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• Four Mallomonas and one Synura species were found in the Mooi River, South Africa. • Cell morphology, dimensions and photographs of each species are presented. • The taxonomy, ecology and geographical distribution of each species are discussed. • Two Mallomonas species are reported for the first time in Africa. • Three Mallomonas and one Synura species are reported for the first time in South. • Africa Four species of the genus Mallomonas (M. alpina, M. annulata, M. caudata , and M. cratis), a unicellular silica-scaled chrysophyte, and one species of Synura (S. curtispina), a colonial silica-scaled chrysophyte, were found in the Mooi River, North West Province, South Africa. Entire Mallomonas cells, having intact scales and bristles, were photographed with the scanning electron microscope, enabling accurate species identification. Cells of Synura curtispina, with distinct scales on the surface, was also found. Short descriptions and dimensions of each species are given, and their known geographical distribution and ecological preferences are discussed. Two species (M. annulata and M. cratis) represent first distribution records for Africa, and four species represent first records for South Africa. Only one species (M. alpina) was previously recorded in South Africa. [ABSTRACT FROM AUTHOR]

Several studies suggested that the sandstones of the Main Karoo Basin of South Africa are potential host rock for hydrocarbon exploration in the Main Karoo Basin of South Africa. However, there is still a paucity of knowledge on the effect of diagenesis on the sandstones and diagenesis is one of the most critical processes influencing reservoir rock properties. As a result, this study investigated the effects of diagenesis on the sandstones by subjecting the sandstone to petrographic studies, scanning electron microscope (SEM), energy dispersive x-ray (EDX) and x-ray diffraction analyses. The petrographic studies show that the sandstones of the Ecca Group mainly comprise of feldspar, quartz and lithic fragments, while garnet, hematite and zircon occur in traces. The sandstones have a matrix content greater than 15% but less than 75% and were classified to be graywacke. The SEM and EDX examinations revealed that the diagenetic processes that have significantly affected the sandstones are compaction, cementation, dissolution, replacement and recrystallization. The dominant types of cement in the sandstones are quartz, calcite, and clay cement. Compaction (i.e., concave-convex contact, suture contact) and cementation (i.e., quartz, calcite, and clay) were the main diagenetic processes responsible for the reduction in porosity while dissolution of feldspars and grain fracturing increased porosity. However, the interconnectivity of the pores in the sandstones are low. Porosity is generally well reduced thus making the quality of the reservoir poor. [ABSTRACT FROM AUTHOR]

It has been suggested that parasites are effective bioindicators as they are sensitive to environmental changes and, in some cases, accumulate trace elements in higher concentrations than their hosts. Accumulated elements sequester in different organs. In monogenean and crustacean ectoparasites, sclerotised structures and egg yolk appear to be the preferred site for element sequestration. In this study, the sequestration of trace elements; Mg, Al, Ca, Fe, Cu, and Zn in Lamproglena clariae was studied from two rivers. Adult L. clariae were collected from the gills of Clarias gariepinus from Lake Heritage in the Crocodile River and in the Vaal River below the Vaal Dam, South Africa. Collected parasites were flash frozen in liquid nitrogen and sectioned with a cryomicrotome. Sections were treated with Phen-Green to observe fluorescent signals. Trace elements in the parasite were analysed using a scanning electron microscope with an energy-dispersive spectroscope (SEM–EDS). Results showed more intense fluorescence signals in the exoskeleton compared to tissues, and in the egg yolk. Analysis by SEM–EDS confirmed the presence of elements in the parasite from both sites. Levels of Al were higher in L. clariae from the Vaal River than those from Lake Heritage, and Fe was higher in L. clariae from Lake Heritage. Element distribution patterns in the parasite matched those in the water from the sites. Unlike other crustaceans, regulation of metals in adult females of L. clariae does not occur through moulting, but high levels occurred in the yolk. [ABSTRACT FROM AUTHOR]

