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Trichloromethyl radicals (λmax < 230 nm, 230 nm = 2300 ± 450 M−1cm−1) are formed by the pulse radiolysis of aqueous carbon tetrachloride solutions. At concentrations of the order of 10−4Mand pH5.5–12.4, CCl3disappears by a second-order process with 2k = (7.4 ± 1.8) × 108 M−1s−1and without detectable hydrolysis. Both CCl3and CHCl2are believed to be formed by the pulse radiolysis of aqueous chloroform solutions but at wavelengths greater than 230 nm only absorption attributable to CCl3was observed.

Studies demonstrating paradoxical enhancement, the increase in the magnitude of a conditioned response following exposure to the conditioned stimulus alone, are reviewed. Theories currently used in explaining the phenomenon are discussed. Increased understanding of the parameters involved in the traditional extinction situation have implications for research into the ontogeny of human anxiety syndromes and for differential therapeutic prescriptions in a behavior modification setting.

A fully dynamic, self-consistent computer code has been developed to solve internal electromagnetic pulse (IEMP) problems in cylindrical geometries excited by a pulse of ionizing radiation. Comparisons between the fully dynamic and previous quasi-static solutions are made, and the range of validity of the quasi-static approximation is defined. Results show that non-linear effects arising from field-perturbed electron motion significantly affect the range of validity of the quasi-static approximation.

A study is reported of the influences exerted on the levels of the circulating eosinophils, lymphocytes and neutrophils of rats in which body temperatures have been elevated for one hour to 41.0 or to 41.5 C. by means of the Raytheon microwave diathermy apparatus. Preliminary studies were made to determine the influence exerted on these blood categories by the restrictions imposed on the animals such as confinement in cages and insertion of rectal thermistors: factors incident to the experimental procedure. Data were assembled on intact animals, trained to cage confinement and to thermistor implacement, and on such animals subjected to the elevated temperatures. Data were also assembled on adrenalectomized animals, hypophysectomized animals, hypophysectomized-adrenalectomized animals and adrenal-demedullated animals. These data warrant the following conclusions: 1. Cage restrictions and the insertion of the thermistor into the rectum resulted in a mild form of stress inducing a slight eosinopenia, a lymphopenia and a mild neutrophilia. The energy of the microwaves, applied for one hour, greatly accentuated those changes, resulting in marked eosinopenia and lymphopenia, with a greatly increased neutrophilia. When temperatures ranging from 41.0 to 41.5 C. were induced for one hour in previously trained rats, the total eosinophil tabulation decreased in four hours from a control level of 171 ± 24 cells per cu. mm. of blood to 41 ± 5 cells, a decline of 76 per cent. The total number of mononuclear leukocytes decreased from a control level of 19,940 ± 1,000 cells to 8,330 ± 810 cells immediately after heating, while the total number of neutrophilic leukocytes increased from a control level of 3,580 ± 650 cells per cu. mm. to 8,770 ± 1,920 cells at two hours after heating. 2. Adrenalectomy altered the hemograms of rats subjected to those elevated temperatures, by abolishing the eosinopenic and the lymphopenic trends but it did not alter the neutrophilia. 3. Removal of the pituitary gland from animals prior to the increases in their temperatures resulted in an average decrease in the number of eosinophils, a decrease which was not considered significant. The number of neutrophilic leukocytes remained high. 4. When animals lacking both pituitary gland amid adrenal glands were subjected to the same energy for one hour no significant alterations in the number of eosinophils, of lymphocytes or of neutrophils were recorded. 5. The adrenal medulla did not appear to play a significant role in the chain of events leading to the characteristic hemogram in animals subjected to fever. In adrenal-demedullated animals an eosinopenia, a lymphopenia and a neutrophilia occurred as in normal intact animals. 6. The conclusion seems warranted that hyperpyrexia has produced pituitary and adrenocortical stimulation.

