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61.
62.
Amy Neustein 《International Journal of Speech Technology》2006,9(3-4):109-120
This paper will demonstrate how Sequence Package Analysis, as a new natural language understanding method that is built on a set of parsing structures that consist of context-free grammatical units and related prosodic features for identifying affective/emotional data found in natural speech and blogs, may better accommodate the goals of crisis management and rapid decision making in critical systems. Following an in depth discussion of the genesis and development of this method for the design of voice-user interfaces and audio mining programs, debuted in an earlier issue of IJST, this paper will attempt to show how Sequence Package Analysis can improve human response in monitoring recorded conversations of terror suspects and the recordings of help-line desks. In both instances, effective human intervention may help avert a crisis and resulting liability. The paper’s limited focus on these two respective domains does not, however, limit the applicability of Sequence Package Analysis to other critical systems, inasmuch as the parsing structures explained below are generic enough to be applied to other critical systems, such as ambulance control, aircraft or nuclear power stations, or 911 calls for help. Given that critical systems require effective human response from decision makers, natural language data must be accorded the same kind of scientific scrutiny given to graphic design and other features of human-computer interaction. 相似文献
63.
Gary Krug 《The Journal of communication》1995,45(2):204-209
64.
Background, prime influences upon present day methods and current trends in United Kingdom tendering practices are reviewed. Significant weaknesses are identified, confirming the need for some revision of existing contractor selection methods. The findings compliment recommendations of the recent government/industry review of the construction sector headed by Sir Michael Latham. Specifically, that tendering procedure should embrace investigation of contractors' potential to deliver a service of acceptable standard, on time, within budget. Present selection methods often fail in this objective, being inclined to discriminate predominantly on cost. 相似文献
65.
Methylation is one of the many post-translational modifications that modulate protein function. Although asymmetric NG,NG-dimethylation of arginine residues in glycine-arginine-rich domains of eucaryotic proteins, catalyzed by type I protein arginine N-methyltransferases (PRMT), has been known for some time, members of this enzyme class have only recently been cloned. The first example of this type of enzyme, designated PRMT1, cloned because of its ability to interact with the mammalian TIS21 immediate-early protein, was then shown to have protein arginine methyltransferase activity. We have now isolated rat and human cDNA orthologues that encode proteins with substantial sequence similarity to PRMT1. A recombinant glutathione S-transferase (GST) fusion product of this new rat protein, named PRMT3, asymmetrically dimethylates arginine residues present both in the designed substrate GST-GAR and in substrate proteins present in hypomethylated extracts of a yeast rmt1 mutant that lacks type I arginine methyltransferase activity; PRMT3 is thus a functional type I protein arginine N-methyltransferase. However, rat PRMT1 and PRMT3 glutathione S-transferase fusion proteins have distinct enzyme specificities for substrates present in both hypomethylated rmt1 yeast extract and hypomethylated RAT1 embryo cell extract. TIS21 protein modulates the enzymatic activity of recombinant GST-PRMT1 fusion protein but not the activity of GST-PRMT3. Western blot analysis of gel filtration fractions suggests that PRMT3 is present as a monomer in RAT1 cell extracts. In contrast, PRMT1 is present in an oligomeric complex. Immunofluorescence analysis localized PRMT1 predominantly to the nucleus of RAT1 cells. In contrast, PRMT3 is predominantly cytoplasmic. 相似文献
66.
Gary Gibson Xia Sheng Dick Henze Si‐Ty Lam Patricia Beck Yoocharn Jeon Zhang‐Lin Zhou Brad Benson Qin Liu Gregg Combs Tim Koch Kent Biggs 《Journal of the Society for Information Display》2012,20(10):552-558
Reflective displays are advantageous in applications requiring low power or daylight readability. However, there are no low‐cost reflective technologies capable of displaying bright colors. By employing photoluminescence to more efficiently use ambient light, we created a prototype display that provides bright, full color in a simple, low‐cost architecture. This prototype includes a novel electrokinetic shutter, a layer that incorporates patterned luminescent red, green, and blue sub‐pixel elements, and a novel optical out‐coupling scheme. The luminescent elements convert otherwise‐wasted portions of the incident spectrum to light in the desired color band, resulting in improved color saturation and lightness. This prototype provides a color gamut that is superior to competing reflective display technologies that utilize color filters in single‐layer side‐by‐side sub‐pixel architectures. The current prototype is capable of switching in <0.5 s; future displays based on an alternative electro‐optic shutter technology should achieve video rate operation. A transflective version of this technology has also been prototyped. The transflective version utilizes its backlight with a power efficiency that is at least three times that of a conventional liquid crystal display. These photoluminescence‐based technologies enable a host of applications ranging from low‐power mobile products and retail pricing signage to daylight readable signage for outdoor advertising segments. 相似文献
67.
