OBJECTIVE To examine genetic and environmental contributions to stability and change in sleep problems (SP) in early childhood. METHODS The sample comprised over 300 twin pairs assessed at ages 2 and 3 years. Parents rated SP on the Sleep Problems subscale of the Child Behavior Checklist for ages 1.5-5 years. RESULTS Longitudinal quantitative genetic analyses indicated that SP were genetica...

BACKGROUND The Child Behavior Checklist-juvenile bipolar disorder phenotype (CBCL-JBD) is a quantitative phenotype that is based on parental ratings of the behavior of the child. The phenotype is predictive of DSM-IV characterizations of BD and has been shown to be sensitive and specific. Its genetic architecture differs from that for inattentive, aggressive, or anxious-depressed syndromes. The...

We examined developmental trends and sources of stability and change in adolescent personality by using twin data collected from 1981 to 2010 (273 monozygotic (MZ) and 48 dizygotic (DZ) twin pairs) from a secondary school affiliated with the University of Tokyo. Phenotypic analyses showed high rank-order stability and substantial mean-level increases in neuroticism and declines in extraversion ...

This paper studies the stochastic stability of genetic regulatory networks with intrinsic and extrinsic noises. A delay dependent stability condition with disturbance attenuation is derived for the stochastic genetic networks with time-varying delays. The developed criteria can be tested efficiently by Matlab LMI Control Toolbox. A numerical example with simulations is given to illustrate the e...

Languages vary in whether or not primary grammatical relations (PGRs) are sensitive to information from clause-level case or phrase structures. This variation correlates with a difference between verb agreement systems based on feature unification and systems based on feature composition. The choice between different PGR and agreement principles is found to be highly stable genetically and to c...

A committee of U.S. industry scientists from the Pharmaceutical Manufacturers Association has reviewed the recent suggestions of Galibert and Center for Biologics Evaluation and Research (CBER) regarding assurances of product consistency by cloning and sequencing efforts. We disagree that their proposals will achieve this goal, and estimate that such efforts will be very costly in terms of regu...

In this issue of Molecular Cell, Foit et al. (2009) probe cellular protein folding using a split beta-lactamase approach for evolving protein stability in the absence of any requirement for function.

Two factors that can lead to geographic structuring in conspecific populations are barriers to dispersal and climatic stability. Populations that occur in different physiographic regions may be restricted to those areas by physical and/or ecological barriers, which may facilitate the formation of phylogeographic clades. Long-term climatic stability can also promote genetic diversification, beca...

The study of the stability of -dimensional systems is a difficult one especially when 3. There exist only a few results in the literature and unfortunately, there does not exist any practical criterion. In this brief, the stability of an -dimensional system is dealt as a minimization problem of the absolute value of its characteristic polynomial over the boundaries of its variables (i.e., on th...

One very encouraging development has been the freedom with which amino acid replacements can be introduced in a protein of interest. This has made it possible to obtain detailed structural and thermodynamic data on a wide variety of mutants that modify protein stability. Substitutions of solvent-exposed amino acids on the surfaces of proteins are seen to have little if any effect on protein sta...