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971.
To reduce sensory uncertainty, humans combine cues from multiple senses. However, in everyday life, many co‐occurring cues are irrelevant to the task at hand. How do humans know which cues to ignore? And does this ability change with development? This study shows the ability to ignore cross‐modal irrelevant information develops late in childhood. Participants performed a sound discrimination task, with or without an irrelevant visual flash, presented synchronously in front of them. Adults ignored the irrelevant visual information, while 7‐ to 10‐year‐olds' responses were biased toward the flash location. The findings show that acquiring mature cue combination mechanisms is a multifaceted process that includes learning to ignore irrelevant cues, as well as to optimally combine relevant cues.  相似文献   
972.
Implantable drug delivery devices are becoming attractive due to their abilities of targeted and controlled dose release. Currently, two important issues are functional lifetime and non-controlled drug diffusion. In this work, we present a drug delivery device combining an electrolytic pump and a thermo-responsive valve, which are both remotely controlled by an electromagnetic field (40.5 mT and 450 kHz). Our proposed device exhibits a novel operation mechanism for long-term therapeutic treatments using a solid drug in reservoir approach. Our device also prevents undesired drug liquid diffusions. When the electromagnetic field is on, the electrolysis-induced bubble drives the drug liquid towards the Poly (N-Isopropylacrylamide) (PNIPAM) valve that consists of PNIPAM and iron micro-particles. The heat generated by the iron micro-particles causes the PNIPAM to shrink, resulting in an open valve. When the electromagnetic field is turned off, the PNIPAM starts to swell. In the meantime, the bubbles are catalytically recombined into water, reducing the pressure inside the pumping chamber, which leads to the refilling of the fresh liquid from outside the device. A catalytic reformer is included, allowing more liquid refilling during the limited valve''s closing time. The amount of body liquid that refills the drug reservoir can further dissolve the solid drug, forming a reproducible drug solution for the next dose. By repeatedly turning on and off the electromagnetic field, the drug dose can be cyclically released, and the exit port of the device is effectively controlled.  相似文献   
973.
This study investigated whether neuromuscular fatigue affects the neuromuscular control of an athlete within a sports context setting and whether these effects were more pronounced in the females. Lower limb joint kinetics of 6 male and 6 female inter-varsity soccer players performing side-stepping tasks in non-fatigue versus fatigue and anticipated versus unanticipated conditions were quantified using 10 Motion Analysis Corporation cameras and a Kistler? force platform. The Yo-Yo intermittent recovery Level 1 fatigue protocol was employed. Stance foot initial contact and peak forces, and peak joint knee moments of the lower limb were submitted to a 3-way mixed-model repeated measure ANOVA. The results suggested that males tend to elicit significantly higher knee joint loadings when fatigued. In addition, males elicited significantly higher peak proximal tibia anterior/posterior shear force, vertical ground reaction force at initial contact and peak internal rotational moments than females. These findings suggested that males were at greater overall injury risk than females, especially in the sagittal plane. Neuromuscular control-based training programmes/interventions that are designed to reduce the risk of the non-contact ACL injury need to be customised for the different genders.  相似文献   
974.
Ian Syson 《国际体育史杂志》2015,32(13):1567-1577
Immediately after WW1, soccer had acquired a small but secure place in Melbourne sports culture. Soccer's commitment to the war effort potentially gave its adherents entry to the foundations of a new national mythology. Increasing migrant numbers in the 1920s grew the number of soccer's participants and supporters. Perhaps counterintuitively, this growth was accompanied by a growing distance between the game and notions of Australianness. This paper traces the cooling of soccer's welcome in Melbourne between 1920 and 1934 to the point where the game was cast to the margins of Australian identity.  相似文献   
975.
In 2010, the Association for the Advancement of Sustainability in Higher Education released, “Sustainability curriculum in higher education: A call to action,” encouraging infusion of sustainability topics into universities' teaching and research. Since then, academic programs and research related to social, economic, and environmental sustainability have enriched university curricula. An exploratory study was conducted to determine the position and engagements of academic libraries and information science schools in their contributions to scholarly sustainability activities and curricular initiatives. This article presents the results of the study which reveals a number of engagements by library professionals in the areas of sustainability, such as increasing open access to research, building sustainability-related collections and research guides, and incorporating sustainability content into information literacy. While academic libraries and information science schools are engaged in a broad spectrum of initiatives that support their institutions' sustainability research and curricular functions, this study indicates that such activities require a more targeted approach.  相似文献   
976.
