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Two studies of information processing in normal human sleep are reported. In Experiment I it was found that subjects responded differentially in stage 2 sleep to “own name,”“other name,” and tone stimuli (decreasing in that order) as reflected in both the finger plethysmograph (FP)and heart rate (HR) and to some extent the EEG K-complex response, and similarly in REM sleep as reflected in the FP measure and to some extent the HR measure, but not in sleep stage 3–4. In Experiment II it was found that conditioned discrimination acquired during wakefulness persisted in sleep stage 4, as reflected in the FP and HR measures, and sleep stage 2, as reflected in the K-complex response, but not in REM sleep. Results are compared to other studies of information processing in sleep. It is concluded that the results appear to indicate differential availability of the mechanisms of long-term memory, short-term memory, and stimulus preprocessing in the various stages of sleep. The authors further noted a bifurcation of the autonomic nervous system in sleep into two discrete effector limbs: electrodermal and cardiovascular.

A modified version of the automated fluorometric determination of tyrosine by the nitrosonaphthol reaction is described, which was developed for the analysis of tyrosine in blood and tissues, and is simpler, more rapid, and more sensitive than earlier methods. Of the 50 compounds tested with this method, most of which were phenolic in structure, only para -substituted phenols with no other substituents in the aromatic ring, and 5-hydroxy indoles, gave appreciable fluorescence.

1. Aromatic acids were extracted from brain and liver of rats with phenylketonuria-like characteristics produced by administration of phenylalanine, either alone or in combination with p-chlorophenylalanine. The metabolism of the aromatic acids in these tissues was measured by gas chromatography. 2. At 1h after an intraperitoneal injection of l-phenylalanine (1g/kg) in 23-day-old rats, the phenyl-lactate concentration was 2.2μg/g in the liver and 0.43μg/g in the brain, and the concentration of o-hydroxyphenylacetate was 0.26μg/g in the liver. 3. Phenylacetate concentrations in brain and liver were 0.26 and 0.14μg/g respectively. 4. Suckling rats produced phenyl-lactate less rapidly than weanling rats, but accumulated higher concentrations in longer-term experiments. 5. Intraperitoneal injections of phenyl-lactic acid showed that this compound could directly penetrate the blood–brain barrier, and could produce similar brain/liver ratios of phenyllactate to those found after phenylalanine injection. 6. Qualitative and quantitative similarities in urinary excretion of aromatic acids between the rats used in this study and human patients with uncontrolled phenylketonuria indicate that a patient with a circulating phenylalanine concentration of the order of those achieved in the experimental animal may have aromatic acid concentrations in brain and liver comparable with those found in the rats used in the present study.

2,4-Dinitrotoluene (DNT) shows Group I explosive behavior, although it can be dead-pressed moderately easily. Its infinite diameter detonation velocity is approximated by D i (mm/μsec) = 1.96 + 2.913 ρ o' , The detonability and shock sensitivity of 3–10 μ DNT are near those of production lots of high-bulk-density nitroguanidine and DATB, respectively.

A semiautomated kinetic assay of phenylalanine 4-hydroxylase was developed and provided high sensitivity without radiochemical techniques. Dithiothreitol was used as a reductant to simplify the reaction mixture. The deproteination (dialysis) and tyrosine determination were carried out by an automated procedure using standard AutoAnalyzer equipment. The enzymatic activity in pCPA-treated and control rats was measured, and other possible applications of the procedure are discussed.

2,4-Dinitrophenyl derivatives of phenylethylamines have been applied to the sensitive quantitative analysis of phenylethylamines in biological tissues by gas chromatography and electron-capture detection. The minimal detectable amounts are about 0.1 ng. A rapid and specific cleanup procedure allows the injection of 10% of all the amines extracted from 200 mg tissues, so that as little as 20 ng/gm tissue can be determined. Amines with or without hydroxyl groups can be determined as the DNP-derivatives with equal sensitivity. The corresponding 3,5-dinitro-4-trifluoromethyl derivatives were also prepared and their chromatographic behavior is reported.

A knowledge of the Hugoniot of unreacted explosives is required to interpret transitional phenomena in explosives and to determine the shock sensitivity of explosives. The usual method employed to obtain the Hugoniot of a material is to perform a series of experiments which measure two of the following variables: shock velocity, particle velocity, pressure, and volume. However, there are drawbacks to this approach for porous (granular) explosives. Fortunately, computational methods have been developed which yield the Hugoniot of inert, porous materials when the Hugoniot of the non-porous material is known. If these computational methods can be applied to porous explosives, much work and expense can be saved. In this study, the authors have applied these computational methods to porous TNT for a range of densities from 1.60 to 0.98 g/cc. This method was confirmed by experimentally obtaining the Hugoniot for unreacted TNT at a density of 0.98 g/cc over the range of particle velocities of 0.350 - 1.720 mm/microsec and of pressures of 3.6 - 55.0 kbar.

