An expert-driven causal model of the rhino poaching problem

A significant challenge in ecological modelling is the lack of complete sets of high-quality data. This is especially true in the rhino poaching problem where data is incomplete. Although there are many poaching attacks, they can be spread over a vast surface area such as in the case of the Kruger National Park in South Africa, which is roughly the size of Israel. Bayesian networks are useful reasoning tools and can utilise expert knowledge when data is insufficient or sparse. Bayesian networks allow the modeller to incorporate data, expert knowledge, or any combination of the two. This flexibility of Bayesian networks makes them ideal for modelling complex ecological problems. In this paper an expert-driven model of the rhino poaching problem is presented. The development as well as the evaluation of the model is performed from an expert perspective. Independent expert evaluation is performed in the form of queries that test different scenarios. Structuring the rhino poaching problem as a causal network yields a framework that can be used to reason about the problem, as well as inform the modeller of the type of data that has to be gathered

A change navigation-based, scenario planning process within a developing world context from an Afro-centric leadership perspective

Orientation: In the hyper turbulent context faced currently by organisations, more flexible strategic planning approaches, such as scenario planning which take into account a more comprehensive range of possible futures for an organisation, will position organisations better than conventional forecast and estimates that depend only on a single, linearly extrapolated, strategic response. Research purpose: This study aimed to investigate how scenario-based planning (a strictly cognitive management tool) can be combined with organisational change navigation (a practice addressing the emotionality of change) and how this integrated process should be aligned with the prerequisites imposed by a developing country context and an Afro-centric leadership perspective in order to make the process more context relevant and aligned. Motivation for the study: The integration of organisational change navigation with conventional scenario based planning, as well as the incorporation of the perquisites of a developing countries and an Afro-centric leadership perspective, will give organisations a more robust, holistic strategic management tool that will add significantly more value within a rapidly, radically and unpredictably changing world. Research design, approach and method: The adopted research approach comprised a combination of the sourcing of the latest thinking in the literature (the ‘theory’) as well as the views of seasoned practitioners of scenario planning (the ‘practice’) through an iterative research process, moving between theory and practice, back to practice and finally returning to theory in order to arrive at a validated expanded and enhanced scenario-based planning process which is both theory and practice ‘proof’. Main findings: A management tool incorporating the change navigation and the unique features of developing countries and Afro-centric leadership was formulated and empirically validated. This management tool is referred to as a change navigation based, scenario planning process (CNBSPP). Practical/managerial implications: CNBSPP is available for use by organisations wishing to apply a strategic planning tool that fits within a developing country context and an Afro-centric leadership approach. Contribution/value add: The research makes a unique contribution to the current level of knowledge by integrating two disciplines usually practised independently of one another, namely scenario-based planning and organisational change navigation. It also embedded the process into a different context of application, that is, the developed world as viewed from an Afro-centric leadership perspective

Vorapaxar in the secondary prevention of atherothrombotic events

Item does not contain fulltextBACKGROUND: Thrombin potently activates platelets through the protease-activated receptor PAR-1. Vorapaxar is a novel antiplatelet agent that selectively inhibits the cellular actions of thrombin through antagonism of PAR-1. METHODS: We randomly assigned 26,449 patients who had a history of myocardial infarction, ischemic stroke, or peripheral arterial disease to receive vorapaxar (2.5 mg daily) or matching placebo and followed them for a median of 30 months. The primary efficacy end point was the composite of death from cardiovascular causes, myocardial infarction, or stroke. After 2 years, the data and safety monitoring board recommended discontinuation of the study treatment in patients with a history of stroke owing to the risk of intracranial hemorrhage. RESULTS: At 3 years, the primary end point had occurred in 1028 patients (9.3%) in the vorapaxar group and in 1176 patients (10.5%) in the placebo group (hazard ratio for the vorapaxar group, 0.87; 95% confidence interval [CI], 0.80 to 0.94; P<0.001). Cardiovascular death, myocardial infarction, stroke, or recurrent ischemia leading to revascularization occurred in 1259 patients (11.2%) in the vorapaxar group and 1417 patients (12.4%) in the placebo group (hazard ratio, 0.88; 95% CI, 0.82 to 0.95; P=0.001). Moderate or severe bleeding occurred in 4.2% of patients who received vorapaxar and 2.5% of those who received placebo (hazard ratio, 1.66; 95% CI, 1.43 to 1.93; P<0.001). There was an increase in the rate of intracranial hemorrhage in the vorapaxar group (1.0%, vs. 0.5% in the placebo group; P<0.001). CONCLUSIONS: Inhibition of PAR-1 with vorapaxar reduced the risk of cardiovascular death or ischemic events in patients with stable atherosclerosis who were receiving standard therapy. However, it increased the risk of moderate or severe bleeding, including intracranial hemorrhage. (Funded by Merck; TRA 2P-TIMI 50 ClinicalTrials.gov number, NCT00526474.)