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21.
Corneille Olivier; Huart Johanne; Becquart Emilie; Brédart Serge 《Canadian Metallurgical Quarterly》2004,86(2):236
In 4 studies, the authors examined the impact of categorization on the recollection of ethnically ambiguous faces. Participants were presented with faces lying at various locations on mixed-race continua (i.e., Caucasian-North African and Caucasian-Asian faces were used as source images in a morphing program). In all studies, the prevalence of exclusive ethnic features in a face distorted participants' recollections of the face toward faces more typical of the category. Specifically, the recollection of 30% North African (or 30% Asian) faces shifted toward Caucasian source faces, whereas the recollection of 70% North African (or 70% Asian) faces shifted toward North African (Asian) source faces. Memory distortions did not emerge for extremely ambiguous (50%) faces and proved larger on mixed-race than same-race continua (Studies 3 and 4). Memory distortions also emerged with high levels of confidence. The authors elaborate on the theoretical and practical implications of these findings. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
22.
The taxation of citizens' consumption of goods and services is of great importance for government revenue worldwide. However, the constantly growing Internet market is changing the ways in which those goods and services are acquired and consumed, making it difficult to administer and enforce existing tax rules. Tax rules, being directly connected to the government's chosen policy of raising revenue to finance its spending on the public sector, are matters of a highly sovereign nature, and their efficient working clashes with the inherently borderless and intangible nature of the Internet. New methods of delivery and new categories of products that can be delivered between jurisdictions without passing any physical borders raise particular problems for VAT purposes. To achieve the twin goals of encouraging e-commerce and protecting national revenue bases, international cooperation must be sought in the development of mechanisms to collect tax in the new digital commercial environment. Without a mutual understanding of common interests and respect for domestic tax policies, the changing dynamic in commerce to which the Internet is giving rise may prove an unbeatable barrier to the efficient working of a VAT system that guarantees fair competition between suppliers, and provides technological neutrality and equity among consumers. 相似文献
23.
GF Hankard N Brousse JP Cézard D Emilie M Peuchmaur 《Canadian Metallurgical Quarterly》1997,24(5):568-572
BACKGROUND: Eosinophils contribute to the intestinal inflammatory infiltrate in Crohn's disease (CD). Eosinophilic infiltration occurs early in Crohn's recurrences, and a release of eosinophil cationic proteins has been observed in active CD. The proliferation, differentiation, and activation of eosinophils are highly dependent on the cytokine interleukin 5 (IL5). In the present study, we used in situ hybridization (ISH) to investigate the expression of the IL5 gene in intestinal specimens from patients with CD. METHODS: We studied 14 intestinal samples from eight children who had undergone ileocolectomy for advanced CD. The samples were examined for the intensity of the inflammatory infiltrate. Normal pediatric intestine specimens served as controls. In situ hybridization was performed on frozen tissue using radiolabeled IL5 mRNA probes. RESULTS: Positive signal with the IL5 antisense probe was observed within numerous cells infiltrating the specimens involved with CD. The number of IL5-expressing cells correlated with the histological grade of inflammation. Most of the labeled cells were eosinophils, characterized by their bilobed nuclei. Rare IL5-positive cells were detected in the control tissues. No positive signal was obtained with the IL5 sense probe. CONCLUSION: These results suggest that IL5 can be produced by eosinophils at the sites of inflammation in active CD and could be involved in the immune response by activating eosinophils, at least in part through an autocrine pathway, and perhaps by interacting with B and T cells. 相似文献
24.
Binding Mode and Structure–Activity Relationships around Direct Inhibitors of the Nrf2–Keap1 Complex 下载免费PDF全文
Dr. Eric Jnoff Dr. Claudia Albrecht Dr. John J. Barker Dr. Oliver Barker Dr. Edward Beaumont Dr. Steven Bromidge Dr. Frederick Brookfield Dr. Mark Brooks Dr. Christian Bubert Dr. Tom Ceska Vincent Corden Dr. Graham Dawson Dr. Stephanie Duclos Dr. Tara Fryatt Dr. Christophe Genicot Dr. Emilie Jigorel Dr. Jason Kwong Rosemary Maghames Innocent Mushi Dr. Richard Pike Dr. Zara A. Sands Dr. Myron A. Smith Dr. Christopher C. Stimson Dr. Jean‐Philippe Courade 《ChemMedChem》2014,9(4):699-705
An X‐ray crystal structure of Kelch‐like ECH‐associated protein (Keap1) co‐crystallised with (1S,2R)‐2‐[(1S)‐1‐[(1,3‐dioxo‐2,3‐dihydro‐1H‐isoindol‐2‐yl)methyl]‐1,2,3,4‐tetrahydroisoquinolin‐2‐carbonyl]cyclohexane‐1‐carboxylic acid (compound (S,R,S)‐ 1 a ) was obtained. This X‐ray crystal structure provides breakthrough experimental evidence for the true binding mode of the hit compound (S,R,S)‐ 1 a , as the ligand orientation was found to differ from that of the initial docking model, which was available at the start of the project. Crystallographic elucidation of this binding mode helped to focus and drive the drug design process more effectively and efficiently. 相似文献
25.
