31,077 research outputs found
Longitudinal multivariate tensor- and searchlight-based morphometry using permutation testing
Tensor based morphometry [1] was used to detect
statistically significant regions of neuroanatomical
change over time in a comparison between 36 probable
Alzheimer's Disease patients and 20 age- and sexmatched
controls. Baseline and twelve-month repeat
Magnetic Resonance images underwent tied spatial
normalisation [10] and longitudinal high-dimensional
warps were then estimated. Analyses involved univariate
and multivariate data derived from the longitudinal
deformation fields. The most prominent findings were
expansion of the fluid spaces, and contraction of the
hippocampus and temporal region. Multivariate measures
were notably more powerful, and have the potential to
identify patterns of morphometric difference that would
be overlooked by conventional mass-univariate analysis
Nu sub 1 plus nu sub 3 combination band of SO2
The infrared-active vibration-rotation combination band nu sub 1 + nu sub 3 of sulfur dioxide was measured with moderately high spectral resolution. Quantum number identifications of spectral lines were made by comparison with theoretically computed spectra which include the effects of centrifugal distortion. Relative line intensities were also calculated. The band center for nu sub 1 + nu sub 3 was determined to be 2499.60 + or - 0.10/cm
Fundamental bands of S(32)O2(16)
The infrared-active vibration-rotation fundamentals of sulfur dioxide were measured with moderately high spectral resolution. Quantum number assignments were made for spectral lines from J = O to 57, by comparison with theoretically computed spectra which include the effects of centrifugal distortion. The following values for the band centers were determined: nu sub 1 = 1151.65 + or - 0.10/cm, nu sub 2 = 517.75 + or - 0.10/cm, and nu sub 3 = 1362.00 + or - 0.10/cm. Intensities of the observed lines have also been computed. Dipole moment derivatives were obtained
High-resolution absorption spectroscopy of the circumgalactic medium of the Milky Way
In this article we discuss the importance of high-resolution absorption
spectroscopy for our understanding of the distribution and physical nature of
the gaseous circumgalactic medium (CGM) that surrounds the Milky Way.
Observational and theoretical studies indicate a high complexity of the gas
kinematics and an extreme multi-phase nature of the CGM in low-redshift
galaxies. High-precision absorption-line measurements of the Milky Way's gas
environment thus are essential to explore fundamental parameters of
circumgalactic gas in the local Universe, such as mass, chemical composition,
and spatial distribution. We shortly review important characteristics of the
Milky Way's CGM and discuss recent results from our multi-wavelength
observations of the Magellanic Stream. Finally, we discuss the potential of
studying the warm-hot phase of the Milky Way's CGM by searching for extremely
weak [FeX] l6374.5 and [FeIVX] l5302.9 absorption in optical QSO spectra.Comment: 7 pages, 4 figures; accepted for publication in Astronomical Notes
(paper version of a talk presented at the 10th Thinkshop, Potsdam, 2013
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