Swartkrans as a case study in African cave taphonomy

Main articleBy taphonomy is meant the systematic study of death assemblages of once-living things in this case of vertebrate animals. Such study may have various aims but in the present instance my objective has been the interpretation of bone assemblages in the Swartkrans cave to throw light on such topics as: 1. the ways in which bones found their way to the cave; 2. the nature of the animal communities which contributed bones to the assemblages and the kind of environment in which the communities lived; 3. the behaviour of the hominids and other animals whose bones form part of the fossil assemblage. Swartkrans, though not a particularly large cave, is one of considerable complexity and can be used as a case study to illuminate several principles in African cave taphonomy. Three of these principles are discussed.Non

The contribution of Alun R. Hughes to the early development of cave taphonomy: a tribute

Tribute to Alun R. Hughe

The 3D Spin Geometry of the Quantum Two-Sphere

We study a three-dimensional differential calculus on the standard Podles quantum two-sphere S^2_q, coming from the Woronowicz 4D+ differential calculus on the quantum group SU_q(2). We use a frame bundle approach to give an explicit description of the space of forms on S^2_q and its associated spin geometry in terms of a natural spectral triple over S^2_q. We equip this spectral triple with a real structure for which the commutant property and the first order condition are satisfied up to infinitesimals of arbitrary order.Comment: v2: 25 pages; minor change

Presidential address: taphonomy as an aid to African palaeontology

Presidential address for PSSA conferencePalaeontology has its roots in both the earth and life sciences. Its usefulness to geology comes from the light which the understanding of fossils may throw on the stratigraphic relationships of sediments, or the presence of economic deposits such as coal or oil. In biology, the study of fossils has the same objectives as does the study of living animals or plants and such objectives are generally reached in a series of steps which may be set out as follows.Non

The importance of Nama Group sediments and fossils to the debate about animal origins

Main articleThe purpose of this review is to draw attention to the contribution that Nama sediments and fossils have made, and potentially can make, to the ongoing debate about metazoan origins. Two important features of this debate concern the nature and systematic position of the late Proterozoic "Ediacaran" fauna as well as the reasons for the sudden appearance in the fossil record of representatives of almost all known animal phyla, during the Early-Middle Cambrian radiation. An additional vexing question is the reason for the apparent absence of preserved representatives of ancestral metazoan lineages in Proterozoic sediments, despite the fact that molecular evidence shows that such lineages had a long his tory, prior to Cambrian times. Nama fossils and their enclosing sediments have made crucial contributions to this debate and will surely continue to do so in the future.The Foundation for Research Development in Pretoria

The ADHM Construction of Instantons on Noncommutative Spaces

We present an account of the ADHM construction of instantons on Euclidean space-time $\mathbb{R}^4$ from the point of view of noncommutative geometry. We recall the main ingredients of the classical construction in a coordinate algebra format, which we then deform using a cocycle twisting procedure to obtain a method for constructing families of instantons on noncommutative space-time, parameterised by solutions to an appropriate set of ADHM equations. We illustrate the noncommutative construction in two special cases: the Moyal-Groenewold plane $\mathbb{R}^4_\hbar$ and the Connes-Landi plane $\mathbb{R}^4_\theta$.Comment: Latex, 40 page

A study of the effects of micro-gravity on seed germination

This study will identify characteristics of seed germination dependent upon gravity. To accomplish this objective, four different seed types will be germinated in space and then be compared to a control group germinated on Earth. Both the experimental and control groups will be analyzed on the cellular level for the size of cells, structural anomalies, and gravitational effects. The experiment will be conducted in a Get Away Special Canister (GAS Can no. 608) owned by the U.S. Space and Rocket Center and designed for students. The GAS Can will remain in the cargo bay of the Space Shuttle with minimal astronaut interaction

Summary of experiments.

(I) General comments and highlights. (II) Scald: Fungicidal control. 82BA21, 82E18, 82MT19, 82WH23, 82WH23. (III) Scald: Opportunity trial on fungicidal control. 82AL85, 82BA22, 82MT20. (IV) Scald: Epidemic in segregating populations. (V) Scald: Host reaction in hill plots and single plants. 82MT21, 82BA23, (VI) Scald: Seeding rate in evaluating cultivars for resistance. 82MT22, (VII) Net-type net blotch: Screening fungicides. 82BA25, 82KA25. (VIII) Net-type net blotch: Reactions in single plants and hill plots. 82A3, 82BA26. (IX) Spot-type net blotch: Screening fungicides. 82C16. (X) Spot-type net blotch: Potential yield losses. 82C14, 82C15. (XI) Effect of simulated stubble mulching on disease and yield. 82BA36, 82BA35, 82C32, 82MT43,82N27. (XII) Maximising barley yield: Fungicide x growth regulator x cultivar. 82E19,. (XIII) Maximising barley yield: Fungicide x cultivar x nitrogen. (XIV) Variation in pathogenicity of scald, net blotch and powdery mildew. (XV) Unidentified leaf spot on forrest barley. (XVI) Opportunity trial on powdery mildew

Surface Morphology of Human Airway Mucosa: Normal, Carcinoma or Cystic Fibrosis

The study presents preliminary qualitative findings of an investigation of grossly normal main and lobar bronchi at sites distant to well circumscribed tumour (n=15), adjacent to tumour (n=5) or of airways obtained during heart/lung transplantation in patients with cystic fibrosis (CF, n=3). In the normal airways the surface epithelium was on average 50 m thick, pseudostratified and rested on a roughly contoured basement membrane. A variety of cell types were identified although many were obscured by a dense covering of cilia, occasionally interrupted by foci of squamous metaplasia. Submucosal gland structure was observed in chance vertical fractures of the airway wall. Tissue adjacent to tumour showed sloughing, squamous metaplasia, pleomorphism and cell surface projections of stubby microvilli or tortuous microridges. The surface morphology of the three CF patients showed no feature unique to the condition, albeit secretions were found adherent to surface lining associated with isolated bacteria and groups of free cells (probably lymphocytes). In each of the three cases the epithelial surface was densely ciliated, interspersed with mucous (i.e., goblet) cells. Submucosal gland collecting ducts had dilated lumena

Barley foliage diseases

General comments and highlights Scald: Effect of time of application - 83BA10, 83MT9. Scald: Effect of rate of fungicide – 83BA11. Scald: Comparing fungicides – 83BA42. Scald: Effect of seeding rate – 83BA12, 83MT10. Scald: Response to fungicide in farmer\u27s field – 83AL18, 83AL81, 83AL82. Scald: Variation in pathogenicity – 83AB11, 83BA13, 83MT11, 83WH7. Scald: Cultivar x fungicide in farmer\u27s field – 83LG63. Net Blotch: Potential yield losses – 83A15, 83BA15, 83WH6. Net Blotch: Screening new fungicides – 83BA43. Spot-type net blotch: Potential yield losses – 83C5. Spot-type net blotch: Sources of resistance - Chapman Research Station, Nabawa. Powdery mildew fungicide x growth regulator – 83E5. Powdery mildew Cultivar x fungicide x nitrogen – 83E6. Powdery mildew Response to fungicide in farmer\u27s crops (Esperance) – 83ES4, 83ES5, 83ES50, 83ES51, 83ES52, 83ES53. Note that ES52 was abandoned and only disease data are available from ES4. Powdery mildew Response to fungicide in farmer\u27s crops (Albany) – 83AL80, 83AL83. Powdery mildew Screening fungicides – 83PE53