首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   21篇
  免费   0篇
教育   5篇
科学研究   4篇
体育   10篇
文化理论   1篇
信息传播   1篇
  2022年   1篇
  2020年   1篇
  2019年   2篇
  2018年   3篇
  2017年   3篇
  2016年   1篇
  2013年   4篇
  2012年   1篇
  2011年   3篇
  2010年   1篇
  2002年   1篇
排序方式: 共有21条查询结果,搜索用时 446 毫秒
1.
Oxygen and glucose supply is one of the important factors for the growth and viability of the cells in cultivation of tissues, e.g., spheroid, multilayered cells, and three-dimensional tissue construct. In this study, we used finite element methods to simulate the flow profile as well as oxygen and glucose supply to the multilayered cells in a microwell array chip for static and perfusion cultures. The simulation results indicated that oxygen supply is more crucial than glucose supply in both static and perfusion cultures, and that the oxygen supply through the wall of the perfusion culture chip is important in perfusion cultures. Glucose concentrations decline with time in static cultures, whereas they can be maintained at a constant level over time in perfusion cultures. The simulation of perfusion cultures indicated that the important parameters for glucose supply are the flow rate of the perfusion medium and the length of the cell culture chamber. In a perfusion culture chip made of oxygen-permeable materials, e.g., polydimethylsiloxane, oxygen is hardly supplied via the perfusion medium, but mainly supplied through the walls of the perfusion culture chip. The simulation of perfusion cultures indicated that the important parameters for oxygen supply are the thickness of the flow channel and the oxygen permeability of the walls of the channel, i.e., the type of material and the thickness of the wall.  相似文献   
2.
We examined the hypothesis that congruence between motivational dominance and state results in optimal psychological responses and performance during exercise. Twenty participants (10 telic dominant and 10 paratelic dominant) rated their stress at 5 min intervals as they cycled on an ergometer at gas exchange threshold for 30 min in both telic and paratelic state manipulated conditions. Participants then performed a test to exhaustion at a resistance equivalent to 110% of VO(2max). The hypothesized interaction between condition and dominance was significant for internal tension stress, as paratelic dominants were more stressed than telic dominants when exercising in the telic state and telic dominants were more stressed than paratelic dominants when exercising in the paratelic state. Similarly, the condition × dominance interaction for internal stress discrepancy was significant, as paratelic dominants reported greater internal stress discrepancy exercising in the telic compared with the paratelic state. Findings are discussed in relation to the application of reversal theory for understanding stress responses during aerobic exercise.  相似文献   
3.
To study an environmental or biological solution, it is essential to separate its constituents. In this study, a 3D-deformable dynamic microfilter was developed to selectively separate the target substance from a solution. This microfilter is a fine metallic nickel structure fabricated using photolithography and electroplating techniques. It is gold-coated across its entire surface with multiple slits of 10–20 μm in width. Its two-dimensional shape is deformed into a three-dimensional shape when used for fluid separation due to hydrodynamic forces. By adjusting the pressure applied to the microfilter, the size of the gap created by deformation can be changed. To effectively isolate the target substance, the relationship between the solution flow rate and the extent of microfilter deformation was investigated. The filtration experiments demonstrated the microfilter’s ability to isolate the target substance with elastic deformation without undergoing plastic deformation. Additionally, modification of the microfilter surface with nucleic acid aptamers resulted in the selective isolation of the target cell, which further demonstrates the potential application of microfilters in the isolation of specific components of heterogeneous solutions.  相似文献   
4.
Creativity is considered a human characteristic; creative endeavors, including automatic story generation, have been a major challenge for artificial intelligences. To understand how humans create and evaluate stories, we (1) construct a story dataset and (2) analyze the relationship between emotions and story interestingness. Given that understanding how to move readers emotionally is a crucial creative technique, we focus on the role of emotions in evaluating reader satisfaction. Although conventional research has highlighted emotions read from a text, we hypothesize that readers’ emotions do not necessarily coincide with those of the characters. The story dataset created for this study describes situations surrounding two characters. Crowdsourced volunteers label stories with the emotions of the two characters and those of readers; we then empirically analyze the relationship between emotions and interestingness. The results show that a story’s score has a stronger relationship to the readers’ emotions than the characters’ emotions.  相似文献   
5.
ABSTRACT

This article examines the notion of interculturality in face-to-face, multilingual, ordinary interactions. The focus is on how participants perform constituent actions by reference to members’ normative expectations to a specific membership category. Employing ethnomethodology and conversation analysis, this article elucidates interculturality is an interactional achievement in interaction. More specifically, I describe interactional practices for doubting others’ nationality and accounting for doubts accomplished by particular interactional practices in a specific interactional position. Analyzing these interactional contingencies produced by participants demonstrates that members’ practices to make interculturality relevant in a temporal unfolding of the activity and shows how they reflexively use interculturality as a resource for constituent actions. This study contributes to the existing literature on the interactional construction of international and intercultural communication, and on the situated, sequential, and embodied organization of interculturality.  相似文献   
6.
