@phdthesis{Schieffer2012,
  author    = {Schieffer, Andre},
  title     = {Studies on diversity and coexistence in an experimental microbial community},
  pages     = {76 Bl. : Ill.},
  year      = {2012},
  abstract  = {Biodiversity and the coexistence of species have puzzled and fascinated biologists since decades and is a hotspot in todays' natural sciences. Preserving this biodiversity is a great challenge as habitats and environments underlying tremendous changes like climate change and the loss of natural habitats, which are mainly due to anthropogenic influences. The coexistence of numerous species even in homogeneous environments is a stunning feature of natural communities and has been summarized under the term 'paradox of plankton'. Up to now, there are several mechanisms discussed, which may contribute to local and global diversity of organisms. Several interspecific trade offs have been identified maintaining the coexistence of species like their abilities regarding competition and predator avoidance, their capability to disperse in space and time, and their ability to exploit variable resources. Further, micro-evolutionary dynamics supporting the coexistence of species have been added to our knowledge, and deriving from theoretical deterministic models, non-linear dynamics which describe the temporal fluctuation of abundances of organisms. Whereas competition and predation seem to be clue structural elements within interacting organisms, the intrinsic dynamic behavior - by means of temporal changes in abundance - plays an important role regarding coexistence within a community. The present work sheds light on different factors affecting the coexistence of species using experimental microbial model systems consisting of a bacterivorous ciliate as the predator and two bacteria strains as prey organism. Additionally, another experimental setup consisting of two up to five bacteria species competing for one limiting resource was investigated. Highly controllable chemostat systems were established to exclude extrinsic disturbances. According to theoretical analyses I was able to show - experimentally and theoretically - that phenotypic plasticity of one species within a microbial one-predator-two-prey food web enlarges the range of possible coexistence of all species under different dynamic conditions, compared to a food web without phenotypic plasticity. This was accompanied by non-linear (chaotic) population dynamics within all experimental systems showing phenotypic plasticity. The experiments on the interplay of competition, predation and invasion showed that all aspects have an influence on species coexistence. Under undisturbed controlled conditions all aspects were analyzed in detail and in combination. Populations showed oscillations which were shown by quasi-chaotic attractors in phase space diagrams. Competition experiments with two up to five bacteria species competing for one limiting resource showed that all organisms were able to coexist which was mediated by species oscillations entering a regime of chaos. Besides that fact it was found, that the productivity (biomass) as well as the total cell numbers - under the same nutrition supply - increased by an increasing number of species in the experimental systems. Up to now, the occurrence of non-linear dynamics in well controlled experimental studies has been recognized several times and this phenomenon seemed to be more common in natural systems than generally assumed.},
  language  = {en}
}
@inproceedings{StreunAlKaddoumParletal.2012,
  author    = {Streun, M. and Al-Kaddoum, R. and Parl, C. and Pietrzyk, U. and Ziemons, Karl and Waasen, S. van},
  title     = {Simulation studies of optical photons in monolithic block scintillators},
  series = {2011 IEEE Nuclear Science Symposium Conference Record (NSS/MIC)},
  booktitle = {2011 IEEE Nuclear Science Symposium Conference Record (NSS/MIC)},
  publisher = {IEEE},
  address   = {New York},
  isbn      = {978-1-4673-0120-6 (electronic ISBN)},
  doi       = {10.1109/NSSMIC.2011.6154621},
  pages     = {1380 -- 1382},
  year      = {2012},
  abstract  = {The interest in PET detectors with monolithic block scintillators is growing. In order to obtain high spatial resolutions dedicated positioning algorithms are required. But even an ideal algorithm can only deliver information which is provided by the detector. In this simulation study we investigated the light distribution on one surface of cuboid LSO scintillators of different size. Scintillators with a large aspect ratio (small footprint and large height) showed significant position information only for a minimum interaction depth of the gamma particle. The results allow a quantitative estimate for a useful aspect ratio.},
  language  = {en}
}
@article{LustfeldPithanReissel2012,
  author    = {Lustfeld, H. and Pithan, C. and Reißel, Martin},
  title     = {Metallic electrolyte composites in the framework of the brick-layer model},
