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The nuclear DNA content of the emu relative to that of the chicken has been measured by microdensitometry of Feulgen-stained erythrocytes and found to be 1.236±0.028 which is within the range of values previously found for birds. The statistical method for obtaining this value and its standard error is given in full.

The dolichol of rat liver was labelled by injecting [4S-3H]mevalonate, the precursor of cis-isoprene residues, into partially hepatectomized animals. The optimum conditions for labelling the dolichol were to inject the animals with radioactive mevalonate 48h after hepatectomy and to kill them 12h later. The concentration of radioactive dolichol was five times as great in regenerating rat liver as in normal liver. The highest concentration of radioactive dolichol was found in the crude mitochondrial and nuclear-debris fractions of the cell. The crude microsomal fractions also contained radioactive dolichol, but at a lower concentration.

Neisser, Hoenig, and Goldstein (1969) reduced the “stimulus prefix effect” (diminished recall of seven digits preceded by a redundant prefix) when the redundant prefix and the recall digits were produced by different speakers. In the present studies, similar results were obtained using one speaker only, but with the prefix and recall digits spoken separately in different utterances and combined by tape splicing. The results support a hypothesis concerning the perception of intact, wholistically organized articulatory units. A second hypothesis, also based on the idea of intact articulatory units, was tested.

Endogenous dolichol was shown to function as a natural acceptor of mannose residues by using regenerating rat liver containing [3H]dolichol. When subcellular fractions from this liver were incubated with GDP-[14C]mannose a double-labelled lipid, which represented 30% of the total [14C]mannolipid, could be isolated. This lipid was shown to be identical with the dolichol phosphate mannose formed from exogenous dolichol phosphate, by chromatography, stability to alkali and by chemical cleavage to mannose and dolichol derivatives. It was formed by the rough endoplasmic reticulum and mitochondria. If it is concerned in glycoprotein synthesis this would suggest that it functions in the formation of both secreted and mitochondrial glycoproteins. When both the dolichol and retinol of rat tissue were radioactive they made similar contributions to the synthesis of the lipid by liver microsomal fractions and intestinal epithelial cells.

✓ Two cases of cervical fracture-dislocation causing neurological deficits in patients with ankylosing spondylitis are presented. Review of the literature shows that these patients have a higher incidence of neurological deficits (70%) than comparable patients without ankylosing spondylitis (44%). Predisposing factors and treatment are discussed.

In some species of polygynous songbirds, males assist in feeding nestlings of their first (primary) female but ignore offspring of subsequent (secondary) mates. A number of adaptations important in minimizing the disadvantages of a secondary status in female Bobolinks ( Dolichonyx oryzivorus ) have been discovered. In Bobolinks, clutches of secondary females are significantly smaller than those of primary females, thereby adjusting brood size to correspond better with food delivery capabilities of secondary hens. Commencement of incubation with deposition of the penultimate egg allows additional brood size adjustment, for the resulting hatching asynchronism promotes efficient culling of the late-hatching chick in times of food shortage, without endangering the entire brood. Secondary females differ from primary pairs in food exploitation techniques by capitalizing on insects found close to the nest and by showing less discrimination in food selection. Such behavior permits compensation in the rate of food delivery trips to secondary nestlings so as to equal the tempo maintained by both members of the primary pair, yet results in quantitative disparities in food brought to primary and secondary nestlings. Flexibility in male feeding responses, resulting in partial male assistance at secondary nests in situations where secondary brood size is exceptionally large, is also important in helping to maximize the reproductive performance of birds engaging in this mating strategy.

1. Prostaglandin E1 increases sodium transport as measured by short circuit current (SCC) across isolated frog skin whereas calcium, added to the external Ringer fluid, decreases sodium transport. To help establish the site of action of prostaglandin the possible interaction of these two agents on sodium transport has been examined. 2. The effect of a standard dose of prostaglandin (0·5 × 10-6 M) on the short circuit current was tested on paired skins with either zero or high calcium (22·4 mM) in the external Ringer fluid. In ten experiments the responses to prostaglandin (expressed in μA/cm2) were not significantly affected by external calcium. 3. In another series of experiments the chelating agent, EGTA, was included in calcium-free external Ringer in order to promote greater depletion of skin calcium. The response of these skins to the standard dose of prostaglandin was of the same order of magnitude as that of control skins. The response was not sustained in contrast to that of normal skins and skins in high-calcium fluids. 4. In a further series of experiments the reverse procedure was adopted whereby the response of the skin to low and high doses of calcium in the external Ringer was recorded in control conditions and when the skin had responded fully to twice the standard dose of prostaglandin. In addition, the calcium-sensitive current was calculated for each skin in both circumstances. The latter was unchanged on addition of prostaglandin, and graded doses of calcium caused the same degree of inhibition of the short circuit current. 5. The results show no interaction between external calcium and prostaglandin and also no need for external calcium in prostaglandin stimulation of sodium transport. 6. The findings do not support the concept of chelation by prostaglandin of calcium from critical sites on the skin as the primary mechanism of its action on sodium transport. The results closely parallel those of a similar type of study into the relationship between vasopressin and external calcium on frog skin also. 7. When frog skin has responded fully to either prostaglandin E1 or vasopressin, it shows no response to the other, although removal of calcium from the external Ringer fluid causes a further increase in short circuit current. 8. Vasopressin causes a further increase in short circuit current in skins treated with prostaglandin F1α. Prostaglandin F1α may be a weaker agonist on frog skin than either vasopressin or prostaglandin E1.

