SUMMARY Oxidation of methyl linoleate was studied in a freeze‐dried model system based on micro‐crystalline cellulose. Oxidation was followed manometrically in samples adjusted to various water activities ranging from approximately 0 to approximately 0.6. Water was found (as determined from induction period and rate data) to have an inhibitory effect on the oxidation reaction, varying with water activity up to values of 0.5. Evaluation of the rate data indicates that the inhibitory effect of water is most pronounced in the initial stages of oxidation, including the period during which the hydroperoxide decomposition follows monomolecular decomposition kinetics. Possible interpretations of the observed water effect and its significance to the general problem of lipid oxidation in dehydrated foods are discussed.

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SUMMARY The oxidation of methyl linoleate catalyzed by various salts of cobalt was studied in a model system based on microcrystalline cellulose. The freeze‐dried model system was adjusted to various water activities, and the effect of water on the oxidation kinetics was determined using manometric measurements and measurements of diene conjugation. It was found that water had an inhibitory effect on the metal‐catalyzed oxidation of the fatty ester, as well as on oxidation in the absence of added metals. The kinetics of the reactions were evaluated in terms of the previously established hydroperoxide decomposition mechanisms. The effect of water on the metal‐catalyzed oxidation was found to exist in the monomolecular decomposition period as well as in the more rapid phase of the reaction, during which the hydroperoxide decomposition is known to follow bimolecular decomposition kinetics. The inhibition of the reaction by water is interpreted as due to deactivation of added, as well as of originally present, metal catalysts by hydration of the coordination shells; and also possibly as due to hydrogen bonding between hydroperoxides and water, and therefore to interference with the normal bimolecular decomposition reaction.

This study compared the relative efficacy of four popular methods of memory retrieval: hypnosis, “Guided Memory,” “Cognitive Interview,” and spontaneous free recall. These retrieval methods, tested in an academic setting, were paired with different intake methods, utilizing audio, visual, audio-visual, and reading inputs. All interview sessions, including hypnosis induction, were conducted individually and only free recall (as opposed to forced recall) techniques were used by the interviewers. The number of subjects' correct responses was converted to a percentage of the total of potentially remembered items. These data, through the use of a Treatment ö Block ANOVA, showed a statistically significant difference between intake methods but a nonsignificant difference between recall methods, suggesting that guided memory and cognitive interview techniques may be as effective as hypnosis in short term free recall. This study indicates that when contributing cognitive features are extracted, hypnosis by itself does not lead to further memory improvement Confabulations and distortions, though present in any type of reconstructed memory, are minimal when force, pressure, or persuasion is absent from the retrieval process.