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Light affects the mobilization and distribution of several of the storage components of the cotyledons of germinating soybean seeds. The nitrogen content of the cotyledons began to decrease during the first day of germination, continued through day 12 for plants in the light, and day 14 for those in the dark. Cotyledons from both treatments had lost about the same amount of nitrogen by day 14. Plants from both treatments lost about the same amount of dry weight by day 8, but those in the light had taken up nitrogen from the nutrient solution; while those in the dark showed no increase. The plants in the light had higher concentrations of soluble amino nitrogen in the cotyledons than did those in the dark, but the opposite was true for the seedling axis. Aspartate and its amide accounted for half or more of the total free amino acids in all parts of dark‐grown plants at 6 and 14 days. In the light‐grown plants aspartate and asparagine usually accounted for less than half of the total free amino acids in all plant parts except the cotyledons at 6 and 14 days. Total soluble amino acids were much lower in these plants than those in the dark, excepting the cotyledons.

An investigation was conducted to determine the effect of frequency and amplitude of axial vibration and of bearing axial play in producing fretting damage in unlubricated ball bearings at constant temperature and humidity. A study was also made of the impact forces occurring within the bearings due to these vibrations. A simplified analog simulation model of the ball bearing and the vibration exciter system was also developed.Frequency, amplitude, time, and a derived parameter GxI (the product of acceleration and impact frequency) had a very significant influence on fretting damage, indicated statistically at a confidence level of ninety-nine percent. Although axial play had little effect on fretting damage for the range of axial plays of the test bearings, it had significant effect on the acceleration levels obtained within the bearings. Fretting damage was measured with a bearing torque analyzer. The experimental test vibrations were accurately reproduced on the analog model.

Previous studies have shown that ozone in low concentration in vivo depresses the activity of alveolar macrophage acid phosphatase, lysozyme, and β-glucuronidase. In the present studies, rabbit alveolar macrophages were held in tissue culture as a monolayer and were exposed to various concentrations of ozone when covered by only a film of tissue culture media. This approach eliminated recovery of a mixed population of cells from the lung and possible influx of macrophages in response to the noxious agent. Ozone in moderately low concentration, 2 ppm, depressed the activity of macrophage lysosomal acid hydrolases. There was slight accumulation of enzyme in extracellular media during and after three hour exposure to ozone. Hydrolase depression effect was eliminated when the culture media contained sulfhydryl donating reagents—glutathione and cysteine. This may offer a clue to a mechanism of ozone toxicity.

All flints containing unstable impurities are susceptible to patination. The rate of patination varies with many factors: (i) the texture and microstructure of the flint; (ii) its permeability; (iii) the kind, proportion, and distribution of impurities; and (iv) environmental factors, such as temperature and soil chemistry. The thickness of the patina varies also with time.Two contrasting types of patina can develop: a chalky white patina and a ferruginous brown patina. Both types are observable primarily as a color change, and study of these types is facilitated by a clear understanding of the causes of color in flint.The color of most flints is the result of repeated refraction and reflection of light at numerous intergranular surfaces, whereby part of the light is internally absorbed and part is reflected back to the observer. The ratio of reflected to absorbed light governs the lightness of the color, or its value. The preferential absorption of certain wavelengths by natural pigments (such as iron oxide and hydrous iron oxide) disseminated through the flint determine the hue of the color.The color changes produced during patination relate to changes in texture and impurity content occasioned by the attack of weathering agents on impurities in the flint. The creation of voids by the dissolution and leaching of carbonates, the loosening of quartz crystallites, and the dispersal of clays all modify the reflectivity of the flint. Chemical changes involving the pigments, their dispersal along intergranular surfaces, or removal by leaching modify both reflectivity and capacity to preferentially absorb.Attempts to correlate patina thickness with age, and thus to use flint patinae chronometrically, have proven unsatisfactory because other factors, whose importance in some cases exceeds that of age, have not been taken into account. The texture and microstructure of flint, its permeability, and the kind, proportion, and distribution of impurities can be evaluated by regular petrographic techniques. Environmental factors can be assumed constant for artifacts from the same types of soil in a given climatic region. Only after allowances have been made for these additional variables does the age-dependence of flint patination become clear.

