Design of Non-Uniformly Excited Linear Slot Arrays Fed by Coplanar Waveguide

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Investigation into the metal contamination of the Plankenburg and Diep Rivers, Western Cape, South Africa

Metal contamination in the Plankenburg and Diep Rivers (Western Cape) was investigated over a 12 and 9 month period, respectively. Aluminium (Al), copper (Cu), iron (Fe), lead (Pb), manganese (Mn), nickel (Ni) and zinc (Zn) concentrations were determined using the nitric acid digestion method and analysed by inductively coupled plasma atomic emission spectrometry (ICP-AES). For both rivers the Al and Fe concentrations were higher than that for all the other metals analysed for in sediment and water samples. The highest concentrations recorded in the Plankenburg River were 13.6 mgE.-1 (water . Week 18, Site B) and 15 018 mgEkg-1 (sediment . Week 1, Site C) for Al, and 48 mgE.-1 (water . Week 43, Site A) and 14 363.8 mgEkg-1 (sediment . Week 1, Site A) for Fe. The highest concentrations recorded in the Diep River were 4 mgE.-1 (water . Week 1, Site A) and 19 179 mgEkg-1 (sediment . Week 1, Site C) for Al, and 513 mgE.-1 (water . Week 27, Site A) and 106 379.5 mgEkg-1 (sediment . Week 9, Site C) for Fe. For most of the metals analysed the concentrations were higher than the recommended water quality guidelines as stipulated by the Department of Water Affairs and Forestry, the Canadian Council for the Ministers of the Environment and the accepted eworld averagef. Point sources of pollution could not be conclusively identified, but runoff from both industrial and residential areas could have contributed to the increased concentrations. Metal concentrations should be routinely monitored and the guidelines should be updated and revised based on the current state of the rivers and pollution sources

Variation in levels and removal efficiency of heavy and trace metals from wastewater treatment plant effluents in Cape Town and Stellenbosch, South Africa

This study focused on one year monitoring campaign to monitor the occurrence and removal of Endocrine Disruptive Metals (EDMs) and trace metals from selected wastewater treatment plants (WWTPs) in Stellenbosch and Cape Town. Composite water samples were collected from the WWTPs from January 2010 to December 2010 on a quarterly basis and concentrations determined using inductively coupled plasma-mass spectrometry (ICP-MS) after open beaker digestion. A total of 432 water samples consisting of raw, primary effluent, secondary effluent and final effluents were collected and analyzed. The general abundance distribution pattern for metals was Zn > Cu > Pb > Cr > Ni > As > Co > Cd > Hg. The removal efficiency ranged from 1.5% for Hg at Zandvliet WWTP plant during winter to 98.27% for Cu at Athlone WWTP treatment plant during summer. The final effluent concentration for most of the metals were within South African water quality guidelines while As, Hg, Cd and Pb concentration were higher than maximum limits set by the Canadian Council of Ministers of the Environment. Potsdam WWTP showed to be the most effective at heavy metals removal as compared with the other five treatment plants investigated in this study. The effluent metal concentration over time could pose health risk if used for agricultural irrigation.Keywords: Seasonal variation, endocrine disrupting metals, wastewater treatment plants, effluents, coupled plasma-mass spectrometry (ICP-MS), Cape Tow

Identification of metal-tolerant organisms isolated from the Plankenburg River, Western Cape, South Africa

The ability of biofilms to resist pollutants makes them advantageous for use in bioremediation. The objective of this investigation was to isolate metal-tolerant micro-organisms from a site along the Plankenburg River. Microbial biofilms cultivated in multi-channelled flow cells were exposed to varying concentrations of aluminium (Al), iron (Fe), copper (Cu), manganese (Mn), nickel (Ni) and zinc (Zn), stained with the BacLightTM viability probe, visualised using epifluorescence microscopy and analysed using ScionImage. Exposure to the highest Al, Fe, Cu and Mn concentrations increased the percentages of dead cells. A difference in live and dead cells after exposure to varying Zn and Ni concentrations was not evident. When exposed to the lowest concentrations, no notable difference could be detected in comparison with the untreated control. Possible metal-tolerant micro-organisms were identified from the exposed flow cells using polymerase chain reaction (PCR) and deoxyribonucleic acid (DNA) sequencing, followed by ClustalX alignment and phylogenetic analysis. Phylogenetic analysis identified a variety of organisms, including Bacillus sp., Pseudomonas sp., Delftia tsuruhatensis strain A90, Kocuria kristinae strain 6J-5b, Comamonas testosteroni WDL7, Stenotrophomonas maltophilia strain 776, Staphylococcus sp. MOLA:313, Micrococcus sp. TPR14, Sphingomonas sp. 8b-1 and Microbacterium sp. PAO-12. Two major clusters could be distinguished based on their Gram-reactions.Keywords: BacLightTM viability probe, biofilms, phylogenetic analysis, river water, ScionImag

Investigation into metal contamination of the Berg River, Western Cape, South Africa

