@phdthesis{Wichura2011,
  author    = {Wichura, Henry},
  title     = {Topographic evolution of the East African Plateau : a combined study on lava-flow modeling and paleo-topography},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-52363},
  school      = {Universit{\"a}t Potsdam},
  year      = {2011},
  abstract  = {The East African Plateau provides a spectacular example of geodynamic plateau uplift, active continental rifting, and associated climatic forcing. It is an integral part of the East African Rift System and has an average elevation of approximately 1,000 m. Its location coincides with a negative Bouguer gravity anomaly with a semi-circular shape, closely related to a mantle plume, which influences the Cenozoic crustal development since its impingement in Eocene-Oligocene time. The uplift of the East African Plateau, preceding volcanism, and rifting formed an important orographic barrier and tectonically controlled environment, which is profoundly influenced by climate driven processes. Its location within the equatorial realm supports recently proposed hypotheses, that topographic changes in this region must be considered as the dominant forcing factor influencing atmospheric circulation patterns and rainfall distribution. The uplift of this region has therefore often been associated with fundamental climatic and environmental changes in East Africa and adjacent regions. While the far-reaching influence of the plateau uplift is widely accepted, the timing and the magnitude of the uplift are ambiguous and are still subject to ongoing discussion. This dilemma stems from the lack of datable, geomorphically meaningful reference horizons that could record surface uplift. In order to quantify the amount of plateau uplift and to find evidence for the existence of significant relief along the East African Plateau prior to rifting, I analyzed and modeled one of the longest terrestrial lava flows; the 300-km-long Yatta phonolite flow in Kenya. This lava flow is 13.5 Ma old and originated in the region that now corresponds to the eastern rift shoulders. The phonolitic flow utilized an old riverbed that once drained the eastern flank of the plateau. Due to differential erosion this lava flow now forms a positive relief above the parallel-flowing Athi River, which is mimicking the course of the paleo-river. My approach is a lava-flow modeling, based on an improved composition and temperature dependent method to parameterize the flow of an arbitrary lava in a rectangular-shaped channel. The essential growth pattern is described by a one-dimensional model, in which Newtonian rheological flow advance is governed by the development of viscosity and/or velocity in the internal parts of the lava-flow front. Comparing assessments of different magma compositions reveal that length-dominated, channelized lava flows are characterized by high effusion rates, rapid emplacement under approximately isothermal conditions, and laminar flow. By integrating the Yatta lava flow dimensions and the covered paleo-topography (slope angle) into the model, I was able to determine the pre-rift topography of the East African Plateau. The modeling results yield a pre-rift slope of at least 0.2°, suggesting that the lava flow must have originated at a minimum elevation of 1,400 m. Hence, high topography in the region of the present-day Kenya Rift must have existed by at least 13.5 Ma. This inferred mid-Miocene uplift coincides with the two-step expansion of grasslands, as well as important radiation and speciation events in tropical Africa. Accordingly, the combination of my results regarding the Yatta lava flow emplacement history, its location, and its morphologic character, validates it as a suitable "paleo-tiltmeter" and has thus to be considered as an important topographic and volcanic feature for the topographic evolution in East Africa.},
  language  = {en}
}
@article{WestermannStadieFrank2011,
  author    = {Westermann, Antje and Stadie, Nicole and Frank, Ulrike},
  title     = {Messung der Atem-Schluck-Koordination w{\"a}hrend normalem Schluck und unter Anwendung des Mendelsohn-Man{\"o}vers},
  series = {Spektrum Patholinguistik},
  journal   = {Spektrum Patholinguistik},
  number    = {4},
  issn      = {1869-3822},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-54286},
  pages     = {143 -- 147},
  year      = {2011},
  language  = {de}
}
@article{WestermannStadieFrank2011,
  author    = {Westermann, Antje and Stadie, Nicole and Frank, Ulrike},
