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991.
M. Skolimowski M. Weiss Nielsen F. Abeille P. Skafte-Pedersen D. Sabourin A. Fercher D. Papkovsky S. Molin R. Taboryski C. Sternberg M. Dufva O. Geschke J. Emnéus 《Biomicrofluidics》2012,6(3)
A modular microfluidic airways model system that can simulate the changes in oxygen tension in different compartments of the cystic fibrosis (CF) airways was designed, developed, and tested. The fully reconfigurable system composed of modules with different functionalities: multichannel peristaltic pumps, bubble traps, gas exchange chip, and cell culture chambers. We have successfully applied this system for studying the antibiotic therapy of Pseudomonas aeruginosa, the bacteria mainly responsible for morbidity and mortality in cystic fibrosis, in different oxygen environments. Furthermore, we have mimicked the bacterial reinoculation of the aerobic compartments (lower respiratory tract) from the anaerobic compartments (cystic fibrosis sinuses) following an antibiotic treatment. This effect is hypothesised as the one on the main reasons for recurrent lung infections in cystic fibrosis patients. 相似文献
992.
A low digit ratio (2D:4D) and low 2D:4D in the right compared with the left hand (right-left 2D:4D) are thought to be determined by high in utero concentrations of testosterone, and are related to "masculine" traits such as aggression and performance in sports like running and rugby. Low right-left 2D:4D is also related to sensitivity to testosterone as measured by the number of cytosine-adenine-guanine triplet repeats in exon 1 of the androgen receptor gene. Here we show that low right-left 2D:4D is associated with high maximal oxygen uptake (VO2(max)), high velocity at VO2(max), and high maximum lactate concentration in a sample of teenage boys. We suggest that low right-left 2D:4D is linked to performance in some sports because it is a proxy of high sensitivity to prenatal and maybe also circulating testosterone and high VO2(max). 相似文献
993.
Characterising the impact performance of field hockey sticks 总被引:1,自引:1,他引:0
Published research on field hockey equipment is scarce. The aim of this research was to investigate methods for characterising the impact performance of field hockey sticks. Three sticks were used with fundamental frequencies in the range 74?C154?Hz. Striking an initially still ball with a stick was identified as the preferred method for characterising performance. Impacts were simulated at mean velocities of 19?m/s at toe and 16?m/s at the shaft. The mean apparent coefficient of restitution and standard deviation were ?0.32?±?0.05 at the toe and ?0.18?±?0.02 at the shaft. The foundation work presented here provides the foundations for developing a methodology for characterising the impact performance of field hockey sticks. 相似文献
994.
Relations between physiological and cognitive regulatory systems: infant sleep regulation and subsequent executive functioning 总被引:1,自引:0,他引:1
The aim of this report was to investigate the prospective links between infant sleep regulation and subsequent executive functioning (EF). The authors assessed sleep regulation through a parent sleep diary when children were 12 and 18 months old (N = 60). Child EF was assessed at 18 and 26 months of age. Higher proportions of total sleep occurring at night time, at both 12 and 18 months, were related to better performance on executive tasks, especially those involving a strong impulse control component. Most relations held above family socioeconomic status, prior mental development and concurrent verbal ability. These findings add to previous results with school-age children in suggesting that sleep favors the development of higher order cognitive functions requiring prefrontal cortex involvement. 相似文献
995.
Cyril Rebetez Mireille Bétrancourt Mirweis Sangin Pierre Dillenbourg 《Instructional Science》2010,38(5):471-485
Animated graphics are extensively used in multimedia instructions explaining how natural or artificial dynamic systems work.
As animation directly depicts spatial changes over time, it is legitimate to believe that animated graphics will improve comprehension
over static graphics. However, the research failed to find clear evidence in favour of animation. Animation may also be used
to promote interactions in computer-supported collaborative learning. In this setting as well, the empirical studies have
not confirmed the benefits that one could intuitively expect from the use of animation. One explanation is that multimedia,
including animated graphics, challenges human processing capacities, and in particular imposes a substantial working memory
load. We designed an experimental study involving three between-subjects factors: the type of multimedia instruction (with
static or animated graphics), the presence of snapshots of critical steps of the system (with or without snapshots) and the
learning setting (individual or collaborative). The findings indicate that animation was overall beneficial to retention,
while for transfer, only learners studying collaboratively benefited from animated over static graphics. Contrary to our expectations,
the snapshots were marginally beneficial to learners studying individually and significantly detrimental to learners studying
in dyads. The results are discussed within the multimedia comprehension framework in order to propose the conditions under
which animation can benefit to learning. 相似文献
996.
Gaïd Le Maner-Idrissi Virginie Dardier Cécile Pajon Géraldine Tan-Bescond Kristell David Michel Deleau Benoit Godey 《European Journal of Psychology of Education - EJPE》2010,25(3):265-279
Previous studies of preverbal development have highlighted the recurrent difficulties experienced by deaf children in acquiring
knowledge of the social rules and social skills pertaining to discourse. We expected cochlear implants in children with bilateral
profound deafness to improve their use of verbal language, so that their communication skill profile resembled that of younger,
hearing children. Using conversation samples taken from videos recorded every 6 months over a 2-year period, we monitored
the development of communication skills in a group of 18 prelingually profoundly deaf children (mean implantation age, 3 years
and 5 months). Results corroborated our hypothesis that the overall communication performances of children with cochlear implants
improve, both quantitatively and qualitatively, as early as the first year post-implantation. 相似文献
997.
998.
999.
Anne-Marie Adams Fiona Simmons Catherine Willis Ralph Pawling 《Journal of Research in Reading》2010,33(1):54-76
In order to communicate understanding, students are often required to produce texts which present an explicit, coherent argument. This study examined the extent to which individual differences in undergraduates' topic knowledge and working memory skills were related to their ability to revise texts to better fulfil these goals. Forty-seven students revised texts containing three types of error: language, structure and argument. Topic knowledge was indexed by multiple choice test performance. Verbal short-term and working memory were measured using forward and backward digit recall and reading span. Rates of identification, diagnosis and correction of errors were generally poor. Contrary to expectations neither topic knowledge nor verbal working memory was associated with text revision although significant associations were identified with verbal short-term memory. When revising texts students may focus on the surface features of the text rather than addressing issues of structure and argument. Possible accounts of this tendency are considered. 相似文献
1000.
Clémentine Beauvais 《Children‘s Literature in Education》2010,41(3):251-259
This article analyses the symbolic meaning of the Moon in two bande dessinée books from the Tintin series, Hergé’s Destination Moon (Objectif Lune, 1953) and its sequel Explorers on the Moon (On a Marché sur la Lune, 1954). It argues that these two volumes stand out in the series for their graphic, narrative and philosophical emphasis on both
intellectual achievement and physical death. The Moon, as a goal of modern science and a traditional artistic symbol, is made
to celebrate the human mind. But Hergé also makes it a dangerous no man’s land, where human beings are made to understand
the limitations of their physical abilities. The Moon emphasises the distortion between human dreams of grandeur and the concrete
impossibility of their realisation, and the threats they pose to corporeality. As a result, the article suggests that the
Moon trip can be seen as a modern re-enactment of the mythological journey to Hell, as the works of the human mind are constantly
thwarted by the risk of physical death. 相似文献