An experimental investigation was undertaken in which dropwise condensation was caused to occur on the upper side of a 0.001-in-thick horizontal copper condensing surface. The lower side of the condensing wall was convectively cooled, and the cooled-side temperatures under growing droplets were measured using infrared-radiation techniques. Temperature measurements showed good agreement with the results of a finite-element analysis of the droplet and condensing surface. Both experimental and analytical results pointed to the existence of an area of very high heat transfer right around the droplet perimeter, and to the importance of the condensing wall as a heat-diffusing mechanism in dropwise condensation.

The compound (GeF2)3 GeF4 has only recently been characterized1. A number of the physical and chemical properties of (GeF2)3 GeF4 are now known, including among others, its thermal behaviour and enthalpy of formation. The Raman spectrum and broadline NMR spectrum have not been presented and in this report they are described for the first time.

The ultra-violet absorption spectrum of uranium hexafluoride has been well documented(1), and some vibrational structure has been reported. The purpose of this work was to determine whether any rotational fine structure was present using conventional high resolution spectrographs. The absorption spectrum of gaseous uranium hexachloride is difficult to study because of the low vapour pressure of the compound and its thermal instability. Previous workers(2) did not publish a spectrum.

The cyanogenic secretion of the polydesmoid millipede Apheloria corrugata(Wood) is discharged from paired, serially arranged glands, each consisting of two compartments. In one compartment is stored an undissociated cyanogenic compound, and in the other, a chemical factor that triggers cyanogenesis. The gland is constructed in such a way that the contents of the two compartments are mixed, and cyanogenesis is initiated, at the very instant of discharge. The stored cyanide precursor may be mandelonitrile.

The characteristic ability of rat uteri to take up tritiated estradiol in vitro or to retain estradiol previously incorporated either in vivo or in vitro is destroyed by treating the tissue with various sulfhydryl-blocking reagents. The two radioactive estradiol-receptor complexes, observed in uterine homogenates in the supernatant fraction and in an extract of the nuclear fraction, respectively, are disrupted by brief exposure to organic mercurials in the cold. Sulfhydryl groups of uterine receptor substances apparently play a vital role in estradiol binding, perhaps indirectly through contribution to receptor conformation.

An aldehyde, trans-2-dodecenal, heretofore known only from plants, has been identified in the defensive secretion of the spiroboloid millipede Rhinocricus insulatus. A second component, 2-methyl-1,4-quinone, was previously known from the secretion of related millipedes.

A LARGE number of bands have been assigned1to the molecule tellurium monoxide (TeO); but little agreement has yet been reached on their vibrational analysis, and no rotational analysis has yet been reported. By analogy with SeO (ref. 2), it is to be expected that the visible and near ultra-violet bands arise from a transition 3∑−– 3∑−in which the spin-splitting constants λ′ and λ″ are large. In the limit of case-c, the predicted 3∑−– 3∑−system will appear as two separate systems, 1 – 1 and 0+– 0+. Some preliminary observations of the absorption spectrum taken in a second order of a 6.65-m concave grating spectrograph support this view.

In previous papers of this series, we reported the identification of active principles in the defensive secretions of several spiroboloid, polydesmoid, and chordeumoid millipedes (H. E. Eisner et al. 1963, T. Eisner et al. 1963a, 1963b, Monro et al. 1962, Wheeler et al. 1964). This note deals with the secretions of 6 species belonging to yet another order, the Spirostreptida: Family: Cambalidae Cambala hubrichti Hoffman (Highlands, N. C.) Family: Spirostreptidae Orthoporus flavior Chamberlin and Mulaik (Dryden, Texas)

The defensive secretion of the tenebrionid beetle Eleodes longicollis LeConte contains—in addition to three quinones previously identified—the hydrocarbons 1-tridecene and 1-undecene, and glucose. 1-Nonene may also be present.