Brunel University London

About: Brunel University London is a education organization based out in London, United Kingdom. It is known for research contribution in the topics: Context (language use) & Large Hadron Collider. The organization has 10918 authors who have published 29515 publications receiving 893330 citations. The organization is also known as: Brunel & University of Brunel.

Complexity of random energy landscapes, glass transition, and absolute value of the spectral determinant of random matrices.

Abstract: Finding the mean of the total number ${N}_{\mathrm{tot}}$ of stationary points for $N$-dimensional random energy landscapes is reduced to averaging the absolute value of the characteristic polynomial of the corresponding Hessian. For any finite $N$ we provide the exact solution to the problem for a class of landscapes corresponding to the ``toy model'' of manifolds in a random environment. For $N\ensuremath{\gg}1$ our asymptotic analysis reveals a phase transition at some critical value ${\ensuremath{\mu}}_{c}$ of a control parameter $\ensuremath{\mu}$ from a phase with a finite landscape complexity: ${N}_{\mathrm{tot}}\ensuremath{\sim}{e}^{N\ensuremath{\Sigma}}$, $\ensuremath{\Sigma}(\ensuremath{\mu}l{\ensuremath{\mu}}_{c})g0$ to the phase with vanishing complexity: $\ensuremath{\Sigma}(\ensuremath{\mu}g{\ensuremath{\mu}}_{c})=0$. Finally, we discuss a method of dealing with the modulus of the spectral determinant applicable to a broad class of problems.

Twitter for teaching: Can social media be used to enhance the process of learning?

Abstract: Can social media be used to enhance the process of learning by students in higher education? Social media have become widely adopted by students in their personal lives. However, the application of social media to teaching and learning remains to be fully explored. In this study, the use of the social media tool Twitter for teaching was considered. Undergraduate students in Business and Management (n=252) were encouraged to use Twitter for communicating with their tutor and each other during a 12-week course. Their involvement was evaluated using a survey considering amount of Twitter usage and students' attitudes and experiences. The data were analysed using factor analyses, which revealed a single usage construct and three attitudinal factors. Three findings emerged. Firstly, a positive correlation was found between amount of Twitter usage and student engagement in university-associated activities including organising their social lives and sharing information. Secondly, course-related tweeting was not related to interpersonal relationships between students and their tutor. Thirdly, Twitter usage did not impact class attendance. The results are salient for educational practitioners wishing to introduce social media into their teaching. © 2013 British Educational Research Association.

An Event-Triggered Approach to State Estimation for a Class of Complex Networks With Mixed Time Delays and Nonlinearities

Abstract: In this paper, the state estimation problem is investigated for a class of discrete-time complex networks subject to nonlinearities, mixed delays, and stochastic noises. A set of event-based state estimators is constructed so as to reduce unnecessary data transmissions in the communication channel. Compared with the traditional state estimator whose measurement signal is received under a periodic clock-driven rule, the event-based estimator only updates the measurement information from the sensors when the prespecified “event” is violated. Attention is focused on the analysis and design problem of the event-based estimators for the addressed discrete-time complex networks such that the estimation error is exponentially bounded in mean square. A combination of the stochastic analysis approach and Lyapunov theory is employed to obtain sufficient conditions for ensuring the existence of the desired estimators and the upper bound of the estimation error is also derived. By using the convex optimization technique, the gain parameters of the desired estimators are provided in an explicit form. Finally, a simulation example is used to demonstrate the effectiveness of the proposed estimation strategy.

Immunodepression, high IgM levels and evasion of the immune response in murine trypanosomiasis.

Abstract: THERE is currently much interest in the devices evolved by parasites which enable them to evade the immune responses mounted by their hosts1. One such device is the phenomenon of antigenic variation associated with the salivarian trypano-some infections of man and animals in Africa2,3. Typically these infections show successive waves of blood parasitaemia. Each succeeding trypanosome population is characterised by a novel variant-specific glycoprotein antigen present in the parasite surface coat and not reactive with antibodies induced against preceding variants4,5. Antigenic variation has a clear role in the evasion of host immunity and leads to chronic and usually fatal infections. More recently we have become aware of a possible additional component of the evasion mechanism, generalised immunodepression.

Ill Effects: The Media Violence Debate

Abstract: Ill Effects is a radical re-examination of the whole 'media effects' debate. It questions not only whether the media is capable of directly influencing people's views and actions, but also whether the idea of 'effects' is the most useful way of conceptualising the relationship between the media and audiences. Ill Effects looks at the reasons why the media are routinely blamed for horrific events such as the murders of James Bulger and Suzanne Capper and the Hungerford massacre, as well as for perceived trends such as the alleged 'death of the family' and the rise of 'yob culture'. The authors' concern goes beyond individual cases: they discuss the development and current state of play of research into media effects, the remarkable power of 'common-sense' notions of media effects and the way in which the effects issue has become embroiled in debates about freedom of expression and censorship. They suggest how audiences really respond to media texts, and argue that there is an urgent need for informed and interdisciplinary approaches to the study of the media.