728 research outputs found
Interactions of Water, Plants and Ground-Dwelling Fauna: Water Harvesting and Tapping by Trapdoor Spiders
Beyond Instructions to Disregard: When Objections Backfire and Interruptions Distract
Researchers have proposed many explanations for the replicated finding that jurors often fail to disregard evidence when instructed by a judge to do so. We propose a novel explanation: that the act of objecting may cause the effect because an objection (a) draws attention to the testimony and (b) heightens the perceived importance of the testimony (because of the implication that the objecting party wants to prevent jurors from using it). In previous studies, the act of objecting has always been confounded with the presence of the critical (objected-to) testimony. We devised two new experimental conditions that unconfound these factors. We found that whereas objections increase the use of objected-to (incriminating) testimony, random (non-objection) interruptions decrease use of this testimony. We conclude that, unlike random interruptions, an objection communicates to the jurors that an attorney is concerned about the objected-to testimony, increasing the perceived importance of that testimony
Only watching others making their experiences is insufficient to enhance adult neurogenesis and water maze performance in mice
In the context of television consumption and its opportunity costs the
question arises how far experiencing mere representations of the outer world
would have the same neural and cognitive consequences than actively
interacting with that environment. Here we demonstrate that physical
interaction and direct exposition are essential for the beneficial effects of
environmental enrichment. In our experiment, the mice living in a simple
standard cage placed in the centre of a large enriched environment only
indirectly experiencing the stimulus-rich surroundings (IND) did not display
increased adult hippocampal neurogenesis. In contrast, the mice living in and
directly experiencing the surrounding enriched environment (DIR) and mice
living in a similar enriched cage containing an uninhabited inner cage (ENR)
showed enhanced neurogenesis compared to mice in control conditions (CTR).
Similarly, the beneficial effects of environmental enrichment on learning
performance in the Morris Water maze depended on the direct interaction of the
individual with the enrichment. In contrast, indirectly experiencing a
stimulus-rich environment failed to improve memory functions indicating that
direct interaction and activity within the stimulus-rich environment are
necessary to induce structural and functional changes in the hippocampus
Lessons Learned from Testing the Quality Cost Model of Advanced Practice Nursing (APN) Transitional Care
Purpose To describe the development, testing, modification, and results of the Quality Cost Model of Advanced Practice Nurses (APNs) Transitional Care on patient outcomes and health care costs in the United States over 22 years, and to delineate what has been learned for nursing education, practice, and further research. Organizing Construct The Quality Cost Model of APN Transitional Care. Methods Review of published results of seven randomized clinical trials with very low birth-weight (VLBW) infants; women with unplanned cesarean births, high risk pregnancies, and hysterectomy surgery; elders with cardiac medical and surgical diagnoses and common diagnostic related groups (DRGs); and women with high risk pregnancies in which half of physician prenatal care was substituted with APN care. Ongoing work with the model is linking the process of APN care with the outcomes and costs of care. Findings APN intervention has consistently resulted in improved patient outcomes and reduced health care costs across groups. Groups with APN providers were rehospitalized for less time at less cost, reflecting early detection and intervention. Optimal number and timing of postdischarge home visits and telephone contacts by the APNs and patterns of rehospitalizations and acute care visits varied by group. Conclusions To keep people well over time, APNs must have depth of knowledge and excellent clinical and interpersonal skills that are the hallmark of specialist practice, an in-depth understanding of systems and how to work within them, and sufficient patient contact to effect positive outcomes at low cost
ALFALFA HI Data Stacking I. Does the Bulge Quench Ongoing Star Formation in Early-Type Galaxies?
We have carried out an HI stacking analysis of a volume-limited sample of
~5000 galaxies with imaging and spectroscopic data from GALEX and the Sloan
Digital Sky Survey, which lie within the current footprint of the Arecibo
Legacy Fast ALFA (ALFALFA) Survey. Our galaxies are selected to have stellar
masses greater than 10^10 Msun and redshifts in the range 0.025<z<0.05. We
extract a sub-sample of 1833 "early-type" galaxies with inclinations less than
70deg, with concentration indices C>2.6 and with light profiles that are well
fit by a De Vaucouleurs model. We then stack HI line spectra extracted from the
ALFALFA data cubes at the 3-D positions of the galaxies from these two samples
in bins of stellar mass, stellar mass surface density, central velocity
dispersion, and NUV-r colour. We use the stacked spectra to estimate the
average HI gas fractions M_HI/M_* of the galaxies in each bin.
