1,782 research outputs found
A Study of the Implementation of the Free, Potable Water Subsection of the Federal Healthy, Hunger-Free Kids Act
The Association of School and Curriculum Development (ASCD), one of the world’s largest education profession organizations and the Centers for Disease Control and Prevention called for a “greater alignment between education and health to improve each child’s cognitive, physical, social and emotional development” (ASCD, 2014, p. 6). Lack of attention to the factors impacting learning can prevent students from reaching their full academic potential because education practitioners are failing to meet their students’ non-instructional needs (ASCD, n.d.). Nothing is more basic than water. Repeated studies have identified hydration as an important factor in learning (Bar-David, Urkin, & Kozminsky, 2005; Edmonds & Burford, 2009; Edmonds & Jeffes, 2009); yet according to Kenney, Gortmaker, and Cohen (2016), “access to clean, functioning free drinking water sources in schools may be limited, and compliance with state and federal policies to establish free drinking water access is low in many schools” (p. 28). Despite the mandate stating the provisions of the federal Healthy, Hunger-Free Kids Act of 2010 (HHFKA; United States Government Publishing Office, 2010), student access to clean drinking water remains limited in schools (Cradock, Wilking, Olliges, & Gortmaker, 2012; Jones, 2016; Kenney et al., 2016). Lack of or poor access to water could result in students not consuming enough to meet their daily needs (Patel & Hampton, 2011). This could yield a negative impact on student achievement (Bar-David et al., 2005; Fuchs, Luhrmann, & Simpson, 2016). The purpose of this cross-site case study was to examine the degree to which schools in a southeastern state school district are implementing the free, potable water subsection of HHFKA. Using a purposive sample, the researcher observed school food service practices in three middle schools and interviewed school and district food service managers. Constant-comparative analysis of interview transcripts and field notes (Glaser & Strauss, 1967) demonstrated wide variance of both knowledge and practice across sites and among interviewed participants. Implications for policymakers and practitioners include greater training of child nutrition professionals, school leaders, and classroom teachers
Detection of Circular Polarization in M81*
We report the detection of circular polarization in the compact radio jet of
the nearby spiral galaxy M81 (M81*). The observations were made with the Very
Large Array at 4.8 and 8.4 GHz and circular polarization was detected at both
frequencies. We estimate a value of at 8.4 GHz and
at 4.8 GHz for the fractional circular
polarization. The errors are separated into statistical and systematic terms.
The spectrum of the circular polarization is possibly inverted which would be
unusual for AGN. We also detected no linear polarization in M81* at a level of
0.1% implying that the source has a very high circular-to-linear polarization
ratio as found so far only in Sgr A*, the central radio source in our Galaxy.
This further supports the idea that M81* is a scaled-up version of Sgr A* and
suggests that the polarization properties are intrinsic to the two sources and
are not caused by a foreground screen in the Galaxy.Comment: 9 pages, 1 figure, accepted for publication in ApJ Letter
Bread: a consumer survey of Christchurch households
This study is the third in a series of AERU
Research Reports presenting results of Consumer Surveys
for various agricultural and horticultural products.
In this study bread is the product under investigation
and Christchurch was the location for the survey.
The objective of the present research was to present
information on consumer purchasing and consumption
patterns and the factors affecting these patterns. The
results presented are particularly timely, as the New
Zealand Association of Bakers is at present considering a
nationwide promotion campaign for bread
ESIM_DSN Web-Enabled Distributed Simulation Network
In this paper, the eSim(sup DSN) approach to achieve distributed simulation capability using the Internet is presented. With this approach a complete simulation can be assembled from component subsystems that run on different computers. The subsystems interact with each other via the Internet The distributed simulation uses a hub-and-spoke type network topology. It provides the ability to dynamically link simulation subsystem models to different computers as well as the ability to assign a particular model to each computer. A proof-of-concept demonstrator is also presented. The eSim(sup DSN) demonstrator can be accessed at http://www.jsc.draper.com/esim which hosts various examples of Web enabled simulations
Disc formation in turbulent massive cores: Circumventing the magnetic braking catastrophe
We present collapse simulations of 100 M_{\sun}, turbulent cloud cores
threaded by a strong magnetic field. During the initial collapse phase
filaments are generated which fragment quickly and form several protostars.
Around these protostars Keplerian discs with typical sizes of up to 100 AU
build up in contrast to previous simulations neglecting turbulence. We examine
three mechanisms potentially responsible for lowering the magnetic braking
efficiency and therefore allowing for the formation of Keplerian discs.
