Two-year-olds selectively seek help, but not based on helper maturity.

Help-seeking is a strategy by which children signal their need for social learning. In three experiments, we examined when and from whom 2-year-old (N = 146 children; mean age = 31.4 months) US children from diverse ethnoracial and economic backgrounds (62% White; 9% Latine; 24% low-income) seek help in problem-solving contexts.

Children's Selective Teaching and Informing: A Meta-Analysis.

Empirical studies on selective teaching and informing indicate that children may vary what they teach depending on whom they are teaching, taking into account how helpful the information is for a given audience. The current meta-analysis quantifies the effect of selective informing and teaching in 2-7-year-olds by examining the relationship between the helpfulness of the information and the frequency of information transmission. Through a systematic search that yielded 1483 results, 28 studies (104 effect sizes, N = 2716) met the inclusion criteria.

Use of a limited-channel device for obstructive sleep apnoea diagnosis in a tertiary sleep disorders centre.

Background: A major impediment to the provision of obstructive sleep apnoea (OSA) treatment is reliance on labour-intensive and costly laboratory-based polysomnography (PSG).

Aims: To investigate if measurement of oximetry and nasal flow through the ApneaLink device (AL) could identify patients with moderate-severe OSA among those referred for PSG to a tertiary sleep service.

Methods: New referrals to The Prince Charles Hospital Sleep Disorders Centre were assessed for suitability.

Oxidative mutagenicity of polar fractions from polycyclic aromatic hydrocarbon-contaminated soils.

Soils at hazardous waste sites contain complex mixtures of chemicals and often are difficult to characterize in terms of risk to human and ecological health. Over time, biogeochemical processes can decrease the apparent concentrations of pollutants but also can lead to accumulation of new products for which toxicity and behavior in the environment are largely unknown. A bioassay-directed fractionation technique was used to assess the contribution of redox-active bacterial metabolites to the toxicity of soil contaminated with polycyclic aromatic hydrocarbons (PAHs).