Influence of an isometric fatiguing exercise on the length and passive-elastic properties of the calf muscle-tendon unit of minimally active young women

The remarkable deformability of the erythrocyte derives in large part from the elastic properties of spectrin, the major component of the membrane skeleton. It is generally accepted that spectrin's elasticity arises from marked conformational changes which include variations in its overall length (1). In this work the structure of spectrin in partially expanded membrane skeletons was studied by electron microscopy to determine the molecular basis for spectrin's elastic properties. Spectrin molecules were analysed with respect to three features: length, conformation, and quaternary structure. The results of these studies lead to a model of how spectrin mediates the elastic deformation of the erythrocyte.Membrane skeletons were isolated from erythrocyte membrane ghosts, negatively stained, and examined by transmission electron microscopy (2). Particle lengths and end-to-end distances were measured from enlarged prints using the computer program MACMEASURE. Spectrin conformation (straightness) was assessed by calculating the particles’ correlation length by iterative approximation (3). Digitised spectrin images were correlation averaged or Fourier filtered to improve their signal-to-noise ratios. Three-dimensional reconstructions were performed using a suite of programs which were based on the filtered back-projection algorithm and executed on a cluster of Microvax 3200 workstations (4).

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The buckling of thin EM specimens

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100177386 ◽

1990 ◽

Vol 48 (4) ◽

pp. 850-851

Author(s):

A.R. Thölén

Keyword(s):

Electron Microscope ◽

Elastic Properties ◽

Crystal Surface ◽

Specimen Surface ◽

Radius Of Curvature ◽

Thin Foils ◽

Thin Electron ◽

Regular Patterns

Thin electron microscope specimens often contain irregular bend contours (Figs. 1-3). Very regular bend patterns have, however, been observed around holes in some ion-milled specimens. The purpose of this investigation is twofold. Firstly, to find the geometry of bent specimens and the elastic properties of extremely thin foils and secondly, to obtain more information about the background to the observed regular patterns.The specimen surface is described by z = f(x,y,p), where p is a parameter, eg. the radius of curvature of a sphere. The beam is entering along the z—direction, which coincides with the foil normal, FN, of the undisturbed crystal surface (z = 0). We have here used FN = [001]. Furthermore some low indexed reflections are chosen around the pole FN and in our fcc crystal the following g-vectors are selected:

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Severe Paradoxical Dysphonia in Two Young Women

American Journal of Speech-Language Pathology ◽

10.1044/1058-0360.0203.52 ◽

1993 ◽

Vol 2 (3) ◽

pp. 52-55 ◽

Cited By ~ 1

Author(s):

Michael Collins ◽

Robert McDonald ◽

Robert Stanley ◽

Timothy Donovan ◽

C. Frank Bonebrake

Keyword(s):

Young Women ◽

Theoretical Basis ◽

Therapeutic Regimen ◽

Instrumental Data ◽

Relationship Of ◽

The Relationship

This report describes an unusual and persistent dysphonia in two young women who had taken a therapeutic regimen of isotretinoin for intractable acne. We report perceptual and instrumental data for their dysphonia, and pose a theoretical basis for the relationship of dysphonia to this drug. We also provide recommendations for reducing the risk of acquiring a dysphonia during the course of treatment with isotretinoin.

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What Do We Want Them To Be When They Grow Up?

Perspectives on Hearing and Hearing Disorders in Childhood ◽

10.1044/hhdc20.1.27 ◽

2010 ◽

Vol 20 (1) ◽

pp. 27-31

Author(s):

Lyn Robertson

Keyword(s):

Hearing Loss ◽

Social Development ◽

Young Women ◽

Hearing Aids ◽

Test Scores ◽

Spoken Language ◽

Language Therapy ◽

Profound Hearing Loss ◽

Children With Hearing Loss ◽

Learning To Listen

Abstract Learning to listen and speak are well-established preludes for reading, writing, and succeeding in mainstream educational settings. Intangibles beyond the ubiquitous test scores that typically serve as markers for progress in children with hearing loss are embedded in descriptions of the educational and social development of four young women. All were diagnosed with severe-to-profound or profound hearing loss as toddlers, and all were fitted with hearing aids and given listening and spoken language therapy. Compiling stories across the life span provides insights into what we can be doing in the lives of young children with hearing loss.

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