Report of the direct infrared sensors panel

The direct infrared sensors panel considered a wide range of options for technologies relevant to the science goals of the Astrotech 21 mission set. Among the technologies assessed are: large format arrays; photon counting detectors; higher temperature 1 to 10 micro-m arrays; impurity band conduction (IBC) or blocked impurity band (BIB) detectors; readout electronics; and adapting the Space Infrared Telescope Facility and Hubble Space Telescope. Detailed development plans were presented for each of these technology areas

Cost-effectiveness of eplerenone in patients with systolic heart failure and mild symptoms

Aim In the Eplerenone in Mild Patients Hospitalization and Survival Study in Heart Failure (EMPHASIS-HF), aldosterone blockade with eplerenone decreased mortality and hospitalisation in patients with mild symptoms (New York Heart Association class II) and chronic systolic heart failure (HF). The present study evaluated the cost-effectiveness of eplerenone in the treatment of these patients in the UK and Spain.<p></p> Methods and results Results from the EMPHASIS-HF trial were used to develop a discrete-event simulation model estimating lifetime direct costs and effects (life years and quality-adjusted life years (QALYs) gained) of the addition of eplerenone to standard care among patients with chronic systolic HF and mild symptoms. Eplerenone plus standard care compared with standard care alone increased lifetime direct costs per patient by £4284 for the UK and €7358 for Spain, with additional quality-adjusted life expectancy of 1.22 QALYs for the UK and 1.33 QALYs for Spain. Mean lifetime costs were £3520 per QALY in the UK and €5532 per QALY in Spain. Probabilistic sensitivity analysis suggested a 100% likelihood of eplerenone being regarded as cost-effective at a willingness-to-pay threshold of £20 000 per QALY (UK) or €30 000 per QALY (Spain).<p></p> Conclusions By currently accepted standards of value for money, the addition of eplerenone to optimal medical therapy for patients with chronic systolic HF and mild symptoms is likely to be cost-effective.<p></p&gt

Performance of a Magnesium-Rich Primer on Pretreated AA2024-T351 in Full Immersion: a Galvanic Throwing Power Investigation Using a Scanning Vibrating Electrode Technique

The scanning vibrating electrode technique (SVET) was employed to examine the effect of ‘galvanic throwing power’ and the distance over which a Mg-rich primer (MgRP) provided sacrificial anode-based cathodic protection to AA2024-T351. Three systems were investigated in full immersion conditions where the same MgRP was used with three different pretreatments: Non-film forming (NFF), trivalent chromium pretreatment (TCP) and anodization with a chromate seal (ACS). Experiments were conducted with two coating/defect area ratios and three parameters were monitored: 1) the maximum peak height of local anodes, inferring the location and intensity of pits, 2) the current density profile at the coating/defect interface (CDI) region and 3) total integrated anodic and cathodic current density values of defined areas in the defect region moving progressively away from the CDI. The NFF-based system was shown to provide the superior galvanic throwing power and a quasi-steady-state galvanic current distribution was detected in the defect region adjacent to the CDI indicating enhanced cathodic activity in response to the MgRP. High resistance between the MgRP and the substrate, due to the thickness of the pretreatment layer, appeared to mediate galvanic interactions in the case of TCP and ACS-based systems

Altered cellular infiltration and cytokine levels during early Mycobacterium tuberculosis sigC mutant infection are associated with late-stage disease attenuation and milder immunopathology in mice

