From ugly duckling to swan?: Japanese and American beliefs about the stability and origins of traits

Two studies compared the development of beliefs about the stability and origins of physical and psychological traits in Japan and the United States in three age groups: 5–6-year-olds, 8–10-year-olds, and college students. The youngest children in both cultures were the most optimistic about negative traits changing in a positive direction over development and being maintained over the aging period. The belief that individual differences in traits are inborn increased with age, and in all age groups, this belief was related to predictions of greater trait stability. In both cultures, all ages believed positive traits would be maintained over development. In addition to developmental similarities across cultures, cultural variations, consistent with the hypothesis that interdependent cultures have a more incremental view of traits, were present. Japanese participants were more optimistic than American participants about negative traits changing towards the positive and were more likely to attribute differences in trait expression to effort.     

3D shape and orientation of nanoscale Pb inclusions at grain boundaries in Al observed by TEM and STEM tomography

We have combined high-angle annular dark field/scanning transmission electron microscopy (HAADF-STEM) tomography with bright field (BF)-TEM tomography to characterize small inclusions of Pb at a grain boundary in Al. It was found that the shape of the grain boundary inclusions is more complex than previously thought. By using moiré fringes observed at some orientations of the specimen in a BF-TEM tomographic tilt series, we were able to determine the orientation of each grain, the axis and angle of misorientation of the grain boundary, and the facet planes of the grain boundary inclusions. The 3D shape of the inclusions was determined by merging this information with the HAADF-STEM tomography.     

Spatiotemporal dynamics of long-term potentiation in rat insular cortex revealed by optical imaging

Long-term potentiation (LTP) of the gustatory cortex (GC), a part of the insular cortex (IC) around the middle cerebral artery, is a key process of gustatory learning and memory, including conditioned taste aversion learning. The rostral (rGC) and caudal GC (cGC) process different tastes; the rGC responds to hedonic and the cGC responds to aversive tastes. However, plastic changes of spatial interaction of excitatory propagation between the rGC and cGC remain unknown. The present study aimed to elucidate spatiotemporal profiles of excitatory propagation, induced by electrical stimulation (five train pulses) of the rGC/cGC before and after LTP induction, using in vivo optical imaging with a voltage-sensitive dye. We demonstrated that tetanic stimulation of the cGC induced long-lasting expansion of the excitation responding to five train stimulation of the cGC, and an increase in amplitude of optical signals in the IC. Excitatory propagation after LTP induction spread preferentially toward the rostral IC: the length constant (λ) of excitation, obtained by fitting optical signals with a monoexponential curve, was increased to 121.9% in the rostral direction, whereas λ for the caudal, dorsal, and ventral directions were 48.9%, 44.2%, and 62.5%, respectively. LTP induction was prevented by pre-application of D-APV, an NMDA receptor antagonist, or atropine, a muscarinic receptor antagonist, to the cortical surface. In contrast, rGC stimulation induced only slight LTP without direction preference. Considering the different roles of the rGC and cGC in gustatory processing, these characteristic patterns of LTP in the GC may be involved in a mechanism underlying conversion of palatability.