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 Two HPLC methods with diode array detection were used to separate Maillard products from milk components. The Maillard products 4-(β-d-galactopyranosyloxy)-2-hydroxy-2-methyl-2H-pyran-3(6H)-one (2), 1-[3-(β-d-galactopyranosyloxy)-2-furanyl]-1-ethanone (4), 4-(β-d-galactopyranosyloxy)-5-(hydroxymethyl)-2-methyl-3(2H)-furanone (5), isomaltol (7), maltol (9), 2,3-dihydro-3,5-dihydroxy-6-methyl-4H-pyran-4-one (6), and 5-hydroxymethyl-2-furfuraldehyde (8) were determined using a water-methanol gradient. Furthermore, 4,5-dihydroxy-2-(β-d-galactopyranosyloxy)-5-methyl-2-cyclopenten-1-one (3) was separated from the milk components by applying the interaction reagent octylamine. Several heated or processed milk samples were analyzed, and formation of the Maillard products was determined and quantified. Thus it was found that 2 and 3 are early products of the Maillard reaction in milk, whereas after prolonged heating 4, 5, and particularly 9 and 6 become more important. Compounds 7 and 8 were not detected, even if the samples were heated under stringent conditions.  相似文献   
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This study assessed the possible differences in the classification of adolescent gamblers when using the South Oaks Gambling Screen-Revised for Adolescents (SOGS-RA; K. C. Winters, R. D. Stinchfield, & J. Fulkerson, 1993) versus a clinical interview that was based on Diagnostic and Statistical Manual of Mental Disorders (DSM-IV; American Psychiatric Association, 1994) criteria for pathological gambling. A total of 631 adolescents ages 15-17 years participated in the two phases of the study. Results revealed that of the 93 adolescents who had been screened as problem gamblers according to the SOGS-RA, only 7 could be clinically confirmed as pathological gamblers according to the criteria used at present to define pathological gambling. The need to clarify the construct of pathological gambling among youth is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Mit Einführung eines Dokumentmanagement-und Vorgangsbearbeitungssystems (DMS) muss sich die Verwaltung der Herausforderung der automatisiert erfolgenden Protokollierung stellen. An einem DMS zeigt sich u.a. sehr deutlich, dass verschiedene Typen von Protokolldaten zu unterscheiden sind.  相似文献   
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Classical fluorescence‐based approaches to monitor ligand–protein interactions are generally hampered by the background signal of unbound ligand, which must be removed by tedious washing steps. To overcome this major limitation, we report here the first red fluorescent turn‐on probes for a G protein‐coupled receptor (oxytocin receptor) at the surface of living cells. The peptide ligand carbetocin was conjugated to one of the best solvatochromic (fluorogenic) dyes, Nile Red, which turns on emission when reaching the hydrophobic environment of the receptor. We showed that the incorporation of hydrophilic octa(ethylene glycol) linker between the pharmacophore and the dye minimized nonspecific interaction of the probe with serum proteins and lipid membranes, thus ensuring receptor‐specific turn‐on response. The new ligand was successfully applied for background‐free imaging and quantification of oxytocin receptors in living cells.  相似文献   
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In computational systems biology, the general aim is to derive regulatory models from multivariate readouts, thereby generating predictions for novel experiments. In the past, many such models have been formulated for different biological applications. The authors consider the scenario where a given model fails to predict a set of observations with acceptable accuracy and ask the question whether this is because of the model lacking important external regulations. Real‐world examples for such entities range from microRNAs to metabolic fluxes. To improve the prediction, they propose an algorithm to systematically extend the network by an additional latent dynamic variable which has an exogenous effect on the considered network. This variable''s time course and influence on the other species is estimated in a two‐step procedure involving spline approximation, maximum‐likelihood estimation and model selection. Simulation studies show that such a hidden influence can successfully be inferred. The method is also applied to a signalling pathway model where they analyse real data and obtain promising results. Furthermore, the technique can be employed to detect incomplete network structures.Inspec keywords: biology computing, RNA, splines (mathematics), maximum likelihood estimation, approximation theory, biochemistryOther keywords: latent dynamic components, biological systems, computational system biology, regulatory models, multivariate readouts, biological applications, external regulations, real‐world examples, microRNA, metabolic fluxes, latent dynamic variables, variable time course, two‐step procedure, spline approximation, maximum‐likelihood estimation, model selection, signalling pathway model, real data, incomplete network structures  相似文献   
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Combining environmental with employment objectives, ecological tax reform (ETR) envisages a double dividend. While research has mainly focused on the socio-economic and environmental impacts of ETR, there is less literature on the social responses. This paper gives an overview and history of German ETR as well as investigating the understanding of perceptions and attitudes towards ETR of those being “subject to tax”. The research is based on qualitative social research methods. As with the other PETRAS papers, interviews were conducted with policy-makers and business leaders and focus groups were formed with lay persons. The results show that responses of policy-makers and business leaders are modest. Although some criticisms about the specific design of the German ETR remain, complaints towards ETR are settled. Attitudes appear influenced by more fundamental convictions such as economic interest or altruistic views. In contrast, ETR appears to politicise common people. Attitudes are influenced by the overall comprehension of the ETR concept, the expected impacts, perceived information deficits, as well as a general distrust in politics. Our data show that the linking of environmental and employment objectives is not understood and not welcomed. In order to increase social acceptance, the paper discusses refocusing ETR on environmental objectives, modestly increasing the share of ETR revenue spent for environmental purposes, removing inconsistencies in the ETR design, and improving information policy.  相似文献   
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