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The behavior of self-excited chatter after an excitation is studied by introducing the new idea of a multiple regenerative effect. This considers not only the effect of one turn before, but that of two or more turns before. The analysis explains well some characteristics of the chatter, such as the finite amplitude after the onset, and the generation of chatter marks. Increase of the stability at low cutting speeds is also discussed in terms of a resistive force due to the relative motion between work and tool.

Phenol soluble proteinaceous substance (PSPS) was extracted from the whole cell of E. coli using the Westphal's phenol-water method.The procedure was similar to that of the extraction of protodyne (Berger et al) excepting some difference in the starting materials of whole cell for extraction in the former and, in the latter, of the cytoplasma, previously isolated from the cell wall.The results in regard to the chemical and biological characteristics of PSPS were as follow : 1) PSPS consisted mostly of proteins ; small amount of hexose and ribose, none of desoxyribose.2) Using the Sephadex G-200 column chromatography the PSPS was separated into 3 fractions with the high absorption of 280 mμ.3) Molecular weights were determined by Andrews' method as having 150, 000 for Fr I, 30, 000 for Fr II and 10, 000 for Fr III, respectively.4) PSPS has an ability to induce the some degree of Shwartzman reaction in the rabbits, which was far less than that of endotoxin.5) Homocytotropic antibody was produced by the PSPS incorporated in alum-gel as adjuvant; reached the maximum titer at 3 weeks; remained the high titer at 4 weeks after the immunizationIn conclusion, PSPS looks like the protodyne as to the chemical characteristic except for the contamination with small amount of endotoxin, because of its relatively high contents of sugar and of inducible activity of the feeble Shwartzman reaction in rabbits in comparison with protodyne. From these results PSPS should be much more purifed by means of column chromatography to have an exclusively proteinaceous substance just like the protodyne.

In the previous manuscript, authors reported that PSPS consisted mostly of proteins with small amounts of hexoses and riboses ; that revealed and ability to induce feeble Shwartzman reactions in rabbits and to produce the homocytotropic antibody in rats with relatively high titers. In this paper, PSPS had another aspect of biological activity as an inhibitory effect upon the TdR incorporation into human leucocytes stimulated with PPD, streptococcal M-protein and SK-SD, respectively.The results obtained were as follows :1) PSPS was able to stimulate the human leucocytes of healthy subjects in 2 out of 7 persons in whom stumulation index (S. I.) revealed 3 and 13, respectively.2) On the contrary, PSPS inhibited the TdR incorporation into leucocytes stimulated with PPD, streptococcal M-protein and SK-SD when that was given simultaneously with those antigens to a large extent of showing more than 70% of percentage inhibition in an individual case.3) Of particularly curious thing was that in a case (donor T. K.) in which the PSPS obviously stimulated the leucocytes with an increased TdR in corporation, inversely that inhibited TdR incorporation with approximate 70% of percentage inhibitions when was given simultaneously with specific antigens.4) There was a trend toward more increment of percentage inhibition in such a condition that the PSPS was given simultaneously or 2 hrs before the antigen stimulations with PPD, streptococcal M- protein and SK-SD in comparison with that 2hrs after antigen stimulations, suggesting a possible involvement of competitive binding between the receptors for antigens and for PSPS.5) Trypan blue exclusion test was carried out in order to exclude the cytotoxic activity of PSPS upon the leucocytes with the resultant data of over 80% viable cells remaining at 3, 4 and 5 day cultures.Thus, though PSPS was able to stimulate those leucocytes with the increased TdR incorporations in a part of healty subjects, that inversely inhibibited the TdR incorporations when was stimulated simulutaneously with the specific antigens. The mechanisms underlying these mutable contradictory actions of PSPS upon the human leucocytes should be more clarified on the basis of its chemical purification and mutual competitive inhibition of cell surface receptors involved in the regulation of DNA synthesis in nucleus.

Production of myocardial lesions with sympathomimetic a mines was studied in rats. Subcutaneous administration of isoproterenol at the daily doses of 1.2mg and 0.7mg per kg for 14 days caused a marked diffuse myocarditis. The myocardial lesions were detected by electrocardiogram 1 week after the begin-ning of the administration. Norepinephrine, nor-fenefrine and phenylephrine did not show any pathologic change in the myocardium. The significance of the toxic effects of these a mines was studied.

In order to investigate the structural changes in alloys with different size and structure of small spherical G.P. zones and intermediate precipitates, measurement of X-ray small angle scattering were carried out at liquid nitrogen temperature for A1–4.4 at per cent Zn, AI-1.0 at per cent Ag, AI-5.0 at per cent Zn-5.0 at per cent Ag and AI-2.8 at per cent Zn-1.4 at per cent Mg alloys. Through the measurement of the scattering intensities before and after irradiation with doses of 3.2 ×1015 and 1.5 × 1016 n· cm−2 below 20 °K, the changes in size, volume fraction and size distribution were clearly detected. The Guinier radius decreased with irradiation for all of the specimens. The Porod radius of G.P. zones in the binary alloys also decreased, except the Al-Zn alloy containing small G.P. zones with short spacing. The integrated intensity, which is proportional to the volume fraction, slightly decreased for the binary alloys, and increased for the ternary alloys. The size distribution after irradia...

