2,341 research outputs found

    Enabling Normalized Systems in Practice – Exploring a Modeling Approach

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    Contemporary organizations are required to adapt to a changing environment in an agile way, which is often deemed very challenging. Normalized Systems (NS) theory attempts to build highly evolvable software systems by using systems theory as its theoretical underpinning. A modeling method which supports the identification of the NS elements, required for building NS sofware in practice, is currently missing. Therefore, the paper introduces an approach for creating both data models and processing models in the context of NS, as well as their integration. It is discussed how these models can be taken as the input for the actual creation of evolutionary prototypes by using an earlier developed supporting tool. The modeling approach and its suitability for feeding the tool are evaluated to discover their current strengths and weaknesses

    Characterising infant and young child feeding practices and the consumption of poultry products in rural Tanzania: A mixed methods approach

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    Suboptimal breastfeeding practices, early initiation of complementary feeding, and monotonous cereal‐based diets have been implicated as contributors to continuing high rates of child undernutrition in sub‐Saharan Africa. Nutrition‐sensitive interventions, including agricultural programs that increase access to nutrient‐rich vegetables, legumes, and animal‐source foods, have the potential to achieve sustainable improvements in children's diets. In the quest to evaluate the efficacy of such programs in improving growth and development in the first 2 years of life, there is a role for mixed methods research to better understand existing infant and young child feeding practices. This analysis forms part of a longitudinal study assessing the impact of improvements to poultry health and crop production on diets and growth of 503 randomly selected children from eight rural communities in Manyoni District in central Tanzania. Using an explanatory sequential design, the quantitative phase of data collection was conducted between May 2014 and May 2016, comprising six monthly structured questionnaires, four monthly household‐level documentation of chicken and egg consumption, and fortnightly records of children's breastfeeding status. The subsequent qualitative phase involved in‐depth interviews with a subset of 39 mothers in October 2016. Breastfeeding was almost universal (96.8%) and of long duration (mean = 21.7 months, SD = 3.6), but early initiation of complementary feeding was also common (74.4%; mean = 4.0 months, SD = 1.8), overwhelmingly driven by maternal perceptions of insufficient milk supply (95.0%). Chicken and eggs were infrequently eaten, but close associations between maternal and child consumption patterns (p < .001) suggest the potential for strategies that increase household‐level consumption to bring nutritional benefits to young children

    Monitoring compliance of CITES lion bone exports from South Africa

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    From 2008 to 2018, South Africa permitted the export of captive-bred African lion (Panthera leo) skeletons to Southeast Asia under CITES Appendix II. Legal exports rose from approximately 50 individuals in 2008 to a maximum of 1,771 skeletons in 2016, and has led to ongoing concerns over possible laundering of non-lion, multiple-source and wild-sourced bones. South Africa is required under its obligations to CITES to employ mechanisms for monitoring and reporting trade, and to limit the potential for illegal trade and laundering of lion and other large felid bones. Monitoring tools for legal trade are critical to compliance with CITES. Here we evaluate the CITES-compliance procedure implemented by South Africa for export of lion bones and identify six essential general points for consideration in the implementation of animal export quota compliance protocols. We provide specific insight into the South African lion bone export monitoring system through: i) outlining the protocols followed; ii) assessing the utility of cranial morphology to identify species; iii) evaluating skeleton consignment weight as a monitoring tool; and iv) presenting molecular (DNA) species assignment and pairwise-comparative sample matching of individuals. We describe irregularities and illicit behaviour detected in the 2017 and 2018 lion bone quotas. Notably, we report that the compliance procedure successfully identified and prevented the attempted laundering of a tiger (P. tigris) skeleton in 2018. We emphasise the utility of mixed-method protocols for the monitoring of compliance in CITES Appendix II export quota systems

    Regional differences in plastic ingestion among Southern Ocean fur seals and albatrosses