A recent decline in water quality of the Berg River, Western Cape, South Africa, has led to the investigation into the degree of metal pollution in the river system. This study was conducted over a period of one year, from May 2004 to May 2005. The nitric acid digestion technique was used to extract metals from water, sediment and biofilm samples collected at various points (Site A . agricultural area, Site B . informal settlement and Site C . Newton pumping station) along the Berg River. Metal concentrations were determined using inductively coupled plasma atomic emission spectrometry (ICP-AES). The highest mean metal concentrations recorded were as follows; water samples, 6 mgE.-1 for Al, 14.6 mgE.-1 for Fe and 18.8 mg..-1 for Mn; sediment samples, 17 448.8 mgEkg-1 for Al and 26 473.3 mgEkg-1 for Fe; biofilm samples, 876.8 mgE.-1 for Al and 1 017.5 mgE.-1 for Fe. The increased availability, or noteworthy incidence of Al and Fe, could be due to the leaching of metals into the river water from waste and household products associated with the informal settlement and the subsequent settling on sediment. No guidelines were available for metals in biofilms. The highest recorded concentrations in water were for Site C (agricultural area). Recorded concentrations in water fluctuated throughout the study period for most of the metals analysed, but Al and Fe were consistently above the recommended guidelines as stipulated by the Department of Water Affairs and Forestry and the Canadian Council of Ministers of the Environment

Construction and validation of the Touch Experiences and Attitudes Questionnaire (TEAQ): a self-report measure to determine attitudes to and experiences of positive touch

Despite growing interest in the beneficial effects of positive touch experiences throughout our lives, and individual differences in how these experiences are perceived, a contemporary self-report measure of touch experiences and attitudes for which the factor structure has been validated, is as yet not available. This article describes four studies carried out during the construction and validation of the Touch Experiences and Attitudes Questionnaire (TEAQ). The original TEAQ, containing 117 items relating to positive touch experiences was systematically constructed. Principal component analysis reduced this measure to 57 items and identified six components relating to touch experiences during childhood (ChT) and adult experiences relating to current intimate touch (CIT) and touch with friends and family (FFT). Three attitudinal components were identified, relating to attitude to intimate touch (AIT), touch with unfamiliar people (AUT) and self-care (ASC). The structure of this questionnaire was confirmed through confirmatory factor analysis carried out on data obtained from a second sample. Good concurrent and predictive validity of the TEAQ compared to other physical touch measures currently available was identified. Known-group validity in terms of gender, marital status and age was determined, with expected group differences identified. This study demonstrates the TEAQ to have good face validity, internal consistency, construct validity in terms of discriminant validity, known-group validity and convergent validity, and criterion-related validity in terms of predictive validity and concurrent validity. We anticipate this questionnaire will be a valuable tool for the field of physical touch research

A core outcome set for pre‐eclampsia research: an international consensus development study

Objective To develop a core outcome set for pre‐eclampsia. Design Consensus development study. Setting International. Population Two hundred and eight‐one healthcare professionals, 41 researchers and 110 patients, representing 56 countries, participated. Methods Modified Delphi method and Modified Nominal Group Technique. Results A long‐list of 116 potential core outcomes was developed by combining the outcomes reported in 79 pre‐eclampsia trials with those derived from thematic analysis of 30 in‐depth interviews of women with lived experience of pre‐eclampsia. Forty‐seven consensus outcomes were identified from the Delphi process following which 14 maternal and eight offspring core outcomes were agreed at the consensus development meeting. Maternal core outcomes: death, eclampsia, stroke, cortical blindness, retinal detachment, pulmonary oedema, acute kidney injury, liver haematoma or rupture, abruption, postpartum haemorrhage, raised liver enzymes, low platelets, admission to intensive care required, and intubation and ventilation. Offspring core outcomes: stillbirth, gestational age at delivery, birthweight, small‐for‐gestational‐age, neonatal mortality, seizures, admission to neonatal unit required and respiratory support. Conclusions The core outcome set for pre‐eclampsia should underpin future randomised trials and systematic reviews. Such implementation should ensure that future research holds the necessary reach and relevance to inform clinical practice, enhance women's care and improve the outcomes of pregnant women and their babies

Identification of Point Sources of Metal Pollution in the Berg River, Western Cape, South Africa

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Reproduction of Cubaris murina (Crustacea: Isopoda) under laboratory conditions and its use in ecotoxicity tests

Reproduction of the isopod Cubaris murina was studied in the laboratory in order to observe the offspring number per brood, the number and duration of the incubation periods, and the influence of repeated mating on number of young per brood. An experiment was conducted with two different groups: female/male pairs and females that were isolated after mating. No significant difference was found between the two reproductive female groups for the mean number of young per brood (x = 25) and the duration of the incubation periods (x = 17 days). One mating was enough for at least five broods, with no reduction in brood size. There was no significant difference between the number of adult males and females. Low-density cultures had a significantly higher growth rate compared to high-density cultures. Furthermore, the experimental results for optimization isopod culture conditions for terrestrial ecotoxicity testing are reported