Weight and Shape

Signer and Mosimann (1941) fractionated gelatin by alcohol precipitation in the presence of urea into samples of different molecular weights, and Mosimann (1944) studied two fractions with the ultracentrifuge, in the presence of urea. From measurements of sedimentation equilibrium on the most highly soluble fraction, he obtained values of 16,400 for ( = Swjilf / LuiM ) and 18,000 for ( = ZwiM , / Zn M ). The rather 

It may be concluded that individual gelatin molecules range in size up to a molecular weight of at least 100,000 and that the larger molecules are neither fully extended polypeptide chains, nor compact, approximately spherical molecules, nor randomly coiled chains whose shape would on the average be spherical if the parent molecule is a compact ellipsoid of revolution, its axial ratio is about 47 if it is a coiled chain, the coiling is not random, but such that the coil is considerably extended in one direction. 

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The simplicity gained by choosing identical weight and shape functions has made the standard Galerkin method the most widely used technique in the finite element solution of differential equations. Because of the centrality of this technique in the development of practical schemes for polymer flow problems, the entire procedure of the Galerkin finite element solution of a field problem is further elucidated in the following worked example. 

There are no official U.S. specifications for teUurium and producers pubUsh thek own standards. TypicaUy the producer specifies the weight and shape of the pieces, a screen analysis of powders, and a maximum content of certain impurities. 

Homogeneous molecular population for a wide range of macromolecules presenting variety of molecular weights and shapes ... 

In the preparation of suppositories, the proportion of base may be varied to maintain a suitable consistency under different climatic conditions, provided the concentration of active ingredients is not changed. The size of mold is fixed depending upon the weight and shape of the suppositories. The weight... 

Figure 4.3 Influence of weight and shape on the energy needed to run an electric efficient car.

Figure 11.6 indicates approximate /-values for some of the components in peppermint oil on a BPX-5 column this column selects mainly on the basis of molecular weight and shape. For example p-pinene has the same molecular weight as limonene but has a more compact shape and thus a lower /-value. Menthyl acetate has a higher /-value than menthol because of its higher molecular weight. 

Wade, T, Martin, N.G., and Tiggeman, M. (1998) Genetic and environmental risk factors for the weight and shape concerns characteristic of bulimia nervosa. Psychol Med 28 761-771. 

Ejection forces are relatively higher for roller compaction tablets, although similar to direct compression. Ejection forces are usually 100-400 N, depending on the tablet weight and shape, as shown in Figure 26. 

Factors affecting compatibility, in addition to polarity, are the size (molecular weight) and shape of the plasticizer. An example of good compatibility due to similar chemical structure (polarity, shape, size) is the oldest known plasticizer-... 

Ribosomal RNAs (rRNAs) are found in association with several proteins as components of the ribosomes—the complex structures that serve as the sites for protein synthesis (see p. 433). There are three distinct size species of rRNA (23S, 16S, and 5S) in prokaryotic cells (Figure 30.2). In the eukaryotic cytosol, there are four rRNA size species (28S, 18S, 5.8S, and 5S). [Note "S" is the Svedberg unit, which is related to the jnolecular weight and shape of the compound.] Together, rRNAs make up eighty percent of the total RNA in the cell. 

Microimpulse methods. Impulse methods have many shortcomings, primarily because of the considerable dissipation of energy required to produce an indentation of the sampler, this being dependent on the weight and shape of the sample, and preparatory treatment of its surface. 

The physical properties of amines depend in an important way on the extent of substitution at nitrogen. Thus primary amines, RNH2, and secondary amines, R2NH, are less volatile than hydrocarbons of similar size, weight, and shape, as the following examples show ... 

The diffusion constant D is a function of both molecular weight and shape. It can be measured by observing the spread of an initially sharp boundary between the protein solution and a solvent as the protein diffuses into the solvent layer. Once we know the value of the diffusion constant, we can combine the information with the sedimentation data and calculate the molecular weight of the protein. 

Calvin, M., and Philip, R. P. (1976). Possible origin for insoluble organic (kerogen) debris in sediments from insoluble cell-wall material of algae and bacteria. Nature 232,134-136. Cameron, R. S., Thornton, B. K., Swift, R. S., and Posner, A. M. (1972). Molecular weight and shape of humic acid from sedimentation and diffusion measurements on fractionated extracts. /. Soil Sci. 23,394 108. 

Since the first insulin PEGylation studies of Ehrart and Luisi, several investigations have been carried to improve the physico-chemical and biological properties of this hormone by site-specific or random attachment of one or more PEG chains with different molecular weight and shape. Although the array of events which determines changes in the in-vivo behavior of insulin are often difficult to pinpoint, these studies showed that the biopharmaceutical properties of the hormone are... 

So, permeability is proportional to the diffusion coefficient in the membrane and the partition coefficient between the membrane and aqueous phases, while being inversely proportional to the thickness of the membrane. The molecular weight and shape of the permeant are related closely to all of those characteristics. 

WHILE the chances are thot you ll never be attacked by anyone wielding a knife the Jiu-Jitsu defense against such a person is so easy that you cannot afford to neglect it. When practicing use a knife of the proper weight and shape, but have the blade covered by some protective sheath so thot there is no possibility of anyone... 

Starch acetate solutions exhibit viscosity effects characteristic of dissolved high polymers. Since the viscosity of a starch solution varies in relation to the size of the starch molecules, viscosity measurements have afforded a rapid means for following molecular breakdown, and, in addition, have provided information on the molecular weight and shape of the dissolved molecules. 

A frequent additional feature is a subjective distortion of body image. Although painfully thin, individuals will insist that they are too fat and/or that their abdomen, buttocks or thighs are too large. Their self-esteem is highly dependent on their body weight and shape they celebrate further weight loss as a laudable achievement. 

Gowers, S. G. and A. Shore (2001). Development of weight and shape concerns in the aetiology of eating disorders. Br J Psychiatry 179 236-42. 

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