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    Weprovide data on regional differences in plastic ingestion for two Southern Ocean top predators: Arctocephalus fur seals and albatrosses (Diomedeidae). Fur seals breeding on Macquarie Island in the 1990s excreted small (mainly 2–5 mm) plastic fragments, probably derived secondarily from myctophid fish. No plastic was found in the scats of these seals breeding on three islands in the southwest Indian and central South Atlantic Oceans, despite myctophids dominating their diets at these locations. Compared to recent reports of plastic ingestion by albatrosses off the east coast of South America, we confirm that plastic is seldom found in the stomachs of Thalassarche albatrosses off South Africa, but found no Diomedea albatrosses to contain plastic, compared to 26% off South America. The reasons for such regional differences are unclear, but emphasize the importance of reporting negative as well as positive records of plastic ingestion by marine biota.National Research Foundation and the Universities of Cape Town and Pretoria.http://www.elsevier.com/locate/marpolbul2017-03-30hb2016Mammal Research InstituteZoology and Entomolog

    Roan antelope Hippotragus equinus in Africa : a review of abundance, threats and ecology

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    1. The roan antelope Hippotragus equinus, Africa’s second largest antelope species, is widely distributed throughout Africa. Many populations are isolated, occur at low densities, and are declining. The species’ interactions with and adaptations to the diverse environmental conditions throughout its geographic range remain largely unknown. Most studies have taken place in southern Africa, near the range limit for the species; few studies have been conducted on the historically large Central and West African populations. 2. We reviewed available published and accessible unpublished data related to the ecology of roan antelope. We aim to: 1) review available taxonomic, abundance, distribution, and population trend data; 2) describe the threats faced by the roan antelope, and establish whether sufficient data exist to describe its ecological requirements; and 3) highlight the relevance of conserving this species throughout Africa and suggest where research on survival requirements should be focussed. 3. Roan antelope populations throughout Africa are declining due to natural and anthropogenic threats. Methodological irregularities result in uncertainty and non-comparable population data between studies. Large gaps exist in our knowledge of roan antelope diet and regional movements. Information on the population genetics of roan antelope is needed in order to assess the connectedness of different populations. 4. Data deficiency severely impedes our ability to employ powerful analytical methods aimed at understanding and predicting population persistence and viability, and to model envisaged threats from impending climate change. A unified approach to fundamental ecological research is required to inform the conservation and management of large rare mammalian ungulates such as the roan antelope in Africa.University of Pretoria and South African National Research Foundation.http://onlinelibrary.wiley.com/journal/10.1111/(ISSN)1365-29072017-04-30hb2016Mammal Research InstituteZoology and Entomolog

    CD47, a multi-facetted target for cancer immunotherapy

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    CD47 is a ubiquitously expressed immunoregulatory protein best known for its so-called 'don't eat me' function that prevents phagocytic removal of healthy cells by the immune system. Many types of cancer present high levels of this don't eat me signal on their surface, thereby disrupting anti-cancer immune responses. Based on this observation, CD47 has become a prominent target in the field of cancer immunotherapy. Indeed, pre-clinical studies have shown therapeutic benefit of anti-CD47 antibodies in solid cancers and most notably B-cell malignancies. However, CD47 is also involved in various other important cellular processes, such as angiogenesis, cancer cell death and regulation of T-cell immunity, which can be modulated via interactions with thrombospondin-1. The therapeutic outcome of CD47-targeted immunotherapy therefore relies on the combined effects of all these processes. Here we will review the various physiological functions of CD47 and their implications in cancer biology. Further, we will review ongoing efforts and provide perspectives for exploiting CD47 as an immunotherapeutic target in cancer

    Polysaccharide-derived mesoporous materials (StarbonÂź) for sustainable separation of complex mixtures

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    The recovery and separation of high value and low volume extractives are a considerable challenge for the commercial realisation of zero-waste biorefineries. Using solid-phase extractions (SPE) based on sustainable sorbents is a promising method to enable efficient, green and selective separation of these complex extractive mixtures. Mesoporous carbonaceous solids derived from renewable polysaccharides are ideal stationary phases due to their tuneable functionality and surface structure. In this study, the structure-separation relationships of thirteen polysaccharide-derived mesoporous materials and two modified types as sorbents for ten naturally-occurring bioactive phenolic compounds were investigated. For the first time, a comprehensive statistical analysis of the key molecular and surface properties influencing the recovery of these species was carried out. The obtained results show the possibility of developing tailored materials for purification, separation or extraction, depending on the molecular composition of the analyte. The wide versatility and application span of these polysaccharide-derived mesoporous materials offer new sustainable and inexpensive alternatives to traditional silica-based stationary phases
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