TY - JOUR A1 - Stadler, Alexander Maximilian A1 - Garvey, Christopher J. A1 - Embs, Jan Peter A1 - Koza, Michael Marek A1 - Unruh, Tobias A1 - Artmann, Gerhard A1 - Zaccai, Guiseppe T1 - Picosecond dynamics in haemoglobin from different species: A quasielastic neutron scattering study JF - Biochimica et biophysica acta (BBA): General Subjects Y1 - 2014 U6 - https://doi.org/10.1016/j.bbagen.2014.06.007 SN - 1872-8006 (E-Journal); 0304-4165 (Print) VL - 1840 IS - 10 SP - 2989 EP - 2999 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Holtrup, S. A1 - Sadeghfam, Arash A1 - Heuermann, Holger A1 - Awakowicz, P. T1 - Characterization and optimization technique for microwave-driven high-intensity discharge lamps using hot S-parameters JF - IEEE transactions on microwave theories and techniques N2 - High-intensity discharge lamps can be driven by radio-frequency signals in the ISM frequency band at 2.45 GHz, using a matching network to transform the impedance of the plasma to the source impedance. To achieve an optimal operating condition, a good characterization of the lamp in terms of radio frequency equivalent circuits under operating conditions is necessary, enabling the design of an efficient matching network. This paper presents the characterization technique for such lamps and presents the design of the required matching network. For the characterization, a high-intensity discharge lamp was driven by a monofrequent large signal at 2.45 GHz, whereas a frequency sweep over 300 MHz was performed across this signal to measure so-called small-signal hot S-parameters using a vector network analyzer. These parameters are then used as an equivalent load in a circuit simulator to design an appropriate matching network. Using the measured data as a black-box model in the simulation results in a quick and efficient method to simulate and design efficient matching networks in spite of the complex plasma behavior. Furthermore, photometric analysis of high-intensity discharge lamps are carried out, comparing microwave operation to conventional operation. Y1 - 2014 U6 - https://doi.org/10.1109/TMTT.2014.2342652 SN - 0018-9480 VL - 62 IS - 10 SP - 2471 EP - 2480 PB - IEEE CY - New York ER - TY - JOUR A1 - Khaydukova, M. M. A1 - Zadorozhnaya, O. A. A1 - Kirsanov, D. O. A1 - Iken, Heiko A1 - Rolka, David A1 - Schöning, Michael Josef A1 - Babain, V. A. A1 - Vlasov, Yu. G. A1 - Legin, A. V. T1 - Multivariate processing of atomic-force microscopy images for detection of the response of plasticized polymeric membranes JF - Russian journal of applied chemistry N2 - The possibility of using the atomic-force microscopy as a method for detection of the analytical signal from plasticized polymeric sensor membranes was analyzed. The surfaces of cadmium-selective membranes based on two polymeric matrices were examined. The digital images were processed with multivariate image analysis techniques. A correlation was found between the surface profile of an ion-selective membrane and the concentration of the ion in solution. Y1 - 2014 U6 - https://doi.org/10.1134/S1070427214030112 SN - 1608-3296 (E-Journal); 1070-4272 (Print) VL - 87 IS - 3 SP - 307 EP - 314 PB - Springer CY - Dordrecht ER - TY - JOUR A1 - Reisert, Steffen A1 - Geissler, H. A1 - Weiler, C. A1 - Wagner, P. A1 - Schöning, Michael Josef T1 - Multiple sensor-type system for monitoring the microbicidal effectiveness of aseptic sterilisation processes JF - Food control N2 - The present work describes a novel multiple sensor-type system for the real-time analysis of aseptic sterilisation processes employing gaseous hydrogen peroxide (H2O2) as a sterilant. The inactivation kinetics of Bacillus atrophaeus by gaseous H2O2 have been investigated by means of a methodical calibration experiment, taking into account the process variables H2O2 concentration, humidity and gas temperature. It has been found that the microbicidal effectiveness at H2O2 concentrations above 2% v/v is largely determined by the concentration itself, while at lower H2O2 concentrations, the gas temperature and humidity play a leading role. Furthermore, the responses of different types of gas sensors towards the influencing factors of the sterilisation process have been analysed