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91.
James L. Gardner 《Color research and application》2014,39(5):430-435
Deconvolution based on the Richardson‐Lucy algorithm, recently suggested to be an effective method of reducing instrumental broadening effects in radiometric spectra, is applied to two examples relevant to colorimetry. The first is chromaticity measurement of light‐emitting diodes, where results are compared with more traditional weighted‐mean bandwidth correction. The second is accurate calibration of the wavelength scale of a medium‐resolution array spectrometer. Deconvolution is shown to be an effective tool in both cases. © 2013 Wiley Periodicals, Inc. Col Res Appl, 39, 430–435, 2014 相似文献
92.
S.J. Westerman E.J. Sutherland P.H. Gardner N. Baig C. Critchley C. Hickey S. Mehigan A. Solway Z. Zervos 《Food quality and preference》2013,27(1):8-17
On-package graphics have the potential to influence consumers’ product-related attitudes and behaviours. In the reported study graphics designs on the labels of two products (water and vodka) were manipulated with respect to shape angularity, orientation, and left–right alignment. Participants’ evaluations indicated a preference for rounded shapes that could not be accounted for by differences in design typicality; and preference for upward shape orientation. An interaction between these response variables for ratings of purchase likelihood suggested that congruence between graphical and product form (droplet shape) may be advantageous. Effects of alignment were not consistent with existing theories, with right-aligned graphics being preferred. An explanation that distinguishes processing efficiency and hemispheric efficiency is proposed. Finally, as predicted, a halo effect was apparent, such that effects of aesthetic manipulations extended to ratings of product attributes that were not experienced. Theoretical and practical implications of these results are discussed. 相似文献
93.
Vaid Jyotsna; Paivio Allan; Gardner Robert C.; Genesee Fred 《Canadian Metallurgical Quarterly》2010,65(4):290
On August 23, 2009, psychology lost an innovative researcher with the passing, at 86, of Wallace E. Lambert. A professor of psychology at McGill University from 1954 until 1990, Wallace (“Wally”) Lambert was among the founders of psycholinguistics and sociolinguistics. His highly productive career included contributions to social and cross-cultural psychology (intergroup attitudes, child-rearing values, and psychological consequences of living in multicultural societies), language education (the French immersion program), and bilingualism (measurement of language dominance, attitudes and motivation in second-language learning, and social, cognitive, and neuropsychological consequences of bilingualism). Indeed, because of the scope and influence of his work, Wally Lambert is widely considered the father of the psychological study of bilingualism. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
94.
Armstrong DG Gong JG Gardner JO Baxter G Hogg CO Webb R 《Reproduction (Cambridge, England)》2002,123(3):371-378
The nutritional status of a cow is a key factor in the regulation of both follicle growth and oocyte quality. In this study, the effect of diets designed to increase circulating insulin and insulin-like growth factor I (IGF-I) concentrations on steroid production by granulosa cells in vitro was examined to analyse the mechanisms through which these changes occur. Hereford x Friesian heifers (n = 24) were offered maintenance or twice maintenance diets during the experimental period (17 days). Circulating concentrations of FSH did not differ between the two dietary groups, whereas insulin and IGF-I concentrations showed significant diet x day of oestrous cycle interactions. Ovaries were collected on day 3 of the first follicle wave after synchronization of oestrus. Granulosa cells were isolated from small (1-4 mm) and medium-sized (4-8 mm) follicles and cultured in the presence of long R3-IGF-I or bFSH or both. After 4 days in culture, granulosa cells isolated from small follicles, but not medium-sized follicles, collected from cattle offered the twice maintenance diet secreted significantly higher (P < 0.05) amounts of oestradiol compared with granulosa cells collected from cattle offered the maintenance diet. The effect was apparent in either the presence or absence of FSH and long R3-IGF-I. This nutritional effect on aromatase activity in granulosa cells was not apparent after day 6 of culture. There was no effect of diet on progesterone production by granulosa cells after 4 or 6 days of culture. These results support the hypothesis that dietary-induced changes in circulating insulin and IGF-I concentrations have a direct effect on the steroidogenic potential of bovine granulosa cells from small follicles. The dietary-induced increases in aromatase activity in small follicles combined with the increased concentration of metabolic hormones are possible mechanisms through which short-term changes in nutrition may affect follicle dynamics. 相似文献
95.
Reducing a neural network's complexity improves the ability of the network to generalize future examples. Like an overfitted regression function, neural networks may miss their target because of the excessive degrees of freedom stored up in unnecessary parameters. Over the past decade, the subject of pruning networks produced nonstatistical algorithms like Skeletonization, Optimal Brain Damage, and Optimal Brain Surgeon as methods to remove connections with the least salience. The method proposed here uses the bootstrap algorithm to estimate the distribution of the model parameter saliences. Statistical multiple comparison procedures are then used to make pruning decisions. We show this method compares well with Optimal Brain Surgeon in terms of ability to prune and the resulting network performance. 相似文献
96.
