5,306 research outputs found
The New Neighbors: A User's Guide to Data on Immigrants in U.S. Communities
Provides a guide for identifying characteristics, contributions, and needs of immigrant populations. Discusses national immigration trends, and addresses public policy questions. Includes a profile of the immigrant population in Providence, Rhode Island
Concert recording 2017-08-21
[Track 1]. Concerto in E♭. I. Allegro [Track 2]. II. Largo [Track 3]. III. Vivace / Johann Baptist Georg Neruda -- [Track 4]. Sonataine pour trompette et piano / Bohuslav Martinů -- [Track 5]. Sonata for trumpet and piano. I. Lento, allegro molto II. Allegretto [Track 6]. III. Allegro con fuoco / Eric Ewazen -- [Track 7]. Nightsongs / Richard Peaslee
WP 2017-377
Working paperSame-sex marriage became legal nationwide in the United States on June 26, 2015. Federal legalization of same-sex marriage expands the pool of individuals potentially eligible for spousal Social Security benefits to the estimated 4 percent of the population that is lesbian, gay, or bisexual. This paper is a foundational step toward better understanding the potential impact of the expansion of marriage rights to same-sex couples on Social Security. We primarily use data from the 2011-2015 American Community Survey to describe the economic circumstances of couple households. Building on this information, we find that same-sex couples tend to have higher household earnings than heterosexual couples, especially male couples. We estimate that same-sex couples have a smaller earnings gap (up to 4 percentage points) compared with heterosexuals. Intrahousehold division of labor explains 58 to 66 percent of the observed smaller earnings gaps in same-sex versus heterosexual couples. Same-sex married couples are less likely than heterosexuals to qualify for spousal SS benefits, but given that they are eligible, males can generally claim higher benefit amounts than heterosexuals (about 7,200 /year). We project spousal benefit claims for same-sex couples 2017 to 2040, using standard demographic methods to estimate the gay and lesbian population by age and sex for this period. Finally, we collect new data that confirm the results obtained from the ACS, and provide insights about subjective expectations about marriage and labor supply prospects for this population. These can be used for future estimations.Social Security Administration, RRC08098401-09, R-UM17-07https://deepblue.lib.umich.edu/bitstream/2027.42/143131/1/wp377.pd
Learning from eXtreme Bandit Feedback
We study the problem of batch learning from bandit feedback in the setting of
extremely large action spaces. Learning from extreme bandit feedback is
ubiquitous in recommendation systems, in which billions of decisions are made
over sets consisting of millions of choices in a single day, yielding massive
observational data. In these large-scale real-world applications, supervised
learning frameworks such as eXtreme Multi-label Classification (XMC) are widely
used despite the fact that they incur significant biases due to the mismatch
between bandit feedback and supervised labels. Such biases can be mitigated by
importance sampling techniques, but these techniques suffer from impractical
variance when dealing with a large number of actions. In this paper, we
introduce a selective importance sampling estimator (sIS) that operates in a
significantly more favorable bias-variance regime. The sIS estimator is
obtained by performing importance sampling on the conditional expectation of
the reward with respect to a small subset of actions for each instance (a form
of Rao-Blackwellization). We employ this estimator in a novel algorithmic
procedure -- named Policy Optimization for eXtreme Models (POXM) -- for
learning from bandit feedback on XMC tasks. In POXM, the selected actions for
the sIS estimator are the top-p actions of the logging policy, where p is
adjusted from the data and is significantly smaller than the size of the action
space. We use a supervised-to-bandit conversion on three XMC datasets to
benchmark our POXM method against three competing methods: BanditNet, a
previously applied partial matching pruning strategy, and a supervised learning
baseline. Whereas BanditNet sometimes improves marginally over the logging
policy, our experiments show that POXM systematically and significantly
improves over all baselines
Small Molecule Recognition of c-Src via the Imatinib-Binding Conformation
