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61.
Ladouceur Robert; Ferland Francine; Poulin Christiane; Vitaro Frank; Wiebe Jamie 《Canadian Metallurgical Quarterly》2005,19(3):271
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
62.
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
63.
Red Fluorescent Turn‐On Ligands for Imaging and Quantifying G Protein‐Coupled Receptors in Living Cells
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Iuliia A. Karpenko Rémy Kreder Christel Valencia Dr. Pascal Villa Dr. Christiane Mendre Dr. Bernard Mouillac Prof. Dr. Yves Mély Prof. Dr. Marcel Hibert Dr. Dominique Bonnet Dr. Andrey S. Klymchenko 《Chembiochem : a European journal of chemical biology》2014,15(3):359-363
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
64.
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
65.
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
66.
67.
The characterization of cord blood hemoglobin at the molecular level is a daunting challenge because hemoglobin F (HbF) and hemoglobin A (HbA) coexist in neonatal blood. We developed and validated a method using electrospray time-of-flight mass spectrometry (ES-TOF-MS) that measures, in a single analysis, relative levels of glycated and acetylated hemoglobin and allows the calculation of relative proportions of HbA, HbF(0), and HbF(1) in cord blood. Specific sections of acquired spectra were deconvoluted using a maximum entropy-based approach to true mass scale spectra. Mass precisions were less than 3 ppm with similar accuracies. Intra-interday precisions for α- and γ-chain glycation levels were 2.10%/3.72% and 2.75%/6.79%, respectively. The linearity of the α-chain glycation response was excellent (r(2) = 0.9990). We performed sample analysis on 39 cord blood specimens and found that the glycated α- and γ-chain levels were 2.27 ± 0.21% and 2.38 ± 0.29%, respectively, while the acetylated (G)γ and (A)γ-chain levels were 8.48 ± 0.53% and 7.14 ± 0.74%, respectively. We observed three types of HbF distinguishable by the intensities of γ-chain variants. Two-thirds of cord blood specimens were classified as HbF(I) with an intensity ratio (G)γ/(A)γ of 1.90 ± 0.12. For HbF(II) type (10/39 neonates), the intensity ratio of (G)γ/(A)γ was 3.71 ± 0.28. For three neonates with HbF(III), no (A)γ-chain was detected. 相似文献
68.
Organic layers can be used to realize special functions in optical interference coatings. Suitable compounds for such layers were thermally evaporated and characterized. A plasma etching procedure was applied to produce nanostructures on top of the organic layers to reduce their effective refractive indices. Broadband antireflective coatings were obtained by combining these artificial low-index layers with conventionally prepared interference stacks. 相似文献
69.
Zhai YH Goulart C Sharping JE Wei H Chen S Tong W Slipchenko MN Zhang D Cheng JX 《Applied physics letters》2011,98(19):191106
We report on multimodal coherent anti-Stokes Raman scattering (CARS) imaging with a source composed of a femtosecond fiber laser and a photonic crystal fiber (PCF)-based optical parametric oscillator (FOPO). By switching between two PCFs with different zero dispersion wavelengths, a tunable signal beam from the FOPO covering the range from 840 to 930 nm was produced. By combining the femtosecond fiber laser and the FOPO output, simultaneous CARS imaging of a myelin sheath and two-photon excitation fluorescence imaging of a labeled axons in rat spinal cord have been demonstrated at the speed of 20 μs per pixel. 相似文献
70.
The effect of stock-culture period on the sensitivity of theLemna bioassay to four different phenolic substances was evaluated in this study. The sensitivity of the bioassay interacted with the stock-culture period of either 11, 14, or 18 days. After a seven-day testp-hydroxybenzoic acid (HBA), vanillic acid (VA),trans-cinnamic acid (CA), and ferulic acid (FA) with a concentration of 0.05 mM significantly reduced the number of fronds and the dry weight compared with the untreated control when the stock-culture period had been exactly 14 days. The sensitivity after the shorter (11 days) or longer (18 days) stock-culture period was reduced, and the differences in the dry weight to the untreated control were not significant after a stock culture period of 18 days. The two higher concentrations (0.1 and 0.25 mM) showed stronger inhibition. A comparison of the inhibition at 0.05 mM revealed that the stock-culture period affected the relative toxicity of the four phenolic substances. Since the pH increased in the stock-culture flasks during the 18-day period from 6.25 to 7.9, we hypothesize that differences in theLemna assay can be at least partly attributed to a pH effect, possibly in combination with a relative nutrient deficiency. We recommend a standardization of the stock-culture period to 14 days to improve the sensitivity of theLemna bioassay. 相似文献