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161.
Rizzo Lydia; Danion Jean-Marie; Van Der Linden Martial; Grangé Danielle; Rohmer Jean-Georges 《Canadian Metallurgical Quarterly》1996,10(3):376
A group of 33 patients with schizophrenia were compared with control participants using a spatial memory task in which words were presented on locations of a grid. In the first part of the experiment, recognition of target information (words) was tested. In the second, 2 tasks of spatial location (contextual information) were given involving different sets of words placed in different locations: A location memory task (determining which word was in a particular spatial location) explored an associative form of spatial memory, and a relocation task (determining where a particular word was located) explored an associative and a nonassociative form of spatial memory. Patients were more impaired with regard to the location memory task than to the target recognition and relocation tasks. The impairment was negatively correlated with Stroop task performance. The results suggest that schizophrenia is associated with a spatial context memory deficit, which could be due to defective associations between target and spatial information. This deficit seemed to be related to frontal dysfunction. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
162.
Direct synthesis of dimethyl carbonate with supercritical carbon dioxide: Characterization of a key organotin oxide intermediate 总被引:2,自引:0,他引:2
Danielle Ballivet-Tkatchenko Stphane Chambrey Riitta Keiski Rosane Ligabue Laurent Plasseraud Philippe Richard Helka Turunen 《Catalysis Today》2006,115(1-4):80-87
The direct synthesis of dimethyl carbonate (DMC) using carbon dioxide as solvent and reagent for its fixation to methanol was explored with di-n-butyldimethoxystannane in order to get insight into the reaction mechanism for activity improvement. Catalytic runs including recycling experiments allowed isolation and characterization by NMR, IR, and single-crystal X-ray diffraction of a new tin complex containing 10 tin atoms. This compound could be prepared independently and is considered as a resting species. The yield of DMC is highest under 20 MPa pressure that fits with a monophasic supercritical medium in agreement with fluid phase equilibria calculations. In line, preliminary kinetics and initial rate determination show a positive order in carbon dioxide and a first-order dependence on the stannane. The initial rates were lower with the deca-tin complex than with the stannane precursor, but the turnover numbers (TONs) were higher. Water, the co-product of the reaction, was found to reversibly poison the active centers. Its in situ trapping had a beneficial effect. This study provides new mechanistic clues as to the reactive species and DMC formation. Further kinetics work is in progress to determine the rate-limiting step(s) at the initial stage of the reaction for more active catalyst design. 相似文献
163.
N Leblanc C Roux JM Pradier C Perrot-Rechenmann 《Canadian Metallurgical Quarterly》1997,33(4):679-689
The isolation and the characterization of two tobacco cDNAs, Nt-ERabp1 and Nt-ERabp2, homologous to Zm-ERabp1, encoding the major auxin-binding protein from maize coleoptiles, are described. Their predicted amino acid sequences correspond to proteins of ca. 21 kDa, in which the characteristic regions common to ABP1-related polypeptides are well-conserved. Southern analysis indicates that the genes corresponding to Nt-ERabp1 cDNA and Nt-ERabp2 cDNA derive respectively from Nicotiana tomentosiformis and Nicotiana sylvestris, the diploid progenitors of Nicotiana tabacum. Analysis of mRNA distribution in tobacco plants indicates that these two genes are preferentially expressed in flowers and growing seedlings. Whatever the tissue tested, Nt-ERabp1 mRNA is more abundant than Nt-ERabp2 mRNA. Furthermore, RT-PCR reveals developmental and organ-specific expression of these two genes in flower parts of tobacco plants. In particular, regulation of Nt-ERabp1 mRNA accumulation appears to be correlated with elongation growth of each floral organ. Recombinant Nt-ERabp1, produced in Escherichia coli, is recognized by antibodies raised against Zm-ERabp1. 相似文献
164.
Danielle M. Tahan Ahmad Safari Lisa C. Klein 《Journal of the American Ceramic Society》1996,79(6):1593-1598
Barium strontium titanate, (Bax ,Sr1-x TiO3 , thin films of various compositions were prepared by a sol-gel method. Solutions consisting of acetate powders and titanium IV isopropoxide in a mixture of acetic acid and ethylene glycol were spin-coated onto silicon and platinum-coated silicon substrates. Processing parameters were optimized to develop stable solutions which yielded films with relatively low crystallization temperatures. It was determined that ethylene glycol was a necessary component of the solution to increase stability to precipitation and to decrease the crystallization temperature of the films. The grain size of the films varied with annealing temperature and atmosphere and directly affected the dielectric properties. A dielectric constant of 400 and a dissipation factor of 0.04 were measured at 1 kHz for (Ba0.8 ,Sr0.2 ) TiO3 films heated to 700°C for 1 h with a thickness of approximately 400 nm. Films of this composition maintained low leakage current densities for extended time periods when measured at an applied field of 75 kV/cm. 相似文献
165.