<p>Abstract</p> <p>Background</p> <p>Mouse virulence assessments of certain <it>Mycobacterium tuberculosis </it>mutants have revealed an immunopathology defect in which high tissue CFU counts are observed but the tissue pathology and lethality are reduced. <it>M. tuberculosis </it>mutants which grow and persist in the mouse lungs, but have attenuated disease progression, have the immunopathology (<it>imp</it>) phenotype. The antigenic properties of these strains may alter the progression of disease due to a reduction in host immune cell recruitment to the lungs resulting in disease attenuation and prolonged host survival.</p> <p>Results</p> <p>In this study we focused on the mouse immune response to one such mutant; the <it>M. tuberculosis </it>Δ<it>sigC </it>mutant. Aerosol infection of DBA/2 and SCID mice with the <it>M. tuberculosis </it>Δ<it>sigC </it>mutant, complemented mutant and wild type strain showed proliferation of mutant bacilli in mouse lungs, but with decreased inflammation and mortality in DBA/2 mice. SCID mice shared the same phenotype as the DBA/2 mice in response to the Δ<it>sigC </it>mutant, however, they succumbed to the infection faster. Bronchoalveolar lavage (BAL) fluid analysis revealed elevated numbers of infiltrating neutrophils in the lungs of mice infected with wild type and complemented Δ<it>sigC </it>mutant strains but not in mice infected with the Δ<it>sigC </it>mutant. In addition, DBA/2 mice infected with the Δ<it>sigC </it>mutant had reduced levels of TNF-α, IL-1β, IL-6 and IFN-γ in the lungs. Similarly, there was a reduction in proinflammatory cytokines in the lungs of SCID mice. In contrast to the mouse model, the Δ<it>sigC </it>mutant had reduced initial growth in guinea pig lungs. A possible mechanism of attenuation in the Δ<it>sigC </it>mutant may be a reduction in neutrophilic-influx in the alveolar spaces of the lungs, and decreased proinflammatory cytokine secretion. In contrast to mouse data, the <it>M. tuberculosis </it>Δ<it>sigC </it>mutant proliferates slowly in guinea pig lungs, a setting characterized by caseating necrosis.</p> <p>Conclusion</p> <p>Our observations suggest that the immunopathology phenotype is associated with the inability to trigger a strong early immune response, resulting in disease attenuation. While macrophages and T cells have been shown to be important in containing <it>M. tuberculosis </it>disease our study has shown that neutrophils may also play an important role in the containment of this organism.</p

NT-proBNP by Itself Predicts Death and Cardiovascular Events in High-Risk Patients With Type 2 Diabetes Mellitus

BACKGROUND: NT-proBNP (N-terminal pro-B-type natriuretic peptide) improves the discriminatory ability of risk-prediction models in type 2 diabetes mellitus (T2DM) but is not yet used in clinical practice. We assessed the discriminatory strength of NT-proBNP by itself for death and cardiovascular events in high-risk patients with T2DM. METHODS AND RESULTS: Cox proportional hazards were used to create a base model formed by 20 variables. The discriminatory ability of the base model was compared with that of NT-proBNP alone and with NT-proBNP added, using C-statistics. We studied 5509 patients (with complete data) of 8561 patients with T2DM and cardiovascular and/or chronic kidney disease who were enrolled in the ALTITUDE (Aliskiren in Type 2 Diabetes Using Cardiorenal Endpoints) trial. During a median 2.6-year follow-up period, 469 patients died and 768 had a cardiovascular composite outcome (cardiovascular death, resuscitated cardiac arrest, nonfatal myocardial infarction, stroke, or heart failure hospitalization). NT-proBNP alone was as discriminatory as the base model for predicting death (C-statistic, 0.745 versus 0.744, P=0.95) and the cardiovascular composite outcome (C-statistic, 0.723 versus 0.731, P=0.37). When NT-proBNP was added, it increased the predictive ability of the base model for death (C-statistic, 0.779 versus 0.744, P<0.001) and for cardiovascular composite outcome (C-statistic, 0.763 versus 0.731, P<0.001). CONCLUSIONS: In high-risk patients with T2DM, NT-proBNP by itself demonstrated discriminatory ability similar to a multivariable model in predicting both death and cardiovascular events and should be considered for risk stratification. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT00549757