A series of experiments was conducted with 5-day-old White Leghorn (Hy-Line) cockerels. Six-mercaptopurine and a palladium complex of this compound were administered orally to 5-day-old chicks at equal dosage levels on a milligram basis for 10 days. At equal dosage levels, the leukopenia induction capacity of the two compounds was essentially the same at the end of the 10-day treatment period. The palladium complex was less toxic, as demonstrated by greater weight gain and lower mortality. At equimolar dosage levels, results were similar to those observed when evaluation of equal dosage levels was conducted.

The dislocation content of walls formed by fatigue was studied using an optical bench. The experiment showed that the optical bench can be used to help analyse the dislocations in dense arrays; in particular, considerable information can be obtained from Fraunhofer diffraction patterns of the micrographs.

D-α-Fructoheptonic lactone (I) was oxidized with an equimolar amount of periodic acid to give formaldehyde and a hexuronic lactone (II) which was hydrolyzed to crystalline 4-C-hydroxymethyl-L-xyluronic acid (III), (68% yield). Hydrogenation of III gave an aldonic acid which was isolated as crystalline 2-C-hydroxymethyl-L-xylonic lactone (V). Reduction of V by sodium amalgam gave 2-C-hydroxymethyl-D-xylose (VI), which crystallized after purification as the 2,5-dichlorophenylhydrazone. Hydrogenation of VI gave 1,1-di(C-hydroxymethyl)-D-threitol (VII) which was purified as the crystalline hexaacetate. Treatment of III with methanolic hydrogen chloride gave a glassy material which was reduced by sodium borohydride and hydrolyzed by hydrochloric acid to give 4,4-di(C-hydroxymethyl)-D-threose (IX), which was isolated and characterized as the crystalline 2,5-dichlorophenylhydrazone. Oxidation of III by either bromine or nitric acid gave 2-C-hydroxymethyl-D-xylaric acid (IV), which was characterized as the crystalline ammonium salt.

Bromal labelled with C14in the carbonyl group has been used to show that small amounts of carbon dioxide and carboxylic acids are produced in the radiolysis of aqueous bromal solutions. Gvalues for the production of CO2and carboxylic acid are about 7.5% and 15% of those for HBr production, respectively. The observed yield of carboxylic acid is in agreement with that found by titration.

Eleven patients with pulmonary tuberculosis were treated with high dosages of “Gatalone” (usually 1600 mgms. daily) for a period of six months or longer.

Nuclear magnetic resonance measurements upon polymerizing methyl methacrylate solutions show that a significant proportion of the solute molecules (naphthalene, phenanthrene) remain untrapped when the material becomes solid (60–30% residual unsaturation), complete rigid trapping of the solute occurring only as the unsaturation present is reduced to near zero.Phosphorescence measurements show increasing phosphorescence from solid polymethylmethacrylate containing phenanthrene as the residual unsaturation in the polymer is reduced from about 4% to zero, which is attributed to the gradual immobilization of an increasing fraction of the solute molecules as the unsaturation is reduced. Methyl isobutyrate reduces the phosphorescence from solutions of phenanthrene in polymethylmethacrylate at room temperature, but polymer solutions containing methyl isobutyrate and those containing residual unsaturation phosphoresce strongly at 77 °K.

Mixtures of ethyl iodide with chloroform, carbon tetrachloride, and dichloromethane have been irradiated with 60Co γ-radiation. Reduced yields of iodine, hydrogen iodide, and hydrogen chloride from ethyl iodide – chloroform and ethyl iodide – dichloromethane mixtures and of chlorinated ethanes from ethyl iodide – chloroform are attributed to radical scavenging by iodine and dissociative electron capture by the chlorinated methane.Electron capture by carbon tetrachloride followed by ion–molecule reactions between ethyl iodide cations and ethyl iodide, or neutralization of these cations by chlorine anions, explains iodine yields observed at low ethyl iodide concentrations in carbon tetrachloride greater than those expected on the basis of partition of absorbed energy. In this mixture, neutralization of an ethyl iodide cation by a chlorine anion gives rise to an enhanced hydrogen chloride yield.

