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Development of an interdisciplinary program in an elementary setting : a case study of integrating curriculum topics with the arts.
This qualitative case study focuses on the development of an interdisciplinary program in a Massachusetts urban elementary school over a fourteen month period as it moved from a teacher-directed approach to a student-directed one. An underlying assumption in this study is that integration of the arts supports learning. The interdisciplinary approach employs collaboration of teachers from different disciplines. The researcher in this study is also the art specialist. This study is a teacher\u27s story viewed through a researcher\u27s lens. One question which intrigued this researcher is: Who should choose the interdisciplinary connections, topics, and related arts projects--teachers or students? The naturalistic methodology of qualitative research utilized in this study included data collected through a researcher\u27s journal, participant observer field notes, formal and informal interviews, researcher-made survey questionnaires, videotapes, and student projects. The study examined three focuses: different approach styles, effect of collaborating teachers\u27 role on the learning environment, and factors affecting students\u27 choices when deciding topics and interdisciplinary connections for projects. One conclusion drawn from data revealed that the development of the program was unique to each collaborating team. Although seven approach styles unfolded, the same style used with some teams developed differently. Factors included prior experiences, comfort level, constant reflection and feedback. Concerns inhibiting development included time to plan and scheduling limitations. The effect of the collaborating teachers\u27 role on the learning environment disclosed both interpersonal and intrapersonal characteristics. Collaborating teachers experienced leader, assistant, co-leader, and facilitator roles. Teachers were flexible and adaptable in each role although, at times, the roles felt uncomfortable. The program\u27s development influenced personal teaching strategies and styles, and fostered companionship among members. One concern to emerge was the learning environment itself. It appeared that the location (classroom or art room) effected the choices and effort students put into their projects. Another conclusion drawn from this study is that students should have a voice in the process of learning. Grade four students favored choices in the decision making process and experiences which involved movement or manipulation of materials. These conclusions support elements of brain-based learning and learning through the arts
Bootstrapping the Coronal Magnetic Field with STEREO: I. Unipolar Potential Field Modeling
We investigate the recently quantified misalignment of between the 3-D geometry of stereoscopically triangulated
coronal loops observed with STEREO/EUVI (in four active regions) and
theoretical (potential or nonlinear force-free) magnetic field models
extrapolated from photospheric magnetograms. We develop an efficient method of
bootstrapping the coronal magnetic field by forward-fitting a parameterized
potential field model to the STEREO-observed loops. The potential field model
consists of a number of unipolar magnetic charges that are parameterized by
decomposing a photospheric magnetogram from MDI. The forward-fitting method
yields a best-fit magnetic field model with a reduced misalignment of
. We evaluate also stereoscopic
measurement errors and find a contribution of , which constrains the residual misalignment to
, which is likely
due to the nonpotentiality of the active regions. The residual misalignment
angle of the potential field due to nonpotentiality is found to
correlate with the soft X-ray flux of the active region, which implies a
relationship between electric currents and plasma heating.Comment: 12 figures, manuscript submitted to ApJ, 2010 Apr 2
Nonlinear force-free field modeling of a solar active region using SDO/HMI and SOLIS/VSM data
We use SDO/HMI and SOLIS/VSM photospheric magnetic field measurements to
model the force-free coronal field above a solar active region, assuming
magnetic forces to dominate. We take measurement uncertainties caused by, e.g.,
noise and the particular inversion technique into account. After searching for
the optimum modeling parameters for the particular data sets, we compare the
resulting nonlinear force-free model fields. We show the degree of agreement of
the coronal field reconstructions from the different data sources by comparing
the relative free energy content, the vertical distribution of the magnetic
pressure and the vertically integrated current density. Though the longitudinal
and transverse magnetic flux measured by the VSM and HMI is clearly different,
we find considerable similarities in the modeled fields. This indicates the
robustness of the algorithm we use to calculate the nonlinear force-free fields
against differences and deficiencies of the photospheric vector maps used as an
input. We also depict how much the absolute values of the total force-free,
virial and the free magnetic energy differ and how the orientation of the
