An Improved Systems Approach as a Phytosanitary Measure for Thaumatotibia leucotreta (Lepidoptera: Tortricidae) in Export Citrus Fruit From South Africa

2020 ◽  
Vol 113 (2) ◽  
pp. 700-711 ◽  
Author(s):  
Vaughan Hattingh ◽  
Sean Moore ◽  
Wayne Kirkman ◽  
Mat Goddard ◽  
Sean Thackeray ◽  
...  
Keyword(s):  
South Africa ◽  
Systems Approach ◽  
Risk Mitigation ◽  
A Priori ◽  
Citrus Fruit ◽  
Sampling Inspection ◽  
Valencia Orange ◽  
Phytosanitary Measure ◽  
Thaumatotibia Leucotreta ◽  
Parameter Values

Abstract A systems approach was previously developed for mitigating phytosanitary risk of Thaumatotibia leucotreta (Meyrick) in citrus fruit exported from South Africa, as an alternative to a standalone cold disinfestation treatment. The present study first tested the original systems approach by applying it on a semicommercial scale in 10 Nova mandarin orchards. Fruit were inspected at points in the production, packing, and simulated shipping process, to assess performance of the systems approach. Additional data were obtained from 17 Valencia orange orchards and six packinghouses. In the second part of this study, the systems approach was accordingly revised and improved, consisting of three measures: 1) preharvest controls and measurements and postpicking sampling, inspection, and packinghouse procedures; 2) postpacking sampling and inspection; and 3) shipping conditions. The model quantifying the effectiveness of the systems approach was improved by correcting errors in the original version, updating parameter values and adding a component that provides for comparison with the risk mitigation provided by a standalone disinfestation treatment. Consequently, the maximum potential proportion of fruit that may be infested with live T. leucotreta after application of the improved systems approach is no greater than the proportion of fruit that may be infested after application of a Probit 9 efficacy postharvest disinfestation treatment to fruit with a 2% pretreatment infestation. The probability of a mating pair surviving is also determined. The model enables a priori determination of the required threshold levels for any of the three measures, based on quantification of the other two measures.

scholarly journals Commodity risk assessment of Citrus L. fruits from South Africa for Thaumatotibia leucotreta under a systems approach

EFSA Journal ◽  
2021 ◽  
Vol 19 (8) ◽  
Author(s):  
◽  
Claude Bragard ◽  
Francesco Di Serio ◽  
Paolo Gonthier ◽  
Josep Anton Jaques Miret ◽  
...  
Keyword(s):  
South Africa ◽  
Risk Assessment ◽  
Systems Approach ◽  
Thaumatotibia Leucotreta

Partial Cold Treatment of Citrus Fruit for Export Risk Mitigation forThaumatotibia leucotreta(Lepidoptera: Tortricidae) as Part of a Systems Approach

2016 ◽  
Vol 109 (4) ◽  
pp. 1578-1585 ◽  
Author(s):  
S. D. Moore ◽  
W. Kirkman ◽  
S. Albertyn ◽  
C. N. Love ◽  
J. A. Coetzee ◽  
...  
Keyword(s):  
Systems Approach ◽  
Risk Mitigation ◽  
Cold Treatment ◽  
Citrus Fruit

Systems view of integrated water quality monitoring within the requirements of the new national water policy in South Africa

1998 ◽  
Vol 38 (11) ◽  
pp. 141-148 ◽  
Author(s):  
P. Marjanovic ◽  
M. Miloradov
Keyword(s):  
South Africa ◽  
Water Quality ◽  
Water Policy ◽  
Systems Approach ◽  
Water Quality Management ◽  
Water Quality Monitoring ◽  
Point Sources ◽  
Quality Monitoring ◽  
Efficient Manner ◽  
National Water

The new National water policy will change the way water quality is managed in South Africa. The paper considers the water policy and the repercussions it will have for water quality monitoring in South Africa. Using the systems approach the paper discusses an integrated water quality monitoring system for ambient water quality and point and non point sources of aquatic pollution. The proposed methodology makes possible continuos assessment of water quality in an efficient manner so as to support water quality management in South Africa.

scholarly journals Biological Control of a Phytosanitary Pest (Thaumatotibia leucotreta): A Case Study

2021 ◽  
Vol 18 (3) ◽  
pp. 1198
Author(s):  
Sean D. Moore
Keyword(s):  
Biological Control ◽  
Systems Approach ◽  
Microbial Control ◽  
Codling Moth ◽  
Environmental Safety ◽  
Control Measures ◽  
Sub Saharan Africa ◽  
The European Union ◽  
Thaumatotibia Leucotreta ◽  
Sub Saharan

Thaumatotibia leucotreta, known as the false codling moth, is a pest of citrus and other crops in sub-Saharan Africa. As it is endemic to this region and as South Africa exports most of its citrus around the world, T. leucotreta has phytosanitary status for most markets. This means that there is zero tolerance for any infestation with live larvae in the market. Consequently, control measures prior to exporting must be exemplary. Certain markets require a standalone postharvest disinfestation treatment for T. leucotreta. However, the European Union accepts a systems approach, consisting of three measures and numerous components within these measures. Although effective preharvest control measures are important under all circumstances, they are most critical where a standalone postharvest disinfestation treatment is not applied, such as within a systems approach. Conventional wisdom may lead a belief that effective chemical control tools are imperative to achieve this end. However, we demonstrate that it is possible to effectively control T. leucotreta to a level acceptable for a phytosanitary market, using only biological control tools. This includes parasitoids, predators, microbial control, semiochemicals, and sterile insects. Simultaneously, on-farm and environmental safety is improved and compliance with the increasing stringency of chemical residue requirements imposed by markets is achieved.

