A revision of the 2004 growth potential of towns in the Western Cape study

CITATION: Van Niekerk, A., Donaldson, R., Du Plessis, M. & Spocter, M. 2010. A revision of the 2004 growth potential of towns in the Western Cape study. Stellenbosch University.One of the objectives of the Department of Environmental Affairs and Development Planning (DEA&DP) is to undertake spatial planning that promotes and guides the sustainable future development of the Western Cape province and redresses spatial inequalities. This goal led to the development of the Provincial Spatial Development Framework (PSDF), which identifies the areas of growth in the province and the areas where, in terms of the sustainable development paradigm, growth should be emphasised in the future. It also addresses the form that this growth or development should take and further emphasises the restructuring of urban settlements to facilitate their sustainability. To provide guidance and support for implementing the PSDF, a thorough understanding and knowledge of the characteristics and performances of all the settlements in the province is needed

A macro analysis and GIS application of urban public space closures in Cape Town, 1975 - 2004

Citizens in Cape Town have been claiming urban public space for private use since the 1970s. This article endeavours to trace the extent, identify patterns and investigate the processes utilised by citizens in the claiming of urban public space in the city. This article aims to add to the growing corpus of knowledge on the erosion of urban public space by focussing on the micro, erf-sized level, by seeking to understand the history of the erosion of urban public space as entrenched in legislation and to highlight the impact that indi-vidual citizens, not major real estate developers or large organisations, can have on the shaping of urban public space within the urban landscape

Gated developments: international experiences and the South African context

Gated developments, more commonly known as gated communities, have become a feature of urban living throughout the world. Gated developments in South African cities are an ubiquitous feature of the contemporary urban landscape with many new housing developments in the form of secure estates or fortified town house complexes. A review of international research on gated developments reveals four broad themes into which such research can be placed. South African gated development research is discussed within these themes and it is found that the themes are present in varying degrees in South Africa. This highlights not only global commonalities in gated development research, but also the importance of local or regional conditions in facilitating the increased proliferation of gated developments

The Panglossian Paradigm revisited : The role of non adaptive mechanisms in hominid brain and body size evolution

The largely dominant adaptationist argument is currently used as the framework within which hominid brain evolution is explained; however these adaptationist explanations are inherently problematic and only suffice to ‘clutter’ our knowledge of the possible causes of hominid brain evolution. This study addresses the caveats observed in the fossil record and aims to assess the relative influence of structural laws of form, phylogenetic constraints, and adaptive factors during the course of primate and hominid brain evolution. A combination of methods such as variance partitioning, phylogenetic regression procedures and path analysis indicate that constraints have played a critical role in the scaling attributes of the primate and hominid brain. In particular, developmental constraints governing the scaling attributes of the skull and body are shown to explain up to 50 % of the variation in body mass whereas phylogenetic constraints are purported to have played a lesser role (i.e. 0.8 -3.6 %). In addition, the scaling attributes of neural and non-neural components of the cranial vault suggest a highly constrained suite of traits and suggest that as much as 96 % of the variation in both brain mass and residual endocranial space may be explained by correlated scaling with the cranial vault. Constraints are observed to be far more pliable than traditionally thought – a feature highlighted by intraspecific analyses of scaling attributes in humans. Low regression coefficients typical reported for intraspecific curves are shown to arise during development as greater variation in body parameters is allowed with advancing age. Grade shifts in the scaling of brain and body size for primates and other mammalian orders is also emphasised by this current study and it is argued that correlated changes between the brain and body size may not necessarily impact upon the ‘complexity’ of the neural system as the functional integrity may be maintained via higher output states initiated at certain levels of organisation such as at the level of the cortical area. Although constraints should rightfully be given greater coverage in explanations concerning hominid brain expansion, it is only through implementation of research protocols that take a pluralistic approach to an understanding of the role of both constraints and adaptation in the formation of the brain that our interpretation of the likely mechanism for hominid brain expansion may be understood

The Complexly Parcellated, Yet Quantitatively Reduced, Orexinergic/Hypocretinergic System of Humans.

