4,692 research outputs found

    The Viscosity and Thermal Conductivity Coefficients of Dilute Neon, Krypton, and Xenon

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    Viscosity and thermoconductivity coefficients of dilute neon, krypton, and xeno

    Looking and Thinking: How individuals with Williams syndrome make judgements about mental states

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    Individuals with the neuro-developmental disorder Williams syndrome (WS) are characterised by a combination of features which makes this group vulnerable socially, including mild-moderate cognitive difficulties, pro-social drive, and indiscriminate trust. The purpose of this study was to explore a key socio-communicative skill in individuals with WS, namely, mental state recognition abilities. We explored this skill in a detailed way by looking at how well individuals with WS recognise complex everyday mental states, and how they allocate their attention while making these judgements. Participants with WS were matched to two typically developing groups for comparison purposes, a verbal ability matched group and a chronological age matched group. While eye movements were recorded, participants were shown displays of eight different mental states in static and dynamic form, and they performed a forced-choice judgement on the mental state. Mental states were easier to recognise in dynamic form rather than static form. Mental state recognition ability for individuals with WS was poorer than expected by their chronological age, and at the level expected by their verbal ability. However, the pattern of mental state recognition for participants with WS varied according to mental state, and we found some interesting links between ease/difficulty recognising some mental states (worried/do not trust) and the classic behavioural profile associated with WS (high anxiety/indiscriminate trust). Furthermore, eye tracking data revealed that participants with WS allocated their attention atypically, with less time spent attending the information from the face regions. This challenges the widely held understanding of WS being associated with prolonged face and eye gaze, and indicates that there is more heterogeneity within this disorder in terms of socio-perception than previous reports would suggest

    Insulin clearance and the incidence of type 2 diabetes in Hispanics and African Americans: the IRAS Family Study.

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    ObjectiveWe aimed to identify factors that are independently associated with the metabolic clearance rate of insulin (MCRI) and to examine the association of MCRI with incident type 2 diabetes in nondiabetic Hispanics and African Americans.Research design and methodsWe investigated 1,116 participants in the Insulin Resistance Atherosclerosis Study (IRAS) Family Study with baseline examinations from 2000 to 2002 and follow-up examinations from 2005 to 2006. Insulin sensitivity (S(I)), acute insulin response (AIR), and MCRI were determined at baseline from frequently sampled intravenous glucose tolerance tests. MCRI was calculated as the ratio of the insulin dose over the incremental area under the curve of insulin. Incident diabetes was defined as fasting glucose ≥126 mg/dL or antidiabetic medication use by self-report.ResultsWe observed that S(I) and HDL cholesterol were independent positive correlates of MCRI, whereas fasting insulin, fasting glucose, subcutaneous adipose tissue, visceral adipose tissue, and AIR were independent negative correlates (all P < 0.05) at baseline. After 5 years of follow-up, 71 (6.4%) participants developed type 2 diabetes. Lower MCRI was associated with a higher risk of incident diabetes after adjusting for demographics, lifestyle factors, HDL cholesterol, indexes of obesity and adiposity, and insulin secretion (odds ratio 2.01 [95% CI 1.30-3.10], P = 0.0064, per one-SD decrease in loge-transformed MCRI).ConclusionsOur data showed that lower MCRI predicts the incidence of type 2 diabetes

    Analysis of lower limb internal kinetics and electromyography in elite race walking.

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    The aim of this study was to analyse lower limb joint moments, powers and electromyography patterns in elite race walking. Twenty international male and female race walkers performed at their competitive pace in a laboratory setting. The collection of ground reaction forces (1000 Hz) was synchronised with two-dimensional high-speed videography (100 Hz) and electromyography of seven lower limb muscles (1000 Hz). As well as measuring key performance variables such as speed and stride length, normalised joint moments and powers were calculated. The rule in race walking which requires the knee to be extended from initial contact to midstance effectively made the knee redundant during stance with regard to energy generation. Instead, the leg functioned as a rigid lever which affected the role of the hip and ankle joints. The main contributors to energy generation were the hip extensors during late swing and early stance, and the ankle plantarflexors during late stance. The restricted functioning of the knee during stance meant that the importance of the swing leg in contributing to forward momentum was increased. The knee flexors underwent a phase of great energy absorption during the swing phase and this could increase the risk of injury to the hamstring muscles

    Kinematic characteristics of elite men's 50 km race walking.

