New Relations for Three-Dimensional Supersymmetric Scattering Amplitudes

We provide evidence for a duality between color and kinematics in three-dimensional supersymmetric Chern-Simons matter theories. We show that the six-point amplitude in the maximally supersymmetric, N=8, theory can be arranged so that the kinematic factors satisfy the fundamental identity of three-algebras. We further show that the four- and six-point N=8 amplitudes can be "squared" into the amplitudes of N=16 three-dimensional supergravity, thus providing evidence for a hidden three-algebra structure in the dynamics of the supergravity.Comment: 8 pages, 2 figure

Monitoring anthropometry and fitness using maturity groups within youth rugby league.

The purpose of the present study was to evaluate the anthropometry and fitness, and change in these characteristics over time, of youth rugby league players by using maturity status to determine annual categories instead of traditional chronological annual-age grouping. One hundred and twenty one male rugby league players were assessed using anthropometric (i.e., height, sitting height, body mass and sum of four skinfolds) and fitness (i.e., vertical jump, medicine ball chest throw, 10m and 20m sprint and multi stage fitness test; MSFT) measures over a 5 year period. Each player was classified into one of six maturity groups based on their maturity offset (Years from Peak Height Velocity; i.e., 1.5 YPHV). MANOVA analyses identified significant (p<0.001) main effects for maturity group for cross-sectional characteristics and longitudinal change in performance over time. Analyses demonstrated that more mature groups had greater anthropometric and fitness characteristics, except for endurance performance (MSFT -2.5 YPHV = 1872 ± 18 m vs 2.5 YPHV = 1675 ± 275m). For longitudinal changes in characteristics over time, a significant effect was only identified for height and sitting height (p<0.05). These findings provide comparative data for anthropometric and fitness characteristics and change in performance over time in accordance to maturity status within youth rugby league players. Classifying players into annual maturity groups may be an additional or alternative assessment method for evaluating anthropometry and fitness performance in adolescent populations. Further, tracking performance changes over time, especially in relation to maturation, may reduce the limitations associated with chronological annual-age grouping

Effects of an intensifed competition period on neuromuscular function in youth rugby union players

Playing rugby union matches causes a number of fatigue responses, including reduced lower body neuromuscular function (NMF) (commonly measured by counter movement jump (CMJ))(1). The time course of this response following match play is well established in professional (2) and academy (3) level rugby union players, who take at least 60 hours for NMF to recover. No data exist for high school level rugby union players, but these players are often exposed to multiple game tournaments and festivals (2 games in 3 days, or 3 games in 5 days) within their competition structures. Aim. The aim of this case study is to document the NMF response to playing three rugby union matches within five days. This will provide useful information to practitioners who must manage fatigue and recovery of youth rugby union players who play multiple games within short time periods

Monitoring workloads in collision sports: External load measures alone may not provide the full picture

PURPOSE: To compare the external loads and external:internal load ratios (EL:IL) during match-play of adolescent collision sport athletes playing at both elite (i.e., academy) and sub-elite (i.e., school) standards. METHODS: Following ethics approval, seventeen elite adolescent male rugby union players (mean ± SD age = 17 ± 1 years) were recruited for this study. Global positioning system (GPS) locomotor (i.e., relative distance [RD; m·min-1], low speed activity [LSA; relative distance <61% maximum velocity [Vmax]], high speed running [HSR; relative distance ≥61% Vmax]), and accelerometer (relative PlayerLoadTM [RPL; AU·min-1], PLSLOW [relative accelerations <2 m·s-1], PLFAST [relative accelerations ≥2 m·s-1]) external loads, and session rating of perceived exertion (sRPE) internal load measures were obtained from 22 matches resulting in 86 match files (39 sub-elite and 47 elite match files; 5 ± 2 match files per subject). Perceptual wellbeing measures (i.e., fatigue, sleep quality, upper-body and lower-body soreness, stress, and mood) were also recorded using a 5-point Likert scale on the mornings pre- and post-match. Data were analysed using Cohen’s d effect sizes (d) and magnitude-based inferences. RESULTS: Differences in external loads were unclear between playing standards for RD (d = -0.2) and RPL (d = 0.0). However, subjects’ EL:IL were very likely lower during elite compared to sub-elite matches for both RD:sRPE (d = -1.0) and RPL:sRPE (d = -0.8), due to the very likely greater sRPE during elite matches (d = -1.1). There were unclear differences between sub-elite and elite matches for distribution of GPS and accelerometer variables (i.e., LSA, HSR, PLSLOW, and PLFAST; Table 1). Changes in total perceptual wellbeing were possibly greater following elite compared to sub-elite matches, with unclear differences for changes in sleep quality, lower-body soreness, stress and mood. However, changes in perceptual fatigue and upper-body soreness were both likely greater following elite matches. CONCLUSIONS: Adolescent rugby union players had similar locomotor and accelerometer external loads (i.e., RD, LSA, HSR, RPL, PLSLOW and PLFAST) during both elite and sub-elite standard matches. However, EL:IL was substantially reduced in higher standard matches, indicating a higher perception of effort for a given external load. Greater changes in perceptual fatigue and upper-body soreness following elite match-play may be related to greater magnitude of collision-based activity at higher playing standards. This may be due to the increased body mass and running velocities of opponents at higher playing standards, which may not be fully accounted for using external load measures alone. PRACTICAL APPLICATION: As collision sports require more than just movement and acceleration demands, the inclusion of subjective load measures (i.e., sRPE) or EL:IL may provide a further insight to the true demands of training or match-play than GPS and accelerometer data alone

