9,378 research outputs found
Matching the High Momentum Modes in a Truncated Determinant Algorithm
Within a truncated determinant algorithm, two alternatives are discussed for
including systematically the remaining ultraviolet modes. Evidence is presented
that these modes are accurately described by an effective action involving only
small Wilson loops.Comment: LATTICE98(algorithms) ; typos correcte
Risk identification and management for the research use of government administrative data
Purpose – Government administrative data have enormous potential for public and individual benefit
through improved educational and health services to citizens, medical research, environmental and climate
interventions and better use of scarce energy resources. The purpose of this study (part of the Administrative
Data Research Centre in England, ADRC-E) was to examine perspectives about the sharing, linking and reuse (secondary use) of government administrative data. This study seeks to establish an analytical
understanding of risk with regard to administrative data.
Design/methodology/approach – This qualitative study focused on the secondary use of government
administrative data by academic researchers. Data collection was through 44 semi-structured interviews plus
one focus group, and was supported by documentary analysis and a literature review. The study draws on the
views of expert data researchers, data providers, regulatory bodies, research funders, lobby groups,
information practitioners and data subjects.
Findings – This study discusses the identification and management of risk in the use of government
administrative data and presents a risk framework.
Practical implications – This study will have resonance with records managers, risk managers, data
specialists, information policy and compliance managers, citizens groups that engage with data, as well as all
those responsible for the creation and management of government administrative data.
Originality/value – First, this study identifies and categorizes the risks arising from the research use of
government administrative data, based on policy, practice and experience of those involved. Second, it
identifies mitigating risk management activities, linked to five key stakeholder communities, and it discusses
the locus of responsibility for risk management actions. The conclusion presents the elements of a new risk
framework to inform future actions by the government data community and enable researchers to exploit the
power of administrative data for public good
The nonperturbative decay of SUSY flat directions
We compute the nonperturbative decay of supersymmetric flat directions due to
their D-term potential. Flat directions can develop large vacuum expectation
values (vevs) during inflation, and, if they are long-lived, this can strongly
affect the reheating and thermalization stages after the inflation. We study a
generic system of two U(1) or SU(2) flat directions which are cosmologically
evolving after inflation. After proper gauge fixing, we show that the
excitations of the fields around this background can undergo exponential
amplification, at the expense of the energy density of the flat directions. We
compute this effect for several values of the masses and the initial vevs of
the two flat directions, through a combination of analytical methods and
extensive numerical simulations. For a wide range of parameters the flat
directions decay within their first few rotations.Comment: 29 pages, 7 .ps figure
Unquenching the scalar glueball
Computations in the quenched approximation on the lattice predict the
lightest glueball to be a scalar in the 1.5-1.8 GeV region. Here we calculate
the dynamical effect the coupling to two pseudoscalars has on the mass, width
and decay pattern of such a scalar glueball. These hadronic interactions allow
mixing with the scalar nonet, which is largely fixed by the
well-established K_0^*(1430). This non-perturbative mixing means that, if the
pure gluestate has a width to two pseudoscalar channels of ~100 MeV as
predicted on the lattice, the resulting hadron has a width to these channels of
only ~30 MeV with a large eta-eta component. Experimental results need to be
reanalyzed in the light of these predictions to decide if either the f_0(1500)
or an f_0(1710) coincides with this dressed glueball.Comment: 12 pages, LaTex, 3 Postscript figure
Evaluating Diet Composition of Pronghorn in Wind Cave National Park, South Dakota
The pronghorn (Antilocapra americana) was reintroduced into Wind Cave National Park (WCNP), South Dakota, in 1914, and thus, has inhabited the Park for nearly a century. During the 1990\u27s, a decline in the population raised concern for the continued existence of pronghorn inside WCNP; an investigation into the observed decline was initiated. Primary objectives of our study were to evaluate diet composition and forage selection by pronghorn in WCNP. Microhistological analysis was conducted on 58 fecal samples collected opportunistically from pronghorn during 2002. Blue grama (Bouteloua gracilis), common juniper (Juniperus communis), and northern bedstraw (Galium boreale) were identified as major seasonal food items, representing 14.6, l 0.6, and 6.5 % of the annual diet, respectively. Annual diets of pronghorn in WCNP included 41.5% grasses, 31.1% shrubs, and 27.4% forbs. Total forage production in WCNP was 2% grass, 4% shrubs, and 23% forbs. Results indicated strong dietary selection by pronghorn for shrubs
Force distribution in a scalar model for non-cohesive granular material
We study a scalar lattice model for inter-grain forces in static,
non-cohesive, granular materials, obtaining two primary results. (i) The
applied stress as a function of overall strain shows a power law dependence
with a nontrivial exponent, which moreover varies with system geometry. (ii)
Probability distributions for forces on individual grains appear Gaussian at
all stages of compression, showing no evidence of exponential tails. With
regard to both results, we identify correlations responsible for deviations
from previously suggested theories.Comment: 16 pages, 9 figures, Submitted to PR
Psychometric Characteristics of the Connor-Davidson Resilience Scale (CD-RISC) in Postpartum Mothers with Histories of Childhood Maltreatment
Background: There is increased awareness that resilience serves as a protective factor against adverse psychophysiological sequelae in the context of stress. However, there are few instruments to assess this construct in adult populations. The Connor-Davidson resilience scale (CD-RISC) has been developed to assess adaptation following stress exposure. While this instrument has previously demonstrated impressive reliability and construct validity, prior research has not supported the consistency of the originally described factor structure. There is also limited evidence regarding the measurement of resilience in the context of cumulative stress exposure.
Objectives: This research explores the psychometric properties of the CD-RISC in mothers with childhood histories of maltreatment
Materials and Methods: Postpartum women who endorsed a history of childhood abuse or neglect (N = 141) completed the CD-RISC, the childhood trauma questionnaire and other surveys measuring positive and negative health and functioning. We calculated descriptive statistics with percentage counts and means as appropriate. Internal reliability was evaluated by Cronbach’s alpha and the calculation of item-to-total score correlations. Parallel analysis (PA) was utilized to derive the number of retained factors.
Results: A recent parenting transition concomitant with a history of maltreatment was associated with lower CD-RISC scores. Internal reliability and concurrent validity analyses were satisfactory and consistent with predicted hypotheses. Exploratory factor analysis (EFA) supported a four-factor model of resilience with this population.
Conclusions: This research offers further evidence of the reliability and validity of the CD-RISC. Further, the results of the EFA with parallel analysis offer an empirically-driven derivation of factors for this population
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