Snap-Through of Unsymmetric Laminates Using Piezocomposite Actuators

The paper discusses the concept of using a piezoceramic actuator bonded to one side of a two-layer unsymmetric cross-ply [0/90]T laminate to provide the moments necessary to snap the laminate from one stable equilibrium shape to another. This concept could be applied to the morphing of structures. A model of this concept, which is based on the Rayleigh-Ritz technique and the use of energy and variational methods, is developed. The experimental phase of the study is discussed, including the measurement of the voltage level needed to snap the laminate. The voltage measurements and shapes are compared with predictions of the models and the agreement between measurements and the predictions are reasonable, both qualitatively and quantitatively. Suggestions for future activities are presented

Examining the validity, reliability and feasibility of capturing children's physical literacy through games-based assessment in physical education

Background Observational tools can help refine practice design and guide the creation of effective learning environments. The intention of this study was to design and validate an observational instrument for assessing physical literacy that remains more faithful to the philosophically complex and holistic nature of the concept. Methods Framed by concepts of ecological dynamics, the emergent games-based assessment tool enables capture of children's interactions with their environment, providing insight on the manifestation of physical literacy within physical education games. The design and validation of the instrument consisted of a multistage process: (1) design of the observational instrument and establishing face validity; (2) pilot observation study; (3) expert qualitative and quantitative review to establish content validity; (4) observation training; and (5), establishing observer reliability. Results Following expert qualitative and quantitative evaluation, Aiken's V coefficient was used to determine content validity. Results achieved demanding levels of validity (V ≥ 0.78) for all retained measurement variables. Cohen's κ values for inter- and intra-observer reliability ranged from 0.331 to 1.00 and 0.552 to 1.00, generally reporting “substantial” agreement during inter-observer analysis and “substantial” to “almost perfect” agreement during intra-observer analysis. Conclusions The final model of the emergent games-based assessment tool, with 9 ecological conceptualisations of behaviour, 15 measurement variables, and 44 categorical observational items was found to be valid and reliable, providing both educators and researchers with a useful mechanism to assess physical literacy during gameplay

Examining the validity, reliability and feasibility of capturing children's physical literacy through games-based assessment in physical education

Background: Observational tools can help refine practice design and guide the creation of effective learning environments. The intention of this study was to design and validate an observational instrument for assessing physical literacy that remains more faithful to the philosophically complex and holistic nature of the concept. Methods: Framed by concepts of ecological dynamics, the emergent games-based assessment tool enables capture of children's interactions with their environment, providing insight on the manifestation of physical literacy within physical education games. The design and validation of the instrument consisted of a multistage process: (1) design of the observational instrument and establishing face validity; (2) pilot observation study; (3) expert qualitative and quantitative review to establish content validity; (4) observation training; and (5), establishing observer reliability. Results: Following expert qualitative and quantitative evaluation, Aiken's V coefficient was used to determine content validity. Results achieved demanding levels of validity (V ≥ 0.78) for all retained measurement variables. Cohen's κ values for inter- and intra-observer reliability ranged from 0.331 to 1.00 and 0.552 to 1.00, generally reporting “substantial” agreement during inter-observer analysis and “substantial” to “almost perfect” agreement during intra-observer analysis. Conclusions: The final model of the emergent games-based assessment tool, with 9 ecological conceptualisations of behaviour, 15 measurement variables, and 44 categorical observational items was found to be valid and reliable, providing both educators and researchers with a useful mechanism to assess physical literacy during gameplay

Isokinetic strength qualities that differentiate rapid deceleration performance in male youth academy soccer players

