Characterization of hexabundles: Initial results

New multi-core imaging fibre bundles -- hexabundles -- being developed at the University of Sydney will provide simultaneous integral field spectroscopy for hundreds of celestial sources across a wide angular field. These are a natural progression from the use of single fibres in existing galaxy surveys. Hexabundles will allow us to address fundamental questions in astronomy without the biases introduced by a fixed entrance aperture. We have begun to consider instrument concepts that exploit hundreds of hexabundles over the widest possible field of view. To this end, we have compared the performance of a 61-core fully-fused hexabundle and 5 lightly-fused bundles with 7 cores each. All fibres in the bundles have 100 micron cores. In the fully-fused bundle, the cores are distorted from a circular shape in order to achieve a higher fill fraction. The lightly-fused bundles have circular cores and five different cladding thicknesses which affect the fill fraction. We compare the optical performance of all 6 bundles and find that the advantage of smaller interstitial holes (higher fill fraction) is outweighed by the increase in modal coupling, cross-talk and the poor optical performance caused by the deformation of the fibre cores. Uniformly high throughput and low cross-talk are essential for imaging faint astronomical targets with sufficient resolution to disentangle the dynamical structure. Devices already under development will have between 100 and 200 lightly-fused cores, although larger formats are feasible. The light-weight packaging of hexabundles is sufficiently flexible to allow existing robotic positioners to make use of them.Comment: Accepted for publication in MNRAS. See also a complimentary paper on the development of hexabundles - Bland-Hawthorn et al. 2011, Optics Express, vol. 19, p. 2649 (http://www.opticsinfobase.org/abstract.cfm?URI=oe-19-3-2649

A Data Base System Designed for Flexibility and Usability from FORTRAN ; CU-CS-072-75

This paper discusses the design, implementation and usefulness of a system for the flexible creation, accessing, and reformatting of list structured data bases in ANSI FORTRAN programs. The system is portrayed as being a useful tool in building prototype systems where frequent design modifications are expected and which, for reasons such as portability, are to be written in FORTRAN

A FORTRAN System for Flexible Creation and Accessing of Data Bases ; CU-CS-052-74

This paper discusses the implementation of a data base management system designed to enable easy, flexible, data access from FORTRAN programs. The system was created in response to the need for a library of routines for accessing an archival data base whose structure is only tentative and is expected to change frequently and perhaps radically. A FORTRAN library interface between user programs and data bases is described. A methodology for conveniently restructuring data bases without having to change the FORTRAN programs accessing the data bases is presented. This paper also describes a system for restoring and then accessing a data base which has been saved in an obsolete format without having to alter any of the data accessing programs

Can voicing conflict within experiential learning groups facilitate connection? : Building and developing effective multi-disciplinary team-working skills

This is an Accepted Manuscript of an article published by Taylor & Francis in Reflective Practice on 24 November 2016, available online at: http://dx.doi.org/10.1080/14623943.2016.1251408. Under embargo. Embargo end date: 24 May 2018.In the UK, Clinical Psychologists (CPs) work in a variety of settings within the National Health Service (NHS), often within Multi-Disciplinary Teams (MDTs). Problem-Based Learning (PBL) within CP training at the University of Hertfordshire (UH) offers unique opportunities to combine scientist-practitioner and reflective-practitioner models to learn about group dynamics from the personal experience of working within an experiential learning group. Further, given Trainees work three days per week on placement within MDTs in the NHS, the learning gained within a ‘safer’ PBL context can be utilised within these clinical settings. For two years, Trainees at UH have to work in small PBL groups with five or six members learning to work together to achieve a goal (four assessed presentations) negotiating their own personal and professional journey, as well as a group journey. Consequently, PBL offers trainees opportunities to learn (1) how individuals work within a group; (2) how personal experiences influence this process; (3) how others influence them and are influenced by them; and (4) how a group of diverse individuals conceptualise, understand and convey case vignettes to an audience. Within these groups, many Trainees learn to speak out, reflect, listen attentively, empathise, validate and accept diverse experiences. Further, when differences dominate they often learn to negotiate these, finding a way to maintain effective team working in order to complete the presentation. Focusing on the conflict that can occur within (any) group, this paper explores themes from the reflective narratives of six trainees: parallels and differences between MDTs and PBL groups, striving for and achieving authenticity; and conflict as a ‘swear’ word. We conclude that exploring the role PBL can play in training individuals to work effectively in teams may be of benefit within the training of other professional groups.Peer reviewedFinal Accepted Versio

Convergence towards a European strategic culture? A constructivist framework for explaining changing norms.

