96,443 research outputs found

    Indirect effects between deer, mice, and the gypsy moth in a forest community

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    White-tailed deer are ecosystem engineers that dramatically alter forest understory vegetation. Consequently, deer can impact many species in a forest through both direct and indirect effects. One species that deer may indirectly affect is the gypsy moth, whose pupae are preyed upon by the white-footed mouse. Through alterations to understory habitat of mice, deer may reduce mouse predation on gypsy moth pupae. In this study, I tested for indirect effects of deer on the gypsy moth by comparing mouse abundance, vegetation properties, and predation on pupae inside, and outside, of long-term deer exclosures. Overall, I did not find evidence for indirect effects of deer on the gypsy moth. There was little effect of the exclosures on mouse abundance, predation rates, and habitat measures. High mouse abundances, which likely resulted from a large acorn mast the previous year, may be obscuring indirect effects that would be detected at lower mouse abundances

    New Experimental Limits on Macroscopic Forces Below 100 Microns

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    Results of an experimental search for new macroscopic forces with Yukawa range between 5 and 500 microns are presented. The experiment uses 1 kHz mechanical oscillators as test masses with a stiff conducting shield between them to suppress backgrounds. No signal is observed above the instrumental thermal noise after 22 hours of integration time. These results provide the strongest limits to date between 10 and 100 microns, improve on previous limits by as much as three orders of magnitude, and rule out half of the remaining parameter space for predictions of string-inspired models with low-energy supersymmetry breaking. New forces of four times gravitational strength or greater are excluded at the 95% confidence level for interaction ranges between 200 and 500 microns.Comment: 25 Pages, 7 Figures: Minor Correction

    A longitudinal study of grapheme-color synesthesia in childhood:6/7 years to 10/11 years

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    Grapheme-colour synaesthesia is a condition characterised by enduring and consistent associations between letter/digits and colours. This study is the continuation of longitudinal research begun by Simner, Harrold, Creed, Monro and Foulkes (2009) which aimed to explore the development of this condition in real time within a childhood population. In that earlier study we randomly sampled over 600 children and tested them aged 6/7 years and 7/8 years. We identified the child synaesthetes within that cohort and measured their development over 1 year, in comparison to a group of nonsynaesthetic children with both average and superior memories. We were able to show the beginnings of a developmental progression in which synaesthetic associations (e.g. A = red) mature over time from relatively chaotic pairings into a system of fixed consistent associations. In the current study we return to this same population three years later when participants are now 10/11 years. We used the same paired-association memory task to determine the synaesthetic status of our participants and to also establish synaesthetes’ inventories of grapheme-colour associations. We compared their inventories to those from age 6/7 year and 7/8 years to examine how synaesthesia matures over time. Together with earlier findings, our study shows that grapheme-colour synaesthesia emerges with a protracted lineal trajectory, with 34% of letters/digits fixed at age 6/7 years, 48% fixed at 7/8 years and 71% fixed at 10/11 years. We also show several cases where synaesthesia is not developing in the same time-frame as peers, either because it has died out at an older age, or because it was slower to develop than other cases. Our study paints the first picture of the emergence of synaesthesia in real-time over four years within a randomly sampled population of child synaesthetes

    CAHRS hrSpectrum (November-December 2008)

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    HRSpec2008_12.pdf: 478 downloads, before Oct. 1, 2020

    Focused Proofreading: Efficiently Extracting Connectomes from Segmented EM Images

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    Identifying complex neural circuitry from electron microscopic (EM) images may help unlock the mysteries of the brain. However, identifying this circuitry requires time-consuming, manual tracing (proofreading) due to the size and intricacy of these image datasets, thus limiting state-of-the-art analysis to very small brain regions. Potential avenues to improve scalability include automatic image segmentation and crowd sourcing, but current efforts have had limited success. In this paper, we propose a new strategy, focused proofreading, that works with automatic segmentation and aims to limit proofreading to the regions of a dataset that are most impactful to the resulting circuit. We then introduce a novel workflow, which exploits biological information such as synapses, and apply it to a large dataset in the fly optic lobe. With our techniques, we achieve significant tracing speedups of 3-5x without sacrificing the quality of the resulting circuit. Furthermore, our methodology makes the task of proofreading much more accessible and hence potentially enhances the effectiveness of crowd sourcing

    Conducting Peer Assists

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    {Excerpt} The experience that an organization has gained is its most important asset. Exit interviews are a way of capturing knowledge from leavers, but can only be relied upon once. Peer assists capture knowledge before employees leave, and in such ways that can repeatedly apply and strengthen good practiceas well as consistency across an organization. The formal use of peer assists as a management tool was pioneered by British Petroleum to help staff learn from the experiencesof others before they embark on an activity or project. Put simply, a peer assist is the process whereby a team working on an activity or project calls a meeting or workshop to seek knowledge and insights from a good mix of people in other teams. From the onset, the distinction between a peer assist and a peer review should be made explicit: without it participants will fall into the familiar patterns of peer reviews and little knowledge will be transferred

    Educational Research Abstracts

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    Editors\u27 Note: As noted in previous issues of the Journal of Mathematics and Science: Collaborative Explorations, the purpose of this Educational Research Abstract section is to present current research on issues relevant to math and science teaching at both the K-12 and college levels. Because educational research studies are published in so many different academic journals and presented as so many different professional conferences, it is a rare public school teacher or college professor who is familiar with the range of recent reposts on a particular instructional technique or curricular advancement. Indeed, the uniqueness of various pedagogical strategies has been tacitly acknowledged by the creation of individual journals and professional organizations dedicated to teaching in a specific discipline. Yet, many of the insights gained in teaching certain physics concepts, biological principles, or computer science algorithms can have generalizability and value for those teaching in other fields or with different types of students. In this review, the focus is on cutting edge research. Abstracts are presented according to a question examined at a recent national educational research conference. Hopefully, such a format will trigger your interest in how you might incorporate new educational findings in your own teaching situation. The abstracts presented here are not intended to be exhaustive, but rather a representative sampling of recent research investigations. Please feel free to suggest future teaching or learning themes to be examined. Please send your comments and ideas via e-mail to [email protected] or by regular mail to The College of William and Mary, P. O. Box 8795, Williamsburg, VA 23185-8795

    Session Types in Abelian Logic

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    There was a PhD student who says "I found a pair of wooden shoes. I put a coin in the left and a key in the right. Next morning, I found those objects in the opposite shoes." We do not claim existence of such shoes, but propose a similar programming abstraction in the context of typed lambda calculi. The result, which we call the Amida calculus, extends Abramsky's linear lambda calculus LF and characterizes Abelian logic.Comment: In Proceedings PLACES 2013, arXiv:1312.221
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