4,593 research outputs found
Beyond naming patterns in children with WFDs: definitions for nouns and verbs
Children who experience difficulties in naming are described as having word finding difficulties (WFDs). In the present study 31 children with WFDs were identified through a wider survey of educational provision for those with language and communication difficulties. The children were included if they were between 6;4-7;10 years, had normal non-verbal intelligence, no major articulation difficulties and had WFDs as diagnosed by standard scores below 75 on Test of Word Finding Difficulties (TWF, German, 1989). Three control groups were identified who were matched on: chronological age (N = 31), naming age (N = 31) and level of receptive grammar (N = 31). Children?s accuracy of naming and latency to name were assessed for pictures of objects and actions. Children were asked to define the object and action terms at a later point. Children with WFDs were significantly less accurate in naming than their age matched peers but equivalent to that of the language matched peers. The group of children with WFDs were the slowest to accurately name all sets of items. All groups of children were less accurate in the provision of definitions for action terms than object terms. Overall the children with WFDs provided fewer accurate definitions than their chronological age matched peers. The nature of the children?s definitions indicated that they also differed from their language-matched peers. Particular difficulties were noted in the provision of semantic categorisation information. A range of standardised language assessments did not account for these difficulties. The findings are discussed in relation to the idea that WFDs are caused by impoverished semantic representations
Establishing the behavioural limits for countershaded camouflage
Countershading is a ubiquitous patterning of animals whereby the side that typically faces the highest illumination is darker. When tuned to specific lighting conditions and body orientation with respect to the light field, countershading minimizes the gradient of light the body reflects by counterbalancing shadowing due to illumination, and has therefore classically been thought of as an adaptation for visual camouflage. However, whether and how crypsis degrades when body orientation with respect to the light field is non-optimal has never been studied. We tested the behavioural limits on body orientation for countershading to deliver effective visual camouflage. We asked human participants to detect a countershaded target in a simulated three-dimensional environment. The target was optimally coloured for crypsis in a reference orientation and was displayed at different orientations. Search performance dramatically improved for deviations beyond 15 degrees. Detection time was significantly shorter and accuracy significantly higher than when the target orientation matched the countershading pattern. This work demonstrates the importance of maintaining body orientation appropriate for the displayed camouflage pattern, suggesting a possible selective pressure for animals to orient themselves appropriately to enhance crypsis
Is countershading camouflage robust to lighting change due to weather?
Countershading is a pattern of coloration thought to have evolved in order to implement camouflage. By adopting a pattern of coloration that makes the surface facing towards the sun darker and the surface facing away from the sun lighter, the overall amount of light reflected off an animal can be made more uniformly bright. Countershading could hence contribute to visual camouflage by increasing background matching or reducing cues to shape. However, the usefulness of countershading is constrained by a particular pattern delivering ‘optimal’ camouflage only for very specific lighting conditions. In this study, we test the robustness of countershading camouflage to lighting change due to weather, using human participants as a ‘generic’ predator. In a simulated three-dimensional environment, we constructed an array of simple leaf-shaped items and a single ellipsoidal target ‘prey’. We set these items in two light environments: strongly directional ‘sunny’ and more diffuse ‘cloudy’. The target object was given the optimal pattern of countershading for one of these two environment types or displayed a uniform pattern. By measuring detection time and accuracy, we explored whether and how target detection depended on the match between the pattern of coloration on the target object and scene lighting. Detection times were longest when the countershading was appropriate to the illumination; incorrectly camouflaged targets were detected with a similar pattern of speed and accuracy to uniformly coloured targets. We conclude that structural changes in light environment, such as caused by differences in weather, do change the effectiveness of countershading camouflage
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Microscale Freeform Integration by Directed Self Assembly
Most solid freeform fabrication (SFF) manufacturing processes assemble uniform
components such as powder particles or polymer chains to produce desired geometries. Their
capacity for producing highly functional parts (integrated actuation, sensing, and electronics)
will dramatically increase when multiple materials and functional subcomponents can be
automatically integrated. This paper addresses criteria for a system that integrates multiple
materials and components through computer-controlled self-assembly. It builds complex systems
from layers of self-assembled micro-components. The paper will address implementation
methods, present a concept demonstration, and consider its application to micro-thermoelectric
systems. This manufacturing process can be enhanced further through integration with mature
additive processes.Mechanical Engineerin
Rethinking geopolitical ambition: an analysis of India and its role in the United Nations Security Council
