1,334 research outputs found
Deceptive Practices: The Issue of âBullying-to-Suicideâ in the U.S. Army
poster abstractThe United States Department of Defense reported that 182 activeâduty Army soldiers took their own lives in 2012. Several key factors contributing to this high rate of suicide, such as Post-traumatic Stress Syndrome (PTSD) and depression and Traumatic Brain Injury (TBI) have been intensely researched. This poster represents exploratory research on the issue of suicide in the military; paying particular attention to the practice of informal negative sanctions. Data on this issue was obtained from numerous articles, reports and qualitative interviews conducted with active-duty Army personnel and recently separated Army veterans. This study not only describes warâs impact on humanâs mental health and the hidden realities of Army life. It additionally assesses how interpersonal procedures operate on different ranges
Designing pseudocubic perovskites with enhanced nanoscale polarization
A crystal-chemical framework has been proposed for the design of pseudocubic perovskites with
nanoscale ferroelectric order, and its applicability has been demonstrated using a series of represen-
tative solid solutions that combined ferroelectric (K
0.5
Bi
0.5
TiO
3
, BaTiO
3
, and PbTiO
3
) and antifer-
roelectric (Nd-substituted BiFeO
3
) end members. The pseudocubic structures obtained in these
systems exhibited distortions that were coherent on a scale ranging from sub-nanometer to tens of
nanometers, but, in all cases, the macroscopic distortion remained unresolvable even if using high-
resolution X-ray powder diffraction. Different coherence lengths for the local atomic displacements
account for the distinctly different dielectric, ferroelectric, and electromechanical properties exhib-
ited by the samples. The guidelines identified provide a rationale for chemically tuning the coher-
ence length to obtain the desired functional response
Kaneohe Bay Sewage Diversion Experiment: Perspectives on Ecosystem Responses to Nutritional Perturbation
Kaneohe Bay, Hawaii, received increasing amounts of sewage
from the 1950s through 1977. Most sewage was diverted from the bay in 1977
and early 1978. This investigation, begun in January 1976 and continued
through August 1979, described the bay over that period, with particular
reference to the responses of the ecosystem to sewage diversion.
The sewage was a nutritional subsidy. All of the inorganic nitrogen and
most of the inorganic phosphorus introduced into the ecosystem were taken
up biologically before being advected from the bay. The major uptake was by
phytoplankton, and the internal water-column cycle between dissolved nutrients,
phytoplankton, zooplankton, microheterotrophs, and detritus supported
a rate of productivity far exceeding the rate of nutrient loading.
These water-column particles were partly washed out of the ecosystem and
partly sedimented and became available to the benthos. The primary benthic
response to nutrient loading was a large buildup of detritivorous heterotrophic
biomass. Cycling of nutrients among heterotrophs, autotrophs, detritus, and
inorganic nutrients was important.
With sewage diversion, the biomass of both plankton and benthos decreased
rapidly. Benthic biological composition has not yet returned to presewage
conditions, partly because some key organisms are long-lived and partly
because the bay substratum has been perturbed by both the sewage and other
human influences
C, S, Zn and Cu abundances in planet-harbouring stars
We present a detailed and uniform study of C, S, Zn and Cu abundances in a
large set of planet host stars, as well as in a homogeneous comparison sample
of solar-type dwarfs with no known planetary-mass companions. Carbon abundances
were derived by {EW} measurement of two C I optical lines, while spectral
syntheses were performed for S, Zn and Cu. We investigated possible differences
in the behaviours of the volatiles C, S and Zn and in the refractory Cu in
targets with and without known planets in order to check possible anomalies due
to the presence of planets. We found that the abundance distributions in stars
with exoplanets are the high [Fe/H] extensions of the trends traced by the
comparison sample. All volatile elements we studied show [X/Fe] trends
decreasing with [Fe/H] in the metallicity range -0.8<[Fe/H]<0.5, with
significantly negative slopes of -0.39+-0.04 and -0.35+-0.04 for C and S,
respectively. A comparison of our abundances with those available in the
literature shows good agreement in most cases.Comment: 28 pages, 13 figures, accepted for publication in A&
Nanoscale polar heterogeneities and branching Bi-displacement directions in K0.5Bi0.5TiO3
K0.5Bi0.5TiO3 (KBT)âone of the few perovskite-like ferroelectric compounds with room-temperature tetragonal symmetryâdiffers from other members of its family (BaTiO3 and PbTiO3) by the presence of a disordered mixture of K and Bi on cuboctahedral sites. This disorder is expected to affect local atomic displacements and their response to an applied electric field. We have derived nanoscale atomistic models of KBT by refining atomic coordinates to simultaneously fit neutron/X-ray total scattering and extended X-ray absorption fine-structure data. Both Bi and Ti ions were found to be offset relative to their respective oxygen cages in the high-temperature cubic phase; in contrast, the coordination environment of K remained relatively undistorted. In the cubic structure, Bi displacements prefer the âš100â© directions and the probability density distribution of Bi features six well-separated sites; a similar preference exists for the much smaller Ti displacements, although the split sites for Ti could not be resolved. The cation displacements are correlated, yielding polar nanoregions, whereas on average, the structure appears as cubic. The cubic â tetragonal phase transition involves both order/disorder and displacive mechanisms. A qualitative change in the form of the Bi probability density distribution occurs in the tetragonal phase on cooling to room temperature because Bi displacements âbranch offâ to âš111â© directions. This change, which preserves the average symmetry, is accompanied by the development of nanoscale polar heterogeneities that exhibit significant deviations of their polarization vectors from the average polar axis
Differential Impact of Serial Measurement of Nonplatelet Thromboxane Generation on Long-Term Outcome After Cardiac Surgery.
