The potential of Grateloupia filicina (Lamoureux) J. Agardh. for mariculture: Culture experiments and observations on shore phenology
Grateloupia filicina is a carrageenophytic red alga which is in demand as a carrageenan raw material and for use in food. There is therefore interest in developing a technique for mariculturing this species. Since vegetative propagation from thallus fragments has not been successful, the present study was initiated to determine suitable conditions for spore liberation and growth of G. filicina from spores. It was also attempted to propagate G. filicina sporelings from crust and thallus fragme...
A Report On Me Invasive Status Of Pinus Patula On Mount Mulanje, Mala Wi.
Natural regeneration of the Mexican weeping pine Pinus patula on Mt. Mulanje was investigated and found to represent a serious threat to the natural vegetation, with the invasion already advanced on the north eastern plateaux. Various aspects of the biology of the pine are related to its success as an exotic invader on the mountain. Perhaps most important is the ability of the species to cope with fire, and the role of regular fires in enhancing the invasion. Urgent action is needed ...
Some Observations on the genus At~ocnemum
Only in 1954 the notes of late Prof. Moss on the genera Arthrocnemum and Salicornia l'Tere published, and although this was a big step forward in the classification of these genera, it proved to be unsatisfactory in many cases. This, however, should not throw the work on that subject done by him into shade, as shows his ealier works ( Moss, 19lo, 1912, 1914),and only his notes published by Prof. Adamson in 1954 w·ere unfortunately fragmentary. The revision of the genus Arthrocnemum is taken ...
Three Species Of The Genus Rhabdosargus Fowler, With Special Reference To The Ffwhite Stumpnose", R.Globiceps (Cuvier)
The Zoology Department of the u.c.T. has been making an ecological survey of South Afr1,can estuaries. The plant and animal lif'e of many estuaries has been studied in relation to physico-chemical conditions, and bottom fauna has been dealt with in great detail. Not much is known about the fish populations that occupy these estuaries. It was theref'·ore decided that some information about typical estuarine fish might be of use. For the first four months nettings were made at two estuaries ne...
"The Benthi~Ecology o~ FaJise Bay, w.ith Notes on the Analysis o~ Shallow-water So~t SUbstrata
This work continues the marine tradition o~ the Department o~ Zoology but attempts to open-up a new ~ield by tack].ing for· the first time the ecology of the shaJllow sea bed. False Bay is accessible and provides a large arem that is virtually unaffe.cted by rivers or the works of man. Its' situation happ:ens to be particularly _interesting. It is the nearest part of the flat, submarine shelf called the Agulhas Bank, where there are valuable fishing grounds: and it lies at the boi.mdary of t...
The Geology And Geochemistry Of The Etendeka Formation Quartz Latites, Namibia.
The Etendeka Formation volcanics of north-western Namibia form part of the Karoo Igneous Province of southern Africa and consist of a series of basalts interbedded with quartz latites and minor volumes of latite. This thesis examines various aspects of the geology and geochemistry of the quartz latites, in particular the volcanological and petrogenetic origin of these rocks . This study has involved the geological mapping of ca. 5000 km2 of the southern Etendeka region and the documentation o...
A Tax~Omic And Lf.Pidological Study. Of ''Lhe .South African Heterosoma Ta With Special R.Eference To The Value Of Scale Characters • In Identification Amd Classification
During the course of some years of research into growth-rate and age of South African fishes of commercial importance, amongst wbich are included various species of Heterosomata, 1 the scales of sucb species received a great deal of attention.· In a very short time the characteristics of the sea les thus . examined became so familiar, that it was found poseible to identify any particular species solely from its scales. In a great many instances scale-samples, labelled with the local common n...
