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Describe nutrition and physical activity practices, nutrition self-efficacy and barriers and food programme knowledge within Family Child Care Homes (FCCH) and differences by staffing.
Baseline, cross-sectional analyses of the Happy Healthy Homes randomised trial (NCT03560050).
FCCH in Oklahoma, USA.
FCCH providers (n 49, 100 % women, 30·6 % Non-Hispanic Black, 2·0 % Hispanic, 4·1 % American Indian/Alaska Native, 51·0 % Non-Hispanic white, 44·2 ± 14·2 years of age. 53·1 % had additional staff) self-reported nutrition and physical activity practices and policies, nutrition self-efficacy and barriers and food programme knowledge. Differences between providers with and without additional staff were adjusted for multiple comparisons (P < 0·01).
The prevalence of meeting all nutrition and physical activity best practices ranged from 0·0–43·8 % to 4·1–16·7 %, respectively. Average nutrition and physical activity scores were 3·2 ± 0·3 and 3·0 ± 0·5 (max 4·0), respectively. Sum nutrition and physical activity scores were 137·5 ± 12·6 (max 172·0) and 48·4 ± 7·5 (max 64·0), respectively. Providers reported high nutrition self-efficacy and few barriers. The majority of providers (73·9–84·7 %) felt that they could meet food programme best practices; however, knowledge of food programme best practices was lower than anticipated (median 63–67 % accuracy). More providers with additional staff had higher self-efficacy in family-style meal service than did those who did not (P = 0·006).
Providers had high self-efficacy in meeting nutrition best practices and reported few barriers. While providers were successfully meeting some individual best practices, few met all. Few differences were observed between FCCH providers with and without additional staff. FCCH providers need additional nutrition training on implementation of best practices.
The Galactic center, which serves as a paradigm of low-luminosity active galactic nuclei (LLAGN), hosts the Nuclear star cluster (NSC) that contains both young and more evolved stars. So far the population of the end-products of stellar evolution has not been observationally confirmed and studied, although there are hints of its presence. We study the distribution of interaction modes of a hypothetical population of neutron stars within the sphere of influence of the Sgr A* supermassive black hole (SMBH). The comparison of our models with future observations could be used to constrain the 3D structure of the Galactic center.
We present the very first detection of N2H+J = (1 – 0) and CH3OH(2k−1k) line emission on 5″ scales in the circumnuclear disk (CND) around Sgr A*. The emission matches the position and shape of the dark clouds in the near-infrared. Our findings suggest that these molecular clouds in the eastern CND are significantly colder and denser than the rest of the CND, and partially shocked. The research on these dark clouds will contribute to understanding the processes of star formation close to a supermassive black hole.
A fast moving infrared excess source (G2) which is widely interpreted as a core-less gas and dust cloud approaches Sagittarius A* (Sgr A*) on a presumably elliptical orbit. VLT Ks-band and Keck K′-band data result in clear continuum identifications and proper motions of this ∼19m Dusty S-cluster Object (DSO). In 2002-2007 it is confused with the star S63, but free of confusion again since 2007. Its near-infrared (NIR) colors and a comparison to other sources in the field speak in favor of the DSO being an IR excess star with photospheric continuum emission at 2 microns than a core-less gas and dust cloud. We also find very compact L′-band emission (<0.1″) contrasted by the reported extended (0.03″ up to ∼0.2″ for the tail) Brγ emission. The presence of a star will change the expected accretion phenomena, since a stellar Roche lobe may retain a fraction of the material during and after the peri-bothron passage.
The two Helios probes traveled at variable longitudinal and radial separations through the inner heliosphere. They collected most valuable high resolution plasma and magnetic field data for an entire solar cycle. The mission is still so successful that no other missions will collect the same kind of data in the next 20 years. One of the subjects studied after the success of the Helios mission was the identification of more than 390 shock waves driven by Interplanetary Coronal Mass Ejections (ICMEs). Combining the data from both probes, we make a statistical study for the extension of the shock waves in the interplanetary medium. For longitudinal separations of 90° we found a cutoff value at this angular separation. A shock has 50% of chance to be observed by both probes and the same probability for not being observed by two spacecrafts at the same time, when the angle between them is around 90°. We describe the dependence of the probability for shocks to be observed by both probes with decreasing spacecraft separation. Including plasma data from the ISEE-3 and IMP-8 spacecrafts improves our statistical evaluation substantially.
