352 research outputs found

    Introduction to Q-tensor theory

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    This paper aims to provide an introduction to a basic form of the Q{\bf Q}-tensor approach to modelling liquid crystals, which has seen increased interest in recent years. The increase in interest in this type of modelling approach has been driven by investigations into the fundamental nature of defects and new applications of liquid crystals such as bistable displays and colloidal systems for which a description of defects and disorder is essential. The work in this paper is not new research, rather it is an introductory guide for anyone wishing to model a system using such a theory. A more complete mathematical description of this theory, including a description of flow effects, can be found in numerous sources but the books by Virga and Sonnet and Virga are recommended. More information can be obtained from the plethora of papers using such approaches, although a general introduction for the novice is lacking. The first few sections of this paper will detail the development of the Q{\bf Q}-tensor approach for nematic liquid crystalline systems and construct the free energy and governing equations for the mesoscopic dependent variables. A number of device surface treatments are considered and theoretical boundary conditions are specified for each instance. Finally, an example of a real device is demonstrated

    Infinite-dimensional statistical manifolds based on a balanced chart

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    We develop a family of infinite-dimensional Banach manifolds of measures on an abstract measurable space, employing charts that are balanced between the density and log-density functions. The manifolds, (Mλ,λ e [2,∞)), retain many of the features of finite-dimensional information geometry; in particular, the α-divergences are of class C[λ]-1, enabling the definition of the Fisher metric and α-derivatives of particular classes of vector fields. Manifolds of probability measures, (Mλ,λ e [2,∞)), based on centred versions of the charts are shown to be C[λ]-1-embedded submanifolds of the. Mλ. The Fisher metric is a pseudo-Riemannian metric on. Mλ. However, when restricted to finite-dimensional embedded submanifolds it becomes a Riemannian metric, allowing the full development of the geometry of α-covariant derivatives. Mλ and Mλ provide natural settings for the study and comparison of approximations to posterior distributions in problems of Bayesian estimation

    Graduates of Character - Values and Character: Higher Education and Graduate Employment

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    Graduates of Character is the product of an empirical enquiry into the values, virtues, dispositions and attitudes of a sample of students and employees who volunteered to be involved. The research team sought host sites which would offer a diverse set of interviewees in gender, ethnicity, religion and aspiration. In this study we discuss what character is taken to mean by students and employees in their years of higher education and employment. We examine what their values are, what they gain from the university, what they believe employers look for when recruiting, what they hope to give to an employer, and what they expect from their employer. We then explore who or what influenced their values and moral development. We also examined the role of the personal tutor or mentor, and the persons or services to which they might go for personal and/or professional support

    Adipokines as potential prognostic biomarkers in patients with acute knee injury

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    This review considers adipokines as predictive biomarkers for early onset post-traumatic knee osteoarthritis (KOA). Serum concentrations of leptin and resistin can predict radiographic changes and are elevated in early KOA, with higher leptin concentrations independently associated with more severe knee changes. Plasma concentrations of resistin are chronically elevated after injury. Leptin, resistin, chemerin and vistfatin induce catabolic enzymes associated with cartilage degeneration. Available literature on adipokines in post-traumatic KOA pathogenesis suggests that they could contribute to risk prediction of early onset post-traumatic KOA. Further research is needed to further understand the association between adipokines, synovitis and long-term outcomes in this population

    Transfer Entropy and Directed Information in Gaussian diffusion processes

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    Transfer Entropy and Directed Information are information-theoretic measures of the directional dependency between stochastic processes. Following the definitions of Schreiber and Massey in discrete time, we define and evaluate these measures for the components of multidimensional Gaussian diffusion processes. When the components are jointly Markov, the Transfer Entropy and Directed Information are both measures of influence according to a simple physical principle. More generally, the effect of other components has to be accounted for, and this can be achieved in more than one way. We propose two definitions, one of which preserves the properties of influence of the jointly Markov case. The Transfer Entropy and Directed Information are expressed in terms of the solutions of matrix Riccati equations, and so are easy to compute. The definition of continuous-time Directed Information we propose differs from that previously appearing in the literature. We argue that the latter is not strictly directional

