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Mitigating Risks:Safe, Wise and Secure Use of Digital Technologies by Migrant Communities in South Africa
Get PDFAugmented Statistics of Quaternion Random Variables:A Lynchpin of Quaternion Learning Machines
Get PDFLearning machines for vector sensor data are naturally developed in the quaternion domain and are underpinned by quaternion statistics. To this end, we revisit the `augmented' representation basis for discrete quaternion random variables q^a[n], i.e. [ q[n] q^i[n] q^j[n] q^k[n] ]; and demonstrate its pivotal role in the treatment of the generality of quaternion random variables (RV). This is achieved by a rigorous consideration of the augmented quaternion RV, and by involving for additional second order statistics, besides the traditional covariance E{q[n]q*[n]}. To illuminate the usefulness of quaternions, we consider their most well-known application - three-dimensional (3D) orientation and offer an account of augmented statistics for purely imaginary (pure) quaternions. The quaternion statistics presented here can be exploited in the analysis of the existing and the development of novel statistical machine learning methods, hence acting as a lynchpin for quaternion learning machines
Development of Recombinant Bacillus subtilis Spore Vaccines Based on Thymine Auxotrophy as a Biocontainment Strategy
Get PDFBacillus subtilis displaying heterologous antigens show promising efficacy for mucosal immunisation against various viral and bacterial pathogens. In this work, THY-X-CISE system was used to engineer thymine auxotrophic B. subtilis strains to express immunogenic antigens from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and Helicobacter pylori on their spore surface. This system ensures containment of genetically modified (GM) Bacillus spores by inducing cell death upon exogenous thymine depletion. It also eliminates the need for antibiotic resistance gene markers, relying solely on thymine auxotrophy for positive selection. The immunogenicity and efficacy of thymine auxotrophic spores against SARS-CoV-2 and H. pylori were evaluated, along with their ability to induce mucosal immune responses. In murine experiments, a prime-mucosal spore boost strategy using thymine auxotrophic spores expressing SARS-CoV-2 antigens evoked antigen-specific mucosal IgA and is potentially protective, as shown in a hamster model of SARS-CoV-2 infection. Additionally, oral immunisations with thymine auxotrophic spores displaying H. pylori antigens induced mucosal responses and significantly reduced H. pylori colonisation in mice following challenge. In summary, the THY-X-CISE spore vaccine platform is attractive due to its potential for biological containment, rapid and cost-efficient vaccine production, and heat stability. Utilised as a mucosal booster or prophylactic vaccine, spore vaccines could benefit in addressing current and future emerging diseases, enhancing both systemic and mucosal immunity across various viral and bacterial diseases
Widrow-Hoff LMS Adaline Demonstrator for Schools and Colleges
Get PDFThe Widrow-Hoff LMS (or ‘Adaline’) algorithm developedoriginally in 1960 is fundamental to the operation of countlesssignal processing machine learning systems in use eventoday. Bernard Widrow and Ted Hoff famously developedan Adaline machine demonstrator using basic analog offthe shelf components to show how a ‘perceptron’ couldbe trained manually [1]. This paper details the design anddevelopment of a fully digital Adaline Least-Mean-Squarealgorithm demonstrator. The simplistic design presented hereis completely open-source with all code, bill of materialsand 3D casing models available at this Github Repository fordownload and reproduction. The demonstrator enables quickvisualisation of the training and testing of a simple perceptronalgorithm running on the inexpensive Arduino platform. Thetotal costs of the device is estimated to be less than $60 andcould be used in classrooms and colleges the world-over todemonstrate the seminal work of Widrow and Hoff [2] to awide audience
Human Action Recognition Using Multi-Stream Fusion and Hybrid Deep Neural Networks
