86 research outputs found

    Deflection angle of light in an Ellis wormhole geometry

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    We reexamine the light deflection by an Ellis wormhole. The bending angle as a function of the ratio between the impact parameter and the throat radius of the wormhole is obtained in terms of a complete elliptic integral of the first kind. This result immediately yields asymptotic expressions in the weak field approximation. It is shown that an expression for the deflection angle derived (and used) in recent papers is valid at the leading order but it breaks down at the next order because of the nontrivial spacetime topology.Comment: 3 pages, accepted by PR

    Relevance between Alzheimer’s disease patients and normal subjects using go/no-go tasks and Alzheimer assessment scores

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    It is a well-known fact that Alzheimer increases with aging. Early detection of Alzheimer has emerged as an important, because it can prevent of further deterioration of the disease. However, early detection is not always easy because of the lack of good methods to identify the early stage of Alzheimer. The screening tests of Alzheimer used around the world. These tests are relatively time-consuming, difficult and distressing for Alzheimer patients. We consider whether go/no-go task can become the screening test of the Alzheimer patient in future. This study compared results of the Mini Mental State Examination (MMSE) and the go/no-go task for between Alzheimer disease patients and normal subjects. The average reaction time and number of total error of go/no-go task that Alzheimer patients were significantly higher than among the normal subjects. About correlation with MMSE and the go/no-go task, 6 items of MMSE had correlations of 4 or more test results concerning response time, forgets and mistakes of go/no-go tasks. These characteristics suggest that there is a possibility that go/no-go tasks could be applied as a measuring method when screening for early signs of Alzheimer.ArticleJournal of Child and Adolescent Behaviour.2(4):162(2014)journal articl
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