3,045 research outputs found
Goal-neglect links Stroop interference with working memory capacity
Relationships between Stroop interference and working memory capacity may reflect individual differences in resolving conflict, susceptibility to goal neglect, or both of these factors. We compared relationships between working memory capacity and three Stroop tasks: a classic, printed color-word Stroop task, a cross-modal Stroop, and a new version of cross-modal Stroop with a concurrent auditory monitoring component. Each of these tasks showed evidence of interference between the semantic meaning of the color word and the to-be-named color, suggesting these tasks each require resolution of interference. However, only Stroop interference in the print-based task with high proportions of congruent trials correlated significantly with working memory capacity. This evidence suggests that the relationships observed between Stroop interference and working memory capacity are primarily driven by individual differences in the propensity to actively maintain a goal. (C) 2012 Elsevier B.V. All rights reserved
Exoplanet Characterization by Proxy: a Transiting 2.15 R_Earth Planet Near the Habitable Zone of the Late K dwarf Kepler-61
We present the validation and characterization of Kepler-61b: a 2.15 R_Earth
planet orbiting near the inner edge of the habitable zone of a low-mass star.
Our characterization of the host star Kepler-61 is based upon a comparison with
the set of spectroscopically similar stars with directly-measured radii and
temperatures. We apply a stellar prior drawn from the weighted mean of these
properties, in tandem with the Kepler photometry, to infer a planetary radius
for Kepler-61b of 2.15+/-0.13 R_Earth and an equilibrium temperature of
273+/-13 K (given its period of 59.87756+/-0.00020 days and assuming a
planetary albedo of 0.3). The technique of leveraging the physical properties
of nearby "proxy" stars allows for an independent check on stellar
characterization via the traditional measurements with stellar spectra and
evolutionary models. In this case, such a check had implications for the
putative habitability of Kepler-61b: the planet is 10% warmer and larger than
inferred from K-band spectral characterization. From the Kepler photometry, we
estimate a stellar rotation period of 36 days, which implies a stellar age of
>1 Gyr. We summarize the evidence for the planetary nature of the Kepler-61
transit signal, which we conclude is 30,000 times more likely to be due to a
planet than a blend scenario. Finally, we discuss possible compositions for
Kepler-61b with a comparison to theoretical models as well as to known
exoplanets with similar radii and dynamically measured masses.Comment: 23 pages, 12 figures. Accepted for publication in Ap
Cognitive performance among carriers of pathogenic copy number variants: analysis of 152,000 UK Biobank subjects
Background The UK Biobank is a unique resource for biomedical research, with extensive phenotypic and genetic data on half a million adults from the general population. We aimed to examine the effect of neurodevelopmental copy number variants (CNVs) on the cognitive performance of participants. Methods We used Affymetrix Power Tools and PennCNV-Affy software to analyze Affymetrix microarrays of the first 152,728 genotyped individuals. We annotated a list of 93 CNVs and compared their frequencies with control datasets. We analyzed the performance on seven cognitive tests of carriers of 12 CNVs associated with schizophrenia (n = 1087) and of carriers of another 41 neurodevelopmental CNVs (n = 484). Results The frequencies of the 93 CNVs in the Biobank subjects were remarkably similar to those among 26,628 control subjects from other datasets. Carriers of schizophrenia-associated CNVs and of the group of 41 other neurodevelopmental CNVs had impaired performance on the cognitive tests, with nine of 14 comparisons remaining statistically significant after correction for multiple testing. They also had lower educational and occupational attainment (p values between 10−7 and 10−18). The deficits in cognitive performance were modest (Z score reductions between 0.01 and 0.51), compared with individuals with schizophrenia in the Biobank (Z score reductions between 0.35 and 0.90). Conclusions This is the largest study on the cognitive phenotypes of CNVs to date. Adult carriers of neurodevelopmental CNVs from the general population have significant cognitive deficits. The UK Biobank will allow unprecedented opportunities for analysis of further phenotypic consequences of CNVs
Double Beta Decay, Majorana Neutrinos, and Neutrino Mass
The theoretical and experimental issues relevant to neutrinoless double-beta
decay are reviewed. The impact that a direct observation of this exotic process
would have on elementary particle physics, nuclear physics, astrophysics and
cosmology is profound. Now that neutrinos are known to have mass and
experiments are becoming more sensitive, even the non-observation of
neutrinoless double-beta decay will be useful. If the process is actually
observed, we will immediately learn much about the neutrino. The status and
discovery potential of proposed experiments are reviewed in this context, with
significant emphasis on proposals favored by recent panel reviews. The
importance of and challenges in the calculation of nuclear matrix elements that
govern the decay are considered in detail. The increasing sensitivity of
experiments and improvements in nuclear theory make the future exciting for
this field at the interface of nuclear and particle physics.Comment: invited submission to Reviews of Modern Physics, higher resolution
figures available upon request from authors, Version 2 has fixed typos and
some changes after referee report
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