TY - JOUR A1 - Miyamoto, Ko-ichiro A1 - Kaneko, Kazumi A1 - Matsuo, Akira A1 - Wagner, Torsten A1 - Kanoh, Shin`ichiro A1 - Schöning, Michael Josef A1 - Yoshinobu, Tatsuo T1 - Miniaturized chemical imaging sensor system using an OLED display panel JF - Procedia Engineering N2 - The chemical imaging sensor is a semiconductor-based chemical sensor that can visualize the two-dimensional distribution of specific ions or molecules in the solution. In this study, we developed a miniaturized chemical imaging sensor system with an OLED display panel as a light source that scans the sensor plate. In the proposed configuration, the display panel is placed directly below the sensor plate and illuminates the back surface. The measured area defined by illumination can be arbitrarily customized to fit the size and the shape of the sample to be measured. The waveform of the generated photocurrent, the currentvoltage characteristics and the pH sensitivity were investigated and pH imaging with this miniaturized system was demonstrated. Y1 - 2010 U6 - https://doi.org/10.1016/j.proeng.2010.09.160 SN - 1877-7058 N1 - Eurosensor XXIV Conference, 5-8 September 2010, Linz, Austria VL - 5 SP - 516 EP - 519 PB - Elsevier CY - Amsterdam ER - TY - GEN A1 - Behbahani, Mehdi A1 - Nam, J. A1 - Waluga, C. A1 - Behr, Marek A1 - Pasquali, M. A1 - Mottaghy, K. T1 - Modeling and Numerical Analysis of Platelet Activation, Adhesion and Aggregation in Artificial Organs T2 - ASAIO Journal N2 - Purpose of Study: Thrombosis-related complications are among the leading causes for morbidity and mortality in patients who depend on artificial organs. For the prediction of platelet behavior both the flow conditions inside the device and the thrombogenic properties of the blood-contacting surfaces must be considered. Platelet reactions under the influence of well-defined shear rates are experimentally evaluated and numerically simulated. The approach is intended for the analysis of VAD and oxygenator design. Methods Used: A mathematical model of platelet activation, adhesion and aggregation has been implemented into a finite element CFD (Computational Fluid Dynamics) code. The approach is based on the advective and diffusive transport equations for resting and activated platelets and platelet released agonists. Experiments with citrate-anticoagulated freshly-drawn whole blood are performed in a perfusion flow chamber as well as in a system of rotating cylinders for Couette and Taylor-vortex flow. Different biomaterials are used. The activation, adhesion and aggregation are quantified using scanning electron microscopy and flow cytometry. Summary of Results: Regions and flow conditions with a high potential for thrombus growth could be identified. The experiments clearly show the influence of the blood contacting material and governing shear rates. Numerical analysis can explain observed adhesion patterns and the degree of thrombus formation Y1 - 2010 U6 - https://doi.org/10.1097/01.mat.0000369377.65122.a3 SN - 1538-943X N1 - 56th annual conference, American Society of Artificial Organs (ASAIO), Baltimore, USA, May 27-29, 2010 VL - 56 IS - 2 SP - 85 PB - Lippincott Williams & Wilkins CY - Philadelphia ER - TY - JOUR A1 - Behbahani, Mehdi A1 - Mai, A. A1 - Bergmann, B. A1 - Waluga, C. A1 - Behr, Marek A1 - Tran, L. A1 - Vonderstein, K. A1 - Mottaghy, K. T1 - Modeling and Numerical Simulation of Blood Damage Y1 - 2010 N1 - Posterpresentation ; Umbrella Symposium "Modelling and Simulation in Medicine, Engineering and Sciences", Forschungszentrum Jülich, January 18-20, 2010 ER - TY - CHAP A1 - Werner, Frederik A1 - Spelthahn, Heiko A1 - Schöning, Michael Josef A1 - Krumbe, Christoph A1 - Wagner, Torsten A1 - Yoshinobu, Tatsuo A1 - Keusgen, Michael T1 - Neue Ansteuerungselektronik für LAPS-basierte Biosensoren zur gleichzeitig ortsaufgelösten Messung der pH-Konzentration T2 - Tagungsband: Sensoren und Messsysteme 2010 N2 - Ein lichtadressierbarer potentiometrischer Sensor (LAPS) kann die Konzentration eines oder mehrerer Analyten ortsaufgelöst auf der Sensoroberfläche nachweisen. Dazu wird mit einer modulierten Lichtquelle die Halbleiterstruktur des zu untersuchenden Bereiches angeregt und ein entsprechender Photostrom ausgelesen. Durch gleichzeitige Anregung mehrere Bereiche durch Lichtquellen mit unterschiedlichen Modulationsfrequenzen können diese auch zeitgleich ausgelesen werden. Mit der neuen, hier vorgestellten Ansteuerungselektronik integriert in einem "Field Programmable Gate Array" (FPGA) ist es möglich, mehrere Leuchtquellen gleichzeitig mit unterschiedlichen, während der Laufzeit festlegbaren Frequenzen, Phasen und Lichtintensitäten zu betreiben. Somit kann das Frequenzverhalten des Sensors untersucht und die Konzentration des Analyten über das Oberflächenpotential mit Hilfe von Strom/Spannungs-Kurven und Phase/Spannungs-Kurven bestimmt werden. Y1 - 2010 SN - 978-3-8007-3260-9 N1 - Sensoren und Messsysteme 2010 - 15. ITG/GMA-Fachtagung, 18.05.2010 - 19.05.2010 in Nürnberg SP - 109 EP - 114 PB - VDE Verlag CY - Berlin ER - TY - GEN A1 - Nam, J. A1 - Arora, D. A1 - Behbahani, Mehdi A1 - Probst, M. A1 - Benkowski, R. A1 - Behr, Marek A1 - Pasquali, M. T1 - New computational method in hemolysis analysis for artificial heart pump T2 - ASAIO Journal N2 - The MicroMed DeBakey ventricular assist device is an axial flow pump designed for providing long-term support to end-stage