within the same experiment. Based on a correlation established between the inactivation kinetics and the sensor responses, a calorimetric H2O2 sensor and a metal-oxide semiconductor (MOX) sensor have been identified as possible candidates for monitoring the microbicidal effectiveness of aseptic sterilisation processes employing gaseous H2O2. Therefore, two linear models that describe the relationship between sensor response and microbicidal effectiveness have been proposed. Y1 - 2015 U6 - https://doi.org/10.1016/j.foodcont.2014.07.063 SN - 1873-7129 (E-Journal); 0956-7135 (Print) VL - 47 SP - 615 EP - 622 ER - TY - JOUR A1 - Guo, Yuanyuan A1 - Miyamoto, Ko-ichiro A1 - Wagner, Torsten A1 - Schöning, Michael Josef A1 - Yoshinobu, Tatsuo T1 - Device simulation of the light-addressable potentiometric sensor for the investigation of the spatial resolution JF - Sensors and actuators B: Chemical N2 - As a semiconductor-based electrochemical sensor, the light-addressable potentiometric sensor (LAPS) can realize two dimensional visualization of (bio-)chemical reactions at the sensor surface addressed by localized illumination. Thanks to this imaging capability, various applications in biochemical and biomedical fields are expected, for which the spatial resolution is critically significant. In this study, therefore, the spatial resolution of the LAPS was investigated in detail based on the device simulation. By calculating the spatiotemporal change of the distributions of electrons and holes inside the semiconductor layer in response to a modulated illumination, the photocurrent response as well as the spatial resolution was obtained as a function of various parameters such as the thickness of the Si substrate, the doping concentration, the wavelength and the intensity of illumination. The simulation results verified that both thinning the semiconductor substrate and increasing the doping concentration could improve the spatial resolution, which were in good agreement with known experimental results and theoretical analysis. More importantly, new findings of interests were also obtained. As for the dependence on the wavelength of illumination, it was found that the known dependence was not always the case. When the Si substrate was thick, a longer wavelength resulted in a higher spatial resolution which was known by experiments. When the Si substrate was thin, however, a longer wavelength of light resulted in a lower spatial resolution. This finding was explained as an effect of raised concentration of carriers, which reduced the thickness of the space charge region. The device simulation was found to be helpful to understand the relationship between the spatial resolution and device parameters, to understand the physics behind it, and to optimize the device structure and measurement conditions for realizing higher performance of chemical imaging systems. Y1 - 2014 U6 - https://doi.org/10.1016/j.snb.2014.08.016 SN - 1873-3077 (E-Journal); 0925-4005 (Print) VL - 204 SP - 659 EP - 665 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Alhwarin, Faraj A1 - Ferrein, Alexander A1 - Scholl, Ingrid T1 - IR stereo kinect: improving depth images by combining structured light with IR stereo Y1 - 2014 SP - 1 EP - 9 ER - TY - JOUR A1 - Frotscher, Ralf A1 - Staat, Manfred T1 - Stresses produced by different textile mesh implants in a tissue equivalent JF - BioNanoMaterials N2 - Two single-incision mini-slings used for treating urinary incontinence in women are compared with respect to the stresses they produce in their surrounding tissue. In an earlier paper we experimentally observed that these implants produce considerably different stress distributions in a muscle tissue equivalent. Here we perform 2D finite element analyses to compare the shear stresses and normal stresses in the tissue equivalent for the two meshes and to investigate their failure behavior. The results clearly show that the Gynecare TVT fails for increasing loads in a zipper-like manner because it gradually debonds from the surrounding tissue. Contrary to that, the tissue at the ends of the DynaMesh-SIS direct may rupture but only at higher loads. The simulation results are in good agreement with the experimental observations