Beyond city expansion:multi-scale environmental impacts of urban megaregion formation in China

Environmental degradation caused by rapid urbanization is a pressing global issue.However,little is known about how urban changes operate and affect environment...     

Is Transracial the Same as Transgender? The Utility and Limitations of Identity Analogies in Multicultural Education

In June 2015, Melissa Harris-Perry infamously analogized the possibility of trans-Black identity to the reality of transgender identity. Such analogies happen often and are used mostly for the benefit of learning about a less familiar form of identity. Building from a recent article by Suthakaranm, Filsinger, and White (2013 Suthakaran, V., Filsinger, K., &; White, B. (2013). Using analogies as an experiential learning technique in multicultural education. Multicultural Perspectives, 15(2), 92–97.[Taylor &; Francis Online] , [Google Scholar]) that presented a compelling argument for the use of analogies as an experiential learning tool in multicultural education, we advance the conversation by distinguishing a particular form of analogies: identity analogies. We explore the benefits and challenges of utilizing identity analogies as a tool for multicultural educators within U.S. higher education.     

Statistical modelling of knee valgus during a continuous jump test

Landing with the knee in a valgus position is recognized as a risk factor for anterior cruciate ligament (ACL) injury. Using linear and non-linear regression analyses, the purpose of this study was to examine the correlation between two-dimensional (2D) knee valgus and three-dimensional (3D) knee kinematics measured during a jump landing task. Twenty-eight female collegiate athletes participated. All participants were required to perform a continuous jump test. The average maximum angles of abduction and internal tibial rotation during landing were measured using the Point Cluster Technique. Average peak knee valgus angle was measured using a 2D approach. Linear and non-linear regression analyses between 2D valgus and 3D knee abduction, and between 2D valgus and 3D internal tibial rotation, were performed. The R2 value between 2D valgus and 3D knee abduction was significantly different from zero and had a moderate correlation for all models, whereas the R2 value between 2D valgus and 3D internal tibial rotation was not significantly different from zero. The 2D approach could be used to screen a specific group of individuals for risk of ACL injury; however, using frontal plane 2D analysis of valgus motion to evaluate internal tibial rotation is not advised.     

Repeated retention testing effects do not generalize to a contextual interference protocol

Three experiments examined repeated retention testing effects in a contextual interference (CI) protocol. Retention was assessed at 10 min and 24 hr following acquisition or at just 24-hr for the one-test conditions. Experiments 1 and 2 used speeded-response key-pressing tasks. Dependent measures were total time and errors. Experiment 3 used sequential-timing tasks. Dependent measures were absolute error and absolute constant error Results revealed CI effects in each experiment. Repeated retention testing effects were not found in Experiments 1 and 3. Experiment 2 revealed superior performance by the two-test condition compared to the one-test condition. This result was qualified by possible practice effects during the 10-min test. It was concluded that repeated retention testing does not present problems for most studies of CI.     

Nutritional strategies to optimize training and racing in middle-distance athletes

Middle-distance athletes implement a dynamic continuum in training volume, duration, and intensity that utilizes all energy-producing pathways and muscle fibre types. At the centre of this periodized training regimen should be a periodized nutritional approach that takes into account acute and seasonal nutritional needs induced by specific training and competition loads. The majority of a middle-distance athlete's training and racing is dependant upon carbohydrate-derived energy provision. Thus, to support this training and racing intensity, a high carbohydrate intake should be targeted. The required energy expenditure throughout each training phase varies significantly, and thus the total energy intake should also vary accordingly to better maintain an ideal body composition. Optimizing acute recovery is highly dependant upon the immediate consumption of carbohydrate to maximize glycogen resynthesis rates. To optimize longer-term recovery, protein in conjunction with carbohydrate should be consumed. Supplementation of beta-alanine or sodium bicarbonate has been shown to augment intra- and extracellular buffering capacities, which may lead to a small performance increase. Future studies should aim to alter specific exercise (resistance vs. endurance) and/or nutrition stimuli and measure downstream effects at multiple levels that include gene and molecular signalling pathways, leading to muscle protein synthesis, that result in optimized phenotypic adaptation and performance.     

Biomechanics of aggressive inline skating: landing and balancing on a grind rail

Currently, only epidemiological injury data have been reported for the new extreme sport of aggressive inline skating, or trick skating. No studies have examined the biomechanics of this sport, which involves repetitive jumping and landing from railings, ramps, and ledges, often over 1 m in height. We present results of a pilot study that examined the effect of skater experience and lower extremity biomechanics on energy absorption ability, and observed balance strategies used during two basic tricks. In these tricks, the skater jumps onto an elevated rail and maintains balance while standing in a single position (stall) or sliding along the rail (grind). Lower extremity joint kinematics, impact force characteristics, and general movement behaviours were examined during landing and balance phases. Ten male skaters performed ten stalls and ten frontside grinds on an instrumented grind rail, capable of measuring vertical force. Vertical impact force was found to decrease with increasing skater experience in stalls (r = -0.84, P = 0.002) and grinds (r = -0.84, P = 0.009). This might imply that less-experienced skaters are (subconsciously) more concerned about maintaining balance than refining technique to minimize impact force. Similar to drop landing experiments, peak impact force decreased with increasing knee flexion during stalls (r = -0.65, P = 0.04). During stalls, skaters demonstrated classic balance maintenance strategies (ankle, hip, or multi-joint) depending on trick length. During grinds, skater centre of mass never passed over the rail base of support, suggesting the use of momentum produced from obliquely approaching the rail.