The Hydroclimate Variability of Central Africa: seasonal cycle, mechanisms, teleconnections and impacts on neighbouring regions
Abstract Central Africa is, climatologically speaking, a poorly studied region (Clivar, 2000; Dezfuli and Nicholson, 2012; Nicholson and Dezfuli, 2012; Todd and Washington, 2004). It is considered as a knowledge gap in the understanding of the tropical climate system (Todd and Washington, 2004). Drivers of Central Africa rainfall are not well documented and deserve more attention. The aims of thesis are to enhance our fundamental understanding of Central Africa rainfall and the mechanisms inv...
TECTONIC AND SEDIMENTARY HISTORY OF THE MID NATAL VALLEY (S.W. INDIAN OCEAN)
ABSTRACT The Natal Valley is a sediment-filled marine basin situated between the east coast of southern Africa (Natal) and the Mozambique Ridge. Geophysical and sedimentological t~chniques are used in a broad geological study of the mid Natal Valley. Major emphasis is directed to: (a) basin history and tectonic evolution; (b) seismic stratigraphy of the basin fill; (c) recent sedimentary processes and responses. General basin morphology is defined by five major physiographic provinces: contin...
A NOTE ON AN ABNORMAL XENOPUS LAEVIS SPECIMEN WITHOUT HAEMOGLOBIN and on some~eriments performed as a consequence.
In the blood vascular system of a typical fish, the blood is sent from the heart to the gills for oxygenation and thence to the rest of the tissues, before returning once more to the heart. This is a so-called "Single Circulation". Where lungs make their appearance in the vertebrate series however, their blood supply is derived from the last of the aortic arches and is returned via the newly formed pulmonary veins, directly to the heart. A part of the blood leaving from the heart is sent to t...
The Application Of Multivariate Statistical Techniques In The Analysis Of Stock Market Data
Securities were first traded in the sixteenth century and it is reasonable to assume that si~ce that time investors have always devoted attention to research into the relative merits and demerits of individual stock market ventures. In the nineteenth and twentieth centuries, ma~ has placed increasing emphasis on numerical and statistical analysis, and it was only a matter of time before these two related approaches focussed their attention on the problems of stock market research. As early as...
General Relativity and Penrose process
Abstract Using the concept of parallel transport of vectors in curved manifolds, the Riemann curvature tensor in terms of Christoffel symbols is obtained. Making use of the Riemann curvature tensor’s symmetry properties, the Ricci curvature tensor and Einstein’s tensor are derived. Through Einstein’s tensor and the Poisson equation for Newtonian gravity, the Einstein field equations are introduced. Upon using Kerr metric (Kerr, 1963) as a solution for Einstein’s field equations, extra...
Understanding and Supporting Pricing Decisions using Multicriteria Decision Analysis: An Application to Antique Silver in South Africa
Abstract This dissertation presents an application of multicriteria decision analysis to understand and support pricing decisions in fields where goods are unique and described by their characteristics. The specific application area of this research is antique silver objects, where a complete iteration of the multicritia decision process is performed. This includes two problem structurings using SODA which provide rich detail into this application area. Multi-attribute additive models are con...
Sequential Nonparametric Estimation via Hermite Series Estimators
Abstract Sequential Nonparametric Estimation via Hermite Series Estimators Michael Jared Stephanou Algorithms for estimating the statistical properties of streams of data in real time, as well as for the efficient analysis of massive data sets, are becoming particularly pertinent given the increasing ubiquity of such data. In this thesis we introduce novel approaches to sequential (online) estimation in both stationary and non-stationary settings based on Hermite series density estimators. In...
Community-Based Co-Design of a Crowdsourcing Task Management Application for Safeguarding Indigenous Knowledge
Teaching indigenous knowledge (IK) to African youth has become more complicated due to a variety of reasons such as urban migration, loss of interest in it, the dominance of scientific knowledge and the technological revolution. Therefore, there is a considerable movement towards using technologies to safeguard IK before it becomes obsolete. It is noteworthy that research conducted and software development perspectives being used are mainly based on Western worldviews that are inappropriate f...