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    Race walking is an endurance event which also requires great technical ability, particularly with respect to its two distinguishing rules. The 50 km race walk is the longest event in the athletics programme at the Olympic Games. The aims of this observational study were to identify the important kinematic variables in elite men's 50 km race walking, and to measure variation in those variables at different distances. Thirty men were analysed from video data recorded during a World Race Walking Cup competition. Video data were also recorded at four distances during the European Cup Race Walking and 12 men analysed from these data. Two camcorders (50 Hz) recorded at each race for 3D analysis. The results of this study showed that walking speed was associated with both step length (r=0.54,P=0.002) and cadence (r=0.58,P=0.001). While placing the foot further ahead of the body at heel strike was associated with greater step lengths (r=0.45,P=0.013), it was also negatively associated with cadence (r= -0.62,P<0.001). In the World Cup, knee angles ranged between 175 and 186° at initial contact and between 180 and 195° at midstance. During the European Cup, walking speed decreased significantly (F=9.35,P=0.002), mostly due to a decrease in step length between 38.5 and 48.5 km (t=8.59,P=0.014). From this study, it would appear that the key areas a 50 km race walker must develop and coordinate are step length and cadence, although it is also important to ensure legal walking technique is maintained with the onset of fatigue

    Photoresponse of PbS nanoparticles-quaterthiophene films prepared by gaseous deposition as probed by XPS

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    Cataloged from PDF version of article.Semiconducting lead sulfide (PbS) nanoparticles were cluster beam deposited into evaporated quaterthiophene (4T) organic films, which in some cases were additionally modified by simultaneous 50 eV acetylene ion bombardment. Surface chemistry of these nanocomposite films was first examined using standard x-ray photoelectron spectroscopy (XPS). XPS was also used to probe photoinduced shifts in peak binding energies upon illumination with a continuous wave green laser and the magnitudes of these peak shifts were interpreted as changes in relative photoconductivity. The four types of films examined all displayed photoconductivity: 4T only, 4T with acetylene ions, 4T with PbS nanoparticles, and 4T with both PbS nanoparticles and acetylene ions. Furthermore, the ion-modified films displayed higher photoconductivity, which was consistent with enhanced bonding within the 4T organic matrix and between 4T and PbS nanoparticles. PbS nanoparticles displayed higher photoconductivity than the 4T component, regardless of ion modification. (C) 2012 American Vacuum Society

    Valuing the economic benefits of species recovery programmes

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    1. Accounting for the values placed on nature by the public is key to successful policies in reversing ongoing biodiversity declines. However, biodiversity values are rarely included in policy decisions, resulting in poorer outcomes for people and nature. 2. Our paper addresses an important evidence gap related to the non-availability of values for appraising large-scale policies and investment programmes for species recovery and habitat improvement at the national level. 3. We use a stated preference choice modelling approach to estimate household preferences and Willingness to Pay for species recovery and habitat improvement over a wide range of habitats in England. 4. The framing of our stated preference study is crucial to the evidence we develop. Within the study, we define species recovery as incremental improvements to habitat quality and present respondents with choices between conservation policy options that improve different habitat types. We then use the response data to estimate values for habitat quality improvements, and the associated improvements to species presence and abundance. We are thus able to estimate economic benefits for ‘wild species recovery’ simultaneously across a wide range of habitat types. 5. Willingness to pay values for habitat improvement was found to be highest for improvements from ‘moderate’ to ‘full’ species recovery by 2042; and for habitat types which have relatively low current extents in England, such as lowland fens. 6. Policy Implications: biodiversity policy designers can make use of stated preference methods to guide decisions over which aspects of biodiversity targets to focus more resources on, since this enables policy to reflect public preferences, and thus engages higher public support for conservation. In our specific data and context, this implies prioritising the restoration of species recovery to high levels and focussing resources on scarcer rather than more abundant habitat types
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