TY - JOUR A1 - Oberländer, Jan A1 - Kirchner, Patrick A1 - Boyen, Hans-Gerd A1 - Schöning, Michael Josef T1 - Detection of hydrogen peroxide vapor by use of manganese(IV) oxide as catalyst for calorimetric gas sensors JF - Physica status solidi A: Applications and materials science N2 - In this work, the catalyst manganese(IV) oxide (MnO2), of calorimetric gas sensors (to monitor the sterilization agent vaporized hydrogen peroxide) has been investigated in more detail. Chemical analyses by means of X-ray-induced photoelectron spectroscopy have been performed to unravel the surface chemistry prior and after exposure to hydrogen peroxide vapor at elevated temperature, as applied in the sterilization processes of beverage cartons. The surface characterization reveals a change in oxidation states of the metal oxide catalyst after exposure to hydrogen peroxide. Additionally, a cleaning effect of the catalyst, which itself is attached to the sensor surface by means of a polymer interlayer, could be observed. Y1 - 2014 U6 - https://doi.org/10.1002/pssa.201330359 SN - 1521-396X (E-Journal); 1862-6319 (E-Journal); 0031-8965 (Print); 1862-6300 (Print) VL - 211 IS - 6 SP - 1372 EP - 1376 PB - Wiley-VCH CY - Weinheim ER - TY - JOUR A1 - Fuest, Matthias A1 - Kotliar, Konstantin A1 - Walter, Peter A1 - Plange, Niklas T1 - Monitoring intraocular pressure changes after intravitreal Ranibizumab injection using rebound tonometry JF - Ophthalmic and physiological optics Y1 - 2014 U6 - https://doi.org/10.1111/opo.12134 SN - 1475-1313 (E-Journal); 0275-5408 (Print) N1 - Special Issue: The Ageing Visual System VL - 34 IS - 4 SP - 438 EP - 444 PB - Wiley-Blackwell CY - Oxford ER - TY - JOUR A1 - Guo, Yuanyuan A1 - Miyamoto, Ko-ichiro A1 - Wagner, Torsten A1 - Schöning, Michael Josef A1 - Yoshinobu, Tatsuo T1 - Theoretical study and simulation of light-addressable potentiometric sensors JF - Physica status solidi (A) : applications and materials N2 - The light-addressable potentiometric sensor (LAPS) is a semiconductor-based potentiometric sensor using a light probe with an ability of detecting the concentration of biochemical species in a spatially resolved manner. As an important biomedical sensor, research has been conducted to improve its performance, for instance, to realize high-speed measurement. In this work, the idea of facilitating the device-level simulation, instead of using an equivalent-circuit model, is presented for detailed analysis and optimization of the performance of the LAPS. Both carrier distribution and photocurrent response have been simulated to provide new insight into both amplitude-mode and phase-mode operations of the LAPS. Various device parameters can be examined to effectively design and optimize the LAPS structures and setups for enhanced performance. Y1 - 2014 U6 - https://doi.org/10.1002/pssa.201330354 SN - 0031-8965 VL - 211 IS - 6 SP - 1467 EP - 1472 PB - Wiley-VCH CY - Weinheim ER - TY - JOUR A1 - Smith, Walker O. A1 - Baumann, Marcus A1 - Wilson, David L. A1 - Aletsee, Ludwig T1 - Phytoplankton biomass and productivity in the marginal ice zone of the Fram Strait during summer 1984 JF - Journal of geophysical research Y1 - 1987 SN - 2156-2202 (E-Journal); 2169-9291 (E-Journal); 0148-0227 (Print); 2169-9275 (Print) VL - Vol. 92 IS - Iss. C7 SP - 6777 EP - 6786 ER - TY - JOUR A1 - Jahnke, J. A1 - Baumann, Marcus T1 - Differentiation between Phaeocystis pouchetii (Har.) Lagerheim and Phaeocystis globosa Scherffel JF - Hydrobiological bulletin Y1 - 1987 SN - 0165-1404 (Print); 1573-5125 (E-Journal) VL - Vol. 21 IS - Iss. 2 SP - 141 EP - 147 ER - TY - JOUR A1 - Aletsee, Ludwig A1 - Baumann, Marcus T1 - A laboratory incubator equipped with facilities to automatically simulate