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Free healthy breakfasts in primary schools: A cluster randomised controlled trial of a policy intervention in Wales, UK
Objective: The present study evaluated the impact of a national school programme of universal free healthy breakfast provision in Wales, UK.
Design: A cluster randomised controlled trial with repeated cross-sectional design and a 12-month follow-up. Primary outcomes were breakfast skipping, breakfast diet and episodic memory. Secondary outcomes were frequency of eating breakfast at home and at school, breakfast attitudes, rest-of-day diet and class behaviour.
Setting: Primary schools in nine local education authority areas.
Subjects: A total of 4350 students (aged 9–11 years) at baseline and 4472 at follow-up in 111 schools.
Results: Students in intervention schools reported significantly higher numbers of healthy food items consumed at breakfast and more positive attitudes towards breakfast eating at 12 months. Parents in intervention schools reported significantly higher rates of consumption of breakfast at school and correspondingly lower rates of breakfast consumption at home. No other significant differences were found.
Conclusions: The intervention did not reduce breakfast skipping; rather, pupils substituted breakfast at home for breakfast at school. However, there were improvements in children’s nutritional intake at breakfast time, if not the rest of the day, and more positive attitudes to breakfast, which may have implications for life-course dietary behaviours. There was no impact on episodic memory or classroom behaviour, which may require targeting breakfast skippers
Single spin universal Boolean logic
Recent advances in manipulating single electron spins in quantum dots have
brought us close to the realization of classical logic gates based on
representing binary bits in spin polarizations of single electrons. Here, we
show that a linear array of three quantum dots, each containing a single spin
polarized electron, and with nearest neighbor exchange coupling, acts as the
universal NAND gate. The energy dissipated during switching this gate is the
Landauer-Shannon limit of kTln(1/p) [T = ambient temperature and p = intrinsic
gate error probability]. With present day technology, p = 1E-9 is achievable
above 1 K temperature. Even with this small intrinsic error probability, the
energy dissipated during switching the NAND gate is only ~ 21 kT, while today's
nanoscale transistors dissipate about 40,000 - 50,000 kT when they switch
An integrated software system for geometric correction of LANDSAT MSS imagery
A system for geometrically correcting LANDSAT MSS imagery includes all phases of processing, from receiving a raw computer compatible tape (CCT) to the generation of a corrected CCT (or UTM mosaic). The system comprises modules for: (1) control of the processing flow; (2) calculation of satellite ephemeris and attitude parameters, (3) generation of uncorrected files from raw CCT data; (4) creation, management and maintenance of a ground control point library; (5) determination of the image correction equations, using attitude and ephemeris parameters and existing ground control points; (6) generation of corrected LANDSAT file, using the equations determined beforehand; (7) union of LANDSAT scenes to produce and UTM mosaic; and (8) generation of output tape, in super-structure format
Radiological Pitfalls in Patients with Inducible Dynamic Proptosis
We report two patients presenting with marked clinical unilateral enophthalmos who had positional variability and dynamic proptosis on valsalva. On orbital imaging, enophthalmos was not documented and in fact, globe proptosis of the same side was reported for one of the patients. During CT and MRI scanning patients are often instructed to hold their breath to eliminate motion artefact. This may inadvertently induce dynamic proptosis. The radiological pitfalls of imaging patients with inducible dynamic proptosis and how to identify such patients are discussed
Scanning Quantum Decoherence Microscopy
The use of qubits as sensitive magnetometers has been studied theoretically
and recent demonstrated experimentally. In this paper we propose a
generalisation of this concept, where a scanning two-state quantum system is
used to probe the subtle effects of decoherence (as well as its surrounding
electromagnetic environment). Mapping both the Hamiltonian and decoherence
properties of a qubit simultaneously, provides a unique image of the magnetic
(or electric) field properties at the nanoscale. The resulting images are
sensitive to the temporal as well as spatial variation in the fields created by
the sample. As an example we theoretically study two applications of this
technology; one from condensed matter physics, the other biophysics. The
individual components required to realise the simplest version of this device
(characterisation and measurement of qubits, nanoscale positioning) have
already been demonstrated experimentally.Comment: 11 pages, 5 low quality (but arXiv friendly) image
Resource Utilization Due to Breakthrough Pain in Patients With Chronic Painful Conditions
Objectives Primary: To capture healthcare resource consumption and work loss in a population of patients with chronic pain who have pain flares from one or more non-cancer conditions.
Secondary: To explore the relationship between anxiety, depression, and pain in this population
Perception of Breakthrough Pain in Patients with Chronic Painful Conditions
Objective: To understand how patients with chronic non-cancer pain define and describe pain flares
Renormalized Path Integral for the Two-Dimensional Delta-Function Interaction
A path-integral approach for delta-function potentials is presented.
Particular attention is paid to the two-dimensional case, which illustrates the
realization of a quantum anomaly for a scale invariant problem in quantum
mechanics. Our treatment is based on an infinite summation of perturbation
theory that captures the nonperturbative nature of the delta-function bound
state. The well-known singular character of the two-dimensional delta-function
potential is dealt with by considering the renormalized path integral resulting
from a variety of schemes: dimensional, momentum-cutoff, and real-space
regularization. Moreover, compatibility of the bound-state and scattering
sectors is shown.Comment: 26 pages. The paper was significantly expanded and numerous equations
were added for the sake of clarity; the main results and conclusions are
unchange
Redeveloping Derelict and Underused Historic City Areas: Evidence from a Survey of Real Estate Developers
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