Child Effects on Parental Negativity: The Role of Heritable and Prenatal Factors

This study examined two possible mechanisms, evocative gene–environment correlation and prenatal factors, in accounting for child effects on parental negativity. Participants included 561 children adopted at birth, and their adoptive parents and birth parents within a prospective longitudinal adoption study. Findings indicated child effects on parental negativity, such that toddlers’ negative reactivity at 18 months was positively associated with adoptive parents’ over-reactive and hostile parenting at 27 months. Furthermore, we found that child effects on parental negativity were partially due to heritable (e.g., birth mother [BM] internalizing problems and substance use) and prenatal factors (e.g., BM illicit drug use during pregnancy) that influence children’s negative reactivity at 18 months. This study provides critical evidence for “child on parent” effects.     

The role of school leadership in Singapore's future-ready school reform

In this paper, we propose that successful education needs to fulfil three purposes while being cognisant of time and context: (a) learning, (b) lifework and (c) well-being. An education system is successful if it can develop future-ready individuals who will continue to learn beyond graduation, take on future lifework, and thrive in a changing society and environment. The future is context-situated and context-dependent. We have chosen to examine the economic, social and environmental context of Singapore to provide insight on the values, skills and knowledge that are required of future-ready learners according to the three purposes. We have compared the trajectories of other high-income nations with those of Singapore. Traditional teaching and learning practices no longer serve us well in the new realities that emerge. Education practices need to evolve in tandem to meet the demands of the 21st century. The roles that school leaders play include creating teaching and learning environments where these practices can be implemented. In our review of leadership practices and concepts, we have found that it is important for school leaders to question existing assumptions of teaching, learning and leadership practices in order to advance the development of 21st century skills, knowledge, values, and habits in learners.     

Concurrent validity of the early screening profiles and the differential ability scales with an at‐risk preschool sample

The relationship between the Early Screening Profiles (ESP; Harrison, 1990) and the Differential Ability Scales (DAS; Elliott, 1990a) was studied. The participants were 94 (57 males, 37 females) at‐risk preschoolers ranging in age from 3 years 6 months to 5 years 11 months (M= 4 years 7 months; SD= 6.3 months). The sample included 72 Caucasians, 21 African Americans, and one Hispanic. This study found that the DAS GCA (General Conceptual Ability) mean score was significantly lower than the ESP Total Screening mean score. However, a strong relationship (r= .78) was found between the ESP Total Screening and DAS GCA scores, indicating that the ESP is a good predictor of cognitive ability among at‐risk preschoolers. © 2000 John Wiley & Sons, Inc.     

Bifurcation analysis of a microcantilever in AFM system

The atomic force microscope system (AFM) has become a popular and useful instrument to measure the intermolecular forces with atomic resolution that can be applied in electronics, biological analysis, materials, semiconductors, etc. This paper studies the bifurcation phenomenon and complex nonlinear dynamic behavior of the probe tip between the sample and microcantilever of an atomic force microscope using the differential transformation method. The dynamic behavior of the probe tip is characterized with reference to bifurcation diagrams, phase portraits, power spectra, Poincaré maps, and maximum Lyapunov exponent plots produced using the time-series data obtained from differential transformation method. The results indicate that the probe tip behavior is significantly dependent on the magnitude of the vibrational amplitude. Specifically, the probe tip motion changes from T-periodic to 3T-periodic, then from 6T-periodic to multi-periodic, and finally to chaotic motion with windows of periodic motion as the vibrational amplitude is increased from 0 to 5.0. Furthermore, it is demonstrated that the differential transformation method is in good agreement for the considered system.     

Dinosaurs of a Feather

<正>From the earliest days of paleontological research, the origin of birds was an area of special interest. Largely thanks to the work of Thomas Huxley and the