1,459 research outputs found
Influence of Mindfulness Practice on Counseling Skills Development
This study assessed the impact of mindfulness practice, incorporated alongside a five-week counselor skills training model, on the counseling skills development of master’s-level trainees (N = 59). Three groups of counseling students were studied: those who engaged in no mindfulness practice; those who engaged in a brief amount of mindfulness practice (five mindfulness practice sessions); and those who engaged in an extended amount of mindfulness practice (11 mindfulness practice sessions). The results showed improvements in counseling skills associated with mindfulness practice, although the brief and extended intervention groups did not significantly differ from one another
Evidence-based management options for women at increased breast/ovarian cancer risk
Recent developments in our ability to predict breast cancer risk necessitates primary care physicians learn to evaluate breast cancer risk and its importance in shaping decisions concerning surveillance and risk reduction measures. This article reviews the current opinion on risk assessment and management of women with an increased risk of breast/ovarian cancer. Management options are given for women at slightly, moderately and highly elevated breast cancer risk, as well as for BRCA1/2 carriers, based on currently available evidenc
New metallicity calibration down to [Fe/H] = -2.75 dex
88 dwarfs, covering the colour index interval 0.37 <(B-V)o <= 1.07 mag, with
metallicities -2.70 <= [Fe/H] <= +0.26 dex have been taken from three different
sources for new metallicity calibration. The catalogue of Cayrel de Stroble et
al. (2001) which includes 65% of the stars in our sample supplies detailed
information on abundances for stars with determination based on high resolution
spectroscopy. 77 stars which supplies at least one of the following conditions
have been used as "corner stones" for constructing the new calibration: (i) the
parallax is larger than 10 mas (distance relative to the Sun less than 100 pc)
and the galactic latitude is absolutely higher than 30 degrees, (ii) the
parallax is rather large, if the galactic latitude is absolutely low and vice
versa. Contrary to the previous investigations, a third-degree polynomial
fitted for the new calibration: [Fe/H] = 0.10-2.76d-24.04d^2+30.00d^3. The
coefficients were evaluated by the least-square method, without regarding the
metallicity of Hyades. However, the constant term is in the range of
metallicity determined for this cluster i.e.: 0.08 <= [Fe/H] <= 0.11 dex. The
mean deviation and the mean error in our work are equal to those of Carney
(1979), for [Fe/H] >= -1.75 dex where Carney's calibration is valid.Comment: 22 pages, 5 figures. accepted for PASA, Vol 20, No
The impact of pollution on stellar evolution models
An approach is introduced for incorporating the concept of stellar pollution
into stellar evolution models. The approach involves enhancing the metal
content of the surface layers of stellar models. In addition, the surface
layers of stars in the mass range of 0.5-2.0 Solar masses are mixed to an
artificial depth motivated by observations of lithium abundance. The behavior
of polluted stellar evolution models is explored assuming the pollution occurs
after the star has left the fully convective pre main sequence phase. Stellar
models polluted with a few Earth masses of iron are significantly hotter than
stars of the same mass with an equivalent bulk metallicity. Polluted stellar
evolution models can successfully reproduce the metal-rich, parent star tau
Bootis and suggest a slightly lower mass than standard evolution models.
Finally, the possibility that stars in the Hyades open cluster have accreted an
average of 0.5 Earth masses of iron is explored. The results indicate that it
is not possible to rule out stellar pollution on this scale from the scatter of
Hyades stars on a color-magnitude diagram. The small amount of scatter in the
observational data set does rule out pollution on the order of 1.5 Earth masses
of iron. Pollution effects at the low level of 0.5 Earth masses of iron do not
produce substantial changes in a star's evolution.Comment: 14 pages, 3 figures, AASTeX, to appear in the 10/10/03 issue of Ap
Z-11-TETRADECENYL ACETATE: SEX ATTRACTANT OF AGAPETA ZOEGANA (LEPIDOPTERA: TORTRICIDAE), A POTENTIAL SPECIES FOR THE BIOLOGICAL CONTROL OF KNAPWEED
In Canada, 78 of the most important weed species are introductions from Eurasia (Frankton and Mulligan 1970). Classical biological control aims to reduce the density of alien weeds below the economic threshold through introduction of specific herbivores from the native distribution area (Peschken 1979). During extended field surveys in central and southeastern Europe, the Commonwealth Institute of Biological Control established the root-mining tortricid Agapeta zoegana Haw. as a promising control agent for Centaurea diffusa Lam. and C. maculosa Lam., 2 important ranch weeds in southwestern Canada (Harris and Myers 1984) and the northwestern United States (Maddox 1982). Due to the limited host range and suitable climatic conditions this moth was chosen for introduction into North America (Müller et al. 1982; Müller 1984). We wish to report an attractant that may be used to monitor the establishment of this beneficial species in its new habita
Development of polymorphic microsatellite markers for the critically endangered and endemic Indian dipterocarp, Vateria indica L. (Dipterocarpaceae)
