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171.
The human equilibrative nucleoside transporter 1 protein (hENT1) is a major mediator of cellular entry of nucleosides and anticancer nucleoside drugs; its assay is important in understanding and diagnosing chemotherapy resistance. Here we present a novel assay for quantifying hENT1 using capillary electrophoresis with laser-induced fluorescence detection (CE-LIF). A cellular population is treated with 5'-S-(2-aminoethyl)-N6-(4-nitrobenzyl)-5'-thioadenosine-x8-fluorescein (5-SAENTA-x8f), which binds with high affinity and specificity to the hENT1 protein. The cells are washed to remove excess reagent, lysed, and centrifuged, and the supernatant is analyzed by CE-LIF with the use of an internal standard. Accuracy was evaluated by comparing the capillary electrophoresis results with those obtained by flow cytometry; the results were highly correlated, r = 0.96. The relative standard deviation of the hENT1 assay was 10%, determined from nine independent assays of the same cell line, which is 3 times superior to results obtained in a flow cytometry assay. The detection limit for 5-SAENTA-x8f was 4300 molecules injected into the capillary. 相似文献
172.
E. J. Cameron C. A. Norman Lillian Ruston Hassan Srinidhi 《Journal of Systems Integration》1992,2(4):389-404
Increasing diversity and sophistication among telecommunications customers has led to pressure on the telecommunications industry
to give customer groups the capability to customize aspects of offered telecommunications services for their own particular
needs. To offer such user-customizable services correctly, quickly, and cheaply, the telecommunications industry needs adequate
techniques for transforming user requirements into software specifications and for realizing these software specifications
with application code. In today's environment, several well-known software development life cycle processes exist for realizing
software specifications; however, analogous techniques for transforming user requirements into explicit software specifications
do not.
This paper proposes a technique for transforming user requirements and then demonstrates its use on a sample telecommunications
application. The technique creates a simulation environment that lets simulation users describe their application requirements
and then determine the appropriate software specifications needed. The technique builds on aspects of a service-driven specification
model and simulation software tools published earlier. Because the simulation environment derives from user requirements and
produces software specifications, the proposed technique could represent the first phase of a service-driven software development
life cycle process, eventually evolving from the nonservice-driven “requirements analysis” phase commonly used in practice
today. 相似文献
173.
Lillian Schwartz 《The Visual computer》1993,9(4):213-226
Surprising new insights into Piero della Francesca's revered painting,The Resurrection of Christ, have emerged from a computer-aided analysis of the structure and color Piero employed in his art: Christ's features seem to be asymmetrical; a tree made of thorns has been identified; and upon filtering with red, as the dominant color, the fresco appears as if it were bathed in the color and light of a setting sun. In addition, electronic reconstructions of his frescoes,La morte di Adamo andSt. Julien, demonstrate a new use for the computer as a valuable aid to the art restorer and provide the world with a view of the works as they appeared upon completion over 500 years ago. Finally, an examination of Piero's composition, together with a comparison between the fresco medium and the computer medium, extends previously recognized links to modern art and to computer art in particular. 相似文献
174.
Lillian D. Wakeley Alan Davis Robert G. Jenkins Gareth D. Mitchell Philip L. Walker 《Fuel》1979,58(5):379-385
Solids accumulated in the reactor of a solvent-refined coal (SRC-1) pilot plant during processing of three coals were studied using optical microscopy and X-ray diffraction. A classification system was devised for each of the two groups of components: organic materials and mineral matter. The various organic components were classified by the extent of change from the original coal macerals, and by optical properties of different semi-cokes and other organic phases. Minerals were divided into four groups: those unchanged from the original coal; minerals which were physically degraded; minerals which were chemically or crystallographically transformed; and those minerals formed during processing of a subbituminous coal. Gold-tube carbonization experiments were performed on SRC to determine the conditions under which retrogressive reactions occur to form mesophase semi-coke. Autoclave experiments were designed to investigate the recrystallization of pyrite as pyrrhotites, and to determine the causes of carbonate-mineral formation in the reactor. Calcium carbonate was found to crystallize from the interaction of ion-exchangeable calcium and carbon dioxide, which are available when low-rank coals are processed. 相似文献
175.