Soft power is a significant aspect of India’s identity in the international community. Moreover, India has committed itself in being a cooperative, active member of the international community. In an alternative theory of power within the field of international relations, I argue that while soft power reasons that states are not only shaped by threats, bribes, persuasion, and co-optation, but also by norms. Strikingly, India was pushed by the United States and the Soviet Union to join the Security Council in 1950 and 1955 respectively as a permanent seat member. However, India refused these offers and instead, supported the People’s Republic China for the position. Since the early 1990s, India has actively pursued permanent membership to the Security Council and various reforms by convincing other countries to support its bid. Thus, in the case of India and its quest for permanent membership in the Security Council, an alternative way of thinking about soft power is the ability to serve as an effective player in international politics and influencing other countries’ long-standing positions and preferences on this matter
Rethinking geopolitical ambition: an analysis of India and its role in the United Nations Security Council
Soft power is a significant aspect of India’s identity in the international community. Moreover, India has committed itself in being a cooperative, active member of the international community. In an alternative theory of power within the field of international relations, I argue that while soft power reasons that states are not only shaped by threats, bribes, persuasion, and co-optation, but also by norms. Strikingly, India was pushed by the United States and the Soviet Union to join the Security Council in 1950 and 1955 respectively as a permanent seat member. However, India refused these offers and instead, supported the People’s Republic China for the position. Since the early 1990s, India has actively pursued permanent membership to the Security Council and various reforms by convincing other countries to support its bid. Thus, in the case of India and its quest for permanent membership in the Security Council, an alternative way of thinking about soft power is the ability to serve as an effective player in international politics and influencing other countries’ long-standing positions and preferences on this matter
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Effects of chronic and acute consumption of fruit- and vegetable-puree-based drinks on vasodilation, risk factors for CVD and the response as a result of the eNOS G298T polymorphism
The average UK adult consumes less than three portions of fruit and vegetables daily, despite evidence to suggest that consuming five portions daily could help prevent chronic diseases. It is recommended that fruit juice should only count as one of these portions, as juicing removes fibre and releases sugars. However, fruit juices contain beneficial compounds such as vitamin C and flavonoids and could be a useful source of dietary phytochemicals. Two randomised controlled cross-over intervention studies investigating the effects of chronic and acute consumption of commercially-available fruit- and vegetable-puree-based drinks (FVPD) on bioavailability, antioxidant status and CVD risk factors are described. Blood and urine samples were collected during both studies and vascular tone was measured using laser Doppler imaging. In the chronic intervention study FVPD consumption was found to significantly increase dietary carotenoids (P=0·001) and vitamin C (P=0·003). Plasma carotenoids were increased (P=0·001), but the increase in plasma vitamin C was not significant. There were no significant effects on oxidative stress, antioxidant status and other CVD risk factors. In the acute intervention study FVPD were found to increase total plasma nitrate and nitrite (P=0·001) and plasma vitamin C (P=0·002). There was no effect on plasma lipids or uric acid, but there was a lower glucose and insulin peak concentration after consumption of the FVPD compared with the sugar-matched control. There was a trend towards increased vasodilation following both chronic and acute FVPD consumption. All volunteers were retrospectively genotyped for the eNOS G298T polymorphism and the effect of genotype on the measurements is discussed. Overall, there was a non-significant trend towards increased endothelium-dependent vasodilation following both acute and chronic FVPD consumption. However, there was a significant time×treatment effect (P<0·05) of acute FVPD consumption in individuals with the GG variant of the eNOS gene
Effects of acute consumption of fruit and vegetable puree-based drinks on vasodilation and oxidative status
Epidemiological studies indicate that diets rich in fruits and vegetables (F&V) are protective against cardiovascular diseases (CVD). Pureed \&V products retain many beneficial components, including flavonoids, carotenoids, vitamin C and dietary fibres. This study aimed to establish the physiological effects of acute ingestion of F&V puree-based drink (FVPD) on vasodilation, antioxidant status, phytochemical bioavailability and other CVD risk factors. 24 Subjects, aged 30-70 years, completed the randomised, single-blind, controlled, crossover test meal study. Subjects consumed 400 ml FVPD, or fruit-flavoured sugar-matched control, after following a low-flavonoid diet for 5 days. Blood and urine samples were collected throughout the study day and vascular reactivity was assessed at 90-minute intervals using laser Doppler iontophoresis (LDI). FVPD significantly increased plasma vitamin C (P=0.002) and total nitrate/nitrite (P=0.001) concentrations. There was a near significant time by treatment effect on ex vivo LDL oxidation (P=0.068), with a longer lag phase after consuming FVPD. During the 6 hours after juice consumption the antioxidant capacity of plasma increased significantly (P=0.003) and there was a simultaneous increase in plasma and urinary phenolic metabolites (P=0.05). There were significantly lower glucose and insulin peaks after ingestion of FVPD compared with control (P=0.019 and P=0.003) and a trend towards increased endothelium-dependent vasodilation following FVPD consumption (P=0.061). Overall, FVPD consumption significantly increased plasma vitamin C and total nitrate/nitrite concentrations, with a trend towards increased endothelium-dependent vasodilation. Pureed F&V products are useful vehicles for increasing micronutrient status, plasma antioxidant capacity and in vivo NO generation, which may contribute to CVD risk reduction
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