Carbohydrate and protein metabolism were examined in rainbow trout, Oncorhynchus mykiss, fitted with mini-osmotic pumps which maintained plasma cortisol levels at approximately 100 or 200 ng∙mL−1 for 10 d. Plasma glucose, lactate, and protein levels were unaffected by 10 d of cortisol administration, despite a significant elevation in plasma cortisol. Plasma amino acids in cortisol-treated fish (1023.8 ± 90.7 μg∙mL−1) were significantly elevated compared with shams (716.7 ± 68.5 μg∙mL−1) after 9 d. Liver glycogen content was significantly reduced by cortisol treatment. The activities of the liver enzymes assayed were unchanged; likewise the flux of radioactive substrates to radiolabeled CO2, glucose, and protein in isolated hepatocytes was unaffected in trout with chronically elevated cortisol compared with shams. The glucose replacement rate (Ra) was unchanged after 2 wk of cortisol treatment. These data do not support the purported role of cortisol as a glucocorticoid in rainbow trout. While chronically elevated cortisol may increase the supply of plasma amino acids, the hormone does not appear to alter the manner in which this potential gluconeogenic substrate is metabolized. The absence of other stressors may be partially responsible for the differences between this study and others in the literature.

The chlorines in chlorosulfonated polyethylene have been characterized by kinetic analysis according to the method of Salomon. It is found that 2.7% of the total chlorine is primary, 89.8% secondary, 3.5% tertiary, and 4% is sulfonyl chloride. These results are in accord with statistical calculations based on a polyethylene model containing the same methylene‐to‐methyl group ratio as the polyethylene precursor. The types and approximate quantities of dichlorides in the chlorosulfonated polyethylene have been determined by reactions with potassium iodide and zinc dust

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Neoprene polymer chains are cross-linked between active chlorine sites on the chains. There are two types of active sites of different reactivity. It is necessary to use more vigorous curing conditions to actuate the less reactive chlorine. The polymer develops cross-links while aging as a latex as well as during cure, and the decline of tensile strength with latex age may be inversely correlated with the amount of cross-linking during aging. The decline of tensile strength can be prevented by compounding with bis (diethylthiocarbamyl) disulfide. The calculations of the swelling data are not so complete as might be desired, primarily because of difficulty of measuring and interpreting the molecular weight of high-conversion polymers and to some uncertainty in determining μ. It is felt that the qualitative observations are justified, and that they serve to define both the technically important effect of film structure on tensile strength and the mechanism of cure.

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