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The Emergence of the American University Abroad
This dissertation explores the relations of independent American universities abroad to one another and to American higher education through a mixed-method comparative case study of three eras (1919-1945; 1946-1990; 1991-2017). Applying insights from the study of organizations and social movements, it investigates 1) the formation, evolution, and eventual maturation of an organizational field of American universities abroad; and 2) the strategies field actors utilize to align frames about American universities abroad with values of potential supporters in the United States. The study employs both qualitative and quantitative methods to analyze data that come from archives, news media, institutional websites, interviews, and an original database. Findings have implications for study of international higher education, American higher education, and American foreign relations. I argue that over the course of a century, the American university abroad has emerged as a distinct institution and structural feature of American higher education. Episodic cooperation among various American universities abroad has served to organize the field to the extent that its “rules” eventually became institutionalized. Instances of continuity and change in the field’s rules are often the result of pressures emanating from U.S. higher education and foreign policies. Meanwhile, the field of American universities abroad, representing the frontier of American higher education, has continually enlarged the latter’s boundaries with each successive period of global expansion
Immune cell proportions correlate with clinicogenomic features and ex vivo drug responses in acute myeloid leukemia
IntroductionThe implementation of small-molecule and immunotherapies in acute myeloid leukemia (AML) has been challenging due to genetic and epigenetic variability amongst patients. There are many potential mechanisms by which immune cells could influence small-molecule or immunotherapy responses, yet, this area remains understudied.MethodsHere we performed cell type enrichment analysis from over 560 AML patient bone marrow and peripheral blood samples from the Beat AML dataset to describe the functional immune landscape of AML.ResultsWe identify multiple cell types that significantly correlate with AML clinical and genetic features, and we also observe significant correlations of immune cell proportions with ex vivo small-molecule and immunotherapy responses. Additionally, we generated a signature of terminally exhausted T cells (Tex) and identified AML with high monocytic proportions as strongly correlating with increased proportions of these immunosuppressive T cells.DiscussionOur work, which is accessible through a new “Cell Type” module in our visualization platform (Vizome; http://vizome.org/), can be leveraged to investigate potential contributions of different immune cells on many facets of the biology of AML
Real-space imaging of polar and elastic nano-textures in thin films via inversion of diffraction data
Exploiting the emerging nanoscale periodicities in epitaxial, single-crystal
thin films is an exciting direction in quantum materials science: confinement
and periodic distortions induce novel properties. The structural motifs of
interest are ferroelastic, ferroelectric, multiferroic, and, more recently,
topologically protected magnetization and polarization textures. A critical
step towards heterostructure engineering is understanding their nanoscale
structure, best achieved through real-space imaging. X-ray Bragg coherent
diffractive imaging visualizes sub-picometer crystalline displacements with
tens of nanometers spatial resolution. Yet, it is limited to objects spatially
confined in all three dimensions and requires highly coherent, laser-like
x-rays. Here we lift the confinement restriction by developing real-space
imaging of periodic lattice distortions: we combine an iterative phase
retrieval algorithm with unsupervised machine learning to invert the diffuse
scattering in conventional x-ray reciprocal-space mapping into real-space
images of polar and elastic textures in thin epitaxial films. We first
demonstrate our imaging in PbTiO3/SrTiO3 superlattices to be consistent with
published phase-field model calculations. We then visualize strain-induced
ferroelastic domains emerging during the metal-insulator transition in Ca2RuO4
thin films. Instead of homogeneously transforming into a low-temperature
structure (like in bulk), the strained Mott insulator splits into nanodomains
with alternating lattice constants, as confirmed by cryogenic scanning
transmission electron microscopy. Our study reveals the type, size,
orientation, and crystal displacement field of the nano-textures. The
non-destructive imaging of textures promises to improve models for their
dynamics and enable advances in quantum materials and microelectronics
The Multi-Object, Fiber-Fed Spectrographs for SDSS and the Baryon Oscillation Spectroscopic Survey
We present the design and performance of the multi-object fiber spectrographs
for the Sloan Digital Sky Survey (SDSS) and their upgrade for the Baryon
Oscillation Spectroscopic Survey (BOSS). Originally commissioned in Fall 1999
on the 2.5-m aperture Sloan Telescope at Apache Point Observatory, the
spectrographs produced more than 1.5 million spectra for the SDSS and SDSS-II
surveys, enabling a wide variety of Galactic and extra-galactic science
including the first observation of baryon acoustic oscillations in 2005. The
spectrographs were upgraded in 2009 and are currently in use for BOSS, the
flagship survey of the third-generation SDSS-III project. BOSS will measure
redshifts of 1.35 million massive galaxies to redshift 0.7 and Lyman-alpha
absorption of 160,000 high redshift quasars over 10,000 square degrees of sky,
making percent level measurements of the absolute cosmic distance scale of the
Universe and placing tight constraints on the equation of state of dark energy.