heartfailure patients. Previously, we presented computational analysis of the blood pump flow. From the analysis, we were able to identify regions of high shear and recirculating flow that may cause blood damage, for example, deformation and fragmentation of the red blood cell (RBC). This mechanical hemolysis can be predicted using a tensor-based blood damage model that is based on the physical properties of the RBCs, for example, the relaxation time of the RBC membrane. However, an extensive and detailed analysis was complicated by the fact that the previous method predicts hemolysis along a finite number of pathlines traversed by the RBCs, possibly omitting parts of the flow domain. Furthermore, it is computationally expensive and is not easily parallelizable. Here, we propose a new method to estimate hemolysis. The method is based on treating the shape of droplet (tensor) as a field variable, like velocity in the Navier-Stokes system. The governing equation for the RBC shape is treated by least-squares finite element method and the volume conservation of the RBC is augmented by Lagrangian multiplier. Unlike the previous method, the proposed method can visualize areas of high RBC strain that is potentially dangerous for mechanical hemolysis. Also, the amount of plasma-free hemoglobin and, consequently, normalized index of hemolysis can be computed as a byproduct. The method is tested in a simple shear flow for validation and an artery graft flow is chosen to show its potential usefulness. Finally, the method is applied to the blood damage estimation for the pump. Y1 - 2010 U6 - https://doi.org/10.1097/01.mat.0000369377.65122.a3 N1 - 56th Annual Conference of the American Society for Artificial Internal Organs (ASAIO), May 27 - 29, 2010, Baltimore, Maryland VL - 56 IS - 2 SP - 98 PB - Lippincott Williams & Wilkins CY - Philadelphia ER - TY - JOUR A1 - Wagner, Torsten A1 - Miyamoto, Ko-ichiro A1 - Schöning, Michael Josef A1 - Yoshinobu, Tatsuo T1 - Novel combination of digital light processing (DLP) and light-addressable potentiometric sensors (LAPS) for flexible chemical imaging JF - Procedia Engineering N2 - Chemical imaging systems allow the visualisation of the distribution of chemical species on the sensor surface. This work represents a new flexible approach of read out in a light-addressable potentiometric sensor (LAPS) with the help of a digital light processing (DLP) set-up. The DLP, known well for video projectors, consists of a mirror-array MEMS device which allows fast and flexible generation of light patterns. With the help of these light patterns the sensor surface of the LAPS device can be read out sequentially in a raster like scheme (scanning LAPS). The DLP approach has several advantages compared to conventional scanning LAPS set-ups, e.g., the spot size, the shape and the intensity of the light pointer can be changed easily and no mechanical movement is necessary, which reduces the size of the set-up and increases the stability and speed of measurement. Y1 - 2010 U6 - https://doi.org/10.1016/j.proeng.2010.09.161 SN - 1877-7058 N1 - Eurosensor XXIV Conference, 5-8 September 2010, Linz, Austria VL - 5 SP - 520 EP - 523 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Grajewski, Matthias A1 - Köster, Michael A1 - Turek, Stefam T1 - Numerical analysis and implementational aspects of a new multilevel grid deformation method JF - Applied Numerical Mathematics N2 - Recently, we introduced and mathematically analysed a new method for grid deformation (Grajewski et al., 2009) [15] we call basic deformation method (BDM) here. It generalises the method proposed by Liao et al. (Bochev et al., 1996; Cai et al., 2004; Liao and Anderson, 1992) [4], [6], [20]. In this article, we employ the BDM as core of a new multilevel deformation method (MDM) which leads to vast improvements regarding robustness, accuracy and speed. We achieve this by splitting up the deformation process in a sequence of easier subproblems and by exploiting grid hierarchy. Being of optimal asymptotic complexity, we experience speed-ups up to a factor of 15 in our test cases compared to the BDM. This gives our MDM the potential for tackling large grids and time-dependent problems, where possibly the grid must be dynamically deformed once per time step according to the user's needs. Moreover, we elaborate on implementational aspects, in particular efficient grid searching, which is a key ingredient of the BDM. Y1 - 2010 U6 - https://doi.org/10.1016/j.apnum.2010.03.017 SN - 0168-9274 VL - 60 IS - 8 SP - 767 EP - 781 PB - Elsevier CY - Amsterdam ER - TY - GEN A1 - Behbahani, Mehdi A1 - Mai, A. A1 - Waluga, C. A1 - Bergmann, B. A1 - Tran, L. A1 - Vonderstein, K. A1 - Behr, Marek A1 - Mottaghy, K. T1 - Numerical Modeling of Flow-Related Thrombus Formation under Physiological and Non-Physiological Flow Conditions T2 - Acta Physiologica N2 - Aims: Thrombotic complications due to activation of platelets and plasmatic clotting factors belong still to the most investigated topics in the field of study of patho-physiological mechanisms. Mathematical modeling of thrombotic reactions is established and validated in test cases. Aim of this study is to experimentally evaluate and computationally simulate platelets under the influence of well-defined shear flow conditions. Platelet behaviour and reactions are experimentally reproduced, measured and used for validation of the