017-03-01

    Glass materials are constantly the base of life the majority of society. A lot of us, every morning brew a cup of tea or coffee in his favourite cup or look out glass pane in order to define the weather outside. Examples can be multiplied and multiplied. On account the role of glass materials, in most people life, has been decided to choice a glass material as a base to perform thermal FSI analysis. However the analysis would be nothing without calculative model. It is well known that there are various strength hypothesis, which treat of material strength dependency on reduced tension. In most cases, to the issue which is related to reduced tensions appointment which appear in analysed material, the Huber-Mises-Hencky hypothesis is used, but it is difficult to model glass material by this hypothesis. It happens because of specific properties of glass, which is amorphous body. And here, with help occurs the W.Burzynski, Huber's student. Burzynski proposed the following reduced tension definition: Φf+η (p )ṡΦv=K , from which the Burzynski material effort is calculated:σB=1/2 k ṡ[ -(k -1 )ṡσm+√{(k-1 ) 2ṡσm2+4 ṡk ṡσHM H 2 } ] . We reached to the idea, which is the introduction of material properties coefficient k. This parameter describes the relation of compressing strength to the tensile strength. Furthermore, R. Pecherski proposed the Burzynski hypothesis enlargement by Lode's angle influence, which controls the participation of the energy density of distortion. Finally the Burzynski-Pecherski hypothesis is: η˜f(θ )ϕf+η˜v(p )ϕv=K . Where θ describes Lode's angle. In this work is presented the comparison of aforementioned hypothesis and delimitation the differences in received results stresses values by each one of hypothesis. As example of analysed problem the cold glass cup under nonstationary thermal load (which is simulated by boiled water) is taken under consideration. The analysis consist of flow calculations, bounded with filling

  1. Determination of short circuit stresses in an air core reactor using ...

    African Journals Online (AJOL)

    DR OKE

    withstood the short circuit test. Keywords: Reactor, Short circuit forces, von Mises stress, Finite Element Method, Inductor ... The value of initial current depends on the instant of switching the circuit. At switching instant t = 0, .... electrical equipments such as transformer, generators, motors etc. The method can be used to ...

  2. Stress distribution in maxillary first molar periodontium using straight pull headgear with vertical and horizontal tubes: A finite element analysis.

    Science.gov (United States)

    Feizbakhsh, Masood; Kadkhodaei, Mahmoud; Zandian, Dana; Hosseinpour, Zahra

    2017-01-01

    One of the most effective ways for distal movement of molars to treat Class II malocclusion is using extraoral force through a headgear device. The purpose of this study was the comparison of stress distribution in maxillary first molar periodontium using straight pull headgear in vertical and horizontal tubes through finite element method. Based on the real geometry model, a basic model of the first molar and maxillary bone was obtained using three-dimensional imaging of the skull. After the geometric modeling of periodontium components through CATIA software and the definition of mechanical properties and element classification, a force of 150 g for each headgear was defined in ABAQUS software. Consequently, Von Mises and Principal stresses were evaluated. The statistical analysis was performed using T-paired and Wilcoxon nonparametric tests. Extension of areas with Von Mises and Principal stresses utilizing straight pull headgear with a vertical tube was not different from that of using a horizontal tube, but the numerical value of the Von Mises stress in the vertical tube was significantly reduced ( P 0/05). Based on the results, when force applied to the straight pull headgear with a vertical tube, Von Mises stress was reduced significantly in comparison with the horizontal tube. Therefore, to correct the mesiolingual movement of the maxillary first molar, vertical headgear tube is recommended.

  3. Mise au point

    African Journals Online (AJOL)

    31 mai 2013 ... patients 25,6% dont 2 inaugurales et 18 diabétiques étaient en décompensation acido-cétosiques (DaC) 23,. 1% aucun de nos patients n'était immunodéprimé. Bactériologie. L'étude bactériologique du liquide de drainage était réali- sée chez 26 patients33, 4%, elle a mise en évidence une. J. tun ORL - n° ...

  4. Stress distribution in maxillary first molar periodontium using straight pull headgear with vertical and horizontal tubes: A finite element analysis

    Directory of Open Access Journals (Sweden)

    Masood Feizbakhsh

    2017-01-01

    Conclusion: Based on the results, when force applied to the straight pull headgear with a vertical tube, Von Mises stress was reduced significantly in comparison with the horizontal tube. Therefore, to correct the mesiolingual movement of the maxillary first molar, vertical headgear tube is recommended.

  5. Finite element analysis of stress distribution in four different endodontic post systems in a model canine.

    Science.gov (United States)

    Chen, Aijie; Feng, Xiaoli; Zhang, Yanli; Liu, Ruoyu; Shao, Longquan

    2015-01-01

    To investigate the stress distribution in a maxillary canine restored with each of four different post systems at different levels of alveolar bone loss. Two-dimensional finite element analysis (FEA) was performed by modeling a severely damaged canine with four different post systems: CAD/CAM zirconia, CAD/CAM glass fiber, cast titanium, and cast gold. A force of 100 N was applied to the crown, and the von Mises stresses were obtained. FEA revealed that the CAD/CAM zirconia post system produced the lowest maximum von Mises stress in the dentin layer at 115.8 MPa, while the CAD/CAM glass fiber post produced the highest stress in the dentin at 518.2 MPa. For a severely damaged anterior tooth, a zirconia post system is the best choice while a cast gold post ranks second. The CAD/CAM glass fiber post is least recommended in terms of stress level in the dentin.

  6. von Willebrand Factor and Oxidative Stress Parameters in Acute Coronary Syndromes

    Directory of Open Access Journals (Sweden)

    Zoran Koprivica

    2011-01-01

    Full Text Available Considering the role of von Willebrand factor (vWf in hemostasis, and the role of oxidative stress in the development of endothelial dysfunction and atherosclerotic disease, the aim of our study was to investigate the relationship between vWf, parameters of oxidative stress and different types of acute coronary syndromes (ACS. Levels of vWf activity (vWfAct, vWf antigen (vWfAg, nitric oxide (estimated through nitrites–NO2 −, superoxide anion radical (O2 −, hydrogen peroxide (H2O2, index of lipid peroxidation (estimated through thiobarbituric acid reactive substances–TBARS, superoxide dismutase (SOD and catalase (CAT activity of 115 patients were compared with those of 40 healthy controls. ACS patients had significantly higher vWfAct and vWfAg levels, as well as TBARS levels, while their levels of NO2 −, H2O2, SOD and CAT activities were lower than controls'. vWfAg showed high specificity and sensitivity as a test to reveal healthy or diseased subjects. Multivariant logistic regression marked only vWfAg and TBARS as parameters that were under independent effect of ACS type. The results of our study support the implementation of vWf in clinical rutine and into therapeutic targets, and suggest that ACS patients are in need of antioxidant supplementation to improve their impaired antioxidant defence.

  7. Effect of power history on the shape and the thermal stress of a large sapphire crystal during the Kyropoulos process

    Science.gov (United States)

    Nguyen, Tran Phu; Chuang, Hsiao-Tsun; Chen, Jyh-Chen; Hu, Chieh

    2018-02-01

    In this study, the effect of the power history on the shape of a sapphire crystal and the thermal stress during the Kyropoulos process are numerically investigated. The simulation results show that the thermal stress is strongly dependent on the power history. The thermal stress distributions in the crystal for all growth stages produced with different power histories are also studied. The results show that high von Mises stress regions are found close to the seed of the crystal, the highly curved crystal surface and the crystal-melt interface. The maximum thermal stress, which occurs at the crystal-melt interface, increases significantly in value as the crystal expands at the crown. After this, there is reduction in the maximum thermal stress as the crystal lengthens. There is a remarkable enhancement in the maximum von Mises stress when the crystal-melt interface is close to the bottom of the crucible. There are two obvious peaks in the maximum Von Mises stress, at the end of the crown stage and in the final stage, when cracking defects can form. To alleviate this problem, different power histories are considered in order to optimize the process to produce the lowest thermal stress in the crystal. The optimal power history is found to produce a significant reduction in the thermal stress in the crown stage.

  8. Influence of solder joint length to the mechanical aspect during the thermal stress analysis

    Science.gov (United States)

    Tan, J. S.; Khor, C. Y.; Rahim, Wan Mohd Faizal Wan Abd; Ishak, Muhammad Ikman; Rosli, M. U.; Jamalludin, Mohd Riduan; Zakaria, M. S.; Nawi, M. A. M.; Aziz, M. S. Abdul; Ani, F. Che

    2017-09-01

    Solder joint is an important interconnector in surface mount technology (SMT) assembly process. The real time stress, strain and displacement of the solder joint is difficult to observe and assess the experiment. To tackle these problems, simulation analysis was employed to study the von Mises stress, strain and displacement in the thermal stress analysis by using Finite element based software. In this study, a model of leadless electronic package was considered. The thermal stress analysis was performed to investigate the effect of the solder length to those mechanical aspects. The simulation results revealed that solder length gives significant effect to the maximum von Mises stress to the solder joint. Besides, changes in solder length also influence the displacement of the solder joint in the thermal environment. The increment of the solder length significantly reduces the von Mises stress and strain on the solder joint. Thus, the understanding of the physical parameter for solder joint is important for engineer prior to designing the solder joint of the electronic component.

  9. Stress-constrained topology optimization for compliant mechanism design

    DEFF Research Database (Denmark)

    de Leon, Daniel M.; Alexandersen, Joe; Jun, Jun S.

    2015-01-01

    This article presents an application of stress-constrained topology optimization to compliant mechanism design. An output displacement maximization formulation is used, together with the SIMP approach and a projection method to ensure convergence to nearly discrete designs. The maximum stress...... is approximated using a normalized version of the commonly-used p-norm of the effective von Mises stresses. The usual problems associated with topology optimization for compliant mechanism design: one-node and/or intermediate density hinges are alleviated by the stress constraint. However, it is also shown...

  10. Three-dimensional finite element analysis of the stress distribution pattern in a mandibular first molar tooth restored with five different restorative materials

    Directory of Open Access Journals (Sweden)

    Kathleen Manuela D'souza

    2017-01-01

    Conclusions: ICZ crown displayed the highest peak von Mises stress values under maximum and masticatory bite forces. ICZ and Lava crowns also allowed the least amount of stress distribution to the surrounding tooth structure, which is indicative of a favorable response of the underlying tooth structure to the overlying full-coverage indirect restorative material. These results suggest that ICZ and Lava crowns can be recommended for clinical use in cases of badly damaged teeth.

  11. Prevention: Stress corrosion. Insulation of freezing pipes of a GMP-multifunction plant at Degussa, Trostberg; Vorbeugung: Spannungsrisskorrosion. Daemmung von Kaelteleitungen einer GMP-Mehrfunktionsanlage bei Degussa, Trostberg

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    2003-08-29

    Stress corrosion can occure by halogeneous or strong alcalic solutions and by simultaneous influence of stress and moisture. The G+H Isolierung Muenchen uses the halogen free insulating material NH/Armaflex for the insulation of freezing pipelines, operating in the new GMP (Good Manufacturing Practice) plant at Trostberg. After the installation the insulated pipelines were layered by aluminium coatings. (GL) [German] Bei der Daemmung von Edelstahlleitungen besteht ein erhoehtes Risiko eines selektiven Korrosionsangriffs, z.B. in Form einer Spannungsrisskorrosion. Ausgeloest wird diese Korrosionsform durch halogenhaltige oder stark alkalische Loesungen und sie tritt beim gleichzeitigen Zusammenwirken von Zugspannungen und Feuchtigkeit auf. Fuer die Daemmung von Kaelteleitungen aus hochlegiertem Edelstahl einer neuen GMP (Good Manufacturing Practice)-Anlage am Standort Trostberg setzte G+H Isolierung Muenchen den halogenfreien Daemmstoff NH/Armaflex ein. Teilweise wurden die gedaemmten Leitungen anschliessend alukaschiert. (orig.)

  12. [Three-dimensional finite element analysis of stress distribution about abutments periodontal membranes of separated removable partial denture and conical telescope].

    Science.gov (United States)

    Tang, Ying; Wang, Min; Luo, Yun; Man, Yi

    2009-10-01

    To investigate and compare the stress of edentulous mucosa and periodontal membranes of the abutments under vertical loads for separated removable partial denture or conical telescope denture. One patient who had lost the second premolar and the first molar on the upper jaw and had I mobile abutments was chosen in the study. Two precise three dimensional finite element models were constructed by using screw CT image reconstruction technique and Materialise Mimics, Pro/Engineer WF 2.0, ANSYS Workbench software. Vertical forces were loaded on the two models. Then comparing and analyzing the von Mises stress distribution of the edentulous mucosa and the periodontal membranes of abutments between the separate removable partial denture and conical telescope denture in the software of ANSYS Workbench. The von Mises stress values of the edentulous mucosa of separate removable partial denture were larger than that of the conical telescope denture. The von Mises stress values of abutments periodontal membranes of separate removable partial denture were lower than that of conical telescope denture. Under vertical loads, compare with conical telescope denture, the separate removable partial denture can protect the abutments.

  13. Assessment of Creep Deformation, Damage, and Rupture Life of 304HCu Austenitic Stainless Steel Under Multiaxial State of Stress

    Science.gov (United States)

    Sahoo, K. C.; Goyal, Sunil; Parameswaran, P.; Ravi, S.; Laha, K.

    2018-01-01

    The role of the multiaxial state of stress on creep deformation and rupture behavior of 304HCu austenitic stainless steel was assessed by performing creep rupture tests on both smooth and notched specimens of the steel. The multiaxial state of stress was introduced by incorporating circumferential U-notches of different root radii ranging from 0.25 to 5.00 mm on the smooth specimens of the steel. Creep tests were carried out at 973 K over the stress range of 140 to 220 MPa. In the presence of notch, the creep rupture strength of the steel was found to increase with the associated decrease in rupture ductility. Over the investigated stress range and notch sharpness, the strengthening was found to increase drastically with notch sharpness and tended toward saturation. The fractographic studies revealed the mixed mode of failure consisting of transgranular dimples and intergranular creep cavitation for shallow notches, whereas the failure was predominantly intergranular for relatively sharper notches. Detailed finite element analysis of stress distribution across the notch throat plane on creep exposure was carried out to assess the creep failure of the material in the presence of notch. The reduction in von-Mises stress across the notch throat plane, which was greater for sharper notches, increased the creep rupture strength of the material. The variation in fracture behavior of the material in the presence of notch was elucidated based on the von-Mises, maximum principal, and hydrostatic stresses. Electron backscatter diffraction analysis of creep strain distribution across the notch revealed localized creep straining at the notch root for sharper notches. A master curve for predicting creep rupture life under the multiaxial state of stress was generated considering the representative stress having contributions from both the von-Mises and principal stress components of the stress field in the notch throat plane. Rupture ductility was also predicted based on the

  14. Mise en page et mise en texte avec les feuilles de style CSS

    OpenAIRE

    Buquet, Thierry

    2004-01-01

    http://lemo.irht.cnrs.fr/43/mo43-13.htm; International audience; Après dix ans d'histoire, les feuilles de style CSS s'imposent aujourd'hui comme un standard incontournable pour la mise en page et la mise en texte sur le web. Malgré un support parfois défectueux par les navigateurs web, leur utilisation apporte de nombreux avantages : séparation contenu / mise en forme, contrôle précis de la typographie se rapprochant des normes habituelles des publications scientifiques, mise en pages person...

  15. Weber and Mises: Views on Bureaucracy

    OpenAIRE

    Cosma Sorinel

    2013-01-01

    Bureaucracy is not a recent phenomenon. Its beginnings go a long way back in history. Looking into the issue of bureaucracy is a good starting point for the study of two social systems – capitalism and socialism. Such an analysis must be built onto the comparison between profit based management and bureaucratic management. Weber and Mises are two important names to mention when talking about bureaucracy. They both authored studies on bureaucracy, (Weber – Economy and Society in 1922, and Mise...

  16. Microstructural residual stress in particle-filled dental composite.

    Science.gov (United States)

    Prejzek, Ondřej; Spaniel, Miroslav; Mareš, Tomáš

    2015-01-01

    The main goal of this study is to develop a micromechanical model of a particle-filled dental composite focused on the residual stress (RS) field developed during the curing process in its microstructure. A finite element model of a representative volume element of filler and resin was developed, and volumetric shrinkage was simulated during the curing process. Four material models (von Mises plasticity model, Drucker-Prager plasticity model, von Mises plasticity model with stress relaxation and Drucker-Prager plasticity with stress relaxation) of the polymer resin were built to assess the influence of the material model on the resulting internal stress. The relationship between the curing process and the magnitude of the stress components will be described, and an analysis of the post-curing state of the material in particular microstructure locations will be conducted in this study. Obtained RS is comparable to the stresses developed in the material under the external load. The substantial dependence on the choice of material model for resin is to be observed, and the suitability of particular models is discussed.

  17. [Analysis of stress in periodontal ligament of the maxillary first molar on distal movement by nonlinear finite element method].

    Science.gov (United States)

    Dong, Jing; Zhang, Zhe-chen; Zhou, Guo-liang

    2015-06-01

    To analyze the stress distribution in periodontal ligament of maxillary first molar during distal movement with nonlinear finite element analysis, and to compare it with the result of linear finite element analysis, consequently to provide biomechanical evidence for clinical application. The 3-D finite element model including a maxillary first molar, periodontal ligament, alveolar bone, cancellous bone, cortical bone and a buccal tube was built up by using Mimics, Geomagic, ProE and Ansys Workbench. The material of periodontal ligament was set as nonlinear material and linear elastic material, respectively. Loads of different combinations were applied to simulate the clinical situation of distalizing the maxillary first molar. There were channels of low stress in peak distribution of Von Mises equivalent stress and compressive stress of periodontal ligament in nonlinear finite element model. The peak of Von Mises equivalent stress was lower when it was satisfied that Mt/F minus Mr/F approximately equals 2. The peak of compressive stress was lower when it was satisfied that Mt/F was approximately equal to Mr/F. The relative stress of periodontal ligament was higher and violent in linear finite element model and there were no channels of low stress in peak distribution. There are channels in which stress of periodontal ligament is lower. The condition of low stress should be satisfied by applied M/F during the course of distalizing the maxillary first molar.

  18. Hydrostatic Stress Effects in Metal Plasticity

    Science.gov (United States)

    Wilson, Christopher D.

    1999-01-01

    Since the 1940s, the theory of plasticity has assumed that hydrostatic stress does not affect the yield or postyield behavior of metals. This assumption is based on the early work of Bridgman. Bridgman found that hydrostatic pressure (compressive stress) does not affect yield behavior until a substantial amount of pressure (greater than 100 ksi) is present. The objective of this study was to determine the effect of hydrostatic tension on yield behavior. Two different specimen geometries were examined: an equal-arm bend specimen and a double edge notch specimen. The presence of a notch is sufficient to develop high enough hydrostatic tensile stresses to affect yield. The von Mises yield function, which does not have a hydrostatic component, and the Drucker-Prager yield function, which includes a hydrostatic component, were used in finite element analyses of the two specimen geometries. The analyses were compared to test data from IN 100 specimens. For both geometries, the analyses using the Drucker-Prager yield function more closely simulated the test data. The von Mises yield function lead to 5-10% overprediction of the force-displacement or force-strain response of the test specimens.

  19. Glacial isostatic stress shadowing by the Antarctic ice sheet

    Science.gov (United States)

    Ivins, E. R.; James, T. S.; Klemann, V.

    2005-01-01

    Numerous examples of fault slip that offset late Quaternary glacial deposits and bedrock polish support the idea that the glacial loading cycle causes earthquakes in the upper crust. A semianalytical scheme is presented for quantifying glacial and postglacial lithospheric fault reactivation using contemporary rock fracture prediction methods. It extends previous studies by considering differential Mogi-von Mises stresses, in addition to those resulting from a Coulomb analysis. The approach utilizes gravitational viscoelastodynamic theory and explores the relationships between ice mass history and regional seismicity and faulting in a segment of East Antarctica containing the great Antarctic Plate (Balleny Island) earthquake of 25 March 1998 (Mw 8.1). Predictions of the failure stress fields within the seismogenic crust are generated for differing assumptions about background stress orientation, mantle viscosity, lithospheric thickness, and possible late Holocene deglaciation for the D91 Antarctic ice sheet history. Similar stress fracture fields are predicted by Mogi-von Mises and Coulomb theory, thus validating previous rebound Coulomb analysis. A thick lithosphere, of the order of 150-240 km, augments stress shadowing by a late melting (middle-late Holocene) coastal East Antarctic ice complex and could cause present-day earthquakes many hundreds of kilometers seaward of the former Last Glacial Maximum grounding line.

  20. Three Dimensional Finite Element Analysis of Distal Abutment Stresses of Removable Partial Dentures with Different Retainer Designs

    Directory of Open Access Journals (Sweden)

    Simindokht Zarrati

    2015-11-01

    Full Text Available Objectives: This finite element method study aimed to compare the amount of stress on an isolated mandibular second premolar in two conventional reciprocal parallel interface designs of removable partial dentures (RPDs and the same RPD abutment tooth (not isolated.Materials and Methods: A Kennedy Class 1, modification 1 RPD framework was simulated on a 3D model of mandible with three different designs: an isolated tooth with a mesial rest, an isolated tooth with mesial and distal rests and an abutment with a mesial rest (which was not isolated; 26 N occlusal forces were exerted bilaterally on the first molar sites. Stress on the abutment teeth was analyzed using Cosmos Works 2009 Software.Results: In all designs, the abutment tooth stress concentration was located in the buccal alveolar crest. In the first model, the von Mises stress distribution in the contact area of I-bar clasp and cervical portion of the tooth was 19 MPa and the maximum stress was 30 MPa. In the second model, the maximum von Mises stress distribution was 15 MPa in the cervical of the tooth. In the third model, the maximum von Mises stress was located in the cervical of the tooth and the distal proximal plate.Conclusion: We recommend using both mesial and distal rests on the distal abutment teeth of distal extension RPDs. The abutment of an extension base RPD, which is not isolated in presence of its neighboring more anterior tooth, may have a better biomechanical prognosis.      

  1. Springback analysis in sheet metal forming by using the Ramberg-Osgood stress-strain relation

    Science.gov (United States)

    Lal, R. K.; Bhagat, M. K.; Dwivedi, J. P.; Singh, V. P.; Patel, S. K.

    2016-11-01

    The Ramberg-Osgood stress-strain relation is used to perform a theoretical springback analysis in the problem of bending of a narrow rectangular strip made of a strain-hardening material. The maximum strip thickness is 5 mm, and its length is significantly greater than the thickness. Based on the elasticity and plasticity deformation theory and also on the Tresca and von Mises yield criteria, an expression for the springback ratio is derived. The springback ratio depends on the ratio of the yield stress to Young's modulus, Poisson's ratio, strain hardening coefficient, and sheet thickness.

  2. Stressbelastung von Medizinstudierenden messen: Übersetzung des „Perceived Medical School Stress Instruments“ in die deutsche Sprache [Measurement of specific medical school stress: translation of the “Perceived Medical School Stress Instrument” to the German language

    Directory of Open Access Journals (Sweden)

    Voltmer, Edgar

    2013-05-01

    Burn-out. Vitaliano et al. haben bereits 1984 ein 13 Items umfassendes Instrument zur Messung der spezifischen Stressbelastung von Medizinstudierenden, das „Perceived Medical School Stress Instrument“ (PMSS, vorgestellt. Es wurde seitdem im englischsprachigen Bereich breit eingesetzt und validiert. Bislang liegt jedoch keine deutschsprachige Version des Instrumentes vor. Ziel des Projektes war die Übersetzung des PMSS in die deutsche Sprache, um es im Rahmen von Studien im deutschsprachigen Raum einzusetzen.Methodik: Die englischsprachigen Items des PMSS wurden von drei Untersuchern in die deutsche Sprache übersetzt. Die Versionen wurden synoptisch gegenübergestellt und auf dieser Basis wurde für jedes Item eine deutschsprachige Version formuliert. Diese Versionen wurden von Muttersprachlerinnen in die englische Sprache zurückübersetzt. Auf der Basis dieser Rückübersetzungen, eines kognitiven Debriefings an 19 deutschen Medizinstudierenden und einer testtheoretischen Evaluation an 169 deutschen Medizinstudierenden wurden dann die endgültigen deutschsprachigen Formulierungen festgelegt. Ergebnisse: Das PMSS konnte ohne größere Schwierigkeiten in die deutsche Sprache übersetzt werden. Sowohl zwischen den Übersetzungen in die deutsche Sprache als auch zwischen beiden Rückübersetzungen waren die Übereinstimmungen groß. Bei Diskrepanzen erfolgte die Einigung schnell und unkompliziert. Der Einsatz der deutschsprachigen Version erbrachte einen guten Wert für die Reliabilität (Cronbachs Alpha 0,81.Schlussfolgerung: Es steht nun auch für deutschsprachigen Raum ein spezifisches Instrument zur Messung der Stressbelastung von Medizinstudierenden zur Verfügung.

  3. Temperature and Thermal Stresses of Vehicles Gray Cast Brake

    Directory of Open Access Journals (Sweden)

    A. Belhocine

    2013-10-01

    Full Text Available The main purpose of this study is to analyze the thermomechanical behavior of the dry contact between the brake disc and pads during the braking phase. The simulation strategy is based on computer code ANSYS11. The modeling of transient temperature in the disc is actually used to identify the factor of geometric design of the disc to install the ventilation system in vehicles. The thermo-structural analysis is then used with coupling to determine the deformation established and the Von Mises stresses in the disc, the contact pressure distribution in pads. The results are satisfactory when compared to those found in previous studies.

  4. Residual stress simulation of circumferential welded joints

    Directory of Open Access Journals (Sweden)

    Melicher R.

    2007-11-01

    Full Text Available Residual stresses are an important consideration in the component integrity and life assessment of welded structure. The welding process is very complex time dependent physical phenomenon with material nonlinearity. The welding is a thermal process with convection between fluid flow and welding body, between welding bodyand environment. Next type of boundary conditions is radiation and thermo-mechanical contact on the outer surface of gas pipe in the near of weld. The temperature variation so obtained is utilised to find the distribution of the stress field.In this paper, a brief review of weld simulation and residual stress modelling using the finite element method (FEM by commercial software ANSYS is presented. Thermo-elastic-plastic formulations using a von Mises yield criterion with nonlinear kinematics hardening has been employed. Residual axial and hoop stresses obtained from the analysis have been shown. The commercial FEM code ANSYS was used for coupled thermalmechanical analysis.

  5. Stress analysis of different prosthesis materials in implant-supported fixed dental prosthesis using 3D finite element method

    Directory of Open Access Journals (Sweden)

    Pedram Iranmanesh

    2014-01-01

    Full Text Available Introduction: In the present study, the finite element method (FEM was used to investigate the effects of prosthesis material types on stress distribution of the bone surrounding implants and to evaluate stress distribution in three-unit implant-supported fixed dental prosthesis (FDP. Materials and Methods: A three-dimensional (3D finite element FDP model of the maxillary second premolar to the second molar was designed. Three load conditions were statically applied on the functional cusps in horizontal (57.0 N, vertical (200.0 N, and oblique (400.0 N, θ = 120° directions. Four standard framework materials were evaluated: Polymethyl methacrylate (PMMA, base-metal, porcelain fused to metal, andporcelain. Results: The maximum of von Mises stress in the oblique direction was higher than the vertical and horizontal directions in all conditions. In the bone-crestal section, the maximum von Mises stress (53.78 MPa was observed in PMMA within oblique load. In FDPs, the maximum stress was generated at the connector region in all conditions. Conclusion: A noticeable difference was not observed in the bone stress distribution pattern with different prosthetic materials. Although, higher stress value could be seen in polymethyl methacrylate, all types of prosthesis yielded the same stress distribution pattern in FDP. More clinical studies are needed to evaluate the survival rate of these materials.

  6. Impacts of environmental stress on genetic structures of forest tree stands as exemplified by European beech (Fagus sylvatica L.); Auswirkungen von Umweltbelastungen auf genetische Strukturen von Waldbestaenden am Beispiel der Buche (Fagus sylvatica L.)

    Energy Technology Data Exchange (ETDEWEB)

    Mueller-Starck, G. [Goettingen Univ. (Germany). Inst. fuer Forstgenetik und Forstpflanzenzuechtung, Forstliche Biometrie und Informatik

    1993-12-31

    Inheritance of isoenzymes in European beech was verified by means of analysis of segregations among full-sib families. 42 alleles were shown to be controlled genetically by a total of 17 polymorphic gene loci. In six adult stands, genetic structures between tolerant and sensitive subsets were compared (574 individuals). Furthermore, in order to study the dynamics of genetic variation, genetic structures were compared between germinating seeds (initial populations) and survivors at the age of two years under various field stress conditions (2986 individuals). The following tendencies are evident: (1) Genetic structures deviate significantly between tolerant and sensitive subsets in adult stands and between initial populations and juvenile survivors. (2) In adult stands, tolerant subsets reveal greater observed heterozygosities than sensitive subsets (surplus of 23.1%). (3) Among juvenile survivors, severe losses of genetic multiplicity can be expected (at least 17% of alleles). (4) Much greater gene pool diversity is indicated in tolerant subsets as compared to sensitive ones (trends to greater evenness of frequency distributions). (5) In the expression of viability characters, additive allelic effects are suggested in adult stands, but the genetic background is complex in heterogeneous environments. (6) In juvenile survivors, genetic selection is clearly indicated. Environmental stress affects genetic structures of beech populations in many different ways. It is concluded that long term exposure to complex field stress results in a viability advantage for genetically diverse populations and individuals. In juvenile stages, certain alleles may account for superior viabilities, but this phenomenon does not seem to hold for succeeding life stages. In such environments, genetically heterogeneous populations are strongly suggested. (orig./UWa) [Deutsch] Ziel der Untersuchungen war die Ueberpruefung genetischer Auswirkungen von Umweltstress auf Altbestaende und

  7. Three-dimensional finite element analysis of the stress distribution pattern in a mandibular first molar tooth restored with five different restorative materials.

    Science.gov (United States)

    D'souza, Kathleen Manuela; Aras, Meena Ajay

    2017-01-01

    Badly broken or structurally compromised posterior teeth are frequently associated with crown/root fracture. Numerous restorative materials have been used to fabricate indirect full-coverage restorations for such teeth. This study aims to evaluate and compare the effect of restorative materials on the stress distribution pattern in a mandibular first molar tooth, under varying loading conditions and to compare the stress distribution pattern in five commonly used indirect restorative materials. Five three-dimensional finite element models representing a mandibular first molar tooth restored with crowns of gold, porcelain fused to metal, composite (Artglass), alumina-based zirconia (In-Ceram Zirconia [ICZ]), and double-layered zirconia-based materials (zirconia core veneered with porcelain, Lava) were constructed, using a Finite Element Analysis Software (ANSYS version 10; ANSYS Inc., Canonsburg, PA, USA). Two loading conditions were applied, simulating maximum bite force of 600 N axially and normal masticatory bite force of 225 N axially and nonaxially. Both all-ceramic crowns allowed the least amount of stress distribution to the surrounding tooth structure. In maximum bite force-simulation test, alumina-based all-ceramic crown displayed the highest von Mises stresses (123.745 MPa). In the masticatory bite force-simulation test, both all-ceramic crowns (122.503-133.13 MPa) displayed the highest von Mises stresses. ICZ crown displayed the highest peak von Mises stress values under maximum and masticatory bite forces. ICZ and Lava crowns also allowed the least amount of stress distribution to the surrounding tooth structure, which is indicative of a favorable response of the underlying tooth structure to the overlying full-coverage indirect restorative material. These results suggest that ICZ and Lava crowns can be recommended for clinical use in cases of badly damaged teeth.

  8. A finite element investigation of quasi-static and dynamic asymptotic crack-tip fields in hardening elastic-plastic solids under plane stress. II - Crack growth in power-law hardening materials

    Science.gov (United States)

    Deng, Xiaomin; Rosakis, Ares J.

    1992-11-01

    Quasi-static and dynamic crack growth under mode I plane stress, steady state, and small-scale yielding conditions was investigated for power-law hardening elastic-plastic materials which are homogenous and isotropic and obey the von Mises yield criterion and the associated flow rule. The effective stress-strain curve of the materials is assumed to follow the Ramberg-Osgood-type power law effective stress-strain curve. The results show many similarities with those found by Deng and Rosakis (1992) for linear hardening solids, except that, in case of power-law hardening materials, the plastic strain singularities at the crack tip are of logarithmic type.

  9. Finite element stress analysis of stainless steel crowns.

    Science.gov (United States)

    Prabhakar, Attiguppe R; Yavagal, Chandrashekar M; Chakraborty, Amrita; Sugandhan, S

    2015-01-01

    Though stainless steel crowns (SSCs) have often been stated as the best restorative modality, there are limited studies demonstrating its efficacy in restoring the functional integrity of the primary dentition. Hence has arisen, the necessity to establish the supremacy of SSCs. Evaluation of the efficacy of SSC to with stand compressive (0°), shearing (90°), and torsional (45°) stress when used as a restorative material. The study design employed four finite element models, each with differing amounts of tooth structure, which were exported to ANSYS software and subjected to an average simulated bite force of 245N. Four maxillary deciduous primary molars restored with SSCs (3M ESPE) were subjected to spiral computed tomography (CT) in order to obtain three-dimensional (3D) images, which were then converted into finite element models. They were each subjected to forces along the long axis of the tooth and at 45°and 90°. The maximal equivalent von Mises stress was demonstrated in the SSCs of all the models with only a minimal amount observed in the underlying dentine. In all situations, the maximal equivalent von Mises stress was well below the ultimate tensile strength values of stainless steel and dentine. Even at maximal physiologic masticatory force levels, a grossly destructed tooth restored with SSC is able to resist deformation.

  10. Finite Element Stress Analysis of Stainless Steel Crowns

    Directory of Open Access Journals (Sweden)

    Attiguppe R Prabhakar

    2015-01-01

    Full Text Available Background: Though stainless steel crowns (SSCs have often been stated as the best restorative modality, there are limited studies demonstrating its efficacy in restoring the functional integrity of the primary dentition. Hence has arisen, the necessity to establish the supremacy of SSCs. Aim: Evaluation of the efficacy of SSC to with stand compressive (0°, shearing (90°, and torsional (45° stress when used as a restorative material. Settings and Design: The study design employed four finite element models, each with differing amounts of tooth structure, which were exported to ANSYS software and subjected to an average simulated bite force of 245N. Materials and Methods: Four maxillary deciduous primary molars restored with SSCs (3M ESPE were subjected to spiral computed tomography (CT in order to obtain three-dimensional (3D images, which were then converted into finite element models. They were each subjected to forces along the long axis of the tooth and at 45°and 90°. Results: The maximal equivalent von Mises stress was demonstrated in the SSCs of all the models with only a minimal amount observed in the underlying dentine. In all situations, the maximal equivalent von Mises stress was well below the ultimate tensile strength values of stainless steel and dentine. Conclusion: Even at maximal physiologic masticatory force levels, a grossly destructed tooth restored with SSC is able to resist deformation.

  11. Ferrule Designs and Stress Distribution in Endodontically Treated Upper Central Incisors: 3D Finite Element Analysis

    Directory of Open Access Journals (Sweden)

    A. Hassan Ahangari

    2008-09-01

    Full Text Available Objective: The main goal of this study was to evaluate stress distribution of endodonti-cally treated maxillary central incisors restored with glass fiber posts, composite resin cores, and crowns with different ferrule designs.Materials and Methods: Four three-dimensional models of a maxillary central incisor were modeled in SolidWorks 2006. Tooth with no ferrule, tooth with a 2 mm circumferen-tial ferrule, tooth with a 2 mm beveled ferrule and tooth with a 0.5 mm circumferential ferrule. The teeth were restored with glass fiber posts, composite resin cores, and full ce-ramics crowns. Each model was loaded (1 N on the palatal side at an angle of 45 degrees to tooth long axis. Von Mises stress findings along the inner surface of the root canals were assessed and compared.Results: The Von Mises Stress at CEJ was the highest in the model without a ferrule when compared to the other models (without ferrule 0.0696, short ferrule 0.0492, cylindrical fer-rule 0.0248, and beveled ferrule 0.0387 MPa.Conclusion: Endodontically treated maxillary central incisors with a ferrule length vary-ing between 0.5 mm and 2.0 mm exhibit lower stress distribution compared to those with-out a ferrule. Keeping a long ferrule is suggested to decrease the stress at the cervical area of restored teeth.

  12. ANSYS Modeling of Hydrostatic Stress Effects

    Science.gov (United States)

    Allen, Phillip A.

    1999-01-01

    Classical metal plasticity theory assumes that hydrostatic pressure has no effect on the yield and postyield behavior of metals. Plasticity textbooks, from the earliest to the most modem, infer that there is no hydrostatic effect on the yielding of metals, and even modem finite element programs direct the user to assume the same. The object of this study is to use the von Mises and Drucker-Prager failure theory constitutive models in the finite element program ANSYS to see how well they model conditions of varying hydrostatic pressure. Data is presented for notched round bar (NRB) and "L" shaped tensile specimens. Similar results from finite element models in ABAQUS are shown for comparison. It is shown that when dealing with geometries having a high hydrostatic stress influence, constitutive models that have a functional dependence on hydrostatic stress are more accurate in predicting material behavior than those that are independent of hydrostatic stress.

  13. Influence of three different implant thread designs on stress distribution: A three-dimensional finite element analysis

    Directory of Open Access Journals (Sweden)

    Mansi Manish Oswal

    2016-01-01

    Full Text Available Purpose: Clinical success of implant prosthodontics is dependent in part upon the type of implant thread design. The selection of implant thread design plays an important role in the outcome of the treatment. This study was undertaken to evaluate the pattern of stress distribution using a finite element analysis; hence, the area which would be bearing maximum load for a given design would be arrived. Materials and Methods: Three implants with different thread designs, namely V-thread, buttress, and reverse buttress thread designs were considered and dimensions were standardized. The site considered was the mandibular molar region with cortical and trabecular bone assuming to be isotropic and homogeneous. The implant modeling was done with the CATIA software. Vertical loads of 100N were applied. The stresses were calculated as Von Mises stress criterion. Results: Maximum stresses were seen at the cortical bone and were transferred to the implant. Minimum Von Mises stresses were seen with reverse buttress thread design at the cortical bone. The stresses were observed least at the cancellous bone and maximum at the implant. Conclusion: Hence, within the limitations of this study the results obtained can be applied clinically for appropriate selection of implant thread design for a predictable success of implant therapy.

  14. Stress Distribution in Roots Restored with Fiber Posts and An Experimental Dentin Post: 3D-FEA.

    Science.gov (United States)

    Diana, Hugo Henrique; Oliveira, Juliana Santos; Ferro, Mariana Carolina de Lara; Silva-Sousa, Yara T Corrêa; Gomes, Érica Alves

    2016-01-01

    The aim of this study was to compare the stress distribution in radicular dentin of a maxillary canine restored with either a glass fiber post, carbon fiber post or an experimental dentin post using finite element analysis (3D-FEA). Three 3D virtual models of a maxillary canine restored with a metal-ceramic crown and glass fiber post (GFP), carbon fiber post (CFP), and experimental dentin post (DP) were obtained based on micro-CT images. A total of 180 N was applied on the lingual surface of the incisal third of each tooth at 45 degrees. The models were supported by the periodontal ligament fixed in three axes (x=y=z=0). The von Mises stress (VMS) of radicular dentin and the intracanal posts was calculated. The structures of all groups showed similar values (MPa) and distribution of maximum von Mises stress. Higher stress was found in the apical third of dentin while the posts presented homogeneous stress distribution along the axis. The fiber and dentin posts exhibited similar stress values and distribution. Thus, the experimental dentin post is a promising restorative material.

  15. Optimization of custom cementless stem using finite element analysis and elastic modulus distribution for reducing stress-shielding effect.

    Science.gov (United States)

    Saravana Kumar, Gurunathan; George, Subin Philip

    2017-02-01

    This work proposes a methodology involving stiffness optimization for subject-specific cementless hip implant design based on finite element analysis for reducing stress-shielding effect. To assess the change in the stress-strain state of the femur and the resulting stress-shielding effect due to insertion of the implant, a finite element analysis of the resected femur with implant assembly is carried out for a clinically relevant loading condition. Selecting the von Mises stress as the criterion for discriminating regions for elastic modulus difference, a stiffness minimization method was employed by varying the elastic modulus distribution in custom implant stem. The stiffness minimization problem is formulated as material distribution problem without explicitly penalizing partial volume elements. This formulation enables designs that could be fabricated using additive manufacturing to make porous implant with varying levels of porosity. Stress-shielding effect, measured as difference between the von Mises stress in the intact and implanted femur, decreased as the elastic modulus distribution is optimized.

  16. Laser circular cutting of Kevlar sheets: Analysis of thermal stress filed and assessment of cutting geometry

    Science.gov (United States)

    Yilbas, B. S.; Akhtar, S. S.; Karatas, C.

    2017-11-01

    A Kevlar laminate has negative thermal expansion coefficient, which makes it difficult to machine at room temperaures using the conventional cutting tools. Contararily, laser machining of a Kevlar laminate provides advantages over the conventional methods because of the non-mechanical contact between the cutting tool and the workpiece. In the present study, laser circular cutting of Kevlar laminate is considered. The experiment is carried out to examine and evaluate the cutting sections. Temperature and stress fields formed in the cutting section are simulated in line with the experimental study. The influence of hole diameters on temperature and stress fields are investigated incorporating two different hole diameters. It is found that the Kevlar laminate cutting section is free from large size asperities such as large scale sideways burnings and attachemnt of charred residues. The maximum temperature along the cutting circumference remains higher for the large diameter hole than that of the small diameter hole. Temperature decay is sharp around the cutting section in the region where the cutting terminates. This, in turn, results in high temperature gradients and the thermal strain in the cutting region. von Mises stress remains high in the region where temperature gradients are high. von Mises stress follows similar to the trend of temperature decay around the cutting edges.

  17. Stress Distribution in Splinted and Unsplinted Implant-Supported Maxillary Overdentures: A 3D Finite Element Analysis.

    Science.gov (United States)

    Geramy, Allahyar; Habibzadeh, Sareh

    2018-02-01

    This study was accomplished to assess the biomechanical state of splinting in implant-supported maxillary overdentures. Two models of maxillary overdentures were designed in SolidWorks 2011. The first model included 4 separate implants and ball abutments, whereas the second one included 4 splinted implants connected with a bar. Evaluation was performed in ANSYS Workbench software with 200 N load applied at the molar-premolar region, bilaterally. The maximum equivalent stress and strain (von Mises) was recorded and analyzed along a path between the implants in the crestal bone and the prosthetic attachments. First model presented higher values of strain in prosthetic attachment and higher values of von Mises stress in crestal bone. The second model presented higher stress concentration in the gingival tissue of premolar area (near the bar), whereas the peak stress values were reported within the most distal part of the soft tissue support of the prosthesis in the first model (unsplinted). Splinting maxillary overdentures implants is associated with significant lower stress levels in the surrounding bone tissue.

  18. The effect of implant and abutment diameter on peri-implant bone stress: A three-dimensional finite element analysis

    Directory of Open Access Journals (Sweden)

    Helen Mary Abraham

    2016-01-01

    Full Text Available Introduction: Load transfer mechanisms from the implant to surrounding bone and failure of osseointegrated implants are affected by implant geometry and mechanical properties of the site of placement as well as crestal bone resorption. Estimation of such effects allows for a correct design of implant geometry to minimize crestal bone loss and implant failure. Objectives: To evaluate the effect of implant and abutment diameter on stress distribution in the peri-implant area. Materials and Methods: Three-dimensional finite element models created to replicate completely osseointegrated endosseous titanium implants and were used for the purpose of stress analysis. Two study groups that consisting of a regular platform (RP group and narrow platform (NP group were used with a standard bone density and loaded using the ANSYS Workbench software to calculate the von Mises and Principal (maximum tensile and minimum compressive stress. Results: The von Mises, compressive, and tensile stresses in the peri-implant bone were lower in the RP model compared to the NP model. Conclusion: RP model yielded a positive result with regard to lowering of peri-implant bone stress levels, in healthy as well as compromised bone qualities when compared to NP designs.

  19. Examination of cracks and fractures on operationally stressed turbine blades; Untersuchung von Rissen und Bruechen an betriebsbeanspruchten Turbinenschaufeln

    Energy Technology Data Exchange (ETDEWEB)

    Vodopivec, F. [Inst. of Metals and Technologies, Ljubljana (Slovenia); Vrbic, V.S. [Electric Power Work Nikola Tesla, Obrenovac (Yugoslavia); Ule, B. [Inst. of Metals and Technologies, Ljubljana (Slovenia); Zvokelj, J. [Inst. of Metals and Technologies, Ljubljana (Slovenia); Vehovar, L. [Inst. of Metals and Technologies, Ljubljana (Slovenia)

    1997-04-01

    This paper summarises the results of mechanical and fractographic examinations which had been carried out on fractures on the low-pressure blades of a 300 MW steam turbine. The crack-affected turbine blades had been removed, partly during inspections and partly after turbine breakdowns, in contrast to the fractured blades which had been extracted without exception following turbine breakdowns. (orig.) [Deutsch] Im vorliegenden Beitrag werden die Ergebnisse der mechanischen und fraktographischen Untersuchungen zusammengefasst, die an Bruechen von ND-Schaufeln einer 300-MW-Dampfturbine durchgefuehrt wurden. Die rissbehafteten Turbinenschaufeln wurden teilweise waehrend Revisionen und teilweise nach Turbinenversagen entnommen, im Gegensatz zu den gebrochenen Schaufeln, die ausnahmslos nach Turbinenausfall ausgebaut wurden. (orig.)

  20. Virtual analysis of stresses in human teeth restored with esthetic posts

    Directory of Open Access Journals (Sweden)

    Martha Vasconcellos Amarante

    2008-12-01

    Full Text Available The use of intra-radicular posts for rebuilding of damaged teeth is a normal practice in contemporary dentistry. However, dental roots restored with posts are subjected to the risk of failure under occlusal loads, particularly in cases of small dentin thickness. This study adopted the finite element analysis to compare the elastic stress distribution in simulated endodontically treated maxillary central incisor restored with two different esthetic posts, a ceramic post and a prefabricated fiber glass post. Under masticatory load, the shear stress and von Mises equivalent stress were determined for the different regions of the two models. The results demonstrated that stress concentrations occurred mainly in the cervical dentin in the prefabricated fiber glass post model. The ceramic post model presented stress concentration in a region limited to the proper post adjacent to its apical end, thus preserving the root dentin.

  1. Analysis of stress in bone and microimplants during en-masse retraction of maxillary and mandibular anterior teeth with different insertion angulations: a 3-dimensional finite element analysis study.

    Science.gov (United States)

    Jasmine, M Issa Fathima; Yezdani, A Arif; Tajir, Faisal; Venu, R Murali

    2012-01-01

    The proper angle of microimplant insertion is important for cortical anchorage, patient safety, and biomechanical control. However, the actual impact of different insertion angulations on stability is unknown. To perform 3-dimensional finite element analysis, finite element models of a maxilla and a mandible with types D3 and D2 bone quality, and of microimplants with a diameter of 1.3 mm and lengths of 8 and 7 mm were generated. The microimplants were inserted at 30°, 45°, 60°, and 90° to the bone surface. A simulated horizontal orthodontic force of 200 g was applied to the center of the microimplant head, and stress distribution and its magnitude were analyzed with a 3-dimensional finite element analysis program. The maximum von Mises stresses in the microimplant and the cortical bone decreased as the insertion angle increased. Analysis of the stress distribution in the cortical and cancellous bones showed that the stress was absorbed mostly in the cortical bone, and little was transmitted to the cancellous bone. The maximum von Mises stress was higher in type D3 bone quality than type D2 bone quality. Placement of microimplants at a 90° angulation in the bone reduces the stress concentration, thereby increasing the likelihood of implant stabilization. Perpendicular insertion offers more stability to orthodontic loading. Copyright © 2012 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

  2. Inhibition of ADAMTS-13 by Doxycycline Reduces von Willebrand Factor Degradation During Supraphysiological Shear Stress: Therapeutic Implications for Left Ventricular Assist Device-Associated Bleeding.

    Science.gov (United States)

    Bartoli, Carlo R; Kang, Jooeun; Restle, David J; Zhang, David M; Shabahang, Cameron; Acker, Michael A; Atluri, Pavan

    2015-11-01

    The aim of this study was to investigate a potential therapy for left ventricular assist device (LVAD)-associated bleeding. Nonsurgical bleeding is the most frequent complication of LVAD support. Recent evidence has demonstrated that supraphysiological shear stress from continuous-flow LVADs accelerates von Willebrand factor (vWF) metabolism by the action of a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13 (ADAMTS-13) (the vWF protease). An acquired vWF deficiency causes bleeding. This suggests that ADAMTS-13 is a clinical target to reduce vWF degradation. We tested the hypothesis that inhibition of ADAMTS-13 with doxycycline, an inexpensive, clinically approved drug, reduces vWF degradation during shear stress. Whole blood was collected from human donors (n = 15), and purified, recombinant ADAMTS-13 protein was obtained. An enzyme-linked immunosorbent assay (ELISA) was used to quantify the dose relationship between doxycycline and ADAMTS-13 activity prior to shear stress (n = 10). To determine the effect of shear stress, plasma and recombinant ADAMTS-13 were exposed to LVAD-like supraphysiological shear stress (approximately 175 dyne/cm(2)). vWF multimers and degradation fragments were characterized with electrophoresis and immunoblotting (n = 10). Förster resonance energy transfer was used to quantify plasma ADAMTS-13 activity (n = 10). An ELISA was used to quantify vWF:collagen binding activity. Platelet aggregometry was performed with adenosine 5'-diphosphate, collagen, and ristocetin (vWF-platelet pathway) agonism (n = 10). Doxycycline significantly decreased plasma ADAMTS-13 activity (p = 0.01) and the activity of recombinant human ADAMTS-13 protein by 21%. After plasma was exposed to shear stress, the same pattern of vWF degradation was observed as previously reported for LVAD patients, and vWF:collagen binding activity decreased significantly (p = 0.002). Doxycycline significantly decreased ADAMTS-13 activity (p = 0.04) and

  3. Disease specific stress of tumor patients at the beginning of radiotherapy. Effect on psychosocial support requirement; Krankheitsspezifische Belastungen von Tumorpatienten zu Beginn einer Strahlentherapie. Auswirkungen auf den psychosozialen Betreuungsbedarf

    Energy Technology Data Exchange (ETDEWEB)

    Sehlen, S.; Hollenhorst, H.; Schymura, B.; Firsching, M.; Duehmke, E. [Ludwig-Maximilians-Univ., Muenchen (Germany). Klinik und Poliklinik fuer Strahlentherapie und Radioonkologie; Aydemir, U. [Inst. fuer Biometrie und Epidemiologie, Klinikum Grosshadern, Ludwig-Maximilians-Univ., Muenchen (Germany); Herschbach, P. [Technische Univ. Muenchen (Germany). Inst. und Poliklinik fuer Psychosomatische Medizin, Psychotherapie und medizinische Psychologie

    2001-10-01

    Purpose: Radiotherapy brings a tumor patient into a special life situation in which different variables play a role of often unknown importance. The goal of this study was to investigate disease specific stress of tumor patients at the beginning of radiotherapy with established psychodiagnostic questionnaires and to evaluate the effect on psychosocial support requirement in order to reduce stress and to improve quality of life and compliance during radiotherapeutical treatment. Patients and Methods: 732 patients were screened, of whom 446 (60.9%) fulfilled the criteria for inclusion (refusals 21.0%, low Karnofsky performance status 6.6%, management problems 3.4%, language barriers 3.0%, cognitive restrictions 2.6%, death 2.5%). Disease specific aspects of stress in the questionnaire (Fragebogen zur Belastung von Krebspatienten, FBK), life situation (LS) and self-defined care requirements (BB) were self-rated by patients with different tumor types before radiotherapy. Medical and sociodemographic data were also documented. We investigated 446 patients (262 male, 184 female; median age 60.0 years) with different diagnoses. Results: Stress was observed mainly due to reduction of efficiency, anxiety and pain on the subscales. Women had a significant higher stress on subscales of pain (p=0.016) and anxiety (p=0.009), patients younger than 45 years in the subscale information (p=0.002) and patients older than 45 and younger than 60 years in the subscale anxiety (p=0.002) and the total score (p=0.003). Patients with mamma carcinoma had the highest stress. The maximum percentages of patients under high stress were found for the subscales of efficiency (43%) and anxiety (40%). The support requirement was characterized by the need of more medical information and dialogue with the doctor. We saw a significant correlation of high stress and high care requirement. Conclusions: Psychosocial support should be founded on psychosocial stress diagnostic and self-defined care

  4. Stress Distribution on Short Implants at Maxillary Posterior Alveolar Bone Model With Different Bone-to-Implant Contact Ratio: Finite Element Analysis.

    Science.gov (United States)

    Yazicioglu, Duygu; Bayram, Burak; Oguz, Yener; Cinar, Duygu; Uckan, Sina

    2016-02-01

    The aim of this study was to evaluate the stress distribution of the short dental implants and bone-to-implant contact ratios in the posterior maxilla using 3-dimensional (3D) finite element models. Two different 3D maxillary posterior bone segments were modeled. Group 1 was composed of a bone segment consisting of cortical bone and type IV cancellous bone with 100% bone-to-implant contact. Group 2 was composed of a bone segment consisting of cortical bone and type IV cancellous bone including spherical bone design and homogenous tubular hollow spaced structures with 30% spherical porosities and 70% bone-to-implant contact ratio. Four-millimeter-diameter and 5-mm-height dental implants were assumed to be osseointegrated and placed at the center of the segments. Lateral occlusal bite force (300 N) was applied at a 25° inclination to the implants long axis. The maximum von Mises stresses in cortical and cancellous bones and implant-abutment complex were calculated. The von Mises stress values on the implants and the cancellous bone around the implants of the 70% bone-to-implant contact group were almost 3 times higher compared with the values of the 100% bone-to-implant contact group. For clinical reality, use of the 70% model for finite element analysis simulation of the posterior maxilla region better represents real alveolar bone and the increased stress and strain distributions evaluated on the cortical and cancellous bone around the dental implants.

  5. Influence of PEEK Coating on Hip Implant Stress Shielding: A Finite Element Analysis

    Directory of Open Access Journals (Sweden)

    Jesica Anguiano-Sanchez

    2016-01-01

    Full Text Available Stress shielding is a well-known failure factor in hip implants. This work proposes a design concept for hip implants, using a combination of metallic stem with a polymer coating (polyether ether ketone (PEEK. The proposed design concept is simulated using titanium alloy stems and PEEK coatings with thicknesses varying from 100 to 400 μm. The Finite Element analysis of the cancellous bone surrounding the implant shows promising results. The effective von Mises stress increases between 81 and 92% for the complete volume of cancellous bone. When focusing on the proximal zone of the implant, the increased stress transmission to the cancellous bone reaches between 47 and 60%. This increment in load transferred to the bone can influence mineral bone loss due to stress shielding, minimizing such effect, and thus prolonging implant lifespan.

  6. Damage from light and antioxidative protective mechanisms in plants exposed to various stresses including traffic exhaust gases. Final report; Lichtschaeden und antioxidative Schutzeinrichtungen in Pflanzen bei Einwirkung von Stressfaktoren und Automobilabgasen. Schlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Feierabend, J.

    1992-12-31

    In intact leaves the catalose enzyme is photinactivated and degraded. Similarly to the D1 protein of photosystem II (PSII) it therefore has a high turnover in a bright environment and must continually be resynthesised. Mildly oxidative conditions induce greater catalase activity. With growing stress (cold, heat, salt, osmotic stress, senescence) there is a gradual shift of the steady state equilibrium due to enhanced photodegradation and inhibition of repair mechanisms. A rapid drop`n catalase concentration and photoinhibition of PSII are therefore early indicators of first photooxidative damage. The stress caused by experimental, realistic, doses of automobile exhaust gases and ozone was not so severe as to induce photoinhibition of catalase or PSII but merely led to a slight increase in antioxidative enzymes. The concentrations and redox equilibria of antioxidatives was not significantly affected. Exposition to these air pollutants in combination with cold and light had a far stronger effect on light-sensitive cumber leaves in the recovery phase than without additional stressors. (orig.) [Deutsch] Das Enzym Katalase wird in intakten Blaettern photoinaktiviert und abgebaut. Daher weist es wie das D1-Protein des Photosystems II (PSII) im Licht einen schnellen Turnover auf und muss staendig durch Neusynthese ersetzt werden. Milde oxidative Bedingungen induzieren eine hoehere Katalaseaktivitaet. Unter staerkeren Stressbelastungen (Kaelte, Hitze, Salz, osmotischer Stress, Schwermetalle, Seneszenz) verschiebt sich durch verstaerkte Photodegradation oder Behinderung der Reparatur das Gleichgewicht des Turnovers, und ein schneller apparenter Katalaseverlust und die Photoinhibition von PSII sind fruehe Indikatoren beginnender photooxidativer Schaeden. Belastungen mit realistischen Dosen von Automobilabgasen und Ozon waren nicht so gravierend, dass sie die Photoinhibition von Katalase oder PSII ausloesten, sondern sie induzierten teils eine leichte Erhoehung antioxidativer

  7. The Old Neo-Liberalism. The Neo-Liberalist Germ in Mises' and Hayek's Theories

    Directory of Open Access Journals (Sweden)

    Vanessa Lamattina

    2016-09-01

    Full Text Available What is neo-liberalism? I’m going to affirm here that, as well as being a political doctrine born in the 1970s, neo-liberalism is the construction, the extension and the final reinforcement of a number of classical elements. My argument is that many of the typical aspects of contemporary neo-liberalism were already present in theories expressed by thinkers such as L. von Mises and F. A. von Hayek. As proof of this fact, I reclaim some characteristics of the present neo-liberal phenomenon as having been conceived by the above authors. These characteristics actually imply the ongoing spread of a dominant ideology that tends to pit the concept of liberty against those of rationality and critical consciousness. First, the article will analyse the changes that have occurred within the phenomenon of consumerism, which becomes en-twined with the competitive and entrepreneurial spirit of the individual; second, it will reflect on the wide-spread aversion to socialist policies, and in fact to all policies that provide for public intervention by the State and that change the relationship between State and economy; finally, it will relate these investiga-tions to the ideological and structural model that supports the European Union.

  8. A finite element analysis of two different dental implants: stress distribution in the prosthesis, abutment, implant, and supporting bone.

    Science.gov (United States)

    Quaresma, Sergio E T; Cury, Patricia R; Sendyk, Wilson R; Sendyk, Claudio

    2008-01-01

    This study evaluates the influence of 2 commercially available dental implant systems on stress distribution in the prosthesis, abutment, implant, and supporting alveolar bone under simulated occlusal forces, employing a finite element analysis. The implants and abutments evaluated consisted of a stepped cylinder implant connected to a screw-retained, internal, hexagonal abutment (system 1) and a conical implant connected to a solid, internal, conical abutment (system 2). A porcelain-covered, silver-palladium alloy was used as a crown. In each case, a simulated, 100-N vertical load was applied to the buccal cusp. A finite element model was created based on the physical properties of each component, and the values of the von Mises stresses generated in the prosthesis, abutment, implant, and supporting alveolar bone were calculated. In the prostheses, the maximum von Mises stresses were concentrated at the points of load application in both systems, and they were greater in system 1 (148 N/mm2) than in system 2 (55 N/mm2). Stress was greater on the abutment of system 2 than of system 1 on both the buccal (342 N/mm2 x 294 N/mm2) and lingual (294 N/mm2 x 148 N/ mm2) faces. Stress in the cortical, alveolar bone crest was greater in system 1 than in system 2 (buccal: 99.5 N/mm2 x 55 N/mm2, lingual: 55 N/mm2 x 24.5 N/mm2, respectively). Within the limits of this investigation, the stepped cylinder implant connected to a screw-retained, internal hexagonal abutment produces greater stresses on the alveolar bone and prosthesis and lower stresses on the abutment complex. In contrast, the conical implant connected to a solid, internal, conical abutment furnishes lower stresses on the alveolar bone and prosthesis and greater stresses on the abutment.

  9. Fracture resistance and analysis of stress distribution of implant-supported single zirconium ceramic coping combination with abutments made of different materials.

    Science.gov (United States)

    Firidinoğlu, Kadir; Toksavul, Suna; Toman, Muhittin; Sarikanat, Mehmet; Nergiz, Ibrahim

    2012-08-01

    The purpose of this study was to compare the fracture resistance and fracture mode of single implant-zirconium coping combinations using zirconium and titanium abutments and to analyze the stress distribution pattern using three-dimensional finite elements analysis. Twenty implants with titanium and zirconium abutments were randomly divided into two groups (n = 10) and into resin blocks. Zirconium copings were cemented onto the abutments. The specimens were loaded with 135° angles to the long axis and the load values at the moment of failure were recorded using a universal test machine. Stress levels were calculated according to the maximum Von Mises criteria. The fracture resistances for titanium and zirconium abutment groups were 525.65 N and 514.05 N, respectively. No significant differences were observed between two groups regarding the fracture resistance levels. The maximum Von Mises equivalent stress concentrated on zirconium copings in both of the groups. Implant-abutment-ZrO2 coping combination has the potential to withstand physiological occlusal forces in the anterior region. Three-dimensional finite elements analysis results of the implant-abutment-ZrO2 coping combination is compatible with the results of fracture resistance.

  10. Stress Analysis of Osteoporotic Lumbar Vertebra Using Finite Element Model with Microscaled Beam-Shell Trabecular-Cortical Structure

    Directory of Open Access Journals (Sweden)

    Yoon Hyuk Kim

    2013-01-01

    Full Text Available Osteoporosis is a disease in which low bone mass and microarchitectural deterioration of bone tissue lead to enhanced bone fragility and susceptibility to fracture. Due to the complex anatomy of the vertebral body, the difficulties associated with obtaining bones for in vitro experiments, and the limitations on the control of the experimental parameters, finite element models have been developed to analyze the biomechanical properties of the vertebral body. We developed finite element models of the L2 vertebra, which consisted of the endplates, the trabecular lattice, and the cortical shell, for three age-related grades (young, middle, and old of osteoporosis. The compressive strength and stiffness results revealed that we had developed a valid model that was consistent with the results of previous experimental and computational studies. The von-Mises stress, which was assumed to predict the risk of a burst fracture, was also determined for the three age groups. The results showed that the von-Mises stress was substantially higher under relatively high levels of compressive loading, which suggests that patients with osteoporosis should be cautious of fracture risk even during daily activities.

