22 research outputs found
The Sydney-AAO Multi-object Integral field spectrograph (SAMI)
We demonstrate a novel technology that combines the power of the multi-object
spectrograph with the spatial multiplex advantage of an integral field
spectrograph (IFS). The Sydney-AAO Multi-object IFS (SAMI) is a prototype
wide-field system at the Anglo-Australian Telescope (AAT) that allows 13
imaging fibre bundles ("hexabundles") to be deployed over a 1-degree diameter
field of view. Each hexabundle comprises 61 lightly-fused multimode fibres with
reduced cladding and yields a 75 percent filling factor. Each fibre core
diameter subtends 1.6 arcseconds on the sky and each hexabundle has a field of
view of 15 arcseconds diameter. The fibres are fed to the flexible AAOmega
double-beam spectrograph, which can be used at a range of spectral resolutions
(R=lambda/delta(lambda) ~ 1700-13000) over the optical spectrum (3700-9500A).
We present the first spectroscopic results obtained with SAMI for a sample of
galaxies at z~0.05. We discuss the prospects of implementing hexabundles at a
much higher multiplex over wider fields of view in order to carry out
spatially--resolved spectroscopic surveys of 10^4 to 10^5 galaxies.Comment: 24 pages, 16 figures. Accepted by MNRA
GNOSIS: The first instrument to use fiber bragg gratings for OH suppression
The near-infrared is an important part of the spectrum in astronomy, especially in cosmology because the light from objects in the early universe is redshifted to these wavelengths. However, deep near-infrared observations are extremely difficult to makeThe GNOSIS team acknowledges funding by ARC LIEF
grant LE100100164. C.Q.T. gratefully acknowledges support by the National
Science Foundation Graduate Research Fellowship under grant
No. DGE-1035963
The SAMI Galaxy Survey : data release one with emission-line physics value-added products
SAMI DR1 data products available from http://datacentral.aao.gov.au/asvo/surveys/sami/We present the first major release of data from the SAMI Galaxy Survey. This data release focuses on the emission-line physics of galaxies. Data Release One includes data for 772 galaxies, about 20% of the full survey. Galaxies included have the redshift range 0.004 < z < 0.092, a large massrange (7.6 < log M∗/M⊙ < 11.6), and star-formation rates of ∼10−4 to ∼101 M⊙yr−1. For each galaxy, we include two spectral cubes and a set of spatially resolved 2D maps: single- and multi-component emission-line fits (with dust extinction corrections for strong lines), local dust extinction and star-formation rate. Calibration of the fibre throughputs, fluxes and differential-atmospheric-refraction has been improved over the Early Data Release. The data have average spatial resolution of 2.16 arcsec (FWHM) over the 15 arcsec diameter field of view and spectral (kinematic) resolution R= 4263 (σ= 30 km s−1) around Hα. The relative flux calibration is better than 5% and absolute flux calibration better than ±0.22 mag, with the latter estimate limited by galaxy photometry. The data are presented online through the Australian Astronomical Observatory’s Data Central.Publisher PDFPeer reviewe
Discordance between change in estimated MET during supervised exercise training and change in peak oxygen uptake
Introduction: Metabolic equivalent of task METs), estimatedfrom exercise trainingworkloads during supervised exercisetraining (SET), are an accepted outcome measurefor cardiac rehabilitation programs. However, it is not clear how well change in estimatedMETs during SET correlate to changes in exercise capacity measured during a symptomlimited from an exercise test.Purpose: Compare the change inMETs estimated from SET workloads to exercise capacity based on measured peak oxygen uptake (VO2) and the 6 minute walk test distance(6MWD).Design: Secondary analysis of the HF-ACTION trial.Methods: Among subjects with HFrEF (ejection fraction =40%) randomized to exercisetraining, we identified 357 (age= 59±11 years; 30% women; 64% white) who performedboth a cardiopulmonary exercise test (CPET) on a treadmill for exercise duration and peakVO2, and a 6 minute walk test at baseline and 3 months, and completed =12 SET visitsduring the same 3 month period. Estimated METs during SET were calculated from treadmill training, with baseline representing the mean of SET visits 2 and 3, and at 3 monthfollow up the mean of the last 2 SET visits. Linear regression was used to determine thePearson correlation and standard error of estimate (SEE) between % change from baselineto 3 months in estimated METs during SET to % change in (1) peak VO2 and, (2) exerciseduration during the CPET, and (3) 6MWD.Results: At baseline the mean±sd estimated METs, peak VO2, exercise duration, and6MWD were 3.0±0.9 METs, 15.4±4.5 mL/kg/min, 10.5±3.7 min, and 384±90 m, respectively. At 3 months each of these increased 29±29%, 8±18%, 28±37%, and 10±32%,respectively (all increases were \u3c 0.05). The correlation and SEE between % change inSET METs and % change in peak VO2 were r= 0.124 (p= 0.02) and 18%, respectively. For% change in SET METs and % change in exercise duration, r= 0.237 (
Real world experience with regadenoson spect myocardial perfusion imaging: Patient characteristics, safety, and impact of results on clinical management
Cardiopulmonary exercise measures of men and women with HFrEF differ in their relationship to prognosis: The Henry Ford Hospital Cardiopulmonary Exercise Testing (FIT-CPX) project
BACKGROUND: This study evaluated if different prognostic characteristics exist for peak oxygen consumption (VO2), percent predicted peak VO2 (ppVO2), and the slope of the change in minute ventilation to volume of carbon dioxide produced (VE-VCO2) slope between men and women with heart failure and reduced ejection fraction (HFrEF).