The phylogenetic contextualization of human neuroanatomy is crucial for understanding the positive, neutral, and/or negative effects of therapeutic interventions derived from animal models. Here we determined the parcellation of, and quantified, orexinergic (or hypocretinergic) neurons in the hypothalami of humans and several species of primates, including strepsirrhines (two species), platyrrhines (two species), cercopithecoids (three species), and hominoids (three species, including humans). The strepsirrhines, platyrrhines, and cercopithecoids presented with three distinct clusters of orexinergic neurons, revealing an organization like that observed in most mammals. In the three hominoids, an additional orexinergic cluster was found in the tuberal region of the hypothalamus, termed the optic tract cluster extension. In humans only, an additional parvocellular cluster of orexinergic neurons was observed in the dorsomedial hypothalamus. The human presented with the most complex parcellation of orexinergic neurons of the primates studied. Total numbers of orexinergic neurons in nonhuman primates were strongly correlated to brain mass (Puncorr = 1.2 × 10-6), with every doubling in brain mass leading to an ∼1.5-times increase in neuron number. In contrast, humans have approximately 74,300 orexinergic neurons, which is significantly less than the 205,000 predicted using the nonhuman primate regression for a brain mass of ∼1363 g. We conclude that although the human orexinergic system is the most complex of primates in terms of parcellation, with potential associated functional specializations, this system is quantitatively paradoxical in having a significantly lower neuronal number than expected for a primate with an ∼1363-g brain

Organization of the sleep‐related neural systems in the brain of the harbour porpoise (Phocoena phocoena)

The present study provides the first systematic immunohistochemical neuroanatomical investigation of the systems involved in the control and regulation of sleep in an odontocete cetacean, the harbor porpoise (Phocoena phocoena). The odontocete cetaceans show an unusual form of mammalian sleep, with unihemispheric slow waves, suppressed REM sleep, and continuous bodily movement. All the neural elements involved in sleep regulation and control found in bihemispheric sleeping mammals were present in the harbor porpoise, with no specific nuclei being absent, and no novel nuclei being present. This qualitative similarity of nuclear organization relates to the cholinergic, noradrenergic, serotonergic, and orexinergic systems and is extended to the γ-aminobutyric acid (GABA)ergic elements involved with these nuclei. Quantitative analysis of the cholinergic and noradrenergic nuclei of the pontine region revealed that in comparison with other mammals, the numbers of pontine cholinergic (126,776) and noradrenergic (122,878) neurons are markedly higher than in other large-brained bihemispheric sleeping mammals. The diminutive telencephalic commissures (anterior commissure, corpus callosum, and hippocampal commissure) along with an enlarged posterior commissure and supernumerary pontine cholinergic and noradrenergic neurons indicate that the control of unihemispheric slow-wave sleep is likely to be a function of interpontine competition, facilitated through the posterior commissure, in response to unilateral telencephalic input related to the drive for sleep. In addition, an expanded peripheral division of the dorsal raphe nuclear complex appears likely to play a role in the suppression of REM sleep in odontocete cetaceans. Thus, the current study provides several clues to the understanding of the neural control of the unusual sleep phenomenology present in odontocete cetaceans. J. Comp. Neurol. 524:1999-2017, 2016. © 2016 Wiley Periodicals, Inc

A Comparative Perspective on Minicolumns and Inhibitory GABAergic Interneurons in the Neocortex

