Q: Why is a raven like a writing desk? A: They’re both objects

The famous riddle by Lewis Carroll is not really intended to have an answer, but rather to reveal the incomprehension Alice has of the world of adults. This paper is about a team of model-driven software engineers' concepts of "object" coming up against the building design sector's concept of "object", and challenging our assumptions about the clean and clever solutions that we can create with object-oriented metamodels and model transformation and code generation tools. However, the story has a happy ending in which the application of our tools in combination with pragmatic choices of representations of building designs still produces an outcome that meets our users' needs and avoids lots of bespoke programming

Attacking Group Protocols by Refuting Incorrect Inductive Conjectures

Automated tools for finding attacks on flawed security protocols often fail to deal adequately with group protocols. This is because the abstractions made to improve performance on fixed 2 or 3 party protocols either preclude the modelling of group protocols all together, or permit modelling only in a fixed scenario, which can prevent attacks from being discovered. This paper describes Coral, a tool for finding counterexamples to incorrect inductive conjectures, which we have used to model protocols for both group key agreement and group key management, without any restrictions on the scenario. We will show how we used Coral to discover 6 previously unknown attacks on 3 group protocols

KNEE SEPARATION DISTANCE AND QUADRICEPS AND HAMSTRINGS STRENGTH DURING DROP VERTICAL JUMP LANDINGS

Non-contact anterior cruciate ligament (ACL) injury is common particularly in female athletes during jump landing tasks. Ligament dominance occurs when the muscles cannot control knee movement sufficiently thus increasing medial knee motion. Preferential use of the quadriceps during landing and greater strength compared to the hamstrings also increase the load placed on the ACL (Dugan, 2005). Noyes et al. (2005) measured knee separation distance during jump landings finding an increase after neuromuscular training. The aim of this study was to examine the relationship between knee separation distance during drop jump landing and hamstrings and quadriceps strength in female athletes

The prevalence of smoking and the knowledge of smoking hazards and smoking cessation strategies among hiv positive patients in johannesburg, south africa

Background: While the detrimental effects of smoking among HIV positive patients have been well documented, there is a paucity of data regarding cigarette smoking prevalence among these patients in South Africa. Objectives: To establish the frequency, demographics, and knowledge of harmful effects and of smoking cessation strategies among HIV-positive patients in Johannesburg, South Africa. Methods: A prospective cross-sectional survey, using a structured questionnaire interview, of HIV-positive patients attending the HIV Clinic at the Charlotte Maxeke Johannesburg Academic Hospital between 1 July 2011 and 31 October 2011. Results: Of 207 HIV positive patients attending an ARV roll-out clinic, 31 (15%) were current smokers (23% of the males and 7.5% of the females) and a further 45 (21.7%) were ex-smokers. Most of the current smokers (30/31 patients) indicated their wish to quit smoking, and among the group as a whole most patients were aware of the general (82.5%) and HIV-related (77.8%) risks of smoking and of methods of quitting smoking. Despite this, however, most (61.8%) were not aware of whom they could approach for assistance and advice. Conclusions: Given the relatively high prevalence of current and ex-smokers amongst HIV positive patients there is a need for the introduction of smoking cessation strategies and assistance at HIV-rollout clinics in South Africa

Classical and quantum regimes of two-dimensional turbulence in trapped Bose-Einstein condensates

We investigate two-dimensional turbulence in finite-temperature trapped Bose-Einstein condensates within damped Gross-Pitaevskii theory. Turbulence is produced via circular motion of a Gaussian potential barrier stirring the condensate. We systematically explore a range of stirring parameters and identify three regimes, characterized by the injection of distinct quantum vortex structures into the condensate: (A) periodic vortex dipole injection, (B) irregular injection of a mixture of vortex dipoles and co-rotating vortex clusters, and (C) continuous injection of oblique solitons that decay into vortex dipoles. Spectral analysis of the kinetic energy associated with vortices reveals that regime (B) can intermittently exhibit a Kolmogorov $k^{-5/3}$ power law over almost a decade of length or wavenumber ($k$) scales. The kinetic energy spectrum of regime (C) exhibits a clear $k^{-3/2}$ power law associated with an inertial range for weak-wave turbulence, and a $k^{-7/2}$ power law for high wavenumbers. We thus identify distinct regimes of forcing for generating either two-dimensional quantum turbulence or classical weak-wave turbulence that may be realizable experimentally.Comment: 11 pages, 10 figures. Minor updates to text and figures 1, 2 and