  title     = {Messung der Atem-Schluck-Koordination w{\"a}hrend normalem Schluck und unter Anwendung des Mendelsohn- Man{\"o}vers},
  year      = {2011},
  language  = {de}
}
@article{WessigWawrzinekMoellnitzetal.2011,
  author    = {Wessig, Pablo and Wawrzinek, Robert and Moellnitz, Kristian and Feldbusch, Elvira and Schilde, Uwe},
  title     = {A new class of fluorescent dyes based on 1,3-benzodioxole and [1,3]-dioxolo[4.5-f]benzodioxole},
  series = {Tetrahedron letters},
  volume    = {52},
  journal   = {Tetrahedron letters},
  number    = {46},
  publisher = {Elsevier},
  address   = {Oxford},
  issn      = {0040-4039},
  doi       = {10.1016/j.tetlet.2011.09.058},
  pages     = {6192 -- 6195},
  year      = {2011},
  abstract  = {We report on synthesis and photophysical properties of a new class of fluorescent dyes. They are characterized by large Stokes-shifts, long fluorescence lifetimes in organic solvents and a pronounced dependency of the fluorescence lifetime on the solvent polarity. Also worthy of note is the high bleaching stability. To provide access to biochemical and medical applications a series of derivatives were prepared, which exhibit specific reactivity towards different biologically relevant functional groups (carboxylic acids, amines, maleimides, N-hydroxysuccinimide esters). Furthermore, two alkynes were prepared, which could be used in 'Click' chemistry.},
  language  = {en}
}
@article{WessigPickSchilde2011,
  author    = {Wessig, Pablo and Pick, Charlotte and Schilde, Uwe},
  title     = {First example of an atropselective dehydro-Diels-Alder (ADDA) reaction},
  series = {Tetrahedron letters},
  volume    = {52},
  journal   = {Tetrahedron letters},
  number    = {32},
  publisher = {Elsevier},
  address   = {Oxford},
  issn      = {0040-4039},
  doi       = {10.1016/j.tetlet.2011.06.024},
  pages     = {4221 -- 4223},
  year      = {2011},
  abstract  = {A new concept of a stereoselective synthesis of axially chiral biaryls, formed in the course of the dehydro-Diels-Alder (DDA) reaction, has been disclosed. It is based on asymmetric induction of the newly formed chirality axis by a chirality center, which is present in the two synthesized DDA reactants. Depending on the different length of the linkers joining the alkyne moieties the DDA reaction may be triggered photochemically or thermally, where only the thermal variant was stereoselective.},
  language  = {en}
}
@article{WessigPick2011,
  author    = {Wessig, Pablo and Pick, Charlotte},
  title     = {Photochemical synthesis and properties of axially chiral naphthylpyridines},
  series = {Journal of photochemistry and photobiology : A, Chemistry},
  volume    = {222},
  journal   = {Journal of photochemistry and photobiology : A, Chemistry},
  number    = {1},
  publisher = {Elsevier},
  address   = {Lausanne},
  issn      = {1010-6030},
  doi       = {10.1016/j.jphotochem.2011.06.006},
  pages     = {263 -- 265},
  year      = {2011},
  abstract  = {Five alkynyl pyridines were prepared and cyclized to naphthylpyridines as the main products in the course of a Photo-Dehydro-Diels-Alder reaction. Four of the final products are axially chiral and the determination of the rotational barrier by DFT calculations, dynamic NMR and H PLC experiments is demonstrated. (C) 2011 Elsevier B.V. All rights reserved.},
  language  = {en}
}
@article{WessigMoellnitzKellingetal.2011,
  author    = {Wessig, Pablo and M{\"o}llnitz, Kristian and Kelling, Alexandra and Schilde, Uwe},
  title     = {Crystal structure of 1r,2c,3c,4t,5t,6t-1,2,3,4,5,6-hexakis-trimethylsilanyloxy-cyclohexane, C24H60O6Si6},
  series = {Zeitschrift f{\"u}r Kristallographie : international journal for structural, physical and chemical aspects of crystalline materials ; New crystal structures},
  volume    = {226},
  journal   = {Zeitschrift f{\"u}r Kristallographie : international journal for structural, physical and chemical aspects of crystalline materials ; New crystal structures},
  number    = {2},
  publisher = {De Gruyter Oldenbourg},
  address   = {M{\"u}nchen},
  issn      = {1433-7266},
  doi       = {10.1524/ncrs.2011.0105},
  pages     = {228 -- 230},
  year      = {2011},
  abstract  = {C24H60O6Si6, triclinic, P (1) over bar (no. 2), a = 11.307(2) angstrom, b = 12.159(2) angstrom, = 16.576(2) angstrom, alpha = 109.47(1)degrees, beta = 94.64(1)degrees, gamma = 111.65(1)degrees, V = 1942.3 angstrom(3), Z = 2, R-gt(F) = 0.043, wR(ref)(F-2) = 0.118, T = 210 K.},
  language  = {en}
}
@article{WessigMatthesPick2011,
  author    = {Wessig, Pablo and Matthes, Annika and Pick, Charlotte},