longitudinal and transverse components of the HMI- and VSM-based model volumes
compares to each other.Comment: 9 pages, 5 figure
Structure and Evolution of Giant Cells in Global Models of Solar Convection
The global scales of solar convection are studied through three-dimensional
simulations of compressible convection carried out in spherical shells of
rotating fluid which extend from the base of the convection zone to within 15
Mm of the photosphere. Such modelling at the highest spatial resolution to date
allows study of distinctly turbulent convection, revealing that coherent
downflow structures associated with giant cells continue to play a significant
role in maintaining the strong differential rotation that is achieved. These
giant cells at lower latitudes exhibit prograde propagation relative to the
mean zonal flow, or differential rotation, that they establish, and retrograde
propagation of more isotropic structures with vortical character at mid and
high latitudes. The interstices of the downflow networks often possess strong
and compact cyclonic flows. The evolving giant-cell downflow systems can be
partly masked by the intense smaller scales of convection driven closer to the
surface, yet they are likely to be detectable with the helioseismic probing
that is now becoming available. Indeed, the meandering streams and varying
cellular subsurface flows revealed by helioseismology must be sampling
contributions from the giant cells, yet it is difficult to separate out these
signals from those attributed to the faster horizontal flows of
supergranulation. To aid in such detection, we use our simulations to describe
how the properties of giant cells may be expected to vary with depth, how their
patterns evolve in time, and analyze the statistical features of correlations
within these complex flow fields.Comment: 22 pages, 16 figures (color figures are low res), uses emulateapj.cls
Latex class file, Results shown during a Press release at the AAS meeting in
June 2007. Submitted to Ap
The Influence of Spatial Resolution on Nonlinear Force-Free Modeling
The nonlinear force-free field (NLFFF) model is often used to describe the
solar coronal magnetic field, however a series of earlier studies revealed
difficulties in the numerical solution of the model in application to
photospheric boundary data. We investigate the sensitivity of the modeling to
the spatial resolution of the boundary data, by applying multiple codes that
numerically solve the NLFFF model to a sequence of vector magnetogram data at
different resolutions, prepared from a single Hinode/SOT-SP scan of NOAA Active
Region 10978 on 2007 December 13. We analyze the resulting energies and
relative magnetic helicities, employ a Helmholtz decomposition to characterize
divergence errors, and quantify changes made by the codes to the vector
magnetogram boundary data in order to be compatible with the force-free model.
This study shows that NLFFF modeling results depend quantitatively on the
spatial resolution of the input boundary data, and that using more highly
resolved boundary data yields more self-consistent results. The free energies
of the resulting solutions generally trend higher with increasing resolution,
while relative magnetic helicity values vary significantly between resolutions
for all methods. All methods require changing the horizontal components, and
for some methods also the vertical components, of the vector magnetogram
boundary field in excess of nominal uncertainties in the data. The solutions
produced by the various methods are significantly different at each resolution
level. We continue to recommend verifying agreement between the modeled field
lines and corresponding coronal loop images before any NLFFF model is used in a
scientific setting.Comment: Accepted to ApJ; comments/corrections to this article are welcome via
e-mail, even after publicatio
Persistent neutrophil to lymphocyte ratio >3 during treatment with enzalutamide and clinical outcome in patients with castration-resistant prostate cancer
The baseline value of neutrophil to lymphocyte ratio (NLR) has been found to be prognostic in patients with metastatic castration resistant prostate cancer (CRPC). We evaluated the impact of baseline NLR and its change in patients receiving enzalutamide. We included consecutive metastatic CRPC patients treated with enzalutamide after docetaxel and studies the change of NLR (>3 vs ≤3) after week 4 and 12 weeks. Progression-free survival (PFS), overall survival (OS) and their 95% Confidence Intervals (95% CI) were estimated by the Kaplan-Meier method and compared with the log-rank test. The impact of NLR on PFS and OS was evaluated by Cox regression analyses and on prostate-specific antigen response rates (PSA RR; PSA decline >50%) were evaluated by binary logistic regression. Data collected on 193 patients from 9 centers were evaluated. Median age was 73.1 years (range, 42.8–90.7). The median baseline NLR was 3.2. The median PFS was 3.2 months (95% CI = 2.7–4.2) in patients with baseline NLR >3 and 7.4 months (95% CI = 5.5–9.7) in those with NLR ≤3, p < 0.0001. The median OS was 10.4 months (95% CI = 6.5–14.9) in patients with baseline NLR >3 and 16.9 months (95% CI = 11.2–20.9) in those with baseline NLR ≤3, p < 0.0001. In multivariate analysis, changes in NLR at 4 weeks were significant predictors of both PFS [hazard ratio (HR) 1.24, 95% confidence interval (95% CI) 1.07–1.42, p = 0.003, and OS (HR 1.29, 95% CI 1.10–1.51, p = 0.001. A persistent NLR >3 during treatment with enzalutamide seems to have both prognostic and predictive value in CRPC patients