The twin multi-object fiber spectrographs utilize a simple optical layout
with reflective collimators, gratings, all-refractive cameras, and
state-of-the-art CCD detectors to produce hundreds of spectra simultaneously in
two channels over a bandpass covering the near ultraviolet to the near
infrared, with a resolving power R = \lambda/FWHM ~ 2000. Building on proven
heritage, the spectrographs were upgraded for BOSS with volume-phase
holographic gratings and modern CCD detectors, improving the peak throughput by
nearly a factor of two, extending the bandpass to cover 360 < \lambda < 1000
nm, and increasing the number of fibers from 640 to 1000 per exposure. In this
paper we describe the original SDSS spectrograph design and the upgrades
implemented for BOSS, and document the predicted and measured performances.Comment: 43 pages, 42 figures, revised according to referee report and
accepted by AJ. Provides background for the instrument responsible for SDSS
and BOSS spectra. 4th in a series of survey technical papers released in
Summer 2012, including arXiv:1207.7137 (DR9), arXiv:1207.7326 (Spectral
Classification), and arXiv:1208.0022 (BOSS Overview
HIP 67506 C: MagAO-X Confirmation of a New Low-Mass Stellar Companion to HIP 67506 A
We report the confirmation of HIP 67506 C, a new stellar companion to HIP
67506 A. We previously reported a candidate signal at 2/D (240~mas) in
L in MagAO/Clio imaging using the binary differential imaging
technique. Several additional indirect signals showed that the candidate signal
merited follow-up: significant astrometric acceleration in Gaia DR3,
Hipparcos-Gaia proper motion anomaly, and overluminosity compared to single
main sequence stars. We confirmed the companion, HIP 67506 C, at 0.1" with
MagAO-X in April, 2022. We characterized HIP 67506 C MagAO-X photometry and
astrometry, and estimated spectral type K7-M2; we also re-evaluated HIP 67506 A
in light of the close companion. Additionally we show that a previously
identified 9" companion, HIP 67506 B, is a much further distant unassociated
background star. We also discuss the utility of indirect signposts in
identifying small inner working angle candidate companions.Comment: 10 pages, 9 figures, 4 tables, accepted to MNRA
The Ninth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the SDSS-III Baryon Oscillation Spectroscopic Survey
The Sloan Digital Sky Survey III (SDSS-III) presents the first spectroscopic
data from the Baryon Oscillation Spectroscopic Survey (BOSS). This ninth data
release (DR9) of the SDSS project includes 535,995 new galaxy spectra (median
z=0.52), 102,100 new quasar spectra (median z=2.32), and 90,897 new stellar
spectra, along with the data presented in previous data releases. These spectra
were obtained with the new BOSS spectrograph and were taken between 2009
December and 2011 July. In addition, the stellar parameters pipeline, which
determines radial velocities, surface temperatures, surface gravities, and
metallicities of stars, has been updated and refined with improvements in
temperature estimates for stars with T_eff<5000 K and in metallicity estimates
for stars with [Fe/H]>-0.5. DR9 includes new stellar parameters for all stars
presented in DR8, including stars from SDSS-I and II, as well as those observed
as part of the SDSS-III Sloan Extension for Galactic Understanding and
Exploration-2 (SEGUE-2).
