Role of electromechanical and mechanoelectric effects in protein hydration under hydrostatic pressure

Four aspects of the functioning of a fluid-filled cylindrical animal have been examined, viz.: (I) the role of the body fluid as a skeleton for the interaction of the longitudinal and circular muscles of which the animal must be composed; (2) the measurement of the maximum thrust which the animal can exert by measurement of its internal hydrostatic pressure; (3) the application of the force to the substratum and the part played by friction; (4) the relation between the changes in dimensions of the animal and the working length of the muscles. Under (1) the necessity for a longitudinal and circular construction has been shown and the necessity for a closed system emphasized. Under (2) the pressure exerted on the body fluid by the contraction of the longitudinal and circular muscles is discussed, and from their cross-sectional areas it is shown to be probable that when contracting maximally in Lumbricus they are not balanced, but that the longitudinals are about ten times as strong as the circulars. Under (3) it is shown that the strength of an animal as measured by its internal hydrostatic pressure is sufficient to account for its customary activities. Use which may be made of the longitudinals during burrowing is pointed out. Under (4) it is shown to be mechanically sound for burrowing animals of cylindrical form to be ‘fat’, but that a ‘thin’ animal is more efficient at progression.

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Role of hydrostatic pressure and wall effect in solidification of TC8 alloy

npj Microgravity ◽

10.1038/s41526-019-0083-2 ◽

2019 ◽

Vol 5 (1) ◽

Cited By ~ 1

Author(s):

Xinghong Luo ◽

Yaya Wang ◽

Yang Li

Keyword(s):

Hydrostatic Pressure ◽

Normal Gravity ◽

Early Stage ◽

Solidification Process ◽

Wall Effect ◽

Solidification Microstructure ◽

Drop Tube ◽

Aspect Ratios ◽

Equiaxed Grains

Abstract The solidification experiments of TC8 alloy under both microgravity and normal gravity were conducted using a drop tube. The solidification microstructure were found composed of fine equiaxed grains formed at early stage and bigger elongated grains formed at later stage. Between the two kinds of grains a curved transition interface was observed in 1g sample, while that in μg sample was almost flat. Generally, the amounts and aspect ratios of the grains are larger, and the grain sizes are smaller in 1g sample. Besides, no visible element macrosegregation occurred in both samples. The results suggest that the solidification velocities of the samples were rapid, and consequently the convection effect and solute transport effect caused by gravity had little influence on the solidification microstructure. Therefore, the solidification process was mainly controlled by thermal diffusion, and hydrostatic pressure and wall effect played a great role in it.

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Role of package headspace on multilayer films subjected to high hydrostatic pressure

Packaging Technology and Science ◽

10.1002/pts.2432 ◽

2019 ◽

Vol 32 (5) ◽

pp. 247-257 ◽

Cited By ~ 4

Author(s):

Saleh Al‐Ghamdi ◽

Barbara Rasco ◽

Juming Tang ◽

Gustavo V. Barbosa‐Cánovas ◽

Shyam S. Sablani

Keyword(s):

Hydrostatic Pressure ◽

High Hydrostatic Pressure ◽

Multilayer Films

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Role of luminal hydrostatic pressure in proximal tubular fluid reabsorption in the rat

American Journal of Physiology-Legacy Content ◽

10.1152/ajplegacy.1975.229.3.813 ◽

1975 ◽

Vol 229 (3) ◽

pp. 813-819 ◽

Cited By ~ 2

Author(s):

A Grandchamp ◽

Scherrer ◽

D Scholer ◽

J Bornand

Keyword(s):

Hydrostatic Pressure ◽

Proximal Tubule ◽

Pressure Difference ◽

Unit Area ◽

Rat Kidney ◽

Fluid Reabsorption ◽

Proximal Tubular ◽

Tubular Fluid Reabsorption ◽

Selective Change

The effect of small changes in intraluminal hydrostatic pressure (P) on the tubular radius (r) and the net fluid reabsorption per unit of surface area of the tubular wall (Js) has been studied in the proximal tubule of the rat kidney. The split-drop method was used to simultaneously determine Js and r. Two standardized split-drop techniques A and B allow selective change in P. P was 31.6 +/- 1.3 mmHg in technique A and 15.5 +/- 1.5 in technique B. The pressure difference significantly affected the tubular radius; r was 21.9 +/- 0.4 and 18.6 +/- 0.5 mum in the split drop A and B, respectively. In contrast, net transepithelial fluid reabsorption Js was unchanged. Js amounted to 2.72 +/- 0.20, and 2.78 +/- 0.33 10(-5) cm3 cm-2 s-1 in split drop A and B. The absence of variations in Js could result from two opposite effects of pressure. P might enhance Js by increased ultrafiltration. However, the rise in r might decrease the density of the intraepithelial transport paths per unit area of tubular wall and therefore might decrease Js.

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