4,164 research outputs found
Supporting the Literacy Development of Striving Readers through Competing Theoretical Perspectives
Abstract
In this paper, we present educators with the theoretical underpinnings of competing pedagogical approaches to literacy instruction. Given the recent push by many states to universally screen students in the early grades for dyslexia and institute phonics-only standards, we seek to reiterate the importance of a balanced approach. Our purpose is to explain how two contrasting orientations regarding the reading process can together form a framework for providing the best literacy education possible for all students, especially striving readers. We explore both the cognitive information-processing and constructivist perspectives and examine prominent models and theories that inform each approach. Recent research showcasing effective instructional strategies that have emerged from both perspectives is presented, and practical ways that both perspectives find expression in effective classroom practice, including meaningful use of technology, are also delineated. Last, we provide explicit case studies illustrating what literacy support looks like when competing information-processing and constructivist perspectives are blended and how teachers can practically utilize dual approaches to support their most vulnerable students. We join our voices with those of other scholars who call on educators to embrace a holistic, balanced approach to literacy instruction that is informed by various perspectives in their effort to reach striving readers.
Keywords: balanced literacy, effective literacy instruction, striving reader
Exploring the quality of life at the end of life (QUAL-E) instrument with Australian palliative care hospital patients: hurdles and directions
The provision of care that enhances the quality of life at the end of life is a fundamental goal of palliative care services. This pilot study explored the application of the Quality of Life at the End of Life (QUAL-E) instrument in a sample of 52 patients who were hospitalized in two metropolitan Western Australian hospitals. Participants were given the option to complete the QUAL-E either as a self-report (n = 9, 17.3 percent) or, aided by a research assistant, as a structured interview (n = 43, 82.7 percent). The instrument demonstrated patient acceptability and face validity, particularly when it was administered with the assistance of a research assistant. Despite having difficulty with some questions, patients expressed their appreciation at being given the opportunity to contribute to the research and to reflect upon and give voice to their thoughts and feelings. Health practitioners indicated that the instrument could be a valuable tool for holistic assessment and service evaluation. We suggest that minor changes be made to the QUAL-E before it is used further in an Australian context; we also recommend that this instrument be tested in other settings and populations
Testing of the on-board attitude determination and control algorithms for SAMPEX
Algorithms for on-board attitude determination and control of the Solar, Anomalous, and Magnetospheric Particle Explorer (SAMPEX) have been expanded to include a constant gain Kalman filter for the spacecraft angular momentum, pulse width modulation for the reaction wheel command, an algorithm to avoid pointing the Heavy Ion Large Telescope (HILT) instrument boresight along the spacecraft velocity vector, and the addition of digital sun sensor (DSS) failure detection logic. These improved algorithms were tested in a closed-loop environment for three orbit geometries, one with the sun perpendicular to the orbit plane, and two with the sun near the orbit plane - at Autumnal Equinox and at Winter Solstice. The closed-loop simulator was enhanced and used as a truth model for the control systems' performance evaluation and sensor/actuator contingency analysis. The simulations were performed on a VAX 8830 using a prototype version of the on-board software
Determination of the size, mass, and density of "exomoons" from photometric transit timing variations
Precise photometric measurements of the upcoming space missions allow the
size, mass, and density of satellites of exoplanets to be determined. Here we
present such an analysis using the photometric transit timing variation
(). We examined the light curve effects of both the transiting planet
and its satellite. We define the photometric central time of the transit that
is equivalent to the transit of a fixed photocenter. This point orbits the
barycenter, and leads to the photometric transit timing variations. The exact
value of depends on the ratio of the density, the mass, and the size of
the satellite and the planet. Since two of those parameters are independent, a
reliable estimation of the density ratio leads to an estimation of the size and
the mass of the exomoon. Upper estimations of the parameters are possible in
the case when an upper limit of is known. In case the density ratio
cannot be estimated reliably, we propose an approximation with assuming equal
densities. The presented photocenter analysis predicts the size of the
satellite better than the mass. We simulated transits of the Earth-Moon system
in front of the Sun. The estimated size and mass of the Moon are 0.020
Earth-mass and 0.274 Earth-size if equal densities are assumed. This result is
comparable to the real values within a factor of 2. If we include the real
density ratio (about 0.6), the results are 0.010 Earth-Mass and 0.253
Earth-size, which agree with the real values within 20%.Comment: 6 pages, 5 figures, to appear in Astronomy and Astrophysic
Unraveling the Helix Nebula: Its Structure and Knots
Through HST imaging of the inner part of the main-ring of the Helix Nebula
together with CTIO 4-m images of the fainter outer parts, we have an
unprecedented-quality view of the nearest bright planetary nebula. These images
have allowed determination that the main-ring of the nebula is composed of an
inner-disk of about 499\arcsec diameter (0.52 pc) surrounded by an outer-ring
(in reality a torus) of 742\arcsec diameter (0.77 pc) whose plane is highly
inclined to the plane of the disk. This outer-ring is surrounded by an
outermost-ring of 1500\arcsec (1.76 pc) diameter which is flattened on the side
colliding with the ambient interstellar medium. The inner-disk has an extended
distribution of low density gas along its rotational axis of symmetry and the
disk is optically thick to ionizing radiation, as is the outer-ring.
