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Grahamstown, South Africa

Rhodes University is a public research university located in Grahamstown in the Eastern Cape Province of South Africa, established in 1904. It is the province's oldest university, and is one of the four universities in the province. It is the fifth or sixth oldest South African university in continuous operation, being preceded by the University of the Free State , University of Witwatersrand , Stellenbosch University and the University of Cape Town . Rhodes was founded in 1904 as Rhodes University College, named after Cecil Rhodes, through a grant from the Rhodes Trust. It became a constituent college of the University of South Africa in 1918 before becoming an independent university in 1951.The university has an enrolment of over 7,000 students, approximately 3,000 of whom live on campus in several residences located on campus while the remaining students take residence in digs or in their own homes in town. Wikipedia.

This chapter discusses the electronic absorption spectra and electrochemistry of phthalocyanine complexes which are redshifted to ∼730 nm and beyond. These are mainly manganese phthalocyanine derivatives and phthalocyanines containing sulfur substituents. The chapter concentrates mainly on the work done during the last 10 years. There are 96 references quoted and three detailed tables on the electronic absorption spectra, redox potentials, and analytes that are electrocatalyzed using manganese and titanium phthalocyanine complexes. © Springer-Verlag Berlin Heidelberg 2010. Source

Barnes R.S.K.,Rhodes University
Marine Ecology Progress Series

The magnitude and patchiness of macrobenthic biodiversity were compared across spatial scales spanning 5 orders of areal magnitude (ca. 2 m2 to ca. 1.5 ha) in an intertidal seagrass bed in the warm-temperate Knysna estuarine bay, South Africa. The 75 component species and their populations were highly variably distributed across the site, abundances of the individual dominant animals being significantly patchy and composition of the macrofaunal assemblage being significantly non-uniform. Nevertheless, emergent assemblage attributes exhibited spatial constancy: values of assemblage metrics (faunal abundance, species richness, species density and species diversity) did not differ across the site or across spatial scales, and neither did the patterns of dispersion of species diversity, species richness or observed species density. Distribution of the 2 latter through space was even significantly uniform. Ecological arguments developed for temporal constancy of biodiversity seem broadly applicable to the spatial dimension at Knysna, suggesting that although apparently paradoxical, it may be the varying assemblage composition that permits this spatial stability. There is no evidence, however, that the Knysna seagrass macrobenthos is a competitively-structured assemblage with rigid niche-partitioning, a condition suggested to be necessary for temporal constancy; rather, it is more likely to be open, non-equilibrium and below carrying capacity. © Inter-Research 2013. Source

The 40th anniversary of the initial development of the Pitman rainfall-runoff (developed in South Africa and widely applied throughout southern Africa) approximately coincides with the end of the IAHS PUB programme and the start of a new decade focussing on hydrological change (Panta Rhei) and society. The paper reviews the developments and applications of the Pitman model in the context of the appropriate outcomes of PUB and the proposed future directions of Panta Rhei. The focus of development of the Pitman model has been dominated by practical applications, while PUB was largely dominated by science issues. While some of the PUB principles have been applied with the Pitman model, there are others that are deemed inappropriate for practical modelling and others that would almost certainly benefit the Pitman model applications in the future. The paper includes discussions of the model structure, input data, parameters and output evaluations - all in the context of uncertainty. The capabilities of the model to address societal development impacts are also discussed and a brief example of an uncertainty approach to applying the model is provided. The conclusions are that some developments of the Pitman model anticipated more recent international developments, while others have not been ignored even if further efforts are required to effectively implement them. Perhaps the largest gap in applying uncertainty principles in practice is how to use them in water resources decision making. © 2013 Elsevier B.V. Source

In 2001 Marc Prensky coined the phrase 'digital natives' to refer to the new generation of students who have grown up surrounded by technology. His companion papers spurred large amounts of research, debating changes that are required to curricula and pedagogical models to cater for the changes in the student population. This article reports on a study conducted in 2009 of more than 290 first year students at two South African universities. In this study, students were asked about their access to and use of technology. The results portrayed a heterogeneous student population, with varying levels of access to and use of most technologies. One of Prensky's key features of a digital native is their excitement with Web 2.0 based technologies. Participants in this study however, appear not to use such technologies, and to not be interested in using them in their studies. One tool that students had high levels of access to (98.1%), and use of is the mobile phone. Out of all uses of technology surveyed, tasks involving the mobile phone were ranked in the top two positions. Also when asked to rank different uses of technology particularly for their studies, three of the top five uses relied on a mobile phone. © 2010 Elsevier Ltd. All rights reserved. Source

There is a large body of information relating to the ontogeny, development and the vasculature of eudicotyledonous leaves. However, there is less information available concerning the vascular anatomy of monocotyledonous leaves. This is surprising, given that there are two uniquely different phloem systems present in large groups such as grasses and sedges. Monocotyledonous leaves contain marginal, large, intermediate, and small longitudinal veins that are interconnected by numerous transverse veins. The longitudinal veins contain two metaphloem sieve tube types, which, based upon their ontogeny and position within the phloem, are termed early (thin-walled) and late (thick-walled) sieve tubes. Early metaphloem comprises sieve tubes, companion cells and vascular parenchyma (VP) cells, whilst the late metaphloem, contains thick-walled sieve tubes (TSTs) that lack companion cells. TSTs are generally adjacent to, or no more than one cell removed from the metaxylem. Unlike thin-walled sieve tube (ST) -companion cell complexes, TSTs are connected to parenchyma by pore-plasmodesma units and are generally symplasmically isolated from the STs. This paper addresses key structural and functional differences between thin- and thick-walled sieve tubes and explores the unique advantages of alternate transport strategies that this 5-7 million years old dual system may offer. It would seem that these two systems may enhance, add to, or play a significant role in increasing the efficiency of solute retrieval as well as of assimilate transfer. © 2013 Botha. Source

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