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Transcutaneous measurement of volume blood flow
Blood flow velocity measurements, using Doppler velocimeter, are described. The ability to measure blood velocity using ultrasound is derived from the Doppler effect; the change in frequency which occurs when sound is reflected or transmitted from a moving target. When ultrasound of the appropriate frequency is transmitted through a moving blood stream, the blood cells act as point scatterers of ultrasonic energy. If this scattered ultrasonic energy is detected, it is found to be shifted in frequency according to the velocity of the blood cells, nu, the frequency of the incident sound, f sub o, the speed of sound in the medium, c, and the angle between the sound beam and the velocity vector, o. The relation describing this effect is known as the Doppler equation. Delta f = 2 f sub o x nu x cos alpha/c. The theoretical and experimental methods are evaluated
Mafic intrusions on Campobello Island: implications for New Brunswick - Maine correlations
Late Ordovician through Early Devonian units of the Passamaquoddy Bay area are interpreted to represent sequences that evolved in arc and back-arc environments. The main elements of the arc are exposed on Campobello Island and include a predominantly felsic volcanic sequence to the northeast, a sequence of intercalated turbidite and mafic volcanic rocks to the southwest, and matic dyke swarms throughout. Petrographic. geochemical, and 40Ar/39Ar studies of these rocks record episodic deformation and varying degrees of metamorphism up to lower amphibolite facies, and a protracted history of mafic magma injection from a similar source beginning in the Early Silurian. These features, combined with stratigraphic relationships and overall structural patterns, indicate a rapid transition from felsic- to mafic-dominated magmatism accompanied by radical changes in the depositional regime in the arc with time, and exposure of progressively deeper crustal levels towards the northeast within the arc.
Review of the assignment of other units in the Passamaquoddy Bay region to major tectonostratigraphic bells north of Campobello Island clarifies regional correlations and provides possible additional links to Neoproterozoic basement in the area.
RÉSUMÉ
Les unités de l'Ordovicien superieur au Dévonicn inférieur du secteur de la baie Passamaquoddy sont interprétées comme des unités représentatives de séquences ayant évolué dans des environnements d'arc et d'arriére-arc. Les principaux éléments de de l'arc affleurent sur l'ile Campobello et component une séquence principalcment volcanofelsique au nord-est. une sequence volcanomafique/turbiditique intercalée au sud-ouest et des groupes de filons mafiques un peu panout. Des études pétrographiques. géochimiques et 40Ar/39Ar de ces roches rélèvent une déformation épisodique et des degrés divers de métamorphisme jusqu'au faciès amphibolique infèrieur, ainsi que des antécédents prolongés d'injection de magma mafique d'une source similairc à partir du Silurien inferieur. Ces particulierités conjuguécs aux relations stratigraphiques et aux configurations slructurales générates, révèlent une transition rapide d'un magmatisme à prédominance mafique a un magmatisme à prédominance mafique accompagné de changements spectaculaires dans te régime de sédimentation à l'intérieur de l'are avec le temps, ainsi qu'un affleurement de niveaux crustaux progressivement plus profonds vers le nord-est a l'intcrieur de l'are.
L'examen de l'affectation des autres unités dans la region de la baie Passamaquoddy aux principals structures teconostratigraphiques au nord de l'ile Campobello clarifie les correlations régionalcs et foumit des liens supplémentaires possibles avec le socle du Protéroique supérieur du secteur.
