TY  - JOUR
A1  - Borgmeier, Claudia
A1  - Bongaerts, Johannes
A1  - Meinhardt, Friedhelm
T1  - Genetic analysis of the Bacillus licheniformis degSU operon and the impact of regulatory mutations on protease production
JF  - Journal of biotechnology
N2  - Disruption experiments targeted at the Bacillus licheniformis degSU operon and GFP-reporter analysis provided evidence for promoter activity immediately upstream of degU. pMutin mediated concomitant introduction of the degU32 allele – known to cause hypersecretion in Bacillus subtilis – resulted in a marked increase in protease activity. Application of 5-fluorouracil based counterselection through establishment of a phosphoribosyltransferase deficient Δupp strain eventually facilitated the marker-free introduction of degU32 leading to further protease enhancement achieving levels as for hypersecreting wild strains in which degU was overexpressed. Surprisingly, deletion of rapG – known to interfere with DegU DNA-binding in B. subtilis – did not enhance protease production neither in the wild type nor in the degU32 strain. The combination of degU32 and Δupp counterselection in the type strain is not only equally effective as in hypersecreting wild strains with respect to protease production but furthermore facilitates genetic strain improvement aiming at biological containment and effectiveness of biotechnological processes.
KW  - Marker-free mutagenesis
KW  - Extracellular enzymes
KW  - Uracil-phosphoribosyltransferase
KW  - Hypersecretion
Y1  - 2012
U6  - https://doi.org/10.1016/j.jbiotec.2012.02.011
SN  - 1873-4863 (E-Journal); 0168-1656 (Print)
VL  - 159
IS  - 1-2
SP  - 12
EP  - 20
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Hasan, Istabrak
A1  - Keil, Ludger
A1  - Staat, Manfred
A1  - Wahl, Gerhard
A1  - Bourauel, Christoph
T1  - Determination of the frictional coefficient of the implant-antler interface : experimental approach
JF  - Biomedical Engineering / Biomedizinische Technik
N2  - The similar bone structure of reindeer antler to human bone permits studying the osseointegration of dental implants in the jawbone. As the friction is one of the major factors that have a significant influence on the initial stability of immediately loaded dental implants, it is essential to define the frictional coefficient of the implant-antler interface. In this study, the kinetic frictional forces at the implant-antler interface were measured experimentally using an optomechanical setup and a stepping motor controller under different axial loads and sliding velocities. The corresponding mean values of the static and kinetic frictional coefficients were within the range of 0.5–0.7 and 0.3–0.5, respectively. An increase in the frictional forces with increasing applied axial loads was registered. The measurements showed an evidence of a decrease in the magnitude of the frictional coefficient with increasing sliding velocity. The results of this study provide a considerable assessment to clarify the suitable frictional coefficient to be used in the finite element contact analysis of antler specimens.
Y1  - 2012
SN  - 1862-278X
VL  - 57
IS  - 5
SP  - 359
EP  - 363
PB  - De Gruyter
CY  - Berlin
ER  - 
TY  - JOUR
A1  - Poghossian, Arshak
A1  - Weil, M. H.
A1  - Bäcker, Matthias
A1  - Mayer, D.
A1  - Schöning, Michael Josef
T1  - Field-effect Devices Functionalised with Gold-Nanoparticle/Macromolecule Hybrids: New Opportunities for a Label-Free Biosensing
JF  - Procedia Engineering
N2  - Field-effect capacitive electrolyte-insulator-semiconductor (EIS) sensors functionalised with citrate-capped gold nanoparticles (AuNP) have been used for the electrostatic detection of macromolecules by their intrinsic molecular charge. The EIS sensor detects the charge changes in the AuNP/macromolecule hybrids induced by the adsorption or binding events. A feasibility of the proposed detection scheme has been exemplary demonstrated by realising EIS sensors for the detection of poly-D-lysine molecules.
Y1  - 2012
U6  - https://doi.org/10.1016/j.proeng.2012.09.136
SN  - 1877-7058
N1  - Part of special issue "26th European Conference on Solid-State Transducers, EUROSENSOR 2012"
IS  - 47
SP  - 273
EP  - 276
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Weigand, Christoph
T1  - Statistical Tests Based on Reliability and Precision
JF  - Economic Quality Control : EQC ; international journal for quality and reliability
N2  - The construction of a statistical test is investigated which is based only on “reliability” and “precision” as quality criteria. The reliability of a statistical test is quantifiedin a straightforward way by the probability that the decision of the test is correct.  However, the quantification of the precision of a statistical test is not at all evident.  Thereforethe paper presents and discusses several approaches.  Moreover the distinction of “nullhypothesis” and “alternative hypothesis” is not necessary any longer.
