603 research outputs found
End user development: Satisfaction with tools and satisfaction with applications
This study explored the relationship between end user developersâ perceptions of their applications and their perceptions of the tools used to create them. Satisfaction with a user developed application was found to be significantly correlated with satisfaction with the tool used to create the application. The role of experience in this relationship was also explored, and possible implications of the findings are discussed
The Nature of CO Emission from z~6 Quasars
We investigate the nature of molecular gas emission from z ~ 6 quasars via the commonly observed tracer of H2, carbon monoxide (CO). We achieve this by combining non-LTE radiative transfer calculations with merger-driven models of z ~ 6 quasar formation that arise naturally in Î cold dark matter structure formation simulations. Motivated by observational constraints, we consider four representative z ~ 6 quasars formed in the halo mass range ~1012-1013 Mâ from different merging histories. Our main results are as follows. We find that, owing to massive starbursts and funneling of dense gas into the nuclear regions of merging galaxies, the CO is highly excited during both the hierarchical buildup of the host galaxy and the quasar phase, and the CO flux density peaks between J = 5 and 8. The CO morphology of z ~ 6 quasars often exhibits multiple CO emission peaks which arise from molecular gas concentrations which have not yet fully coalesced. Both of these results are found to be consistent with the sole CO detection at z ~ 6, in quasar J1148+5251. Quasars which form at z ~ 6 display a large range of sight line-dependent line widths. The sight line dependencies are such that the narrowest line widths are when the rotating molecular gas associated with the quasar is viewed face-on (when the LB is largest) and broadest when the quasar is seen edge-on (and the LB is lowest). Thus, we find that for all models selection effects exist such that quasars selected for optical luminosity are preferentially seen to be face-on which may result in CO detections of optically luminous quasars at z ~ 6 having line widths narrower than the median. The mean sight line-averaged line width is found to be reflective of the circular velocity of the host halo and thus scales with halo mass. For example, the mean line width for the ~1012 Mâ halo is Ï ~ 300 km sâ1, while the median for the ~1013 Mâ quasar host is Ï ~ 650 km sâ1. Depending on the host halo mass, approximately 2%-10% of sight lines in our modeled quasars are found to have narrow line widths compatible with observations of J1148+5251. When considering the aforementioned selection effects, these percentages increase to 10%-25% for quasars selected for optical luminosity. When accounting for both temporal evolution of CO line widths in galaxies, as well as the redshift evolution of halo circular velocities, these models can self-consistently account for the observed line widths of both submillimeter galaxies and quasars at z ~ 2. Finally, we find that the dynamical mass derived from the mean sight line-averaged line widths provide a good estimate of the total mass and allow for a massive molecular reservoir, supermassive black hole, and stellar bulge, consistent with the local MBH-Mbul relation
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Industrial demand side management status report: Synopsis
Industrial demand side management (DSM) programs, though not as developed or widely implemented as residential and commercial programs, hold the promise of significant energy savings-savings that will benefit industrial firms, utilities and the environment. This paper is a synopsis of a larger research report, Industrial Demand Side Management. A Status Report, prepared for the US Department of Energy. The report provides an overview of and rationale for DSM programs. Benefits and barriers are described, and data from the Manufacturing Energy Consumption Survey are used to estimate potential electricity savings from industrial energy efficiency measures. Overcoming difficulties to effective program implementation is worthwhile, since rough estimates indicate a substantial potential for electricity savings. The report categorizes types of DSM programs, presents several examples of each type, and explores elements of successful programs. Two in-depth case studies (of Boise Cascade and of Eli Lilly and Company) illustrate two types of effective DSM programs. Interviews with staff from state public utility commissions indicate the current thinking about the status and future of industrial DSM programs. Finally, the research report also includes a comprehensive bibliography, a description of technical assistance programs, and an example of a methodology for evaluating potential or actual savings from projects
Gastroesophageal reflux and antacid therapy in IPF: analysis from the Australia IPF Registry