We use molecular dynamics simulations in order to investigate the time evolution of the effect of adsorbed polymer coatings on the electro-osmotic flow (EOF) in a capillary. Weakly adsorbed coatings show no time-dependent performance, but they do not strongly reduce the EOF. On the other hand, strongly adsorbed coatings made of longer polymer chains are often quenched in non-equilibrium conformations that can strongly reduce the EOF over extremely long periods of time. For intermediate adsorption strengths, we observe that the EOF increases as a function of time due to the relaxation of the coating layer. The concentration of polymers in solution and the length of the polymer chains also affect the time-dependence of the EOF. These results show that the quality of electrophoretic separations can depend on the waiting time between the formation of the coating and the beginning of the separation. We conclude by suggesting experimental tests of our predictions. 相似文献
68.
Gary A. Williams 《Journal of Low Temperature Physics》1992,89(1-2):91-100
A vortex-ring formulation of the4He -transition provides a clear physical picture of the superfluid transition. The thermally excited rings are dipoles which orient in an applied flow field, and their net backflow cancels part of the applied flow, reducing the superfluid density. At the -point rings of infinite size drive the superfluid density to zero as a power law of the reduced temperature, with an exponent of 0.672. By fitting to the experimental superfluid amplitude the core energy of the smallest rings is found to be 6.1K at T and their diameter is 2.3 Å. It is proposed that these can be identified as the roton excitations of the Landau model. The vortex theory also yields new insights into topics such as boundary effects at a wall, finite-size effects, and the dynamics of the transition. 相似文献
69.
Joseph R. Fox P. Costa Kokoropoulos Gary H. Wiseman H. K. Bowen 《Journal of Materials Science》1987,22(12):4528-4531
Organosilanes of the general formula R
x
Si(OR)4–x
(where R is an alkyl group and R = CH3 or CH2CH3) were used to sterically stabilize hexane dispersions of submicrometre silica spheres. The dispersions were characterized according to sediment volume results. For 0.5m silica particles, the sediment density increased by more than a factor of three up to 50 to 55% of theoretical in the presence of organosilanes with 12 or more carbons in the R group. Solid-state13C nuclear magnetic resonance was used to characterize the powder-dispersant interaction; this technique can distinguish between carbons in the R group of the organosilane and residual organic groups in the silica. Scanning electron micrographs of filter compacts were used to further characterize the dispersions and indicated the presence of primary particles as well as small agglomerates. 相似文献
70.
Robin Wijngaard Meritxell Perramn Marina Parra-Robert Susana Hidalgo Gina Butrico Manuel Morales-Ruiz Muling Zeng Eudald Casals Wladimiro Jimnez Guillermo Fernndez-Varo Gerald I. Shulman Gary W. Cline Gregori Casals 《International journal of molecular sciences》2021,22(9)
The metabolic ratios lactate/pyruvate and β-hydroxybutyrate/acetoacetate are considered valuable tools to evaluate the in vivo redox cellular state by estimating the free NAD+/NADH in cytoplasm and mitochondria, respectively. The aim of the current study was to validate a gas-chromatography mass spectrometry method for simultaneous determination of the four metabolites in plasma and liver tissue. The procedure included an o-phenylenediamine microwave-assisted derivatization, followed by liquid-liquid extraction with ethyl acetate and silylation with bis(trimethylsilyl)trifluoroacetamide:trimethylchlorosilane 99:1. The calibration curves presented acceptable linearity, with a limit of quantification of 0.001 mM for pyruvate, β-hydroxybutyrate and acetoacetate and of 0.01 mM for lactate. The intra-day and inter-day accuracy and precision were within the European Medicines Agency’s Guideline specifications. No significant differences were observed in the slope coefficient of three-point standard metabolite-spiked curves in plasma or liver and water, and acceptable recoveries were obtained in the metabolite-spiked samples. Applicability of the method was tested in precision-cut liver rat slices and also in HepG2 cells incubated under different experimental conditions challenging the redox state. In conclusion, the validated method presented good sensitivity, specificity and reproducibility in the quantification of lactate/pyruvate and β-hydroxybutyrate/acetate metabolites and may be useful in the evaluation of in vivo redox states. 相似文献