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A beryllium-walled cryostat is described which allows collection of nearly a full sphere of accurate three-dimensional X-ray diffractometer data at liquid-nitrogen (LN2) and liquid-helium (LHe) temperatures. Cryogen consumption is 0.3–0.4 liters of LHe per hour at 30°K and 0.1–0.2 liters of LN2 per hour at 78°K. The specimen is mounted on a copper block, the temperature of which is controlled to within 0.1°. Measurements with a powder sample of TbVO4 show that at 33°K the specimen temperature is within 2° of the temperature of the copper block. The cryostat has been used for the collection of several low-temperature data sets. Some special modifications in data-collection and data-processing software are described.

The distribution of the nuclei of chromium hexacarbonyl Cr(CO)6 in the crystalline state was refined from neutron diffraction data at 78K. It was found that diffraction by the aluminum walls of the cryostat used for low-temperature measurements was superimposed on the diffraction peaks of the crystal, and a method was derived to correct for this effect. Extinction was rather severe, and the correction formulae recently derived by Becker & Coppens [Acta Cryst. (1974). A30, 129-153] were applied successfully in the least-squares refinements. The Cr(CO)6 octahedron is significantly distorted in the crystal, but no significant differences were found between chemically equivalent bond lengths. The average values, directly derived by a least-squares procedure from the observed structure factors, and corrected for riding motion around chromium, are: C r -C= 1.918 /~ and C O = 1.141 A. These values show that the carbonyl groups are less strongly bonded to chromium than in the related complex benzene chromium tricarbonyl, which is consistent with the larger electronegativity of the carbonyl groups, compared to benzene.

The stability of ABH antigens in blood samples from five donors and stored over a period of 416 days has been investigated. The stability of PGM and AK isoenzymes in stored blood samples of five separate donors has also been investigated over a period of 72 days and 122 days respectively. The ABH antigens were found to be stable, the PGM isoenzymes were found to be less stable than the AK isoenzymes which persisted for approximately 100 days.

The preparation of lithium fluoride with thermoluminescence properties suitable for use in radiation dosimetry has been investigated. Variants based on magnesium and titanium additions have been prepared and examined from the viewpoint of activator concentration, role of secondary impurity and purity of the lithium fluoride starting material. The following properties were examined, impurity distribution and luminescence distribution within the crystal, emission spectrum, dose response characteristics and optical absorption. A sensitive thermoluminescent preparation may be obtained by the addition of magnesium alone to a readily available source of lithium fluoride.

A simplified N Ach measure predicts preferences for immediate reward content (among men), even when some of its correlates are controlled; but the same is not true of television content.

The generation of a plasma by fission‐fragment ionization of noble gases is reported. The experimental data consist of steady‐state current‐voltage (I‐V) characteristics obtained with ceramic‐metal ionization tubes which were operated in the high neutron flux region of a nuclear reactor. The observed dependence of I on V½ for applied potentials

(1971). Copper Price Behaviour and the London Metal Exchange. Applied Economics: Vol. 3, No. 2, pp. 99-113.

An account is given of the general structure of the body skeleton of the spatangid larva. A considerable change occurs in the skeleton as the larva increases in size, some parts being absorbed and new parts appearing. Of particular interest is the replacement of the anterior transverse rod by the ventral horizontal rod.The skeletons of larvae, young stages to late stages, ofEchinocardium cordatum, E. flavescens, Spatangus purpureus and Brissopsis lyriferaare described. The larvae ofEchinocardium and Spatangusare, in essentials, very similar; that of Brissopsis differs greatly from them. A striking difference is that in Brissopsis the ventral horizontal rod arises from the postoral arm and anterior to the anterior transverse rod, in the other two genera it arises from the body rod posterior to the anterior transverse rod.The replacement of the anterior transverse rod by a ventral horizontal rod is probably normal in clypeastroid larvae also.

The tendency to psoriasis is latent, requiring a causative constellation before lesions become evident. Large, coherent scales which reveal dull, reddish papular lesions when removed are characteristic. Some 29 unusual forms of psoriasis have been differentiated; the intertriginous type may be the most difficult to diagnose. Psoriasis is treated topically and systemically and with physical therapy.

