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Neural Computing and Applications - With an increase in online longitudinal users’ interactions, capturing users’ precise preferences and giving accurate recommendations have become an... 相似文献
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Many models of spoken word recognition posit the existence of lexical and sublexical representations, with excitatory and inhibitory mechanisms used to affect the activation levels of such representations. Bottom-up evidence provides excitatory input, and inhibition from phonetically similar representations leads to lexical competition. In such a system, long words should produce stronger lexical activation than short words, for 2 reasons: Long words provide more bottom-up evidence than short words, and short words are subject to greater inhibition due to the existence of more similar words. Four experiments provide evidence for this view. In addition, reaction-time-based partitioning of the data shows that long words generate greater activation that is available both earlier and for a longer time than is the case for short words. As a result, lexical influences on phoneme identification are extremely robust for long words but are quite fragile and condition-dependent for short words. Models of word recognition must consider words of all lengths to capture the true dynamics of lexical activation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Microstrip stepped impedance resonator bandpass filter with an extended optimal rejection bandwidth 总被引:2,自引:0,他引:2
Bandpass filters with an optimal rejection bandwidth are designed using parallel-coupled stepped impedance resonators (SIRs). The fundamental (f/sub o/) and higher order resonant harmonics of an SIR are analyzed against the length ratio of the high-Z and low-Z segments. It is found that an optimal length ratio can be obtained for each high-Z to low-Z impedance ratio to maximize the upper rejection bandwidth. A tapped-line input/output structure is exploited to create two extra transmission zeros in the stopband. The singly loaded Q(Q/sub si/) of a tapped SIR is derived. With the aid of Q/sub si/, the two zeros can be independently tuned over a wide frequency range. When the positions of the two zeros are purposely located at the two leading higher order harmonics, the upper rejection band can be greatly extended. Chebyshev bandpass filters with spurious resonances up to 4.4f/sub o/, 6.5f/sub o/, and 8.2f/sub o/ are fabricated and measured to demonstrate the idea. 相似文献
6.
Cell cycle-dependent tumor necrosis factor apoptosis 总被引:1,自引:0,他引:1
To determine if tumor necrosis factor (TNF)-mediated apoptosis affects cells at defined stages of the cell cycle, WEHI-164/2F (WEHI) cells were synchronized at G0-G1 after 3-day cultures in medium containing RPMI 1640 and 0.5% FCS (RPMI-0.5% FCS). The arrested WEHI cells (60-75% in G0-G1) showed increased sensitivity to TNF killing, measured as 48-h 3-(5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide assays, and 15-h apoptosis by propidium iodide staining and flow cytometry analysis. The TNF killing kinetics of G0-G1-arrested cells was similar to controls, and TNF did not accelerate or retard cell cycle progression of the arrested cells after feeding with fresh RPMI-0.5% FCS. However, TNF inhibited WEHI DNA synthesis as early as 1 h after treatment, and inhibition was proportionate to sensitivity to TNF-induced apoptosis. WEHI cells treated with TNF showed a higher percentage of cells in S phase with concomitant decrease in G0-G1 and G2-M. When cultured for 3-18 h in fresh RPMI-0.5% FCS to allow progression of the G0-G1-arrested cells toward the G1-S boundary, WEHI cells became more sensitive to TNF killing, especially at the 3-9 h time points. Moreover, TNF did not degrade [125I]5-iodo-2'-deoxyuridine-labeled WEHI DNA if the labeled cells were precultured for 9 h in fresh RPMI-0.5% FCS to allow them to pass S phase before the addition of TNF. These results show that TNF-induced apoptosis of WEHI cells is connected to cell cycle events; WEHI targets receive the TNF cytotoxic signal mainly at the G1-S boundary and begin to die by apoptosis as they exit from S phase. 相似文献
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Arthur W. Westerberg 《Computers & Chemical Engineering》1985,9(5):421-429
The last dozen years have produced almost 50 English language articles on the synthesis of separation systems [1]. Most work has considered separating a single relatively ideal mixture into sharply split, usually pure-component products using systems of single-feed, two-product distillation columns. Of late, the work has considered heat-integrating these columns to reduce energy consumption. Present research will very likely produce valuable results for nonsharp separations.Earlier approaches developed both algorithmic- and heuristic-based tree search algorithms for discovering the better systems of non-heat-integrated columns. New results permit the design of heat-integrated systems.The paper highlights the above developments. 相似文献
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The article proposes a theoretical framework in which moral reasoning about mediated crime and punishment is defined and combined with existing, affect-driven entertainment theory to yield an integrated theory of enjoyment. The authors analyze how crime dramas serve as statements about justice and then address how moral deliberation about the propriety of those statements impacts enjoyment. The authors report research findings to support the analysis of cognitive processing during crime dramas distinct from affective processing. The article also suggests future means by which the integrated theory of enjoyment can be examined. 相似文献
9.
Norris Fran H.; Murphy Arthur D.; Baker Charlene K.; Perilla Julia L.; Rodriguez Francisco Gutiérrez; Rodriguez José de Jesús Gutiérrez 《Canadian Metallurgical Quarterly》2003,112(4):646
Prevalence rates of trauma and posttraumatic stress disorder (PTSD) were estimated from a probability sample of 2,509 adults from 4 cities in Mexico. PTSD was assessed according to Diagnostic and Statistical Manual of Mental Disorders (American Psychiatric Association, 1994) criteria using the Composite International Diagnostic Interview (CIDI; WHO, 1997). Lifetime prevalence of exposure and PTSD were 76% and 11.2%, respectively. Risk for PTSD was highest in Oaxaca (the poorest city), persons of lower socioeconomic status, and women. Conditional risk for PTSD was highest following sexual violence, but nonsexual violence and traumatic bereavement had greater overall impact because of their frequency. Of lifetime cases, 62% became chronic; only 42% received medical or professional care. The research demonstrates the importance of expanding the epidemiologic research base on trauma to include developing countries around the world. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
10.
A. Vahid Shahidi I. Shih T. Araki C. H. Champness 《Journal of Electronic Materials》1985,14(3):297-310
Structural investigation on monocrystalline CuInSe2 samples has been made. From the single crystal results, the space group of CuInSe2 was confirmed to be Iˉ42d and the crystal solidification direction was investigated. Compositional uniformity of the ingots
was established by EPMA and it was found that the indium concentration was greater than that for copper. Systematic annealing
experiments were carried out in vacuum at different temperatures (as low as 160° C) and for different times. Large variation
in resistivity was observed after the annealing treatment. P-type samples were found to convert to n-type after the heat-treatments. 相似文献