The article contributes to the debate about the emergence of a European strategic culture to underpin a European Security and Defence Policy. Noting both conceptual and empirical weaknesses in the literature, the article disaggregates the concept of strategic culture and focuses on four types of norms concerning the means and ends for the use of force. The study argues that national strategic cultures are less resistant to change than commonly thought and that they have been subject to three types of learning pressures since 1989: changing threat perceptions, institutional socialization, and mediatized crisis learning. The combined effect of these mechanisms would be a process of convergence with regard to strategic norms prevalent in current EU countries. If the outlined hypotheses can be substantiated by further research the implications for ESDP are positive, especially if the EU acts cautiously in those cases which involve norms that are not yet sufficiently shared across countries

Kinetics of antigen expression and epitope presentation during virus infection

Current knowledge about the dynamics of antigen presentation to T cells during viral infection is very poor despite being of fundamental importance to our understanding of anti-viral immunity. Here we use an advanced mass spectrometry method to simultaneously quantify the presentation of eight vaccinia virus peptide-MHC complexes (epitopes) on infected cells and the amounts of their source antigens at multiple times after infection. The results show a startling 1000-fold range in abundance as well as strikingly different kinetics across the epitopes monitored. The tight correlation between onset of protein expression and epitope display for most antigens provides the strongest support to date that antigen presentation is largely linked to translation and not later degradation of antigens. Finally, we show a complete disconnect between the epitope abundance and immunodominance hierarchy of these eight epitopes. This study highlights the complexity of viral antigen presentation by the host and demonstrates the weakness of simple models that assume total protein levels are directly linked to epitope presentation and immunogenicity.NHMRC (National Health and Medical Research Council of Australia

Genetics Ignite Focus on Microglial Inflammation in Alzheimer\u27s Disease

In the past five years, a series of large-scale genetic studies have revealed novel risk factors for Alzheimer\u27s disease (AD). Analyses of these risk factors have focused attention upon the role of immune processes in AD, specifically microglial function. In this review, we discuss interpretation of genetic studies. We then focus upon six genes implicated by AD genetics that impact microglial function: TREM2, CD33, CR1, ABCA7, SHIP1, and APOE. We review the literature regarding the biological functions of these six proteins and their putative role in AD pathogenesis. We then present a model for how these factors may interact to modulate microglial function in AD

Conformational and Structural Relaxations of Poly(ethylene oxide) and Poly(propylene oxide) Melts: Molecular Dynamics Study of Spatial Heterogeneity, Cooperativity, and Correlated Forward-Backward Motion

Performing molecular dynamics simulations for all-atom models, we characterize the conformational and structural relaxations of poly(ethylene oxide) and poly(propylene oxide) melts. The temperature dependence of these relaxation processes deviates from an Arrhenius law for both polymers. We demonstrate that mode-coupling theory captures some aspects of the glassy slowdown, but it does not enable a complete explanation of the dynamical behavior. When the temperature is decreased, spatially heterogeneous and cooperative translational dynamics are found to become more important for the structural relaxation. Moreover, the transitions between the conformational states cease to obey Poisson statistics. In particular, we show that, at sufficiently low temperatures, correlated forward-backward motion is an important aspect of the conformational relaxation, leading to strongly nonexponential distributions for the waiting times of the dihedrals in the various conformational statesComment: 13 pages, 13 figure

New species of Tulasnella associated with terrestrial orchids in Australia

Recent studies using sequence data from eight sequence loci and coalescent-based species delimitation methods have revealed several species-level lineages of Tulasnella associated with the orchid genera Arthrochilus, Caleana, Chiloglottis, and Drakaea in Australia. Here we formally describe three of those species, Tulasnella prima, T. secunda, and T. warcupii spp. nov., as well as an additional Tulasnella species associated with Chiloglottis growing in Sphagnum, T. sphagneti sp. nov. Species were identified by phylogenetic analyses of the ITS with up to 1.3 % sequence divergence within taxa and a minimum of 7.6 % intraspecific divergence. These new Tulasnella (Tulasnellaceae, Cantharellales) species are currently only known from orchid hosts, with each fungal species showing a strong relationship with an orchid genus. In this study, T. prima and T. sphagneti associate with Chiloglottis, while T. secunda associates with Drakaea and Caleana, and T. warcupii associates with Arthrochilus oreophilu