  11. Fracture strength and stress distributions of pulpless premolars restored with fiber posts.

    Science.gov (United States)

    Furuya, Yu; Huang, Shih-Hao; Takeda, Yuko; Fok, Alex; Hayashi, Mikako

    2014-01-01

    This study examined the effect of glass fiber posts on increasing the fracture resistance of endodontically treated teeth. Extracted upper premolars with two canals in a root were divided into three groups according to the number of posts they were restored with: none, one, or two. All teeth were endodontically treated, crown-sectioned, and restored with a composite core and a metallic crown. A static oblique load was applied to the restored tooth until fracture, and the fracture pattern was recorded. Stress distributions were examined by finite element analysis (FEA). Teeth with glass fiber post(s) showed significantly higher fracture loads compared with those without posts. In the premolars without posts, von Mises and maximum principal stresses were found on the root surface alone; in premolars restored with posts, stresses were distributed on both root and post surfaces. Risk of root dentin fracture was significantly lowest in teeth restored with two posts.

  12. The influence of intrinsic disc degeneration of the adjacent segments on its stress distribution after one-level lumbar fusion.

    Science.gov (United States)

    Kim, Ho-Joong; Kang, Kyoung-Tak; Chun, Heoung-Jae; Lee, Choon-Ki; Chang, Bong-Soon; Yeom, Jin S

    2015-04-01

    The presence of degeneration alters the stress within that particular degenerated disc. Therefore, the state of degeneration of the disc at the level adjacent to a single level fusion would influence the rate of subsequent further degeneration of that same adjacent disc. Therefore, the purpose of this study was to investigate the biomechanical effect of the disc degeneration at the adjacent segment on the stress of the corresponding segment after one segment lumbar fusion using validated finite element (FE) models. Three validated L2-L5 FE models with different grades of disc degeneration (normal, mild, moderate) at the L2-L5 were simulated. Based on the intact models that represented each grade of disc degeneration, the matched L3-L4 instrumented fusion models were developed. Therefore, three intact models and three matched fusion models were simulated. Under the 400-N pre-compressive follower loading, 7.5 Nm moments simulating flexion, extension, lateral bending, and torsion in five steps were imposed on the L2 superior endplate of three intact models. The hybrid loading protocol was utilized for the fusion models. The intradiscal pressure and the maximal von Mises stress of the annulus fibrosus in the L2-L3 and L4-L5 segments were analyzed and compared between fusion and intact models with each grade of disc degeneration. Disc degeneration led to an increase of maximal von Mises stress of annulus fibrosus at this degenerated disc, related to disc degeneration under flexion, extension, lateral bending and torsion moments. Furthermore, the fusion also increased a maximal von Mises stress of annulus fibrous at both proximal and distal adjacent segments under hybrid protocol. The increases of annular stress were greater at the proximal adjacent segment than those at distal adjacent segment. However, the contribution of the fusion surgery to the increment rate of annulus fibrosus stress at the adjacent segment did not increase in relation with disc degeneration

  13. The effect of platform switching on stress distribution in implants and periimplant bone studied by nonlinear finite element analysis.

    Science.gov (United States)

    Liu, Siyu; Tang, Chunbo; Yu, Jinhua; Dai, Wenyong; Bao, Yidong; Hu, Dan

    2014-11-01

    It is unknown whether dental implant systems with a platform-switched configuration have better periimplant bone stress distribution and lead to less periimplant bone level changes. The purpose of this study was to quantitatively investigate interfacial stress and stress distribution in implant bone in 2 implant abutment designs (platform-switched design and conventional diameter matching) by using a nonlinear finite element analysis method. A finite element simulation study was applied to 2 commercially available dental implant systems: the Ankylos implant system with a reduced-diameter abutment (platform-switched implant) and the Anthogyr implant system with an abutment of the same diameter (regular platform implant). These 2 dental implant systems were positioned in a bone block, which was constructed based on a cross-sectional image of a human mandible in the molar region. In simulation, a single vertical load of 50 N, 100 N, or 150 N and horizontal loads of 50 N and 100 N were applied to the occlusal surface of the abutment. The finite element analysis found that the Ankylos implant system has a higher maximum von Mises stress in the implant abutment connection section and a lower maximum von Mises stress in the periimplant bone. The opposite results were found in the Anthogyr implant system. Lower stress levels in the periimplant bone with a more uniform stress distribution were found for the Ankylos implant system with a platform-switched configuration. Although relatively higher stress was found in the abutment, premature implant failure is not anticipated because of the high strength of titanium alloy. Copyright © 2014 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  14. von Willebrand Disease

    Science.gov (United States)

    ... for type 1 von Willebrand disease is called desmopressin. It causes a temporary increase in the von ... injection or by being sniffed into the nose. Desmopressin may also help some people with type 2 ...

  15. Interaktive Visualisierung von Strukturmechaniksimulationen

    OpenAIRE

    Sommer, Ove

    2003-01-01

    A) Motivation und Problemstellung Der Computer ist heute eines der wichtigsten Hilfsmittel beim Entwurf und der Entwicklung von Fahrzeugen. Zunächst wurde er von Konstrukteuren für das Computer Aided Design (CAD) von virtuellen Fahrzeugmodellen eingesetzt. Inzwischen ist er in vielen anderen Bereichen der Fahrzeugentwicklung unentbehrlich geworden: der Entwicklungszyklus von Automobilen ist durch die Computer-gestützte numerische Simulation substanziell verkürzt worden. An virtuellen Prot...

  16. Numerical investigation on effect of leaflet thickness on structural stresses developed in a bileaflet mechanical heart valve for its sustainable manufacturing

    Directory of Open Access Journals (Sweden)

    Abbas Syed Samar

    2017-01-01

    Full Text Available Flow induced structural stresses can cause mechanical prosthetic aortic valve to fail due to yielding. In this study, we have performed the structural analysis, especially the effect of leaflet thickness on equivalent stresses developed in a Bileaflet mechanical heart valve (BMHV due to blood flow through it has been investigated. The leaflet thickness varies from 0.5mm to 0.7mm, by 0.1mm. A fluid-structure interaction approach based on Arbitrary Lagrangian Eulerian (ALE technique has been employed with the aid of an user defined function (UDF. Results of the analysis show that high von Mises stresses are developed in BMHV with leaflet thickness of 0.5mm and 0.6mm, being 75% and 13% higher than allowable equivalent stress respectively. Such thinner leaflets are therefore, not sustainable to be replaced with diseased aortic valve.

  17. Class I and Class II restorations of resin composite: an FE analysis of the influence of modulus of elasticity on stresses generated by occlusal loading

    DEFF Research Database (Denmark)

    Asmussen, Erik; Peutzfeldt, Anne

    2008-01-01

    OBJECTIVES: It was the aim of the study to analyze by the FE method stresses generated in tooth and restoration by occlusal loading of Class I and Class II restorations of resin composite. On the basis of available information on the influence of the modulus of elasticity, the research hypothesis...... was that the marginal stresses would decrease with increasing modulus of elasticity of the restoration. METHODS: A cylindrical tooth was modelled in enamel and dentin and fitted with a Class I or a Class II restoration of resin composite. In one scenario the restoration was bonded to the tooth, in another...... the restoration was left nonbonded. The resin composite was modelled with a modulus of elasticity of 5, 10, 15 or 20 GPa and loaded occlusally with 100 N. By means of the soft-ware program ABAQUS the von Mises stresses in enamel and dentin were calculated. RESULTS: In the bonded scenario, the maximum stresses...

  18. Influence of the Angle of Cervical Convergence on Stresses to the PDL of Abutments: A 3D Analysis Using Finite Element Method

    Directory of Open Access Journals (Sweden)

    A. Geramy

    2007-03-01

    Full Text Available Objective: This study was designed to compare the stress produced at the PDL of abutment teeth with two angles of cervical convergence, in otherwise similar settings.Materials and Methods: Two finite element models were designed for a second premolar and a removable partial denture frame containing an I-bar clasp. Maximum Principal Stress (S1 and Von Mises Stress (SEQV were assessed along a cervicoapical path of nodes in the PDL.Results: Output data for S1 and SEQV were the same regarding the height of contour.A gradual decrease in both models was observed. A larger decrease was found in the model with the higher angle of cervical convergence.Conclusion: I-bars placed on teeth with lower angles of cervical convergence produce a higher stress to the PDL of abutments.

  19. Laser cutting of triangular geometry into 2024 aluminum alloy: Influence of triangle size on thermal stress field

    Energy Technology Data Exchange (ETDEWEB)

    Yilbas, Bekir Sami; Akhtar, Syed Sohail [King Fahd University of Petroleum and Minerals, Dhahran (Saudi Arabia); Keles, Omer; Boran, Kurtulus [Gazi University, Ankara (Turkmenistan)

    2015-08-15

    Laser cutting of a triangular geometry into aluminum 2024 alloy is carried out. Thermal stress field in the cutting section is predicted using the finite element code ABAQUS. Surface temperature predictions are validated through the thermocouple data. Morphological changes in the cut section are examined incorporating optical and electron scanning microscopes. The effects of the size of the triangular geometry on thermal stress field are also examined. It is found that surface temperature predictions agree well with thermocouple data. von Mises stress remains high in the region close to the corners of the triangular geometry, which is more pronounced for the small size triangle. This behavior is associated with the occurrence of the high cooling rates in this region. Laser cut edges are free from large scale sideways burning and large size burr attachments. However, some locally scattered dross attachments are observed at the kerf exit.

  20. Weighted Multivariate Cram´er-von Mises-type Statistics | Deheuvels ...

    African Journals Online (AJOL)

    In this paper, we consider weighted quadratic functionals of the multivariate uniform empirical process. By deriving the Karhunen-Lo`eve expansion of the corresponding limiting Gaussian process, we obtain the asymptotic distribution of these statistics. Our results have direct applications to tests of goodness of fit and tests ...

  1. Influence of implant collar design on stress and strain distribution in the crestal compact bone: a three-dimensional finite element analysis.

    Science.gov (United States)

    Shen, Wan-Ling; Chen, Chen-Sheng; Hsu, Ming-Lun

    2010-01-01

    To evaluate the influence of implant collar geometry on the distribution of stress and strain in the crestal compact bone contiguous to an implant collar for four types of bone under axial and oblique loads. Finite element models of threaded implants with three kinds of implant collar designs (divergent, straight, and convergent) with their corresponding suprastructures embedded in the posterior mandible were created with ANSYS software. Eight different test conditions incorporating four types of bone (orthotropic and effectively isotropic in part 1 and high and low densities in part 2) under separate 100-N axial and 35.6-degree oblique forces were created to investigate the stress and strain distributions in the crestal compact bone around the implant collars. In all eight conditions, the divergent collar demonstrated the lowest maximum von Mises and principal stresses and strains in the crestal compact bone contiguous to the implant collar, followed by the straight and convergent collars. The oblique load induced higher peak values than the axial load. The orthotropic design amplified and increased the pathologic microstrains and tensile stresses in the crestal compact bone compared to the effectively isotropic design, especially in models with a convergent collar design. In part 2 of the study, the maximum von Mises stresses and strains increased with a decrease in the cancellous bone density. Under oblique loading, the convergent and straight collars showed pathologic microstrain values as well as excessive ultimate tensile stresses in the orthotropic bone model with low-density cancellous bone. Within the limitations, it was concluded that stress and strain distributions in the adjacent compact bone are influenced by the implant collar design. The divergent implant collar design was associated with the lowest stress and strain concentrations in the crestal compact bone.

  2. Lernen von und bei Max von Laue

    Science.gov (United States)

    Thiessen, P. A.

    Erinnerungen an die Entstehungsgeschichte und die Frühzeiten der Röntgenstrukturanalyse.Translated AbstractLearning at Max von LaueRemembrances of the historical rise and the early times of X-ray structure analysis.

  3. Coupled Temperature Displacement Model to Predict Residual Stresses in Milling Process

    Science.gov (United States)

    Pramod, Monangi; Varun Reddy, Narahari; Talluru, Viswajit; Gopi Reddy, Yarkareddy; Marimuthu, Prakash K.

    2017-08-01

    Materials when subjected to plastic deformations, stresses are induced in the material. The stresses that are induced in the material due to machining is very high due to extreme plastic deformation. The nature and magnitude of the stresses plays a vital role in the functional performance of the components. The stresses can be tensile or compressive. Sometimes the stress are beneficial sometimes it is not. The present work is to develop a 2D coupled temperature displacement analysis to predict the surface residual stresses that are induced due to milling operation. In this work the material considered is AISI 1045 steel and the tool that is used is HSS tool. The finite element model is used to predict the residual stresses and it is compared with the experimental results. The predict results are in agreement with the experimental results. The residual stresses where experimentally determined using X-Ray diffraction method. Finite element method helps us to remove costly experiments and the process is rather quick. Apart from the residual stresses, force, temperature, Von Mises stress can also be obtained from the developed model.

  4. Active Von Willebrand Factor, thrombocytopenia and thrombosis

    NARCIS (Netherlands)

    Hulstein, J.J.J.

    2006-01-01

    Platelets and von Willebrand factor (VWF) are unable to interact in circulation. To induce an interaction, a conversion of VWF to a platelet-binding conformation is required. At higher shear stresses, the first step in thrombus formation is binding of VWF to the subendothelium. This results in

  5. Monitoring of stress relaxation and defect formation in metamorphic III-V semiconductor heterostructures for high-efficiency solar cells; Kontrolle von Spannungsrelaxation und Defektbildung in metamorphen III-V Halbleiterheterostrukturen fuer hocheffiziente Solarzellen

    Energy Technology Data Exchange (ETDEWEB)

    Schoene, Jan

    2009-07-21

    The paper discusses the further development of monolithic III-V multiple solar cells with three pn transitions for applications in concentrating PV systems. These triple solar cells consist of a GaInP upper cell, a GaInAs middle cell and a germanium lower cell, which are connected via electrically conducting and optically transparent tunnel diodes. Efficiencies are higher than 40 % with concentrated light. Demands on materials for III-V high-efficiency solar cells are extremely high. Especially in the metamorphic triple solar cell, for which compound semiconductors with different interatomic distances are deposited epitactically on each other, crystal defects may occur that impair the performance of the solar cell. The use of appropriate layer growing concepts may manipulate the formation of crystal defects and minimize their influence on solar cell performance. Both conventional and high-resolution transmission electron microscopy (TEM and HRTEM) as well as high-resolution X-ray diffraction (HRXRD) were applied successfully for investigating defect formation and layer stresses. In the investigations described, these methods were applied to develop a high-efficiency triple solar cell with a world first efficiency of 41.1 percent in concentrated light. [German] Diese Arbeit beschaeftigt sich mit der Weiterentwicklung von monolithischen III-V-Mehrfach-Solarzellen mit drei pn-Uebergaengen fuer die Anwendung in konzentrierenden Photovoltaiksystemen. Diese Tripelsolarzellen bestehen aus einer GaInP-Oberzelle, einer GaInAs-Mittelzelle und einer Germanium-Unterzelle, die mittels elektrisch leitender und optisch transparenter Tunneldioden verbunden sind. Derartige Solarzellen erzielen mittlerweile Rekordwirkungsgrade von mehr als 40 % unter konzentriertem Licht. Bei den III-V Hocheffizienzsolarzellen sind die Anforderungen an die Materialqualitaet ausserordentlich hoch. Insbesondere bei der metamorphen Tripelsolarzelle, bei der Verbindungshalbleiter mit unterschiedlichen

  6. Development of Mechanical Stress Simulator for Surface-Mount Devices

    Science.gov (United States)

    Yamamoto, Keiji

    1995-04-01

    A mechanical stress simulator for surface-mount devices was developed, which employed the finite-element method. The moisture distribution stage can calculate the moisture distribution of the LSI package exposed to temperature and humidity conditions. The heat conduction stage determines the time-dependent temperature distribution of the package immersed in a solder bath. Using the moisture and temperature distributions thus calculated, the mechanical stress stage gives the mechanical stress distribution in the package. Two groups of samples were prepared for solder dipping experiments. In one group, after dry baking for initialization, samples absorbed moisture by exposure at 30°C 85% (absorption process). In the other group, samples were exposed at 85°C 85% for 168 h and then dry-baked at 70°C (desorption process). These two groups have different moisture distributions in their packages. The results of solder dipping experiments are analyzed from the calculated mechanical stress values. In the absorption process, calculated maximum von Mises equivalent stress over the sectional molding compound \\barσ_max increases monotonically with absorption time. Then, \\barσ_max approaches its saturated value as absorption time tends to infinity. In the desorption process, \\barσ_max decreases with desorption time and approaches the thermal stress value when desorption time tends to infinity. These calculations explain the effect of moisture distribution on package cracking.

  7. A Numerical Investigation of the Thermal Stresses of a Planar Solid Oxide Fuel Cell

    Directory of Open Access Journals (Sweden)

    Paulina Pianko-Oprych

    2016-09-01

    Full Text Available A typical operating temperature of a solid oxide fuel cell (SOFC is quite high above 750 °C and affects the thermomechanical behavior of the cell. Thermal stresses may cause microstructural instability and sub-critical cracking. Therefore, a joint analysis by the computational fluid dynamics (CFD and computational structural mechanics based on the finite element method (FEM was carried out to analyze thermal stresses in a planar SOFC and to predict potential failure locations in the cell. A full numerical model was based on the coupling of thermo-fluid model with the thermo-mechanical model. Based on a temperature distribution from the thermo-fluid model, stress distribution including the von Mises stress, shear stress as well as the operating principal stress were derived in the thermo-mechanical model. The FEM calculations were performed under different working conditions of the planar SOFC. The highest total stress was noticed at the lower operating voltage of 0.3 V, while the lowest total stress was determined at the voltage of 0.7 V. The obtained stress distributions allowed a better understanding of details of internal processes occurring within the SOFC and provided helpful guidance in the optimization of a new SOFC design.

  8. Biomechanical effects of two different collar implant structures on stress distribution under cantilever fixed partial dentures.

    Science.gov (United States)

    Merıç, Gökçe; Erkmen, Erkan; Kurt, Ahmet; Eser, Atilim; özden, Ahmet Utku

    2011-11-01

    The purpose of the study was to compare the effects of two distinct collar geometries of implants on stress distribution in the bone around the implants supporting cantilever fixed partial dentures (CFPDs) as well as in the implant-abutment complex and superstructures. The three-dimensional finite element method was selected to evaluate the stress distribution. CFPDs which was supported by microthread collar structured (MCS) and non-microthread collar structured (NMCS) implants was modeled; 300 N vertical, 150 N oblique and 60 N horizontal forces were applied to the models separately. The stress values in the bone, implant-abutment complex and superstructures were calculated. In the MCS model, higher stresses were located in the cortical bone and implant-abutment complex in the case of vertical load while decreased stresses in cortical bone and implant-abutment complex were noted within horizontal and oblique loading. In the case of vertical load, decreased stresses have been noted in cancellous bone and framework. Upon horizontal and oblique loading, a MCS model had higher stress in cancellous bone and framework than the NMCS model. Higher von Mises stresses have been noted in veneering material for NMCS models. It has been concluded that stress distribution in implant-supported CFPDs correlated with the macro design of the implant collar and the direction of applied force.

  9. Evaluation de la mise en oeuvre des mesures de radioprotection ...

    African Journals Online (AJOL)

    Seulement 08.1% des services faisaient une surveillance médicale de leur personnel. Conclusion : Le niveau de mise en oeuvre des mesures de radioprotection des travailleurs dans les services de radiologie reste à améliorer et la création d'une autorité de réglementation est souhaitable pour une meilleure protection ...

  10. Effect of type of luting agents on stress distribution in the bone surrounding implants supporting a three-unit fixed dental prosthesis: 3D finite element analysis

    Science.gov (United States)

    Ghasemi, Ehsan; Abedian, Alireza; Iranmanesh, Pedram; Khazaei, Saber

    2015-01-01

    Background: Osseointegration of dental implants is influenced by many biomechanical factors that may be related to stress distribution. The aim of this study was to evaluate the effect of type of luting agent on stress distribution in the bone surrounding implants, which support a three-unit fixed dental prosthesis (FDP) using finite element (FE) analysis. Materials and Methods: A 3D FE model of a three-unit FDP was designed replacing the maxillary first molar with maxillary second premolar and second molar as the abutments using CATIA V5R18 software and analyzed with ABAQUS/CAE 6.6 version. The model was consisted of 465108 nodes and 86296 elements and the luting agent thickness was considered 25 μm. Three load conditions were applied on eight points in each functional cusp in horizontal (57.0 N), vertical (200.0 N) and oblique (400.0 N, θ = 120°) directions. Five different luting agents were evaluated. All materials were assumed to be linear elastic, homogeneous, time independent and isotropic. Results: For all luting agent types, the stress distribution pattern in the cortical bone, connectors, implant and abutment regions was almost uniform among the three loads. Furthermore, the maximum von Mises stress of the cortical bone was at the palatal side of second premolar. Likewise, the maximum von Mises stress in the connector region was in the top and bottom of this part. Conclusion: Luting agents transfer the load to cortical bone and different types of luting agents do not affect the pattern of load transfer. PMID:25709676

  11. Stress analysis of automotive ventilated disc brake rotor and pads using finite element method

    Directory of Open Access Journals (Sweden)

    A Belhocine

    2016-03-01

    Full Text Available The complexity of the physical or technological systems to be developed or studied led to employing numerical methods based on the principle of an approach as possible nominal solution, but these require large computations requiring efficient computers. The computer code ANSYS also allows the determination and the visualization of the structural deformations due to the contact of slipping between the disc and the pads. The results of the calculations of contact described in this work relate to displacements, Von Mises stress on the disc, contact pressures of the inner and outer pad at various moments of simulation. One precedes then the influence of some parameters on the computation results such as rotation of the disc, the smoothness of the mesh, the material of the brake pads and the friction coefficient enter the disc and the pads, the number of revolutions and the material of the disc, the pads groove.

  12. Contact Stress Generation on the UHMWPE Tibial Insert

    Directory of Open Access Journals (Sweden)

    S. Petrović Savić

    2014-12-01

    Full Text Available Total knee replacement (TKR is considered, during last years, as a very successful surgical technique for removing knee joint deformities and eliminating pain caused by cartilage damage. In literature, as primary causes for knee joint endoprothesis damage are cited complex movements which cause occurrences of complex stress conditions, sagital radius conformity, sliding, types of materials etc. Aim of this study is analysis of contact stresses that occur on tibial implant for 15°, 45° and 60° knee flexion and 50 kg, 75 kg, 100 kg and 125 kg weight. Knee joint prosthesis model and finite elements method (FEM analysis are done in software Catia V5. For this analysis we used ultra-high molecular weight polyethylene (UHMWPE for tibial implant material and AISI 316, AISI 317, AISI 321, 17-4PH, CoCrMo, Ti6Al4V and SAE A-286 for femoral component materials. Results show that area of maximal contact stress is identified in medial and lateral part of tibial implant. Von Mises stress values vary regarding of flexion degree and weight, but values are approximate for types of chosen materials. Contact stress location corresponds to damage that occur on tibial implant during exploitation.

  13. Effect of restoration volume on stresses in a mandibular molar: a finite element study.

    Science.gov (United States)

    Wayne, Jennifer S; Chande, Ruchi; Porter, H Christian; Janus, Charles

    2014-10-01

    There can be significant disagreement among dentists when planning treatment for a tooth with a failing medium-to-large--sized restoration. The clinician must determine whether the restoration should be replaced or treated with a crown, which covers and protects the remaining weakened tooth structure during function. The purpose of this study was to evaluate the stresses generated in different sized amalgam restorations via a computational modeling approach and reveal whether a predictable pattern emerges. A computer tomography scan was performed of an extracted mandibular first molar, and the resulting images were imported into a medical imaging software package for tissue segmentation. The software was used to separate the enamel, dentin, and pulp cavity through density thresholding and surface rendering. These tissue structures then were imported into 3-dimensional computer-aided design software in which material properties appropriate to the tissues in the model were assigned. A static finite element analysis was conducted to investigate the stresses that result from normal occlusal forces. Five models were analyzed, 1 with no restoration and 4 with increasingly larger restoration volume proportions: a normal-sized tooth, a small-sized restoration, 2 medium-sized restorations, and 1 large restoration as determined from bitewing radiographs and occlusal surface digital photographs. The resulting von Mises stresses for dentin-enamel of the loaded portion of the tooth grew progressively greater as the size of the restoration increased. The average stress in the normal, unrestored tooth was 4.13 MPa, whereas the smallest restoration size increased this stress to 5.52 MPa. The largest restoration had a dentin-enamel stress of 6.47 MPa. A linear correlation existed between restoration size and dentin-enamel stress, with an R(2) of 0.97. A larger restoration volume proportion resulted in higher dentin-enamel stresses under static loading. A comparison of the von Mises

  14. von Willebrand Disease

    Science.gov (United States)

    ... the condition. For example, the school nurse, teacher, daycare provider, coach, or any leader of afterschool activities ... MedlinePlus) Von Willebrand Disease (MedlinePlus) Building 31 31 Center Drive Bethesda, MD 20892 Learn more about getting ...

  15. Carl von Clausewitz

    DEFF Research Database (Denmark)

    Højrup, Thomas

    2009-01-01

    Forskningsbaseret præsentation af Carl von Clausewitz' krigsteori og dens betydning for statsbegrebet og udviklingen af teori om statsdannelse og statssystem. Krigsbegrebets betydning for politikbegrebet ekspliciteres, og de indre relationer imellem de to begreber demonstreres med konkrete eksemp...

  16. Ellis Von Creveld Syndrome

    Directory of Open Access Journals (Sweden)

    Afshar H

    1999-01-01

    Full Text Available One patient with Ellis Von Creveld syndrome contains: dwarfism, congenital heart"ndisease, ectodermal dysplasia, polyductyly, an abnormally wide labial frenum and maxillary"nmolars with single root.

  17. The three-dimension finite element analysis of stress in posterior tooth residual root restored with postcore crown.

    Science.gov (United States)

    Fu, Gang; Deng, Feng; Wang, Lu; Ren, Aishu

    2010-02-01

    Teeth that have been endodontically treated and restored with postcore crown may experience fracture sometimes. Some researchers have analyzed the stress of the anterior teeth after postcore crown restoration, but the stress of the posterior teeth after such restoration has not been reported. We used three-dimension finite element methods to analyze the stress magnitude and distribution of remaining dentin in posterior tooth residual root restored with postcore crown. The binding material, loading direction, number, length and material of posts were studied. The models of residual root of maxillary first molar restored with postcore crown were created by CT scanning, mimics software and abaqus software. Different number, length and material of posts were used in the modeling. The posts were cemented with zinc-phosphate cement or composited resin. A load of 240 N was applied to the occlusal surface in four directions and tensile, shear, and von Mises stresses were calculated. (i) The maximum stress on remaining dentin changed irregularly as the number and length of posts changed. (ii) The maximum stress on remaining dentin decreased slightly as elastic modulus of the material of posts increased. (iii) The maximum stress on bonding layer and remaining dentin was lower when bonded with resin luting agent than with zinc-phosphate cement. (iv) The maximum stress on remaining dentin increased markedly as loading angle increased. The number, length, material of posts, bonding material and loading angle all have influence on the magnitude and distribution of stress. The influence of loading angle is most apparent.

  18. Three-dimensional stress analysis of O-ring under uniform squeeze and internal pressure by photoelastic experimental hybrid method

    Science.gov (United States)

    Hawong, J. S.; Nam, J. H.; Liu, Y.; Shin, D. C.

    2010-03-01

    Until now, it is known that stresses on the plane (y-z plane) perpendicular to the circumferential direction (x axis) of Oring exist and stresses on the plane (x-y plane and x-z plane) parallel to the circumferential direction of O-ring does not exist when O-ring is under uniform squeeze rate and internal pressure. But it was known that stresses of x-y plane and xz plane of O-ring under uniform squeeze and internal pressure were existed by this research. To analyze 3 dimensional stress distributions of O-ring under those loadings, stress distributions of every plane should be analyzed. Therefore, photoelastic experimental hybrid method for 3 dimensional stress distributions of O-ring under uniform squeeze and internal pressure were developed in this research. Photoelastic experimental procedures for 3 dimensional stress distributions of O-ring under those loadings were introduced. Stress distributions of O-ring under those loadings were analyzed by photoelastic experimental hybrid method developed in this research. Von Mises equivalent stresses at arbitrary point of O-ring under those loadings were analyzed.

  19. Sarcomas as a mise en abyme of mesenchymal stem cells

    DEFF Research Database (Denmark)

    Burns, Jorge S.; Safwat, Akmal Ahmed; Grisendi, Giulia

    2012-01-01

    Mise en abyme meaning "placed into abyss or infinite recurrence" is an apt paradigm for the relentless growth of sarcoma cells. Its alternative meaning, "self-reflexive embedding" fits the central role attributed to cancer stem cells (CSCs). Diversely sourced and defined, mesenchymal stem cells...... (MSCs) may be the cells of sarcoma origin, evolve a CSC phenotype and/or contribute to tumor growth through inherent qualities for homing, neovascularization, paracrine cross-feeding, microvesicle secretion, cell fusion, entosis and immune modulation. Exploiting these qualities, MSC expressing modified...

  20. Creep Modeling in a Composite Rotating Disc with Thickness Variation in Presence of Residual Stress

    Directory of Open Access Journals (Sweden)

    Vandana Gupta

    2012-01-01

    Full Text Available Steady-state creep response in a rotating disc made of Al-SiC (particle composite having linearly varying thickness has been carried out using isotropic/anisotropic Hoffman yield criterion and results are compared with those using von Mises yield criterion/Hill's criterion ignoring difference in yield stresses. The steady-state creep behavior has been described by Sherby's creep law. The material parameters characterizing difference in yield stresses have been used from the available experimental results in literature. Stress and strain rate distributions developed due to rotation have been calculated. It is concluded that the stress and strain distributions got affected from the thermal residual stress in an isotropic/anisotropic rotating disc, although the effect of residual stress on creep behavior in an anisotropic rotating disc is observed to be lower than those observed in an isotropic disc. Thus, the presence of residual stress in composite rotating disc with varying thickness needs attention for designing a disc.

  1. Multibody Dynamic Stress Simulation of Rigid-Flexible Shovel Crawler Shoes

    Directory of Open Access Journals (Sweden)

    Samuel Frimpong

    2016-06-01

    Full Text Available Electric shovels are used in surface mining operations to achieve economic production capacities. The capital investments and operating costs associated with the shovels deployed in the Athabasca oil sands formation are high due to the abrasive conditions. The shovel crawler shoes interact with sharp and abrasive sand particles, and, thus, are subjected to high transient dynamic stresses. These high stresses cause wear and tear leading to crack initiation, propagation and premature fatigue failure. The objective of this paper is to develop a model to characterize the crawler stresses and deformation for the P&H 4100C BOSS during propel and loading using rigid-flexible multi-body dynamic theory. A 3-D virtual prototype model of the rigid-flexible crawler track assembly and its interactions with oil sand formation is simulated to capture the model dynamics within multibody dynamics software MSC ADAMS. The modal and stress shapes and modal loads due to machine weight for each flexible crawler shoes are generated from finite element analysis (FEA. The modal coordinates from the simulation are combined with mode and stress shapes using modal superposition method to calculate real-time stresses and deformation of flexible crawler shoes. The results show a maximum von Mises stress value of 170 MPa occurring in the driving crawler shoe during the propel motion. This study provides a foundation for the subsequent fatigue life analysis of crawler shoes for extending crawler service life.

  2. Finite element analysis of stresses in fixed prosthesis and cement layer using a three-dimensional model

    Directory of Open Access Journals (Sweden)

    Arunachalam Sangeetha

    2012-01-01

    Full Text Available Context: To understand the effect of masticatory and parafunctional forces on the integrity of the prosthesis and the underlying cement layer. Aims: The purpose of this study was to evaluate the stress pattern in the cement layer and the fixed prosthesis, on subjecting a three-dimensional finite element model to simulated occlusal loading. Materials and Methods: Three-dimensional finite element model was simulated to replace missing mandibular first molar with second premolar and second molar as abutments. The model was subjected to a range of occlusal loads (20, 30, 40 MPa in two different directions - vertical and 30° to the vertical. The cements (zinc phosphate, polycarboxylate, glass ionomer, and composite were modeled with two cement thicknesses - 25 and 100 μm. Stresses were determined in certain reference points in fixed prosthesis and the cement layer. Statistical Analysis Used: The stress values are mathematic calculations without variance; hence, statistical analysis is not routinely required. Results: Stress levels were calculated according to Von Mises criteria for each node. Maximum stresses were recorded at the occlusal surface, axio-gingival corners, followed by axial wall. The stresses were greater with lateral load and with 100-μm cement thickness. Results revealed higher stresses for zinc phosphate cement, followed by composites. Conclusions: The thinner cement interfaces favor the success of the prosthesis. The stresses in the prosthesis suggest rounding of axio-gingival corners and a well-established finish line as important factors in maintaining the integrity of the prosthesis.

  3. Stress analysis of different configurations of 3 implants to support a fixed prosthesis in an edentulous jaw

    Directory of Open Access Journals (Sweden)

    João Paulo da Silva-Neto

    2014-01-01

    Full Text Available This study's aims was to evaluate the stress distribution in a mandibular implant-supported prosthesis and peri-implant bone considering implant quantity, diameter and position using linear 3-D finite element analysis. Models of an anterior jaw comprised 4 groups according to implant quantity, diameter, and position: control group C, 5 regular implants; R, 3 regular implants; W, 3 wide implants; and DTR, 3 regular implants with the distal ones tilted 30º distally. The cantilever was loaded with an axial load of 50 N. Data was evaluated using von Mises stress on implants and maximum principal stress and microstrain on the bone. The W group showed the lowest value of maximum principal stress in peri-implant bone of the loaded side (4.64 MPa when compared to C (5.27 MPa, DTR (5.94 MPa, and R (11.12 MPa. Lower stress values in the loaded implants were observed in the experimental groups when compared to the C group. However, the unloaded implants presented opposite results. All the screws of the W group presented lower stress values when compared to the C group. However, the R and DTR groups presented an increase in stress values with the exception of the loaded screw. A reduction in the number of implants associated with wider implants reduced the stress in the bone and prosthetic components.

  4. The Effect of Composite Thickness on the Stress Distribution Pattern of Restored Premolar Teeth with Cusp Reduction.

    Science.gov (United States)

    Panahandeh, Narges; Torabzadeh, Hassan; Ziaee, Nargess; Mahdian, Mina; Tootiaee, Bahman; Ghasemi, Amir

    2017-07-01

    Different thicknesses of restorative material can alter the stress distribution pattern in remaining tooth structure. The assumption is that a thicker composite restoration will induce a higher fracture resistance. Therefore, the present study evaluated the effect of composite thickness on stress distribution in a restored premolar with cusp reduction. A 3D solid model of a maxillary second premolar was prepared and meshed. MOD cavities were designed with different cusp reduction thicknesses (0, 0.5, 1, 1.5, 2.5 mm). Cavities were restored with Valux Plus composite. They were loaded with 200 N force on the occlusal surface in the direction of the long axis. Von Mises stresses were evaluated with Abaqus software. Stress increased from occlusal to gingival and was maximum in the cervical region. The stressed area in the palatal cusp was more than that of the buccal cusp. Increasing the thickness of composite altered the shear stress to compressive stress in the occlusal area of the teeth. The model with 2.5 mm cusp reduction exhibited the most even stress distribution. © 2015 by the American College of Prosthodontists.

  5. Overdenture retaining bar stress distribution: a finite-element analysis.

    Science.gov (United States)

    Caetano, Conrado Reinoldes; Mesquita, Marcelo Ferraz; Consani, Rafael Leonardo Xediek; Correr-Sobrinho, Lourenço; Dos Santos, Mateus Bertolini Fernandes

    2015-05-01

    Evaluate the stress distribution on the peri-implant bone tissue and prosthetic components of bar-clip retaining systems for overdentures presenting different implant inclinations, vertical misfit and framework material. Three-dimensional models of a jaw and an overdenture retained by two implants and a bar-clip attachment were modeled using specific software (SolidWorks 2010). The studied variables were: latero-lateral inclination of one implant (-10°, -5°, 0°, +5°, +10°); vertical misfit on the other implant (50, 100, 200 µm); and framework material (Au type IV, Ag-Pd, Ti cp, Co-Cr). Solid models were imported into mechanical simulation software (ANSYS Workbench 11). All nodes on the bone's external surface were constrained and a displacement was applied to simulate the settling of the framework on the ill-fitted component. Von Mises stress for the prosthetic components and maximum principal stress to the bone tissue were evaluated. The +10° inclination presented the worst biomechanical behavior, promoting the highest stress values on the bar framework and peri-implant bone tissue. The -5° group presented the lowest stress values on the prosthetic components and the lowest stress value on peri-implant bone tissue was observed in -10°. Increased vertical misfit caused an increase on the stress values in all evaluated structures. Stiffer framework materials caused a considerable stress increase in the framework itself, prosthetic screw of the fitted component and peri-implant bone tissue. Inclination of one implant associated with vertical misfit caused a relevant effect on the stress distribution in bar-clip retained overdentures. Different framework materials promoted increased levels of stress in all the evaluated structures.

  6. A comparison of head dynamic response and brain tissue stress and strain using accident reconstructions for concussion, concussion with persistent postconcussive symptoms, and subdural hematoma.

    Science.gov (United States)

    Oeur, R Anna; Karton, Clara; Post, Andrew; Rousseau, Philippe; Hoshizaki, T Blaine; Marshall, Shawn; Brien, Susan E; Smith, Aynsley; Cusimano, Michael D; Gilchrist, Michael D

    2015-08-01

    Concussions typically resolve within several days, but in a few cases the symptoms last for a month or longer and are termed persistent postconcussive symptoms (PPCS). These persisting symptoms may also be associated with more serious brain trauma similar to subdural hematoma (SDH). The objective of this study was to investigate the head dynamic and brain tissue responses of injury reconstructions resulting in concussion, PPCS, and SDH. Reconstruction cases were obtained from sports medicine clinics and hospitals. All subjects received a direct blow to the head resulting in symptoms. Those symptoms that resolved in 9 days or fewer were defined as concussions (n = 3). Those with symptoms lasting longer than 18 months were defined as PPCS (n = 3), and 3 patients presented with SDHs (n = 3). A Hybrid III headform was used in reconstruction to obtain linear and rotational accelerations of the head. These dynamic response data were then input into the University College Dublin Brain Trauma Model to calculate maximum principal strain and von Mises stress. A Kruskal-Wallis test followed by Tukey post hoc tests were used to compare head dynamic and brain tissue responses between injury groups. Statistical significance was set at p concussion group (149 g and 8111 rad/sec(2), respectively; p brain tissue measures of maximum principal strain or von Mises stress. The reconstruction of accidents resulting in a concussion with transient symptoms (low severity) and SDHs revealed a positive relationship between an increase in head dynamic response and the risk for more serious brain injury. This type of relationship was not found for brain tissue stress and strain results derived by finite element analysis. Future research should be undertaken using a larger sample size to confirm these initial findings. Understanding the relationship between the head dynamic and brain tissue response and the nature of the injury provides important information for developing strategies for injury

  7. Bone stress and strain modification in diastema closure: 3D analysis using finite element method.

    Science.gov (United States)

    Geramy, Allahyar; Bouserhal, Joseph; Martin, Domingo; Baghaeian, Pedram

    2015-09-01

    The aim of this study was to analyse the stress and strain distribution in the alveolar bone between two central incisors in the process of diastema closure with a constant force. A 3-dimensional computer modeling based on finite element techniques was used for this purpose. A model of an anterior segment of the mandible containing cortical bone, spongy bone, gingivae, PDL and two central incisors with a bracket in the labial surface of each tooth were designed. The von Mises stress and strain was evaluated in alveolar bone along a path of nodes defined in a cresto-apical direction in the midline between two teeth. It was observed that stress and strain of alveolar bone increased in midline with a constant force to close the diastema regardless of the type of movement in gradual steps of diastema closure, however the stress was higher in the tipping movement than the bodily so it can be suggested that a protocol of force system modification should be introduced to compensate for the stress and strain changes caused by the reduced distance to avoid the unwanted stress alteration during the diastema closure. Copyright © 2015. Published by Elsevier Masson SAS.

  8. Stress analysis in bone tissue around single implants with different diameters and veneering materials: a 3-D finite element study.

    Science.gov (United States)

    Santiago Junior, Joel Ferreira; Pellizzer, Eduardo Piza; Verri, Fellippo Ramos; de Carvalho, Paulo Sérgio Perri

    2013-12-01

    The aim of this study was to evaluate the stress distribution on bone tissue with a single prosthesis supported by implants of large and conventional diameter and presenting different veneering materials using the 3-D finite element method. Sixteen models were fabricated to reproduce a bone block with implants, using two diameters (3.75×10 mm and 5.00×10 mm), four different veneering materials (composite resin, acrylic resin, porcelain, and NiCr crown), and two loads (axial (200 N) and oblique (100 N)). For data analysis, the maximum principal stress and von Mises criterion were used. For the axial load, the cortical bone in all models did not exhibit significant differences, and the trabecular bone presented higher tensile stress with reduced implant diameter. For the oblique load, the cortical bone presented a significant increase in tensile stress on the same side as the loading for smaller implant diameters. The trabecular bone showed a similar but more discreet trend. There was no difference in bone tissue with different veneering materials. The veneering material did not influence the stress distribution in the supporting tissues of single implant-supported prostheses. The large-diameter implants improved the transference of occlusal loads to bone tissue and decreased stress mainly under oblique loads. Oblique loading was more detrimental to distribution stresses than axial loading. © 2013.

  9. The role of prosthetic abutment material on the stress distribution in a maxillary single implant-supported fixed prosthesis

    Energy Technology Data Exchange (ETDEWEB)

    Peixoto, Hugo Eduardo, E-mail: hugo.e.peixoto@hotmail.com [Implantology Team, Latin American Institute of Research and Education in Dentistry, Curitiba, Paraná (Brazil); Bordin, Dimorvan, E-mail: dimorvan_bordin@hotmail.com [Department of Prosthodontics and Periodontology, Piracicaba Dental School, State University of Campinas, Limeira avenue, 901-Vila Rezende, Piracicaba, SP 13414-903 (Brazil); Del Bel Cury, Altair A., E-mail: altcury@fop.unicamp.br [Department of Prosthodontics and Periodontology, Piracicaba Dental School, State University of Campinas, Limeira avenue, 901-Vila Rezende, Piracicaba, SP 13414-903 (Brazil); Silva, Wander José da, E-mail: wanderjose@fop.unicamp.br [Department of Prosthodontics and Periodontology, Piracicaba Dental School, State University of Campinas, Limeira avenue, 901-Vila Rezende, Piracicaba, SP 13414-903 (Brazil); Faot, Fernanda, E-mail: fernanda.faot@gmail.com [Department of Restorative Dentistry, School of Dentistry, Federal University of Pelotas, Gonçalves Chaves, 457, 2nd floor, Pelotas, Rio Grande do Sul 96015-560 (Brazil)

    2016-08-01

    Purpose: Evaluate the influence of abutment's material and geometry on stress distribution in a single implant-supported prosthesis. Materials and Methods: Three-dimensional models were made based on tomographic slices of the upper middle incisor area, in which a morse taper implant was positioned and a titanium (Ti) or zirconia (ZrN) universal abutments was installed. The commercially available geometry of titanium (T) and zirconia (Z) abutments were used to draw two models, TM1 and ZM1 respectively, which served as control groups. These models were compared with 2 experimental groups were the mechanical properties of Z were applied to the titanium abutment (TM2) and vice versa for the zirconia abutment (ZM2). Subsequently, loading was simulated in two steps, starting with a preload phase, calculated with the respective friction coefficients of each materials, followed by a combined preload and chewing force. The maximum von Mises stress was described. Data were analyzed by two-way ANOVA that considered material composition, geometry and loading (p < 0.05). Results: Titanium and zirconia abutments showed similar von Mises stresses in the mechanical part of the four models. The area with the highest concentration of stress was the screw thread, following by the screw body. The highest stress levels occurred in screw thread was observed during the preloading phase in the ZM1 model (931 MPa); and during the combined loading in the TM1 model (965 MPa). Statistically significant differences were observed for loading, the material × loading interaction, and the loading × geometry interaction (p < 0.05). Preloading contributed for 77.89% of the stress (p < 0.05). There were no statistically significant differences to the other factors (p > 0.05). Conclusion: The screw was the piece most intensely affected, mainly through the preload force, independent of the abutment's material. - Highlights: • The abutment's screw was the most impaired piece of the

  10. Von Braun Fountain

    Science.gov (United States)

    1999-01-01

    A fountain representing a rocket launch was dedicated in the Von Braun courtyard outside of Building 4200 at Marshall Space Flight Center during the weekend celebrating the 30th arniversary of the Apollo 11 lunar landing. On hand for the festivities were many of the Saturn and Apollo astronauts.

  11. Rhizostomeen von Manila

    NARCIS (Netherlands)

    Stiasny, G.

    1924-01-01

    Die hier beschriebene kleine Scyphomedusen-Sammlung wurde von Herrn Director P. B. Sivickis, Dept. of Zoology, University of Philippines, Manila, dem Rijksmuseum van Natuurlijke Historie in Leiden überwiesen. Das Material wurde im December 1922 in Manila-bay gefischt und befindet sich in bestem

  12. Karman, Prof. Theodore von

    Indian Academy of Sciences (India)

    Home; Fellowship. Fellow Profile. Elected: 1961 Honorary. Karman, Prof. Theodore von. Date of birth: 11 May 1881. Date of death: 6 May 1963. YouTube; Twitter; Facebook; Blog. Academy News. IAS Logo. Theory Of Evolution. Posted on 23 January 2018. Joint Statement by the Three Science Academies of India on the ...

  13. Schmetterlinge von Madeira

    NARCIS (Netherlands)

    Martin, K.

    1941-01-01

    Wer auf einer ozeanischen Insel Schmetterlinge sammeln will, darf seine Erwartungen nicht zu hoch spannen; aber dennoch waren meine Frau und ich sehr enttäuscht, als uns auf einer Reise nach Madeira von einer dort angesessenen, gebildeten Dame gesagt wurde, sie habe auf der Insel niemals einen

  14. Effect of the number of implants on stress distribution of anterior implant-supported fixed prostheses combined with a removable partial denture: a finite element analysis.

    Science.gov (United States)

    Mahshid, Minoo; Geramy, Allahyar; Ejlali, Massoud; Sedaghat Monfared, Majid; Rezvani Habib Abadi, Shirin

    2014-05-01

    The main goal of this study was to evaluate differences in stress distribution relevant to the number of implants under an anterior bridge when combined with a removable partial denture in the posterior region. Four three-dimensional finite element models (3D FEM) were designed from a mandible containing an implant-supported bridge extending between canines, and a bilateral distal extension removable partial denture. A nonrigid connection was selected as the attachment method between the partial denture and the anterior implant-supported fixed prosthesis; 2, 3, 4 and 5 implants supporting the bridge all with 10mm length and 3.8 mm diameter were assessed. With the aid of the finite element program ANSYS 8.0, the models were loaded and von Mises stresses were evaluated. In spongy bone, stress forces showed a decrease from 2 implants to 4 implants but showed an increase in the 5-implant model. Stresses on cortical bone of terminal implants were in similar range in the 2-, 3- and 4-implant models. While, in the 5-implant model the amount of stresses on terminal implants increased dramatically. The stresses on implants were nearly similar in all models, with the greatest amount on terminal implants. Within the limitations of this study, 2-, 3- and 4-implant models showed less stress on cortical and spongy bone in comparison with the 5-implant model. The stresses transferred to implants were nearly similar.

  15. Effect of the number of implants on stress distribution of anterior implant-supported fixed prostheses combined with a removable partial denture: a finite element analysis.

    Directory of Open Access Journals (Sweden)

    Minoo Mahshid

    2014-06-01

    Full Text Available The main goal of this study was to evaluate differences in stress distribution relevant to the number of implants under an anterior bridge when combined with a removable partial denture in the posterior region.Four three-dimensional finite element models (3D FEM were designed from a mandible containing an implant-supported bridge extending between canines, and a bilateral distal extension removable partial denture. A nonrigid connection was selected as the attachment method between the partial denture and the anterior implant-supported fixed prosthesis; 2, 3, 4 and 5 implants supporting the bridge all with 10mm length and 3.8 mm diameter were assessed. With the aid of the finite element program ANSYS 8.0, the models were loaded and von Mises stresses were evaluated.In spongy bone, stress forces showed a decrease from 2 implants to 4 implants but showed an increase in the 5-implant model. Stresses on cortical bone of terminal implants were in similar range in the 2-, 3- and 4-implant models. While, in the 5-implant model the amount of stresses on terminal implants increased dramatically. The stresses on implants were nearly similar in all models, with the greatest amount on terminal implants.Within the limitations of this study, 2-, 3- and 4-implant models showed less stress on cortical and spongy bone in comparison with the 5-implant model. The stresses transferred to implants were nearly similar.

  16. A Challenge to Ludwig von Mises’s Theory of Probability

    Directory of Open Access Journals (Sweden)

    Mark R. Crovelli

    2010-10-01

    Full Text Available The most interesting and completely overlooked aspect of Ludwig von Mises’s theory of probability is the total absence of any explicit definition for probability in his theory. This paper examines Mises’s theory of probability in light of the fact that his theory possesses no definition for probability. It is argued, first, that Mises’s theory differs in important respects from his brother’s famous theory of probability. A defense of the subjective definition for probability is then provided, which is subsequently used to critique Ludwig von Mises’s theory. It is argued that only the subjective definition for probability comports with Mises’s other philosophical positions. Since Mises did not provide an explicit definition for probability, it is suggested that he ought to have adopted a subjective definition.

  17. Mechanical characterization and modeling of brazed tungsten and Cu-Cr-Zr alloy using stress relief interlayers

    Science.gov (United States)

    Qu, Dandan; Zhou, Zhangjian; Yum, Youngjin; Aktaa, Jarir

    2014-12-01

    A rapidly solidified foil-type Ti-Zr based amorphous filler with a melting temperature of 850 °C was used to braze tungsten to Cu-Cr-Zr alloy for water cooled divertors and plasma facing components application. Brazed joints of dissimilar materials suffer from a mismatch in coefficients of thermal expansion. In order to release the residual stress caused by the mismatch, brazed joints of tungsten and Cu-Cr-Zr alloy using different interlayers were studied. The shear strength tests of brazed W/Cu joints show that the average strength of the joint with a W70Cu30 composite plate interlayer reached 119.8 MPa, and the average strength of the joint with oxygen free high conductivity copper (OFHC Cu)/Mo multi-interlayers reached 140.8 MPa, while the joint without interlayer was only 16.6 MPa. Finite element method (FEM) has been performed to investigate the stress distribution and effect of stress relief interlayers. FEM results show that the maximum von Mises stress occurs in the tungsten/filler interface and that the filler suffers the peak residual stresses and becomes the weakest zone. And the use of OFHC Cu/Mo multi-interlayers can reduce the residual stress significantly, which agrees with the mechanical experiment data.

  18. Spatial variability in the coefficient of thermal expansion induces pre-service stresses in computer models of virgin Gilsocarbon bricks

    Energy Technology Data Exchange (ETDEWEB)

    Arregui-Mena, José David, E-mail: jose.arreguimena@postgrad.manchester.ac.uk [School of Mechanical, Aerospace, and Civil Engineering, University of Manchester, Oxford Road, Manchester, M13 9PL (United Kingdom); Margetts, Lee, E-mail: lee.margetts@manchester.ac.uk [School of Mechanical, Aerospace, and Civil Engineering, University of Manchester, Oxford Road, Manchester, M13 9PL (United Kingdom); Griffiths, D.V., E-mail: d.v.griffiths@mines.edu [Colorado School of Mines, 1500 Illinois St, Golden, CO 80401 (United States); Lever, Louise, E-mail: louise.lever@manchester.ac.uk [Research Computing, University of Manchester, Oxford Road, Manchester, M13 9PL (United Kingdom); Hall, Graham, E-mail: graham.n.hall@manchester.ac.uk [School of Mechanical, Aerospace, and Civil Engineering, University of Manchester, Oxford Road, Manchester, M13 9PL (United Kingdom); Mummery, Paul M., E-mail: paul.m.mummery@manchester.ac.uk [School of Mechanical, Aerospace, and Civil Engineering, University of Manchester, Oxford Road, Manchester, M13 9PL (United Kingdom)

    2015-10-15

    In this paper, the authors test the hypothesis that tiny spatial variations in material properties may lead to significant pre-service stresses in virgin graphite bricks. To do this, they have customised ParaFEM, an open source parallel finite element package, adding support for stochastic thermo-mechanical analysis using the Monte Carlo Simulation method. For an Advanced Gas-cooled Reactor brick, three heating cases have been examined: a uniform temperature change; a uniform temperature gradient applied through the thickness of the brick and a simulated temperature profile from an operating reactor. Results are compared for mean and stochastic properties. These show that, for the proof-of-concept analyses carried out, the pre-service von Mises stress is around twenty times higher when spatial variability of material properties is introduced. The paper demonstrates that thermal gradients coupled with material incompatibilities may be important in the generation of stress in nuclear graphite reactor bricks. Tiny spatial variations in coefficient of thermal expansion (CTE) and Young's modulus can lead to the presence of thermal stresses in bricks that are free to expand. - Highlights: • Open source software has been modified to include random variability in CTE and Young's modulus. • The new software closely agrees with analytical solutions and commercial software. • Spatial variations in CTE and Young's modulus produce stresses that do not occur with mean values. • Material variability may induce pre-service stress in virgin graphite.

  19. Extrasinus zygomatic implant placement in the rehabilitation of the atrophic maxilla: three-dimensional finite element stress analysis.

    Science.gov (United States)

    Romeed, Shihab A; Hays, Robert Nigel; Malik, Raheel; Dunne, Stephen M

    2015-04-01

    Placement of zygomatic implants lateral to the maxillary sinus, according to the extrasinus protocol, is one of the treatment options in the rehabilitation of severely atrophic maxilla or following maxillectomy surgery in patients with head and neck cancer. The aim of this study was to investigate the mechanical behavior of a full-arch fixed prosthesis supported by 4 zygomatic implants in the atrophic maxilla under occlusal loading. Results indicated that maximum von Mises stresses were significantly higher under lateral loading compared with vertical loading within the prosthesis and its supporting implants. Peak stresses were concentrated at the prosthesis-abutments interface under vertical loading and the internal line angles of the prosthesis under lateral loading. The zygomatic supporting bone suffered significantly lower stresses. However, the alveolar bone suffered a comparatively higher level of stresses, particularly under lateral loading. Prosthesis displacement under vertical loading was higher than under lateral loading. The zygomatic bone suffered lower stresses than the alveolar bone and prosthesis-implant complex under both vertical and lateral loading. Lateral loading caused a higher level of stresses than vertical loading.

  20. To reduce the maximum stress and the stress shielding effect around a dental implant-bone interface using radial functionally graded biomaterials.

    Science.gov (United States)

    Asgharzadeh Shirazi, H; Ayatollahi, M R; Asnafi, A

    2017-05-01

    In a dental implant system, the value of stress and its distribution plays a pivotal role on the strength, durability and life of the implant-bone system. A typical implant consists of a Titanium core and a thin layer of biocompatible material such as the hydroxyapatite. This coating has a wide range of clinical applications in orthopedics and dentistry due to its biocompatibility and bioactivity characteristics. Low bonding strength and sudden variation of mechanical properties between the coating and the metallic layers are the main disadvantages of such common implants. To overcome these problems, a radial distributed functionally graded biomaterial (FGBM) was proposed in this paper and the effect of material property on the stress distribution around the dental implant-bone interface was studied. A three-dimensional finite element simulation was used to illustrate how the use of radial FGBM dental implant can reduce the maximum von Mises stress and, also the stress shielding effect in both the cortical and cancellous bones. The results, of course, give anybody an idea about optimized behaviors that can be achieved using such materials. The finite element solver was validated by familiar methods and the results were compared to previous works in the literature.

  1. Ecoulement et mise en structure de suspensions macroscopiques

    Science.gov (United States)

    Petit, L.

    In this review, we report the various experimental studies performed on suspensions of solid particules in liquids, and concerning the rheological behaviour of such systems and the ordering of particules under the applied velocity fields. The number of materials which are flowing suspensions (reagents in chemical engineering, paints while spreading, blood flow, muds in oil reservoir) gave rise to a number of experimental studies, especially in the last twenty years. The results show a wide variety of behaviour, even for systems of intermediate concentration. In addition, even for identical systems, the results depend of the type of flow. Then, it is clear that, in addition of the standard parameters which are to be taken into account, it is necessary to consider the type of flow the suspension is submitted to. The flow influences the spatial distribution of the particules, leading to their ordering or migration. These ordering or motions influence the flow, and then, the rheological behaviour of the whole system. So, there is a feedback mechanism from the ordering to the flow, which explains the experimental observations. Nous reportons dans cette revue les différentes études expérimentales réalisées sur les suspensions de particules solides dans un liquide et qui concernent le comportement rhéologique de ces systèmes ainsi que les mouvements des particules sous l'effet des champs de vitesse imposés. Ces mouvements peuvent conduire soit à des mises en structure, ou encore à des migrations des particules. L'importance du nombre de matériaux qui se présentent sous forme de suspension et qui sont mis en écoulement (réactif en génie chimique, peintures lors de leur mise en place, écoulement sanguin, boues dans les forages pétroliers,...) a motivé un grand nombre de travaux expérimentaux plus fondamentaux sur le sujet, particulièrement dans les vingt dernières années. Les résultats correspondants montrent une très grande diversité des

  2. Kommunikative Konstitution von Organisationen

    DEFF Research Database (Denmark)

    Schoeneborn, Dennis; Wehmeier, Stefan

    2014-01-01

    Beiträge zur Unternehmenskommunikation behandeln in der Regel (strategisch) geplante interne oder externe Kommunikation. Der vorliegende Beitrag stellt einen alternativen Theorieansatz vor, der aktuell im nordamerikanischen Forschungsgebiet „Organizational Communication“ vorherrschend ist....... zunehmende Aufmerksamkeit erhält Der sogenannten „CCO-Perspektive“ („Communicative Constitution of Organizations“) zufolge bestehen Unternehmen aus einer Vielzahl von internen und externen Kommunikationspraktiken, die nur in bedingtem Maße strategisch steuerbar sind. Zugleich sind es eben diese...

  3. Kulturelle Aspekte von Textsorten

    Directory of Open Access Journals (Sweden)

    Siegfried Heusinger

    1998-12-01

    Full Text Available Ich fasse meine Überlegungen zu kulturellen Aspekten von Textsorten zusammen: 1. Mit unseren Kulturverständnis ist die terminologisierte Wortgruppe "interkulturelle Kommunikation" nicht zu begreifen als Kommunikation zwischen Menschen verschiedener kultureller Bindungen, sondern sie ist nicht zu begreifen als Kommunikation zwischen Menschen verschiedener kultureller Bindungen, sondern sie ist ethnisch wie auch ethisch angepasstes sprachlichkommunikatives Verhalten an kulturelle Traditionen der jeweils für den Kommunkations- akt vereinbarten Sprache. 2. Das Adjektiv "interkulturell" referiert auf idiomatisierte Wendungen im zwischenmenschlichen Kontakt wie auch auf kulturell gebundene Unterschiede in der Benennungsmotivation (z.B. anloben/österr./, vereidigen /dt./ 3. Das Adjektiv "interkulturell" ist ebenfalls zu beziehen auf den Austausch von Erfahrungen und Ideen, auf den Dialog von Kulturen. 4. Textsorten existieren in ihrer kulturellen in ihrer kulturellen Tradition, wobei das Kulturspezifische vornehmlich in traditionellen (aber entwicklungsoffenen Formulierungs- und Gestaltungsmustern zu suchen iost. Andere Textsortencharakteristika wie die situative Einbettung, die kommunikative Zwecksetzung, die thematische Bindung und die Komposition haben offenbar kaum eine kulturspezifische Prägung. 5. Im Trend zur Internationalisierung der Textsorten erweisen sich die kulturell geprägten Textmustervor allem zwischen angrenzenden Nationen häufig als affin.

  4. Mise en evidence de quelques proteins impliquéees dans les ...

    African Journals Online (AJOL)

    Mise en evidence de quelques proteins impliquéees dans les interactions Dioscorea alata L. Colletotrichum gloeosporioides PENZ : Characterization of some proteins involved in the interaction between Dioscorea alata L. – Colletotrichum gloeosporioides PENZ.

  5. Nutzerorientiertes Management von materiellen und immateriellen Informationsobjekten

    OpenAIRE

    Hübsch, Chris

    2001-01-01

    Schaffung einer stabilen, erweiterbaren und skalierbaren Infrastruktur für die Bereitstellung von Diensten im Umfeld von Bibliotheken und ähnlichen wissensanbietenden Einrichtungen unter Verwendung von XML-RPC und Python.

  6. Mise à l'échelle de la science | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    23 févr. 2018 ... Afin de justifier moralement les décisions concernant la mise à l'échelle, les organisations doivent prendre en considération le risque d'incidence assumé par les personnes ... Ainsi, les méthodes de mesure et d'analyse peuvent être adaptées au besoin tout au long du processus de mise à l'échelle.

  7. Étude des potentialités et contraintes de mise en valeur durable de ...

    African Journals Online (AJOL)

    L'aménagement proposé a consisté à la mise en place des demi-lunes dans la dépression, à l'installation des puits pour irrigation et à l'installation des trous à poissons. Mots clés : Agbobada, plaine inondable, mise en valeur durable, écosystème, aménagement. In order to contribute to the sustainable development of the ...

  8. Mise à l'essai d'interventions visant à influencer les choix ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Elle élaborera également des protocoles pour la mise en oeuvre d'interventions mises à l'essai sur le terrain visant la prise de décision alimentaire des pauvres. Enfin, elle préparera une proposition en vue de réaliser un essai comparatif à grande échelle sur échantillon aléatoire d'une ou de plusieurs interventions qui ...

  9. Influence of the lithosphere-asthenosphere boundary on the stress field northwest of the Alps

    Science.gov (United States)

    Maury, J.; Cornet, F. H.; Cara, M.