SummaryThe cancer drug, Imatinib, is a selective Abl kinase inhibitor that does not inhibit the closely related kinase c-Src. This one drug and its ability to selectively inhibit Abl over c-Src has been a guiding principle in virtually all kinase drug discovery efforts in the last 15 years. A prominent hypothesis explaining the selectivity of Imatinib is that Abl has an intrinsic ability to adopt an inactive conformation (termed DFG-out), whereas c-Src appears to pay a high intrinsic energetic penalty for adopting this conformation, effectively excluding Imatinib from its ATP pocket. This explanation of the difference in binding affinity of Imatinib for Abl versus c-Src makes the striking prediction that it would not be possible to design an inhibitor that binds to the DFG-out conformation of c-Src with high affinity. We report the discovery of a series of such inhibitors. We use structure-activity relationships and X-ray crystallography to confirm our findings. These studies suggest that small molecules are capable of inducing the generally unfavorable DFG-out conformation in c-Src. Structural comparison between c-Src in complex with these inhibitors allows us to speculate on the differential selectivity of Imatinib for c-Src and Abl
A new reference genome assembly for the microcrustacean Daphnia pulex
Comparing genomes of closely related genotypes from populations with distinct demographic histories can help reveal the impact of effective population size on genome evolution. For this purpose, we present a high quality genome assembly of Daphnia pulex (PA42), and compare this with the first sequenced genome of this species (TCO), which was derived from an isolate from a population with >90% reduction in nucleotide diversity. PA42 has numerous similarities to TCO at the gene level, with an average amino acid sequence identity of 98.8 and >60% of orthologous proteins identical. Nonetheless, there is a highly elevated number of genes in the TCO genome annotation, with similar to 7000 excess genes appearing to be false positives. This view is supported by the high GC content, lack of introns, and short length of these suspicious gene annotations. Consistent with the view that reduced effective population size can facilitate the accumulation of slightly deleterious genomic features, we observe more proliferation of transposable elements (TEs) and a higher frequency of gained introns in the TCO genome
ALMA polarimetry measures magnetically aligned dust grains in the torus of NGC 1068
The obscuring structure surrounding active galactic nuclei (AGN) can be
explained as a dust and gas flow cycle that fundamentally connects the AGN with
their host galaxies. This structure is believed to be associated with dusty
winds driven by radiation pressure. However, the role of magnetic fields, which
are invoked in almost all models for accretion onto a supermassive black hole
and outflows, is not thoroughly studied. Here we report the first detection of
polarized thermal emission by means of magnetically aligned dust grains in the
dusty torus of NGC 1068 using ALMA Cycle 4 polarimetric dust continuum
observations (, pc; 348.5 GHz, m). The polarized torus
has an asymmetric variation across the equatorial axis with a peak polarization
of \% and position angle of (B-vector) at
pc east from the core. We compute synthetic polarimetric observations of
magnetically aligned dust grains assuming a toroidal magnetic field and
homogeneous grain alignment. We conclude that the measured 860 m continuum
polarization arises from magnetically aligned dust grains in an optically thin
region of the torus. The asymmetric polarization across the equatorial axis of
the torus arises from 1) an inhomogeneous optical depth, and 2) a variation of
the velocity dispersion, i.e. variation of the magnetic field turbulence at
sub-pc scales, from the eastern to the western region of the torus. These
observations and modeling constrain the torus properties beyond spectral energy
distribution results. This study strongly supports that magnetic fields up to a
few pc contribute to the accretion flow onto the active nuclei.Comment: 19 pages, 11 figures (Accepted for Publication to ApJ
Scalar Top Quark as the Next-to-Lightest Supersymmetric Particle
We study phenomenologically the scenario in which the scalar top quark is
lighter than any other standard supersymmetric partner and also lighter than
the top quark, so that it decays to the gravitino via stop -> W^+ b G. In this
case, scalar top quark events would seem to be very difficult to separate from
top quark pair production. However, we show that, even at a hadron collider, it
is possible to distinguish these two reactions. We show also that the
longitudinal polarization of the final gives insight into the scalar top
and wino/Higgsino mixing parameters.Comment: 18 pages, LaTeX, 7 figures, minor typographical correction
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