    Mr Jones’ defence: a re-appraisal of the works of Henry Arthur Jones

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    Henry Arthur Jones (1851-1929) was a prolific English dramatist of the fin de siùcle. A contemporary of Wilde and Shaw, Jones at his peak had greater commercial success and critical acclaim as a playwright than either of them, but his reputation diminished rapidly after his death. The last book solely about Jones was published in 1932, and such critical attention as Jones has received since the mid-twentieth century has tended to be hostile: his plays about the Woman Question were received particularly badly by second-wave feminist commentators, and successive critics have perpetuated the assessment of Jones as typifying a certain kind of late-Victorian misogyny that hardly merits detailed analysis. However, signs have emerged of a revival of academic interest, with several of Jones’ individual plays being discussed in recent works about the theatrical representation of illicit female sexuality, Victorian perceptions of marriage, theatre and evolution, and the influence of John Ruskin. In this thesis, I undertake a broader reappraisal of Jones, by considering the writing and reception history of a selection of plays addressing important cultural themes – masculinities, religion, socialism, the Woman Question and imperialism – and demonstrate how Jones developed a subversive dramaturgical strategy that enabled him to articulate critique within the framework of ostensibly conventional narratives. This strategy was part of a wider reformist challenge that Jones undertook against the institutions of the theatre, particularly the actor-manager system and the censorship, championing the primacy of the dramatist. Although his input into debates about nation and theatre would manifest in increasingly pro-imperialist and pro-establishment ways in the latter part of his career, I conclude that Jones should be viewed as a significant figure in the development of the English stage, whose plays both reflect and critique the changing cultural landscape and social mores of fin de siùcle Britain

    Maximum work extraction and implementation costs for nonequilibrium Maxwell's demons

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    We determine the maximum amount of work extractable in finite time by a demon performing continuous measurements on a quadratic Hamiltonian system subjected to thermal fluctuations, in terms of the information extracted from the system. The maximum work demon is found to apply a high-gain continuous feedback involving a Kalman-Bucy estimate of the system state and operates in nonequilibrium. A simple and concrete electrical implementation of the feedback protocol is proposed, which allows for analytic expressions of the flows of energy, entropy, and information inside the demon. This let us show that any implementation of the demon must necessarily include an external power source, which we prove both from classical thermodynamics arguments and from a version of Landauer's memory erasure argument extended to nonequilibrium linear systems

    Strategically using public housing assets could transform our middle suburbs

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    ‘Greyfields’ in the Australian context have been defined as those ageing but occupied tracts of inner and middle ring suburbia that are physically, technologically and environmentally failing. The research sought to test the potential of an innovative design based approach to create coordinated precincts in these suburbs involving the coordinated redevelopment of multiple, non-contiguous public housing lots (rather than relying on the ‘default’ option of incremental market based development of in-fill housing and piecemeal selling off of public housing properties). Recent public housing investments (under the Social Housing Initiative) were typically planned with job creation in mind rather than innovative housing outcomes, but innovations were still apparent. Innovations were generally simple such as improvements to parking arrangements and interfaces of private dwellings with common areas and public spaces and arrangements for tenancy mix and social diversity. Innovations were often more apparent when governments partnered with Community Housing Organisations who could access alternative land and funding sources, offer design and delivery expertise and facilitate mixed tenancy outcomes. Innovation also was more likely when there was a ‘champion’ for design quality, relaxation of selected planning controls, and project alignment with existing urban renewal strategies. The Department of Human Services (Victorian Government) was found to have existing housing assets in sufficient number (more than 6500 DHS properties) in well-located areas of Melbourne’s middle suburbs that were clustered in ways broadly suitable for coordinated precinct redevelopment. Preliminary investigations suggest the same in Sydney and Brisbane. The coordinated precinct approach could offer an effective model for redeveloping dispersed public housing assets. Integrated redevelopment can achieve substantial increases in dwelling yield—design scenarios developed in this study delivered two to four times the number of dwellings when compared to business-as-usual dual occupancy outcomes. A precinct design approach is potentially more efficient because it allows for non-uniform, flexible siting of higher density buildings, effective program mixes, efficient parking arrangements and a variety of households and tenure types to be accommodated across a neighbourhood. Preliminary discussions with key stakeholders—municipal authorities, community housing organisations and local community members—showed real interest in the benefits of a coordinated precinct-based development approach. - See more at: http://www.ahuri.edu.au/publications/projects/p52012#sthash.wTtz4itu.dpu

