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1.
The changes to the chemical senses of taste and smell that accompany ageing are widely documented, and there has been some evidence that these changes may influence food preferences of the older consumer. However, little is known about the loss of function of the residual senses of texture and chemical irritant perception and how such losses influence food preferences. A consumer panel comprising a young (20–35 years) and an older (>65 years) age cohort was recruited and sensory tests were conducted to determine perceived intensity, preferences and the possibility of cross modal interaction between the sensory modalities of chemical irritation and texture. Liquid, semi-solid and solid food systems were studied to enable comparisons to be drawn. Older consumers were less capable of discriminating between chemical irritation and texture stimuli, indicating loss of sensory function, but there was indication that higher levels of chemical irritation were preferred among older consumers in some texture types.  相似文献   
2.
传统的高精密电容检测和阻抗检测应用需要将一套收集的分立器件巧妙的组合起来以提供完整的测量解决方案。这种方法不仅在器件选择方面十分耗时,并且由于各个应用之间即使有很小的差异,也需要做大量设计验证、评估、优化和鉴定。  相似文献   
3.
The dislocation structures of bulk textured and epitaxial thin film YBa2Cu3O7 superconductors are examined. Correlations between increases in flux pinning and dislocation densities are noted. A model for flux pinning by individual dislocations is presented. This gives a treatment of strain induced effects and effects of normal state region interactions. It is shown that the values of pinning predicted are in line with experimental observations.  相似文献   
4.
In this paper, we describe a pervasive game, Blowtooth, in which players use their mobile phones to hide virtual drugs on nearby airline passengers in real airport check-in queues. After passing through airport security, the player must find and recover their drugs from the innocent bystanders, without them ever realising they were involved in the game. The game explores the nature of pervasive game playing in environments that are not, generally, regarded as playful or “fun”. This paper describes the game’s design and implementation as well as an evaluation conducted with participants in real airports. It explores the players’ reactions to the game through questionnaire responses and in-game activity. The technologies used in Blowtooth are, intentionally, simple in order for the enjoyment of the game to be reliant more on the physical environment rather than the enabling technologies. We conclude that situating pervasive games in unexpected and challenging environments, such as international airports, may provide interesting and unique gaming experiences for players. In addition, we argue that pervasive games benefit most from using the specific features and nature of interesting real-world environments rather than focusing on the enabling technologies.  相似文献   
5.
Studies into the effects of stereotype threat (ST) on test performance have shed new light on race and sex differences in achievement and intelligence test scores. In this article, the authors relate ST theory to the psychometric concept of measurement invariance and show that ST effects may be viewed as a source of measurement bias. As such, ST effects are detectable by means of multigroup confirmatory factor analysis. This enables research into the generalizability of ST effects to real-life or high-stakes testing. The modeling approach is described in detail and applied to 3 experiments in which the amount of ST for minorities and women was manipulated. Results indicate that ST results in measurement bias of intelligence and mathematics tests. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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A ranking system for veterinary medicinal products and coccidiostat feed additives has been developed as a tool to be applied in a risk-based approach to the residue testing programme for foods of animal origin in the Irish National Residue Control Plan (NRCP). Three characteristics of substances that may occur as residues in food are included in the developed risk ranking system: Potency, as measured by the acceptable daily intake assigned by the European Medicines Agency Committee for Medicinal Products for Veterinary Use, to each substance; Usage, as measured by the three factors of Number of Doses, use on Individual animals or for Group treatment, and Withdrawal Period; and Residue Occurrence, as measured by the number of Non-Compliant Samples in the NRCP. For both Number of Doses and Non-Compliant Samples, data for the 5-year period 2008–12 have been used. The risk ranking system for substances was developed for beef cattle, sheep and goats, pigs, chickens and dairy cattle using a scoring system applied to the various parameters described above to give an overall score based on the following equation: Potency × Usage (Number of Doses + Individual/Group Use + Withdrawal Period) × Residue Occurrence. Applying this risk ranking system, the following substances are ranked very highly: antimicrobials such as amoxicillin (for all species except pigs), marbofloxacillin (for beef cattle), oxytetracycline (for all species except chickens), sulfadiazine with trimethoprim (for pigs and chickens) and tilmicosin (for chickens); antiparasitic drugs, such as the benzimidazoles triclabendazole (for beef and dairy cattle), fenbendazole/oxfendazole (for sheep/goats and dairy cattle) and albendazole (for dairy cattle), the avermectin ivermectin (for beef cattle), and anti-fluke drugs closantel and rafoxanide (for sheep/goats); the anticoccidials monensin, narasin, nicarbazin and toltrazuril (for chickens). The risk ranking system described is a relatively simple system designed to provide a reliable basis for selecting the veterinary medicinal products and coccidiostat feed additives that might be prioritised for residue testing.  相似文献   
8.
With growing demand for flexibility in manufacturing processes, interest in dexterous industrial robots is increasing. To facilitate benchmarking, and to assess the suitability of these robots for flexible manufacturing tasks, there is a need to develop new methods of capturing the relevant performance characteristics of industrial robots. This research aims to show that the Boothroyd-Dewhurst (B-D) Design-For-Assembly method, an established method for optimizing manufacturing processes, can be effectively adopted to form the basis of a comprehensive robotic dexterity assessment within flexible manufacturing. A comparative study is conducted which shows that the B-D classification tables offer the most comprehensive solution due to the range of operations and artifacts considered. Building on these tables, a framework is developed for determining the suitability of a robot system within flexible manufacturing operations. In a sample test-case scenario involving a pick-and-place operation, the framework is shown to produce an accurate estimate of robot performance that can be easily compared to human data. The framework establishes a link between manufacturing operations and robot performance metrics, which addresses the current difficulty in robot integration and highlights the framework’s potential for adoption within flexible manufacturing.  相似文献   
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10.
There are reports that nano-sized zero-valent iron (Fe0) exhibits greater reactivity than micro-sized particles of Fe0, and it has been suggested that the higher reactivity of nano-Fe0 may impart advantages for groundwater remediation or other environmental applications. However, most of these reports are preliminary in that they leave a hostof potentiallysignificant(and often challenging) material or process variables either uncontrolled or unresolved. In an effort to better understand the reactivity of nano-Fe0, we have used a variety of complementary techniques to characterize two widely studied nano-Fe0 preparations: one synthesized by reduction of goethite with heat and H2 (Fe(H2)) and the other by reductive precipitation with borohydride (Fe(BH)). Fe(H2) is a two-phase material consisting of 40 nm alpha-Fe0 (made up of crystals approximately the size of the particles) and Fe3O4 particles of similar size or larger containing reduced sulfur; whereas Fe(BH) is mostly 20-80 nm metallic Fe particles (aggregates of <1.5 nm grains) with an oxide shell/coating that is high in oxidized boron. The FeBH particles further aggregate into chains. Both materials exhibit corrosion potentials that are more negative than nano-sized Fe2O3, Fe3O4, micro-sized Fe0, or a solid Fe0 disk, which is consistent with their rapid reduction of oxygen, benzoquinone, and carbon tetrachloride. Benzoquinone-which presumably probes inner-sphere surface reactions-reacts more rapidly with FeBH than Fe(H2), whereas carbon tetrachloride reacts at similar rates with FeBH and Fe(H2), presumably by outer-sphere electron transfer. Both types of nano-Fe0 react more rapidlythan micro-sized Fe0 based on mass-normalized rate constants, but surface area-normalized rate constants do not show a significant nano-size effect. The distribution of products from reduction of carbon tetrachloride is more favorable with Fe(H2), which produces less chloroform than reaction with Fe(BH).  相似文献   
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