Neural Reuse and the Nature of Evolutionary Constraints

In humans, the reuse of neural structure is particularly pronounced at short, task-relevant timescales. Here, an argument is developed for the claim that facts about neural reuse at task-relevant timescales conflict with at least one characterization of neural reuse at an evolutionary timescale. It is then argued that, in order to resolve the conflict, we must conceptualize evolutionary-scale reuse more abstractly than has been generally recognized. The final section of the paper explores the relationship between neural reuse and human nature. It is argued that neural reuse is not well-described as a process that constrains our present cognitive capacities. Instead, it liberates those capacities from the ancestral tethers that might otherwise have constrained them

The Cognitive and Mathematical Profiles of Children in Early Elementary School

The present study investigated the diverse cognitive profiles of children learning mathematics in early elementary school. Unlike other types of learning difficulties, mathematics impairments are not characterized by a single underlying cognitive deficit, instead multiple general and numeracyspecific cognitive skills have been proposed to underlie mathematics ability. Combining theory- and data-driven approaches, the study investigated cognitive mathematics profiles. Participants for this study were 97 children tracked from senior kindergarten to grade two, as part of the Count Me In Study. Using numeracy, working memory, receptive language, and phonological awareness factors, a two-step cluster analysis revealed a three-cluster solution. The groups were characterized as (1) above average overall, (2) average overall with weak visuospatial working memory, (3) poor overall with strong visuospatial working memory. Cluster 1 demonstrated strengths in mathematics and reading, compared to clusters 2 and 3. Developmental trends and potential interventions are discussed

Tracer diffusion of boron in alpha-Ti and gamma-TiAl

Tracer diffusion of boron in pure alpha-Ti and gamma-TiAl (54 at.% A]) was measured by secondary ion mass spectroscopy using the stable B-11 isotope. The diffusion coefficients follow Arrhenius temperature dependencies with the frequency factors D-0 = 4.2 x 10(-6) and 2.48 x 10(-5) m(2) s(-1) and the activation enthalpies Q = 113 and 200 kJ mol(-1) for B diffusion in polycrystalline alpha-Ti and gamma-TiAl, respectively. Boron is a fast diffuser in both Ti and TiAl. The ratio of boron and titanium diffusivities is as large as 10(6)-10(7) in alpha-Ti and amounts to 10(3)-10(4) in gamma-TiAl. These results indicate a diffusion mechanism involving interstitial jumps. The relatively high activation enthalpy of B diffusion in gamma-TiAl is explained by the structure of the octahedral sites in the intermetallic compound

Tracer diffusion of boron in alpha-Ti and gamma-TiAl

Tracer diffusion of boron in pure alpha-Ti and gamma-TiAl (54 at.% A]) was measured by secondary ion mass spectroscopy using the stable B-11 isotope. The diffusion coefficients follow Arrhenius temperature dependencies with the frequency factors D-0 = 4.2 x 10(-6) and 2.48 x 10(-5) m(2) s(-1) and the activation enthalpies Q = 113 and 200 kJ mol(-1) for B diffusion in polycrystalline alpha-Ti and gamma-TiAl, respectively. Boron is a fast diffuser in both Ti and TiAl. The ratio of boron and titanium diffusivities is as large as 10(6)-10(7) in alpha-Ti and amounts to 10(3)-10(4) in gamma-TiAl. These results indicate a diffusion mechanism involving interstitial jumps. The relatively high activation enthalpy of B diffusion in gamma-TiAl is explained by the structure of the octahedral sites in the intermetallic compound

Smart Fabrication - Leistungsangepasste Hochtemperaturprozesse und Waferkonditionierungsverfahren Abschlussbericht

SIGLEAvailable from TIB Hannover: F01B931+a / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekBundesministerium fuer Bildung, Wissenschaft, Forschung und Technologie, Bonn (Germany)DEGerman