Permissive Controller Synthesis for Probabilistic Systems

We propose novel controller synthesis techniques for probabilistic systems modelled using stochastic two-player games: one player acts as a controller, the second represents its environment, and probability is used to capture uncertainty arising due to, for example, unreliable sensors or faulty system components. Our aim is to generate robust controllers that are resilient to unexpected system changes at runtime, and flexible enough to be adapted if additional constraints need to be imposed. We develop a permissive controller synthesis framework, which generates multi-strategies for the controller, offering a choice of control actions to take at each time step. We formalise the notion of permissivity using penalties, which are incurred each time a possible control action is disallowed by a multi-strategy. Permissive controller synthesis aims to generate a multi-strategy that minimises these penalties, whilst guaranteeing the satisfaction of a specified system property. We establish several key results about the optimality of multi-strategies and the complexity of synthesising them. Then, we develop methods to perform permissive controller synthesis using mixed integer linear programming and illustrate their effectiveness on a selection of case studies

Coherent spin control by electromagnetic vacuum fluctuations

In coherent control, electromagnetic vacuum fluctuations usually cause coherence loss through irreversible spontaneous emission. However, since the dissipation via emission is essentially due to correlation of the fluctuations, when emission ends in a superposition of multiple final states, correlation between different pathways may build up if the "which-way" information is not fully resolved (i.e., the emission spectrum is broader than the transition energy range). Such correlation can be exploited for spin-flip control in a $\Lambda$-type three-level system, which manifests itself as an all-optical spin echo in nonlinear optics with two orders of optical fields saved as compared with stimulated Raman processes. This finding represents a new class of optical nonlinearity induced by electromagnetic vacuum fluctuations.Comment: 7 pages including 5 figure

Do women who consult with naturopaths or herbalists have a healthy lifestyle?: a secondary analysis of the Australian longitudinal study on women's health.

BACKGROUND:Australians report consulting with a naturopaths or herbalists to improve their wellbeing, yet little is known about the associations between these consultations and the patients' health behaviours. This cross-sectional study aimed to examine the relationship between health behaviour and consultations with naturopaths or herbalists in three age cohorts of Australian women. METHODS:Women aged 19-25 years, 31-36 years, and 62-67 years from the Australian Longitudinal Study on Women's Health (ALSWH) were surveyed regarding smoking, alcohol or drug use, physical activity and dietary behaviour; and whether they consulted with naturopath/herbalists in the last 12 months. Associations were analysed using multivariable logistic regression. RESULTS:A total of 9151 (19-25 years), 8200 (31-36 years) and 11,344 (62-67 years) women were included in the analysis. Between 7.3 and 11.9% of women reported to have consulted with naturopaths/herbalists in the last 12 months. Women of all cohorts consulting with naturopath/herbalist were less likely to smoke (19-25 yrs.: Odds Ratio [OR] 0.61; 31-36 years: OR 0.58; 62-67 years: OR 0.29), more likely to report at least moderate levels of physical activity (19-25 yrs.: OR 1.41; 31-36 years: OR 1.34; 62-67 years: OR 1.34), and the use of vegetarian diets(19-25 yrs.: OR 1.40; 31-36 years: OR 1.77; 62-67 years: OR 2.28), compared to women not consulting with naturopaths/herbalists. Women consulting with naturopaths/herbalists however were also more likely to have used marijuana (19-25 yrs.: OR 1.18; 31-36 years: OR 1.42), or illicit drugs in the last 12 months (19-25 yrs.: OR 1.24; 31-36 years: OR 1.40). CONCLUSIONS:Consultations with a naturopath or herbalist are associated with positive health behaviours that are protective of internationally important non-communicable diseases. Psychoactive drug use is also reported among women visiting a naturopath or herbalist. Further research is needed to understand the role naturopaths play in advising patients with regards to health and non-healthy behaviours

Non-equilibrium dynamics: Studies of reflection of Bose-Einstein condensates

The study of the non-equilibrium dynamics in Bose-Einstein condensed gases has been dominated by the zero-temperature, mean field Gross-Pitaevskii formalism. Motivated by recent experiments on the reflection of condensates from silicon surfaces, we revisit the so-called {\em classical field} description of condensate dynamics, which incorporates the effects of quantum noise and can also be generalized to include thermal effects. The noise is included in a stochastic manner through the initial conditions. We show that the inclusion of such noise is important in the quantitative description of the recent reflection experiments