    2014-11-01

    In 1356, a magnitude 6-7 earthquake occurred near Basel, in Switzerland. But recent compilations of GPS measurements reveal that measured horizontal deformation rates in northwestern continental Europe are smaller than error bars on the measurements, proving present tectonic activity, if any, is very small in this area. We propose to reconcile these apparently antinomic observations with a mechanical model of the lithosphere that takes into account the geometry of the lithosphere-asthenosphere boundary, assuming that the only loading mechanism is gravity. The lithosphere is considered to be an elastoplastic material satisfying a Von Mises plasticity criterion. The model, which is 400 km long, 360 km wide and 230 km thick, is centred near Belfort in eastern France, with its width oriented parallel to the N145°E direction. It also takes into account the real topography of both the ground surface and that of the Moho discontinuity. Not only does the model reproduce observed principal stress directions orientations, it also identifies a plastic zone that fits roughly the most seismically active domain of the region. Interestingly, a somewhat similar stress map may be produced by considering an elastic lithosphere and an ad-hoc horizontal `tectonic' stress field. However, for the latter model, examination of the plasticity criterion suggests that plastic deformation should have taken place. It is concluded that the present-day stress field in this region is likely controlled by gravity and rheology, rather than by active Alpine tectonics.

  10. Thermal Stress Analysis of W/Cu Functionally Graded Materials by Using Finite Element Method

    Science.gov (United States)

    Yang, Zhenxiao; Liu, Min; Deng, Chunming; Zhang, Xiaofeng; Deng, Changguang

    2013-03-01

    Copper alloys with tungsten coating shows an excellent plasma irradiation resistance, however, the difference of coefficient thermal expansion between W and Cu makes it really a difficult job to prepare over 1 mm W coating with high adhesive strength. Functionally graded material (FGM) seems to be an effective method to improve the adhesive strength of thick W coating. This paper focused on the finite element simulation on thermal stress for W/Cu FGM with different graded layers, composition and thicknesses. In addition, the variance of stresses for functionally graded coatings with the steady state heat flux were simulated by finite element analysis (ANSYS Workbench). The results showed that the W/Cu FGM was effectively beneficial for the stress relief of W coating. Meanwhile, the maximum von mises stress decreased approximately by 52.8 % compared to monolithic W plasma facing material. And the four-layer FGM with a compositional exponent of 2 was optimum for 1.5 mm W coating.

  11. The effect of the sagittal ridge angle on cartilage stress in the equine metacarpo-phalangeal (fetlock) joint.

    Science.gov (United States)

    Liley, Helen; Davies, Helen; Firth, Elwyn; Besier, Thor; Fernandez, Justin

    2017-06-15

    Fatigue failure of bones of the metacarpo-phalangeal (fetlock, MCP) joint is common in thoroughbred racehorses. Stresses within the fetlock joint cartilages are affected by the morphology of the third metacarpal bone (MC3) and proximal phalangeal bone, and the steepness of the median sagittal ridge of MC3 is believed to be associated with fracture. This study investigated the influence of the steepness of the sagittal ridge on cartilage stress distribution using a finite element model of the joint. Changes to the steepness of the sagittal ridge were made by applying a parabolic function to the mesh, creating four different models with sagittal ridge angles ranging from 95° to 105°. In the fetlock joint of Thoroughbred racehorses, sagittal ridge angles of >100° were associated with higher Von Mises stresses in cartilage at the palmar aspect of the condylar groove than such stresses in joints with sagittal ridge angles of fetlock joint thus appears to play an important role in the magnitude and distribution of cartilage stresses, which, when acting on the underlying hard tissues of the articular calcified cartilage and subchondral bone may play a role in the initiation of fatigue fracture in the third metacarpal bone.

  12. A Patient Specific Biomechanical Analysis of Custom Root Analogue Implant Designs on Alveolar Bone Stress: A Finite Element Study

    Directory of Open Access Journals (Sweden)

    David Anssari Moin

    2016-01-01

    Full Text Available Objectives. The aim of this study was to analyse by means of FEA the influence of 5 custom RAI designs on stress distribution of peri-implant bone and to evaluate the impact on microdisplacement for a specific patient case. Materials and Methods. A 3D surface model of a RAI for the upper right canine was constructed from the cone beam computed tomography data of one patient. Subsequently, five (targeted press-fit design modification FE models with five congruent bone models were designed: “Standard,” “Prism,” “Fins,” “Plug,” and “Bulbs,” respectively. Preprocessor software was applied to mesh the models. Two loads were applied: an oblique force (300 N and a vertical force (150 N. Analysis was performed to evaluate stress distributions and deformed contact separation at the peri-implant region. Results. The lowest von Mises stress levels were numerically observed for the Plug design. The lowest levels of contact separation were measured in the Fins model followed by the Bulbs design. Conclusions. Within the limitations of the applied methodology, adding targeted press-fit geometry to the RAI standard design will have a positive effect on stress distribution, lower concentration of bone stress, and will provide a better primary stability for this patient specific case.

  13. [Three dimensional finite element analysis on stress distribution in dentin of the maxillary central incisor restored with different shapes and materials of post].

    Science.gov (United States)

    Zhang, Xuying; Sun, Jing; Lu, Jun

    2012-04-01

    To investigate the stress distribution in dentin of the maxillary central incisor restored with post-core which is related to different shapes and materials. CT scan, digital-image processing and Unigraphics (UG) software were applied to construct the three-dimensional finite element models of maxillary central incisor restored with cone or column post-core. Based on this model, stress distribution of Von Mises in dentin with three different materials(polyethylene fiber resin, carbon fiber and zirconia) were analyzed respectively. Static loading(100N) was used on the lingual boundary line between upper-one-third and middle-one-third of maxillary central incisor, the direction of the loading was 45 degrees to the tooth long axis. In posts made of zirconia and restored with column post, the stress distribution in dentin was higher than with cone post (P0.05). The elastic modulus of post-core materials affected the stress distribution, and the higher the elastic modulus was, the higher the stress concentrated. Cone post excels column post in higher elastic modulus materials. Using the lower elastic modulus materials possibly can avail to the stress distribution and prevent the root breakage. During the root canal preparation, the dentin around the root neck should be conserved as more as possible, especially the dentin in the labial side.

  14. Evaluation of stress patterns on maxillary posterior segment when intruded with mini implant anchorage: A three-dimensional finite element study

    Directory of Open Access Journals (Sweden)

    Nikhita Pekhale

    2016-01-01

    Full Text Available Introduction: The aim of this study is to evaluate stress and displacement effects of maxillary posterior intrusion mechanics with mini-implant anchorage by using finite element method. Materials and Methods: A computer stimulation of three-dimensional model maxilla with all teeth, PDL, bone, mini-implants, brackets, arch wire, force element, and transpalatal arch was constructed on the basis of average anatomic morphology. Finite element analysis was done to evaluate the amount of stress and its distribution during orthodontic intrusive force. Results: Increased Von Mises stress values were observed in mesio-cervical region of first molar. The middle third of second premolar and second molar and regions adjacent to force application sites also showed relatively high stress values. Minimum stress values were observed in apical region of first premolar as it is away from force application. Conclusion: Using three mini-implant and transpalatal arches, this study demonstrates that significant amount of true intrusion of maxillary molars could be obtained with lesser concentration of stresses in the apical area recorded.

  15. Effect of restoration technique on stress distribution in roots with flared canals: an FEA study.

    Science.gov (United States)

    Belli, Sema; Eraslan, Öznur; Eraslan, Oğuz; Eskitaşcıoğlu, Gürcan

    2014-04-01

    The aim of this finite element analysis (FEA) study was to test the effect of different restorative techniques on stress distribution in roots with flared canals. Five three-dimensional (3D) FEA models that simulated a maxillary incisor with excessive structure loss and flared root canals were created and restored with the following techniques/materials: 1) a prefabricated post: 2) one main and two accessory posts; 3) i-TFC post-core (Sun Medical); 4) the thickness of the root was increased by using composite resin and the root was then restored using a prefabricated post; 5) an anatomic post was created by using composite resin and a prefabricated glass-fiber post. Composite cores and ceramic crowns were created. A 300-N static load was applied at the center of the palatal surface of the tooth to calculate stress distributions. SolidWorks/Cosmosworks structural analysis programs were used for FEA analysis. The analysis of the von Mises and tensile stress values revealed that prefabricated post, accessory post, and i-TFC post systems showed similar stress distributions. They all showed high stress areas at the buccal side of the root (3.67 MPa) and in the cervical region of the root (> 3.67 MPa) as well as low stress accumulation within the post space (0 to 1 MPa). The anatomic post kept the stress within its body and directed less stress towards the remaining tooth structure. The creation of an anatomic post may save the remaining tooth structure in roots with flared canals by reducing the stress levels.

  16. Stresses around a miniscrew. 3-D analysis with the finite element method (FEM).

    Science.gov (United States)

    Geramy, Allahyar

    2009-11-01

    Miniscrews used for absolute anchorage may induce stresses in the surrounding tissues that are dependent on their proximity to the miniscrew. To determine the stresses in the buccal walls of the sockets of lower molars adjacent to a miniscrew under load when the position and angulation of the miniscrew are changed. Five 3-D FEM models containing the first and second lower molars, their periodontal ligaments and the surrounding spongy and cortical bone, were modelled in SolidWorks 2006 (SolidWorks, Concord, MA, USA) and transferred to the ANSYS Workbench (ANSYS Inc., Southpointe, Canonsburg, PA, U.S.A.). A tensile force of 2 N, decomposed in 3-D space, was applied to a miniscrew inserted between the lower first and second molars. The von Mises (equivalent) stresses along the buccal walls of the sockets of the first and second molars were derived following changes in miniscrew position and angulation. No direct force was applied to the molars. When the miniscrew was inserted at right angles to the bone and midway between the molars the stress in the crestal area was 0.093 MPa. This stress increased proportionally in the first molar socket as the miniscrew was moved towards the first molar and declined when the miniscrew was tipped towards the second molar. Stresses also decreased in the crestal area of the second molar as the miniscrew was moved towards the first molar, but increased when it was tipped towards the second molar. A 30-55 per cent increase in crestal stress in the first molar socket was detected. Stress occurred in the tissues surrounding a miniscrew subjected to a force vector. Changes in the position or angulation of a miniscrew can affect the stress in the socket walls of adjacent teeth.

  17. Four lateral mass screw fixation techniques in lower cervical spine following laminectomy: a finite element analysis study of stress distribution.

    Science.gov (United States)

    Song, Mingzhi; Zhang, Zhen; Lu, Ming; Zong, Junwei; Dong, Chao; Ma, Kai; Wang, Shouyu

    2014-08-09

    Lateral mass screw fixation (LSF) techniques have been widely used for reconstructing and stabilizing the cervical spine; however, complications may result depending on the choice of surgeon. There are only a few reports related to LSF applications, even though fracture fixation has become a severe complication. This study establishes the three-dimensional finite element model of the lower cervical spine, and compares the stress distribution of the four LSF techniques (Magerl, Roy-Camille, Anderson, and An), following laminectomy -- to explore the risks of rupture after fixation. CT scans were performed on a healthy adult female volunteer, and Digital imaging and communication in medicine (Dicom) data was obtained. Mimics 10.01, Geomagic Studio 12.0, Solidworks 2012, HyperMesh 10.1 and Abaqus 6.12 software programs were used to establish the intact model of the lower cervical spines (C3-C7), a postoperative model after laminectomy, and a reconstructive model after applying the LSF techniques. A compressive preload of 74 N combined with a pure moment of 1.8 Nm was applied to the intact and reconstructive model, simulating normal flexion, extension, lateral bending, and axial rotation. The stress distribution of the four LSF techniques was compared by analyzing the maximum von Mises stress. The three-dimensional finite element model of the intact C3-C7 vertebrae was successfully established. This model consists of 503,911 elements and 93,390 nodes. During flexion, extension, lateral bending, and axial rotation modes, the intact model's angular intersegmental range of motion was in good agreement with the results reported from the literature. The postoperative model after the three-segment laminectomy and the reconstructive model after applying the four LSF techniques were established based on the validated intact model. The stress distribution for the Magerl and Roy-Camille groups were more dispersive, and the maximum von Mises stress levels were lower than the other

  18. High Aspect Ratio Nanoimprint Mold-Cavity Filling and Stress Simulation Based on Finite-Element Analysis

    Directory of Open Access Journals (Sweden)

    Hongwen Sun

    2017-08-01

    Full Text Available High aspect ratio three-dimensional micro- and nanopatterns have important applications in diverse fields. However, fabricating these structures by a nanoimprinting method invites problems like collapse, dislocation, and defects. Finite-element analysis (FEA is a good approach to help understand the filling process and stress distribution. The FEA method was employed to simulate the nanoimprinting process using positive and negative molds with aspect ratios of 1:1, 3:1, 5:1, and 7:1. During the filling process, the resist adjacent to boundaries has the maximum displacement. The corners of contact areas between the protruding part of the mold and the resist has the maximum Von Mises stress. For both positive and negative molds, the maximum stress in the mold increases with aspect ratio. However, filling up negative molds is more difficult than positive ones. With the same aspect ratio, the maximum stress in a negative mold is approximately twice as large as that in a positive one.

  19. John von Neumann Birthday Centennial

    Energy Technology Data Exchange (ETDEWEB)

    Grcar, Joseph F.

    2004-11-12

    In celebration of John von Neumann's 100th birthday, a series of four lectures were presented on the evening of February 10, 2003 during the SIAM Conference on Computational Science and Engineering in San Diego. The venue was appropriate because von Neumann spent much of the later part of his life, in the 1950's, as an unofficial ambassador for computational science. He was then the only senior American scientist who had experience with the new computers (digital, electronic, and programmable) and a vision of their future importance. No doubt he would have relished the chance to attend a meeting such as this. The first speaker, William Aspray, described the ''interesting times'' during which computers were invented. His remarks were based on his history [1] of this period in von Neumann's life. We were honored to have John von Neumann's daughter, Marina von Neumann-Whitman, as our second speaker. Other accounts of von Neumann's life can be found in books by two of his colleagues [2] and [3]. Our third speaker, Peter Lax, provided both mathematical and international perspectives on John von Neumann's career. Finally, Pete Stewart spoke about von Neumann's numerical error analysis [4] in the context of later work; this talk did not lend itself to transcription, but readers may consult the historical notes in [5]. Our thanks to all the speakers for a remarkable evening. We are grateful to the DOE Applied Mathematical Sciences (AMS) program for partially supporting these lectures. Thanks are also due to SIAM and William Kolata, to our emcee, Gene Golub, to Paul Saylor for recording and editing, and to Barbara Lytle for the transcriptions. More about von Neumann's work can be learned from the recent American Mathematical Society proceedings [6].

  20. A novel approach to in vivo mitral valve stress analysis.

    Science.gov (United States)

    Xu, Chun; Brinster, Clay J; Jassar, Arminder S; Vergnat, Mathieu; Eperjesi, Thomas J; Gorman, Robert C; Gorman, Joseph H; Jackson, Benjamin M

    2010-12-01

    Three-dimensional (3-D) echocardiography allows the generation of anatomically correct and time-resolved geometric mitral valve (MV) models. However, as imaged in vivo, the MV assumes its systolic geometric configuration only when loaded. Customarily, finite element analysis (FEA) is used to predict material stress and strain fields rendered by applying a load on an initially unloaded model. Therefore, this study endeavors to provide a framework for the application of in vivo MV geometry and FEA to MV physiology, pathophysiology, and surgical repair. We hypothesize that in vivo MV geometry can be reasonably used as a surrogate for the unloaded valve in computational (FEA) simulations, yielding reasonable and meaningful stress and strain magnitudes and distributions. Three experiments were undertaken to demonstrate that the MV leaflets are relatively nondeformed during systolic loading: 1) leaflet strain in vivo was measured using sonomicrometry in an ovine model, 2) hybrid models of normal human MVs as constructed using transesophageal real-time 3-D echocardiography (rt-3DE) were repeatedly loaded using FEA, and 3) serial rt-3DE images of normal human MVs were used to construct models at end diastole and end isovolumic contraction to detect any deformation during isovolumic contraction. The average linear strain associated with isovolumic contraction was 0.02 ± 0.01, measured in vivo with sonomicrometry. Repeated loading of the hybrid normal human MV demonstrated little change in stress or geometry: peak von Mises stress changed by MV deformed minimally during isovolumic contraction, as measured by the mean absolute difference calculated over the surfaces of both leaflets between serial MV models: 0.53 ± 0.19 mm. FEA modeling of MV models derived from in vivo high-resolution truly 3-D imaging is reasonable and useful for stress prediction in MV pathologies and repairs.

  1. La mise en texte mathématique.

    Directory of Open Access Journals (Sweden)

    Alain Herreman

    2004-04-01

    Full Text Available L’auteur commence par rappeler la diversité d’aspects des textes mathématiques. Il s’appuie pour cela sur plusieurs études historiques récentes consacrées à l’analyse et aux conséquences de cette diversité dans le cas des mathématiques babyloniennes, grecques et chinoises. Il propose ensuite une analyse sémiotique de la transcription de l’un des textes latins par lesquels l’arithmétique fondée sur les chiffres arabes a été diffusée en Occident. La comparaison des résultats obtenus avec ceux de la même analyse appliquée à la traduction française qui a récemment été donnée de ce texte lui permet de comparer l’évolution de la forme des textes mathématiques avec l’évolution des caractéristiques sémiotiques des nombres. Au cours de cet article, il propose un rapprochement entre le type de «mise en texte» adoptée et certains préjugés formalistes.The author starts by reminding the diversity of aspects of mathematical texts. To this purpose, he backs up his theories on several recent historical studies devoted to the analysis and to the consequences of this diversity as for Babylonian, Greek and Chinese mathematics. Then, he proposes a semiotic analysis of one of the Latin texts’ transcription thanks to which the arithmetic based on Arabic ciphers was introduced in the West. The comparison of the results with those of the same analysis applied to the French translation of this text that has just been issued allows him to compare the evolution of the form of mathematical texts to the evolution of the semiotical characteristics of ciphers. In the course of this article, he proposes a connection both between the type of «text setting» and some formalist prejudices.

  2. Stress

    Science.gov (United States)

    ... natural disaster. This type of stress can cause post-traumatic stress disorder (PTSD). Different people may feel stress in different ways. Some people experience digestive symptoms. Others may have headaches, sleeplessness, depressed mood, anger, ...

  3. Influence of tooth preparation design on the stress distribution in maxillary central incisors restored by means of alumina porcelain veneers: a 3D-finite element analysis.

    Science.gov (United States)

    Zarone, Fernando; Apicella, Davide; Sorrentino, Roberto; Ferro, Valeria; Aversa, Raffaella; Apicella, Antonio

    2005-12-01

    The present study aimed at providing 3D-FEA engineering tools for the understanding of the influence of tooth preparation design on the stress distribution and localization of critical sites in maxillary central incisors restored by means of alumina porcelain veneers under functional loading. A 3D-FEM model of a maxillary central incisor is presented. An arbitrary chewing static force of 10 N was applied with an angulation of 60 and 125 degrees to the tooth longitudinal axis at the palatal surface of the crown. The model was considered to be restored by means of alumina porcelain veneers with different tooth preparation designs. The differences in occlusal load transfer ability of the two restorative systems are discussed. The maximum Von Mises equivalent stress values were observed in the window restorative system for both 125 and 60 degrees load angulations. When the chamfer with palatal overlap preparation was simulated, the stress distributed uniformly in the cement layer, whereas in the window preparation the stress mainly occurred in the incisal area of the cement layer. When restoring a tooth by means of porcelain veneers, the chamfer with palatal overlap preparation better restores the natural stress distribution under load than the window technique.

  4. Stress analysis of endodontically treated teeth restored with post-retained crowns: A finite element analysis study.

    Science.gov (United States)

    Al-Omiri, Mahmoud Khaled; Rayyan, Mohammad Ramadan; Abu-Hammad, Osama

    2011-03-01

    The authors conducted a study to analyze the stress concentration areas in a tooth restored with a post-retained crown under various conditions. The authors constructed a three-dimensional finite element model describing a maxillary second premolar restored with an all-ceramic crown supported by a titanium post and a resin-based composite core. They applied static vertical and horizontal loads of 100 newton to the cusp tip of the crown and recorded Von Mises and tensile stress values. The variables investigated were the presence of the post, coronal and apical post extensions, post diameter, post shape, and post and core material. The study results showed that horizontal loading generated higher levels of stress than did vertical loading. The greatest stress levels were concentrated at the cervical region and at the post-dentin interface in all models. Under both loads, a higher modulus of elasticity of the post material and a wider post diameter were associated with increased stress values at the post-dentin interface. Reduction of the post extension above the level of bone was associated with increased dentinal stresses near the apex of the post. Although endodontic posts provide retention for coronal restorations, they result in dentinal stress values higher than those of crowns without posts. Posts that had a similar modulus of elasticity to dentin and smaller diameters were associated with better stress distribution. Resting coronal restorations on sound dental tissues affected stress distribution more than did the core material or the length of the coronal post extension. Many factors influence the distribution of stress within dentin and, consequently, the fracture resistance of teeth restored with post-retained crowns. Clinicians need to keep these factors in mind when performing endodontic procedures that involve placement of post-retained crowns to ensure optimal success.

  5. Evaluation of stress distributions occurring on zirconia and titanium implant-supported prostheses: A three-dimensional finite element analysis.

    Science.gov (United States)

    Bankoğlu Güngör, Merve; Yılmaz, Handan

    2016-09-01

    Titanium implants have been successfully used to support fixed dental prostheses. Zirconia implants have been suggested as support for crowns, but information on their use to support partial fixed dental prostheses is limited. The purpose of this finite element study was to evaluate the maximum principal, minimum principal, and von Mises stresses and their distributions on zirconia and titanium implant-supported, partial fixed dental prostheses located in the anterior maxillary region. Zirconia and titanium implants (4 mm in diameter and 11. 5 mm in length) and prostheses made from 2 different materials (lithium disilicate and zirconia) were simulated, and 4 models were generated: Titan-IPS, Titan-Lava, Zircon-IPS, and Zircon-Lava. The maxillary bone was modeled as type 3 bone. The load was applied obliquely (534 N) and horizontally (76.5 N), and the stress values and distributions were examined. Under horizontal loading, stresses generated on the cortical bone in the Zircon models were lower than those in the Titan models. Under oblique loading, stress values were similar in the same implant material and stress type. For all types of stress among the models, the stress values that occurred on the trabecular bone were found to be similar under both horizontal and oblique loading. The maximum stress values on the bones, implants, cores, and veneers did not exceed the strength of the structures. Different stress values resulted from the different implant types. The prosthetic materials did not change the stress distributions in bone. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  6. Influence of different post design and composition on stress distribution in maxillary central incisor: Finite element analysis

    Directory of Open Access Journals (Sweden)

    Silva Natercia

    2009-01-01

    Full Text Available Background: Post design and material has very important effects on dentinal stress distribution since the post placement can create stresses that lead to root fracture. Materials and Methods: In this study we use finite element analysis (FEA to evaluate stress distribution on endodontically treated maxillary central incisors that have been restored with different prefabricated posts. Six models were generated from the image of anatomical plate: Four metallic posts (ParaPost XH, ParaPost XT, ParaPost XP, and Flexi-Flange and one fiberglass post (ParaPost Fiber Lux. The sixth model was a control-a sound maxillary central incisor. We used CAD software and exported the models to ANSYS 9.0. All the materials and structures were considered elastic, isotropic, homogeneous, and linear except the fiberglass post which was considered orthotropic. The values for the mechanical properties were obtained by a review of the literature and the model was meshed with 8-node tetrahedral elements. A load of 2N was applied to the lingual surface at an angle of 135°. Results: The stress results were recorded by shear stress and von Mises criteria; it was observed that there was no difference for stress distribution among the titanium posts in the radicular portions and into posts. There was higher stress concentration on the coronary portion with the titanium posts than with the glass fiber post. It seems that the metallic posts′ external configuration does not influence the stress distribution. Conclusion: Fiber posts show more homogeneous stress distribution than metallic posts. The post material seems to be more relevant for the stress distribution in endodontically treated teeth than the posts′ external configuration.

  7. Alejandro Von Humboldt

    Directory of Open Access Journals (Sweden)

    Gerardo Paz Otero

    1965-09-01

    Full Text Available Diverso fue y sigue siéndolo, el destino de los dos hermanos Humboldt, Guillermo y Alejandro. Sino que se inicia con el nacimiento: Guillermo, el mayor, nace el 22 de junio de 1767 en Potsdam, residencia de los emperadores prusianos, la ciudad de los palacios imperiales, el imperio del militarismo germano; su cuna se meció cerca al palacete de Sans-Soussi, donde Federico el Grande forja ba el poderío de Prusia, cultivaba las ciencias y las artes, anfitrionaba a los intelectuales de Europa, y era "vasallo espiritual de Volta ire", según la aguda frase de Goethe. Alejandro viene al mundo dos años después (14 de septiembre de 1769 en Berlín, en la casa burguesa de la Jagerstrasse (calle del cazador que su madre Elizabeth von Humboldt heredara de su primer esposo.

  8. Der Einfluss von Phlorizin auf den programmierten Zelltod von Erythrozyten

    OpenAIRE

    Meier, Anja Doris

    2013-01-01

    Erythrozyten sind in der Lage, suizidalen Zelltod zu betreiben. Von einigen Substanzen ist bereits bekannt, dass sie die sogenannte Eryptose beeinflussen. Beispiele dafür sind Quecksilber, Monensin, Benzethonium und Oridonin, welche zu den Stimulatoren der Eryptose gehören. Blebbistatin, Koffein und Endothelin, gehören zu den Inhibitoren. In dieser Studie sollte untersucht werden, welchen Einfluss Phlorizin auf den Ablauf des suizidalen Zelltodes von Erythrozyten hat. Es wurde belegt, dass si...

  9. Biographical sketch: Georg Hermann von Meyer (1815-1892).

    Science.gov (United States)

    Skedros, John G; Brand, Richard A

    2011-11-01

    This biographical sketch on Georg Hermann von Meyer highlights the interactions in the 1860s that von Meyer, a famous anatomist, had with Karl Culmann, a famous structural engineer and mathematician. The published papers from this interaction caught the attention of Julius Wolff and stimulated his development of the trajectorial hypothesis of bone adaptation--now called "Wolff's Law." The corresponding translations are provided: (1) von Meyer's 1867 paper that highlights the regularity of arched trabecular patterns in various human bones, and his discussions with Culmann about their possible mechanical relevance; and (2) Wolff's 1869 paper that first mentions the correspondence of stress trajectories in a solid, crane-like structure to the arched trabecular patterns in the proximal human femur. This biographical sketch on Georg Hermann von Meyer corresponds to the historic texts, The Classic: The Architecture of the Trabecular bone (by von Meyer), and The Classic: On the Significance of the Architecture of the Spongy Substance for the Question of Bone Growth. A preliminary publication (by Wolff) available at DOIs 10.1007/s11999-011-2041-5 , 10.1007/s11999-011-2042-4 .

  10. Effect of different restorative crown and customized abutment materials on stress distribution in single implants and peripheral bone: A three-dimensional finite element analysis study.

    Science.gov (United States)

    Kaleli, Necati; Sarac, Duygu; Külünk, Safak; Öztürk, Özgür

    2017-06-20

    In recent years, the use of resin-matrix ceramics and polyetheretherketone (PEEK) abutments has been suggested to absorb excessive stresses on dental implants. However, only a few studies have evaluated the effect of these materials on stress distribution in implants and peripheral bone structure. The purpose of this finite element analysis was to evaluate the biomechanical behaviors of resin-matrix ceramics and PEEK customized abutments in terms of stress distribution in implants and peripheral bone. Three-dimensional (3D) models of a bone-level implant system and a titanium base abutment were created by using the standard tessellation language (STL) data of original implant components. An anatomic customized abutment and a maxillary right second premolar crown were then modeled over the titanium base abutment. A bone block representing the maxillary right premolar area was created, and the implant was placed in the bone block with 100% osseointegration. Six different models were created according to combinations of restoration materials (translucent zirconia [TZI], lithium disilicate glass ceramic [IPS], polymer-infiltrated hybrid ceramic [VTE]), and customized abutment materials (PEEK and zirconia). In each model, the implants were loaded vertically (200 N) and obliquely (100 N). The stress distribution in the crown, implant, and abutments was evaluated through the von Mises stress analysis, and the stress distribution in the peripheral bone was examined through the maximum and minimum principal stress analyses. The oblique load resulted in high stress values in the implant components, restorative crown, and cortical bone. Low stress values were observed in the VTE crowns. Zirconia customized abutments exhibited higher stress values than PEEK customized abutments. The stress distributions in the implant and peripheral bone were similar in all models. Changes in restoration and customized abutment material did not affect stress distribution in the implant and

  11. Surface mechanical property and residual stress of peened nickel-aluminum bronze determined by in-situ X-ray diffraction

    Science.gov (United States)

    Wang, Chengxi; Jiang, Chuanhai; Zhao, Yuantao; Chen, Ming; Ji, Vincent

    2017-10-01

    As one of the most important surface strengthening method, shot peening is widely used to improve the fatigue and stress corrosion crack resistance of components by introducing the refined microstructure and compressive residual stress in the surface layer. However, the mechanical properties of this thin layer are different from the base metal and are difficult to be characterized by conventional techniques. In this work, a micro uniaxial tensile tester equipped with in-situ X-ray stress analyzer was employed to make it achievable on a nickel-aluminum bronze with shot peening treatment. According to the equivalent stress-strain relationship based on Von Mises stress criterion, the Young's modulus and yield strength of the peened layer were calculated. The results showed that the Young's modulus was the same as the bulk material, and the yield strength corresponding to the permanent plastic strain of 0.2% was increased by 21% after SP. But the fractographic analysis showed that the fracture feature of the surface layer was likely to transform from the dimple to the cleavage, indicating the improved strength might be attained at the expense of ductility. The monotonic and cyclic loading were also performed via the same combined set-up. In addition, the specific relaxation behavior of compressive residual stress was quantified by linear logarithm relationship between residual stress and cycle numbers. It was found that the compressive residual stress mainly relaxed in the first few cycles, and then reached steady state with further cycles. The relaxation rate and the stable value were chiefly depended on the stress amplitude and number of cycles. The retained residual stress kept in compressive under all given applied stress levels, suggesting that the shot peening could introduce a more stable surface layer of compressive residual stress other than the elevated strength of nickel-aluminum bronze alloy.

  12. Mise au point d'un reacteur epitaxial CBE

    Science.gov (United States)

    Pelletier, Hubert

    Ce projet de maîtrise consiste à l'asservissement et la mise en marche d'un réacteur d'épi-taxie par jets chimiques au Laboratoire d'Épitaxie Avancée de l'Université de Sherbrooke. Le réacteur sert à la croissance dans l'ultravide de matériaux semi-conducteurs tels que l'arséniure de gallium (GaAs) et le phosphure d'indium-gallium (GaInP). La programmation LabVIEW™ et du matériel informatique de National Instruments sont utilisés pour asservir le réacteur. Le contrôle de la température de l'échantillon et de la pression de contrôle des réactifs de croissance dans le réacteur est assuré par des boucles de rétroaction. Ainsi, la température de l'échantillon est stabilisée à ±0, 4 °C, alors que les pressions de contrôle de gaz peuvent être modulées sur un ordre de grandeur en 2 à 4 secondes, et stabilisées à ±0, 002 Torr. Le système de pompage du réacteur a été amélioré suite à des mesures de vitesse de pompage d'une pompe cryogénique. Ces mesures révèlent une dégradation sur plus d'un ordre de grandeur de son pompage d'hydrogène avec l'opération à long terme. Le remplacement de la pompe cryogénique par une pompe turbo-moléculaire comme pompe principale a permis d'améliorer la fiabilité du système de pompage du système sous vide. D'autre part, la conductance du système d'acheminement de gaz et d'injection a été augmentée afin de réduire un effet mémoire des sources le système et faciliter la croissance de matériaux ternaires. Ainsi, des croissances de GaAs (100) sur substrat de même nature ont été effectuées et ont révélé un matériau de bonne qualité. Sa rugosité moyenne de 0,17 nm, mesurée par microscopie à force atomique, est très faible selon la littérature. De plus, une mobilité élevée des porteurs est obtenue à fort dopage au silicium, au tellure et au carbone, notamment une mobilité de 42 ± 9 cm2V -1s-1 des porteurs majoritaires '(trous) lors du dopage au carbone à 1, 5 · 1019

  13. Einsatz von Nickel-Katalysatoren zum Cracken von Teerprodukten aus der Niederdruckaufkohlung von Stahl mit Ethin

    OpenAIRE

    Mbadinga Mouanda, Gelase

    2009-01-01

    Die Niederdruckaufkohlung von Stahl ist ein modernes Verfahren, das zur Einsatzhärtung von Stahlbauteilen dient. Bei Temperaturen zwischen 900 und 1050 °C und Drücken unter 50 mbar werden Bauteile durch heterogene Pyrolyse von Ethin in einem Ofen einsatzgehärtet. Das während der Pyrolyse erzeugte Abgas enthält aromatische Kohlenwasserstoffe und kann katalytisch behandelt werden. Der Katalysator wird durch Rußablagerung desaktiviert und muss zyklisch durch Verbrennung mit Luft regeneriert werd...

  14. Applikation von fermentierter Soja bei Krebspatienten zur Verminderung von Kachexie und Erhöhung der Apoptose - eine prospektive Pilotstudie

    Directory of Open Access Journals (Sweden)

    Jacob U

    2009-01-01

    Full Text Available Kachexie ist eine Begleiterkrankung von Krebs, Aids oder rheumatoider Arthritis. Andere Symptome dieser Erkrankungen sind Depression sowie chronische Erschöpfung. Für alle diese Begleiterkrankungen, die die Lebensqualität der schwererkrankten Patienten negativ beeinflussen, wird eine Erhöhung von Entzündungsmediatoren (z.B. IL-6 und TNF-α verantwortlich gemacht. Für Krebs wird eine Erniedrigung der Apoptose, ausgelöst durch eine Erhöhung von NFκB verantwortlich gemacht. Eine Gabe eines fermentierten Soja-Produktes, das in den USA seit 10 Jahren zur Verbesserung der Lebensqualität von Krebspatienten eingesetzt wird, wurde in einer prospektiven Studie untersucht: Für je 5 Patienten, die unter Prostata-, Ovar- oder Brustkrebs litten, konnte eine signifikante Verminderung von Kachexie, Stress und Depression festgestellt werden. Gleichzeitig konnte man für Prostata- und Ovarkrebs-Patienten eine Erhöhung der Genexpression apoptotischer Marker disseminierter Tumorzellen feststellen. Zusätzlich wurde eine starke Erhöhung der Genexpression des Tumorsuppressorgens p21 festgestellt. Auch wenn die prospektive Studie präliminär ist und die Anzahl der untersuchten Patienten zu klein, so widerspricht sie nicht unserer Annahme, dass es einen direkten Zusammenhang zwischen Krebs und Begleiterkrankungen, besonders der Kachexie, gibt.

  15. Living with von Willebrand Disease

    Science.gov (United States)

    ... the condition. For example, the school nurse, teacher, daycare provider, coach, or any leader of afterschool activities ... MedlinePlus) Von Willebrand Disease (MedlinePlus) Building 31 31 Center Drive Bethesda, MD 20892 Learn more about getting ...

  16. Ueber einige Coelenterata von Australien

    NARCIS (Netherlands)

    Stiasny, G.

    1931-01-01

    I. Hydromedusen. *Olindias singularis Browne. II. Scyphomedusen. *Atolla wyvillei Haeckel. *Linuche unguiculata O. Swartz. Pelagia noctiluca Péron u. Lesueur. Cyanea capillata var. annaskala von Lendenfeld. Netrostoma coerulescens Maas. *Versura anadyomene (Maas) Mayer. Catostylus mosaicus L.

  17. Kleben von Kunststoff mit Metall

    CERN Document Server

    Brockmann, W; Käufer, H

    1989-01-01

    Das Buch behandelt das Kleben von Kunststoffen mit Metallen in einer fur den Praktiker verstandlichen und umsetzbaren Form. Es leitet zu Klebeverfahren an, die optimale Ergebnisse hinsichtlich Qualitat, Dauerhaftigkeit und Wirtschaftlichkeit liefern.

  18. Fluorido-Komplexe von Technetium

    OpenAIRE

    Mariappan Balasekaran, Samundeeswari

    2013-01-01

    Zusammenfassung Diese Dissertationsschrift befasst sich mit der Synthese und Charakterisierung neuer Technetiumfluoride mit dem Metall in den Oxidationsstufen “+1”, “+2”, “+4” und “+6”. Im ersten Kapitel wird über die Isolierung von unterschiedlichen Salzen von Fluoridonitridotechnetaten(VI) entweder aus Nitridotechnetium(VI)-säure oder aus Pertechnetat durch den Einsatz geeigneter Reduktionsmittel berichtet. Das Cäsiumsalz dieser Verbindung bildet einen oxido-verbrückten, dimeren Kompl...

  19. Effiziente chemoenzymatische Synthese von dhydroartemisinaldehyd

    OpenAIRE

    Demiray, Melodi; Tang, Xiaoping; Wirth, Thomas; Faraldos, Juan A.; Allemann, Rudolf K.

    2017-01-01

    Artemisinin aus der Pflanze Artemisia annua ist das wirkungsvollste Arzneimittel zur Behandlung von Malaria. Die Sesquiterpen-Cyclase Amorphadien-Synthase, ein Cytochrom-abhängiges CYP450 und eine Aldehyd-Reduktase wandeln in der Pflanze Farnesyl-Diphosphat (FDP) in Dihydroartemisinaldehyd (DHAAl) um, welches ein Schlüsselzwischenprodukt in der Biosynthese von Artemisinin und eine halbsynthetische Vorstufe in der chemischen Synthese des Arzneimittels ist. Hier berichten wir über einen chemoen...

  20. Postulated incipient crack behaviour in pressurized components and examination of fracture toughness and pre-stressed crack tip behaviour under loads induced by emergency cooling of the components; Werkstoffmechanisches Verhalten von postulierten Anrissen in druckfuehrenden Komponenten mit vorbeanspruchter Rissspitze bei Belastung infolge rascher Abkuehlvorgaenge

    Energy Technology Data Exchange (ETDEWEB)

    Klingbeil, D.; Arndt, S.; Haecker, R.; Huenecke, J.; Reusch, F.

    2000-07-01

    A component containing a sharp crack, mechanically loaded in the upper shelf, will not show brittle fracture after cooling into the temperature range of the lower shelf. The fracture toughness of such components after cooling remains higher than the crack resistance determined for this temperature following the specified standard procedures. This apparent increase of the fracture toughness K{sub IC}, known as the warm-pre-stress-effect (WPS-effect), is of practical importance to prove the exclusion of crack initiation in such components in an emergency cooling situation of components. The two major objectives of this research project are first of all the development of a numerical method for quantitative evaluation of pre-cracked specimen or components after warm-pre-stressing, and second in performing an extensive testing program, complementary to the numerical modelling, to investigate the influence of the constraint at the crack tip and the type of pre-loading. The development of the above mentioned numerical method consists of the combination and advancement of existing material modelling techniques in order to describe important influences on the WPS-effect, like blunting, change of crack opening stress distributions, development of residual stresses and plastic deformation. (orig.) [German] Wird ein rissbehaftetes Bauteil im Temperaturbereich der Hochlage durch aeussere Lasten beansprucht, so erfolgt bis zu dieser Belastung auch bei Abkuehlung in den Bereich der Tieflage kein Versagen durch Spaltbruch. Die nach Abkuehlung ermittelte Bruchzaehigkeit ist hoeher als der fuer diese Temperatur normgemaess bestimmte Werkstoffkennwert. Diese, als Warmvorbelastungseffekt (Warm-Pre-Stress-, WPS-Effekt) bezeichnete formale Erhoehung der Bruchzaehigkeit K{sub IC}, ist von grosser praktischer Bedeutung fuer den Nachweis, dass unter Notkuehlbedingungen keine Rissintiierung in Komponenten auftritt. Die beiden Schwerpunkte dieses Forschungsvorhabens liegen in der

  1. Stress distribution inside bone after suture anchor insertion: simulation using a three-dimensional finite element method.

    Science.gov (United States)

    Sano, Hirotaka; Takahashi, Atsushi; Chiba, Daisuke; Hatta, Taku; Yamamoto, Nobuyuki; Itoi, Eiji

    2013-08-01

    To define stress distribution patterns inside a bone around suture anchors inserted at different angles using a three-dimensional finite element (FE) method. An isotropic cube model (Young's modulus, 1,380 MPa; Poisson's ratio, 0.3) was designed on a computer to standardize analysis conditions. A virtual Twinfix anchor was inserted into the cube at two different angles (45° and 90°) against the top surface. A traction force (100 N) was applied to the anchor at six different angles (15°, 30°, 45°, 60°, 75° and 90°) against the top surface. Elastic analysis was performed, and the distribution of the von Mises equivalent stress inside the cube was calculated. The highest value of the equivalent stress at each traction angle was compared between the 45° and 90° anchor insertion settings. Stress concentration was most evident around proximal anchor threads, particularly on the traction side. Interestingly, stress gradually declined with an increase in traction angle only for the 90° insertion setting. At 15° and 90° traction angles, the equivalent stress was lower for the 45° insertion setting than for the 90° insertion setting. In contrast, the 90° insertion setting exhibited lower equivalent stress than the 45° insertion setting at 30°, 45° and 60° traction angles. Insertion of an anchor at 90° might reduce the stress concentration around the proximal anchor threads on the traction side and provide lower equivalent stress in the middle range of traction angles (30°-60°) than insertion at 45°. This could avoid early postoperative anchor failure.

  2. GFRP life in wind rotor blades; Lebensdauer von GFK im Holmgurt und im Schubsteg von Rotorblaettern

    Energy Technology Data Exchange (ETDEWEB)

    Kensche, C.W. [Deutsche Forschungsanstalt fuer Luft- und Raumfahrt e.V. (DLR), Stuttgart (Germany). Inst. fuer Bauweisen- und Konstruktionsforschung

    1999-07-01

    Lives of GFRP rotor blade components were calculated on the basis of Woehler curves and the wind power specific standard WISPERX using the linear Palmgren-Miner rule. The Calculations were based on experiments with belts made of the L20/SL epoxy resin system at pressure ratios R=0.1, and -1 and with torsionally stressed GFRP tubes of linen tissue with the epoxy resing GE162/C260 at R=0.1 and -1. The results were incorporated into Haigh diagrams, from which the damage from the collective load was calculated by linear interpolation of the averaged stresses and amplitudes resp. the lines of constant life. The life curves calculated for different maximum stress horizons are in good agreement with experimental collective loads. A comparison of life curves showed that the linen tissue material was more fatigue-sensitive than the belt material. [German] Fuer GFK-Gurte und Schubstege von Rotorblaettern wurden Lebensdauerberechnungen auf der Basis von Woehlerkurven und dem windenergiespezifischen Standard WISPERX unter Anwendung der linearen Palmgren-Miner Regel durchgefuehrt. Bei der Betrachtung der Gurte wurde auf Versuche an UD-Proben mit dem Epoxidharzsystem L20/SL zurueckgegriffen, die bei Spannungsverhaeltnissen von R=0.1, -1 und 10 durchgefuehrt worden waren. Grundlage fuer die Lebensdauerbestimmung der Schubstege waren Ermuedungsversuche an torsionsbelasteten GFK-Rohren aus Leinengewebe mit dem Epoxidharz GE162/C260 bei R=0.1 und -1. In den daraus konstruierten Haighdiagrammen wurden die Schaedigungen durch das Lastkollektiv mittels linearer Interpolation der Mittelspannungen und Amplituden bzw. der Linien konstanter Lebensdauer ermittelt. Die Lebensdauerkurven, die fuer verschiedene Maximalspannungshorizonte ermittelt wurden, stimmen gut mit experimentellen Lastkollektivergebnissen ueberein. Beim Vergleich der Lebensdauerkurven zeigt sich, dass ein Leinengewebesteg erheblich ermuedungsgefaehrdeter ist als ein Gurt. (orig.)

  3. A Further Finite Element Stress Analysis of Angled Abutments for an Implant Placed in the Anterior Maxilla

    Directory of Open Access Journals (Sweden)

    Dong Wu

    2015-01-01

    Full Text Available To systematically measure and compare the stress distribution on the bone around an implant in the anterior maxilla using angled abutments by means of finite element analysis, three-dimensional finite element simplified patient-specific models and simplified models were created and analyzed. Systematically varied angled abutments were simulated, with angulation ranging from 0° to 60°. The materials in the current study were assumed to be homogenous, linearly elastic, and isotropic. Force of 100 N was applied to the central node on the top surface of the abutments to simulate the occlusal force. To simulate axial and oblique loading, the angle of loading was 0°, 15°, and 20° to the long axis of implant, respectively. There was the strong resemblance between the response curves for simplified patient-specific models and simplified models. Response curves under oblique loading were similar in both models. With abutments angulation increased, maximum von Mises stress firstly decreased to minimum point and then gradually increased to higher level. From a biomechanical point of view, favorable peri-implant stress levels could be induced by angled abutments under oblique loading if suitable angulation of abutments was selected.

  4. Influence of Implant Position on Stress Distribution in Implant-Assisted Distal Extension Removable Partial Dentures: A 3D Finite Element Analysis.

    Directory of Open Access Journals (Sweden)

    Yeganeh Memari

    2014-10-01

    Full Text Available Distal extension removable partial denture is a prosthesis with lack of distal dental support with a 13-fold difference in resiliency between the mucosa and the periodontal ligament, resulting in leverage during compression forces. It may be potentially destructive to the abutments and the surrounding tissues. The aim of this study was to assess the effect of implant location on stress distribution, in distal extension implant assisted removable partial dentures.Three-dimensional models of a bilateral distal extension partially edentulous mandible containing anterior teeth and first premolar in both sides of the arch, a partial removable denture and an implant (4×10mm were designed. With the aid of the finite element program ANSYS 8.0, the models were meshed and strictly vertical forces of 10 N were applied to each cusp tip. Displacement and von Mises Maps were plotted for visualization of results.When an implant was placed in the second premolar region, the highest stress on implant, abutment tooth and cancellous bone was shown. The lowest stress was shown on implant and bone in the 1(st molar area.Implants located in the first molar area showed the least distribution of stresses in the analyzed models.

  5. Modelling evaluation of the testing condition influence on the maximum stress induced in a hip prosthesis during ISO 7206 fatigue testing.

    Science.gov (United States)

    Raimondi, M T; Pietrabissa, R

    1999-06-01

    In vivo fatigue failure of hip prosthesis stems has been extensively reported in literature. The ISO 7206 international standard has been developed to assess the fatigue reliability of hip prostheses. It describes the fatigue testing apparatus and procedure and it is currently adopted by several testing laboratories throughout the world. In this work we evaluate the maximum stress in a titanium alloy commercial stem in different testing conditions, ranging within the standard specification, using the finite element method applied to a 3D model of the stem. The calculated maximum von Mises stress ranges from +4.5 to -1.5% (for different cement constraint levels) and from +6.7 to -6.8% (for different stem angular orientations) with respect to that calculated at the nominal testing conditions. The results suggest that the ISO 7206 testing specification will give experimental data of reasonable accuracy, with probably no more scatter than that found in typical specimen test results. This is particularly important in the case of components manufactured from materials showing a fatigue resistance highly sensitive to stress variations, such as the Ti6A14V alloy, for which a small increase of the maximum applied stress corresponds to a significant decrease of the statistical fatigue life.

  6. Influence of Implant Position on Stress Distribution in Implant-Assisted Distal Extension Removable Partial Dentures: A 3D Finite Element Analysis.

    Science.gov (United States)

    Memari, Yeganeh; Geramy, Allahyar; Fayaz, Amir; Rezvani Habib Abadi, Shirin; Mansouri, Yasaman

    2014-09-01

    Distal extension removable partial denture is a prosthesis with lack of distal dental support with a 13-fold difference in resiliency between the mucosa and the periodontal ligament, resulting in leverage during compression forces. It may be potentially destructive to the abutments and the surrounding tissues. The aim of this study was to assess the effect of implant location on stress distribution, in distal extension implant assisted removable partial dentures. Three-dimensional models of a bilateral distal extension partially edentulous mandible containing anterior teeth and first premolar in both sides of the arch, a partial removable denture and an implant (4×10mm) were designed. With the aid of the finite element program ANSYS 8.0, the models were meshed and strictly vertical forces of 10 N were applied to each cusp tip. Displacement and von Mises Maps were plotted for visualization of results. When an implant was placed in the second premolar region, the highest stress on implant, abutment tooth and cancellous bone was shown. The lowest stress was shown on implant and bone in the 1(st) molar area. Implants located in the first molar area showed the least distribution of stresses in the analyzed models.

  7. Mise en oeuvre de la Convention-cadre pour la lutte antitabac au ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    SEATCA) de coordonner un programme de recherche pour appuyer la mise en oeuvre (dans le cas du Cambodge) et la ratification (dans le cas du Laos) de la Convention-cadre pour la lutte antitabac (CCLAT) de l'Organisation mondiale de la santé.

  8. La mise à l'échelle de la science | CRDI - Centre de recherches pour ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    identification et l'essai d'idées et d'innovations évolutives, comme le démontre le premier objectif du plan stratégique du Centre. Dans cette optique, nous cherchons à mieux comprendre comment la mise en oeuvre de projets de ...

  9. Effect of Integration Patterns Around Implant Neck on Stress Distribution in Peri-Implant Bone: A Finite Element Analysis.

    Science.gov (United States)

    Han, Jingyun; Sun, Yuchun; Wang, Chao

    2017-08-01

    To investigate the biomechanical performance of different osseointegration patterns between cortical bone and implants using finite element analysis. Fifteen finite element models were constructed of the mandibular fixed prosthesis supported by implants. Masticatory loads (200 N axial, 100 N oblique, 40 N horizontal) were applied. The cortical bone/implant interface was divided equally into four layers: upper, upper-middle, lower-middle, and lower. The bone stress and implant displacement were calculated for 5 degrees of uniform integration (0, 20%, 40%, 60%, and 100%) and 10 integration patterns. The stress was concentrated in the bone margin and gradually decreased as osseointegration progressed, when the integrated and nonintegrated areas were alternated on the bone-implant surface. Compared with full integration, the integration of only the lower-middle layer or lower half layers significantly decreased von Mises, tensile, and compressive stresses in cortical bone under oblique and horizontal loads, and these patterns did not induce higher stress in the cancellous bone. For the integration of only the upper or upper-middle layer, stress in the cortical and cancellous bones significantly increased and was considerably higher than in the case of nonintegration. In addition, the maximum stress in the cortical bone was sensitive to the quantity of integrated nodes at the bone margin; lower quantity was associated with higher stress. There was no significant difference in the displacement of implants among 15 models. Integration patterns of cortical bone significantly affect stress distribution in peri-implant bone. The integration of only the lower-middle or lower half layers helps to increase the load-bearing capacity of peri-implant bone and decrease the risk of overloading, while upper integration may further increase the risk of bone resorption. © 2016 by the American College of Prosthodontists.

  10. Die Wertigkeit von Bildinformationskategorien und ihre Rolle bei der Beurteilung von Bildern als Medien

    OpenAIRE

    Wieczorek, Ulrich

    1997-01-01

    Die Wertigkeit von Bildinformationskategorien und ihre Rolle bei der Beurteilung von Bildern als Medien. - In: Die Geographiedidaktik ist tot, es lebe die Geographiedidaktik : Festschr. zur Emeritierung von Josef Birkenhauer / hrsg. von Friedhelm Frank ... - München, 1997. - S. 253-271. - (Münchner Studien zur Didaktik der Geographie ; 8)

  11. Ethnographische Filme und die Darstellung von Frauen

    Directory of Open Access Journals (Sweden)

    Judith Keilbach

    2002-03-01

    Full Text Available In dieser Filmographie werden ethnographische und koloniale Filme aus dem Bestand des Nederlands Filmmuseum kommentiert, die für die Frage nach der Darstellung von Frauen und Geschlechterverhältnissen von Interesse sind.

  12. Finite element analysis of stresses in endodontically treated, dowel-restored teeth.

    Science.gov (United States)

    Asmussen, Erik; Peutzfeldt, Anne; Sahafi, Alireza

    2005-10-01

    Endodontically-treated, dowel-restored teeth may experience fracture, but investigations of variables related to fracture are often inconclusive and occasionally contradictory. The finite element method was used to analyze the stresses in dowel-restored teeth. The variables studied were material, shape, bonding, modulus of elasticity, diameter, and length of the dowel. The model of the dowel-restored tooth involved dentin, ligament, cortical and trabecular bone, gingiva, and gutta-percha. The dowels were made of glass fiber, titanium, or zirconia and modeled as an approximation of the brands ParaPost Fiber White, ParaPost XH, and Cerapost, respectively. The dowel was cemented with zinc-phosphate cement or with bonded or nonbonded resin luting agents, and an approximation of the material properties of these 2 materials were used in the modeling. The restoration included a composite resin core and a gold crown. Other variables included taper versus parallel-sided posts, modulus of elasticity, diameter, and length of post. The model was axisymmetrical in 3 dimensions. A load of 100 N was applied to the crown at an angle of 45 degrees, and tensile, shear, and von Mises stresses were calculated. The generated stresses decreased with respect to the dowel material in the following order: glass fiber, titanium, and zirconia. Stresses were in general higher with tapered than with parallel-sided dowels. Stresses were reduced by bonding and with an increasing modulus of elasticity, increasing diameter, and increasing length of the dowel. Within the limitations of this study, it was found that all investigated dowel-related factors influenced the stress field generated in dowel-restored teeth.

  13. John von Neumann selected letters

    CERN Document Server

    2005-01-01

    John von Neuman was perhaps the most influential mathematician of the twentieth century, especially if his broad influence outside mathematics is included. Not only did he contribute to almost all branches of mathematics and created new fields, but he also changed post-World War II history with his work on the design of computers and with being a sought-after technical advisor to many figures in the U.S. military-political establishment in the 1940s and 1950s. The present volume is the first substantial collection of (previously mainly unpublished) letters written by von Neumann to colleagues, friends, government officials, and others. The letters give us a glimpse of the thinking of John von Neumann about mathematics, physics, computer science, science management, education, consulting, politics, and war. Readers of quite diverse backgrounds will find much of interest in this fascinating first-hand look at one of the towering figures of twentieth century science.

  14. An Invitation from Lars von Trier

    DEFF Research Database (Denmark)

    Skadhauge, Troels; Tønder, Lars

    2015-01-01

    Translation of Martin Krasnik interview with Lars von Trier broadcast on DR2, January 12, 2015. The following is an interview of Lars von Trier (LvT) by the Danish journalist Martin Krasnik (MK). The interview took place in Lars von Trier’s home in Brede, a small town just outside Copenhagen...

  15. Management von Anforderungsdokumenten mittels semantischer Wikis

    OpenAIRE

    Decker, B.

    2005-01-01

    Im Projekt RISE wird untersucht, wie durch den Einsatz von Wikis das Anforderungsmanagement von Software Projekten agil unterstützt werden kann. Um das oftmals chaotische Wachstum von Inhalten in den Griff zu bekommen, werden maschinelle Lernverfahren genutzt, um Inhalte zu strukturieren und dem Benutzer zugänglich zum machen.

  16. Finite element analysis for interfacial stress and fatigue behaviors of biomimetic titanium implant under static and dynamic loading conditions.

    Science.gov (United States)

    Chen, Liangjian; Guo, Xiaoping; Li, Yimin; Li, Ting

    2010-07-01

    To investigate the stress distributions on implant-bone interface and fatigue behaviors of biomimetic titanium implant under static and dynamic loading conditions to provide theoretical basis for a new implant which may effectively transfer the stress to surrounding bones. A 3-D finite element model of a posterior mandible segment with an implant bone was constructed by a CAD (Pro/E Widefire 2.0) software. Two different implant models (a dense implant No.1 and a biomimetic implant No.2) were designed. The stress distributions on bone-implant interface under dynamic and static loading conditions were analyzed by Ansys Workbench 10.0 software, as well as the fatigue behavior of the biomimetic implant. The cervical cortical bones in the 2 implants were all high stress region under the same loading condition. The maximum von Mises stress on the interface and high-stress region in the cancellous bone region, and the maximum stress in the root region of the biomimetic implant were lower than those of the dense implant. The stress on the implant-bone interface decreased from the top to the bottom. The stress in the cervical cortical bone under the dynamic loading was 17.15% higher than that of the static loading. There was no significant difference in maximum stress at the cortical bone region between the dynamic and static loading conditions. The maximum stress of the dense implant in the cancellous bone region was 75.97% higher and that in the root region was 22.46% higher than that of the biomimetic implant. The maximum stress on the implant-bone interface was far less than the yield strength of pure titanium. The stress distribution in the cortical region of the biomimetic implant was 7.85% higher than that of the dense implant, and the maximum stress in the cortical bone was smaller than the yield stress of cortical bone. Within the dynamic loading of 50-300 N, the safety coefficient was all higher than 10, and with the increase of loading pressure, interface stress

  17. Multivariat-statistische Auswertung von energiedispersiven Röntgenfluoreszenzspektren zur Identifizierung von Substanzen

    OpenAIRE

    Kessler, Thorsten

    2001-01-01

    Es wurde der Einsatz von multivariater Auswertung von energiedispersiven Röntgenfluoreszenzanalyse (EDRFA) -Spektren für die Zuordnung von Substanzen getestet. Hierbei erfolgten u. a. Untersuchungen zur Zuordnungsanalytik von Chemikalien ohne und mit Verpackungen. Zur Untersuchung von Chemikalien mit Verpackung wurden ausschließlich anorganische, feste Chemikalien in z.T. unterschiedlicher Verpackung herangezogen. Zusätzlich sollte ein Vergleich zwischen Messungen durch gleiche Verpackungen u...

  18. Homopteren von Java, gesammelt von Herrn Edw. Jacobson

    NARCIS (Netherlands)

    Melichar, L.

    1914-01-01

    Herr Edw. Jacobson hat auf Java in den Jahren 1908— 1910 Homopteren gesammelt und mir die Bearbeitung des gesammelten Materiales übertragen. Die Jacobson’sche Ausbeute ist insoferne bemerkenswert, als dieselbe viele Mikrohomopteren enthält, welche von nichtfachkundigen Sammlern gewöhnlich nicht

  19. Regular and platform switching: bone stress analysis varying implant type.

    Science.gov (United States)

    Gurgel-Juarez, Nália Cecília; de Almeida, Erika Oliveira; Rocha, Eduardo Passos; Freitas, Amílcar Chagas; Anchieta, Rodolfo Bruniera; de Vargas, Luis Carlos Merçon; Kina, Sidney; França, Fabiana Mantovani Gomes

    2012-04-01

    This study aimed to evaluate stress distribution on peri-implant bone simulating the influence of platform switching in external and internal hexagon implants using three-dimensional finite element analysis. Four mathematical models of a central incisor supported by an implant were created: External Regular model (ER) with 5.0 mm × 11.5 mm external hexagon implant and 5.0 mm abutment (0% abutment shifting), Internal Regular model (IR) with 4.5 mm × 11.5 mm internal hexagon implant and 4.5 mm abutment (0% abutment shifting), External Switching model (ES) with 5.0 mm × 11.5 mm external hexagon implant and 4.1 mm abutment (18% abutment shifting), and Internal Switching model (IS) with 4.5 mm × 11.5 mm internal hexagon implant and 3.8 mm abutment (15% abutment shifting). The models were created by SolidWorks software. The numerical analysis was performed using ANSYS Workbench. Oblique forces (100 N) were applied to the palatal surface of the central incisor. The maximum (σ(max)) and minimum (σ(min)) principal stress, equivalent von Mises stress (σ(vM)), and maximum principal elastic strain (ε(max)) values were evaluated for the cortical and trabecular bone. For cortical bone, the highest stress values (σ(max) and σ(vm) ) (MPa) were observed in IR (87.4 and 82.3), followed by IS (83.3 and 72.4), ER (82 and 65.1), and ES (56.7 and 51.6). For ε(max), IR showed the highest stress (5.46e-003), followed by IS (5.23e-003), ER (5.22e-003), and ES (3.67e-003). For the trabecular bone, the highest stress values (σ(max)) (MPa) were observed in ER (12.5), followed by IS (12), ES (11.9), and IR (4.95). For σ(vM), the highest stress values (MPa) were observed in IS (9.65), followed by ER (9.3), ES (8.61), and IR (5.62). For ε(max) , ER showed the highest stress (5.5e-003), followed by ES (5.43e-003), IS (3.75e-003), and IR (3.15e-003). The influence of platform switching was more evident for cortical bone than for trabecular bone, mainly for the external hexagon

  20. 2D FEA of evaluation of micromovements and stresses at bone-implant interface in immediately loaded tapered implants in the posterior maxilla

    Directory of Open Access Journals (Sweden)

    Shrikar R Desai

    2013-01-01

    Full Text Available Aim: The aim of the study is to evaluate the influence implant length on stress distribution at bone implant interface in single immediately loaded implants when placed in D4 bone quality. Materials and Methods: A 2-dimensional finite element models were developed to simulate two types of implant designs, standard 3.75 mm-diameter tapered body implants of 6 and 10 mm lengths. The implants were placed in D4 bone quality with a cortical bone thickness of 0.5 mm. The implant design incorporated microthreads at the crestal part and the rest of the implant body incorporated Acme threads. The Acme thread form has a 29° thread angle with a thread height half of the pitch; the apex and valley are flat. A 100 N of force was applied vertically and in the oblique direction (at an angle of 45° to the long axis of the implants. The respective material properties were assigned. Micro-movements and stresses at the bone implant interface were evaluated. Results: The results of total deformation (micro-movement and Von mises stress were found to be lower for tapered long implant (10 mm than short implant (6 mm while using both vertical as well as oblique loading. Conclusion: Short implants can be successfully placed in poor bone quality under immediate loading protocol. The novel approach of the combination of microthreads at the crestal portion and acme threads for body portion of implant fixture gave promising results.

  1. Replikation von µ-Peptidarrays

    OpenAIRE

    Striffler, Jakob

    2014-01-01

    In der vorliegen Arbeit wurde ein Verfahren erarbeitet und mit Photometrie, XPS und ToF-SIMS charakterisiert, mit dem durch mikropartikelbasierte Verfahren hergestellte µ-Peptidarrays von Syntheseoberflächen abgespalten und auf beliebige Zieloberflächen transferiert werden können.

  2. Von Krahl ON! / Terje Metsavas

    Index Scriptorium Estoniae

    Metsavas, Terje

    2008-01-01

    Madli Pesti ja Terje Metsavas kohtusid Von Krahli teatri tehnilise meeskonnaga teatri black-box-saalis. Teatri tehniline meeskond on tehnikadirektor Enar Tarmo, video- ja multimeediaga tegelev Lauri Sepp, tehnikud Janno "John" Jaanus, Oliver Kulpsoo ja Allan Räim. Selles, kuidas sünnivad "tehnikaimed" ja kuidas lahendatakse lavastuslikke projekte

  3. Integration von Produktion und Instandhaltung

    OpenAIRE

    Hans-Böckler-Stiftung

    2003-01-01

    Die Faktoren Produktqualität und Kosten-Nutzen-Verhältnis sind entscheidend im Wettbewerb. Um diese Faktoren zu optimieren, suchen die Unternehmen nach innovativen Modellen der Integration von Produktion und Instandhaltung. Über Konzeption und Erprobung solcher Modelle berichtet eine Arbeitsgruppe der Engeren Mitarbeiter der Arbeitsdirektoren Stahl Fachausschuss 1/00.

