Overimitation may illuminate not only the structure of children’s causal understanding, but also the social learning processes that support our species’ artefact-centric culture.”
“Thermoplastic starch (TPS)/poly(vinyl alcohol) (PVA) blend films were modified by crosslinking through soaking the films in glutaraldehyde aqueous solution and then heating in an oven. The effects of the concentration of the glutaraldehyde aqueous solution, soaking time, reaction HM781-36B inhibitor temperature, and time on the crosslinking reaction were investigated. The moisture absorption and mechanical properties of the films were measured to characterize the influence of the crosslinking modification.

It was found that the crosslinking

modification significantly reduced the moisture sensitivity of the TPS/PVA blend films and increased the tensile strength and Young’s modulus but decreased the elongation at break of the TPS/PVA blend films. The described method could be used for posttreating TPS/PVA-based products to optimize their properties. (C) 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012″
“Operation of atmospheric discharge of electronegative gases including air at low voltages yet without consuming any inert gas will enormously promote the application of non-thermal plasmas. By taking advantage of the low onset voltage for helium corona, air discharge was successfully launched at much reduced voltages with a needle-plate system partly contained GSK1838705A Protein Tyrosine Kinase inhibitor in a helium-filled glass bulb-for a needle-plate distance of 12 mm, 1.0 kV suffices. Ultraviolet

emission from helium corona facilitates the discharging of air, and the discharge current selleckchem manifests distinct features such as relatively broad Trichel pulses in both half periods. This design allows safe and economic implementation of atmospheric discharge of electronegative gases, which will find a broad palette of applications in surface modification, plasma medicine and gas treatment, etc. (C) 2011 American Institute of Physics. [doi:10.1063/1.3651600]“
“This paper explores childhood social learning among Aka and Bofi hunter-gatherers in Central Africa. Existing literature suggests that hunter-gatherer social learning is primarily vertical (parent-to-child) and that teaching is rare. We use behavioural observations, open-ended and semi-structured interviews, and informal and anecdotal observations to examine the modes (e. g. vertical versus horizontal/oblique) and processes (e. g. teaching versus observation and imitation) of cultural transmission. Cultural and demographic contexts of social learning associated with the modes and processes of cultural transmission are described. Hunter-gatherer social learning occurred early, was relatively rapid, primarily vertical under age 5 and oblique and horizontal between the ages of 6 and 12.