Determinations of primary ? and secondary ? ionization coefficients in helium at pressures p0 near to atmospheric and low values of E/p0 (E is the electric field) show that ?/p0 = f(E/p0) and ?/? = (E/p0) for 30 < p0d < 730 cm torr. The results obtained for ?/? and its dependence on E/p0 are shown to be adequately accounted for on the basis of the assumption that the predominant secondary ionization process in helium at high pressures is the destruction of metastable states in the gas with the consequent production of non-resonance photons which liberate secondary electrons at the cathode.

PYELONEPHRITIS is a common and often severe complication of diabetes mellitus. It is generally believed that pyelonephritis occurs more frequently among diabetic than among nondiabetic persons.1 2 3 Unfortunately, most of the analyses of the relation of diabetes to susceptibility to infection of the urinary tract are obtained from hospital and autopsy experiences. From these studies, it cannot be determined whether diabetic patients are intrinsically more susceptible to infection, or whether they have more infections of the urinary tract because they are more likely to have been catheterized, or in other ways to have undergone instrumentation, or whether coincident bladder dysfunction or . . .

The three species of gregarines described in the present paper—Monocystis cambrensis sp.nov., M. lanceata sp.nov. and M. elongata (Phillips & Mackinnon, 1946), Loubatières, 1949—are all parasites of British earthworms. The observations upon which these descriptions are based form part of a larger survey of the monocystid fauna of several British earthworms. The methods used are fully described in a previous paper (Rees, 196).

An electronic double flash unit has been constructed to measure photographically average linear velocity of blood flow in the bulbar conjunctival vessels of the human eye. Two exposures on the same photograph separated by a predetermined time delay (adjustable from 2 to 200 msec) permit computation of velocity from the displacement of red cells per delay time. The equipment is small and mobile, the procedure innocuous.

The present paper is concerned with the description of six species of gregarines which are all parasites of British earthworms; they are: Apolocystis herculea (Bosanquet, 1894), A. lavernensis sp.nov., A. perfida sp.nov., A. rotaria sp.nov., A. spinosa sp.nov., A. villosa (Hesse, 1909) Cognetti, 1923. The observations upon which these descriptions are based form part of a larger survey of the monocystid fauna of several British earthworm species from the Cardiff area. The methods used are fully described in a previous paper (Rees, 1962).

The species of Astomatous ciliates of the genus Metaradiophrya dealt with in the present paper inhabit the intestine of three species of earthworms. They are, together with their hosts, as follows

Studies of electron density are reported for a quiescent neon‐argon gas plasma generated by fission fragments in the core of a nuclear reactor. Reaction kinetic equations for the various ionic and excited species are solved self‐consistently with electron‐energy balance equations to yield values of electron density and temperature. It is shown that for containers of diffusion length of about 1.6 mm or greater, there exists a maximum value of electron density at a total gas pressure p≈90 Torr and [Ar]/[Ne]≈10−4; the dominant ion in this case is the atomic Ar+ ion. At low values of neutron flux (∼1010 cm−2 sec−1) and electron density (∼1010 cm−3), the electron temperature is computed to be at or near the gas temperature, but at high values of neutron flux (∼1013 cm−2 sec−1) and electron density (∼1012 cm−3), the electron temperature is higher than the gas temperature by an important amount (∼600°K). Inpile measurements of electron density using microwave techniques are in very good agreement with the theoretical predictions.

Summary and conclusionsIn confirmation of our previous studies(4), it is again noted that TRIS in this in vitro system does not function as an inert buffer, and that physical-chemical interaction with insulin does occur on Whatman 3 mm paper. The degree of interaction is greater in the buffer system containing the greater concentration of TRIS. The beta-gamma globulin binding of radioinsulin in the growth-onset diabetics is not as completely dissociated by TRIS as that observed in the maturity-onset or insulin-resistant diabetic patients. This observation suggests that insulin is more tightly bound to the beta-gamma globulins appearing in the serum of growth-onset diabetics as compared to more freely dissociated binding by the beta-gamma globulins of the maturity-onset or insulin-resistant diabetic patients in this study. An alternative suggestion is that a difference in the nature of the chemical bond which is dissociated by the TRIS occurs in the sera of growth-onset diabetics. Since displacement of rad...