Y1  - 2012
U6  - https://doi.org/10.1515/eqc-2012-0002
SN  - 1869-6147
VL  - 27
IS  - 1
SP  - 43
EP  - 64
PB  - De Gruyter
CY  - Berlin
ER  - 
TY  - JOUR
A1  - Schusser, Sebastian
A1  - Poghossian, Arshak
A1  - Bäcker, Matthias
A1  - Leinhos, Marcel
A1  - Wagner, Patrick
A1  - Schöning, Michael Josef
T1  - Characterization of biodegradable polymers with capacitive field-effect sensors
JF  - Sensors and actuators B: Chemical
N2  - In vitro studies of the degradation kinetic of biopolymers are essential for the design and optimization of implantable biomedical devices. In the presented work, a field-effect capacitive sensor has been applied for the real-time and in situ monitoring of degradation processes of biopolymers for the first time. The polymer-covered field-effect sensor is, in principle, capable to detect any changes in bulk, surface and interface properties of the polymer induced by degradation processes. The feasibility of this approach has been experimentally proven by using the commercially available biomedical polymer poly(D,L-lactic acid) (PDLLA) as a model system. PDLLA films of different thicknesses were deposited on the Ta₂O₅-gate surface of the field-effect structure from a polymer solution by means of spin-coating method. The polymer-modified field-effect sensors have been characterized by means of capacitance–voltage and impedance-spectroscopy method. The degradation of the PDLLA was accelerated by changing the degradation medium from neutral (pH 7.2) to alkaline (pH 9) condition, resulting in drastic changes in the capacitance and impedance spectra of the polymer-modified field-effect sensor.
KW  - Impedance spectroscopy
KW  - C–V method
KW  - Real-time monitoring
KW  - Poly(d,l-lacticacid)
KW  - (Bio)degradation
KW  - Field-effect sensor
Y1  - 2012
U6  - https://doi.org/10.1016/j.snb.2012.07.099
SN  - 0925-4005
N1  - Part of special issue "Selected Papers from the 14th International Meeting on Chemical Sensors"
VL  - 187
SP  - 2
EP  - 7
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Bäcker, Matthias
A1  - Raue, Markus
A1  - Schusser, Sebastian
A1  - Jeitner, C.
A1  - Breuer, L.
A1  - Wagner, P.
A1  - Poghossian, Arshak
A1  - Förster, Arnold
A1  - Mang, Thomas
A1  - Schöning, Michael Josef
T1  - Microfluidic chip with integrated microvalves based on temperature- and pH-responsive hydrogel thin films
JF  - Physica Status Solidi  (a)
N2  - Two types of microvalves based on temperature-responsive poly(N-isopropylacrylamide) (PNIPAAm) and pH-responsive poly(sodium acrylate) (PSA) hydrogel films have been developed and tested. The PNIPAAm and PSA hydrogel films were prepared by means of in situ photopolymerization directly inside the fluidic channel of a microfluidic chip fabricated by combining Si and SU-8 technologies. The swelling/shrinking properties and height changes of the PNIPAAm and PSA films inside the fluidic channel were studied at temperatures of deionized water from 14 to 36 °C and different pH values (pH 3–12) of Titrisol buffer, respectively. Additionally, in separate experiments, the lower critical solution temperature (LCST) of the PNIPAAm hydrogel was investigated by means of a differential scanning calorimetry (DSC) and a surface plasmon resonance (SPR) method. Mass-flow measurements have shown the feasibility of the prepared hydrogel films to work as an on-chip integrated temperature- or pH-responsive microvalve capable to switch the flow channel on/off.
Y1  - 2012
U6  - https://doi.org/10.1002/pssa.201100763
SN  - 1862-6319
VL  - 209
IS  - 5
SP  - 839
EP  - 845
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Schiffer, Stefan
A1  - Ferrein, Alexander
A1  - Lakemeyer, Gerhard
T1  - Caesar: an intelligent domestic service robot
JF  - Intelligent service robotics
N2  - In this paper we present CAESAR, an intelligent domestic service robot. In domestic settings for service robots complex tasks have to be accomplished. Those tasks benefit from deliberation, from robust action execution and from flexible methods for human–robot interaction that account for qualitative notions used in natural language as well as human fallibility. Our robot CAESAR deploys AI techniques on several levels of its system architecture. On the low-level side, system modules for localization or navigation make, for instance, use of path-planning methods, heuristic search, and Bayesian filters. For face recognition and human–machine interaction, random trees and well-known methods from natural language processing are deployed. For deliberation, we use the robot programming and plan language READYLOG, which was developed for the high-level control of agents and robots; it allows combining programming the behaviour using planning to find a course of action. READYLOG is a variant of the robot programming language Golog. We extended READYLOG to be able to cope with qualitative notions of space frequently used by humans, such as “near” and “far”. This facilitates human–robot interaction by bridging the gap between human natural language and the numerical values needed by the robot. Further, we use READYLOG to increase the flexible interpretation of human commands with decision-theoretic planning. We give an overview of the different methods deployed in CAESAR and show the applicability of a system equipped with these AI techniques in domestic service robotics
Y1  - 2012
U6  - https://doi.org/10.1007/s11370-012-0118-y
SN  - 1861-2776
N1  - Special Issue on Artificial Intelligence Techniques for Robotics: Sensing, Representation and Action, Part I
VL  - 5
IS  - 4
SP  - 259
EP  - 276
PB  - Springer
CY  - Berlin
ER  - 
TY  - JOUR
A1  - Becker, Jörg
A1  - Delfmann, Patrick
A1  - Eggert, Mathias
A1  - Schwittay, Sebastian
T1  - Generalizability and Applicability of Model-Based Business Process Compliance-Checking Approaches — A State-of-the-Art Analysis and Research Roadmap
JF  - Business Research : BuR
N2  - With a steady increase of regulatory requirements for business processes, automation support of compliance management is a field garnering increasing attention in Information Systems research. Several approaches have been developed to support compliance checking of process models. One major challenge for such approaches is their ability to handle different modeling techniques and compliance rules in order to enable widespread adoption and application. Applying a structured literature search strategy, we reflect and discuss compliance-checking approaches in order to provide an insight into their generalizability and evaluation. The results imply that current approaches mainly focus on special modeling techniques and/or a restricted set of types of compliance rules. Most approaches abstain from real-world evaluation which raises the question of their practical applicability. Referring to the search results, we propose a roadmap for further research in model-based business process compliance checking.
