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21.
Understanding the biological feeding strategy and characteristics of a microorganism as an actuator requires the detailed and quantitative measurement of flow velocity and flow rate induced by the microorganism. Although some velocimetry methods have been applied to examine the flow, the measured dimensions were limited to at most two-dimensional two-component measurements. Here we have developed a method to measure three-dimensional two-component flow velocity fields generated by the microorganism Vorticella picta using a piezoscanner and a confocal microscope. We obtained the two-component velocities of the flow field in a two-dimensional plane denoted as the XY plane, with an observation area of 455×341 μm2 and the resolution of 9.09 μm per each velocity vector by a confocal microparticle image velocimetry technique. The measurement of the flow field at each height took 37.5 ms, and it was repeated in 16 planes with a 2.50 μm separation in the Z direction. We reconstructed the three-dimensional two-component flow velocity field. From the reconstructed data, the flow velocity field [u(x,y,z),v(x,y,z)] in an arbitrary plane can be visualized. The flow rates through YZ and ZX planes were also calculated. During feeding, we examined a suction flow to the mouth of the Vorticella picta and measured it to be to 300 pl∕s. 相似文献
22.
Sumiko Asai 《Journal of Media Economics》2013,26(2):81-101
This article analyzes the sales patterns of audio recordings in the Japanese popular music market using the Bass model and its restricted model. First, the results of this investigation show that the majority of recent hit music was sold in the early stage of the sales cycle, and that the timing of purchase has shifted toward the time of release during the period from 1980 to 2005. Second, audio recordings featuring debut artists and unpopular artists sold slowly, compared with the audio recordings featuring popular artists. Third, sales of audio recordings released by independent record companies have also become concentrated in the early stage. 相似文献
23.
Welber Marinovic Andrea Michele Freudenheim Cristina Akiko Iizuka Luiz Henrique Porto Vilani 《体育科研》2005,26(3):90-94
本研究旨在调查当高水平乒乓球运动员被要求对付不同状态来球时,如何调整他们的动作.研究对象与方法前巴西国家队高水平乒乓球男女运动员7名,均为右手持拍.运动员(平均年龄27.85±5.36岁、训练年限平均为19.14±5.24年,运动员身体状况良好,每周训练3次.运动员分别在4种状况下,对发球机发出的乒乓球进行正手击球(1)两次反弹(一次过网前一次过网后)的上旋球;(2)两次反弹的侧旋球;(3)一次反弹(过网后)的上旋球;(4)一次反弹的侧旋球.研究结果(1)乒乓球运动员采用包括动作的绝对和相对的修正以促进正手对击球的适应;(2)动作修正的本质受不同状况的约束;(3)细微动作(触球和随拍)比宏观动作(准备姿态和向前挥拍)更容易受外界状况的影响.分析与讨论(1)回击一次和两次反弹的侧旋球,运动员几乎不用调整,但侧旋球会造成成功率不高.在引拍、迎球挥拍阶段动作模式没有改变,但球拍触球、随势挥拍阶段稍有不同,此动作有利于还原部分;(2)击球动作前的选位和对手的动作趋势也会影响动作模式,但变化却是使整个动作结构的改变. 相似文献
24.
Akiko Yamazaki 《Children‘s Literature in Education》2002,33(1):53-62
Translation of a literary work is never an automatic process but always poses many problems caused by the differences between two linguistic and cultural systems. The difficulty seems to be enhanced if the work to be translated is for children who have little knowledge about the culture from which the text originates. At least, that must be the idea behind the practice of replacing foreign names with familiar ones, a practice still common in English and German translations. The present argument is that this change not only shows a lack of respect toward other cultures but also deprives child readers of the chance to realize the wealth of cultural diversity that surrounds them. 相似文献
25.
博客,已经存在了很长时间.但是它的主要用途似乎只是用于一些个人对事件、对自己、对自己的粉丝们发表一些满足人们猎奇心理的文章.对于它的商用价值,似乎很少有涉及,在这一点上,精明的日本人又一次走在了潮流的前头.…… 相似文献
26.
