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Modelling Martian dust storms: feedbacks between dust and atmospheric circulation at a hierarchy of scales
We employ numerical models of Mars at spatial scales ranging from global to a few metres in order to investigate both the impact of increasing dust loading on atmospheric circulations and the role of different atmospheric circulation components on dust lifting, transport and on dust storm decay
Aviation's role in earth resources surveys
The role of satellites designed to make a wide variety of earth observations is discussed along with the renewed interest in the use of aircraft as platforms for similar and complementary earth resources surveys. Surveys covering the areas of forestry, agriculture, hydrology, oceanography, geology, and geography are included. Aerials surveys equipped for nonphotographic remote sensing and aircraft flights synchronized with satellite observations to provide correlated data are discussed. Photographs are shown to illustrate preliminary results from several of the test sites
Preventive measures in infancy to reduce under-five mortality: a case-control study in The Gambia.
OBJECTIVE: To investigate the relationship between child mortality and common preventive interventions: vaccination, trained birthing attendants, tetanus toxoid during pregnancy, breastfeeding and vitamin A supplementation. METHODS: Case-control study in a population under demographic surveillance. Cases (n = 141) were children under five who died. Each was age and sex-matched to five controls (n = 705). Information was gathered by interviewing primary caregivers. RESULTS: All but one of the interventions - whether the mother had received tetanus toxoid during pregnancy - were protective against child mortality after multivariate analysis. Having a trained person assisting at child birth (OR 0.2 95% CI 0.1-0.4), receiving all vaccinations by 9 months of age (OR 0.1; 95% CI 0.01-0.3), being breastfed for more than 12 months (Children breastfed between 13 and 24 months OR 0.1 95% CI 0.03-0.3, more than 25 months OR 0.1 95% CI 0.01-0.5) and receiving vitamin A supplementation at or after 6 months of age (OR 0.05; 95% CI 0.01-0.2) were protective against child death. CONCLUSIONS: This study confirms the value of at least four available interventions in the prevention of under-five death in The Gambia. It is now important to identify those who are not receiving them and why, and to intervene to improve coverage across the population
A renormalisation approach to excitable reaction-diffusion waves in fractal media
Of fundamental importance to wave propagation in a wide range of physical phenomena is the structural geometry of the supporting medium. Recently, there have been several investigations on wave propagation in fractal media. We present here a renormalization approach to the study of reaction-diffusion (RD) wave propagation on finitely ramified fractal structures. In particular we will study a Rinzel-Keller (RK) type model, supporting travelling waves on a Sierpinski gasket (SG), lattice
Whole body interaction in abstract domains
Whole Body Interaction appears to be a good fit of interaction style for some categories of application domain, such as the motion capture of gestures for computer games and virtual physical sports. However, the suitability of whole body interaction for more abstract application domains is less apparent, and the creation of appropriate whole body interaction designs for complex abstract areas such as mathematics, programming and musical harmony remains challenging. We argue, illustrated by a detailed case study, that conceptual metaphor theory and sensory motor contingency theory offer analytic and synthetic tools whereby whole body interaction can in principle be applied usefully to arbitrary abstract application domains. We present the case study of a whole body interaction system for a highly abstract application area, tonal harmony in music. We demonstrate ways in which whole body interaction offers strong affordances for action and insight in this domain when appropriate conceptual metaphors are harnessed in the design. We outline how this approach can be applied to abstract domains in general, and discuss its limitations
Identification of the key compounds responsible for Cheddar cheese flavour
End of Project ReportThere is a poor understanding of
the relationship between organoleptic assessment of cheese and quantitative
analysis of flavour compounds. Further, the contribution of particular cheese-making parameters such as ripening temperature and starter culture has not been
fully elucidated.
During the ripening of most cheese varieties complex chemical conversions occur within the
cheese matrix. In most cheese varieties breakdown of protein is the most important flavour
development pathway. The primary cheese protein, casein, is degraded enzymatically to
short peptides and free amino acids. The agents primarily responsible for these conversions
are the residual rennet that is retained in the cheese curd at the end of the manufacturing
phase and the proteinases and peptidases that are associated with the starter bacteria. While
the rate and degree of proteolysis are of vital significance for desired flavour development,
the direct products of proteolysis do not fully define cheese flavour. Much research is now
demonstrating that the further biochemical and chemical conversions of the products of
proteolysis, in particular the amino acids, are necessary for full flavour development. The
products produced by these pathways are volatile at low boiling points and are thus
released during mastication of the cheese in the mouth. Many of these volatile compounds
contribute to the flavour sensation experienced by the consumer. A very wide spectrum of
such compounds have been isolated from cheese, in excess of two hundred in some cheese
varieties. It is now generally accepted that there is no individual compound which defines
cheese flavour completely and that the flavour sensation is the result of numerous
compounds present in the correct proportions. This has become known as the Component
Balance Theory .
The application of modern analytical techniques as proposed in this project would provide
a greater understanding of the significant flavour compounds in Cheddar cheese and help
to identify the impact of specific cheese-making parameters such as starter flora and
ripening temperature on the production of volatile flavour compounds. This data would
assist the general programme on flavour improvement of cheese which should ultimately
benefit the cheese manufacturer.
Hence this project set out to develop methods to identify the key flavour compounds in
Cheddar cheese. These techniques would then be applied to experimental and commercial
cheeses during ripening in an effort to identify key compounds and the influence of starter
cultures and ripening temperature on their production.Department of Agriculture, Food and the Marin
Development of a botanical plant protection product from Larix by-products to protect grapevine from Plasmopara viticola
Extracts from European Larch (Larix decidua) were shown to be efficient to control grapevine downy mildew (Plasmopara viticola) under controlled and field conditions. Larixyl acetate and larixol were identified as the active compounds
The fatty acid site is coupled to functional motifs in the SARS-CoV-2 spike protein and modulates spike allosteric behaviour
The SARS-CoV-2 spike protein is the first contact point between the SARS-CoV-2 virus and host cells and mediates membrane fusion. Recently, a fatty acid binding site was identified in the spike (Toelzer et al. Science 2020). The presence of linoleic acid at this site modulates binding of the spike to the human ACE2 receptor, stabilizing a locked conformation of the protein. Here, dynamical-nonequilibrium molecular dynamics simulations reveal that this fatty acid site is coupled to functionally relevant regions of the spike, some of them far from the fatty acid binding pocket. Removal of a ligand from the fatty acid binding site significantly affects the dynamics of distant, functionally important regions of the spike, including the receptor-binding motif, furin cleavage site and fusion-peptide-adjacent regions. Simulations of the D614G mutant show differences in behaviour between these clinical variants of the spike: the D614G mutant shows a significantly different conformational response for some structural motifs relevant for binding and fusion. The simulations identify structural networks through which changes at the fatty acid binding site are transmitted within the protein. These communication networks significantly involve positions that are prone to mutation, indicating that observed genetic variation in the spike may alter its response to linoleate binding and associated allosteric communication
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