Single crystals have been grown based on optical quality lithium fluoride with the addition of magnesium and titanium. The content and distribution of titanium has been determined by x-ray fluorescence analysis and related to the intensity of an optical absorption band near 200 nm. The variation of thermoluminescence intensity within each crystal has been studied and related to titanium distribution.

The possible use of manganese as co-activator in the thermoluminescent system LiF: Mg has been investigated. The activators were added as fluorides during single-crystal growth by the Stockbarger-Bridgman method. Enhancement of thermoluminescence sensitivity was achieved with one sample of MnF2, but it has been shown that the agent responsible was titanium impurity in the MnF2.

Les structures electroniques des ions oxocarbonium (CH3CO)+ et [(CH3)2CHCO]+, intermediaires dans les reactions d'acylation de Friedel et Crafts, sont comparees a celle de l'acetonitrile CH3CN, apres une serie de calculs effectues suivant la methode LCAO MO SCF ab initio. La longueur de la liaison C-C a ete optimisee: les valeurs obtenues sont en accord avec l'experience. L'optimisation de la position des atomes d'hydrogene de (CH3CO)+ a conduit a la geometrie habituelle du groupement methyle. La charge positive des ions oxocarbonium est essentiellement localisee sur l'atome de carbone du groupement carbonyle. La liaison C-C de (CH3CO)+ est fortement ionique, et plus faible que dans l'acetonitrile. Dans [(CH3)2CHCO]+, ce caractere ionique est encore accentue.

An apparatus for the measurement of steady-state pre-breakdown ionization currents in helium at high pressures is described, and the sampling procedure necessary to obtain with it reproducible results discussed. The primary and secondary ionization coefficients determined from these measurements are given for 3 3 < E/p0 < 5.0 v cm-1 mmHg-1 and for 150 < p0 < 560 mmHg. The values of ? are discussed in relation to previous theoretically computed values and the experimental values obtained at lower gas pressures but with similar values of E/p0. The values of the generalized secondary ionization coefficient are found to be relatively high (similar 0.1) and to increase as E/p0 decreases.

The genus Hysterocineta Diesing, 1866, is a small genus comprised, until the present description, of only four species. Together with the genus Ptychostomum Stein, 1861, it forms the family Hysterocinetidae Diesing, 1866, which is a constituent family of the suborder Thigmotricha Chatton & Lwoff, 1949. The holotrichous ciliates belonging to this genus are characterized by the possession of elongate, flattened, flexible bodies possessing an inverted V- or U-shaped sucker at their antero-ventral margins, and a cytostome and cytopharynx at the posterior end.

Aminopterin (4-amino-pteroylglutamic acid) is not to be recommended lightly for the treatment of psoriasis, and indeed there are those who feel it should not be used at all (1). On the other hand, psoriasis may be disabling and life-ruining. There are perhaps 4 million individuals in this country who suffer with this disorder. The benefits of the drug are brought about by its toxic effect, and about one-fifth of individuals who take it according to schedules used by us do have disagreeable symptoms such as: aphthous stomatitis, gastrointestinal distress, temporary intensification of lesions, temporary partial hair loss, and temporary leukopenia. In addition, we have learned to be very cautious in using aminopterin in the following situations: universal i^- erythroderma (due to psoriasis), involvement of stasis dermatitis with psoriasis, intertriginous psoriasis, and in small, frail, aged or debilitated individuals. Last but not least, the drug must never be given during pregnancy as it is an abortifacient and might induce fetal malformations (2). Indeed there is serious question as to whether it should ever be given to a woman of childbearing age.

The conformation and the hyperfine splitting constants of the acetyl radical CH3ĊO have been studied through ab initio SCF MO calculations. The radical is found to have an eclipsed conformation with a small rotation barrier of 0.38 kcal/mole. The hyperfine splitting constants are in good agreement with experimental values. The relationship between the proton coupling constant and the dihedral angle is also investigated.

