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1.
Since intelligibility of synthetic speech is no longer the main criterion on which to base quality judgements, reliable methods for prosody evaluation become more important. We propose a method called PURR (Prosody Unveiling through Restricted Representation) to evaluate the prosodic component of a synthesis system without the interference of other system components. In PURR, the stimuli are reduced to their prosodic content. The method has proven to be suitable for test designs with naıve listeners. It can be used for comparative studies as well as for diagnostic analyses and is, therefore, a useful tool for basic research on the perception of prosodic phenomena. In this paper we first describe how the best signal manipulation method was determined using perception tests. The appropriateness of the resulting signal is further assessed in a recognition test of syntactic structure. We then report on further validations of the proposed method: different ways of synthetic prosody modelling are evaluated, both in comparison with human prosody and amongst different synthesis systems.  相似文献   
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A collection of new reversible glycosidase inhibitors of the iminoalditol type featuring N‐substituents containing perfluorinated regions has been prepared for evaluation of physicochemical, biochemical and diagnostic properties. The vast variety of feasible oligofluoro moieties allows for modular approaches to customised structures according to the intended applications, which are influenced by the fluorine content as well as the distance of the fluorous moiety from the ring nitrogen. The first examples, in particular in the D ‐galacto series, exhibited excellent inhibitory activities. A preliminary screen with two human cell lines showed that, at subinhibitory concentrations, they are powerful pharmacological chaperones enhancing the activities of the catalytically handicapped lysosomal D ‐galactosidase mutants associated with GM1 gangliosidosis and Morquio B disease.  相似文献   
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We investigate the dimensionality of inhomogeneous spin modulation patterns in the cuprate family of high-temperature superconductors with particular focus on 1/8-doped lanthanum cuprates. We compare one-dimensional stripe modulation pattern with two-dimensional checkerboard of spin vortices in the context of nuclear quadrupole resonance (NQR) and muon spin rotation (μSR) experiments. In addition, we also consider the third pattern, a two-dimensional superposition of spin spirals. Overall, we have found that none of the above patterns leads to a consistent interpretation of the two types of experiments considered. This, in particular, implies that the spin vortex checkerboard cannot be ruled out on the basis of available NQR/μSR experimental results.  相似文献   
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Saving potentials of up to 30% in capital and operating costs are the driving forces behind the increase in the application of dividing-wall columns in industry. However, a lack of knowledge still exists when dealing with the start-up of dividing-wall columns, which is inherently a strongly nonlinear process. Here, for the first time the start-up of dividing-wall columns is explored, where the starting point is an empty column at ambient conditions. A model is presented which is capable of predicting the dynamic discrete-continuous changes which are characteristic of dividing-wall columns. The proposed process model takes into account the heat transfer across the dividing wall as well as the vapor distribution below the dividing wall. The degree of accuracy of the model is clearly determined by comparing different simplifications, e.g. a constant vapor distribution ratio equal to the steady-state value. The detailed studies were carried out with strict product specifications so that the influence of process parameters could be quantified. The rigorous process model and the obtained simulation results presented in this study provide a promising basis for developing and applying optimal start-up policies for dividing-wall columns.  相似文献   
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A cycloisomerization of enynes with a benign calcium catalyst is presented exploring a complementary reactivity to that usually found in transition and noble metal‐catalyzed reactions. Thereby, a systematic investigation of the π‐activation of alkynes with reactive carbocations has been realized and ketones of various ring sizes were easily accessed. We are certain that these basic investigations will pave the way for the elaboration of further reactions based on the reaction principles discovered in the area of noble metal catalysis.  相似文献   
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The placenta is an endocrine fetal organ, which secretes a plethora of steroid- and proteo-hormones, metabolic proteins, growth factors, and cytokines in order to adapt maternal physiology to pregnancy. Central to the growth of the fetus is the supply with nutrients, foremost with glucose. Therefore, during pregnancy, maternal insulin resistance arises, which elevates maternal blood glucose levels, and consequently ensures an adequate glucose supply for the developing fetus. At the same time, maternal β-cell mass and function increase to compensate for the higher insulin demand. These adaptations are also regulated by the endocrine function of the placenta. Excessive insulin resistance or the inability to increase insulin production accordingly disrupts physiological modulation of pregnancy mediated glucose metabolism and may cause maternal gestational diabetes (GDM). A growing body of evidence suggests that this adaptation of maternal glucose metabolism differs between pregnancies carrying a girl vs. pregnancies carrying a boy. Moreover, the risk of developing GDM differs depending on the sex of the fetus. Sex differences in placenta derived hormones and bioactive proteins, which adapt and modulate maternal glucose metabolism, are likely to contribute to this sexual dimorphism. This review provides an overview on the adaptation and maladaptation of maternal glucose metabolism by placenta-derived factors, and highlights sex differences in this regulatory network.  相似文献   
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TLRs are important receptors of cells of the innate immune system since they recognize various structurally conserved molecular patterns of different pathogens as well as endogenous ligands. In cancer, the role of TLRs is still controversial due to findings that both regression and progression of tumors could depend on TLR signaling. In the present study, M13SV1-EGFP-Neo human breast epithelial cells, MDA-MB-435-Hyg human breast cancer cells and two hybrids M13MDA435-1 and -3 were investigated for TLR4 and TLR9 expression and signaling. RT-PCR data revealed that LPS and CpG-ODN induced the expression of pro-inflammatory cytokines, like IFN-β, TNF-α, IL-1β and IL-6 in hybrid cells, but not parental cells. Interestingly, validation of RT-PCR data by Western blot showed detectable protein levels solely after LPS stimulation, suggesting that regulatory mechanisms are also controlled by TLR signaling. Analysis of pAKT and pERK1/2 levels upon LPS and CpG-ODN stimulation revealed a differential phosphorylation pattern in all cells. Finally, the migratory behavior of the cells was investigated showing that both LPS and CpG-ODN potently blocked the locomotory activity of the hybrid cells in a dose-dependent manner. In summary, hybrid cells exhibit differential TLR4 and TLR9 signaling.  相似文献   
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