thus the computational model helps to interpret the experimental results and provides a tool for qualitative evaluation of mesh implants. Y1 - 2014 U6 - https://doi.org/10.1515/bnm-2014-0003 SN - 2191-4672 (E-Journal); 2193-066X (E-Journal); 0011-8656 (Print); 1616-0177 (Print); 2193-0651 (Print) VL - 15 IS - 1-2 SP - 25 EP - 30 PB - De Gruyter CY - Berlin ER - TY - JOUR A1 - Glaser, Markus A1 - Schmitz, Philipp T1 - Privatanleger am Optionsscheinmarkt Y1 - 2006 SP - 1 EP - 46 ER - TY - JOUR A1 - Glaser, Markus A1 - Schmitz, Philipp T1 - Privatanleger am Optionsscheinmarkt JF - Zeitschrift für Bankrecht und Bankwirtschaft : ZBB Y1 - 2007 SN - 0936-2800 N1 - Printausg. in der Bibliothek Eupener Str. vorhanden VL - Jg. 19 IS - H. 3 SP - 214 EP - 230 ER - TY - JOUR A1 - Schmitz, Philipp A1 - Weber, Martin T1 - Buying and selling behavior of individual investors in option-like securities Y1 - 2007 SP - 1 EP - 36 ER - TY - JOUR A1 - Schmitz, Philipp A1 - Weber, Martin T1 - Buying and selling behavior of individual investors in option-like securities JF - Die Betriebswirtschaft : DBW N2 - We analyze the trading behavior of individual investors in option-like securities, namely bankissued warrants, and thus expand the growing literature of investors behavior to a new kind of securities. A unique data set from a large German discount broker gives us the opportunity to analyze the trading behavior of 1,454 investors, making 89,958 transactions in 6,724 warrants on 397 underlyings. In different logit regression, we make use of the facts that investors can speculate on rising and falling prices of the underlying with call and put warrants and that we also have information about the stock portfolios of the investors. We report several facts about the trading behavior of individual investors in warrants that are consistent with the literature on the behavior of individual investors in the stock market. The warrant investors buy calls and sell puts if the price of the underlying has decreased over the past trading days and they sell calls and buy puts if the price of the underlying has increased. That means, the investors follow negative feedback trading strategies in all four trading categories observed. In addition, we find strong evidence for the disposition effect for call as well as put warrants, which is reversed in December. The trading behavior is also influenced if the underlying reaches some exceptionally prices, e.g. highs, lows or the strike price. We show that hedging, as one natural candidate to buy puts, does not play an important role in the market for bank-issued warrants. KW - Bank-issued Warrants KW - Disposition Effect KW - Negative Feedback Trading KW - Trading Behavior KW - Individual Investors Y1 - 2012 U6 - https://doi.org/10.2139/ssrn.2055088 SN - 0342-7064 VL - 72 IS - 5 SP - 409 EP - 426 PB - Schäffer-Poeschel CY - Stuttgart ER - TY - JOUR A1 - Vieira da Silva, Maria Eugenia A1 - Schwarzer, Klemens A1 - Hoffschmidt, Bernhard A1 - Pinheiro Rodrigues, Frederico A1 - Schwarzer, Tarik A1 - Costa Rocha, Paulo Alexandre T1 - Mass transfer correlation for evaporation–condensation thermal process in the range of 70 °C–95 °C JF - Renewable energy Y1 - 2013 SN - 1879-0682 (E-Journal); 0960-1481 (Print) VL - Vol. 53 SP - 174 EP - 179 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Pohl, Martina A1 - Siegert, Petra A1 - Mesch, K. A1 - Bruhn, H. A1 - Grötzinger, Joachim T1 - Active site mutants of pyruvate decarboxylase from Zymomonas mobilis : a site-directed mutagenesis study of L112, I472, I476, E473 and N482 JF - European journal of biochemistry Y1 - 1998 SN - 1432-1033 (E-Journal); 1742-4658 (E-Journal); 0014-2956 (Print); 1742-464X (Print) VL - Vol. 257 IS - Iss. 3 SP - 538 EP - 546 ER - TY - JOUR A1 - Iding, Hans A1 - Siegert, Petra A1 - Mesch, K. A1 - Pohl, Martina T1 - Application of α-keto acid decarboxylases in biotransformations JF - Biochimica et biophysica acta (BBA) - Protein structure and molecular enzymology Y1 - 1998 SN - 1879-2588 (E-Journal); 0167-4838 (Print) VL - Vol. 1385 IS - Iss. 2 SP - 307 EP - 322 ER - TY - JOUR A1 - Iding, Hans A1 - Dünnwald, Thomas A1 - Greiner, Lasse A1 - Liese, Andreas A1 - Müller, Michael A1 - Siegert, Petra A1 - Grötzinger, Joachim