The transition from health to sickness via the chloroplast

Microbe associated molecular pattern (MAMP) receptors in plants recognize MAMPs and activate basal defences; however a complete understanding of the molecular and physiological mechanisms conferring immunity remains elusive. Pathogens suppress active defence in plants through the combined action of effector proteins. This talk presents results showing the chloroplast as a key component of early immune responses. MAMP perception triggers the rapid, large-scale suppression of nuclear encoded chloroplast-targeted genes (NECGs). Virulent Pseudomonas syringae effectors reprogramme NECG expression in Arabidopsis, target the chloroplast and inhibit photosynthetic CO2 assimilation through disruption of photosystem II. This activity prevents a chloroplastic reactive oxygen burst. These physiological changes precede bacterial multiplication and coincide with pathogen-induced abscisic acid (ABA) accumulation. MAMP pretreatment protects chloroplasts from effector manipulation, whereas application of ABA or the inhibitor of photosynthetic electron transport, DCMU, abolishes the MAMP-induced chloroplastic reactive oxygen burst, and enhances growth of a P. syringae hrpA mutant that fails to secrete effectors.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Complexity and Fly Swarms

Complexity is the study of phenomena that emerge from a collection of interacting objects and arises in many systems throughout physics, biology, finance, economics and more. Certain kinds of complex systems can be described by self-organized criticality (SOC). An SOC system is one that is internally driven towards some critical state. Recent experimental work suggests scaling behavior of fly swarms is one of the hallmarks of an SOC system. Our goal is to look for SOC behavior in computational models of fly swarms

Characterisation and thick film metallisation of aluminium nitrade substrates

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The Relationship of Human Psychological Characteristics with Athletic Performance

The purpose of this paper is to report the findings of a literature review summary on the topic of the relationship of human psychological characteristics with athletic performance. Two research questions guided its development: (1) Is there any evidence that there is a relationship between individual human psychological characteristics and athletic performance? (2) If there is any evidence that there is a relationship between individual human psychological characteristics and athletic performance, is there further evidence that those individual characteristics translate in some way into group dynamics or attributes that may similarly influence team performance

Hartley Site (FaNp-19) : interpreting a transitional Avonlea/Old Women's faunal assemblage

The Hartley site (FaNp-19) is a Late Prehistoric multi-component habitation site containing a Mortlach and an Avonlea/Old Women's occupation. The faunal assemblage from the Avonlea/Old Women's occupation contains at least 22 species of vertebrates and at least four genera of invertebrates. These materials have been analyzed to establish the seasonality of the occupation as well as the palaeoenvironmenat and biogeography of the site area. Analyses of the faunal material helped to establish that the occupation was a single event. The occupation began in the late fall/early winter and continued through to the late winter/early spring. The environment of the region appears to have been similar to the modem environment although the site area itself may have been slightly damper. Several factors, including the site positioning and the wide diversity of faunal species, may relate to the season of occupation. Faunal assemblages from sites such as Amisk, Long Creek, Lucky Strike, Tschetter, Lebret and Miniota in Saskatchewan and southern Manitoba show some similarities to the Hartley site remains. It is proposed that the procurement and settlement strategies in this region reflect the season of occupation. Sites with a winter seasonality are associated with areas of trees such as the Aspen Parkland or valley complexes and are often occupied for extended periods of time. These occupations may begin with a single large bison kill, but this may be followed through the winter by smaller attritional style kills. Sites which are occupied into the spring will exhibit a particularly diverse range of species

The breeding ecology of whimbrel (Numenius Phaeopus) in Shetland: with particular reference to the effects of agricultural improvement of Heathland nesting habitats

The effect of re-seeding of heathland on the breeding ecology of whimbrel in Shetland was studied from 1986-1988, on five study sites located on the islands of Unst and Fetlar. A total of 36-45 pairs bred on these study sites in each year, and a large proportion of the breeding adults were individually colour ringed. Heathland was the main nesting habitat for whimbrel. Established pastures and areas ploughed or harrowed before re-seeding were avoided as nesting habitats, but some pairs nested on areas subjected only to surface re-seeding. Avoidance of ploughed or harrowed re-seeds was associated with changes in vegetation composition and structure, and such re-seeds lacked attributes important in the selection of nest-sites by whimbrel. Habitat change was less marked in surface re-seeds. Ploughed or harrowed re-seeds were used extensively as feeding habitat by adults during the pre-laying period, and evidence was obtained to indicate that re-seeding improved feeding conditions for adults. Measures of breeding success were positively correlated with egg volume, and negatively correlated with laying date. However, the improved feeding conditions on re-seeds for females prior to laying were unlikely to have provided major benefits for breeding success via effects on either egg volume or laying date. Approximately 30% of all broods studied used re-seeds at some stage prior to fledging. Although some broods did show preferences for this habitat, there was little evidence that this was associated with either, decreasing the risk of predation on chicks, or improving chick food supply. The survival of chicks to fledging did not vary according to the habitat-use of broods. Both nesting densities and productivity varied between study sites. The possibility that areas of heathland differ in their suitability as breeding habitat for whimbrel is considered, and the implications of this in assessing the effects of re-seeding heathland are discussed. Over the study period the overall production of fledglings from study sites was probably in excess of that required to balance adult mortality. This result is consistent with the current increase of the whimbrel population in Shetland