Richard Van Nee V. K. Jones Geert Awater Allert Van Zelst James Gardner Greg Steele 《Wireless Personal Communications》2006,37(3-4):445-453
An overview is given of the new IEEE 802.11n standard. This is the first wireless LAN standard based on MIMO-OFDM, a technique pioneered by Airgo Networks to give a significant performance increase in both range and rate relative to conventional wireless LAN. Performance results show that net user throughputs over 100 Mbps are achievable, which is about four times larger than the maximum achievable throughput using IEEE 802.11a/g. For the same throughput, MIMO-OFDM achieves a range that is about 3 times larger than non-MIMO systems. This significant improvement in range-rate performance makes MIMO-OFDM the ideal solution not only for wireless LAN, but also for home entertainment networks and 4G networks.
Richard van Nee received the M.Sc. degree in Electrical Engineering from Twente University in Enschede, the Netherlands, in 1990. In May 1995, he received the PhD degree from Delft University of Technology. From 1995 to 2000, he worked for Lucent Technologies Bell Labs on wireless LAN transmission techniques. He was one of the original proposers of the CCK and OFDM modulation techniques which were adopted by the IEEE 802.11b and IEEE802.11a wireless LAN standards. In 2001, he cofounded Airgo Networks that developed the first MIMO-OFDM modem for wireless LAN and which techniques form the basis of the IEEE 802.11n standard. Together with Ramjee Prasad, he wrote a book on OFDM, entitled ‘OFDM for Mobile Multimedia Communications.’ In 2002 he received the Dutch Veder award for his contributions to standardization of wireless communications. 相似文献
97.
The Internet Chess Club (ICC) is a popular online chess server that started its existence in the early 1990s as the Internet chess server. Although the ICC Web site assures its users that the security protocol employed between the client and the server protects sensitive information, the authors show that this isn't true. This article examines two security aspects of the ICC. In moving from a free service to a commercial one, ICC's administrators introduced several enhancements to the original system, including time-stamping, a network security protocol, and online payments. 相似文献
98.
The current trend in constructing high-performance computing systems is to connect a large number of machines via a fast interconnect or a large-scale network such as the Internet. This approach relies on the performance of the interconnect (or Internet) to enable fast, large-scale distributed computing. A detailed understanding of the communication traffic is required in order to optimize the operation of the entire system. Network researchers traditionally monitor traffic in the network to gain the insight necessary to optimize network operations. Recent work suggests additional insight can be obtained by also monitoring traffic at the application level. The Monitor for Application-Generated Network Traffic toolkit (MAGNeT) we describe here monitors application traffic patterns in production systems, thus enabling more highly optimized networks and interconnects for the next generation of high-performance computing systems. 相似文献
99.
Liquid chromatographic (LC) separations for pesticides and many other compounds make use of nonvolatile buffers in the mobile phase. The coupling of LC with mass spectrometry (MS) does not allow the use of nonvolatile buffers. Substitution with volatile buffers is possible, but changes in chromatographic retention and resolution can result even if pH is held constant. The postcolumn removal of nonvolatile buffers using a commercially available ion suppressor is evaluated for the analysis of carbamate pesticides. The suppressor efficiently removes phosphate anions from an LC mobile phase. Most compounds show an increased signal by factors of 2-7 after postcolumn phosphate removal. The suppressor has little effect on the chromatographic parameters of some compounds, while serious negative effects are noted for others. Some compounds will give poor results due to adsorption or retention by the suppressor. The results indicate that such a device may be useful for the LC-MS analysis of some pesticides using nonvolatile buffers. 相似文献
100.
Disruption of seven hypothetical aryl alcohol dehydrogenase genes from Saccharomyces cerevisiae and construction of a multiple knock-out strain 总被引:1,自引:0,他引:1
By in silicio analysis, we have discovered that there are seven open reading frames (ORFs) in Saccharomyces cerevisiae whose protein products show a high degree of amino acid sequence similarity to the aryl alcohol dehydrogenase (AAD) of the lignin-degrading fungus Phanerochaete chrysosporium. Yeast cultures grown to stationary phase display a significant aryl alcohol dehydrogenase activity by degrading aromatic aldehydes to the corresponding alcohols. To study the biochemical and the biological role of each of the AAD genes, a series of mutant strains carrying deletion of one or more of the AAD-coding sequences was constructed by PCR-mediated gene replacement, using the readily selectable marker kanMX. The correct targeting of the PCR-generated disruption cassette into the genomic locus was verified by analytical PCR and by pulse-field gel electrophoresis (PFGE) followed by Southern blot analysis. Double, triple and quadruple mutant strains were obtained by classical genetic methods, while the construction of the quintuple, sextuple and septuple mutants was achieved by using the marker URA3 from Kluyveromyces lactis, HIS3 from Schizosaccharomyces pombe and TRP1 from S. cerevisiae. None of the knock-out strains revealed any mutant phenotype when tested for the degradation of aromatic aldehydes using both spectrophotometry and high performance liquid chromatography (HPLC). Specific tests for changes in the ergosterol and phospholipids profiles did not reveal any mutant phenotype and mating and sporulation efficiencies were not affected in the septuple deletant. Compared to the wild-type strain, the septuple deletant showed an increased resistance to the anisaldehyde, but there is a possibility that the nutritional markers used for gene replacement are causing this effect. 相似文献