Effects of high and low cut on Achilles tendon kinetics during basketball specific movements

The aim of the current investigation was to examine the influence of high and low-cut specific basketball footwear in relation to minimalist and conventional athletic footwear on the loads experienced by the Achilles tendon during basketball specific movements. Ten males performed run and 45˚ cut movements whilst wearing low-cut, high-cut, minimalist and conventional athletic footwear. Achilles tendon forces were calculated using Opensim software allowing the magnitudinal and temporal aspects of the Achilles tendon force to be quantified. Differences in Achilles tendon load parameters were examined using 4 (footwear) x 2 (movement) repeated measures ANOVA. The results show that a main effect was evident for peak Achilles tendon force, which was significantly larger in the minimalist (run = 5.74 & cut = 5.85 BW) and high-cut (run = 6.63 & cut = 6.01 BW) footwear in relation to the low-cut (run = 5.79 & cut = 5.47 BW) and conventional (run = 5.66 & cut = 5.34 BW) conditions. In addition a main effect was also evident for Achilles tendon load rate, which was significantly larger in the minimalist (run = 48.84 & cut = 43.98 BW/s) and high-cut (run = 54.31 & cut = 46.51 BW/s) footwear in relation to the low-cut (run = 43.15 & cut = 31.57 BW/s) and conventional (run = 44.74 & cut = 31.15 BW/s) conditions. The current investigation indicates that minimalist and high-cut footwear may place basketballers at increased risk for Achilles tendon pathology as a function of their training/ competition. Furthermore, it appears that for basketballers who may be susceptible to Achilles tendinopathy that low-cut and conventional conditions are most appropriate

The effects of CrossFit and minimalist footwear on Achilles tendon kinetics during running

The aim of the current investigation was to comparatively assess the influence of barefoot, CrossFit, minimalist and conventional footwear on the loads experienced by the Achilles tendon during running. Twelve male runners (27.81 ± 7.02 years, height 1.77 ± 0.11 cm and body mass 76.22 ± 7.04 kg) ran at 4.0 m·s-1 in each of the four footwear conditions. Achilles tendon forces were calculated using a musculoskeletal modelling approach allowing the magnitudinal and temporal aspects of the Achilles tendon force to be quantified. Differences between footwear were examined using one-way repeated measures ANOVA. The results showed the peak Achilles tendon force was significantly larger when running barefoot (5.81 ± 1.21) and in minimalist footwear (5.64 ± 1.03 BW) compared to conventional footwear (5.15 ± 1.05 BW). In addition it was revealed that Achilles tendon impulse was significantly larger when running barefoot (0.77 ± 0.22 BW.s) and in minimalist footwear (0.72 ± 0.16 BW.s) in comparison to both conventional footwear (0.64 ± 0.15 BW.s). Given the proposed association between high Achilles tendon forces and tendon degradation, the outcomes from the current investigation indicate that CrossFit athletes who select barefoot and minimalist footwear for their running training may be at increased risk from Achilles tendon pathology in comparison to conventional footwear conditions

Effect of gain and phase errors on SKA1-low imaging quality from 50-600 MHz

Simulations of SKA1-low were performed to estimate the noise level in images produced by the telescope over a frequency range 50-600 MHz, which extends the 50-350 MHz range of the current baseline design. The root-mean-square (RMS) deviation between images produced by an ideal, error-free SKA1-low and those produced by SKA1-low with varying levels of uncorrelated gain and phase errors was simulated. The residual in-field and sidelobe noise levels were assessed. It was found that the RMS deviations decreased as the frequency increased. The residual sidelobe noise decreased by a factor of ~5 from 50 to 100 MHz, and continued to decrease at higher frequencies, attributable to wider strong sidelobes and brighter sources at lower frequencies. The thermal noise limit is found to range between ~10 - 0.3 $\mu$Jy and is reached after ~100-100 000 hrs integration, depending on observation frequency, with the shortest integration time required at ~100 MHz.Comment: 23 pages, 11 figures Typo correcte

THE EFFECT OF RESISTED AND ASSISTED FREESTYLE SWIMMING ON STROKE MECHANICS

A three-dimensional analysis was conducted on the stroke mechanics of four female junior elite swimmers. They swam one 50 m freestyle trial for each of three conditions: resisted, assisted, and free swimming. Stroke length (SL), stroke rate (SR), maximum hand depth (rnax hand depth), body roll, and average forward velocity (avg fwd v) were evaluated. There was a significant difference (p < 0.05) found between conditions among SL. SR, rnax hand depth, and avg fwd v. During the resist trial, SL, SR, max hand depth, and avg fwd v all decreased. During the assist trial, SL, SR, avg fwd v increased, and rnax hand depth decreased. The changes due to resisted swimming suggest an undesirable affect on stroke mechanics. While some changes seen in assisted swimming may appear beneficial, both methods of tethered training remain questionable

