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11.
Ana Hulshof Lyn Pemberton Richard Griffiths 《Universal Access in the Information Society》2013,12(1):21-35
Preschool children have increased access to media via a number of platforms, including digital interactive television. However, the viewing and interaction needs of this user group have not been extensively researched. The project reported in this paper investigates preschoolers’ interactions with a simulated interactive television set-up. The study involved the development of an electronic programme guide prototype and its empirical evaluation. This research was carried out with children in Brazil and in the United Kingdom, aged between three and four. The main issues that arose during the interaction with the prototype application are documented, and a list of design principles is presented to assist in the design of accessible preschool interactive television applications for this age group. 相似文献
12.
Alistair Wood Yuval Gurfinkel Nicole Polain Wesley Lamont Sarah Lyn Rea 《International journal of molecular sciences》2021,22(9)
Amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD) are neurodegenerative disorders that exist on a disease spectrum due to pathological, clinical and genetic overlap. In up to 97% of ALS cases and ~50% of FTLD cases, the primary pathological protein observed in affected tissues is TDP-43, which is hyperphosphorylated, ubiquitinated and cleaved. The TDP-43 is observed in aggregates that are abnormally located in the cytoplasm. The pathogenicity of TDP-43 cytoplasmic aggregates may be linked with both a loss of nuclear function and a gain of toxic functions. The cellular processes involved in ALS and FTLD disease pathogenesis include changes to RNA splicing, abnormal stress granules, mitochondrial dysfunction, impairments to axonal transport and autophagy, abnormal neuromuscular junctions, endoplasmic reticulum stress and the subsequent induction of the unfolded protein response. Here, we review and discuss the evidence for alterations to these processes that have been reported in cellular and animal models of TDP-43 proteinopathy. 相似文献
13.
The ethyl eosin/ascorbic acid photosensitized polymerization of vinyl acetate in aqueous methanol using visible radiation has been shown to occur by a mechanism in which polymerization occurs after an induction period during which the dye colour fades completely. During this period the dye is excited by incident radiation and reacts with the reducing agent to form free radical species. These react with dissolved oxygen to produce hydrogen peroxide. It is shown that the polymerization of vinyl acetate is initiated by products of the reaction between ascorbic acid and hydrogen peroxide. 相似文献
14.
M.E. Lyn R.M. Zablotowicz B.J. Johnson 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2013,30(3):381-387
While soil application of a competitive non-toxigenic Aspergillus flavus strains is successful in reducing aflatoxin contamination in certain crops, direct application to aerial reproductive structures could be more effective for maize. A sprayable, clay-based water-dispersible granule formulation was developed to deliver non-toxigenic A. flavus strain K49 directly to maize ears. The efficacy of the K49 water-dispersible granule in mitigating aflatoxin in maize (Zea mays L.) was evaluated. Field studies were conducted to compare K49 colonization and effectiveness in reducing aflatoxin contamination when applied either as a soil inoculant or as a directed spray in plots infested with toxigenic strain F3W4. Fifty percent of non-toxigenic A. flavus was recovered from non-treated controls and from plots soil inoculated with K49 on wheat. In spray treatments with formulated or unformulated K49 conidia, over 90% of A. flavus recovered was non-toxigenic. Soil-applied K49 reduced aflatoxin contamination by 65% and spray applications reduced contamination by 97%. These findings suggest direct spray application of non-toxigenic A. flavus strains may be better than soil inoculation at controlling maize aflatoxin contamination and that a water-dispersible granule is a viable delivery system for maintaining viability and efficacy of the biological control agent, K49. 相似文献
15.
Two experiments examined solicitation of information in a group structured as a judge–advisor system (JAS) with 1 group member designated as the decision maker and the other 2 members as advisors. The decision maker solicited information from 2 advisors. One advisor's information was shared in common with the decision maker, and the other's information was predominantly unshared. In 2 experiments, decision makers asked for more information from the advisor with unshared information and rated this advisor's information as more important and influential than the advisor with only redundant, shared information. When decision makers were not limited in the amount of information they could ask for, decision makers significantly increased requests for information from the advisor with shared information but not the advisor with unshared information. Experiment 2 found that whether or not an advisor agreed with the decision maker did not affect decision makers' preference for the advisor with unshared information. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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The solution of the St. Venant–Exner equations as a model for bed evolution is studied under conditions when the Froude number, F, approaches unity, and the quasi-steady model becomes singular. It is confirmed that the strict criterion for critical flow, the vanishing of a water surface disturbance celerity, is not met, yet the direction of propagation of a bed wave apparently changes depending on whether F>1 or F<1. An analysis of the linearized model problem for an infinitesimal bed wave under near-uniform conditions is performed, and qualitative features of the solution are brought out. Under appropriate sediment transport conditions, when F2→1, two bed waves, one traveling upstream and the other traveling downstream, are found to develop from an initially single localized bed perturbation. Simulations of the full unsteady problem were performed with the Preissmann scheme to confirm the linear analysis and to study the effects of nonlinearity and friction. A transcritical case, in which a region where F2<1 is succeeded by a region where F2>1, is also investigated, and the solution exhibits an apparently different behavior than cases where the flow is everywhere sub- or supercritical, but can be understood as a hybrid of the latter cases. 相似文献
19.
Frank R. Safayeni R. Lyn Purdy Christopher A. Higgins 《Behaviour & Information Technology》1989,8(2):99-107
The social meaning of personal computers for 34 managers and professionals was measured using a situational approach. The results, in general, indicated a positive perception towards computers within the context of their work situations. The methodology was developed in an attempt to overcome some of the difficulties of traditional measures of attitudes. The advantages and the limitations of the method, as well as the process by which impressions are formed, are discussed. 相似文献
20.
Brébion Gildas; Ohlsen Ruth I.; Pilowsky Lyn S.; David Anthony S. 《Canadian Metallurgical Quarterly》2008,22(3):383
Objective: An association between hallucinations and reality-monitoring deficit has been repeatedly observed in patients with schizophrenia. Most data concern auditory/verbal hallucinations. The aim of this study was to investigate the association between visual hallucinations and a specific type of reality-monitoring deficit, namely confusion between imagined and perceived pictures. Method: Forty-one patients with schizophrenia and 43 healthy control participants completed a reality-monitoring task. Thirty-two items were presented either as written words or as pictures. After the presentation phase, participants had to recognize the target words and pictures among distractors, and then remember their mode of presentation. Results: All groups of participants recognized the pictures better than the words, except the patients with visual hallucinations, who presented the opposite pattern. The participants with visual hallucinations made more misattributions to pictures than did the others, and higher ratings of visual hallucinations were correlated with increased tendency to remember words as pictures. No association with auditory hallucinations was revealed. Conclusions: Our data suggest that visual hallucinations are associated with confusion between visual mental images and perception. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献