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41.
42.

Key points

  • Instructions to authors about submitting papers for publication vary hugely – from none at all to whole handbooks.
  • Online submission systems have not reduced the complexity of submission and may have increased the work of authors.
  • Electronic submission processes do not appear to have been adequately ‘road tested’ with authors.
  • Some publishers are introducing more flexible submission rules that may help authors.
  相似文献   
43.
In order to study the influence on memorization of external inputs as well as children’s own strategies, we examined both parental discourses in terms of distancing (Sigel, 1970) and spontaneous rehearsal by children during a memory task. Our aim was to assess the influence of each factor for children between 3 and 5 years of age. In our study of 72 parent-child dyads (36 dyads at 3 years and 36 dyads at 5 years), an initial factorial analysis revealed that parental discourse was organized on three levels of distancing: a basic level, a recontextualization level and a symbolic level. We also found that the children’s memory performances at both ages were chiefly influenced by the symbolic level, the most cognitively demanding. Lastly, the children’s rehearsal did not have any significant effect on memory performances, unlike their age, which was the primary predictor. A model featuring the various factors we studied is proposed in the discussion.  相似文献   
44.
The purpose of this study is to identify student expectations for course workload and teacher availability and to assess whether teacher nonverbal immediacy influences these student expectations. Based on a sample of 198 students at a large public university enrolled in a required general education hybrid communication course, students were willing to complete more work than the current course requires, which is comparable to other general education hybrid communication courses in the USA. Additionally, students have moderate to high expectations for teacher availability. Student perceptions of teacher nonverbal immediacy were positively correlated with students’ willingness to engage in their learning (reading, writing, speaking), teacher availability expectations, and tolerance for teacher unavailability.  相似文献   
45.
This study develops a free-entry model of competition between media firms, characterizes its equilibrium, and establishes that the industry displays a natural tendency to concentrate. A merger of any 2 firms is strictly profit increasing. Therefore, incentives to consolidate, while maintaining distinct, costly locations (i.e., production units or content), exist. This study distinguishes between post-entry and ex ante consolidation and investigates the properties of the post-consolidation equilibrium. Some firms not involved in any merger may be forced to exit. So, although media mergers may not result in shutting down any of the merging outlets, they still may indirectly affect diversity.  相似文献   
46.
We present a low cost microfluidic chip integrating 3D micro-chambers for the capture and the analysis of cells. This device has a simple design and a small footprint. It allows the implementation of standard biological protocols in a chip format with low volume consumption. The manufacturing process relies on hot-embossing of cyclo olefin copolymer, allowing the development of a low cost and robust device. A 3D design of microchannels was used to induce high flow velocity contrasts in the device and provide a selective immobilization. In narrow distribution channels, the liquid velocity induces a shear stress that overcomes adhesion forces and prevents cell immobilization or clogging. In large 3D chambers, the liquid velocity drops down below the threshold for cell attachment. The devices can be operated in a large range of input pressures and can even be handled manually using simple syringe or micropipette. Even at high flow injection rates, the 3D structures protect the captured cell from shear stress. To validate the performances of our device, we implemented immuno-fluorescence labeling and Fluorescence in Situ Hybridization (FISH) analysis on cancer cell lines and on a patient pleural effusion sample. FISH is a Food and Drug Administration approved cancer diagnostic technique that provides quantitative information about gene and chromosome aberration at the single cell level. It is usually considered as a long and fastidious test in medical diagnosis. This process can be easily implanted in our platform, and high resolution fluorescence imaging can be performed with reduced time and computer intensiveness. These results demonstrate the potential of this chip as a low cost, robust, and versatile tool adapted to complex and demanding protocols for medical diagnosis.  相似文献   
47.
Microfluidics offers unique ways of handling and manipulating microorganisms, which has particularly benefited Caenorhabditis elegans research. Optics plays a major role in these microfluidic platforms, not only as a read-out for the biological systems of interest but also as a vehicle for applying perturbations to biological systems. Here, we describe different areas of research in C. elegans developmental biology and behavior neuroscience enabled by microfluidics combined with the optical components. In particular, we highlight the diversity of optical tools and methods in use and the strategies implemented in microfluidics to make the devices compatible with optical techniques. We also offer some thoughts on future challenges in adapting advancements in optics to microfluidic platforms.  相似文献   
48.
Understanding the cognitive processes central to mathematical development is crucial to addressing systemic inequities in math achievement. We investigate the “Groupitizing” ability in 1209 third to eighth graders (mean age at first timepoint = 10.48, 586 girls, 39.16% Asian, 28.88% Hispanic/Latino, 18.51% White), a process that captures the ability to use grouping cues to access the exact value of a set. Groupitizing improves each year from late childhood to early adolescence (d = 3.29), is a central predictor of math achievement (beta weight = .30), is linked to conceptual processes in mathematics (minimum d = 0.69), and helps explain the dynamic between the ongoing development of non-symbolic number concepts, systemic educational inequities in school associated with SES, and mathematics achievement (minimum beta weight = .11) in ways that explicit symbolic measures may miss.  相似文献   
49.
ABSTRACT

This study investigated split-step timing when returning serves and whether this timing is related to neuromechanical capabilities in world-class tennis players. In Experiment 1, the split-step timing of four groups of world-class players (male and female ATP/WTA seniors, and ITF juniors) was measured on court when returning serves of the same level players. The four groups initiated the split-step at a similar time, starting around the time ball-racket contact in the serve stroke and landed when early ball-flight information was available. In Experiment 2, the neuromechanical capabilities (leg stiffness and vertical jump performance) of a group of world-class players and three groups of less-skilled tennis players were examined. The results showed an increase in leg stiffness with an increase in the level of expertise. A cross-experiment analysis in world-class male players (ATP/ITF, n = 10) revealed that the timing of initial foot movement was significantly correlated with the leg stiffness (r2 = 0.54), with later lateral step after the serve in the players who had higher stiffness. The findings support the hypothesis that world-class tennis players adapt perceptual-motor control on the basis of their neuromechanical capabilities and maximise the time before initiating their interceptive action to rely on more reliable information.  相似文献   
50.
In tennis, a high ball velocity and a fast run toward the net are key features to successful performance of "serve-and-volley" players. For the serve, tennis players can use two techniques: the foot-up (FU) or foot-back (FB) technique. The aim of this study was to determine if the running time toward the net after the serve and the ball velocity (V(ball)) vary between these two techniques. Moreover we analysed the angular momentum values of the trunk and of the arm holding the racquet. Fifteen expert tennis players performed six successful serve-and-volleys with both techniques. Running time to the net is significantly lower for FB, whereas V(ball) is significantly higher for FU. Trunk and arm angular momentums about the transverse axis are significantly higher with FU before ball impact. A significant correlation (r = 0.81, P < 0.001) exists between changes in the maximal trunk angular momentum and in running time to the net between the two serve techniques. A significant correlation (r = 0.84, P < 0.001) also exists between changes in the maximal trunk angular momentum and in V(ball) between the two serve techniques. According to these results, FB is the best technique for moving as quickly as possible to the net because of a lower trunk angular momentum.  相似文献   
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