Looking for a pattern: An MEG study on the abstract mismatch negativity in musicians and nonmusicians

Background  

The mismatch negativity (MMN) is an early component of event-related potentials/fields, which can be observed in response to violations of regularities in sound sequences. The MMN can be elicited by simple feature (e.g. pitch) deviations in standard oddball paradigms as well as by violations of more complex sequential patterns. By means of magnetoencephalography (MEG) we investigated if a pattern MMN could be elicited based on global rather than local probabilities and if the underlying ability to integrate long sequences of tones is enhanced in musicians compared to nonmusicians.     

Treatment in Swelling Solutions Modifying Cellulose Fiber Reactivity – Part 1: Accessibility and Sorption

Of prime importance in reactions involving insoluble cellulosic fibers is the sorption of reagents, which is governed by their degrees of accessibility in substrates. Swelling treatments of cellulosics in alkali solutions alter substrate accessibility leading to changes in their reactivity. In this paper, the first of a two-part series, we collate and examine the results from various studies involving different techniques to characterize modifications in cellulosic fibers after swelling treatments in alkali solutions. Results from measurements of structure and accessibility in fibers with techniques such as water retention, inverse size exclusion chromatography (ISEC), iodine sorption, fiber diameters, and fiber-splitting propensities indicate that the influence of swelling treatments on fiber structure/accessibility is differs with alkali type. The results show that a non-uniform rather than uniform distribution of reagents within structures is a more accurate representation of reactions involving swollen cellulosic fibers. Hence, the observed changes in cellulose-fiber reactivity are governed by the degrees of fiber swelling, and reagent sorption and accessibility during swelling treatments.     

Ubertragungsvorschriften zur aufstellung der G- und F-matrixelemente des oktaedrischen systems XY6 (Oh)

The elements of the G and F matrices and the vibrational equations are set up in terms of symmetry coordinates, using transformation rules for the case of the octahedral system XY₆ (O_h).     

The Vinylidene/Acyl Coupling at Rhenium Centers

The reaction of [Re(CO₃)L₂Cl] (L = (MeI)₃P, 1a ; L = (i-PrO)₃P, 1b ; L = (PhO)₃P, 1c ; L = Me₃P, 1d ; L = Et₃P, 1e ) with t-BuLi and phenylacetylene in THF affords bis (phosphorus donor) (dicarbonyl) {η²(C,O)-[(E)-4,4-dimethyl-3-oxo-1-phenylpent-1-3n-2-yl]}rhenium (L = (MeO)₃P, 2b ; L = (PhO)₃P, 2c ; L = Me₃P, 2d ; L = Et₃P, 2c ). Compounds 2b and 2d were characterized by X-ray structure analysis.     

Facile synthetic approach to novel core-extended perylene carboximide dyes

The straightforward synthesis of two new classes of core-extended perylene chromophores, dibenzocoronene tetracarboxdiimide and indenoperylene dicarboxmonoimide, proves that directional enlargement of the aromatic pi-system leads to tailored bathochromic and hypsochromic shifts.     

Gas-Phase Enrichment of Multiply Charged Peptide Ions by Differential Ion Mobility Extend the Comprehensiveness of SUMO Proteome Analyses

The small ubiquitin-like modifier (SUMO) is a member of the family of ubiquitin-like modifiers (UBLs) and is involved in important cellular processes, including DNA damage response, meiosis and cellular trafficking. The large-scale identification of SUMO peptides in a site-specific manner is challenging not only because of the low abundance and dynamic nature of this modification, but also due to the branched structure of the corresponding peptides that further complicate their identification using conventional search engines. Here, we exploited the unusual structure of SUMO peptides to facilitate their separation by high-field asymmetric waveform ion mobility spectrometry (FAIMS) and increase the coverage of SUMO proteome analysis. Upon trypsin digestion, branched peptides contain a SUMO remnant side chain and predominantly form triply protonated ions that facilitate their gas-phase separation using FAIMS. We evaluated the mobility characteristics of synthetic SUMO peptides and further demonstrated the application of FAIMS to profile the changes in protein SUMOylation of HEK293 cells following heat shock, a condition known to affect this modification. FAIMS typically provided a 10-fold improvement of detection limit of SUMO peptides, and enabled a 36% increase in SUMO proteome coverage compared to the same LC-MS/MS analyses performed without FAIMS.

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Graphical Abstract ?

     

Star-shaped oligobenzoates: non-conventional mesogens forming columnar helical mesophases

Star-shaped mesogens with a phloroglucinol or a trimesic acid core and oligobenzoate arms with up to five repeating units have been synthesised. These non-conventional mesogens form various columnar mesophases over a broad temperature range. The liquid-crystal phases were characterised by optical microscopy, differential scanning calorimetry, X-ray diffraction, dilatometry and solid-state NMR spectroscopy. In addition to the high-temperature hexagonal columnar phases, the columnar self-assemblies undulate upon cooling and consequently form higher-ordered body-centred orthorhombic columnar 3D structures. A model of E-shaped folded conformers helically displaced along the columns is proposed. Helical preorganisation in the hexagonal phase precedes the transition to the low-temperature phases. Space filling and nano-segregation compete in the self-organisation process, thus aliphatic chains and the polar oligobenzoate scaffold are not perfectly separated in these star-shaped mesogens.     

Integer Programming Duality in Multiple Objective Programming

The weighted sums approach for linear and convex multiple criteria optimization is well studied. The weights determine a linear function of the criteria approximating a decision makers overall utility. Any efficient solution may be found in this way. This is not the case for multiple criteria integer programming. However, in this case one may apply the more general e-constraint approach, resulting in particular single-criteria integer programming problems to generate efficient solutions. We show how this approach implies a more general, composite utility function of the criteria yielding a unified treatment of multiple criteria optimization with and without integrality constraints. Moreover, any efficient solution can be found using appropriate composite functions. The functions may be generated by the classical solution methods such as cutting plane and branch and bound algorithms.     

International research supported by the German Research Foundation (DFG)--examples of activities in the field of chemistry

Chemical sciences play an important role in addressing global challenges such as energy supply and storage, health, or environment. Research in these complex areas requires more and more international collaborative work. In fact collaborative research has been common practice for many years in the field of chemistry. This situation is also reflected by the increasing number of German funding programs, which promote international and joint research collaborations, in order to achieve a more effective use of both national and international resources in the field of chemistry.