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21.
The Council of the European Union has proposed a revision on the EU regulation on novel foods and novel food ingredients concerning safety assessment of traditional foods from non-EU countries and their introduction onto the EU market. The proposal stipulates that such foods may be placed on the EU market if their history of safe use in the country of origin is appropriately documented. The present statement of the SKLM gives an overview on current discussions on practical implementation of the "history of safe use" concept as well as examples of its application. The SKLM, in principle, agrees with these concepts, underscores, however, in connection with convincing evidence for a "history of safe use" the need for a range of additional information to achieve a comprehensive risk assessment. In the opinion of the SKLM such information must comprise compositional data as well as experience on adverse effects. A list of questions considered essential is presented. The following opinion was adopted on December 23rd 2010.  相似文献   
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Used correlation functions obtained in 2 experiments with undergraduate Os (N = 10) as a basis for describing human visual letter recognition. Visual images were filtered by means of autocorrelation for pattern information. This operation gave the relative visibilities or legibilities of the characters. The visual impressions were then cross-correlated with a set of memory records whose outputs described the relative probabilities that the stimulus was a given character. This operation described confusion errors. Finally "response bias" was described in terms of the reliability with which a memory record provides identification of a given stimulus. In these terms response bias represented an attempt by the recognition system to minimize errors in high-information responses, at the expense of producing more low-information responses as errors. (French summary) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Objective: To develop and evaluate a new pediatric measure of community integration: the Pediatric Community Participation Questionnaire (PCPQ). Participants: 105 youths with physical disabilities. Measures: In addition to the PCPQ, demographic and disability-related questions and the Functional Disability Inventory (FDI) were administered. Results: The PCPQ demonstrated convergent validity through its high association with functional ability, discriminant validity through its ability to discriminate between ambulatory and nonambulatory participants, and excellent internal consistency. Conclusions: Community participation, an important component of positive overall development, may be particularly important for youths with physical disabilities. The findings from this study provide preliminary support for the validity and reliability of the PCPQ, supporting its use as a measure of community participation with this population. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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In an earlier paper the authors discussed numerical methods of contact stress analysis for rigid indenters pressed against rough elastic slabs. In this sequel, they include the deformation of the cylindrical indenter using numerical methods of analysis similar to those adopted in the previous article. Examples which demonstrate the effects of indenter deformation and adhesion in the contact area are presented.  相似文献   
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To determine the capillary gas chromatographic (GC) elution order of the enantiomers of 4-mercapto-2-alkanones, racemic 4-acetylthio-2-alkanones were synthesized and hydrolyzed by lipases to get enantio-enriched 4-mercapto-2-alkanones that were resolved by capillary gas chromatography using a chiral stationary phase. The obtained enantio-enriched 4-mercapto-2-alkanones were esterified with (S)-2-methoxy-2-(1-naphthyl)propionic acid ((S)-MαNP acid), and the HPLC analysis of MαNP thioesters revealed the same isomeric ratios as the chiral GC analysis of the corresponding thiol enantiomers. The diastereoisomeric thioesters obtained were resolved by HPLC, and the absolute configurations were determined on the basis of 1H NMR anisotropy effects. On the basis of these results, the GC elution order of the enantiomers of 4-mercapto-2-alkanones and of the corresponding 4-acetylthio-2-alkanones could be determined. The combination of enzymatic resolution and MαNP thioesterification proved to be a useful tool to determine the absolute configuration of secondary thiols.  相似文献   
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A. Ohlhoff  H. Engel   《Catalysis Today》2001,70(4):1249-368
We consider the CO oxidation in a continuous-flow reactor containing N catalytic layers of zeolite-supported palladium. For the kinetics of the reaction in one layer, we adopt a model proposed by Slin’ko and Jaeger. Rather than studying non-uniform coverage patterns on the individual catalyst layers, we focus on the influence of flow-mediated spatial coupling between the layers provided by variations in the CO partial pressure, which are transmitted by the flow to the adjacent downstream layer. Using the flow rate and the CO partial pressure at the inlet of the reactor as bifurcation parameters, in a parameter range where the reaction in one layer exhibits relaxational rate oscillations, we find different modes of operation for the reactor. The bifurcation diagram for two layers exhibits synchronized behavior at large flow rate. At lower flow rate and small CO partial pressure, we obtain a drop of catalytic activity at the first layer followed by a compensating increase at the second layer. In the multi-layer system, an increasing number of layers works synchronously when the flow rate grows up. Then, downstream and upstream moving pulse trains of catalytic activity can develop.  相似文献   
29.
Small hydrophobic ligands identifying intracellular protein deposits are of great interest, as protein inclusion bodies are the pathological hallmark of several degenerative diseases. Here we report that fluorescent amyloid ligands, termed luminescent conjugated oligothiophenes (LCOs), rapidly and with high sensitivity detect protein inclusion bodies in skeletal muscle tissue from patients with sporadic inclusion body myositis (s‐IBM). LCOs having a conjugated backbone of at least five thiophene units emitted strong fluorescence upon binding, and showed co‐localization with proteins reported to accumulate in s‐IBM protein inclusion bodies. Compared with conventional amyloid ligands, LCOs identified a larger fraction of immunopositive inclusion bodies. When the conjugated thiophene backbone was extended with terminal carboxyl groups, the LCO revealed striking spectral differences between distinct protein inclusion bodies. We conclude that 1) LCOs are sensitive, rapid and powerful tools for identifying protein inclusion bodies and 2) LCOs identify a wider range of protein inclusion bodies than conventional amyloid ligands.  相似文献   
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On‐line liquid chromatography‐gas chromatography (LC‐GC) has been applied to the detection of vegetable oils in milk fat using β‐sitosterol as marker. The method involves transesterification of the fat, pre‐separation of the sterol fraction from other lipid constituents and on‐line transfer to the capillary GC system. The on‐line approach avoids time‐consuming sample preparation steps prior to GC analysis. The suitability of this analytical approach was tested with model mixtures of milk fat with cotton and rapeseed oil. The method allows the detection of adulterations at low levels. Simultaneous quantification of cholesterol in milk fat is also possible. Considering the rapid sample preparation, the described method can be applied for screening of large sample numbers.  相似文献   
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