METHODS: Analysis of the Henry Ford Hospital Cardiopulmonary Exercise Testing database (n = 1085; 33% women, 55% black) of individuals with HFrEF who completed a physician-referred cardiopulmonary exercise testing (CPX) between 1997 and 2010. Primary outcome was a composite of all-cause death, left ventricular assist device placement, and orthotopic heart transplant . Logistic and Cox regressions were performed and Kaplan-Meier survival curves were developed to describe relationships of the CPX variables and the composite outcome within and between men and women.
RESULTS: All patients were followed-up for a minimum of 5 years, during which there were 643 combined events (62%; 499 deaths, 64 left ventricular assist device implants, 80 orthotopic heart transplant). Each CPX variable was significantly related to event-free survival among both men and women. Log-rank assessment of Kaplan-Meier curves noted survival differences for peak VO2 and VE-VCO2 slope (p ≤ .002), but not ppVO2 (P = .32), between men and women.
CONCLUSIONS: Prognostic values for peak VO2 and the VE-VCO2 slope might be considered separately for men and women, whereas the ppVO2 value corresponding to 1- and 3-year survival rates may not be different between the sexes
Challenges with Percent Predicted Maximal V˙O2 in Patients with Heart Failure
PURPOSE: This study aimed to describe the influence of different equations to predict maximal oxygen uptake (MV˙O2) on the percent predicted MV˙O2 (ppMV˙O2) and the resultant categorization of patients with heart failure with reduced ejection fraction into high or low risk.
METHODS: In this retrospective cohort study, ppMV˙O2 was calculated using six different equations to predict MV˙O2 among 1168 patients with heart failure with reduced ejection fraction (33% women). Repeated-measures ANOVA was used to compare within-subject differences in mean ppMV˙O2 between the prediction equations. Cochrane\u27s Q test was used to compare the within-subject difference in the proportion of patients with ppMV˙O2 of
RESULTS: The ppMV˙O2 varied significantly (P \u3c 0.001) between the MV˙O2 prediction equations, with mean (10th, 90th percentile) ppMV˙O2 ranging from 39% (25%, 54%) to 60% (39%, 83%) in men and 37% (24%, 49%) to 70% (47%, 94%) in women. Significant variation (P \u3c 0.001) was also observed between prediction equations for the proportion of patients with ppMV˙O2 of
CONCLUSIONS: Statistically significant and clinically meaningful variations in the ppMV˙O2 are observed on the basis of the reference equation used to predict MV˙O2. Future writing committees should specify the preferred reference equation when identifying a ppMV˙O2 criterion in guideline statements
Challenges with percent predicted maximal VO2 in patients with heart failure
PURPOSE: This study aimed to describe the influence of different equations to predict maximal oxygen uptake (MV˙O2) on the percent predicted MV˙O2 (ppMV˙O2) and the resultant categorization of patients with heart failure with reduced ejection fraction into high or low risk.