natural irradiance JF - Boletim do Instituto Oceanográfico / Universidade de São Paulo Y1 - 1991 SN - 1982-436X; 0080-6331 VL - Vol. 39 IS - No. 2 SP - 155 EP - 159 ER - TY - JOUR A1 - Tüg, Helmut A1 - Baumann, Marcus T1 - Problems of UV-B radiation measurements in biological research : critical remarks on current techniques and suggestions for improvements JF - Geophysical research letters Y1 - 1994 SN - 1944-8007 (E-Journal); 0094-8276 (Print) VL - Vol. 21 IS - Iss. 8 SP - 689 EP - 692 ER - TY - JOUR A1 - Medlin, L. K. A1 - Lange, M. A1 - Baumann, Marcus T1 - Genetic differentiation among three colony-forming species of Phaeocystis : further evidence for the phylogeny of the Prymnesiophyta JF - Phycologia Y1 - 1994 SN - 0031-8884 VL - Vol. 33 IS - Iss. 3 SP - 199 EP - 212 ER - TY - JOUR A1 - Tüg, Helmut A1 - Baumann, Marcus T1 - Reply to the comments by R.L. McKenzie and P.V. Johnston on our paper “Problems of UV-B radiation measurements in biological research: Critical Remarks on current techniques and suggestions for improvements” JF - Geophysical research letters Y1 - 1995 SN - 1944-8007 (E-Journal); 0094-8276 (Print) VL - Vol. 22 IS - Iss. 9 SP - 1159 EP - 1160 ER - TY - JOUR A1 - Schirra, Julian A1 - Watmuff, Jonathan A1 - Bauschat, J.-Michael T1 - Highly non-planar lifting systems: a relative assessment of existing potential-methodologies to accurately estimate the induced drag JF - 32nd AIAA Applied Aerodynamics Conference 2014 : June, 16-20 2014, Atlanta, Ga. Y1 - 2014 SN - 978-1-62410-288-2 U6 - https://doi.org/10.2514/6.2014-2988 SP - Publ. online ER - TY - JOUR A1 - Riedel, Marc A1 - Kartchemnik, Julia A1 - Schöning, Michael Josef A1 - Lisdat, Fred T1 - Impedimetric DNA detection – steps forward to sensorial application JF - Analytical chemistry N2 - This study describes a label-free impedimetric sensor based on short ssDNA recognition elements for the detection of hybridization events. We concentrate on the elucidation of the influence of target length and recognition sequence position on the sensorial performance. The impedimetric measurements are performed in the presence of the redox system ferri-/ferrocyanide and show an increase in charge transfer resistance upon hybridization of ssDNA to the sensor surface. Investigations on the impedimetric signal stability demonstrate a clear influence of the buffers used during the sensor preparation and the choice of the passivating mercaptoalcanol compound. A stable sensor system has been developed, enabling a reproducible detection of 25mer target DNA in the low nanomolar range. After hybridization, a sensor regeneration can be reached with deionized water by adjustment of effective convection conditions, ensuring a sensor reusability. By investigations of longer targets with overhangs exposed to the solution, we can demonstrate applicability of the impedimetric detection for longer ssDNA. However, a decreasing charge transfer resistance change (ΔRct) is found by extending the overhang. As a strategy to increase the impedance change for longer target strands, the position of the recognition sequence can be designed in a way that a small overhang is exposed to the electrode surface. This is found to result in an increase in the relative Rct change. These results suggest that DNA and consequently negative charge near the electrode possess a larger impact on the impedimetric signal than DNA further away. Y1 - 2014 U6 - https://doi.org/10.1021/ac501800q SN - 1520-6882 (E-Journal); 0003-2700 (Print); 0096-4484 (Print) VL - 86 (2014) IS - 15 SP - 7867 EP - 7874 PB - ACS Publications CY - Columbus ER - TY - JOUR A1 - Martinez, Ronny A1 - Jakob, Felix A1 - Tu, Ran A1 - Siegert, Petra A1 - Maurer, Karl-Heinz A1 - Schwaneberg, Ulrich T1 - Increasing activity and thermal resistance of Bacillus gibsonii alkaline protease (BgAP) by directed evolution JF - Biotechnology and bioengineering Y1 - 2013 SN - 1097-0290 (E-Journal); 0006-3592 (Print); 0368-1467 (Print) VL - Vol. 110 IS - Iss. 3 SP - 711 EP - 720 PB - Wiley CY - Weinheim ER - TY - JOUR A1 - Jakob, Felix A1 - Martinez, Ronny A1 - Mandawe, John A1 - Hellmuth, Hendrik A1 - Siegert, Petra A1 - Maurer, Karl-Heinz A1 - Schwaneberg, Ulrich T1 - Surface charge engineering of a Bacillus gibsonii subtilisin protease JF - Applied microbiology and biotechnology Y1 - 2013 SN - 1432-0614 (E-Journal); 0171-1741 (Print); 0175-7598 (Print); 0340-2118 (Print) VL - Vol. 97 IS - Iss. 15 SP - 6793 EP - 6802 PB - Springer CY - Berlin ER - TY - JOUR A1 - Niehaus, F. A1 - Gabor, E. A1 - Wieland, S. A1 - Siegert, Petra A1 - Maurer, Karl-Heinz A1 - Eck, J. T1 - Enzymes for the laundry industries: tapping the vast metagenomic pool of alkaline proteases JF - Microbial biotechnology Y1 - 2011 SN - 1432-0614 (E-Journal); 0171-1741 (Print); 0175-7598 (Print); 0340-2118 (Print) VL - Vol. 4 IS - Iss. 6 SP - 767 EP - 776 PB - Springer CY - Berlin ER - TY - JOUR A1 - Ribitsch, D. A1 - Heumann, S. A1 - Karl, W. A1 - Gerlach, J. A1 - Leber, R. A1 - Birner-Gruenberger, R. A1 - Gruber, K. A1 - Eiteljoerg, I. A1 - Remler, P. A1 - Siegert, Petra A1 - Lange, J. A1 - Maurer, Karl-Heinz A1 - Berg, G. A1 - Guebitz, G. M. A1 - Schwab, H. T1 - Extracellular serine proteases from Stenotrophomonas maltophilia: Screening, isolation and heterologous expression in E. coli JF - Journal of biotechnology N2 - A large strain collection comprising antagonistic bacteria was screened for novel detergent proteases. Several strains displayed protease activity on agar plates containing skim milk but were inactive in liquid media. Encapsulation of cells in alginate beads induced protease production. Stenotrophomonas maltophilia emerged as best performer under washing conditions. For identification of wash-active proteases, four extracellular serine proteases called StmPr1, StmPr2, StmPr3 and StmPr4 were cloned. StmPr2 and StmPr4 were sufficiently overexpressed in E. coli. Expression of StmPr1 and StmPr3 resulted in unprocessed, insoluble protein. Truncation of most of the C-terminal domain which has been identified by enzyme modeling succeeded in expression of soluble, active StmPr1 but failed in case of StmPr3. From laundry application tests StmPr2 turned out to be a highly wash-active protease at 45 °C. Specific activity of StmPr2 determined with suc-l-Ala-l-Ala-l-Pro-l-Phe-p-nitroanilide as the substrate was 17 ± 2 U/mg. In addition we determined the kinetic parameters and cleavage preferences of protease StmPr2. KW - Alginate beads KW - Stenotrophomonas maltophilia KW - Detergent protease Y1 - 2012 U6 - https://doi.org/10.1016/j.jbiotec.2011.09.025 SN - 1873-4863 (E-Journal); 0168-1656 (Print) VL - 157 IS - 1 SP - 140 EP - 147 PB - Elsevier CY - Amsterdam 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 - 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 - Ribitsch, D. A1 - Heumann, S. A1 - Trotscha, E. A1 - Herrero Acero, E. A1 - Greimel, K. A1 - Leber, R. A1 - Birger-Gruenberger, R. A1 - Deller, S. A1 - Eiteljoerg, I. A1 - Remler, P. A1 - Weber, Th. A1 - Siegert, Petra A1 - Maurer, Karl-Heinz A1 - Donelli, I. A1 - Freddi, G. A1 - Schwab, H. A1 - Guebitz, G. M. T1 - Hydrolysis of polyethyleneterephthalate by p-nitrobenzylesterase from Bacillus subtilis JF - Biotechnology progress Y1 - 2011 SN - 1520-6033 (E-Journal); 8756-7938 (Print) VL - Vol. 27 IS - Iss. 4 SP - 951 EP - 960 PB - Wiley CY - Hoboken 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 - 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 -