The linear operating range of high-quality measurement accelerometers and microphones has for many years been significantly better than that of the analog signal conditioning electronics and analog-to-digital converters (ADCs) of the data acquisition systems. This is despite the fact that data acquisition systems today are typically based on 24-bit ADCs, and theoretically able to handle signal ...

C. Schuster, W. Dreher, D. Leibfritz FB 2 (Chemistry), University of Bremen, Bremen, Germany, Center of Advanced Imaging (CAI), Bremen, Germany Introduction Over the past years several methods for fast 3D H MR spectroscopic imaging (MRSI) derived from corresponding fast MRI methods have been proposed to map the distribution of human brain metabolites. Besides echo planar MRSI and spiral MRSI [1...

In a recent extended x-ray absorption fine structure (EXAFS) analysis of icosahedral and a-phases of AlMnSi it was shown frgm the Mn-Mn scattering that an icosahedron cage of Mn atoms with edge length 2 5 A is the structural unit in the icosahedral phase. In this paper we present results on the radial distribution function (RDF) of the first shell A1 atoms yielded by a direct Fourier transform ...

Metabolic studies have arguably been conducted since the 13th centurywith Ibn al-Nafis stating that “the body and its parts are in a continuous state of dissolution and nourishment, so they are inevitably undergoing permanent change” (Mahdi, 1974). However, it was studies in yeast in the last decades of the 19th century and the first decades of the 20th century (Kühne, 1877; Buchner, 1897; Sumn...

Introduction Oxygen-17 (O) MRI is a promising tool for assessing in vivo metabolic tissue information at ultra high fields [1]. It has been shown that oxygen consumption can be determined by detection of the signal increase due to inhalation of enriched O gas. However, O-MRI suffers from low inherent SNR because of the low natural abundance (0.037%) and short relaxation times of the O nucleus (...

Introduction H MRS of the prostate is one of the most reliable, minimally invasive approach for distinguishing prostate cancer from benign diseases and healthy tissues [1]. Spectral intensity ratio of choline to citrate (Cho/Cit) and mainly ratio of Cho, polyamines (PA), and creatine (Cr) to Cit (Cho+PA+Cr)/Cit are used as specific markers for the cancer. However, in interpretation of these mar...

Target audience. Researchers interested in EPI, center-out readout strategies, and dynamic vascular and perfusion imaging. Purpose. 2D EPI and EPSI modifications relying on center-out trajectories have been introduced recently. Here, a 3D variant with cylindrical encoding is combined with an arterial spin labeling (ASL) technique that created a well-defined bolus at the positions of large brain...

Introduction: Diffusion spectral imaging (DSI) has the potential to resolve crossing fibers. However, acquisition of the DSI data involves long scan times, making it impractical for routine scanning. A simple way to reduce the scan time is to limit the number of q-space points sampled and fill the q-space by exploiting its symmetry. However, the smallest number of q-space points needed to gener...

This Letter proposes a controlled coupling process for information processing. The net effect of conventional coupling is isolated from the dynamical system and is analyzed in depth. The stability of the process is studied. We show that the proposed process can locally minimize the smoothness and the fidelity of dynamical data. A digital filter expression of the controlled coupling process is d...

Introduction: Recently Frydman et al proposed a novel mechanism for directly forming images in k space using frequency sweep encoding (1, 2). It relies on the quadratic dependence of magnetization phase on position. In combination with EPI-type readout, this method has found applications in single-shot spin-echo imaging of human and rat brains (3, 4). Its sequential excitation of magnetization ...