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The postulate that single roots of Zea mays transport their absorbed phosphorus nonuniformly to the leaves was tested. Plants were grown under growth chamber conditions for three to four weeks in nutrient solution. At this stage of growth a series of plants was placed into a system in which two roots on each plant were allowed to absorb either 33P or 32P from uptake solutions for time intervals of up to 24 hours. Plants subsequently were harvested such that each leaf was partitioned into samples containing tissue from one side or the other of the midrib. All samples were assayed for 33P and 32P and the results were expressed as the amount of total P transported into different plant parts from a single root. Nonuniform P accumulation in the leaves occurred and different patterns of accumulation, dependent on the type of root chosen for uptake were observed. Nearly uniform P accumulation occurred between one side and the other of a given leaf when transport was from radicle roots. In marked contrast, transport from adventitious roots resulted in an alternating pattern of accumulation between one side and the other of each successive leaf up the stem. The seminal root system supplied more P to the older leaves than did the adventitious root system. The nature of these nonuniform P transport patterns is attributed to the vascular organization between roots and leaves. [ABSTRACT FROM AUTHOR]

A boron requirement has been shown for 12 species of marine pinnate diatoms, 4 species of marine centric diatoms, and 8 freshwater diatom species. It can be concluded that boron is essential for the growth of most, probably all, diatoms. It is much easier to demonstrate a requirement for the marine species than for the freshwater species. Some species of marine algal flagellates also require boron for growth; other apparently do not. [ABSTRACT FROM AUTHOR]

The distribution of aluminium, nitrogen, calcium and phosphorus in the cortex cells of bean and barley roots was investigated by means of X-ray microanalysis. Aluminium was apparently localized inside the cell-lumens and its distribution overlapped that of nitrogen. More calcium was observed in the cell walls. No correlation between the distribution of aluminium and phosphorus was found. [ABSTRACT FROM AUTHOR]

The variation in Skeletonema cells grown at 3 klux continuous illumination and 20°C is reported. Four different types of lamps gave no difference in the photosynthetic characteristics. The average diameter of the cells decreased from 8-3.5 μ during their six months vegetative period. The ratio between the pigment content in the largest and the smallest cells was about 2:1. A good correlation between cell volume and chlorophyll a content was found for this species. The content of chlorophyll c generally varied between 4 and 17 per cent of the chlorophyll a content -- A distinct correlation between the chlorophyll a content and the rate of photosynthesis per unit of cells at low light intensity was found. The rate of photosynthesis, in mg C per mg chlorophyll a and hour at 1 klux, varied between 0.40 and 0.70 for all 60 experiments with an average value of 0.56. The corresponding value for cells deficient in phosphorus was 0.19 and for cells deficient in nitrogen 0.09. -- The material also showed a good correlation between the rate of photosynthesis per cell at 1 klux and the light-saturated rate of photosynthesis. Ik varied between 7 and 13 klux. [ABSTRACT FROM AUTHOR]

This paper describes an investigation into the electrical behaviour of shallow implantations of boron and phosphorus in silicon. The clover-leaf Van der Pauw patterns were defined by planar masking techniques, and were ion implanted to produce a 'tailored' impurity profile of approximately uniform concentration with depth.
It was found that phosphorus implantations became fully electrically active after annealing at a temperature between 620degreesc and 750degreesc, whereas the boron implantations required an anneal in excess of 900degreesc. A subsidiary activity peak, whose magnitude increased with the ion dose, was observed for the boron implantations after annealing at a temperature around 520degreesc.
The principles of ion implantation have been discussed at length by other authors, for example Gibbons (1968), Kleinfelder (1967) and Nielsen (1967), and recently Large (1969) has described the techniques used at S.E.R.L. During the past two years, papers have been published showing the electrical properties of silicon implanted with various ion species, but very little information has appeared on the electrical behaviour of shallow implantations of boron and phosphorus. The present work was initiated to measure these properties in order that the electrical behaviour of ion-implanted silicon devices be more fully understood. [ABSTRACT FROM AUTHOR]

Focuses on an experiment on the uptake of boron by some clays from artificial sea-water solutions at room temperature. Procedure of uptake process of boron; Factors that promote boron adsorption by clays; Effect of properties of clay-mineral polymorphs on boron concentrations.

The article investigates the incidence, nature and characteristics of children with anoxic damage and the clinically normal counterparts. Children with a history of oxygen deprivation frequently evidence concern about personal imbalance and about precariously supported objects. The study reveals that anoxic-damaged children more frequently than normal counterparts manifest sensitivity to imbalance, forecast the disintegration of a house and interchange the legs of the Manikin. The imbalance is ascribed more frequently to human rather than physical causes and is believed to be more apt to portend human discomfort than material disequilibrium.