8,372 research outputs found
First Year Computer Science Projects at Coventry University:Activity-led integrative team projects with continuous assessment.
We describe the group projects undertaken by first year undergraduate
Computer Science students at Coventry University. These are integrative course
projects: designed to bring together the topics from the various modules
students take, to apply them as a coherent whole. They follow an activity-led
approach, with students given a loose brief and a lot of freedom in how to
develop their project.
We outline the new regulations at Coventry University which eases the use of
such integrative projects. We then describe our continuous assessment approach:
where students earn a weekly mark by demonstrating progress to a teacher as an
open presentation to the class. It involves a degree of self and peer
assessment and allows for an assessment of group work that is both fair, and
seen to be fair. It builds attendance, self-study / continuous engagement
habits, public speaking / presentation skills, and rewards group members for
making meaningful individual contributions.Comment: 4 pages. Accepted for presentation at CEP2
Using Perturbative Least Action to Recover Cosmological Initial Conditions
We introduce a new method for generating initial conditions consistent with
highly nonlinear observations of density and velocity fields. Using a variant
of the Least Action method, called Perturbative Least Action (PLA), we show
that it is possible to generate several different sets of initial conditions,
each of which will satisfy a set of highly nonlinear observational constraints
at the present day. We then discuss a code written to test and apply this
method and present the results of several simulations.Comment: 24 pages, 6 postscript figures. Accepted for publication in
Astrophysical Journa
Do wildlife warning reflectors elicit aversion in captive macropods?
A goal to reduce the frequency of animal-vehicle collisions is motivating extensive research on this topic world-wide. Over the last 30 years, one popular mechanism to warn wildlife of approaching vehicles has been the wildlife warning reflector, manufactured and distributed under the brands Swareflex (Austria) and Strieter-Lite (USA). These reflectors were designed to scare deer and other ungulates from roadways at night by reflecting light from the headlights of approaching vehicles into the eyes of animals on the road verge. Robust documentation of their effectiveness has been lacking, yet there has been a push in Australia to examine their efficacy with regard to medium to large macropodids. Field trials of the reflectors are problematic and difficult to design rigorously, so we chose to examine the behavioural response of two captive macropodid species (Macropus rufus and M. rufogriseus) to the reflectors on a simulated road in order to derive some indication as to their efficacy. The behavioural response to the reflectors was negligible for both species and not consistent with an aversive effect to deter road use or crossing. We conclude that they would be of little value in our efforts to reduce the frequency of collisions of kangaroos or wallabies with vehicles in Australia. © CSIRO 2006
A systems and molecular analysis of G protein-mediated signalling
The ability of cells to respond correctly to signals from their microenvironment is an
essential prerequisite of life. Many external signals are detected through G protein-coupled
receptor (GPCR) signalling pathways, which control all aspects of eukaryotic physiology.
Ligand-bound GPCRs initiate signalling by promoting exchange of GDP for GTP on the
Gα subunit of heterotrimeric G proteins, thereby facilitating activation of downstream
effectors. Signalling is terminated by the hydrolysis of GTP to GDP through intrinsic
GTPase activity of the Gα subunit, in a reaction catalysed by the regulator of G protein
signalling (RGS) proteins.
Due to the problem of complexity in higher eukaryotic GPCR signalling, the matingresponse
in Schizosaccharomyces pombe has been used to study GPCR signalling in isolation.
In vivo data from quantitative assays of reporter strains and live-cell
uorescence
microscopy informs the development of an ordinary differential equation model of the signalling
pathway, first described by Smith et al., 2009.
The rate of nucleotide exchange on the Gα (Gpa1) is a key molecular mechanism controlling
duration and amplitude of signalling response. The in
uence of this is investigated
through characterisation of Gpa1 nucleotide exchange mutants and perturbation of reaction
rate parameters in the computational model. Further, this thesis also presents data
relating to the temporal and spatial regulation of Rgs1 (the sole RGS protein for Gpa1).
Using an inter-disciplinary approach, evidence is provided to suggest that an interaction
between Rgs1 and the C-terminal tail of the GPCR (Mam2) tethers Rgs1 to the plasma
membrane to facilitate its function.
Finally, quantification of signalling at the single cell level is described. Time-lapse livecell
imaging of
uorescent reporter cells is optimised and single cell signalling response
quantified using image analysis software. Single cell quantification provides greater insight
into temporal dynamics, cell-to-cell variability, and highlights the existence of mechanisms
for cellular decision-making
Predictive learning, prediction errors, and attention: evidence from event-related potentials and eye tracking
Prediction error (‘‘surprise’’) affects the rate of learning: We learn more rapidly about cues for which we initially make incorrect predictions than cues for which our initial predictions are correct. The current studies employ electrophysiological measures to reveal early attentional differentiation of events that differ in their previous involvement in errors of predictive judgment.
