This report proposes a standard method to characterize variability and sensitivity of functional neuroimaging experiments. Most functional neuroimaging analyses result in statistic images of signal-to-noise. However, it is essential to examine both signal and noise individually, to characterize sensitivity and to identify artifacts. Confidence intervals simultaneous convey signal and noise but ...

BACKGROUND AND PURPOSE MR imaging-detected carotid plaque hemorrhage is associated with an increased risk of recurrent ischemic cerebrovascular events and could be an indicator of disease progression; however, there are limited data regarding the dynamics of the MR imaging-detected carotid plaque hemorrhage signal. We assessed the temporal change of this signal and its impact on carotid disease...

Hyperoxia during T2*-weighted magnetic resonance imaging (oxygen challenge imaging (OCI)) causes T2*-weighted signal change that is dependent on cerebral blood volume (CBV) and oxygen extraction fraction (OEF). Crossed cerebellar diaschisis (CCD), where CBV is reduced but OEF is maintained, may be used to understand the relative contributions of OEF and CBV to OCI results. In subjects with larg...

the analytic signal method is a semiautomatic method for estimating the location of causative bodies in magnetic and gravity methods. the application of analytic signal for interpretation of two dimensional (2d) structures was introduced by nabighian (1972). the analytic signal is defined as a complex function in which the real and imaginary parts are a pair of hilbert transforms. in other word...

This work presents a novel approach to detect a change in the state of a signal. We propose that in a given state, the values of a signal vary in a subrange of a Gaussian distribution. We describe methods to monitor a signal in real time for change points based upon sub-Gaussian fitting. The proposed algorithm was implemented and tested on heartrate variability data.

Stable carbon isotope composition (δ13C) recorded in trees responds sensitively to the changing environmental conditions and thus provides a powerful tool for paleoenvironmental reconstructions. The retrospective interpretation of tree δ13C signal depends on comprehensive understanding how physiological signals are during photosynthesis is modified after photosynthesis. This thesis aims improve...