@misc{JiangMansfeldKratzetal.2019,
  author    = {Jiang, Yi and Mansfeld, Ulrich and Kratz, Karl and Lendlein, Andreas},
  title     = {Programmable microscale stiffness pattern of flat polymeric substrates by temperature-memory technology},
  series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe},
  volume    = {9},
  journal   = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe},
  number    = {1},
  issn      = {1866-8372},
  doi       = {10.25932/publishup-46974},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-469745},
  pages     = {181 -- 188},
  year      = {2019},
  abstract  = {Temperature-memory technology was utilized to generate flat substrates with a programmable stiffness pattern from cross-linked poly(ethylene-co-vinyl acetate) substrates with cylindrical microstructures. Programmed substrates were obtained by vertical compression at temperatures in the range from 60 to 100 degrees C and subsequent cooling, whereby a flat substrate was achieved by compression at 72 degrees C, as documented by scanning electron microscopy and atomic force microscopy (AFM). AFM nanoindentation experiments revealed that all programmed substrates exhibited the targeted stiffness pattern. The presented technology for generating polymeric substrates with programmable stiffness pattern should be attractive for applications such as touchpads. optical storage, or cell instructive substrates.},
  language  = {en}
}
@article{EhrlichBecksGaedke2017,
  author    = {Ehrlich, Elias and Becks, Lutz and Gaedke, Ursula},
  title     = {Trait-fitness relationships determine how trade-off shapes affect species coexistence},
  series = {Ecology : a publication of the Ecological Society of America},
  volume    = {98},
  journal   = {Ecology : a publication of the Ecological Society of America},
  publisher = {Wiley},
  address   = {Hoboken},
  issn      = {0012-9658},
  doi       = {10.1002/ecy.2047},
  pages     = {3188 -- 3198},
  year      = {2017},
  abstract  = {Trade-offs between functional traits are ubiquitous in nature and can promote species coexistence depending on their shape. Classic theory predicts that convex trade-offs facilitate coexistence of specialized species with extreme trait values (extreme species) while concave trade-offs promote species with intermediate trait values (intermediate species). We show here that this prediction becomes insufficient when the traits translate non-linearly into fitness which frequently occurs in nature, e.g., an increasing length of spines reduces grazing losses only up to a certain threshold resulting in a saturating or sigmoid trait-fitness function. We present a novel, general approach to evaluate the effect of different trade-off shapes on species coexistence. We compare the trade-off curve to the invasion boundary of an intermediate species invading the two extreme species. At this boundary, the invasion fitness is zero. Thus, it separates trait combinations where invasion is or is not possible. The invasion boundary is calculated based on measurable trait-fitness relationships. If at least one of these relationships is not linear, the invasion boundary becomes non-linear, implying that convex and concave trade-offs not necessarily lead to different coexistence patterns. Therefore, we suggest a new ecological classification of trade-offs into extreme-favoring and intermediate-favoring which differs from a purely mathematical description of their shape. We apply our approach to a well-established model of an empirical predator-prey system with competing prey types facing a trade-off between edibility and half-saturation constant for nutrient uptake. We show that the survival of the intermediate prey depends on the convexity of the trade-off. Overall, our approach provides a general tool to make a priori predictions on the outcome of competition among species facing a common trade-off in dependence of the shape of the trade-off and the shape of the trait-fitness relationships.},
  language  = {en}
}
@misc{LiebigSarhanPrietzeletal.2016,
  author    = {Liebig, Ferenc and Sarhan, Radwan Mohamed and Prietzel, Claudia Christina and Reinecke, Antje and Koetz, Joachim},
  title     = {"Green" gold nanotriangles: synthesis, purification by polyelectrolyte/micelle depletion flocculation and performance in surface-enhanced Raman scattering},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-394430},
  pages     = {33561 -- 33568},
  year      = {2016},
  abstract  = {The aim of this study was to develop a one-step synthesis of gold nanotriangles (NTs) in the presence of mixed phospholipid vesicles followed by a separation process to isolate purified NTs. Negatively charged vesicles containing AOT and phospholipids, in the absence and presence of additional reducing agents (polyampholytes, polyanions or low molecular weight compounds), were used as a template phase to form anisotropic gold nanoparticles. Upon addition of the gold chloride solution, the nucleation process is initiated and both types of particles, i.e., isotropic spherical and anisotropic gold nanotriangles, are formed simultaneously. As it was not possible to produce monodisperse nanotriangles with such a one-step procedure, the anisotropic nanoparticles needed to be separated from the spherical ones. Therefore, a new type of separation procedure using combined polyelectrolyte/micelle depletion flocculation was successfully applied. As a result of the different purification steps, a green colored aqueous dispersion was obtained containing highly purified, well-defined negatively charged flat nanocrystals with a platelet thickness of 10 nm and an edge length of about 175 nm. The NTs produce promising results in surface-enhanced Raman scattering.},
  language  = {en}
}
@misc{TheteRojasNeumeyeretal.2013,
  author    = {Thete, Aniket and Rojas, Oscar and Neumeyer, David and Koetz, Joachim and Dujardin, Erik},
  title     = {Ionic liquid-assisted morphosynthesis of gold nanorods using polyethyleneimine-capped seeds},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-95196},
  pages     = {14294 -- 14298},
  year      = {2013},
  abstract  = {Seed-mediated gold nanorods with tunable lengths are prepared using new polyethyleneimine-capped gold nanoparticles synthesized in ionic liquid. The effect of polyethyleneimine and ionic liquid during nanorod growth is investigated and shows a marked effect on their final aspect ratio.},
  language  = {en}
}