numerical simulation. Methods: A mathematical model of platelet activation, adhesion and aggregation has been implemented into a finite element CFD (Computational Fluid Dynamics) code. The approach is based on the advective and diffusive transport equations for resting platelets, activated platelets and platelet released agonists. Adhesion rates for the reactive surfaces depend on the hemocompatibility properties of the surface and the local shear rate. Experiments with citrate-anticoagulated freshly-drawn whole blood are performed in a perfusion flow chamber as well as in a system of rotating cylinders for Couette and Taylor-vortex flow. Different biomaterials are used. The activation, drop of platelet concentration, adhesion and aggregation are quantified using scanning electron microscopy (SEM) and flow cytometry. Results: Regions and flow conditions with a high potential for thrombus growth could be identified. The experiments clearly show the influence of the blood contacting material and flow properties. By means of SEM diverse platelet adhesion patterns are observed. Numerical analysis can explain the patterns and the degree of thrombus formation. Conclusion: The numerical method shows good agreement with experimental data indicating a possible prediction of initiation of activation and detection of the local adhesion areas in connection with the role of Von-Willebrand-Factor. Y1 - 2010 SN - 1748-1716 N1 - Joint Congress of the Scandinavian and German Physiological Societies, Copenhagen, Denmark, March 27-30, 2010 VL - 198 IS - Supplement 677 SP - 185 PB - Wiley-Blackwell CY - Oxford ER - TY - JOUR A1 - Behbahani, Mehdi A1 - Probst, M. A1 - Mai, A. A1 - Behr, Marek A1 - Tran, L. A1 - Vonderstein, K. A1 - Mottaghy, K. T1 - Numerical Prediction of Blood Damage in Biomedical Devices Y1 - 2010 N1 - Biomedica: The Life Science Summit, Aachen, Germany , 2010-03-17 - 2010-03-18 ER - TY - THES A1 - Pettrak, Jürgen T1 - Nutzung nachwachsender Rohstoffe bei der Herstellung thermoplastischer Elastomere aus Folgeprodukten der Olefinmetathese N2 - Metathese von Ölsäure und Derivaten ist ein interessanter Weg für die Synthese bifunktioneller Verbindungen aus nachwachsenden Rohstoffen. Verwendet wurden Ru-Katalysatoren der zweiten Generation, welche eine hohe Toleranz gegenüber funktionellen Gruppen und Verunreinigungen aufweisen. Trotz des Einsatzes technischer Edukte waren Umsetzungen mit niedrigen Katalysatormengen (0.001 – 0.01 mol-%) möglich, mit Ausbeuten entsprechend der Literatur. Kreuzmetathesen ermöglichten variable Kettenlängen und Funktionalitäten der Monomere, die Produktgewinnung ist jedoch aufwändig. Selbstmetathese lieferte C18-bifunktionelle Verbindungen, welche einfach durch Destillation oder Kristallisation isoliert werden können. Neben der katalystischen Umsetzung wurde auch die Produktgewinnung untersucht und für ausgewählte Produkte auch im größeren Maßstab durchgeführt. Y1 - 2010 PB - Technische Universität München CY - München ER - TY - JOUR A1 - Buniatyan, Vahe Vazgen A1 - Abouzar, Maryam H. A1 - Martirosyan, Norayr W. A1 - Schubert, Jürgen A1 - Gevorgian, Spartak A1 - Schöning, Michael Josef A1 - Poghossian, Arshak T1 - pH-sensitive properties of barium strontium titanate (BST) thin films prepared by pulsed laser deposition technique JF - Physica Status Solidi (A) N2 - pH-sensitive properties of barium strontium titanate (BST) high-k thin films as alternative gate material for field-effect capacitive (bio-)chemical sensors based on an electrolyte-insulator-semiconductor system have been investigated. The BST films of different compositions (Ba0.31Sr0.69TiO3, Ba0.25Sr0.75TiO3 and Mg-doped Ba0.8Sr0.2Mg0.1Ti0.9O3) were deposited by pulsed laser deposition technique from targets fabricated by self-propagating high-temperature synthesis. The realised sensors have been electrochemically characterised by means of impedance-spectroscopy, capacitance–voltage and constant-capacitance method. The sensors possess a Nernstian-like pH sensitivity in the concentration range between pH 3 and 11 with a response time of 5–10 s. An equivalent circuit model for the BST-based capacitive field-effect sensor is discussed. Y1 - 2010 U6 - https://doi.org/10.1002/pssa.200983310 SN - 1862-6300 N1 - Special Issue: Engineering of Functional Interfaces EnFI 2009 VL - 207 IS - 4 SP - 824 EP - 830 PB - Wiley-VCH CY - Berlin ER - TY - JOUR A1 - Arampatzis, Adamantios A1 - Peper, Andreas A1 - Bierbaum, Stefanie A1 - Albracht, Kirsten T1 - Plasticity of human Achilles tendon mechanical and morphological properties in response to cyclic strain JF - Journal of Biomechanics N2 - The purpose of the current study in combination with our previous published data (Arampatzis et al., 2007) was to examine the effects of a controlled modulation of strain magnitude and strain frequency applied to the Achilles tendon on the plasticity of tendon mechanical and morphological properties. Eleven male adults (23.9±2.2 yr) participated in the study. The participants exercised one leg at low magnitude tendon strain (2.97±0.47%), and the other leg at high tendon strain magnitude (4.72±1.08%) of similar frequency (0.5 Hz, 1 s loading, 1 s relaxation) and exercise volume (integral of the plantar flexion moment over time) for 14 weeks, 4 days per week, 5 sets per session. The exercise volume was similar to the intervention of our earlier study (0.17 Hz frequency; 3 s loading, 3 