Akiko Yasuike 《Journal of Latinos & Education》2019,18(1):42-52
Based on 29 in-depth interviews with undocumented Latino college students and graduates in Southern California, this study explores how academic high achievers obtain the information, resources, and emotional support they need to achieve college-student status. The study highlights the importance of the programs offered by schools and nonprofit organizations to compensate for undocumented Latino students’ lack of social capital and their parents’ lack of human capital. Forging a trusting relationship with teachers and/or counselors remains crucial for navigating the unique application process for undocumented students and for identifying private funding sources. 相似文献
27.
Christopher J. Rybak Amy Leary Akiko Marui 《International journal for the advancement of counseling》2001,23(1):7-19
The Resiliency Wheel provides interview guidance tocounselors in training. The interview format providesenough structure for beginning counselors to feelcomfortable with the questions, but offers flexibilityto more experienced counselors as they formulate newquestions as the client's story unfolds. TheResiliency Wheel provides a way for counselors to linkindividual client strengths while drawing from thefollowing factors: person, family, community, spirit,and culture. A diagram of the resiliency wheel can beused to record client information. The questionsallow the counselor in training to become familiarwith other cultures and worldviews. This awarenessincreases a counselor's cultural sensitivity andempathy around issues of oppression, discrimination,and racism due to one's ethnicity. The studentcounselor is given the opportunity to ask specificquestions about a culture and realize the differences,but also the similarities between the counselor andthe client. The Resiliency Wheel assists thecounselor to develop a holistic understanding of theclient and to be able to reflect this understanding tothe client visually as well as verbally. Theinterview process in itself can bring about a deepersharing of client identity and experience,contributing to the bond between client and counselor. 相似文献
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29.
This paper uses international data from a range of sources, principally the 2013 round of the Teaching and Learning International Survey (TALIS 2013), to provide new information on classroom disciplinary climate in secondary schools in England. The paper advances the literature in three distinct ways. Firstly, the data show that teachers in England perceive that there is considerable disruption in their classrooms. While some reports, especially from official sources, have suggested that classroom disruption is minimal in schools in England that does not seem plausible given these results from TALIS. Secondly, since TALIS contains comparable data for over 30 countries, the results for England can be set in a wider context. Reports in the media frequently highlight pupil disruption and suggest that classroom climate tends to be worse in England than in many other countries. In fact what emerges from the international comparison is that, on each of the items measuring classroom climate in TALIS 2013, the results for England were somewhat better than both the all‐country average and the average for a group of European comparators. Thirdly, the survey also includes a range of information about the school in which the teacher worked, the pupils which they taught, and the teachers themselves. We draw on this data to investigate which school‐level characteristics, teacher attributes, and characteristics of pupils in the classroom, were associated with favourable classroom climate in England. While some commentators have focused exclusively on school‐level factors, we emphasise the importance of within‐school variation. 相似文献
30.
When the boundary layer of a sports ball undergoes the transition from laminar to turbulent flow, a drag crisis occurs whereby
the drag coefficient (C
d) rapidly decreases. However, the aerodynamic properties and boundary-layer dynamics of a soccer ball are not yet well understood.
In this study we showed that the critical Reynolds number (Re
crit) of soccer balls ranged from 2.2 × 105 to 3.0 × 105. Wind-tunnel testing, along with visualisation of the dynamics of the boundary layer and the trailing vortex of a ball in
flight, demonstrated that both non-spinning and spinning (curved) balls had lowC
d values in the super-critical region. In addition, theRe
crit values of the soccer balls were lower than those of smooth spheres, ranging from ∼ 3.5 × 105 to 4.0 × 105, due to the effects of their panels. This indicated that the aerodynamic properties of a soccer ball were intermediate between
those of a smooth ball and a golf ball. In a flow visualisation experiment, the separation point retreated and theC
d decreased in a super-critical regime compared with those in a sub-critical regime, suggesting a phenomenon similar to that
observed in other sports balls. With some non-spinning and spinning soccer balls, the wake varied over time. In general, the
high-frequency component of an eddy dissipated, while the low-frequency component increased as the downstream vortex increased.
The causes of the large-scale fluctuations in the vortex observed in the present study were unclear; however, it is possible
that a ‘knuckle-ball effect’ of the non-rotating ball played a role in this phenomenon. 相似文献