Applied Nonlinear Stochastic Dynamics

Abstract

This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at Los Alamos National Laboratory (LANL). This is a fundamental research project whose aim is exploiting the last decades' progress in understanding the dynamics of nonlinear andor noisy systems in applications to a variety of problems in theoretical physics, chemistry and biology. The common denominator here is the fundamental role played by the combination of nonlinearity, noise and/or disorder in the dynamics of both simple and complex systems, and the underlying theoretical problems have much in common within the paradigms of nonlinear science. This project extends a technology base relevant to a variety of problems arising in applications of nonlinearity in science, and applies this technology to those problems. Thus, numerical simulations and experiments focused on nonlinear and stochastic processes provide important insights into nonlinear science, while nonlinear techniques help advance our understanding of the scientific principles underlying the control of complex behavior in systems with strong spatial and temporal internal variability.

Decoupling of the Magnetic and Structural Transformations inEr5Si4

“…1). X-ray powder diffraction data confirm that the crystal structure of Er 5 Si 4 remains unchanged across 30 K in magnetic fields up to 35 kOe [22]. Therefore, the major difference between all previously known monoclinic R 5 Si 4ÿx Ge x compounds and the Er 5 Si 4 phase is that magnetic and crystallographic lattices remain decoupled in the latter.…”

Returning a Research Participant's Genomic Results to Relatives: Analysis and Recommendations

“…Although traditionally returning genetic results of child participants has been limited to those that are actionable during childhood, 70 recent recommendations recognize that a child's research results may have significant, actionable implications for the child's parents. 71 The law also provides parent/guardians with significant power over the health information of their children. 72 Although law and societal norms generally defer to parental authority in decision making regarding a child's health and welfare, 73 parents and guardians should strongly consider the interests and expressed wishes of the child in deciding whether to share the child's genomic information with relatives.…”

“…Holm and colleagues have taken an initial position that their project will not return results when parents and adolescents disagree, though they will examine each case, expect their approach to evolve, and would nonetheless return results that "predict[] imminent risks of severe harm that can be prevented only by disclosure." 81 Those authors were considering return of results to participants, so the issue was potential harm or benefit to the adolescent. We focus here instead on return of a participant's results to relatives; the issue is the potential intrusion on the child's privacy and other interests versus potential benefit to relatives.…”

Novel Coincidence Techniques, Detectors and Concepts for Safety, Security and Safeguards

“…Another neutron detector concept recently investigated at STUK is a portable capture-gated neutron spectrometer [2]. The detector is a cylindrical 3 × 3 borated plastic scintillator -EJ254 with 5% natural boron by weight, Eljen Technology.…”