A fluid dynamic investigation of the Big Blade and Macon oar blade designs in rowing propulsion

The purpose of this investigation was to examine the fluid dynamic characteristics of the two most commonly used oar blades: the Big Blade and the Macon. Scaled models of each blade, as well as a flat Big Blade, were tested in a water flume using a quasi-static method similar to that used in swimming and kayaking research. Measurement of the normal and tangential blade forces enabled lift and drag forces generated by the oar blades to be calculated over the full range of sweep angles observed during a rowing stroke. Lift and drag force coefficients were then calculated and compared between blades. The results showed that the Big Blade and Macon oar blades exhibited very similar characteristics. Hydraulic blade efficiency was not therefore found to be the reason for claims that the Big Blade could elicit a 2% improvement in performance over the Macon. The Big Blade was also shown to have similar characteristics to the flat plate when the angle of attack was below 90 degrees , despite significant increases in the lift coefficient when the angle of attack increased above 90 degrees . This result suggests that the Big Blade design may not be completely optimized over the whole stroke.     

Longitudinal outcome effects of non-at-risk and at-risk transition first-grade samples: A follow-up study and further analysis

Fourth-grade follow-up achievement outcome data of placed and nonplaced transition extra-year school readiness samples indicate a nonsignificant standardized score difference, as noted in the second-grade findings. New analysis of correlation data indicates that within-sample age distribution shows a positive correlation with standardized achievement test scores in a study sample of non-at-risk students nonretained or recommended for retention. This age-achievement correlation is strong in kindergarten, with decreased effects by second and fourth grade. Four study samples of at-risk students (students retained in a transition extra-year school readiness program, students recommended and eligible for such placement but not placed, students retained in kindergarten through second grade, and students held out of school prior to kindergarten) reflect moderate inverse (negative) correlations between age and achievement test scores, with increasing inverse effects in fourth grade. Effect analysis and implications are discussed. © 1996 John Wiley & Sons, Inc.     

Compelled Disclosure of Scientific Research Data

Federal legislation requires that research produced with federal funding be available to the public under the Freedom of Information Act. I raise a concern that this power might be used to harass scientists. The goal of data sharing, however, is important, and should be facilitated through electronic data archiving.     

Can sit-to-stand muscle power explain the ability to perform functional tasks in adults with severe obesity?

This study examined the relationship between sit-to-stand (STS) power and physical function in adults with severe obesity. Thirty-eight adults (age: 44 ± 12 years; body mass index [BMI]: 45.2 ± 7.8 kg/m²) completed evaluations of STS power, strength and functional performance. STS power was measured with a wearable inertial sensor, strength was assessed with the isometric mid-thigh pull, and function was measured with the timed up-and-go (TUG), six-minute walk test (6MWT) and 30-s chair STS. Power and strength (normalised to body mass) entered regression models in addition to age, gender, BMI and physical activity (daily step count). Power displayed large univariate associations with TUG (r = 0.50) and 30-s chair STS (r = 0.67), and a moderate association with 6MWT (r = 0.49). Forward stepwise regression revealed that power independently contributed to TUG (β = ?0.40, p = 0.010), 30-s chair STS (β = 0.67, p < 0.001) and 6MWT performance (β = 0.27, p = 0.007). Power also appeared to be a superior determinant of function compared with strength. Power generated via the STS transfer largely underpins the ability to perform functional tasks in adults with severe obesity, although intervention studies are required to investigate a potentially causal relationship.     

Revel,Riot and Rebellion and The Social History of Politics

ABSTRACT

This article considers the ties between soldiers and civilian life in First World War Britain. Previous assumptions about soldierly alienation and disillusionment from civilian society have been questioned in recent years. This article adds to this discussion by examining the part played by National War Aims Committee propaganda in fostering links between soldiers and the home front. Representation of civilian activities, community, rurality and domesticity offered reassurance that Britain remained largely the same as soldiers remembered. The involvement of soldiers as propagandists also shows that attitudes cannot be deduced solely from the perspective of literary depictions of alienation.     

Force transducer system for measurement of ice hockey skating force

The purpose of this study was to develop a portable force measurement system for ice hockey skating. The system consisted of three strain gauge pairs affixed to an ice hockey skate’s blade holder with wire leads connected to a microprocessor controlled data acquisition device carried in a backpack worn by the skater. The configuration of the strain gauges simultaneously determined the vertical and medial–lateral force components experienced by the blade holder with a resolution accuracy of 1.9 N and a coefficient of variation of 9.2%. On-ice testing of this system with subjects performing forward start, acceleration, and constant velocity skating permitted unencumbered, natural movement and demonstrated clear, unambiguous signal responses, high trial-to-trial repeatability, and easy data retrieval. The practicality and accuracy of this testing approach have many applications, such as a quantitative tool for skating force assessment to aid athletes and coaches, as well as providing the means to examine other skill-specific dynamics.