Feasibility, Acceptability and Process Evaluation of a Physical Activity Intervention in Toddler aged Children: The TAP-A-LONG Study

Recent literature has suggested the importance of physical activity in early childhood such as during the toddler years (12 months - 3 years.) Despite this, most toddlers are not physically active. There is a need to determine the types of physical activity programs that would interest toddlers within the settings they spend a significant amount of time in (e.g., childcare center). Currently, data on the feasibility, implementation, and process evaluation of physical activity interventions in toddler age children attending childcare centers is lacking within the literature. Therefore, the purpose of the Toddler Activity Pilot (TAP-A-LONG) study was to examine the feasibility and acceptability of a four day per week, 10-week physical activity program in toddler aged children during the childcare day. Process evaluation data was collected daily during the entire 10-week study using a semi-structured questionnaire. Once per week on a randomly selected day, toddlers’ physical activity was assessed with accelerometers during the 10-minute intervention session or gross-motor playtime for the treatment and control group, respectively. Accelerometers were also worn for the duration of the full day during baseline, midpoint, and post. Participants were male (58%), white (46%), and lived in a household with married parents (58%). Toddlers’ average age was 25.0 ± 4.2 months. A total of 69.4% of the toddler population was recruited to participate in the study amongst the three participating centers (TAP = 37; CON = 13). During the 10-minute intervention session, toddlers in the treatment group spent 60.4 ± 22.0%, 28.7 ± 15.7%, and 10.9 ± 10.6% of time in sedentary (SED), light physical activity (LPA), and moderate-to-vigorous physical activity (MVPA), respectively. While control center spent 55.7 ± 18.8%, 35.9 ± 15.1, and 8.4 ± 8.0% in SED, LPA, and MVPA, respectively. For program quality, 76.7% and 62.0% of researcher and provider led intervention sessions were delivered clearly (i.e., directions were understandable to toddlers), respectively. The majority of intervention sessions held toddlers’ attention (60% of toddlers participated in at least half of the intervention). Overall, the high acceptability of our TAP-A-LONG intervention highlights the usefulness of physical activity interventions within the childcare setting

When is S=A/4?

Black hole entropy and its relation to the horizon area are considered. More precisely, the conditions and specifications that are expected to be required for the assignment of entropy, and the consequences that these expectations have when applied to a black hole are explored. In particular, the following questions are addressed: When do we expect to assign an entropy?; when are entropy and area proportional? and, what is the nature of the horizon? It is concluded that our present understanding of black hole entropy is somewhat incomplete, and some of the relevant issues that should be addressed in pursuing these questions are pointed out.Comment: 14 pages, no figures. Revtex file. Manuscript edited and discussion expanded. References added, conclusions unchanged. Version to be published in MPL

On Black Hole Scalar Hair in Asymptotically Anti de Sitter Spacetimes

The unexpected discovery of hairy black hole solutions in theories with scalar fields simply by considering asymptotically Anti de-Sitter, rather than asymptotically flat, boundary conditions is analyzed in a way that exhibits in a clear manner the differences between the two situations. It is shown that the trivial Schwarzschild Anti de Sitter becomes unstable in some of these situations, and the possible relevance of this fact for the ADS/CFT conjecture is pointed out.Comment: 12 pages. Published versio

Mass of Colored Black Holes

New results pertaining to colored static black hole solutions to the Einstein-Yang-Mills equations are obtained. The isolated horizons framework is used to define the concept of Hamiltonian Horizon Mass of the black hole. An unexpected relation between the ADM and Horizon masses of the black hole solution with the ADM mass of the corresponding Bartnik-McKinnon soliton is found. These results can be generalized to other non-linear theories and they suggest a general testing bed for the instability of the corresponding hairy black holes.Comment: 8 pages, no figures, Revtex file. Minor changes made to clarify some formulas. References updated. Final version to appear in PRD/15

A Possible Bifurcation in Atmospheres of Strongly Irradiated Stars and Planets

We show that under certain circumstances the differences between the absorption mean and Planck mean opacities can lead to multiple solutions for an LTE atmospheric structure. Since the absorption and Planck mean opacities are not expected to differ significantly in the usual case of radiative equilibrium, non-irradiated atmospheres, the most interesting situations where the effect may play a role are strongly irradiated stars and planets, and also possibly structures where there is a significant deposition of mechanical energy, such as stellar chromospheres and accretion disks. We have presented an illustrative example of a strongly irradiated giant planet where the bifurcation effect is predicted to occur for a certain range of distances from the star.Comment: 22 pages, 6 figures, submitted to Ap

Galactic periodicity and the oscillating G model

We consider the model involving the oscillation of the effective gravitational constant that has been put forward in an attempt to reconcile the observed periodicity in the galaxy number distribution with the standard cosmological models. This model involves a highly nonlinear dynamics which we analyze numerically. We carry out a detailed study of the bound that nucleosynthesis imposes on this model. The analysis shows that for any assumed value for $\Omega$ (the total energy density) one can fix the value of $\Omega_{\rm bar}$ (the baryonic energy density) in such a way as to accommodate the observational constraints coming from the $^4{\rm He}$ primordial abundance. In particular, if we impose the inflationary value $\Omega=1$ the resulting baryonic energy density turns out to be $\Omega_{\rm bar}\sim 0.021$. This result lies in the very narrow range $0.016 \leq \Omega_{\rm bar} \leq 0.026$ allowed by the observed values of the primordial abundances of the other light elements. The remaining fraction of $\Omega$ corresponds to dark matter represented by a scalar field.Comment: Latex file 29 pages with no figures. Please contact M.Salgado for figures. A more careful study of the model appears in gr-qc/960603

L and T Dwarf Models and the L to T Transition

Using a model for refractory clouds, a novel algorithm for handling them, and the latest gas-phase molecular opacities, we have produced a new series of L and T dwarf spectral and atmosphere models as a function of gravity and metallicity, spanning the \teff range from 2200 K to 700 K. The correspondence with observed spectra and infrared colors for early- and mid-L dwarfs and for mid- to late-T dwarfs is good. We find that the width in infrared color-magnitude diagrams of both the T and L dwarf branches is naturally explained by reasonable variations in gravity and, therefore, that gravity is the "second parameter" of the L/T dwarf sequence. We investigate the dependence of theoretical dwarf spectra and color-magnitude diagrams upon various cloud properties, such as particle size and cloud spatial distribution. In the region of the L$\to$T transition, we find that no one cloud-particle-size and gravity combination can be made to fit all the observed data. Furthermore, we note that the new, lower solar oxygen abundances of Allende-Prieto, Lambert, & Asplund (2002) produce better fits to brown dwarf data than do the older values. Finally, we discuss various issues in cloud physics and modeling and speculate on how a better correspondence between theory and observation in the problematic L$\to$T transition region might be achieved.Comment: accepted to the Astrophysical Journal, 21 figures (20 in color); spectral models in electronic form available at http://zenith.as.arizona.edu/~burrow