Summary Studies with human platelet monoamine oxidase show that the enzyme contains two interacting catalytic sites. One site has a high affinity for phenylethylamine and its activity is noncompetitively inhibited by either benzylamine or tryptamine. However, benzylamine and tryptamine act as fully competitive inhibitors for each other and thus appear to be deaminated as a separate site. The Km for each amine was in good agreement with the KI determined when it was used as an inhibitor.

Rabbit platelets were found to contain both types A and B MAO activities. The specific enzymatic activity of rabbit platelet MAO was higher for the substrate serotonin than for phenylethylamine. The Km's for rabbit platelet MAO indicated that the MAO-B enzyme was similar to human platelet MAO and that both MAO-A and MAO-B enzymes in the rabbit platelet are similar to the corresponding forms in the rabbit brain. The drugs clorgyline and deprenyl confirmed the existence of types A and B MAO in the platelet and furthermore indicated that the type A form accounted for approximately 90% of the total enzymatic activity. Amitriptyline at low (micromolar) concentrations selectively inhibited MAO-B activity in both rabbit platelets and brain.

Tricyclic antidepressant drugs were found to inhibit human platelet MAO. The I50 for the inhibition by amitriptyline was 4 × 10 −6 M, 1.6 × 10 −5 M, and 2 × 10 −4 M when phenylethylamine, tryptamine, and benzylamine were used as substrates. Amitriptyline exhibited noncompetitive inhibition with the substrates phenylethylamine and tryptamine but competitive inhibition with benzylamine. Solubilization and partial purification of platelet MAO did not alter the inhibitory effects of tricyclics. Treatment of the partially purified enzyme with the chaotropic agent sodium perchlorate produced only a slight increase in the inhibition constant for amitriptyline. Our findings suggest that selective inhibition of phenylethylamine oxidation may mediate the antidepressant actions of tricyclics. In addition, our studies provide some evidence for the existence of multiple catalytic sites of MAO activity in the human platelet.

DNT shows Group 1 explosive behavior although it can be dead-pressed moderately easily. Its infinite diameter detonation velocity is approximated by detonation velocity (mm/micron sec) = 1.84 + 2.913 loading density. Its detonability and shock sensitivity are, respectively, near those of high bulk density nitroguanidine and DATB. A review of factors affecting detonability and sensitivity of a chemically homogeneous explosive is also presented.

The electromagnetic velocity (EMV) gage was used to investigate particle velocity vs time and peak particle velocity vs distance at several points in PMMA (polymethylmethacrylate) in the donor-gap arrangement of the NOL Large Scale Gap Test. The results obtained by the method agree favorably with previously measured peak particle velocities for gap distances from the HE-PMMA interface between 10 and 25 mm. At closer distances the particle velocity-time records are in good relative agreement with one dimensional hydrodynamic computations. The values of peak particle velocity found for distances less than 5 mm are not in agreement with the previous extrapolation to zero gap of the earlier data obtained for gaps > or = 10 mm. Consequently, a new tentative calibration for the close-in distance is presented. The study encountered a number of recording problems; noise in the records and poor system response. Steps taken to eliminate the noise and to improve the recording response are outlined. Also discussed are the theoretical behavior of the gage, factors influencing systems response, and comparison of real with predicted response. It was concluded that the EMV gage is a convenient and useful tool for measuring particle velocity vs time in non-conducting or weakly conducting media.

1. Phenethylamines were extracted from brain and liver of rats with phenylketonuria-like characteristics produced in vivo by inhibition of phenylalanine hydroxylase (EC 1.14.3.1) with p-chlorophenylalanine, with or without phenylalanine administration. To protect amines against oxidation by monoamine oxidase, pargyline was also administered. 2. β-Phenethylamine was the major compound found in brain and liver. β-Phenethanolamine and octopamine were also present, in lesser amounts, and the concentrations of these three amines paralleled blood phenylalanine concentrations. By comparison, tissues from control animals had only very low concentrations of these amines. 3. Small amounts of normetadrenaline, m-tyramine and 3-methoxytyramine were also found. 4. The inhibitors used, p-chlorophenylalanine and pargyline, gave rise to p-chlorophenethylamine and benzylamine respectively, the first via decarboxylation, the second probably by breakdown during extraction. 5. Distribution of phenethylamines in different brain regions and in subcellular fractions of rat brain cells was also investigated. The content of phenethylamine was highest in the striatum. 6. These findings are discussed in the light of changes occurring in human patients with uncontrolled phenylketonuria.