  4. Effects of threaded post placement on strain and stress distribution of endodontically treated teeth

    Directory of Open Access Journals (Sweden)

    Paulo Cesar Freitas Santos Filho

    2013-07-01

    Full Text Available The aim of this study was to evaluate the effect of parallel and tapered threaded post placement on the strain and stress distribution of endodontically treated teeth. Fifteen bovine incisors were sectioned 15 mm from their apices, endodontically treated, and divided into three groups (n = 5 according to three different threaded posts: parallel threaded post (Radix-Anker, RA; tapered threaded post (Euro-Post, EP and tapered threaded post (Reforpost II, RII. A strain-gauge was fixed on the proximal surface perpendicular to the long root axis, 2 mm from the cervical limit. Strain generated during post placement was recorded and compared using one-way ANOVA and Tukey's test (α= .05. A scanning electron microscope was used to examine the longitudinal root sections. Stress was evaluated for each group in a two-dimensional finite element analysis. The models were meshed with tetrahedron elements and loaded with 2 N at an angle of 135° to the lingual face. The equivalent Von Mises stress was calculated. The one-way ANOVA showed significant difference among the groups. The RA group (150.0 ± 12.2 A produced higher external strain than the RII (80.0 ± 12.2 B and the EP (70.0 ± 6.1 B groups. The inner strain was approximately five times greater than the external dentin strain. High stress concentrations in each thread of the posts were observed. Scanning electron micrographs showed cracks that started in the threads of the posts. The threaded post placement induced root strain mainly on the parallel side post. Root strain and stress concentration on the post threads tended to create cracks in the inner root canal dentin.

  5. The effect of bearing congruency, thickness and alignment on the stresses in unicompartmental knee replacements.

    Science.gov (United States)

    Simpson, D J; Gray, H; D'Lima, D; Murray, D W; Gill, H S

    2008-11-01

    Unicompartmental knee replacement offers an effective treatment for patients with single compartment knee disease and is becoming an increasingly popular alternative to total knee replacement. An important cause of failure in a unicompartmental knee replacement implant is polyethylene wear. Significant contributory factors to the amount of polyethylene wear are contact stress, bearing alignment, congruency and thickness. Four different unicompartmental knee replacement implant designs (Fully-Congruent; Partially-Congruent; Non-Congruent-metal-backed; Non-Congruent-all-polyethylene) were inserted into a validated finite element model of a proximal tibia. The effect that bearing congruency, alignment and thickness had on the polyethylene stresses during a simulated step-up activity for each design was investigated. Additionally, contact pressures were compared to those calculated from Hertz elastic theory. Only the Fully-Congruent bearing experienced peak von Mises and contact stresses below the lower fatigue limit for polyethylene during the step-up activity. The highest polyethylene contact stresses were observed for the Partially-Congruent and Non-Congruent-metal-backed designs, which experienced approximately three times the polyethylene lower fatigue limit. Increasing the bearing thickness from 3.5mm to 8.5mm of the Non-Congruent design decreased the contact stresses in the bearing; however they did not fall below the lower fatigue limit for polyethylene. Good agreement between finite element and Hertz contact pressures was found. Fully congruent unicompartmental knee replacement bearings can be markedly thinner without approaching the material failure limit, have a greater potential to preserve bone stock and are less likely to fail mechanically.

  6. [Friedrich Ludwig von Maydelli pildid Baltimaade ajaloost = Friedrich Ludwig von Maydells Baltische Geschichte in Bildern = Friedrich Ludwig von Maydell ́s Baltic history in images] / Ulrike Plath

    Index Scriptorium Estoniae

    Plath, Ulrike, 1972-

    2014-01-01

    Arvustus: Friedrich Ludwig von Maydelli pildid Baltimaade ajaloost = Friedrich Ludwig von Maydells Baltische Geschichte in Bildern = Friedrich Ludwig von Maydell ́s Baltic history in images. Eesti kunstimuuseum, Kadrioru kunstimuuseum. Tallinn 2013

  7. Evaluation de la connaissance et de la mise en oeuvre des bonnes ...

    African Journals Online (AJOL)

    L'objectif de l'étude a été d'apprécier la connaissance et la mise en oeuvre des bonnes pratiques d'hygiène et des bonnes pratiques de gestion environnementale par les populations du lac Nokoué. Pour atteindre cet ... 280 people were interviewed and data collected, analyzed thanks to SPSS 16 software and Excel table.

  8. Gestionnaire, Communications électroniques (h/f) (mise à jour le 27 ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    27 janv. 2017 ... Le titulaire est aussi responsable d'évaluer l'efficacité des initiatives de marketing numériques du CRDI et de produire des rapports en temps ... Élaborer des stratégies de médias numériques (y compris les médias sociaux) qui appuient le Plan de mise en oeuvre des communications et d'autres stratégies.

  9. The Definition of Inflation According to Mises: Implications for the Debate on Free Banking

    Directory of Open Access Journals (Sweden)

    Nicolás Cachanosky

    Full Text Available The discussion of what is and what is not inflation has become central among the Austrian economists in their debate between free banking with fractional reserves versus banking with 100-percent reserve. Many Austrians also turn to the writings of Mises to find out what the dean of Austrian Economics thought about inflation, but there is no agreement on the interpretation of his writings either. This article tries to contribute to the interpretation of Mises’ concept of inflation.

  10. Mise en évidence d'une variation intra spécifique chez Botrytis ...

    African Journals Online (AJOL)

    Objectifs : Le présent travail oeuvre pour la mise en évidence de la variation intra spécifique chez Botrytis cinerea et de l'effet d'un extrait d'un compost de déchets urbains solides sur deux stades du cycle de vie de ce pathogène. Methodologie et Résultats : Des feuilles de tomate ont été inoculées par 22 souches de B.

  11. IITA_IATI Plan mise en oeuvre CRDI 10-08-15.xlsx

    International Development Research Centre (IDRC) Digital Library (Canada)

    bporrett

    1 juil. 2016 ... Appliquer un standard commun et ouvert pour la publication par voie électronique en temps voulu d'informations détaillées et prévisionnelles sur les ressources ... les conditions dont elle dépend (comme la mise en place d'un nouveau système de gestion),. - les conditions requises pour que les données ...

  12. Participation des hommes aux soins aux enfants avant la mise en ...

    African Journals Online (AJOL)

    Participation des hommes aux soins aux enfants avant la mise en oeuvre de la composante familiale et communautaire de la stratégie «prise en charge intégrée des ... In the case of accident occurred in children, the decision of the therapeutic route came from the father in 71.4% of the cases, and the rugged child care ...

  13. The Protocolised Management in Sepsis (ProMISe) trial statistical analysis plan.

    Science.gov (United States)

    Power, G Sarah; Harrison, David A; Mouncey, Paul R; Osborn, Tiffany M; Harvey, Sheila E; Rowan, Kathryn M

    2013-12-01

    The Protocolised Management in Sepsis (ProMISe) trial is an open, multicentre, randomised controlled trial (RCT) of the clinical effectiveness and cost-effectiveness of early, goal directed, protocolised resuscitation compared with usual resuscitation for patients presenting to emergency departments (EDs) in the United Kingdom with early signs of severe sepsis or septic shock. The rationale for the ProMISe trial derives from a single-centre United States RCT that reported a reduction in hospital mortality from 46.5% to 30.5%. To describe the proposed statistical analyses for the evaluation of clinical effectiveness for the ProMISe trial. It is important to complete this plan before inspecting the data, and before completion of two related international studies, so that post-hoc, data-derived decisions are avoided. The primary and secondary outcomes were defined precisely, and the approach to safety monitoring and data collection summarised, with a description of the planned statistical analyses including prespecified subgroup and secondary analyses. The primary outcome is all-cause mortality at 90 days. The primary analysis will be reported as a relative risk and absolute risk reduction and tested with the Fisher exact test. Prespecified subgroup analyses will be based on age, baseline Medical Emergency Department Sepsis score, baseline Sequential Organ Failure Assessment score, and time from ED presentation to randomisation. Secondary analyses include adjustment for baseline covariates, estimation of learning curve effects and adjustment for noncompliance. In keeping with best practice, we have developed a statistical analysis plan for the ProMISe trial and place it in the public domain before inspecting data from the trial.

  14. Évaluation de l'incidence des mises en garde illustrées contre les ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    estimer dans quelle mesure les mises en garde illustrées apposées sur les emballages contribuent à diminuer la demande de cigarettes au Vietnam; - prédire les incidences de ces mises en garde illustrées sur la diminution de la morbidité et de la mortalité associées au tabagisme, sur l'économie et sur l'équité sociale au ...

  15. Stress

    DEFF Research Database (Denmark)

    Keller, Hanne Dauer

    2015-01-01

    Kapitlet handler om stress som følelse, og det trækker primært på de få kvalitative undersøgelser, der er lavet af stressforløb.......Kapitlet handler om stress som følelse, og det trækker primært på de få kvalitative undersøgelser, der er lavet af stressforløb....

  16. Stress distribution pattern of screw-retained restorations with segmented vs. non-segmented abutments: A finite element analysis.

    Science.gov (United States)

    Aalaei, Shima; Rajabi Naraki, Zahra; Nematollahi, Fatemeh; Beyabanaki, Elaheh; Shahrokhi Rad, Afsaneh

    2017-01-01

    Background. Screw-retained restorations are favored in some clinical situations such as limited inter-occlusal spaces. This study was designed to compare stresses developed in the peri-implant bone in two different types of screw-retained restorations (segmented vs. non-segmented abutment) using a finite element model. Methods. An implant, 4.1 mm in diameter and 10 mm in length, was placed in the first molar site of a mandibular model with 1 mm of cortical bone on the buccal and lingual sides. Segmented and non-segmented screw abutments with their crowns were placed on the simulated implant in each model. After loading (100 N, axial and 45° non-axial), von Mises stress was recorded using ANSYS software, version 12.0.1. Results. The maximum stresses in the non-segmented abutment screw were less than those of segmented abutment (87 vs. 100, and 375 vs. 430 MPa under axial and non-axial loading, respectively). The maximum stresses in the peri-implant bone for the model with segmented abutment were less than those of non-segmented ones (21 vs. 24 MPa, and 31 vs. 126 MPa under vertical and angular loading, respectively). In addition, the micro-strain of peri-implant bone for the segmented abutment restoration was less than that of non-segmented abutment. Conclusion. Under axial and non-axial loadings, non-segmented abutment showed less stress concentration in the screw, while there was less stress and strain in the peri-implant bone in the segmented abutment.

  17. Deformation and stress distribution of the human foot after plantar ligaments release: a cadaveric study and finite element analysis.

    Science.gov (United States)

    Liang, Jun; Yang, Yunfeng; Yu, Guangrong; Niu, Wenxin; Wang, Yubin

    2011-03-01

    The majority of foot deformities are related to arch collapse or instability, especially the longitudinal arch. Although the relationship between the plantar fascia and arch height has been previously investigated, the stress distribution remains unclear. The aim of this study was to explore the role of the plantar ligaments in foot arch biomechanics. We constructed a geometrical detailed three-dimensional (3-D) finite element (FE) model of the human foot and ankle from computer tomography images. The model comprised the majority of joints in the foot as well as bone segments, major ligaments, and plantar soft tissue. Release of the plantar fascia and other ligaments was simulated to evaluate the corresponding biomechanical effects on load distribution of the bony and ligamentous structures. These intrinsic ligaments of the foot arch were sectioned to simulate different pathologic situations of injury to the plantar ligaments, and to explore bone segment displacement and stress distribution. The validity of the 3-D FE model was verified by comparing results with experimentally measured data via the displacement and von Mise stress of each bone segment. Plantar fascia release decreased arch height, but did not cause total collapse of the foot arch. The longitudinal foot arch was lost when all the four major plantar ligaments were sectioned simultaneously. Plantar fascia release was compromised by increased strain applied to the plantar ligaments and intensified stress in the midfoot and metatarsal bones. Load redistribution among the centralized metatarsal bones and focal stress relief at the calcaneal insertion were predicted. The 3-D FE model indicated that plantar fascia release may provide relief of focal stress and associated heel pain. However, these operative procedures may pose a risk to arch stability and clinically may produce dorsolateral midfoot pain. The initial strategy for treating plantar fasciitis should be non-operative.

  18. Von den Veranschaulichungsmethoden in den Rundfunkpredigten von der Heiligkreuz- Kirche

    Directory of Open Access Journals (Sweden)

    Witold Ostafiński

    2004-12-01

    Full Text Available In der gegenwärtigen Verkündigung des Wortes Gottes spielt die Veranschaulichung der Überlieferung eine nicht zu überschätzende Rolle. Vor diesem Hintergrund wird es sehr wichtig, dass man den Predigern nicht nur auf die Funktion des Bildes in der Verkündigung, sondern auch auf die Art und Weise seines Entstehens auf der narrativen Ebene aufmerksam macht. Während die Kenner der Homiletik die Notwendigkeit des Auftretens der Bildeigenschaften in den Predigten betonen, erinnern sie gleichzeitig daran, dass der moderne, von der „Bild-Zivilisation“ gestaltete Mensch, „immer mehr sehen als hören“ möchte. Der vorliegende, die Rundfunkpredigten von der Heiligkreuz-Kirche analysierende Aufsatz, nimmt auf und bringt zugleich nahe die Problematik der Notwendigkeit des Bildes in der Wort-Gottes-Verkündigung. Der Artikel stellt die Erzählungsform als eine wichtige Möglichkeit der Glaubensüberlieferung dar, behandelt das Problem der Aktualisierung evangelischen Werte, bringt das von den Predigten gestaltete synästhetische Weltbild nahe und analysiert die Rolle des Zitats und Beispiels (exemplum bei der Gestaltung der Bildhaftigkeit einer Predigt. Darüber hinaus überprüft der Aufsatz in seinem letzten Teil die in den gegenwärtigen Rundfunkpredigten meist verwendeten Redefiguren

  19. Analyse von Schnittstellenkompatibilität von Steuergeräten auf Basis von MSC-Beschreibungen

    OpenAIRE

    Ma, Zheng

    2008-01-01

    In modernen Fahrzeugen befindet sich eine Vielzahl von Steuergeräten, die verschiedenste Funktionen, wie z.B. das Antiblockiersystem (ABS) realisieren. Die Funktionalitäten von Steuergeräten werden heute mit unterschiedlichen Methoden beschrieben. Eine dieser Methoden sind Message Sequence Charts (MSCs). Aufgrund der Freiheitsgrade von MSCs gibt es verschiedene Möglichkeiten gleiche Funktionalität unterschiedlich zu beschreiben. In dieser Arbeit wird eine Methode definiert, wie...

  20. Männlichkeiten von rechts

    Directory of Open Access Journals (Sweden)

    Marc Gärtner

    2004-11-01

    Full Text Available Oliver Geden, Doktorand am Institut für europäische Ethnologie der Humboldt Universität Berlin untersucht Männlichkeitskonzepte im zeitgenössischen Rechtspopulismus – ein Thema, zu dem überraschend lange keine einschlägigen Studien vorlagen. Anhand von Parteimedien und Interviews rekonstruiert er strategische Positionen zu Männlichkeit und Geschlechterverhältnissen auf unterschiedlichen Organisationsebenen der Österreichischen „Haider-Partei“ FPÖ. Statt eines monolithischen „Neo-Macho-Projektes“ findet er im Kern zwar ähnliche Traditionalisierungsbemühungen auf allen Ebenen, je nach Kontext aber differenzierbare pragmatische, verunsicherte und neo-naturalistische Perspektiven auf die Geschlechterthematik. Durch die Einbeziehung von Gruppeninterviews im Nachwuchsverband der Partei erhält die Publikation eine besondere Brisanz. Geden analysiert die methodischen und forschungsethischen Implikationen ebenso hervorragend wie das Kernthema selbst.

  1. Von Willebrand factor and aging.

    Science.gov (United States)

    Konkle, Barbara A

    2014-09-01

    von Willebrand factor (VWF) plays critical roles in initiating primary hemostasis and extending the half-life of coagulation factor VIII in circulation. VWF levels increase with age and elevated levels are associated with an increased risk of venous thromboembolism and cardiovascular disease (CVD). Patients with von Willebrand disease (VWD) due to a deficiency or dysfunction of VWF may have symptoms that ameliorate with aging or may have exacerbation of their disease. Bleeding sites of particular challenge in the aging patient include gastrointestinal bleeding and hematuria. Some medications used to treat VWD should be used with special precaution in older patients, including desmopressin and VWF-containing factor concentrates. Patients with VWD may have some protection from CVD, but in those patients who develop CVD, management is very challenging, given the role of antiplatelet therapy as the mainstay of treatment. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  2. Stress

    OpenAIRE

    Jensen, Line Skov; Lova, Lotte; Hansen, Zandra Kulikovsky; Schønemann, Emilie; Larsen, Line Lyngby; Colberg Olsen, Maria Sophia; Juhl, Nadja; Magnussen, Bogi Roin

    2012-01-01

    Stress er en tilstand som er meget omdiskuteret i samfundet, og dette besværliggør i en vis grad konkretiseringen af mulige løsningsforslag i bestræbelsen på at forebygge den såkaldte folkesygdom. Hovedkonklusionen er, at selv om der bliver gjort meget for at forebygge, er der ikke meget der aktivt kan sættes i værk for at reducere antallet af stressramte, før en fælles forståelse af stressårsager og effektiv stresshåndtering er fremlagt. Problemformuleringen er besvaret gennem en undersø...

  3. Description of scattering material behaviour and damage in inelastic materials; Beschreibung von streuendem Materialverhalten und von Schaedigung bei inelastischen Werkstoffen

    Energy Technology Data Exchange (ETDEWEB)

    Pensky, H.M.H.

    2000-07-01

    For realistic numerical simulations of the stress-strain behaviour of structures, models are necessary which describe elastic-inelastic and scattering material behaviour. The developed models simulate elastic, viscoplastic and anisotropic damage material phenomena. An approach is proposed for covering stochastic material beahviour by correspondingly distributed parameters of the deterministic material model. Numerical simulations of biaxial material tests and structural tests demonstrate the range of applicability. (orig.) [German] Die realitaetsnahe numerische Simulation des Spannungs-Verformungsverhaltens von Bauteilen erfordert Modelle zur Beschreibung inelastischen und streuenden Materialverhaltens. Die hier entwickelten Modelle beschreiben elastische, viskoplastische und anisotrope Schaedigungsphaenomene des Materialverhaltens. Desweiteren wird ein Konzept vorgestellt, mit dem streuendes Materialverhalten mit streuenden Materialparametersaetzen deterministischer Stoffmodelle beschreibbar ist. Numerische Simulationen von Werkstoff- und Bauteilversuchen veranschaulichen den Anwendungsbereich der Modelle. (orig.)

  4. von Hippel-Lindau disease

    DEFF Research Database (Denmark)

    Binderup, Marie Louise Mølgaard; Gimsing, Steen; Kosteljanetz, Michael

    2013-01-01

    Endolymphatic sac tumours (ELSTs) of the inner ear occur in 16% of patients with the hereditary tumor syndrome von Hippel-Lindau disease (vHL). ELSTs of all sizes can cause irreversible hearing loss which can, however, be prevented through early diagnosis and treatment. We aim to emphasize the ch...... the challenges of prophylactic ELST screening and to explore the role of audiometry in pre-symptomatic ELST screening....

  5. Methode zur Entwicklung von Prozessportalen

    OpenAIRE

    Alt, Rainer; Caesar, Marc; Leser, Florian; Österle, Hubert; Puschmann, Thomas; Reichmayr, Christian; Zurmuehlen, Rudolf

    2004-01-01

    Die in Kapitel 2 dargestellte Architektur zeigt Gestaltungselemente auf den drei Ebenen Strategie, Prozess und System. Zahlreiche Beispiele in den darauf folgenden Kapiteln haben die Anwendung dieser Architektur gezeigt. Um ein intuitives Vorgehen bei Entwurf und der Umsetzung von Echtzeit-Portalen zu vermeiden, sollen die bei den Fallbeispielen erzielten Erkenntnisse und Erfahrungen in ein systematisches Vorgehen einfliessen. Obgleich sich der Entwurf einer Architektur für das Echtzeit-Unter...

  6. Class I and Class II restorations of resin composite: an FE analysis of the influence of modulus of elasticity on stresses generated by occlusal loading.

    Science.gov (United States)

    Asmussen, Erik; Peutzfeldt, Anne

    2008-05-01

    It was the aim of the study to analyze by the FE method stresses generated in tooth and restoration by occlusal loading of Class I and Class II restorations of resin composite. On the basis of available information on the influence of the modulus of elasticity, the research hypothesis was that the marginal stresses would decrease with increasing modulus of elasticity of the restoration. A cylindrical tooth was modelled in enamel and dentin and fitted with a Class I or a Class II restoration of resin composite. In one scenario the restoration was bonded to the tooth, in another the restoration was left nonbonded. The resin composite was modelled with a modulus of elasticity of 5, 10, 15 or 20 GPa and loaded occlusally with 100 N. By means of the soft-ware program ABAQUS the von Mises stresses in enamel and dentin were calculated. In the bonded scenario, the maximum stresses in the enamel were located at the occlusal margins (range 7-11 MPa), and in the dentin centrally at the pulpal floor (range 3.4-5.5MPa). The stresses decreased with increasing modulus of elasticity of the resin composite. In the nonbonded scenario, the stresses were higher in the dentin and lower in the enamel than in the bonded cases, and the influence of the modulus of elasticity was less pronounced. The marginal stresses in the restoration were below 6 MPa in the bonded scenario and below 3 MPa in the nonbonded scenario. Occlusal restorations of resin composite should have a high modulus of elasticity in order to reduce the risk of marginal deterioration.

  7. Stress distribution and micromotion analyses of immediately loaded implants of varying lengths in the mandible and fibular bone grafts: a three-dimensional finite element analysis.

    Science.gov (United States)

    Wu, Jacqueline Chia-Hsuan; Chen, Chen-Sheng; Yip, Shing-Wai; Hsu, Ming-Lun

    2012-01-01

    The aim of the present study was to compare the biomechanical effects of different lengths of implants in an immediate loading condition in mandibular and fibular bone. Three-dimensional (3D) nonlinear finite element analysis (FEA) was used to examine the complex irregular structures. The variables of this research were the two different bone types (mandible and fibula) and three different implant lengths. Simplified half models were constructed for 3D FEA. Three different implant lengths (6 mm, 10 mm, and 15 mm) were inserted into the mandibular and fibular bone models, which were made to simulate immediate implant loading conditions. A load of 125 N was applied to the center of the suprastructure at a 45-degree angle relative to the long axis of the implant, and the resultant maximum von Mises equivalent (EQV) stresses, stress distribution, strain energy, and micromotion were measured. In the mandible, the maximum EQV stresses were 115.636 MPa, 155.943 MPa, and 157.105 MPa with the 6-mm, 10-mm, and 15-mm implants, respectively. The mean EQV stresses were 64.145 MPa, 77.925 MPa, and 78.500 MPa, respectively. In the fibula, the maximum EQV stresses were 174.04 MPa, 157.456 MPa, and 144.353 MPa with the 6-mm, 10-mm, and 15-mm implants, respectively. The mean EQV stresses were 82.329 MPa, 73.526 MPa, and 74.050 MPa, respectively. The micromotion in the fibula models was lower than that seen in the mandible models. EQV stress in the fibular bone was different from that in the mandible. Short implants can be an option for oral rehabilitation in the mandible; however, implants in the fibula should probably have bicortical engagement.

  8. Effect of framework material and vertical misfit on stress distribution in implant-supported partial prosthesis under load application: 3-D finite element analysis.

    Science.gov (United States)

    Bacchi, Ataís; Consani, Rafael Leonardo Xediek; Mesquita, Marcelo Ferraz; Dos Santos, Mateus Bertolini Fernandes

    2013-09-01

    This study evaluated the influence of framework material and vertical misfit on stress created in an implant-supported partial prosthesis under load application. The posterior part of a severely reabsorbed jaw with a fixed partial prosthesis above two osseointegrated titanium implants at the place of the second premolar and second molar was modeled using SolidWorks 2010 software. Finite element models were obtained by importing the solid model into an ANSYS Workbench 11 simulation. The models were divided into 15 groups according to their prosthetic framework material (type IV gold alloy, silver-palladium alloy, commercially pure titanium, cobalt-chromium alloy or zirconia) and vertical misfit level (10 µm, 50 µm and 100 µm). After settlement of the prosthesis with the closure of the misfit, simultaneous loads of 110 N vertical and 15 N horizontal were applied on the occlusal and lingual faces of each tooth, respectively. The data was evaluated using Maximum Principal Stress (framework, porcelain veneer and bone tissue) and a von Mises Stress (retention screw) provided by the software. As a result, stiffer frameworks presented higher stress concentrations; however, these frameworks led to lower stresses in the porcelain veneer, the retention screw (faced to 10 µm and 50 µm of the misfit) and the peri-implant bone tissues. The increase in the vertical misfit resulted in stress values increasing in all of the prosthetic structures and peri-implant bone tissues. The framework material and vertical misfit level presented a relevant influence on the stresses for all of the structures evaluated.

  9. Cortical bone stress distribution in mandibles with different configurations restored with prefabricated bar-prosthesis protocol: a three-dimensional finite-element analysis.

    Science.gov (United States)

    de Almeida, Erika Oliveira; Rocha, Eduardo Passos; Assunção, Wirley Gonçalves; Júnior, Amílcar Chagas Freitas; Anchieta, Rodolfo Bruniera

    2011-01-01

    To evaluate stress distribution in different horizontal mandibular arch formats restored by protocol-type prostheses using three-dimensional finite element analysis (3D-FEA). A representative model (M) of a completely edentulous mandible restored with a prefabricated bar using four interforaminal implants was created using SolidWorks 2010 software (Inovart, São Paulo, Brazil) and analyzed by Ansys Workbench 10.0 (Swanson Analysis Inc., Houston, PA) to obtain the stress fields. Three mandibular arch sizes were considered for analysis, regular (M), small (MS), and large (ML). Three unilateral posterior loads (L) (150 N) were used: perpendicular to the prefabricated bar (L1); 30° oblique in a buccolingual direction (L2); 30° oblique in a lingual-buccal direction (L3). The maximum and minimum principal stresses (σ(max), σ(min)), the equivalent von Mises (σ(vM)), and the maximum principal strain (σ(max) ) were obtained for type I (M.I) and type II (M.II) cortical bones. Tensile stress was more evident than compression stress in type I and II bone; however, type II bone showed lower stress values. The L2 condition showed highest values for all parameters (σ(vM), σ(max), σ(min), ɛ(max)). The σ(vM) was highest for the large and small mandibular arches. The large arch model had a higher influence on σ(max) values than did the other formats, mainly for type I bone. Vertical and buccolingual loads showed considerable influence on both σ(max) and σ(min) stresses. © 2010 by The American College of Prosthodontists.

  10. Computer and experimental analyses of the stress state in the cement hip joint endoprosthesis body.

    Science.gov (United States)

    Tabaković, Slobodan; Grujić, Jovan; Zeljković, Milan; Blagojević, Zoran; Radojević, Bojan; Popović, Zoran; Zivković, Aleksandar; Stevanović, Vladan

    2014-11-01

    One of the possible complications after implantation of a cement hip-joint endoprosthesis is frac- ture in the endoprosthesis body. Fractures arise from overload or material fatigue of which an implant is made. The purpose of this research was to define the intensity of maximum stress and the positions of a critical cross-section in the endoprosthesis body. Unilaterally changing forces which act on the hip joint during walking as well as the loads result in flexible deformations of the endoprosthesis body. Biomechanical analysis of the forces acting on the hip joint determine their direction and intensity, whereas on the basis of Gruen's classification of the endoprosthesis body loosening the level of fixation is established. The bodies of cement hip joint endoprosthesis are made of cobalt-chromium-molybdenum (CoCrMo) alloy, suitable for vacuum casting, are submitted to the analysis. Analysis of the critical stress in the endoprosthesis body was performed on the endoprosthesis body by means of the finite element method. The experimental verification of the obtained results was carried out on the physical prototype under laboratory conditions. Computer analysis, by means of the finite element method, determined the stress state by calculation of the maximum Von Mises stress and critical cross-sections for different angles of the resultant force action. The results obtained by the computer and experimental method correlate and are comparable to the results of similar analyses conducted on various endoprosthesis types. The analyses described in the paper make the basis for improving the process designing of hip joint endoprostheses and their customization to each individual patient (custom made).

  11. Influence of diameter and intraradicular post in the stress distribution. Finite element analysis

    Directory of Open Access Journals (Sweden)

    Cleidiel Aparecido Araujo LEMOS

    Full Text Available Abstract Introduction The biomechanical behavior of endodontically treated teeth depending on the selected restorative material and tooth situation to be restored. Objective To analyze by the two-dimensional finite element method the biomechanical behavior of different diameters in intraradicular posts and teeth with coronal remaining of 2mm. Material and method Six models were made with three types of posts, as follows: Glass fiber post, carbon fiber post, and cast metal post, both with diameter # 1 (1.1 mm in diameter and # 2 (1.3 mm of diameter. The modeling was performed using the Rhinoceros 4.0 program. The FEMAP 10.2 and NEiNastran 9.2 programs were used to develop finite element models. The loading used was 100N for axial and oblique forces. The results were visualized using the von Mises stress map. The statistical analysis was made using analysis of variance (ANOVA and Tukey post-test, with a significance level of 5%. Result The oblique loading stress values were higher than the axial loading (p<0.001 for both situations. The glass fiber post showed the lowest concentrations of stress on both loads (p<0.001. The carbon fiber post presented significant difference compared to the cast metal post, only in the oblique load (p=0.007. The diameter did not increase the stress of the evaluated posts (p=0.302. Conclusion The fiber posts were more favorable for restoration of endodontically treated teeth; the increase of diameter did not influence the increase of tension; the oblique load was more harmful for both posts and tooth structure.

  12. Influence of local meshing size on stress intensity factor of orthopedic lag screw

    Science.gov (United States)

    Husain, M. N.; Daud, R.; Basaruddin, K. S.; Mat, F.; Bajuri, M. Y.; Arifin, A. K.

    2017-09-01

    Linear elastic fracture mechanics (LEFM) concept is generally used to study the influence of crack on the performance of structures. In order to study the LEFM concept on damaged structure, the usage of finite element analysis software is implemented to do the simulation of the structure. Mesh generation is one of the most crucial procedures in finite element method. For the structure that crack or damaged, it is very important to determine the accurate local meshing size at the crack tip of the crack itself in order to get the accurate value of stress intensity factor, KI. Pre crack will be introduced to the lag screw based on the von mises' stress result that had been performed in previous research. This paper shows the influence of local mesh arrangement on numerical value of the stress intensity factor, KI obtained by the displacement method. This study aims to simulate the effect of local meshing which is the singularity region on stress intensity factor, KI to the critical point of failure in screw. Five different set of wedges meshing size are introduced during the simulation of finite element analysis. The number of wedges used to simulate this research is 8, 10, 14, 16 and 20. There are three set of numerical equations used to validate the results which are brown and srawley, gross and brown and Tada equation. The result obtained from the finite element software (ANSYS APDL) has a positive agreement with the numerical analysis which is Brown and Srawley compared to other numerical formula. Radius of first row size of 0.014 and singularity element with 14 numbers of wedges is proved to be the best local meshing for this study.

  13. [Influence of attachment type on stress distribution of implant-supported removable partial dentures].

    Science.gov (United States)

    Yang, Xue; Rong, Qi-guo; Yang, Ya-dong

    2015-02-18

    To compare influences of different retention attachments on stress among supporting structures. By 3-dimensional laser scanner and reverse engineering computer aided design (CAD) software, a basic partially edentulous digital model with mandibular premolar and molar missing was established. Implant attachment and removable partial dentures (RPD) were added into the basic model to build three kinds of models: RPD only, RPD + implant + Locator attachment, and RPD + implant + Magfit attachment. Vertical and inclined loads were put on artificial teeth unilaterally. By means of 3-dimensional finite element analysis, the stress distribution and displacement of the main supportive structures were compared. A complete 3-dimensional finite element model was established, which contained tooth structure, and periodontal structures. The displacement of the denture was smaller in Locator (9.38 μm vertically, 45.48 μm obliquely) and Magfit models (9.54 μm vertically, 39.45 μm obliquely) compared with non-implant RPD model (95.27 μm vertically, 155.70 μm obliquely). Compared with the two different attachments, cortical bone stress value was higher in Locator model (Locator model 10.850 MPa vertically, 43.760 MPa obliquely; Magfit model 7.100 MPa vertically, 19.260 MPa obliquely).The stress value of abutment periodontal ligamentin Magfit model (0.420 MPa vertically) was lower than that in Locator model (0.520 MPa vertically). The existence of implant could reduce maximum von Mises value of each supportive structure when Kennedy I partially edentulous mandible was restored. Comparing the structure of Magfit and Locator attachment, the contact of Magfit attachment was rigid, while Locator was resilient. Locator attachment could improve stability of the denture dramatically. Locator had stronger effect on defending horizontal movement of the denture.

  14. Einfluss von Hypoxie auf das Transkriptom und das mitochondriale Proteom von Arabidopsis thaliana

    OpenAIRE

    Willeke, Claudia

    2011-01-01

    Hypoxie beeinflusst Wachstum und Entwicklung von Pflanzen. Da Sauerstoff als finaler Elektronenakzeptor der Atmungskette dient, sind Mitochondrien möglicherweise an der Wahrnehmung von Hypoxie und der Weiterleitung des Signals durch retrograde Regulierung beteiligt. In dieser Arbeit wurden daher die Auswirkungen von Hypoxie auf das Transkriptom und das mitochondriale Proteom von Arabidopsis thaliana untersucht. Zu diesem Zweck wurden Inkubationssysteme für Zellkulturen, Keimlinge und Pflanzen...

  15. Dr. von Braun Briefing Walt Disney

    Science.gov (United States)

    1965-01-01

    Dr. von Braun began his association with Walt Disney in the 1950s when the rocket scientist appeared in three Disney television productions related to the exploration of space. Years later, Dr. von Braun invited Disney and his associates to tour the Marshall Space Flight Center (MSFC) in Huntsville, Alabama. This photograph is dated April 13, 1965. From left are R.J. Schwinghamer from the MSFC, Disney, B.J. Bernight, and Dr. von Braun.

  16. Offenes Baukastensystem zur effizienten Dimensionierung von Materialflusssystemen

    OpenAIRE

    Meinhardt, Ingolf; Marquardt, Hans-Georg

    2007-01-01

    Die optimale Gestaltung logistischer Systeme und Prozesse bekommt eine immer größere Bedeutung für die Wirtschaftlichkeit und Wettbewerbsfähigkeit von Unternehmen. Für Einzelkomponenten von Materi-alflusssystemen sind neben exakten analytischen Verfahren auch Näherungslösungen und Ersatzmodelle in Form von Polynomen, neuronalen Netzen oder zeitdiskreten Verfahren vorhanden, mit denen eine gute Nachbildung des Verhaltens dieser Komponenten möglich ist. Ziel des Baukastensystems ist es, für...

  17. von Willebrand disease phenotype and von Willebrand factor marker genotype in Doberman Pinschers.

    Science.gov (United States)

    Brooks, M B; Erb, H N; Foureman, P A; Ray, K

    2001-03-01

    To define the relationship between clinical expression of a type-1 von Willebrand disease phenotype and genotype at 2 von Willebrand factor marker loci in Doberman Pinschers. 102 client-owned Doberman Pinschers. Dogs were recruited on the basis of plasma von Willebrand factor concentration, clinical history, and pedigree. Blood samples and response to a history questionnaire were obtained for each dog. Plasma von Willebrand factor concentration was measured by use of an ELISA, and genotyping was performed via polymerase chain reaction for 1 intragenic and 1 extragenic von Willebrand factor marker. Amplification product size was determined by use of polyacrylamide gel electrophoresis (intragenic marker) or automated sequence analysis (extragenic marker). Western blots were prepared from a subset of dogs with low plasma von Willebrand factor concentration to evaluate multimer distribution. Strong associations were detected between plasma von Willebrand factor concentration and von Willebrand factor marker genotype. Twenty-five dogs had substantial reduction in plasma von Willebrand factor concentration and multiple hemorrhagic events. All were homozygous for a 157-base-pair intragenic marker allele and homozygous or compound heterozygous for 1 of 4 extragenic marker alleles. These marker genotypes were exclusively detected in dogs with low plasma von Willebrand factor concentration, although some dogs with these genotypes did not have abnormal bleeding. Type-1 von Willebrand disease in Doberman Pinschers is associated with the von Willebrand factor gene locus; however, the expression pattern in this breed appears more complex than that of a simple recessive trait.

  18. Modellierung von Anwenderverhalten im Social Semantic Web

    Science.gov (United States)

    Ulbrich, Armin; Höfler, Patrick; Lindstaedt, Stefanie

    Ziel dieses Kapitels ist es, gemeinsame Verwendungsszenarien des Semantic Web und des Social Web zu identifizieren und zu benennen. Dabei wird ein Teilaspekt des Themengebiets im Detail betrachtet: die Nutzung von Services, die Beobachtungen des Verhaltens von Anwendern analysieren, um daraus maschinell interpretierbare Informationen zu erhalten und diese als Modelle zu organisieren. Es werden zunächst einige Eigenschaften und Unterscheidungsmerkmale von Anwenderverhalten und organisierten Modellen dargestellt. Anschließend wird der mögliche wechselseitige Nutzen von Anwenderverhalten und Modellen diskutiert. Den Abschluss bildet eine Betrachtung einiger exemplarischer Software-Services, die heute schon verwendet werden, um Anwenderverhalten in Modelle überzuführen.

  19. The Social Science of Carl von Clausewitz

    Science.gov (United States)

    2006-01-01

    The Social Science of Carl von Clausewitz JANEEN KLINGER C arl von Clausewitz’s great, unfinished book On War is well-known as be- ing prone to...COVERED 00-00-2006 to 00-00-2006 4. TITLE AND SUBTITLE The Social Science of Carl von Clausewitz 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c...Raymond Aron, Clausewitz: Philos- opher of War (New York: Simon and Schuster, 1983), p. 206. 88 Parameters 2. Carl Von Clausewitz , On War, ed. and trans

  20. Die naturräumliche Gliederung von Schwaben

    OpenAIRE

    Fischer, Klaus

    1985-01-01

    Die naturräumliche Gliederung von Schwaben. - In: Historischer Atlas von Bayerisch-Schwaben / hrsg. von Hans Frei ... - 2., neu bearb. u. erg. Aufl. - Augsburg : Schwäb. Forschungsgem. - Lifg. 2. (1985). - Kt. II, 7.

  1. Periodontal ligament influence on the stress distribution in a removable partial denture supported by implant: a finite element analysis

    Directory of Open Access Journals (Sweden)

    Carlos Marcelo Archangelo

    2012-06-01

    Full Text Available OBJECTIVES: The non-homogenous aspect of periodontal ligament (PDL has been examined using finite element analysis (FEA to better simulate PDL behavior. The aim of this study was to assess, by 2-D FEA, the influence of non-homogenous PDL on the stress distribution when the free-end saddle removable partial denture (RPD is partially supported by an osseointegrated implant. MATERIAL AND METHODS: Six finite element (FE models of a partially edentulous mandible were created to represent two types of PDL (non-homogenous and homogenous and two types of RPD (conventional RPD, supported by tooth and fibromucosa; and modified RPD, supported by tooth and implant [10.00x3.75 mm]. Two additional Fe models without RPD were used as control models. The non-homogenous PDL was modeled using beam elements to simulate the crest, horizontal, oblique and apical fibers. The load (50 N was applied in each cusp simultaneously. Regarding boundary conditions the border of alveolar ridge was fixed along the x axis. The FE software (Ansys 10.0 was used to compute the stress fields, and the von Mises stress criterion (svM was applied to analyze the results. RESULTS: The peak of svM in non-homogenous PDL was higher than that for the homogenous condition. The benefits of implants were enhanced for the non-homogenous PDL condition, with drastic svM reduction on the posterior half of the alveolar ridge. The implant did not reduce the stress on the support tooth for both PDL conditions. Conclusion: The PDL modeled in the non-homogeneous form increased the benefits of the osseointegrated implant in comparison with the homogeneous condition. Using the non-homogenous PDL, the presence of osseointegrated implant did not reduce the stress on the supporting tooth.

  2. Finite element stress analysis of diastema closure with ceramic laminate veneers.

    Science.gov (United States)

    Chander, N Gopi; Padmanabhan, T V

    2009-10-01

    The purpose of this study was to use finite element stress analysis to examine the relative importance of variables such as porcelain laminate veneer (PLV) extensions, loading angle, and loading level for the case of feldspathic ceramic veneering of teeth to manage diastema. A 3D maxillary central incisor including its internal anatomy and morphology was constructed with ANSYS software for different extensions of PLV. Internal boundaries defining the dentinoenamel junction, the pulp-dentinal junction, the interface between the enamel-luting cement, and the porcelain-luting cement were well defined. The von Mises stresses distribution and stress intensity were analyzed on the free extension of PLV for varying extensions, various angulations (0 degrees , 30 degrees , and 60 degrees ) on the incisal edge, and for different loading levels (50, 150, and 250 N). The numerical values of stress were recorded. A significant difference in stress was observed. Increased stresses occurred with increased extensions, angulations, and loading levels. At 0 degrees angulation, compressive stresses were visualized in finite element analysis for various magnitudes of force. Higher stress values of 182 MPa and 211 MPa were obtained for the 2.5-mm extension in the mesial surface and in both proximal surfaces for 0 degrees angulation at 250 N magnitude of force. The stress occurring at 30 degrees and 60 degrees angulations was the combination of compressive and tensile stress. Higher values of 261 MPa and 232 MPa were observed when forces were applied on the mesial extension of the PLV and on both the proximal surfaces for 2.5 mm at 30 degrees , 250 N magnitude of force. A maximum stress value of 507 MPa was observed when PLV were increased in mesial width by 2.5 mm for 60 degrees angulation at 250 N magnitude of force. The extensions of PLV in diastema closure have more of an esthetic than functional consideration, but critical factors such as angulations and the loading level acting

  3. Effect of Different Treatment Options on Biomechanics of Immature Teeth: A Finite Element Stress Analysis Study.

    Science.gov (United States)

    Belli, Sema; Eraslan, Oğuz; Eskitaşcıoğlu, Gürcan

    2017-12-16

    Immature teeth (IT) can be managed by using several treatment options, depending on the vitality of the tooth. The aim of this finite element stress analysis study was to evaluate the effect of different treatment procedures on the stresses in three-dimensional IT models. Three-dimensional finite element stress analysis premolar tooth model was created as control (model 1), modified to simulate IT. Eleven models were created to simulate IT filled with (model 2) calcium hydroxide (CH), (model 3) mineral trioxide aggregate (MTA), (model 4) Biodentine (B), (models 5 and 6) MTA plug and B plug without root-filling, (models 7 and 8) MTA plug and B plug with root-filling with composite restoration, and amputation by using (model 9) CH, (model 10) MTA, and (model 11) B. Materials and structures were assumed to be homogenous and isotropic. A 300 N load was applied to the models from the functional cusps and central fossa with a 135° angle. Cosmosworks structural analysis program was used. The results were presented considering the von Mises criteria, and the scale range was limited to 0-10 + MPa. CH use in comparison with temporary filling increased the stresses within the root. MTA filling showed less stresses when compared with B filling. MTA and B plug increased the stresses at apical and root; however, when the roots were filled using gutta-percha and the crowns were restored with composite resin, the stresses at the coronal side of the roots were reduced. The stresses were distributed more favorably in the models simulating CH, MTA, or B amputation. Amputation by using MTA and B showed similar stresses with natural tooth model. CH is not a favorable dressing material for IT when compared with MTA and B. MTA or B plug increases the stresses at apical, whereas root-filling reduces the stresses within the root. Amputation by using CH, MTA, and B in combination with composite resin restoration may save both the coronal and root structure of IT. Copyright © 2017

  4. Factorial analysis of variables influencing mechanical characteristics of a post used to restore a root filled premolar using the finite element stress analysis combined with the Taguchi method.

    Science.gov (United States)

    Wang, C H; Du, J K; Li, H Y; Chang, H C; Chen, K K

    2016-07-01

    To identify the contributions of various mechanical factors related to cast posts in a root filled tooth by integration of finite element analysis and the Taguchi method. The investigated factors included post-length (Post-L), post-diameter (Post-D), ferrule height (Ferrule-H) and periodontal bone loss (Bone-H). Three-dimensional finite element models of a mandibular premolar were developed to simulate a root filled tooth. For each investigated factor, three levels and values were selected, and based on a Taguchi orthogonal array, nine models were established. An inclination load of 100 N was applied on the buccal cusp tip, and the dentine peak von Mises stress was used as the evaluation index. Among the four investigated factors, Bone-H was the predominant mechanical factor, with a contribution of more than 97%. Among the other three controllable factors of post-design, Post-D was the primary contributing factor and was almost five times more substantial than the least contributing factor, Ferrule-H. Bone-H was the predominant factor influencing the stress of the dentine on a post-restored root filled tooth, followed by the Post-D, Post-L and Ferrule-H. For patients with severe periodontal bone loss, a large post-diameter is essential for endodontic post-restoration treatment. © 2015 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  5. Gestion du changement, gestion de projet : convergence - divergence. Cas des risques en conception et mise en place d'une organisation de management de l'environnement

    OpenAIRE

    Bassetti, Ann-Laure

    2002-01-01

    La mise en place d'une nouvelle organisation apparaît comme un moyen pour l'entreprise de répondre aux multiples pressions du milieu extérieur. Nous avons fait le choix de gérer ce travail sous la forme d'un projet : le projet de conception et de mise en place d'une nouvelle organisation. Nous associons la phase de conception à une approche amont du management des risques projet. Nous abordons la phase de mise en place par une approche originale de la mise en oeuvre du changement (alternance ...

  6. Effet de la mise en culture des forêts secondaires sur les ...

    African Journals Online (AJOL)

    L'impact de la mise en culture des forêts sur les peuplements de macroinvertébrés du sol a été étudié en moyenne Côte d'Ivoire avec pour objectif d'identifier les plus sensibles à la perturbation des forêts. Les macroinvertébrés du sol de parcelles de forêt secondaire et de cultures vivrières ont été échantillonnés en utilisant ...

  7. KariaNet : éclairages sur la mise en commun des connaissances ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    KariaNet est un réseau régional qui cherche à améliorer la mise en commun des connaissances sur l'agriculture et le développement rural afin d'aider les ... était la plus réussie, a contribué à la diffusion des expériences auprès des regroupements d'agriculteurs au Maroc et dans le milieu de la gestion de l'eau en Égypte.

  8. Mise en groupe, psychose et porosité des enveloppes psychiques

    OpenAIRE

    Vollon, Clarisse; Gimenez, Guy; Bonnet, Christian

    2015-01-01

    International audience; Nous proposons d’étudier les processus psychiques du thérapeute durant la période de mise en groupe dans le cadre d’un groupe psychanalytique de paroles mené dans un service d’ergo-sociothérapie avec des patients psychotiques adultes. Le but est de montrer que les premiers temps d’un groupe thérapeutique ont pour effet de modifier la texture des enveloppes psychiques du clinicien, qui vont tendre vers une plus grande porosité. Après avoir défini ce que nous entendons p...

  9. Problématique de mise en oeuvre du système de riziculture intensif ...

    African Journals Online (AJOL)

    Une enquête d'évaluation de la rentabilité économique en fonction de la gestion de la culture a été aussi réalisée. Les résultats montrent la problématique liée à la mise en oeuvre du SRI et son opportunité chez les riziculteurs. Une adaptation du SRI aux réalités socio-économiques et agroécologiques des riziculteurs ...

  10. Planification de la mise en place d'un Centre régional pour l ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Eric Smith. En octobre 2010, des intéressés de divers pays de l'Afrique de l'Ouest se sont réunis à Accra, au Ghana, afin de discuter de la mise en place d'un centre voué à la promotion de l'intégration régionale, de la bonne gouvernance et de la démocratie. Le Mécanisme africain d'évaluation par les pairs (MAEP) est un ...

  11. Mise-a-la-masse method in structure investigations of crystalline bedrock; Latauspotentiaalimenetelmae kiteisen kallion rakennetutkimuksissa

    Energy Technology Data Exchange (ETDEWEB)

    Paananen, M.

    1997-12-31

    In the work, the experience and results obtained in applying the mise-a-la-masse method in bedrock investigations for high- level nuclear waste disposal are presented. On the basis of extensive numerical modelling and qualitative examination, the following items are discussed: how the field measurements should be carried out, in which form the results should be presented and how a galvanic connection formed be a fracture zone can be observed from the results. This examination is valid for hole- to-surface (or vice versa) and crosshole measurements. 51 refs. Nuclear Waste Disposal Research.

  12. The effects of necrotic lesion size and orientation of the femoral component on stress alterations in the proximal femur in hip resurfacing - a finite element simulation.

    Science.gov (United States)

    Tai, Ching-Lung; Chen, Yung-Chou; Hsieh, Pang-Hsin

    2014-08-05

    Due to the advantages of its bone-conserving nature, hip resurface arthroplasty (HRA) has recently gained the interest of orthopedic surgeons for the treatment of young and active patients who have osteonerosis of the femoral head. However, in long-term follow-up studies after HRA, narrowing of the femoral neck has often been found, which may lead to fracture. This phenomenon has been attributed to the stress alteration (stress shielding). Studies addressing the effects of necrotic size and the orientation of the implant on stress alterations are lacking. Computed tomography images of a standard composite femur were used to create a three-dimensional finite-element (FE) intact femur model. Based on the intact model, FE models simulating four different levels of necrotic regions (0°, 60°, 100°, 115°) and three different implant insertion angles (varus 10°, neutral, valgus 10°) were created. The von Mises stress distributions and the displacement of the stem tip of each model were analyzed and compared for loading conditions that simulated a single-legged stance. Stress shielding occurred at the femoral neck after HRA. More severe stress shielding and an increased displacement of the stem tip were found for femoral heads that had a wider necrotic lesion. From a biomechanics perspective, the results were consistent with clinical evidence of femoral neck narrowing after HRA. In addition, a varus orientation of the implant resulted in a larger displacement of the stem tip, which could lead to an increased risk of implant loosening. A femoral head with a wide necrotic lesion combined with a varus orientation of the prosthesis increases the risk of femoral neck narrowing and implant loosening following HRA.

  13. Planung von CLIL-Unterricht

    Directory of Open Access Journals (Sweden)

    Josef Leisen

    2015-10-01

    Full Text Available Der Beitrag formuliert die Sprachlernbedingungen und die Leitlinien des Sprachlernens im Fach und nennt Merkmale des guten integrierten Fach- und Sprachlehrens. Ausgehend von den Sprachproblemen, die sich im CLIL-Unterricht auftun, wird der sprachsensible CLIL-Unterricht definiert, und es werden Anregungen zur Gestaltung gegeben. Sprachliche Standardsituationen umfassen die kommunikativen Situationen im CLIL-Unterricht, die beim fachlichen Lernen auftreten und von der CLIL-Lehrkraft professionell bewältigt werden müssen. Im Beitrag wird ein Lehr-Lern-Modell ausführlich beschrieben und erläutert. Die Steuerungen von Sprachlernprozessen im CLIL durch Aufgabenstellungen, Methoden-Werkzeuge, Moderation und Diagnose/Rückmeldung werden ausführlich beschrieben. Die Planung einer Lernlinie in sechs Schritten wird dargestellt und erläutert. Planungsraster für CLIL-Lernlinien schließen den Beitrag ab. The article sets out the conditions for language learning in general as well as guiding principles of language learning in the subject and puts forward criteria for successfully integrated content and language learning. Based on typical language problems arising in CLIL-classrooms, the language-sensitive CLIL-classroom is defined and organisational suggestions are given. Linguistic standard situations comprise the communicative situations in the CLIL-classroom which are encountered in subject-related learning and have to be professionally mastered by the CLIL-teacher. The article extensively describes and explains a model of teaching and learning that can be used for the CLIL-classroom. It gives detailed information on managing language learning processes in CLIL by means of tasks, resources and methods as well as discourse facilitation, evaluation and feedback. In addition, a six-step lesson unit is outlined and explained. The article concludes by giving a planning matrix for CLIL lesson units.

  14. Homoepitaxie von ZnO

    OpenAIRE

    Neumann, Christian

    2006-01-01

    Die Arbeit beschäftigt sich mit der homoepitaktischen Darstellung von ZnO-Dünnschichten. Die Arbeit beginnt mit einer theoretischen Betrachtung des Materialsystems und den daraus für eine erfolgreiche Epitaxie zu ziehenden Schlüssen. Es wurde eine Temperbehandlung zur Oberflächenmodifikation kommerziell erhältlicher ZnO-Einkristallsubstrate erarbeitet, die für eine erfolgreiche Epitaxie erforderlich ist. Im Anschluß daran wird die Entwicklung eines CVD-Prozesses mit metallischer Zin...

  15. Riidaja mõis / Elma von Stryk

    Index Scriptorium Estoniae

    Stryk, Elma von

    2006-01-01

    renoveerimise ootel barokne puithäärber (1762), kompleksi ümbritsev kivimüür, maakividest hobusetall, pargivaade, punastest tellistest neogooti stiilis kabel (1864), mis taastati von Strykkide perekonna toel. 11 ill.; fotod: Raivo Tasso; kabelis on Elma von Stryki loodud Kristust kujutav altarimaal

  16. Sorten- und Nachbaueignung von Hafer und Weizen

    OpenAIRE

    Spieß, Hartmut

    2000-01-01

    Der Beitrag gibt anhand alter und neuer Sortenvergleiche von Hafer und Weizen Einblick in die Problematik ökologischer Züchtung und Sortenwahl. Dabei geht es neben spezifischen Sorteneigenschaften um die Ausgewogenheit von Ertrags- und Qualitätsbildung im Verhältnis zur Pflanzengesundheit.

  17. Stress.

    Science.gov (United States)

    Chambers, David W

    2008-01-01

    We all experience stress as a regular, and sometimes damaging and sometimes useful, part of our daily lives. In our normal ups and downs, we have our share of exhaustion, despondency, and outrage--matched with their corresponding positive moods. But burnout and workaholism are different. They are chronic, dysfunctional, self-reinforcing, life-shortening habits. Dentists, nurses, teachers, ministers, social workers, and entertainers are especially susceptible to burnout; not because they are hard-working professionals (they tend to be), but because they are caring perfectionists who share control for the success of what they do with others and perform under the scrutiny of their colleagues (they tend to). Workaholics are also trapped in self-sealing cycles, but the elements are ever-receding visions of control and using constant activity as a barrier against facing reality. This essay explores the symptoms, mechanisms, causes, and successful coping strategies for burnout and workaholism. It also takes a look at the general stress response on the physiological level and at some of the damage American society inflicts on itself.

  18. The von Hippel Lindau tumor suppressor limits longevity.

    Science.gov (United States)

    Müller, Roman-Ulrich; Fabretti, Francesca; Zank, Sibylle; Burst, Volker; Benzing, Thomas; Schermer, Bernhard

    2009-12-01

    Many genes are responsible for the modulation of lifespan in model organisms. In addition to regulating adaptive biologic responses that control stress signaling and longevity, some of these genes participate in tumor formation. The mechanisms that determine longevity and link regulation of lifespan with tumorigenesis are poorly understood. Here, we show that the tumor suppressor von Hippel-Lindau (VHL), which has widely known roles in renal carcinogenesis and the formation of kidney cysts, controls longevity in Caenorhabditis elegans. Loss of vhl-1 significantly increased lifespan and resulted in accelerated basal signaling of the p38 mitogen-activated protein kinase PMK-3. Furthermore, the VHL-1 effect on the regulation of lifespan was independent of the insulin/IGF-1-like signaling pathway, suggesting a mechanism for stress resistance that controls both lifespan and tumorigenesis. These findings define VHL-1 as a player in longevity signaling and connect aging, regulation of lifespan, and stress responses with formation of renal cell carcinomas.

  19. MISE-EN-ABYME: THE PORTRAIT OF REMBRANDT IN THE CONFESSIONAL NOVEL ‘DANIEL MARTIN’ BY JOHN FOWLES (1977

    Directory of Open Access Journals (Sweden)

    Dzhumailo O.A.

    2013-03-01

    Full Text Available This article proposes the importance of mise-en-abyme inclusion into the artistic whole of the self-reflexive confessional novel Daniel Martin (1977 by John Fowles. It is argued that Rembrandt’s late self-portrait provokes ideas for the novel reading and manifests itself as an emblem of artistic authenticity. Analytical reading of the psychological and existentialist scope of mise-en-abyme also focuses on playful use of self-reflexive means (metalepsis, short circuit, mirror leitmotif, fragmentality, stylization and other means. All these are aligned with the idea of confessional lack of closure.

  20. Mise en abyme čtení v románech " Madam Bovaryová" a " Na ruby"

    OpenAIRE

    Sekerková, Danka

    2011-01-01

    Title of the thesis: Mise en abyme of the reading in novels "Madame Bovary" and "A Rebours". Keywords: literature, mímésis, anti-mímésis, reception of a literary work, reading, mise en abyme of reading (Metareading), reader, Metareader, fictional reality (fiction), objective reality (reality) and intertextuality. Abstract: The main subject of this diploma thesis is the reading of novels and its pernicious effect on a reader. This aspect is studied in the novels which involve the process of re...

  1. Jacob Stael von Holstein ja palladionism eesti arhitektuuris / Ants Hein

    Index Scriptorium Estoniae

    Hein, Ants, 1952-

    2005-01-01

    Sõjaväeinsenerist ja arhitektist Jacob Stael von Holsteinist (1628, Pärnu-1679), tema kavandatud hoonetest ja rollist 17. sajandi II poole arhitektuuris. Fabian von Ferseni Toompeal Lossiplatsil asunud elamust (lammutati 1894) ja Maardu mõisahoonest, Hans von Ferseni Mäo mõisahoonest Järvamaal, Otto Wilhelm von Ferseni majast Toompeal, Axel von Roseni majast Tallinnas Pikk t. 28 (1670-74), Otto Reinhold von Taube majast Tartus (hävinud), J. S. von Holsteini enda hoonetest: majast Tallinnas Toompea 1, Anija mõisahoonest, elamust Riias jm. Bibliograafia lk. 452

  2. Neues über das Tertiär von Java und die mesozoischen Schichten von West-Borneo

    NARCIS (Netherlands)

    Martin, K.

    1888-01-01

    Die Monographie, welche unter dem Titel Die Fossilien von Java herausgegeben wird ¹), ist so weit fortgeschritten, dass sich aus den in ihr beschriebenen Gastropoden bereits eine Anzahl von Schlussfolgerungen ableiten lässt, welche für die in Bearbeitung begriffene, geologische Karte von Java von

  3. Indikatorenbasierte Bewertung von Entwurfsentscheidungen auf Systemebene

    Science.gov (United States)

    Freier, M.; Wenzler, A.; Mayer, T.; Gerlach, J.; Rosenstiel, W.

    2013-07-01

    Bei dem Entwurf von anwendungsspezifischen integrierten Schaltungen muss ein Entwickler zusätzliche Funktionen integrieren und die zunehmende Komplexität bewältigen. Für die Reduzierung der Kosten bleibt weiterhin die Verkürzung der benötigten Entwicklungszeit ein Ziel. Ein entscheidender Faktor dabei ist die zuverlässige Absicherung von Entwurfsentscheidungen in einer frühen Entwurfsphase. In der vorliegenden Arbeit wird eine Methode vorgestellt, die eine Bewertung von Entwurfsentscheidungen bei Systemmodellen mittels automatisch ermittelter Indikatoren ermöglichen soll. Die Systemmodelle können mit der Entwurfsumgebung MATLAB/Simulink oder in SystemC beschrieben sein.

  4. The Digital Von Fahrenheid Pyramid

    Science.gov (United States)

    Bura, M.; Janowski, J.; Wężyk, P.; Zięba, K.

    2017-08-01

    3D Scanners Lab from Digital Humanities Laboratory at the University of Warsaw initiated the scientific project, the purpose of which was to call attention to systematically penetrated and devastated pyramid-shaped tomb from the XVIII/XIX century, of family von Fahrenheid in Rapa in Banie Mazurskie commune (NE Poland). By conducting a series of non-invasive studies, such as 3D inventory using terrestrial laser scanning (TLS), thermal imaging, georadar measurements (around and inside the tomb) and anthropological research of mummified remains as well - the complete dataset was collected. Through the integration of terrestrial (TLS) and airborne laser scanning (ALS) authors managed to analyse the surroundings of Fahrenheid pyriamid and influence of some objects (like trees) on the condition and visibility of the Pyramids in the landscape.

  5. Khazanah: Friedrich Karl von Savigny

    Directory of Open Access Journals (Sweden)

    Atip Latipulhayat

    2015-04-01

    Full Text Available Friedrich Karl von Savigny (1779-1861 adalah ahli hukum Jerman yang juga dianggap sebagai salah satu Bapak hukum Jerman. Savigny adalah tokoh mazhab sejarah (historical school jurisprudence yang dikembangkannya pada paruh pertama abad ke 19. Dia juga dianggap sebagai pelopor kajian mengenai relasi antara perkembangan hukum dan sosial. Sebagai seorang pemikir hukum yang senantiasa kreatif dalam membuat terobosan-terobosan (trail-blazing legal scientist, Savigny memberikan kontribusi penting dalam perkembangan ilmu hukum dan bahkan terhadap ilmu sosial. Dari sekian banyak kontribusinya antara lain teorinya mengenai kontinuitas antara institusi hukum saat ini dengan institusi hukum masa lalu, meletakkan fondasi bagi kajian sosiologi hukum, dan menegaskan mengenai urgensi metode historis dalam kajian hukum.

  6. Evaluierung und Entwicklung von Methoden zur automatisierten Erfassung von Waldstrukturen aus Daten flugzeuggetragener Fernerkundungssensoren

    OpenAIRE

    Heurich, Marco

    2006-01-01

    Auf Grund der rasanten technologischen Entwicklung im Bereich der Sensorik sowie der Computerhard- und -software haben sich in den letzten Jahren neue Perspektiven zur Erforschung von Wäldern ergeben. Im Rahmen dieser durch die High-Tech-Offensive Bayern geförderten Arbeit wurde deshalb untersucht, inwieweit sich der Einsatz neuer Technologien zur automatisierten Erfassung von Waldstrukturen eignet. Als Voraussetzung dafür wurde zunächst ein Referenzgebiet zum Testen von Fernerkundungssensore...