  series = {Journal of the European Ceramic Society},
  volume    = {32},
  journal   = {Journal of the European Ceramic Society},
  number    = {4},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0955-2219},
  doi       = {10.1016/j.jeurceramsoc.2011.10.017},
  pages     = {859 -- 864},
  year      = {2012},
  abstract  = {It is well known that the already large dielectric constants of some electrolytes like BaTiO₃ can be enhanced further by adding metallic (e.g. Ni, Cu or Ag) nanoparticles. The enhancement can be quite large, a factor of more than 1000 is possible. The consequences for the properties will be discussed in the present paper applying a brick-layer model (BLM) for calculating dc-resistivities of thin layers and a modified one (PBLM) that includes percolation for calculating dielectric properties of these materials. The PBLM results in an at least qualitative description and understanding of the physical phenomena: This model gives an explanation for the steep increase of the dielectric constant below the percolation threshold and why this increase is connected to a dramatic decrease of the breakdown voltage as well as the ability of storing electrical energy. We conclude that metallic electrolyte composites like BaTiO₃ are not appropriate for energy storage.},
  language  = {en}
}
@article{KernSchelthoffMathieu2012,
  author    = {Kern, Alexander and Schelthoff, Christof and Mathieu, Moritz},
  title     = {Detaillierte Berechnung der Einfangwirksamkeiten von Fangeinrichtungen},
  series = {Elektro-Praktiker},
  volume    = {66},
  journal   = {Elektro-Praktiker},
  number    = {4},
  publisher = {Huss Medien},
  address   = {Berlin},
  issn      = {0013-5569},
  pages     = {6 Seiten},
  year      = {2012},
  abstract  = {Im Beitrag wird zun{\"a}chst das Verfahren eines dynamischen elektro-geometrischen Modells vorgestellt. Dieses arbeitet im Gegensatz zum klassischen Blitzkugel-Verfahren nicht mit konstanten Radien; vielmehr wird der Radius der Blitzkugel variiert. Dabei werden ausschließlich vorhandene und in internationalen Normen anerkannte Ergebnisse, blitzphysikalische Grundlagen und Untersuchungen verwendet, und auf deren Grundlage ein numerisches Verfahren erarbeitet. Mit dem dynamischen elektro-geometrischen Modell werden dann einige Beispiele des Schutzes mit Fangstangen, die gem{\"a}ß dem klassischen Blitzkugel-Verfahren nach DIN EN 62305-3 f{\"u}r die Schutzklassen I - II - III - IV geplant sind, untersucht. Es wird gezeigt, dass die Einfangwirksamkeiten wesentlich h{\"o}her sind als in der Normenreihe DIN EN 62305 selbst angegeben. Grund daf{\"u}r ist die Tatsache, dass das Blitzkugel-Verfahren sehr konservativ aufgebaut ist und dem Planer von Blitzschutzsystemen nur die m{\"o}glichen Stellen f{\"u}r einen Einschlag aufzeigt, ohne eine Bewertung der Einschlagsh{\"a}ufigkeit zu liefern. Andererseits bedeutet dies jedoch, dass man mit dem klassischen Blitzkugel-Verfahren stets auf der „sicheren Seite" liegt.},
  language  = {de}
}
@inproceedings{ReisertGeisslerFloerkeetal.2012,
  author    = {Reisert, Steffen and Geissler, H. and Fl{\"o}rke, R. and Weiler, C. and Wagner, P. and Sch{\"o}ning, Michael Josef},
  title     = {Characterisation of aseptic sterilisation processes using an electronic nose},
  series = {Nanoscale Science and Technology (NS\&T´12) : Proceedings Book Humboldt Kolleg ; Tunisia, 17-19 March, 2012},
  booktitle = {Nanoscale Science and Technology (NS\&T´12) : Proceedings Book Humboldt Kolleg ; Tunisia, 17-19 March, 2012},
  editor    = {Abdelghani, Adnane and Sch{\"o}ning, Michael Josef},
  pages     = {45 -- 45},
  year      = {2012},
  language  = {en}
}
@inproceedings{YoshinobuMiyamotoWagneretal.2012,
  author    = {Yoshinobu, Tatsuo and Miyamoto, Ko-Ichiro and Wagner, Torsten and Sch{\"o}ning, Michael Josef},
  title     = {Miniaturized and high-speed chemical imaging systems},
  series = {Nano-Biomedical Engineering 2012. Proceedings of the Tohoku University Global Centre of Excellence Programme, Sakura Hall, Tohoku University, Sendai Japan, 5 - 6 March 2012},
  booktitle = {Nano-Biomedical Engineering 2012. Proceedings of the Tohoku University Global Centre of Excellence Programme, Sakura Hall, Tohoku University, Sendai Japan, 5 - 6 March 2012},
  editor    = {Yamaguchi, Takami},
  publisher = {World Scientific},
  address   = {Singapur},
  doi       = {10.1142/9781848169067_0045},
  pages     = {386 -- 395},
  year      = {2012},
  language  = {en}
}
@article{GrinsvenBonStrauvenetal.2012,
  author    = {Grinsven, Bart van and Bon, Natalie vanden and Strauven, Hannelore and Grieten, Lars and Murib, Mohammed and Jim{\´e}nez Monroy, Kathia L. and Janssens, Stoffel D. and Haenen, Ken and Sch{\"o}ning, Michael Josef and Vermeeren, Veronique and Ameloot, Marcel and Michiels, Luc and Thoelen, Ronald and Ceuninck, Ward de and Wagner, Patrick},
  title     = {Heat-Transfer Resistance at Solid-Liquid Interfaces: A Tool for The Detection of Single Nucleotide Polymorphisms in DNA.},
