Increasing hip and knee flexion during a drop-jump task reduces tibiofemoral shear and compressive forces: implications for ACL injury prevention training

Although most ACL injury prevention programmes encourage greater hip and knee flexion during landing, it remains unknown how this technique influences tibiofemoral joint forces. We examined whether a landing strategy utilising greater hip and knee flexion decreases tibiofemoral anterior shear and compression. Twelve healthy women (25.9 ± 3.5 years) performed a drop-jump task before and after a training session (10–15 min) that emphasised greater hip and knee flexion. Peak tibiofemoral anterior shear and compressive forces were calculated using an electromyography (EMG)-driven knee model that incorporated joint kinematics, EMG and participant-specific muscle volumes and patella tendon orientation measured using magnetic resonance imaging (MRI). Participants demonstrated a decrease in peak anterior tibial shear forces (11.1 ± 3.3 vs. 9.6 ± 2.7 N · kg^?1; P = 0.008) and peak tibiofemoral compressive forces (68.4 ± 7.6 vs. 62.0 ± 5.5 N · kg^?1; P = 0.015) post-training. The decreased peak anterior tibial shear was accompanied by a decrease in the quadriceps anterior shear force, while the decreased peak compressive force was accompanied by decreased ground reaction force and hamstring forces. Our data provide justification for injury prevention programmes that encourage greater hip and knee flexion during landing to reduce tibiofemoral joint loading.     

Effects of Applying Different Time Limits to a Proposed GRE Writing Test

In order to determine the role of time limits on both test performance and test validity, we asked approximately 300 volunteers–prospective graduate students–to each write two essays–one in a 40-minute time period and the other in 60 minutes. Analyses revealed that, on average, test performance was significantly better when examinees were given 60 minutes instead of 40. However, there was no interaction between test-taking style (fast vs. slow) and time limits. 'That is', examinees who described themselves as slow writers/test takers did not benefit any more (or any less) from generous time limits than did their quicker counterparts. In addition, there was no detectable effect of different time limits on the meaning of essay scores, as suggested by their relationship to several nontest indicators of writing ability.     

Implicit Theories of Personality and Attributions of Hostile Intent: A Meta‐Analysis,an Experiment,and a Longitudinal Intervention

Past research has shown that hostile schemas and adverse experiences predict the hostile attributional bias. This research proposes that seemingly nonhostile beliefs (implicit theories about the malleability of personality) may also play a role in shaping it. Study 1 meta‐analytically summarized 11 original tests of this hypothesis (N = 1,659), and showed that among diverse adolescents aged 13–16 a fixed or entity theory about personality traits predicted greater hostile attributional biases, which mediated an effect on aggressive desires. Study 2 experimentally changed adolescents' implicit theories toward a malleable or incremental view and showed a reduction in hostile intent attributions. Study 3 delivered an incremental theory intervention that reduced hostile intent attributions and aggressive desires over an 8‐month period.     

Making Sense of Bali: Unintended outcomes of study abroad programs

Study abroad programmes for teacher education students are increasingly being evaluated to determine their effectiveness in achieving intended outcomes. There is a danger, however, that such evaluations will ignore valuable but unintended and serendipitous outcomes of such programmes. This paper investigates an example of such an outcome, the development of a critical perspective towards media constructions of ‘otherness’. In 2002 a group of Australian teacher education students undertook an intensive in‐country Indonesian language programme. The course included mornings of formal immersion language classes and afternoons of cultural experiences with local students. Throughout and following the programme the students were interviewed and wrote about their changing perceptions of Indonesia and the implications of the experience for their professional development. Soon after their return Indonesian–Australian relations were challenged by the terrorist attack in the tourist heart of Bali. Two hundred and two people, including many Australian tourists, were killed in the bomb blast. In some cases the students were personally acquainted with Australian victims. As part of their reflection upon their in‐country experience the students were asked to comment upon whether, and in what ways, the Bali bombings might have affected their perceptions of Indonesia. The students were highly critical of the ethnocentric and stereotyped way in which the Australian media depicted Indonesians in their reporting of the bombing. These students were concerned with the effect that such media constructions might have upon Australian attitudes towards Indonesia and were prepared to challenge such media constructions in the classroom.     

Teachers and their Books

Too often there is far too large a gap between the sort of literature recommended by the English teacher and the normal reading tastes both of children and adults (W. Stewart, 1950).