Spindle-E acts antivirally against alphaviruses in mosquito cells

Mosquitoes transmit several human- and animal-pathogenic alphaviruses (Togaviridae family). In alphavirus-infected mosquito cells two different types of virus-specific small RNAs are produced as part of the RNA interference response: short-interfering (si)RNAs and PIWI-interacting (pi)RNAs. The siRNA pathway is generally thought to be the main antiviral pathway. Although an antiviral activity has been suggested for the piRNA pathway its role in host defences is not clear. Knock down of key proteins of the piRNA pathway (Ago3 and Piwi5) in Aedes aegypti-derived cells reduced the production of alphavirus chikungunya virus (CHIKV)-specific piRNAs but had no effect on virus replication. In contrast, knock down of the siRNA pathway key protein Ago2 resulted in an increase in virus replication. Similar results were obtained when expression of Piwi4 was silenced. Knock down of the helicase Spindle-E (SpnE), an essential co-factor of the piRNA pathway in Drosophila melanogaster, resulted in increased virus replication indicating that SpnE acts as an antiviral against alphaviruses such as CHIKV and the related Semliki Forest virus (SFV). Surprisingly, this effect was found to be independent of the siRNA and piRNA pathways in Ae. aegypti cells and specific for alphaviruses. This suggests a small RNA-independent antiviral function for this protein in mosquitoes

Do physical qualities influence the attainment of professional status within elite 16-19 year old rugby league players?

OBJECTIVES The current study retrospectively compared the physical qualities of elite academy rugby league players (aged 16-19 years) by career attainment level (i.e., academy or professional). DESIGN: Retrospective cross-sectional and longitudinal design. METHODS: Eighty-one academy rugby league players were assessed for physical qualities (height, body mass, skinfolds, speed, momentum, vertical jump, Yo-Yo Level 1 and 1-RM squat, bench press and prone row) at the Under 17-19 age categories between 2007 and 2012. Player's career attainment level was determined in 2014. Longitudinal changes in physical qualities between Under 17 and 19s were compared by career attainment level. RESULTS: Professional players demonstrated moderate significant advantages for height (d=0.98) and 1-RM squat (d=0.66) at the Under 17s, 1-RM bench press (d=0.76) at the Under 18s and 1-RM prone row (d=0.73) at the Under 19s age categories when compared to academy players. When assessed longitudinally (Under 17s-19s), professional players significantly outperformed academy players for 1-RM squat (η2=0.20). Professional players also demonstrated greater increases in body mass (8.2 vs. 2.9kg) and 10m momentum (47 vs. 17kgs-1) than academy players between the Under 17s and 19s. CONCLUSIONS: Advanced physical qualities, particularly height and absolute strength, within 16-19 year old players may contribute to attaining professional status in rugby league. Further, the development of body mass and momentum for players within an academy is an important consideration in the progress towards professional rugby league. Therefore, practitioners should aim to identify and develop the physical qualities, especially size and strength, within academy rugby league players

A sex difference in the response of the rodent postsynaptic density to synGAP haploinsufficiency

SynGAP is a postsynaptic density (PSD) protein that binds to PDZ domains of the scaffold protein PSD-95. We previously reported that heterozygous deletion of Syngap1 in mice is correlated with increased steady-state levels of other key PSD proteins that bind PSD-95, although the level of PSD-95 remains constant (Walkup et al., 2016). For example, the ratio to PSD-95 of Transmembrane AMPA-Receptor-associated Proteins (TARPs), which mediate binding of AMPA-type glutamate receptors to PSD-95, was increased in young Syngap1+/- mice. Here we show that only females and not males show a highly significant correlation between an increase in TARP and a decrease in synGAP in the PSDs of Syngap1+/- rodents. The data reveal a sex difference in the adaptation of the PSD scaffold to synGAP haploinsufficiency