Introduction Decelerating (DEC) is just as frequent as accelerating in contemporary soccer match play (Russell et al., 2014). Recent evidence suggests that lower body eccentric strength directly improves the ability of a player to produce and tolerate braking forces (Spiteri et al., 2014). The aim of the present study was to identify if measures of isokinetic strength can differentiate performance of a rapid DEC maneuver. Method Nineteen (n=19) academy youth soccer players (age: 16.7 + 1yrs; height: 175 + 8.4cm ; body mass: 69.1+ 7.5kg; body fat: 9.5 + 3.9%) participated in the study. Tests included: isokinetic dynamometer (Cybex ΙΙ, Cybex International Inc., New York, USA) strength profiling of quadricep (Q) and hamstring (H) peak concentric (con) and eccentric (ecc) torque (both dominant [kicking leg] and non-dominant legs) assessed at slow (60°/s) and fast (180°/s) angular velocities. Functional H:Q ratios representative of knee flexion (Hcon:Qecc) and extension (Hecc:Qcon) was also calculated; 30m linear sprint time (with 5m, 10m and 20m splits) was recorded using a single beam timing system (Witty, Microgate, Italy) and rapid DEC quantified using time to stop (TTS) and distance to stop (DTS) determined following a 20m maximal acceleration (within 5% threshold of best 20m linear sprint time) using video analysis (Dartfish ProSuite 2011, Fribourg, Switzerland) captured from a 50Hz video camera (Panasonic HDC-HS900, Japan). Results 10, 20 and 30m sprint times had significantly large correlations with fast con peak Q torque (dom, r=-0.624, -0.568, - 0.621 and non-dom, r=-0.513, -0.512, -0.509) with fast peak H torque comprising significant correlations in the dom leg (r= -0.773, -0.561, -0.761) with moderate to large correlations in the non-dom leg (r= -0.5, -0.468, -0.464). At slow velocity con peak H torque had moderate to large correlations with 10, 20 and 30m sprint times. No significant correlations were found for peak con strength in either Q or H for DEC performance (TTS and DTS). Slow velocity Ecc peak Q torque (dom, r= -0.503, nondom, r=-0.542) and time to peak torque (r=-0.465) was significantly correlated to DEC TTS. No significant correlations were found for fast ecc strength parameters in Q or H for either sprint or DEC performance. Sprint and DEC performance had no significant correlations. Discussion The present study illustrates the need for specific strength qualities for attainment of high running velocities and rapid DEC performance. Specifically, players with superior sprint speed can produce high peak con forces in both Q and H at fast velocities. DEC seems to be a unique movement skill requiring specific ecc strength qualities. Interestingly, in this study slow velocity ecc strength of the Q seems to be critical for production of braking forces and reducing the time spent DEC. Increased time spent DEC has been found to increase tissue damage and muscle soreness, subsequently affecting post match recovery kinetics (Young et al., 2012). In conclusion this study highlights the need for careful consideration to developing strength qualities needed for DEC alongside those more commonly known for sprinting and accelerating. References Russell, M., Sparkes, W., Northeast, J., Cook, C. J., Love, T. D., Bracken, R. M., & Kilduff, L. P. (2014). Changes in acceleration and deceleration capacity throughout professional soccer match-play. Journal of Strength and Conditioning Research, in press. Spiteri, T., Nimphius, S., Hart, N. H., Specos, C., Sheppard, J. M., & Newton, R. U. (2014). Journal of Strength & Conditioning Research, 28(9), 2415–23. Young, W. B., Hepner, J., & Robbins, D. W. (2012). Journal of Strength and Conditioning Research, 26(2), 492–6

Full genome sequence and sfRNA interferon antagonist activity of Zika virus from Recife, Brazil