The photo-oxidation of unstabilised polyvinylchloride has been shown to be sensitive only to the ultraviolet region of xenon-arc radiation, and the rate of oxidation as determined by an infrared spectrophotometer is approximately linear with radiation intensity. Since both spectrum and intensity of the xenon arc closely simulate terrestrial solar radiation, PVC has been examined as a simple monitor of ultraviolet radiation for use in characterising outdoor sites at which the durability of building materials is assessed. PVC films have been exposed at London, Melbourne, and Pretoria and the extent of oxidation compared with solar radiation recorded at the sites; in the case of Melbourne the extent was also compared with ultraviolet radiation.

SummaryAn enzyme system capable of catalyzing the biosynthesis of taurine in vitamin B6-deficient rats has been demonstrated. This activity was constant in liver even after rats had been fed the B6-deficient diet for 5 weeks. The CSA decarboxylase of rat liver was shown to be significantly reduced after 5 weeks of B6-defi-cient feeding. The significance of this enzyme system to the animal is discussed.

Two new antimetabolites of biotin were isolated from culture filtrates of Streptomyces lydicus : β-methyldethiobiotin and β-methylbiotin. 14 C-biotin or 14 C-pimelic acid was not incorporated into either of these antimetabolites by the growing culture. Neither of the compounds could substitute for the biotin requirement in Saccharomyces cerevisiae . Both compounds had a strong and rather specific antimicrobial effect against mycobacteria. Their antimicrobial activities were reversed by biotin. Both compounds had an affinity for avidin.

Anisole has been brominated using a sequence of brominating reagents generated by the reaction of a series of 4-substituted N-bromoacylanilides 4-RC6H4NBrAc (R = Ph, H, Cl, and NO2) with a series of carboxylic acids R′COOH (R′ = CF3, CCl3, CH2Cl, and CH3). The isomer distributions of the bromoanisoles produced have been measured for each N-bromoacylanilide–carboxylic acid pair and their variation with both the structure of the N-bromoacylanilide and the carboxylic acid provides a useful basis for a discussion of the mechanism of the bromine migration.

Observation of a bidimensional crystal of dislocation lines in sodium chloride In single crystalline NaCl crept at high temperature, we have observed a hexagonal lattice of etch-pits corresponding to a bidimensional crystal of dislocation lines. It is proposed that the type of crystal and its parameter depend on the shape and size of the cell which encloses the dislocations.

(1962). Some Aspects of Beer Colloidal Instability. Proceedings. Annual meeting - American Society of Brewing Chemists: Vol. 20, Proceedings of the Annual Meeting 1962, pp. 30-39.

Four kinds of word strings were heard behind masking noise in a speech-perception experiment. There were ordinary sentences (strings), semantically anomalous “sentences” (strings) and scrambled versions of each, called scrambled ordinary and scrambled anomalous strings. Words were systematically erased from each string such that string length varied from one to (all) five principal words, making a 4-string types × 5-string lengths design. All strings were rated by other S s on scales of meaningfulness or grammaticality. Some results were: (a) ordinary sentences were heard better through noise and rated as more grammatical and as more meaningful; (b) for all three measures the ordinary-string scores diminished relatively less or not at all as a function of increasing string length; and (c) the anomalous strings were rated as more grammatical than the scrambled ordinary strings, but the scrambled ordinary strings were rated more meaningful and were heard relatively better.

Two classes of frameshift mutations, (+) types and (−) types, have been isolated in the C gene of the histidine operon of Salmonella typhimurium. All of the (+) type and (−) type mutants are polar, i.e. they have lost C gene function and have reduced amounts of the enzymes corresponding to the genes beyond the C gene in the histidine operon. In nonsense suppressor-free strains, prototrophic double mutants carrying two frameshift mutations of opposite sign, (+ −) types, are all non-polar. In a nonsense suppressor-carrying strain, several polar prototrophic revertants of a frameshift mutation have been isolated. These polar strains become auxotrophic when the nonsense suppressor is removed. As discussed in the paper, all of these results were predicted by the hypothesis (Whitfield, Jr., Martin & Ames, 1966) that frameshift mutants are polar because they generate nonsense codons.

