Preliminary normative data on the BORB for children aged 3-8.

The Birmingham Object Recognition Battery (BORB) is a theoretically based test battery that is used in adult cognitive neuropsychology in research and for clinical assessment. It allows a detailed analysis of underlying impairments in individuals with brain injury who have visual object recognition difficulties. The BORB's usefulness in pediatrics is supported by numerous research studies. However, there is no published normative data for children, making clinical use of the test difficult. The aim of this brief report is to publish some preliminary normative data in 70 children aged between 3 and 8 years to assist both researchers and clinicians with interpretation of test scores. Results indicate that children's performance on individual BORB subtests varies according to task demands and age. For some subtests there is improvement in performance with increasing age. However, very young children (age 3-4 years) perform at adult levels on some subtests, or alternatively on other subtests they perform at the level of chance. The current paper supports the need for pediatric data for the BORB due to large normal individual variation in performance and varying age-related performance on individual BORB subtests.

Sandwich-lithiation and longitudinal crack in amorphous silicon coated on carbon nanofibers.

Silicon-carbon nanofibers coaxial sponge, with strong mechanical integrity and improved electronic conductivity, is a promising anode structure to apply into commercial high-capacity lithium ion batteries. We characterized the electrochemical and mechanical behaviors of amorphous silicon-coated carbon nanofibers (a-Si/CNFs) with in situ transmission electron microscopy (TEM). It was found that lithiation of the a-Si coating layer occurred from the surface and the a-Si/CNF interface concurrently, and propagated toward the center of the a-Si layer. Such a process leads to a sandwiched Li(x)Si/Si/Li(x)Si structure, indicating fast Li transport through the a-Si/CNF interface. Nanocracks and sponge-like structures developed in the a-Si layer during the lithiation-delithiation cycles. Lithiation of the a-Si layer sealed in the hollow CNF was also observed, but at a much lower speed than the counterpart of the a-Si layer coated on the CNF surface. An analytical solution of the stress field was formulated based on the continuum theory of finite deformation, explaining the experimental observation of longitudinal crack formation and general mechanical degradation mechanism in a-Si/CNF electrode.