Y1  - 2012
U6  - https://doi.org/10.1007/BF03342739
SN  - 1866-8658
VL  - 5
IS  - 2
SP  - 221
EP  - 247
PB  - Springer
CY  - Heidelberg
ER  - 
TY  - JOUR
A1  - Lempiäinen, Harri
A1  - Couttet, Philippe
A1  - Bolognani, Federico
A1  - Müller, Arne
A1  - Dubost, Valérie
A1  - Luisier, Raphaëlle
A1  - Rio-Espinola, Alberto del
A1  - Vitry, Veronique
A1  - Unterberger, Elif B.
A1  - Thomson, John P.
A1  - Treindl, Fridolin
A1  - Metzger, Ute
A1  - Wrzodek, Clemens
A1  - Hahne, Florian
A1  - Zollinger, Tulipan
A1  - Brasa, Sarah
A1  - Kalteis, Magdalena
A1  - Marcellin, Magali
A1  - Giudicelli, Fanny
A1  - Braeuning, Albert
A1  - Morawiec, Laurent
A1  - Zamurovic, Natasa
A1  - Längle, Ulrich
A1  - Scheer, Nico
A1  - Schübeler, Dirk
A1  - Goodman, Jay
A1  - Chibout, Salah-Dine
A1  - Marlowe, Jennifer
A1  - Theil, Dietlinde
A1  - Heard, David J.
A1  - Grenet, Olivier
A1  - Zell, Andreas
A1  - Templin, Markus F.
A1  - Meehan, Richard R.
A1  - Wolf, Roland C.
A1  - Elcombe, Clifford R.
A1  - Schwarz, Michael
A1  - Moulin, Pierre
A1  - Terranova, Rémi
A1  - Moggs, Jonathan G.
T1  - Identification of Dlk1-Dio3 imprinted gene cluster non-coding RNAs as novel candidate biomarkers for liver tumor promotion
JF  - Toxicological Sciences
N2  - The molecular events during nongenotoxic carcinogenesis and their temporal order are poorly understood but thought to include long-lasting perturbations of gene expression. Here, we have investigated the temporal sequence of molecular and pathological perturbations at early stages of phenobarbital (PB) mediated liver tumor promotion in vivo. Molecular profiling (mRNA, microRNA [miRNA], DNA methylation, and proteins) of mouse liver during 13 weeks of PB treatment revealed progressive increases in hepatic expression of long noncoding RNAs and miRNAs originating from the Dlk1-Dio3 imprinted gene cluster, a locus that has recently been associated with stem cell pluripotency in mice and various neoplasms in humans. PB induction of the Dlk1-Dio3 cluster noncoding RNA (ncRNA) Meg3 was localized to glutamine synthetase-positive hypertrophic perivenous hepatocytes, sug- gesting a role for β-catenin signaling in the dysregulation of Dlk1-Dio3 ncRNAs. The carcinogenic relevance of Dlk1-Dio3 locus ncRNA induction was further supported by in vivo genetic dependence on constitutive androstane receptor and β-catenin pathways. Our data identify Dlk1-Dio3 ncRNAs as novel candidate early biomarkers for mouse liver tumor promotion and provide new opportunities for assessing the carcinogenic potential of novel compounds.
Y1  - 2012
U6  - https://doi.org/10.1093/toxsci/kfs303
SN  - 1094-2025
VL  - 131
IS  - 2
SP  - 375
EP  - 386
PB  - Oxford University Press
CY  - Oxford
ER  - 
TY  - JOUR
A1  - Ferrein, Alexander
A1  - Meyer, Thomas
T1  - A Brief Overview of Artificial Intelligence in South Africa
JF  - AI Magazine
N2  - South Africa in recent years is the establishment of a number of research hubs involved in AI activities ranging from mobile robotics and computational intelligence, to knowledge representation and reasoning, and human language technologies. In this survey we take the reader through a quick tour of the research being conducted at these hubs, and touch on an initiative to maintain and extend the current level of interest in AI research in the country.
Y1  - 2012
U6  - https://doi.org/10.1609/aimag.v33i1.2357
SN  - 0738-4602
VL  - 33
IS  - 1
SP  - 99
EP  - 101
PB  - AAAI
CY  - Menlo Park
ER  -