The influence of squat depth on maximal vertical jump performance

An increase in the period over which a muscle generates force can lead to the generation of greater force and, therefore, for example in jumping, to greater jump height. The aim of this study was to examine the effect of squat depth on maximum vertical jump performance. We hypothesized that jump height would increase with increasing depth of squat due to the greater time available for the generation of muscular force. Ten participants performed jumps from preferred and deep squat positions. A computer model simulated jumps from the different starting postures. The participants showed no difference in jump height in jumps from deep and preferred positions. Simulated jumps produced similar kinematics to the participants' jumps. The optimal squat depth for the simulated jumps was the lowest position the model was able to jump from. Because jumping from a deep squat is rarely practised, it is unlikely that these jumps were optimally coordinated by the participants. Differences in experimental vertical ground reaction force patterns also suggest that jumps from a deep squat are not optimally coordinated. These results suggest there is the potential for athletes to increase jump performance by exploiting a greater range of motion.     

Assay validity of point-of-care platelet function tests in thrombocytopenic blood samples

IntroductionPoint-of-care (POC) platelet function tests are faster and easier to perform than in-depth assessment by flow cytometry. At low platelet counts, however, POC tests are prone to assess platelet function incorrectly. Lower limits of platelet count required to obtain valid test results were defined and a testing method to facilitate comparability between different tests was established.Materials and methodsWe assessed platelet function in whole blood samples of healthy volunteers at decreasing platelet counts (> 100, 80-100, 50-80, 30-50 and < 30 x10⁹/L) using two POC tests: impedance aggregometry and in-vitro bleeding time. Flow cytometry served as the gold standard. The number of platelets needed to reach 50% of the maximum function (ED₅₀) and the lower reference limit (ED_ref) were calculated to define limits of test validity.ResultsThe minimal platelet count required for reliable test results was 100 x10⁹/L for impedance aggregometry and in-vitro bleeding time but only 30 x10⁹/L for flow cytometry. Comparison of ED₅₀ and ED_ref showed significantly lower values for flow cytometry than either POC test (P value < 0.05) but no difference between POC tests nor between the used platelet agonists within a test method.ConclusionCalculating the ED₅₀ and ED_ref provides an effective way to compare values from different platelet function assays. Flow cytometry enables correct platelet function testing as long as platelet count is > 30 x10⁹/L whereas impedance aggregometry and in-vitro bleeding time are inconsistent unless platelet count is > 100 x10⁹/L.     

Revisiting the Relationship between Teacher Confirmation and Learning Outcomes: Examining Cultural Differences in Turkish,Chinese, and American Classrooms

This study investigates the relationship between teacher confirmation behaviors (i.e., responding to questions, demonstrating interest, interactive teaching style) and student learning outcomes (i.e., affective learning, student motivation) across three cultures: Turkey, China, and the United States. Results indicates the confirmation-learning relationship was significantly stronger in the United States and China than it was in Turkey. The findings from this study suggest that teacher confirmation is an effective teaching behavior that transcends cultures, yet the magnitude of its importance on student learning appears more relevant in America, and to a lesser extent in China, than it is in Turkey.     

Can high stakes national testing improve instruction: reexamining conventional wisdom

In this paper, the authors draw on recent international experience to assess the success of five propositions for how high stakes national testing can improve classroom instruction and, ultimately, raise student achievement. Findings indicate that testing can be an effective mechanism for improving instructional practice, but its success is not ensured. It has failed as often as it has succeeded, usually because those implementing the strategy failed to understand the intermediate conditions that had to be met for changes in test content, format, or use to have the desired impact on teachers' classroom practice.     

Reading Orthographically Strange Nonwords: Modelling Backup Strategies in Reading

The latest version of the connectionist dual process model of reading (CDP++.parser) was tested on a set of nonwords, many of which were orthographically strange (e.g., PSIZ). A grapheme-by-grapheme read-out strategy was used because the normal strategy produced many poor responses. The new strategy allowed the model to produce results similar to individual participants. Given that the strategy uses only simple information acquired in the normal course of learning, it shows that it is a plausible method for reading when the normal method fails and offers insight into how groups with low orthographic exposure might read.     

Becoming Whole: A Letter to a Young,Miseducated Black Teacher

The author uses this conceptual paper to present her personal narrative of transformation from miseducated (schooled) to educated (cultural broker) as a pretext to explore miseducation among young Black teachers. The author’s personal transformation comes in response to the neglect of teacher educators to attend to our few African American preservice teachers. Using a letter format, this paper places a particular focus on African American teachers and teacher educators, who agonize over how to transmit culture when they themselves have been miseducated.     

The Bologna process and its impact on higher education at Russia’s margins: the case of Kaliningrad

Embracing the Russian Federation since 2003, the Bologna process is no longer exclusively confined to western European countries. As early as 1999, Vladimir Putin declared the Russian exclave of Kaliningrad, wedged between Lithuania and Poland, as a potential pilot region for intensified cooperation between Russia and the EU on a number of policy areas, including higher education. In this paper, we study whether the Bologna process has served to underpin these ambitions. With a view to the EU, we will ask to what extent the European Union has proffered a model or directly influenced the path for transformation of Kaliningrad’s higher education system. We argue that a number of Kaliningrad-based actors in higher education have recognized the salience of European models and the need to work closely with partners from the EU, while Moscow only allows for marginal discretion in terms of Kaliningrad’s higher educational policy.