Analysing the condensations in which the discs form, we show that the build-up
of Keplerian discs is neither caused by magnetic flux loss due to turbulent
reconnection nor by the misalignment of the magnetic field and the angular
momentum. It is rather a consequence of the turbulent surroundings of the disc
which exhibit no coherent rotation structure while strong local shear flows
carry large amounts of angular momentum. We suggest that the "magnetic braking
catastrophe", i.e. the formation of sub-Keplerian discs only, is an artefact of
the idealised non-turbulent initial conditions and that turbulence provides a
natural mechanism to circumvent this problem.Comment: 6 pages, 5 figures, accepted by MNRAS Letters, updated to final
versio
Magnetic Braking and Protostellar Disk Formation: Ambipolar Diffusion
It is established that the formation of rotationally supported disks during
the main accretion phase of star formation is suppressed by a moderately strong
magnetic field in the ideal MHD limit. Non-ideal MHD effects are expected to
weaken the magnetic braking, perhaps allowing the disk to reappear. We
concentrate on one such effect, ambipolar diffusion, which enables the field
lines to slip relative to the bulk neutral matter. We find that the slippage
does not sufficiently weaken the braking to allow rotationally supported disks
to form for realistic levels of cloud magnetization and cosmic ray ionization
rate; in some cases, the magnetic braking is even enhanced. Only in dense cores
with both exceptionally weak fields and unreasonably low ionization rate do
such disks start to form in our simulations. We conclude that additional
processes, such as Ohmic dissipation or Hall effect, are needed to enable disk
formation. Alternatively, the disk may form at late times when the massive
envelope that anchors the magnetic brake is dissipated, perhaps by a
protostellar wind.Comment: 16 pages, 4 figure
The water cycle and regolith-atmosphere interaction at Gale crater, Mars
We perform mesoscale simulations of the water cycle in a region around Gale crater, including the diffusion of water vapour in and out of the regolith, and compare our results with measurements from the REMS instrument on board the Curiosity rover. Simulations are performed at three times of year, and show that diffusion in and out of the regolith and adsorption/desorption needs to be taken into account in order to match the diurnal variation of relative humidity measured by REMS. During the evening and night, local downslope flows transport water vapour down the walls of Gale crater. When including regolith-atmosphere interaction, the amount of vapour reaching the crater floor is reduced (by factors of 2–3 depending on season) due to vapour diffusing into the regolith along the crater walls. The transport of vapour into Gale crater is also affected by the regional katabatic flow over the dichotomy boundary, with the largest flux of vapour into the regolith initially occurring on the northern crater wall, and moving to the southern wall by early morning. Upslope winds during the day transport vapour desorbing and mixing out of the regolith up crater walls, where it can then be transported a few hundred metres into the atmosphere at convergence boundaries. Regolith-atmosphere interaction limits the formation of surface ice by reducing water vapour abundances in the lower atmosphere, though in some seasons ice can still form in the early morning on eastern crater walls. Subsurface ice amounts are small in all seasons, with ice only existing in the upper few millimetres of regolith during the night. The results at Gale crater are representative of the behaviour at other craters in the mesoscale domain
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Using Digital Human Modeling to Evaluate and Improve Car Pillar Design: A Proof of Concept and Design of Experiments
Considering human factors in early engineering design stages can improve expensive late stage processes, facilitate user safety, improve product quality and help reduce the need for physical prototyping. Currently, car pillar design (the vertical pillars between windows which connect the roof and car body) provide safety for the passengers in case of a rollover accident. However, these pillars are known to cause accidents because of the vision they obstruct or limit. Literature suggests solutions to this problem by changing the position, geometry and using cameras for an augmented display but these can be expensive, not eliminate the obstruction zone or may require extensive physical prototyping. This research suggests a methodology to analyze and improve vision obstruction through by integrating Computer Aided Design Models (CAD) and Jack Digital Human Modeling (DHM) Software. This research then provides greater evidence through a Design of Experiments to compare different car pillar designs for percent area visible. The results conclude that this is a valuable method to test the amount of vision be obstructed by the pillars. Additionally, the research concludes that provide cuts within the car pillar geometry can provide increased visibility. The results include; four car models, four traffic scenes, six driver anthropometries, four pedestrian anthropometries, percent area of vision obstruction values, generalized Finite Element Analysis (FEA) of pillar designs and statistical models and analyses to prove significance of the car pillar improvements
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