Diversity Knowledge in Science Teacher Education-Translating Concept to Instruction: An Example Specific to African Americans

Science education reforms promote access to quality science education for all students. Outcome disparities in various measures indicate that such access remains elusive for African Americans. Cultural incongruence is one among many explanations for this previously described inaccessibility. The intent of this article is not to report additional research findings, but to translate the information provided in the literature into an instructional form that science teacher educators can employ in the preparation of prospective science teachers or the further development of practicing ones. Pivoting around a role play, the authors discuss communication within African American communities, its incongruence with the discourse patterns typically valued and reinforced in school science, and the importance of such knowledge for science teacher educators. Lieutenant Colonel Stephanie Foster is now product manager in the U.S. Army Research Development and Engineering Command.

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Muscle co-activation and its influence on running performance and risk of injury in elite Kenyan runners

The relationship between muscle co-activation and energy cost of transport and risk of injury (initial loading rate and joint stiffness) has not been jointly studied. Fourteen elite Kenyan male runners were tested at two speeds (12 and 20 km · h^?1), where oxygen consumption, kinematic, kinetic and electromyography were recorded. Electromyography of seven lower limb muscles was recorded. Pre-activation and ground contact of agonist:antagonist co-activation was determined. All muscles displayed higher activity during pre-activation except rectus femoris (RF). Conversely, no differences were found during ground contact except for higher biceps femoris (BF) at 20 km · h^?1. Knee stiffness was correlated to RF–BF co-activation during both pre-activation and ground contact at both running speeds. However, energy cost of transport was only positively correlated to the above-mentioned muscle pairs at 20 km · h^?1 (r = 0620, P = 0.032; r = 0.682, P = 0.015, respectively). These findings emphasise the influence of neuromuscular control and performance and its support to musculoskeletal system to optimise function and modulate risk of injury. Further, neuromuscular activity during terminal swing is also important and necessary to execute and maintain performance.     

Drinking guidelines for exercise: what evidence is there that athletes should drink "as much as tolerable", "to replace the weight lost during exercise" or "ad libitum"?

The most recent (1996) drinking guidelines of the American College of Sports Medicine (ACSM) propose that athletes should drink "as much as tolerable" during exercise. Since some individuals can tolerate rates of free water ingestion that exceed their rates of free water loss during exercise, this advice has caused some to overdrink leading to water retention, weight gain and, in a few, death from exercise-associated hyponatraemic encephalopathy. The new drinking guidelines of the International Olympic Committee (IOC), recently re-published in this Journal, continue to argue that athletes must drink enough to replace all their weight lost during exercise and to ingest sodium chloride since sodium is "the electrolyte most critical to performance and health". In this rebuttal to that Consensus Document, I argue that these new guidelines, like their predecessors, lack an adequate, scientifically proven evidence base. Nor have they been properly evaluated in appropriately controlled, randomized, prospective clinical trials. In particular, these new guidelines provide erroneous recommendations on five topics. If novel universal guidelines for fluid ingestion during exercise are to be promulgated by important international bodies including the IOC, they should first be properly evaluated in appropriately controlled, randomized, prospective clinical trials conducted under environmental and other conditions that match those found in "out-of-doors" exercise. This, and the potential influence of commercial interests on scientific independence and objectivity, are the two most important lessons to be learned from the premature adoption of those 1996 ACSM drinking guidelines that are not evidence-based. These concerns need to be addressed before the novel IOC guidelines are accepted uncritically. Otherwise the predictable consequences of the premature adoption of the 1996 ACSM guidelines will be repeated.     

What limits [V(·)]O(2max)? A symposium held at the BASES Conference, 6 September 2010

Three modern views about the factors limiting oxygen uptake in healthy humans are set against the original (early 1920s) concept of A. V. Hill and colleagues. The majority view for most of the intervening time has been that cardiac output is the essential limiting function. Among recent research in support of this contention is that, in quadrupeds, pericardiectomy, which allows greater diastolic filling, elevates maximum oxygen uptake; however, the relevance to bipedal exercise can be questioned. In any case, algebraic analyses of model systems indicate that all identifiable stages on the oxygen transport pathway, from pulmonary diffusion to oxidative phosphorylation in skeletal muscle mitochondria, materially influence maximum uptake. Thus, if a high cardiac output is to be of benefit, all the other steps must function better too. Nevertheless, these two viewpoints concur that the limit to maximum oxygen uptake is somatic. In contrast, there are strong indications that at altitudes where oxygen availability is about half that at sea level, cerebral oxygenation is a limiting factor, and some recent experiments raise the possibility that it might be a substantial influence at sea level also. Clearly, consensus cannot yet be reached on the question posed in the title.     

Teaching boys: towards a theory of gender-relevant pedagogy

This article calls attention to the social and educational challenges facing boys and men around the world. Next, it highlights how the outcomes for males of African descent across the Americas, in particular the USA, are especially troubling. Moreover, a critique is presented about the recruitment campaigns that see increasing the number of Black male teachers as an elixir for improving the crisis facing Black boys. Then, the article focuses on the intersection of race and gender and reframes the discussion around improving the deleterious school outcomes facing Black boys by shifting the conversation to exploring how educators' socialised views around gender influence the ways in which they teach boys. Finally, the article provides practical applications for designing a curriculum that is gender relevant.     

Not Babysitting: Work Stress and Well-Being for Family Child Care Providers

Family child care providers contend with a number of work stressors related to the dual roles of operating a small business and providing child care in their home. Research has documented many sources of work related stress for family child care providers; however, research examining family child care providers’ experiences outside of the lens of quality of care and child outcomes is dated and scant. This study consisted of three focus groups of 11 family child care providers who shared their perspectives on work related stressors and well-being. Many of the study findings were congruent with previous research in the field; however, a key finding in this study was the importance of family child care providers to assert and establish a professional identity to mitigate work related stress. Recommendations and strategies to assist family child providers in constructing a professional identity are discussed.     

Assessing the Impact of a Business Communication Simulation on Students' Self-Perceptions

This article examines whether participation in a business communication simulation significantly influences students' perceptions of their business communication behaviors. Results revealed several significant differences between students' pre- and post scores. Students reported significantly higher post scores in 4 of 5 of the examined categories, including message construction, message delivery, critical analysis, and collaboration. These findings suggest that participation in the simulation positively impacts students' estimations of their business communication competencies. Possible explanations and implications behind these findings are discussed. Future research directions are proposed.     

Children's Cross‐Ethnic Relationships in Elementary Schools: Concurrent and Prospective Associations Between Ethnic Segregation and Social Status

This study examined whether ethnic segregation is concurrently (fall) and prospectively (fall to spring) associated with social status among 4th‐ and 5th‐grade African American and European American children (n = 713, ages 9–11 years). Segregation measures were (a) same‐ethnicity favoritism in peer affiliations and (b) cross‐ethnicity dislike. Social status measures were same‐ and cross‐ethnicity peer nominations of acceptance, rejection, and cool. Among African Americans, fall segregation predicted declines in cross‐ethnicity (European American) acceptance and same‐ethnicity rejection, and increases in same‐ethnicity acceptance and perceived coolness. For European American children, fall segregation predicted declines in cross‐ethnicity (African American) acceptance and increases in cross‐ethnicity rejection. Results indicate that segregation induces asymmetric changes in social status for African American and European American children.