Assessing the Risk of Various Stocking Strategies in the Semi-Arid Savanna of Kwazulu-Natal, South Africa.

1996 ◽  
Vol 18 (1) ◽  
pp. 136 ◽  
Author(s):  
GP Hatch ◽  
NM Tainton ◽  
GF Ortmann

Rainfall in arid and semi-arid environments is a major determinant of system dynamics which results in seasonal fluctuations in forage production. The influence of fixed and variable stocking strategies on the distributions of forage deficit period and net return for various range condition scenarios were examined using a bioeconomic model. Although the risk of forage deficits and financial losses were reduced with lighter stocking, this was at the opportunity cost of higher returns during wetter seasons. Increased stocking increased returns during wetter seasons, but at the cost of increased risk of forage deficits and highly negative returns during drier seasons. Flexible stocking may combine the benefits of each approach and reduce financial risk. The development of cumulative probability distributions will allow range users to assess the level of risk attached to different strategies. Incorporation of the ecological effects of stocking strategies as feedback into the model would be important to evaluate ecological risk.

2020 ◽  
Vol 29 (1) ◽  
pp. 223-242 ◽  
Author(s):  
Lee Jones ◽  
Vanessa Banks ◽  
Ian Jefferson

AbstractSwelling and shrinking soils are soils that can experience large changes in volume due to changes in water content. This may be due to seasonal changes in moisture content, local site changes such as leakage from water supply pipes or drains, changes to surface drainage and landscaping, or following the planting, removal or severe pruning of trees or hedges. These soils represent a significant hazard to structural engineers across the world due to their shrink–swell behaviour, with the cost of mitigation alone running into several billion pounds annually. These soils usually contain some form of clay mineral, such as smectite or vermiculite, and can be found in humid and arid/semi-arid environments where their expansive nature can cause significant damage to properties and infrastructure. This chapter discusses the properties and costs associated with shrink–swell soils, their formation and distribution throughout the UK and the rest of the world, and their geological and geotechnical characterization. It also considers the mechanisms of shrink-swell soils and their behaviour, reviewing strategies for managing them in an engineering context, before finally outlining the problem of trees and shrink–swell soils.


2013 ◽  
pp. 532-538 ◽  
Author(s):  
Muhammad Kadwa ◽  
Carel N Bezuidenhout

The Eston Sugar Mill is the newest in the South African KwaZulu-Natal sugar belt. Like most other mills, it can be argued that there are inefficiencies in the supply chain due to systematic issues, which reduce optimum performance. It was alleged that mill processes are slowed, or stopped, on Sundays, Mondays, as well as some Tuesdays and Wednesdays, due to pay-weekends, because of the associated cutter absenteeism. This increases the length of the milling season (LOMS), increases milling costs and reduces the average cane quality for the season. Data on cane deliveries to the Eston Mill, over a period of five seasons, were analysed to study the magnitude of the problem. It was statistically verified that cane shortages occur immediately after payweekends and it was conservatively estimated that cutter absenteeism occurs between 25–29 days per season, which increases the LOMS by six to ten days. The associated cost of this problem equated to an average of US$159,500 (approximately EUR120,000) per milling season. In this paper, an alternative harvesting system scenario is suggested, assuming that mechanical harvesters be used after a pay-weekend, to mitigate the impacts of cutter shortages. However, the solution is calculated to be risky. When the cost of new equipment was considered, only two of the five seasons were able to justify the associated costs.


Plants ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 354
Author(s):  
El-Sayed M. Desoky ◽  
Elsayed Mansour ◽  
Mohamed M. A. Ali ◽  
Mohamed A. T. Yasin ◽  
Mohamed I. E. Abdul-Hamid ◽  
...  

The influence of 24-epibrassinolide (EBR24), applied to leaves at a concentration of 5 μM, on plant physio-biochemistry and its reflection on crop water productivity (CWP) and other agronomic traits of six maize hybrids was field-evaluated under semi-arid conditions. Two levels of irrigation water deficiency (IWD) (moderate and severe droughts; 6000 and 3000 m3 water ha−1, respectively) were applied versus a control (well-watering; 9000 m3 water ha−1). IWD reduced the relative water content, membrane stability index, photosynthetic efficiency, stomatal conductance, and rates of transpiration and net photosynthesis. Conversely, antioxidant enzyme activities and osmolyte contents were significantly increased as a result of the increased malondialdehyde content and electrolyte leakage compared to the control. These negative influences of IWD led to a reduction in CWP and grain yield-related traits. However, EBR24 detoxified the IWD stress effects and enhanced all the above-mentioned parameters. The evaluated hybrids varied in drought tolerance; Giza-168 was the best under moderate drought, while Fine-276 was the best under severe drought. Under IWD, certain physiological traits exhibited a highly positive association with yield and yield-contributing traits or CWP. Thus, exogenously using EBR24 for these hybrids could be an effective approach to improve plant and water productivity under reduced available water in semi-arid environments.