Crystalline D-α-fructoheptose (2-C-hydroxymethyl-D-glucose) has been obtained by the sodium amalgam reduction of D-α-fructoheptonic lactone. Some crystalline derivatives of the sugar are described and also the crystalline heptacetate of D-fructoheptitol (1,1-C-di(hydroxymethyl)-D-arabitol).

Aqueous bromal hydrate solutions have been irradiated with Co60gamma rays and the production of acid measured. The effect of bromal hydrate concentration, dose rate, pH, and temperature upon the yield of acid has been determined. Major products of the radiolysis have been identified and are compared with those formed when aqueous bromal hydrate solutions are treated with Fenton's reagent, a mixture of hydrogen peroxide and ferrous sulphate solutions. It has been shown that Fenton's reagent will initiate a chain reaction in aqueous bromal hydrate solutions which produces hydrobromic acid.

Dilute aqueous solutions of some halogen-substituted ethanols, acetaldehydes, and acetates have been irradiated with Co60gamma rays, and the yield of acid products determined. Irradiations were carried out using air-saturated solutions and also solutions from which the air had been displaced by nitrogen or hydrogen. The acid yields are correlated with the structure of the organic compounds.

Hydrogen bromide, glycolic acid, and carbon dioxide have been identified as products of the γ-radiolysis of aqueous 2,2,2-tribromoethanol solutions. The effect of oxygen, tribromoethanol concentration, and dose rate upon the yields of bromide ion and acid have been determined, and partial radiolysis mechanisms are proposed for reaction in the presence and absence of oxygen. Dibromoacetaldehyde, reported to be a product of the photochemical decomposition of tribromoethanol solutions, was not detected in the radiolysis experiments or in tribromoethanol solutions exposed to sunlight.

Saturated aqueous chloroform solutions (0.07 M) with pHranging from 0.8 to 12.6 have been irradiated with 60Co γ-radiation in the presence and absence of air. G(Cl− + ClO−) increases with increasing pHin the pHrange 1–3 (aerated solutions) or 3–6 (deaerated solutions) and again at pHgreater than 10.5. The variation in yield from aerated solutions in the region pH1–3 is attributed to competition between chloroform and hydrogen ions for hydrated electrons. However, such competition cannot account for the pHeffect observed in deaerated solutions between pH3 and 6. Increased yields from both aerated and deaerated solutions at high pHare attributed to the formation of O−by reaction of hydroxyl radicals and hydroxide ions. Formic acid and oxalic acid have been identified as minor products when aerated chloroform solutions are irradiated.

The surface structures and interior dislocation structures of fatigued copper and copper-5 at. % aluminium crystals have been studied using replicas and scanning and transmission electron microscopy techniques. A very regular structure of walls of dislocations has been found; these walls consist of primary edge dipoles held together by a mesh of secondary dislocations. It is suggested that the wall structure is the 'ideal structure' to which other structures tend as the fatigue process progresses, and that this regular structure is found in the persistent slip bands.

Measurable ions are formed when organic compounds are oxidized on the surface of a heated platinum filament in the presence of oxygen. Certain types of compounds yield ion currents on the same order of magnitude as those found in the FID. In contrast to the hydrogen flame detector the molecular structure of the compound oxidized has a profound effect upon the ion current obtained. Of hydrocarbons studied, those containing the neopentyl grouping such as 2,2-dimethylpropane and 2,2-dimethylbutane produced the highest ion yields, about one coulomb or more per mole. Branched hydrocarbons containing methyl groups attached to different atoms of the carbon chain yielded about one tenth the ions obtained from the neopentyl series and normal hydrocarbons, one twentieth or less. Alcohols, aldehydes, ketones, and esters have also been investigated and were found to yield ions. Alcohols have been studied in some detail, and again, the structure of the molecule strongly influenced the extent of ionization. Methanol and ethanol produced essentially no ions while 2,2-dimethylpropanol yielded more than six times the ion current produced by an equal amount in the FID. The response of the detector has been shown to be linear to quantities of hydrocarbons up to at least several micrograms. The utility of the catalytic ionization phenomenon as a gas chromatographic detector has been investigated.

