470 research outputs found
Application of Volcano Plots in Analyses of mRNA Differential Expressions with Microarrays
Volcano plot displays unstandardized signal (e.g. log-fold-change) against
noise-adjusted/standardized signal (e.g. t-statistic or -log10(p-value) from
the t test). We review the basic and an interactive use of the volcano plot,
and its crucial role in understanding the regularized t-statistic. The joint
filtering gene selection criterion based on regularized statistics has a curved
discriminant line in the volcano plot, as compared to the two perpendicular
lines for the "double filtering" criterion. This review attempts to provide an
unifying framework for discussions on alternative measures of differential
expression, improved methods for estimating variance, and visual display of a
microarray analysis result. We also discuss the possibility to apply volcano
plots to other fields beyond microarray.Comment: 8 figure
Evolution of dopant-induced helium nanoplasmas
Two-component nanoplasmas generated by strong-field ionization of doped
helium nanodroplets are studied in a pump-probe experiment using few-cycle
laser pulses in combination with molecular dynamics simulations. High yields of
helium ions and a pronounced, droplet size-dependent resonance structure in the
pump-probe transients reveal the evolution of the dopant-induced helium
nanoplasma. The pump-probe dynamics is interpreted in terms of strong inner
ionization by the pump pulse and resonant heating by the probe pulse which
controls the final charge states detected via the frustration of electron-ion
recombination
Signal of Quark Deconfinement in the Timing Structure of Pulsar Spin-Down
The conversion of nuclear matter to quark matter in the core of a rotating
neutron star alters its moment of inertia. Hence the epoch over which
conversion takes place will be signaled in the spin-down "signal_prl.tex" 581
lines, 22203 characters characteristics of pulsars. We find that an observable
called the braking index should be easily measurable during the transition
epoch and can have a value far removed (by orders of magnitude) from the
canonical value of three expected for magnetic dipole radiation, and may have
either sign. The duration of the transition epoch is governed by the slow loss
of angular momentum to radiation and is further prolonged by the reduction in
the moment of inertia caused by the phase change which can even introduce an
era of spin-up. We estimate that about one in a hundred pulsars may be passing
through this phase. The phenomenon is analogous to ``bachbending'' observed in
the moment of inertia of rotating nuclei observed in the 1970's, which also
signaled a change in internal structure with changing spin.Comment: 5 pages, 4 figures, Revtex. (May 12, 1997, submitted to PRL
Psychosocial Screening in Disorders/Differences of Sex Development: Psychometric Evaluation of the Psychosocial Assessment Tool
© 2019 S. Karger AG, Basel. Background/Aims: Utilization of a psychosocial screener to identify families affected by a disorder/difference of sex development (DSD) and at risk for adjustment challenges may facilitate efficient use of team resources to optimize care. The Psychosocial Assessment Tool (PAT) has been used in other pediatric conditions. The current study explored the reliability and validity of the PAT (modified for use within the DSD population; PAT-DSD). Methods: Participants were 197 families enrolled in the DSD-Translational Research Network (DSD-TRN) who completed a PAT-DSD during a DSD clinic visit. Psychosocial data were extracted from the DSD-TRN clinical registry. Internal reliability of the PAT-DSD was tested using the Kuder-Richardson-20 coefficient. Validity was examined by exploring the correlation of the PAT-DSD with other measures of caregiver distress and child emotional-behavioral functioning. Results: One-third of families demonstrated psychosocial risk (27.9% Targeted and 6.1% Clinical level of risk). Internal reliability of the PAT-DSD Total score was high (α = 0.86); 4 of 8 subscales met acceptable internal reliability. A priori predicted relationships between the PAT-DSD and other psychosocial measures were supported. The PAT-DSD Total score related to measures of caregiver distress (r = 0.40, p \u3c 0.001) and to both caregiver-reported and patient self-reported behavioral problems (r = 0.61, p \u3c 0.00; r = 0.37, p \u3c 0.05). Conclusions: This study provides evidence for the reliability and validity of the PAT-DSD. Given variability in the internal reliability across subscales, this measure is best used to screen for overall family risk, rather than to assess specific psychosocial concerns