s relaxation) allowing a direct comparison of the results. Before and after the intervention ankle joint moment has been measured by a dynamometer, tendon–aponeurosis elongation by ultrasound and cross-sectional area of the Achilles tendon by magnet resonance images (MRI). We found a decrease in strain at a given tendon force, an increase in tendon–aponeurosis stiffness and tendon elastic modulus of the Achilles tendon only in the leg exercised at high strain magnitude. The cross-sectional area (CSA) of the Achilles tendon did not show any statistically significant (P>0.05) differences to the pre-exercise values in both legs. The results indicate a superior improvement in tendon properties (stiffness, elastic modulus and CSA) at the low frequency (0.17 Hz) compared to the high strain frequency (0.5 Hz) protocol. These findings provide evidence that the strain magnitude applied to the Achilles tendon should exceed the value, which occurs during habitual activities to trigger adaptational effects and that higher tendon strain duration per contraction leads to superior tendon adaptational responses. Y1 - 2010 U6 - https://doi.org/10.1016/j.jbiomech.2010.08.014 SN - 0021-9290 VL - 43 IS - 16 SP - 3073 EP - 3079 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Wiescher, A. A1 - Kotliar, Konstantin A1 - Neuhann, T. A1 - Lanzl, Ines M. T1 - Rasch progrediente Visusminderung beider Augen bei einem jungen Patienten JF - Der Ophthalmologe N2 - Ein 34-jähriger männlicher Patient stellte sich zur Abklärung einer seit dem 9. Lebensjahr bestehenden und im letzten Jahr rasch progredienten Visusminderung beider Augen bei uns vor. Er beschrieb eine subjektiv zunehmende, im Spiegel für ihn selbst sichtbare, weißliche Trübung in der Pupille beidseits und eine starke Blendempfindlichkeit. Nebenbefundlich gab er rezidivierende Konjunktivitiden und morgens verklebte Lider an. Eine Allergie auf Gräserpollen und eine Unverträglichkeit auf Alkohol sowie mehrere Lebensmittel seien ebenfalls bekannt. Zusätzlich leidet der Patient an stark ausgeprägtem atopischem Ekzem. Dieses wurde nie systemisch, sondern nur bei Bedarf mit kortisonhaltiger Salbe therapiert. Y1 - 2010 U6 - https://doi.org/10.1007/s00347-007-1586-x SN - 1433-0423 VL - 105 IS - 4 SP - 389 EP - 392 PB - Springer CY - Berlin ER - TY - JOUR A1 - Bohrn, Ulrich A1 - Stütz, Evamaria A1 - Fleischer, Maximilian A1 - Schöning, Michael Josef T1 - Real-time detection of CO by eukaryotic cells JF - Procedia Engineering N2 - In this contribution, we focus on the detection of toxic gases with living eukaryotic cells. A cell-based gas sensor system, able to measure the effects of direct exposure of gases to cells in real-time, was set up. Impedance data as well as oxygen consumption of Chinese hamster lung fibroblast cells (V79) were analysed upon exposure to carbon monoxide (CO). The CO (diluted in wet synthetic air) affects the cell respiration as indicated by an attenuated respiration signal after the CO exposure as well as an instant increase of the capacitive part of the impedance signal during the gas exposure. Y1 - 2010 SN - 1877-7058 N1 - Eurosensor XXIV Conference, 5-8 September 2010, Linz, Austria VL - 5 SP - 17 EP - 20 PB - Elsevier CY - Amsterdam ER - TY - CHAP A1 - Kirchner, Patrick A1 - Spelthahn, Heiko A1 - Schöning, Michael Josef A1 - Henkel, Hartmut A1 - Schneider, Andreas A1 - Friedrich, Peter A1 - Kolstad, Jens A1 - Berger, Jörg T1 - Realisierung eines Polyimid-basierten kalorimetrischen Gassensors zur Inline-Überwachung der H2O2-Konzentration in aseptischen Abfüllsystemen T2 - Tagungsband: Sensoren und Messsysteme 2010 N2 - In aseptischen Abfüllsystemen wird Wasserstoffperoxid in der Gasphase aufgrund der stark oxidativen Wirkung zur Packstoffentkeimung eingesetzt. Dabei wird die Effizienz der Entkeimung im Wesentlichen von der vorliegenden H2O2-Konzentration im Packstoff bestimmt. Zur Inline-Überwachung der H2O2-Konzentration wurde ein kalorimetrischer Gassensor auf Basis einer flexiblen Polyimidfolie aus temperatursensitiven Dünnschicht-Widerständen und Mangan(IV)-oxid als katalytische Transducerschicht realisiert. Der Sensor weist ein lineares Ansprechverhalten mit einer Sensitivität von 7,15 °C/Vol.-% in einem H2O2-Konzentrationsbereich von 0 bis 8 Vol.-% auf. Weiterhin wurde zur Auslesung des Sensorsignals eine RFID-Elektronik, bestehend aus einem Sensor-Tag und einer Sende-/Empfangseinheit ausgelegt, sowie eine Abfolge des Messzyklus aufgestellt. Im weiteren Verlauf soll der kalorimetrische Gassensor mit der RFID-Elektronik gekoppelt und in eine Testverpackung zur Inline-Überwachung der H2O2-Konzentration in aseptischen Abfüllsystemen implementiert werden. Y1 - 2010 SN - 978-3-8007-3260-9 N1 - Sensoren und Messsysteme 2010 - 15. ITG/GMA-Fachtagung, 18.05.2010 - 19.05.2010 in Nürnberg SP - 607 EP - 612 PB - VDE Verlag CY - Berlin ER - TY - JOUR A1 - Kirchner, Patrick A1 - Oberländer, Jan A1 - Friedrich, Peter A1 - Rysstad, Gunnar A1 - Berger, Jörg A1 - Keusgen, Michael A1 - Schöning, Michael Josef T1 - Realization of a calorimetric gas sensor on polyimide foil for applications in aseptic food industry JF - Procedia Engineering N2 - A calorimetric gas sensor is presented for the monitoring of gas-phase H2O2 at elevated temperature during sterilization processes in aseptic food industry. The sensor consists of two temperature-sensitive thin-film resistances built up on a polyimide foil