Published radial velocities of the knots provides support for the
two-component structure of the main-ring of the nebula and to the idea that the
knots found there are expanding along with the nebular material from which it
recently originated. There is a change in the morphology of the knots as a
function of the distance from the local ionization front. This supports a
scenario in which the knots are formed in or near the ionization front and are
then sculpted by the stellar radiation from the central star as the ionization
front advances beyond them.Comment: 30 pages, 20 figures, many figures have reduce fidelity for astroph
preprint. Note: URLs in preprint were change
Probing the Human Estrogen Receptor-α Binding Requirements for Phenolic Mono- and Di-Hydroxyl Compounds: A Combined Synthesis, Binding and Docking Study
Various estrogen analogs were synthesized and tested for binding to human ERα using a fluorescence polarization displacement assay. Binding affinity and orientation were also predicted using docking calculations. Docking was able to accurately predict relative binding affinity and orientation for estradiol, but only if a tightly bound water molecule bridging Arg394/Glu353 is present. Di-hydroxyl compounds sometimes bind in two orientations, which are flipped in terms of relative positioning of their hydroxyl groups. Di-hydroxyl compounds were predicted to bind with their aliphatic hydroxyl group interacting with His524 in ERα. One nonsteroid-based dihdroxyl compound was 1000-fold specific for ERβ over ERα, and was also 25-fold specific for agonist ERβ versus antagonist activity. Docking predictions suggest this specificity may be due to interaction of the aliphatic hydroxyl with His475 in the agonist form of ERβ, versus with Thr299 in the antagonist form. But, the presence of this aliphatic hydroxyl is not required in all compounds, since mono-hydroxyl (phenolic) compounds bind ERα with high affinity, via hydroxyl hydrogen bonding interactions with the ERα Arg394/Glu353/water triad, and van der Waals interactions with the rest of the molecule
Coherent Optimal Control of Multiphoton Molecular Excitation
We give a framework for molecular multiphoton excitation process induced by
an optimally designed electric field. The molecule is initially prepared in a
coherent superposition state of two of its eigenfunctions. The relative phase
of the two superposed eigenfunctions has been shown to control the optimally
designed electric field which triggers the multiphoton excitation in the
molecule. This brings forth flexibility in desiging the optimal field in the
laboratory by suitably tuning the molecular phase and hence by choosing the
most favorable interfering routes that the system follows to reach the target.
We follow the quantum fluid dynamical formulation for desiging the electric
field with application to HBr molecule.Comment: 5 figure
A Transiting Planet of a Sun-like Star
A planet transits an 11th magnitude, G1V star in the constellation Corona
Borealis. We designate the planet XO-1b, and the star, XO-1, also known as GSC
02041-01657. XO-1 lacks a trigonometric distance; we estimate it to be 200+-20
pc. Of the ten stars currently known to host extrasolar transiting planets, the
star XO-1 is the most similar to the Sun in its physical characteristics: its
radius is 1.0+-0.08 R_Sun, its mass is 1.0+-0.03 M_Sun, V sini < 3 km/s, and
its metallicity [Fe/H] is 0.015+-0.04. The orbital period of the planet XO-1b
is 3.941534+-0.000027 days, one of the longer ones known. The planetary mass is
0.90+-0.07 M_Jupiter, which is marginally larger than that of other transiting
planets with periods between 3 and 4 days. Both the planetary radius and the
inclination are functions of the spectroscopically determined stellar radius.
If the stellar radius is 1.0+-0.08 R_Sun, then the planetary radius is
1.30+-0.11 R_Jupiter and the inclination of the orbit is 87.7+-1.2 degrees. We
have demonstrated a productive international collaboration between professional
and amateur astronomers that was important to distinguishing this planet from
many other similar candidates.Comment: 31 pages, 9 figures, accepted for part 1 of Ap
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