Total picker losses (gleaned ear corn and shelled corn) averaged 6.0, 6.9, 10.3, and 13.4% of the total yield for average populations of 10,300, 14,900, 18,900, and 22,900 plants per acre, respectively at 6 locations in Michigan. Within the recommended plant populations for Michigan (up to 16,000 plants per acre) there were no significant increases in either ear or shelled corn losses as population was increased. Stalk lodging increased and ear size decreased as the population increased but neither was a serious handicap to mechanical harvest. The percent of husk‐free ears after picking was not affected by plant population.

Rats must learn to swim down a tank of water, and motivation (drive stimulus intensity) is manipulated by means of the water temperature. Reinforcement (reduction in drive stimulus intensity) is manipulated independently by means of the differential temperature between the alley tank and a separate goal tank. The purpose of this note is to generally describe the technique and indicate its usefulness for the study of instrumental escape conditioning.

An alley and goal tank are connected to separate reservoirs containing constant temperature circulating units. These units allow automatic and precise control of water temperature which is used to manipulate drive and reinforcement with small laboratory animals.

In order to ascertain whether training conditions are complicated by adaptation effects in a water-escape situation rats (N= 96) were exposed for 10 or 100 sec. to 15° or 32° C prior to each escape trial from a 15° C tank. Compared to a non-exposed control condition over-all performance of the 15° C exposed groups was unaffected, but the performance of the 32° C exposed groups was significantly (p< .0005) enhanced. Adaptation effects which would lower the effective drive intensity in the escape situation, then, were not present, but prior exposure to a warmer condition did serve to increase the effective drive level. The absence of adaptation effects is related to similar findings with electric shock.

A series of experiments was conducted with Black Minorcas and partially inbred White Leghorn chicks of 1, 12, 14, and 16 days of age. Six-mercaptopurine and a platinum complex of this compound were administered orally to chicks of various ages at 612 mg/kg/day, 306 mg/kg/day, and equimolar dosage levels for various treatment periods. At equal dosage levels the capacity of the two compounds to induce leukopenia in the chick was essentially the same, however, the platinum complex was less toxic, as evidenced by greater weight gain, lower mortality, and LD50determinations. When the 6-MP complex was compared with 6-MP at twice the dosage level of the latter, and at equimolar dosage levels, results were similar to those obtained when equal dosage levels of the two compounds were evaluated.

Evidence is presented to show that the hydrated electron reacts with monohydrogen sulfide ion with a rate constant of (3.0 ± 0.4) × 107 M−1s−1in contrast to an earlier report that this substrate was unreactive. A comparison of the electron reactivity towards hydrogen sulfides and selenides suggests that the reactivity reflects the ability of the substrate to accommodate the electron as opposed to its ability to donate a proton to the electron.

ONE of the most satisfactory features of recent advances in the X-ray analysis of compounds of high molecular weight has been the degree of co-ordination between the efforts of the structure analyst and those of the chemist. Especially is this true in the case of investigations of the structure of cellulose and its derivatives. The question of protein structure, however, appears to bring in its train problems of quite another order of complexity, and it does not seem to be at all clear what is connoted by the phrase ‘molecular weights of proteins’. Such X-ray photographs of fibrous proteins as have been obtained point to the periodic repetition of comparatively simple units with imperfect or variable side-linkages. In the quest for chemical data to correlate with these results, the crystallographer is at once brought up against the remarkable observations of Svedberg, that there are groups of soluble proteins of ‘molecular weights’ which are simple multiples of 34,500. The present situation is most simply described by quotations from two recent letters 1, 2to NATURE :-

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