Julien Danielle; Mergler Donna; Baldwin Mary; Sassine Marie-Pascale; Cormier Nathalie; Chartrand élise; Bélanger Suzanne 《Canadian Metallurgical Quarterly》1998,30(3):147
55 workers and their spouses took part in assessment of the effect of exposure to nerve agents in the workplace on mental health and marriage. Standardized measurements were used to assess exposure level, mental health problems and marital discord. Significant levels of exposure were related to a high incidence of psychological symptoms. Workers' psychological symptoms mediated the impact of exposure on spouses' perceptions of marital discord. Exposure regulated the related the relationship between mental health and marital discord. Exposure therefore posed a risk to marital stability. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
166.
A wavelength-division-multiplexing transmission experiment using a 1300/1500 nm dual-wavelength LED modulated at 140/560 Mbit/s over 10 km of single-mode fibre has been demonstrated. This dual-LED device has a 9 ?m emitter spacing between the active facets with a coupling loss of 2.3 dB through a lens/fibre coupler. The chromatic dispersion penalty for the 1500 nm channel at 560 Mbit/s was about 6-5 dB and the electrical crosstalk penalty was 2.5 dB. 相似文献
167.
168.
Chuck muscles from 24 beef carcasses electrically stimulated (ES) with either high or low voltage, or a combination of both, and submitted to conventional or rapid chilling regimes were used in a model system study (pH, salt-solubloe protein extraction, emulsifying capacity) and in frank-further fabrication and analysis (yield, color, texture). Glycolytic rates measured in the loin had no effects on the functional parameters or on the quality of frankfurters. The ultimate pH values of unstimulated carcasses remained higher than in any ES carcasses, and led to higher protein extraction (P ≤ 0·05). However, ES had no further influence on the emulsifying capacity or on frankfurter yield and quality parameters independently of the voltage used (P > 0·05). Chilling regimes had no influence on the functional parameters of the model system but slightly influenced the yield and chewiness of the frankfurters (P ≤ 0·05). Therefore, the use of any type of ES in combination with either conventional (Canadian) or more rapid chilling is unlikely to have commercial significance on the yield or quality of frankfurters. 相似文献
169.
Danielle Ezuz Justin Solomon Vladimir G. Kim Mirela Ben-Chen 《Computer Graphics Forum》2017,36(5):49-57
Deep neural networks provide a promising tool for incorporating semantic information in geometry processing applications. Unlike image and video processing, however, geometry processing requires handling unstructured geometric data, and thus data representation becomes an important challenge in this framework. Existing approaches tackle this challenge by converting point clouds, meshes, or polygon soups into regular representations using, e.g., multi‐view images, volumetric grids or planar parameterizations. In each of these cases, geometric data representation is treated as a fixed pre‐process that is largely disconnected from the machine learning tool. In contrast, we propose to optimize for the geometric representation during the network learning process using a novel metric alignment layer. Our approach maps unstructured geometric data to a regular domain by minimizing the metric distortion of the map using the regularized Gromov–Wasserstein objective. This objective is parameterized by the metric of the target domain and is differentiable; thus, it can be easily incorporated into a deep network framework. Furthermore, the objective aims to align the metrics of the input and output domains, promoting consistent output for similar shapes. We show the effectiveness of our layer within a deep network trained for shape classification, demonstrating state‐of‐the‐art performance for nonrigid shapes. 相似文献
170.
Insights from NMR Spectroscopy into the Conformational Properties of Man‐9 and Its Recognition by Two HIV Binding Proteins
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Dr. Syed Shahzad‐ul‐Hussan Dr. Mallika Sastry Dr. Thomas Lemmin Dr. Cinque Soto Dr. Sandra Loesgen Dr. Danielle A. Scott Dr. Jack R. Davison Dr. Katheryn Lohith Dr. Robert O'Connor Dr. Peter D. Kwong Dr. Carole A. Bewley 《Chembiochem : a European journal of chemical biology》2017,18(8):764-771
Man9GlcNAc2 (Man‐9) present at the surface of HIV makes up the binding sites of several HIV‐neutralizing agents and the mammalian lectin DC‐SIGN, which is involved in cellular immunity and trans‐infections. We describe the conformational properties of Man‐9 in its free state and when bound by the HIV entry‐inhibitor protein microvirin (MVN), and define the minimum epitopes of both MVN and DC‐SIGN by using NMR spectroscopy. To facilitate the implementation of 3D 13C‐edited spectra to deconvolute spectral overlap and to determine the solution structure of Man‐9, we developed a robust expression system for the production of 13C,15N‐labeled glycans in mammalian cells. The studies reveal that Man‐9 interacts with HIV‐binding proteins through distinct epitopes and adopts diverse conformations in the bound state. In combination with molecular dynamics simulations we observed receptor‐bound conformations to be sampled by Man‐9 in the free state, thus suggesting a conformational selection mechanism for diverse recognition. 相似文献