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81.
Damage evolution of the alloy IN 738 LC at high temperature low cycle fatigue Herrn Professor K.-T. Rie zum 60. Geburtstag Interrupted Low-Cycle-Fatigue tests have been carried out with IN 738 LC at 850°C. The specimens were extensively examined by SEM to quantify the evolution of fatigue damage. Surface crack nucleation at oxidized grain boundaries occured during the whole experiments. The coalescence of cracks was the dominant mechanism which lead to macro crack evolution and the final fracture.  相似文献   
82.
Obesity develops early in childhood and is accompanied by early signs of adipose tissue (AT) dysfunction and metabolic disease in children. In order to analyse the molecular processes during obesity-related AT accumulation in children, we investigated genome-wide expression profiles in AT samples, isolated adipocytes, and stromal vascular fraction (SVF) cells and assessed their relation to obesity as well as biological and functional AT parameters. We detected alterations in gene expression associated with obesity and related parameters, i.e., BMI SDS, adipocyte size, macrophage infiltration, adiponectin, and/or leptin. While differential gene expression in AT and adipocytes shared an enrichment in metabolic pathways and pathways related to extracellular structural organisation, SVF cells showed an overrepresentation in inflammatory pathways. In adipocytes, we found the strongest positive association for epidermal growth factor-like protein 6 (EGFL6) with adipocyte hypertrophy. EGFL6 was also upregulated during in vitro adipocyte differentiation. In children, EGFL6 expression was positively correlated to parameters of AT dysfunction and metabolic disease such as macrophage infiltration into AT, hs-CRP, leptin levels, and HOMA-IR. In conclusion, we provide evidence for early alterations in AT gene expression related to AT dysfunction in children and identified EGFL6 as potentially being involved in processes underlying the pathogenesis of metabolic disease.  相似文献   
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Abstract

We have developed a fixed beam direct writing laser lithography system with a minimum feature size of 400nm at 457nm wavelength and a writing speed of 4·2mm/s with total system costs of less than 100 000 US$.  相似文献   
85.
We show that many NP-hard sets have heuristic polynomial-time algorithms with high probability weight of correctness with respect to generalizations of Procaccia and Rosenschein’s junta distributions.  相似文献   
86.
A series of commercially available nanosized barium titanates has been investigated with respect to their use as high-k-ceramic filler in polymer based composites with improved dielectric properties. The thermal treatment of the barium titanate powders at 1,000°C causes a significant increase of the composite’s permittivity. X-ray diffraction experiments prior and after heat treatment revealed that the barium titanate with smallest particle size and the largest specific surface area possesses the thermodynamically unstable cubic phase. In case of the other investigated barium titanates the crystal lattice is distorted. Thermal treatment induces the phase change into the tetragonal one and crystal lattice relaxation enabling higher permittivity values. Composites with a solid load around 78 wt% with a bimodal particle size distribution show high permittivities around 50 and a low loss factor around 5‰ suitable for the realization of embedded capacitors via screen printing or tape casting.  相似文献   
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Four visual-world experiments, in which listeners heard spoken words and saw printed words, compared an optimal-perception account with the theory of phonological underspecification. This theory argues that default phonological features are not specified in the mental lexicon, leading to asymmetric lexical matching: Mismatching input (pin) activates lexical entries with underspecified coronal stops (tin), but lexical entries with specified labial stops (pin) are not activated by mismatching input (tin). The eye-tracking data failed to show such a pattern. Although words that were phonologically similar to the spoken target attracted more looks than did unrelated distractors, this effect was symmetric in Experiment 1 with minimal pairs (tin–pin) and in Experiments 2 and 3 with words with an onset overlap (peacock–teacake). Experiment 4 revealed that /t/-initial words were looked at more frequently if the spoken input mismatched only in terms of place than if it mismatched in place and voice, contrary to the assumption that /t/ is unspecified for place and voice. These results show that speech perception uses signal-driven information to the fullest, as was predicted by an optimal perception account. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
89.
A switchable metasurface composed of plasmonic split ring resonators and a polymer-stabilized liquid crystal blue phase is developed. Owing to field-induced birefringence (electro-optic Kerr effect), the state of polarization of the incident near infrared radiation changes, when a voltage is applied to the liquid crystal. Thus, different resonant modes of the split ring resonators can be addressed and the transmission spectrum changes accordingly. In comparison with other liquid crystal phases, blue phases have several advantages. For example, they are optically isotropic in the field-off state, so that no alignment layer is required. The results of the present study indicate that the advantages of these mesophases can be utilized for switchable metasurfaces.  相似文献   
90.
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