Roasting Process of Coffee Beans as Studied by Nuclear Magnetic Resonance: Time Course of Changes in Composition

2012 ◽  
Vol 60 (4) ◽  
pp. 1005-1012 ◽  
Author(s):  
Feifei Wei ◽  
Kazuo Furihata ◽  
Masanori Koda ◽  
Fangyu Hu ◽  
Takuya Miyakawa ◽  
...  
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Time Course ◽  
Coffee Beans ◽  
Roasting Process ◽  
Nuclear Magnetic

Time Course of Cerebral Magnetic Resonance Changes after Electroconvulsive Therapy

1990 ◽  
Vol 156 (4) ◽  
pp. 551-553 ◽  
Author(s):  
A. I. F. Scott ◽  
R. H. B. Douglas ◽  
A. Whitfield ◽  
R. E. Kendell
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Electroconvulsive Therapy ◽  
Cerebral Hemisphere ◽  
Time Course ◽  
Magnetic Resonance Images ◽  
Depressed Patients ◽  
Baseline Values ◽  
Nuclear Magnetic

Nuclear magnetic resonance images of the non-dominant cerebral hemisphere were obtained in 20 unipolar depressed patients immediately before and 25 minutes after electroconvulsive therapy (ECT). T1 values rose about 1 %. Repeated scanning up to 24 hours after ECT was carried out in 13 of these patients. The greatest change in magnetic resonance images was two hours after ECT, and thereafter images gradually returned to baseline values. There was no correlation between magnetic resonance changes and the time taken to become re-orientated after ECT.

scholarly journals Acute Cerebral Ischaemia: Concurrent Changes in Cerebral Blood Flow, Energy Metabolites, pH, and Lactate Measured with Hydrogen Clearance and 31P and 1H Nuclear Magnetic Resonance Spectroscopy. I. Methodology

1987 ◽  
Vol 7 (2) ◽  
pp. 199-206 ◽  
Author(s):  
David G. Gadian ◽  
Richard S. J. Frackowiak ◽  
H. Alan Crockard ◽  
Edward Proctor ◽  
Kathryn Allen ◽  
...  
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Time Course ◽  
Metabolic Effects ◽  
Laboratory Animals ◽  
Resonance Spectroscopy ◽  
Energy Metabolites ◽  
Flow Energy ◽  
Hydrogen Clearance ◽  
Nuclear Magnetic

CBF has been measured with the hydrogen clearance technique in the two cerebral hemispheres of the gerbil under halothane anaesthesia. This has been correlated with changes in local pH, tissue lactate, and phosphorus energy metabolites measured in the same animals with 1H and 31P nuclear magnetic resonance (NMR) spectroscopy. The NMR measurements were made with two surface coils, one on each hemisphere. This article describes the experimental details and shows that in acute unilateral or bilateral forebrain ischaemia metabolic changes can be monitored by NMR with no significant interhemispheric cross talk. The metabolic effects of reperfusion are also shown. The model allows the definition of the time course of the metabolic consequences of regional ischaemia and reperfusion in individual laboratory animals.

Hepatic phosphate trapping, decreased ATP, and increased feeding after 2,5-anhydro-D-mannitol

1994 ◽  
Vol 266 (1) ◽  
pp. R112-R117 ◽  
Author(s):  
N. E. Rawson ◽  
H. Blum ◽  
M. D. Osbakken ◽  
M. I. Friedman
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Time Course ◽  
Time Frame ◽  
High Energy ◽  
Resonance Spectroscopy ◽  
Phosphate Diesters ◽  
Layer Chromatography ◽  
Nuclear Magnetic

The mechanism by which the fructose analogue 2,5-anhydro-D-mannitol (2,5-AM) elicits feeding behavior was investigated by studying its metabolism and biochemical effects in liver. Thin-layer chromatography of liver extracts from rats given 2,5-AM containing 14C-labeled 2,5-AM showed that the analogue is phosphorylated in vivo with a time course that parallels the eating response. In vivo 31P nuclear magnetic resonance spectroscopy of rat liver during intravenous infusion of 2,5-AM and high-resolution nuclear magnetic resonance analyses of liver extracts showed that 2,5-AM is rapidly phosphorylated in liver, trapping hepatic phosphate and decreasing ATP, inorganic phosphate, and phosphate diesters. These changes occurred in a time frame in which the feeding response is elicited in conscious animals given the same dose of 2,5-AM by the same route. During an interval in which 2,5-AM increased eating, it also increased urinary uric acid excretion, implicating enhanced adenosine degradation in the reduction in hepatic ATP. These results provide the first direct evidence that changes in a high-energy phosphate-carrying compound in liver may provide a signal to initiate eating behavior.