Neocortical columns are functional and morphological units whose architecture may have been under selective evolutionary pressure in different mammalian lineages in response to encephalization and specializations of cognitive abilities. Inhibitory interneurons make a substantial contribution to the morphology and distribution of minicolumns within the cortex. In this context, we review differences in minicolumns and GABAergic interneurons among species and discuss possible implications for signaling among and within minicolumns. Furthermore, we discuss how abnormalities of both minicolumn disposition and inhibitory interneurons might be associated with neuropathological processes, such as Alzheimer's disease, autism, and schizophrenia. Specifically, we explore the possibility that phylogenetic variability in calcium-binding protein-expressing interneuron subtypes is directly related to differences in minicolumn morphology among species and might contribute to neuropathological susceptibility in humans

Species-specific distributions of tyrosine hydroxylase–immunoreactive neurons in the prefrontal cortex of anthropoid primates

In this study, we assessed the distribution of cortical neurons immunoreactive for tyrosine hydroxylase (TH) in prefrontal cortical regions of humans and nonhuman primate species. Immunohistochemical methods were used to visualize TH-immunoreactive (TH-ir) neurons in areas 9 (dorsolateral prefrontal cortex) and 32 (anterior paracingulate cortex). The study sample included humans, great apes (chimpanzee, bonobo, gorilla, orangutan), one lesser ape (siamang), and Old World monkeys (golden guenon, patas monkey, olive baboon, moor macaque, black and white colobus, and François' langur). The percentage of neurons within the cortex expressing TH was quantified using computer-assisted stereology. TH-ir neurons were present in layers V and VI and the subjacent white matter in each of the Old World monkey species, the siamang, and in humans. TH-ir cells were also occasionally observed in layer III of human, siamang, baboon, colobus, and François' langur cortex. Cortical cells expressing TH were notably absent in each of the great ape species. Quantitative analyses did not reveal a phylogenetic trend for percentage of TH-ir neurons in these cortical areas among species. Interestingly, humans and monkey species exhibited a bilaminar pattern of TH-ir axon distributions within prefrontal regions, with layers I–II and layers V–VI having the densest contingent of axons. In contrast, the great apes had a different pattern of laminar innervation, with a remarkably denser distribution of TH-ir axons within layer III. It is possible that the catecholaminergic afferent input to layer III in chimpanzees and other great apes covaries with loss of TH-ir cells within the cortical mantle

Orexinergic bouton density is lower in the cerebral cortex of cetaceans compared to artiodactyls

The species of the cetacean and artiodactyl suborders, which make up the cetartiodactyl order, have very different arousal thresholds and sleep-wake systems. The aim of this study was to determine whether cetaceans or artiodactyls have differently organized orexinergic arousal systems by examining the density of orexinergic innervation to the cerebral cortex. This study provides a comparison of orexinergic bouton density in the cerebral cortex of twelve cetartiodactyl species by means of immunohistochemical staining and stereological analysis. It was observed that the morphology of the axonal projections of the orexinergic system to the cerebral cortex was similar across all species, as the presence, size and proportion of large and small orexinergic boutons were similar. Despite this, orexinergic bouton density was lower in the cerebral cortex of cetaceans compared to artiodactyls, even when corrected for brain mass, neuron density, glial density and glial: neuron ratio. Glial density was identified as the major determinant for the observed differences. It appears a synergy exists between the orexinergic neurons and their projections, glial cells, and the biochemical correlates of appetitive drive and arousal, but further studies need to be performed to understand the full extent of the orexinergic system and its role in sustained arousal.This work was mainly supported by funding from the South African National Research Foundation (P.R.M., N.C.B.) and by a fellowship within the Postdoctoral-Program of the German Academic Exchange Service, DAAD (N.P.). The work was also supported by an IOER R&G Grant from Des Moines University (#12- 13-03) (M.A.S.), Reykjavik University 2010 Development Fund (K.Æ.K.), the Deanship of Scientific Research at the King Saud University through the research group project number RGP_020 (A.N.A., O.B.M.), and NIH grant DA 2R01MH064109 and the Department of Veterans Affairs (J.M.S).http://www.elsevier.com/locate/jchemneu2016-10-31hb2016Mammal Research InstituteZoology and Entomolog