Summary: Stegelletina salinaria is redescribed from Spain and South Africa. Spanish material was collected in sandy soil from the type locality and a nearby area, while one population collected in compost was examined from South Africa. The species is characterised by its small size (0.27-0.41 mm), lateral field with three incisures, lip region with three pairs of dentate lips bearing four tines each, primary axils bearing a large guarding process, secondary axils lacking guarding processes, nerve ring and secretory-excretory pore at isthmus level, spermatheca and post-vulval uterine sac poorly developed, female tail conoid with rounded hyaline terminus and males unknown. The description, light micrographs and scanning electron microscope images, illustrations and molecular analyses are provided. 18S and 28S rDNA sequence analyses show that the isolates of S. salinaria from Spain and South Africa are closely related to each other and to other species of Stegelletina , while also indicating a close relationship with some species of Nothacrobeles , Scottnema and Stegelleta (28S tree) and Zeldia (18S tree). [ABSTRACT FROM AUTHOR]

• Mallomonas corymbosa, M. kenyana and M. porte-ferreae were found in the Vaal River, South Africa. • Cell morphology and geographical distribution of each species are presented. • Water quality of the Vaal river at the time of sampling is presented. • The finding of M. corymbosa represents the first record of this species in Africa. • M. kenyana, a tropical/subtropical species, were found in temperate regions in South Africa. This paper reports on the presence of three Mallomonas species (Phylum Ochrophyta) in the Vaal River, South Africa. Scanning electron microscope observations of entire cells with intact scales and bristles allowed accurate identifications of M. corymbosa, M. kenyana and M. portae-ferreae. Descriptions and dimensions of each of the three species are given, their geographical distribution is discussed and physico-chemistry of the water at the time of their finding is presented. M. corymbosa was recorded for the first time in Africa, expanding its known geographical distribution to an additional continent. The climatic preferences of the tropical and subtropical species, M. kenyana were extended to temperate regions in South Africa. These species were present under eutrophic to hypertrophic conditions, a water temperature of 25.4 °C, neutral to slightly alkaline water (pH 7.25) and a conductivity value of 440 µS/cm. [ABSTRACT FROM AUTHOR]

Introduction: The knowledge of polychaetes in the subtropical region of Africa benefited from the activity of J. Day. However, 50 years after the publication of his Monograph of the Polychaeta of southern Africa, it is necessary to reconsider the identity of the Cirratulidae due to changes in the diagnostic characters and new approaches to the taxonomy of the group to corroborate the status of cosmopolitan species in this region. Objective: We hypothesize that biodiversity of multitentacular Cirratulidae polychaetes has been significantly underestimated in southern Africa. Methods: The present work analyzes material deposited in the Iziko museum, as well as recently collected specimens, using scanning electron microscope to identify them. Results: The material corresponds to two new species belonging to the genus Protocirrineris. Protocirrineris strandloperarum sp. nov. is characterized by having the tentacular filaments between the chaetigers 5 to 10-12 and the first pair of branchiae from chaetiger 7, and P. magalhaesi sp. nov. is characterized by having tentacular filaments between chaetigers 4-8 and the first pair of branchiae from chaetigers 2 or 3. Descriptions of these species, with light and scanning electron microscope images, are given. Schematic drawings of the two new species are shown comparatively with diagnostic characters. Conclusions: The use of new techniques enables discovery of new taxonomic characters and two new species of the genus. The diversity of Cirratulidae polychaetes is underestimated also in the subtropical and tropical regions of Africa. [ABSTRACT FROM AUTHOR]

