William Armstrong

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The hydrochloride salt of a new, small molecular weight (M.W. = 286) biotin-containing compound referred to as biotinamide (N-(2-aminoethyl)biotinamide) was compared with biocytin (M.W. = 372) for its use in intracellular labeling of neurons and in neuronal tracing experiments using avidin conjugates for histochemical detection. The DC resistance and(More)
Young Phragmites plants were grown in two cocktails of monocarboxylic acids (C(1)-C(5)) at pH 6, where the concentration of each acid was innocuous and the total undissociated (potentially toxic) concentrations were 0.35 mmol/L and 0.42 mmol/L. Rice plants were subjected to 1.5 mmol/L acetic acid at pH 4.5 (undissociated concentration = 1.05 mmol/L). In(More)
BACKGROUND AND AIMS Akagare and Akiochi are diseases of rice associated with sulfide toxicity. This study investigates the possibility that rice reacts to sulfide by producing impermeable barriers in roots. METHODS Root systems of rice, Oryza sativa cv. Norin 36, were subjected to short-term exposure to 0.174 mm sulfide (5.6 ppm) in stagnant solution.(More)
The topographic organization of the facial nucleus motoneurons in the rat was investigated with the horseradish peroxidase retrograde tracing method using tetramethyl benzidine as a chromogen. Facial muscles were 'represented' on the facial nucleus in an orderly fashion. For example, the motoneurons supplying the rostral (nasolabial) muscles are laterally(More)
The subapical regions of wetland plant roots can develop a barrier to radial O2 loss (ROL), but barrier resistance has rarely been quantified in terms of its O2 diffusivity. Barrier resistance in adventitious roots of the waterlogging-tolerant Hordeum marinum was assessed from measurements of ROL using cylindrical platinum electrodes while either varying(More)
AIMS Soil waterlogging impedes gas exchange with the atmosphere, resulting in low P(O2) and often high P(CO2). Conditions conducive to development of high P(CO2) (5-70 kPa) during soil waterlogging and flooding are discussed. The scant information on responses of roots to high P(CO2) in terms of growth and metabolism is reviewed. SCOPE P(CO2) at 15-70 kPa(More)
Few studies have examined exodermal development in relation to the formation of barriers to both radial oxygen loss (ROL) and solute penetration along growing roots. Here, we report on the structural development, chemical composition and functional properties of the exodermis in two diverse wetland grasses, Glyceria maxima and Phragmites australis.(More)