Probe-level microarray data are usually stored in matrices. Take a given probe set (gene), for example, each row of the matrix corresponds to an array, and each column corresponds to a probe. Often, people summarize each array by the gene expression level. Is one number sufficient to summarize a whole probe set for a specific gene in an array?…

Reinforcers contingent on response variability exert powerful and precise control over levels of variability, from stereotypy to stochasticity. This paper reviews how variability-contingent reinforcers interact with non-contingent, eliciting events to influence the variability of operant responses. Relationships to stimulus control, choice,…

This is a Pittsburgh story. It is about a boy named Michael Charles Metil--a boy that transformed many lives, including the author's. While visiting grandparents over the Christmas holiday in Latrobe, Pennsylvania in 1993, Michael became sick. He was lethargic, vomiting, and had some diarrhea. Little did his parents realize how very sick he was,…

A role for the Notch signalling pathway in the formation of arteriovenous malformations during development has been suggested. However, whether Notch signalling is involved in brain arteriovenous malformations in humans remains unclear. Here, we performed immunohistochemistry on surgically resected brain arteriovenous malformations and found that,…

This report used a population-representative longitudinal twin study with two birth cohorts to explore the association between intelligence and education by understanding how genetic and environmental influences on intelligence moderate genetic and environmental influences on school grades and educational attainment. Nonshared environmental…

It has been hypothesised that auditory processing may be enhanced in autism spectrum disorders (ASD). We tested auditory discrimination ability in 72 adolescents with ASD (39 childhood autism; 33 other ASD) and 57 IQ and age-matched controls, assessing their capacity for successful discrimination of the frequency, intensity and duration…

The male-to-female (M:F) ratio for autism spectrum disorders (ASD), typically about 4:1, appears to decrease with increasing paternal age, but this relationship has not been systematically tested. With 393 ASD cases from families with two or more ASD cases, we categorized paternal age into five age groups (less than 30, 30-34, 35-39, 40-44, 45+)…

We have devised and implemented a module for an upper division undergraduate laboratory based on the amplification and analysis of a p53 polymorphism associated with cancer susceptibility. First, students collected a drop of peripheral blood cells using a sterile sting and then used FTA cards to extract the genomic DNA. The p53 region is then PCR…

The study of selective attention and its influence on communication in patients with Rett Syndrome (RS), in which communication abilities are impaired is particularly relevant. The aim of this study was to analyse attention and communication abilities in RS. A sample of 20 children (10 girls with RS and 10 control girls, matched on mental age)…

This article traces the personal as well as the intellectual and scientific relationship between Charles Darwin and his younger half-cousin Francis Galton. Although they had been on friendly terms as young men, and Darwin had in some ways been a role model for Galton, the two did not share major scientific interests until after the publication of…

The neuro-developmental disorders of Williams syndrome (WS) and autism can reveal key components of social cognition. Eye-tracking techniques were applied in two tasks exploring attention to pictures containing faces. Images were (i) scrambled pictures containing faces or (ii) pictures of scenes with embedded faces. Compared to individuals who…

Although children with Williams syndrome have relatively good structural language and concrete vocabulary abilities, they have difficulty with pragmatic aspects of language. To investigate the impact of pragmatic difficulties on listener-role referential communication, we administered a picture placement task designed to measure ability to…

A seven-week "gene to protein" laboratory sequence is described for an undergraduate biochemistry laboratory course. Student pairs were given the task of introducing a point mutation of their choosing into the well studied protein, enhanced green fluorescent protein (EGFP). After conducting literature searches, each student group chose the…

Aversion to eye contact is a common behavior of individuals diagnosed with Fragile X syndrome (FXS); however, no studies to date have attempted to increase eye-contact duration in these individuals. In this study, we employed a percentile reinforcement schedule with and without overcorrection to shape eye-contact duration of 6 boys with FXS.…

As a parent of a son with an autism spectrum disorder (ASD), the author was aware of the various theories regarding genetic predictors, toxic and heavy metal exposure, and immunization after-effects. However, she had not seriously considered that genetics or a history of emotional and psychological challenges in her family line could have been…