  7. Spezifische Bindung von Aluminium und Eisen an den kationenselektiven Kanal MppA von Microthrix parvicella

    OpenAIRE

    Knaf, Tobias

    2013-01-01

    Schwermetallsalze wie beispielsweise Aluminium- oder Eisensalze werden in der Abwasserbehandlung zur Prävention und Bekämpfung von Blähschlamm, Schwimmschlamm und Schaumbildung verwendet. Dadurch kann eine Verbesserung der Schlammabsetzeigenschaften im Nachklärbecken erreicht werden. Übermäßiges Wachstum des grampositiven Bakteriums Microthrix parvicella gilt dabei als Hauptursache von Schlammabsetzproblemen und kann ebenfalls durch die Dosierung von schwermetallhaltigen Flockungs- und Fällun...

  8. Das Tumorsuppressorprotein p53 - Rolle bei der Induktion von Apoptose und bei der Replikation von Adenoviren

    OpenAIRE

    Koch, Philipp

    2003-01-01

    Das Tumorsuppressorgen p53 gehört zu den zentralen Steuereinheiten von Proliferation und Wachstum in der Zelle. Mutationen und funktioneller Verlust bei diesem Protein ist eng mit der Entstehung maligner Tumoren assoziiert. So kann man in über 50% aller soliden Tumoren Mutationen von p53 nachweisen. Es vermittelt seine Funktion hauptsächlich durch transkriptionelle Aktivierung p53-responsiver Gene. Folge der Aktivierung von p53 is...

  9. Carbonate redistribution, element mobilisation and petroleum hydrocarbon migration in Posidonia shale (Hils basin, NW Germany) as a function of palaeotemperature load from the Vlotho mass; Karbonatumverteilung, Mobilisation von Elementen und Migration von Erdoel-Kohlenwasserstoffen im Posidonienschiefer (Hilsmulde, NW-Deutschland) in Abhaengigkeit von der Palaeotemperaturbeanspruchung durch das Massiv von Vlotho

    Energy Technology Data Exchange (ETDEWEB)

    Jochum, J.

    1993-04-01

    Temperature-controlled processes of carbonate redistribution, element mobilisation and petroleum hydrocarbon migration in the Posidonia shale of North West Germany (Lower Toarcian) were documented, and a statistical evaluation was made. The investigations focused on six Posidonia shales of the Hils basin which had been exposed to increasing palaeotemperature stress from SE to NW in the direction of the injected mass of Vlotho. According to earlier investigations, the mean values of vitrinite reflection in the six boreholes are between 0.48% Rm and 1.45% Rm. This corresponds to a maximum palaeotemperature of 93-190 C. (orig./EF) [Deutsch] Im Rahmen der vorliegenden Arbeit wurden temperaturgesteuerte Prozesse der Umverteilung von Karbonaten, der Mobilisation von Elementen und der Migration von Erdoel-Kohlenwasserstoffen im nordwestdeutschen Posidonienschiefer (Unteres Toarcium) dokumentiert und bilanziert. Gegenstand der Untersuchungen waren sechs Posidonienschieferprofile aus dem Bereich der Hilsmulde, die von SE and NW in Annaeherung an das Intrusivmassiv von Vlotho eine zunehmende Palaeotemperaturbeanspruchung erfahren haben. Frueheren Untersuchungen zufolge liegen die Mittelwerte der Vitrinitreflexion in den sechs Bohrungen zwischen 0,48% Rm und 1,45% Rm, was einem Bereich der maximal erreichten Palaeotemperatur zwischen ca. 93 C und ca. 190 C entspricht. (orig./EF)

  10. Ethnobotany of religious and supernatural beliefs of the Mising tribes of Assam with special reference to the 'Dobur Uie'

    Directory of Open Access Journals (Sweden)

    Pegu Shyamanta

    2011-06-01

    Full Text Available Abstract Assam is very rich in plant biodiversity as well as in ethnic diversity and has a great traditional knowledge base in plant resources. It is inhabited by the largest number of tribes and they lead an intricate life totally dependent on forest plants. The Mising is the major section and second largest tribal community of Assam and have a rich tradition of religion and culture. Their religious practices and beliefs are based on supernaturalism. A study of the plants related to magico religious beliefs in Dobur Uie of Mising is carried out. The results revealed the use of 30 plants belonging to 23 families. All plant species are used both in religious purpose as well as in the treatment of different ailments. Details of the uses of plants and conservational practices employed in Dobur Uie are provided. Our findings on the use of plants in Dobur Uie ritual reflect that some plants are facing problems for survival and they need urgent conservation before their elimination. Because this elimination may threat the rich tradition of Mising culture. Most of the plants that are domesticated for different rituals are almost same in all Mising populated areas.

  11. Supporting interoperability of collaborative networks through engineering of a service-based Mediation Information System (MISE 2.0)

    Science.gov (United States)

    Benaben, Frederick; Mu, Wenxin; Boissel-Dallier, Nicolas; Barthe-Delanoe, Anne-Marie; Zribi, Sarah; Pingaud, Herve

    2015-08-01

    The Mediation Information System Engineering project is currently finishing its second iteration (MISE 2.0). The main objective of this scientific project is to provide any emerging collaborative situation with methods and tools to deploy a Mediation Information System (MIS). MISE 2.0 aims at defining and designing a service-based platform, dedicated to initiating and supporting the interoperability of collaborative situations among potential partners. This MISE 2.0 platform implements a model-driven engineering approach to the design of a service-oriented MIS dedicated to supporting the collaborative situation. This approach is structured in three layers, each providing their own key innovative points: (i) the gathering of individual and collaborative knowledge to provide appropriate collaborative business behaviour (key point: knowledge management, including semantics, exploitation and capitalisation), (ii) deployment of a mediation information system able to computerise the previously deduced collaborative processes (key point: the automatic generation of collaborative workflows, including connection with existing devices or services) (iii) the management of the agility of the obtained collaborative network of organisations (key point: supervision of collaborative situations and relevant exploitation of the gathered data). MISE covers business issues (through BPM), technical issues (through an SOA) and agility issues of collaborative situations (through EDA).

  12. Accélérer la mise au point d'un vaccin contre le virus de la peste ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Accélérer la mise au point d'un vaccin contre le virus de la peste porcine africaine grâce à la biologie synthétique. 12 janvier 2018. Fonds d'innovation en vaccins pour le bétail. deux cochons. Photo : CRDI / Bartay ...

  13. Ethnobotany of religious and supernatural beliefs of the Mising tribes of Assam with special reference to the 'Dobur Uie'.

    Science.gov (United States)

    Sharma, Uma Kanta; Pegu, Shyamanta

    2011-06-02

    Assam is very rich in plant biodiversity as well as in ethnic diversity and has a great traditional knowledge base in plant resources. It is inhabited by the largest number of tribes and they lead an intricate life totally dependent on forest plants. The Mising is the major section and second largest tribal community of Assam and have a rich tradition of religion and culture. Their religious practices and beliefs are based on supernaturalism. A study of the plants related to magico religious beliefs in Dobur Uie of Mising is carried out. The results revealed the use of 30 plants belonging to 23 families. All plant species are used both in religious purpose as well as in the treatment of different ailments. Details of the uses of plants and conservational practices employed in Dobur Uie are provided. Our findings on the use of plants in Dobur Uie ritual reflect that some plants are facing problems for survival and they need urgent conservation before their elimination. Because this elimination may threat the rich tradition of Mising culture. Most of the plants that are domesticated for different rituals are almost same in all Mising populated areas.

  14. La mise en voix del Cantar del Mio Cid y el Códice de Vivar

    Directory of Open Access Journals (Sweden)

    Alejandro Higashi

    2007-11-01

    Full Text Available In the last years, the musical performance has taken an important place in the study of the mise en voix of the Cantar de Mio Cid. Although this perspective is laudable in many ways, I propose to take care on the textual and codicological plane, because many of the musical traces are lost for distinct reasons: the condition of the copy, finished according to the historiographical patterns of the medieval scriptorium; the indirect knowledge of the medieval epic music; the gaps in the understanding of how medieval cantillation was performed during public workship, in the laic or clerical life; the influence (or not of the medieval chant dialects (especially, mozarabic and eugenian chants, etc.

  15. How Is von Willebrand Disease Treated?

    Science.gov (United States)

    ... the condition. For example, the school nurse, teacher, daycare provider, coach, or any leader of afterschool activities ... MedlinePlus) Von Willebrand Disease (MedlinePlus) Building 31 31 Center Drive Bethesda, MD 20892 Learn more about getting ...

  16. How Is von Willebrand Disease Diagnosed?

    Science.gov (United States)

    ... the condition. For example, the school nurse, teacher, daycare provider, coach, or any leader of afterschool activities ... MedlinePlus) Von Willebrand Disease (MedlinePlus) Building 31 31 Center Drive Bethesda, MD 20892 Learn more about getting ...

  17. Johann Friedrich Wilhelm Adolf von Baeyer

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 19; Issue 6. Johann Friedrich Wilhelm Adolf von Baeyer: A Pioneer of Synthetic Organic Chemistry. Gopalpur Nagendrappa. General Article Volume 19 Issue 6 June 2014 pp 489-522 ...

  18. Genetics Home Reference: von Willebrand disease

    Science.gov (United States)

    ... Jun;5(6):1165-9. Citation on PubMed Kessler CM. Diagnosis and treatment of von Willebrand disease: ... consult with a qualified healthcare professional . About Selection Criteria for Links Data Files & API Site Map Customer ...

  19. Von Onlineplattformen und mittelalterlichen Märkten

    Directory of Open Access Journals (Sweden)

    Claudius Gräbner

    2017-12-01

    Full Text Available Mit der zunehmenden Digitalisierung und Vernetzung ökonomischer Systeme haben plattformbasierte Interaktionsbeziehungen stark an Bedeutung gewonnen. Hier werden zwei oder mehr Nutzungsgruppen durch eine dritte Seite, die Plattform, zusammengebracht. Die Interaktion wird in solchen zweiseitigen Märkten von den Plattformbetreibern kontrolliert. Kreditkartensysteme, Softwaremärkte oder werbefinanzierte Online-Communities stellen typische Beispiele dar. Da die Analyse von zweiseitigen Märkten mit Gleichgewichtsmodellen aufgrund der algebraischen Struktur des Problems in der Regel nicht praktikabel ist, präsentieren wir im vorliegenden Beitrag ein agentenbasiertes Modell, welches in einem kürzlich erschienenen Artikel ausführlicher diskutiert wird. Anhand von illustrativen Beispielen verdeutlichen wir die Implikationen eines agentenbasierten Ansatzes für die Innovationsökonomik im Allgemeinen und das Studium von Technologieentwicklung im Besonderen.

  20. Stress and displacement patterns in the craniofacial skeleton with rapid maxillary expansion-a finite element method study.

    Science.gov (United States)

    Priyadarshini, J; Mahesh, C M; Chandrashekar, B S; Sundara, Abhishek; Arun, A V; Reddy, Vinay P

    2017-12-01

    Rapid maxillary expansion (RME), indicated in the treatment of maxillary deficiency directs high forces to maxillary basal bone and to other adjacent skeletal bones. The aim of this study is to (i) evaluate stress distribution along craniofacial sutures and (ii) study the displacement of various craniofacial structures with rapid maxillary expansion therapy by using a Finite Element model. An analytical model was developed from a dried human skull of a 12 year old male. CT scan images of the skull were taken in axial direction parallel to the F-H plane at 1 mm interval, processed using Mimics software, required portion of the skull was exported into stereo-lithography model. ANSYS software was used to solve the mathematical equation. Contour plots of the displacement and stresses were obtained from the results of the analysis performed. At Node 47005, maximum X-displacement was 5.073 mm corresponding to the incisal edge of the upper central incisor. At Node 3971, maximum negative Y-displacement was -0.86 mm which corresponds to the anterior zygomatic arch, indicating posterior movement of craniofacial complex. At Node 32324, maximum negative Z-displacement was -0.92 mm representing the anterior and deepest convex portion of the nasal septum; indicating downward displacement of structures medial to the area of force application. Pyramidal displacement of maxilla was evident. Apex of pyramid faced the nasal bone and base was located on the oral side. Posterosuperior part of nasal cavity moved minimally in lateral direction and width of nasal cavity at the floor of the nose increased, there was downward and forward movement of maxilla with a tendency toward posterior rotation. Maximum von Mises stresses were found along midpalatal, pterygomaxillary, nasomaxillary and frontomaxillary sutures.

  1. Stress and displacement patterns in the craniofacial skeleton with rapid maxillary expansion—a finite element method study

    Directory of Open Access Journals (Sweden)

    J. Priyadarshini

    2017-07-01

    Full Text Available Abstract Background Rapid maxillary expansion (RME, indicated in the treatment of maxillary deficiency directs high forces to maxillary basal bone and to other adjacent skeletal bones. The aim of this study is to (i evaluate stress distribution along craniofacial sutures and (ii study the displacement of various craniofacial structures with rapid maxillary expansion therapy by using a Finite Element model. Methods An analytical model was developed from a dried human skull of a 12 year old male. CT scan images of the skull were taken in axial direction parallel to the F-H plane at 1 mm interval, processed using Mimics software, required portion of the skull was exported into stereo-lithography model. ANSYS software was used to solve the mathematical equation. Contour plots of the displacement and stresses were obtained from the results of the analysis performed. Results At Node 47005, maximum X-displacement was 5.073 mm corresponding to the incisal edge of the upper central incisor. At Node 3971, maximum negative Y-displacement was -0.86 mm which corresponds to the anterior zygomatic arch, indicating posterior movement of craniofacial complex. At Node 32324, maximum negative Z-displacement was -0.92 mm representing the anterior and deepest convex portion of the nasal septum; indicating downward displacement of structures medial to the area of force application. Conclusions Pyramidal displacement of maxilla was evident. Apex of pyramid faced the nasal bone and base was located on the oral side. Posterosuperior part of nasal cavity moved minimally in lateral direction and width of nasal cavity at the floor of the nose increased, there was downward and forward movement of maxilla with a tendency toward posterior rotation. Maximum von Mises stresses were found along midpalatal, pterygomaxillary, nasomaxillary and frontomaxillary sutures.

  2. Ist Pop die Volksmusik von heute?

    OpenAIRE

    Arbeitskreis Studium Populärer Musik

    1986-01-01

    Zugegeben, die Frage, ob Pop die Volksmusik von heute sei, ist provokant. Genau das war beabsichtigt. Sehr schnell erhielten wir auf unser Vorhaben, ein Seminar zu diesem Thema zu veranstalten, eine Vielzahl von Rückmeldungen. Pop-, Rock- und Jazzspezialisten, Musikwissenschaftler und Musikotiunologen fühlten sich animiert, Stellung zu beziehen und ein Referat zu halten. Intensive Diskussionen schlossen sich an, beflügelt auch durch die ansprechende Atmosphdre in der stil...

  3. Begehrte Körper jenseits von Geschlecht?

    Directory of Open Access Journals (Sweden)

    Corinna Tomberger

    2001-03-01

    Full Text Available Obwohl die visuelle Konstruktion des männlichen Körpers im Mittelpunkt von Daniel Wildmanns Studie steht, gelingt es ihm paradoxerweise, die Kategorie Geschlecht weitgehend zu ignorieren. In seiner Analyse des Films Olympia von Leni Riefenstahl zeigt der Autor auf, wie der ‚arische‘ Körper als Objekt des Begehrens für das Publikum entworfen wird.

  4. Dr. von Braun With German Rocket Experimenters

    Science.gov (United States)

    1930-01-01

    Dr. von Braun was among a famous group of rocket experimenters in Germany in the 1930s. This photograph is believed to be made on the occasion of Herman Oberth's Kegelduese liquid rocket engine being certified as to performance during firing. From left to right are R. Nebel, Dr. Ritter, Mr. Baermueller, Kurt Heinish, Herman Oberth, Klaus Riedel, Wernher von Braun, and an unidentified person.

  5. 50th birthday of Christian von Ferber

    Directory of Open Access Journals (Sweden)

    2011-06-01

    Full Text Available On May 15, 2011 Christian von Ferber - member of the Editorial Board of "Condensed Matter Physics" and renowned expert in the fields of soft matter physics and complex systems - celebrated his 50th birthday. The Editorial board of CMP, colleagues and friends warmy congratulate Christian von Ferber and wish him and his family continuing good health and to enjoy many adventures and discoveries in his future scientific travels!

  6. Dr. von Braun With Management Team

    Science.gov (United States)

    1961-01-01

    Dr. von Braun is shown in this photograph, which was probably taken in the early 1960s, with members of his management team. Pictured from left to right are, Werner Kuers, Director of the Manufacturing Engineering Division; Dr. Walter Haeussermarn, Director of the Astrionics Division; Dr. William Mrazek, Propulsion and Vehicle Engineering Division; Dr. von Braun; Dieter Grau, Director of the Quality Assurance Division; Dr. Oswald Lange, Director of the Saturn Systems Office; and Erich Neubert , Associate Deputy Director for Research and Development.

  7. Hullud päevad von Krahlis

    Index Scriptorium Estoniae

    2006-01-01

    Von Krahli Teatris mängitakse neil päevi neli korda Peeter Jalaka lavastuses Tõnu Kõrvitsa kammeroopereid "Tuliaed" ja "Mu luiged, mu mõtted", mille aluseks on luuletaja Marie Heibergi saatus. Libreto autor on Maarja Kangro. Kammerooperid tulevad lavale Von Krahli Teatri ja Nargen Opera koostöös. Esitavad Kädy Plaas, Helen Lokuta, Nargen Opera koor ja Tallinna Kammerorkester, dirigent Tõnu Kaljuste

  8. Visualisierung von typisierten Links in Linked Data

    Directory of Open Access Journals (Sweden)

    Georg Neubauer

    2017-09-01

    Full Text Available Das Themengebiet der Arbeit behandelt Visualisierungen von typisierten Links in Linked Data. Die wissenschaftlichen Gebiete, die im Allgemeinen den Inhalt des Beitrags abgrenzen, sind das Semantic Web, das Web of Data und Informationsvisualisierung. Das Semantic Web, das von Tim Berners Lee 2001 erfunden wurde, stellt eine Erweiterung zum World Wide Web (Web 2.0 dar. Aktuelle Forschungen beziehen sich auf die Verknüpfbarkeit von Informationen im World Wide Web. Um es zu ermöglichen, solche Verbindungen wahrnehmen und verarbeiten zu können sind Visualisierungen die wichtigsten Anforderungen als Hauptteil der Datenverarbeitung. Im Zusammenhang mit dem Sematic Web werden Repräsentationen von zuhammenhängenden Informationen anhand von Graphen gehandhabt. Der Grund des Entstehens dieser Arbeit ist in erster Linie die Beschreibung der Gestaltung von Linked Data-Visualisierungskonzepten, deren Prinzipien im Rahmen einer theoretischen Annäherung eingeführt werden. Anhand des Kontexts führt eine schrittweise Erweiterung der Informationen mit dem Ziel, praktische Richtlinien anzubieten, zur Vernetzung dieser ausgearbeiteten Gestaltungsrichtlinien. Indem die Entwürfe zweier alternativer Visualisierungen einer standardisierten Webapplikation beschrieben werden, die Linked Data als Netzwerk visualisiert, konnte ein Test durchgeführt werden, der deren Kompatibilität zum Inhalt hatte. Der praktische Teil behandelt daher die Designphase, die Resultate, und zukünftige Anforderungen des Projektes, die durch die Testung ausgearbeitet wurden.

  9. Influence of microthreads and platform switching on stress distribution in bone using angled abutments.

    Science.gov (United States)

    Ferraz, Cacilda Cunha; Anchieta, Rodolfo Bruniera; de Almeida, Erika Oliveira; Freitas, Amilcar Chagas; Ferraz, Fábio Cunha; Machado, Lucas Silveira; Rocha, Eduardo Passos

    2012-10-01

    To evaluate the stress distribution in peri-implant bone by simulating the effect of an implant with microthreads and platform switching on angled abutments through tridimensional finite element analysis. The postulated hypothesis was that the presence of microthreads and platform switching would reduce the stress concentration in the cortical bone. Four mathematical models of a central incisor supported by an implant (5.0 mm × 13 mm) were created in which the type of thread surface in the neck portion (microthreaded or smooth) and the diameter of the angled abutment connection (5.0 and 4.1mm) were varied. These models included the RM (regular platform and microthreads), the RS (regular platform and smooth neck surface), the SM (platform switching and microthreads), and the SS (platform switching and smooth neck). The analysis was performed using ANSYS Workbench 10.0 (Swanson Analysis System). An oblique load (100N) was applied to the palatine surface of the central incisor. The bone/implant interface was considered to be perfectly integrated. Values for the maximum (σ(max)) and minimum (σ(min)) principal stress, the equivalent von Mises stress (σ(vM)), and the maximum principal elastic strain (ɛ(max)) for cortical and trabecular bone were obtained. For the cortical bone, the highest σ(max) (MPa) were observed for the RM (55.1), the RS (51.0), the SM (49.5), and the SS (44.8) models. The highest σ(vM) (MPa) were found for the RM (45.4), the SM (42.1), the RS (38.7), and the SS models (37). The highest values for σ(min) were found for the RM, SM, RS and SS models. For the trabecular bone, the highest σ(max) values (MPa) were observed in the RS model (6.55), followed by the RM (6.37), SS (5.6), and SM (5.2) models. The hypothesis that the presence of microthreads and a switching platform would reduce the stress concentration in the cortical bone was partially rejected, mainly because the microthreads increased the stress concentration in cortical bone. Only

  10. Stress distribution of single-implant-retained overdenture reinforced with a framework: A finite element analysis study.

    Science.gov (United States)

    Amaral, Camilla F; Gomes, Rafael S; Rodrigues Garcia, Renata C M; Del Bel Cury, Altair A

    2017-09-28

    Studies have demonstrated the effectiveness of a single-implant-retained mandibular overdenture for elderly patients with edentulism. However, due to the high concentration of stress around the housing portion of the single implant, this prosthesis tends to fracture at the anterior region more than the 2-implant-retained mandibular overdenture. The purpose of this finite-element analysis study was to evaluate the stress distribution in a single-implant-retained mandibular overdenture reinforced with a cobalt-chromium framework, to minimize the incidence of denture base fracture. Two 3-dimensional finite element models of mandibular overdentures supported by a single implant with a stud attachment were designed in SolidWorks 2013 software. The only difference between the models was the presence or absence of a cobalt-chromium framework at the denture base between canines. Subsequently, the models were imported into the mathematical analysis software ANSYS Workbench v15.0. A mesh was generated with an element size of 0.7 mm and submitted to convergence analysis before mechanical simulation. All materials were considered to be homogeneous, isotropic, and linearly elastic. A 100-N load was applied to the incisal edge of the central mandibular incisors at a 30-degree angle. Maximum principal stress was calculated for the overdenture, von Mises stress was calculated for the attachment and implant, and minimum principal stress was calculated for cortical and cancellous bone. In both models, peak stress on the overdenture was localized at the anterior intaglio surface region around the implant. However, the presence of the framework reduced the stress by almost 62% compared with the overdenture without a framework (8.7 MPa and 22.8 MPa, respectively). Both models exhibited similar stress values in the attachment, implant, and bone. A metal framework reinforcement for a single-implant-retained mandibular overdenture concentrates less stress through the anterior area of the

  11. A comparison of stresses in molar teeth restored with inlays and direct restorations, including polymerization shrinkage of composite resin and tooth loading during mastication.

    Science.gov (United States)

    Dejak, Beata; Młotkowski, Andrzej

    2015-03-01

    Polymerization shrinkage of composites is one of the main causes of leakage around dental restorations. Despite the large numbers of studies there is no consensus, what kind of teeth reconstruction--direct or indirect composite restorations are the most beneficial and the most durable. The aim was to compare equivalent stresses and contact adhesive stresses in molar teeth with class II MOD cavities, which were restored with inlays and direct restorations (taking into account polymerization shrinkage of composite resin) during simulated mastication. The study was conducted using the finite elements method with the application of contact elements. Three 3D models of first molars were created: model A was an intact tooth; model B--a tooth with a composite inlay, and model C--a tooth with a direct composite restoration. Polymerization linear shrinkage 0.7% of a direct composite restoration and resin luting cement was simulated (load 1). A computer simulation of mastication was performed (load 2). In these 2 situations, equivalent stresses according to the modified von Mises criterion (mvM) in the materials of mandibular first molar models with different restorations were calculated and compared. Contact stresses in the luting cement-tooth tissue adhesive interface around the restorations were also assessed and analyzed. Equivalent stresses in a tooth with a direct composite restoration (the entire volume of which was affected by polymerization shrinkage) were many times higher than in the tooth restored with a composite inlay (where shrinkage was present only in a thin layer of the luting cement). In dentin and enamel the stress values were 8-14 times higher, and were 13 times higher in the direct restoration than in the inlay. Likewise, contact stresses in the adhesive bond around the direct restoration were 6.5-7.7 times higher compared to an extraorally cured restoration. In the masticatory simulation, shear contact stresses in the adhesive bond around the direct

  12. Being stressed and active!? An analysis of different aspects of the relationship between physical activity, individual perceived stress, and individual health

    OpenAIRE

    Reiner, Miriam

    2014-01-01

    Die sportwissenschaftliche Forschung zeigt deutlich, dass Sport und körperliche Aktivität positive Effekte für die Gesundheit haben, im Gegensatz dazu aber erlebter Stress negative Folgen hat. Es stellt sich die Frage, welche Rollen und Effekte Sport im Stress-Gesundheit Kontext spielen kann. In drei Studien wurde der Moderatoreffekt von Sport auf den Zusammenhang zwischen Stress und Beschwerden sowie der Effekt von erlebtem Stress auf die Sportaktivität selbst untersucht.

  13. Modeling and stress analyses of a normal foot-ankle and a prosthetic foot-ankle complex.

    Science.gov (United States)

    Ozen, Mustafa; Sayman, Onur; Havitcioglu, Hasan

    2013-01-01

    Total ankle replacement (TAR) is a relatively new concept and is becoming more popular for treatment of ankle arthritis and fractures. Because of the high costs and difficulties of experimental studies, the developments of TAR prostheses are progressing very slowly. For this reason, the medical imaging techniques such as CT, and MR have become more and more useful. The finite element method (FEM) is a widely used technique to estimate the mechanical behaviors of materials and structures in engineering applications. FEM has also been increasingly applied to biomechanical analyses of human bones, tissues and organs, thanks to the development of both the computing capabilities and the medical imaging techniques. 3-D finite element models of the human foot and ankle from reconstruction of MR and CT images have been investigated by some authors. In this study, data of geometries (used in modeling) of a normal and a prosthetic foot and ankle were obtained from a 3D reconstruction of CT images. The segmentation software, MIMICS was used to generate the 3D images of the bony structures, soft tissues and components of prosthesis of normal and prosthetic ankle-foot complex. Except the spaces between the adjacent surface of the phalanges fused, metatarsals, cuneiforms, cuboid, navicular, talus and calcaneus bones, soft tissues and components of prosthesis were independently developed to form foot and ankle complex. SOLIDWORKS program was used to form the boundary surfaces of all model components and then the solid models were obtained from these boundary surfaces. Finite element analyses software, ABAQUS was used to perform the numerical stress analyses of these models for balanced standing position. Plantar pressure and von Mises stress distributions of the normal and prosthetic ankles were compared with each other. There was a peak pressure increase at the 4th metatarsal, first metatarsal and talus bones and a decrease at the intermediate cuneiform and calcaneus bones, in

  14. Privatiserung von Geschichte. Probleme einer differenzierten Aufarbeitung

    Directory of Open Access Journals (Sweden)

    Birthe Kundrus

    2000-11-01

    Full Text Available Ausgangspunkt der Untersuchung von Vera Neumann ist die These, daß im Krieg Erlebtes und Erlittenes in den Wiederaufbau- und Wirtschaftswunderjahren Westdeutschlands einem Thematisierungstabu unterlegen sei. Anhand von 50 Interviews, die in den 80er Jahren im Rahmen des von Lutz Niethammer geleiteten Projekts „Lebensgeschichte und Sozialgeschichte im Ruhrgebiet 1930–1960“ (LUSIR entstanden sind und die sie jetzt anhand der Tonbandprotokolle und Abschriften ein zweites Mal auswertet, möchte die Historikerin diese Verschüttungen aufspüren. Im Anschluß an Niethammers These der „Privatisierung von Geschichte“ will sie zeigen, daß seelische und körperliche Kriegsfolgen wie Deprivations- und Überlastungsgefühle, der Verlust von Angehörigen und Kriegsbeschädigungen „privatisiert“, d.h. an die Familien übertragen wurden. Dort seien dann in erster Linie die weiblichen Familienmitglieder mit der Versorgungs- und Pflegearbeit konfrontiert worden. An vier Fallbeispiele schließt sich eine detaillierte Auswertung des gesamten Interviewmaterials an. Diesen Teilen folgt ein Abschnitt zur staatlichen Kriegsopferversorgung in der frühen Bundesrepublik.

  15. An MRI Von Economo - Koskinas atlas.

    Science.gov (United States)

    Scholtens, Lianne H; de Reus, Marcel A; de Lange, Siemon C; Schmidt, Ruben; van den Heuvel, Martijn P

    2016-12-28

    The cerebral cortex displays substantial variation in cellular architecture, a regional patterning that has been of great interest to anatomists for centuries. In 1925, Constantin von Economo and George Koskinas published a detailed atlas of the human cerebral cortex, describing a cytoarchitectonic division of the cortical mantle into over 40 distinct areas. Von Economo and Koskinas accompanied their seminal work with large photomicrographic plates of their histological slides, together with tables containing for each described region detailed morphological layer-specific information on neuronal count, neuron size and thickness of the cortical mantle. Here, we aimed to make this legacy data accessible and relatable to in vivo neuroimaging data by constructing a digital Von Economo - Koskinas atlas compatible with the widely used FreeSurfer software suite. In this technical note we describe the procedures used for manual segmentation of the Von Economo - Koskinas atlas onto individual T1 scans and the subsequent construction of the digital atlas. We provide the files needed to run the atlas on new FreeSurfer data, together with some simple code of how to apply the atlas to T1 scans within the FreeSurfer software suite. The digital Von Economo - Koskinas atlas is easily applicable to modern day anatomical MRI data and is made publicly available online. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Doença de von Willebrand e anestesia Enfermedad de von Willebrand y anestesia Von Willebrand's disease and anesthesia

    Directory of Open Access Journals (Sweden)

    Fabiano Timbó Barbosa

    2007-06-01

    Full Text Available JUSTIFICATIVA E OBJETIVOS: A doença de von Willebrand ocorre devido à mutação no cromossomo 12 e é caracterizada por deficiência qualitativa ou quantitativa do fator de von Willebrand. A diversidade de mutações leva ao aparecimento das mais variadas manifestações clínicas possibilitando a divisão dos pacientes em vários tipos e subtipos clínicos. A coagulopatia se manifesta basicamente através da disfunção plaquetária associada à diminuição dos níveis séricos do fator VIII coagulante. O objetivo dessa revisão foi mostrar os cuidados relacionados aos pacientes portadores da doença de von Willebrand durante o período perioperatório. CONTEÚDO: Foram definidas as características da doença de von Willebrand quanto à fisiopatologia, à classificação, ao diagnóstico laboratorial, ao tratamento atual e aos cuidados com o manuseio do paciente no período perioperatório. CONCLUSÕES: A doença de von Willebrand é o distúrbio hemorrágico hereditário mais comum, porém ela é subdiagnosticada pela complexidade da própria doença. A correta classificação do paciente, o uso apropriado da desmopressina e a transfusão do fator de von Willebrand são medidas fundamentais para a realização do procedimento anestésico bem-sucedido.JUSTIFICATIVA Y OBJETIVOS: La enfermedad de von Willebrand ocurre debido a la mutación en el cromosoma 12 y se caracteriza por la deficiencia cualitativa o cuantitativa del factor de von Willebrand. La diversidad de mutaciones conlleva al aparecimiento de las más variadas manifestaciones clínicas posibilitando la división de los pacientes en varios tipos y subtipos clínicos. La coagulopatía se manifiesta básicamente a través de la disfunción plaquetaria asociada con la disminución de los niveles séricos del factor VIII coagulante. El objetivo de esa revisión fue mostrar los cuidados relacionados con las pacientes portadoras de la enfermedad de von Willebrand durante el per

  17. Von der Universitätsbibliothek Regensburg zum Bayerischen Bibliotheksverbund

    OpenAIRE

    Frankenberger, Rudolf

    1989-01-01

    Von der Universitätsbibliothek Regensburg zum Bayerischen Bibliotheksverbund : d. Entwicklung d. Bayer. Bibliotheksverbundes. - In: Bibliothekslandschaft Bayern : Festschr. für Max Pauer zum 65. Geburtstag / hrsg. von Paul Niewalda. - Wiesbaden : Harrassowitz, 1989. - S. 84-96

  18. Kerttu Wagner. Die historischen romane von Jaan Kross / Wolfgang Drechsler

    Index Scriptorium Estoniae

    Drechsler, Wolfgang, 1963-

    2001-01-01

    Arvustus: Wagner, Kerttu. Die historischen Romane von Jaan Kross : am Beispiel einer Untersuchung der deutschen und englischen Übersetzungen von "Professor Martensi ärasõit" (1984). Frankfurt am Main [etc.] : P. Lang, 2001.

  19. Mise en suspension du pollen par les abeilles et incidence de ce pollen sur la fécondation

    OpenAIRE

    Pierre, Justine; Vaissière, Bernard; Vallée, Patrick; RENARD, Michel

    2002-01-01

    Le transfert indirect du pollen par les abeilles, qui résulterait de la mise en suspension du pollen dans l'air sans contact avec les surfaces stigmatiques, a été suggéré plusieurs fois dans la littérature, mais jamais démontré. On sait que le pollen de colza n'est pas pulvérulent et est a priori peu adapté au transport aérien. Notre objectif était donc de savoir si les abeilles participent à la mise en suspension de ce pollen et si le pollen ainsi libéré contribue à la pollinisation. L'expér...

  20. Data processing for the mise-a-la-masse survey; Ryuden den`iho tansa no data shori

    Energy Technology Data Exchange (ETDEWEB)

    Hashimoto, K.; Mizunaga, H.; Ushijima, K. [Kyushu University, Fukuoka (Japan). Faculty of Engineering; Kaieda, H. [Central Research Institute of Electric Power Industry, Tokyo (Japan)

    1996-10-01

    Data processing method was studied for mise-a-la-masse survey. Mise-a-la-masse method using wells as current sources measures resultant ground surface potential difference, and detects underground local resistivity anomaly. To extract resistivity anomaly largely different from surroundings, the anomaly is extracted as difference between the estimated value of regular resistivity structure (background) and potential difference or apparent resistivity. The following three approximations were attempted to estimate the background: the theoretical equation assuming isotropic homogeneous resistivity structure, that assuming horizontal multi-layered structure and the exponential function of distance from linear electrode for apparent resistivity, and these were compared with each other by numerical model experiment. The data processing method which determines the resistivity structure of the background and the residual of apparent resistivity distribution by inversion analysis using the above second equation, could precisely extract local resistivity anomaly, and estimate the depth distribution of resistivity. 5 refs., 10 figs., 2 tabs.

  1. Gemeinsam hilfreich oder einsam lästig? Beurteilung von praktikumsbegleitenden Weblogs von angehenden Lehrpersonen

    Directory of Open Access Journals (Sweden)

    Nives Egger

    2017-02-01

    Full Text Available Weblogs werden an Hochschulen vermehrt zur Unterstützung von Lern- und Reflexionsprozessen eingesetzt, in der Lehrer/innenbildung auch zunehmend während der berufspraktischen Ausbildung. Die Studierenden beurteilen den Einsatz von Weblogs jedoch unterschiedlich. Dabei ist wenig bekannt, welchen Einfluss die Vergabe und das Erhalten von Peerfeedback auf den Beurteilungsprozess von praktikumsbegleitenden Weblogs sowie auf den Umfang von Blogpostings haben. Im folgenden Beitrag wird dieser Frage mittels einer Befragung von 74 angehenden Lehrpersonen nachgegangen, die praktikumsbegleitende Weblogs mit oder ohne Peerfeedback nutzten, um über herausfordernde Ereignisse im Praktikum zu reflektieren. Die Ergebnisse zeigen, dass Studierende, die Peerfeedback erhielten und andere Blogbeiträge kommentierten, den Weblogeinsatz nützlicher einschätzen sowie eine höhere Motivation und positivere Einstellung gegenüber den Einsatz von Weblogs aufweisen als Studierende, die ohne Peerfeedback bloggen. Keinen Einfluss hat Peerfeedback auf den Umfang der Blogbeiträge und auf die dafür aufgewendete Zeit.

  2. Mise en oeuvre de l'initiative Données probantes et systèmes de ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    L'initiative Données probantes et systèmes de santé au Nigeria (NEHSI) est mené en collaboration par le CRDI, l'Agence canadienne de développement international (ACDI) et le gouvernement du Nigeria. Elle a été mise sur pied en 2004 après que le Nigeria se soit engagé à effectuer une réforme de son secteur de la ...

  3. Stress distribution analysis during an intermaxillary dysjunction: A 3-D FEM study of an adult human skull.

    Science.gov (United States)

    Baldawa, Rahul Shyamsunder; Bhad, Wasundhara Ashok

    2011-01-01

    With the increased interest in adult orthodontics, maxillary width problems in the nongrowing patients have been encountered with greater frequency. In view of the negative outlook for successful nonsurgical palatal expansion in adult patients it seemed appropriate to evaluate the biomechanical effects of nonsurgical rapid maxillary expansion (RME) in adults using the finite element method (FEM). To evaluate the biomechanical effects of RME on the craniofacial complex as applied to three-dimensional (3D) model of an adult human skull using the finite element method. The Department of Orthodontics and Dentofacial Orthopedics at Government Dental College and Hospital, Nagpur. The study was done on an analytical model developed from a dry human skull of an adult female with an approximate age of 20 years. A 3D finite element analysis of the craniofacial complex was developed from sequential computed tomography scan images. Known transversal (X) displacement with magnitudes of 1, 3, and 5 mm were applied and the displacement and Von-Mises stresses in different planes were studied on different nodes located at various structures of the craniofacial complex. Transverse orthopedic forces not only produced an expansive force at the intermaxillary suture but also high forces on various structures of the craniofacial complex, particularly at the base of the sphenoid bone and frontal process of the zygomatic bone. Lateral bending of the free ends of the pterygoid plates were noted. RME must be used judiciously in adults because of its far-reaching effects involving heavy stresses being noted at the sphenoid bone, zygomatic bone, nasal bone, and their adjacent sutures.

  4. Polylaktidbeschichtung zur antithrombogenen Ausrüstung von Biomaterialien

    OpenAIRE

    Mebus, Siegrun

    2007-01-01

    In der Klinik etablierte Biomaterialien wurden mit einer Polylaktidbeschichtung und eingearbeiteten Antikoagulanzien ausgerüstet. Die mit einem in-vitro-Modell erarbeiteten Daten zeigen, daß der Arzneistoffträger innerhalb von 90 Tagen nicht abgebaut wurde. Die Freisetzung der Arzneistoffe erfolgte abhängig von deren Konzentration und dem Mischungsverhältnis von Iloprost und Hirudin. Iloprost beeinflußt die Freisetzungsrate von PEG-Hirudin bzw. r-Hirudin. Es konnte mit mikrobiologischen Metho...

  5. Nutzung der Eisenkorrosion zur Entfernung von Arsen aus Trinkwasser

    OpenAIRE

    Karschunke, Karsten

    2005-01-01

    In dieser Arbeit werden experimentelle Untersuchungen zur Nutzung von Eisenkorrosionsprozessen zur Entfernung von Arsen aus Trinkwasser vorgestellt. Auch in geringen Konzentrationen stellt diese Verunreinigung auf Grund der krebserregenden Wirkung von Arsen langfristig eine Gefahr für die menschliche Gesundheit dar. Verschiedene Entfernungsmethoden sind bekannt und in der Praxis der Trinkwasseraufbereitung bewährt, beispielsweise Flockungsverfahren unter Einsatz von Eisensalzen oder die Adsor...

  6. Liouville-von Neumann molecular dynamics.

    Science.gov (United States)

    Jakowski, Jacek; Morokuma, Keiji

    2009-06-14

    We present a novel first principles molecular dynamics scheme, called Liouville-von Neumann molecular dynamics, based on Liouville-von Neumann equation for density matrices propagation and Magnus expansion of the time-evolution operator. The scheme combines formally accurate quantum propagation of electrons represented via density matrices and a classical propagation of nuclei. The method requires a few iterations per each time step where the Fock operator is formed and von Neumann equation is integrated. The algorithm (a) is free of constraint and fictitious parameters, (b) avoids diagonalization of the Fock operator, and (c) can be used in the case of fractional occupation as in metallic systems. The algorithm is very stable, and has a very good conservation of energy even in cases when a good quality conventional Born-Oppenheimer molecular dynamics trajectories is difficult to obtain. Test simulations include initial phase of fullerene formation from gaseous C(2) and retinal system.

  7. Gasification of liquid manure; Vergasung von Guelle

    Energy Technology Data Exchange (ETDEWEB)

    Gudenau, H.W.; Hoberg, H.; Hirsch, U. [Technische Hochschule Aachen (Germany). Inst. fuer Eisenhuettenkunde

    1996-12-31

    The potential of thermal use of liquid manure is investigated. It is recommended to separate the liquid and solid fraction. While the liquid fraction can be used as fertilizer, the solid fraction can be used for generating a fuel gas for combined heat and power generation. (orig) [Deutsch] Die Untersuchungen haben ergeben, dass in der thermischen Verwertung von Guelle ein bisher nur wenig genutztes Potential vorliegt. Die zum Anbau von Getreide notwendige Duengung kann durch Separation von Guelle in Fest- und Duennfraktion effektiver und kostenguenstiger durchgefuehrt werden. Der Naehrstoffgehalt des Guellefeststoffs sollte durch thermische Aufbereitung aufkonzentriert werden, so dass eine Vermarktung auch mit laengeren Transpoertwegen darstellbar ist. Die bei der thermischen Behandlung gewonnene Waerme kann prozessintern genutzt und ueberschuessige Waerme an Abnehmer in der naeheren Umgebung geliefert werden. Genauso besteht die Moeglichkeit, ein Brenngas zu erzeugen und die Energie mit Kraft-Waerme-Kopplung zu nutzen. (orig)

  8. [Anja Wilhelmi. Lebensweltlen von Frauen der deutschen Oberschicht im Baltikum (1800-1939). Eine Untersuchung anhand von Autobiographien] / Alexander Ewig

    Index Scriptorium Estoniae

    Ewig, Alexander, 1980-

    2011-01-01

    Arvustus: Wilhelmi, Anja. Lebenswelten von Frauen der deutschen Oberschicht im Baltikum (1800-1939). Eine Untersuchung anhand von Autobiographien. (Veröffentlichungen des Nordost-Instituts, 10.) (Wiesbaden : HArrassowitz 2008)

  9. Wachstum und Aufbau von Spongomorpha aeruginosa (Chlorophyta, Acrosiphoniales)

    NARCIS (Netherlands)

    Kornmann, Peter

    1967-01-01

    In zahlreichen Arbeiten dienten Algen als Objekte für das Studium von Regenerationsvorgängen und Erscheinungen der Polarität. Dagegen ist — von Chara abgesehen — über das normale Wachstum, den zeitlichen Ablauf von Teilung und Streckung der Zellen und die Entstehungsgeschichte des typischen Thallus

  10. Modellierung von Dienstleistungen mittels Business Service Blueprinting Modeling

    OpenAIRE

    Meis, Jochen; Menschner, Philipp; Leimeister, Jan Marco

    2010-01-01

    Der Beitrag stellt mit Business Service Blueprint Modeling (BSBM) einen konzeptionellen Ansatz zur Modellierung von Dienstleistungen vor, der ein systematisches und standardisiertes Vorgehen zur Modellierung von Dienstleistungen mit Kundeninteraktion anstrebt. BSBM verwendet hierzu die Business Process Modeling Notation (BPMN) in einem Service Blueprint (SB). Somit wird ein Modellierungskonzept geschaffen, das sowohl Kundeninteraktionspunkte berücksichtigt als auch von aktuellen Werkzeugen un...

  11. Spectral theory and quotients in Von Neumann algebras | West ...

    African Journals Online (AJOL)

    In this note we consider to what extent the functional calculus and the spectral theory in von Neumann algebras are preserved by the taking of quotients relative to two-sided ideals of the von Neumann algebra. Keywords:von Neumann algebra, functional calculus, spectral theory, quotient algebras. Quaestiones ...

  12. Market Timing und Finanzierungsentscheidungen: Unterscheidet sich Europa von den USA?

    NARCIS (Netherlands)

    Sautner, Z.; Spranger, J..

    2009-01-01

    Seit der Arbeit von Baker/Wurgler (2002) hat sich die Market-Timing-Theorie als alternative Kapitalstrukturtheorie etabliert. Sie impliziert, dass die Kapitalstruktur von Unternehmen das kumulierte Ergebnis von Versuchen des Equity Market Timing ist. Im Rahmen dieser Studie wird untersucht,

  13. Bewertung von Fahrzeuggeräuschen

    Science.gov (United States)

    Genuit, Klaus; Schulte-Fortkamp, Brigitte; Fiebig, André; Haverkamp, Michael

    Bei der Wahrnehmung und Beurteilung eines Automobils sind unzählige Merkmale und Eigenschaften von Bedeutung. Dabei können Merkmale objektiv-technisch beschrieben werden, wie Angaben zur Motorisierung, Höchstgeschwindigkeit, Drehmoment, zulässige Zuladung, Verbrauch usw. Daneben sind weitere Eigenschaften von Bedeutung, die sich einer einfachen objektiv-technischen Beschreibung entziehen. Hier sind Begriffe zu nennen, wie Sicherheit, allgemeine Qualitätsanmutung, Design, Ergonomie, Komfort, Haptik, Fahrdynamik, Zuverlässigkeit, die deutlich schwieriger objektiv erfassbar und beschreibbar sind (Abb. 4.1).

  14. [Von Recklinghausen disease and hepatic neurofibromatosis].

    Science.gov (United States)

    Guzman Toro, F; Hinestroza, D; Colmenares, D

    1995-01-01

    Von Recklinghausen's neurofibromatosis is one of the most common autosomal dominant disease with an estimated frecuency of 1:3000 live births. Characteristic lesions include cafe-au-lait spots and neurofibromas following the path of peripheral nerves. Liver involvement by neurofibromatosis is rare and very few cases have been reported. We present a case of a young man with Von Recklinhausen's disease and hepatic neurofibromatosis with multiple caf-au-lait spots, cutaneous neurofibromas, short stature and osseous lesions and compare the clinical, radiological, surgical and anatomopathological findings with others describe previously in the literature.

  15. Zur Aktivierung des Verbundtragverhaltens von Glaslaminaten

    OpenAIRE

    Sastré-Terrasa, Johannes (Hanno)

    2007-01-01

    Für jedes konstruktiv planerische Handeln ist ein fundiertes Wissen über die Baustoffe primäre Voraussetzung. Das trifft für Glas, auf Grund der Komplexität des Materialverhaltens, im besonderen Maße zu. Diese Arbeit beschäftigt sich deshalb zunächst mit dem Werkstoff Glas, den Grundlagen zum schadensfreien Fügen von Glas sowie dem Verhalten seiner Fügepartner. Die wichtigste Methode, das Kleben von Glas, wird im Wesentlichen durch die viskoelastischen und temperaturabhängig...

  16. Visualisation and interpretation of the autumn 2006 mise-a-la-masse survey data at the Olkiluoto site

    Energy Technology Data Exchange (ETDEWEB)

    Lehtonen, T. (Astrock Oy, Sodankylae (Finland))

    2007-07-01

    This report concerns mise-a-la-masse surveys conducted autumn 2006 at the area of the underground characterisation facility (ONKALO) and surroundings. Field surveys were made in both drillholes and on the ground surface. Suomen Malmi Oy conducted the fieldwork. Astrock Oy supervised field surveys and processed, interpreted and reported acquired data for Astrock Oy. The purpose of the study was to collect data for geological modelling with following continuity of the conducting features in bedrock from drillhole to drillhole and to ground surface. These conducting features in bedrock are often linked with lithologic characters or weakness zones. The completed survey supplements previous mise-a-la-masse measurement and on the other hand widens investigations to the newest drillholes OL-KR40-OL-KR43. A basis for the current survey was the previous mise-a-la-masse measurements and their results. Current earthings were placed in 15 electrically conducting structures in three drillholes, two at an investigation trench and one in ONKALO. Current earthings were situated in drillholes OL-KR4, OL-KR27 and OL-KR33, at OL-TK13 and at chainage 899 in ONKALO. Electrical connections were probed in nine drillholes, in four pregrouting holes and at two ground survey area. The acquired survey data were collected to xyz-coordinate oriented databases for 3D processing, interpreting and visualization of the results. At first the data were transferred to Oasis Montaj, where the potential field profiles were drawn and studied drillhole-by-drillhole current earthing at a time to determine characteristics of the electrical connections. Next probable connections between drillholes were constructed and moved to Surpac (registered trademark) Vision 3D software for visualisation. They were delivered for Posiva Oy as Surpac (registered trademark) string and DTM files. With the mise-a-la-masse data, it was possible to determine low dipping electrically conducting structures, congruent with the

  17. Erwachsenenbildung im Spannungsfeld von Wissenschaft, Politik und Praxis: Heide von Felden, Christiane Hof und Sabine Schmidt-Lauff (Hrsg.). [Rezension

    OpenAIRE

    Filla, Wilhelm

    2016-01-01

    Rezension von: Felden, Heide von/Hof, Christiane/Schmidt-Lauff, Sabine (Hrsg.) (2013): Erwachsenenbildung im Spannungsfeld von Wissenschaft, Politik und Praxis. Dokumentation der Jahrestagung der Sektion Erwachsenenbildung der Deutschen Gesellschaft für Erziehungswissenschaften vom 27. bis 29. September 2012. Baltmannsweiler: Schneider Verlag Hohengehren.

  18. Die Verteilung und Eigenschaften von Bodenformen in der Deutschen Bucht, eine Rekonstruktion der Karten von Ulrich (1973)

    DEFF Research Database (Denmark)

    Winter, Christian; Lefebvre, Alice; Benninghoff, Markus

    2015-01-01

    Entstehung, Gestalt und Dynamik von Bodenformen in vergleichsweise kleinen Untersuchungsgebieten ist die Arbeit von ULRICH (1973) über die Verteilung von Bodenformen in der Deutschen Bucht bis heute die einzige verfügbare zusammenhängende Darstellung für die deutsche Nordseeküste. Die analogen Karten und die...

  19. Der Briefwechsel zwischen Alexander von Humboldt und Karl Ernst von Baer

    Directory of Open Access Journals (Sweden)

    Thomas Schmuck

    2012-10-01

    Full Text Available Zusammenfassung Der kurze, nicht vollständig erhaltene Briefwechsel zwischen Alexander von Humboldt und Karl Ernst von Baer behandelt sehr verschiedene Themen: Politik, Kriegsgefahr, den Wissenschaftsbetrieb, Auszeichnungen und Tagungen, Embryologie und Cholera. Gemeinsam mit Briefen und Reden ergibt sich dabei ein differenziertes Bild der Beurteilung der beiden Wissenschaftler durch den jeweils anderen. Während Baer sich als Bewunderer Humboldts erweist, erscheint umgekehrt Humboldts Einschätzung Baers als ambivalent. Abstract The short, not completely preserved correspondence between Alexander von Humboldt and Karl Ernst von Baer deals with a wide range of subjects: politics and the danger of war, academic activities, scientific awards and conferences, aspects of embryology and the cholera. Letters to third persons and speeches, together with the correspondence between Humboldt and Baer show a differentiated pattern of mutual appraisal: While Baer always remained an admirer of the elder naturalist, Humboldt’s estimation was characterized by ambivalence.

  20. Interpenetration bei Parsons und Luhmann : Von der Integration zur Produktion von Unordnung

    OpenAIRE

    Künzler, Jan

    2010-01-01

    Talcott Parsons hatte den Interpenetrationsbegriff eingeführt, um strukturelle Beziehungen zwischen verschiedenen System arten erfassen zu können. Niklas Luhmann übernimmt den Begriff von Parsons und benutzt ihn nach weitreichenden Revisionen v. a. dazu, das Verhältnis von psychischen und sozialen Systemen auf den Begriff zu bringen. In dieser Intersystembeziehung spielt Sprache eine entscheidende Rolle. Ein systemtheoretisches Sprachkonzept, das dieser Vermittlungsleistung Rechnung trägt, st...

  1. Dentinhaftung von Zementen. Der Haftverbund von Zementen mit Dentin in Kombination mit verschiedenen indirekten Restaurationsmaterialien

    OpenAIRE

    Peutzfeldt, Anne; Sahafi, Alireza; Flury, Simon

    2011-01-01

    Einleitung: Die Anzahl zahnärztlicher Zemente sowie Restaurationsmaterialien steigt stetig. Die richtige Zementwahl für einen zuverlässigen Haftverbund zwischen Restaurationsmaterial und Zahnsubstanz ist von Interesse für den Kliniker. Ziel der vorliegenden in vitro-Studie war es daher, den Dentinhaftverbund von verschiedenen Zementen in Kombination mit verschiedenen indirekten Restaurationsmaterialien zu untersuchen. Material und Methoden: Zylindrische Probekörper aus sechs Restaurations...

  2. Identifizierung von Mikrodomän-Proteinen und funktionelle Charakterisierung von Cholesterin im Golgi-Apparat

    OpenAIRE

    Stüven, Ernstpeter

    2002-01-01

    Mittels Detergenzextraktion von Golgimembranen bei 0°C mit anschließender Dichtegradientenzentrifugation wurden sphingolipid- und cholesterinreiche Mikrodomänen isoliert, die zehn Proteine entsprechend der Coomassiefärbung in der SDS-PAGE enthalten. Im Rahmen dieser Arbeit wurden die zwei bisher nicht charakterisierten Proteine mit Molekulargewichten von 72 und 56 kDa als Untereinheiten A und B der vakuolären ATPase identifiziert. Daneben konnte mit NAP-22 eine elfte Komponente identifiziert ...

  3. Der "Bindungsfragebogen" von Grau und der "Bielefelder Fragebogen zu Partnerschaftserwartungen" von Hoger und Buschkamper im Vergleich

    National Research Council Canada - National Science Library

    Ina Grau; Ulrich Clashausen; Diether Hoger

    2003-01-01

    ...". Das Bindungsmuster ergibt sich aus der speziellen anhand von Clusteranalysen ermittelten Konfiguration der Skalen. In Clusteranalysen mit dem BinFB wurden vier Cluster aufgefunden, mit dem BFPE funf Cluster. Wahrend vier der BFPE-Cluster recht gut mit den vier BinFB-Clustern ubereinstimmen, wird eine funfte Personengruppe vom BFPE als "vermeidend-offnungsbereit" und von BinFB als "sicher" klassifiziert. Beide Interprctationsmoglichkeiten werden unter besonderer Berucksichtigung der Skala "Zuwendungsbedurfn...

  4. Authentizität von Milch und Fisch – Erkennung von Bioprodukten im Labor

    OpenAIRE

    Molkentin, Joachim

    2008-01-01

    Die Nachfrage nach Bio-Lebensmitteln ist in Deutschland in den letzten Jahren stetig gestiegen. So erhöhte sich der Absatz von Bio-Trinkmilch in 2007 im Vergleich zum Vorjahr erneut um 34 %. Aufgrund sporadisch resultierender Lieferengpässe bei Bio-Milch aber auch der erheblichen Handelspreisdifferenz – wie z. B. insbesondere bei Bio-Lachs – besteht ein potenzielles Risiko der Falschdeklaration konventioneller Produkte als Bio-Ware. Zum Schutz von Verbrauchern wie auch Erzeugern werden dah...

  5. Die Rezeptionsgeschichte von Ulrich Schmidels Wahrhaftige Beschreibung von 1567 bis heute

    OpenAIRE

    Obermeier, Franz

    2001-01-01

    Schmidels Werk hat bisher nur in Ansätzen die ihm zustehende Würdigung als eines der wichtigsten Quellenwerke der frühen Kolonialzeit Südamerikas erfahren. Es stand lange Zeit im Schatten des bekannteren und auch literarisch ansprechenderen Reisebuchs von Hans Staden (Wahrhaftige Historia, Marburg 1557), dessen persönliche Schilderung seiner Gefangenschaft dem modernen Leser durch den geschickten Einsatz von narrativen Elementen entsprechend der heutigen Genretradition des persönlich gefasste...

  6. Analyse von Arbeitsplätzen auf halbautomatischen Pflanzmaschinen mit Hilfe von MTM (Methods Time Measurement)

    OpenAIRE

    Remmele, Edgar

    2017-01-01

    Mit Hilfe von MTM (Methods Time Measurement), einem System vorbestimmter Zeiten, werden Bewegungsstudien an drei verschiedenen halbautomatischen Pflanzmaschinen durchgeführt. Hauptunterscheidungsmerkmal der untersuchten Pflanzmaschinen ist die Methode der Übergabe der Pflanze von der Pflanzperson an die Pflanzmaschine. Analysiert wird der Arbeitsplatz der Pflanzmaschine ACCORD-Standard mit der Methode Klemmscheibe, PES-Beetpflanzer 1500/1900 mit der Methode Pflanzfinger und Lännen RT-2 mit de...

  7. Zur Entwicklung von Containerschiffsflotten : eine Paneldatenanalyse

    OpenAIRE

    Prinz, Alexander; Schulze, Peter M.

    2004-01-01

    Diese Arbeit untersucht die regional aggregierten Containerschiffsflotten der wichtigsten Wirtschaftsräume entlang der Hauptverkehrsrouten der Seeschifffahrt. Anhand einer Paneldatenanalyse mit festen Effekten werden die positive Abhängigkeit der Containerschifffahrt von Weltwirtschaft und Welthandel quantifiziert und erklärende Variablen für die Entwicklung der Containerschifffahrt identifiziert.

  8. Von Kalifornien nach Taxham / Katri Soe

    Index Scriptorium Estoniae

    Soe, Katri, 1971-

    2005-01-01

    Neljas osa magistritööst "Von Kalifornien nach Taxham: Formen und Strukturen der Kommunikation in Peter Handkes Romanen "Der kurze Brief zum langen Abschied" und "In einer dunklen Nacht ging ich aus meinem stillen Haus"" (Tartu, 2000. Juhendaja: Claus Sommerhage)

  9. Euler-Chelpin, Prof. Hans von

    Indian Academy of Sciences (India)

    Euler-Chelpin, Prof. Hans von. Nobel Laureate (Chemistry) - 1929. Date of birth: 15 February 1873. Date of death: 6 November 1964 ... Posted on 21 December 2017. ASTROPHYSICS: An Observational View of the Universe. Math Art and Design: MAD about Math, Math Education and Outreach. Math and Finance ...

  10. Ueberreste vorweltlicher Proboscidier von Java und Banka

    NARCIS (Netherlands)

    Martin, K.

    1884-01-01

    Junghuhn führte in seinem Werke über Java nur einen einzigen Wirbelthierrest, Carcharias megalodon, an (7, IV, pag. 97); es war ihm nicht gelungen bei seinem ersten Aufenthalte auf der Insel Reste von Säugethieren zu finden, so eifrig er auch darnach in den Höhlen des Tertiaergebirges suchte (7, IV,

  11. Alte und neue Scyphomedusen von Australien

    NARCIS (Netherlands)

    Stiasny, G.

    1926-01-01

    In einer Collection Coelenterata, von verschiedenen australischen Fundorten herrührend, die mir vom Direktor des Australian Museum in Sydney, Dr. Ch. Anderson, zur Untersuchung übersendet wurden, fanden sich auch einige Scyphomedusen, die in den australischen Gewässern bisher noch nicht nachgewiesen

  12. Eigenschaften von Gott. Eine quantitative Analyse

    Directory of Open Access Journals (Sweden)

    Thomas Benesch

    2016-12-01

    Full Text Available ENGLISH: A quantitative research on 32 pupils of an elementary school (third and fourth class was performed. The questions regarded to socio-demographic issues as well as so called opposition pairs for God. These opposition pairs include the semantic differential of the loving God combined with the selection of 27 opposition pairs which were derived from literature. The image of God has been developed due to a factor analysis with respect to human and divine properties. These characteristics are depending on the religious education of children as well as their habits of reading in the Holy Bible. DEUTSCH: Eine quantitative Erhebung von 32 Volksschulkindern einer 3. und 4. Klasse wurde einerseits mit erweiterten sozio-demographischen Fragen und gleichzeitig mit Gegensatzpaaren für Gott beschrieben. Die Gegensatzpaare beinhalteten das semantische Differential des liebenden Gottes zusammen mit einer Auswahl von 27 Gegensatzpaaren, die deduktiv aus der Literatur abgeleitet wurden. Das Gottesbild hat sich anhand einer Faktorenanalyse darin entwickelt, dass Gott einerseits mit menschlichen Attributen versehen wird und andererseits mit Eigenschaften von Gott. Diese Eigenschaften von Gott sind abhängig davon, ob die Kinder religiös erzogen werden und ob sie gerne die Heilige Schrift lesen.

  13. Molecular mechanisms of von Willebrand Factor mechanoregulation

    NARCIS (Netherlands)

    Jakobi, A.J.|info:eu-repo/dai/nl/311489621

    2012-01-01

    Von Willebrand factor (VWF) multimers mediate primary adhesion and aggregation of platelets. The potency to recruit platelets critically depends on the size of VWF multimers, which is regulated by a feedback mechanism involving shear-induced unfolding of the A2 domain in VWF and cleavage by the

  14. Measurements and von Neumann projection/collapse

    Indian Academy of Sciences (India)

    unwanted superpositions of (system + apparatus)-states can be shown to be suppressed, leading eventually to the projection/collapse rule postulated in von Neumann's treatment of measurements [3]. In the next section, the measurement problem in quantum mechanics (QM) is recalled. In §3, some proposed improvements ...

  15. Guido von Pirquet: Austrian pioneer of astronautics

    Science.gov (United States)

    Sykora, F.

