Scalar Relaxation of the Second Kind: A Potential Source of Information on the Dynamics of Molecular Movements. 1. Investigation of Solution Reorientation of N-Methylpyridone and 1,3-Dimethyluracil Using Measurements of Longitudinal Relaxation Rates in the Rotating Frame

2012 ◽  
Vol 116 (39) ◽  
pp. 9632-9638 ◽  
Author(s):  
Adam Gryff-Keller ◽  
Dominika Kubica
Keyword(s):  
Rotating Frame ◽  
Relaxation Rates ◽  
Potential Source ◽  
Longitudinal Relaxation ◽  
Scalar Relaxation ◽  
Source Of Information

Scalar Relaxation of the Second Kind. A Potential Source of Information on the Dynamics of Molecular Movements. 4. Molecules with Collinear C–H and C–Br Bonds

2014 ◽  
Vol 118 (23) ◽  
pp. 4063-4070 ◽  
Author(s):  
Piotr Bernatowicz ◽  
Dominika Kubica ◽  
Michał Ociepa ◽  
Artur Wodyński ◽  
Adam Gryff-Keller
Keyword(s):  
Potential Source ◽  
Scalar Relaxation ◽  
Source Of Information

Evidence of chemically mediated population recognition in coho salmon (Oncorhynchus kisutch)

1986 ◽  
Vol 64 (1) ◽  
pp. 84-87 ◽  
Author(s):  
Thomas P. Quinn ◽  
Graeme M. Tolson
Keyword(s):  
British Columbia ◽  
Coho Salmon ◽  
Oncorhynchus Kisutch ◽  
The Other ◽  
Potential Source ◽  
Source Of Information

To test the hypothesis that population-specific pheromones guide adult salmonids to their natal streams, juvenile and adult coho salmon (Oncorhynchus kisutch) were tested for chemosensory responses in two-choice tanks. Coho salmon from Quinsam and Big Qualicum rivers, British Columbia, Canada, distinguished their own population from the other. Tagging evidence indicates that straying between these two rivers and a third, geographically intermediate river seldom occurs. Thus, population-specific chemicals constitute a potential source of information for homing coho salmon, though their role vis-à-vis imprinted odors from other sources could not be evaluated.

scholarly journals “Enwau Prydeinig gwyn?” Problematizing the idea of “White British” names and naming practices from a Welsh perspective

2018 ◽  
Vol 14 (3) ◽  
pp. 251-259
Author(s):  
Sara Louise Wheeler
Keyword(s):  
National Identity ◽  
Indigenous Communities ◽  
Underlying Assumption ◽  
Cultural Community ◽  
Personal Names ◽  
Potential Source ◽  
Source Of Information ◽  
Opening Up ◽  
Naming Practices

Our personal names are a potential source of information to those around us regarding several interconnected aspects of our lives, including our: ethnic, geographic, linguistic and cultural community of origin, and perhaps our national identity. However, interpretations regarding identifiably “White British” names and naming practices are problematic, due to the incorrect underlying assumption of a homogeneity in the indigenous communities of ‘Britain.’ The field of names and naming is a particularly good example of the wide linguistic and cultural chasm between the Welsh and English indigenous ‘British’ communities, and thus the generally paradoxical concept of “Britishness” in its wider sense. In this paper, I will explore names and naming practices which are particularly distinctive to a Welsh context, thus unearthing and opening up for wider debate the hidden diversity within the assumed and imposed category of “White British privilege.”

Applications of high-resolution 13C and 15N n.m.r. of solids

1981 ◽  
Vol 299 (1452) ◽  
pp. 593-608 ◽  
Keyword(s):  
High Resolution ◽  
Spin Diffusion ◽  
Magic Angle Spinning ◽  
Spin Lattice Relaxation ◽  
Spatial Proximity ◽  
Magic Angle ◽  
Rotating Frame ◽  
Cross Polarization ◽  
Relaxation Rates ◽  
Relaxation Parameters

The combination of cross polarization, dipolar decoupling and magic angle spinning results in liquid-like high-resolution 13 C and 15 N n.m.r. spectra of a wide variety of solid materials. Structural determinations based on such 13 C n.m.r. spectra include the measurement of the extent to which pyrolysed polyacrylonitrile fibres (Orion) retain aliphatic character during the first step of the production of a carbon fibre, the determination of the chemical identity of the cross links formed from an acetyleneterminated polyimide resin, and the characterization of the metabolic products of a bacterial fermentation of wood lignin. All of these non-destructive analyses are performed on intact heterogeneous samples. The high resolution of the carbon experiment can also be exploited by obtaining proton spin-lattice relaxation parameters for chemically different protons in solids. Because of spin diffusion, these parameters are dependent on spatial proximity and so are helpful in measuring the homogeneity of solid blends of polymers such as poly(phenylene oxide) and polystyrene. High-resolution 13 C n.m.r. spectra of polymers can also be used for measuring microscopic chain dynamics. 13 C rotating-frame relaxation parameters observed for polycarbonate and poly (ethylene terephthalate) are related to the effects on motion of annealing, additives and structural substitutions. Individual relaxation rates are observed for individual carbons, so the behaviour of side groups is cleanly separated from that of the main chain. All of the line-narrowing and sensitivity-enhancing techniques applied to 13 C n.m.r. of solids work equally well for 15 N n.m.r. Use of 15 N rotating-frame and cross-polarization parameters leads to the assessment of the relative concentrations of 13 C - 15 N and 12 C - 15 N pair concentrations in the main chains of multiply labelled proteins. Such measurements can be used to characterize the rate of protein turnover in fully expanded soybean leaves, as well as the details of protein synthesis in cultured soybean cotyledons.

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