BACKGROUND AND OBJECTIVE:Gastroesophageal reflux disease (GORD) is highly prevalent in idiopathic pulmonary fibrosis (IPF) and may play a role in its pathogenesis. Recent IPF treatment guidelines suggest that all patients with IPF be considered for antacid therapy. However, emerging evidence suggests that antacid therapy does not improve IPF patient outcomes and may increase the risk of pulmonary infection. METHODS:Using prospectively collected data from the Australian IPF Registry including use of antacid therapy, GORD diagnosis and GORD symptoms, the relationship of these GORD variables to survival and disease progression was assessed. The severity of GORD symptoms using the frequency scale for symptoms of GORD (FSSG) and its relationships to outcomes was also assessed for the first time in an IPF cohort. RESULTS:Five hundred eighty-seven (86%) of the 684 patients in the Australian IPF Registry were eligible for inclusion. Patients were mostly male (69%), aged 71.0â±â8.5âyears with moderate disease (FVC 81.7â±â21.5%; DLco 48.5â±â16.4%). Most patients were taking antacids (n =â384; 65%), though fewer had a diagnosis of GORD (n =â243, 41.4%) and typical GORD symptoms were even less common (n =â171, 29.1%). The mean FSSG score was 8.39â±â7.45 with 43% (n =â251) having a scoreâ>â8. Overall, there was no difference in survival or disease progression, regardless of antacid treatment, GORD diagnosis or GORD symptoms. CONCLUSIONS:Neither the use of antacid therapy nor the presence of GORD symptoms affects longer term outcomes in IPF patients. This contributes to the increasing evidence that antacid therapy may not be beneficial in IPF patients and that GORD directed therapy should be considered on an individual basis to treat the symptoms of reflux.Helen E. Jo, Tamera J. Corte, Ian Glaspole, Christopher Grainge, Peter M. A. Hopkins ... Peter A. Bampton ... et al
Disease progression in idiopathic pulmonary fibrosis with mild physiological impairment: analysis from the Australian IPF registry
BACKGROUND:Idiopathic pulmonary fibrosis (IPF) is a progressive and fatal fibrosing lung disease of unknown cause. The advent of anti-fibrotic medications known to slow disease progression has revolutionised IPF management in recent years. However, little is known about the natural history of IPF patients with mild physiological impairment. We aimed to assess the natural history of these patients using data from the Australian IPF Registry (AIPFR). METHODS:Using our cohort of real-world IPF patients, we compared FVC criteria for mild physiological impairment (FVCââ„â80%) against other proposed criteria: DLcoââ„â55%; CPI â€40 and GAP stage 1 with regards agreement in classification and relationship with disease outcomes. Within the mild cohort (FVCââ„â80%), we also explored markers associated with poorer prognosis at 12 months. RESULTS:Of the 416 AIPFR patients (mean age 70.4 years, 70% male), 216 (52%) were classified as 'mild' using FVCââ„â80%. There was only modest agreement between FVC and DLco (kâ=â0.30), with better agreement with GAP (kâ=â0.50) and CPI (kâ=â0.48). Patients who were mild had longer survival, regardless of how mild physiologic impairment was defined. There was, however, no difference in the annual decline in FVC% predicted between mild and moderate-severe groups (for all proposed criteria). For patients with mild impairment (n =â216, FVCââ„â80%), the strongest predictor of outcomes at 12 months was oxygen desaturation on a 6 min walk test. CONCLUSION:IPF patients with mild physiological impairment have better survival than patients with moderate-severe disease. Their overall rate of disease progression however, is comparable, suggesting that they are simply at different points in the natural history of IPF disease.Helen E. Jo, Ian Glaspole, Yuben Moodley, Sally Chapman, Samantha Ellis ... Reynolds ... Paul N. Reynolds ... et al
Shrinking a large dataset to identify variables associated with increased risk of Plasmodium falciparum infection in Western Kenya
Large datasets are often not amenable to analysis using traditional single-step approaches. Here, our general objective was to apply imputation techniques, principal component analysis (PCA), elastic net and generalized linear models to a large dataset in a systematic approach to extract the most meaningful predictors for a health outcome. We extracted predictors for Plasmodium falciparum infection, from a large covariate dataset while facing limited numbers of observations, using data from the People, Animals, and their Zoonoses (PAZ) project to demonstrate these techniques: data collected from 415 homesteads in western Kenya, contained over 1500 variables that describe the health, environment, and social factors of the humans, livestock, and the homesteads in which they reside. The wide, sparse dataset was simplified to 42 predictors of P. falciparum malaria infection and wealth rankings were produced for all homesteads. The 42 predictors make biological sense and are supported by previous studies. This systematic data-mining approach we used would make many large datasets more manageable and informative for decision-making processes and health policy prioritization
Measurement of the Bottom-Strange Meson Mixing Phase in the Full CDF Data Set
We report a measurement of the bottom-strange meson mixing phase \beta_s
using the time evolution of B0_s -> J/\psi (->\mu+\mu-) \phi (-> K+ K-) decays
in which the quark-flavor content of the bottom-strange meson is identified at
production. This measurement uses the full data set of proton-antiproton
collisions at sqrt(s)= 1.96 TeV collected by the Collider Detector experiment
at the Fermilab Tevatron, corresponding to 9.6 fb-1 of integrated luminosity.