    1977-01-01

    The works of Guido von Pirquet, Austrian pioneer of rocketry, were assessed. Major emphasis was given to Pirquet's calculation of the route to Venus which in fact was followed by the first Russian rocket to Venus. Of interest also is Pirquet's valuable construction of a space station and his analysis of interstellar space flight.

  16. Soolopartiid Von Krahli katuse all / Kristi Eberhart

    Index Scriptorium Estoniae

    Eberhart, Kristi

    2007-01-01

    Von Krahli Teatri kolmest lavastusest: "Erki ja Tiina" (lavastaja Mart Kangro, tantsivad Erki Laur ja Tiina Tauraite), "Faust" (J. W. Goethe ainetel tekst ja lavastus Taavi Eelmaa, muusika ja laulud Chalice, osades Jarek Kasar ja Rein Pakk), "Hamletid" (William Shakespeare'i ainetel kontseptsiooni, lavastuse, koreograafia, kujunduse, valguse autor Sasha Pepeljajev, video- ja helikunstnik Taavet Jansen. Esitaja Juhan Ulfsak)

  17. De ziekte van Von Hippel-Lindau

    NARCIS (Netherlands)

    Los, M.; Links, T.P.; Lenders, J.W.M.; Voest, E.E.

    2000-01-01

    Von Hippel-Lindau disease (VHL) is an autosomal dominant inherited cancer syndrome. The disease was diagnosed in three patients: a 22-year-old woman who presented with decreased vision due to retinal angiomatosis and in whom a renal carcinoma was diagnosed five years later at a routine VHL analysis,

  18. Ueber eine Anomalie von Acromitus flagellatus (Stiasny)

    NARCIS (Netherlands)

    Stiasny, G.

    1934-01-01

    Bei erneuter Durchsicht des reichhaltigen Materiales von Acromitus flagellatus (Stiasny) in der Scyphomedusen-Sammlung des Rijksmuseum van Natuurlijke Historie in Leiden (vergl. meine Mitteilungen daruber, 1920, Uebersichtstabelle III und 1921, p. 131/136) fand ich ein Exemplar, das eine

  19. Laue, Prof. Max Theodor Felix von

    Indian Academy of Sciences (India)

    Home; Fellowship. Fellow Profile. Elected: 1954 Honorary. Laue, Prof. Max Theodor Felix von. Nobel Laureate (Physics) - 1914. Date of birth: 9 October 1897. Date of death: 24 April 1960. YouTube; Twitter; Facebook; Blog. Academy News. IAS Logo. Theory Of Evolution. Posted on 23 January 2018. Joint Statement by the ...

  20. Ueber zwei neue Vogelarten von Java

    NARCIS (Netherlands)

    Finsch, O.

    1902-01-01

    Die beiden nachstehend beschriebenen Vögel wurden mir von Herrn Max Bartels als muthmasslich neu zugesandt. Die genaue Untersuchung hat dies bestätigt. Ich freue mich daher eine der Arten zu Ehren des Entdeckers benennen zu können. Seit einigen Jahren als Leiter der Plantage Pangerango bei Pasir

  1. Classical diagnostic radiological features of Von Recklinghausen's ...

    African Journals Online (AJOL)

    Neurofibromatosis type 1(NF-1, Von Recklinghausen disease or peripheral NF) is a rare autosomal dominant disorder with varied clinical manifestations involving the skin, nerves and bones. It is the most common of the neurocutaneous syndromes, with variable pathological and clinical expression. Approximately half of all ...

  2. Joint bleeding in von Willebrand disease

    NARCIS (Netherlands)

    Galen, K.P.M. van

    2017-01-01

    Von Willebrand disease (VWD) is the most common inherited bleeding disorder occurring in approximately 1/100 people. Until now, joint bleeds did not get much attention in clinical research on VWD, since mucocutaneous bleeding is predominant. However, recurrent joint bleeds lead to arthropathy, the

  3. Das Druckprofil von Sportkompressionsstrümpfen.

    Science.gov (United States)

    Reich-Schupke, Stefanie; Surhoff, Stefan; Stücker, Markus

    2016-05-01

    Zunehmend werden Sportkompressionsstrümpfe (SKS) eingesetzt, doch fehlt eine Norm in Analogie zu medizinischen Kompressionsstrümpfen (MKS). Ziel dieser Pilotstudie war der Vergleich der Druckprofile von fünf SKS ex vivo und in vivo miteinander sowie mit MKS-Normen. CEP Running-Progressive-Socks, Falke Running--Energizing, Sigvaris Performance, X-Socks Speed-Metal-Energizer und 2XU Compression--Race-Socks wurden an zehn Leistungssportlern (standardisiert in vivo, Kikuhime--Sensor) sowie im Hohenstein Institut (ex vivo) hinsichtlich ihres Druckprofils getestet. Die Ex-vivo-Messungen im Fesselbereich von CEP (25,6 mmHg) und 2XU (23,2 mmHg) entsprachen der deutschen MKS-Klasse 2, von Sigvaris-SKS (20,8 mmHg) der deutschen MKS-Klasse 1. Die übrigen SKS lagen darunter. Die ermittelten Druckprofile differierten stark und entsprachen nicht der MKS-Norm. Die In-vivo-Messungen zeigten für drei SKS (2XU, CEP, Sigvaris) durchschnittlich einen höheren Anpressdruck als die SKS von Falke und X-Socks. Alle SKS lagen in vivo jedoch unter der deutschen MKS-Klasse 1. Kein SKS bot den für MKS geforderten Druckabfall vom Messpunkt B nach D. Die in vivo und ex vivo ermittelten SKS-Druckprofile zeigten heterogene Ergebnisse und folgten kaum den MKS-Anforderungen. Entsprechend sind auch die klinisch-praktischen Effekte von SKS nicht vergleichbar. Wünschenswert wäre eine SKS-Klassifikation, die erlaubt, Produkte einzuordnen, zu vergleichen und nach konkreten Vorlieben und Bedürfnissen (hoher vs. geringer Druck, progressiver vs. degressiver Gradient) auszuwählen. © 2016 Deutsche Dermatologische Gesellschaft (DDG). Published by John Wiley & Sons Ltd.

  4. Structural Design and Sealing Performance Analysis of Biomimetic Sealing Ring.

    Science.gov (United States)

    Han, Chuanjun; Zhang, Han; Zhang, Jie

    2015-01-01

    In order to reduce the failure probability of rubber sealing rings in reciprocating dynamic seal, a new structure of sealing ring based on bionics was designed. The biomimetic ring has three concave ridges and convex bulges on each side which are very similar to earthworms. Bulges were circularly designed and sealing performances of the biomimetic ring in both static seal and dynamic seal were simulated by FEM. In addition, effects of precompression, medium pressure, speed, friction coefficient, and material parameters on sealing performances were discussed. The results show that von Mises stress of the biomimetic sealing ring distributed symmetrically in no-pressure static sealing. The maximum von Mises stress appears on the second bulge of the inner side. High contact stress concentrates on left bulges. Von Mises stress distribution becomes uneven under medium pressure. Both von Mises stress and contact stress increase when precompression, medium pressure, and rubber hardness increase in static sealing. Biomimetic ring can avoid rolling and distortion in reciprocating dynamic seal, and its working life is much longer than O-ring and rectangular ring. The maximum von Mises stress and contact stress increase with the precompression, medium pressure, rubber hardness, and friction coefficient in reciprocating dynamic seal.

  5. Structural Design and Sealing Performance Analysis of Biomimetic Sealing Ring

    Directory of Open Access Journals (Sweden)

    Chuanjun Han

    2015-01-01

    Full Text Available In order to reduce the failure probability of rubber sealing rings in reciprocating dynamic seal, a new structure of sealing ring based on bionics was designed. The biomimetic ring has three concave ridges and convex bulges on each side which are very similar to earthworms. Bulges were circularly designed and sealing performances of the biomimetic ring in both static seal and dynamic seal were simulated by FEM. In addition, effects of precompression, medium pressure, speed, friction coefficient, and material parameters on sealing performances were discussed. The results show that von Mises stress of the biomimetic sealing ring distributed symmetrically in no-pressure static sealing. The maximum von Mises stress appears on the second bulge of the inner side. High contact stress concentrates on left bulges. Von Mises stress distribution becomes uneven under medium pressure. Both von Mises stress and contact stress increase when precompression, medium pressure, and rubber hardness increase in static sealing. Biomimetic ring can avoid rolling and distortion in reciprocating dynamic seal, and its working life is much longer than O-ring and rectangular ring. The maximum von Mises stress and contact stress increase with the precompression, medium pressure, rubber hardness, and friction coefficient in reciprocating dynamic seal.

  6. Influence of stationary and non-stationary conditions on drying time and mechanical properties of a porcelain slab

    Science.gov (United States)

    Hammouda, Imen; Mihoubi, Daoued

    2017-12-01

    This work deals with a numerical study of the response of a porcelain slab when subjected to convective drying in stationary and non-stationary conditions. The used model describes heat, mass, and momentum transfers is applied to an unsaturated viscoelastic medium described by a Maxwell model. The numerical code allows us to determine the effect of the surrounding air temperature on drying kinetics and on mechanical stress intensities. Von Mises stresses are analysed in order to foresee an eventual damage that may occur during drying. Simulation results for several temperatures in the range of [30 °C, 90 °C] shows that for the temperature from 30 °C to 60 °C, Von Mises stresses are always lower than the yield strength. But above 70 °C, Von Mises stresses are higher than the ultimate strength, and consequently there is a risk of crack at the end of the constant drying rate period. The idea proposed in this work is to integrate a reducing temperature phase when the predicted Von Mises stress intensity exceeds the admissible stress. Simulation results shows that a non-stationary convective drying (90-60 °C) allows us to optimize costs and quality by reducing the drying time and maintaining Von Mises stress values under the admissible stress.

  7. Structural Design and Sealing Performance Analysis of Biomimetic Sealing Ring

    Science.gov (United States)

    Han, Chuanjun

    2015-01-01

    In order to reduce the failure probability of rubber sealing rings in reciprocating dynamic seal, a new structure of sealing ring based on bionics was designed. The biomimetic ring has three concave ridges and convex bulges on each side which are very similar to earthworms. Bulges were circularly designed and sealing performances of the biomimetic ring in both static seal and dynamic seal were simulated by FEM. In addition, effects of precompression, medium pressure, speed, friction coefficient, and material parameters on sealing performances were discussed. The results show that von Mises stress of the biomimetic sealing ring distributed symmetrically in no-pressure static sealing. The maximum von Mises stress appears on the second bulge of the inner side. High contact stress concentrates on left bulges. Von Mises stress distribution becomes uneven under medium pressure. Both von Mises stress and contact stress increase when precompression, medium pressure, and rubber hardness increase in static sealing. Biomimetic ring can avoid rolling and distortion in reciprocating dynamic seal, and its working life is much longer than O-ring and rectangular ring. The maximum von Mises stress and contact stress increase with the precompression, medium pressure, rubber hardness, and friction coefficient in reciprocating dynamic seal. PMID:27019582

  8. The effect of type of restoration on the stress field developed in terminal abutments with severely reduced periodontal support and coronal structure.

    Science.gov (United States)

    Stasinopoulou, Ioanna; Manda, Marianthi; Galanis, Christos; Koidis, Petros

    2013-10-01

    Periodontally compromised teeth (PCT) that serve as terminal abutments (TAs) are often challenging depending on the post-and-core treatment, the type of partial fixed dental prosthesis (PFDP), and the periodontal support. The purpose of this study was to investigate the biomechanical impact of 3 types of PFDP supported by cast post-and-cores on PCT serving as terminal abutments. A 3-dimensional (3D) model of a human mandible was fabricated by using computed tomography (CT) images and parameterized in a computer-aided design (CAD) environment as follows: Right premolar preparation geometries were designed. The second premolar was assembled with 7-mm or 10-mm cast post-and-core models. Both premolar-models were designed to support single, splinted, or 1-unit cantilever splinted crowns. In each situation, their periodontium geometries were designed to be reduced by 10%, 50%, and 70%. All models were imported into a 3D finite element analysis (FEA) environment and loaded; von Mises stress values and distribution patterns were evaluated. Insertion of the post primarily affected the apical areas of both the root and post; the type of PFDP and periodontal support mainly affected stress distribution. In patients with a normal periodontium, splinting the teeth did not contribute to their stress relief. By extending the post length, a stressful area close to the apex of the post was developed. Splinting mitigated the stress field of the coronal part of the 50% PCT (up to 98.9%); the 30% PCT experienced a substantial decrease (up to 215.9%) in stress in the radical part as well. The increase in the length of the post produced negligible stress-related differences in the apical part of the 50% PCT (0.2% to 2.6%). The use of the 7-mm post effectively relieved the radical part of the splinted 30% PCT. The magnitude of the stress on the radical part of post-restored PCT was considerably increased in the presence of a cantilever. Splinted crowns supported by a 7-mm cast post

  9. Influence of S, P, C on grain boundary diffusion and creep properties of Alloy 800; Einfluss von S, P, C auf die Korngrenzendiffusion und Kriecheigenschaften von Alloy 800

    Energy Technology Data Exchange (ETDEWEB)

    Lindemann, J.; Hannesen, K.; Mast, R.; Viefhaus, H. [Max-Planck-Institut fuer Eisenforschung GmbH, Duesseldorf (Germany); Grabke, H.J.

    1998-12-31

    The paper reports examinations of Alloy 800 and specific commercially available variants known under the names of 800H, 800HT, and 800LC, differing in their concentrations of C, Al, and Ti. In addition, melts also containing phosphorus (0.09 wt-%) or sulfur (0.04 wt-%) as additional alloying materials have been prepared for the experiments. The volume diffusion and the grain boundary diffusion of {sup 59}Fe in those alloys was measured at temperatures between 800 and 1000 C by means of a radioactive tracer method combined with residual activity measurements. It was found that accompanying elements like phosphorus and sulfur increase the activation energy of the grain boundary diffusion of the iron and thus delay the grain boundary self-diffusion in Alloy 800. Creep curves were measured of the same materials after age-hardening treatment for 100 hours at 800 C, measurements performed at constant temperature but at three different, constant creep stress loads. The results showed that addition of phosphorus markedly increases the lifetime of Alloy 800, and reduces the creep rupture strain. The minimum strain rate in Alloy 800 containing 0.09 wt-% of phosphorus was found to be lower by a factor of 100, as compared to the other Alloy 800 materials used. (orig./CB) [Deutsch] Alloy 800 ist ein austenitischer Fe-Ni-Cr Stahl, der relativ geringe, aber wichtige Konzentrationen von Kohlenstoff, Aluminium und Titan enthaelt. Besondere Varianten von Alloy 800, bekannt als 800H, 800HT und 800LC, unterscheiden sich in den Konzentrationen dieser Elemente. Diese kommerziellen Legierungen wurden untersucht, und zusaetzlich wurden Schmelzen mit zulegiertem Phosphor (0,09 Gew-%) bzw. Schwefel (0,04 Gew-%) hergestellt. Mittels einer radioaktiven Tracermethode in Verbindung mit Restaktivitaetsmessungen wurde die Volumen- und Korngrenzendiffusion von {sup 59}Fe in diesen Legierungen im Temperaturbereich 800-1000 C gemessen. Es wurde gefunden, dass Begleitelemente wie Phosphor und

  10. The Stigma of Stress and The Absence of Agency

    DEFF Research Database (Denmark)

    Mølholm, Martin; Vetner, Mikael

    2018-01-01

    on stress in Danish journals on leadership and management and in newspapers over a decade has contributed to creating an intricate stress stigma and an absence of agency. Seit mehr als 15 Jahren setzt Stress die Agenda in die dänischen Work-Life-Diskurse. Täglich fehlen 35.000 Beschäftigte aufgrund von...

  11. Visualization and interpretation of the year 2004 mise-a-la- masse survey data at Olkiluoto site

    Energy Technology Data Exchange (ETDEWEB)

    Lehtonen, T. [Astrock Oy, Sodankylae (Finland)

    2006-01-15

    This report concerns mise-a-la-masse surveys conducted from late autumn 2004 to early winter 2005 at the area of the underground characterisation facility (Onkalo) and surroundings. Surveys were made in 21 boreholes and at 6 ground survey areas. Suomen Malmi Oy conducted the fieldwork. Astrock Oy supervised field surveys and processed, interpreted and reported acquired data for Posiva Oy. The purpose of the study was to collect data for geological modelling with following continuity of the conducting features in bedrock from borehole to borehole and to ground surface. These conducting features in bedrock are often linked with lithologic characters or weakness zones. A basis for the current survey was the previous mine-a-la-masse measurements and their results. Current earthings were placed in 26 electrically conducting structures in 8 boreholes and in one outcrop. Current earthings were situated in boreholes KR4, KR7, KR8, KR25, KR27, KR28, KR29 and KR33. Electrical connections were probed in 22 boreholes and at 6 ground survey areas. The acquired survey data were collected to xyz-coordinate oriented databases for 3D processing, interpreting and visualization of the results. At first the data were transferred to Oasis Montaj, where the potential field profiles were drawn and studied borehole-by-borehole current earthing at a time to determine characteristics of the electrical connections. Next were constructed probable connections between boreholes and moved to SurpacVision for visualisation. They were delivered for Posiva Oy as Surpac string and DTM files. With the mise-a-la-masse data, it was possible to determine numerous low dipping electrically conducting structures. Ground surveys were hampered strongly by electrical disturbances of the infrastructure of the Olkiluoto. Results of the all surveys are also collected in the same table, where every one of connections is classified. Interpretations are merely based on mise-a-la-masse data. (orig.)

  12. Visualization and interpretation of the year 2005 mise-a-la-masse survey data at Olkiluoto site

    Energy Technology Data Exchange (ETDEWEB)

    Lehtonen, T. (Astrock Oy, Sodankylae (Finland))

    2006-06-15

    This report concerns mise-a-la-masse surveys conducted autumn 2005 at the area of the underground characterisation facility (Onkalo) and surroundings. Surveys were made in 14 boreholes and at 1 ground survey area. Suomen Malmi Oy conducted the fieldwork. Astrock Oy supervised field surveys and processed, interpreted and reported acquired data for Posiva Oy. The purpose of the study was to collect data for geological modelling with following continuity of the conducting features in bedrock from borehole to borehole and to ground surface. These conducting features in bedrock are often linked with lithologic characters or weakness zones. A basis for the current survey was the previous mine-a-la-masse measurements and their results. Current earthings were placed in 15 electrically conducting structures in 8 boreholes and in one outcrop. Current earthings were situated in boreholes KR4, KR7, KR25, KR27 and KR37. Electrical connections were probed in 14 boreholes and at 1 ground survey area. The acquired survey data were collected to xyz-coordinate oriented databases for 3D processing, interpreting and visualization of the results. At first the data were transferred to Oasis Montaj, where the potential field profiles were drawn and studied borehole-by-borehole current earthing at a time to determine characteristics of the electrical connections. Next probable connections between boreholes and moved were constructed and moved to SurpacVision for visualisation. They were delivered for Posiva Oy as Surpac string and DTM files. With the mise-a-la-masse data, it was possible to determine numerous low dipping electrically conducting structures. Additionally previously detected conducting structures were updated with the observations and interpretations. Ground surveys were hampered strongly by electrical disturbances of the infrastructure of the Olkiluoto. Results of the all surveys are also collected in the same table, where every one of connections is classified

  13. Characterization of a dismissed landfill via electrical resistivity tomography and mise-à-la-masse method

    Science.gov (United States)

    De Carlo, Lorenzo; Perri, Maria Teresa; Caputo, Maria Clementina; Deiana, Rita; Vurro, Michele; Cassiani, Giorgio

    2013-11-01

    Electrical resistivity methods are widely used for environmental applications, and they are particularly useful for the characterization and monitoring of sites where the presence of contamination requires a thorough understanding of the location and movement of water, that can act as a carrier of solutes. One such application is landfill studies, where the strong electrical contrasts between waste, leachate and surrounding formations make electrical methods a nearly ideal tool for investigation. In spite of the advantages, however, electrical investigation of landfills poses also challenges, both logistical and interpretational. This paper presents the results of a study conducted on a dismissed landfill, close to the city of Corigliano d'Otranto, in the Apulia region (Southern Italy). The landfill is located in an abandoned quarry, that was subsequently re-utilized about thirty years ago as a site for urban waste disposal. The waste was thought to be more than 20 m thick, and the landfill bottom was expected to be confined with an HDPE (high-density poli-ethylene) liner. During the digging operations performed to build a nearby new landfill, leachate was found, triggering an in-depth investigation including also non-invasive methods. The principal goal was to verify whether the leachate is indeed confined, and to what extent, by the HDPE liner. We performed both surface electrical resistivity tomography (ERT) and mise-à-la-masse (MALM) surveys, facing the severe challenges posed by the rugged terrain of the abandoned quarry complex. A conductive body, probably associated with leachate, was found as deep as 40 m below the current landfill surface i.e. at a depth much larger than the expected 20 m thickness of waste. Given the logistical difficulties that limit the geometry of acquisition, we utilized synthetic forward modeling in order to confirm/dismiss interpretational hypotheses emerging from the ERT and MALM results. This integration between measurements and

  14. Integrales Lernen in und von Organisationen

    Directory of Open Access Journals (Sweden)

    Wendelin Kupers

    2006-06-01

    Full Text Available Bezogen auf das integrale Models von Ken Wilber untersucht der Beitrag die Bedeutung des Lernens in und von Organisationen. Nach einer Darstellung der Relevanz und des Grundverständnisses des Lernens im Organisationskontext, werden integrale Dimensionen des Lernens dargestellt. Im Einzelnen werden die verschiedenen Sphären eines inneren-subjektiven und äusseren-„objektiven“ Lernens des Einzelnen als auch ein gemeinschaftliches Lernen und Lernen im System auf der kollektiven Ebene dargestellt sowie deren interrelationaler Zusammenhang diskutiert. Schließlich beschreibt der Beitrag noch integrale Lernprozesse sowie integrale Gestaltungsfelder zur Förderung des Lernens in den verschiedenen Bereichen. Abschließend spricht der Artikel noch Schwierigkeiten und Probleme an sowie nimmt im Fazit ein perspektivischen Ausblick vor.

  15. Laboratory Testing for Von Willebrand Factor Multimers.

    Science.gov (United States)

    Oliver, Susan; Lau, Kun Kan Edwin; Chapman, Kent; Favaloro, Emmanuel J

    2017-01-01

    Von Willebrand disease (VWD) is reportedly the most common inherited bleeding disorder and can also arise as an acquired syndrome (AVWS). These disorders develop due to defects and/or deficiency of the plasma protein von Willebrand factor (VWF). Laboratory testing for the VWF-related disorders requires assessment of both VWF level and VWF activity, the latter requiring multiple assays because of the many functions carried out by VWF to help prevent bleeding. As an additional step, an evaluation of VWF structural features by multimer analysis is useful in selective investigations. The current paper therefore describes a protocol for assessment of VWF multimers by gel electrophoresis, thus enabling identification of protein bands that represent differently sized multimers. The sample protocol described in this chapter is the methodology developed by Sebia.

  16. Wir zeigen andere Bilder von Frauen ...

    Directory of Open Access Journals (Sweden)

    Bettina Rulofs

    2010-03-01

    Full Text Available Der vorliegende Beitrag beleuchtet die Bedeutung der Geschlechterordnung im Prozess der sportmedialen Kommunikation. Im Kern geht es um die Frage, inwiefern im Prozess der medialen Vermittlung von Sport traditionelle Geschlechterstereotype aufrechterhalten werden oder Möglichkeiten der Irritation solcher Stereotype bestehen. Dazu werden verschiedene Ebenen des massenmedialen Kommunikationsprozesses in den Blick genommen: die Medienprodukte, die Öffentlichkeitsarbeit und Selbst-Präsentation der Sportler/innen, die Medienrezeption und die Herstellungsprozesse von Medien in den Sportredaktionen. This article illustrates the relevance of gender in processes of sports media communication. The question in focus is in what way traditional gender stereotypes are perpetuated in the process of media communication in sport and how such stereotypes can be irritated. Therefore different levels of mass media communication are considered: the media products, the public relations of athletes and the presentation of themselves as athletes, the media-reception and the production processes in sport departments of media institutions.

  17. Virchow's triad: Kussmaul, Quincke and von Recklinghausen.

    Science.gov (United States)

    Stanifer, John W

    2016-02-01

    For most of the 19th century, Germany was the centre of the medical world. From there the most innovating research came and many of the physicians of that era are known to nearly every medical student and physician of today. Virchow, Kussmaul, Quincke, von Recklinghausen, Müller and Schönlein are familiar names in today's medicine but insofar as they are merely eponyms associated with signs, symptoms, disease and anatomy. The story of their lives, their research and their influence on each other has been little examined. This is an essay about Virchow's relationship with his mentors Müller and Schönlein and how these relationships shaped the development of Kussmaul, Quincke and von Recklinghausen as students of Virchow and their work in medicine and clinical observation after leaving Virchow's laboratory. © The Author(s) 2014.

  18. Evolution equations of von Karman type

    CERN Document Server

    Cherrier, Pascal

    2015-01-01

    In these notes we consider two kinds of nonlinear evolution problems of von Karman type on Euclidean spaces of arbitrary even dimension. Each of these problems consists of a system that results from the coupling of two highly nonlinear partial differential equations, one hyperbolic or parabolic and the other elliptic. These systems take their name from a formal analogy with the von Karman equations in the theory of elasticity in two dimensional space. We establish local (respectively global) results for strong (resp., weak) solutions of these problems and corresponding well-posedness results in the Hadamard sense. Results are found by obtaining regularity estimates on solutions which are limits of a suitable Galerkin approximation scheme. The book is intended as a pedagogical introduction to a number of meaningful application of classical methods in nonlinear Partial Differential Equations of Evolution. The material is self-contained and most proofs are given in full detail. The interested reader will gain a ...

  19. Stress distribution in delayed replanted teeth splinted with different orthodontic wires: a three-dimensional finite element analysis.

    Science.gov (United States)

    de Souza, Fernando Isquierdo; Poi, Wilson Roberto; da Silva, Vanessa Ferreira; Martini, Ana Paula; Melo, Regis Alexandre da Cunha; Panzarini, Sonia Regina; Rocha, Eduardo Passos

    2015-06-01

    The aim was to evaluate the biomechanical behavior of the supporting bony structures of replanted teeth and the periodontal ligament (PDL) of adjacent teeth when orthodontic wires with different mechanical properties are applied, with three-dimensional finite element analysis. Based on tomographic and microtomographic data, a three-dimensional model of the anterior maxilla with the corresponding teeth (tooth 13-tooth 23) was generated to simulate avulsion and replantation of the tooth 21. The teeth were splinted with orthodontic wire (Ø 0.8 mm) and composite resin. The elastic modulus of the three orthodontic wires used, that is, steel wire (FA), titanium-molybdenum wire (FTM), and nitinol wire (FN) were 200 GPa, 84 GPa, and 52 GPa, respectively. An oblique load (100 N) was applied at an angle of 45° on the incisal edge of the replanted tooth and was analyzed using Ansys Workbench software. The maximum (σmax) and minimum (σmin) principal stresses generated in the PDL, cortical and alveolar bones, and the modified von Mises (σvM) values for the orthodontic wires were obtained. With regard to the cortical bone and PDL, the highest σmin and σmax values for FTM, FN, and FA were checked. With regard to the alveolar bone, σmax and σmin values were highest for FA, followed by FTM and FN. The σvM values of the orthodontic wires followed the order of rigidity of the alloys, that is, FA > FTM > FN. The biomechanical behavior of the analyzed structures with regard to all the three patterns of flexibility was similar. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  20. La Medea de Lars von Trier

    Directory of Open Access Journals (Sweden)

    Iratxe Fresneda Delgado

    2013-04-01

    Full Text Available El presente artículo analiza el modo en el que Lars von Trier recrea para el cine el estereotipo de Medea. Mediante el análisis fílmico de la película y apoyándose en los estudios culturales, el texto se interroga acerca de la importancia y el poder potencial del cine a la hora recuperar el antiguo mito y demostrar su vigencia. El análisis amplía horizontes para la compresión de los mecanismos que articulan el entramado de significados de la película, donde Von Trier aporta una nueva visión del arquetipo de Medea uniéndola, a la tradición pictórica del Romanticismo. Una influencia que habita en las posteriores obras del director danés, donde el paisaje, la naturaleza, se erige en elemento catalizador de las pulsiones humanas, en su cómplice y testigo.This paper explores the way that Lars von Trier’s film recreates the stereotype of Medea. Using film analysis and based on cultural studies the article asks about the importance and potential power of cinema to recover the ancient myth and show their effects. The analysis expands horizons for the understanding of the mechanisms that link the network of meanings of the film, where the author offers a new vision of Medea's archetype attaching it to the pictorial tradition tied to the Romanticism. An influence that can be seen in the later works of Lars von Trier, where the landscape, the nature, stands as a catalyst of human drives, as his accomplice and witness.

  1. Von Medien, Übertragungen und Automaten

    Directory of Open Access Journals (Sweden)

    Alessandro Barberi

    2013-12-01

    Full Text Available Im Zuge der Debatten zum Medialen Habitus wurde vielfach betont, dass die >Theorie der Praxispraxeologischen Medientheorie< des Medialen Habitus avant la lettre gesprochen werden kann. Dieser Artikel untersucht – ausgehend von den Debatten zur "Medienkompetenz" – wie Bourdieu Sprache, Sprechen und Diskurs, sowie Akteure, Felder und Habitus als Medien begreift und betont dabei die Nützlichkeit der Bourdieuschen Bildungssoziologie im Rahmen einer sozialwissenschaftlichen Grundlegung der Medienpädagogik.

  2. Untersuchungen von Nanostrukturen magnetischer Kolloide mit Kleinwinkelstreuung

    OpenAIRE

    Kammel, Martin

    2005-01-01

    Mit Hilfe der Neutronenkleinwinkelstreuung mit polarisieren Neutronen wird eine Analyse so genannter Ferrofluide durchgeführt. Ferrofluide sind Dispersionen magnetisierbarer Teilchen, welche durch in den meisten Fällen organische Hüllen gegen irreversibler Aggregation geschützt sind. Anhand von verdünnten Magnetit-Kolloidlösungen wurden als Stabilisierung Dextran, Tenside (Laurinsäure/Marlipal) und elektrostatisch stabilisierte Magnetitteilchen untersucht. Dabei fanden sich in jedem dieser Fl...

  3. Maschinelle Erkennung von Verkehrsteilnehmern mittels heterogener Sensorik

    OpenAIRE

    Walchshäusl, Leonhard

    2009-01-01

    In modernen Fahrzeugen halten verstärkt Fahrerassistenzsysteme zum Insassenschutz und zum Schutz anderer Verkehrsteilnehmer Einzug. Typische, bereits seit längerem verfügbare Systeme, wie Airbag und Antiblockiersystem, erreichen schon heute eine hohe Marktdurchdringung. Künftige aktive Sicherheitssysteme, die von der Kollisionswarnung bis hin zur autonomen Gefahrenbremsung reichen, sind Gegenstand aktueller Forschung. Insbesondere Systeme, die aktiv in das Fahrgeschehen eingreifen, erfordern ...

  4. Mikrobieller Befall von Elektrotauchlack in der Automobilindustrie

    OpenAIRE

    Gühring, Ina Katrin

    2000-01-01

    Nach Umstellung auf umweltverträglichere Lackmaterialien (Reduzierung biozid wirkender Lösemittel, Schwermetalle) traten in Elektrotauchanlagen verschieder Werke der DaimlerChrysler AG vermehrt Beschichtungsstörungen bei Karossen auf. Dabei war ein pH-Anstieg des Lackmaterials, Schichtdickenanstieg, Abblättern des Lacks („Striptease“ Effekt), Oberflächenstörungen (Pusteln, Blasen, Krater), schlechter Umgriff, eine Bildung von Lackschlamm und geringerer Schichtwiderstand zu beobachten. Gleichz...

  5. Die Usability von Rich Internet Applications

    Science.gov (United States)

    Linder, Jörg

    Interaktiven Services, die dem Themenkreis Web 2.0 zugeordnet werden, haftet unter anderem das Attribut an, besonders leicht bedienbar zu sein. Flickr, Youtube und Wikipedia gelten als Erfolgsprojekte dieser neuen Art von interaktiven Websites. Wodurch zeichnet sich nun eine Usability 2.0 (so es sie überhaupt geben sollte) aus? Was ist zu beachten, wenn so genannte Rich Internet Applications gestaltet werden?

  6. Therapie von Vorhofflimmern: Rolle der Katheterablation

    OpenAIRE

    Hindricks G; Kircher S; Gaspar T.; Arya A

    2009-01-01

    Vorhofflimmern ist die häufigste Herzrhythmusstörung in der Gesamtbevölkerung und geht einher mit erhöhter Morbidität und Mortalität. Als prinzipielle Behandlungskonzepte stehen die "Frequenzkontrolle" und die "Rhythmuskontrolle" zur Verfügung. Während sich die medikamentöse Rhythmuskontrolle als insgesamt unzureichend erwiesen hat, stellt die Katheterablation von Vorhofflimmern einen etablierten, potenziell kurativen Therapieansatz mit beachtlichen Erfolgsraten dar. Obwohl hinsichtlich d...

  7. Modellierung von Preiserwartungen durch neuronale Netze

    OpenAIRE

    Heinemann, Maik; Lange, Carsten

    1997-01-01

    Das Papier untersucht, wie Erwartungsbildung mit Hilfe neuronaler Netze modelliert werden kann. Die Grundlage bildet ein Cobweb-Modell, in dem Firmen Preiserwartungen auf Basis eines Feedforward-Netzes bilden.Zunächst wird anhand von Simulationen gezeigt, daß Firmen durch neuronale Erwartungsbildung approximativ rationale Erwartungen bilden können. Im Gegensatz zur Hypothese rationaler Erwartungen ist dafür die Kenntnis des relevanten Modells nicht mehr erforderlich, lediglich Beobachtungen d...

  8. Expression von Blutgruppenantigenen durch humane mesenchymale Stammzellen

    OpenAIRE

    Schüle, Michael Christian

    2013-01-01

    Die vorliegende experimentelle Arbeit befasst sich mit der Untersuchung der Expression von Blutgruppenantigenen durch humane mesenchymale Stammzellen (MSC) aus dem Knochenmark. Der Fokus lag hierbei auf den klinisch bedeutsamen Antigenen A, B, H, Rhesus-D, -C, -c, -E, -e, RhAG, K, k, Jka, Jkb und DARC. Die Expression wurde systematisch auf Genom-, Transkriptom- und Proteinebene evaluiert. Alle untersuchten MSC Populationen exprimierten FUT1, RHCE, KEL und Kidd (HUT11) mRNA. mRNA der AB0-Gl...

  9. Weitere Vorkommen von Impatiens capensis in Hessen

    OpenAIRE

    Nawrath, Stefan

    1996-01-01

    Neue hessische Fundorte von Impatiens capensis aus dem Taunus und dessen Vorland sowie aus der Rheinebene werden berichtet. Die insbesondere im Schwarzbach-System zahlreichen Fundorte werden beschrieben und in einer Verbreitungskarte dargestellt. New Hessian stations of Impatiens capensis in the Taunus mountains as well as their foothills and in the Rhine valley are reported on. The stations which are particularly numerous in the Schwarzbach system, are described and demonstrated on a dist...

  10. Nondestructive characterization of materials damage; Zerstoerungsfreie Charakterisierung von Werkstoffschaedigung

    Energy Technology Data Exchange (ETDEWEB)

    Dobmann, G. [Fraunhofer Inst. fuer Zerstoerungsfreie Pruefverfahren, IZFP, Saarbruecken (Germany)

    1999-08-01

    The paper discusses two examples of application of NDT for early detection of materials damage, or ageing effects. The first case shows the potential of micromagnetic testing techniques for early detection of hydrogen-induced stress corrosion cracking in pipework. Pipe specimens made of steel X20Cr13, which differed in materials state induced by various heat treatments, were exposed to corrosive attack induced in a closed cycle by simultaneous rinsing with NACE solution and stress application through stamp impact. Various micromagnetic testing parameters were measured at the specimens` outside surface during the annealing period. Further, fatigue experiments were made with specimen sets made of steel 1.4541, under various mechanical and temperature stresses (room temperature and 300 C), for measuring the remanent magnetization of the cylindrical fatigue test blocks (equal geometry) cut out of the specimens, in order to conclude information on the martensite content and the fatigue effects. (Orig./CB) [Deutsch] In diesem Beitrag werden zwei Beispiele der ZFP zur Frueherkennung von Werkstoffschaedigung und Alterungserscheinungen diskutiert. Zum einen wurde das Potential mikromagnetischer Pruefverfahren zur Frueherkennung wasserstoffinduzierter, auch kathodische Spannungsrisskorrosion genannt (HISCC, hydrogene induced stress corrosion cracking), an Rohrleitungen nachgewiesen. Rohrproben unterschiedlicher Waermebehandlungszustaende der Stahlguete X20Cr13 wurden durch gleichzeitiges Spuelen mit NACE-Loesung in einem geschlossenen Kreislauf und Beaufschlagen einer Spannung durch Stempeldruck dem Korrosionsangriff ausgesetzt. Waehrend der Auslagerung wurden verschiedene mikromagnetische Pruefgroessen an der Aussenseite der Rohrproben aufgenommen. Zum anderen wurden an Probensaetzen der Stahlqualitaet 1.4541 Ermuedungsexperimente bei unterschiedlichen mechanischen und Temperaturbelastungen (bei Raumtemperatur und 300 C) durchgefuehrt. Das Ziel war die Messung der

  11. [Orthopaedic manifestations of Von Recklinghausen's neurofibromatosis].

    Science.gov (United States)

    Trigui, Moez; Ayadi, Kamel; Sakka, Mourad; Zribi, Wassim; Frikha, Faten; Gdoura, Fakher; Sallemi, Sami; Zribi, Mohamed; Keskes, Hassib

    2011-03-01

    Von Recklinghausen's neurofibromatosis is a dominant autosomic genetic disease characterized by different clinical manifestations. The goal of this work was to study its orthopaedic manifestations and to show the characteristics of their management. A retrospective study was carried out on 15 patients having a Von Recklinghausen's neurofibromatosis. For each patient, different orthopaedic manifestations and their evolution after treatment were analyzed. These manifestations were classified in spinal deformities, pseudarthrosis of long bones and tumours of the peripheral nerves. The spinal deformities were observed in 9 cases. A dystrophic scoliosis was observed in 6 patients with an average angle of 50° and was associated to a kyphosis in 5 patients. The treatment was surgical by posterior arthrodesis in 2 cases and circumferential arthrodesis in 2 cases. The congenital curves and pseudarthroses of leg were observed in 5 cases, localized at the lower third of the leg in all cases. An Ilizarov external fixator with segmental osseous transport was carried out in 2 patients. The duration of the external fixator was 23 months ½ with 5 interventions in each case. Four plexiform neurofibromas and 3 nodular neurofibromas were observed. A transformation into neurofibrosarcoma was found in 2 patients. In one case, a resection without functional sacrifice was carried out and in the other case the patient was dead before the resection. The orthopaedic manifestations of Von Recklinghausen's neurofibromatosis are frequent, varied and have a difficult management. The functional and sometimes vital prognoses are challenging. Copyright © 2010 Elsevier Masson SAS. All rights reserved.

  12. Treatment of patients with von Willebrand disease

    Directory of Open Access Journals (Sweden)

    Tuohy E

    2011-04-01

    Full Text Available Emma Tuohy1, Emma Litt1, Raza Alikhan1,21Department of Haematology, University Hospital of Wales, Cardiff, UK; 2Haemophilia and Thrombosis Centre, University Hospital of Wales, Cardiff, UKAbstract: Von Willebrand disease (vWD is the most common hereditary bleeding disorder. The aim of therapy is to correct the dual hemostatic defect, due to defective platelet adhesion-aggregation and abnormal coagulation due to Factor VIII (FVIII deficiency. The choice of treatment depends on a number of factors, including the severity of the bleed, the procedure planned, the subtype and severity of the disease and the age and morbidity of the patient. Desmopressin (DDAVP is the treatment of choice for type 1 vWD as it increases endogenous release of FVIII and von Willebrand factor (vWF and is also used in some subtypes of type 2 vWD. In those patients in whom DDAVP is ineffective or contraindicated, levels can be restored by infusing vWF:FVIII concentrates. The role of antifibrinolytic treatment is an important adjunct to replacement therapy during minor or major surgery involving mucosal surfaces. The dosing and timing of vWF:FVIII concentrates is important depending on the nature of the surgical procedure. The role of secondary prophylaxis needs to be further defined.Keywords: von Willebrand disease, treatment, DDAVP 

  13. Doping dependence of the elastic behaviour of silicon; Dotierungsabhaengikeit des elastischen Verhaltens von Silizium

    Energy Technology Data Exchange (ETDEWEB)

    Santen, Nicole

    2010-02-24

    stress is observed in the local environment of the probes. TEM images confirm that this stress relaxation is to led back on dislocation rings, which have been formed during the annealing of the implantation damages by agglomeration of intrinsic defects. Therefore the formation of dislocations in the strained channel region of n-MOSFETs would have fatal consequences, because these lead to unwanted decreasement of the stresses, which consequently would diminish the power of integrated circuits. [German] Fuer eine kontinuierliche Steigerung der Leistungsfaehigkeit von Halbleiterbauelementen und integrierten Schaltungen spielt neben der fortschreitenden Miniaturisierung auch gedehntes Silizium (strained silicon) eine wichtige Rolle. Durch Einbringen einer mechanischen Verspannung in den Kanalbereich eines MOSFETs ist es moeglich, die Ladungstraegerbeweglichkeit und somit die Schaltgeschwindigkeiten von Transistoren zu erhoehen. Um eine fehlerfreie Funktion der Bauteile zu gewaehrleisten, sind systematische Untersuchungen dieser Verspannungen im Elementhalbleiter Silizium und ihre Wechselwirkung mit Defekten, zu denen auch Dotierungsatome gehoeren, notwendig. Die Methode der gestoerten {gamma}-{gamma}-Winkelkorrelation (PAC) ist sehr gut fuer die Untersuchung lokaler Spannungsfelder in duennen Schichten von Halbleitern geeignet, da sie Informationen ueber die direkte Gitterumgebung eines Sondenkernes auf atomarer Skala liefert. Auf diese Art koennen lokale Gitterverzerrungen in Silizium untersucht werden, die einerseits in implantierten Schichten auftreten und andererseits durch extern angelegte Zug- und Druckspannungen entstehen. In der vorliegenden Arbeit wurde der Einfluss einer Dotierung auf das elastische Verhalten von Silizium untersucht. Neben der PAC-Sonde {sup 111}In wurden diverse Fremdatome mittels Ionenimplantation in den Siliziumkristall eingebracht. Anschliessend wurden die dabei entstandenen Strahlenschaeden durch eine thermische Behandlung ausgeheilt. Zur

  14. Gestalt und Funktion von Animal Design : Versuch einer semiotischen Analyse

    OpenAIRE

    Schlüter, Wolfgang

    2009-01-01

    Dissertation zur Gestalt und Funktion von Animal Design (tieranaloges Design). Untersucht wird eine Auswahl an Produkten, die in ihrem Äußeren an Tiere erinnern. Hierbei stehen Aspekte wie die Emotionalisierung von Produkten, demonstrativer Konsum und die soziale Funktion im Fokus der Analyse. Anhand von Abbildungen und Zeichnungen wird u.a. dargestellt, welche Bedeutung die Tiergestalt für das jeweilige Produktdesign hat. Die Objekte werden jeweils unter phänomenologischen, hermeneutischen u...

  15. Bioethik in der Ukraine: Von Medizinischer zur Integrativen Bioethik

    OpenAIRE

    Gubenko, Anna

    2014-01-01

    Im Artikel wird die Chronologie der Entstehung und Entwicklung der Bioethik in der Ukraine analysiert. Dabei werden drei Hauptetappen der Herausbildung von Bioethik als a) einer gesellschaftlichen Organisation, b) einer Lerndisziplin und c) einer integrativen Wissenschaft unterschieden. Der Autor hat den Vektor von medizinischer zur integrativen Bioethik durch Ausbildung und soziale sowie pädagogische Praktiken bezeichnet. In diesem Sinne wird der Begriff von “pädagogischer Bioethik“ einge...

  16. Portrait of Dr. Von Braun with Walt Disney, 1954.

    Science.gov (United States)

    1954-01-01

    Marshall Center Director Dr. Wernher Von Braun is pictured with Walt Disney during a visit to the Marshall Space Flight Center in 1954. In the 1950s, Dr. Von Braun while working in California on the Saturn project, also worked with Disney studios as a technical director in making three films about Space Exploration for television. Disney's tour of Marshall in 1965 was Von Braun's hope for a renewed public interest in the future of the Space Program at NASA.

  17. Risiko und Akzeptanz von Industrieansiedlungen: Eine empirische Studie

    OpenAIRE

    Burgemeister, Jörg; Weber, Martin

    1992-01-01

    In der Bundesrepublik Deutschland stoßen Industrieansiedlungen oft auf den Widerstand der Bevölkerung. Bei der Akzeptanz einer Ansiedlung sind von den Bürgern subjektiv wahrgenommene Risiken und Nutzen der Ansiedlung von erheblicher Bedeutung. In einer Fragebogenstudie haben wir untersucht, wie Personen die Nutzen und Risiken von Industrieansiedlungen einschätzen, inwieweit sie Absiedlungen akzeptieren, welche Bestimmungsfaktoren ihren Risiko- und Akzeptanzurteilen zugrundeliegen, und wie sic...

  18. Erfolgsfaktoren von Internet-Auktionen: Eine empirische Analyse in PLS

    OpenAIRE

    Fritz, Wolfgang; Möllenberg, Antje; Dees, Heiko

    2004-01-01

    Internet-Auktionen haben sich zu einem der erfolgreichsten Geschäftsmodelle im E-Commerce entwickelt. Die stetig steigende Anzahl von Auktionen beim Marktführer eBay zeugen von einer zunehmenden Beliebtheit solcher Auktionen. Doch welche Determinanten beeinflussen den Erfolg einer Internet-Auktion? Im vorliegenden Beitrag wird dieses Thema aus dem Blickwinkel des Verkäufers am Beispiel von Ticket-Auktionen empirisch untersucht. Im Mittelpunkt steht dabei eine Kausalanalyse, die den Einfluss v...

  19. Saage tuttavaks : Elisabeth ja Karl von Hoerschelmann / Mai Levin

    Index Scriptorium Estoniae

    Levin, Mai, 1942-

    2004-01-01

    Kuraator M. Levin kuni 10. X 2004 Adamson-Ericu muuseumis avatud näitusest "Tuntud ja tundmatud Elisabeth von Rosendorff-Hoerschelmann ja Karl von Hoerschelmann". Enamik töid on kunstnike laste Konstantin Hoerschelmanni ja Anna Röder-Hoerschelmanni omand. Elisabeth Rosendorff (1898-1984) sündis Virumaal Maidlas eesti perekonnas, Karl von Hoerschelmann (1899-1951) Sevastoopolis saksa perekonnas

  20. Abbaukinetiken - und mechanismen von Lignin und Vanillin unter hydrothermalen Bedingungen

    OpenAIRE

    Curtze, Jan Henning

    2017-01-01

    Eine Methode zur energetischen Aufkonzentrierung von feuchten Abfallbiomassen ist die Hydrothermale Carbonisierung (HTC). Um technische HTC-Reaktoren rational auslegen zu können, sollte die Formalkinetik der vier Hauptkomponenten von Biomasse - Kohlenhydrate, Lignin, Fette/Öle und Proteine – bekannt sein. Des Weiteren spielt die Änderungskinetik des Feststoffes während der HTC eine wichtige Rolle. Der Fokus dieser Arbeit liegt auf der Untersuchung der HTC von Lignin, was ein hochkomplexes, ch...

  1. Studien zur Kinetik der Fehlfaltung un Aggregation von Proteinen

    OpenAIRE

    Modler, Andreas Johannes

    2003-01-01

    Diese Arbeit befasst sich mit der Kinetik der Fehlfaltung und Aggregation von Proteinen. Anhand dreier Beispiele, der Phosphoglyceratkinase (PGK) aus Hefe, einer Variante von Barstar und des Prion-Proteins des Syrischen Hamsters (SHaPrP(90-232)) wurde insbesondere die Kinetik der Bildung von Amyloidfibrillen und deren kinetischer Vorläuferstrukturen mittels dynamischer und statischer Lichtstreuung, Circulardichroismus, Infrarotspektroskopie, Elektronenmikroskopie und teilweise analytischer Ch...

  2. Exécution des marchés publics mise en oeuvre administrative et financière

    CERN Document Server

    Serr, Fabien

    2013-01-01

    L'exécution des marchés publics constitue la phase critique de mise en oeuvre de tous les éléments préparés lors de la passation du marché ; c'est aussi la période de gestion administrative, financière et technique des événements prévus ou non sur un chantier. Cet ouvrage opérationnel et juridique détaille la mise en oeuvre du marché et décrypte, au travers de 27 chapitres, chaque phase de l'exécution administrative et financière de tout type de marché : suivi, sous-traitance, garantie, paiement, décompte, réception, recours amiables, etc. Exécution des marchés publics permet de : - disposer d'une vue d'ensemble de l'exécution des marchés publics ; - s'approprier le cadre juridique de l'exécution (Code des marchés publics, textes réglementaires ou législatifs, CCAG et règles de la comptabilité publique, etc.) ; - maîtriser les différentes phases de l'exécution et leur articulation ; - respecter l'ensemble des étapes, les points de procédures à suivre, etc. De nombreux tabl...

  3. Dr. von Braun and Army Ballistics Missile Agency (ABMA) Group

    Science.gov (United States)

    1959-01-01

    This photograph of Dr. von Braun, shown here to the left of General Bruce Medaris, was taken in the fall of 1959, immediately prior to Medaris' retirement from the Army. At the time, von Braun and his associates worked for the Army Ballistics Missile Agency in Huntsville, Alabama. Those in the photograph have been identified as Ernst Stuhlinger, Frederick von Saurma, Fritz Mueller, Hermarn Weidner, E.W. Neubert (partially hidden), W.A. Mrazek, Karl Heimburg, Arthur Rudolph, Otto Hoberg, von Braun, Oswald Lange, Medaris, Helmut Hoelzer, Hans Maus, E.D. Geissler, Hans Heuter, and George Constan.

  4. Einfluss von rekombinantem Adiponektin auf die monozytäre Expression von Annexin A6

    OpenAIRE

    Stögbauer, Fabian

    2009-01-01

    In der vorliegenden Arbeit wurden zunächst die CD14 Micro Beads titriert und so die Menge an CD14 Micro Beads bestimmt, die nötig ist, um eine große Anzahl Monozyten mit einem hohen Reinheitsgrad, verbunden mit geringen Kosten, aus Vollblut isolieren zu können. In den folgenden in vitro Untersuchungen wurden dann periphere Monozyten von humanen Spendern isoliert, um die dosis- und zeitabhängige Veränderung der Annexin A6-Proteinexpression unter dem Einfluss von Adiponektin feststellen zu k...

  5. Einfluss von Eugenol und Silikonöl auf die Dentinhaftung von adhäsiven Befestigungsmaterialien

    OpenAIRE

    Bigdali, Puria

    2015-01-01

    Zielsetzung Eugenolhaltige Zemente und Silikone stehen in Verdacht den Verbund von Kompositzementen zu beeinflussen. Ziel dieser Arbeit war es den Einfluss eugenolhaltiger und eugenolfreier Zemente und von Additions- und Kondensationssilikonen auf konventionell adhäsive und selbstadhäsive Kompositzemente zu untersuchen. Material und Methode Aus 200 extrahierten Rinderzähnen wurden 200 Dentinscheiben mit einer Dicke von 1 mm hergestellt, in welche eine definierte Kavität mit einem ...

  6. Automatisierte Generierung von Postleitzahlgebieten aus OpenStreetMap-Daten unter Verwendung von Open Source GIS Software

    OpenAIRE

    Hauck, Christian

    2011-01-01

    Das Projekt OpenStreetMap als freie Wiki-Weltkarte gewinnt als Quelle von Geodaten für unter-schiedlichste Bedürfnisse innerhalb der Geowissenschaften, des Geomarketings und auch im Alltag immer mehr an Bedeutung. Die kostenlosen, von Freiwilligen einer Community gesammelten geo-graphischen Daten, sogenannte nutzergenerierte Daten, dienen heute vielen Anwendern als Daten-grundlage und stehen in der Konkurrenz zu proprietären Geodaten von kommerziellen Anbietern. Neben Straßendaten sind zahlre...

  7. Mise en oeuvre et caracterisation de pieces autotrempantes elaborees avec de nouveaux alliages meres

    Science.gov (United States)

    Bouchemit, Arslane Abdelkader

    (≈ 4 %m) developpes par Ian Bailon-Poujol lors de sa maitrise [20]. La haute teneur en carbone de ces alliages meres assure la protection des elements d'alliage susceptibles a l'oxydation durant toutes les etapes du procede : dans le bain liquide lors de la fusion et l'atomisation a l'eau, pendant le broyage ainsi que lors du frittage des pieces contenant ces alliages meres. Precedemment, Ian Bailon-Poujol avait etudie le broyage de certains alliages meres atomises a l'eau et avait amorce le developpement de melanges autotrempants ainsi que des etudes de diffusion des elements d'alliage. Pour ce projet, le developpement des melanges autotrempants a implique l'optimisation de toutes les etapes de la mise en oeuvre afin d'obtenir les meilleures proprietes possibles des melanges avant frittage (ecoulement, resistance a cru...) et apres frittage (durete, microstructure...), et ce, pour des alliages meres atomises a l'eau par Ian Bailon-Poujol ainsi qu'un alliage mere de chimie similaire qui fut atomise au gaz. (Abstract shortened by ProQuest.).

  8. Laser beam joining of materials for the automotive industry; Laserstrahlfuegen von innovativen Werkstoffen fuer die Automobilindustrie

    Energy Technology Data Exchange (ETDEWEB)

    Alvensleben, F. von [Laser Zentrum Hannover e.V. (Germany); Haferkamp, H.; Kreutzburg, K.; Marquering, M.

    1995-12-31

    The specific advantages of laser beam joining technologies like welding and brazing are the local energy input, the low thermal stress of the components, the high degree of automation and the high quality of machining. In this paper, laser welding of zinc-coated steel, Tailored Blanks, and aluminum and magnesium diecasting alloys is presented. The influence of the laser, process and material parameters on the joining results are discussed. The laser welding seams are investigated by non-destructive, destructive and metallographical methods. Joined car body components may show wide gaps and joints due to the manufacturing tolerances of the sheet part production. Therefore, the laser beam brazing process can be used to join components with wide joining gaps, and investigations are being carried out concerning brazing of steel sheets using a laser beam. (orig.) [Deutsch] Die Fuegetechnologie Schweissen und Loeten mit Laserstrahlung zeichnen sich durch ihre definierte Energieeinbringung, geringe thermische Belastungen fuer das zu bearbeitende Bauteil sowie hohe Bearbeitungsqualitaeten und gute Automatisierungsmoeglichkeiten aus. In diesem Zusammenhang werden Ergebnisse zum Laserstrahlschweissen von massgeschneiderten Zuschnitten als Tailored Blanks, von verzinkten Stahlblechen sowie von Aluminium- und Magnesiumdruckguss praesentiert. Aufgrund der Fertigungstoleranzen koennen Fuegebereiche z.B. in der Karosseriefertigung oftmals grosse Fugen bzw. Spalte aufweisen. Hierfuer bietet das Laserstrahlloeten Moeglichkeiten, Bauteile mit grossen Fuegetoleranzen zu verbinden. Daher werden verfahrens- und werkstoffspezifische Erkenntnisse zum Loeten an Stahlwerkstoffen unter Zugabe entsprechender Loetwerkstoffe vorgestellt. (orig.)

  9. Ööklubi Club von Überlingen = Club von Überlingen

    Index Scriptorium Estoniae

    2008-01-01

    Ööklubi Club von Überlingen (Madara 22A, Tallinn) sisekujundusest. Sisearhitekt: Taavi Aunre (Boom.ee OÜ). Taavi Aunrest, tema tähtsamad tööd. I-II korruse plaan, 11 värv. vaadet, foto T. Aunrest

  10. Von den Liven von Oesel / August Ludwig Schlözer

    Index Scriptorium Estoniae

    Schlözer, August Ludwig

    2008-01-01

    Avaldatud Eberhard Winkleri initsiatiivil A. L. Schlözeri teose põhjal: Gesammelte Nachrichten von den Ueberresten der Liven, in Livland und Kurland. (1770), mis moodustab osa teosest: Schlözer, August Ludwig. M. Johann Joseph Haigold's Beylagen zum Neuveränderten Russland. Zweiter Theil. Riga und Leipzig, 1770

  11. Aino Lepik von Wiren / Aino Lepik von Wiren ; interv. Kadi Alatalu

    Index Scriptorium Estoniae

    Lepik von Wirén, Aino, 1961-

    2007-01-01

    Heinrich Marga eksiilvalitsuse (20.06.1990-7.10.1992) kohtuminister Aino Lepik von Wiren pagulaslapse elust Rootsis, haridusest ja elukutse valikust, tööst eksiilvalitsuses, tööleasumisest Eestisse 1992. aastal, seadusandlikust tegevusest ning aluse panekust välismaalaste- ja kodakondsuspoliitikale, naiste võimalustest poliitilisse tippu tõusmiseks, kodu- ja väliseestlaste vastandamisest

  12. Rezension: Träume von Räumen von Georges Perec

    Directory of Open Access Journals (Sweden)

    Thomas Ballhausen

    2015-12-01

    Full Text Available Mit "Träume von Räumen" liegt ein zentraler Text aus dem umfangreichen Œuvre Geroges Perecs vor, der zuletzt 1990 als Übersetzung greifbar war. Der ursprünglich 1974 erschienene Band ist in mehrfacher Hinsicht wesentlich für das Verständnis Perecs und seiner literarisch-philosophische Wunderwelt ...

  13. Mise au point d'un protocole de mesures d'émissions gazeuses et odorantes lors de la mise en oeuvre d'un enrobé bitumineux à chaud

    OpenAIRE

    Jullien, Agnès; Moneron, Pierre; GUIEYSSE, Bernard; LABORATOIRE CENTRAL DES PONTS ET CHAUSSEES - LCPC

    2002-01-01

    Cette convention de partenariat LCPC-SETRA-DDE41 s'inscrit en matière de routes et déchets associés, dans le cadre des dispositions législatives de juillet 1992, visant à limiter la mise en décharge dès juillet 2002 aux seuls déchets ultimes et ainsi même à favoriser les pratiques de recyclage. Le recyclage, si il doit être étendu dans les années futures, doit cependant faire l'objet d'études prévisionnelles, notamment environnementales, permettant d'optimiser le taux de recyclage dans chaque...

  14. Wege des Exports von Glutathion aus Astrocyten

    OpenAIRE

    Minich, Tobias Florian

    2008-01-01

    Vorliegender Arbeit lag die Aufgabe zugrunde herauszufinden, welche(s) Transportsystem(e) außer dem Multidrug-Transporter 1 (multidrug resistance protein 1, MRP1) zum Austritt des Tripeptides Glutathion aus Primärkulturen von Astrogliazellen in das extrazelluläre Milieu beitragen. Als Grundlage für die Untersuchungen wurde zunächst an zwei Wildtyp Mausstämmen (NMRI und FVB/N) sichergestellt, dass astrogliareiche Primärkulturen aus Mäusen sowohl reduziertes als auch oxidiertes Glutathion expor...

  15. Die Behandlung von Intersexuellen in der Diskussion

    Directory of Open Access Journals (Sweden)

    Heinz-Jürgen Voß

    2008-11-01

    Full Text Available Wissenschaftler/-innen aus unterschiedlichen Fachdisziplinen und mit unterschiedlichen Ansichten zum Umgang mit intersexuellen Menschen kommen zu Wort – in diesem Sinne ist der Sammelband sehr heterogen. Es werden Erfahrungen mit Geschlechtsanpassung dargestellt, Begrifflichkeiten analysiert und Probleme bei der Therapie und in der Forschung erörtert. Vorangestellt, aber erfreulicherweise nicht abgetrennt, äußern sich Betroffene. Bereits wegen der sich im Abschluss des Bandes befindlichen Handlungsempfehlungen zur Behandlung von Säuglingen und Kindern mit ‚abweichenden‘ bzw. ‚uneindeutigen‘ Geschlechtsmerkmalen, die sich insbesondere an Eltern, Mediziner/-innen und Sozialpädagog/-innen wenden, ist das Buch unbedingt empfehlenswert.

  16. Electronic Resource Management System. Vernetzung von Lizenzinformationen

    OpenAIRE

    Michaela Selbach; Daniel Armin Rupp

    2014-01-01

    In den letzten zehn Jahren spielen elektronische Ressourcen im Bereich der Erwerbung eine zunehmend wichtige Rolle: Eindeutig lässt sich hier ein Wandel in den Bibliotheken (fort) vom reinen Printbestand zu immer größeren E-Only-Beständen feststellen. Die stetig wachsende Menge an E-Ressourcen und deren Heterogenität stellt Bibliotheken vor die Herausforderung, die E-Ressourcen effizient zu verwalten. Nicht nur Bibliotheken, sondern auch verhandlungsführende Institutionen von Konsortial- und ...

  17. Authentifizierung von Bio-Milch im Labor

    OpenAIRE

    Molkentin, Joachim

    2008-01-01

    In Deutschland ist die Nachfrage nach Bio-Lebensmitteln in den letzten Jahren stetig gestiegen. So erhöhte sich der Absatz von Bio-Trinkmilch in 2007 im Vergleich zum Vorjahr erneut kräftig um 34 Prozent (ZMP, Bonn) und der Bio-Anteil beträgt inzwischen bei Frischmilch knapp elf Prozent. Aufgrund sporadisch resultierender Lieferengpässe bei Bio-Milch sowie der vorhandenen Handelspreisdifferenz besteht zunehmend ein potenzielles Risiko der Falschdeklaration konventionell erzeugter Milch als Bi...

  18. Der Denkmalwert von Illegalität

    OpenAIRE

    Beyer, Dennis

    2012-01-01

    Kunst oder Schmiererei - Graffiti spalten die Gesellschaft. Für die einen sind sie illegale Schmierereien und Ausdruck von Vandalismus, für die anderen gelten sie als Kunst am Bau einer verkannten Avantgarde. Das Spektrum an Motivationen und Produkten innerhalb der Sprayer-Gemeinschaft ist tatsächlich derart vielfältig, dass eine sachliche Debatte ohne Polarisation kaum möglich scheint. Dennoch stellt sich die Frage, welche Bedeutung diese flüchtigen und illegalen Zeugnisse einer Minderheit i...

