471 research outputs found
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Development of a scale to measure individualsâ ratings of peace
Background: The evolving concept of peace-building and the interplay between peace and health is examined in many venues, including at the World Health Assembly. However, without a metric to determine effectiveness of intervention programs all efforts are prone to subjective assessment. This paper develops a psychometric index that lays the foundation for measuring community peace stemming from intervention programs. Methods: After developing a working definition of âpeaceâ and delineating a Peace Evaluation Across Cultures and Environments (PEACE) scale with seven constructs comprised of 71 items, a beta version of the index was pilot-tested. Two hundred and fifty subjects in three sites in the U.S. were studied using a five-point Likert scale to evaluate the psychometric functioning of the PEACE scale. Known groups validation was performed using the SOS-10. In addition, test-retest reliability was performed on 20 subjects. Results: The preliminary data demonstrated that the scale has acceptable psychometric properties for measuring an individualâs level of peacefulness. The study also provides reliability and validity data for the scale. The data demonstrated internal consistency, correlation between data and psychological well-being, and test-retest reliability. Conclusions: The PEACE scale may serve as a novel assessment tool in the health sector and be valuable in monitoring and evaluating the peace-building impact of health initiatives in conflict-affected regions
HD 5388 b is a 69 M_Jup companion instead of a planet
We examined six exoplanet host stars with non-standard Hipparcos astrometric
solution, which may be indicative of unrecognised orbital motion. Using
Hipparcos intermediate astrometric data, we detected the astrometric orbit of
HD 5388 at a significance level of 99.4 % (2.7 sigma). HD 5388 is a
metal-deficient star and hosts a planet candidate with a minimum mass of 1.96
M_J discovered in 2010. We determined its orbit inclination to be i = 178.3
+0.4/-0.7 deg and the corresponding mass of its companion HD 5388 b to be M_2 =
69 +/- 20 M_J. The orbit is seen almost face-on and the companion mass lies at
the upper end of the brown-dwarf mass range. A mass lower than 13 M_J was
excluded at the 3-sigma level. The astrometric motions of the five other stars
had been investigated by other authors revealing two planetary companions, one
stellar companion, and two statistically insignificant orbits. We conclude that
HD 5388 b is not a planet but most likely a brown-dwarf companion. In addition,
we find that the inclinations of the stellar rotation axis and the companion's
orbital axis differ significantly.Comment: 5 pages, 4 figures, Accepted for publication in Astronomy and
Astrophysics Letter
Early Developmental Processes and the Continuity of Risk for Underage Drinking and Problem Drinking
Developmental pathways to underage drinking emerge before the second decade of
life. Many scientists, however, as well as the general public, continue to focus on
proximal influences surrounding the initiation of drinking in adolescence, such as social, behavioral, and genetic variables related to availability and ease of acquisition of the drug, social reinforcement for its use, and individual differences in drug responses. In the past 20 years, a considerable body of evidence has accumulated on the early (often much earlier than the time of the first drink) predictors and pathways of youthful alcohol use and abuse. These early developmental influences involve numerous risk, vulnerability, promotive, and protective processes. Some of these factors are not related directly to alcohol use, whereas others involve learning and expectancies about later drug use that are shaped by social experience. The salience of these factors (identifiable in early childhood) for understanding the course and development of adult alcohol and other drug use disorders is evident from the large and growing body of findings on their ability to predict adult clinical outcomes. This review summarizes the evidence on early pathways toward and away from underage drinking, with a particular focus on the risk and protective factors and the mediators and moderators of risk for underage drinking that become evident during the preschool and early school years. It is guided by a developmental perspective on the aggregation of risk and protection and examines the contributions of biological, psychological, and social processes within the context of normal development.Implications of this evidence for policy, intervention, and future research are discussed.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/65125/1/UM 33 Zucker2008_EarlyDevelopmentalProc.Pediatrics_InPress_.pd
Extrasolar planets in stellar multiple systems
Analyzing exoplanets detected by radial velocity or transit observations, we
determine the multiplicity of exoplanet host stars in order to study the
influence of a stellar companion on the properties of planet candidates.