A1 - Demir, Ayhan S. A1 - Pohl, Martina T1 - Benzoylformate Decarboxylase from Pseudomonas putida as Stable Catalyst for the Synthesis of Chiral 2-Hydroxy Ketones JF - Chemistry - a European journal Y1 - 2000 SN - 1521-3765 (E-Journal); 0947-6539 (Print) VL - Vol. 6 IS - Iss. 8 SP - 1483 EP - 1495 ER - TY - JOUR A1 - Dünnwald, Thomas A1 - Demir, Ayhan S. A1 - Siegert, Petra A1 - Pohl, Martina A1 - Müller, Michael T1 - Enantioselective Synthesis of (S)-2-Hydroxypropanone Derivatives by Benzoylformate Decarboxylase Catalyzed C−C Bond Formation JF - European journal of organic chemistry Y1 - 2000 SN - 0365-5490 (E-Journal); 1099-0690 (E-Journal); 0075-4617 (Print); 0170-2041 (Print); 0947-3440 (Print); 1434-193X (Print); 1434-243X (Print) VL - Vol. 2000 IS - Iss. 11 SP - 2161 EP - 2170 ER - TY - JOUR A1 - Dünnwald, Thomas A1 - Demir, Ayhan S. A1 - Siegert, Petra A1 - Pohl, Martina A1 - Müller, Michael T1 - ChemInform Abstract: Enantioselective synthesis of (S)-2-Hydroxypropanone derivatives by Benzoylformate Decarboxylase Catalyzed C—C Bond Formation JF - Cheminform Y1 - 2001 SN - 1522-2667 (E-Journal); 0931-7597 (Print) VL - Vol. 32 IS - Iss. 4 SP - Publ. online ER - TY - JOUR A1 - Dünkelmann, Pascal A1 - Kolter-Jung, Doris A1 - Nitsche, Adam A1 - Demir, Ayhan S. A1 - Siegert, Petra A1 - Lingen, Bettina A1 - Baumann, Martin A1 - Pohl, Martina A1 - Müller, Michael T1 - Development of a donor-acceptor concept for enzymatic cross-coupling reactions of adehydes : the first asymmetric cross-benzoin condensation JF - Journal of the American Chemical Society Y1 - 2002 SN - 1520-5126 (E-Journal); 0002-7863 (Print) VL - Vol. 124 SP - 12084 EP - 12085 ER - TY - JOUR A1 - Siegert, Petra A1 - McLeish, Michael J. A1 - Baumann, Martin A1 - Iding, Hans A1 - Kneen, Malea M. A1 - Kenyon, George L. A1 - Pohl, Martina T1 - Exchanging the substrate specificities of pyruvate decarboxylase from Zymomonas mobilis and benzoylformate decarboxylase from Pseudomonas putida JF - Protein engineering, design, and selection : peds Y1 - 2005 SN - 1460-213X (E-Journal); 1741-0134 (E-Journal); 0269-2139 (Print); 1741-0126 (Print) VL - Vol. 18 IS - Iss. 7 SP - 345 EP - 357 ER - TY - JOUR A1 - Ribitsch, D. A1 - Karl, W. A1 - Birner-Gruenberger, R. A1 - Gruber, K. A1 - Eiteljoerg, I. A1 - Remler, P. A1 - Wieland, S. A1 - Siegert, Petra A1 - Maurer, Karl-Heinz A1 - Schwab, H. T1 - C-terminal truncation of a metagenome-derived detergent protease for effective expression in E. coli JF - Journal of biotechnology N2 - Recently, a new alkaline protease named HP70 showing highest homology to extracellular serine proteases of Stenotrophomonas maltophilia and Xanthomonas campestris was found in the course of a metagenome screening for detergent proteases (Niehaus et al., submitted for publication). Attempts to efficiently express the enzyme in common expression hosts had failed. This study reports on the realization of overexpression in Escherichia coli after structural modification of HP70. Modelling of HP70 resulted in a two-domain structure, comprising the catalytic domain and a C-terminal domain which includes about 100 amino acids. On the basis of the modelled structure the enzyme was truncated by deletion of most of the C-terminal domain yielding HP70-C477. This structural modification allowed effective expression of active enzyme using E. coli BL21-Gold as the host. Specific activity of HP70-C477 determined with suc-l-Ala-l-Ala-l-Pro-l-Phe-p-nitroanilide as the substrate was 30 ± 5 U/mg compared to 8 ± 1 U/mg of the native enzyme. HP70-C477 was most active at 40 °C and pH 7–11; these conditions are prerequisite for a potential application as detergent enzyme. Determination of kinetic parameters at 40 °C and pH = 9.5 resulted in KM = 0.23 ± 0.01 mM and kcat = 167.5 ± 3.6 s⁻¹. MS-analysis of peptide fragments obtained from incubation of HP70 and HP70-C477 with insulin B indicated that the C-terminal domain influences the cleavage preferences of the enzyme. Washing experiments confirmed the high potential of HP70-C477 as detergent protease. Y1 - 2010 U6 - https://doi.org/10.1016/j.jbiotec.2010.09.947 SN - 1873-4863 (E-Journal); 0168-1656 (Print) VL - 150 IS - 3 SP - 408 EP - 416 PB - Elsevier CY - Amsterdam ER -