Showing papers by "University of Zambia published in 1970"

The accumulation and binding of copper in leaf tissue of becium homblei (de wild.) duvign. & plancke

Abstract: Summary The flowering plant Beciutn homblei is able to accumulate copper and other heavy metals to a relatively high level in its leaves. Approximately 17% of the total copper is concentrated in cell walls where it is bound as an organic complex. Copper in water extracts of leaf tissue is not in free ionic form but is complexed with amino acids or peptides. In vitro experiments indicate the strong complexing powers with copper of certain substances in leaf tissue.

Effect of Cultural Value of Time upon Recall

Abstract: Two groups of subjects were asked to recall a set of numbers which were presented to them in the context of a short story. Some of the numbers pertained to temporal phenomena, whilst others related to other non-temporal events in the story. It was found that while there was a non-significant difference between rural women and urban schoolboys in recall of numbers (other than price) not relating to temporal phenomena, a significant difference did occur in the case of the temporal phenomena, the rural women being inferior. It is argued that this experiment shows more clearly than time estimate experiments the effect of differing cultural values of time.

The distribution of carboxylic esterases in the area postrema of the guinea pig.

Abstract: Detailed studies were made on the distribution of carboxylic esterases in the area postrema (AP) of the guinea pig In this species the nerve cells of the AP show intense acetylcholinesterase activity which greatly enhances a morphological study of these elements The two main types of nerve cells arebipolar cells andmultipolar cells The bipolar cells often send their peripheral processes to the wall of a capillary, while the other processes go towards the nervous tissues outside of the organ A similar behavior of the processes could be observed in the case of the multipolar cells A special multipolar cell having bulb-like endings in the neuropilema of the organ has been discussed On the basis of these findings it is conjectured that these neural elements, as well as the AChE positive nerve fibers located along the walls of the capillaries, function as parts of a chemoreceptor system, the existence of which has been postulated by former authors The non-specific esterase activity of the organ is rather diffuse B esterases have been described in the glial cells and in several nerve cells and in the pericytes and endothelial cells of the perivascular space The localization of A and C esterases appeared diffuse, but only the AP showed intense C esterase activity in the caudal medullary area

The music of Zumaile village, Zambia

Abstract: Zumaile village lies south of Minga Mission in the District of Petauke, Eastern Province of Zambia, within three miles of the Mozambique border. The village people belong to the Nsenga tribe. In 1923 a Roman Catholic Mission was established at Minga, some 20 miles north, and in the following year its evangelizing activities spread to Zumaile where, at the time this survey was made in September 1968, most of the villagers had been converted to Roman Catholicism. Some generations ago Zumaile (according to local tradition) had arrived from the Nsenga tribe in Mozambique and settled on this spot. Many of the musical traditions of the village had become obsolete and new ones had replaced them. What follows is a brief description of these traditions.

Synthesis and some reactions of 1‐(4.6‐dimethoxybenzo‐furanyl)‐ and 1‐(4.6.7‐trimethoxybenzofuranyl)butane‐1.2.3‐trione‐2‐arylhydrazones

Abstract: Both 4.6-dimethoxy-(1c) and 4.6.7-trimethoxy-5-acetoacetylbenzofuran 1d are obtained from visnaginone (1a) and khellinone methyl ethers 1b, respectively, by a CLAISEN condensation. The β-diketones 1c and 1d couple with aromatic diazonium compounds to form the hydrazones 2a – i. 1-(4.6-Dimethoxybenzofuranyl)- and 1-(4.6.7-trimethoxybenzofuranyl)butane-1.2.3-trione-2-arylhydrazones 2 a–i react with hydrazine hydrate in acetic acid to yield the corresponding pyrazole derivatives 3a–i or 4a–i. The monohydrazones 5a–b are isolated when 2e or 2i are treated with hydrazine hydrate in ethanol. The hydrazones are converted to the respective pyrazoles by the action of glacial acetic acid. Hydroxylamine hydrochloride reacts with 1.2.3-trione-2-arylhydrazones 2a, c, e, f and i to yield the corresponding isoxazole derivatives 6a–e or 7a–e. The 2-arylhydrazones 2a, c, d, e, h and i form the corresponding pyrazole derivatives 8a–f when treated with semicarbazide hydrochloride.

Mathematical Heritage of Zambia.

Abstract: The students asked questions about how a person knew his age and how it was determined; how long and short periods of time were determined; how long and short distances were measured; how volumes of oil or beer were measured; how trade was transacted; how quantities of foodstuffs were measured; how people measured to build their houses; how records were kept; and how obligations were fulfilled. The answers varied according to the area of Zambia where the student collected his information. There were also many similarities because many of the tribes have a common language root, and the tribes live in contact with one another.

Yttrium-90 in gonads of monkeys containing strontium-90.

Abstract: THE distribution of 91Y and 90Y in tissues after intravenous injection of 91Y or of 90Y + 90Sr has been reviewed1,2. This information is not very helpful in understanding the transfer of 90Y from bone into soft tissues because of the overwhelming contribution of the directly injected Y. But if a mixture of 90Sr and 90Y is injected intramuscularly, 90Sr is free to diffuse into the blood stream but the injected 90Y is almost immobilized locally. The 90Sr is largely taken up into the bones and in these circumstances soft tissue content of 90Y may be an index of transport of 90Y formed in bone out of bone and into the blood stream.