Biogeographical Principles in Horticulture

With more than 780 species, Erica is the largest genus in the Core Cape Subregion, once referred to as the Cape Floristic Region (CFR), in South Africa. The redevelopment of the Erica Display Garden at Kirstenbosch National Botanical Garden to fulfil aesthetic, conservation and educational purposes is described. The author draws on decades of field work in the CFR to open a window for botanic garden visitors and schoolchildren who have not had the privilege of experiencing the unique flora of the CFR. An explanation for the extraordinary diversity of the CFR is explored. The challenge of engaging with visitors and at the same time highlighting the diversity of ericas and fynbos while overcoming the difficulties of growing wild species out of their natural and niche habitats is explained. The most effective way to display South African ericas and fynbos is discussed. The use of phytogeographical themes is preferred as a suitable method to display diversity in botanic garden horticulture. Nine planting beds totalling 8,000 m2 were redeveloped to represent six distinct phytogeographic regions identified in Plants of the Greater Cape Floristic Region (Manning & Goldblatt, 2012). Nineteen of the twenty largest families and genera of the Cape flora are also represented in these displays. Interpretation was created to provide information on the defining features of each region. The phytogeographic theme was used to emulate typical natural floristic features of each and to bring the concept of geographically driven plant diversity to the attention of the visiting public and students

The Restoration of Erica verticillata

The Threatened Species Programme at the South African National Biodiversity Institute, Kirstenbosch National Botanical Garden, is integrated to include both ex situ and in situ conservation activities. Plant conservation is driven by South Africa’s Strategy for Plant Conservation which was developed in response to the Global Strategy for Plant Conservation. This case study examines the conservation of Erica verticillata (whorl heath), a flagship for threatened species at Kirstenbosch, and documents the integration of ex situ with in situ conservation at three areas on the Cape Flats. The whorl heath was thought to be extinct by 1950. Horticulturists have since rediscovered eight clones in botanic gardens worldwide, the Heather Society and commercial growers. Ex situ conservation in botanic garden collections and the Millennium Seed Bank has since allowed in situ conservation in the critically endangered Cape Flats Sand Fynbos vegetation type. The process of restoring the whorl heath presented many challenges. Initially attempts were hampered by limited available knowledge on suitable niche habitats. Pioneering work carried out at Rondevlei Nature Reserve identified the suitable habitat and this was applied in subsequent in situ work at Kenilworth Racecourse Conservation Area and at Tokai Park – the only natural areas remaining in or near this species’ historical distribution range. Successful re-establishment of this species depends upon its capacity to recruit after fire, which is an essential ecological process in the fynbos. Many clones have been in cultivation for a long time and are poor seed producers: seed production was first recorded at Rondevlei only after additional clones were planted together. Only one population (Rondevlei) to date has seen a fire and thus has recruited seedlings; however these are competing with vigorous companion plants. The study continues and is currently exploring the role of herbivory in the restoration process. The key lesson learnt to date is the need to include sustainable management of the entire ecosystem in the restoration process and not limit it to single species. Success in restoring a species depends upon a healthy stand of the vegetation type in place, along with pollinators and other key fauna and other natural ecosystem processes. It is recommended that successful re- establishment of a species in fynbos requires the reintroduced population to survive three fire cycles

Hyperspaces of uniform spaces

This thesis is concerned with the properties and uses of the so-called Hausdorff uniform structure on the set of subsets of a uniform space. Sometimes the results are for more specialised spaces - metric spaces, normed spaces or topological vector spaces, or for the more general proximity spaces. Historically the hyperspace has probably derived its importance mainly from the concept of hypercompleteness. Here a study is made of hyperspaces of Hausdorff completions and Hausdorff completions of hyperspaces, and, in particular, of a case where these spaces derive from two related uniform structures on a set. Certain Hausdorff completions are shown to be uniformly embedded in the 'hyperhyperspace', and some generalisations are proved of results of the Robertsons on sets of compact subsets. Making a completely different approach, J. L. Kelley's notion of a fundamental family of subsets is applied to uniform spaces and the Hausdorff completion of the hyperspace is constructed by means of fundamental families. A study is made of two conditions on a mapping between uniform spaces, the filter condition, introduced by Dr. Wendy Robertson, and the analogous fundamental family condition, which bears a relationship to hypercompleteness similar to that of the filter condition to completeness. Another subject which has attracted some interest recently is the comparability of the topologies induced on the set of subsets by various uniform structures on the original set. A survey of known results is given and the relationships between them are discussed. The question of when two uniform structures induce the same topology on sets of subsets of particular kinds is investigated, and finally a new condition is provided for a uniform structure to be unique in the sense that no other uniform structure on the given set can induce the same topology on the set of subsets. The last two chapters deal with properties of mappings and sets of mappings, introducing two new concepts - the hypergraph of a mapping and a hypercompact set of mappings. The properties of the hypergraph are related to continuity and uniform continuity, giving rise to theorems similar to closed graph theorems. Hypercompactness is studied in relation to compactness and collective compactness of sets of mappings

Interview with Anthony Deluliis

The interview discusses the process by which high schools use the Alternative Center with Anthony DeIuliis, Principal of Fredricktown High Schoolhttps://digital.kenyon.edu/ae_interviews/1003/thumbnail.jp

