We report frequency-locked resonant patterns induced by additive noise in periodically forced reaction-diffusion Brusselator model. In the regime of 2:1 frequency-locking and homogeneous oscillation, the introduction of additive noise, which is colored in time and white in space, generates and sustains resonant patterns of hexagons, stripes, and labyrinths which oscillate at half of the forcing...

We demonstrate that demographic noise can induce persistent spatial pattern formation and temporal oscillations in the Levin-Segel predator-prey model for plankton-herbivore population dynamics. Although the model exhibits a Turing instability in mean-field theory, demographic noise greatly enlarges the region of parameter space where pattern formation occurs. To distinguish between patterns ge...

This study investigated the immediate impact of an 8-month center- and home-based prevention program for preschoolers at high risk for conduct problems. We report immediate program effects on observed and self-rated parenting practices and observed child behavior with peers. Ninety-nine preschool-age siblings of adjudicated youths and their families were randomly assigned to an enhanced version...

X iv :p hy si cs /9 90 30 15 v2 [ ph ys ic s. cl as sph ] 2 4 A ug 1 99 9 Unified Expressions Of All Integral Variational Principles Based On The Quantitative Causal Principle Y. C. Huang 1,2 A. M. Li M. X. Shao X. G. Li Department of Applied Physics, Beijing Polytechnic University, Beijing 100022, P. R. China ( Email address: [email protected] ) Institute of Theoretical Physics, Chinese Acad...

Many models have been proposed for spatial pattern formation in embryology and analyzed for the standard case of zero-flux boundary conditions. However, relatively little attention has been paid to the role of boundary conditions on the form of the final pattern. Here we investigate numerically, the effect of nonstandard boundary conditions on a model pattern generator, which we choose to be of...

BACKGROUND Similar to lipid emulsion propofol, microemulsion propofol also causes a high incidence of pain during intravenous injection. Various methods have been used to minimize the incidence and severity of pain on injection of lipid emulsion propofol. In this study, we investigated the effect of a lidocaine mixture on pain induced by microemulsion propofol injection, and sought to determine...

An extremely large body of theoretical work exists on pattern formation, but very few experimental results have confirmed the relevance of theoretical models. It is argued in this article that the notion of agent-based pattern formation, which is introduced and exemplified, can serve as a basis to study pattern formation in nature, especially because pattern-forming systems based on agents are ...

Over time, developmental theories and empirical studies have gradually started to adopt a bidirectional viewpoint. The area of intervention research is, however, lagging behind in this respect. This longitudinal study examined whether bidirectional associations between (changes in) parenting and (changes in) aggressive child behavior over time differed in three conditions: a child intervention ...

The study examined the effects of conducting observations as part of a broader assessment of families participating in behavior family intervention (BFI). It was designed to investigate whether the observations improve intervention outcomes. Families were randomly assigned to different levels of BFI or a waitlist control condition and subsequently randomly assigned to either observation or no-o...

BACKGROUND We designed this double-blind, placebo-controlled study to compare the efficacy of remifentanil in reducing the pain of both propofol and rocuronium injection during rapid-sequence induction. METHODS Ninety-five patients, scheduled for elective surgery under general anesthesia, were divided into 3 groups: saline (Group S, n = 31), remifentanil 1 µg/kg (Group R, n = 32), and lidocai...