Get PDFAction Recognition in videos is a topic of interest in the area of computer vision, due to potential applications such as multimedia indexing and surveillance in public areas. In this research, we first propose spatial and temporal Convolutional Neural Network (CNNs), based on transfer learning using ResNet101, GoogleNet and VGG16, for undertaking human action recognition. Besides that, hybrid networks such as CNNRecurrent Neural Network (RNN) models are also exploited as encoder-decoder architectures for video action classification. In particular, different types of RNNs such as Long Short-Term Memory (LSTM), Bidirectional-LSTM (BiLSTM), Gated Recurrent Unit (GRU), and Bidirectional-GRU (BiGRU), are exploited as the decoders for action recognition. To further enhance performance, diverse aggregation networks of CNN and CNN-RNN models are implemented. Specifically, an Average Fusion method is used to integrate spatial and temporal CNNs trained on images, as well as CNN-RNN trained on videos, where the final classification is formed by combining Softmax scores of these models via a late fusion. A total of 22 models (1 motion CNN, 3 spatial CNNs, 12 CNN-RNNs and 6 fusion networks) are implemented which are evaluated using UCF11, UCF50, and UCF101 datasets for performance comparison. The empirical results indicate the significant efficiency of Average Fusion of multiple Spatial-CNNs with one Motion-CNN, and ResNet101-BiGRU, among all the networks for undertaking realistic video action recognition
Unfolding dispositifs:Attempts at digital business education in North Korea
Get PDFScholars have drawn attention to educational spaces as sites of contestation and struggle. Researchers have increasingly scrutinised the power structures and relations that shape educational spaces, particularly in the mobilisation of education to further the economic competitiveness of nation-states. Adopting a dispositif lens, our ethnographic study examines digital business education in a North Korean university. In doing so, we uncover the unstable interplay between a dispositif of paternalist care and a dispositif of discipline, which are both required by the regime to control the development of new digital capabilities, examining the techniques used to develop and restrict digital education. In conclusion, our paper develops new understanding of how digital capabilities, through education, are simultaneously enabled and constrained, and how dispositifs differentially unfold across spac
The forgotten forests:Incorporating temperate peat-forming wet woodlands as nature-based solutions into policy and practice
Get PDFICDP workshop on the Lake Victoria Drilling Project (LVDP):Scientific Drilling of the World’s Largest Tropical Lake
Get PDFLake Victoria, which is bordered by Uganda, Tanzania, Kenya and has a catchment that extends to Rwanda and Burundi, is home to the largest human population surrounding any lake in the world and provides critical resources across eastern Africa. Lake Victoria is also the world’s largest tropical lake by surface area, but it is relatively shallow and without a major inlet, making it very sensitive to changes in climate, and especially hydroclimate. Furthermore, its size creates abundant habitats for aquatic fauna, including the iconic hyper-diverse cichlids, and serves as a major geographic barrier to terrestrial fauna across equatorial Africa. Given Lake Victoria’s importance to the eastern African region, its sensitivity to climate, and its influences on terrestrial and aquatic faunal evolution and dispersal, it is vital to understand the connection between the lake, regional climate, and how the lake size, shape, and depth has changed through its depositional history. This information can only be ascertained by collecting a complete archive of Lake Victoria’s sedimentary record. To evaluate Lake Victoria basin as a potential drilling target, ~50 scientists from 10 countries met in Dar es Salaam, Tanzania in July 2022 for the International Continental Scientific Drilling Program (ICDP) sponsored Lake Victoria Drilling Project (LVDP) workshop. Discussions of the main scientific objectives for a future drilling project included: 1) recovering the Pleistocene and Holocene sedimentary records of Lake Victoria that document the dynamic nature of the lake, including multiple lacustrine and paleosol sequences; 2) establishing the chronology of recovered sediments, including using extensive tephra fingerprinting and other techniques from deposits in the region; 3) reconstructing past climate, environment, lacustrine conditions, and aquatic fauna, using an integrated multi-proxy approach, combined with climate and hydrologic modeling; and 4) connecting new records with existing sedimentary snapshots and fossils exposed in deposits around the lake, tying archeological, paleontological, sedimentological, tectonic, and volcanic findings to new drilling results. The LVDP provides an innovative way to address critical geological, paleontological, climatological, and evolutionary biological questions about Quaternary to modern landscapes and ecosystems in eastern Africa. Importantly, this project affords an excellent opportunity to help develop conservation and management strategies for regional responses to current and future changes in climate, land use, fisheries, and resiliency of at-risk communities in equatorial Africa
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