Rapid Authentication of Coffee Blends and Quantification of 16-O-Methylcafestol in Roasted Coffee Beans by Nuclear Magnetic Resonance

2014 ◽  
Vol 62 (51) ◽  
pp. 12309-12314 ◽  
Author(s):  
Elisabetta Schievano ◽  
Claudia Finotello ◽  
Elisabetta De Angelis ◽  
Stefano Mammi ◽  
Luciano Navarini
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Roasted Coffee ◽  
Coffee Beans ◽  
Roasted Coffee Beans ◽  
Nuclear Magnetic

An emerging technology: Nuclear magnetic resonance microscopy

1988 ◽  
Vol 46 ◽  
pp. 1000-1001
Author(s):  
M.J. Hennessy ◽  
E. Kwok
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Relaxation Times ◽  
Basic Research ◽  
Local Environment ◽  
Magnetic Resonance Images ◽  
Nmr Microscopy ◽  
Mri Scans ◽  
Temperature Relaxation ◽  
Nuclear Magnetic

Much progress in nuclear magnetic resonance microscope has been made in the last few years as a result of improved instrumentation and techniques being made available through basic research in magnetic resonance imaging (MRI) technologies for medicine. Nuclear magnetic resonance (NMR) was first observed in the hydrogen nucleus in water by Bloch, Purcell and Pound over 40 years ago. Today, in medicine, virtually all commercial MRI scans are made of water bound in tissue. This is also true for NMR microscopy, which has focussed mainly on biological applications. The reason water is the favored molecule for NMR is because water is,the most abundant molecule in biology. It is also the most NMR sensitive having the largest nuclear magnetic moment and having reasonable room temperature relaxation times (from 10 ms to 3 sec). The contrast seen in magnetic resonance images is due mostly to distribution of water relaxation times in sample which are extremely sensitive to the local environment.

Nuclear magnetic resonance microscopy

1989 ◽  
Vol 47 ◽  
pp. 828-829
Author(s):  
Paul C. Lauterbur
Keyword(s):  
Magnetic Field ◽  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Magnetic Fields ◽  
Signal To Noise ◽  
Field Gradients ◽  
Useful Signal ◽  
Magnetic Field Gradients ◽  
Observation Times ◽  
Nuclear Magnetic

Nuclear magnetic resonance imaging can reach microscopic resolution, as was noted many years ago, but the first serious attempt to explore the limits of the possibilities was made by Hedges. Resolution is ultimately limited under most circumstances by the signal-to-noise ratio, which is greater for small radio receiver coils, high magnetic fields and long observation times. The strongest signals in biological applications are obtained from water protons; for the usual magnetic fields used in NMR experiments (2-14 tesla), receiver coils of one to several millimeters in diameter, and observation times of a number of minutes, the volume resolution will be limited to a few hundred or thousand cubic micrometers. The proportions of voxels may be freely chosen within wide limits by varying the details of the imaging procedure. For isotropic resolution, therefore, objects of the order of (10μm) may be distinguished.Because the spatial coordinates are encoded by magnetic field gradients, the NMR resonance frequency differences, which determine the potential spatial resolution, may be made very large. As noted above, however, the corresponding volumes may become too small to give useful signal-to-noise ratios. In the presence of magnetic field gradients there will also be a loss of signal strength and resolution because molecular diffusion causes the coherence of the NMR signal to decay more rapidly than it otherwise would. This phenomenon is especially important in microscopic imaging.

Sign in / Sign up

Export Citation Format

Share Document