Small-Angle X-Ray Scattering (SAS) has wide application in the field of macromolecules, colloidal solutions etc., while its application to physical metallurgy is restricted. But the smaller particles than 100A in metals and alloys can be analysed better by the SAS method than by electron microscopy. It was Guinier who first introduced SAS techniques to this field. He had studied the structure of small heterogeneities, named Guinier-Preston Zones. They have the same crystallographic structure as the matrix solid solutions. But it is clear from the theory of SAS that this method can be applied to detect the heterogeneities of atoms in the non-crystalline materials, as glass materials.The advantage in the application of SAS is the fact that lattice strains cause only minor changes of the diffracted intensity.In this summarizing report, it is intended to describe what can be clarified by the SAS method. The determination methods of average particle size, particle number, solute concentrations inside and outside particles, size distribution, shape, the concentration gradient at the particle surface and spacial distribution of particles are described with the theoretical background and some examples.SAS has also been applied to the analysis of lattice defects, as agglomeration of vacancies and dislocations. The scattering intensities with these defects are much weaker than with clusters of solute atoms. As the undesired diffraction effects, double Bragg scattering, incoherent Compton scattering, temperature scattering and fluorescent radiation must be considerd in the quantitative analysis.

The mechanism of decomposition and its products were investigated by resistivity measurements and optical and electron microscopy. The existence of a new metastable phase (G') was established, besides the known Al6Mn and G phases. However, no sequence of precipitation was observed, in spite of the occurrence of metastable phases.The precipitation process seems to be mainly affected by the degree of difficulty in nucleation of these three phases. Accordingly, grain boundaries and dislocations can act as preferential nucleation sites and thus control the precipitation behavior of the alloys.

Experiments have been made to examine the effects of cold working on the rate of cluster formation and precipitation in Al-4%Cu or Al-1.8% Cu alloys with X-ray Laue Photographs, electron micrographs and measurements of micro-hardness. The correlation between cold woring and the excess vacancies retained in quenching was investigated with water quenched, air cooled and reverted specimens. The effects of cold working after aging at low temperature were also examined here.The experiments provided evidence that the formation of the less stable G. P. (1) and G. P.(2) is hindered, while the precipitation of the more stable θ' phase is accelerated.The rate of precipitationis more rapid in water quenched specimens than in air cooled, or reverted materials. The increased rate is due to the fact that the lattice vacancies which are more than the equilibrium are retained in quenching. The suppressive effects of cold working are most remarkable in water quenched alloys.The mechanism by which the rate of cluster formation is retarded may be due to two effects: one is the sweeping out of the quenched-in vacancies, which are necessary for solute diffusion, by the motion of jogs in dislocations during plastic deformation or the increase in the rate of annealing of quenched-in vacancies as a result of cold working; and the other is the formation of many smaller enriched clusters of solute atoms which are formed by the stronger binding interaction between solute atoms and lattice defects introduced by cold working.

In our studies with drug combinations, we searched for mixtures which would enhance the effectiveness of the related active substances. Ethenzamide was found to possess a specific suppressive effect on the gastric damage induced by aspirin. Such effect could not be demonstrated in analgesic agents such as salicylamide, bucetin, acetaminophen and phenacetin. The combination of aspirin with ethenzamide had a potentiating effect on analgesic activity and reduced motor incoordination and loss of righting reflex. We calculated the safety margins of various ratios of combinations and concluded that the best was aspirin and ethenzamide at a ratio of 2:3.

The healing process of acetic acid-induced gastric ulcer in rats was observed with an endoscope for 365 d after ulcer induction. The ulcers were induced by acetic acid solutions of various concentrations (2.5 (I), 5.0 (II), 10 (III) and 20% (IV); 0.05 ml). On day 3, a positive correlation was observed between the ulcer index (UI) and the concentration of acetic acid solution. On day 365, cumulative healing rates in groups I, II, III and IV amounted to 100, 100, 58.3 and 51.7%, respectively. The cumulative relapse rates in groups I, II, III and IV were 0, 13.6, 66.7 and 58.6%, respectively. Significant correlations were observed between initial UI values and cumulative healing or cumulative relapse rate. On day 365, rats were divided into two groups, a healed group and non-healed group, and the gastric mucosal prostaglandin I2 (PGI2) level was measured by bioassay. The PGI2 level around ulcers in ulcer-induced rats was higher than in normal rats, and it was higher in non-healed rats than in healed rats. Moreover, the PGI2 level was higher in those groups which showed a higher cumulative relapse rates. The above results indicated that the initial ulcer size and the PGI2 level around the ulcer might correlate to ulcer healing or exacerbation.