We report confidence regions in the two-dimensional space of \beta_s and the
B0_s decay-width difference \Delta\Gamma_s, and measure \beta_s in [-\pi/2,
-1.51] U [-0.06, 0.30] U [1.26, \pi/2] at the 68% confidence level, in
agreement with the standard model expectation. Assuming the standard model
value of \beta_s, we also determine \Delta\Gamma_s = 0.068 +- 0.026 (stat) +-
0.009 (syst) ps-1 and the mean B0_s lifetime, \tau_s = 1.528 +- 0.019 (stat) +-
0.009 (syst) ps, which are consistent and competitive with determinations by
other experiments.Comment: 8 pages, 2 figures, Phys. Rev. Lett 109, 171802 (2012
Models of peer support to remediate post-intensive care syndrome: A report developed by the SCCM Thrive International Peer Support Collaborative
Objective: Patients and caregivers can experience a range of physical, psychological, and
cognitive problems following critical care discharge. The use of peer support has been
proposed as an innovative support mechanism.
Design: We sought to identify technical, safety and procedural aspects of existing
operational models of peer support, among the Society of Critical Care Medicine Thrive Peer
Support Collaborative. We also sought to categorize key distinctions between these models
and elucidate barriers and facilitators to implementation.
Subjects: 17 Thrive sites from the USA, UK, and Australia were represented by a range of
healthcare professionals.
Interventions: Via an iterative process of in-person and email/conference calls, members
of the Collaborative, defined the key areas on which peer support models could be defined
and compared; collected detailed self-reports from all sites; reviewed the information and
identified clusters of models. Barriers and challenges to implementation of peer support
models were also documented.
Results: Within the Thrive Collaborative, six general models of peer support were identified:
Community based, Psychologist-led outpatient, Models based within ICU follow-up clinics,
Online, Groups based within ICU and Peer mentor models. The most common barriers to
implementation were: recruitment to groups, personnel input and training: sustainability
and funding, risk management and measuring success.
Conclusion: A number of different models of peer support are currently being developed
to help patients and families recover and grow in the post-critical care setting
Search for the standard model Higgs boson decaying into two photons in pp collisions at sqrt(s)=7 TeV
A search for a Higgs boson decaying into two photons is described. The
analysis is performed using a dataset recorded by the CMS experiment at the LHC
from pp collisions at a centre-of-mass energy of 7 TeV, which corresponds to an
integrated luminosity of 4.8 inverse femtobarns. Limits are set on the cross
section of the standard model Higgs boson decaying to two photons. The expected
exclusion limit at 95% confidence level is between 1.4 and 2.4 times the
standard model cross section in the mass range between 110 and 150 GeV. The
analysis of the data excludes, at 95% confidence level, the standard model
Higgs boson decaying into two photons in the mass range 128 to 132 GeV. The
largest excess of events above the expected standard model background is
observed for a Higgs boson mass hypothesis of 124 GeV with a local significance
of 3.1 sigma. The global significance of observing an excess with a local
significance greater than 3.1 sigma anywhere in the search range 110-150 GeV is
estimated to be 1.8 sigma. More data are required to ascertain the origin of
this excess.Comment: Submitted to Physics Letters
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