Nine heat-resistant alloys were exposed to cycles of oxidation plus carburization. Each cycle consisted of 4 h of oxidation in air at 700 degrees C followed by 16 h of carburization in hydrogen gas (H-2) + propylene (C3H6) at 950 degrees C. The alloys were tested for 1, 3, and 5 cycles, and invariably were found to have undergone internal carburization. The rate of this process was measured with respect to cumulative carburization time, and the kinetics were found to be parabolic. Data from isothermal carburization of the same alloys were compared with rates found in the cyclic process. In general, the internal carburization produced by the 3- and 5-cycle runs was greater than that resulting from isothermal carburization. This was a result of a ''metal dusting'' attack of the alloys and increased carbon activities in their surface regions.

A double-blind trial was conducted which attempted to compare and contrast the therapeutic effects of haloperidol and thioridazine in a chronic schizophrenic population. The psychiatric use of these two drugs, one a butyrophenone, the other a phenothiazine, is discussed with reference to the management of this clinical population.

The clinical features of 100 patients with psychopathic personalities presenting to an acute psychiatric service are described. Neurotic symptoms were frequently found to co-exist with psychopathic traits. Fifty-three patients had abnormal electroencephalograms. The abnormalities were significantly negatively correlated with age, and positively with the occurrence of epileptic convulsions, but few other significant clinical correlates were found. It is suggested that an abnormal EEG may be positively misleading if misinterpreted as evidence of epilepsy or of an “organic” disorder. The medico-legal and therapeutic implications of this conclusion are discussed. It is suggested that environmental deprivation may be one of the factors responsible for the delay in electroencephalographic maturation so frequently found in psychopaths.

After briefly reviewing the principal features of the human E.E.G., some recently described E.E.G. phenomena and the literature on current clinical advances are summarized, including the use of the E.E.G. to determine brain death. The problem of computer analysis of the E.E.G. and the possible significance of studies on the cerebral evoked response are discussed. The discovery of “contingent negative variation”, for which important claims have been made, is described with reviewer's caution. The paper concludes with a summary of the origin of E.E.G. activity relevant to the needs of the clinician.

The author presents a survey of the literature, together with a study of the phenomena of déjà vu and depersonalization in a largely healthy population. He concludes that the déjà vu experience as elicited by a clinical type interview is common particularly in intelligent subjects of higher socioeconomic status. Well defined depersonalization experiences will also be elicited by clinical enquiry from subjects free from major psychiatric disability.

The motile species of diatoms in a largely non-motile association on grains of sand travel to the surface of the sand when buried, although they move more slowly and less often than species living in silt, and ascend each grain in turn. Diatoms on sand grains from a freshwater lake are found to migrate daily to and from the surface grains, whether in a natural daylight régime or in continuous darkness. They do not leave the surface when exposed to 750 lux of constant illumination although they will at 75 lux. Their movements help to keep them in the photic zone during the day.

Adhesive and tractive forces of diatoms have been measured by the bending of a glass fibre. The results show that motility depends on attachment to the substrate. Movement on girdle bands occurs when the raphe acts against lumps of trail substance. Resistance to shear stress in laminar flow through a capillary tube is found to be particularly high in large epipsammic spp., e.g. Amphora ovalis, and is related to strong adhesion. The mechanism of movement is discussed in relation to the physical properties of the raphe and trail.

This paper describes new microwave techniques employing the properties of N-type germanium diode switches. For applications requiring very high isolations, multiple switches are added in tandem. With proper spacing, they form antiresonant cavity circuits. In this case the isolations and insertion losses in db are directly additive. A switch is described which is normally ON and is pulsed OFF. Finally, details are given of a switch in a hybrid-tee configuration in which switching isolations of 50 db are obtained with an insertion loss of 0.7 db.