Archaeomalacological analysis is generally undertaken on recovered macro-remains to characterize the overall composition of faunal remains in a deposit. Given the susceptibility of shell middens to a variety of taphonomic processes, it is assumed that the prior presence of shell in deposits may therefore occasionally be missed. Deteriorated micro-remains can mix indistinguishably into surrounding sediments and make their analyses and identification difficult, particularly in older deposits and in environments that experience rapid rates of weathering. This paper explores whether microscopic remains of deteriorated molluscs can be distinguished from other microscopic remains at the coastal rock shelter site of Waterfall Bluff in Mpondoland, South Africa. The methodology uses a multi-scalar approach integrating shell mineralogy and microstructure using the taxonomic distinctiveness of these features. The diagnostic features (e.g., morphology, hinges, spires, and apertures) used for identifying macro-remains are absent in micro-remains, therefore unique methods of identification are needed to identify these microscopic mollusc fragments. Through mineralogical analyses and scanning electron microscope (SEM) imaging, the nacreous remains of Mytilidae shell were identified from previously unidentified degraded shell remains as well as sediment samples from Waterfall Bluff. These methods thus recovered 'invisible' evidence of shellfish remains providing further evidence of continued coastal foraging from Marine Isotope Stage 3 to the early Holocene (ca or ⁓ 40 ka to 10 ka) on the south-eastern African coast. • Multi-scalar approach integrating shell mineralogy and microstructure to taxonomically identify micro-shell remains. • Highly fragmented and degraded shell remains at WB due to acid dissolution from drip water under the dripline. • Nacre tablets identified by Scanning Electron Microscopy in an aggregate with no macro shell evidence. • Ostreidae and Mytilidae mollusc shell microstructure and composition examined. [ABSTRACT FROM AUTHOR]

Pin nematodes of the genus Paratylenchus are widely distributed across the world and associated with many plant species. Morphological identification of Paratylenchus species is a difficult task because it relies on many characters with a wide range of intraspecific variation. In this study we provide morphological and molecular characterisation of several pin nematodes: Paratylenchus aquaticus, P. dianthus, P. hamatus, P. nanus and P. straeleni, collected in different states of the USA and South Africa. Paratylenchus aquaticus is reported from South Africa and Hawaii and P. nanus is found from South Africa for the first time. Morphological descriptions, morphometries, light and scanning electron microscopic photos and drawings are given for these species. Molecular characterisation of nematodes using the D2-D3 of 28S rRNA and ITS rRNA gene sequence revealed that samples morphologically identified as P. aquaticus, P. hamatus and P. nanus indeed represent species complexes containing several species. Sequences of the rRNA genes are also provided for several unidentified Paratylenchus. Phylogenetic relationships within the genus Paratylenchus are given as inferred from the analyses of the D2-D3 of 28S rRNA and ITS rRNA gene sequences. We present here the most complete phylogenetic analysis of the genus. [ABSTRACT FROM AUTHOR]

Abstract: This research focuses on scale pattern and cross sectional morphology of hair to identify an expanded sample of fossil hairs from Parahyaena brunnea coprolites from Gladysvale cave in the Sterkfontein Valley, South Africa. The coprolites are part of a brown hyaena latrine preserved in calcified cave sediment dated to the Middle Pleistocene (257–195 ka). Forty-eight fossil hairs were extracted from 12 coprolites using fine tweezers and a binocular microscope, and examined using a scanning electron microscope. Hair identification was based on consultation of standard guides to hair identification and comparison with our own collection of samples of guard hairs from 15 previously undocumented taxa of indigenous southern African mammals. Samples were taken from the back of pelts curated at the Johannesburg Zoo and Ditsong National Museum of Natural History (formerly Transvaal Museum, Pretoria). Based on the fossil hairs identified here, this research has established that brown hyaenas shared the Sterkfontein Valley with hominins, warthog, impala, zebra and kudu. Apart from humans, these animals are associated with savanna grasslands, much like the Highveld environment of today. These findings support the previous tentative identification of fossil human hair in the coprolites, provide a new source of information on the local Middle Pleistocene fossil mammal community, and insight into the environment in which archaic and emerging modern humans in the interior of the African subcontinent lived. [Copyright &y& Elsevier]

