Environmental challenges to operationalisation of South African rainfall enhancement

Most of the atmospheric moisture in systems moving across South Africa leaves the sub-continent as the weather systems move out over the ocean, only a tenth of it falls on the landmass as rain. An increase in the efficiency of the atmospheric moisture delivery system by means of rainfall enhancement is therefore an attractive concept. Rainfall enhancement functions by either providing additional Cloud Condensation Nuclei or Ice forming Nuclei that will beneficially influence the precipitation formation process, improving the efficiency of moisture to rainfall conversion. Systematic South African research into rainfall enhancement started in the 1970s. The South African Rainfall Enhancement Programme (SAREP), initiated in the late 1990\'s, is the most recent in a series of studies and was the first semi-operational rainfall enhancement project to occur in South Africa as a response to drought conditions. In a recent study (DWAF, 2004 in prep) to finalise SAREP and provide guidance on operationalising rainfall enhancement, it was recommended that environmental impact assessment must be undertaken before this technology is implemented further. Rainfall enhancement falls specifically within the jurisdiction of the National Water Act (NWA) and the National Environmental Management Act (NEMA). A licence to undertake rainfall enhancement activities is required from the Minister of Water Affairs and Forestry after an appropriate environmental impact assessment has been undertaken to inform his decision. This paper proposes an approach to fulfil the legal requirements for operationalising future rainfall enhancement. The interaction between the science of rainfall enhancement and the ability of scientific disciplines to determine relevant environmental impacts, to appropriately inform the decision-making process, is specifically highlighted. The data requirements identified by scientists during the study varies in duration and resource needs and does not differentiate between ongoing scientific research and the requisite information required for informed decision making. This paper contemplates an approach which provides for holistic and co-ordinated investigation of South African rainfall enhancement into the future. Water SA Vol. 30 (5) 2005: pp.88-9

Technique of anterior colporrhaphy: a Dutch evaluation

Contains fulltext : 96395.pdf (publisher's version ) (Closed access)INTRODUCTION AND HYPOTHESIS: To evaluate the variation in techniques of anterior colporrhaphy among members of the Dutch Urogynecologic Society. METHODS: A questionnaire evaluating the technique of anterior colporrhaphy, preoperative and postoperative care, and use of the POP-Q score was sent out by e-mail. RESULTS: One hundred thirty-three completed questionnaires were received. The response rate was 65%. There are large variations in incisions, use of hydrodissection, method of plication, and excision of redundant vaginal epithelium. The urinary catheter was generally removed on day 2 after surgery and the vaginal pack on day 1. Less than half of the respondents used the POP-Q score routinely. CONCLUSIONS: Dutch gynecologists use a variety of surgical techniques to operate on a cystocele. This suggests that there is no widely accepted opinion on the best surgical approach. The lack of differentiation between central and lateral defects is striking and in contrast with the, mostly, American literature

Leisure, Popular Culture and Memory: The Invention of Dark Age Britain, Wales, England, and Middle-earth in the songs of Led Zeppelin

In the period of high modernity, and in the process of establishing the imperial nation-state of Great Britain, historians, archaeologists and enthusiastic amateurs searched high and low for material evidence and primary sources from what was called the Dark Ages. There is a gap in knowledge about this past, and all discussion rests on finding meaning in fading inscriptions, or dark earth, or trusting completely the writings of Bede and Gildas. The search for an identity and history for the nation for Great Britain was based on nationalist beliefs about Englishness, Britishness or Welshness. In the twentieth-century, the problem of Englishness, place and myth led Tolkien to write his Middle-earth stories in his leisure time. At the same time, the problem of Welshness or Britishness saw a growth in interest – in film and books - in Arthurian traditions, and a tourist interest in the Celtic fringe of Britain. In this paper, I show how the songs and album covers of Led Zeppelin, and their film The Song Remains the Same, draw upon both the work of Tolkien and the Arthurian traditions to construct ideas of masculine belonging in some mythological medieval time and place. While this constriction is idiosyncratic to the artists, they are drawing on and justifying the wider problem of England, Wales and Britain in leisure and culture

Mapping the Paediatric Quality of Life Inventory (PedsQL™) Generic Core Scales onto the Child Health Utility Index–9 Dimension (CHU-9D) Score for Economic Evaluation in Children

Background: The Paediatric Quality of Life Inventory (PedsQL™) questionnaire is a widely used, generic instrument designed for measuring health-related quality of life (HRQoL); however, it is not preference-based and therefore not suitable for cost–utility analysis. The Child Health Utility Index–9 Dimension (CHU-9D), however, is a preference-based instrument that has been primarily developed to support cost–utility analysis. Objective: This paper presents a method for estimating CHU-9D index scores from responses to the PedsQL™ using data from a randomised controlled trial of prednisolone therapy for treatment of childhood corticosteroid-sensitive nephrotic syndrome. Methods: HRQoL data were collected from children at randomisation, week 16, and months 12, 18, 24, 36 and 48. Observations on children aged 5 years and older were pooled across all data collection timepoints and were then randomised into an estimation (n = 279) and validation (n = 284) sample. A number of models were developed using the estimation data before internal validation. The best model was chosen using multi-stage selection criteria. Results: Most of the models developed accurately predicted the CHU-9D mean index score. The best performing model was a generalised linear model (mean absolute error = 0.0408; mean square error = 0.0035). The proportion of index scores deviating from the observed scores by 13 years) or patient groups with particularly poor quality of life. ISRCTN Registry No: 1664524

EBG Placement Optimization in a Via-Fed Stacked Patch Antenna for Full-Duplex Wireless

Full-Duplex (FD) wireless communication has the potential to double the capacity of a wireless link. The key challenge to FD is self-interference (SI): a node’s transmitting signal generates significant interference to its own receiver. Several prior works have shown the potential to reduce SI and build FD radios but they are limited to Sub-6 GHz systems. In this paper, we focus on the emerging mmWave systems and the potential reduction in SI through antenna design. The increased bandwidth requirements of mmWave systems necessitate the use of higher bandwidth antenna designs such as stacked patch antennas for transmission (Tx) and reception (Rx). Specifically, we investigate the optimal placement of a mushroom electromagnetic band gap (EBG) structure for maximum Tx and Rx isolation (coupling reduction) in a 4-layer substrate stacked patch antenna design targeted for small mobile devices. Through extensive simulations we show that top&inner layer EBG ( stacked ) provides more than 80 dB of isolation at 28 GHz frequency, which is 20 dB more isolation than either top or inner layer EBG. We also show that the frequency bandwidth and gain of the stacked patch antenna are not negatively impacted due to the EBG integration

Design of chemical reactors : final report

http://deepblue.lib.umich.edu/bitstream/2027.42/4628/5/bab7779.0001.001.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/4628/4/bab7779.0001.001.tx