Children with autism spectrum disorder (ASD) attend typically to faces and objects presented within their picture communication systems

ackground Children with autism spectrum disorder (ASD) may require interventions for communication difficulties. One type of intervention is picture communication symbols which are proposed to improve comprehension of linguistic input for children with ASD. However, atypical attention to faces and objects is widely reported across the autism spectrum for several types of stimuli. Method In this study we used eye-tracking methodology to explore fixation duration and time taken to fixate on the object and face areas within picture communication symbols. Twenty-one children with ASD were compared with typically developing matched groups. Results Children with ASD were shown to have similar fixation patterns on face and object areas compared with typically developing matched groups. Conclusions It is proposed that children with ASD attend to the images in a manner that does not differentiate them from typically developing individuals. Therefore children with and without autism have the same opportunity to encode the available information. We discuss what this may imply for interventions using picture symbols

Knowledge and barriers to inclusion of ASC pupils in Scottish mainstream schools:A mixed methods approach

Inclusion of autistic pupils into mainstream schools is common practice and staff should have adequate knowledge on teaching and managing classroom behaviour. However, autism knowledge among teaching staff may be inconsistent. A mixed-methods design examined differences between school staff in autism knowledge, perceived barriers to inclusion and required support. 138 early years staff, school teachers and pupil support assistants took part. Knowledge and experience were assessed using Knowledge about Childhood Autism among Health Workers questionnaire (KCAHW; [Bakare, M. O., P. O. Ebigbo, A. O. Agomoh, and N. C. Menkiti. 2008. Knowledge about childhood autism among health workers (KCAHW) questionnaire: description, reliability and internal consistency. Clinical Practice and Epidemiology in Mental Health 4 (1): 17]). Qualitative measures addressed perceived barriers to inclusion and recommended supports. Significant differences in the knowledge of autism scores were shown. Similar themes were identified across all staff, with five themes reflecting barriers to inclusion (Knowledge, Support, Training, Management of ASC features and Parent involvement) and four themes relating to required support (Individualising educational experience, Changes to learning spaces, Opportunities to learn about ASC and Communication). Government inclusion policy should take a whole school approach and consider staffs’ actual and perceived barriers to inclusion of autistic children

Evidence for variation in the effective population size of animal mitochondrial DNA

Background: It has recently been shown that levels of diversity in mitochondrial DNA are remarkably constant across animals of diverse census population sizes and ecologies, which has led to the suggestion that the effective population of mitochondrial DNA may be relatively constant. Results: Here we present several lines of evidence that suggest, to the contrary, that the effective population size of mtDNA does vary, and that the variation can be substantial. First, we show that levels of mitochondrial and nuclear diversity are correlated within all groups of animals we surveyed. Second, we show that the effectiveness of selection on non-synonymous mutations, as measured by the ratio of the numbers of non-synonymous and synonymous polymorphisms, is negatively correlated to levels of mitochondrial diversity. Finally, we estimate the effective population size of mitochondrial DNA in selected mammalian groups and show that it varies by at least an order of magnitude. Conclusions: We conclude that there is variation in the effective population size of mitochondria. Furthermore we suggest that the relative constancy of DNA diversity may be due to a negative correlation between the effective population size and the mutation rate per generation

Finite-size scaling of the error threshold transition in finite population

The error threshold transition in a stochastic (i.e. finite population) version of the quasispecies model of molecular evolution is studied using finite-size scaling. For the single-sharp-peak replication landscape, the deterministic model exhibits a first-order transition at $Q=Q_c=1/a$, where $Q$ is the probability of exact replication of a molecule of length $L \to \infty$, and $a$ is the selective advantage of the master string. For sufficiently large population size, $N$, we show that in the critical region the characteristic time for the vanishing of the master strings from the population is described very well by the scaling assumption \tau = N^{1/2} f_a \left [ \left (Q - Q_c) N^{1/2} \right ] , where $f_a$ is an $a$-dependent scaling function.Comment: 8 pages, 3 ps figures. submitted to J. Phys.

Error Thresholds on Dynamic Fittness-Landscapes

In this paper we investigate error-thresholds on dynamics fitness-landscapes. We show that there exists both lower and an upper threshold, representing limits to the copying fidelity of simple replicators. The lower bound can be expressed as a correction term to the error-threshold present on a static landscape. The upper error-threshold is a new limit that only exists on dynamic fitness-landscapes. We also show that for long genomes on highly dynamic fitness-landscapes there exists a lower bound on the selection pressure needed to enable effective selection of genomes with superior fitness independent of mutation rates, i.e., there are distinct limits to the evolutionary parameters in dynamic environments.Comment: 5 page

Elucidating the aetiology of human Campylobacter coli infections

Peer reviewedPublisher PD