Our main result is that the HI content of a galaxy is not influenced by its
bulge. The average HI gas fractions of galaxies in both our samples correlate
most strongly with NUV-r colour and with stellar surface density. The relation
between average HI fraction and these two parameters is independent of
concentration index C. We have tested whether the average HI gas content of
bulge-dominated galaxies on the red sequence, differs from that of late-type
galaxies on the red sequence. We find no evidence that galaxies with a
significant bulge component are less efficient at turning their available gas
reservoirs into stars. This result is in contradiction with the "morphological
quenching" scenario proposed by Martig et al. (2009).Comment: 21 pages, 15 figures. Accepted for publication in MNRAS. Version with
high resolution figures available at
http://www.mpa-garching.mpg.de/GASS/pubs.ph
The clustering of galaxies as a function of their photometrically-estimated atomic gas content
We introduce a new photometric estimator of the HI mass fraction (M_HI/M_*)
in local galaxies, which is a linear combination of four parameters: stellar
mass, stellar surface mass density, NUV-r colour, and g-i colour gradient. It
is calibrated using samples of nearby galaxies (0.025<z<0.05) with HI line
detections from the GASS and ALFALFA surveys, and it is demonstrated to provide
unbiased M_HI/M_* estimates even for HI-rich galaxies. We apply this estimator
to a sample of ~24,000 galaxies from the SDSS/DR7 in the same redshift range.
We then bin these galaxies by stellar mass and HI mass fraction and compute
projected two point cross-correlation functions with respect to a reference
galaxy sample. Results are compared with predictions from current semi-analytic
models of galaxy formation. The agreement is good for galaxies with stellar
masses larger than 10^10 M_sun, but not for lower mass systems. We then extend
the analysis by studying the bias in the clustering of HI-poor or HI-rich
galaxies with respect to galaxies with normal HI content on scales between 100
kpc and ~5 Mpc. For the HI-deficient population, the strongest bias effects
arise when the HI-deficiency is defined in comparison to galaxies of the same
stellar mass and size. This is not reproduced by the semi-analytic models,
where the quenching of star formation in satellites occurs by "starvation" and
does not depend on their internal structure. HI-rich galaxies with masses
greater than 10^10 M_sun are found to be anti-biased compared to galaxies with
"normal" HI content. Interestingly, no such effect is found for lower mass
galaxies.Comment: 14 pages, 10 figures, accepted for publication in MNRAS, slightly
revised in the tex
The GALEX Arecibo SDSS survey: III. Evidence for the Inside-Out Formation of Galactic Disks
We analyze a sample of galaxies with stellar masses greater than and with redshifts in the range for which HI mass
measurements are available from the GALEX Arecibo SDSS Survey (GASS) or from
the Arecibo Legacy Fast ALFA survey (ALFALFA). At a given value of , our
sample consists primarily of galaxies that are more HI-rich than average. We
constructed a series of three control samples for comparison with these HI-rich
galaxies. As expected, HI-rich galaxies differ strongly from galaxies of same
stellar mass that are selected without regard to HI content. The majority of
these differences are attributable to the fact that galaxies with more gas are
bluer and more actively star-forming. In order to identify those galaxy
properties that are causally connected with HI content, we compare results
derived for the HI sample with those derived for galaxies matched in stellar
mass, size and NUV- colour. The only photometric property that is clearly
attributable to increasing HI content, is the colour gradient of the galaxy.
Galaxies with larger HI fractions have bluer, more actively star-forming outer
disks compared to the inner part of the galaxy. HI-rich galaxies also have
larger -band radii compared to -band radii. Our results are consistent
with the "inside-out" picture of disk galaxy formation, which has commonly
served as a basis for semi-analytic models of the formation of disks in the
context of Cold Dark Matter cosmologies. The lack of any intrinsic connection
between HI fraction and galaxy asymmetry suggests that gas is accreted smoothly
onto the outer disk.Comment: 18 pages, 20 figures. Accepted for publication in MNRAS. GASS
publications and released data can be found at
http://www.mpa-garching.mpg.de/GASS/index.ph
Charmed meson decay constants in three-flavor lattice QCD
We present the first lattice QCD calculation with realistic sea quark content
of the D^+ meson decay constant f_{D^+}. We use the MILC Collaboration's
publicly available ensembles of lattice gauge fields, which have a quark sea
with two flavors (up and down) much lighter than a third (strange). We obtain
f_{D^+} = 201 +/- 3 +/- 17 MeV, where the errors are statistical and a
combination of systematic errors. We also obtain f_{D_s} = 249 +/- 3 +/- 16 MeV
for the D_s meson.Comment: note added on recent CLEO measurement; PRL versio
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