Building macroscale models from microscale probabilistic models : a general probabilistic approach for nonlinear diffusion and multispecies phenomena

A discrete agent-based model on a periodic lattice of arbitrary dimension is considered. Agents move to nearest-neighbor sites by a motility mechanism accounting for general interactions, which may include volume exclusion. The partial differential equation describing the average occupancy of the agent population is derived systematically. A diffusion equation arises for all types of interactions and is nonlinear except for the simplest interactions. In addition, multiple species of interacting subpopulations give rise to an advection-diffusion equation for each subpopulation. This work extends and generalizes previous specific results, providing a construction method for determining the transport coefficients in terms of a single conditional transition probability, which depends on the occupancy of sites in an influence region. These coefficients characterize the diffusion of agents in a crowded environment in biological and physical processes.

The forgotten ones : a case study on conceptualising and implementing a peer mentoring program for postgraduate coursework students

We employed an action research approach to develop a context specific peer mentoring program (Postgrad Assist) that aids first year postgraduate coursework (PGCW) students in their transition to postgraduate study. We explored the transition literature and best practice approaches, undertook comprehensive surveys of both our students and staff, conducted student focus groups, formed a diverse working party, with strong representation from students and adopted an on-going evaluation program to develop and refine Postgrad Assist. The program substantially alleviated transitioning students’ cultural and academic shock, and social isolation. The program makes a contribution to the transition and mentoring research domain in that it challenges the common misconception that PGCW students are similar to undergraduate students with no particular distinguishing features that would suggest a need for a different approach to their mentoring.

Stop-signal task difficulty and the right inferior frontal gyrus

The stop-signal paradigm is increasingly being used as a probe of response inhibition in basic and clinical neuroimaging research. The critical feature of this task is that a cued response is countermanded by a secondary ‘stop-signal’ stimulus offset from the first by a ‘stop-signal delay’. Here we explored the role of task difficulty in the stop-signal task with the hypothesis that what is critical for successful inhibition is the time available for stopping, that we define as the difference between stop-signal onset and the expected response time (approximated by reaction time from previous trial). We also used functional magnetic resonance imaging (fMRI) to examine how the time available for stopping affects activity in the putative right inferior frontal gyrus and presupplementary motor area (right IFG-preSMA) network that is known to support stopping. While undergoing fMRI scanning, participants performed a stop-signal variant where the time available for stopping was kept approximately constant across participants, which enabled us to compare how the time available for stopping affected stop-signal task difficulty both within and between subjects. Importantly, all behavioural and neuroimaging data were consistent with previous findings. We found that the time available for stopping distinguished successful from unsuccessful inhibition trials, was independent of stop-signal delay, and affected successful inhibition depending upon individual SSRT. We also found that right IFG and adjacent anterior insula were more strongly activated during more difficult stopping. These findings may have critical implications for stop-signal studies that compare different patient or other groups using fixed stop-signal delays.

Brain networks subserving the evaluation of static and dynamic facial expressions

Because moving depictions of face emotion have greater ecological validity than their static counterparts, it has been suggested that still photographs may not engage ‘authentic’ mechanisms used to recognize facial expressions in everyday life. To date, however, no neuroimaging studies have adequately addressed the question of whether the processing of static and dynamic expressions rely upon different brain substrates. To address this, we performed an functional magnetic resonance imaging (fMRI) experiment wherein participants made emotional expression discrimination and Sex discrimination judgements to static and moving face images. Compared to Sex discrimination, Emotion discrimination was associated with widespread increased activation in regions of occipito-temporal, parietal and frontal cortex. These regions were activated both by moving and by static emotional stimuli, indicating a general role in the interpretation of emotion. However, portions of the inferior frontal gyri and supplementary/pre-supplementary motor area showed task by motion interaction. These regions were most active during emotion judgements to static faces. Our results demonstrate a common neural substrate for recognizing static and moving facial expressions, but suggest a role for the inferior frontal gyrus in supporting simulation processes that are invoked more strongly to disambiguate static emotional cues.

Stop-signal response inhibition in schizophrenia : Behavioural, event-related potential and functional neuroimaging data

Inhibitory control deficits are well documented in schizophrenia, supported by impairment in an established measure of response inhibition, the stop-signal reaction time (SSRT). We investigated the neural basis of this impairment by comparing schizophrenia patients and controls matched for age, sex and education on behavioural, functional magnetic resonance imaging (fMRI) and event-related potential (ERP) indices of stop-signal task performance. Compared to controls, patients exhibited slower SSRT and reduced right inferior frontal gyrus (rIFG) activation, but rIFG activation correlated with SSRT in both groups. Go stimulus and stop-signal ERP components (N1/P3) were smaller in patients, but the peak latencies of stop-signal N1 and P3 were also delayed in patients, indicating impairment early in stop-signal processing. Additionally, response-locked lateralised readiness potentials indicated response preparation was prolonged in patients. An inability to engage rIFG may predicate slowed inhibition in patients, however multiple spatiotemporal irregularities in the networks underpinning stop-signal task performance may contribute to this deficit.