    ‘Dyfodol llwyddiannus’ i bawb yng Nghymru? Yr heriau wrth ddiwygio cwricwla i ymdrin ag anghydraddoldeb addysgol

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    Mae’r papur hwn yn ymdrin ñ’r goblygiadau sydd yn y cwricwlwm trawsnewidiol myfyriwr‐ganolog sy’n cael ei ddatblygu yng Nghymru o ran delio ag anghydraddoldeb addysgol. Drwy roi sylw i ddadleuon sydd wedi parhau ers cyfnod hir ym maes cymdeithaseg addysg am y rhan sydd gan wybodaeth ysgol mewn atgynhyrchu cymdeithasol a diwylliannol, mae ein hymchwil yn amlinellu rhai o’r heriau sy’n wynebu’r rheini a fydd yn gweithredu’r Cwricwlwm i Gymru os yw i gynnig ‘dyfodol llwyddiannus’ i bawb. Gan wneud defnydd o ddata o gyfweliadau ac arolygon o’r ysgolion hynny sydd wedi ymgymryd ñ’r dasg o ddatblygu’r cwricwlwm newydd, a’r gwerthusiad o ddiwygio tebyg iawn ar y cwricwlwm ar gyfer addysg gynradd a’r blynyddoedd cynnar yng Nghymru, rydym yn amlinellu’r galwadau am adnoddau materol a dynol gan y cwricwlwm newydd a’r risgiau o gynyddu hyblygrwydd. Rydym yn dadlau y bydd angen buddsoddi sylweddol a rhyw fath o atebolrwydd allanol i sicrhau bod myfyrwyr dan anfantais yn cael profiad o’r cwricwlwm sy’n agor y ffordd at ‘wybodaeth bwerus’

    Whole body vibration exposure on markers of bone turnover, body composition, and physical functioning in breast cancer patients receiving aromatase inhibitor therapy: A randomized controlled trial

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    Introduction: Women with breast cancer are often prescribed aromatase inhibitors, which can cause rapid loss of bone mass leading to significant potential for morbidity. Vibration training has been shown to be helpful in reducing bone turnover in postmenopausal women without cancer. Aim: To examine the effect of vibration stimulus on markers of bone turnover in breast cancer patients receiving aromatase inhibitors. Methods: Thirty-one breast cancer survivors undergoing treatment with aromatase inhibitors were randomized to vibration stimulus (n = 14) or usual care control (n = 17). Low-frequency and low-magnitude vibration stimulus (27-32 Hz, 0.3g) was delivered in supervised sessions via standing on a vibration platform for 20 minutes, 3 times per week for 12 weeks. The primary outcome was blood markers of bone resorption (serum N-telopeptide X/creatine) and formation (serum type 1 procollagen N-terminal propeptide; P1NP). Other study outcomes body composition as well as measures of physical functioning. Outcomes were compared between groups using analysis of covariance adjusted for baseline values as well as time on aromatase inhibitors. Outcomes: On average, participants were 61.5 years old and overweight (ie, body mass index = 28.5 kg/m2). Following vibration training, there was no significant difference between groups for bone resorption (adjusted group difference 0.5, P = .929) or formation (adjusted group difference 5.3, P = .286). There were also no changes in any measure of physical functioning body composition. Conclusions: Short-term low-magnitude vibration stimulus does not appear to be useful for reducing markers of bone turnover secondary to aromatase inhibitors in breast cancer patients; nor is it useful in improving physical function or symptoms. However, further investigations with larger samples and higher doses of vibration are warranted. Trial Registration: Australian and New Zealand Clinical Trials Registry (ACTRN12611001094965)
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