The case histories of six patients with severe salicylate intoxication are presented. The features of this disorder are discussed in the light of these case histories. The initial effect of salicylates on acid-base balance is the production of respiratory alkalosis. The basis for the respiratory alkalosis is a direct central effect which requires the anterior hypothalamus for its mediation. One of the important results of this respiratory alkalosis is hypokalemia. The hypokalemia is manifested by low serum potassium concentrations, electrocardiographic and neuromuscular changes. The persistence of hypokalemia when alkalosis is no longer present indicates that potassium depletion is likewise present. The manifestations of hypokalemia and potassium depletion may be reversed by adequate potassium therapy. Other consequences of the respiratory alkalosis may include tetany and interference with tissue oxygenation. Therapy for this phase of the disease include fluid replacement, potassium replacement, and oxygen. The use of alkali and of respiratory center depressants is contraindicated. Some patients with severe salicylate intoxication may develop metabolic acidosis following the stage of respiratory alkalosis. The manifestations of the respiratory alkalosis and metabolic acidosis are so similar that frequent blood pH measurements are necessary to guide therapy. This is particularly true because the disease may progress from one stage to the other without obvious change in the patient's status. The most important therapeutic agent for metabolic acidosis is the administration of sodium bicarbonate or lactate. Other important effects of salicylate intoxication include: fever, hypoprothrombinemia, hemorrhagic gastritis, hypermetabolism, hypouricemia, renal failure, delirium, coma, and ultimately central nervous system depression. The prognosis of the adequately treated patient would appear to be good.

Dujardin (1835) was the first to describe an adult gregarine occurring in an earthworm. This description contains illustrations of a typical Nematocystis species (Dujardin's Text-figs. B1-B7 and C1 and C2). Subsequent workers made many other observations, but it was Hesse (1909) who first carried out a comprehensive study of these parasites. It was Hesse's excellent work which laid the foundation for succeeding students of the group, the more important of whom are Cognetti de Martiis (1911, 1918, 1920, 1921, 1923, 1925, 1926, 1927), Berlin (1923, 1924), Bhatia (1924, 1924b, 1929, 1930), Bhatia & Setna (1926), Setna (1927), Bhatia & Chatterjee (1925), Troisi (1933, 1940), Tuzet & Loubatières (1946, 1948) and Loubatières (1947, 1948, 1949). Hesse gave a good historical resumé of the work carried out until 1909, while Loubatières (1949) has given a complete and very useful resumé of the work since.

This report of a survey (conducted in Fresno, California, in 1965) deals with channels chosen by adults for information about current events, their occupations, family activities, etc. The sixteen in formation channels belong to three broad classes: formal adult education, mass media, and other people. Multiple regression analyses show social and psychological predictors of channel pref erence. Percentages of use or participation are also presented within subgroups of respondents contrasted on strong predictors. It is found that each channel-especially the high-cost, high-yield channels like books and adult education-has a clearly profiled audience. Knowledge of these audience profiles will be useful to administrators of education and communication programs.

The livers from 16,776 calves 1 to 3 weeks of age slaughtered at Shepparton abattoirs were examined for gross evidence of infection with Fasciola hepatica. Those livers with thickened bile ducts were examined for the presence of liver fluke by slicing. One hundred and eight F. hepatica were collected from 84 of these livers, giving a minimum prevalence rate of prenatal infection of calves of 0.5%. These results are discussed in context with reports from other countries.

THE independent metabolic activities of some of the obligate intracellular bacteria, such as rickettsiae and chlamydiae1, have been extensively investigated2. Such work has rarely included Rickettsia rickettsi, the agent of Rocky Mountain spotted fever, because of the difficulty of obtaining sufficient material of adequate purity and stability. The only data on respiration of R. rickettsi are those given in a preliminary report by Price3, who carried out his experiments with the collection from several thousand infected yolk sacs and tested the micro-organisms immediately after the final step of purification.

An assessment of a commercial anti-human haemoglobin reagent has been conducted under experimental conditions and in forensic casework examinations. The immunoglobulin preparation used was shown to react with human haemoglobin and baboon haemoglobin in similar fashion. The sensitivity of the reagent is adequate to establish the presence of human haemoglobin in human bloodstains. The use of anti-human haemoglobin reagents in medicolegal work is advocated.

An anti-human foetal haemoglobin reagent has been assessed for the identification of foetal haemoglobin in bloodstains encountered in forensic serology. The results obtained experimentally on known material have been augmented in a ‘blind’ survey involving stains made from 38 separate cord blood samples. These results establish that this reagent when used in conjunction with anti-human haemoglobin reagent can successfully differentiate cord blood stains from those of adult blood. The methods described represent an improvement on those previously available for the identification of foetal haemoglobin in bloodstains.