On Speleosiro argasiformis—a troglobitic Cyphophthalmi (Arachnida: Opiliones: Pettalidae) from Table Mountain, South Africa

We report the recent collection and observation of large numbers of specimens of the troglobitic harvestman Speleosiro argasiformis Lawrence 1931 in the Wynberg Cave system, Table Mountain, South Africa. Specimens were collected and/or photographed in different caves of the system. Live observation showed specimens fleeing bat carcasses when disturbed.Organismic and Evolutionary Biolog

Low rank approximation of multidimensional data

In the last decades, numerical simulation has experienced tremendous improvements driven by massive growth of computing power. Exascale computing has been achieved this year and will allow solving ever more complex problems. But such large systems produce colossal amounts of data which leads to its own difficulties. Moreover, many engineering problems such as multiphysics or optimisation and control, require far more power that any computer architecture could achieve within the current scientific computing paradigm. In this chapter, we propose to shift the paradigm in order to break the curse of dimensionality by introducing decomposition to reduced data. We present an extended review of data reduction techniques and intends to bridge between applied mathematics community and the computational mechanics one. The chapter is organized into two parts. In the first one bivariate separation is studied, including discussions on the equivalence of proper orthogonal decomposition (POD, continuous framework) and singular value decomposition (SVD, discrete matrices). Then, in the second part, a wide review of tensor formats and their approximation is proposed. Such work has already been provided in the literature but either on separate papers or into a pure applied mathematics framework. Here, we offer to the data enthusiast scientist a description of Canonical, Tucker, Hierarchical and Tensor train formats including their approximation algorithms. When it is possible, a careful analysis of the link between continuous and discrete methods will be performed.IV Research and Transfer Plan of the University of SevillaInstitut CarnotJunta de AndalucíaIDEX program of the University of Bordeau

The stories we tell: uncanny encounters in Mr Straw’s house

During my first visit to Mr Straw’s House, a National Trust Property in the North of England, I was intrigued by the discrepancies between the narrative framework provided by the National Trust – its exclusions, silences and invisibilities – and the far more complex stories the house seemed to tantalisingly hint at. As a scholar I am drawn to certain sites and affectively engage with them and yet I usually keep silent about my investment which informs not only my interest but also how I read these heritage sites. My aim here is not primarily to interrogate my own investment, but to ask how productive it is, what it enables me to see and to describe and where its limits are. This case study explores a particular tourist attraction from the perspective of storytelling and asks what narratives can be constructed around, and generated through, the spatial-emotional dimensions of this heritage site. I am interested in the hold sites have over people, why and how they provoke imaginative and empathic investment that generates a network of stories and triggers processes of unravelling which have the potential to transform silences and unmetabolised affect into empathy and emotional thought

A thermostable protein matrix for spectroscopic analysis of organic semiconductors

Advances in protein design and engineering have yielded peptide assemblies with enhanced and non-native functionalities. Here, various molecular organic semiconductors (OSCs), with known excitonic up- and down-conversion properties, are attached to a de novo-designed protein, conferring entirely novel functions on the peptide scaffolds. The protein-OSC complexes form similarly sized, stable, water-soluble nanoparticles that are robust to cryogenic freezing and processing into the solid-state. The peptide matrix enables the formation of protein-OSC-trehalose glasses that fix the proteins in their folded states under oxygen-limited conditions. The encapsulation dramatically enhances the stability of protein-OSC complexes to photodamage, increasing the lifetime of the chromophores from several hours to more than 10 weeks under constant illumination. Comparison of the photophysical properties of astaxanthin aggregates in mixed-solvent systems and proteins shows that the peptide environment does not alter the underlying electronic processes of the incorporated materials, exemplified here by singlet exciton fission followed by separation into weakly bound, localized triplets. This adaptable protein-based approach lays the foundation for spectroscopic assessment of a broad range of molecular OSCs in aqueous solutions and the solid-state, circumventing the laborious procedure of identifying the experimental conditions necessary for aggregate generation or film formation. The non-native protein functions also raise the prospect of future biocompatible devices where peptide assemblies could complex with native and non-native systems to generate novel functional materials

Widespread Contribution of Gdf7 Lineage to Cerebellar Cell Types and Implications for Hedgehog-Driven Medulloblastoma Formation

The roof plate is a specialized embryonic midline tissue of the central nervous system that functions as a signaling center regulating dorsal neural patterning. In the developing hindbrain, roof plate cells express Gdf7 and previous genetic fate mapping studies showed that these cells contribute mostly to non-neural choroid plexus epithelium. We demonstrate here that constitutive activation of the Sonic hedgehog signaling pathway in the Gdf7 lineage invariably leads to medulloblastoma. Lineage tracing analysis reveals that Gdf7-lineage cells not only are a source of choroid plexus epithelial cells, but are also present in the cerebellar rhombic lip and contribute to a subset of cerebellar granule neuron precursors, the presumed cell-of-origin for Sonic hedgehog-driven medulloblastoma. We further show that Gdf7-lineage cells also contribute to multiple neuronal and glial cell types in the cerebellum, including glutamatergic granule neurons, unipolar brush cells, Purkinje neurons, GABAergic interneurons, Bergmann glial cells, and white matter astrocytes. These findings establish hindbrain roof plate as a novel source of diverse neural cell types in the cerebellum that is also susceptible to oncogenic transformation by deregulated Sonic hedgehog signaling