The astrometry error introduced in the DR8 imaging catalogs has been
corrected in the DR9 data products. The next data release for SDSS-III will be
in Summer 2013, which will present the first data from the Apache Point
Observatory Galactic Evolution Experiment (APOGEE) along with another year of
data from BOSS, followed by the final SDSS-III data release in December 2014.Comment: 9 figures; 2 tables. Submitted to ApJS. DR9 is available at
http://www.sdss3.org/dr
The Eighth Data Release of the Sloan Digital Sky Survey: First Data from SDSS-III
The Sloan Digital Sky Survey (SDSS) started a new phase in August 2008, with
new instrumentation and new surveys focused on Galactic structure and chemical
evolution, measurements of the baryon oscillation feature in the clustering of
galaxies and the quasar Ly alpha forest, and a radial velocity search for
planets around ~8000 stars. This paper describes the first data release of
SDSS-III (and the eighth counting from the beginning of the SDSS). The release
includes five-band imaging of roughly 5200 deg^2 in the Southern Galactic Cap,
bringing the total footprint of the SDSS imaging to 14,555 deg^2, or over a
third of the Celestial Sphere. All the imaging data have been reprocessed with
an improved sky-subtraction algorithm and a final, self-consistent photometric
recalibration and flat-field determination. This release also includes all data
from the second phase of the Sloan Extension for Galactic Understanding and
Evolution (SEGUE-2), consisting of spectroscopy of approximately 118,000 stars
at both high and low Galactic latitudes. All the more than half a million
stellar spectra obtained with the SDSS spectrograph have been reprocessed
through an improved stellar parameters pipeline, which has better determination
of metallicity for high metallicity stars.Comment: Astrophysical Journal Supplements, in press (minor updates from
submitted version
Authenticity and place attachment of major visitor attractions
This paper aims to explore the relationships between place attachment and perceived authenticity of major visitor attractions. The empirical study was conducted with a sample of international tourists to major visitor attractions in two capital cities, Helsinki, Finland and Jerusalem, Israel. The results indicate a positive correlation between place attachment and authenticity. Major visitor attractions located in places with considerable heritage experience value are considered more authentic, and that authenticity of visitor attractions is influenced by place attachment moderated by iconicity and heritage value of the destination region. These findings provide insight to the ways tourists perceive authenticity of visitor attractions and highlight the importance of the heritage value of tourism destinations for strategic planning and marketing purposes
The state of the Martian climate
60°N was +2.0°C, relative to the 1981–2010 average value (Fig. 5.1). This marks a new high for the record. The average annual surface air temperature (SAT) anomaly for 2016 for land stations north of starting in 1900, and is a significant increase over the previous highest value of +1.2°C, which was observed in 2007, 2011, and 2015. Average global annual temperatures also showed record values in 2015 and 2016. Currently, the Arctic is warming at more than twice the rate of lower latitudes
The Baryon Oscillation Spectroscopic Survey of SDSS-III
The Baryon Oscillation Spectroscopic Survey (BOSS) is designed to measure the
scale of baryon acoustic oscillations (BAO) in the clustering of matter over a
larger volume than the combined efforts of all previous spectroscopic surveys
of large scale structure. BOSS uses 1.5 million luminous galaxies as faint as
i=19.9 over 10,000 square degrees to measure BAO to redshifts z<0.7.
Observations of neutral hydrogen in the Lyman alpha forest in more than 150,000
quasar spectra (g<22) will constrain BAO over the redshift range 2.15<z<3.5.
Early results from BOSS include the first detection of the large-scale
three-dimensional clustering of the Lyman alpha forest and a strong detection
from the Data Release 9 data set of the BAO in the clustering of massive
galaxies at an effective redshift z = 0.57. We project that BOSS will yield
measurements of the angular diameter distance D_A to an accuracy of 1.0% at
redshifts z=0.3 and z=0.57 and measurements of H(z) to 1.8% and 1.7% at the
same redshifts. Forecasts for Lyman alpha forest constraints predict a
measurement of an overall dilation factor that scales the highly degenerate
D_A(z) and H^{-1}(z) parameters to an accuracy of 1.9% at z~2.5 when the survey
is complete. Here, we provide an overview of the selection of spectroscopic
targets, planning of observations, and analysis of data and data quality of
BOSS.Comment: 49 pages, 16 figures, accepted by A
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