Error-related events attract more attention, as evidenced by features of event-related scalp potentials previously implicated in selective visual attention (selection negativity, augmented anterior N1). The earliest differences detected occurred around 120 msec after stimulus onset, and distributed source localization (LORETA)
indicated that the inferior temporal regions were one source of the earliest differences. In addition, stimuli associated with the production of prediction errors show higher dwell times in an eyetracking procedure. Our data support the view that early attentional processes play a role in human associative learning
Accuracy of the QUAD4 thick shell element
The accuracy of the relatively new QUAD4 thick shell element is assessed via comparison with a theoretical solution for thick homogeneous and honeycomb flat simply supported plates under the action of a uniform pressure load. The theoretical thick plate solution is based on the theory developed by Reissner and includes the effects of transverse shear flexibility which are not included in the thin plate solutions based on Kirchoff plate theory. In addition, the QUAD4 is assessed using a set of finite element test problems developed by the MacNeal-Schwendler Corp. (MSC). Comparison of the COSMIC QUAD4 element as well as those from MSC and Universal Analytics, Inc. (UAI) for these test problems is presented. The current COSMIC QUAD4 element is shown to have excellent comparison with both the theoretical solutions and also those from the two commercial versions of NASTRAN that it was compared to
Cultural selection drives the evolution of human communication systems
Human communication systems evolve culturally, but the evolutionary mechanisms that drive this evolution are not well understood. Against a baseline that communication variants spread in a population following neutral evolutionary dynamics (also known as drift models), we tested the role of two cultural selection models: coordination- and content-biased. We constructed a parametrized mixed probabilistic model of the spread of communicative variants in four 8-person laboratory micro-societies engaged in a simple communication game. We found that selectionist models, working in combination, explain the majority of the empirical data. The best-fitting parameter setting includes an egocentric bias and a content bias, suggesting that participants retained their own previously used communicative variants unless they encountered a superior (content-biased) variant, in which case it was adopted. This novel pattern of results suggests that (i) a theory of the cultural evolution of human communication systems must integrate selectionist models and (ii) human communication systems are functionally adaptive complex systems
Frequency and causes of kangaroo-vehicle collisions on an Australian outback highway
Kangaroo-vehicle collisions are frequent on Australian highways. Despite high economic costs, detrimental effects on animal welfare, and potential impacts on population viability, little research has been done to investigate the impact of road mortality on kangaroo populations, where and why accidents occur, and how the collisions can be mitigated. We therefore collected data on species (Macropus rufus, M. giganteus, M. fuliginosus, M. robustus), sex and age of kangaroos killed on a 21.2-km bitumenised section of outback highway over 6 months in far western New South Wales, Australia. The spatial and temporal distribution of road-killed kangaroos was investigated in relation to the cover and quality of road-side vegetation, road characteristics, the density of kangaroos along the road, climatic variables and traffic volume. A total of 125 kangaroos were found killed on the road at a rate of 0.03 deaths km-1 day-1. Grey kangaroos of two species (M. giganteus, M. fuliginosus) were under-represented in the road-kill sample in comparison with their proportion in the source population estimated during the day. No bias towards either sex was found. The age structure of road-killed kangaroos was similar to age structures typical of source kangaroo populations. Road-kills mainly occurred in open plains country. In road sections with curves or stock races, road-kill frequencies were higher than expected. Greater cover and greenness of roadside vegetation at the verge probably attracted kangaroos to the road and variation in this vegetation affected the spatial distribution of road-kills. The temporal distribution of road-kills was positively correlated with the volume of night-time traffic. The probability of a kangaroo-vehicle collision increased exponentially with traffic volume. Results are discussed in relation to the potential for mitigation of kangaroo-vehicle collisions. © CSIRO 2006
Contradiction and complacency shape attitudes towards the toll of roads on wildlife
© 2016 by the authors; licensee MDPI, Basel, Switzerland. Most people in the world now live in cities. Urbanisation simultaneously isolates people from nature and contributes to biodiversity decline. As cities expand, suburban development and the road infrastructure to support them widens their impact on wildlife. Even so, urban communities, especially those on the peri-urban fringe, endeavour to support biodiversity through wildlife friendly gardens, green spaces and corridors, and conservation estates. On one hand, many who live on city fringes do so because they enjoy proximity to nature, however, the ever increasing intrusion of roads leads to conflict with wildlife. Trauma (usually fatal) to wildlife and (usually emotional and financial) to people ensues. Exposure to this trauma, therefore, should inform attitudes towards wildlife vehicle collisions (WVC) and be linked to willingness to reduce risk of further WVC. While there is good anecdotal evidence for this response, competing priorities and better understanding of the likelihood of human injury or fatalities, as opposed to wildlife fatalities, may confound this trend. In this paper we sought to explore this relationship with a quantitative study of driver behaviour and attitudes to WVC from a cohort of residents and visitors who drive through a peri-urban reserve (Royal National Park) on the outskirts of Sydney, Australia. We distributed a self-reporting questionnaire and received responses from 105 local residents and 51 visitors to small townships accessed by roads through the national park. We sought the respondents’ exposure to WVC, their evasive actions in an impending WVC, their attitudes to wildlife fatalities, their strategies to reduce the risk of WVC, and their willingness to adopt new ameliorative measures. The results were partitioned by driver demographics and residency. Residents were generally well informed about mitigation strategies but exposure led to a decrease in viewing WVC as very serious. In addition, despite most respondents stating they routinely drive slower when collision risk is high (at dusk and dawn), our assessment of driving trends via traffic speeds suggested this sentiment was not generally adhered to. Thus we unveil some of the complexities in tackling driver’s willingness to act on reducing risk of WVC, particularly when risk of human trauma is low
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