From experience with the PACT-1 Advanced Coding Technique as used on the IBM Type 701 Data Processing Machine a comparison is made between this coding system and 'machine language' coding with reference to coding time, number and types of errors, 'debugging' time and experience needed by the coder. In addition there are suggestions as to improvements that can be made on future systems and comments substantiating decisions made while writing the specifications for the system. (Author)

Unstabilised PVC has been photo-oxidised by exposure to xenon-arc radiation from which shorter wavelengths had been removed by a series of filters. The wavelength sensitivity was found to correspond approximately to the complete ultraviolet region of the solar spectrum, maximum photo-oxidation rates occurring at about 370 nm. Solar radiation data for Melbourne have been presented to show that variation in the ultra-violet component with time of day and season is unimportant, to the extent that global radiation data may be utilised to characterise an exposure site with respect to the rate of photooxidation of PVC at that site.

Compared with ternary sets comprising two distinct conventional machines, i.e. a pump and a turbine, reversible pump-turbine units permit considerable reduction in the capital cost of pumped storage schemes provided power demands for pumpwise and turbinewise operation are similar and provided also that time of transition between modes is not a decisive factor. On the other hand, reversible sets rotating either way pose several problems, a major one being the best way to effect pumpwise start-up, more especially when unit power is high. A number of possible procedures are examined and, in each case, advantages, disadvantages and application constraints are stated. Start-up procedures available may be classified as in Figure 1 (table). From the turbine standpoint, start-up may be carried out with the runner either wet or dry. Wet runner start-up is clearly the simpler of the two, although high starting torque is required to overcome the drag of the water. Dry start-up has the disadvantage of requiring expensive compressed-air equipment for dewatering the runner. When unit power is large, the majority of the start-up procedures call for a dry runner. The curves of Figure 2 show the general shape of the variation of pump-turbine drag torque with speed of rotation for wet and dry runners. These curves also point up the advantages of supplying oil at the thrust bearing. Choice between wet and dry modes depends largely on torque available and torque required. As for the choice of the best start-up procedure for a reversible unit, this is by no means a simple matter since it depends on a large number of criteria, the most important being as follows : (i) Characteristics of the unit to be started up, i.e. power, inertia, driving couple, drag couple, reactance, time constants, etc. (ii) Characteristics of the network : short-circuit power, acceptable voltage drop, line and transformer design, etc. (iii) Times allowed for changing from pumping to generation and vice versa. (iv) Number of units required for turbine and pump operation. (v) Local conditions on site e.g. ease of installation of a special unit or possibility of connecting up with a unit in a neighbouring plant suitable for back-to-back start-up. When technically feasible, direct synchronous start-up is the simplest, most economical procedure. However, the present trend towards increased reversible unit power seems likely to create problems. These will be concerned not only with the design and construction of the machines but also with network operation. Such problems may lead to preferential use of other start-up procedures. Start-up under reduced voltage may sometimes have advantages. This is an economical method (especially when reactance coils are used for voltage reduction) which is well suited to fast machines with low start-up reactance. However, use of this method should be confined to machines with low drag torques. Asynchronous start-up motors on the same shaft are suited to most cases. However, this is an expensive solution especially if the plant is made up of several sets. None of the other methods are valid except in rather special cases. However, it is worth noting that progress with the static converter may make this technique competitive with others in cases where schemes use large numbers of sets. No method is perfect and for a given problem several solutions are possible.

In a crystalline element the scattering of long wavelength neutrons by a point defect and an atom are known to be identical. However, when lattice distortion around the point defect is also considered, this is no longer true; in particular the scattering of a point defect is now anisotropic and varies with wavelength. An expression for the cross section of a defect in a relaxed lattice has been derived and applied to f.c.c. and b.c.c. lattices, and in greater detail to copper and molybdenum where the magnitude of the relaxation around defects is known. It has been found that the scattering cross section is appreciably altered by the relaxation of the surrounding atoms, and in particular from those that are nearest neighbours to the defect. A neglect of this relaxation in the interpretation of a neutron scattering experiment could lead to an error of an order of magnitude in an estimate of the number of defects. Also a study of the variation in cross section with wavelength or scattering angle, wh...

This paper describes a theoretical and experimental analysis of the behavior of simple beams bent by a central load while freely supported at each end. Both plane strain and plane stress conditions and the effect of friction at the beam supports are considered. Materials tested are SAE 4130 steel and titanium 6Al-4V alloy. It is concluded that in beams, whose length between supports is at least 25 times their thickness, the load required to effect deflection is increased by the amount required to overcome friction, but does not affect the circumferential strain at midspan. Theoretical methods of analysis correlate well with experimental results and allow the computation of stresses and strains from the beam geometry and true tensile curves of the materials.

SUMMARY A computer-based system is described for both the convenient storage and retrieval of data obtained from a large epileptic seizure patient population. Several examples of displays of data recall in three-dimensional histograms forms are presented. With a large number of stored patient records, more varied relationships should be possible, with a correponding increase in significance. RESUME On decrit un systeme utilisant un computer et permettant a la fois le stockage convenable et le reperage des donnees obtenues a partir d'une vaste population d'epileptiques. Plusieurs exemples de representation des donnees par des histogrammes tridimensionnels sont presentes. Si les dossiers stockes sont tres nombreux, on doit pouvoir etablir des relations entre des parametres plus varies, et rendre ainsi les resultats plus significatifs.