  title     = {The photo-dehydro-Diels-Alder (PDDA) reaction},
  series = {Organic \& biomolecular chemistry : an international journal of synthetic, physical and biomolecular organic chemistry},
  volume    = {9},
  journal   = {Organic \& biomolecular chemistry : an international journal of synthetic, physical and biomolecular organic chemistry},
  number    = {22},
  publisher = {Royal Society of Chemistry},
  address   = {Cambridge},
  issn      = {1477-0520},
  doi       = {10.1039/c1ob06066j},
  pages     = {7599 -- 7605},
  year      = {2011},
  abstract  = {The photo-dehydro-Diels-Alder (PDDA) reaction is a valuable extension of the classical Diels-Alder (DA) reaction. The PDDA reaction differs from the DA reaction by the replacement of one of the C-C-double bonds of the diene moiety by a C-C triple bond and by the photochemical triggering of the reaction. This entails that, in contrast to the DA reaction, the PDDA reaction proceeds according to a multistage mechanism with biradicals and cycloallenes as intermediates. The PDDA reaction provides access to a considerable variety of compound classes. For example, 1-phenylnaphthlenes, 1,1'-binaphthyls, N-heterocyclic biaryls, and naphthalenophanes could be obtained by this reaction.},
  language  = {en}
}
@article{WessigMatthes2011,
  author    = {Wessig, Pablo and Matthes, Annika},
  title     = {Preparation of Strained Axially Chiral (1,5)Naphthalenophanes by Photo-dehydro-Diels-Alder Reaction},
  series = {Journal of the American Chemical Society},
  volume    = {133},
  journal   = {Journal of the American Chemical Society},
  number    = {8},
  publisher = {American Chemical Society},
  address   = {Washington},
  issn      = {0002-7863},
  doi       = {10.1021/ja109118m},
  pages     = {2642 -- 2650},
  year      = {2011},
  abstract  = {The preparation of 10 (1,5)naphthalenophanes (10a-j) by photo-dehydro-Diels-Alder (PDDA) reaction is described. Owing to hindered rotation around the biaryl axis, compounds 10 are axially chiral and the separation of enantiomers by chiral HPLC was demonstrated in three cases (10a,b,e). The absolute configuration of the isolated enantiomers could be unambiguously determined by comparison of calculated and measured circular dichroism (CD) spectra. Furthermore, we analyzed ring strain phenomena of (1,5)naphthalenophanes 10. Depending on the length of the linker units, one can distinguish three classes of naphthalenophanes. Compounds 10a-c are highly strained (E-STR = 7-31 kcal/mol), and the strain is caused by small bond angles in the linker unit and deformation of the naphthalene moiety. Another type of strain is observed if the linker unit becomes relatively long (10g,h) originating from transannular interactions and is comparable with the well-known strain of medium sized rings. The naphthalenophanes 10d-f with a linker length of 10-14 atoms are only marginally strained. To clearly discriminate the different sources of strain, we defined two geometrical parameters (average central dihedral angle delta(C) and naphthalene thickness D-N) and demonstrated that they are well-suited to indicate naphthalene deformation of our naphthalenophanes 10 as well as of ten model naphthalenophanes (I-X) with different linker lengths and linking positions.},
  language  = {en}
}
@article{WeskottFanselow2011,
  author    = {Weskott, Thomas and Fanselow, Gisbert},
  title     = {On the informativity of different measures of linguistic acceptability},
  series = {Language : journal of the Linguistic Society of America},
  volume    = {87},
  journal   = {Language : journal of the Linguistic Society of America},
  number    = {2},
  publisher = {Linguistic Society of America},
  address   = {Washington},
  issn      = {0097-8507},
  pages     = {249 -- 273},
  year      = {2011},
  abstract  = {This article deals with the claim that the MAGNITUDE ESTIMATION (ME) method of gathering acceptability judgments produces data that are more informative for linguists than binary or n-point scale judgments. We performed three acceptability-rating experiments that directly compared ME data to binary and seven-point scale data. The results clearly falsify the hypothesis that data gathered by the ME method carry a larger amount of information about the acceptability of a given linguistic phenomenon. The three measures are largely equivalent with respect to informativity. Moreover, ME judgments are shown to be more liable to producing spurious variance under certain circumstances.*},
  language  = {en}
}