The effect of sleep deprivation on BOLD activity elicited by a divided attention task

Sleep loss, widespread in today’s society and associated with a number of clinical conditions, has a detrimental effect on a variety of cognitive domains including attention. This study examined the sequelae of sleep deprivation upon BOLD fMRI activation during divided attention. Twelve healthy males completed two randomized sessions; one after 27 h of sleep deprivation and one after a normal night of sleep. During each session, BOLD fMRI was measured while subjects completed a cross-modal divided attention task (visual and auditory). After normal sleep, increased BOLD activation was observed bilaterally in the superior frontal gyrus and the inferior parietal lobe during divided attention performance. Subjects reported feeling significantly more sleepy in the sleep deprivation session, and there was a trend towards poorer divided attention task performance. Sleep deprivation led to a down regulation of activation in the left superior frontal gyrus, possibly reflecting an attenuation of top-down control mechanisms on the attentional system. These findings have implications for understanding the neural correlates of divided attention and the neurofunctional changes that occur in individuals who are sleep deprived.

Conservation communication camp : come with ideas, leave with a plan

IUCN´s core work involves generating knowledge and tools to influence policy and practice for nature conservation. Whilst it appears that we are collectively making progress in some areas, we acknowledge the need to improve our communication processes and practices to ´move to action´ in this regard. We need to extend the influence of the science and the knowledge beyond the documents to achieve effective impact and action. The training course will focus on the process of getting the conservation messages out to a wider audience. This interactive and participatory training course will develop the skills and knowledge needed to communicate effective conservation messages for a range of IUCN internal and external audiences. The course will cover: • what is communication for conservation? • the communication planning process (developing your communication objectives) • identifying and understanding your target audiences • developing your conservation message • choosing your communication media and • evaluating the effectiveness of your communication strategies. A unique feature of the training course will be the use of Web 2.0 tools in innovative conservation communications e.g. use of social media in concept branding and social marketing. In the spirit of the Forum´s objective of ´Sharing know how´, each participant will bring a current conservation issue to the training course and will leave with their own communication plan. Potentially, the training course adopts a cross-thematic approach as the issues addressed could be drawn from any of the IUCN´s program themes. Primarily though, the training course´s best fit is with the ´Valuing and Conserving Biodiversity´ theme since it will provide concrete and pragmatic solutions to enhancing the implementation of conservation measures through participatory planning and capacity building.

Pacific Neighbours : Understanding the Pacific Islands

Pacific Neighbours: Understanding the Pacific Islands (2009) is a resource book to develop understanding of the region, its history and geography, its political and social development, and its people and their cultures. The accompanying CD-ROM contains PDFs of the book, a reformatted version of the book by country using an interactive map, and extra teacher and student resources.

You are now entering the Twittersphere! Where EE meets social media

“Humans did not weave web 2.0, they are merely a strand in it. Whatever they do to the interweb, they do to themselves.” Is social media just a diversionary gimmick? A passing phase? The latest craze? Or can social media be socially ‘transformative’ media with an integral place in EE pedagogies? In this paper I will examine the affordances of Web 2.0 (and 3.0) technologies, such as social media, in the light of differences in perceptions of what technology represents underpinned by comparative theories of technology. An instrumental theory (or neutralist approach) of technology is one which views technology as a ‘tool’ without any inherent value whereas a critical theory of technology views technology as a site of struggle, of power relationships and of social transformation. From a critical perspective Web 2.0 (and 3.0) technologies have the capacity to democratise the knowledge economy by turning knowledge consumers into “prod-users” (Bruns, 2008); to promote ubiquitous learning; and to facilitate collaboration through online Communities of Practice. However, applying a critical technology perspective means that we also need to consider that web technologies are not a panacea: misappropriation and indiscriminate use of technology; substitution for valid EE experiences; environmental impacts; and exacerbating the digital divide are the flip side of the coin (W. J. Rohwedder, 1999).

Are we there yet? Early education responding to the challenges of climate disruption and sustainability

We are now in ‘The Critical Decade’ (Steffen & Hughes, 2013) when the world’s peoples must make strong choices if we are to avert the worst impacts of climate disruption. Yet, addressing climate disruption, challenging though this is, is not humanity’s biggest problem – rather, climate disruption is a symptom of unsustainable development models that depend on continuous economic growth that shape how we live.