BACKGROUND: Systemic thromboxane generation, not suppressible by standard aspirin therapy and likely arising from nonplatelet sources, increases the risk of atherothrombosis and death in patients with cardiovascular disease. In the RIGOR (Reduction in Graft Occlusion Rates) study, greater nonplatelet thromboxane generation occurred early compared with late after coronary artery bypass graft surgery, although only the latter correlated with graft failure. We hypothesize that a similar differential association exists between nonplatelet thromboxane generation and long-term clinical outcome.
METHODS AND RESULTS: Five-year outcome data were analyzed for 290 RIGOR subjects taking aspirin with suppressed platelet thromboxane generation. Multivariable modeling was performed to define the relative predictive value of the urine thromboxane metabolite, 11-dehydrothromboxane B
CONCLUSIONS: Long-term nonplatelet thromboxane generation after coronary artery bypass graft surgery is a novel risk factor for 5-year adverse outcome, including death. In contrast, nonplatelet thromboxane generation in the early postoperative period appears to be driven predominantly by inflammation and did not independently predict long-term clinical outcome
A Qualitative Analysis of Women's Short Accounts of Labour and Birth in a Western Australian Public Tertiary Hospital
This paper reports the findings of the postnatal qualitative arm of a larger study,which investigated women's prenatal and postnatal levels of childbirth fear. Women's expectations and experiences of labour and birth in a Western Australian public tertiary hospital were identified following thematic analysis of short written accounts from 141 participants who had given birth in the previous 6 to 14 weeks. Four major categories emerged to describe features and mediating factors in the trajectory of childbirth and the early puerperium "Anticipating Labour and Birth", "Labour and birth Depicted", "Mediating Factors and their consequences" and "Evaluating, Resolving, and Looking Ahead" portray women's comparative reflections on expectations and realities of birth, on mediating influences, and on moving on from their experience. These findings will provide maternity care professionals with insight into the personal and environmental features of the childbirth setting which colours women's recollections. Being aware of what women value during labour and birth will reinforce the need for professionals to provide care using a mindful approach that considers the potential psychological, emotional and behavioural implications of events
Searching for the signatures of terrestial planets in solar analogs
We present a fully differential chemical abundance analysis using very
high-resolution (R >~ 85,000) and very high signal-to-noise (S/N~800 on
average) HARPS and UVES spectra of 7 solar twins and 95 solar analogs, 24 are
planet hosts and 71 are stars without detected planets. The whole sample of
solar analogs provide very accurate Galactic chemical evolution trends in the
metalliciy range -0.3<[Fe/H]<0.5. Solar twins with and without planets show
similar mean abundance ratios. We have also analysed a sub-sample of 28 solar
analogs, 14 planet hosts and 14 stars without known planets, with spectra at
S/N~850 on average, in the metallicity range 0.14<[Fe/H]<0.36 and find the same
abundance pattern for both samples of stars with and without planets. This
result does not depend on either the planet mass, from 7 Earth masses to 17.4
Jupiter masses, or the orbital period of the planets, from 3 to 4300 days. In
addition, we have derived the slope of the abundance ratios as a function of
the condensation temperature for each star and again find similar distributions
of the slopes for both stars with and without planets. In particular, the peaks
of these two distributions are placed at a similar value but with opposite sign
as that expected from a possible signature of terrestial planets. In
particular, two of the planetary systems in this sample, containing each of
them a Super-Earth like planet, show slope values very close to these peaks
which may suggest that these abundance patterns are not related to the presence
of terrestial planets.Comment: Accepted for publication in The Astrophysical Journa
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Profiling complex word usage in the speech of English preschool children: frequency patterns and transparency characteristics
This corpus-based study provides a baseline of complex word usage patterns in the spontaneous speech of English preschool children to ascertain the characteristics of their derivative vocabulary before literacy development affects language skills. Frequencies of suffixed derivatives produced by (N=243) children aged 2-5 and their caregivers were extracted for 58 suffix variants, yielding 558 types from the former and 1,364 from the latter. Between the youngest and oldest groups, 11 suffix categories increased significantly in type frequency, compared with 22 in the caregiver dataset. All derivative types were classified for transparency of meaning and simplicity of form on a 5-point analysability scale. Around 59% of both the child and caregiver derivative vocabulary sets were classified as transparent regardless of age, suggesting that the potential analysability of the preschool childâs input remains surprisingly invariant over time. The study provides baseline data for future studies on the development of morphological awareness in English-speaking schoolchildren
CymantreneâTriazole "Click" Products: Structural Characterization and Electrochemical Properties
We report the first known examples of triazole-derivatized cymantrene complexes (η5-[4-substituted triazol-1-yl]cyclopentadienyl)tricarbonylmanganese(I), obtained via a âclickâ chemical synthesis, bearing a phenyl, 3-aminophenyl, or 4-aminophenyl moiety at the 4-position of the triazole ring. Structural characterization data using multinuclear NMR, UVâvis, ATR-IR, and mass spectrometric methods are provided, as well as crystallographic data for (η5-[4-phenyltriazol-1-yl]cyclopentadienyl)tricarbonylmanganese(I) and (η5-[4-(3-aminophenyl)triazol-1-yl]cyclopentadienyl)tricarbonylmanganese(I). Cyclic voltammetric characterization of the redox behavior of each of the three cymantreneâtriazole complexes is presented together with digital simulations, in situ infrared spectroelectrochemistry, and DFT calculations to extract the associated kinetic and thermodynamic parameters. The trypanocidal activity of each cymantreneâtriazole complex is also examined, and these complexes are found to be more active than cymantrene alone
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