The Effects of Walking Surface and Vibration on the Gait Pattern and Vibration Perception Threshold of Typically Developing Children and Children with Idiopathic Toe Walking

The aim of the current study is to investigate novel therapeutic/treatment methods and outcome measurement for children with Idiopathic Toe Walking (ITW). Fifteen typically developing (TD) children and 15 children with ITW, aged between 4 to 10 years old, participated. The participants performed a gait exam including 30 barefoot walking trials over three 4-meter walkways before and after a whole-body vibration intervention. Vibration perception threshold tests were also conducted before and after the vibration intervention. In the gait exams, each of the walking surfaces represented a different tactile stimulus and the vibration intervention included standing on a whole body vibration platform for 60 seconds. Kinematics were collected at 100 Hz with a seven-camera 3-D motion analysis system. Walking surface and vibration intervention were the independent variables. Temporal-spatial gait parameters such as velocity, cadence, step length, and step width were measured. Heel rise occurrence (HR32) and vibration perception threshold (VPT) were also calculated as dependent variables. Walking surface significantly altered the gait parameter of both TD children and children with ITW. Vibration intervention altered the VPT scores of both TD children and children with ITW. Manipulated surface and excessive vibration may be important in the development of therapeutic/treatment methods for children with Idiopathic Toe Walking. HR32 is a novel calculation designed to distinguish on aspect of the toe-walking gait pattern. It significantly identified toe-walking patterns and quantified treatment results. Children with ITW appeared to have less toe-walking on the gravel surface. Walking on gravel surface is a potential novel method to reduce toe-walking immediately with no negative after-effects

EFFECTS OF ONE AND TWO HANDED TENNIS BACKHANDS HIT WITH VARIED POWER LEVELS ON TORSO ROTATION

This study examined hitting one & two hand backhands with moderate and maximal power on the shoulder, hip, and trunk rotations during a tennis groundstroke by collegiate male and female tennis players. Video images from two views at 60 Hz were collected as players hit backhand strokes with a ball launched from a serving stand. Each subject hit 10 trials with moderate and maximal power using one & two hand backhands to a 2x2 m target area. Average ball velocities for stroke conditions were determined and 2 trials closest to the condition average velocity were analyzed with Ariel APAS. ANOVA on the shoulder rotations found significant hand and power factors, where maximal power and two hand backhands used more shoulder motion. The two hand backhand produced greater hip rotation and the female subjects used more trunk rotation with a two handed backhand

Near-Optimal Defense Strategies against DDoS Attacks Based upon Packet Filtering and Blocking Enabled by Packet Marking

In the paper, the DDoS scenario is modelled as a mathematical programming problem. The defender strategically utilizes the limited resources to maximize the legitimate traffic, and he can adopt packet marking to observe the network status. The information extracts from the marking field can help the defender develop a defense strategy which combines packet filtering and packet blocking. A Lagrangean relaxation-based algorithm is proposed to optimally solve the problem

Game Analysis, Validation, and Potential Application of EyeToy Play and Play 2 to Upper-Extremity Rehabilitation

Objective. To describe and analyze the potential use of games in the commercially available EyeToy Play and EyeToy Play 2 on required/targeted training skills and feedback provided for clinical application. Methods. A summary table including all games was created. Two movement experts naïve to the software validated required/targeted training skills and feedback for 10 randomly selected games. Ten healthy school-aged children played to further validate the required/targeted training skills. Results. All but two (muscular and cardiovascular endurance) had excellent agreement in required/targeted training skills, and there was 100% agreement on feedback. Children’s performance in required/targeted training skills (number of unilateral reaches and bilateral reaches, speed, muscular endurance, and cardiovascular endurance) significantly differed between games . Conclusion. EyeToy Play games could be used to train children’s arm function. However, a careful evaluation of the games is needed since performance might not be consistent between players and therapists’ interpretation

The role of catalyst acidity and shape selectivity on products from the catalytic fast pyrolysis of beech wood

The catalytic fast pyrolysis (CFP) of biomass represents an efficient integrated process to produce deoxygenated stable liquid fuels and valuable chemical products from lignocellulosic biomass. The zeolite ZSM-5 is a widely studied catalyst for the CFP process. However, its microporous structure may limit the diffusion of high molecular weight pyrolysis intermediates to its active sites. Mesoporous aluminosilicates such as Al-SBA-15 are promising materials with larger pore sizes that can overcome these diffusional limitations. Previous comparisons between mesoporous aluminosilicates and ZSM-5 for the CFP process have neglected the disproportionately high acidity of ZSM-5. In this study, an Al-SBA-15 catalyst has been synthesised with high acidity, comparable to that of a ZSM-5 catalyst with a Si:Al ratio of 15:1. The synthesised Al-SBA-15 catalyst was characterised by N2 physisorption, XRD and propylamine-TPD, and was compared to a ZSM-5 catalyst and a typical industrial equilibrium fluid catalytic cracking catalyst (e-FCC). All three catalysts were used at three different catalyst to biomass (C/B) ratios, to investigate the effect of varying concentrations of acid sites on the product distribution from the catalytic fast pyrolysis of beech wood. Interestingly, despite their dissimilar structural architectures, all three solid acid catalysts displayed similar reaction pathways towards the cracking of high molecular weight products such as levoglucosan and formation of intermediates including phenolics and furans. However, the selectivity towards the final catalytic products was dictated mainly by the structure of the catalysts. Despite their very similar surface area and acidity, the ZSM-5 exhibited high selectivity for the formation of desirable aromatic hydrocarbon products due to its shape-selective micropore structure, while Al-SBA-15 instead shifted the selectivity towards the formation of undesirable coke. The results highlighted the importance of catalyst shape-selectivity in the catalytic fast pyrolysis of biomass for the conversion of pyrolysis vapours into desirable products and the suppression of undesirable solid byproduct formation