  19. Comparison of automated von Willebrand factor activity assays

    DEFF Research Database (Denmark)

    Timm, Annette; Hillarp, Andreas; Philips, Malou

    2015-01-01

    INTRODUCTION: Von Willebrand Disease (VWD) is the most common inherited bleeding disorder. Measurement of von Willebrand factor (VWF) activity in plasma is often based on platelet agglutination stimulated by the ristocetin cofactor activity. Novel assays, based on latex beads with recombinant...

  20. Illustrierte Bestimmungshilfe zur Unterscheidung von Candelaria concolor und Candelaria pacifica

    OpenAIRE

    Stapper, Norbert J.

    2012-01-01

    Unterscheidungsmerkmale von Candelaria concolor und C. pacifica werden anhand von Makro- und Mikrofotos dargestellt. Im Gelände kann C. pacifica anhand der fehlenden Unterrinde erkannt werden. Characteristic features separating Candelaria concolor from C. pacifica are presented on macro and micro photographs. The lack of a lower cortex can be used to identify C. pacifica in the field.

  1. On two matrix derivatives by Kollo and von Rosen

    OpenAIRE

    Neudecker, Heinz

    2003-01-01

    The article establishes relationships between the matrix derivatives of Fwith respect to Xas introduced by von Rosen (1988), Kollo and von Rosen (2000) and the Magnus-Neudecker (1999) matrix derivative. The usual transformations apply and the Moore-Penrose inverse of the duplication matrix is used. Both Xand F have the same dimension. Peer Reviewed

  2. A New Generalization of von Neumann Relative Entropy

    Science.gov (United States)

    Li, Jing; Cao, Huaixin

    2017-11-01

    In quantum information, von Neumann relative entropy has a great applications and operational interpretations in diverse fields, and von Neumann entropy is an important tool for describing the uncertainty of a quantum state. In this paper, we generalize the classical von Neumann relative entropy S( ρ|| σ) and von Neumann entropy S( ρ) to f-von Neumann relative entropy \\widetilde {S}f(ρ ||σ ) and f-von Neumann entropy \\widetilde {S}f(ρ ) induced by a logarithm-like function f, respectively, and explore their properties. We prove that \\widetilde {S}f(ρ ||σ ) is nonnegative and then prove that \\widetilde {S}f(ρ ) has nonnegativity, boundedness, concavity, subadditivity and so on. Later, we show the stability and continuity of the \\widetilde {S}f(ρ ) with respect to the trace distance. In the case that f( x) = -log x, the resulted entropies reduce the classical von Neumann relative entropy and von Neumann entropy, respectively. This means that our results extend the usual results to a more general setting and then have some potential applications in quantum information.

  3. An accurate von Neumann's law for three-dimensional foams

    NARCIS (Netherlands)

    Hilgenfeldt, Sascha; Kraynik, Andrew M.; Koehler, Stephan A.; Stone, Howard A.

    2001-01-01

    The diffusive coarsening of 2D soap froths is governed by von Neumann's law. A statistical version of this law for dry 3D foams has long been conjectured. A new derivation, based on a theorem by Minkowski, yields an explicit analytical von Neumann's law in 3D which is in very good agreement with

  4. Minimum Moduli in Von Neumann Algebras | Gopalraj | Quaestiones ...

    African Journals Online (AJOL)

    Minimum Moduli in Von Neumann Algebras. Perumal Gopalraj, Anton Ströh. Abstract. In this paper we answer a question raised in [12] in the affirmative, namely that the essential minimum modulus of an element in a von. Neumann algebra, relative to any norm closed two-sided ideal, is equal to the minimum modulus of the ...

  5. Spin–momenta entanglement in moving frames: Properties of von ...

    Indian Academy of Sciences (India)

    well as locality, of information [9–11]. Expressed differently, the von Neumann entropy measures the stored qubits of information per states of the combined system while the reduced one quantifies the qubits per states that may be stored in one of the subsystems. [1]. It is then obvious that a deeper understanding of von ...

  6. Victor or Villain? Wernher von Braun and the Space Race

    Science.gov (United States)

    O'Brien, Jason L.; Sears, Christine E.

    2011-01-01

    Set during the Cold War and space race, this historical role-play focuses on Wernher von Braun's involvement in and culpability for the use of slave laborers to produce V-2 rockets for Nazi Germany. Students will grapple with two central questions. Should von Braun have been allowed to emigrate to the United States given his affiliation with the…

  7. Von Krahli teatris etenduvad Tõnu Kõrvitsa kammerooperid / Esme Kassak

    Index Scriptorium Estoniae

    Kassak, Esme

    2006-01-01

    20. apr. esietenduvad Von Krahli Teatris Peeter Jalaka lavastuses Tõnu Kõrvitsa uued kammerooperid "Tuleaed" ja "Mu luiged, mu mõtted", mille aluseks on luuletaja Marie Heibergi saatus. Libretode autor on Maarja Kangro. Kammerooperid tulevad lavale Von Krahli Teatri ja Nargen Opera koostöös. Esitavad Kädy Plaas, Helen Lokuta, Nargen Opera koor ja Tallinna Kammerorkester, dirigent Tõnu Kaljuste

  8. von Willebrand disease and aging : an evolving phenotype

    NARCIS (Netherlands)

    Sanders, Y. V.; Giezenaar, M. A.; Laros-van Gorkom, B. A. P.; Meijer, K.; van der Bom, J. G.; Cnossen, M. H.; Nijziel, M. R.; Ypma, P. F.; Fijnvandraat, K.; Eikenboom, J.; Mauser-Bunschoten, E. P.; Leebeek, F. W. G.

    Background: Because the number of elderly von Willebrand disease (VWD) patients is increasing, the pathophysiology of aging in VWD has become increasingly relevant. Objectives: To assess age-related changes in von Willebrand factor (VWF) and factor VIII (FVIII) levels and to compare age-related

  9. En route vers l'harmonisation des diplomes en Europe. La reforme est mise en oeuvre par les presidents d'universite

    CERN Multimedia

    Davidenkoff, E

    2003-01-01

    Hier soir Michel Kaplan vice-president de la Conference des presidents des universites, tirait devant la presse un bilan d'etape tres volontariste de la mise en place du  LMD». Ce sigle designe le nouvel agencement des grades universitaires : L comme licence, M comme master, D comme doctorat (1 page).

  10. Severe Sepsis and Septic Shock Trials (ProCESS, ARISE, ProMISe): What is Optimal Resuscitation?

    Science.gov (United States)

    Osborn, Tiffany M

    2017-04-01

    Between 2014 and 2015, 3 independent, multicenter, randomized controlled trials evaluated early goal-directed therapy (EGDT) in severe sepsis and septic shock: Protocolized Care for Early Septic Shock (ProCESS) from the United States; Australasian Resuscitation in Sepsis Evaluation (ARISE), and Protocolised Management in Sepsis (ProMISe) in the United Kingdom. All 3 trials confirmed that there was no survival benefit of EGDT compared to usual resuscitation. How should we define usual care for sepsis given these study findings? Furthermore, the definition of sepsis has now been updated. This article reviews key findings of these 3 trials and discusses these important issues in sepsis management. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Mise au point de la protection intégrée du colza : exemple du phoma (Leptosphaeria maculans

    Directory of Open Access Journals (Sweden)

    Aubertot Jean-Noël

    2003-05-01

    Full Text Available En France, le phoma est considéré comme la maladie la plus préoccupante du colza. Il n’existe aucune méthode de lutte à la fois efficace, rentable et respectueuse de l’environnement. Il apparaît donc nécessaire de développer la lutte intégrée de la culture contre cette maladie. Cette communication présente les résultats d’un programme de recherche visant à analyser et à modéliser les effets des systèmes de culture sur le développement de la maladie. Des pistes concrètes pour la mise en oeuvre de la lutte intégrée contre le phoma sont proposées.

  12. O EFEITO 3D DO PERÍODO CONVERGENTE NA MISE-EN-SCÈNE DE HOUSE OF WAX

    OpenAIRE

    Durand, Priscilla Barbosa; Universidade Federal de Pernambuco

    2017-01-01

    O objetivo deste artigo é apontar o impacto estético do efeito 3D através da mise-en-scène de House Of Wax (1953) de Andre DeToth, filme do gênero de terror produzido no período convergente da história do cinema em 3D estereoscópico. Defende-se o pressuposto de que essa tecnologia tem o potencial de formar um campo de experimentações cinematográficas, contribuindo para a criação de novas linguagens e experiências estéticas discutindo suas características e sua potencialidade através do impact...

  13. LA MISE EN OEUVRE DE LA METHODE ABC/ABM AU CANADA, EN FRANCE ET AU JAPON. ETUDE COMPARATIVE

    OpenAIRE

    Bescos, Pierre-Laurent; Cauvin, Eric; Gosselin, Maurice; Yoshikawa, Takeo

    2001-01-01

    International audience; Cette communication a pour but d'analyser les résultats d'une enquête internationale sur la mise en oeuvre de la méthode ABC/ABM conduite au Canada, en France et au Japon.. En ce qui concerne la France, nous avons obtenu 111 réponses aux questionnaires envoyés par l'intermédiaire de la DFCG. Sur cet ensemble, 20% des entreprises ont mis en place la méthode et 32% ont un projet en cours ou ont entamé une réflexion sur le sujet. Cette enquête est la première du genre sur...

  14. [Heinz von zur Mühlen. Das Bürgertum Fordert Blut. Ein Bolschewistiches Flugblatt von 1918] / Paul Kaegbein

    Index Scriptorium Estoniae

    Kaegbein, Paul

    2007-01-01

    Arvustus: Heinz von zur Mühlen. Das Bürgertum Fordert Blut. Ein Bolschewistiches Flugblatt von 1918. In : Ostseeprovinzen, baltische Staaten und das Nationale. Münster : LIT, 2005, lk. 403-414. 1918. aastast pärit lendlehest, mille käekirja järgi otsustades on kirjutanud Viktor Kingissepp

  15. Kontextualisierung von Queer Theory Contextualizing Queer Theory

    Directory of Open Access Journals (Sweden)

    Anna Voigt

    2008-03-01

    Full Text Available Christine M. Klapeer legt in diesem Einführungsband dar, aus welchen politischen und theoretischen Kontexten heraus sich ‚queer‘ zu einem Begriff mit besonderem politischem und theoretischem Gehalt entwickelt hat. Wesentlich zielt sie dabei auf eine kritische Kontextualisierung von „queer theory”. Die Autorin geht zunächst auf das Gay Liberation Movement ein, grenzt die Queer Theory vom Poststrukturalismus, von feministischen Theorien und den Lesbian and Gay Studies ab, beleuchtet Eckpunkte queeren Denkens und zeichnet schließlich die Entwicklungen in Österreich sowohl politisch-rechtlich als auch bewegungsgeschichtlich und in der Wissenschaftslandschaft nach.Christine M. Klapeer’s introductory volume demonstrates the manner in which ‘queer’ grew out of various political and theoretical contexts to become a term with special political and theoretical content. She focuses primarily on a critical contextualization of “queer theory.” The author begins by approaching the Gay Liberation Movement and then distinguishes Queer Theory from poststructuralism, from feminist theories, and from Lesbian and Gay Studies. She continues on to illuminate the key aspects of queer thought and concludes by sketching the development in Austria in terms of politics and the law, the history of movements, and within the landscape of knowledge.

  16. Guy von Dardel 1919-2009

    CERN Multimedia

    2009-01-01

    Guy von Dardel, a well-known figure at CERN and in the international particle physics community, passed away on 28 August. Guy von Dardel came to CERN when it was founded in 1954 and was a full-time staff member until 1964, performing several experiments and working on technical developments. These included the first measurement of the neutral pion’s life-time. Called to Lund University in 1964, he became professor there in 1965 and director of the 1.2 GeV electron accelerator. In the late 1960s, he performed an experiment at CERN’s PS that measured the decays of the Λ. Then, in the early 1970s, he involved the Lund group in a series of experiments at the Intersecting Storage Rings (ISR), where he measured the production of various types of particles. In particular, he participated in a series of experiments that observed the production of a high abundance of particles with large transverse momenta. This required an explanation...

  17. Suitability of tracers; Eignung von Tracern

    Energy Technology Data Exchange (ETDEWEB)

    Klotz, D. [GSF - Forschungszentrum fuer Umwelt und Gesundheit GmbH, Neuherberg (Germany). Inst. fuer Hydrologie

    1999-02-01

    Hydrological tracer techniques are a means of making statements on the direction and speed of underground water. One of the simpler tasks is to find out whether there is hydrological communication between two given points. This requires a determination of the direction of flow, which places less exacting demands on the properties of the tracer than does the task of determining the flow velocity of underground water. Tracer methods can serve to infer from flow velocity the distance (flow) velocity, which is defined as the ratio between the distance between two points located in flow direction and the actual time it takes water to flow from one to the other. [Deutsch] Mit Hilfe der hydrologischen Markierungstechniken koennen Aussagen ueber die Richtung und die Geschwindigkeit von Bewegungen des unterirdischen Wassers gemacht werden. Der einfachere Fall liegt vor, wenn festgestellt werden soll, ob zwischen zwei Punkten eine hydrologische Verbindung besteht. Bei dieser Fliessrichtungsbestimmung sind die Forderungen an die Eigenschaften der einzusetzenden Tracer geringer als bei der Bestimmung der Geschwindigkeit des unterirdischen Wassers. Von den Geschwindigkeiten des unterirdischen Wassers ist die Abstands-(Fliess)geschwindigkeit, die definiert ist durch das Verhaeltnis aus dem Abstand und der wahren Fliesszeit zwischen zwei in Bewegungsrichtung gelegenen Punkten, durch Tracermethoden zu bestimmen. (orig.)

  18. Die Krakauer Kirche von Karmeliten und Karmelitaninnen

    Directory of Open Access Journals (Sweden)

    Józef Szymon Wronski

    2004-12-01

    Full Text Available 1. Die Klosterkirche der unbeschuhten Karmelitinnen Zum Heiligen Josef. Ein glücklicher Auftakt und somit die charakteristische Einführung in das 20. Jh. für den Kirchenbau von Krakau war die Errichtung der Karmeliterinnen St. Josephs-Kirche an der Lobzowska-Straße 40, in der die Architekten (Tadeusz Stryjeński (1849-1943 - Projektant der Kirche und Franciszek Mączyński (1874-1947 - Ausführer des Bauprojektes mit eigenen Verbesserungen die historisch- eklektizistischen Formen d.h. die mittelalterlichen Formen vor allem des sog. Übergangsstils vereinfachten. Die Kirche, die in den Jahren 1903-1905 errichtet wurde, steht inmitten vom Baukomplex des Klosters, dessen Grundriss das Quadrat ist49. Der Kirchenbau ist ein dem Gesamtbau des Klosters eingefügter Längsraum. Hinter dem Chor liegt das Oratorium des Konvents. Das Material Backstein (mit Verwendung von Stein erinnert an die Baukunst eines der besten Architekten jener Zeit, nämlich Teodor Talowskis (1857-1910, der viele Kirchen in Südpolen, aber auch viele Bürgerhäuser nicht nur in Krakau im ausgehenden 19. Jh. baute. Die Architektur der Karmeliterinnen St. Josephs-Kirche ist immer noch im Malerischen begriffen. Aber die Vereinfachung der historischen Formen führt zu ihrer „Beruhigung” und dadurch zur Wuchtigkeit des Ausdrucks. Bemerkenswert ist die in dieser Zeit (in der Anlage noch seltene ausgewogene Proportionierung des Baukörpers. Das methodische Prinzip jener Zeit ist der Kontrast. Im Kontrast zu den gedrungenen und wuchtigen Formen des Baukörpers stehen z.B. die sich verjüngenden obeliskenförmigen und pylonenartigen Türmchen, die nicht nur die Eingangsfassade der Kirche flankieren, sondern auch an den Ecken des Querhauses der Kirche stehen. Die ingravierten weißen Steine an der Fassade in der Zahl von Zehn erinnern an das Gebot des Karmelterinnenordens: Bete täglich den Rosenkranz und sind zugleich ein Vanitativmotiv. 2. Die Klosterkirche der unbeschuhten

  19. Von Neumann's quantization of general relativity

    Science.gov (United States)

    Arbuzov, A. B.; Cherny, A. Yu.; Cirilo-Lombardo, D. J.; Nazmitdinov, R. G.; Han, Nguyen Suan; Pavlov, A. E.; Pervushin, V. N.; Zakharov, A. F.

    2017-05-01

    Von Neumann's procedure is applied to quantizing general relativity. Initial data for dynamical variables in the Planck epoch, where the Hubble parameter value coincided with the Planck mass are quantized. These initial data are defined in terms of the Fock orthogonal simplex in the tangent Minkowski spacetime and the Dirac conformal interval. The Einstein cosmological principle is used to average the logarithm of the determinant of the spatial metric over the spatial volume of the visible Universe. The splitting of general coordinate transformations into diffeomorphisms and transformations of the initial data is introduced. In accordance with von Neumann's procedure, the vacuum state is treated is a quantum ensemble that is degenerate in quantum numbers of nonvacuum states. The distribution of the vacuum state leads to the Casimir effect in gravidynamics in just the same way as in electrodynamics. The generating functional for perturbation theory in gravidynamics is found by solving the quantum energy constraint. The applicability range of gravidynamics is discussed along with the possibility of employing this theory to interpret modern observational data.

  20. Translational medicine advances in von Willebrand disease.

    Science.gov (United States)

    Lillicrap, D

    2013-06-01

    Following the recognition of von Willebrand disease (VWD) in 1926 and the cloning of the gene for von Willebrand factor (VWF) in 1985, significant advances have been made in our fundamental knowledge of both the disease and the protein. Some of this new knowledge has also begun to impact the clinical management of VWD. First, the progressive increase in our understanding of the molecular genetic basis of VWD has resulted in rational applications of molecular testing to complement the current range of phenotypic tests for VWD. These molecular genetic strategies are most effectively directed at the prenatal diagnosis of type 3 VWD and confirmatory testing for types 2B and 2N disease. In contrast, the use of molecular testing to clarify the diagnosis of type 1 VWD is of marginal benefit, at best. In terms of VWD therapies, a new recombinant VWF concentrate has recently completed successful clinical trials and is now awaiting more widespread application. There have even been some preclinical successes with VWF gene transfer although the clinical rationale for this therapeutic strategy needs careful consideration. Much more remains to be learnt about the biology of VWF and further translational advances for the enhancement of VWD care will inevitably be realized. © 2013 International Society on Thrombosis and Haemostasis.

  1. Entwicklung von Nickel-Trägerkatalysatoren für die Methanisierung von Kohlenstoffdioxid unter Anwendung von Parallelpräparation und statistischer Versuchsplanung

    OpenAIRE

    Thomys, Oliver Dieter

    2017-01-01

    Die Methanisierung von Kohlenstoffdioxid (Sabatier-Reaktion) gilt als aussichtsreiche Technologie für die chemische Speicherung überschüssigen elektrischen Stroms aus erneuerbaren Energien. Diese Arbeit befasst sich mit der Präparation von Nickel-Trägerkatalysatoren mit hoher Niedrigtemperatur-Aktivität und Langzeitstabilität. Durch Parallelsynthese-Konzepte und Methoden der statistischen Versuchsplanung konnten entsprechende Katalysatoren mit niedriger Metallbeladung präpariert werden, deren...

  2. Alexander von Humboldt in Daniel Kehlmanns Welt

    Directory of Open Access Journals (Sweden)

    Ottmar Ette

    2012-12-01

    Full Text Available Zusammenfassung Wie stark sich im Verlauf des zurückliegenden Vierteljahrhunderts der Bekanntheitsgrad Alexander von Humboldts in der deutschsprachigen Öffentlichkeit verändert hat, zeigen nicht nur Fernsehumfragen zu den berühmtesten Deutschen, in denen Alexander von Humboldt mittlerweile figuriert, oder Fernsehserien, die über aktuelle Expeditionen berichten und auf Humboldts Namen zurückgreifen. Am deutlichsten vielleicht belegt dies der enorme Erfolg von Daniel Kehlmanns Roman Die Vermessung der Welt, der ohne die zuvor skizzierte Entwicklung nicht denkbar gewesen wäre. Es ist vor diesem Hintergrund nicht nur reizvoll, sondern aufschlußreich, sich mit dem großen Erfolg dieses kleinen Romans zu beschäftigen. Worum geht es in Die Vermessung der Welt? Und wie läßt sich das „Phänomen Kehlmann“ aus etwas größerer Distanz erklären? Abstract In the last 25 years, Alexander von Humboldt‘s popularity has radically changed in the german-speaking public opinion. Proof of this are not only television surveys about the most famous germans - in which Alexander von Humboldt now regularly figures - or television series about contemporary expeditions, which constantly refer to Humboldt‘s name; perhaps what most clearly verifies this change is the great success of Daniel Kehlmann‘s novel Die Vermessung der Welt. Without the recent developments outlined above, this novel‘s degree of impact would have been unimaginable. To study the great success of this text against this backdrop is not only attractive, but also revealing. What is Die Vermessung der Welt really about? And how can we explain the „Kehlmann phenomenon“ from a greater distance? Resumen La popularidad de Alejandro de Humboldt ha cambiado profundamente dentro del último cuarto de siglo en la opinión pública de habla alemana. Prueba de esto son no sólo las encuestas televisivas sobre los alemanes más famosos, dentro de las cuales figura en estos momentos Alejandro

  3. Stagnation point von Kármán coefficient.

    Science.gov (United States)

    Dallas, V; Vassilicos, J C; Hewitt, G F

    2009-10-01

    On the basis of various direct numerical simulations (DNS) of turbulent channel flows the following picture is proposed. (i) At a distance y from either wall, the Taylor microscale lambda is proportional to the average distance l(s) between stagnation points of the fluctuating velocity field, i.e., lambda(y)=B(1)l(s)(y) with B(1) constant, for delta(nu) stagnation points varies with height according to n(s)=(C(s)/delta(nu)(3))y(+)(-1) where y(+) identical with y/delta(nu) and C(s) is constant in the range delta(nu) stagnation point von Kármán coefficient. (iv) In the limit of exceedingly large Reynolds numbers Re(tau) identical with delta/delta(nu), large enough for the Reynolds stress -(uv) to equal u(tau)(2) in the range delta(nu) < y < delta, and assuming that production of turbulent kinetic energy balances dissipation locally in that range and limit, the mean velocity U(+), normalized by u(tau), obeys (d/dy)U(+) approximately equal to 2/3(E(+)/kappa(s)y) in that same range. (v) It follows that the von Kármán coefficient kappa is a meaningful and well-defined coefficient and the log law holds in turbulent channel/pipe flows only if E(+) is independent of y(+) and Re(tau) in that range, in which case kappa approximately kappa(s). (vi) In support of (d/dy)U(+) approximately equal to 2/3(E(+)/kappa(s)y), DNS data of turbulent channel flows which include the highest currently available values of Re(tau) are best fitted by E(+) approximately equal to 2/3(B(4)y(+)(-2/15)) and (d/dy(+))U(+) approximately equal to (B(4)/kappa(s))y(+)(-1-2/15) with B4 independent of y in delta(nu) < y < delta if the significant departure from -(uv) approximately equal to u(tau)(2) at these Re(tau) values is taken into account.

  4. Die Rolle von RANK-Ligand und Osteoprotegerin bei Osteoporose

    Directory of Open Access Journals (Sweden)

    Hofbauer LC

    2004-01-01

    Full Text Available Receptor activator of nuclear factor (NF- κB ligand (RANKL, sein zellulärer Rezeptor RANK und der Decoy-Rezeptor Osteoprotegerin (OPG stellen ein essentielles Zytokinsystem für die Zellbiologie von Osteoklasten dar. Verschiedene Untersuchungen belegen die Bedeutung von Störungen des OPG/RANKL/RANK-Systems bei der Pathogenese metabolischer Knochenerkrankungen. In dieser Arbeit werden die wichtigsten Störungen des OPG/RANKL/RANK-Systems bei verschiedenen Osteoporoseformen dargestellt. Östrogenrezeptor- (ER- Agonisten wie 17 β-Östradiol, Raloxifen und Genistein stimulieren die osteoblastäre Produktion von OPG durch Aktivierung von ER- α in vitro, während Lymphozyten von Patientinnen mit Östrogenmangel RANKL überexprimieren. Die parenterale Gabe von OPG vermag den mit Östrogenmangel assoziierten Knochenverlust im Tiermodell und in einer kleineren klinischen Studie zu verhindern. Glukokortikoide und Immunsuppressiva steigern gleichzeitig die RANKL-Expression und hemmen die OPG-Produktion in osteoblastären Zellen in vitro. Glukokortikoide sind auch in vivo imstande, die OPG-Serumspiegel deutlich zu reduzieren. Dagegen hemmen biomechanische Reize in vitro die RANKL-Produktion und steigern die OPG-Produktion. Ein Fehlen dieser biomechanischen Reize bei längerer Immobilisierung kann daher den RANKL/OPG-Quotienten steigern, während die tierexperimentelle Immobilisierungs-Osteoporose durch die parenterale Gabe von OPG gemildert werden kann.

  5. Drei Dimensionen von filmischem Archivmaterial. Die Untersuchung von Archivfilmen aus der Zeit des Holocaust

    Directory of Open Access Journals (Sweden)

    Tobias Ebbrecht-Hartmann

    2017-04-01

    Full Text Available Filmisches Archivmaterial aus der Zeit des Holocaust ist eine ambivalente Quelle. Daher sind spezifische Ansätze notwendig, um dieses Material zu ‘lesen’. Es geht darum, den besonderen Inhalt der Bilder zu analysieren, den Kontext ihrer Entstehung zu bestimmen, aber auch, ihre spätere Verwendung und Zirkulation in der visuellen Kultur und damit auch ihren wechselnden Status mit einzubeziehen. Am Beispiel ausgewählter Filmfragmente aus dem Warschauer Ghetto und dem Ghetto Theresienstadt skizziert der Artikel einen Ansatz, wie man diese drei Dimensionen von filmischem Archivmaterial analysieren kann und schlägt damit eine entsprechende Historiographie von Archivfilmen aus der Zeit des Holocaust vor.

  6. Modellierung von Angebots- und Nachfrageverhalten zur Analyse von Agrarpolitiken: Theorie, Methoden und empirische Anwendungen

    OpenAIRE

    Henningsen, Arne

    2006-01-01

    Die Analyse der Auswirkungen von Agrarpolitiken ist in der Regel sehr komplex und erfordert eine detaillierte Modellierung des Angebots- und Nachfrageverhaltens im Agrarsektor. Eine empirische Anwendung setzt daher eine angemessene ökonomische Theorie sowie fortgeschrittene quantitative Methoden voraus. Alle neun Aufsätze dieser Dissertation lassen sich in diese Themengebiete einordnen. Zunächst werden die Nachfrage nach Bananen und die Folgen der EU Bananenmarktordnung für deutsche Konsument...

  7. Charakterisierung von Mutanten im Lösungsmittelstoffwechsel von Clostridium acetobutylicum

    OpenAIRE

    Hönicke, Daniel

    2015-01-01

    Im Rahmen dieser Arbeit wurden insgesamt neun durch ClosTron-basierte Mutagenese erhaltene Insertionsmutanten von C. acetobutylicum ATCC 824 einer umfangreichen Charakterisierung unterzogen. Für alle im Batch-Fermentationsmaßstab und/oder in kontinuierlicher Kultur fermentierten Stämme erfolgte eine globale Analyse des Transkriptoms unter Verwendung der DNA-Microarray-Technologie. Für eine Analyse des Acetat- und Aceton-Stoffwechsels wurden Stämme mit einer inaktivierten Phosphotransacetyl...

  8. Informationssuchverhalten als Grundlage für die Gestaltung von Veranstaltungen zum Erwerb von Informationskompetenz

    Directory of Open Access Journals (Sweden)

    Martin Wollschläger-Tigges

    2015-09-01

    Full Text Available Für die Gestaltung bibliothekarischer Veranstaltungen zum Erwerb von Informationskompetenz stellen die bisherigen Ergebnisse und Befunde der Forschung zum Informationssuchverhalten eine wertvolle Grundlage dar, indem bestimmte und v.a. typische Verhaltensmuster, Routinen und Präferenzen im Umgang mit Informationsressourcen und Informationen in konzeptionelle und inhaltliche Anpassungen von IK- Veranstaltungen eingebracht und eingesetzt werden. Das Informationssuchverhalten untersucht sowohl individuelle als auch kollektive Informationsprozesse und Faktoren, die diese maßgeblich beeinflussen. Hierzu werden der gesamte Informationsprozess oder einzelne Abschnitte untersucht, die den Information Need, Seeking und Using (INSU-Prozess bilden. Die Befunde der einzelnen INSU-Prozesses-Einheiten zeigen, dass Faktoren wie Informationsbedarf, Informationsart und -form sowie die Einbindung in übergeordnete Arbeitsprozesse wesentlichen Einfluss auf das Informationssuchverhalten haben. Des Weiteren konnte die ISB-Forschung eine Klassifizierung von Benutzergruppen entwickeln und z.B. Fast Surfers, Broad Scanners und Deep Divers charakterisieren bzw. auch das Bouncing oder Flicking Behavior beschreiben. Hinzu kommen mehrere Modelle, die Informationssuchverhalten und Informationsverhalten in bestimmten Situationen nachbilden und darstellen können.

  9. Tragverhalten von Verbunddübeln unter Zugbelastung

    OpenAIRE

    Appl, Jörg-Jochen

    2009-01-01

    Im Bauwesen werden in zunehmendem Maße Dübel zur Einleitung von Lasten in den erhärteten Beton eingesetzt. Vor allem Befestigungssysteme auf der Grundlage chemischer Mörtel werden vermehrt verwendet. Allerdings fehlte bisher ein genügend genaues Berechnungsmodell zur Bemessung von beliebigen Befestigungen mit Verbunddübeln für unterschiedliche Verankerungstiefen und für verschiedene Verbundfestigkeiten. In der vorliegenden Arbeit wurde das Tragverhalten von Verbundübeln unter Zugbelastung...

  10. A von Bertalanffy growth model with a seasonally varying coefficient

    Science.gov (United States)

    Cloern, James E.; Nichols, Frederic H.

    1978-01-01

    The von Bertalanffy model of body growth is inappropriate for organisms whose growth is restricted to a seasonal period because it assumes that growth rate is invariant with time. Incorporation of a time-varying coefficient significantly improves the capability of the von Bertalanffy equation to describe changing body size of both the bivalve mollusc Macoma balthicain San Francisco Bay and the flathead sole, Hippoglossoides elassodon, in Washington state. This simple modification of the von Bertalanffy model should offer improved predictions of body growth for a variety of other aquatic animals.

  11. Abenteuer Alexander-von-Humboldt-Bibliographie

    Directory of Open Access Journals (Sweden)

    Christian Suckow

    2002-04-01

    Full Text Available Article in German; Abstracts in English and German.The two attempts (1860 and 1872 to compile a bibliography of all works of Alexander von Humboldt have to be regarded as failures. Due to Humboldt’s scientific methods, the contemporary popularity of his writings, and the conditions of book publishing and selling, it has been difficult to achieve an overview of his œuvre. Thus each attempt to write a reliable or at least partially complete bibliography of Humboldt’s works constituted an adventure. Horst Fiedler and Ulrike Leitner have mastered this undertaking. As a result of their efforts over more than two decades, a bibliography of those works by Humboldt which were published in book form appeared in the year 2000.

  12. Johann von Lamont: A Pioneer in Geomagnetism

    Science.gov (United States)

    Soffel, Heinrich

    2006-06-01

    The 200th birthday of John Lamont (1805-1879, Figure 1), a pioneer in the study of geomagnetism, was marked on 13 December 2005. Lamont founded the Munich Geomagnetic Observatory in 1840 and was a member of the group of scientists including Carl Friedrich Gauss, Alexander von Humboldt, Eduard Sabine, Jonas Angstrøm, Humphret Lloyd, Adolf Kupffer, Karl Kreil, and Adolphe Quetelet who composed the Göttingen Magnetic Union. They organized an international network of geomagnetic observatories [Barraclough et al., 1992]. The present knowledge of the geomagnetic field and its secular variation is largely based on the data collected by the global network of geomagnetic observatories during the last 170 years. Lamont's talents and his dedication and enthusiasm for discovery are reflected in the depth and scope of his contributions to a broad variety of natural sciences such as astronomy, meteorology, geomagnetism, and geodesy. However, this article just touches on his merits in geomagnetism.

  13. Bertha von Suttner 1843-1914

    OpenAIRE

    Hoock-Demarle, Marie-Claire; Hessel, Stéphane

    2016-01-01

    Née dans « le monde d'hier » cher à son compatriote Stefan Zweig, morte le 21 juin 1914 à la veille du déclenchement d’une guerre qu’elle appelle Weltkrieg, Bertha von Suttner témoigne d’un parcours hors du commun dans un moment crucial où s’amorcent les conflits générés par les militarismes et les nationalismes menant inexorablement à la catastrophe. Arpenteuse d’Europe, voyageuse du Nouveau Monde, elle voit dans « l’américanisation du monde » une raison de construire dans la paix et la coop...

  14. Modernisation of ventilation systems; Modernisierung von Lueftungsanlagen

    Energy Technology Data Exchange (ETDEWEB)

    Richter, W. [Technische Univ. Dresden (Germany). Inst. fuer Thermodynamik und Technische Gebaeudeausruestung

    1997-12-31

    When redeveloping buildings it is common to use window constructions with air-tight rabbets which obviate the inflow of fresh air almost entirely. This leads to the well-known structural-physics and hygienic consequences. As an added effect, the distinctly enhanced thermal insulation results in changes in dynamic heat loss. The paper focuses on the issues of how to safeguard the inflow of fresh air, and the heating capacity of radiators. (MSK) [Deutsch] Da die bei Gebaeudesanierungen eingesetzten fugendichten Fensterkonstruktionen die Nachstroemmoeglichkeiten fuer die Zuluft fast ganz unterbinden, fuehrt das zu den bekannten bauphysikalischen und hygienischen Konsequenzen. Dazu kommen veraenderte dynamische Waermverlustverhaeltnisse aufgrund der deutlich verbesserten Waermedaemmung. Im Folgenden wird schwerpunktmaessig auf die Probleme Zuluftsicherung und Waermeleistung von Heizkoerpern eingegangen.

  15. Hepatische Effekte von Wachstumshormon auf den Glukosestoffwechsel

    Directory of Open Access Journals (Sweden)

    Rufinatscha K

    2015-01-01

    Full Text Available Untherapierter Wachstumshormonmangel im Erwachsenenalter (AGHD ist mit viszeraler Adipositas, Dyslipidämie, Insulinresistenz und Fettleber verbunden. Interessanterweise finden sich viele der AGHD-Merkmale auch bei Patienten mit metabolischem Syndrom. Die nichtalkoholische Fettlebererkrankung (NAFLD gilt als hepatische Manifestation des metabolischen Syndroms. In einigen Studien wurden bei Patienten mit NAFLD verminderte Konzentrationen von zirkulierendem IGF-1, dessen Synthese zu einem großen Teil durch Wachstumshormon (GH reguliert wird, beschrieben. Mäuse, welche eine hepatische Wachstumshormondefizienz aufweisen, zeigen zahlreiche phänotypische Charakteristika des metabolischen Syndroms, unter anderen auch eine Fettlebererkrankung. Dies legt einen Zusammenhang zwischen dem Wachstumshormon und der Entstehung einer NAFLD nahe. Ziel unserer Studie ist es, in einem Zellkulturmodell die Effekte des Wachstumshormons auf den intrazellulären Glukosestoffwechsel näher zu untersuchen. Im Detail sollen Auswirkungen einer verminderten Wachstumshormonrezeptorexpression auf den Insulinsignaltransduktionsweg, den Glykogengehalt und auf Schlüsselenzyme der Glukoneogenese untersucht werden. Präliminäre Daten zeigen, dass eine verminderte Wachstumshormonrezeptorexpression mit intrazellulären Veränderungen des hepatischen Glukosestoffwechsels verbunden ist. Die verminderte Insulinsensitivität könnte auf Alterationen im Insulinsignaltransduktionsweg und Änderungen der Glukoneogenese zurückzuführen sein. Diese präliminären Daten weisen darauf hin, dass Wachstumshormon einen direkten Einfluss auf den Glukosestoffwechsel in der Leber hat. Zudem legen sie nahe, dass Veränderungen im Wachstumshormonstoffwechsel einen wichtigen pathophysiologischen Mechanismus in der Entstehung der Fettlebererkrankung bei Patienten mit metabolischem Syndrom darstellen könnten. Der folgende Artikel soll einen kurzen Überblick über die Effekte von Wachstumshormon

  16. VON WILLEBRAND DISEASE: DIAGNOSIS AND TREATMENT

    Directory of Open Access Journals (Sweden)

    Majda Benedik Dolničar

    2004-12-01

    Full Text Available Background. Von Willebrand disease (VWD is a most frequently inborn bleeding disorder caused by quantitative or qualitative defects of von Willebrand factor (VWF. VWF promotes platelet-vessel wall (adhesion and plateletplatelet interaction (aggregation. It is also the carrier for factor VIII (F VIII in plasma. A deficiency of VWF may results in impairment of both, primary and secondary haemostasis. Therefore, patients with VWD can have bleeding symptoms typical fot the defect in primary haemostasis (mucocutaneous haemorrhages. In severe deficiency of VWF there are also haemarthroses and haematomas typical for patients with coagulation defects. Several types and subtypes of VWD have been described. The diagnosis is based on measurements of VWF concentration and activity and F VIII activity in plasma. The tests identifying VWD subtypes are ristocetin induced platelet agglutination (RIPA, multimeric analysis of VWF and measurement of the binding of VWF to F VIII.Conclusions. Due to heterogeneity of VWF defects, the correct diagnosis of types and subtypes is sometimes difficult but is important for appropriate treatment. There are two main therapeutic options for patients with VWD: desmopressin and blood derived concentrates of F VIII/VWF. In certain cases antifibrinolytics and hormones can be suitable treatment. Desmopressin is the treatment of choice in patients with type 1 VWD. It raises endogenous F VIII and VWF and thereby corrects the intrinsic coagulation defect as well as the prolonged bleeding time (BT or closure time (CT-PFA100 in most type 1 VWD patients. In type 3 and in the majority of type 2 patients desmopressin is not effective and it is necessary to use concentrates containing F VIII and VWF. These are always effective in raising of F VIII activity, whereas the BT/CT may not be completely corrected, but the normalisation of the BT/CT is not always necessary.

  17. Traduction de la particule de mise en relief slovène tudi en français: cas de disparitions surprenantes

    Directory of Open Access Journals (Sweden)

    Jacqueline Oven

    2010-12-01

    Full Text Available La présente contribution se propose d'analyser les cas de disparitions de la particule de mise en relief slovène tudi dans les traductions françaises. Dans le corpus choisi (le roman Alamut de V. Bartol et sa traduction française, nous avons constaté la non-traduction de la particule slovène dans presque un tiers des cas. Le lexème tudi est caractérisé par deux fonctions : la mise en relief et la connexion. Sur le plan sémantique, il renferme un sème minimal, à savoir l'addition. L'analyse des exemples présentant des cas de non-traduction de la particule slovène tudi en français a abouti aux conclusions suivantes: il y a non-traduction quand le contexte immédiat inclut un autre élément exprimant déjà l'addition. La réintroduction du lexème aussi (l'équivalent le plus fréquent de la particule tudi s'avère être redondante, sans pour autant, dans la grande majorité des cas, affecter l'acceptabilité, voire la grammaticalité de la phrase. Le rajout du lexème aussi rend la phrase agrammaticale dans seulement deux cas de figure : quand l'addition exprime l'élément terminal d'une liste et quand le contexte minimal renferme déjà une autre particule de mise en relief (sl. tudi že - fr. * aussi déjà. D'un point de vue contrastif, nous constatons que tudi et aussi assument les deux mêmes fonctions (mise en relief et connexion dans les deux langues, avec néanmoins une différence majeure au niveau de la combinatoire : alors que la particule slovène tudi assure la mise en relief et/ou la connexion, le lexème aussi, lui, ne peut être que moyen de mise en relief et de connexion. Le français évite toute forme de redondance sémantique, tout en excluant la redondance fonctionnelle, alors que le slovène permet ces cas de figure.

  18. Von Krahli Teatri lavastus pääses tippfestivalile

    Index Scriptorium Estoniae

    1999-01-01

    Von Krahli Teatri uuendatud lavastus "Eesti mängud. Pulm" esietendub festivalil Theater Der Welt Berliinis. Peeter Jalaka multimeediaetendus Eesti ajaloost ja traditsioonidest osaleb ka suveteatrite festivalil Hamburgis, seejärel antakse kuus etendust Amsterdamis

  19. La actualidad del pensamiento de Carl von Clausewitz

    National Research Council Canada - National Science Library

    Borrero Mansilla, Armando

    2003-01-01

    The article presents the validity of the thought of Carl von Clausewitz, which application, beyond the wars among national States, can be extended to the analysis of the confrontation among political...

  20. Lexikon lesbischer Frauen im Film von Daniela Sobek

    Directory of Open Access Journals (Sweden)

    Karin Windt

    2002-03-01

    Full Text Available Das Lexikon stellt ein neues Basiswerk über lesbische Figuren im Film dar. Neben zahlreichen Artikeln von Anbeginn der Filmgeschichte bis heute gibt es Features über bekannte Schauspielerinnen und lesbische role models.

  1. Magnus Georg von Paucker (1787-1855) / Eckhard Spring

    Index Scriptorium Estoniae

    Spring, Eckhard

    2013-01-01

    Eestis sündinud ja Tartu Ülikoolis õppinud silmapaistvast baltisaksa teadlasest ja tema lapselapsest Alexandrine Pauckerist. 23. novembril 2012 Jelgavas/Mitaus toimunud Magnus Georg von Pauckerile pühendatud teaduskonverentsist

  2. Von Krahli Teater toob Eestisse erakordse auhinna / Tiit Tuumalu

    Index Scriptorium Estoniae

    Tuumalu, Tiit, 1971-

    2004-01-01

    Bessie-auhinna puhul, millega New Yorgis pärjati Von Krahli Teatri lavastust "Luikede järv." Mõjukuselt on seda võrreldud Broadway teatriauhinna Tonyga. Lisatud lühiandmed P. Jalaka ja S. Pepeljajevi kohta

  3. Politische Bildung im Kontext von Regierung, Unterricht und Zucht

    National Research Council Canada - National Science Library

    Thomas Rucker

    2014-01-01

    .... In diesem Beitrag wird zu zeigen versucht, dass Herbart die Unterstützung politischer Bildung als eine Aufgabe von Regierung, Unterricht und Zucht bestimmt und in seinem Werk wichtige „Bausteine...

  4. Revascularization Operation for Moyamoya Disease with Concurrent von Willebrand Disease.

    Science.gov (United States)

    Miki, Kenji; Arimura, Koichi; Nishimura, Ataru; Yoshimoto, Koji; Sayama, Tetsuro; Iihara, Koji

    2017-12-01

    Although extracranial-intracranial (EC-IC) bypass is an effective treatment strategy for symptomatic moyamoya disease, surgeons need to be cautious regarding the possibility of postoperative hemorrhagic complications in patients with a concurrent coagulation disorder. Here, we describe a case of EC-IC bypass for moyamoya disease concurrent with von Willebrand disease type 1. Following perioperative replacement of the von Willebrand factor, the patient showed an uneventful and uncomplicated clinical course. This is the first reported case of EC-IC bypass being performed for moyamoya disease in a patient with concurrent von Willebrand disease. We emphasize the importance of appropriate management with replacement of the von Willebrand factor during the perioperative period to avoid hemorrhagic complications. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. Die zentrale Wirkung von Candesartan in der Schlaganfalltherapie

    OpenAIRE

    Maydowski, Katja

    2011-01-01

    Ziel der vorliegenden Arbeit war es, die Auswirkungen des AT1-Blockers Candesartan auf einen ischämischen Insult durch eine rein zentrale AT1-Blockade am Tiermodell mit direkter intracerebroventrikulärer Applikation von Candesartan zu untersuchen.

  6. Zur sportlichen Laufbahn von Marathonläufern

    OpenAIRE

    Rümmele, Edgar

    1984-01-01

    Zur sportlichen Laufbahn von Marathonläufern : e. Beitr. zur Psychologie d. Marathonläufers. - Thun u.a. : Deutsch, 1984. - 253, 14 S. - Zugl.: Tübingen, Univ., Diss. - (Beiträge zur Sportwissenschaft ; 1)

  7. Warum das Controlling den systematischen Einsatz von Simulationen vorantreiben sollte

    DEFF Research Database (Denmark)

    Spitzner, Jan; Schneider, Melanie L.

    2017-01-01

    Simulationen werden in der Unternehmenssteuerung heutzutage noch nicht systematisch eingesetzt. Dass sich jedoch die existierenden Hemmnisse durchaus überwinden lassen, legen die Antworten von Studienteilnehmern nahe, die Simulationen häufig einsetzen. Dabei kann Controlling eine Vorreiterrolle e...

  8. Von Krahli Teater viis Helsingisse kaks menulavastust / Andres Laasik

    Index Scriptorium Estoniae

    Laasik, Andres, 1960-2016

    2003-01-01

    Von Krahli Teater esineb 29. nov. Helsingis "Baltic Circle" festivalil lavastustega "Luikede järv" ja "Taksojuhid". Tutvustatakse lühidalt ka paari olulisemat soome lavastust ("Puksiirabi" ja "Hamlet"), mis tulevad festivalil esitamisele

  9. New Danish standards for water treatment in district heating systems; Neue daenische Vorschriften fuer die Behandlung von Wasser in Fernwaermesystemen

    Energy Technology Data Exchange (ETDEWEB)

    Kristensen, O. [Hydro-X A/S, Hjallerup (Denmark)

    2000-12-01

    In 1999 Danske Fjernvarmevaerkers Forening (Danish District Heating Association) updated the recommendations for water treatment for the third time which applied to feed and circulation water in at district heating plants in Denmark. It must however be stressed that no aluminium should be allowed in the system. The following recommended values apply. (orig.) [German] In Daenemark sind viele Fernwaermesysteme von energieverschwendender Kesselsteinbildung oder zerstoerender Korrosion der Rohre betroffen. Dies wurde von unzulaenglicher oder mangelhafter Behandlung des Wassers verursacht. Bei der Modernisierung aelterer Fernwaermesysteme stand die Verbesserung der Wasserqualitaet oft an erster Stelle, noch bevor irgendwelche Reparaturen an Teilabschnitten der Anlage durchgefuehrt wurden. Denn eine lange Leistungszeit kann nur dann erwartet werden, wenn die Qualitaet des Wassers die notwendigen Anforderungen erfuellt. (orig.)

  10. Zur Dialektik von Soft Skills und fachlicher Kompetenz

    OpenAIRE

    Jendrowiak, Hans-Werner

    2010-01-01

    [Der Autor stellt folgende Thesen zur Dialektik von Soft Skills und fachlicher Bildung auf:] 1. Soft Skills sind normale Bildungskategorien und Teil einer Allgemeinen Bildung. […] 2. Soft Skills sind als personalgebundene Kriterien auch immer schon Gegenstand bildungstheoretischer Debatten. […] 3. Soft Skills ist eine trendorientierte Bezeichnung für Bildung. […] 4. Soft Skills sind Ausdruck von Vorstellungen, Ideen und Theorien (Schulkultur, Unternehmenskultur, Unternehmensphilosophie). 5. S...

  11. Behandlung von Cybermobbing durch die Soziale Arbeit in der Schule

    OpenAIRE

    Dill, Irina; Wahl, Lisa

    2015-01-01

    Gegenstand dieser Arbeit ist die Behandlung von Cybermobbing durch die Soziale Arbeit in der Schule. Cybermobbing ist eine neuere Form von schulischer Gewalt und verlangt nach neuen Formen der Beratung und Intervention der Sozialen Arbeit in der Schule. Anhand einer Literaturrecherche gehen die Autorinnen Lisa Wahl und Irina Dill der Frage nach, inwiefern die Soziale Arbeit in der Schule Cybermobbing behandeln kann. Die Konzipierung der Sozialen Arbeit in der Schule fundiert primär auf dem Bu...

  12. Zusammenhang von Prozess, Mikrostruktur, Eigenspannungen und Eigenschaften bei Aluminiumverbundwerkstoffen

    OpenAIRE

    Kachold, Franziska

    2016-01-01

    Wo die mechanische Leistungsfähigkeit von monolithischen Materialien an ihre Grenzen stößt, bieten Verbundwerkstoffe neue Perspektiven. Besonders wenn hohe Festigkeit oder Steifigkeit bei gleichzeitig niedrigem spezifischen Gewicht gefordert ist, kommen Faserverbundwerkstoffe zum Einsatz. Faserverstärkte Polymere existieren bereits seit ca. 1900 und werden heute für ein breites Spektrum von Bauteilen und Produkten im Automobil-, Flugzeug- und auch Sportgerätebau verwendet. Die geringe T...

  13. Von Neumann's impossibility proof: Mathematics in the service of rhetorics

    Science.gov (United States)

    Dieks, Dennis

    2017-11-01

    According to what has become a standard history of quantum mechanics, in 1932 von Neumann persuaded the physics community that hidden variables are impossible as a matter of principle, after which leading proponents of the Copenhagen interpretation put the situation to good use by arguing that the completeness of quantum mechanics was undeniable. This state of affairs lasted, so the story continues, until Bell in 1966 exposed von Neumann's proof as obviously wrong. The realization that von Neumann's proof was fallacious then rehabilitated hidden variables and made serious foundational research possible again. It is often added in recent accounts that von Neumann's error had been spotted almost immediately by Grete Hermann, but that her discovery was of no effect due to the dominant Copenhagen Zeitgeist. We shall attempt to tell a story that is more historically accurate and less ideologically charged. Most importantly, von Neumann never claimed to have shown the impossibility of hidden variables tout court, but argued that hidden-variable theories must possess a structure that deviates fundamentally from that of quantum mechanics. Both Hermann and Bell appear to have missed this point; moreover, both raised unjustified technical objections to the proof. Von Neumann's argument was basically that hidden-variables schemes must violate the ;quantum principle; that physical quantities are to be represented by operators in a Hilbert space. As a consequence, hidden-variables schemes, though possible in principle, necessarily exhibit a certain kind of contextuality. As we shall illustrate, early reactions to Bohm's theory are in agreement with this account. Leading physicists pointed out that Bohm's theory has the strange feature that pre-existing particle properties do not generally reveal themselves in measurements, in accordance with von Neumann's result. They did not conclude that the ;impossible was done; and that von Neumann had been shown wrong.

  14. Möglichkeiten und Grenzen von Social Media Marketing

    OpenAIRE

    Kreutzer, Ralf T.; Hinz, Jule

    2010-01-01

    In diesem Arbeitspapier wird das Konzept des Social Media Marketing theoretisch dargestellt und seine Möglichkeiten und Grenzen analysiert. Dabei werden die einzelnen Instrumente des Social Media Marketings sowie die verschiedenen Nutzertypen erläutert und auf die Erfolgsmessung von Methoden des Social Media Marketings eingegangen. Schließlich wird an den Beispielen HUGO BOSS, Starbucks und Nestlé auf die Umsetzung von Maßnahmen des Social Media Marketings eingegangen und aufgezeigt, welche E...

  15. Rekonstruktion von Gletscherschwankungen mit Hilfe fossiler Hölzer

    OpenAIRE

    Holzhauser, H.

    1984-01-01

    Im vorliegenden Artikel wird gezeigt, wie mit Hilfe von fossilen Hölzern aus dem Gletschervorfeld minimale Gletscherausdehnungen und Gletschervorstöße erfaßt werden können. Einige zeitgenössische Berichte und Zeichnungen aus der Zeit um 1850, als die Alpengletscher ihren letzten neuzeitlichen Hochstand erreichten, sollen veranschaulichen, wie Gletscher in bewaldetes Gebiet vordrangen und Bäume umdrückten. Es wird im weiteren kurz auf die Lage von fossilem Holz im Gletschervo...

  16. Nationale Kapitalanlagengarantien als Instrumente zur Förderung von Direktinvestitionen

    OpenAIRE

    Stern, Thomas

    1988-01-01

    Wegen ihres hohen entwicklungspolitischen Stellenwertes ist die Steigerung von Direktinvestitionen als langfristiges Instrument zur Verbesserung der Verschuldenssituation der Länder der Dritten Welt anerkannt. Trotz dieser Erkenntnis blieben die Direktinvestitionen in Richtung der Entwicklungsländer in den letzten fünf Jahren hinter den Erwartungen zurück und erreichten lediglich einen Anteil von ca. 12 % an den Gesamtkapitalströmen. Wichtige Motive für die Zurückhaltung der Investoren in die...

  17. Kommunale Versorgung, Verortung und Steuerung von Risiken psychischer Gesundheit

    OpenAIRE

    Warner, Joanne

    2006-01-01

    Das Risikokonzept ist heute zentral für alle Bereiche von gesundheitlicher und sozialer Wohlfahrt in Großbritannien. Im Bereich psychischer Gesundheit und insbesondere seit den Maßnahmen zur kommunalen Versorgung in den 1990er Jahren kommt dem Konzept jedoch besondere Aufmerksamkeit zu. Dabei kamen bisher vor allem die Risiken in den Blick, die von Personen mit psychischen Erkrankungen oder in psychischer Not ausgehen, aber nicht die Risiken, mit denen diese selbst konfrontiert sind. Der vorl...

  18. Untersuchung der verfahrenstechnischen Potentiale von CO2-Minderungsoptionen

    OpenAIRE

    Geng, Jin

    2017-01-01

    Die vorliegende Arbeit beschäftigt sich mit der Untersuchung der verfahrenstechnischen Potentiale von CO2-Minderungsoptionen. CO2 ist ein Treibhausgas und führt zu Klimaproblemen. Wie erfolgreich der Kampf gegen den Klimawandel ist, hängt stark von den politischen Entscheidungen ab, welche auf internationalen Vereinbarungen und der wirtschaftlichen Situation basieren. Allerdings ist die technische Machbarkeit die Voraussetzung aller Entscheidungen. In der Arbeit wird diskutiert, welches P...

  19. CyLaw-Report V : "Sicherheit von ec-Karten"

    OpenAIRE

    Schmid, Viola

    2008-01-01

    Entscheidung des BGH vom 05.10.2004 - XI ZR 210/03 Die vorliegende Entscheidung des Bundesgerichtshof (BGH) bringt - nach jahrelanger juristischer Diskussion und divergierender Rechtsprechung verschiedener Gerichte - weiteren Aufschluss bei beweis- und haftungsrechtlichen Fragen von ec-Karten. Die besondere Bedeutung bargeldloser Zahlungsverfahren im Bereich von eCommerce, eGovernment etc. machen das Urteil des BGH zu einer für das Cyberlaw interessanten Entscheidung.

  20. Hochtemperaturverhalten von Stahlbetonplatten mit Textilbetonverstärkung

    OpenAIRE

    Hothan, Sascha; Ehlig, Daniel

    2011-01-01

    Die Verwendung von Endlosfilamenten aus Carbon als Bewehrungsmaterial für Beton, sogenannter Textilbeton, bietet die Möglichkeit der Sanierung und der Verstärkung bestehender Stahlbetonkonstruktionen. Dabei muss die Frage nach dem Feuerwiderstand von derart verstärkten Tragwerken beantwortet werden. Aufschluss darüber liefern Brandversuche. Mit Textilbeton verstärkte Stahlbetonplatten haben in Brandversuchen nach der Einheits- Temperaturzeitkurve bei 33 % der Traglast mehr als 60 Minuten stan...

  1. Expression von Wachstumsfaktoren unter Vakuumversiegelungstherapie in chronischen Wunden

    OpenAIRE

    Rosenberg, Birgit

    2012-01-01

    Hintergründe und Zielsetzung Die Vakuumversiegelungsmethode (V.A.C.® = Vac.) ist ein von M. Morykwas und C. Argenta 1988 entwickeltes Verfahren zur Konditionierung von akuten und chronischen Wunden, das sich in den letzten Jahren klinisch etabliert und dessen Anwendungsspektrum kontinuierlich zugenommen hat. In vielen klinischen Studien konnte die Wirksamkeit dieses Therapieverfahrens in der Wundbehandlung nachgewiesen werden, unklar ist jedoch bislang welche physiologischen Veränderungen auf...

  2. Nash y von Neumann: mundos posibles y juegos de lenguaje

    Directory of Open Access Journals (Sweden)

    Salazar , Boris

    2004-06-01

    Full Text Available Este ensayo emplea las nociones de juego de lenguaje y de equivalencia entre juegos para examinar la decisión de John Nash de no jugar el juego coalicional que propuso John von Neumann. El argumento central es que Nash concibió una clase de mundos posibles incompatible con la de von Neumann, y que en el origen de esa divergencia estarían sus distintas nociones de racionalidad.

  3. Entwicklung von Cellulosefaser-Leichtbeton und Untersuchung des bruchmechanischen Verhaltens

    OpenAIRE

    Thiel, Thomas

    2016-01-01

    Im Zentrum der vorliegenden Arbeit steht ein zementgebundener Leichtbeton auf der Basis von aus Altpapier herausgelösten Cellulosefasern; hierfür wird im Folgenden die Bezeichnung CFLC (Cellulose-Fibre Lightweight Concrete) verwendet. Die Intention zur Untersuchung dieses mitunter auch als Papercrete bezeichneten und bislang nur verhältnismäßig wenig erforschten Materials beruht insbesondere darauf, dass von einer Kombination eines leicht verfügbaren pflanzlichen Faserstoffs mit einem mineral...

  4. Ludwig von Bertalanffy Forerunner of Evolutionary Systems Theory

    OpenAIRE

    Wolfgang, Hofkirchner

    2005-01-01

    Ludwig von Bertalanffy is known as founding father of the General System Theory (GST). When Ludwig von Bertalanffy created his GST amidst the last century, he was able to overcome the deep cleft between the controversial theoretical approaches to biology - mechanicism and vitalism. He did so by formulating laws of organisation ruling biota and after generalising them he successfully applied them to different domains such as medicine, psychology, psychotherapy. Methodologically, Bertalanffy re...

  5. Optimized sampling of hydroperoxides and investigations of the water vapour dependence of hydroperoxide formation during ozonolysis of alkenes; Optimierung der Probenahme von Hydroperoxiden und Untersuchungen zur Wasserdampfabhaengigkeit der Bildung von Hydroperoxiden bei der Ozonolyse von Alkenen

    Energy Technology Data Exchange (ETDEWEB)

    Becker, K.H.; Plagens, H.

    1997-06-01

    There are several sampling methods for hydroperoxides none of which is particularly reliable. The authors therefore tested three new methods in order to optimize hydroperoxide sampling and, using the optimized sampling procedure, to investigate the water vapour dependence of hydroperoxide formation during ozonolysis of alkenes. (orig.) [Deutsch] Fuer die Probenahme von Hydroperoxiden existieren verschiedene Verfahren, von denen bisher keines als besonders zuverlaessig angesehen werden konnte. Daher wurden in dieser Arbeit drei Verfahren getestet, um die Probenahme von Hydroperoxiden zu optimieren und mit dem entsprechenden Verfahren die Wasserdampfabhaengigkeit der Bildung von Hydroperoxiden bei der Ozonolyse von Alkenen zu untersuchen. (orig.)

  6. Entwicklung einer kontaktfreien nichtdestruktiven Methode zur Messung von mechanischen und elastischen Eigenschaften von mikromechanischen Mehrschichtsystemen mit akustischen Oberflächenwellen

    OpenAIRE

    Bennis, Abdelali

    2009-01-01

    Mit dieser Arbeit wird ein Beitrag zur Weiterentwicklung der akustischen lasermesstechnischen Verfahren zur Ermittlung von mechanischen und elastischen Eigenschaften von mikromechanischen Mehrschichtsystemen geleistet. Zu diesen Eigenschaften zählen das E-Modul, die Dichte, die Dicke sowie die Poissonzahl. Die meisten akustischen lasermesstechnischen Verfahren basieren auf der optischen Erzeugung von breitbandigen akustischen Wellen in einem Schichtsystem und der Ermittlung der Geschwindig...

  7. Die graphic des ersten buches von Prekmurje

    Directory of Open Access Journals (Sweden)

    Vilko Novak

    1978-12-01

    Full Text Available Das erste Buch, geschrieben im Dialekt von Prekmurje (Übermurgebiet in Slowenien, war die Übersetzung des Kleinen Katechismus von M.Luther, angefertigt von Ferenc Temlin: Mali katechismus … erschienen in Halle, 1715. Über den Übersetzer schrieben bisher ausführlicher M. Rupel und V. Novak, s. Anmerkung 3. Der Verfasser untersucht, wie sich Temlin in seiner Schreibweise an die ungarische Graphik anlehnte, wie vor ihm schon die handschriftlichen Gesangbücher in Prekmurje und die kaj-kroatischen Schriftsteller. Vokalen.- Temlin benutzt konsequent die akutierten a und e fur lange und enge Vokale, indem ihm das nichtakutierte ein nichtakzentuiertes oder kurzakzentuiertes, niedriger aber einen breeiinten, nichtakzentuier­ten oder kurzakzentuierten Vokal bedeutet. Den Reflex von jat  schreibt er konsequent als ei, die dem Dialekt bekannten ö aus dem engen, kurzen postlabialen oder postdentalen e oder ,ü, und ü aus dem ethymologischen u (nur einige Ausnahmen in Lehnwörtern schreibt er mit diesen Buchstaben. (Beispiele für diese und die nächsten Buchstaben und Laute in der Abhandlung. Das lange o, das in seiner Sprache als Diphtong ou  reflektiert, bezeichnet er auch als solches. Konsonanten.- Für einige davon verwendet Temlin ungarische Doppelzeichen, deren Alter und Entwicklung der Verfasser der Abhandlung angibt. Das c bezeichnet T.ständig als cz, das s als /z, nur in einigen Fällen als z. Den letzt angeführten Buchstaben benutzt er konsequent für z.- Komplizierter ist die Bezeichnung der Zischlaute: für č schreibt T. sehr haufig cf, aber noch häufiger mit cs, sehr selten dagegen ch - Dies scheint aus kirchlichen Ausdrücken, aus kaj-kroatischen Büchern entnommen bzw. Durch die Kirche erlernt.- Das š bezeichnet T. mit doch nicht selten auch mit Dieselben zwei Buchstaben dienen ihm auch für die Bezeichnung des Lautes ž. Bei den Labiallauten ist zu bemerken, dass T. für die Präposition vu manch­ mal schreibt, sonst

  8. Politische Bildung im Kontext von Regierung, Unterricht und Zucht

    Directory of Open Access Journals (Sweden)

    Thomas Rucker

    2014-02-01

    Full Text Available Johann Friedrich Herbart (1776-1841 gilt als der Begründer der wissenschaftlichen Pädagogik. In diesem Beitrag wird zu zeigen versucht, dass Herbart die Unterstützung politischer Bildung als eine Aufgabe von Regierung, Unterricht und Zucht bestimmt und in seinem Werk wichtige „Bausteine“ für eine Theorie der politischen Bildung unter den Bedingungen von Erziehung vorlegt hat. Nach Herbart ist das politische Selbst- und Weltverhältnis auf Sachverhalte bezogen, die nicht nur die Lebensführung einzelner Menschen, sondern die Lebensführung einer Mehrzahl von Menschen betreffen. Nicht das Zusammenleben von Menschen generell ist jedoch Orientierungsgesichtspunkt des politischen Selbst- und Weltverhältnisses, sondern nur das problematisch gewordene Zusammenleben. Politik ergibt sich nach Herbart aus einem Konflikt hinsichtlich der Frage, wie das Zusammenleben von Menschen geregelt sein sollte. Während die Regierung lediglich mittelbar einen Beitrag zur politischen Bildung leistet, indem sie die Voraussetzungen für Unterricht und Zucht bereitstellt, fungieren die beiden zuletzt genannten Formen von Erziehung als die eigentlichen Medien, in denen die politische Bildung im Sinne Herbarts ihren Ort hat.

