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Humic acid, a soil humic material that occurs widely in soils and waters, can firmly retain or complex certain chlorinated phenoxyacetic and benzoic acids which are widely used as herbicide. The extent of retention depends on the nature of the compound. The latter appeared to be complexed by a mechanism that most likely involves adsorption on large surfaces provided by humic acid in addition to more firmer retention in internal spaces of its structure. The complexing behaviour of humic substances for herbicides should be of interest to those concerned with environmental problems. [ABSTRACT FROM PUBLISHER]

A young woman aged 17 developed abdominal and psychiatric symptoms followed by jaundice and photosensitivity during the first trimester of her first pregnancy. She was found to have hereditary coproporphyria and eventually gave birth to a stillborn infant. She continued to excrete excessive amounts of coproporphyrin throughout her uneventful second pregnancy and, during the puerperium, developed epileptiform attacks and severe hypertension for the first time. A family study revealed 3 members with latent hereditary coproporphyria. The symptomatology in this case is compared with others reported. [ABSTRACT FROM AUTHOR]

Experience with tetracosactrin-depot therapy in 10 patients with dermatological disorders is described. The clinical response was considered good in 7 patients, poor in the remaining 3. Plasma cortisol levels remained elevated 24 to 48 hr, following injection but there were considerable differences between patients in both the magnitude and duration of response. Melanoderma and other side effects were troublesome when the total weekly dose exceeded 1 mg. Smaller dosages gave satisfactory response without significant accompanying side effects. [ABSTRACT FROM AUTHOR]

Soil columns were used to study sulphate distribution in Thin Duagh Loam soil as influenced by the presence of a water table. The concentration pattern showed that retention was greater in the surface soil than at lower depths. The data suggest that sulphate tends to move more slowly than water in soil. [ABSTRACT FROM AUTHOR]

A method is described for determining the true equilibrium soil solution for a saline soil adjusted to various moisture contents by interpolation of ion ratios in solution before and after equilibration. Over the moisture range studied, equilibrium values were different at each moisture content. The ionic strengths of the equilibrium solutions were considered to be too high for calculation of activity coefficient and therefore concentration ratios were used instead of activity ratios. The ionic strength and ion ratios for the soil equilibrium solutions changed gradually over the moisture range 35 to 100 per cent, but abruptly over the lower moisture range (5 to 35 per cent). The expression log(Na)-½ log(Ca) is regarded as being particularly important. [ABSTRACT FROM AUTHOR]