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991.
An inverse “smaller is stronger” trend is predicted on the basis of molecular dynamics simulations of α-titanium (Ti) single-crystal nanopillars orientated for double prismatic slips when the nanopillars are less than 7?nm wide. This trend is attributed to a significant increase in the surface energy due to the nucleation and propagation of edge dislocations on the surface of the pillars. 相似文献
992.
Koichi Mikami 《Science as culture》2013,22(2):183-204
AbstractRegenerative medicine (RM) in Japan lays strong emphasis on a specific trajectory of its development, which deploys human induced pluripotent stem (iPS) cells as the primary sources for the technology. The technique to create these stem cells was developed in 2006 by a Japanese stem cell scientist, Shinya Yamanaka, and since its applicability to human cells was established about a year later, this new type of cells has become to be considered as a potential substitute for human embryonic stem cells. While the clinical value of these cells are yet to be confirmed, the Japanese Ministry of Education, Culture, Sports, Science and Technology decided to concentrate its support on iPS cells research and turned it into a national project. This decision reflected the state's vision of initiating the transition to a knowledge-based society, which was adopted in the 1990s to tackle the prolonged deflation in the country. As the research became intertwined with this policy vision, however, the Ministry came to see bringing its success as more important than ever, while other trajectories of RM were left underrated and largely unsupported. Industrial actors counteracted this situation and developed an initiative to recognize existing technical capability in the country, but its impact has been so far negligible. This indicates that the nation is locked in the particular trajectory of RM. Hence, this Japanese RM research enterprise presents an interesting case to understand how states' commitment may not only shape the course of scientific research but also reduce flexibility in technological development. 相似文献
993.
In this study, 63 observations of secular IQ changes (both Flynn and anti-Flynn effects) are collected from three demographically diverse studies of the Dutch population for the period 1975–2005 (representing the 1950–1990 birth cohorts), along with data on g loadings and subtest reliabilities. The method of correlated vectors is used to explore the association between Flynn and anti-Flynn effect magnitudes, both independently and together, and the g loadings of subtests. Despite a positive vector correlation the Flynn effects are not associated with the Jensen effect (r = .307, ns, N = 36), however the anti-Flynn effects are (r = .406, P = .05, N = 27). Combined, the vector correlation becomes negative but non-significant (r = −.111, ns, N = 63). Declines due to the anti-Flynn effect are estimated at −4.515 points per decade, whereas gains due to the Flynn effect are estimated at 2.175 points per decade. The N-weighted net of these is a loss of −1.350 points per decade, suggesting an overall tendency towards decreasing IQ in the Netherlands with respect to these cohorts. The Jensen effect on the anti-Flynn effect suggests that it may be related to bio-demographic changes within the Netherlands which have reduced ‘genetic-g’, despite the presence of large, parallel gains on subtests that may be relatively more sensitive to cultural-environmental improvements. 相似文献
994.
The relationship between the Flynn effect and ability differentiation is investigated in a reanalysis of published data on Estonian student cohorts tested in 1933/36, 1997/98 and 2006 on the National Intelligence Test (Must, te Nijenhuis, Must, & van Vianen, 2009). To determine whether there was a relationship we computed the vector correlation between the Flynn effects (d) and the change in the g loading (Δg) between measurement occasions for each of the 10 NIT subtests and for each of the seven cohort comparisons, giving a total N of 70 effect sizes. The association between d and Δg was robustly negative (indicating that the Flynn effects were negatively associated with changes in the g loading of subtests) for all cohort comparisons, with values of r ranging from −.100 to −.461 (N = 10). When all effect sizes were analyzed together, the vector correlation was found to be −.281 (p ? .05, N = 70). This indicates a significant association between the Flynn effect and ability differentiation. Possible causes of this association are discussed. 相似文献
995.