Similarity-Based Models of Word Cooccurrence Probabilities 总被引:15,自引:0,他引:15
In many applications of natural language processing (NLP) it is necessary to determine the likelihood of a given word combination. For example, a speech recognizer may need to determine which of the two word combinations eat a peach and eat a beach is more likely. Statistical NLP methods determine the likelihood of a word combination from its frequency in a training corpus. However, the nature of language is such that many word combinations are infrequent and do not occur in any given corpus. In this work we propose a method for estimating the probability of such previously unseen word combinations using available information on most similar words.We describe probabilistic word association models based on distributional word similarity, and apply them to two tasks, language modeling and pseudo-word disambiguation. In the language modeling task, a similarity-based model is used to improve probability estimates for unseen bigrams in a back-off language model. The similarity-based method yields a 20% perplexity improvement in the prediction of unseen bigrams and statistically significant reductions in speech-recognition error.We also compare four similarity-based estimation methods against back-off and maximum-likelihood estimation methods on a pseudo-word sense disambiguation task in which we controlled for both unigram and bigram frequency to avoid giving too much weight to easy-to-disambiguate high-frequency configurations. The similarity-based methods perform up to 40% better on this particular task. 相似文献
176.
Bioluminescence ATP monitoring as a surrogate marker for microbial load on hands and surfaces in the home 总被引:2,自引:0,他引:2
Larson EL Aiello AE Gomez-Duarte C Lin SX Lee L Della-Latta P Lindhardt C 《Food microbiology》2003,20(6):735-739
To evaluate the validity and reliability of adenosine triphosphate (ATP) monitoring as a surrogate marker for cleanliness, the kitchen table surface in 225 inner-city homes was sampled by microbiologic culture and by two types of biomass monitoring systems (HY-LiTEtrade mark 2 ATP System and HY-RiSE Colour Hygiene Test Strip, EM Science, Gibbstown, New Jersey, USA). A randomly selected hand of the homemaker (n = 225) was also cultured and sampled with the ATP monitoring system immediately after handwashing. Log microbial counts on hands ranged from 3.2 to 7.0 and from the table, 1.0 to 5.5. While the traditional ATP readings (HY-LiTE) and the color strips were significantly correlated (R = 0.18, P = 0.01), there was no significant correlation between the ATP monitor readings and the colony-forming units counts on either the hands (R = 0.03, P = 0.62) or the table (R = 0.04, P = 0.58). Such biomass measurements are not a substitute for quantitation of microbial load. 相似文献
177.
Wild greens are nutritionally well-balanced vegetables. Herein, nutritional and in vitro antioxidant properties of the sprouts of three commonly used species were determined. Wild asparagus revealed the highest levels of moisture (84.6 g/100 g fw), ash (12.3 g/100 g dw), proteins (22.4 g/100 g dw), total sugars (9.24 g/100 g dw), including sucrose (4.27 g/100 g dw), and of the essential n-6 fatty acid linoleic acid (44.5%); white bryony gave the highest contents of reducing sugars, including glucose (2.97 g/100 g dw), essential n-3 fatty acid α-linolenic acid (70.3%), and the best ratios of PUFA/SFA, and n-6/n-3 fatty acids (3.59 and 0.0907, respectively); black bryony showed the highest concentrations of carbohydrates (69.3 g/100 g dw), fructose and trehalose (3.83 and 1.34 g/100 g dw, respectively). Besides their culinary characteristics, their high content in vitamins (asparagus, 135 and 142 mg/100 g dw of total tocopherols and ascorbic acid, respectively), chlorophylls (white bryony, 50.9 mg/100 g dw), carotenoids (23.3 mg/100 g dw) and phenolics (black bryony, 759 mg GAE/g extract), together with the antioxidant properties (EC50 values lower than 640 μg/ml) and potential health benefits increase their importance in traditional as well as in contemporary diets. 相似文献
178.
Sushil Anand Sandip Kamath Lillian Chuang Stefan Kasapis Andreas L. Lopata 《European Food Research and Technology》2013,236(5):873-882
Australasia has a large fish industry, and fish skin by-products from the processing industry could be used for the commercial production of fish collagen. The aim of this study was to characterize collagen extracted from the Asian sea bass (Australian barramundi) (Lates calcarifer) and snapper (Pagrus auratus) skin as an alternative to mammalian-derived collagen in gelatin products. The acid-soluble fractions of collagen from Asian sea bass and snapper skin were extracted and yielded about 8 and 7.5 % collagen (on a dry weight basis), respectively. The electrophoretic and chromatography patterns indicated that both collagens comprise of α1, α2, α3, and β chains, corresponding to the properties of calf skin collagen type I. Amino acid analysis and peptide mapping of digested collagen suggested differences in their amino acid sequences and collagen primary structure. Fourier transform infrared spectroscopy demonstrated that the helical structure of collagen was completely maintained in Asian sea bass and partially in snapper. Transition temperatures for the completion of the melting process in the two collagen networks were confirmed with differential scanning calorimetry and dynamic oscillatory rheology to be about 29 °C. Zeta potential analysis identified the isoelectric points (pI values) of collagen from Asian sea bass and snapper skin at pH 6.90 and 7.75, respectively. Thus, Asian sea bass and snapper skin could be an important alternative source of collagen to replace mammalian collagen for industrial applications. 相似文献