Understanding theory–practice relationships in pre-service teacher education is an enduring concern for many teacher educators. Drawing on data from an investigation into the theory–practice nexus in an outdoor education teacher education programme, this article examines pedagogical approaches to exploring theory and practice with pre-service teachers. The investigation, a qualitative case study, examined the views of the programme’s teacher educators (authors) using an analytical lens informed by two similar theoretical models.

The article focuses on elements that were found to be central to pedagogical approaches within the programme: self-awareness, experience, reflexivity, and a “community of learners.” While the approaches represent a departure from “theory application” and “theory–practice integration” approaches, and a move towards praxis development, the study highlighted challenges and issues including the need for teacher educators to scrutinise theory–practice relationships in their own teaching and discourse. Implications and possibilities for future practice are considered.  相似文献   

977.
In 2012, an academic health sciences library serving a large research university and medical center introduced synchronous online training for a diverse group of users, including clinicians, researchers, faculty, and distance students. Participants in these “Express Training” classes completed two surveys to assess their experiences. Survey results indicated classes were well received but revealed some areas for improvement. Included are issues that should be considered when implementing online library instruction to meet the diverse needs of academic health sciences library users. Given the popularity of online training among on-campus and distance users, it will be continued and expanded.  相似文献   
978.
Providing a rich context has become a sine qua non of principled teaching of applied statistical thinking. With increasing opportunities to access secondary data, there should be increasing opportunity to work with rich context. We review the contextual information provided in 41 data sets suitable for introductory tertiary statistics teaching, available in the R “datasets” package, and investigate the source information for four data sets. We find failure to describe and retain important contextual information, including aspects that raise questions about the credibility of the data for statistical inference. The sanitization of data reduces the opportunities for learning meaningful lessons in statistical thinking and the real-world application of statistics. We advocate for teachers and users of such data to be curious about the provenance and context, and for the curators and distributors to examine, where possible, the primary sources, to accurately preserve the context and optimize pedagogical opportunities.  相似文献   
979.
Both general and domain-specific search engines have adopted query suggestion techniques to help users formulate effective queries. In the specific domain of literature search (e.g., finding academic papers), the initial queries are usually based on a draft paper or abstract, rather than short lists of keywords. In this paper, we investigate phrasal-concept query suggestions for literature search. These suggestions explicitly specify important phrasal concepts related to an initial detailed query. The merits of phrasal-concept query suggestions for this domain are their readability and retrieval effectiveness: (1) phrasal concepts are natural for academic authors because of their frequent use of terminology and subject-specific phrases and (2) academic papers describe their key ideas via these subject-specific phrases, and thus phrasal concepts can be used effectively to find those papers. We propose a novel phrasal-concept query suggestion technique that generates queries by identifying key phrasal-concepts from pseudo-labeled documents and combines them with related phrases. Our proposed technique is evaluated in terms of both user preference and retrieval effectiveness. We conduct user experiments to verify a preference for our approach, in comparison to baseline query suggestion methods, and demonstrate the effectiveness of the technique with retrieval experiments.  相似文献   
980.
A spiral inertial filtration (SIFT) device that is capable of high-throughput (1 ml/min), high-purity particle separation while concentrating recovered target particles by more than an order of magnitude is reported. This device is able to remove large fractions of sample fluid from a microchannel without disruption of concentrated particle streams by taking advantage of particle focusing in inertial spiral microfluidics, which is achieved by balancing inertial lift forces and Dean drag forces. To enable the calculation of channel geometries in the SIFT microsystem for specific concentration factors, an equivalent circuit model was developed and experimentally validated. Large particle concentration factors were then achieved by maintaining either the average fluid velocity or the Dean number throughout the entire length of the channel during the incremental removal of sample fluid. The SIFT device was able to separate MCF7 cells spiked into whole blood from the non-target white blood cells (WBC) with a recovery of nearly 100% while removing 93% of the sample volume, which resulted in a concentration enhancement of the MCF7 cancer cells by a factor of 14.  相似文献   
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