We present the adaptive optics assisted, near-infrared VLTI instrument GRAVITY for precision narrow-angle astrometry and interferometric phase referenced imaging of faint objects. With its two fibers per telescope beam, its internal wavefront sensors and fringe tracker, and a novel metrology concept, GRAVITY will not only push the sensitivity far beyond what is offered today, but will also advance the astrometric accuracy for UTs to 10 μas. GRAVITY is designed to work with four telescopes, thus providing phase referenced imaging and astrometry for 6 baselines simultaneously. Its unique capabilities and sensitivity will open a new window for the observation of a wide range of objects, and — amongst others — will allow the study of motion within a few times the event horizon size of the Galactic Center black hole.
We have studied the rate of oxygen diffusion through Sr2AlTaO6 (SAT), a buffer and dielectric layer used in high critical temperature superconducting (HTSC) structures. An epitaxial bilayer film of SAT on YBa2Cu3O7-δ (YBCO) was deposited onto an (001) oriented single crystal LaAlO3 substrate using the pulsed laser deposition technique. The rate of oxygen diffusion through the bilayer was investigated over the temperature range 415 to 675 °C by post deposition annealing individual sections of the bilayer in 1/3 atm of 18O enriched molecular oxygen gas. Secondary ion mass spectroscopy was used to depth profile 18O and 16O in each sample. Oxygen diffusion coefficients for SAT at 418, 510, 570 and 673 °C were determined to be roughly (0.93, 6.31, 26.6 and 75.3) × 10−16 cm2 s−1, respectively. Since these diffusion rates can limit oxygen intake into underlying YBCO films, SAT may be an inappropriate choice as a dielectric candidate for use in an HTSC multilayer device technology and will at best require development of suitable post annealing schemes to oxygenate underlying YBCO layers.
Nonalloyed, single crystal, oxide free Ge based ohmic contacts are almost atomically abrupt, have a smooth interface, and have the potential to be better understood. Ultra high vacuum electron beam evaporation is used to deposit a single crystal Ge film on GaAs and InGaP substrates. A large grain, highly oriented Au film or a poly crystalline Pd film with more randomly oriented grains was then deposited on the Ge. These films were characterized in the as grown condition by high resolution electron microscopy (HREM), double crystal x-ray diffraction (DXRD), Auger electron spectroscopy (AES), Rutherford back scattering (RBS) and scanning electron microscopy (SEM). The as deposited Ge film grown at 400°C on GaAs and at 350°C on InGaP are epitaxial with a smooth abrupt, oxide free interface. The highly oriented Au film deposited at 100°C had a smooth interface with the Ge with the orientation relationship (100)Au II (100)Ge and Au II [011 ]Ge or [0-1 1 ]Ge.
Using a magnetic field to confine the plasma closer to the cathode has been shown to be advantageous in dry etching technology since this yields a high degree of ionization at low pressures. We report here the results of a study of magnetron reactive ion etching of GaAs using a freon discharge. Various characterization techniques have been employed to understand the etching process and identify the extent of surface damage. The results show that magnetron etching is capable of yielding high etch rates with low damage.
The formation of low temperature Au-Ge contacts to n-GaAs is a two-step process. In the first step, the metals segregate into Au and Ge rich regions and the intermixing of the Au and Ge with the Ga and As causes a reduction in the barrier height. The second step occurs after extended annealing, during which time Au and Ge continue to diffuse into the substrate. An orthorhombic Au-Ga phase is formed and it is likely that other Au-Ga or Ge-As phases are formed. The length of the extended anneal is dependent upon the atomic percent of Ge in the film, with the 10 at. % Ge taking 6 hr., the 27 at. % Ge taking 3 hr. and the 50 at. % Ge taking 9 hr. to become ohmic. The 75 at. % Ge sample doesn’t show ohmic behavior even after 33 hr. of annealing. The metal-semiconductor interface configuration appears abrupt, showing no protrusions into the GaAs substrate.
Using the IRAM 30m millimeter radio telescope we mapped the line emission of the J=1-0 and J=2-1 transitions of 12C0, 13C0, and C180 in the nuclear region of the spiral galaxy IC342. This study demonstrates the value of multi line studies to investigate the neutral interstellar medium in extragalactic sources. Our observations as well as calculations of simple models of CO excitation and radiative transport show that the molecular gas in the nucleus is warm and that physical conditions vary with position in the galaxy. The molecular gas in the central kiloparsec of IC342 has a kinetic temperature of at least 30K and a molecular hydrogen density of about 3xl03 cm”3. At distances more than 500pc north and south of the center the kinetic temperature is significantly less (≥13K). About 500 pc north east of the center we find evidence for optically thin CO emission originating in a component of warm gas with a temperature of at least 40 K. Our model calculations result in conversion factors between the H2 column density and the 12CO (1-0) line intensity close to the value of 3–4×1020 cm-2/K km s-1 derived for molecular clouds in the Galaxy. The molecular mass contained in the central two kpc of IC342 is of the order of 2×108 M⊙.
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