To send content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about sending content to .
To send content items to your Kindle, first ensure email@example.com
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about sending to your Kindle.
Note you can select to send to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
To describe the modification and validation of an existing instrument, the Environment and Policy Assessment and Observation (EPAO), to better capture provider feeding practices.
Modifications to the EPAO were made, validity assessed through expert review, pilot tested and then used to collect follow-up data during a two-day home visit from an ongoing cluster-randomized trial. Exploratory factor analysis investigated the underlying factor structure of the feeding practices. To test predictive validity of the factors, multilevel mixed models examined associations between factors and child’s diet quality as captured by the Healthy Eating Index-2010 (HEI-2010) score (measured via the Dietary Observation in Childcare Protocol).
Family childcare homes (FCCH) in Rhode Island and North Carolina, USA.
The modified EPAO was pilot tested with fifty-three FCCH and then used to collect data in 133 FCCH.
The final three-factor solution (‘coercive control and indulgent feeding practices’, ‘autonomy support practices’, ‘negative role modelling’) captured 43 % of total variance. In multilevel mixed models adjusted for covariates, ‘autonomy support practices’ was positively associated with children’s diet quality. A 1-unit increase in the use of ‘autonomy support practices’ was associated with a 9·4-unit increase in child HEI-2010 score (P=0·001).
Similar to the parenting literature, constructs which describe coercive controlling practices and those which describe autonomy-supportive practices emerged. Given that diets of pre-schoolers in the USA remain suboptimal, teaching childcare providers about supportive feeding practices may help improve children’s diet quality.
This research aims to explore the submerged landscapes of the Pilbara of western Australia, using predictive archaeological modelling, airborne LiDAR, marine acoustics, coring and diver survey. It includes excavation and geophysical investigation of a submerged shell midden in Denmark to establish guidelines for the underwater discovery of such sites elsewhere.
The electron affinity of a semiconductor defines the relationship of the vacuum level and the semiconductor band structure. It is dependent on the atomic orbitals of the material and the surface termination. We report experimental and theoretical results that support the presence of a negative electron affinity on AlN and the Al rich AlGaN alloys. The GaN surface is found to exhibit a (positive) electron affinity of 3.3eV. The experimental measurements employ UV-photoemission spectroscopy on in situ gas-source MBE samples and on CVD samples. Theoretical results indicate that the (negative) electron affinity of AlN depends sensitively on the surface reconstruction and adatom termination. The experimental dependence of the electron affinity on alloy concentration is presented. The results indicate that AlGaN alloys with band gap similar or greater than that of diamond will exhibit a negative electron affinity. Field emission results are reported, and the characteristics are similar to those obtained from a diamond film. Issues related to cold cathode electronic devices based on NEA surfaces are noted.
Wide bandgap semiconductors such as diamond and the III-V nitrides of GaN and AIN exhibit small or even negative electron affinities. Recent results have shown that surface treatments will modify the electron affinity of diamond to cause a negative electron affinity (NEA). Results are presented which correlate the field emission from single crystal p-type (boron doped) diamond with the electron affinity of the surfaces. The field emission is explored for nitrogen doped polycrystalline films. The threshold for field emission is significantly higher than from p-type diamond, and in fact, most surfaces are severely damaged during the emission measurement. High resolution photo-electron emission microscopy (PEEM) and field emission electron microscopy (FEEM) are employed to determine the relation of the emission to the surface morphology. PEEM results presented for diamond indicate relatively uniform emission with increased intensity at protruding crystallite edges. Results are presented for cold cathodes fabricated from epitaxial nitrides grown on 6H-SiC.
This paper is a sequel to our previous paper investigating when arrivals see time averages (ASTA) in a stochastic model; i.e., when the steady-state distribution of an embedded sequence, obtained by observing a continuous-time stochastic process just prior to the points (arrivals) of an associated point process, coincides with the steady-state distribution of the observed process. The relation between the two distributions was also characterized when ASTA does not hold. These results were obtained using the conditional intensity of the point process given the present state of the observed process (assumed to be well defined) and basic properties of Riemann–Stieltjes integrals. Here similar results are obtained using the stochastic intensity associated with the martingale theory of point processes, as in Brémaud (1981). In the martingale framework, the ASTA result is almost an immediate consequence of the definition of a stochastic intensity. In a stationary framework, the results characterize the Palm distribution, but stationarity is not assumed here. Watanabe's (1964) martingale characterization of a Poisson process is also applied to establish a general version of anti–PASTA: if the points of the point process are appropriately generated by the observed process and the observed process is Markov with left-continuous sample paths, then ASTA implies that the point process must be Poisson.