Verónica López Calvo Mónica Vicent Cabedo Emilie Bannier Eugeni Cañas Recacha Aldo R. Boccaccini Luis Cordero Arias Enrique Sánchez Vilches 《Journal of Materials Science》2014,49(23):7933-7942
45S5 bioactive glass powders with the composition of 45 SiO2, 6 P2O5, 24.5 CaO and 24.5 wt% Na2O were melted and quenched in water to obtain a frit. The frit was milled using two different routes: dry milling followed by sieving to obtain glass particles and wet milling followed by spray drying to obtain a powder comprising porous agglomerates. All feedstocks showed adequate characteristics that make them suitable to be deposited by atmospheric plasma spraying. The powders and coatings were characterised by field-emission gun environmental scanning electron microscope and X-ray diffraction. The roughness and the contact angle of the coatings were also determined. The bioactivity of the powders and coatings was assessed by immersion in simulated body fluid. It was found that bioactive glass prepared from bioglass frit by dry milling exhibited similar bioactivity as that of a commercial bioactive glass. All coatings produced showed good adhesion to the substrate as well as suitable surface properties to ensure efficient contact with body fluid. Regardless of the characteristics of the feedstocks or plasma spray conditions used, all coatings were exclusively made up of an amorphous phase. On the other hand, micrographs revealed that the characteristics of the feedstock strongly impact on the final coating microstructure. The most homogeneous microstructure was obtained when the feedstock was prepared by fine dry grinding of the frit. For this coating, the formation of a bioactive layer was also proved by Fourier transform infrared spectroscopy and X-ray diffraction. 相似文献
26.
Nanoparticles: “Hyper‐bright” Near‐Infrared Emitting Fluorescent Organic Nanoparticles for Single Particle Tracking (Adv. Mater. 14/2014) 下载免费PDF全文
27.
28.
Alessandrini M Maggio S Porée J De Marchi L Speciale N Franceschini E Bernard O Basset O 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2011,58(11):2344-2360
Ultrasonic tissue characterization has become an area of intensive research. This procedure generally relies on the analysis of the unprocessed echo signal. Because the ultrasound echo is degraded by the non-ideal system point spread function, a deconvolution step could be employed to provide an estimate of the tissue response that could then be exploited for a more accurate characterization. In medical ultrasound, deconvolution is commonly used to increase diagnostic reliability of ultrasound images by improving their contrast and resolution. Most successful algorithms address deconvolution in a maximum a posteriori estimation framework; this typically leads to the solution of l(2)-norm or (1)-norm constrained optimization problems, depending on the choice of the prior distribution. Although these techniques are sufficient to obtain relevant image visual quality improvements, the obtained reflectivity estimates are, however, not appropriate for classification purposes. In this context, we introduce in this paper a maximum a posteriori deconvolution framework expressly derived to improve tissue characterization. The algorithm overcomes limitations associated with standard techniques by using a nonstandard prior model for the tissue response. We present an evaluation of the algorithm performance using both computer simulations and tissue-mimicking phantoms. These studies reveal increased accuracy in the characterization of media with different properties. A comparison with state-of-the-art Wiener and l(1)-norm deconvolution techniques attests to the superiority of the proposed algorithm. 相似文献
29.
Geosmin and 2-methylisoborneol (MIB) have been associated with off-flavour problems in fish and seafood products, generating a strong negative impact for aquaculture industries. Although most of the producers of geosmin and MIB have been identified as Streptomyces species or cyanobacteria, Streptomyces spp. are thought to be responsible for the synthesis of these compounds in indoor recirculating aquaculture systems (RAS). The detection of genes involved in the synthesis of geosmin and MIB can be a relevant indicator of the beginning of off-flavour events in RAS. Here, we report a real-time polymerase chain reaction (qPCR) protocol targeting geoA sequences that encode a germacradienol synthase involved in geosmin synthesis. New geoA-related sequences were retrieved from eleven geosmin-producing Actinomycete strains, among them two Streptomyces strains isolated from two RAS. Combined with geoA-related sequences available in gene databases, we designed primers and standards suitable for qPCR assays targeting mainly Streptomyces geoA. Using our qPCR protocol, we succeeded in measuring the level of geoA copies in sand filter and biofilters in two RAS. This study is the first to apply qPCR assays to detect and quantify the geosmin synthesis gene (geoA) in RAS. Quantification of geoA in RAS could permit the monitoring of the level of geosmin producers prior to the occurrence of geosmin production. This information will be most valuable for fish producers to manage further development of off-flavour events. 相似文献
30.
The purpose of this work consists in following the dependence of physical properties on the temperature during the compaction of an organic component. A special thermo-regulated die has been developed to realize uniaxial compression at different constant temperatures. This study has shown that a temperature change modifies the microstructures and the mechanical behaviour of the tablets. The measurement of the tablet porosity during the compression cycle allows us to conclude that temperature influences mainly the phenomena occurring during the isobaric stage of the compression cycle and not the ones during the pressure increase. On the other hand, during the pressure increase, the acoustical activity of the powder is reduced when temperature increases. The tensile strength of tablets realized at different temperatures was also studied and shows a maximum around 60 °C that can be explained by the SEM analysis of the microstructure of the tablets. 相似文献