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31.
The aim of this study was to test a combination of automated headspace solid phase‐microextraction gas chromatography (GC) with chemometrical data treatment for the rapid differentiation of enzyme‐inactivated homogenates of new apple cultivars. The four cultivars Pinova, Piflora, Renora and Florina are characterized by different volatile patterns. Differences in the contents of volatiles were especially found for butyl acetate, ethyl butanoate, 2‐methyl butanol, ethyl acetate and 6‐methyl‐5‐hepten‐2‐ol. The used sample preparation method for GC coupled with pattern recognition of chromatograms is a useful tool for rapid and reliable determination of large numbers of samples. 相似文献
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Histamine is a pleiotropic mediator involved in a broad spectrum of (patho)-physiological processes, one of which is the regulation of inflammation. Compounds acting on three out of the four known histamine receptors are approved for clinical use. These approved compounds comprise histamine H1-receptor (H1R) antagonists, which are used to control allergic inflammation, antagonists at H2R, which therapeutically decrease gastric acid release, and an antagonist at H3R, which is indicated to treat narcolepsy. Ligands at H4R are still being tested pre-clinically and in clinical trials of inflammatory diseases, including rheumatoid arthritis, asthma, dermatitis, and psoriasis. These trials, however, documented only moderate beneficial effects of H4R ligands so far. Nevertheless, pre-clinically, H4R still is subject of ongoing research, analyzing various inflammatory, allergic, and autoimmune diseases. During inflammatory reactions in gut tissues, histamine concentrations rise in affected areas, indicating its possible biological effect. Indeed, in histamine-deficient mice experimentally induced inflammation of the gut is reduced in comparison to that in histamine-competent mice. However, antagonists at H1R, H2R, and H3R do not provide an effect on inflammation, supporting the idea that H4R is responsible for the histamine effects. In the present review, we discuss the involvement of histamine and H4R in inflammatory and inflammation-associated diseases of the gut. 相似文献
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Wulff Possart Detlef Fanter Monika Bauer Andreas Hartwig Otto-Diedrich Hennemann 《The Journal of Adhesion》2013,89(1-4):261-263
FTIR reflection spectroscopy was used to characterize thin films of a cyanurate prepolymer on evaporated aluminium and on silicon single crystal wafers. Both substrates are covered by their native oxides. The optical function of the prepolymer is derived from ATR measurements. The measured thin film reflectance spectra have to be interpreted in comparison with the corresponding bulk spectra obtained by simulation. All samples re-produce the bulk composition. The cyanate groups of the prepolymer are not involved in specific intermolecular interactions or in preferential orientation. This is also found for the triazine rings on Si. On Al, however, a considerable excess of triazine rings are oriented parallel to the interface. The vibration frequencies of the triazine groupings that are perpendicular to the Al substrate show a red shift to some 2–8 c?1. This special interaction effect does not occur on Si. Both the preferential orientation and the specific inter-molecular interaction act at least 100 nm into the prepolymer layer. 相似文献
36.
Tilmann Beck Karl-Heinz Lang Detlef Löhe 《Transactions of the Indian Institute of Metals》2010,63(2-3):195-202
The influence of superimposed total strain controlled HCF loadings on TMF life is presented and discussed for several cast Al-Si alloys, the Ni-base superalloy Inconel 617 and the cast iron GJS-700. Except for GJS-700, a threshold of the superimposed HCF loading is observed, below of which TMF life is not significantly affected. The strong decrease of TMF life as soon as the HCF amplitude exceeds this threshold is due to fundamental changes in the crack propagation mechanisms. The paper closes with a brief overview on lifetime prediction methods for TMF and their application in the case of TMF/HCF loadings. 相似文献
37.
Detlef Stiller Birgit Gaschler-Markefski Frank Baumgart Frank Schindler Claus Tempelmann Hans-Jochen Heinze henning Scheich 《Magma (New York, N.Y.)》1997,5(4):275-284
Prosodic modulation of speech provides information about emotional states of speakers (affective prosodies) or serves as syntactic
markers to change linguistic aspects of speech (linguistic prosodies). Previous electrophysiological investigations and studies
on patients with right or left hemisphere damage showed nonuniform results with respect to lateralization of prosodic processing.
In this study 20 healthy right-handed volunteers were investigated with functional magnetic resonance imaging of the acoustically
responsive areas on the supratemporal plane while detecting phonemes as control targets or prosodies in strings of nonsense
syllables and adjectives, the latter randomly intonated in a declarative, interrogative, commanding, happy, or sad fashion.
In control task A the phoneme /a/ was detected in the syllables. In control task B the phoneme /a/ was detected in the adjectives,
and in the experimental task C the sad intonations (affective) and in the experimental task D the interrogative intonations
(linguistic) had to be detected in the same material. In task A intensity-weighted volumes of activated voxels were not different
in the two hemispheres (laterality index 0). In task B with an irrelevant phoneme detection with respect to prosodic material,
the population split into two subgroups with similar right or left hemispheric lateralization of activity leading to an absolute
laterality index of 26.8 across all subjects. During detection of affective prosodies (task C), lateralization was maintained
yet the absolute laterality index reduced to 14.5, while there was no lateralization during detection of linguistic prosodies.
The sum of activations in the two hemispheres was the same across all tasks and subgroups, which suggests that the lateralizations
occurring with presentation and detection of prosodic material depend on a redistribution of activity between hemispheres. 相似文献
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39.
Sbastien Gentil Eulalia Crespo Isabel Rojo Aurlie Friang Clara Vias Francesc Teixidor Bohumír Grüner Detlef Gabel 《Polymer》2005,46(26):12218-12225
The influence of weakly coordinating anions with different shapes and substituents has been studied to get the overoxidation resistance limit of the material, ORL. The anions utilized are derivatives of [Co(C2B9H11)2]−, [B12H12]2− and [B12H11NH3]−. The following tendencies have been established (1) boron cluster monoanions are to date the anions that offer the highest stability to overoxidation of PPy doped materials (2) the ORL stability of the material can not be attributed only to the shape of the cluster (3) monoanionic clusters are far superior than dianionic to get an ORL rise (4) cluster charge density reduction results in ORL rise as has been observed in [Co(C2B9H11)2]− after incorporation of electron-withdrawing substituents with no electron back-donation (5) globular, rigid and large monoanions are less suitable for enhanced ORL values than elongated and non-rigid species (6) adequate anion's substitution produce a rise in the ORL of the material, thus polyether side-arms are beneficial with [Co(C2B9H11)2]−, whereas, T-shaped methylaryl groups are appealing in [B12H11NH3]− based materials, respectively, (7) substituents on the anions usually imply higher difficulty in the materials' growth. The high boron contents in these materials has permitted to learn on the fate of the doping anions during the overoxidation process. There is a built-up of the concentration of the doping anion in the electrolyte near surface area, whereas, a depletion is observed in the nearest inner layers. 相似文献
40.