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Suppose F is an additively written free group of countably infinite rank with basis T and let E = End(F). If we add endomorphisms pointwise on T and multiply them by map composition, E becomes a near-ring. In her paper “On Varieties of Groups and their Associated Near Rings” Hanna Neumann studied the sub-near-ring of E consisting of the endomorphisms of F of finite support, that is, those endomorphisms taking almost all of the elements of T to zero. She called this near-ring Φω. Now it happens that the ideals of Φω are in one to one correspondence with varieties of groups. Moreover this correspondence is a monoid isomorphism where the ideals of φω are multiplied pointwise. The aim of Neumann's paper was to use this isomorphism to show that any variety can be written uniquely as a finite product of primes, and it was in this near-ring theoretic context that this problem was first raised. She succeeded in showing that the left cancellation law holds for varieties (namely, U(V) = U′(V) implies U = U′) and that any variety can be written as a finite product of primes. The other cancellation law proved intractable. Later, unique prime factorization of varieties was proved by Neumann, Neumann and Neumann, in (7). A concise proof using these same wreath product techniques was also given in H. Neumann's book (6). These proofs, however, bear no relation to the original near-ring theoretic statement of the problem.

A comparative statistical study of the trigeminal mesencephalic nucleus in 30 cats, 10 rats, 2 monkeys and 2 slow lorises has been presented. In contrast to previous results which show great discrepancies in neuronal counts in all species, and even in individuals of the same species, uniformity of estimates has been achieved by use of accurate counting methods, and clear definition of the parameters of this nucleus.

Following several reports on the possibility of harmful effects from sonar diagnosis, a detailed study has been effected to attempt to ensure the safety of clinical procedure. The emphasis in this work was with obstetric applications, such as diagnosis of pregnancy and foetal cephalometry, in which the developing foetus may be harmed. Mice were chosen as suitable experimental animals because of their large litter size, which allows good statistical analysis, and short gestation period. The range of peak ultrasonic intensities used was from 20 W cm−2 to 490 Wcm−2, mostly being well above that commonly used in clinical practice. Other dose parameters, such as time-average intensity, pulse length and total radiation time, were also vastly increased. Despite the use of these large doses no significant hazard, such as high incidence of abnormality rate, was found.

Lucan, fine poet though he be, is yet one of the most faulty and incalculable of the whole recalcitrant tribe. At the very outset we are surprised by a monstrously fulsome dedication to Nero of a work apparently devoted to a vilification of the man on whose amazing career Nero's empire is founded. Satire being quite out of the question, we must suppose that, despite his republican sympathies, Lucan, recalled as Suetonius says from Athens and received with marked favours, felt some acknowledgement required. At the worst we may regard it as a prudent step to forestall any treacherous slave-copyist, or delator who might have heard a partial recitation; and after Seneca's disgrace in 62, in which year the separate publication of books i–iii indicated by Vacca may have occurred, caution would be still more needful. To the same precaution it may be due that, in the poem proper, anti-Caesarian bias is not immediately apparent. The initial attitude seems impartial: general causes are mentioned; we get the plain statement:Quis iustius induit arma, Scire nefas; magno se iudice quisque tuetur: Victrix causa deis placuit, sed victa Catoni;and even some hesitation by Caesar himself, who, at the Rubicon, confronted by the Genius of Rome, exhibits terrors equal to any recorded of pious Aeneas; though after this he is consistently resolute, and is soon credited with a savage desire for bloodshed2 quite inconsistent with his reported actions and with history.

1. The descriptive anatomy of the tendinous component of the subclavius muscle is amplified. 2. The subclavius tendon comprises a shorter, medial pars libera, continuous with a longer, narrower, more lateral pars paramuscularis. This last may be prolonged further laterally by two or three tendinous fasciculi. 3. Both parts of the subclavius tendon are constant. By tenodesis they provide, on the average, one and a half to two inches of material eminently suitable for employment in the functional replacement of a damaged costo-clavicular ligament.

Plane-wave ultrasound at certain dosages can cause a statistically significant increase in the rate at which tissue re- generates to replace that lost after injury. The experimental model used in this study is the replacement of tissue in the pinna of the ear of a rabbit after the removal of tissue of area 1 cm2 through the full thickness of the ear. The regenerate consists of skin and its derivatives and elastic cartilage. The method of irradiation and the effects of a range of dosages on the rate of tissue replacement are described. Experimental evidence indicates that the growth rate increases found are not due to thermal effects caused by ultrasound; it is thought that a mechanical factor, streaming, may be involved. Electron microscopic studies show changes in the irradiated tissue that may be interpreted as indicating an increase in protein synthesis and temporary interference with the polymerization of collagen precursors. Autoradiographic investigation of 3H-thymidine uptake shows that the rate of synthesis of DNA in the regenerating tissue is increased by treatment with ultrasound. ISTROUL-CTIOX HERE have been several reports that ultrasound at certain dosages can increase enzyme activity (l), (2) and thus generally increase metabolic ac- tivity. In plants this effect stimulates seed germination and the growth rate of young seedlings (3), (4). This stimulation of plant growth suggested the use of ultra- sound as a possible stimulant of tissue growth in animals. The control of regenerative growth, i.e., the replacement of lost tissue, is clinically important in the treatment of injuries and in post-operative care. It is possible to stimulate growth by systemic means, for example, by the repeated injection of anabolic hormones (5), but such treatment affects other sites as well as the regenerate and can produce undesirable side effects. The direct

Utilization of intravenously administered oligosaccharides was tested in postsurgical patients by infusing them simultaneously with glucose and amino acids. Thirty two patients were infused with one of two parenteral regimens for four-day periods. Twenty-two patients received a nutritional regimen providing 46 g glucose, 32.5 g amino acids, and 45 g oligosaccharides per liter, while the remaining ten patients received the same solution without oligosaccharides. Patients infused with the test solution received an overall four-day mean +/- SD of 106 +/- 24.2 g oligosaccharide per day. The mean overall four-day excretion of total glucose (free plus oligosaccharide bound) was significantly higher (P less than 0.001) in patients infused with oligosaccharides (46.1 +/- 29.0 g/d) than in reference patients (1.19 +/- 1.20 g/d). Of the total carbohydrate excreted in patients receiving oligosaccharides, 11.3 +/- 13.1 g/d were glucose, 14.8 +/- 13.1 g/d were maltose plus maltotriose, and 20.8 +/- 19.3 g/d were oligosaccharides of maltotetraose size or larger. Although overall utilization of infused oligosaccharide for all patients was only 58.5% +/- 23.1%, three of the patients showed unexpectedly good utilization (94.6% +/- 1.24%).

Two longitudinal studies were undertaken to measure the naturally occurring coagulation inhibitors, protein C and protein S, in females who were either pregnant or who were undergoing hysterectomy. Functional and immunological protein C and free protein S were assayed. During pregnancy, protein C levels remained unchanged except for a small increase in protein C antigen at 28-32 weeks gestation. The free protein S fell significantly and progressively during pregnancy, although only in about one-third of patients did the level fall below the normal range. In the hysterectomy study, a significant fall in protein C occurred on days one and three after surgery but had returned to normal by the time of discharge (days 7-10). A small rise in free protein S was observed at time of discharge, but this factor was otherwise unchanged. We conclude that the changes observed may contribute to the hypercoagulable state which is associated with pregnancy or major surgery.