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Breeding bird populations were studied on seven riparian woodland study plots in north-central Arizona. The densities of breeding birds varied from 193 to 847 pairs per 40 hectares. These differences were, in part, related to the vegetative structure of the habitat. Bird species diversity (BSD) was not correlated with foliage height diversity (FHD) in riparian habitats consisting of one major vegetational component (the cottonwood tree ) where these habitats are bordered by agricultural fields. These areas supported the largest breeding bird populations (847, 612, 512, and 425 pairs per 40 hectares) while areas consisting of a mixed deciduous tree and shrub component () had smaller populations of breeding birds (322, 312, and 193 pairs per 40 hectares). On the mixed deciduous woodland areas the correlation between BSD and FHD was similar to what others have found in Eastern deciduous forests. The average weights of individual birds were significantly greater on the homogeneous cottonwood areas ( = 46.4 g) than on the mixed deciduous areas (= 22.9 g). Data gathered indicate that two systems of social organization are being maintained. In areas of relatively low population density (mixed deciduous) 57% of the pairs maintained “class A” territories. On areas of relatively high population density (homogeneous cottonwood) only 22% of the pairs exhibited this form of spacing; here, most birds forage freely outside of the riparian habitat. We suggest that the differences in population density and average weights of birds found in the two habitat types are a result of the following: (i) relative productivity of areas adjacent to the riparian habitat, and (ii) degree of intra- and interspecific competition effected by avian populations found breeding in areas adjacent to the riparian habitat. [ABSTRACT FROM PUBLISHER]

A 27-year-old male patient fasted under supervision for 382 days and has subsequently maintained his normal weight. Blood glucose concentrations around 30 mg/100 ml were recorded consistently during the last 8 months, although the patient was ambulant and attending as an out-patient. Responses to glucose and tolbutamide tolerance tests remained normal. The hyperglycaemic response to glucagon was reduced and latterly absent, but promptly returned to normal during carbohydrate refeeding. After an initial decrease was corrected, plasma potassium levels remained normal without supplementation. A temporary period of hypercalcaemia occurred towards the end of the fast. Decreased plasma magnesium concentrations were a consistent feature from the first month onwards. After 100 days of fasting there was a marked and persistent increase in the excretion of urinary cations and inorganic phosphate, which until then had been minimal. These increases may be due to dissolution of excessive soft tissue and skeletal mass. Prolonged fasting in this patient had no ill-effects. [ABSTRACT FROM PUBLISHER]

This article examines the effect of new television stations on the Canadian Broadcasting Corporation's (CBC) share of audience. This paper has shown that if it was hypothesized that a group of faithful viewers as defined, and make certain plausible assumptions about their behavior, a formula can be constructed that yields some interesting predictions. It has not demonstrated that such an audience does, in fact exist, or who the people are that make it up, or why. A 1962 CBC study did give a note on certain identifying characteristics of those who prefer CBC-owned and non-CBC-owned television stations, without, however, linking these people and their viewing habits. In general, the study showed that those who preferred CBC stations tended to have a longer period of formal education than those who preferred non-CBC stations; they tended to include a higher proportion of senior people in the white-collar class; and they tended to be rather older. As for program tastes, those who preferred CBC to non-CBC stations were distinctly less critical of CBC programs for being too heavy and serious; they felt that their station did a good job in drama and they had a higher regard for current events discussions than those who preferred independent or U.S. stations.