466 research outputs found
Is Foundational Movement Skill Competency Important for Keeping Children Physically Active and at a Healthy Weight?
This longitudinal study examines the associations between foundational movement skills (FMS) competency, moderate-to-vigorous physical activity (MVPA) and weight status among children (n = 75) attending preschools in deprived areas from early to late childhood. Twelve FMS were assessed using the Children’s Activity and Movement in Preschool Motor Skills Protocol and video analysis. Physical activity was measured via hip-mounted accelerometry. Data was collected over a five-year period, with Baseline Follow Up data collected between 2010 and 2015. There was an overall pattern of increase for total, object-control and locomotor scores between Baseline and Follow-Up. Conversely, there was an overall pattern of decline for MVPA among participants. There was a positive significant (p < 0.05) association between total and locomotor scores and MVPA at Baseline. However, these associations weakened over time and no significant associations were found at Follow-Up. Baseline competency failed to predict Follow-Up MVPA or weight status. Likewise, Baseline MVPA was not found to be a predictor of Follow-Up FMS competency. Further longitudinal research is required to explore these associations among children from highly deprived areas. Future interventions may require a more holistic approach to improving FMS competency and increasing PA in order to account for the number of variables that can affect these outcomes
Conical refraction with low-coherence light sources
We report on conical refraction (CR) with low-coherence light sources, such as light-emitting diodes and decoherentized HeNe laser radiation, and demonstrate different CR patterns. In our experiments, a variation of the pinhole sizes from 25 to 100 µm and the distances to pinhole from 50 to 5 cm reduced spatial coherence of radiation that resulted in the disappearance of the dark Poggendorff’s ring in the Lloyd’s plane. This is attributed to the interference nature of the Lloyd’s distribution and found to be in excellent agreement with the paraxial dual-cone model of conical refraction
Fully porous GaN p-n junctions fabricated by Chemical Vapor Deposition: a green technology towards more efficient LEDs
Producción CientíficaPorous GaN based LEDs produced by corrosion etching techniques
demonstrated enhanced light extraction efficiency in the past.
However, these fabrication techniques require further postgrown
processing steps, which increase the price of the final system. In
this paper, we review the process followed towards the fabrication
of fully porous GaN p-n junctions directly during the growth step,
using a sequential chemical vapor deposition (CVD) process to
produce the different layers that form the p-n junction.Junta de Castilla y León (programa de apoyo a proyectos de investigación – Ref. VA302U13
Off-limb (spicule) DEM distribution from SoHO/SUMER observations
In the present work we derive a Differential Emission Measure (DEM) dis-
tribution from a region dominated by spicules. We use spectral data from the
Solar Ultraviolet Measurements of Emitted Radiation (SUMER) spectrometer
on-board the Solar Heliospheric Observatory (SoHO) covering the entire SUMER
wavelength range taken off-limb in the Northern polar coronal hole to construct
this DEM distribution using the CHIANTI atomic database. This distribution is
then used to study the thermal properties of the emission contributing to the
171 {\AA} channel in the Atmospheric Imaging Assembly (AIA) on-board the Solar
Dynamics Observatory (SDO). From our off-limb DEM we found that the radiance in
the AIA 171 {\AA} channel is dominated by emission from the Fe ix 171.07 {\AA}
line and has sparingly little contribution from other lines. The product of the
Fe ix 171.07 {\AA} line contribution function with the off-limb DEM was found
to have a maximum at logTmax (K) = 5.8 indicating that during spicule
observations the emission in this line comes from plasma at transition region
temperatures rather than coronal. For comparison, the same product with a quiet
Sun and prominence DEM were found to have a maximum at logT max (K) = 5.9 and
logTmax (K) = 5.7, respectively. We point out that the interpretation of data
obtained from the AIA 171 {\AA} filter should be done with foreknowledge of the
thermal nature of the observed phenomenon. For example, with an off-limb DEM we
find that only 3.6% of the plasma is above a million degrees, whereas using a
quiet Sun DEM, this contribution rises to 15%.Comment: 12 pages, 6 figures accepted by Solar Physic
Merit, Tenure, and Bureaucratic Behavior: Evidence From a Conjoint Experiment in the Dominican Republic
Bureaucratic behavior in developing countries remains poorly understood. Why do some
public servants – yet not others – work hard to deliver public services, misuse state
resources, and/or participate in electoral mobilization? A classic answer comes from Weber:
bureaucratic structures shift behavior towards integrity, neutrality, and commitment to
public service. Our paper conducts the first survey experimental test of the effects of
bureaucratic structures. It does so through a conjoint experiment with public servants in the
Dominican Republic. Looking at merit examinations and job stability, we find that Weber
was right – but only partially. Recruitment by examination curbs corruption and political
services by bureaucrats, while enhancing work motivation. Job stability, by contrast, only
decreases political services: tenured bureaucrats are less likely to participate in electoral
mobilization. Examinations thus enhance the quality of bureaucracy (motivation and lower
corruption) and democracy (electoral competition); job stability only enhances the quality
of democracy
Herschel/HIFI observations of O-rich AGB stars : molecular inventory
Spectra, taken with the heterodyne instrument, HIFI, aboard the Herschel
Space Observatory, of O-rich asymptotic giant branch (AGB) stars which form
part of the guaranteed time key program HIFISTARS are presented. The aim of
this program is to study the dynamical structure, mass-loss driving mechanism,
and chemistry of the outflows from AGB stars as a function of chemical
composition and initial mass.
