Automatic Classification of Irregularly Sampled Time Series with Unequal Lengths: A Case Study on Estimated Glomerular Filtration Rate

A patient's estimated glomerular filtration rate (eGFR) can provide important information about disease progression and kidney function. Traditionally, an eGFR time series is interpreted by a human expert labelling it as stable or unstable. While this approach works for individual patients, the time consuming nature of it precludes the quick evaluation of risk in large numbers of patients. However, automating this process poses significant challenges as eGFR measurements are usually recorded at irregular intervals and the series of measurements differs in length between patients. Here we present a two-tier system to automatically classify an eGFR trend. First, we model the time series using Gaussian process regression (GPR) to fill in `gaps' by resampling a fixed size vector of fifty time-dependent observations. Second, we classify the resampled eGFR time series using a K-NN/SVM classifier, and evaluate its performance via 5-fold cross validation. Using this approach we achieved an F-score of 0.90, compared to 0.96 for 5 human experts when scored amongst themselves

Marketing fresh venison in the Eastern Cape Province using a niche marketing strategy

There is a need in the Eastern Cape Province to expand the market for fresh venison. This need is due in part to fluctuations in the export market and fragmentation of consumption in the food industry, which has led to an increased demand for specialised and customised products. A suitable method for addressing these issues and successfully marketing fresh venison in the Eastern Cape Province was required, and based on the findings of this study, niche marketing was found to be a possible marketing method to explore. This study evaluated how a strategy of niche marketing could be used to market fresh venison within the Eastern Cape Province. By analysing this main problem the research attempted to identify and understand the challenges of marketing fresh venison to the final consumer in the Eastern Cape Province and to determine whether niche marketing would be a viable option when taking into account venison’s unique characteristics. Niche marketing was characterised and discussed in the light of other marketing approaches and the most important elements of a successful niche marketing strategy were highlighted. The information resulting from scrutiny of all of these sub-problems was then used to address the challenge of marketing fresh venison to the final consumer. In-depth interviews were deemed most suitable for this study based on the nature of the topic and the depth of expertise of qualified personnel in the Eastern Cape Province fresh venison industry. Consequently, four interviews were conducted with experts in the field. Using the niche marketing concept and the strategy that drives it, namely differentiation, possible niche markets were identified. A strategy of multiple niching was adopted to address the differentiation opportunities available, based on the relevant specialist roles of fresh venison. These differentiation opportunities in turn lead to competitive advantage. Possible niche target markets identified and analysed included the tourist market, travellers (foreign and local) by air and sea, the organic aware market and the pet food market. Branding was found to be an integral element for the niche marketing of venison and is also discussed. The main problems hindering fresh venison marketing in the Eastern Cape Province were found to be consumers’ lack of knowledge of venison, cultural differences and consumer preferences, lack of a formal infrastructure and control, and a lack of accurate data. These challenges need to be addressed before fresh venison can be successfully marketed in the Eastern Cape Province. Research needs to be conducted on the venison industry and formal supply chains and control channels need to be implemented before a quality product in substantial and consistent quantities can be successfully marketed to the final consumer. Consumers and industry personnel must be educated about venison and its merits, and fresh venison must initially target white tablecloth restaurants and specialised delicatessens, where service is as important as the product itself

Cassava: constraints to production and the transfer of biotechnology to African laboratories

Knowledge and technology transfer to African institutes is an important objective to help achieve the United Nations Millennium Development Goals. Plant biotechnology in particular enables innovative advances in agriculture and industry, offering new prospects to promote the integration and dissemination of improved crops and their derivatives from developing countries into local markets and the global economy. There is also the need to broaden our knowledge and understanding of cassava as a staple food crop. Cassava (Manihot esculenta Crantz) is a vital source of calories for approximately 500 million people living in developing countries. Unfortunately, it is subject to numerous biotic and abiotic stresses that impact on production, consumption, marketability and also local and country economics. To date, improvements to cassava have been led via conventional plant breeding programmes, but with advances in molecular-assisted breeding and plant biotechnology new tools are being developed to hasten the generation of improved farmer-preferred cultivars. In this review, we report on the current constraints to cassava production and knowledge acquisition in Africa, including a case study discussing the opportunities and challenges of a technology transfer programme established between the Mikocheni Agricultural Research Institute in Tanzania and Europe-based researchers. The establishment of cassava biotechnology platform(s) should promote research capabilities in African institutions and allow scientists autonomy to adapt cassava to suit local agro-ecosystems, ultimately serving to develop a sustainable biotechnology infrastructure in African countrie

Generation of an hiPSC-Derived Co-Culture System to Assess the Effects of Neuroinflammation on Blood-Brain Barrier Integrity

The blood-brain barrier (BBB) regulates the interaction between the highly vulnerable central nervous system (CNS) and the peripheral parts of the body. Disruption of the BBB has been associated with multiple neurological disorders, in which immune pathways in microglia are suggested to play a key role. Currently, many in vitro BBB model systems lack a physiologically relevant microglia component in order to address questions related to the mechanism of BBB integrity or the transport of molecules between the periphery and the CNS. To bridge this gap, we redefined a serum-free medium in order to allow for the successful co-culturing of human inducible pluripotent stem cell (hiPSC)-derived microglia and hiPSC-derived brain microvascular endothelial-like cells (BMECs) without influencing barrier properties as assessed by electrical resistance. We demonstrate that hiPSC-derived microglia exposed to lipopolysaccharide (LPS) weaken the barrier integrity, which is associated with the secretion of several cytokines relevant in neuroinflammation. Consequently, here we provide a simplistic humanised BBB model of neuroinflammation that can be further extended (e.g., by addition of other cell types in a more complex 3D architecture) and applied for mechanistic studies and therapeutic compound profiling