with a thickness of 25 μm, which are passivated with a layer of SU-8 photo resist and catalytically activated with manganese(IV) oxide. Instead of an active heating structure, the calorimetric sensor utilizes the elevated temperature of an evaporated H2O2 aerosol. In an experimental set-up, the sensor has shown a sensitivity of 4.78 °C/(%v/v) in a H2O2 concentration range of 0 to 10% v/v at an evaporation temperature of 240 ∘C. Furthermore, the sensor possesses the same, unchanged sensor signal even at varied evaporation temperatures of the gas stream. The sensor characterization demonstrates the suitability of the calorimetric gas sensor for monitoring the efficiency of sterilization processes. Y1 - 2010 U6 - https://doi.org/10.1016/j.proeng.2010.09.098 SN - 1877-7058 N1 - Eurosensor XXIV Conference, 5-8 September 2010, Linz, Austria VL - 5 SP - 264 EP - 267 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Aggeloussis, Nickos A1 - Giannakou, Erasmia A1 - Albracht, Kirsten A1 - Arampatzis, Adamantios T1 - Reproducibility of fascicle length and pennation angle of gastrocnemius medialis in human gait in vivo JF - Gait and Posture N2 - The purpose of the current study was to examine the reproducibility of fascicle length and pennation angle of gastrocnemius medialis while human walking. To the best of our knowledge, this is the first study of the reproducibility of fascicle length and pennation angle of gastrocnemius medialis in vivo during human gait. Twelve males performed 10 gait trials on a treadmill, in 2 separate days. B-mode ultrasonography, with the ultrasound probe firmly adjusted in the transverse and frontal planes using a special cast, was used to measure the fascicle length and the pennation angle of the gastrocnemius medialis (GM). A Vicon 624 system with three cameras operating at 120 Hz was also used to record the ankle and knee joint angles. The results showed that measurements of fascicle length and pennation angle showed high reproducibility during the gait cycle, both within the same day and between different days. Moreover, the root mean square differences between the repeated waveforms of both variables were very small, compared with their ranges (fascicle length: RMS = ∼3 mm, range: 38–63 mm; pennation angle: RMS = ∼1.5°, range: 22–32°). However, their reproducibility was lower compared to the joint angles. It was found that representative data have to be derived by a wide number of gait trials (fascicle length ∼six trials, pennation angle more than 10 trials), to assure the reliability of the fascicle length and pennation angle in human gait. Y1 - 2010 U6 - https://doi.org/10.1016/j.gaitpost.2009.08.249 SN - 0966-6362 VL - 31 IS - 1 SP - 73 EP - 77 PB - Elsevier CY - Amsterdam ER - TY - CHAP A1 - Kurulgan Demirci, Eylem A1 - Linder, Peter A1 - Demirci, Taylan A1 - Gierkowski, Jessica R. A1 - Digel, Ilya A1 - Gossmann, Matthias A1 - Temiz Artmann, Aysegül T1 - rhAPC reduces the endothelial cell permeability via a decrease of cellular mechanical contractile tensions : [abstract] N2 - In this study, the CellDrum technology quanitfying cellular mechanical tension on a pico-scale was used to investigate the effect of LPS (lipopolysaccharide) on HAoEC (Human Aortic Endothelial Cell) tension. KW - Endothelzelle KW - Sepsis KW - kontraktile Spannung KW - rhAPC KW - contractile tension KW - rhAPC KW - celldrum technology Y1 - 2010 ER - TY - BOOK A1 - Laack, Walter van T1 - Schnittstelle Tod: Aufbruch zu neuem Leben? Y1 - 2010 SN - 978-3-936624-10-6 N1 - Tagungsbeiträge des 1. Europäischen Seminars in Aachen zum Thema Nahtoderfahrungen mit dem Titel: "Schnittstelle Tod", am 7. November 2009 / [Hrsg.: Walter van Laack] PB - Books on Demand CY - Norderstedt ER - TY - JOUR A1 - Riepl, Herbert Matthias A1 - Pettrak, Jürgen A1 - Faulstich, Martin A1 - Herrmann, Wolfgang Anton T1 - Self metathesis of fatty alcohols and amines to provide monomers for polyester and polyamide products JF - Macromolecular Symposia N2 - Self metathesis of oleochemicals offers a variety of bifunctional compounds, that can be used as monomer for polymer production. Many precursors are in huge scales available, like oleic acid ester (biodiesel), oleyl alcohol (tensides), oleyl amines (tensides, lubricants). We show several ways to produce and separate and purify C18-α,ω-bifunctional compounds, using Grubbs 2nd Generation catalysts, starting from technical grade educts. KW - fatty acid KW - metathesis KW - polyamide KW - polyester KW - renewable resources Y1 - 2010 U6 - https://doi.org/10.1002/masy.200900041 SN - 1521-3900 (eISSN) SN - 0258-0322 SN - 1022-1360 N1 - Special Issue: "Olefin Metathesis" VL - 293 IS - 1 SP - 39 EP - 42 PB - Wiley-VCH CY - Weinheim ER - TY - CHAP A1 - Tran, Thanh Ngoc A1 - Staat, Manfred T1 - Shakedown analysis of two dimensional structures by an edge-based smoothed finite element method Y1 - 2010 N1 - 4th European Conference on Computational Mechanics (Solids, Structures and Coupled Problems in Engineering), ECCOMAS ECCM 2010, Paris, France, May 17 – 21, 2010 ER - TY - JOUR A1 - Turek, Monik A1 - Heiden, Wolfgang A1 - Guo, Sharon A1 - Riesen, Alfred A1 - Schubert, Jürgen A1 - Zander, Willi A1 - Krüger, Peter A1 - Keusgen, Michael A1 - Schöning, Michael Josef T1 - Simultaneous detection of cyanide and heavy metals for environmental analysis by means of µISEs JF - Physica Status Solidi (A) N2 - In environmental analysis, cyanide