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571.
In this reply, the authors point out that the simulations reported by S. M. Kanne, D. A. Balota, D. H. Spieler, and M. E. Faust (1998) did not incorporate mechanisms proposed to explain set size effects in J. D. Cohen, K. Dunbar, and J. L. McClelland (1990). The authors report a new simulation that incorporates these mechanisms and more accurately simulates S. M. Kanne et al.'s empirical data. The authors then point to other factors that could be explored in a more complete test of their model. The use of feed-forward rather than recurrent inhibition is discussed as a potentially important limitation of their original model, and recent work addressing this issue is described. The authors also discuss possible differences between word reading and color naming in the Stroop task. Although such differences may exist, the authors retain their earlier view that such differences do not reflect a dichotomy between automatic and controlled processing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
572.
The solution structure of the 64 residue structured domain (residues20–83) of barley serine proteinase inhibitor 2 (BSPI-2)is determined on the basis of 403 interproton distance, 34 øbackbone torsion angle and 26 hydrogen bonding restraints derivedfrom n.m.r. measurements. A total of 11 converged structureswere computed using a metric matrix distance geometry algorithmand refined by restrained molecular dynamics. The average rmsdifference between the final 11 structures and the mean structureobtained by averaging their coordinates is 1.4±0.2 Åfor the backbone atoms and 2.1±0.1 A for all atoms. Theoverall structure, which is almost identical to that found byX-ray crystallography, is disc shaped and consists of a centralfour component mixed parallel and antiparallel ß-sheetflanked by a 13 residue helix on one side and the reactivesite loop on the other.  相似文献   
573.
In a variety of systems, histone mRNA has been shown to lack poly(A) (Adesnik and Darnell, 1972; Grunstein et al., 1973). We have found, however, that in Xenopus laevis oocytes, poly (A)-containing mRNA codes for histones, in a wheat germ cell-free system, based on the following criteria: first, co-migration with authentic X. laevis oocyte histones on polyacrylamide gels; second, no detectable incorporation of tryptophan; third, differential incorporation of lysine and methionine into histone fraction H2A; fourth, resistance of histone fraction H2A to cleavage with cyanogen bromide; and fifth, correspondence of tryptic peptide maps of partially purified cell-free products with authentic X. laevis oocyte histone. RNA which directs the synthesis of histones in the cell-free system is retained on oligo(dT)-cellulose, even after denaturation in 80% DMSO at 70 degrees C, thereby demonstrating the covalent attachment of polyadenylic acid sequences to the mRNA. Poly (A)- RNA (7S-14S fraction) was also found to code for histones using the same criteria. We discuss the significance of the finding that X. laevis oocytes contain two classes of histone mRNA as well as the potential developmental implications of this observation.  相似文献   
574.
A method is described for the determination of unsaponifiable matter in fatty acids and mixtures of fatty and rosin acids by the use of a mixed bed ion-exchange resin.  相似文献   
575.
Composite materials from thermoplastic polyurethanes (TPUs) with biodegradable segments and microfibrillated cellulose (MFC) were developed as alternatives to traditional materials used in packaging or biomedical applications. Two TPUs were synthesized by the prepolymer method starting from different soft segments, poly(ε-caprolactone)/poly(butylene adipate) (PUBA) or poly(ε-caprolactone)/poly(ethylene oxide) (PUEO), and isophorone diisocyanate/aliphatic chain extender. Proton nuclear magnetic resonance (1H NMR) confirmed the structure and Fourier transform infrared spectroscopy (FTIR) along with scanning electron microscopy showed that the soft segments with different hydrophobicity led to a higher phase mixing in PUBA and improved microphase separation in PUEO. MFC was added in the TPUs with different soft segments to increase biocompatibility, strength, and degradation rate. A better thermal stability, a gradual increase of crystallinity and a better dispersion of MFC were noticed in PUEO composites compared to PUBA ones. The crystallinity increased with 78% and 50% in PUBA and PUEO composites with 5 wt% MFC compared to the neat polyurethanes showing the nucleating ability of MFC. In addition, the enhanced storage modulus, with 75% and 25% in PUEO and PUBA composites, highlighted the reinforcing efficiency of MFC. Therefore, the addition of MFC to the already synthesized TPUs allows tailoring the morphology and thermal properties of TPUs for industrial application.  相似文献   
576.
This paper provides the first comprehensive evaluation and analysis of modern (deep-learning-based) unsupervised anomaly detection methods for chemical process data. We focus on the Tennessee Eastman process dataset, a standard litmus test to benchmark anomaly detection methods for nearly three decades. Our extensive study will facilitate choosing appropriate anomaly detection methods in industrial applications. From the benchmark, we conclude that reconstruction-based methods are the methods of choice, followed by generative and forecasting-based methods.  相似文献   
577.
578.
Combining verification methods developed separately for software and hardware is motivated by the industry's need for a technology that would make formal verification of realistic software/hardware co-designs practical. We focus on techniques that have proved successful in each of the two domains: BDD-based symbolic model checking for hardware verification and partial order reduction for the verification of concurrent software programs. In this paper, we first suggest a modification of partial order reduction, allowing its combination with any BDD-based verification tool, and then describe a co-verification methodology developed using these techniques jointly. Our experimental results demonstrate the efficiency of this combined verification technique, and suggest that for moderate–size systems the method is ready for industrial application.  相似文献   
579.
The properties of ZnO/MgZnO heterostructures grown by pulsed-laser deposition on sapphire (112?0) and ZnO (0001?) have been compared. Electron accumulation layers have been observed for ZnO/MgZnO heterostructures grown on sapphire by capacitance-voltage (C-V) spectroscopy. The formation of a two-dimensional electron gas (2DEG) in these structures has been confirmed by temperature dependent Hall effect measurements. From C-V measurements the sheet carrier density in a Zn0.8 Mg0.2O/ZnO/Zn0.8 Mg0.2O quantum well (QW) structure with a well width of about 5 nm is calculated to be only about 9.0 × 1010 cm− 2. For the films deposited on sapphire 2D growth is observed in the Burton-Cabrera-Frank mode, as confirmed by atomic force microscopy. Step flow growth mode was achieved for the homoepitaxial thin films. Quantum confinement effects have been confirmed by photoluminescence (PL) measurements. Homoepitaxial QWs are more homogeneous (smaller inhomogeneous recombination broadening) than heteroepitaxial QWs.  相似文献   
580.
Podoplanin and Ki-67 are two important markers of cancer progression. The aim of this study is to evaluate double immunostaining for Ki-67 and podoplanin in head and neck squamous cell carcinoma (HNSCC), and to observe the involvement of lymphagiogenesis in tumoral and peritumoral areas, as well as the density of tumor proliferation correlated with histopathological grading. A total of 50 patients with HNSCC were included in this study. We carried out a morphological evaluation of tissue samples, after that, cases were selected for double Ki-67 and podoplanin immunostaining. Podoplanin expression was significantly correlated with histopathological grade (p < 0.05; p = 0.037) and expression of Ki-67 (p < 0.05; p = 0.050). A high expression of podoplanin, as well as of the proliferation factor Ki-67, was observed in histopathological grade G3 and the correlation between these (p < 0.05; p = 0.028), and implication of LMVD and LVI was not significant (LMVD p = 0.577; LVI p = 0.976). This study demonstrated the importance of double immunolabeling in assessing lymphagiogenesis and tumor proliferation in correlation with histopathological grades in HNSCC.  相似文献   
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