Validation of Up-the-Ramp Sampling with Cosmic Ray Rejection on IR Detectors

We examine cosmic ray rejection methodology on data collected from InSb and Si:As detectors. The application of an Up-the-Ramp sampling technique with cosmic ray identification and mitigation is the focus of this study. This technique is valuable for space-based observatories which are exposed to high-radiation environments. We validate the Up-the-Ramp approach on radiation-test data sets with InSb and Si:As detectors which were generated for SIRTF. The Up-the-Ramp sampling method studied in this paper is over 99.9% effective at removing cosmic rays and preserves the structure and photometric quality of the image to well within the measurement error.Comment: 30 pages, 13 figures. Accepted for publication in the PASP, 25 October 200

Defining Accelerometer Thresholds for Activity Intensities in Adolescent Girls

Purpose - To derive a regression equation that estimates metabolic equivalent (MET) from accelerometer counts, and to define thresholds of accelerometer counts that can be used to delineate sedentary, light, moderate, and vigorous activity. Methods - Seventy-four healthy 8th grade girls, age 13-14 yr, were recruited from urban areas of Baltimore, MD, Minneapolis/St. Paul, MN, and Columbia, SC, to participate in the study. Accelerometer and oxygen consumption (VO2) data for 10 activities that varied in intensity from sedentary (e.g., TV watching) to vigorous (e.g., running) were collected. While performing these activities, the girls wore two accelerometers, a heart rate monitor and a Cosmed K4b2 portable metabolic unit for measurement of VO2. A random-coefficients model was used to estimate the relationship between accelerometer counts and VO2. Activity thresholds were defined by minimizing the false positive and false negative classifications. Results - The activities provided a wide range in VO2 (3-36 mL·kg-1·min-1) with a correspondingly wide range in accelerometer counts (1-3928 counts·30 s-1). The regression line for MET score versus counts was MET=2.01+0.00171 (counts·30 s-1) (mixed model R2=0.84, SEE=1.36). A threshold of 1500 counts·30 s-1 defined the lower end of the moderate intensity (~4.6 METs) range of physical activity. That cutpoint distinguished between slow and brisk walking, and gave the lowest number of false positive and false negative classifications. The threshold ranges for sedentary, light, moderate, and vigorous physical activity were found to be 0-50, 51-1499, 1500-2600, and \u3e2600 counts·30 s-1, respectively. Conclusion - The developed equation and these activity thresholds can be used for prediction of MET score from accelerometer counts and participation in various intensities of physical activity in adolescent girls

Nucleon Polarizabilities from Deuteron Compton Scattering within a Green's-Function Hybrid Approach

We examine elastic Compton scattering from the deuteron for photon energies ranging from zero to 100 MeV, using state-of-the-art deuteron wave functions and NN-potentials. Nucleon-nucleon rescattering between emission and absorption of the two photons is treated by Green's functions in order to ensure gauge invariance and the correct Thomson limit. With this Green's-function hybrid approach, we fulfill the low-energy theorem of deuteron Compton scattering and there is no significant dependence on the deuteron wave function used. Concerning the nucleon structure, we use Chiral Effective Field Theory with explicit \Delta(1232) degrees of freedom within the Small Scale Expansion up to leading-one-loop order. Agreement with available data is good at all energies. Our 2-parameter fit to all elastic $\gamma d$ data leads to values for the static isoscalar dipole polarizabilities which are in excellent agreement with the isoscalar Baldin sum rule. Taking this value as additional input, we find \alpha_E^s= (11.3+-0.7(stat)+-0.6(Baldin)) x 10^{-4} fm^3 and \beta_M^s = (3.2-+0.7(stat)+-0.6(Baldin)) x 10^{-4} fm^3 and conclude by comparison to the proton numbers that neutron and proton polarizabilities are essentially the same.Comment: 47 pages LaTeX2e with 20 figures in 59 .eps files, using graphicx. Minor modifications; extended discussion of theoretical uncertainties of polarisabilities extraction. Version accepted for publication in EPJ