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The article examines the indigenous knowledge of fossil-filled caves in Southern Africa, specifically focusing on the Fossil Hominid Sites of South Africa (FHSSA). While indigenous populations in the region have a deep understanding of the geological environment and the presence of fossils, there is a lack of indigenous knowledge specifically related to fossil-filled caves. The article proposes that cave emergence myths, which are prevalent globally, may actually be referring to these fossil-bearing caves in Southern Africa. This hypothesis is supported by physical evidence such as rock engravings and the cultural significance of caves in the region. The text also highlights the higher concentration of cave emergence myths in southern Africa compared to other parts of the continent, suggesting that the abundance of fossil-rich caves in the area may have influenced the development and perpetuation of these myths. The dominance of these myths in the southern African cultural landscape may be attributed to factors such as indigenous knowledge of the caves and population migrations. [Extracted from the article]

AbstractEucalyptusclones, the ultimate exploitation of genetic variation, are perceived to be the ideal raw material for the pulp mill but is this really true? Their attributes include uniformity, superior pulp properties and faster growth while their only limitation is lack of the natural genetic variation which provides protection against adverse elements. This shortcoming, unless managed, is likely to have a dramatic impact on a mill. Commercial compartments of clones rarely exceed 100ha and are more commonly less than 50ha. The maximum that is planted to an individual clone in one year is 200ha. At an assumed production of 200t/ha this implies that parcels ofup to 10,000t of timber (but more often less) from a single genetic entity will arrive at the mill gate at the same time. Dramatic differences between clones are likely introduce more variation in the form ‘slugs’ than is experienced with seedlings where the variation is more ofa continuous nature. The ten E. grandishybrid clones used commercially by Sappi Forests have been evaluated for wood and dissolving pulp properties across a number of trial sites. Although wood and pulp properties varied between trees within clones, most of the variation was found to occur between clones and, as expected, clones were more uniform than seedlings. Dissolving pulp yield of clones varied from 43.8 to 45.6%, viscosity from 41.4 to 69.8cps and brightness from 43.7 to 50.7. Wood density was found to vary between clones from 460 to 570kg/m3, fibre diameter from 12.05 to 14.49:m and cell wall thickness from 2.40 to 2.64:m. Differences in wood and dissolving pulp properties between and within clones are compared here with E. grandisseedlings, the impacts on daily running of a dissolving pulp mill are discussed and suggestions are provided for management of clones in the mill to make best use of their unique properties.

Pasteurella haemolytica, the causative agent of shipping fever pneumonia in cattle, produces a leukotoxin (LKT) which lyses ruminant leukocytes with high efficiency but is reputed to not affect leukocytes from nonruminant species. In this study, we tested the supposition that LKT binding correlates positively with susceptibility to intoxication of susceptible isolated bovine lymphocytes and lymphoma tissue culture cells (BL3 cells) and negatively with reputed nonsusceptible equine, porcine, and canine lymphocytes and human lymphoid tissue culture cells (Raji cells). Bovine lymphocytes and BL3 cells were highly susceptible to LKT intoxication, exhibiting both substantial increase in intracellular Ca(2+) concentration and marked leukolysis. Exposure of reputed LKT-nonsusceptible porcine lymphocytes and Raji cells to LKT caused a slightly increased intracellular Ca(2+) concentration but no leukolysis. No LKT effect was detected for equine and canine lymphocytes. LKT bound to lymphoid cells from all species tested. Intact 102-kDa LKT was recovered from exposed isolated lymphoid cell membranes. Pro-LKT acylation was not required for LKT binding to BL3 cells. LKT binding was rapid, with maximal binding occurring by 3 min, and was proportional to the LKT concentration in the range 0.04 to 4.0 microg/ml. For this LKT concentration range, BL3 cells bound more LKT than did porcine lymphocytes or Raji cells, suggesting that LKT binds to BL3 cells with higher affinity than to porcine lymphocytes or Raji cells. Above 4.0 microg/ml, LKT demonstrated saturable binding to BL3 cells. Neutralizing anti-LKT monoclonal antibody (MAb) MM601 diminished LKT binding to BL3 by 36% while decreasing leukolysis by 81%. In contrast, MM601 did not diminish LKT binding to Raji cells. Pretreatment of target cells with 120 microg of protease K per ml diminished LKT binding to BL3 cells by 75%, with only a 25% decrease in leukolysis. However, pretreatment with 150 microg of protease K per ml abolished the remaining 25% of LKT binding and 75% leukolysis. Therefore, P. haemolytica LKT binds rapidly to susceptible and to reputed nonsusceptible lymphoid cells. LKT binding resulting in species-specific leukolysis was characterized by high affinity, inhibition by MAb MM601, and relative resistance to protease K pretreatment of lymphoid cells. Two types of LKT binding to lymphoid cells are proposed. High-affinity binding leads to efficient leukolysis. In some lymphoid cells from reputed LKT-nonsusceptible species, low-affinity LKT binding may cause a low-efficiency increase in the intracellular Ca(2+) concentration without leading to leukolysis.

The effects of Pasteurella haemolytica leukotoxin (LKT) on the activity of phospholipase D (PLD) and the regulatory interaction between PLD and phospholipase A(2) (PLA(2)) were investigated in assays using isolated bovine neutrophils labeled with tritiated phospholipid substrates of the two enzymes. Exposure of [(3)H]lysophosphatidylcholine-labeled neutrophils to LKT caused concentration- and time-dependent production of phosphatidic acid (PA), the product of PLD. LKT-induced generation of PA was dependent on extracellular calcium. Both production of PA and metabolism of [(3)H]-arachidonate ([(3)H]AA)-labeled phospholipids by PLA(2) were inhibited when ethanol was used to promote the alternative PLD-mediated transphosphatidylation reaction, resulting in the production of phosphatidylethanol rather than PA. The role of PA in regulation of PLA(2) activity was then confirmed by means of an add-back experiment, whereby addition of PA in the presence of ethanol restored PLA(2)-mediated release of radioactivity from neutrophil membranes. Considering the involvement of chemotactic phospholipase products in the pathogenesis of pneumonic pasteurellosis, development and use of anti-inflammatory agents that inhibit LKT-induced activation of PLD and PLA(2) may improve therapeutic management of the disease.

After the use of different Giemsa staining techniques, variations in chromosome banding patterns have often been observed in animal chromosomes. Such staining differences are usually interpreted to indicate that there is more than one type of heterochromatin in many animal chromosomes. Using two differential Giemsa staining techniques we have found different staining patterns in the chromosomes of two higher plants, Allium cepa and Ornithogalum virens. Furthermore, pericentric heterochromatin that occurs so commonly in animal chromosomes was specifically Giemsa stained in O. virens. These results suggest the basic similarity of higher plant and animal chromosomes.