870 research outputs found
Chiral dynamics in form factors, spectral-function sum rules, meson-meson scattering and semilocal duality
In this work, we perform the one-loop calculation of the scalar and
pseudoscalar form factors in the framework of U(3) chiral perturbation theory
with explicit tree level exchanges of resonances. The meson-meson scattering
calculation from Ref.[1] is extended as well. The spectral functions of the
nonet scalar-scalar (SS) and pseudoscalar-pseudoscalar (PP) correlators are
constructed by using the corresponding form factors. After fitting the unknown
parameters to the scattering data, we discuss the resonance content of the
resulting scattering amplitudes. We also study spectral-function sum rules in
the SS-SS, PP-PP and SS-PP sectors as well as semi-local duality from
scattering. The former relate the scalar and pseudoscalar spectra between
themselves while the latter mainly connects the scalar spectrum with the vector
one. Finally we investigate these items as a function of Nc for Nc > 3. All
these results pose strong constraints on the scalar dynamics and spectroscopy
that are discussed. They are successfully fulfilled by our meson-meson
scattering amplitudes and spectral functions.Comment: 45 pages, 17 figures and 4 tables. To match the published version in
PRD: a new paragraph is added in the Introduction and two new references are
include
Data for improvement and clinical excellence: protocol for an audit with feedback intervention in long-term care
<p>Abstract</p> <p>Background</p> <p>There is considerable evidence about the effectiveness of audit coupled with feedback, although few audit with feedback interventions have been conducted in long-term care (LTC) settings to date. In general, the effects have been found to be modest at best, although in settings where there has been little history of audit and feedback, the effects may be greater, at least initially. The primary purpose of the Data for Improvement and Clinical Excellence (DICE) Long-Term Care project is to assess the effects of an audit with feedback intervention delivered monthly over 13 months in four LTC facilities. The research questions we addressed are:</p> <p indent="1">1. What effects do feedback reports have on processes and outcomes over time?</p> <p indent="1">2. How do different provider groups in LTC and home care respond to feedback reports based on data targeted at improving quality of care?</p> <p>Methods/design</p> <p>The research team conducting this study comprises researchers and decision makers in continuing care in the province of Alberta, Canada. The intervention consists of monthly feedback reports in nine LTC units in four facilities in Edmonton, Alberta. Data for the feedback reports comes from the Resident Assessment Instrument Minimum Data Set (RAI) version 2.0, a standardized instrument mandated for use in LTC facilities throughout Alberta. Feedback reports consist of one page, front and back, presenting both graphic and textual information. Reports are delivered to all staff working in the four LTC facilities. The primary evaluation uses a controlled interrupted time series design both adjusted and unadjusted for covariates. The concurrent process evaluation uses observation and self-report to assess uptake of the feedback reports. Following the project phase described in this protocol, a similar intervention will be conducted in home care settings in Alberta. Depending on project findings, if they are judged useful by decision makers participating in this research team, we plan dissemination and spread of the feedback report approach throughout Alberta.</p
Nursing home administratorsâ perspectives on a study feedback report : a cross sectional survey
BackgroundThis project is part of the Translating Research in Elder Care (TREC) program of research, a multi-level and longitudinal research program being conducted in 36 nursing homes in three Canadian Prairie Provinces. The overall goal of TREC is to improve the quality of care for older persons living in nursing homes and the quality of work life for care providers. The purpose of this paper is to report on development and evaluation of facility annual reports (FARs) from facility administrators’ perspectives on the usefulness, meaningfulness, and understandability of selected data from the TREC survey. MethodsA cross sectional survey design was used in this study. The feedback reports were developed in collaboration with participating facility administrators. FARs presented results in four contextual areas: workplace culture, feedback processes, job satisfaction, and staff burnout. Six weeks after FARs were mailed to each administrator, we conducted structured telephone interviews with administrators to elicit their evaluation of the FARs. Administrators were also asked if they had taken any actions as a result of the FAR. Descriptive and inferential statistics, as well as content analysis for open-ended questions, were used to summarize findings. ResultsThirty-one facility administrators (representing thirty-two facilities) participated in the interviews. Six administrators had taken action and 18 were planning on taking action as a result of FARs. The majority found the four contextual areas addressed in FAR to be useful, meaningful, and understandable. They liked the comparisons made between data from years one and two and between their facility and other TREC study sites in their province. Twenty-two indicated that they would like to receive information on additional areas such as aggressive behaviours of residents and information sharing. Twenty-four administrators indicated that FARs contained enough information, while eight found FARs ‘too short’. Administrators who reported that the FAR contained enough information were more likely to take action within their facilities than administrators who reported that they needed more information. ConclusionsAlthough the FAR was brief, the presentation of the four contextual areas was relevant to the majority of administrators and prompted them to plan or to take action within their facility. <br /
