44,276 research outputs found
Kinesthetic control simulator
A kinesthetic control simulator is reported that has a flat base upon which rests a support structure having a lower spherical surface for rotation on the base plate with columns which support a platform above the support structure at a desired location with respect to the center of curvature of the spherical surface. A handrail is at approximately the elevation of the hips of the operator above the platform with a ring attached to the support structure which may be used to limit the angle of tilt. Five degree freedom-of-motion can be obtained by utilizing an air pad structure for support of the control simulator
Helioseismic Ring Analysis of CME Source Regions
We apply the ring diagram technique to source regions of halo coronal mass
ejections (CMEs) to study changes in acoustic mode parameters before, during,
and after the onset of CMEs. We find that CME regions associated with a low
value of magnetic flux have line widths smaller than the quiet regions implying
a longer life-time for the oscillation modes. We suggest that this criterion
may be used to forecast the active regions which may trigger CMEs.Comment: Accepted for publication in J. Astrophys. Astr. Also available at
http://www2.nso.edu/staff/sushant/paper.htm
Neural differentiation is moderated by age in scene- but not face-selective cortical regions
The aging brain is characterized by neural dedifferentiation, an apparent decrease in the functional selectivity of category-selective cortical regions. Age-related reductions in neural differentiation have been proposed to play a causal role in cognitive aging. Recent findings suggest, however, that age-related dedifferentiation is not equally evident for all stimulus categories and, additionally, that the relationship between neural differentiation and cognitive performance is not moderated by age. In light of these findings, in the present experiment, younger and older human adults (males and females) underwent fMRI as they studied words paired with images of scenes or faces before a subsequent memory task. Neural selectivity was measured in two scene-selective (parahippocampal place area (PPA) and retrosplenial cortex (RSC)] and two face-selective [fusiform face area (FFA) and occipital face area (OFA)] regions using both a univariate differentiation index and multivoxel pattern similarity analysis. Both methods provided highly convergent results, which revealed evidence of age-related reductions in neural dedifferentiation in scene-selective but not face-selective cortical regions. Additionally, neural differentiation in the PPA demonstrated a positive, age-invariant relationship with subsequent source memory performance (recall of the image category paired with each recognized test word). These findings extend prior findings suggesting that age-related neural dedifferentiation is not a ubiquitous phenomenon, and that the specificity of neural responses to scenes is predictive of subsequent memory performance independently of age
Equation of state for hard sphere fluids with and without Kac tails
In this note, we propose a simple derivation of the one dimensional hard rod
equation of state, with and without a Kac tail (appended long range and weak
potential). The case of hard spheres in higher dimension is also addressed and
it is shown there that our arguments --which avoid any mathematical
complication-- allow to recover the virial form of the equation of state in a
direct way.Comment: pedagogical pape
Serving children: the impact of poverty on children's experiences of services
This study arose from the identification of a gap in knowledge and corresponding need for the development of a better contemporary understanding of children's experiences of poverty. Focusing on children aged 10 - 14 years, the study aimed to provide a perspective on the lives of children and young people affected by poverty in Scotland through comparing the experiences of children living in poverty with those more economically advantaged
Spin-guides and spin-splitters: Waveguide analogies in one-dimensional spin chains
Here we show a direct mapping between waveguide theory and spin chain
transport, opening an alternative approach to quantum information transport in
the solid-state. By applying temporally varying control profiles to a spin
chain, we design a virtual waveguide or 'spin-guide' to conduct individual spin
excitations along defined space-time trajectories of the chain. We explicitly
show that the concepts of confinement, adiabatic bend loss and beamsplitting
can be mapped from optical waveguide theory to spin-guides (and hence
'spin-splitters'). Importantly, the spatial scale of applied control pulses is
required to be large compared to the inter-spin spacing, and thereby allowing
the design of scalable control architectures.Comment: 5 figure
Medical professionalism: more than fitness to practise
The General Medical Council (GMC) and the Medical Schools Council have produced guidance on professional behaviour for medical schools and students. The guidance focuses particularly on fitness to practise.While fitness to practise is vital for the protection of patients, we argue that it is only one aspect involved in the teaching and learning of professionalism
A Large Cross-Sectional Community-Based Study of Newborn Care Practices in Southern Tanzania
Despite recent improvements in child survival in sub-Saharan Africa, neonatal mortality rates remain largely unchanged. This study aimed to determine the frequency of delivery and newborn-care practices in southern Tanzania, where neonatal mortality is higher than the national average. All households in five districts of Southern Tanzania were approached to participate. Of 213,220 female residents aged 13-49 years, 92% participated. Cross-sectional, retrospective data on childbirth and newborn care practices were collected from 22,243 female respondents who had delivered a live baby in the preceding year. Health facility deliveries accounted for 41% of births, with nearly all non-facility deliveries occurring at home (57% of deliveries). Skilled attendants assisted 40% of births. Over half of women reported drying the baby and over a third reported wrapping the baby within 5 minutes of delivery. The majority of mothers delivering at home reported that they had made preparations for delivery, including buying soap (84%) and preparing a cloth for drying the child (85%). Although 95% of these women reported that the cord was cut with a clean razor blade, only half reported that it was tied with a clean thread. Furthermore, out of all respondents 10% reported that their baby was dipped in cold water immediately after delivery, around two-thirds reported bathing their babies within 6 hours of delivery, and 28% reported putting something on the cord to help it dry. Skin-to-skin contact between mother and baby after delivery was rarely practiced. Although 83% of women breastfed within 24 hours of delivery, only 18% did so within an hour. Fewer than half of women exclusively breastfed in the three days after delivery. The findings suggest a need to promote and facilitate health facility deliveries, hygienic delivery practices for home births, delayed bathing and immediate and exclusive breastfeeding in Southern Tanzania to improve newborn health
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