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Development of ultrasonic methods for hemodynamic measurements
A transcutanous method to measure instantaneous mean blood flow in peripheral arteries of the human body was defined. Transcutanous and implanted cuff ultrasound velocity measurements were evaluated, and the accuracies of velocity, flow, and diameter measurements were assessed for steady flow. Performance criteria were established for the pulsed Doppler velocity meter (PUDVM), and performance tests were conducted. Several improvements are suggested
Obscuration in the Host Galaxies of Soft X-ray Selected Seyferts
We define a new sample of 96 low-redshift (z<0.1), soft X-ray selected
Seyferts from the catalog of the Einstein Slew Survey (Elvis etal. 1992,
Plummer et al. 1994). We probe the geometry and column depth of obscuring
material in the host-galaxy disks using galaxian axial ratios determined mainly
from the Digitized Sky Survey. The distribution of host-galaxy axial ratios
clearly shows a bias against edge-on spirals, confirming the existence of a
geometrically thick layer of obscuring material in the host-galaxy planes. Soft
X-ray selection recovers some of the edge-on objects missed in UV and visible
surveys but still results in 30% incompleteness for Type 1's. We speculate that
thick rings of obscuring material like the ones we infer for these Seyferts
might be commonly present in early type spirals, sitting at the Inner Lindblad
Resonances of the nonaxisymmetric potentials of the host galaxies.Comment: 14 pages including 2 tables and 3 eps figures, aas2pp4.sty, to appear
in Ap
NMA Survey of CO and HCN Emission from Nearby Active Galaxies
High resolution (a few arcseconds) observations of CO(1-0) and HCN(1-0)
emission from nearby Seyfert galaxies have been conducted with the Nobeyama
Millimeter Array. Based on the observed CO distributions and kinematics,we
suggest that a small scale (a few 100 pc - a few kpc) distortion of the
underlying potential seems to be necessary for Seyfert activity, although it is
not a sufficient condition. We also find that the Toomre's Q values in the
centers of Seyfert galaxies tend to be larger than unity, indicating the
circumnuclear molecular gas disks around Seyfert nuclei would be
gravitationally stable. The HCN/CO integrated intensity ratios (R_HCN/CO) range
over an order of magnitude, from 0.086 to 0.6. The Seyfert galaxies with high
R_HCN/CO may have an extended (r ~ 100 pc scale) envelope of obscuring
material. The presence of kpc scale jet/ outflow might be also related to the
extremely high R_HCN/CO.Comment: To appear in the Proceedings of the 3rd Cologne-Zermatt Symposium,
``The Physics and Chemistry of the Interstellar Medium'
Uniqueness and Nondegeneracy of Ground States for in
We prove uniqueness of ground state solutions for the
nonlinear equation in , where
and for and for . Here denotes the fractional Laplacian
in one dimension. In particular, we generalize (by completely different
techniques) the specific uniqueness result obtained by Amick and Toland for
and in [Acta Math., \textbf{167} (1991), 107--126]. As a
technical key result in this paper, we show that the associated linearized
operator is nondegenerate;
i.\,e., its kernel satisfies .
This result about proves a spectral assumption, which plays a central
role for the stability of solitary waves and blowup analysis for nonlinear
dispersive PDEs with fractional Laplacians, such as the generalized
Benjamin-Ono (BO) and Benjamin-Bona-Mahony (BBM) water wave equations.Comment: 45 page
Stories of success: Cultural narratives and personal stories of elite and professional athletes
Using a narrative methodology to explore the stories Olympic and elite athletes tell about success, we identified three alternatives to the dominant conception of success as the achievement of performance outcomes. In these alternatives, success is storied as: (1) âI did the best that I couldâ â a controllable and sustainable story of effort and application; (2) âItâs the closest thing you can get to flyingâ â a story where success relates to embodied experience and discovery; (3) âPeople I made the journey withâ â which prioritises relationships and connection between people. We reflect on three key insights: (1) success is a multidimensional concept, broader than the singular conception encapsulated within the dominant performance narrative; (2) through various narrative strategies, experienced athletes resist cultural pressures towards a singular conception of success; (3) for long-term performance and well-being, it is necessary to work towards multiple forms of success over time and across contexts
Generational research: between historical and sociological imaginations
This paper reflects on Julia Brannenâs contribution to the development of theory and methods for intergenerational research. The discussion is contextualised within a contemporary âturn to timeâ within sociology, involving tensions and synergies between sociological and historical imagination. These questions are informed by a juxtaposition of Brannenâs four-generation study of family change and social historian Angela Davisâs exploration women and the family in England between 1945 and 2000. These two studies give rise to complementary findings, yet have distinctive orientations towards the status and treatment of sources, the role of geography in research design and limits of generalisatio
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