scattering S wave from the data on the reaction
The results of the recent experiments on the reaction
performed at KEK, BNL, IHEP, and CERN are analyzed in detail. For the I=0
S wave phase shift and inelasticity a new set
of data is obtained. Difficulties emerging when using the physical solutions
for the S and D wave amplitudes extracted with the partial wave
analyses are discussed. Attention is drawn to the fact that, for the
invariant mass, m, above 1 GeV, the other solutions, in principle,
are found to be more preferred. For clarifying the situation and further
studying the resonance thorough experimental investigations of the
reaction in the m region near the threshold
are required.Comment: 17 pages, 5 figure
Study of beam-induced particle backgrounds at the LEP detectors
Synchrotron radiation photons and off-momentum electrons which contribute to backgrounds in the LEP experiments have been simulated. A multi-faceted background protection system has been designed and installed which permits the experiments to take data under very clean conditions. The backgrounds have been measured at LEP1 and are in good agreement with calculations. These simulations and studies have led to a design of enhanced background protection for LEP2 where the photon background is expected to be far more severe
On the precision of the theoretical predictions for pi pi scattering
In a recent paper, Pelaez and Yndurain evaluate some of the low energy
observables of pi pi scattering and obtain flat disagreement with our earlier
results. The authors work with unsubtracted dispersion relations, so that their
results are very sensitive to the poorly known high energy behaviour of the
scattering amplitude. They claim that the asymptotic representation we used is
incorrect and propose an alternative one. We repeat their calculations on the
basis of the standard, subtracted fixed-t dispersion relations, using their
asymptotics. The outcome fully confirms our earlier findings. Moreover, we show
that the Regge parametrization proposed by these authors for the region above
1.4 GeV violates crossing symmetry: Their ansatz is not consistent with the
behaviour observed at low energies.Comment: Added more material, mostly in Sects. 7, 8 and 9, in support of the
same conclusions. Latex, 28 pages, 3 figure
Using the RE-AIM framework to evaluate physical activity public health programs in MĂ©xico
Background: Physical activity (PA) public health programming has been widely used in Mexico; however, few studies have documented individual and organizational factors that might be used to evaluate their public health impact. The RE-AIM framework is an evaluation tool that examines individual and organizational factors of public health programs. The purpose of this study was to use the RE-AIM framework to determine the degree to which PA programs in Mexico reported individual and organizational factors and to investigate whether reporting differed by the program's funding source. Methods: Public health programs promoting PA were systematically identified during 2008-2013 and had to have an active program website. Initial searches produced 23 possible programs with 12 meeting inclusion criteria. A coding sheet was developed to capture behavioral, outcome and RE-AIM indicators from program websites. Results: In addition to targeting PA, five (42%) programs also targeted dietary habits and the most commonly reported outcome was change in body composition (58%). Programs reported an average of 11.1 (±3.9) RE-AIM indicator items (out of 27 total). On average, 45% reported reach indicators, 34% reported efficacy/effectiveness indicators, 60% reported adoption indicators, 40% reported implementation indicators, and 35% reported maintenance indicators. The proportion of RE-AIM indicators reported did not differ significantly for programs that were government supported (Mâ=â10, SDâ=â3.1) and programs that were partially or wholly privately or corporately supported (Mâ=â12.0, SDâ=â4.4). Conclusion: While reach and adoption of these programs were most commonly reported, there is a need for stronger evaluation of behavioral and health outcomes before the public health impact of these programs can be established. © 2015 Jauregui et al.; licensee BioMed Central
Meson-meson scattering within one loop Chiral Perturbation Theory and its unitarization
We present the complete one-loop calculation of all the two meson scattering
amplitudes within the framework of SU(3) Chiral Perturbation Theory, which
includes pions, kaons and the eta. In addition, we have unitarized these
amplitudes with the coupled channel Inverse Amplitude Method, which ensures
simultaneously the good low energy properties of Chiral Perturbation Theory and
unitarity. We show how this method provides a remarkable description of
meson-meson scattering data up to 1.2 GeV including the scattering lengths and
the generation of seven light resonances, which is consistent with previous
determination of the chiral parameters. Particular attention is paid to discuss
the differences and similarities of this work with previous analysis in the
literature.Comment: 20 pages, 5 figures. Comments on sigma, kappa and eta', as well as
some references added. Final version to appear in Phys.Rev.
