1,835 research outputs found

    Using a Delphi technique to seek consensus regarding definitions, descriptions and classification of terms related to implicit and explicit forms of motor learning.

    Get PDF
    Published onlineJournal ArticleResearch Support, Non-U.S. Gov'tBACKGROUND: Motor learning is central to domains such as sports and rehabilitation; however, often terminologies are insufficiently uniform to allow effective sharing of experience or translation of knowledge. A study using a Delphi technique was conducted to ascertain level of agreement between experts from different motor learning domains (i.e., therapists, coaches, researchers) with respect to definitions and descriptions of a fundamental conceptual distinction within motor learning, namely implicit and explicit motor learning. METHODS: A Delphi technique was embedded in multiple rounds of a survey designed to collect and aggregate informed opinions of 49 international respondents with expertise related to motor learning. The survey was administered via an online survey program and accompanied by feedback after each round. Consensus was considered to be reached if ≥70% of the experts agreed on a topic. RESULTS: Consensus was reached with respect to definitions of implicit and explicit motor learning, and seven common primary intervention strategies were identified in the context of implicit and explicit motor learning. Consensus was not reached with respect to whether the strategies promote implicit or explicit forms of learning. DISCUSSION: The definitions and descriptions agreed upon may aid translation and transfer of knowledge between domains in the field of motor learning. Empirical and clinical research is required to confirm the accuracy of the definitions and to explore the feasibility of the strategies that were identified in research, everyday practice and education.Stichting Alliantie Innovatie (Innovation Alliance Foundation)RAAK-internationa

    Multidisciplinary Views on Applying Explicit and Implicit Motor Learning in Practice: An International Survey.

    Get PDF
    Published onlineJournal ArticleResearch Support, Non-U.S. Gov'tBACKGROUND: A variety of options and techniques for causing implicit and explicit motor learning have been described in the literature. The aim of the current paper was to provide clearer guidance for practitioners on how to apply motor learning in practice by exploring experts' opinions and experiences, using the distinction between implicit and explicit motor learning as a conceptual departure point. METHODS: A survey was designed to collect and aggregate informed opinions and experiences from 40 international respondents who had demonstrable expertise related to motor learning in practice and/or research. The survey was administered through an online survey tool and addressed potential options and learning strategies for applying implicit and explicit motor learning. Responses were analysed in terms of consensus (≥ 70%) and trends (≥ 50%). A summary figure was developed to illustrate a taxonomy of the different learning strategies and options indicated by the experts in the survey. RESULTS: Answers of experts were widely distributed. No consensus was found regarding the application of implicit and explicit motor learning. Some trends were identified: Explicit motor learning can be promoted by using instructions and various types of feedback, but when promoting implicit motor learning, instructions and feedback should be restricted. Further, for implicit motor learning, an external focus of attention should be considered, as well as practicing the entire skill. Experts agreed on three factors that influence motor learning choices: the learner's abilities, the type of task, and the stage of motor learning (94.5%; n = 34/36). Most experts agreed with the summary figure (64.7%; n = 22/34). CONCLUSION: The results provide an overview of possible ways to cause implicit or explicit motor learning, signposting examples from practice and factors that influence day-to-day motor learning decisions.Stichting Innovatie Alliantie (Innovation Alliance Foundation)RAAK-internationa

    Hexamerization-enhanced CD20 antibody mediates complement-dependent cytotoxicity in serum genetically deficient in C9

    Get PDF
    We examined complement-dependent cytotoxicity (CDC) by hexamer formation-enhanced CD20 mAb Hx-7D8 of patient-derived chronic lymphocytic leukemia (CLL) cells that are relatively resistant to CDC. CDC was analyzed in normal human serum (NHS) and serum from an individual genetically deficient for C9. Hx-7D8 was able to kill up to 80% of CLL cells in complete absence of C9. We conclude that the narrow C5b-8 pores formed without C9 are sufficient for CDC due to efficient antibody-mediated hexamer formation. In the absence of C9, we observed transient intracellular increases of Ca2 + during CDC (as assessed with FLUO-4) that were extended in time. This suggests that small C5b-8 pores allow Ca2 + to enter the cell, while dissipation of the fluorescent signal accompanying cell disintegration is delayed. The Ca2 + signal is retained concomitantly with TOPRO-3 (viability dye) staining, thereby confirming that Ca2 + influx represents the most proximate mediator of cell death by CDC

    Opening of endothelial cell–cell contacts due to sonoporation

    Get PDF
    Ultrasound insonification of microbubbles can locally increase vascular permeability to enhance drug delivery. To control and optimize the therapeutic potential, we need to better understand the underlying biological mechanisms of the drug delivery pathways. The aim of this in vitro study was to elucidate the microbubble-endothelial cell interaction using the Brandaris 128 ultra-high-speed camera (up to 25 Mfps) coupled to a custom-built Nikon confocal microscope, to visualize both microbubble oscillation and the cellular response. Sonoporation and opening of cell-cell contacts by single αVβ3-targeted microbubbles (n = 152) was monitored up to 4 min after ultrasound insonification (2 MHz, 100–400 kPa, 10 cycles). Sonoporation occurred when microbubble excursion amplitudes exceeded 0.7 μm. Quantification of the influx of the fluorescent model drug propidium iodide upon sonoporation showed that the size of the created pore increased for larger microbubble excursion amplitudes. Microbubble-mediated opening of cell-cell contacts occurred as a cellular response upon sonoporation and did not correlate with the microbubble excursion amplitude itself. The initial integrity of the cell-cell contacts affected the susceptibly to drug delivery, since cell-cell contacts opened more often when cells were only partially attached to their neighbors (48%) than when fully attached (14%). The drug delivery outcomes were independent of nonlinear microbubble behavior, microbubble location, and cell size. In conclusion, by studying the microbubble–cell interaction at nanosecond and nanometer resolution the relationship between drug delivery pathways and their underlying mechanisms was further unraveled. These novel insights will aid the development of safe and efficient microbubble-mediated drug delivery
    • …
    corecore