MLP: a MATLAB toolbox for rapid and reliable auditory threshold estimation
In this paper, we present MLP, a MATLAB toolbox enabling auditory
thresholds estimation via the adaptive Maximum Likelihood procedure proposed
by David Green (1990, 1993). This adaptive procedure is particularly appealing for
those psychologists that need to estimate thresholds with a good degree of accuracy
and in a short time. Together with a description of the toolbox, the current text
provides an introduction to the threshold estimation theory and a theoretical
explanation of the maximum likelihood adaptive procedure. MLP comes with a
graphical interface and it is provided with several built-in, classic psychoacoustics
experiments ready to use at a mouse click
Intrinsic gain modulation and adaptive neural coding
In many cases, the computation of a neural system can be reduced to a
receptive field, or a set of linear filters, and a thresholding function, or
gain curve, which determines the firing probability; this is known as a
linear/nonlinear model. In some forms of sensory adaptation, these linear
filters and gain curve adjust very rapidly to changes in the variance of a
randomly varying driving input. An apparently similar but previously unrelated
issue is the observation of gain control by background noise in cortical
neurons: the slope of the firing rate vs current (f-I) curve changes with the
variance of background random input. Here, we show a direct correspondence
between these two observations by relating variance-dependent changes in the
gain of f-I curves to characteristics of the changing empirical
linear/nonlinear model obtained by sampling. In the case that the underlying
system is fixed, we derive relationships relating the change of the gain with
respect to both mean and variance with the receptive fields derived from
reverse correlation on a white noise stimulus. Using two conductance-based
model neurons that display distinct gain modulation properties through a simple
change in parameters, we show that coding properties of both these models
quantitatively satisfy the predicted relationships. Our results describe how
both variance-dependent gain modulation and adaptive neural computation result
from intrinsic nonlinearity.Comment: 24 pages, 4 figures, 1 supporting informatio
Atmospheric neutrino oscillation analysis with sub-leading effects in Super-Kamiokande I, II, and III
We present a search for non-zero theta_{13} and deviations of sin^2
theta_{23} from 0.5 in the oscillations of atmospheric neutrino data from
Super-Kamiokande -I, -II, and -III. No distortions of the neutrino flux
consistent with non-zero theta_{13} are found and both neutrino mass hierarchy
hypotheses are in agreement with the data. The data are best fit at Delta m^2 =
2.1 x 10^-3 eV^2, sin^2 theta_{13} = 0.0, and sin^2 theta_{23} =0.5. In the
normal (inverted) hierarchy theta_{13} and Delta m^2 are constrained at the
one-dimensional 90% C.L. to sin^2 theta_{13} < 0.04 (0.09) and 1.9 (1.7) x
10^-3 < Delta m^2 < 2.6 (2.7) x 10^-3 eV^2. The atmospheric mixing angle is
within 0.407 <= sin^2 theta_{23} <= 0.583 at 90% C.L.Comment: 17 Pages, 14 figures. To be submitted to Phys. Rev. D Minor update to
text after referee comments. Figures modified for better grayscale printing
Search for Matter-Dependent Atmospheric Neutrino Oscillations in Super-Kamiokande
We consider muon neutrino to tau neutrino oscillations in the context of the
Mass Varying Neutrino (MaVaN) model, where the neutrino mass can vary depending
on the electron density along the flight path of the neutrino. Our analysis
assumes a mechanism with dependence only upon the electron density, hence
ordinary matter density, of the medium through which the neutrino travels.
Fully-contained, partially-contained and upward-going muon atmospheric neutrino
data from the Super--Kamiokande detector, taken from the entire SK--I period of
1489 live days, are compared to MaVaN model predictions. We find that, for the
case of 2-flavor oscillations, and for the specific models tested, oscillation
independent of electron density is favored over density dependence. Assuming
maximal mixing, the best-fit case and the density-independent case do not
differ significantly.Comment: 6 pages, 1 figur
Set-valued orthogonal additivity
We study the set-valued Cauchy equation postulated for orthogonal vectors. We give its general solution as well as we look for selections of functions satisfying the equation
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