Author(s):  
Abdul Rahman Ramdzan ◽  
Mohd Rizal Abdul Manaf ◽  
Azimatun Noor Aizuddin ◽  
Zarina A. Latiff ◽  
Keng Wee Teik ◽  
...  

Colorectal cancer (CRC) remains the second leading cause of cancer-related deaths worldwide. Approximately 3–5% of CRCs are associated with hereditary cancer syndromes. Individuals who harbor germline mutations are at an increased risk of developing early onset CRC, as well as extracolonic tumors. Genetic testing can identify genes that cause these syndromes. Early detection could facilitate the initiation of targeted prevention strategies and surveillance for CRC patients and their families. The aim of this study was to determine the cost-effectiveness of CRC genetic testing. We utilized a cross-sectional design to determine the cost-effectiveness of CRC genetic testing as compared to the usual screening method (iFOBT) from the provider’s perspective. Data on costs and health-related quality of life (HRQoL) of 200 CRC patients from three specialist general hospitals were collected. A mixed-methods approach of activity-based costing, top-down costing, and extracted information from a clinical pathway was used to estimate provider costs. Patients and family members’ HRQoL were measured using the EQ-5D-5L questionnaire. Data from the Malaysian Study on Cancer Survival (MySCan) were used to calculate patient survival. Cost-effectiveness was measured as cost per life-year (LY) and cost per quality-adjusted life-year (QALY). The provider cost for CRC genetic testing was high as compared to that for the current screening method. The current practice for screening is cost-saving as compared to genetic testing. Using a 10-year survival analysis, the estimated number of LYs gained for CRC patients through genetic testing was 0.92 years, and the number of QALYs gained was 1.53 years. The cost per LY gained and cost per QALY gained were calculated. The incremental cost-effectiveness ratio (ICER) showed that genetic testing dominates iFOBT testing. CRC genetic testing is cost-effective and could be considered as routine CRC screening for clinical practice.


1996 ◽  
Vol 47 (6) ◽  
pp. 829 ◽  
Author(s):  
JB Lowry ◽  
CS McSweeney ◽  
B Palmer

Mammalian metabolism of plant phenolics, initially studied in monogastric animals, gave an emphasis to their toxic and antinutrient effects. Subsequent studies in tropical ruminants and wild herbivores have highlighted the high levels than can occur in some diets and the extensive microbial modification and degradation that can occur in the tract. This paper reviews aspects of plant phenolics as they relate to ruminant nutrition in tropical or semi-arid environments in which some forage plants contain high levels of phenolic compounds. Effects range from occasional acute toxicity of hydrolysable tannins, to acetate-releasing microbial degradations that apparently enable certain phenolics to act as nutrients. The most important and complex effects are those due to tannin-protein interactions. Although these can clearly reduce feed intake, nutrient digestibilities, and protein availability, many of the interactions are still not understood. The diverse effects of plant phenolics on nutrient flow probably result from the balance between adverse effects on some organisms and the rate at which they are degraded or inactivated by other organisms, and improved animal performance can likely be obtained by manipulation of rumen microbial metabolism.


2021 ◽  
Vol 283 ◽  
pp. 110051
Author(s):  
Nompumelelo Thelma Mobe ◽  
Sebinasi Dzikiti ◽  
Timothy Dube ◽  
Dominic Mazvimavi ◽  
Zanele Ntshidi

2021 ◽  
pp. 105566562110698
Author(s):  
Kristaninta Bangun ◽  
Jessica Halim ◽  
Vika Tania

Chromosome 17 duplication is correlated with an increased risk of developmental delay, birth defects, and intellectual disability. Here, we reported a female patient with trisomy 17 on the whole short arm with bilateral complete cleft lip and palate (BCLP). This study will review the surgical strategies to reconstruct the protruding premaxillary segment, cleft lip, and palate in trisomy 17p patient. The patient had heterozygous pathogenic duplication of chromosomal region chr17:526-18777088 on almost the entire short arm of chromosome 17. Beside the commonly found features of trisomy 17p, the patient also presented with BCLP with a prominent premaxillary portion. Premaxillary setback surgery was first performed concomitantly with cheiloplasty. The ostectomy was performed posterior to the vomero-premaxillary suture (VPS). The premaxilla was firmly adhered to the lateral segment and the viability of philtral flap was not compromised. Two-flap palatoplasty with modified intravelar veloplasty (IVV) was performed 4 months after. Successful positioning of the premaxilla segment, satisfactory lip aesthetics, and vital palatal flap was obtained from premaxillary setback, primary cheiloplasty, and subsequent palatoplasty in our trisomy 17p patient presenting with BLCP. Postoperative premaxillary stability and patency of the philtral and palatal flap were achieved. Longer follow-up is needed to evaluate the long-term effects of our surgical techniques on inhibition of midfacial growth. However, the benefits that the patient received from the surgery in improving feeding capacity and facial appearance early in life outweigh the cost of possible maxillary retrusion.


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