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911.
A robust finding in humans and animals is that intermixed exposure to 2 similar stimuli (AX/BX) results in better discriminability of those stimuli on test than does exposure to 2 equally similar stimuli in 2 separate blocks (CX_DX)--the intermixed-blocked effect. This intermixed-blocked effect may be an example of the superiority of spaced over massed practice; in the intermixed, but not the blocked exposure regime, each presentation of a given stimulus (e.g., AX) is separated from the next by the presentation of its partner (BX). Two experiments with human participants replicated the intermixed-blocked effect and showed that the effect was not due to the spacing of exposure trials. A mechanism for the intermixed-blocked effect is proposed, which combines theories from associative learning and memory. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
912.
Geoffrey I. Webb 《Machine Learning》2008,71(2-3):307-323
Standard pattern discovery techniques, such as association rules, suffer an extreme risk of finding very large numbers of spurious patterns for many knowledge discovery tasks. The direct-adjustment approach to controlling this risk applies a statistical test during the discovery process, using a critical value adjusted to take account of the size of the search space. However, a problem with the direct-adjustment strategy is that it may discard numerous true patterns. This paper investigates the assignment of different critical values to different areas of the search space as an approach to alleviating this problem, using a variant of a technique originally developed for other purposes. This approach is shown to be effective at increasing the number of discoveries while still maintaining strict control over the risk of false discoveries. 相似文献
913.
The aim of this study was to determine if differential solubilization of human CNS proteins would increase the total number of proteins that could be visualized using 2-D gel electrophoresis. Hence, proteins were solubilized into Tris, CHAPS and SB3-10 before separation across a pH 4-7 IEF gradient and a 12-14% SDS polyacrylamide gel, which could be achieved with a run-to-run variation of 35% in spot intensity. Because Western blot analyses suggested proteins could be in more than one detergent fraction, we completed a conservative analyses of our 2-D gels assuming spots that appeared on multiple gels at the same molecular weight and pI were the same protein. These analyses show that we had visualized over 3000 unique protein spots across three 2-D gels generated from each sample of human frontal cortex and caudate-putamen. This represented, at worst, a significant increase in the number of spots visualized in the acidic protein spectrum compared to what has been reported in other studies of human CNS. This study, therefore, supports the proposal that the analysis of the human CNS proteome using 2-D gel electrophoresis, combined with appropriate sample preparation, can be used to expand the studies on the pathologies of neurological and psychiatric diseases. 相似文献
914.
Abstract: This paper describes a new method for classifying three-dimensional environments in real time using Kohonen self-organizing maps (SOMs). The method has been developed to enable autonomous underwater vehicles (AUVs) to navigate without human intervention in previously unexplored subsea environments, but can be generalized to unmanned aircraft equipped with appropriate sensors flying over unchartered terrains, or spacecraft exploring remote planets, subject to appropriate pre-mission training. The method involves a fuzzy comparison between a SOM created in real time using accumulated sensor data and a class atlas of SOMs derived from previously trained and manually classified environments. This enables mission- and environment-appropriate AUV navigation strategies to be selected in real time. Simulation results using real-world, three-dimensional environment data acquired from digital elevation maps are presented, which demonstrate the potential of the method. 相似文献
915.
Gwyneth Rice Andrew R. Barber Andrea J. O’Connor Arto Pihlajamaki Marianne Nystrom Geoffrey W. Stevens Sandra E. Kentish 《Journal of food engineering》2011,107(2):164-172
The nanofiltration of dairy ultrafiltration permeate can be used to produce a concentrated lactose product that is reduced in unwanted monovalent salts. In this paper, the surface charge of three nanofiltration membranes commonly used for such a purpose is examined. The focus is the impact of multivalent anions, notably phosphate and citrate, upon the surface charge of the membranes within a ternary system of potassium and calcium chloride. It was shown that these multivalent anions can influence the membrane charge through interactions with calcium, even though they are unlikely to adsorb to the membrane surface. Specifically, both phosphate and citrate can form soluble charged species with the calcium ions, reducing the net Ca2+ concentration and hence the overall effect of calcium on the membrane. This ion interaction effect becomes more dominant at higher pH values, due to the greater tendency of calcium to interact with either phosphate or citrate at higher pH. 相似文献
916.
Mahnaz Kazemipoor Geoffrey A. Cordell Md. Moklesur Rahman Sarker Che wan Jasimah Bt Wan Mohamed Radzi Majid Hajifaraji Phua En Kiat 《International Journal of Food Properties》2013,16(9):1942-1963
Obesity is emerging globally as a leading, underlying contributor to a variety of different diseases, some of which are fatal. This study aims to provide a brief review of the botanical sources which are available to serve as an alternative to modern, synthetic anti-obesity drugs, and to provide a brief discussion of their mechanism of action, and their safe and effective usage. Information was gathered from books, journals, and a variety of electronic sources published in the period of 1991 to 2014. Medicinal plants can reduce weight through five basic mechanisms: controlling appetite, stimulating thermogenesis and lipid metabolism, inhibiting pancreatic lipase activity, preventing adipogenesis, and promoting lipolysis. Based on a review of the available literature, the consumption of recommended medicinal plants in a single form, and at an optimum dosage, could be a safe and effective complementary treatment for obesity. 相似文献
917.