  9. Étude concernant l’effet de mise à la terre dans le système de protection liaison au neutre

    Directory of Open Access Journals (Sweden)

    Jan Ignat

    2009-01-01

    Full Text Available La sécurité des consommateurs de l’énergie électrique fait partie des principales demandes de la Loi 10/95, concernant la qualité dans les bâtiments. Le risque d’un choc électrique doit être diminué en adoptant un système de protection basé sur un moyen de base et un ou plusieurs complémentaires. Dans cet article, on étudie l’effet de mise à la terre, comme moyen complémentaire de celui de base qui adopte la liaison au conducteur du neutre. Cette étude se justifie de plus par l’apparition des moyens basés sur la déconnection automatique qui peuvent être complémentaires à la mise à la terre.

  10. Elasticplastic discs under plane stress conditions

    CERN Document Server

    Alexandrov, Sergey

    2015-01-01

    This Volume presents a unified approach to calculate the plane stress distribution of stress and strain in thin elastic/plastic discs subject to various loading conditions. There is a vast amount of literature on analytical and semi-analytical solutions for such discs obeying Tresca’s yield criterion and its associated flow rule. On the other hand, most of analytical and semi-analytical solutions for Mises yield criterion are based on the deformation theory of plasticity. A distinguished feature of the solutions given in the present volume is that the flow theory of plasticity and Mises yield criterion are adopted. The solutions are semi-analytical in the sense that numerical methods are only necessary to evaluate ordinary integrals and solve transcendental equations. The book shows that under certain conditions solutions based on the deformation and flow theories of plasticity coincide. All the solutions are illustrated with numerical examples. The goal of the book is to provide the reader with a vision an...

  11. Design of recuperators; Nachrechnung von Rekuperatoren. Moeglichkeiten zur Loesung der inverse Aufgabe bei waermetechnischen Berechnungen von Rekuperatoren mit Metallrohren

    Energy Technology Data Exchange (ETDEWEB)

    Stanev, R. [Univ. fuer Chemische Technologie und Metallurgie, Sofia (Bulgaria). Lehrstuhl fuer Physikalische Metalurgie und Waermeanlagen

    2004-02-01

    Possibilities for solution of the inverse task by heat-technical calculation of recuperators with metal pipes. The utilization of the waste heat in recuperators permits a decrease the fuel consumption of industrial and especially of metallurgical furnaces up to 30%. In the paper is represented a possibility for calculation of recuperators, which is useable not only for this application, than also for the design of air-coolers and other heat-exchangers. (orig.) [German] Die Abgaswaermenutzung mittels Rekuperator erlaubt eine Senkung des Brennstoffverbrauchs von Industrieoefen und insbesondere von den metallurgischen Oefen um bis zu 30%. Im Beitrag wird eine Moeglichkeit der Berechnung von Rekuperatoren vorgestellt, die nicht nur fuer diese Anwendung, sondern auch fuer die Auslegung von Luftkuehlern und anderen Waermeuebertragern verwendet werden kann. (orig.)

  12. Bitcoins. Eine Analyse von Kryptowaehrungen und deren Anwendung von kontroversiellen Angeboten im Darknet bis hin zu traditionellem Onlinehandel.

    OpenAIRE

    Linzner, Manfred

    2016-01-01

    von Manfred Linzner Arbeit an der Bibliothek noch nicht eingelangt - Daten nicht geprueft - Link noch nicht aktiv Abweichender Titel nach Übersetzung der Verfasserin/des Verfassers Technische Universität Wien, Univ., Diplomarbeit, 2016

  13. Prophylaxis escalation in severe von Willebrand disease: A prospective study from the von Willebrand Disease Prophylaxis Network

    NARCIS (Netherlands)

    T.C. Abshire (Thomas Calvin); J. Cox-Gill; C.L. Kempton; F.W.G. Leebeek (Frank); M. Carcao (M.); P. Kouides (P.); S. Donfield (S.); E. Berntorp

    2015-01-01

    textabstractBackground: Treatment of mucosal bleeding (epistaxis, gastrointestinal bleeding, and menorrhagia) and joint bleeding remains problematic in clinically severe von Willebrand disease (VWD). Patients are often unresponsive to treatment (e.g. desmopressin or antifibrinolytic therapy) and may

  14. Optimized designs for 2D and 3D thermoelastic structures

    DEFF Research Database (Denmark)

    Pedersen, Pauli; Pedersen, Niels Leergaard

    2011-01-01

    . In compliance minimization it may be advantageous to decrease the total volume, but for strength maximization it is argued to keep the total permissible volume. For direct strength maximization the sensitivity analysis of local von Mises stresses is demanding. A simple recursive procedure to obtain uniform...... energy density (or uniform von Mises stress) is presented and applied, and it is shown by examples that the obtained designs are close to fulfilling also strength maximization. Explicit formulas for equivalent thermoelastic loads in 2D and 3D finite element analysis are derived and applied, including...

  15. He who is Unfit to Serve his Fellow Citizens Wants to Rule Them. The Political Dimensions of Mises' Theory of Bureaucracy

    OpenAIRE

    CARNIS, L

    2011-01-01

    An important literature exists on bureaucracy. It deals with economic and political consequences. Many scholars analysed these particular organizations and different schools of thought provided their own interpretation of bureaucratic phenomena. Mises' theory of bureaucracy is known as being an important contribution from the Austrian economics school. However, the political dimension of his works on bureaucracy is less known. This article proposes an analysis of such a dimension.

  16. Le rôle de la recherche dans la mise en œuvre de la Politique d'aide ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Le rôle de la recherche dans la mise en œuvre de la Politique d'aide internationale féministe du Canada. Arjan de Haan. 17 août 2017. Une femme ... Nous choisissons de nous concentrer sur l'autonomisation économique des femmes parce que notre analyse a démontré qu'à l'échelle mondiale, il y a eu moins de progrès ...

  17. Mise en pratique for the definition of the candela and associated derived units for photometric and radiometric quantities in the International System of Units (SI)

    Science.gov (United States)

    Zwinkels, Joanne; Sperling, Armin; Goodman, Teresa; Campos Acosta, Joaquin; Ohno, Yoshi; Rastello, Maria Luisa; Stock, Michael; Woolliams, Emma

    2016-06-01

    The purpose of this mise en pratique, prepared by the Consultative Committee for Photometry and Radiometry (CCPR) of the International Committee for Weights and Measures (CIPM) and formally adopted by the CIPM, is to provide guidance on how the candela and related units used in photometry and radiometry can be realized in practice. The scope of the mise en pratique recognizes the fact that the two fields of photometry and radiometry and their units are closely related through the current definition of the SI base unit for the photometric quantity, luminous intensity: the candela. The previous version of the mise en pratique was applied only to the candela whereas this updated version covers the realization of the candela and other related units used for photometric and radiometric quantities. Recent advances in the generation and manipulation of individual photons show great promise of producing radiant fluxes with a well-established number of photons. Thus, this mise en pratique also includes information on the practical realization of units for photometric and radiometric quantities using photon-number-based techniques. In the following, for units used for photometric and radiometric quantities, the shorter term, photometric and radiometric units, is generally used. Section 1 describes the definition of the candela which introduces a close relationship between photometric and radiometric units. Sections 2 and 3 describe the practical realization of radiometric and photon-number-based units, respectively. Section 4.1 explains how, in general, photometric units are derived from radiometric units. Sections 4.2-4.5 deal with the particular geometric conditions for the specific photometric units. Section 5 deals very briefly with the topic of determination of measurement uncertainties in photometry.

  18. Electronic Resource Management System. Vernetzung von Lizenzinformationen

    Directory of Open Access Journals (Sweden)

    Michaela Selbach

    2014-12-01

    Full Text Available In den letzten zehn Jahren spielen elektronische Ressourcen im Bereich der Erwerbung eine zunehmend wichtige Rolle: Eindeutig lässt sich hier ein Wandel in den Bibliotheken (fort vom reinen Printbestand zu immer größeren E-Only-Beständen feststellen. Die stetig wachsende Menge an E-Ressourcen und deren Heterogenität stellt Bibliotheken vor die Herausforderung, die E-Ressourcen effizient zu verwalten. Nicht nur Bibliotheken, sondern auch verhandlungsführende Institutionen von Konsortial- und Allianzlizenzen benötigen ein geeignetes Instrument zur Verwaltung von Lizenzinformationen, welches den komplexen Anforderungen moderner E-Ressourcen gerecht wird. Die Deutsche Forschungsgemeinschaft (DFG unterstützt ein Projekt des Hochschulbibliothekszentrums des Landes Nordrhein-Westfalen (hbz, der Universitätsbibliothek Freiburg, der Verbundzentrale des Gemeinsamen Bibliotheksverbundes (GBV und der Universitätsbibliothek Frankfurt, in dem ein bundesweit verfügbares Electronic Ressource Managementsystem (ERMS aufgebaut werden soll. Ein solches ERMS soll auf Basis einer zentralen Knowledge Base eine einheitliche Nutzung von Daten zur Lizenzverwaltung elektronischer Ressourcen auf lokaler, regionaler und nationaler Ebene ermöglichen. Statistische Auswertungen, Rechteverwaltung für alle angeschlossenen Bibliotheken, kooperative Datenpflege sowie ein über standardisierte Schnittstellen geführter Datenaustausch stehen bei der Erarbeitung der Anforderungen ebenso im Fokus wie die Entwicklung eines Daten- und Funktionsmodells. In the last few years the importance of electronic resources in library acquisitions has increased significantly. There has been a shift from mere print holdings to both e- and print combinations and even e-only subscriptions. This shift poses a double challenge for libraries: On the one hand they have to provide their e-resource collections to library users in an appealing way, on the other hand they have to manage these

  19. Jade aus Amerika und weitere Grünsteinobjekte von Alexander von Humboldt aus dem Berliner Mineralienkabinett

    OpenAIRE

    Renate Nöller

    2009-01-01

    Alexander von Humboldt schickte aus Amerika Mineralproben, die nicht nur von naturwissenschaftlichem oder wirtschaftlichem Interesse waren. Vor allem grünes Steinmaterial, sogenannte Jade, war in Mesoamerika kulturell sehr bedeutsam und weit verbreitet, so daß sich aus diesem Rohstoff in der Sammlung auch bearbeitete Stücke vorfinden. Sie erlangten in Europa unterschiedliche Aufmerksamkeit. Die Jadeaxt und die Sonnenscheibe - beide im zweiten Weltkrieg verloren gegangen, hatten als “Humboldt-...

  20. Entwicklung von Dünnschicht-Reaktionsröhrchen zur Bestimmung von Schwefelwasserstoff, Chlor und Tetrachlorethen in Luft

    OpenAIRE

    Schwierz, Torge

    2000-01-01

    Dünnschicht-Reaktionsröhrchen zeichnen sich gegenüber konventionellen Prüfröhrchen durch höhere analytische Leistungen (Nachweisvermögen, Reproduzierbarkeit, Empfindlichkeit, objektive Auswertung) aus, ohne die Vorteile der einfachen praktischen Handhabung bei gasspurenanalytischen Messungen aufzugeben. In der vorliegenden Arbeit wird die Entwicklung von Dünnschicht-Reaktionsröhrchen für die Analyten Schwefelwasserstoff, Chlor und Tetrachlorethen beschrieben. Zum Nachweis von Schwefelwasserst...

  1. Nouvelles techniques de mise en valeur des ressources d'hydrocarbures New Techniques for Valorising Hydrocarbon Resources

    Directory of Open Access Journals (Sweden)

    Boy De la Tour X.

    2006-11-01

    Full Text Available Après avoir montré l'importance des réserves de pétrole non conventionnel et l'enjeu que représente pour l'humanité la mise en exploitation de ces ressources, cette étude examine les axes actuels de recherches et l'état de la technologie pour chacune des sources de nouveau pétrole retenues : mers profondes, récupération assistée, huiles lourdes et sables asphaltiques, schistes bitumineux et conversion du charbon. Il en ressort que si les ressources de nouveau pétrole sont considérables, leur mise en valeur nécessitera des investissements très lourds, et le coût du pétrole ainsi produit restera élevé, comparé au coût actuel du pétrole conventionnel. Compte tenu des délais de mise en oeuvre, des problèmes technologiques restant à résoudre et de la nécessité de réaliser des pilotes semi-industriels très coûteux pour expérimenter les nouvelles techniques, il convient de consentir sans attendre un effort important de recherche technologique, impliquant un accroissement sensible des budgets de R&D, mais aussi des incitations financières appropriées. Cet effort de mise au point de technologies adaptées à ces sources d'hydrocarbures sera favorisé par les nouvelles conditions économiques créées par la rareté relative des réserves d'hydrocarbures classiques, à condition que les Etats, par leur politique, favorisent la production de ressources d'hydrocarbures à coût élevé. A l'heure actuelle, on peut évaluer la production de pétrole difficile à environ 100 Mt, l'essentiel étant réalisé dans le domaine des huiles lourdes et de la récupération assistée ; on estime que la production de nouveau pétrole pourrait représenter 200 à 350 Mt en 1990 et se situer entre 600 et 900 Mt en 2000, soit 5 à 8 % de la production de pétrole en 1990 et 15 à 20 % en 2000. Un tel objectif nécessiterait des investissements de l'ordre de 500 à 750 milliards de dollars 1980. After pointing out the importance of

  2. Inversion interpretation of the mise-a-la-masse data; Denryu den`i ho data no inversion kaiseki

    Energy Technology Data Exchange (ETDEWEB)

    Okuno, M.; Hatanaka, H.; Mizunaga, H.; Ushijima, K. [Kyushu University, Fukuoka (Japan). Faculty of Engineering

    1996-05-01

    A program was developed for the inversion interpretation of the mise-a-la-masse data, and was applied to a numerical model experiment and to the study of data obtained by actual probing. For the development of this program, a program was used that calculated by finite difference approximation the potential produced by a linear current source, and studies were made through forward interpretation, inversion interpretation of the acquired apparent resistivity data, comparison with the true solution, accuracy and tendency, and the limitations. In the simulation of a horizontal 2-layer model, the parametric value after 20 repetitions converged with deviation of 1% or lower. This program was applied to the data from probing the Hatchobara district, Oita Prefecture, using a model wherein the target area was divided into 5 from east to west, and into 2 in the direction of depth. The result suggested that there was a large-scale low-resistivity body deep in the ground in the southeastern part of the investigated area. Furthermore, there was a spot detected in the direction of east-northeast that suggested an electric structure continuous in the direction of depth and a fault-like structure discontinuous in the transverse direction. 7 refs., 9 figs.

  3. Isolation thermique et acoustique des bâtiments réglementation, produits, mise en oeuvre

    CERN Document Server

    Bureau Veritas

    2015-01-01

    Les impératifs d’efficacité énergétique et de confort acoustique dans les bâtiments entraînent de nouvelles réponses constructives et une évolution considérable des matériaux et procédés d’isolation. Tenant compte des derniers DTU parus, ce guide regroupe dans un même volume l’essentiel des dispositions techniques de mise en oeuvre des systèmes d’isolation thermique et phonique des bâtiments. Ainsi cet ouvrage : • apporte l’éclairage nécessaire à la compréhension des réglementations thermique et acoustique ; • définit les exigences à atteindre concernant l’isolement aux bruits aériens intérieurs et extérieurs, les niveaux de bruits de chocs et d’équipements, ainsi que le traitement acoustique des parties communes ; • détaille les techniques d’isolation des toitures étanchées et des couvertures ; • décrit l’isolation thermique des murs par l’intérieur et par l’extérieur. Ce manuel pratique est destiné aux maîtres d’ouvrage et promoteurs qui y tr...

  4. Die Rolle von Aldosteron im Knochenstoffwechsel

    Directory of Open Access Journals (Sweden)

    Tomaschitz A

    2012-01-01

    Full Text Available Das Steroidhormon Aldosteron wird in der Zona glomerulosa (ZG der Nebennierenrinde produziert. Kalzium spielt als gemeinsamer „Second Messenger“ eine zentrale Rolle in der durch Angiotensin II, ACTH und Kalium regulierten Aldosteronsynthese. Zahlreiche Studien der vergangenen Jahre dokumentierten die bedeutende Rolle des Aldosterons in der Pathogenese kardiovaskulärer Erkrankungen. Effekte von Aldosteron auf den Knochenstoffwechsel wurden bisher kaum untersucht. In humanen fetalen und adulten Knochenzellen wurde jedoch eine ausgeprägte Expression des Mineralokortikoidrezeptors (MR detektiert. In experimentellen Tierstudien wurden sowohl eine spezifische Aldosteron-MR-Interaktion im Knochengewebe als auch die osteoprotektive Wirkung der MR-Blockade mit Spironolakton beobachtet. Aldosteron kann durch die Hemmung der alkalischen Phosphatase indirekt eine gesteigerte Osteoblastenproliferation induzieren. Die wechselseitige Beeinflussung von Aldosteron und Parathormon (PTH könnte eine bedeutende Rolle in der Pathophysiologie kardiovaskulärer Erkrankungen und des Knochenstoffwechsels spielen. PTH kann sowohl über die Aktivierung spannungsabhängiger Kalziumkanäle als auch durch Bindung an den PTH/PTH-rP-Rezeptor der Zona-glomerulosa- Zellen eine Stimulation der Aldosteronsynthese induzieren. Dies bestätigt sich mit einem signifikanten Rückgang der Plasmaaldosteronkonzentration nach einer Parathyreoidektomie bei Patienten mit einem primären Hyperparathyreoidismus. In Tiermodellen der Herzinsuffizienz führt der relative Aldosteronüberschuss über eine verstärkte renale Kalziumexkretion zu einem sekundären Hyperparathyreoidismus, der durch die gesteigerte Kalziummobilisation aus dem Knochengewebe zu einem erhöhten Frakturrisiko in dieser Patientengruppe beiträgt. Der im Rahmen des primären Hyperaldosteronismus beobachtete sekundäre Hyperparathyreoidismus kann durch eine Hemmung der Aldosteronwirkung/Aldosteronsynthese supprimiert

  5. Von Roll RCP method - first experiences; Von Roll RCP - Verfahren. Erste Erfahrungen

    Energy Technology Data Exchange (ETDEWEB)

    Capitaine, P.; Engweiler, J. [Roll Umwelttechnik AG, Zuerich (Switzerland)

    1998-09-01

    The RCP method was designed as a residue-optimised alternative to the thermally optimised grate firing of residual wastes. Its technical realisation and development to market maturity took no more than 5 years. In the first process stage the waste is converted to high-carbon pyrolysis charcoal and high-rank gas in the absence of oxygen. In the second stage these substances are oxidised by addition of oxygen. The resulting temperature causes the non-combustible constituents of the slag to melt. In a third, optional, stage this molten slag can be liberated of (heavy) metals to such an extent that it can subsequently be used directly as additive for grinding. Further exhaust gas treatment is facilitated by the use of a circulatory fluidised-bed secondary combustion chamber. Despite the reduced flue gas volume and resultant higher pollutant concentrations in the crude gas, overall emissions are lower than in conventional plants. [Deutsch] Das reststoffoptimierte RCP Verfahren ist als Alternative zur thermisch optimierten Rostverbrennung von Restabfaellen konzipiert. In nur fuenf Jahren wurde das Verfahren technisch umgesetzt und zur Marktreife entwickelt. In einer ersten Stufe des Verfahrens wird der Abfall unter Luftabschluss in einen kohlenstoffreichen Pyrolysekoks und eine heizwertreiches Gas umgesetzt. Im zweiten Schritt werden diese Stoffe unter Zugabe von Sauerstoff oxidiert. Dabei treten Temperaturen auf, bei denen die nichtbrennbaren Bestandteile der Schlacke schmelzen. Optional wird diese Schmelzschlacke in einem dritten Schritt derart von (Schwer-) Metallen befreit, dass sie anschliessend direkt als Zement-Zumahlstoff eingesetzt werden kann. Die Nutzung der zirkulierenden Wirbelschicht - Nachbrennkammer zur Abgasbehandlung vereinfacht die weitergehende Abgasbehandlung. Trotz verringertem Rauchgasvolumen und damit hoeheren Schadstoffkonzentrationen im Rohgas werden die Gesamtemissionen gegenueber konventionellen Anlagen verringert. (orig./SR)

  6. The Mechanical Behavior of Poly(Methyl Methacrylate) Under Pressure

    Science.gov (United States)

    1975-02-03

    dependency of the shear band initiation stress 46 and fairly well that of yield stress. Starita and Keaton proposed, similarly, an internal...might be found 47 48 4fi in the ideas of Goldstein ’ and Starita and Keaton . Combination of the non-linear pressure dependent von Mises

  7. Entstehungsbedingungen von Übergängen von der Schule in den Beruf aus qualitativer und quantitativer Perspektive

    Directory of Open Access Journals (Sweden)

    Nora Gaupp

    2013-03-01

    Full Text Available Methodenintegration wird in den Sozialwissenschaften mit dem Argument sich ergänzender Erkenntnismöglichkeiten häufig gefordert. Die vorliegende Analyse zu Übergangswegen von der Schule in Ausbildung und Arbeit von Jugendlichen mit Hauptschulbildung beruht auf Daten einer quantitativen Panelstudie und einer qualitativen Ergänzungsstudie. Aus quantitativer und qualitativer Perspektive wird jeweils ein Einzelfall betrachtet sowie im Rahmen einer Modellbildung eine Verallgemeinerung auf Aggregatebene vorgenommen. Über ein logistisches Regressionsmodell wird die Bedeutung von zentralen individuellen, sozialen und strukturellen Merkmalen wie Schulleistungen, beruflichen Plänen, individuellen Problembelastungen, Migrationshintergrund und Arbeitslosigkeit der Eltern sowie regionaler Arbeitsmarktsituation für den Verlauf von Übergangswegen (Direkteinstieg in Ausbildung, Umweg in Ausbildung über schulische oder berufsvorbereitende Zwischenschritte, fortgesetzter mehrjähriger Schulbesuch und prekäre Wege in Ausbildungslosigkeit untersucht. Über das qualitative Paradigma konnten vier für den Verlauf von Übergängen zentrale Dimensionen identifiziert werden: Agency, Motivation, kritische biografische Ereignisse und soziale Interaktionen. Der Schritt der Modellbildung integriert die vier Erfahrungsebenen und zeigt ihre Bedeutung für Übergänge von der Schule in den Beruf. Die Diskussion fragt nach Möglichkeiten und Grenzen der Erkenntnisentwicklung der beiden Forschungszugänge. URN: http://nbn-resolving.de/urn:nbn:de:0114-fqs1302126

  8. Einfluss von verschiedenen Erodierstrukturen auf den Reibwert von Kunststoff-Kunststoff Paarungen

    OpenAIRE

    Bergmann, André

    2016-01-01

    Im Beitrag werden bei verschiedenen Lastkollektiven und zwei Reibgeschwindigkeiten die Erodierstrukturen K27, K36, K42 und die Ätzstruktur K36 mit glatten Probekörpern hinsichtlich des Reibwertes und des Verschleißverhaltens untersucht. Als strukturierte Probekörper kommen die Kunststoffe POM und PA und als Gegenkörper zwei verschiedene PE-UHMW´s zum Einsatz. Die Ergebnisse zeigen eine deutliche Abhängigkeit des Reibwertes von der Oberflächenstruktur der Probekörper, jedoch ist die Senkun...

  9. "Die Toten reiten schnelle." Literarische Zitate in Briefen von und an Alexander von Humboldt

    Directory of Open Access Journals (Sweden)

    Ingo Schwarz

    2007-04-01

    Full Text Available Article in GermanAbstract in English and GermanAlexander von Humboldt and his correspondents liked to enrich or embellish their letters with quotations from classic works of ancient literature as well as from recent poems, plays, or novels. This paper tries to show that references to literature were very often used in order to express thoughts and feelings more clearly not so much for impressing the recipients of letters with high education. In educated circles a good knowledge of ancient and modern works of literature was a standard requirement, which often allowed the letter writers to use quotations in a playful manner.

  10. Entwurf und Simulation von Makromodellen zur transienten Simulation von thermo-elektrischen Kopplungen in einem Netzwerksimulator

    OpenAIRE

    Schacht, Ralph Karl Benjamin

    2002-01-01

    In der vorliegenden Arbeit wird eine Methode vorgestellt, welche die Beschreibung und Si-mulation von thermo-elektrischen Kopplungen während des Design-Prozesses mittels Mak-romodellierung unterstützt. Das Makromodell ist für den Einsatz in dem Schaltungssimulator PSpice zugeschnitten. Es ermöglicht die rechenzeiteffiziente transiente Simulation zwischen thermo-elektrisch gekoppelten Komponenten eines komplexen Mikrosystems. Im Rahmen dieser Arbeit wurde zunächst eine für die Problemstellung ...

  11. Zur Struktur und Funktion von Synonymen

    Directory of Open Access Journals (Sweden)

    Marina Zorman

    1998-12-01

    Full Text Available Der Artikel behandelt die Synonyme im Licht der funktionell-strukturellen Sprachtheorie Coserius. 1 Die Wahl der theoretischen Grundsätze wurde durch die Festellung diktiert, daß die bisherigen Erkenntnisse über die Synonymie widersprüchlich sind und daß auch schon über alle Feststellungen berechtigte Einsprüche erhoben wurden. Deshalb wird in dieser Arbeit auf der genannten theoretischen Grundlage, die verschiedene Gesichtspunkte des Problems verbindet, anstatt sie zu trennen (s. Punkt 2, ein Modell für die Analyse von Synonymen vorgestellt (3, das die klassischen Schwächen der Semantikforschung (zu geringe Menge tatsächlicher Daten, Subjektivität und Introspektion durch eine empirische Untersuchung in einem Textkorpus zu ersetzen versucht. In die Analyse sind drei Inhaltsebenen einbezogen (Bezeichnung, Bedeutung und Sinn und ihnen sind jeweils entsprechende Untersuchungsmethoden zugeordnet. Im Sinne des Modells wurden in der Arbeit Zorman 1997 zwei slowenische Synonympaare (kuverta - ovojnica und borba - boj analysiert, die als Beispiele reiner (und totaler Synonymie gelten können. Die Analyse wird aus Platzgründen an dieser Stelle nicht detailliert dargestellt,2 veranschaulicht werden nur ihre Tragweite und die Ergebnisse (4. Im letzten Teil (5 werden die Leistungen der vorgeschlagenen Methode bewertet und einige Annahmen dargestellt, die der weiteren Erforschung der Synonyme dienen könnten. Die objektive Behandlung der Synonymie unter unterschiedlichen Gesichtspunkten scheint einige Dogmen über Synonyme in Frage zu  stellen.

  12. In situ measurement of flow characteristics of natural saline rock in loose zones for gas and saline solutions in given rock stress conditions. Final report; In-situ-Ermittlung von Stroemungskennwerten natuerlicher Salzgesteine in Auflockerungszonen gegenueber Gas und Salzloesungen unter den gegebenen Spannungsbedingungen im Gebirge. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Haefner, F.; Belohlavek, K.U.; Behr, A.; Foerster, S.; Pohl, A.

    2001-04-01

    A method and equipment were developed for measuring the extension of loose zones around worked areas in saline rock and for in situ measurement of very small permeabilities and porosities in these zones. The experiments are based on unsteady borehole logs with flowing gases or liquids with special multiple pack systems that enable measurements from 4 cm to 15 m from the cavern contour. The measurements were evaluated by a specially developed software with automatic parameter identification. Permeabilities were identified between 10{sup 14} m{sup 2} and the detection limit of 10{sup 24} m{sup 2} and effective porosities of less than 0.1% at experimental times of several minutes up to several days. The logs were made in 3 mines in Stassfurt rock salt at depths of 700 and 500 m with different geological and geomechanical boundary conditions, worked in different ways and for different periods of time (between a few days and 37 years). Some of the findings were validated by ultrasonic measurements. [German] Fuer die Ermittlung der Ausdehnung von Auflockerungszonen um bergmaennisch aufgefahrene Strecken/Hohlraeume im Salzgestein und zur In-situ-Bestimmung kleinster Permeabilitaeten und Porositaeten in diesen Bereichen wurde ein Verfahren und eine praktikable Versuchsausruestung entwickelt. Diese eignet sich auch fuer Frac-Untersuchungen. Basis der Versuchsdurchfuehrungen sind instationaere Bohrlochuntersuchungen mit Gasen oder Fluessigkeiten als Stroemungsfluid unter Einsatz spezieller Mehrfachpackersysteme. Damit sind Messungen ab 4 cm Abstand zur Hohlraumkontur bis zu 15 m moeglich. Die Versuchsauswertung erfolgt mittels einer speziell entwickelten Software mit automatischer Parameteridentifikation, die die instationaere Stroemung um die Versuchsbohrung raeumlich vollstaendig beschreibt. Permeabilitaeten wurden je nach Abstand zur Hohlraumkontur zwischen 10{sup -14} m{sup 2} und der Nachweisgrenze 10{sup -24} m{sup 2} und effektive Porositaeten bis <0,1% ermittelt, bei

  13. Bearbeitung von Forschungsfragen zur wissenschaftlichen Qualifizierung von Studierenden - ein Lehr- und Lernkonzept für das Blockpraktikum Allgemeinmedizin [Students' performing of practical research tasks for their scientific qualification - an approach within the family practice internship in undergraduate education

    Directory of Open Access Journals (Sweden)

    Moßhammer, Dirk

    2011-05-01

    Full Text Available [english] Background: Future physicians should be educated in evidence-based medicine. So it is of growing importance for medical students to acquire both practical medical and basic research competencies. However, possibilities and concepts focusing on the acquisition of basic practical research competencies during undergraduate medical studies in Germany are rare. Therefore the aim of this article is to develop a didactic and methodological concept for research-based teaching and learning based on the initial results from the block placement in general practice.Methods: Connecting medical didactic approaches with classic educational control measures (knowledge, acceptance and transfer evaluation, process evaluation, and outcome evaluation.Results: We describe the steps for implementing a research task into the block placement in general practice. Also stressed is the need to develop didactic material and the introduction of structural changes. Furthermore, these steps are integrated with the individual educational control measures. A summary serves to illustrate the learning and teaching concept (Block Placement Plus.Conclusion: The conceptualisation of the Block Placement Plus leads to changes in the daily life routine of medical education during the undergraduate block placement in general practice. The concept can in principle be transferred to other courses. It may serve as an instrument for teachers within the framework of a longitudinal curriculum for the scientific qualification of medical students.[german] Hintergrund: Zukünftige Ärzte sollen zu Evidenz-basierter Medizin (EbM ausgebildet werden. Deswegen ist neben der Ausbildung von medizinischen Kompetenzen auch zunehmend eine wissenschaftliche Basisausbildung wichtig. Möglichkeiten und Konzepte, die auf die Entwicklung von Forschungskompetenzen und wissenschaftlicher Qualifizierung von Studierenden abzielen, sind jedoch bisher spärlich. Ziel des vorliegenden Artikels ist es, aus

  14. Polymorphism in the promoter region of von Willebrand factor gene and von Willebrand disease type 1

    Directory of Open Access Journals (Sweden)

    Daniel Simon

    2003-12-01

    Full Text Available The -1185A/G polymorphism in the 5'-regulatory region of the von Willebrand factor (VWF gene was associated with VWF plasma levels in a normal population. This study was undertaken to evaluate whether there is a relationship between this polymorphism and type 1 von Willebrand disease (VWD, a disorder characterized by a quantitative deficiency of VWF. The association between this polymorphism and plasma VWF levels in normal Brazilian individuals was also analyzed. Control subjects (n = 460 and type 1 VWD patients (n = 41 were studied. Polymerase chain reaction (PCR amplification of the 864-bp VWF promoter region followed by AccII restriction-digestion was used to identify the -1185A/G genotypes. The -1185G allele frequency was 57% in normal individuals and 63% in type 1 VWD patients, this difference was not significant (p = 0.29. No significant association was observed between -1185A/G genotypes and VWF plasma levels in normal individuals, although VWF levels were in the same direction as those reported by another study, with subjects carrying the G allele having the lower levels. These results suggest that -1185A/G polymorphism is not associated with the partial deficiency of VWF in type 1 VWD patients.

  15. Nonlocal modeling and buckling features of cracked nanobeams with von Karman nonlinearity

    Science.gov (United States)

    Akbarzadeh Khorshidi, Majid; Shaat, Mohamed; Abdelkefi, Abdessattar; Shariati, Mahmoud

    2017-01-01

    Buckling and postbuckling behaviors of cracked nanobeams made of single-crystalline nanomaterials are investigated. The nonlocal elasticity theory is used to model the nonlocal interatomic effects on the beam's performance accounting for the beam's axial stretching via von Karman nonlinear theory. The crack is then represented as torsional spring where the crack severity factor is derived accounting for the nonlocal features of the beam. By converting the beam into an equivalent infinite long plate with an edge crack subjected to a tensile stress at the far field, the crack energy release rate, intensity factor, and severity factor are derived according to the nonlocal elasticity theory. An analytical solution for the buckling and the postbuckling responses of cracked nonlocal nanobeams accounting for the beam axial stretching according to von Karman nonlinear theory of kinematics is derived. The impacts of the nonlocal parameter on the critical buckling loads and the static nonlinear postbuckling responses of cracked nonlocal nanobeams are studied. The results indicate that the buckling and postbuckling behaviors of cracked nanobeams are strongly affected by the crack location, crack depth, nonlocal parameter, and length-to-thickness ratio.

  16. Entwicklungsperspektiven von Social Software und dem Web 2.0

    Science.gov (United States)

    Raabe, Alexander

    Der Artikel beschäftigt sich zunächst mit dem derzeitigen und zukünftigen Einsatz von Social Software in Unternehmen. Nach dem großen Erfolg von Social Software im Web beginnen viele Unternehmen eigene Social Software-Initiativen zu entwickeln. Der Artikel zeigt die derzeit wahrgenommenen Einsatzmöglichkeiten von Social Software im Unternehmen auf, erörtert Erfolgsfaktoren für die Einführung und präsentiert mögliche Wege für die Zukunft. Nach der Diskussion des Spezialfalles Social Software in Unternehmen werden anschließend die globalen Trends und Zukunftsperspektiven des Web 2.0 in ihren technischen, wirtschaftlichen und sozialen Dimensionen dargestellt. Wie aus den besprochenen Haupttrends hervorgeht, wird die Masse an digital im Web verfügbaren Informationen stetig weiterwachsen. So stellt sich die Frage, wie es in Zukunft möglich sein wird, die Qualität der Informationssuche und der Wissensgenerierung zu verbessern. Mit dem Einsatz von semantischen Technologien im Web wird hier eine revolutionäre Möglichkeit geboten, Informationen zu filtern und intelligente, gewissermaßen verstehende" Anwendungen zu entwerfen. Auf dem Weg zu einem intelligenten Web werden sich das Semantic Web und Social Software annähern: Anwendungen wie Semantic Wikis, Semantic Weblogs, lightweight Semantic Web-Sprachen wie Microformats oder auch kommerzielle Angebote wie Freebase von Metaweb werden die ersten Vorzeichen einer dritten Generation des Webs sein.

  17. Acquired von Willebrand syndrome: A rare disorder of heterogeneous etiology

    Directory of Open Access Journals (Sweden)

    P Kasatkar

    2013-01-01

    Full Text Available Context: Acquired von Willebrand syndrome (AVWS is a rare bleeding disorder that mimics the inherited form of von Willebrand disease (VWD in terms of laboratory findings and clinical presentation. Aims: To study the etiology of acquired VWD. Settings and Design: The patients referred from various hospitals in and out of Mumbai were included in the study. Materials and Methods: Six patients with AVWS diagnosed at this center over the last 10 years were analyzed against 171 patients with inherited VWD. The differential diagnosis of AVWS was made based on reduced levels of von Willebrand antigen and von Willebrand ristocetin cofactor, decrease in ristocetin induced platelet aggregation, absence of correction in mixing studies with no prior history of bleeding problems and a negative family history for bleeding disorders. Results: In three patients, the disease was associated with systematic lupus erythematosus, out of which one was also associated with Kikuchi lymphadenitis and second with autoimmune hemolytic anemia. Fourth case was associated with hypothyroidism and fifth was a case of dermatitis and vitiligo. The last patient was a case of hemophilia A with Burkitts lymphoma, who developed autoantibodies to von Willebrand factor. Except two patients, all other patients responded to immune suppressive therapy with corticosteroids, while the patient with hypothyroidism responded to oral thyroxine. Conclusion: AVWS is a rare condition and may often be missed or diagnosed as inherited disease associated with heterogeneous disease conditions.

  18. Choroba von Willebranda – najczęstsza osoczowa skaza krwotoczna

    Directory of Open Access Journals (Sweden)

    Bożena Sokołowska

    2010-08-01

    Full Text Available Von Willebrand disease is the most common hereditary haemorrhagic disorder. A majority of patients (70%have classic mild or moderate (type I von Willebrand disease, and women are mostly affected. Clinical manifestationsinclude menorrhagia and post partum bleeding.

  19. Groves-Schemata zur Lösung von Anreizproblemen bei der Budgetierung

    OpenAIRE

    Locarek, Hermann

    1992-01-01

    Groves-Schemata zur Lösung von Anreizproblemen bei der Budgetierung / von Günter Bamberg u. Hermann Locarek. - In: Controlling / Klaus Spremann ... (Hrsg.). - Wiesbaden : Gabler, 1992. - S. 657-670. - Auch ersch. als: Arbeitspapiere zur mathematischen Wirtschaftsforschung ; 110

  20. Stressprävention im Jugendalter: Die Leistungsgesellschaft fordert immer mehr von Jugendlichen - Erklärungsansätze von Stressentstehung und Bewältigung sowie Handlungsfelder der Sozialen Arbeit im Bereich Stressprävention im Jugendalter

    OpenAIRE

    Stuber, Daniela; Brunner, Céline

    2014-01-01

    Die vorliegende Arbeit befasst sich mit dem Thema Stressprävention im Jugendalter. Die Autorinnen gehen den Fragen nach, wie Stress während dieser Lebensphase entsteht und wie konstruktiv damit umgegangen werden kann. Anhand dieses Wissens leiten sie mögliche Handlungsfelder und präventive Handlungsempfehlungen für die Soziale Arbeit ab. Als fachliche Grundlage dient hierzu die Präventionstheorie von Martin Hafen. Während der Adoleszenz sind junge Menschen gemäss Steinemann (2005) durch entwi...

  1. Proof of pipeline strength based on measurements of inspection pigs; Festigkeitsnachweis von Pipelines aufgrund der Messergebnisse von Pruefmolchen

    Energy Technology Data Exchange (ETDEWEB)

    De la Camp, H.J.; Feser, G.; Hofmann, A.; Wolf, B.; Schmidt, H. [TUeV Sueddeutschland Bau und Betrieb GmbH, Muenchen (Germany); Herforth, H.E.; Juengling, K.H.; Schmidt, W. [TUeV Anlagentechnik GmbH, Berlin-Schoeneberg (Germany). Unternehmensgruppe TUeV Rheinland/Berlin-Brandenburg

    2002-01-01

    The report is aimed at collecting and documenting the state of the art and the extensive know how of experts and pipeline operators with regard to judging the structural integrity of pipelines. In order to assess the actual mechanical strength of pipelines based on measurement results obtained by inspection pigs, guidance is given for future processing, which eventually can be used as a basis for an industry standard. A literature study of the commercially available types of inspection pigs describes and synoptically lists the respective pros and cons. In essence the report comprises besides check lists of operating data for the pipeline and the pig runs mainly the evaluation of defects and respective calculating procedures. Included are recommendations regarding maintenance planning, verification of defects as well as repetition of pig runs. (orig.) [German] Ziel des Berichtes ist die Erfassung und Dokumentation zum derzeitigen Stand der Technik und des vorhandenen umfangreichen Know-how von Sachverstaendigen und Pipelinebetreibern auf dem Gebiet der sicherheitstechnischen Beurteilung von Pipelines. Fuer den Festigkeitsnachweis von Pipelines aufgrund der Messergebnisse von Pruefmolchen wurde ein Leitfaden als Basis fuer die zukuenftige Vorgehensweise erstellt, der eventuell die Grundlage eines normativen Regelwerkes bilden kann. In einer Literaturstudie wurden die auf dem Markt befindlichen Pruefmolchtypen zusammenfassend beschrieben und ihre Vor- und Nachteile tabellarisch gegenuebergestellt und bewertet. Neben der Erstellung von Checklisten fuer notwendige Daten zum Betrieb der Pipeline und der Molchlaeufe bildet die Fehlerbewertung mit entsprechenden Berechnungsverfahren den Hauptteil dieses Berichtes. Hinweise zur Instandhaltungsplanung (Fehlerverifikation und Molchlaufwiederholung) werden gegeben. (orig.)

  2. "Face to Interface": Zum Problem der Vertrauenskonstitution im Internet am Beispiel von elektronischen Auktionen

    OpenAIRE

    Brinkmann, Ulrich; Seifert, Matthias

    2001-01-01

    Am Beispiel von Internetauktionen geht der Beitrag der Frage nach, welche Rolle Vertrauen bei e-Commerce-Transaktionen spielt und über welche Institutionalisierungsprozesse Vertrauen befördert werden kann. Dazu wird zunächst mit Rückgriff auf den Stand der Forschung ein multidimensionales Verständnis von Vertrauen entwickelt. Anschließend wird die Spezifik von Internetauktionen als Sonderfall von e-Commerce aus der Perspektive der Vertrauensproblematik beleuchtet: beiden Transaktionsparteien ...

  3. Diurnal variation of von Willebrand factor in plasma

    DEFF Research Database (Denmark)

    Timm, Annette; Fahrenkrug, Jan; Jørgensen, Henrik L

    2014-01-01

    BACKGROUND: Quantitation of von Willebrand factor (VWF) in plasma is a central element in assessing von Willebrand disease (VWD). VWF activity is known to vary, which has partly been ascribed to biological and preanalytical variation. However, a possible diurnal expression of VWF has not been...... of light and 9 h of darkness); the plasma concentration of melatonin was used as an internal control to confirm the normal 24-h rhythms of the individual participants. RESULTS: The data, analyzed by rhythmometric statistics, revealed a significant variation (P = 0.02) and total amplitude of 22.6% in VWF...... and VWF and (ii) VWF propeptide and VWF was determined. Taken together, the data suggest changes in release and not in clearance. CONCLUSIONS: Diurnal variation in von Willebrand antigen and activity in plasma represents an important aspect of the biological variation. Standardized time-of-day plasma...

  4. Analyse von Videodokumentationen in der kunstpädagogischen Forschung

    Directory of Open Access Journals (Sweden)

    Anja Mohr

    2001-03-01

    Full Text Available Am Institut für Kunstpädagogik der Justus-Liebig-Universität werden seit 1996 unter der Leitung von Prof. Dr. A. von Criegern Untersuchungen zum kindlichen Bildverhalten am Computer durchgeführt. Aus ersten explorativen Studien ist inzwischen ein Forschungsprojekt entstanden, das auf breiterer theoretisch und empirischer Basis das bildnerische Verhalten von Vor- und frühen Grundschulkindern am Computer untersucht. Entgegen der bisher ergebnisorientierten, eher quantitativ arbeitenden Kinderzeichnungsforschung, stellte das Giessener Team sehr schnell fest, dass der gesamte Malprozess und mehr noch das gesamte ästhetische Verhalten am Computer mit qualitativen Methoden erforscht werden muss. Um diesem Anspruch gerecht zu werden, wurden die Beobachtungs-, Aufzeichnungs- und Analyseverfahren schrittweise optimiert und angepasst. Der Beitrag stellt die Bedeutung der im Projekt angewendeten Form der Videodokumentation für die Erforschung der digitalen Kinderzeichnung dar.

  5. Die Welt der Metadaten im Universum von Repositorien

    Directory of Open Access Journals (Sweden)

    Susanne Blumesberger

    2016-02-01

    Full Text Available Im Rahmen des österreichweiten Projekts „e-Infrastructures Austria“ wird derzeit im Cluster I „Metadatenkomplex aus technischer und nichttechnischer Sicht“ ein Wissensnetzwerk und eine Wissensplattform über Metadaten aufgebaut. Ziel ist die Vorbereitung von Guidelines wie man sowohl im IT-Bereich als auch in Bibliotheken im Bereich von Aufbau und Betrieb eines Repositoriums mit unterschiedlichen Fragen bzgl. Metadaten umgehen kann und soll. Neben Übersichten über die Umsetzungsmöglichkeiten von Linked (Open Data, Metadatenstandards, Best-Practicemodellen, neuen technischen Entwicklungen z. B. im Bereich Controlled Vocabularies, einer Bedarfserhebung von ForscherInnen zum Thema Metadaten für Forschungsdaten und einer Reihe an Use Cases wird auch eine Studie über den derzeitigen Stand der Dinge beim Umgang mit Metadaten an österreichischen Institutionen vorbereitet. Auch die Frage, wie Metadaten möglichst barrierefrei gestaltet sein können, bzw. wie Metadaten dazu beitragen können, dass Objekte für möglichst alle Menschen frei zugänglich sind, wird zentral behandelt. All diese Expertisen, die zu einer Umsetzung von Open Science führen sollen, fließen in die tägliche Praxis ein, zum Beispiel in die Gestaltung von Datamanagementplänen. 2016 wird an der Universität Wien eine Veranstaltung stattfinden, die zur Bewusstseinsbildung für die Wichtigkeit qualitätsvoller Metadaten beitragen soll. ExpertInnen sind dabei eingeladen, miteinander zu diskutieren und Erfahrungen auszutauschen. Es ist geplant, die Ergebnisse, die im Rahmen dieses Clusters entstehen, Open Access zu publizieren.

  6. Contribution to increase coach safety; Die Sicherheit von Omnibussen

    Energy Technology Data Exchange (ETDEWEB)

    Grandel, J.; Mueller, C.F.

    1996-09-01

    The risk of injuries for coach passengers is comparatively low. Nevertheless some periodical occurring serious accidents cause discussions about the coach safety. To objectivize this discussion and to find measures to increase coach safety the Dekra accident research team has started to analyse the real accident events. The basic instrument for this work is the Dekra accident database. The analysis of about 200 real coach accidents shows that single accidents and rollover accidents cause a high risk of serious injuries for the coach occupants. The ejection of unbelted passengers and the collapse of the roof structure are often cause of death and severe injury. To get more detailed information about the kinematic processes during the impact it was necessary to design crash tests based on the results of the real accident investigations. To realize these crash tests Dekra used its own crash centre in Neumuenster. The present study shoes that an integral passenger safety-system consisting of seat, restraint system and body structure is able to increase coach safety. The effectiveness of this system assumes an optimised interacting between every part of the system. (orig.) [Deutsch] Einzelne schwere Busunfaelle sorgen immer wieder fuer negative Schlagzeilen und fuehren zu Diskussionen ueber die Sicherheit von Omnibussen. Fehlendes Grundlagenwissen fuehrt dabei haeufig zu falschen Schlussfolgerungen. Wichtigste Basis fuer eine sachliche Diskussion und die Ableitung von Verbesserungsmassnahmen bildet eine sorgfaeltige und tiefgehende Analyse der realen Omnibusunfaelle. Das Defizit in der grundlegenden Erforschung von Busunfaellen wurde durch eine umfassende Unfallanalyse der Dekra-Unfallforschung beseitigt. Aus dem Realunfallgeschehen abgeleitete und im Dekra-Crash-Zentrum durchgefuehrte Versuche vervollstaendigen das Gesamtbild und geben detaillierte Erkenntnisse bezueglich der Kinematik von Omnibus und Businsassen. Ausgehend von einem bereits hohen Sicherheitsniveau

  7. Der Beitrag von Schreib Peer Tutor_innen zur nachhaltigen Entwicklung von Schreibzentren. Eine empirische Untersuchung auf der Grundlage von Expert_inneninterviews mit Peer Tutor_innen aus deutschen Schreibzentren.

    OpenAIRE

    Poloubotko, Anja

    2014-01-01

    Die vorliegende Arbeit trägt zur Erweiterung der Schreibzentrumstheorie bei, indem die Perspektiven von Peer Tutor_innen auf ihre Rolle im Schreibzentrum und deren Beitrag zur Entwicklung von Schreibzentren beleuchtet werden. Inspiriert durch das Peer Writing Tutor Alumni Research Project (Hughes et al. 2010) und die Erkenntnis von Katrin Girgensohn, dass Peer Tutor_innen eine Schlüsselrolle innerhalb der Schreibzentrumsentwicklung wahrnehmen, sollen im Rahmen der Arbeit folgende Fragen beant...

  8. Die grossen Physiker und ihre Entdeckungen von den fallenden Körpern zu den Quarks

    CERN Document Server

    Segrè, Emilio

    1998-01-01

    Von Galileo Galilei bis zu Richard Feynman und Murray Gell-Mann - von den fallenden Körpern zu den Quarks: Der Physiknobelpreisträger Emilio Segre hat seine ganz persönliche Geschichte der Physik geschrieben. Er erzählt von den großen Gestalten und deren wichtigen Entdeckungen mit großer Anschaulichkeit und Lebendigkeit.

  9. Muuga / Mary von Grünewaldt ; tõlk. Mati Sirkel

    Index Scriptorium Estoniae

    Grünewaldt, Mary von

    2004-01-01

    Leo Zoegelt ostetud Muuga mõisahoone korrastamisest ja uue hoone ehitamisest C. T. von Neffi kunstikogu paigutamise tarbeks. Tütre mälestused. Tõlgitud raamatust: Skizzen und Bilder aus dem Leben Carl Timoleon von Neff / Mary von Grünewaldt. Darmstadt, 1887

  10. „Der Einsatz von handlungs-, erfahrungs- und erlebnisorientierten Methoden in der Lehrerinnen- und Lehrerfortbildung von pädagogischen Führungskräften zur Initiierung von Lernen – Studien zur Verknüpfung von Erfahrung, Reflexion und Transfer“

    OpenAIRE

    Post, Eva - Maria

    2010-01-01

    Bei der Dissertation handelt es sich um eine Studie zum Einsatz von handlungs-, erfahrungs- und erlebnisorientierten Methoden. Diese wurden in der Lehrerinnen- und Lehrerfortbildung von pädagogischen Führungskräften untersucht und hinsichtlich ihrer Initiierung von Lernen überprüft. Dazu wurden der Transfer, die Wirksamkeit und die Nachhaltigkeit in Bezug auf die angebotenen Verfahren beschrieben und ausgewertet.

  11. Dr. Space the life of Wernher von Braun

    CERN Document Server

    Ward, Bob

    2013-01-01

    Written by veteran aerospace journalist Bob Ward, who spent years investigating his subject, this biography presents a revealing but even-handed portrait of the father of modern rocketry. As he chronicles Wernher von Braun's life, Ward explodes many myths and misconceptions about the controversial genius who was a hero to some, a villain to others. The picture of von Braun that emerges is of a brilliant scientist with limitless curiosity and a drive to achieve his goals at almost any price from, developing the world's first ballistic missile used against the Allies in World War II to help

  12. An ELISA for the quantitation of von Willebrand Factor

    DEFF Research Database (Denmark)

    Vinholt, Pernille Just; Overgaard, Martin; Diederichsen, Axel Cosmus Pyndt

    2013-01-01

    BACKGROUND: Von Willebrand factor (VWF) is pivotal in arterial thrombosis, and osteoprotegerin (OPG) is besides being a bone protein also related to cardiovascular diseases. OPG can bind VWF, but the significance of this interaction is not known. OBJECTIVES: The aim was to develop an assay...... for measurement of von Willebrand factor-osteoprotegerin complex (VWF:OPG) in human plasma. Furthermore, the significance of VWF:OPG complex as a marker of cardiovascular disease (CVD) was evaluated. PATIENTS/METHODS: A sandwich ELISA for quantification of VWF:OPG was developed using a polyclonal rabbit anti...

  13. The smooth entropy formalism for von Neumann algebras

    Energy Technology Data Exchange (ETDEWEB)

    Berta, Mario, E-mail: berta@caltech.edu [Institute for Quantum Information and Matter, California Institute of Technology, Pasadena, California 91125 (United States); Furrer, Fabian, E-mail: furrer@eve.phys.s.u-tokyo.ac.jp [Department of Physics, Graduate School of Science, University of Tokyo, Tokyo, Japan and Institute for Theoretical Physics, Leibniz University Hanover, Hanover (Germany); Scholz, Volkher B., E-mail: scholz@phys.ethz.ch [Institute for Theoretical Physics, ETH Zurich, Zurich (Switzerland)

    2016-01-15

    We discuss information-theoretic concepts on infinite-dimensional quantum systems. In particular, we lift the smooth entropy formalism as introduced by Renner and collaborators for finite-dimensional systems to von Neumann algebras. For the smooth conditional min- and max-entropy, we recover similar characterizing properties and information-theoretic operational interpretations as in the finite-dimensional case. We generalize the entropic uncertainty relation with quantum side information of Tomamichel and Renner and discuss applications to quantum cryptography. In particular, we prove the possibility to perform privacy amplification and classical data compression with quantum side information modeled by a von Neumann algebra.

  14. CHANGES OF VON WILLEBRAND FACTOR DURING PREGNANCY IN WOMEN WITHOUT AND WITH VON WILLEBRAND DISEASE

    Directory of Open Access Journals (Sweden)

    Giancarlo Castaman

    2013-07-01

    Full Text Available Delivery in von Willebrand disease (VWD represents a significant hemostatic challenge because of the variable pattern of changes observed during pregnancy of von Willebrand factor (VWF  and factor VIII (FVIII, the protein carried by VWF. The wide heterogeneity of phenotypes and of the underlying pathophysiological mechanisms associated with this disorder prompt a careful evaluation of pregnant women with VWD to plan the most appropriate treatment at time of parturition. VWF and FVIII increase significantly during pregnancy in normal women, already within the first trimester, reaching levels by far > 100 U/dL by the time of parturition. In women with VWD, levels at baseline of VWF and FVIII > 30 U/dL are usually associated with a high likelihood to achieve normal levels at the end of pregnancy and specific anti-hemorrhagic prophylaxis is seldom required. Women with basal level < 20 U/dL usually have a poor increase since most of these women carry mutations associated with increased VWF clearance or are compound heterozygous for different VWF mutations which prevent the achievement of satisfactory hemostatic levels. While women with mutations associated with increased clearance show a full, albeit transitory correction of their hemostatic deficiency after desmopressin administration, compound heterozygous need replacement therapy because they do not respond well to this agent. Patients with abnormal VWF:RCo/VWF:Ag ratio at baseline (e.g. < 0.6, typically associated with type 2 VWD, maintain the abnormality throughout pregnancy and VWF:RCo usually does not attain safe levels ³ 50 U/dL. These women require replacement therapy with VWF-FVIII concentrates. Delayed post-partum bleeding may occur when replacement therapy is not continued for some days. Tranexamic acid may be useful at discharge to avoid excessive lochia.

  15. Von-Neumann and Beyond: Memristor Architectures

    KAUST Repository

    Naous, Rawan

    2017-05-01

    An extensive reliance on technology, an abundance of data, and increasing processing requirements have imposed severe challenges on computing and data processing. Moreover, the roadmap for scaling electronic components faces physical and reliability limits that hinder the utilization of the transistors in conventional systems and promotes the need for faster, energy-efficient, and compact nano-devices. This work thus capitalizes on emerging non-volatile memory technologies, particularly the memristor for steering novel design directives. Moreover, aside from the conventional deterministic operation, a temporal variability is encountered in the devices functioning. This inherent stochasticity is addressed as an enabler for endorsing the stochastic electronics field of study. We tackle this approach of design by proposing and verifying a statistical approach to modelling the stochastic memristors behaviour. This mode of operation allows for innovative computing designs within the approximate computing and beyond Von-Neumann domains. In the context of approximate computing, sacrificing functional accuracy for the sake of energy savings is proposed based on inherently stochastic electronic components. We introduce mathematical formulation and probabilistic analysis for Boolean logic operators and correspondingly incorporate them into arithmetic blocks. Gate- and system-level accuracy of operation is presented to convey configurability and the different effects that the unreliability of the underlying memristive components has on the intermediary and overall output. An image compression application is presented to reflect the efficiency attained along with the impact on the output caused by the relative precision quantification. In contrast, in neuromorphic structures the memristors variability is mapped onto abstract models of the noisy and unreliable brain components. In one approach, we propose using the stochastic memristor as an inherent source of variability in

  16. Einfluss von Umweltbedingungen und Entwicklungsstadium auf Ertragsparameter und sekundäre Pflanzeninhaltsstoffe von Zitronenmelisse (Melissa officinalis L.

    Directory of Open Access Journals (Sweden)

    Russo, Marco

    2014-09-01

    Full Text Available Um die Qualität von Arznei- und Gewürzpflanzen langfristig sichern zu können, ist eine genauere Kenntnis der sie beeinflussenden Faktoren von Interesse. Am Beispiel der Zitronenmelisse (Melissa officinalis L. wurden in zwei Feldversuchen an unterschiedlichen Standorten die Einflüsse der Faktoren Lichtintensität, Sorte und Erntezeitpunkt auf Ertragsparameter sowie sekundäre Pflanzeninhaltsstoffe untersucht. Es konnten teilweise deutliche Effekte der unterschiedlichen Lichtbedingungen auf die Gesamtphenole und die antioxidative Kapazität beobachtet werden, die zum Teil signifikanten Wechselwirkungen zwischen den Prüffaktoren unterlagen.

  17. Mise-en-abyme of the culture: the space behind the camera in Pi’õnhitsi and Mokoi Tekoá Petei Jeguatá

    Directory of Open Access Journals (Sweden)

    André Brasil

    2013-12-01

    Full Text Available Through the analysis of two documentaries — Pi’õnhitsi e Mokoi Tekoá Petei Jeguatá —, the article suggests the constitutive nature of the “antecampo” (the space behind the camera in the indigenous films. It is the space in which the director enacts a double and interchangeable role: within the scene, as a member of the community, and out of the scene, as a filmmaker. Then, we unfold the hypothesis that, through the exposition of the “antecampo”, the indigenous cinema expresses, by mise-en-abyme, the engendering between culture and “culture”. 

  18. The identification of the continuity of the long fractures by mise-a-la-masse surveys. A test work at ONKALO

    Energy Technology Data Exchange (ETDEWEB)

    Lehtonen, T. [Astrock Oy, Sodankylae (Finland); Mattila, J. [Posiva Oy, Helsinki (Finland)

    2007-02-15

    This report concerns mise-a-la-masse surveys conducted in February 2006 at the area of the underground characterisation facility (ONKALO). Field surveys were made in 3 drillholes, in the ONKALO access tunnel and at 2 ground survey areas. Suomen Malmi Oy conducted the fieldwork. Astrock Oy supervised field surveys and processed acquired data. The interpretation and the reporting were made in cooperation with Posiva Oy. The purpose of the study was to test whether mise-a-la-masse measurements can be utilized in the identification of the continuity of the long fractures. Long fractures may pose a risk to canister integrity during post-glacial seismic activity. Therefore the development of methods for the identification of possible long fractures plays an important role in the evaluation of the suitability of the bedrock for the construction of deposition holes Current earthings were placed in 5 electrically conducting structures in the ONKALO access tunnel. Current earthings were situated in PL283, PL721, PL899, PL952 and in the mouth of the tunnel. Electrical connections were probed in 3 drillholes and at 2 ground survey areas. The acquired survey data were collected to xyz-coordinate oriented databases for 3D processing, interpreting and visualization of the results. At first the data were transferred to Oasis Montaj, where the potential field profiles were drawn and studied every current earthing at a time to determine characteristics of the electrical connections. Next probable connections were constructed and moved to SurpacVision for visualisation. They were delivered for Posiva Oy as Surpac string and DTM files. Ground surveys were hampered strongly by electrical disturbances of the infrastructure of the ONKALO area. Results of the all surveys are also collected in the tables, where every one of connections is classified. Mise-a-la-masse method seems to work moderately or fine to identify electrical connections from the current earthed fractures in the ONKALO

  19. La mise en ouvre de la réplique d'Ekain et de sa scénographie : Mon hommage à Jesús Altuna

    Directory of Open Access Journals (Sweden)

    Renaud Sanson

    2005-01-01

    Full Text Available Réflexions à propos de la mise en oeuvre de la réplique de la Grotte d’Ekain:* Une pratique innovante du fait pariétal et l’invention d’une technologie appliquée spécifique.* Lé création d’une scénographie au service de la révélation de l’Art d’Ekain alliant émotion et connaissance. Respect de l’oeuvre originale et du visiteurs : une dimension éthique de l’art de la réplique.

  20. De l'apprenant au concepteur : vers la mise en place d'une formation continue à distance des bibliothécaires/documentalistes en Tunisie

    OpenAIRE

    Ben Romdhane, Mohamed; Ouerfelli, Tarek

    2003-01-01

    Partant d'une expérience personnelle comme apprenants dans une Formation à Distance (FAD), nous développons un projet de mise en place d'une formation continue à distance sur l'utilisation des Nouvelles Technologies de l'Information et de la Communication (NTIC) dans les bibliothèques et centres de documentation en Tunisie. Après l'analyse de la situation actuelle de la FAD en Tunisie à travers le projet de l'Université Virtuelle de Tunis, nous présentons notre projet de FAD des bibliothécair...