Determination of the Lowest Coefficient for a One-Dimensional Parabolic Equation in a Domain with Free Boundary

2014 ◽  
Vol 65 (11) ◽  
pp. 1698-1719 ◽  
Author(s):  
H. A. Snitko
Keyword(s):  
Parabolic Equation ◽  
Free Boundary ◽  
One Dimensional

Improved thin-layer chromatographic determination of phospholipids in gastric aspirate from newborns, for assessment of lung maturity.

1988 ◽  
Vol 34 (4) ◽  
pp. 736-738 ◽  
Author(s):  
D Serrano de la Cruz ◽  
E Santillana ◽  
A Mingo ◽  
G Fuenmayor ◽  
A Pantoja ◽  
...  
Keyword(s):  
Thin Layer ◽  
Fetal Lung ◽  
Chromatographic Determination ◽  
Solvent Mixture ◽  
Gastric Aspirate ◽  
One Dimensional ◽  
Acetic Acid Water ◽  
Chromatographic Resolution ◽  
Lung Maturity

Abstract This one-dimensional thin-layer chromatographic method is used for assay of phospholipids in the gastric aspirate of newborns. The solvent mixture (chloroform/hexane/methanol/glacial acetic acid/water, 12/7/4/3/0.3 by vol) completely resolves lecithin, sphingomyelin, phosphatidylinositol, phosphatidylserine, phosphatidylethanolamine, and phosphatidylglycerol. The method is simple, precise, inexpensive, and rapid (chromatographic development takes less than 25 min) and gives high chromatographic resolution. We used this method to determine the lecithin/sphingomyelin densitometric ratio (L/S ratio) and the phosphatidylglycerol percentage in 200 samples of gastric aspirate and found an L/S ratio of 2.5 to be a satisfactory cutoff value for distinguishing fetal lung maturity and immaturity. We confirmed that the presence of phosphatidylglycerol excluded the possibility of respiratory distress.

Formalism for the determination of intermediate stress gradients using X-ray diffraction

2009 ◽  
Vol 42 (2) ◽  
pp. 192-197 ◽  
Author(s):  
Thomas Gnäupel-Herold
Keyword(s):  
Lattice Strain ◽  
Narrow Line ◽  
X Ray Diffraction ◽  
Beam Spot ◽  
Strain Measurements ◽  
One Dimensional ◽  
X Ray ◽  
Stress Gradients ◽  
Shaped Beam

A method is outlined that allows the determination of one-dimensional stress gradients at length scales greater than 0.2 mm. By using standard four-circle X-ray diffractometer equipment and simple aperture components, length resolutions down to 0.05 mm in one direction can be achieved through constant orientation of a narrow, line-shaped beam spot. Angle calculations are given for the adjustment of goniometer angles, and for the effective azimuth and tilt of the scattering vector for general angle settings in a four-circle goniometer. The latter is necessary for the computation of stresses from lattice strain measurements.

On the determination of the right-hand side in a parabolic equation

2012 ◽  
Vol 62 (11) ◽  
pp. 1672-1683 ◽  
Author(s):  
A. Ashyralyev ◽  
A.S. Erdogan ◽  
O. Demirdag
Keyword(s):  
Parabolic Equation ◽  
Right Hand ◽  
The Right

Experimental determination of spectral densities in quasi-one-dimensional electron systems

1998 ◽  
Vol 249-251 ◽  
pp. 175-179
Author(s):  
B. Kardynal ◽  
C.H.W. Barnes ◽  
E.H. Linfield ◽  
D.A. Ritchie ◽  
J.T. Nicholls ◽  
...  
Keyword(s):  
Experimental Determination ◽  
Electron Systems ◽  
Dimensional Electron ◽  
Spectral Densities ◽  
One Dimensional
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