Nilgün H. Budak Elif Aykin Atif C. Seydim Annel K. Greene Zeynep B. Guzel‐Seydim 《Journal of food science》2014,79(5):R757-R764
A variety of natural vinegar products are found in civilizations around the world. A review of research on these fermented products indicates numerous reports of health benefits derived by consumption of vinegar components. Therapeutic effects of vinegar arising from consuming the inherent bioactive components including acetic acid, gallic acid, catechin, ephicatechin, chlorogenic acid, caffeic acid, p‐coumaric acid, and ferulic acid cause antioxidative, antidiabetic, antimicrobial, antitumor, antiobesity, antihypertensive, and cholesterol‐lowering responses. The aims of this article are to discuss vinegar history, production, varieties, acetic acid bacteria, and functional properties of vinegars. 相似文献
918.
Tamanna Sultana Geoffrey P Savage David L McNeil Noel G Porter Richard J Martin Bas Deo 《Journal of the science of food and agriculture》2002,82(13):1477-1482
Wasabi (Wasabia japonica (Miq) Matsum) is a developing crop in New Zealand and is valued for its spicy taste and pungent smell. It is popular as a condiment for traditional and modern Japanese foods. However, the limited area suitable for wasabi production in Japan has resulted in inability to meet increasing market demand. Isothiocyanates (ITCs) are sulphur compounds responsible for the unique flavour of wasabi, with allyl isothiocyanate (AITC) being the main compound responsible for the pungency. In this study, AITC tissue concentration and yield were measured in three above‐ground tissues of the wasabi plant to investigate the effects of different fertiliser, manure and lime treatments. The highest tissue concentration of AITC was found in the rhizomes, ranging from 1564 to 3366 mg kg?1 (fresh weight basis), while the petioles and leaves contained 254–373 and 453–643 mg kg?1 respectively. Fertilisation with ammonium sulphate produced the highest‐quality rhizomes (72% increase in AITC yield) and petioles (64% increase), but the best response in the leaves (51%) resulted from the manure treatment. Nitrogen fertiliser alone reduced the AITC yield by up to 15%. These results should help in formulating guidelines for production of high‐quality wasabi tops containing high levels of AITC. © 2002 Society of Chemical Industry 相似文献
919.
Attia M. Elfak Geoffrey Pass Glyn O. Phillips 《Journal of the science of food and agriculture》1978,29(6):557-562
The apparent viscosities of dilute solutions of K-carrageenan and sodium carboxymethylcellulose have been measured and the intrinsic viscosities calculated. Added glucose, sucrose and glucose syrup increase the apparent viscosities of the solutions but give lower values for the intrinsic viscosity. In the presence of glucose syrup the macromolecules exhibit the behaviour associated with neutral macromolecules. This is attributed to the presence of inorganic cations in the glucose syrup which, by interaction with the polyanion, prevent dissociation of the ionic groups in the polysaccharides. 相似文献
920.
Nicola M Schreurs Michael H Tavendale Geoffrey A Lane Tom N Barry Nicolas López‐Villalobos Warren C McNabb 《Journal of the science of food and agriculture》2007,87(6):1076-1087
The objectives of this work were to establish the effect of seven different forages with a varied condensed tannin (CT) content, plant maturity and nitrogen fertiliser application on the ruminal formation of skatole and indole using an in vitro method designed to mimic rumen fermentation conditions. After 10 h of incubation, the concentration of indole and skatole was highest when incubating white clover (P < 0.05). Polyethylene glycol addition, to inhibit CT, showed that CT significantly reduced the formation of indole and skatole when incubating Lotus corniculatus, sulla, Dorynium rectum and Lotus pedunculatus (P < 0.01). Mature forage growth resulted in a significantly lower concentration of indole and skatole being formed in vitro compared to the incubation of new spring growth (P < 0.001). A higher application of nitrogen fertiliser to perennial ryegrass‐based pasture resulted in a higher crude protein concentration in the plant and a significantly higher concentration of skatole formed in vitro (P < 0.001). Forages containing CT reduced the conversion of endogenous protein to indole and skatole and plants containing a higher CT concentration tended to be more effective, but compositional differences of CT between forages may also have had an influence. New forage growth or swards that had a high application of nitrogen fertiliser promoted the formation of indole and skatole. Copyright © 2007 Society of Chemical Industry 相似文献