and heavy metals play an important role, because these substances are highly toxic for biological systems. They can lead to chronic and acute diseases. Due to the chemical properties of cyanide it is frequently used for industrial processes such as extraction of silver and gold. Heavy metals can be found as trace elements in nature and are often applied in industries e.g., galvanization processes. Up to now, cyanide and heavy metals can be detected by several sensors separately and their detection is often limited to laboratory investigations. In this publication, with regard to an in situ analysis, a new miniaturized silicon-based sensor system for the simultaneous detection of cyanide and heavy metals in aqueous solutions is presented that is based on chalcogenide glass-based micro ion-selective electrodes (µISEs). The µISEs are incorporated into a specially designed measuring system for the simultaneous detection of heavy metals and cyanide in solutions and validated by simultaneous measurements of Cu2+- and CN−-ions, Cd2+- and CN−- ions and Pb2+- and CN−-ions. The particular sensor system has shown good sensor properties in the µ-molar ion-concentration range. For simultaneous measurements in complex heavy metal and cyanide solutions an intelligent software using fuzzy logic is discussed. Y1 - 2010 U6 - https://doi.org/10.1002/pssa.200983303 SN - 1862-6300 N1 - Special Issue: Engineering of Functional Interfaces EnFI 2009 VL - 207 IS - 4 SP - 817 EP - 823 PB - Wiley-VCH CY - Berlin ER - TY - JOUR A1 - Horstmann, Marie-Therese A1 - Bialonski, Stephan A1 - Noenning, Nina A1 - Mai, Heinke A1 - Prusseit, Jens A1 - Wellmer, Jörg A1 - Hinrichs, Hermann A1 - Lehnertz, Klaus T1 - State dependent properties of epileptic brain networks: Comparative graph–theoretical analyses of simultaneously recorded EEG and MEG JF - Clinical Neurophysiology N2 - Objective To investigate whether functional brain networks of epilepsy patients treated with antiepileptic medication differ from networks of healthy controls even during the seizure-free interval. Methods We applied different rules to construct binary and weighted networks from EEG and MEG data recorded under a resting-state eyes-open and eyes-closed condition from 21 epilepsy patients and 23 healthy controls. The average shortest path length and the clustering coefficient served as global statistical network characteristics. Results Independent on the behavioral condition, epileptic brains exhibited a more regular functional network structure. Similarly, the eyes-closed condition was characterized by a more regular functional network structure in both groups. The amount of network reorganization due to behavioral state changes was similar in both groups. Consistent findings could be achieved for networks derived from EEG but hardly from MEG recordings, and network construction rules had a rather strong impact on our findings. Conclusions Despite the locality of the investigated processes epileptic brain networks differ in their global characteristics from non-epileptic brain networks. Further methodological developments are necessary to improve the characterization of disturbed and normal functional networks. Significance An increased regularity and a diminished modulation capability appear characteristic of epileptic brain networks. Y1 - 2010 U6 - https://doi.org/10.1016/j.clinph.2009.10.013 SN - 1388-2457 VL - 121 IS - 2 SP - 172 EP - 185 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Pressler, Axel A1 - Esefeld, Katrin A1 - Scherr, Johannes A1 - Ali, Mohammad A1 - Hanssen, Henner A1 - Kotliar, Konstantin A1 - Lanzl, Ines A1 - Halle, Martin A1 - Kaemmerer, Harald A1 - Schmidt-Trucksäss, Arno A1 - Hager, Alfred T1 - Structural alterations of retinal arterioles in adults late after repair of aortic isthmic coarctation JF - The American Journal of Cardiology N2 - Patients after coarctation repair still have an increased risk of cardiovascular or cerebrovascular events. This has been explained by the persisting hypertension and alterations in the peripheral vessels. However, involvement of the central vessels such as the retinal arteries is virtually unknown. A total of 34 patients after coarctation repair (22 men and 12 women; 23 to 58 years old, age range 0 to 32 years at surgical repair) and 34 nonhypertensive controls underwent structural and functional retinal vessel analysis. Using structural analysis, the vessel diameters were measured. Using functional analysis, the endothelium-dependent vessel dilation in response to flicker light stimulation was assessed. In the patients after coarctation repair, the retinal arteriolar diameter was significantly reduced compared to that of the controls (median 182 μm, first to third quartile 171 to 197; vs 197 μm, first to third quartile 193 to 206; p <0.001). These findings were independent of the peripheral blood pressure and age at intervention. No differences were found for venules. The functional analysis findings were not different between the patients and controls (maximum dilation 3.5%, first to third quartile 2.1% to 4.5% vs 3.6%, first to third quartile 2.2% to 4.3%; p = 0.81), indicating preserved autoregulative mechanisms. In conclusion, the retinal artery diameter is reduced in patients after coarctation repair, independent of their current blood pressure level and age at intervention. As a structural marker of chronic vessel