Matching the host stars of exoplanet candidates detected by radial velocity or
transit observations with online multiplicity catalogs in addition to a
literature search, 57 exoplanet host stars are identified having a stellar
companion. The resulting multiplicity rate of at least 12 percent for exoplanet
host stars is about four times smaller than the multiplicity of solar like
stars in general. The mass and the number of planets in stellar multiple
systems depend on the separation between their host star and its nearest
stellar companion, e.g. the planetary mass decreases with an increasing stellar
separation. We present an updated overview of exoplanet candidates in stellar
multiple systems, including 15 new systems (compared to the latest summary from
2009).Comment: 11 pages, 4 figures, appendix with 6 tables, accepted for publication
in A&
A New Giant Stellar Structure in the Outer Halo of M31
The Sloan Digital Sky Survey has revealed an overdensity of luminous red
giant stars ~ 3 degrees (40 projected kpc) to the northeast of M31, which we
have called Andromeda NE. The line-of-sight distance to Andromeda NE is within
approximately 50 kpc of M31; Andromeda NE is not a physically unrelated
projection. Andromeda NE has a g-band absolute magnitude of ~ -11.6 and central
surface brightness of ~ 29 mag/sq.arcsec, making it nearly two orders of
magnitude more diffuse than any known Local Group dwarf galaxy at that
luminosity. Based on its distance and morphology, Andromeda NE is likely
undergoing tidal disruption. Andromeda NE's red giant branch color is unlike
that of M31's present-day outer disk or the stellar stream reported by Ibata et
al. (2001), arguing against a direct link between Andromeda NE and these
structures. However, Andromeda NE has a red giant branch color similar to that
of the G1 clump; it is possible that these structures are both material torn
off of M31's disk in the distant past, or that these are both part of one
ancient stellar stream.Comment: 11 pages, 3 figures; ApJ Letters accepted versio
Permutability of proofs in intuitionistic sequent calculi
We prove a folklore theorem, that two derivations in a cut-free
sequent calculus for
intuitionistic propositional logic (based on Kleene's {\bf G3}) are
inter-permutable (using a set of
basic "permutation reduction rules'' derived from Kleene's work in 1952) iff
they determine
the same natural deduction. The basic rules form a confluent and weakly
normalising
rewriting system. We refer to Schwichtenberg's proof elsewhere
that a modification of this system is strongly normalising.UniĂŁo Europeia (UE) - Programa ESPRIT BRA 7232 GENTZEN.Centro de MatemĂĄtica da Universidade do Minho (CMAT)
Update on the Nature of Virgo Overdensity
We use the Eighth Data Release of Sloan Digital Sky Survey (SDSS DR8) catalog
with its additional sky coverage of the southern Galactic hemisphere, to
measure the extent and study the nature of the Virgo Overdensity (VOD; Juric et
al. 2008). The data show that the VOD extends over no less than 2000 deg^2,
with its true extent likely closer to 3000 deg^2. We test whether the VOD can
be attributed to a tilt in the stellar halo ellipsoid with respect to the plane
of the Galactic disk and find that the observed symmetry of the north-south
Galactic hemisphere star counts excludes this possibility. We argue that the
Virgo Overdensity, in spite of its wide area and cloud-like appearance, is
still best explained by a minor merger. Its appearance and position is
qualitatively similar to a near perigalacticon merger event and, assuming that
the VOD and the Virgo Stellar Stream share the same progenitor, consistent with
the VSS orbit determined by Casetti-Dinescu et al. (2009).Comment: 9 pages,6 figures; accepted for publication in A
To B or not to B: a question of resolution?
A simple rule of thumb based on resolution is not adequate to identify the best treatment of atomic displacements in macromolecular structural models. The choice to use isotropic B factors, anisotropic B factors, TLS models or some combination of the three should be validated through statistical analysis of the model refinement
Forming Different Planetary Systems
With the increasing number of detected exoplanet samples, the statistical
properties of planetary systems have become much clearer. In this review, we
summarize the major statistics that have been revealed mainly by radial
velocity and transiting observations, and try to interpret them within the
scope of the classical core-accretion scenario of planet formation, especially
in the formation of different orbital architectures for planetary systems
around main sequence stars. Based on the different possible formation routes
for different planet systems, we tentatively classify them into three major
catalogs: hot Jupiter systems, standard systems and distant giant planet
systems. The standard system can be further categorized into three sub-types
under different circumstances: solar-like systems, hot Super-Earth systems,
sub-giant planet systems. We also review the planet detection and formation in
binary systems as well as planets in star clusters.Comment: 27 pages, 2 figures, 1 table, published in "Research in Astron.
Astrophysics." 2012, 12,108
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Insiders, Outsiders, and the Struggle for Consecration in Cultural Fields: A Core-Periphery Perspective
Building on recent research emphasizing how legitimacy depends on consensus among audiences about candidatesâ characteristics and activities, we examine the relationship between cultural producersâ (candidates) position in the social structure and the consecration of their creative work by relevant audiences. We argue that the outcome of this process of evaluation in any cultural field, whether in art or science, is a function of (1) candidatesâ embeddedness within the field, and (2) the type of audienceâthat is, peers versus criticsâevaluating candidatesâ work. Specifically, we hypothesize that peers are more likely to favor candidates who are highly embedded in the field, whereas critics will not show such favoritism. We find support for these hypotheses in the context of the Hollywood motion picture industry
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