In this study, mass concentrations and physico-chemical characteristics of suspended particulates of aerodynamic size 10 μm (PM10) were evaluated. A dual E-Sampler which combines the light scatter and the gravimetric filter methods was used. Sampling occurred between August and December 2009. Scanning Electron Microscope – Energy Dispersive Spectrometry (SEM-EDS) and Inductively Coupled Plasma 6000 were used for elemental and physical characterization. The highest daily average mass concentration measured was 0.03543 mg/m3 and was below the international and national daily limit of 0.150 mg/m3, as well as the strict Vaal Triangle regional standard of 0.075 μg/m3. Relatively high daily average mass concentrations were obtained during the winter period. Concentrations of evaluated heavy metals decreased in the following order: iron (Fe) > manganese (Mn) > zinc (Zn) > copper (Cu) > vanadium (V) > titanium (Ti) > nickel (Ni) > lead (Pb). Positive correlations were established between Zn and Pb (r = 0.916); Zn and Mn (r = 0.883); Zn and V (0.984); Zn and Ni (r = 0.877); Zn and Fe (r = 0.914), which suggests common sources. However, Zn and Ti (r = 0.522); Zn and Cu (0.781) were poorly correlated. [ABSTRACT FROM AUTHOR]

Ornithogalum beyazoglui Y.Bagci, Savran & O. D. Düsen sp. nov. (Hyacinthaceae), a new species is described and illustrated from Izmir, Ödemis, Bozdag (Izmir, Ödemis province). Diagnostic morphological characters are discussed, including SEM examination of seed coat surface. Data are also presented on ecology, biogeography and conservation status of the new species. [ABSTRACT FROM AUTHOR]

Abstract: Quantitative automated mineralogy is the acquisition of mineralogical and textural data by scanning electron microscopy-based energy dispersive analytical methods. The technique is used in the metals and energy resource extraction industries to provide accurate mineral characterization information over large data sets. We have employed this method to three projects related to diamonds: mantle peridotite, kimberlite, and garnet concentrate. The first example assesses the metasomatic clinopyroxene-phlogopite modal mineralogy in peridotite xenoliths from Premier/Cullinan (South Africa). Understanding mantle mineral variability can be coupled with measureable mineral properties to develop mantle geophysical and geochemical models. The second example compares kimberlites from Letšeng Satellite Pipe (Lesotho) and Ngamiland (Botswana), to assess the variability of kimberlite mineralogy. Kimberlite domains can be identified on a micro scale with potential to understand parameters such as hardness and grindability, or to identify kimberlite clusters with discrete mineral assemblages. The third example applies mineral compositional variability in garnet concentrate samples as a possible tool for evaluating exploration projects. Application of garnet definitions to concentrates through digitally grouping grains into discrete populations results in improved understanding of large sample populations and hence diamond prospectivity. Quantitative mineralogy applied to diamond-related projects utilizes the principles of geometallurgy in evaluating large data sets for greater understanding of the variability of mantle materials. [Copyright &y& Elsevier]

Foot-and-mouth disease virus serotype South-Africa territories-2 (FMDV-SAT-2) is the most fastidious known type in Aphthovirus which is subsequently reflected in the diagnosis regime. Rapid and early diagnostic actions are usually taken in response to the FMDV outbreak to prevent the dramatic spread of the disease. Virus imprinted sensor (VIP sensor) is gathering huge attention for the selective detection of pathogens. Thus, the whole virus particles of SAT-2 together with an electropolymerized film of poly(o-phenylenediamine) (PoPD) on gold-copper modified screen-printed electrode were applied to fabricate SAT-2-virus imprinted polymer (SAT-2-VIP). The SAT-2-VIPs were fully characterized using cyclic voltammetry (CV), linear sweep voltammetry (LSV), Atomic force microscopy (AFM), Scanning electron microscope (SEM), and Fourier transform Infra-Red (FTIR) spectroscopy. Excellent selective binding affinity towards the targeted virus particle was achieved with limits of detection and quantification of 0.1 ng/mL and 0.4 ng/mL, respectively. In terms of viral interference, the sensor did not show cross-reactivity towards other animal viruses including FMDV serotype A, O, or even SAT-2 subtype Libya and the un-related virus Lumpy skin disease virus (LSDV). This high selectivity provides a sensible platform with 70 folds more sensitivit y than the reference RT-PCR as revealed from the application of SAT-2-VIP sensor for rapid analysis of clinical samples with no need for treatment or equipped labs. Thus, as diagnostic and surveillance technologies, on-site point of care diagnostics for SAT-2 virus are supported. [Display omitted] • Electrochemical method for FMDV-SAT2 detection was achieved. • Electrochemical imprinting of the whole virus particles on the nanostructured electrodes was optimized. • The SAT2-VIP sensor is simple to fabricate, easy to operate and shows high performance in clinical diagnosis. [ABSTRACT FROM AUTHOR]