Reading Comprehension tests are commonly used to assess the degree to which people comprehend what they read. This is why we work with the hypothesis that it is reasonable to use these tests to assess the degree to which a machine “comprehends” what it is reading. In this work, we evaluate Question Answering systems using Reading Comprehension tests from exams to enter University. This article analyses the datasets generated, the kind of inferences required, the methodology followed in three evaluation campaigns, the approaches presented by participants and current results. Besides, we study the evolution of systems and the main lessons learned in this evaluation process. We also show how current technologies are unable to pass university-entrance exams. This is because these tests require a deep understanding of texts, as well as detecting the similar meaning of phrases with different words. Future directions focused on these ideas seem more promising than including a massive amount of data for training systems, what has allowed systems to obtain outstanding results in Reading Comprehension tests with more straightforward questions. We think this study helps to increase the knowledge about how to develop better Question Answering systems.  相似文献   
7.
Athletics     
The purpose of this study was to determine primary factors that contribute to the magnitude of the maximum torsional moment on the tibia during running based on information from three‐dimensional shank kinematics and ground reaction forces. Eight male subjects were asked to run along a straight track at 5.0 m s‐1. Data were collected using two high‐speed cameras and a force platform. Each subject's left foot and tibia were modelled as a system of coupled rigid bodies. First, net axial moments acting at both ends of the tibia were calculated using inverse dynamics. Then the tibial torsional moment was determined from the quasi‐equilibrium balance of the net tibial axial moments. Our results showed considerable inter‐individual variations for the tibial torsional moment during the stance phase of running. The maximum torsional moment reflecting external rotational loading of the proximal tibia was significantly correlated with the outward tilt angle of the shank in the frontal plane (r = 0.78, p <0.05) and with the vertical force of ground reaction (r = 0.70, p <0.05). In conclusion, lowering tibial torsional loading by interventions based on the present findings may lead to the reduction of running injuries that occur in athletes’ tibiae.  相似文献   
8.
Although the methods for medical education continue to evolve due to the development of medicines, the cadaver dissection course still plays a fundamental role. The cadaver dissection course allows students to learn to handle instruments correctly while actively exploring three-dimensional anatomy. However, dissection comes with the risk of accidental injury. In recent years, the number of classes offered for the cadaver dissection course has decreased while the amount of knowledge required in clinical medicine has increased. Simulation-based education (SBE) has been proven to be an effective educational method that enhances the development of practical skills by integrating learners' knowledge and skills. This study aimed to investigate the effect of SBE as a preparatory education course when taken prior to a medical student's enrollment in the cadaver dissection course. In the present study, an SBE assuming practical cadaver dissection course was performed in the Clinical Simulation Center. The frequency of injury rates per 1000 h of cadaver dissection course was significantly less in 2017 and 2018 compared to that in 2016. Two years after the implementation of the SBE, average student self-efficacy scores and written examination scores significantly increased, whereas self-contentment scores were relatively unchanged. The results showed that the implementation of SBE decreased the incidence of injuries and improved students' overall self-efficacy scores and increased acquisition of knowledge evident on written examination score. Therefore, SBE as a preparatory education course may effectively promote the combined development of dissection skills and anatomical knowledge in the subsequent fundamental cadaver dissection course.  相似文献   
9.
An assembly robot needs to be capable of executing an assembly task robustly under various uncertainties.To attain this goal,we use a task sequence tree model originally proposed for manual assembly.This model regards an assembly task under uncertainties as a transformation of the contact state concept.The concept may contain several contact states with probabilities but these are transformed through a series of task elements into the contact state concept having only the goal state at the end.The transformed contact state concept can be classified according to the terminal condition of each task element.Thus,the whole assembly task can be designed as a tree-shaped contingent strategy called a task sequence tree.This paper proposes a systematic approach for reconfiguring a task sequence tree model for application to a robotic assembly task.In addition,by taking a 2D peg-in-hole insertion task to be performed by a robot equipped with a force sensor as an example,we confirm that the proposed approach can provide a robust motion strategy for the task and that the robot can actually execute the task robustly under bounded uncertainty according to the strategy.  相似文献   
10.
This study evaluated the association between the frequency of tennis play and executive function in children and adolescents. One hundred and six junior tennis players (6–15 years old) participated in this study. Executive function, including inhibitory control, working memory, and cognitive flexibility were evaluated at rest. Females showed better inhibitory control and cognitive flexibility than males. In males, more frequent tennis play was associated with higher basic processing speed and inhibitory control after controlling for age, gender, body mass index (BMI), and tennis experience. More frequent tennis play was associated with better working memory in both males and females after controlling for age, gender, BMI, and tennis experience. Furthermore, longer tennis experience was related to better cognitive flexibility in males after controlling for age, gender, BMI, and frequency of tennis play. These findings suggest that tennis play is associated with the development of three foundational aspects of executive function (i.e. inhibitory control, working memory, cognitive flexibility). Especially, frequent participation in tennis play is related to better inhibitory control and working memory, while longer experience of tennis play is associated with better cognitive flexibility. Although development of inhibitory control and cognitive flexibility is slower in males than in females, the associations between tennis play and inhibitory control and cognitive flexibility appear to be larger in males than in females.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号