1,067 research outputs found
Factors affecting mortality in late stage Parkinson’s Disease
To determine the effect of dysphagia and hospital admissions on mortality in late stage Parkinson’s disease
Trade and Investment in Central and Eastern Europe: A Bibliographic Survey of Current Literature in English
The year 1989 will be remembered as an important year in the histories of the Central and Eastern European countries because of the demise of the Soviet-controlled regimes and the emergence of independent and largely pluralistic political movements. A major catalyst for such radical political change was the decline of the centralized command economies in the Central and Eastern European countries. These so-called Soviet Bloc countries modeled their economic systems after the Soviet Union and, like the Soviet model, these countries found themselves saddled with an increasingly inefficient economic system. When the political systems changed, the new governments immediately took steps to change their economic situation through decentralization, establishing market mechanisms, and privatization. Aware that any improvement required international capital and technology assistance in addition to the development of export markets in the West, they also set out to reshape their foreign trade and investment mechanisms. Their goal was to liberalize foreign trade and open their economies to foreign investment and acquisitions
A Chemical Composition Survey of the Iron-Complex Globular Cluster NGC 6273 (M 19)
Recent observations have shown that a growing number of the most massive
Galactic globular clusters contain multiple populations of stars with different
[Fe/H] and neutron-capture element abundances. NGC 6273 has only recently been
recognized as a member of this "iron-complex" cluster class, and we provide
here a chemical and kinematic analysis of > 300 red giant branch (RGB) and
asymptotic giant branch (AGB) member stars using high resolution spectra
obtained with the Magellan-M2FS and VLT-FLAMES instruments. Multiple lines of
evidence indicate that NGC 6273 possesses an intrinsic metallicity spread that
ranges from about [Fe/H] = -2 to -1 dex, and may include at least three
populations with different [Fe/H] values. The three populations identified here
contain separate first (Na/Al-poor) and second (Na/Al-rich) generation stars,
but a Mg-Al anti-correlation may only be present in stars with [Fe/H] > -1.65.
The strong correlation between [La/Eu] and [Fe/H] suggests that the s-process
must have dominated the heavy element enrichment at higher metallicities. A
small group of stars with low [alpha/Fe] is identified and may have been
accreted from a former surrounding field star population. The cluster's large
abundance variations are coupled with a complex, extended, and multimodal blue
horizontal branch (HB). The HB morphology and chemical abundances suggest that
NGC 6273 may have an origin that is similar to omega Cen and M 54.Comment: Accepted for Publication in The Astrophysical Journal; 50 pages; 18
figures; 8 tables; higher resolution figures are available upon request or in
the published journal articl
Prediction under Latent Subgroup Shifts with High-Dimensional Observations
We introduce a new approach to prediction in graphical models with
latent-shift adaptation, i.e., where source and target environments differ in
the distribution of an unobserved confounding latent variable. Previous work
has shown that as long as "concept" and "proxy" variables with appropriate
dependence are observed in the source environment, the latent-associated
distributional changes can be identified, and target predictions adapted
accurately. However, practical estimation methods do not scale well when the
observations are complex and high-dimensional, even if the confounding latent
is categorical. Here we build upon a recently proposed probabilistic
unsupervised learning framework, the recognition-parametrised model (RPM), to
recover low-dimensional, discrete latents from image observations. Applied to
the problem of latent shifts, our novel form of RPM identifies causal latent
structure in the source environment, and adapts properly to predict in the
target. We demonstrate results in settings where predictor and proxy are
high-dimensional images, a context to which previous methods fail to scale
Unsupervised representation learning with recognition-parametrised probabilistic models
We introduce a new approach to probabilistic unsupervised learning based on
the recognition-parametrised model (RPM): a normalised semi-parametric
hypothesis class for joint distributions over observed and latent variables.
Under the key assumption that observations are conditionally independent given
latents, the RPM combines parametric prior and observation-conditioned latent
distributions with non-parametric observation marginals. This approach leads to
a flexible learnt recognition model capturing latent dependence between
observations, without the need for an explicit, parametric generative model.
The RPM admits exact maximum-likelihood learning for discrete latents, even for
powerful neural-network-based recognition. We develop effective approximations
applicable in the continuous-latent case. Experiments demonstrate the
effectiveness of the RPM on high-dimensional data, learning image
classification from weak indirect supervision; direct image-level latent
Dirichlet allocation; and recognition-parametrised Gaussian process factor
analysis (RP-GPFA) applied to multi-factorial spatiotemporal datasets. The RPM
provides a powerful framework to discover meaningful latent structure
underlying observational data, a function critical to both animal and
artificial intelligence
Unlocking biomarker discovery: Large scale application of aptamer proteomic technology for early detection of lung cancer
Lung cancer is the leading cause of cancer deaths, because ~84% of cases are diagnosed at an advanced stage. Worldwide in 2008, ~1.5 million people were diagnosed and ~1.3 million died – a survival rate unchanged since 1960. However, patients diagnosed at an early stage and have surgery experience an 86% overall 5-year survival. New diagnostics are therefore needed to identify lung cancer at this stage. Here we present the first large scale clinical use of aptamers to discover blood protein biomarkers in disease with our breakthrough proteomic technology. This multi-center case-control study was conducted in archived samples from 1,326 subjects from four independent studies of non-small cell lung cancer (NSCLC) in long-term tobacco-exposed populations. We measured >800 proteins in 15uL of serum, identified 44 candidate biomarkers, and developed a 12-protein panel that distinguished NSCLC from controls with 91% sensitivity and 84% specificity in a training set and 89% sensitivity and 83% specificity in a blinded, independent verification set. Performance was similar for early and late stage NSCLC. This is a significant advance in proteomics in an area of high clinical need
Reproducibility of ambulatory blood pressure changes from the initial values on two different days
OBJECTIVE: We tested the reproducibility of changes in the ambulatory blood pressure (BP) from the initial values, an indicator of BP reactivity and cardiovascular health outcomes, in young, healthy adults. METHOD: The subjects wore an ambulatory BP monitor attached by the same investigator at the same time of day until the next morning on two different days (day 1 and day 2) separated by a week. We compared the ambulatory BP change from the initial values at hourly intervals over 24 waking and sleeping hours on days 1 and 2 using linear regression and repeated measures analysis of covariance. RESULTS: The subjects comprised 88 men and 57 women (mean age±SE 22.4±0.3 years) with normal BP (118.3±0.9/69.7±0.6 mmHg). For the total sample, the correlation between the ambulatory BP change on day 1 vs. day 2 over 24, waking, and sleeping hours ranged from 0.37-0.61; among women, the correlation was 0.38-0.71, and among men, it was 0.24-0.52. Among women, the ambulatory systolic/diastolic BP change was greater by 3.1±1.0/2.4±0.8 mmHg over 24 hours and by 3.0±1.1/2.4±0.8 mmHg over waking hours on day 1 than on day 2. The diastolic ambulatory BP change during sleeping hours was greater by 2.2±0.9 mmHg on day 1 than on day 2, but the systolic ambulatory BP change during sleeping hours on days 1 and 2 did not differ. Among men, the ambulatory BP change on days 1 and 2 did not differ. CONCLUSION: Our primary findings were that the ambulatory BP change from the initial values was moderately reproducible; however, it was more reproducible in men than in women. These results suggest that women, but not men, may experience an alerting reaction to initially wearing the ambulatory BP monitor
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