scholarly journals A Priori and a Posteriori Dietary Patterns among Pregnant Women in Johannesburg, South Africa: The NuPED Study

Nutrients ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 565
Author(s):  
Cornelia Conradie ◽  
Jeannine Baumgartner ◽  
Linda Malan ◽  
Elizabeth A. Symington ◽  
Marike Cockeran ◽  
...  
Keyword(s):  
South Africa ◽  
Pregnant Women ◽  
Dietary Patterns ◽  
Dietary Pattern ◽  
A Priori ◽  
Dietary Quality ◽  
A Posteriori ◽  
Urban South ◽  
Quality Diet ◽  
Nutrient Patterns

Dietary pattern analyses allow assessment of the diet as a whole. Limited studies include both a priori and a posteriori dietary pattern analyses. This study aimed to explore the diet of pregnant women in urban South Africa through both a priori and a posteriori dietary pattern analyses and associated maternal and household factors. Dietary data were collected during early pregnancy using a quantified food frequency questionnaire from 250 pregnant women enrolled in the Nutrition During Pregnancy and Early Development (NuPED) cohort. A priori dietary patterns were determined using the Diet Quality Index-International (DQI-I), and a posteriori nutrient patterns using exploratory factor analysis. Based on the DQI-I, the study population followed a borderline low-quality diet. Three a posteriori nutrient patterns were identified: Pattern 1 “plant protein, iron, thiamine, and folic acid”; pattern 2 “animal protein, copper, vitamin A, and vitamin B12”; pattern 3 “fatty acids and sodium”. Pattern 1 was associated with higher dietary quality (p < 0.001), lower maternal educational level (p = 0.03) and socioeconomic status (p < 0.001). Pattern 3 was significantly associated with lower dietary quality. The low dietary quality among pregnant women residing in urban South Africa should be addressed to ensure optimal maternal and offspring health outcomes.

scholarly journals Needed: A systems approach to improve flood risk mitigation through private precautionary measures

2020 ◽  
Vol 11 ◽  
pp. 100080
Author(s):  
M.H. Barendrecht ◽  
N. Sairam ◽  
L. Cumiskey ◽  
A.D. Metin ◽  
F. Holz ◽  
...  
Keyword(s):  
Flood Risk ◽  
Systems Approach ◽  
Risk Mitigation ◽  
Precautionary Measures

Explaining monotonic ranking functions

2020 ◽  
Vol 14 (4) ◽  
pp. 640-652
Author(s):  
Abraham Gale ◽  
Amélie Marian
Keyword(s):  
Decision Making ◽  
Selection Process ◽  
A Priori ◽  
Data Distribution ◽  
Synthetic Data ◽  
Decision Processes ◽  
Decision Makers ◽  
Ranking Functions ◽  
High School Admissions ◽  
Parameter Values

Ranking functions are commonly used to assist in decision-making in a wide variety of applications. As the general public realizes the significant societal impacts of the widespread use of algorithms in decision-making, there has been a push towards explainability and transparency in decision processes and results, as well as demands to justify the fairness of the processes. In this paper, we focus on providing metrics towards explainability and transparency of ranking functions, with a focus towards making the ranking process understandable, a priori , so that decision-makers can make informed choices when designing their ranking selection process. We propose transparent participation metrics to clarify the ranking process, by assessing the contribution of each parameter used in the ranking function in the creation of the final ranked outcome, using information about the ranking functions themselves, as well as observations of the underlying distributions of the parameter values involved in the ranking. To evaluate the outcome of the ranking process, we propose diversity and disparity metrics to measure how similar the selected objects are to each other, and to the underlying data distribution. We evaluate the behavior of our metrics on synthetic data, as well as on data and ranking functions on two real-world scenarios: high school admissions and decathlon scoring.

E-Learning Business Risk Management with Real Options

2011 ◽  
pp. 187-212
Author(s):  
Georgios N. Angelou
Keyword(s):  
Risk Management ◽  
Real Options ◽  
Information And Communication Technologies ◽  
Risk Mitigation ◽  
A Priori ◽  
Senior Managers ◽  
Investment Performance ◽  
Multiple Risks ◽  
Information And Communication ◽  
E Learning

E-learning markets have been expanding very rapidly. As a result, the involved senior managers are increasingly being confronted with the need to make significant investment decisions related to the elearning business activities. Real options applications to risk management and investment evaluation of Information and Communication Technologies (ICT) have mainly focused on a single and a-priori known option. However, these options are not inherent in any ICT investment. Actually, they must be carefully planned and intentionally embedded in the ICT investment in order to mitigate its risks and increase its return. Moreover, when an ICT investment involves multiple risks, by adopting different series of cascading options we may achieve risk mitigation and enhance investment performance. In this paper, we apply real options to the e-learning investments evaluation. Given the investment’s requirements, assumptions and risks, the goal is to maximize the investment’s value by identifying a good way to structure it using carefully chosen real options.

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