In this study we attempt to determine whether dysgenic fertility is associated with the Jensen effect. This is investigated with respect to a US population representative sample of 8110 individuals from the National Longitudinal Survey of Youth for whom there exists complete data on IQ and fertility. In addition to the general sample, the sample was also broken out by race and sex so as to examine whether or not the Jensen effect manifested amongst different sub-populations. The method of correlated vectors revealed significant Jensen effects in five of the seven samples, and in all cases the effect was in a direction indicating that subtests with higher g-loadings were associated with larger dysgenic fertility gradients. The magnitude of the difference between Spearman’s ρ and Pearson’s r was non-significant in all cases, suggesting that biasing factors were minimally influencing the result. This finding suggests that dysgenesis occurs on the ‘genetic g’ at the heart of the Jensen effect nexus, unlike the Flynn effect, which is ‘hollow’ with respect to g. Finally, the finding is discussed in the context of two converging lines of evidence indicating that genotypic IQ or ‘genetic g’ really has been declining over the last century. 相似文献
996.
and r–K life history theory that Mongoloids are the most K evolved, Caucasoids somewhat less K evolved, and Negroids the least K evolved is examined and extended in an analysis of data for erect penis length and circumference in two new data sets. These new data extend Rushton’s theory by presenting disaggregated data for penis size for European and North African/South Asian Caucasoids; for East Asian and Southeast Asian Mongoloids; for Inuit and Amerindians and Mestizos, and for thirteen mixed race samples. The results generally confirm and extend Rushton’s r–K life history theory. 相似文献
997.
998.
Adolescents move to evening orientation just when school schedule becomes earlier. Whereas school achievement has been associated to morningness orientation during morning school schedule, some studies have indicated that evening people are more intelligent. In this study the relative contribution of Morningness–Eveningness (M–E) in the prediction of school achievement, after controlling for age, sex/gender, inductive reasoning and sleep length was analyzed. Participants were 887 adolescents (aged 12–16). School achievement was evaluated using Grade Point Average (GPA), inductive reasoning was evaluated by reasoning subtest of Primary Mental Abilities (PMA-R), sleep length was calculated from rise time and bedtime questions, and M–E was evaluated by Morningness–Eveningness Scale for Children (MESC). Evening adolescents scored higher on PMA-R and obtained lower GPA. Inductive reasoning, age, sex/gender, sleep length and M–E accounted for 19% variance percentage on GPA. M–E was a significant predictor of school achievement even after controlling for traditional predictors, albeit slightly. 相似文献
999.
Association between maternal sensitivity and externalizing behavior from preschool to preadolescence
Feihong Wang Sharon L. Christ W. Roger Mills-Koonce Patricia Garrett-Peters Martha J. Cox 《Journal of applied developmental psychology》2013
Using data from the longitudinal NICHD Study of Early Child Care and Youth Development (N = 1364), this study examined the association between mothers' sensitivity and children's externalizing behavior from preschool to preadolescence. Externalizing behavior declined on average across this period with a slowing of this decline around middle childhood. Maternal sensitivity remained relatively stable on average, and there was significant variation across mothers. A decrease in maternal sensitivity from ages 3 to 11 was related to an increase in externalizing behavior from ages 4 to 12. A model-based test of the direction of the effect suggested that the association between changes in maternal sensitivity and externalizing behavior from ages 4 to 11 was driven by child effects on mothers and not vice-versa. Between late preschool age and preadolescence, the behavior problems of children appear to strongly influence the sensitive support of mothers. Practical implications were discussed in light of these findings. 相似文献
1000.
Blending phenomenological and evolutionary approaches, three studies explored the relationship between the body, the self, and disgust. Study 1 demonstrated that body parts that interface with the environment are sensed more than internal body parts, and are more intimately associated with the self. Studies 2 and 3, exploring the bodily distribution of disgust via organ transplantation scenarios, revealed that (a) transplantation of interface body parts is more disgusting than transplantation of internal parts; (b) others' interface parts elicit greater disgust than others' internal parts; and (c) individual differences in disgust sensitivity manifest primarily in reasoning about interface parts. The outer/inner dichotomy is a fundamental feature of the relationship between body and self, reflecting the adaptive utility of concentrating attention on the interface with the environment. Correspondingly, disgust, the emotion that protects the organism from contamination, is focused on the intersection between the body and the environment. 相似文献