A Model for Multilevel Phase-Change Memories Incorporating Resistance Drift Effects

Phase change memories are emerging as a most promising technology for future nonvolatile, solid-state, electrical storage. However, to compete effectively in mainstream storage applications, a multilevel cell capability is most desirable. Unfortunately, phase-change memories exhibit a temporal drift in programmed resistance (and in threshold switching voltage) which appears to be a fundamental and universal property of the amorphous or partially amorphous phase. Phase-change device models should therefore include these drift effects in a realistic way so that circuit and systems designers can assess the likely performance of multilevel phase-change memories in a variety of potential applications. In this paper, therefore, we present a comprehensive SPICE-based model for phase-change devices that includes the capability for programming into multiple resistance levels, the prediction of the drift of cell resistance (and threshold voltage) with time, and the capability for modeling the randomness inherent to the resistance drift phenomenon. Simulations of multilevel programming and drift phenomena using the model are presented and compared to experimental results, with which there is very good agreement

VARIABILITY AND THE CONTROL OF ROTATION DURING SPRINGBOARD DIVING

This study explored the variability in angular velocity profiles across multiple somersault dives. Four international level divers performed 4-6 repeated dives of either 3½ somersaults with pike, or 4½ with tuck, from a 3 m springboard. An inertial measurement unit (IMU) was attached to the lower back to record angular velocity during all trials. Each diver produced highly consistent patterns of dive time duration and angular velocity, with standard deviations less than 1% of the mean. No consistent pattern of correlation between velocity and duration of the held tuck/pike position was apparent, and no other evidence of mid-dive feedback control was evident from the present methodology. This may be the result of performing dives with a high degree of difficulty, providing little time for movement adjustments during 'kick out' to affect water-entry

A KINEMATIC ANALYSIS OF THE BACKWARD 2.5 SOMERSAULTS WITH 1.5 TWISTS DIVE (5253B) FROM THE 3M SPRINGBOARD

The aim of this case study was to determine the practical application of 3D inertial measurement units and compare angular velocity profiles, key position angles and event timings for the backward 2½ somersaults with 1½ twists (5253B). One male diver performed 11 trials of the 5253B while 3D inertial measurement units (IMU) and high speed video were used to measure kinematic variables. Peak angular velocity about the somersault and twist axes were 900±11deg/s and -1435±28.deg/s, with highly consistent patterns displayed for total flight time

Asymmetric Organocatalysis and Continuous Chemistry for an Efficient and Cost-Competitive Process to Pregabalin

Herein, we present the scale up development of an innovative synthetic process to pregabalin. The process is underpinned by two enabling technologies critical to its success; continuous chemistry allowed a safe and clean production of nitroalkene, and asymmetric organocatalysis gave access to the chiral intermediate in an enantioenriched form. Crucial to the success of the process was the careful development of a continuous process to nitroalkene and optimization of the organocatalyst and of the reaction conditions to attain remarkably high turn-over frequency in the catalytic asymmetric reaction. Successful recycle of the organocatalysts was also developed in order to achieve a cost-competitive process

Movement and Physiological Demands of Australasian National Rugby League Referees.

Purpose: To evaluate the movement and physiological demands of the Australasian National Rugby League (NRL) referees, officiating with a ‘two referee’ (i.e., ‘lead’ and ‘pocket’) system and to compare the demands of the lead referee and pocket referees. Methods: 10 Hz global positioning system devices were used to obtain 86 data sets (‘lead’, n=41; ‘pocket’, n=45) on 19 NRL referees. Total distance, relative distance covered and heart rate per half and across match-play was examined within and between referees using t-tests. Distance, time and number of movement 'efforts' were examined in six velocity classifications (i.e., standing 7.0 m.s-1) using ANOVA. Cohen's d effect sizes were reported. Results: There were no significant differences between the ‘lead’ and ‘pocket’ referee for any movement or physiological variable. There was an overall significant (large; very large) effect for distance (% distance) and time (% time) (P 5.51 m.s-1. Conclusions: Findings highlight the intermittent nature of rugby league refereeing, but show that there were no differences in the movement and physiological demands of the two refereeing roles. Findings are valuable for those responsible for the preparation, training and conditioning of NRL referees, and to ensure training prepares for and simulates match demands

Understanding the role of the stroke physician in early supported discharge services. Collaborative Leadership in Applied Health rRsearch and Care (CLAHRC), Nottinghamshire, Derbyshire and Lincolnshire, UK

Our recent research, using expert consensus with trialists who had contributed to the Cochrane systematic review, has helped to establish key components of effective Stroke Early Supported Discharge (ESD) services. One essential element is that the ESD multidisciplinary team should have access to specialist stroke knowledge. However, how this is organised and put into working practice is less well-defined

Successful implementation of stroke early supported discharge services. Collaborative leadership in applied health research and care (CLAHRC), Nottinghamshire, Derbyshire and Lincolnshire, UK

A Cochrane systematic review demonstrated that ESD services can reduce long-term dependency and admission to institutional care as well as reducing the length of hospital stay. No adverse impact on the mood or well-being of patients or carers was reported. This ongoing study aims to facilitate and evaluate the successful implementation of Stroke Early Supported Discharge (ESD) services across Nottinghamshire, Derbyshire and Lincolnshire, UK. This study is being conducted to ensure that the health and cost benefits are still in evidence when ESD services are implemented into local areas