Understanding the dehydrogenation mechanism of tetrahydrocarbazole over palladium using a combined experimental and density functional theory approach

The mechanism of the dehydrogenation of tetrahydrocarbazole to carbazole over palladium has been examined for the first time. By use of a combination of deuterium exchange experiments and density functional theory calculations, a detailed reaction profile for the aromatization of tetrahydrocarbazole has been identified and validated by experiment. As with many dehydrogenation reactions, the initial hydrogen abstraction is found to have the highest reaction barrier. Tetrahydrocarbazole has four hydrogens which can, in principle, be cleaved initially; however, the theory and experiment show that the reaction is dominated by the cleavage of the carbon hydrogens at the carbon atoms in positions 1 and 4. The two pathways originating from these two C-H bond cleavage processes are found to have similar reaction energy profiles and both contribute to the overall reaction.

A comprehensive comparison between generalized incidence calculus and Dempster-Shafer theory of evidence.

Dealing with uncertainty problems in intelligent systems has attracted a lot of attention in the AI community. Quite a few techniques have been proposed. Among them, the Dempster-Shafer theory of evidence (DS theory) has been widely appreciated. In DS theory, Dempster's combination rule plays a major role. However, it has been pointed out that the application domains of the rule are rather limited and the application of the theory sometimes gives unexpected results. We have previously explored the problem with Dempster's combination rule and proposed an alternative combination mechanism in generalized incidence calculus. In this paper we give a comprehensive comparison between generalized incidence calculus and the Dempster-Shafer theory of evidence. We first prove that these two theories have the same ability in representing evidence and combining DS-independent evidence. We then show that the new approach can deal with some dependent situations while Dempster's combination rule cannot. Various examples in the paper show the ways of using generalized incidence calculus in expert systems.

Civic Republicanism and Green Political Theory

Republicanism and in particular the civic republican tradition is not often one that one finds in discusions and debates within green political theory. It is interesting to note the relative lack of engagement between republican political theory and green political theory, unlike for example the research one can find on the relationship between green politics/political theory and liberalism, socialism and feminism. This is remarkable, given, as I hope to establish in this paper, the large areas of overlap between both, and in particular the compatibility of republican ideas and positions with key priciples and objectives of green theory, paricularly in relation to active citizenship, the centrality of recognising vulnerability and a commitment to liberty (as non-domination) and pluralism as key components of the transition to a more sustainable society.

Discursive Control, Non-Domination and Hegelian Recognition Theory: Marrying Pettit’s Account(s) of Freedom with a Pippinian/Brandomian Reading of Hegelian Agency

The aim of this article is to combine Pettit’s account(s) of freedom, both his work on discursive control and on non-domination, with Pippin’s and Brandom’s reinterpretation of Hegelian rational agency and the role of recognition theory within it. The benefits of combining these two theories lie, as the article hopes to show, in three findings: first, re-examining Hegelian agency in the spirit of Brandom and Pippin in combination with Pettit’s views on freedom shows clearly why and in which way a Hegelian account of rational agency can ground an attractive socio-political account of freedom; second, the reconciling of discursive control and non-domination with Hegelian agency shows how the force and scope of recognition become finally tangible, without either falling into the trap of overburdening the concept, or merely reducing it to the idea of simple respect; third, the arguments from this article also highlight the importance of freedom as non-domination and how this notion is, indeed, as Pettit himself claims, an agency-freedom which aims at successfully securing the social, political, economic and even (some) psychological conditions for free and autonomous agency.

Integrating personality research and animal contest theory:Aggressiveness in the green swordtail xiphophorus helleri

Aggression occurs when individuals compete over limiting resources. While theoretical studies have long placed a strong emphasis on context-specificity of aggression, there is increasing recognition that consistent behavioural differences exist among individuals, and that aggressiveness may be an important component of individual personality. Though empirical studies tend to focus on one aspect or the other, we suggest there is merit in modelling both within- and among-individual variation in agonistic behaviour simultaneously. Here, we demonstrate how this can be achieved using multivariate linear mixed effect models. Using data from repeated mirror trials and dyadic interactions of male green swordtails, Xiphophorus helleri, we show repeatable components of (co)variation in a suite of agonistic behaviour that is broadly consistent with a major axis of variation in aggressiveness. We also show that observed focal behaviour is dependent on opponent effects, which can themselves be repeatable but were more generally found to be context specific. In particular, our models show that within-individual variation in agonistic behaviour is explained, at least in part, by the relative size of a live opponent as predicted by contest theory. Finally, we suggest several additional applications of the multivariate models demonstrated here. These include testing the recently queried functional equivalence of alternative experimental approaches, (e.g., mirror trials, dyadic interaction tests) for assaying individual aggressiveness. © 2011 Wilson et al.

Select Document: Sir George Radcliffe’s “Original of Government” (1639) and Absolutist Political Theory in Stuart Ireland

A seventeenth-century manuscript miscellany, which once belonged to Archbishop James Ussher of Armagh, contains a short treatise on the origins of government by Sir George Radcliffe. Radcliffe was legal assistant to Sir Thomas Wentworth, lord deputy of Ireland (from January 1640 earl of Strafford and lord lieutenant). The treatise insisted on the divine origin of all human political power and implied that the best form of government was absolute monarchy, in which the monarch was free of all human law and subject to divine restraint alone. It will be suggested below that the composition of this treatise can be dated to the summer of 1639. This introduction will offer an outline of Radcliffe’s education and political career, explain the genesis of his treatise on government, point out some pertinent aspects of its argument, and finally assess the document’s significance.

Scattering theory of cooling and heating in optomechanical systems

We present a one-dimensional scattering theory which enables us to describe a wealth of effects arising from the coupling of the motional degree of freedom of scatterers to the electromagnetic field. Multiple scattering to all orders is taken into account. The theory is applied to describe the scheme of a Fabry-Perot resonator with one of its mirrors moving. The friction force, as well as the diffusion, acting on the moving mirror is derived. In the limit of a small reflection coefficient, the same model provides for the description of the mechanical effect of light on an atom moving in front of a mirror.

Explaining the relationship between ingroup identification and intergroup bias following recategorization: A self-regulation theory analysis

We tested the hypothesis that regulation of discrepancies between perceived actual and ideal differentiation between the ingroup and outgroup could help to explain the relationship between ingroup identification and intergroup bias when participants are recategorized into a superordinate group. Replicating previous findings, we found that following recategorization, identification was positively related to intergroup bias. No such differences emerged in a control condition. However, we also, in the recategorization condition only, observed a positive association between ingroup identification and the perceived discrepancy between actual and ideal degree of differentiation from the outgroup: at higher levels of identification, participants increasingly perceived the ingroup to be less differentiated from the outgroup than they would ideally like. This tendency mediated the relationship between identification and bias. We discuss the theoretical, methodological and practical implications of these findings.