  series = {ACS Nano},
  volume    = {6},
  journal   = {ACS Nano},
  number    = {3},
  publisher = {ACS Publications},
  address   = {Washington, DC},
  issn      = {1936-086X},
  doi       = {10.1021/nn300147e},
  pages     = {2712 -- 2721},
  year      = {2012},
  abstract  = {In this article, we report on the heat-transfer resistance at interfaces as a novel, denaturation-based method to detect single-nucleotide polymorphisms in DNA. We observed that a molecular brush of double-stranded DNA grafted onto synthetic diamond surfaces does not notably affect the heat-transfer resistance at the solid-to-liquid interface. In contrast to this, molecular brushes of single-stranded DNA cause, surprisingly, a substantially higher heat-transfer resistance and behave like a thermally insulating layer. This effect can be utilized to identify ds-DNA melting temperatures via the switching from low- to high heat-transfer resistance. The melting temperatures identified with this method for different DNA duplexes (29 base pairs without and with built-in mutations) correlate nicely with data calculated by modeling. The method is fast, label-free (without the need for fluorescent or radioactive markers), allows for repetitive measurements, and can also be extended toward array formats. Reference measurements by confocal fluorescence microscopy and impedance spectroscopy confirm that the switching of heat-transfer resistance upon denaturation is indeed related to the thermal on-chip denaturation of DNA.},
  language  = {en}
}
@inproceedings{BohrnStuetzFleischeretal.2012,
  author    = {Bohrn, U. and St{\"u}tz, E. and Fleischer, M. and Sch{\"o}ning, Michael Josef and Wagner, P.},
  title     = {Towards a paradigm change - mammalian cells as sensitive biosensor layers for the detection of unexpected toxic substances in air},
  series = {Nanoscale Science and Technology (NS\&T´12) : Proceedings Book Humboldt Kolleg ; Tunisia, 17-19 March, 2012},
  booktitle = {Nanoscale Science and Technology (NS\&T´12) : Proceedings Book Humboldt Kolleg ; Tunisia, 17-19 March, 2012},
  editor    = {Abdelghani, Adnane and Sch{\"o}ning, Michael Josef},
  pages     = {44 -- 44},
  year      = {2012},
  language  = {en}
}
@article{SpelthahnKirsanovLeginetal.2012,
  author    = {Spelthahn, Heiko and Kirsanov, Dmitry and Legin, Andrey and Osterrath, Thomas and Schubert, J{\"u}rgen and Zander, Willi and Sch{\"o}ning, Michael Josef},
  title     = {Development of a thin-film sensor array for analytical monitoring of heavy metals in aqueous solutions},
  series = {Physica Status Solidi (a)},
  volume    = {209},
  journal   = {Physica Status Solidi (a)},
  number    = {5},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  isbn      = {1862-6319},
  doi       = {10.1002/pssa.201100733},
  pages     = {885 -- 891},
  year      = {2012},
  abstract  = {In industrial processes there is a variety of heavy metals (e.g., copper, zinc, cadmium, and lead) in use for wires, coatings, paints, alloys, batteries, etc. Since the application of these transition metals for industry is inevitable, it is a vital task to develop proper analytical techniques for their monitoring at low activity levels, especially because most of these elements are acutely toxic for biological organisms. The determination of ions in solution by means of a simple and inexpensive sensor array is, therefore, a promising task. In this work, a sensor array with heavy metal-sensitive chalcogenide glass membranes for the simultaneous detection of the four ions Ag⁺, Cu2⁺, Cd2⁺, and Pb2⁺ in solution is realized. The results of the physical characterization by means of microscopy, profilometry, Rutherford backscattering spectroscopy (RBS), and scanning electron microscopy (SEM) as well as the electrochemical characterization by means of potentiometric measurements are presented. Additionally, the possibility to expand the sensor array by polymeric sensor membranes is discussed.},
  language  = {en}
}
@article{SpelthahnSchubertSchoening2012,
  author    = {Spelthahn, Heiko and Schubert, J{\"u}rgen and Sch{\"o}ning, Michael Josef},
  title     = {D{\"u}nnschichtsensoren f{\"u}r die Schwermetallanalytik},
  series = {GIT : Labor-Fachzeitschrift},
  volume    = {56},
  journal   = {GIT : Labor-Fachzeitschrift},
  number    = {4},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  issn      = {0016-3538},
  pages     = {285 -- 287},
  year      = {2012},
  abstract  = {Die Detektion von Schadstoffen repr{\"a}sentiert in der Umweltanalytik eine wichtige Aufgabenstellung. Gerade die Abwasser- bzw. Brauchwasseranalytik sowie die Prozesskontrolle haben einen hohen Stellenwert. Siliziumbasierte D{\"u}nnschichtsensoren bieten eine kosteng{\"u}nstige M{\"o}glichkeit, „online"-Messungen bzw. Vor-Ort-Messungen zeitnah durchzuf{\"u}hren. In dieser Arbeit wird ein potentiometrisches Sensorarray auf der Basis von Chalkogenidgl{\"a}sern zur Detektion von Schwermetallen in w{\"a}ssrigen Medien vorgestellt.},
  language  = {en}
}