Gravitational fluctuations along the line-of-sight from the surface of last scatter to the observer distort the microwave background in several related ways: The fluctuations deflect the photon path (gravitational lensing), the decay of the gravitational potential produces additional fluctuations (ISW effect) and scattering off of hot gas in clusters produce additional fluctuations (Sunyaev-Zel...

Introduction: Low frequency fluctuations (LFFs) in T2*-weighted MR images have been used to map functional connectivity in both humans and rats [1, 2, 3]. Most FC studies utilize gradient echo EPI (GE-EPI) because of its high sensitivity to BOLD signal fluctuations. However, fMRI studies have shown that the BOLD signal in GE-EPI images contains a strong contribution from large veins. At high fi...

The line shapes detected in coherent femtosecond vibrational spectroscopies contain direct signatures of peptide conformational fluctuations through their effect on vibrational frequencies and intermode couplings. These effects are simulated in trialanine using a Green's function solution of a stochastic Liouville equation constructed for four collective bath coordinates (two Ramachandran angle...

Heart rate fluctuations occur in the low-frequency range (<0.1 Hz) probed in functional magnetic resonance imaging (fMRI) studies of resting-state functional connectivity and most fMRI block paradigms and may be related to low-frequency blood-oxygenation-level-dependent (BOLD) signal fluctuations. To investigate this hypothesis, temporal correlations between cardiac rate and resting-state fMRI ...

Sensor jitter introduces non-white noise fluctuations in imagery of cluttered scenes. These fluctuations are a major source of interference in the detection of weak time-dependent signals, which may be associated with a subject’s appearance, motion, or brightness modulation. Due to the presence of sensor pattern noise and uncertainty in the scene’s subpixel spatial structure, standard frame-to-...

Detecting the 21-cm hyperfine transition from neutral hydrogen in intergalactic medium is our best probe for understanding astrophysical processes driving Epoch of Reionisation (EoR). The primary means a detection this signal through statistical measurement spatial fluctuations using power spectrum (PS). However, non-Gaussian meaning PS, which only measures Gaussian fluctuations, sub-optimal ch...

Abstract We investigate tomography of 21-cm brightness temperature fluctuations during the Dark Ages as a probe for constraining primordial non-Gaussianity. expand up to cubic order in perturbation theory and improve previous models signal by including effect free electron fraction. Using modified standard methods that include baryonic pressure effects we derive an improved secondary bispectrum...

In this first attempt to extract a map of the kinetic Sunyaev-Zel’dovich (KSZ) temperature fluctuations from the cosmic microwave background (CMB) anisotropies, we use a method which is based on simple and minimal assumptions. We first focus on the intrinsic limitations of the method due to the cosmological signal itself. We demonstrate using simulated maps that the KSZ reconstructed maps are i...

As the quality of cosmological data continue to improve, it is natural to test the statistics of primordial fluctuations: are they Gaussian or non-Gaussian? I review a model which generates non-Gaussian adiabatic fluctuations from inflation. Current investigations suggest that there may possibly be a non-Gaussian signal in large angle cosmic microwave background anisotropy data. Statistics of m...

In their report on laser Doppler flow measurements (J. Biomed. Eng. 1985, 7, 225) Boggett et al. compared, among other things, three different light sources for use in a laser Doppler device. The aim of that study was to distinguish between Doppler shifted and non-shifted backscattered light to obtain a flow dependent signal, which is not caused by intensity fluctuations due to number fluctuati...