12 research outputs found
Leukocyte surface biomarkers implicate deficits of innate immunity in sporadic Alzheimer\u27s disease
Introduction: Blood-based diagnostics and prognostics in sporadic Alzheimer\u27s disease (AD) are important for identifying at-risk individuals for therapeutic interventions. Methods: In three stages, a total of 34 leukocyte antigens were examined by flow cytometry immunophenotyping. Data were analyzed by logistic regression and receiver operating characteristic (ROC) analyses. Results: We identified leukocyte markers differentially expressed in the patients with AD. Pathway analysis revealed a complex network involving upregulation of complement inhibition and downregulation of cargo receptor activity and Aβ clearance. A proposed panel including four leukocyte markers – CD11c, CD59, CD91, and CD163 – predicts patients’ PET Aβ status with an area under the curve (AUC) of 0.93 (0.88 to 0.97). CD163 was the top performer in preclinical models. These findings have been validated in two independent cohorts. Conclusion: Our finding of changes on peripheral leukocyte surface antigens in AD implicates the deficit in innate immunity. Leukocyte-based biomarkers prove to be both sensitive and practical for AD screening and diagnosis
Landsat 9 Thermal Infrared Sensor 2 Architecture and Design
The Thermal Infrared Sensor 2 (TIRS-2) will fly aboard the Landsat 9 spacecraft and leverages the Thermal Infrared Sensor (TIRS) design currently flying on Landsat 8. TIRS-2 will provide similar science data as TIRS, but is not a buildto-print rebuild due to changes in requirements and improvements in absolute accuracy. The heritage TIRS design has been modified to reduce the influence of stray light and to add redundancy for higher reliability over a longer mission life. The TIRS-2 development context differs from the TIRS scenario, adding to the changes. The TIRS-2 team has also learned some lessons along the way
Hitomi (ASTRO-H) X-ray Astronomy Satellite
The Hitomi (ASTRO-H) mission is the sixth Japanese x-ray astronomy satellite developed by a large international collaboration, including Japan, USA, Canada, and Europe. The mission aimed to provide the highest energy resolution ever achieved at E > 2 keV, using a microcalorimeter instrument, and to cover a wide energy range spanning four decades in energy from soft x-rays to gamma rays. After a successful launch on February 17, 2016, the spacecraft lost its function on March 26, 2016, but the commissioning phase for about a month provided valuable information on the onboard instruments and the spacecraft system, including astrophysical results obtained from first light observations. The paper describes the Hitomi (ASTRO-H) mission, its capabilities, the initial operation, and the instruments/spacecraft performances confirmed during the commissioning operations for about a month
Landsat 9 TIRS-2 Architecture and Design
TIRS-2 will fly on the LandSat 9. Like TIRS on Landsat 8, TIRS-2 will produce radiometrically calibrated, geo-located thermal image data. USGS is responsible for operational code. TIRS-2 image data will have the same performance characteristics as that of TIRS on Landsat 8 except better in some cases
Equating the HBSC Family Affluence Scale across survey years: a method to account for item parameter drift using the Rasch model
Purpose To investigate the measurement invariance (MI) of the Family Affluence Scale (FAS) measured in the Health Behavior in School-aged Children (HBSC) survey, and to describe a method for equating the scale when MI is violated across survey years. Methods This study used a sample of 14,076 Norwegian and 17,365 Scottish adolescents from the 2002, 2006 and 2010 HBSC surveys to investigate the MI of the FAS across survey years. Violations of MI in the form of differential item functioning (DIF) due to item parameter drift (IPD) were modeled within the Rasch framework to ensure that the FAS scores from different survey years remain comparable. Results The results indicate that the FAS is upwardly biased due to IPD in the computer item across survey years in the Norwegian and Scottish samples. Ignoring IPD across survey years resulted in the conclusion that family affluence is increasing quite consistently in Norway and Scotland. However, the results show that a large part of the increase in the FAS scores can be attributed to bias in the FAS because of IPD across time. The increase in the FAS was more modest in Scotland and slightly negative in Norway once the DIF in the computer item was accounted for in this study. Conclusions When the comparison of family affluence is necessary over different HBSC survey years or when the longitudinal implications of family affluence are of interest, it is necessary to account for IPD in interpretation of changes in family affluence across time
In-orbit Operation of the Soft X-Ray Spectrometer Onboard the Hitomi Satellite
We summarize all of the in-orbit operations of the soft x-ray spectrometer (SXS) onboard the ASTRO-H (Hitomi) satellite. The satellite was launched on February 17, 2016, and the communication with the satellite ceased on March 26, 2016. The SXS was still in the commissioning phase, in which the set-ups were progressively changed. This paper is intended to serve as a concise reference of the events in orbit in order to properly interpret the SXS data taken during its short lifetime and as a test case for planning the in-orbit operation for future microcalorimeter missions
The ASTRO-H X-ray astronomy satellite
The joint JAXA/NASA ASTRO-H mission is the sixth in a series of highly
successful X-ray missions developed by the Institute of Space and Astronautical
Science (ISAS), with a planned launch in 2015. The ASTRO-H mission is equipped
with a suite of sensitive instruments with the highest energy resolution ever
achieved at E > 3 keV and a wide energy range spanning four decades in energy
from soft X-rays to gamma-rays. The simultaneous broad band pass, coupled with
the high spectral resolution of Delta E < 7 eV of the micro-calorimeter, will
enable a wide variety of important science themes to be pursued. ASTRO-H is
expected to provide breakthrough results in scientific areas as diverse as the
large-scale structure of the Universe and its evolution, the behavior of matter
in the gravitational strong field regime, the physical conditions in sites of
cosmic-ray acceleration, and the distribution of dark matter in galaxy clusters
at different redshifts.Comment: 24 pages, 18 figures, Proceedings of the SPIE Astronomical
Instrumentation "Space Telescopes and Instrumentation 2014: Ultraviolet to
Gamma Ray