Airborne measurements were conducted in the winter months of July and August 2003 over the metropolitan area of Cape Town to characterize physical, chemical and optical properties of aerosol particles during intense brown haze episodes. Particles were collected on highly temporally and spatially resolved samples and investigated using a high-resolution scanning electron microscope (SEM). From morphology and elemental composition, particles were categorized in terms of seven groups: aggregated soot particles, mineral dust, sulphates (SO42-), sea-salt, tar balls/fly ash, rod-shaped particles associated with soot agglomerates, and those that could not be attributed to any of these groups. Refractive indices of aerosols were derived from chemical distributions obtained from SEM analysis and combined with in situ measurements of number-size distributions to determine optical properties of dry particles in the size range 0.1-3.5 μm. Particles exhibited marked spatial and temporal variability in chemical composition. They were externally mixed with highly absorbing soot particles. From number concentrations, light extinction and absorption coefficient ranges were σep = 19-755 Mm-1 and σap = 7-103 Mm-1, respectively (at wavelength λ = 550 nm). Single scattering albedo, ω0, varied from 0.61 to 0.87 with a mean value of 0.72 ± 0.08; this value was much lower than generally reported in the literature, a result that was attributed to high concentrations of highly absorbing soot (fractional number concentrations of up to 46% were observed in the SEM). The haze could be attributed to extinction of light by fine aerosols composed mainly of anthropogenic particles. High extinction coefficients and low single scattering albedo computed here demonstrate quantitatively the contributions of particulate matter to visibility reduction and the brown haze phenomenon in Cape Town. [ABSTRACT FROM AUTHOR]

Residential coal combustion is one of the most significant sources of carbonaceous aerosols in the Highveld region of South Africa, significantly affecting the local and regional climate. This study investigated single coal-burning particles emitted when using different fire-ignition techniques (top-lit up-draft versus bottom-lit up-draft) and air ventilation rates (defined by the number of air holes above and below the fire grate) in selected informal braziers. Aerosol samples were collected on nucleopore filters at the Sustainable Energy Technology and Research Centre Laboratory, University of Johannesburg. The individual particles (~700) were investigated using a scanning electron microscope equipped with energy-dispersive X-ray spectroscopy (EDX). Two distinct forms of spherical organic particles (SOPs) were identified, one less oxidized than the other. The particles were further classified into electronically dark and bright. The EDX analysis showed that 70% of the dark spherical organic particles had higher (~60%) relative oxygen content than in the bright SOPs. The morphology of spherical organic particles were quantified and classified into four categories: ~50% were bare single particles; ~35% particles were aggregated and formed diffusion accretion chains; 10% had inclusions, and 5% were deformed due to impaction on filter material during sampling. This study concludes that there are two distinct kinds of coal burning spherical organic particles and that dark SOPs are less volatile than bright SOPs. The authors also show that these spherical organic particles are similar in nature and characteristics to tar balls observed in biomass combustion and that they have the potential to absorb sunlight thereby affecting the earth's radiative budget and climate. This study provides insights into the mixing states, morphology, and possible formation mechanisms of these organic particles from residential coal combustion in informal stoves. [ABSTRACT FROM AUTHOR]

A technique for the preparation of heteroderid cysts for scanning electron microscopy of internal structures are discussed. The results were good enough for publication and the process relatively fast. [ABSTRACT FROM AUTHOR]