\pi\pi, K\pi and \pi N potential scattering and a prediction of a narrow \sigma meson resonance
Low energy scattering and bound state properties of the \pi N, \pi\pi and
K\pi systems are studied as coupled channel problems using inversion potentials
of phase shift data. In a first step we apply the potential model to explain
recent measurements of pionic hydrogen shift and width. Secondly, predictions
of the model for pionium lifetime and shift confirm a well known and widely
used effective range expression. Thirdly, as extension of this confirmation, we
predict an unexpected medium effect of the pionium lifetime which shortens by
several orders of magnitude. The \sigma meson shows a narrow resonance
structure as a function of the medium modified mass with the implication of
being essentially energy independent. Similarly, we see this medium resonance
effect realized for the K\pi system. To support our findings we present also
results for the \rho meson and the \Delta(1232) resonance.Comment: 42 pages, 17 PS figures, REFTeX, epsfig.sty needed, submitted to
Phys. Re
Assessment of variation in the alberta context tool: the contribution of unit level contextual factors and specialty in Canadian pediatric acute care settings
Background: There are few validated measures of organizational context and none that we located are
parsimonious and address modifiable characteristics of context. The Alberta Context Tool (ACT) was developed to
meet this need. The instrument assesses 8 dimensions of context, which comprise 10 concepts. The purpose of
this paper is to report evidence to further the validity argument for ACT. The specific objectives of this paper are
to: (1) examine the extent to which the 10 ACT concepts discriminate between patient care units and (2) identify
variables that significantly contribute to between-unit variation for each of the 10 concepts.
Methods: 859 professional nurses (844 valid responses) working in medical, surgical and critical care units of 8
Canadian pediatric hospitals completed the ACT. A random intercept, fixed effects hierarchical linear modeling
(HLM) strategy was used to quantify and explain variance in the 10 ACT concepts to establish the ACTâs ability to
discriminate between units. We ran 40 models (a series of 4 models for each of the 10 concepts) in which we
systematically assessed the unique contribution (i.e., error variance reduction) of different variables to between-unit
variation. First, we constructed a null model in which we quantified the variance overall, in each of the concepts.
Then we controlled for the contribution of individual level variables (Model 1). In Model 2, we assessed the
contribution of practice specialty (medical, surgical, critical care) to variation since it was central to construction of
the sampling frame for the study. Finally, we assessed the contribution of additional unit level variables (Model 3).
Results: The null model (unadjusted baseline HLM model) established that there was significant variation between
units in each of the 10 ACT concepts (i.e., discrimination between units). When we controlled for individual
characteristics, significant variation in the 10 concepts remained. Assessment of the contribution of specialty to
between-unit variation enabled us to explain more variance (1.19% to 16.73%) in 6 of the 10 ACT concepts. Finally,
when we assessed the unique contribution of the unit level variables available to us, we were able to explain
additional variance (15.91% to 73.25%) in 7 of the 10 ACT concepts.
Conclusion: The findings reported here represent the third published argument for validity of the ACT and adds
to the evidence supporting its use to discriminate patient care units by all 10 contextual factors. We found
evidence of relationships between a variety of individual and unit-level variables that explained much of this
between-unit variation for each of the 10 ACT concepts. Future research will include examination of the
relationships between the ACTâs contextual factors and research utilization by nurses and ultimately the
relationships between context, research utilization, and outcomes for patients
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