Vateria indica (Dipterocarpaceae) is an economically and ecologically important canopy tree endemic to the Western Ghats, India. The species has undergone extensive habitat loss and overexploitation and is therefore listed as ‘critically endangered' on the 2012 IUCN Red List. We developed ten polymorphic microsatellite loci for V. indica. In addition, we confirm cross amplification and variation in two loci isolated from the closely related but geographically disjunct species Vateriopsis seychellarum, previously published by Finger et al. Conserv Genet Resour, 2 (S1):309-311, (2010). The twelve microsatellite primers screened on 48 adult samples of V. indica had 5-11 alleles per locus (mean of 8.5 per locus) with an average polymorphic information content of 0.64 across loci. Expected heterozygosity ranged from 0.44 to 0.84. These markers will enable us to quantify population genetic diversity in habitat fragments and to study fine scale spatial genetic structure and contemporary gene flo
The Star Formation Epoch of the Most Massive Early-Type Galaxies
We present new Keck spectroscopy of early-type galaxies in three galaxy
clusters at z~0.5. We focus on the fundamental plane (FP) relation, and combine
the kinematics with structural parameters determined from HST images. The
galaxies obey clear FP relations, which are offset from the FP of the nearby
Coma cluster due to passive evolution of the stellar populations. The z~0.5
data are combined with published data for 11 additional clusters at
0.18<z<1.28, to determine the evolution of the mean M/L(B) ratio of cluster
galaxies with masses M>10^11 M_sun, as implied by the FP. We find
dlog(M/L(B))/dz = -0.555+-0.042, stronger evolution than was previously
inferred from smaller samples. The observed evolution depends on the
luminosity-weighted mean age of the stars in the galaxies, the initial mass
function (IMF), selection effects due to progenitor bias, and other parameters.
Assuming a normal IMF but allowing for various other sources of uncertainty we
find z* = 2.01+-0.20 for the luminosity-weighted mean star formation epoch. The
main uncertainty is the slope of the IMF in the range 1-2 Solar masses: we find
z* = 4.0 for a top-heavy IMF with slope x=0. The M/L(B) ratios of the cluster
galaxies are compared to those of recently published samples of field
early-type galaxies at 0.32<z<1.14. Assuming that progenitor bias and the IMF
do not depend on environment we find that the present-day age of stars in
massive field galaxies is 4.1 +- 2.0 % (~0.4 Gyr) less than that of stars in
massive cluster galaxies, consistent with most, but not all, previous studies
of local and distant early-type galaxies. This relatively small age difference
is surprising in the context of expectations from ``standard'' hierarchical
galaxy formation models. [ABRIDGED]Comment: Accepted for publication in ApJ. Minor corrections to match published
versio
The Peculiar Type Ia Supernova 1999by: Spectroscopy at Early Epochs
We present medium resolution (lambda/Delta lambda = 2500) optical
spectroscopy of SN 1999by in NGC 2841 made around its light maximum. The depth
ratio of the two Si II features at 5800 AA and 6150 AA being R(SiII) approx.
0.63 at maximum indicates that this SN belongs to the peculiar, sub-luminous
SNe Ia. Radial velocities inferred from the minimum of the 6150 AA trough
reveal a steeper decline of the velocity curve than expected for ``normal'' SNe
Ia, consistent with the behavior of published VRI light curves. A revised
absolute magnitude of SN 1999by and distance to its host galaxy NGC 2841 is
estimated based on the Multi-Color Light Curve Shape (MLCS) method, resulting
in M_V(max)=-18.06+/- 0.1 mag and d = 17.1+/-1.2 Mpc, respectively. An
approximative linear dependence of the luminosity parameter Delta on R(SiII) is
presented.Comment: accepted for publication in Astron. Journal (2001 June
The uBVI Photometric System. I. Motivation, Implementation, and Calibration
This paper describes the design principles for a CCD-based photometric system
that is highly optimized for ground-based measurement of the size of the Balmer
jump in stellar energy distributions. It is shown that, among ultraviolet
filters in common use, the Thuan-Gunn u filter is the most efficient for this
purpose. This filter is combined with the standard Johnson-Kron-Cousins B, V,
and I bandpasses to constitute the uBVI photometric system.
Model stellar atmospheres are used to calibrate color-color diagrams for the
uBVI system in terms of the fundamental stellar parameters of effective
temperature, surface gravity, and metallicity. The u-B index is very sensitive
to log g, but also to [Fe/H]. It is shown that an analog of the Str\"omgren c_1
index, defined as (u-B)-(B-V), is much less metallicity dependent, but still
sensitive to log g. The effect of interstellar reddening on u-B is determined
through synthetic photometric calculations, and practical advice is given on
dealing with flat fields, atmospheric extinction, the red leak in the u filter,
and photometric reductions.
The uBVI system offers a wide range of applicability in detecting stars of
high luminosity in both young (yellow supergiants) and old (post-AGB stars)
populations, using stars of both types as standard candles to measure
extragalactic distances with high efficiency, and in exploring the horizontal
branch in globular clusters. In many stellar applications, it can profitably
replace the classical uBVI system.
Paper II in this series will present a network of well-calibrated standard
stars for the uBVI system.Comment: 24 pages, 5 figures, 4 tables; accepted by A
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