We used the HIFI instrument to observe nine AGB stars, mainly in the H2O and
high rotational CO lines We investigate the correlation between line
luminosity, line ratio and mass-loss rate, line width and excitation energy.
A total of nine different molecules, along with some of their isotopologues
have been identified, covering a wide range of excitation temperature. Maser
emission is detected in both the ortho- and para-H2O molecules. The line
luminosities of ground state lines of ortho- and para-H2O, the high-J CO and
NH3 lines show a clear correlation with mass-loss rate. The line ratios of H2O
and NH3 relative to CO J=6-5 correlate with the mass-loss rate while ratios of
higher CO lines to the 6-5 is independent of it. In most cases, the expansion
velocity derived from the observed line width of highly excited transitions
formed relatively close to the stellar photosphere is lower than that of lower
excitation transitions, formed farther out, pointing to an accelerated outflow.
In some objects, the vibrationally excited H2O and SiO which probe the
acceleration zone suggests the wind reaches its terminal velocity already in
the innermost part of the envelope, i.e., the acceleration is rapid.
Interestingly, for R Dor we find indications of a deceleration of the outflow
in the region where the material has already escaped from the star.Comment: 6 Figures in the main paper + 12 further figures in the appendix (to
be printed in electronic form) Accepted for publication by A&
Towards improved decision support in the assessment and management of pain for people with dementia in hospital: a systematic meta-review and observational study
This is the final version. Available from NIHR Journals Library via the DOI in this record.Background
Pain and dementia are common in older people, and impaired cognitive abilities make it difficult for them to communicate their pain. Pain, if poorly managed, impairs health and well-being. Accurate pain assessment in this vulnerable group is challenging for hospital staff, but essential for appropriate management. Robust methods for identifying, assessing and managing pain are needed.
Aims and objectives
Two studies were undertaken to inform the development of a decision support tool to aid hospital staff in the recognition, assessment and management of pain. The first was a meta-review of systematic reviews of observational pain assessment instruments with three objectives: (1) to identify the tools available to assess pain in adults with dementia; (2) to identify in which settings they were used and with what patient populations; and (3) to assess their reliability, validity and clinical utility. The second was a multisite observational study in hospitals with four objectives: (1) to identify information currently used by clinicians when detecting and managing pain in patients with dementia; (2) to explore existing processes for detecting and managing pain in these patients; (3) to identify the role (actual/potential) of carers in this process; and (4) to explore the organisational context in which health professionals operate. Findings also informed development of health economics data collection forms to evaluate the implementation of a new decision support intervention in hospitals.
Methods
For the meta-review of systematic reviews, 12 databases were searched. Reviews of observational pain assessment instruments that provided psychometric data were included. Papers were quality assessed and data combined using narrative synthesis. The observational study used an ethnographic approach in 11 wards in four UK hospitals. This included non-participant observation of 31 patients, audits of patient records, semistructured interviews with 52 staff and four carers, informal conversations with staff and carers and analysis of ward documents and policies. Thematic analysis of the data was undertaken by the project team.
Results
Data from eight systematic reviews including 28 tools were included in the meta-review. Most tools showed moderate to good reliability, but information about validity, feasibility and clinical utility was scarce. The observational study showed complex ward cultures and routines, with variations in time spent with patients, communication patterns and management practices. Carer involvement was rare. No pain decision support tools were observed in practice. Information about pain was elicited in different ways, at different times, by different health-care staff and recorded in separate documents. Individual staff made sense of patients’ pain by creating their own ‘overall picture’ from available information.
Limitations
Grey literature and non-English-language papers were excluded from the meta-review. Sample sizes in the observational study were smaller than planned owing to poor documentation of patients’ dementia diagnoses, gatekeeping by staff and difficulties in gaining consent/assent. Many patients had no or geographically distant carers, or a spouse who was too unwell and/or reluctant to participate.