Background: The outbreak of Zika virus (ZIKV) in the Americas has transformed a previously obscure mosquito-transmitted arbovirus of the Flaviviridae family into a major public health concern. Little is currently known about the evolution and biology of ZIKV and the factors that contribute to the associated pathogenesis. Determining genomic sequences of clinical viral isolates and characterization of elements within these are an important prerequisite to advance our understanding of viral replicative processes and virus-host interactions. Methodology/Principal findings: We obtained a ZIKV isolate from a patient who presented with classical ZIKV-associated symptoms, and used high throughput sequencing and other molecular biology approaches to determine its full genome sequence, including non-coding regions. Genome regions were characterized and compared to the sequences of other isolates where available. Furthermore, we identified a subgenomic flavivirus RNA (sfRNA) in ZIKV-infected cells that has antagonist activity against RIG-I induced type I interferon induction, with a lesser effect on MDA-5 mediated action. Conclusions/Significance: The full-length genome sequence including non-coding regions of a South American ZIKV isolate from a patient with classical symptoms will support efforts to develop genetic tools for this virus. Detection of sfRNA that counteracts interferon responses is likely to be important for further understanding of pathogenesis and virus-host interactions

Tragicomic presentations of self : starring Phil Silvers as Bilko : the incomplete comic human

When a performer becomes over-associated with a particular, celebrated comic character can this lead to problems, not merely in terms of type-casting, but in creating confusions for the actor’s own perception of self? In instances where a comic creation is perceived to be an extension of the performer’s actual ‘self’, what dissonances in self construct may arise between the comic actor’s created persona and his/her own presentation of self? This article considers the nature of tensions created through the permeation of persona and person which can beset comedians who become closely identified with their particular mediated role. Can, indeed, over-association with their successful ‘signature’ comic role be seen to prove psychologically destabilising for certain performers whose own fragile, sense of identity becomes further compromised by presentation of their own most familiar and definitive, comic creations? Drawing specifically upon the career and comedy of Phil Silvers (aka ‘Sergeant ‘Bilko’), this article attempts to evaluate the forms of crises of identity that can arise between presentations of public and private selves for those performers who become, in effect, ‘public comic property’

Interpretative and predictive modelling of Joint European Torus collisionality scans

Transport modelling of Joint European Torus (JET) dimensionless collisionality scaling experiments in various operational scenarios is presented. Interpretative simulations at a fixed radial position are combined with predictive JETTO simulations of temperatures and densities, using the TGLF transport model. The model includes electromagnetic effects and collisions as well as □(→┬E ) X □(→┬B ) shear in Miller geometry. Focus is on particle transport and the role of the neutral beam injection (NBI) particle source for the density peaking. The experimental 3-point collisionality scans include L-mode, and H-mode (D and H and higher beta D plasma) plasmas in a total of 12 discharges. Experimental results presented in (Tala et al 2017 44th EPS Conf.) indicate that for the H-mode scans, the NBI particle source plays an important role for the density peaking, whereas for the L-mode scan, the influence of the particle source is small. In general, both the interpretative and predictive transport simulations support the experimental conclusions on the role of the NBI particle source for the 12 JET discharges

Ecological dynamics: a theoretical framework for understanding physical literacy in children

In recent years the concept of physical literacy has (re)emerged, gaining global popularity as an increasingly influential concept. Commonly expressed themes within academic literature highlight that physical literacy involves the equal consideration of movement competence, affective behaviours, knowledge, understanding, and the valuing of physical interactions with the environment. Developing a framework for the assessment of a multifaceted phenomenon such as physical literacy is acknowledged as being difficult. The often-taken route of decontextualised assessment, or disconnected evaluation fails to fully account for the role that environment and context have within the revelation of physical literacy. There has been encouragement to develop creative, nonconventional approaches to the evaluation of physical literacy that better reflect the holistic nature of the construct. In an attempt to address such shortcomings, this thesis outlines how the assessment of physical literacy, conceptualised in an ecological dynamics theoretical rationale might be undertaken. The emergent games-based assessment developed through this thesis is the first tool of its type which frames physical literacy assessment and evaluation through an ecological dynamics rationale, providing insight to children’s knowledge of the environment, revealed through their perception of affordances, their intentionality, and how they functionally move to effectively wayfind within performance environments. The studies presented provide a foundation for new perspectives on physical literacy assessment, providing a mechanism to successfully differentiate higher- and lower-physical literacy behaviour, while remaining more faithful to the philosophically complex and holistic nature of the concept