Virulence and Evolutionary Ecology in the Entomopathogen Bacillus thuringiensis

Bacillus thuringiensis is an entomopathogen in the Bacillus cereus species group, and has been used as a biopesticide for over 50 years. Despite extensive use of B. thuringiensis, there remain questions over its specific ecology compared to other members of the B. cereus group which poses problems for its continued applied use. Tying entomopathogenic ecology to a specific clade within the B. cereus group will limit confusion between B. thuringiensis used in agriculture and more harmful strains. Better understanding of B. thuringiensis ecology can also be used to combat resistance in pest species through selective passaging. The ecology of B. thuringiensis was explored through competitions in Plutella xylostella (diamondback moth) larvae, which showed clade 2 B. thuringiensis have improved fitness in insects compared to clade 1 strains. Additionally, growth rates were compared in vitro, giving different thermal profiles for the two clades. Growth media preference was assessed for B. cereus group species with all favouring protein media over soil-based ones. Selective passaging explored the effects of relatedness and host background on virulence evolution. For relatedness, B. thuringiensis subsp. aizawai was passaged for five rounds in P. xylostella larvae with none, one or two bottlenecking events. These treatments failed to produce any increase in virulence. In the second, B. thuringiensis subsp. entomocidus was passaged either in Cry1Ac-resistant, Cry1Ac-susceptible, alternating rounds of each or coevolved P. xylostella, with all containing a mutagenesis step with ethyl methanesulfonate. Virulence increased in the resistant and coevolved treatments, confirming that resistance is best overcome by passaging in harder-to-kill hosts. The ecological and genetic distinctiveness of clade 2 B. thuringiensis suggests the species should be reclassified to solely this clade, which will limit safety concerns. Selective passaging can improve the virulence of strains, even if the underlying interactions are unknown; it can also provide insight into virulence evolution which would be lost when improving only at the protein level.Leverhulme Trus

An analysis of UK and EU external migration control governance and mechanisms: securitization, manipulation and cooperation

This research analyses the relationship between the UK and the EU in context to external migration control. It has used a combination of Constructivism and Bourdieu to deconstruct the field of analysis and understand how an actor’s behaviour can affect the structure of the external migration control field. Bourdieu was chosen to inform the theoretical framework as his field theory allowed a number of actors to be explored. It also recognises the importance of historical relationships impacting upon current interactions. Bourdieu explain these interactions as habitual or doxical. Habitual behaviours are learnt behaviours that adhere to the norms of the field. Doxical behaviours act against the norms and are used by actors, like the UK, to gain a higher status within the field and increase key capital. The three behaviours that have been explored are; securitization, manipulation and cooperation. In order to identify these behaviours policy documentation from key actors, like Frontex, have been qualitatively coded. The analysis uses three key moments in the history of the UK and the EU to guide the exploration of the data, these are; the Maastricht Treaty (1992), the Amsterdam Treaty (1997) and the UK Immigration Act 2014. The documentation chosen for analysis ranged from unilateral, bilateral and multilateral political agreements. Other documentation includes reports from associated actors that are part of the external migration control field. The documentation reveals the extent to which habitual behaviours dominate the relationship between the actors

THE ROLE OF CONTENT IN REASONING

A programme of research is reported in which the effects of different contents in two deductive reasoning paradigms were investigated. A review of the literature showed that the two main determinants of performance are the logical structure of the task, and non-logical performance variables such as 'matching bias’. Matching is a prime determinant of behaviour in abstract tasks, e.g. Wason's Selection task. This is shown by systematically negating logical rule components. However, a large literature indicates that logical performance is facilitated by using thematic materials

Perspectives on the standards agenda: exploring the agenda's impact on primary teachers' professional identities

This study aimed to investigate teachers' perspectives on the practical implementation of the standards agenda and its impact on their professional identities. Q-methodology was used alongside semi-structured interviews with UK primary school teachers. The study explored the views of 25 teachers in six schools, selected through purposive sampling to give a range of individual and institutional demographics. Teachers in this research commented on the impact the standards agenda has had on parental and societal judgements that affect their identity as professionals. Teachers held differing positions on whether they experienced constraint or flexibility when implementing standards objectives. These differing positions were mainly influenced by whether they taught above or below Year 3. Teachers who found flexibility in the agenda's objectives had less occupational stress and increased ownership of their own actions and the standards agenda. Teachers' positions were complex and changed according to situational influences at a classroom level

Sexual selection and the evolution of altruism: males are more altruistic and cooperative towards attractive females

Explaining altruism through an evolutionary lens has been a challenge for evolutionary theorists. Where altruism towards kin is well understood through kin selection, altruism towards non-kin is an evolutionary puzzle. Contemporary research has found that, through a game-theoretic framework, sexual selection could be an explanation for the evolution of altruism. Research suggests that males are more altruistic towards females they are interested in engaging with, sexually or romantically when distributing stakes in economic games. This study, adopting a between-groups design, tested the sexual selection explanation for altruism by asking participants to self-report altruistic and cooperative intention when reading moral scenarios accompanied by attractive or unattractive images. We find that participants, particularly males, report being more altruistic and cooperative when viewing an attractive image of a female. This study replicates the sexual selection hypothesis in explaining altruism through an alternative experimental framework to game theory