damage associated with past, current, or future hypertension, retinal arteriolar narrowing has been linked to stroke incidence. These results indicate an involvement of cerebral microcirculation in aortic coarctation, despite timely repair, and might contribute to explain the increased rate of cerebrovascular events in such patients. Y1 - 2010 U6 - https://doi.org/10.1016/j.amjcard.2009.10.070 SN - 0002-9149 VL - 105 IS - 5 SP - 740 EP - 744 PB - Elsevier CY - Amsterdam ER - TY - CHAP A1 - Artmann, Gerhard A1 - Stadler, Andreas M. A1 - Embs, Jan P. A1 - Zaccai, Giuseppe A1 - Büldt, Georg A1 - Digel, Ilya A1 - Temiz Artmann, Aysegül T1 - The crucial role of water in a phase transition of hemoglobin at body temperature : [abstract] N2 - The observation of a temperature transition of hemoglobin occurring at a critical temperature close to body temperature KW - Hämoglobin KW - Erythrozyt KW - Körpertemperatur Y1 - 2010 ER - TY - JOUR A1 - Herzog, Hans A1 - Pietrzyk, Uwe A1 - Shah, N. Jon A1 - Ziemons, Karl T1 - The current state, challenges and perspectives of MR-PET JF - Neuroimage N2 - Following the success of PET/CT during the last decade and the recent increasing proliferation of SPECT/CT, another hybrid imaging instrument has been gaining more and more interest: MR-PET. First combined, simultaneous PET and MR studies carried out in small animals demonstrated the feasibility of the new approach. Concurrently, some prototypes of an MR-PET scanner for simultaneous human brain studies have been built, their performance is being tested and preliminary applications have already been shown. Through this pioneering work, it has become clear that advances in the detector design are necessary for further optimization. Recently, the different issues related to the present state and future prospects of MR-PET were presented and discussed during an international 2-day workshop at the Forschungszentrum Jülich, Germany, held after, and in conjunction with, the 2008 IEEE Nuclear Science Symposium and Medical Imaging Conference in Dresden, Germany on October 27–28, 2008. The topics ranged from small animal MR-PET imaging to human MR-BrainPET imaging, new detector developments, challenges/opportunities for ultra-high field MR-PET imaging and considerations of possible future research and clinical applications. This report presents a critical summary of the contributions made to the workshop. Y1 - 2010 U6 - https://doi.org/10.1016/j.neuroimage.2009.10.036 SN - 1053-8119 VL - 49 IS - 3 SP - 2072 EP - 2082 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Behbahani, Mehdi A1 - Probst, M. A1 - Mai, A. A1 - Tran, L. A1 - Vonderstein, K. A1 - Keschenau, P. A1 - Linde, T. A1 - Steinseifer, U. A1 - Behr, Marek A1 - Mottaghy, K. T1 - The influence of high shear on thrombosis and hemolysis in artificial organs JF - The International Journal of Artificial Organs Y1 - 2010 SN - 0391-3988 VL - 33 IS - 7 SP - 426 EP - 426 PB - Sage CY - Thousand Oaks ER - TY - JOUR A1 - Hirschfeld, Julian A. A1 - Lustfeld, Hans A1 - Reißel, Martin A1 - Steffen, Bernhard T1 - Tomographic diagnostics of current distributions in a fuel cell stack JF - International Journal of Energy Research N2 - A novel tomographic scheme for analysing the state of any single membrane electrode assembly (MEA) in a stack is suggested. Plates of very high conductivity placed between every fuel cell and slitted in an appropriate manner cause surface currents at well-defined locations of the stack. We show that knowing these surface currents, information about anomalies of the currents in a MEA can be obtained using the methods of tomography. The results are mathematically not unique. However, when assuming plausible defect structures, one can exclude improbable deficiencies by applying a special form of simulated annealing. We present numerical calculations of typical examples demonstrating that the essential defects of the MEA in any single cell of the stack can be detected and their extent can be determined. Y1 - 2010 U6 - https://doi.org/10.1002/er.1634 SN - 0363-907X VL - 34 IS - 3 SP - 284 EP - 292 PB - Wiley CY - London ER - TY - CHAP A1 - Berretz, Frank A1 - Skorupa, Sascha A1 - Sander, Volker A1 - Belloum, Adam T1 - Towards an actor-driven workflow management system for grids T2 - Proceedings of 2010 International Symposium on Collaborative Technologies and Systems N2 - Currently, most workflow management systems in Grid environments provide push-oriented job distribution strategies, where jobs are explicitly delegated to resources. In those scenarios the dedicated resources execute submitted jobs according to the request of a workflow engine or Grid wide scheduler. This approach has various limitations, particularly if human interactions should be integrated in workflow execution. To support human interactions with the benefit of enabling inter organizational computation and community approaches, this poster paper proposes the idea of a pull-based task distribution strategy. Here, heterogeneous resources, including human interaction, should actively select tasks for execution from a central repository. This leads to special demands regarding security issues like access control. In the established push-based job execution the resources are responsible for granting access to workflows and job initiators. In general this is done by access control lists, where users are explicitly mapped to local