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The utilisation of oligosaccharides by oral microorganisms and intestinal enzymes are important factors in determining their effectiveness as alternative sweeteners. In this study, classes of naturally occurring sugars were assessed using in vitro models for oral and intestinal digestibility, in order to test the influence of chemical structure on functional properties. Amongst the classes of sucrose isomers, α-glucobioses, β-glucobioses and sucrose-based oligosaccharides, structures were identified that were not utilised by the common oral bacterium Streptococcus mutans, and would therefore contribute to the non-cariogenic potential of a sweetener. Analysis of the rate and products of digestion by a rat glucosidase mixture was used to determine the relative intestinal digestibility. The results showed that oligosaccharides containing a (1 → 6)-β-Glc group, including gentiobiose and gentiobiitol, together with melezitose, a sucrose-derived oligosaccharide containing a α-Glc-(1 → 3)-Fru moiety were resistant to digestion by both S. mutans and mammalian intestinal enzymes, highlighting their potential as dietary sugar substitutes.  相似文献   
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Resident democracy as a special form of participatory democratic set-up is fundamental in the understanding, and self-understanding, of the non-profit housing sector in Denmark. Through a case study, the paper explores how resident democracy is perceived and narrated between residents and employees at a housing association. The study indicates that the meta-story of democracy is disconnected from practice and the lived lives of residents. Three analytical tensions structure the analysis, which relate to the conditions for realizing the democratic ideal embedded in the structure of the sector. The tensions are related to representative versus participatory democracy; collectivity versus individuality; and service versus welfare. The tensions elucidate how resident democracy is squeezed between different logics, which result in an ambiguous setting for practising democracy. Based on the results, the article discusses conditions for prospective democracy in the Danish non-profit housing sector.  相似文献   
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We have defined the Cassiopeia method, whose specificity is to focus the analysis and design of a multiagent system on the notion of organization. This article reports the use of this methodological framework for designing and implementing the organization of a robot soccer team in the context of a research project on collective robotics. We show why we chose this application, and we discuss its interest and inherent difficulties, in order to clearly express the needs for a design methodology dedicated to distributed artificial intelligence.  相似文献   
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The role of the synaptic vesicle protein 2A (SV2A) protein, target of the antiepileptic drug levetiracetam, is still mostly unknown. Considering its potential to provide in vivo functional insights into the role of SV2A in epileptic patients, the development of an SV2A positron emission tomography (PET) tracer has been undertaken. Using a 3D pharmacophore model based on close analogues of levetiracetam, we report the rationale design of three heterocyclic non‐acetamide lead compounds, UCB‐A, UCB‐H and UCB‐J, the first single‐digit nanomolar SV2A ligands with suitable properties for development as PET tracers.  相似文献   
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