Press Release for the Thirteenth Annual John F. Sonnett Memorial Lecture Series: The Supreme Court of the United States

Press release for the Thirteenth Annual John F. Sonnett Memorial Lecture Series, The Supreme Court of the United States, given by William T. Coleman, partner at O\u27Melveny & Myers and former United States Secretary of Transportation (1975-1977).https://ir.lawnet.fordham.edu/events_programs_sonnett_miscellaneous/1017/thumbnail.jp

Can Frustration Preserve a Quasi-Two-Dimensional Spin Fluid?

Using spin-wave theory, we show that geometric frustration fails to preserve a two-dimensional spin fluid. Even though frustration can remove the interlayer coupling in the ground-state of a classical anti-ferromagnet, spin layers innevitably develop a quantum-mechanical coupling via the mechanism of ``order from disorder''. We show how the order from disorder coupling mechanism can be viewed as a result of magnon pair tunneling, a process closely analogous to pair tunneling in the Josephson effect. In the spin system, the Josephson coupling manifests itself as a a biquadratic spin coupling between layers, and for quantum spins, these coupling terms are as large as the inplane coupling. An alternative mechanism for decoupling spin layers occurs in classical XY models in which decoupled "sliding phases" of spin fluid can form in certain finely tuned conditions. Unfortunately, these finely tuned situations appear equally susceptible to the strong-coupling effects of quantum tunneling, forcing us to conclude that in general, geometric frustration cannot preserve a two-dimensional spin fluid.Comment: 12 pages, 3 figure

A question of scale

If you search for 'collective behaviour' with your web browser most of the texts popping up will be about group activities of humans, including riots, fashion and mass panic. Nevertheless, collective behaviour is also considered to be an important aspect of observed phenomena in atoms and molecules, for example, during spontaneous magnetization. In your web search, you might also find articles on collectively migrating bacteria, insects or birds; or phenomena where groups of organisms or non- living objects synchronize their signals or motion (think of fireflies flashing in unison or people clapping in phase during rhythmic applause).Comment: Concepts essay, published in Nature http://www.nature.com/nature/journal/v411/n6836/full/411421a0.htm

Qualitative study of pilot payment aimed at increasing general practitioners' antismoking advice to smokers

OBJECTIVES: To elicit general practitioners' and practice nurses' accounts of changes in their clinical practice or practice organisation made to claim a pilot health promotion payment. To describe attitudes towards the piloted and previous health promotion payments. DESIGN: Qualitative, semistructured interview study. SETTING: 13 general practices in Leicester. PARTICIPANTS: 18 general practitioners and 13 practice nurses. RESULTS: Health professionals did not report substantially changing their clinical practice to claim the new payments and made only minimal changes in practice organisation. The new health promotion payment did not overcome general practitioners' resistance towards raising the issue of smoking when they felt that doing so could cause confrontation with patients. General practitioners who made the largest number of claims altered the way in which they recorded patients' smoking status rather than raising the topic of smoking more frequently with patients. Participants had strong negative views on die new payment, feeling it would also be viewed negatively by patients. They were, however, more positive about health promotion payments that rewarded "extra" effort-for example, setting up practice based smoking cessation clinics. CONCLUSIONS: General practitioners and practice nurses were negative about a new health promotion payment, despite agreeing to pilot it. Health promotion payments do not automatically generate effective health promotion activity, and policymakers should consider careful piloting and evaluation of future changes in health promotion payments

Light pseudo-Goldstone bosons without explicit symmetry breaking

A mechanism is discussed to obtain light scalar fields from a spontaneously broken continuous symmetry without explicitly breaking it. If there is a continuous manifold of classical vacua in orbit space, its tangent directions describe classically massless fields that may acquire mass from perturbations of the potential that do not break the symmetry. We consider the simplest possible example, involving a scalar field in the adjoint representation of SU(N). We study the scalar mass spectrum and its RG running at one-loop level including scalar and pseudoscalar Yukawa couplings to a massive Dirac fermion.Comment: minor typographical changes, 12 pages, 4 figure

Prediction of stable walking for a toy that cannot stand

Previous experiments [M. J. Coleman and A. Ruina, Phys. Rev. Lett. 80, 3658 (1998)] showed that a gravity-powered toy with no control and which has no statically stable near-standing configurations can walk stably. We show here that a simple rigid-body statically-unstable mathematical model based loosely on the physical toy can predict stable limit-cycle walking motions. These calculations add to the repertoire of rigid-body mechanism behaviors as well as further implicating passive-dynamics as a possible contributor to stability of animal motions.Comment: Note: only corrections so far have been fixing typo's in these comments. 3 pages, 2 eps figures, uses epsf.tex, revtex.sty, amsfonts.sty, aps.sty, aps10.sty, prabib.sty; Accepted for publication in Phys. Rev. E. 4/9/2001 ; information about Andy Ruina's lab (including Coleman's, Garcia's and Ruina's other publications and associated video clips) can be found at: http://www.tam.cornell.edu/~ruina/hplab/index.html and more about Georg Bock's Simulation Group with whom Katja Mombaur is affiliated can be found at http://www.iwr.uni-heidelberg.de/~agboc

Magnetic quantum phase transition in an anisotropic Kondo lattice

The quantum phase transition between paramagnetic and antiferromagnetic phases of the Kondo lattice model with Ising anisotropy in the intersite exchange is studied within the framework of extended dynamical mean-field theory. Nonperturbative numerical solutions at zero temperature point to a continuous transition for both two- and three-dimensional magnetism. In the former case, the transition is associated with critical local physics, characterized by a vanishing Kondo scale and by an anomalous exponent in the dynamics close in value to that measured in heavy-fermion CeCu_{5.9}Au_{0.1}.Comment: 4 pages, 3 figures. Version published in Phys. Rev. Let

Predictors of postpartum return to smoking: a systematic review

Background Finding effective ways to help pregnant women quit smoking and remain abstinent is a major public health issue. Approximately half of UK women who smoke attempt cessation after conception; unfortunately, up to 75% return to smoking within 12 months postpartum. Interventions for preventing postpartum return to smoking (PPRS) have not been found to be effective. It is important to identify factors associated with PPRS, to inform development of alternative interventions. Aims Identify by systematic review factors associated with PPRS. Methods Systematic searches of electronic databases (MEDLINE, EMBASE, PsychINFO, CINAHL), trials registers and conference proceedings were conducted to November 2016. Studies statistically examining factors associated with PPRS were included. Modified versions of the Newcastle Ottawa Quality Assessment Scale were used to assess studies’ quality and a narrative synthesis focussed on those judged of high quality. Results Thirty-nine studies, (12 trials, 27 observational studies), were included. Thirty-one (79.5%) studies were high-quality. Among these, the most common significant predictors of PPRS were being less well educated, younger, multiparous, living with a partner or household member who smoked, experiencing higher stress, depression or anxiety, not breastfeeding, intending to quit only for pregnancy and low confidence to remain abstinent postpartum. Conclusions Of the factors found to be associated with PPRS, intending to quit smoking only for the duration of pregnancy, partner/household member smoking and confidence to remain abstinent are those most likely to have a direct, causal impact on smoking behaviour after childbirth, and need to be considered when designing interventions to prevent PPRS