accounts according to their policies. In the pull-based approach the resources actively apply for job executions by sending requests to a central task repository. This means that every resource has to be able to authenticate against the repository to be authorized for task execution. In other words the authorization is relocated from the resources to the repository. The poster paper introduces current work regarding to the mentioned security aspects in the pull-based approach within the scope of the project “HiX4AGWS”. KW - scheduling KW - engines KW - resource management KW - grid computing KW - access control KW - distribution strategy KW - authorization KW - security KW - humans KW - workflow management software Y1 - 2010 SN - 978-1-4244-6619-1 U6 - https://doi.org/10.1109/CTS.2010.5478458 N1 - 2010 International Symposium on Collaborative Technologies and Systems, 17-21 May 2010, Chicago, IL, USA SP - 611 EP - 616 PB - IEEE CY - Piscataway, NJ ER - TY - JOUR A1 - Akimbekov, Nuraly S. A1 - Zhubanova, A. A. A1 - Mansurov, Z. A. A1 - Digel, Ilya A1 - Artmann, Gerhard A1 - Temiz Artmann, Aysegül T1 - Use of Carbonized Rise Shell for the local treatment of wounds JF - Eurasian ChemTech Journal N2 - On the model of musculocutaneous wound in rats, the effect of applicative sorption by carbonized rise shell (CRS) on the healing of festering wound was studied. It has been shown, that cytological changes end with rapid scar formation. The use of CRS at the period of severe purulent wound contributes to its favorable course, prevents the development of complications of the animals from sepsis. Y1 - 2010 U6 - https://doi.org/10.18321/ectj35 SN - 2522-4867 VL - 12 IS - 2 SP - 133 EP - 138 PB - Institute of Combustion Problems CY - Almaty ER - TY - JOUR A1 - Siqueira, Jose R. A1 - Maki, Rafael M. A1 - Paulovich, Fernando V. A1 - Werner, Frederik A1 - Poghossian, Arshak A1 - Oliveira, Maria C. F. de A1 - Zucolotto, Valtencir A1 - Oliveira, Osvaldo N. Jr. A1 - Schöning, Michael Josef T1 - Use of information visualization methods eliminating cross talk in multiple sensing units investigated for a light-addressable potentiometric sensor JF - Analytical Chemistry N2 - The integration of nanostructured films containing biomolecules and silicon-based technologies is a promising direction for reaching miniaturized biosensors that exhibit high sensitivity and selectivity. A challenge, however, is to avoid cross talk among sensing units in an array with multiple sensors located on a small area. In this letter, we describe an array of 16 sensing units of a light-addressable potentiometric sensor (LAPS), which was made with layer-by-layer (LbL) films of a poly(amidomine) dendrimer (PAMAM) and single-walled carbon nanotubes (SWNTs), coated with a layer of the enzyme penicillinase. A visual inspection of the data from constant-current measurements with liquid samples containing distinct concentrations of penicillin, glucose, or a buffer indicated a possible cross talk between units that contained penicillinase and those that did not. With the use of multidimensional data projection techniques, normally employed in information visualization methods, we managed to distinguish the results from the modified LAPS, even in cases where the units were adjacent to each other. Furthermore, the plots generated with the interactive document map (IDMAP) projection technique enabled the distinction of the different concentrations of penicillin, from 5 mmol L−1 down to 0.5 mmol L−1. Data visualization also confirmed the enhanced performance of the sensing units containing carbon nanotubes, consistent with the analysis of results for LAPS sensors. The use of visual analytics, as with projection methods, may be essential to handle a large amount of data generated in multiple sensor arrays to achieve high performance in miniaturized systems Y1 - 2010 U6 - https://doi.org/10.1021/ac9024076 SN - 0003-2700 VL - 82 IS - 1 SP - 61 EP - 65 PB - ACS Publications CY - Washington ER - TY - JOUR A1 - Garhofer, Gerhard A1 - Bek, Toke A1 - Boehm, Andreas G. A1 - Gherghel, Doina A1 - Grundwald, Juan A1 - Jeppesen, Peter A1 - Kergoat, Hélène A1 - Kotliar, Konstantin A1 - Lanzl, Ines A1 - Lovasik, John V. A1 - Nagel, Edgar A1 - Vilser, Walthard A1 - Orgul, Selim A1 - Schmetterer, Leopold T1 - Use of the retinal vessel analyzer in ocular blood flow research JF - Acta Ophthalmol N2 - The present article describes a standard instrument for the continuous online determination of retinal vessel diameters, the commercially available retinal vessel analyzer. This report is intended to provide informed guidelines for measuring ocular blood flow with this system. The report describes the principles underlying the method and the instruments currently available, and discusses clinical protocol and the specific parameters measured by the system. Unresolved questions and the possible limitations of the technique are also discussed. Y1 - 2010 U6 - https://doi.org/10.1111/j.1755-3768.2009.01587.x SN - 1755-3768 VL - 88 IS - 7 SP - 717 EP - 722 PB - Wiley-Blackwell CY - Oxford ER - TY - JOUR A1 - Ullrich, Sebastian A1 - Grottke, Oliver A1 - Rossaint, Rolf A1 - Staat, Manfred A1 - Deserno, Thomas M. A1 - Kuhlen, Torsten T1 - Virtual Needle Simulation with Haptics for Regional Anaesthesia Y1 - 2010 N1 - IEEE Virtual Reality 2010, Workshop on Medical Virtual Environments, Waltham, MA, USA, March 21, 2010 ER -