Conclusions
No single observational pain scale was clearly superior to any other. The traditional linear concept of pain being assessed, treated and reassessed by single individuals did not ‘fit’ with clinical reality. A new approach enabling effective communication among patients, carers and staff, centralised recording of pain-related information, and an extended range of pain management interventions is proposed [Pain And Dementia Decision Support (PADDS)]. This was not tested with users, but a follow-on study aims to codesign PADDS with carers and clinicians, then introduce education on staff/patient/carer communications and use of PADDS within a structured implementation plan. PADDS will need to be tested in differing ward contexts.National Institute for Health Research Health Services and Delivery Research programm
Electron beam charging of insulators: A self-consistent flight-drift model
International audienceElectron beam irradiation and the self-consistent charge transport in bulk insulating samples are described by means of a new flight-drift model and an iterative computer simulation. Ballistic secondary electron and hole transport is followed by electron and hole drifts, their possible recombination and/or trapping in shallow and deep traps. The trap capture cross sections are the Poole-Frenkel-type temperature and field dependent. As a main result the spatial distributions of currents j(x,t), charges, the field F(x,t) and the potential slope V(x,t) are obtained in a self-consistent procedure as well as the time-dependent secondary electron emission rate sigma(t) and the surface potential V0(t) For bulk insulating samples the time-dependent distributions approach the final stationary state with j(x,t)=const=0 and sigma=1. Especially for low electron beam energies E0=4 keV the incorporation of mainly positive charges can be controlled by the potential VG of a vacuum grid in front of the target surface. For high beam energies E0=10, 20, and 30 keV high negative surface potentials V0=−4, −14, and −24 kV are obtained, respectively. Besides open nonconductive samples also positive ion-covered samples and targets with a conducting and grounded layer (metal or carbon) on the surface have been considered as used in environmental scanning electron microscopy and common SEM in order to prevent charging. Indeed, the potential distributions V(x) are considerably small in magnitude and do not affect the incident electron beam neither by retarding field effects in front of the surface nor within the bulk insulating sample. Thus the spatial scattering and excitation distributions are almost not affected
Fundamental movement skills in relation to weekday and weekend physical activity in preschool children.
OBJECTIVES: To examine associations between fundamental movement skills and weekday and weekend physical activity among preschool children living in deprived communities. DESIGN: Cross-sectional observation study. METHODS: Six locomotor skills and 6 object-control skills were video-assessed using The Children's Activity and Movement in Preschool Study Motor Skills Protocol. Physical activity was measured via hip-mounted accelerometry. A total of 99 children (53% boys) aged 3-5 years (M 4.6, SD 0.5) completed all assessments. Multilevel mixed regression models were used to examine associations between fundamental movement skills and physical activity. Models were adjusted for clustering, age, sex, standardised body mass index and accelerometer wear time. RESULTS: Boys were more active than girls and had higher object-control skill competency. Total skill score was positively associated with weekend moderate-to-vigorous physical activity (p=0.034) but not weekday physical activity categories (p>0.05). When subdomains of skills were examined, object-control skills was positively associated with light physical activity on weekdays (p=0.008) and with light (p=0.033), moderate-to-vigorous (p=0.028) and light- and moderate-to-vigorous (p=0.008) physical activity at weekends. Locomotor skill competency was positively associated with moderate-to-vigorous physical activity on weekdays (p=0.016) and light physical activity during the weekend (p=0.035). CONCLUSIONS: The findings suggest that developing competence in both locomotor and object-control skills may be an important element in promoting an active lifestyle in young children during weekdays and at weekends
Early development of spasticity following stroke: a prospective, observational trial
This study followed a cohort of 103 patients at median 6 days, 6 and 16 weeks after stroke and recorded muscle tone, pain, paresis, Barthel Index and quality of life score (EQ-5D) to identify risk-factors for development of spasticity. 24.5% of stroke victims developed an increase of muscle tone within 2 weeks after stroke. Patients with spasticity had significantly higher incidences of pain and nursing home placement and lower Barthel and EQ-5D scores than patients with normal muscle tone. Early predictive factors for presence of severe spasticity [modified Ashworth scale score (MAS) ≥3] at final follow-up were moderate increase in muscle tone at baseline and/or first follow-up (MAS = 2), low Barthel Index at baseline, hemispasticity, involvement of more than two joints at first follow-up, and paresis at any assessment point. The study helps to identify patients at highest risk for permanent and severe spasticity, and advocates for early treatment in this group
- …