Inferring Maps of the Sun's Far-side Unsigned Magnetic Flux from Far-side Helioseismic Images using Machine Learning Techniques
Accurate modeling of the Sun's coronal magnetic field and solar wind
structures require inputs of the solar global magnetic field, including both
the near and far sides, but the Sun's far-side magnetic field cannot be
directly observed. However, the Sun's far-side active regions are routinely
monitored by helioseismic imaging methods, which only require continuous
near-side observations. It is therefore both feasible and useful to estimate
the far-side magnetic-flux maps using the far-side helioseismic images despite
their relatively low spatial resolution and large uncertainties. In this work,
we train two machine-learning models to achieve this goal. The first
machine-learning training pairs simultaneous SDO/HMI-observed magnetic-flux
maps and SDO/AIA-observed EUV 304 images, and the resulting model can
convert 304 images into magnetic-flux maps. This model is then applied
on the STEREO/EUVI-observed far-side 304 images, available for about 4.3
years, for the far-side magnetic-flux maps. These EUV-converted magnetic-flux
maps are then paired with simultaneous far-side helioseismic images for a
second machine-learning training, and the resulting model can convert far-side
helioseismic images into magnetic-flux maps. These helioseismically derived
far-side magnetic-flux maps, despite their limitations in spatial resolution
and accuracy, can be routinely available on a daily basis, providing useful
magnetic information on the Sun's far side using only the near-side
observations.Comment: Accepted by Ap
Simultaneous N-Deglycosylation and Digestion of Complex Samples on S-Traps Enables Efficient Glycosite Hypothesis Generation
N-linked glycosylation is an important post-translational modification that is difficult to identify and quantify in traditional bottom-up proteomics experiments. Enzymatic deglycosylation of proteins by peptide:N-glycosidase F (PNGase F) prior to digestion and subsequent mass spectrometry analysis has been shown to improve coverage of various N-linked glycopeptides, but the inclusion of this step may add up to a day to an already lengthy sample preparation process. An efficient way to integrate deglycosylation with bottom-up proteomics would be a valuable contribution to the glycoproteomics field. Here, we demonstrate a proteomics workflow in which deglycosylation and proteolytic digestion of samples occur simultaneously using suspension trapping (S-Trap). This approach adds no time to standard digestion protocols. Applying this sample preparation strategy to a human serum sample, we demonstrate improved identification of potential N-glycosylated peptides in deglycosylated samples compared with non-deglycosylated samples, identifying 156 unique peptides that contain the N-glycosylation motif (asparagine-X-serine/threonine), the deamidation modification characteristic of PNGase F, and an increase in peptide intensity over a control sample. We expect that this rapid sample preparation strategy will assist in the identification and quantification of both known and potential glycoproteins. Data are available via ProteomeXchange with the identifier PXD037921
Coronal Loop Oscillations Observed with AIA - Kink-Mode with Cross-Sectional and Density Oscillations
A detailed analysis of a coronal loop oscillation event is presented, using
data from the Atmospheric Imaging Assembly (AIA) onboard the Solar Dynamics
Observatory (SDO) for the first time. The loop oscillation event occurred on
2010 Oct 16, 19:05-19:35 UT, was triggered by an M2.9 GOES-class flare, located
inside a highly inclined cone of a narrow-angle CME. This oscillation event had
a number of unusual features: (i) Excitation of kink-mode oscillations in
vertical polarization (in the loop plane); (ii) Coupled cross-sectional and
density oscillations with identical periods; (iii) no detectable kink amplitude
damping over the observed duration of four kink-mode periods ( min);
(iv) multi-loop oscillations with slightly () different periods;
and (v) a relatively cool loop temperature of MK. We employ a
novel method of deriving the electron density ratio external and internal to
the oscillating loop from the ratio of Alfv\'enic speeds deduced from the flare
trigger delay and the kink-mode period, i.e.,
. The coupling of the kink mode and
cross-sectional oscillations can be explained as a consequence of the loop
length variation in the vertical polarization mode. We determine the exact
footpoint locations and loop length with stereoscopic triangulation using
STEREO/EUVI-A data. We model the magnetic field in the oscillating loop using
HMI/SDO magnetogram data and a potential field model and find agreement with
the seismological value of the magnetic field, G, within a
factor of two.Comment: ApJ (in press, accepted May 10, 2011
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