49,494 research outputs found
National level promotion of physical activity: results from England's ACTIVE for LIFE campaign.
STUDY OBJECTIVE: To assess the impact of a national campaign on awareness of the campaign, change in knowledge of physical activity recommendations and self reported physical activity. DESIGN: three year prospective longitudinal survey using a multi-stage, cluster random probability design to select participants. SETTING: England. PARTICIPANTS: A nationally representative sample of 3189 adults aged 16-74 years. MAIN OUTCOME MEASURES: Awareness of the advertising element of the campaign, changes in knowledge of physical activity recommendations for health and self reported physical activity. RESULTS: 38% of participants were aware of the main advertising images, assessed six to eight months after the main television advertisement. The proportion of participants knowledgeable about moderate physical activity recommendations increased by 3.0% (95% CI: 1.4%, 4.5%) between waves 1 and 2 and 3.7% (95% CI: 2.1%, 5.3%) between waves 1 and 3. The change in proportion of active people between baseline and waves 1 and 2 was -0.02 (95% CI: -2.0 to +1.7) and between waves 1 and 3 was -9.8 (-7.9 to -11.7). CONCLUSION: The proportion of participants who were knowledgeable about the new recommendations, increased significantly after the campaign. There was however, no significant difference in knowledge by awareness of the main campaign advertisement. There is no evidence that ACTIVE for LIFE improved physical activity, either overall or in any subgroup
Photoresist patterned thick-film piezoelectric elements on silicon
A fundamental limitation of screen printing is the achievable alignment accuracy and resolution. This paper presents details of a thick-resist process that improves both of these factors. The technique involves exposing/developing a thick resist to form the desired pattern and then filling the features with thick film material using a doctor blading process. Registration accuracy comparable with standard photolithographic processes has been achieved resulting in minimum feature sizes of <50 ?m and a film thickness of 100 ?m. Piezoelectric elements have been successfully poled on a platinised silicon wafer with a measured d 33 value of 60 pCN?1
Tracing Galaxy Assembly: Tadpole Galaxies in the Hubble Ultra Deep Field
In the Hubble Ultra Deep Field (HUDF) an abundance of galaxies is seen with a
knot at one end plus an extended tail, resembling a tadpole. These "tadpole
galaxies" appear dynamically unrelaxed--presumably in an early merging
state--where tidal interactions likely created the distorted knot-plus-tail
morphology. Here we systematically select tadpole galaxies from the HUDF and
study their properties as a function of their photometric redshifts. In a
companion HUDF variability study, Cohen et al. (2005) revealed a total of 45
variable objects believed to be Active Galactic Nuclei (AGN). Here we show that
this faint AGN sample has no overlap with the tadpole galaxy sample, as
predicted by theoretical work. The tadpole morphology--combined with the lack
of overlap with the variable objects--supports the idea that these galaxies are
in the process of an early-stage merger event, i.e., at a stage that likely
precedes the "turn-on" of any AGN component and the onset of any point-source
variability.Comment: 7 pages, 4 figures. Accepted for publication by Astrophysical Journa
Laser frequency locking by direct measurement of detuning
We present a new method of laser frequency locking in which the feedback
signal is directly proportional to the detuning from an atomic transition, even
at detunings many times the natural linewidth of the transition. Our method is
a form of sub-Doppler polarization spectroscopy, based on measuring two Stokes
parameters ( and ) of light transmitted through a vapor cell. This
extends the linear capture range of the lock loop by up to an order of
magnitude and provides equivalent or improved frequency discrimination as other
commonly used locking techniques.Comment: 4 pages, 4 figures Revte
Photoinduced charge and spin dynamics in strongly correlated electron systems
Motivated by photoinduced phase transition in manganese oxides, charge and
spin dynamics induced by photoirradiation are examined. We calculate the
transient optical absorption spectra of the extended double-exchange model by
the density matrix renormalization group (DMRG) method. A charge-ordered
insulating (COI) state becomes metallic just after photoirradiation, and the
system tends to recover the initial COI state. The recovery is accompanied with
remarkable suppression of an antiferromagnetic correlation in the COI state.
The DMRG results are consistent with recent pump-probe spectroscopy data.Comment: 5 pages, 4 figure
Magnetic resonance within vortex cores in the B phase of superfluid He
We investigate a magnetic susceptibility of vortices in the B phase of
multicomponent triplet superfluid He focusing on a contribution of bound
fermionic states localized within vortex cores. Several order parameter
configurations relevant to different types of quantized vortices in He B
are considered. It is shown quite generally that an ac magnetic susceptibility
has a sharp peak at the frequency corresponding to the energy of interlevel
spacing in the spectrum of bound fermions. We suggest that measuring of a
magnetic resonance within vortex cores can provide a direct probe of a discrete
spectrum of bound vortex core excitations
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