CHANGES IN STROKE KINEMATICS DURING RESISTED AND ASSISTED FREESTYLE SWIMMING

Ten subjects swam 50m freestyle trials using; resisted (RS), assisted (AS), and free swimming (FS). Data from 2 underwater cameras were combined to provide a 3-D reconstruction of each trial. During RS, the stroke length (SL), mean 3D resultant hand velocity and average forward velocity (AV) significantly (p < 0.05) decreased compared to the FS trial. During RS, the swimmers were unable to generate enough force to prevent the tether from slowing them down. Further, calculations suggest that the average propulsive force acting on the swimmer was not increased during RS. During the AS trial SL, stroke rate and AV increased, while maximum hand depth decreased relative to the FS trial. There appear to be some positive benefits, however the technique changes found during both RS and AS result in these forms of training remaining questionable

Challenges of Securing Massively Multiplayer Online Games

When it comes to security in the modern world, things have improved a lot since the early 2000s. Hypertext Transfer Protocol Secure (HTTPS) and Transport Layer Security (TLS) have made the transfer of our data across the internet much safer than years prior, and the advent of VPNs and private browsing have only compounded that. However, the gaming industry has been notoriously behind the curve when it comes to security, most notably with Massively Multiplayer Online (MMO) games, which due to the intrinsic nature of their architecture, have an astounding amount of ground to cover. In this paper, the authors discuss the challenges that MMO developers face when trying to design a secure game, as well as some more modern approaches to security that will help improve the industry moving forward. The authors also highlight a few real-life examples of exploits and breaches that have happened and look at how they were mitigated

Understanding the components of specific weight in barley grains: opportunities for improving grain quality and processing efficiency.

Spring barley is the primary cereal crop grown in Scotland, 35% of the crop is used for malting and 55% for animal feed. There is a clear distinction between barley destined for malting or feed, this is a result of the higher quality grain demanded for malting and consequently a premium is paid for this. For example, in the UK during September 2018 malting barley reached prices of £46/t more than that of feed barley. Quality requirements for malting barley include: germination rate, per cent admixture, nitrogen levels, cultivar, moisture content, uniformity, skinning level, disease/weathering damage and specific weight (SW). Therefore different agronomic approaches are taken when a grower is striving for either malting or feed barley. The majority of these malting barley quality requirements are well understood, SW is well established however its impact on malting outputs or efficiency are not well understood. Specific weight is one of the longest standing measures of grain quality for cereals and oilseeds, it is a measure of the weight of grain per unit volume and is reported in kilograms per hectolitre (kg hl-1 ). An increased SW is thought to be beneficial for malt output. The aim of this thesis is to enhance the understanding of SW as a measure of grain quality, and to establish what aspects of barley grain determine this measure. Following establishing these grain traits, the aim is then to relate these to the malting process and outputs, to understand how SW influences malting. Firstly, SW has been demonstrated to have two components: grain density and packing efficiency. This is a key part of the thesis, because both components can change independently. Different grain parameters influence each of the components, therefore both need to be considered together when investigating SW differences or similarities between samples. The packing efficiency and grain density of nine spring barley cultivars was investigated, this demonstrated that grain density contributed 48.5% to the variation in SW and packing efficiency 36.5% to the variation in SW. It was hypothesised that the packing efficiency of grains was primarily influenced by grain morphometrics, and grain density influenced by composition. Investigating how composition changes with grain density was investigated by first stratifying grains by density, resulting in groups of grains with different densities. Compositional analyses were then carried out on these groups which showed that grain nitrogen level and the proportional volume of starch B-type granules contributed 47% to the observed variation in grain density. Specific weight is also known to be affected by growing conditions, with year to year variation observed. Such year-on-year variations might be a result of changing climatic conditions between years, therefore the effect of a moderate, but prolonged water stress was investigated under glasshouse conditions. Plant development was altered by the stress, but SW was maintained through compensatory mechanisms. To investigate how changes in SW affect malt quality parameters, SW was manipulated through selection for different grain size and weights. Specific weight was shown to be strongly correlated with the predicted spirit yield and hot water extract of the malt. These are two fundamental measures of malt quality. Grain density also correlated with these two measures, but packing efficiency of the grains did not. This indicates that it is grain density rather than the packing efficiency of the grain that is the beneficial component of SW for malting. Therefore if breeding of elite malting cultivars is continued to enhance malt quality through increasing SW, this should be done so through increasing the grain density component rather than packing efficiency

Validation du « Hunt Squash Accuracy Test » pour évaluer la performance des joueurs dans l'exécution de leurs coups

This study examined the validity of the Hunt Squash Accuracy Test (HSAT) for predicting within-game shot performance and tournament rank. Shots from eight male junior squash players performing the HSAT and tournament match-play were analysed. A typical-error analysis from repeated trials showed the HSAT to be very reliable (1.82%). HSAT rank had significant correlations (p < 0.05) to tournament rank (r = 0.98) and tournament shot success (r = 0.95). HSAT score showed significant correlations to the percentage of winning shots during match-play (r = 0.88). HSAT shots with significant correlations to successful match-play shots were backhand-drive (r = 0.92) and backhand-volley (r = 0.97). These results suggest the HSAT is a valid method of assessing the accuracy and performance of junior squash players. It could potentially be used to track shot improvements and predict match-play performance

Building a Better Orono Together: Cultivating Organic Community Connection with University and Orono Stakeholders Final Report

Final report for POS 364-365 Practicum in Engaged Policy Studies I and II with Professor Robert Glover, University of Maine