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Campbell AM Zanta CA Heyer LJ Kittinger B Gabric KM Adler L Schulz B 《CBE life sciences education》2006,5(4):332-339
We have developed a wet lab DNA microarray simulation as part of a complete DNA microarray module for high school students. The wet lab simulation has been field tested with high school students in Illinois and Maryland as well as in workshops with high school teachers from across the nation. Instead of using DNA, our simulation is based on pH indicators, which offer many ideal teaching characteristics. The simulation requires no specialized equipment, is very inexpensive, is very reliable, and takes very little preparation time. Student and teacher assessment data indicate the simulation is popular with both groups, and students show significant learning gains. We include many resources with this publication, including all prelab introductory materials (e.g., a paper microarray activity), the student handouts, teachers notes, and pre- and postassessment tools. We did not test the simulation on other student populations, but based on teacher feedback, the simulation also may fit well in community college and in introductory and nonmajors' college biology curricula. 相似文献
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Kerry S. Courney Laura Q. Rogers Kristin L. Campbell Jeff K. Vallance Christine M. Friedenreich 《北京体育大学学报》2016,39(2):40-48
摘要:今天的美国有1 400万的癌症存活者,其中的很多存活者中都接受了多种治疗,包括手术、放疗、化疗、靶向治疗等。这些治疗能够延长生存时间,但同时也会带来很多急慢性的副作用,危害健康,影响生活质量。体力活动(PA)与癌症生存这一领域发展迅速,主要研究PA对癌症患者的影响。基于该领域的研究进展,提出了以下10大研究问题:1)PA能够降低癌症复发风险、和/或提高存活吗?2)PA能够影响癌症治疗决策、完成率、和/或患者对治疗的反应吗?3)癌症存活者的最佳运动处方是什么?4)静坐少动行为对癌症存活者有何影响?5)癌症存活者最有效的体力活动干预方案是什么?6)哪些癌症会影响病人对PA的反应?7)癌症存活者进行体力活动时需要注意的安全问题有哪些?8)哪些具体的癌症症状可以由PA解决?9)对于癌症晚期患者,体力活动还有何作用?10)如何将体力活动研究结果转化到临床和社区肿瘤实践中来?上述问题的回答至关重要,这不仅关系到体力活动和癌症存活这一研究领域的发展,更重要的是,能够为每年数百万新诊断为癌症的病人、正在接受癌症治疗的病人、治疗结束处于恢复中的病人或是那些正在与晚期癌症抗争的病人带来福音。 相似文献
45.
Understanding the role of shaft stiffness in the golf swing 总被引:3,自引:3,他引:0
Theoretically, shaft stiffness can alter shot distance by increasing clubhead speed or altering clubhead orientation at impact.
A 3D forward dynamics model of a golfer and flexible club simulated the downswing. A genetic algorithm optimized the coordination
of the model’s muscles (four torque generators) to maximize clubhead speed. The maximum torque output and maximum rate of
torque development from the torque generators were varied to simulate the swing of golfers that generate different clubhead
speeds. Four shafts of varying stiffness (flexible, regular, stiff, and completely rigid) were entered into these simulations
to examine the role that shaft flexibility had on clubhead speed and orientation at impact. Shaft stiffness was found to have
a meaningful effect only on clubhead orientation (dynamic loft and dynamic close) at impact. There was no evidence to support
the premise that matching the stiffness properties of the shaft with the golfer would improve clubhead speed. 相似文献
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Guillaume Costalat Jeremy Coquart Ingrid Castres Fabrice Joulia Olivier Sirost Eric Clua 《Journal of sports sciences》2017,35(7):678-687
We investigated the oxygen-conserving potential of the human diving response by comparing trained breath-hold divers (BHDs) to non-divers (NDs) during simulated dynamic breath-holding (BH). Changes in haemodynamics [heart rate (HR), stroke volume (SV), cardiac output (CO)] and peripheral muscle oxygenation [oxyhaemoglobin ([HbO2]), deoxyhaemoglobin ([HHb]), total haemoglobin ([tHb]), tissue saturation index (TSI)] and peripheral oxygen saturation (SpO2) were continuously recorded during simulated dynamic BH. BHDs showed a breaking point in HR kinetics at mid-BH immediately preceding a more pronounced drop in HR (?0.86 bpm.%?1) while HR kinetics in NDs steadily decreased throughout BH (?0.47 bpm.%?1). By contrast, SV remained unchanged during BH in both groups (all P > 0.05). Near-infrared spectroscopy (NIRS) results (mean ± SD) expressed as percentage changes from the initial values showed a lower [HHb] increase for BHDs than for NDs at the cessation of BH (+24.0 ± 10.1 vs. +39.2 ± 9.6%, respectively; P < 0.05). As a result, BHDs showed a [tHb] drop that NDs did not at the end of BH (?7.3 ± 3.2 vs. ?3.0 ± 4.7%, respectively; P < 0.05). The most striking finding of the present study was that BHDs presented an increase in oxygen-conserving efficiency due to substantial shifts in both cardiac and peripheral haemodynamics during simulated BH. In addition, the kinetic-based approach we used provides further credence to the concept of an “oxygen-conserving breaking point” in the human diving response. 相似文献
48.
Recurve archery is an Olympic sport that requires extreme precision, upper body strength and endurance. The purpose of this research was to quantify how postural stability variables both pre- and post-arrow release, draw force, flight time, arrow length and clicker reaction time, collectively, impacted on the performance or scoring outcomes in elite recurve archery athletes. Thirty-nine elite-level recurve archers (23 male and 16 female; mean age?=?24.7?±?7.3 years) from four different countries volunteered to participate in this study prior to competing at a World Cup event. An AMTI force platform (1000Hz) was used to obtain centre of pressure (COP) measurements 1s prior to arrow release and 0.5s post-arrow release. High-speed footage (200Hz) allowed for calculation of arrow flight time and score. Results identified clicker reaction time, draw force and maximum sway speed as the variables that best predicted shot performance. Specifically, reduced clicker reaction time, greater bow draw force and reduced postural sway speed post-arrow release were predictors of higher scoring shots. It is suggested that future research should focus on investigating shoulder muscle tremors at full draw in relation to clicker reaction time, and the effect of upper body strength interventions (specifically targeting the musculature around the shoulder girdle) on performance in recurve archers. 相似文献
49.
Eric Ma 《Inter-Asia Cultural Studies》2013,14(2):187-200
The paper attempts to work out the link between the structuring of the public domain and hegemonic masculinities in contemporary Kerala, South India. Using the debates around an incident of sexual harassment that happened in 1999, it argues for a conjunctural understanding of the contemporary where various events and moments in history are replayed through narrativization and popular memory. The paper goes on to analyse the debates around the incident that produce a ‘narrative public domain’, to foreground the various notions of masculinity that construct and structure it in relation to notions of female sexuality and changing structures of family. These notions of masculinity could be, the paper argues, a starting point for a historical inquiry into Kerala's modernity – an inquiry that would throw light on the past and the ways in which the contemporary is produced through its historical legacies. 相似文献
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