Nonlinear Integrable Ion Traps

Quadrupole ion traps can be transformed into nonlinear traps with integrable motion by adding special electrostatic potentials. This can be done with both stationary potentials (electrostatic plus a uniform magnetic field) and with time-dependent electric potentials. These potentials are chosen such that the single particle Hamilton-Jacobi equations of motion are separable in some coordinate systems. The electrostatic potentials have several free adjustable parameters allowing for a quadrupole trap to be transformed into, for example, a double-well or a toroidal-well system. The particle motion remains regular, non-chaotic, integrable in quadratures, and stable for a wide range of parameters. We present two examples of how to realize such a system in case of a time-independent (the Penning trap) as well as a time-dependent (the Paul trap) configuration

Ring for test of nonlinear integrable optics

Nonlinear optics is a promising idea potentially opening the path towards achieving super high beam intensities in circular accelerators. Creation of a tune spread reaching 50% of the betatron tune would provide strong Landau damping and make the beam immune to instabilities. Recent theoretical work has identified a possible way to implement stable nonlinear optics by incorporating nonlinear focusing elements into a specially designed machine lattice. In this report we propose the design of a test accelerator for a proof-of-principle experiment. We discuss possible studies at the machine, requirements on the optics stability and sensitivity to imperfections.Comment: 3 pp. Particle Accelerator, 24th Conference (PAC'11) 28 Mar - 1 Apr 2011: New York, US

Project Retrosight. Understanding the returns from cardiovascular and stroke research: Policy Report

Copyright @ 2011 RAND Europe. All rights reserved. The full text article and the summary of the article are both available via the links below.This project explores the impacts arising from cardiovascular and stroke research funded 15-20 years ago and attempts to draw out aspects of the research, researcher or environment that are associated with high or low impact. The project is a case study-based review of 29 cardiovascular and stroke research grants, funded in Australia, Canada and UK between 1989 and 1993. The case studies focused on the individual grants but considered the development of the investigators and ideas involved in the research projects from initiation to the present day. Grants were selected through a stratified random selection approach that aimed to include both high- and low-impact grants. The key messages are as follows: 1) The cases reveal that a large and diverse range of impacts arose from the 29 grants studied. 2) There are variations between the impacts derived from basic biomedical and clinical research. 3) There is no correlation between knowledge production and wider impacts 4) The majority of economic impacts identified come from a minority of projects. 5) We identified factors that appear to be associated with high and low impact. This report presents the key observations of the study and an overview of the methods involved. It has been written for funders of biomedical and health research and health services, health researchers, and policy makers in those fields. It will also be of interest to those involved in research and impact evaluation.This study was initiated with internal funding from RAND Europe and HERG, with continuing funding from the UK National Institute for Health Research, the Canadian Institutes of Health Research, the Heart and Stroke Foundation of Canada and the National Heart Foundation of Australia. The UK Stroke Association and the British Heart Foundation provided support in kind through access to their archives

Recommandations based on empirical data : computer information and adaptive technologies in postsecondary education

Titre de départBibliogr.: p. 2

WWMM/CML Framework

Poster presented at the VSMF Symposium held at the Unilever Centre on 2011-01-17The World-Wide Molecular Matrix (2001-) is a design for capture and re-use of chemical information using Open semantic tools. There is no centre; scientists publish to the Matrix and re-use data from it. All data is Open. it interacts with the Linked Open Data Cloud

The Sexual Impact of Infertility Among Women Seeking Fertility Care.

IntroductionInfertility affects approximately 6.7 million women in the United States. Couples with infertility have significantly more anxiety, depression, and stress. This is compounded by the fact that almost 40% of couples undergoing assisted reproduction technology still cannot conceive, which can have an ongoing effect on quality of life, marital adjustment, and sexual impact.AimTo assess the sexual impact of infertility in women undergoing fertility treatment.MethodsThis study is a cross-sectional analysis of women in infertile couples seeking treatment at academic or private infertility clinics. Basic demographic information was collected. Respondents were surveyed regarding sexual impact and perception of their infertility etiology. Multivariate regression analyses were used to identify factors independently associated with increased sexual impact.Main outcome measureSexual impact of perceived fertility diagnosis.ResultsIn total, 809 women met the inclusion criteria, of whom 437 (54%) agreed to participate and 382 completed the sexual impact items. Most of the infertility was female factor only (58.8%), whereas 30.4% of infertility was a combination of male and female factors, 7.3% was male factor only, and 3.5% was unexplained infertility. In bivariate and multivariate analyses, women who perceived they had female factor only infertility reported greater sexual impact compared with woman with male factor infertility (P = .01). Respondents who were younger than 40 years experienced a significantly higher sexual impact than respondents older than 40 years (P < .01). When stratified by primary and secondary infertility, respondents with primary infertility overall reported higher sexual impact scores.ConclusionIn women seeking fertility treatment, younger age and female factor infertility were associated with increased sexual impact and thus these women are potentially at higher risk of sexual dysfunction. Providers should consider the role young age and an infertility diagnosis plays in a women's sexual well-being

Pluri-Canonical Models of Supersymmetric Curves

This paper is about pluri-canonical models of supersymmetric (susy) curves. Susy curves are generalisations of Riemann surfaces in the realm of super geometry. Their moduli space is a key object in supersymmetric string theory. We study the pluri-canonical models of a susy curve, and we make some considerations about Hilbert schemes and moduli spaces of susy curves.Comment: To appear in the proceedings of the intensive period "Perspectives in Lie Algebras", held at the CRM Ennio De Giorgi, Pisa, Italy, 201

Testing homogeneity with galaxy number counts : light-cone metric and general low-redshift expansion for a central observer in a matter dominated isotropic universe without cosmological constant

As an alternative to dark energy it has been suggested that we may be at the center of an inhomogeneous isotropic universe described by a Lemaitre-Tolman-Bondi (LTB) solution of Einstein's field equations. In order to test this hypothesis we calculate the general analytical formula to fifth order for the redshift spherical shell mass. Using the same analytical method we write the metric in the light-cone by introducing a gauge invariant quantity $G(z)$ which together with the luminosity distance $D_L(z)$ completely determine the light-cone geometry of a LTB model.Comment: 13 page

Half a million excess deaths in the Iraq war:Terms and conditions may apply

Hagopian et al. (2013) published a headline-grabbing estimate for the Iraq war of half a million excess deaths , i.e. deaths that would not have happened without the war. We reanalyse the data from the University Collaborative Iraq Mortality Study and refute their dramatic claim. The Hagopian et al. (2013) estimate has four main defects: i) most importantly, it conflates non-violent deaths with violent ones; ii) it fails to account for the stratified sampling design of the UCIMS; iii) it fully includes all reported deaths regardless of death certificate backing, even when respondents say they have a death certificate but cannot produce one when prompted; iv) it adds approximately 100,000 speculative deaths not supported by data. Thus, we reject the 500,000 estimate. Indeed, we find that the UCIMS data cannot even support a claim that the number of non-violent excess deaths in the Iraq war has been greater than zero. We recommend future research to follow our methodological lead in two main directions; supplement traditional excess death estimates with excess death estimates for non-violent deaths alone, and use differences-in-differences estimates to uncover the relationship between violence and non-violent death rates