METHODS: In this retrospective cohort study, ppMV˙O2 was calculated using six different equations to predict MV˙O2 among 1168 patients with heart failure with reduced ejection fraction (33% women). Repeated-measures ANOVA was used to compare within-subject differences in mean ppMV˙O2 between the prediction equations. Cochrane\u27s Q test was used to compare the within-subject difference in the proportion of patients with ppMV˙O2 of
RESULTS: The ppMV˙O2 varied significantly (P \u3c 0.001) between the MV˙O2 prediction equations, with mean (10th, 90th percentile) ppMV˙O2 ranging from 39% (25%, 54%) to 60% (39%, 83%) in men and 37% (24%, 49%) to 70% (47%, 94%) in women. Significant variation (P \u3c 0.001) was also observed between prediction equations for the proportion of patients with ppMV˙O2 of
CONCLUSIONS: Statistically significant and clinically meaningful variations in the ppMV˙O2 are observed on the basis of the reference equation used to predict MV˙O2. Future writing committees should specify the preferred reference equation when identifying a ppMV˙O2 criterion in guideline statements
Effects of the HEART camp intervention on adherence to exercise in patients with heart failure
Background: Patients with heart failure (HF) have poor adherence to the recommended guidelines of30 minutes of moderate intensity exercise five days per week. The importance of adherence to exercise is underscored by recent data showing that lack ofadherence to recommended exercise leads toincreased risk for mortality and HF readmission. Thepurpose of this randomized controlled trial was toevaluate the effect of the HEART Camp (HC) protocol (multi-component intervention) on long-term adherence to exercise. Hypothesis: Subjects in theHEART Camp (HC) intervention group will have better adherence to exercise than the enhanced usual care (EUC) group over time (6, 12 and 18 months). Methods: A prospective randomized two-group (HC and EUC) repeated measures experimental design was used. Both groups received access to theexercise facility and 9 exercise training sessions in a 3-week run-in period. Group educational sessions and an exercise coach provided the interventioncomponents (knowl-edge, attitudes, self-efficacy, behavioral self-management skills and social support). Adherence (defined as 80% of therecommended 150 minutes of exercise) was mea-sured by an exercise diary with heart rate monitor validation of self-report. Results: The sample consisted of 191 subjects with a mean age of 60.9 + 11.4 years; 53.9% were male; EF was 39.9 + 13.1%; 54.5% were NYHA Class II and 36.6% were Class III; 53.4% were Caucasian and 45.5% were African-American. Chi-square analysis of adherence data showed no significant group differences at 6 months (P=.443). Both 12 and 18-month adherence in the HC group (42 and 35.2% respectively) were significantly higher (P \u3c.05) than the EUC group (27.8 and 19.3% respectively). See Fig. 1. An analysis of potential moderators of the intervention showed no significance for age, gender, race, marital status, or NYHA Class. Moderator effects were found for BMI with the HC intervention showing efficacy across thelevels of BMI while higher BMI in the EUC had lower adherence levels. The HC intervention improved adherence in subjects with higher EF while adherence in the EUC group was worse with higher EF Conclusions: The multi-component HC interventionsignificantly improved exercise adherence at 12 and 18 months. Providing subjects with access and 9 sessions of training improved short-term adherencein the EUC group
Clinical experience with regadenoson SPECT myocardial perfusion imaging: insights into patient characteristics, safety, and impact of results on clinical management
The Henry Ford Hospital (HFH) regadenoson (REG) registry includes patients with a variety of comorbidities allowing for the evaluation of outcomes in a large, unselected population. Using a database of electronic medical records and nuclear cardiology reports, patients aged \u3e 18 years who underwent REG-facilitated single-photon emission computed tomography (SPECT) testing at HFH between January 2009 and August 2012 were identified. The primary objective was to describe the clinical and demographic characteristics of patients who had undergone REG only vs REG WALK (REG + low-level exercise) SPECT. A total of 2104 patients were included in the analysis (mean age 65.3 years; 50% women; 51% African American, 43% Caucasian). For the REG only (n = 1318) and REG WALK (n = 786) cohorts, SPECT was abnormal in 37% of patients (REG only, 39%; REG WALK, 34%; P \u3c 0.01). No differences in diagnostic modalities or interventions in 90 days after SPECT were observed. Immediate safety analysis showed no deaths 48 h after REG SPECT testing. Although they guide invasive therapy, abnormal scans do not automatically lead to invasive testing. This demonstrates the focus on initial medical management, which reflects the existing evidence of initial goal-directed medical management of stable coronary disease