6 research outputs found

    Analysis of the Yellow Bean Corridor in Tanzania

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    The yellow bean value chain in Tanzania was necessary to understand value chain. The objective of the survey was to characterize and explore trade of yellow bean grain and potential seed. The survey collected data and grain samples from 298 grain traders (including wholesalers, exporters, aggregators, and retailers) and 64 potential seed traders (large and retail traders) from 12 regions across four administrative zones in Tanzania. The grain samples collected were for DNA analyses. Results show existence of an established yellow bean corridor across Tanzania and the region at large (Burundi, DRC, Kenya, Rwanda, Uganda, Zambia) and demonstrated a huge market pull in the Eastern and Southern Africa regions. There are also strong perceptions on the organoleptic quality of various yellow bean grains and varieties that are traced to their sources

    Evolutionary remodelling of N-terminal domain loops fine-tunes SARS-CoV-2 spike

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    The emergence of SARS-CoV-2 variants has exacerbated the COVID-19 global health crisis. Thus far, all variants carry mutations in the spike glycoprotein, which is a critical determinant of viral transmission being responsible for attachment, receptor engagement and membrane fusion, and an important target of immunity. Variants frequently bear truncations of flexible loops in the N-terminal domain (NTD) of spike; the functional importance of these modifications has remained poorly characterised. We demonstrate that NTD deletions are important for efficient entry by the Alpha and Omicron variants and that this correlates with spike stability. Phylogenetic analysis reveals extensive NTD loop length polymorphisms across the sarbecoviruses, setting an evolutionary precedent for loop remodelling. Guided by these analyses, we demonstrate that variations in NTD loop length, alone, are sufficient to modulate virus entry. We propose that variations in NTD loop length act to fine-tune spike; this may provide a mechanism for SARS-CoV-2 to navigate a complex selection landscape encompassing optimisation of essential functionality, immune-driven antigenic variation and ongoing adaptation to a new host

    Marketā€led options to scale up legume seeds in developing countries: Experiences from the Tropical Legumes Project

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    There are several hurdles to ensure sustainable seed production and consistent flow of improved legume varieties in subā€Saharan Africa (SSA) and South Asia (SA). The unreliable demand, autogamous nature of most of the grain legumes, and slow variety replacement rate by smallholder farmers do not provide strong incentive for private seed companies to invest in legume seed business. Unless a well thoughtā€out and comprehensive approach to legume seed delivery is developed, current seed shortages will continue, eroding emerging market opportunities. The experiences reported here are collated through a 10ā€year partnership project, the Tropical Legumes in SSA and SA. It fostered innovative publicā€“private partnerships in joint testing of innovative marketā€led seed systems, skills and knowledge enhancement, deā€risking private sector initiatives that introduced in new approaches and previously overlooked entities in technology delivery. As new public and private seed companies, individual seed entrepreneurs and farmer organizations emerged, the existing ones enhanced their capacities. This resulted in significant rise in production, availability and accessibility of various seed grades of newly improved and farmer demanded legume varieties in the target countries

    Development and Parameterization of a Rain- and Fire-driven Model for Exploring Elephant Effects in African Savannas

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