Quantum steering ellipsoids, extremal physical states and monogamy

A Corrigendum for this article has been published in 2015 New J. Phys. 17 019501Any two-qubit state can be faithfully represented by a steering ellipsoid inside the Bloch sphere, but not every ellipsoid inside the Bloch sphere corresponds to a two-qubit state. We give necessary and sufficient conditions for when the geometric data describe a physical state and investigate maximal volume ellipsoids lying on the physical-unphysical boundary. We derive monogamy relations for steering that are strictly stronger than the Coffman-Kundu- Wootters (CKW) inequality for monogamy of concurrence. The CKW result is thus found to follow from the simple perspective of steering ellipsoid geometry. Remarkably, we can also use steering ellipsoids to derive non-trivial results in classical Euclidean geometry, extending Eulers inequality for the circumradius and inradius of a triangle.The EPSRC and the ARC Centre of Excellence grant no. CE110001027. DJ is funded by the Royal Society. TR would like to thank the Leverhulme Trust. SJ acknowledges EPSRC grant EP/ K022512/1

Factors influencing continuation and withdrawal from coaching youth football in metropolitan Western Australia

It is inevitable that at some stage of his career. a coach will withdraw. This qualitative study explored the various reasons why coaches of youth football (between the ages of 13 and 17 years) choose to continue or withdraw their involvement with the sport. It was the first part of a two phase larger study into this topic involving: (a) in depth interviews with current and former youth football coaches: and (b) the uses of themes from the interview data to develop a questionnaire for distribution to a larger sample of youth football coaches at a later stage. Perceptions and experiences of eight current and eight former youth football coaches from four of the six Western Australian Football Development Trust (WAFDT) metropolitan football regions formed the basis of this research through one-on-one, tape recorded interviews. Findings from this study revealed that there is a number of principle factors that influence a coach’s motivation to continue or withdraw. Youth football coach continuation will be assisted if the coach: (a) receives support from his wife and family: (b) values intrinsic rewards over extrinsic incentives: (c) embraces compulsory accreditation and its related benefits: and (d) does not allow his own son\u27s involvement as a player influence his own coaching. The youth football coach may be motivated to discontinue his involvement if: (a) he receives pressure from his family to spend more time with them: (b) be has lack of parent and player support and commitment; (c) he has a change in work commitments that do not allow the investment of the necessary time and effort required for coaching: (d) he has lack of time or inclination to complete the requirements of a compulsory Level I accreditation course: and (e) his son ceases his involvement as a player at the youth level

What makes or breaks a campaign to stop an invading plant pathogen?

Diseases in humans, animals and plants remain an important challenge in our society. Effective control of invasive pathogens often requires coordinated concerted action of a large group of stakeholders. Both epidemiological and human behavioural factors influence the outcome of a disease control campaign. In mathematical models that are frequently used to guide such campaigns, human behaviour is often ill-represented, if at all. Existing models of human, animal and plant disease that do incorporate participation or compliance are often driven by pay-offs or direct observations of the disease state. It is however very well known that opinion is an important driving factor of human decision making. Here we consider the case study of Citrus Huanglongbing disease (HLB), which is an acute bacterial disease that threatens the sustainability of citrus production across the world. We show how by coupling an epidemiological model of this invasive disease with an opinion dynamics model we are able to answer the question: What makes or breaks the effectiveness of a disease control campaign? Frequent contact between stakeholders and advisors is shown to increase the probability of successful control. More surprisingly, we show that informing stakeholders about the effectiveness of control methods is of much greater importance than prematurely increasing their perceptions of the risk of infection. We discuss the overarching consequences of this finding and the effect on human as well as plant disease epidemics

Frontal theta band oscillations predict error correction and posterror slowing in typing

Performance errors are associated with robust behavioral and electroencephalography (EEG) effects. However, there is a debate about the nature of the relationship between these effects and implicit versus explicit error awareness. Our aim was to study the relationship between error related electrophysiological effects, such as spectral perturbations in fronto-medial theta band oscillations (FMT), and error awareness in typing. Typing has an advantage as an experimental paradigm in that detected errors are quickly and habitually signaled by the participant using backspace, allowing separation of detected from undetected errors without interruption in behavior. Typing is thought to be controlled hierarchically via inner and outer loops, which rely on different sources for error detection. Touch-typist participants were asked to copy-type 100 sentences as EEG was recorded in the absence of visual feedback. Continuous EEG data were analyzed using independent component analysis (ICA). Time-frequency and ERP analyses were applied to emergent independent components. The results show that single-trial FMT parameters and error related negativity (ERN) amplitude predict overt, adaptive posterror actions such as error correction via backspace; and, posterror slowing, reflecting implicit error awareness. In addition, we found that those uncorrected errors which were slowed down the most were also the ones associated with a high level of FMT activity. Our results as a whole show that FMT are related to neural mechanisms involved in explicit awareness of errors, and input from inner loop is sufficient for error correction in typing. (PsycINFO Database Record (c) 2017 APA, all rights reserved

Impact of birth weight and gender on early postnatal hypothalamic energy balance regulatory gene expression in the young lamb

Peer reviewedPreprin

IC 4406: a radio-infrared view

IC 4406 is a large (about 100'' x 30'') southern bipolar planetary nebula, composed of two elongated lobes extending from a bright central region, where there is evidence for the presence of a large torus of gas and dust. We show new observations of this source performed with IRAC (Spitzer Space Telescope) and the Australia Telescope Compact Array. The radio maps show that the flux from the ionized gas is concentrated in the bright central region and originates in a clumpy structure previously observed in H_alpha, while in the infrared images filaments and clumps can be seen in the extended nebular envelope, the central region showing toroidal emission. Modeling of the infrared emission leads to the conclusion that several dust components are present in the nebula.Comment: 22 pages, 7 figures, accepted for publication in The Astrophysical Journal; v.2 has changes in both figures and content; preprint forma

L-functions with large analytic rank and abelian varieties with large algebraic rank over function fields

The goal of this paper is to explain how a simple but apparently new fact of linear algebra together with the cohomological interpretation of L-functions allows one to produce many examples of L-functions over function fields vanishing to high order at the center point of their functional equation. The main application is that for every prime p and every integer g>0 there are absolutely simple abelian varieties of dimension g over Fp(t) for which the BSD conjecture holds and which have arbitrarily large rank.Comment: To appear in Inventiones Mathematica

Two-dimensional soliton cellular automaton of deautonomized Toda-type

A deautonomized version of the two-dimensional Toda lattice equation is presented. Its ultra-discrete analogue and soliton solutions are also discussed.Comment: 11 pages, LaTeX fil

Cyborged ecosystems:Scenario planning and Participatory Technology Assessment of a potentially Rosennean-complex technology

Public involvement in technology policy making is particularly relevant because technological development is now reaching into virtually all planetary systems. The advent of Genetically Modified Organisms (GMO) for human food is particularly controversial, and it also raises questions about related technological-based potential products such as cyborged organisms in general. The research question in the present study is, what are the results of a Participatory Technology Assessment of cyborged ecosystems? The method utilized is Participatory Technology Assessment, implemented through scenario planning. The result of the study was three core themes: superfluous technology, dangerous tampering, and potential public health consequences. Resonances were observed between answers by laypersons and experts, indicating that they recognized the same issues but expressed themselves using different vocabularies and with different levels or types of understanding. Criteria are needed to ensure the public is able to engage in policy decisions that involve Rosennean-complex technologies