174 research outputs found

    Suzaku Detection of Diffuse Hard X-Ray Emission outside Vela X

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    Vela X is a large, 3x2 degrees, radio-emitting pulsar wind nebula (PWN) powered by the Vela pulsar in the Vela supernova remnant. Using four Suzaku/XIS observations pointed just outside Vela X, we find hard X-ray emission extending throughout the fields of view. The hard X-ray spectra are well represented by a power-law. The photon index is measured to be constant at Gamma~2.4, similar to that of the southern outer part of Vela X. The power-law flux decreases with increasing distance from the pulsar. These properties lead us to propose that the hard X-ray emission is associated with the Vela PWN. The larger X-ray extension found in this work strongly suggests that distinct populations relativistic electrons form the X-ray PWN and Vela X, as was recently inferred from multiwavelength spectral modeling of Vela X.Comment: 18 pages, 7 figures, accepted for publication in PASJ (Suzaku Special Issue

    Assessing the influence of dopamine and mindfulness on the formation of routines in visual search

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    Given experience in cluttered but stable visual environments, our eye‐movements form stereotyped routines that sample task‐relevant locations, while not mixing‐up routines between similar task‐settings. Both dopamine signaling and mindfulness have been posited as factors that influence the formation of such routines, yet quantification of their impact remains to be tested in healthy humans. Over two sessions, participants searched through grids of doors to find hidden targets, using a gaze‐contingent display. Within each session, door scenes appeared in either one of two colors, with each color signaling a differing set of likely target locations. We derived measures for how well target locations were learned (target‐accuracy), how routine were sets of eye‐movements (stereotypy), and the extent of interference between the two scenes (setting‐accuracy). Participants completed two sessions, where they were administered either levodopa (dopamine precursor) or placebo (vitamin C), under double‐blind counterbalanced conditions. Dopamine and trait mindfulness (assessed by questionnaire) interacted to influence both target‐accuracy and stereotypy. Increasing dopamine improved accuracy and reduced stereotypy for high mindfulness scorers, but induced the opposite pattern for low mindfulness scorers. Dopamine also disrupted setting‐accuracy invariant to mindfulness. Our findings show that mindfulness modulates the impact of dopamine on the target‐accuracy and stereotypy of eye‐movement routines, whereas increasing dopamine promotes interference between task‐settings, regardless of mindfulness. These findings provide a link between non‐human and human models regarding the influence of dopamine on the formation of task‐relevant eye‐movement routines and provide novel insights into behavior‐trait factors that modulate the use of experience when building adaptive repertoires

    Amyloid pathology fingerprint differentiates post-traumatic stress disorder and traumatic brain injury

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    INTRODUCTION: Traumatic brain injury (TBI) and post-traumatic stress disorder (PTSD) are risk factors for early onset of Alzheimer's disease (AD) and may accelerate the progression rate of AD pathology. As amyloid-beta (Aβ) plaques are a hallmark of AD pathology, we hypothesized that TBI and PTSD might increase Aβ accumulation in the brain. METHODS: We examined PET and neuropsychological data from Vietnam War veterans compiled by the US Department of Defense Alzheimer's Disease Neuroimaging Initiative, to examine the spatial distribution of Aβ in male veterans' who had experienced a TBI and/or developed PTSD. Subjects were classified into controls, TBI only, PTSD only, and TBI with PTSD (TBI_PTSD) groups and data were analyzed using both voxel-based and ROI-based approaches. RESULTS: Compared to controls, all three clinical groups showed a pattern of mainly increased referenced standard uptake values (SUVR) for the amyloid tracer [18F]-AV45 PET, with rank order PTSD > TBI_PTSD > TBI > Control, and same rank order was seen in the deficits of cognitive functions. SUVR increase was observed in widespread cortical regions of the PTSD group; in white matter of the TBI_PTSD group; and cerebellum and precuneus area of the TBI group, in contrast with controls. The [18F]-AV45 SUVR correlated negatively with cerebrospinal fluid (CSF) amyloid levels and positively with the CSF tau concentrations. CONCLUSION: These results suggest that both TBI and PTSD are substantial risk factors for cognition decline and increased Aβ deposition resembling that in AD. In addition, both PTSD and TBI_PTSD have a different pathways of Aβ accumulation

    Living with Family Is Directly Associated with Regular Dental Checkup and Indirectly Associated with Gingival Status among Japanese University Students: A 3-Year Cohort Study

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    Although some studies showed that lifestyle was associated with oral health behavior, few studies investigated the association between household type and oral health behavior. The aim of this prospective cohort study was to investigate the association between household type, oral health behavior, and periodontal status among Japanese university students. Data were obtained from 377 students who received oral examinations and self-questionnaires in 2016 and 2019. We assessed periodontal status using the percentage of bleeding on probing (%BOP), probing pocket depth, oral hygiene status, oral health behaviors, and related factors. We used structural equation modeling to determine the association between household type, oral health behaviors, gingivitis, and periodontitis. At follow-up, 252 students did not live with their families. The mean +/- standard deviation of %BOP was 35.5 +/- 24.7 at baseline and 32.1 +/- 25.3 at follow-up. In the final model, students living with their families were significantly more likely to receive regular dental checkup than those living alone. Regular checkup affected the decrease in calculus. The decrease in calculus affected the decrease in %BOP over 3 years. Living with family was directly associated with regular dental checkups and indirectly contributed to gingival status among Japanese university students

    助産診断技術論演習におけるシミュレーション教育方法の実践報告

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     分娩期における助産診断・技術の習得を目指したシミュレーション教育の方法として,模擬患者,シミュレーター,オリジナル教材,映像の活用を組み合わせた助産診断技術論演習の実際について報告する.本演習授業である30コマのうち,分娩期の助産診断・技術に関する演習を12コマ実施した.4コマで1事例の演習を行い,3事例の設定をした.単元の流れは,①事例を提示,②初期診断を行い,ベッドサイドでの情報収集項目を整理,③模擬産婦から情報収集,④アセスメントにより,分娩進行の助産診断および助産ケアの計画立案,ならびにベッドサイドで得る情報項目の確認,⑤模擬産婦へ助産ケアの実施,ならびに情報収集を行う.これら,一連の助産過程を実施し,その場面を撮影して学習教材の一部とした.また,シミュレーターを組み合わせて活用し,作成したオリジナル教材を用いた.その結果,教員からみた学生は,分娩進行やその過程についてイメージを描くことができ,正常経過の分娩進行に対する知識が得られ,助産ケアが実施できたと思われた.また,本演習のシミュレーション教育により,コミュニケーション能力と事例に関する知識,技術の向上が示唆された
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