5 research outputs found

    Nonreciprocal coherent coupling of nanomagnets by exchange spin waves

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    Nanomagnets are widely used to store information in non-volatile spintronic devices. Spin waves can transfer information with low-power consumption as their propagations are independent of charge transport. However, to dynamically couple two distant nanomagnets via spin waves remains a major challenge for magnonics. Here we experimentally demonstrate coherent coupling of two distant Co nanowires by fast propagating spin waves in an yttrium iron garnet thin film with sub-50 nm wavelengths. Magnons in two nanomagnets are unidirectionally phase-locked with phase shifts controlled by magnon spin torque and spin-wave propagation. The coupled system is finally formulated by an analytical theory in terms of an effective non-Hermitian Hamiltonian. Our results are attractive for analog neuromorphic computing that requires unidirectional information transmission. [Figure not available: see fulltext.]Accepted Author ManuscriptQN/Bauer Grou

    Risk Factors and Neuropsychological Assessments of Subjective Cognitive Decline (plus) in Chinese Memory Clinic

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    Background: Since subjective cognitive decline (SCD) was standardized in 2014, many studies have investigated its features. However, the risk of SCD (plus) progressing to AD is much higher, and yet there have been few studies reporting the risk factors and neuropsychological assessment characteristics of SCD (plus). Objective: To characterize SCD (plus) by comparing it with normal control (NC), amnesic mild cognitive impairment (aMCI), and Alzheimer Disease (AD) regarding their demographics, lifestyle, family history of dementia, multimorbidity and the neuropsychological assessments. Methods: A total of 135 participants were recruited, including 23 NC, 30 SCD (plus), 45 aMCI and 37 AD. Descriptive statistics were provided. A logistic regression model was used to analyze the affecting factors of SCD (plus), and finally the Receiver Operating Characteristic (ROC) analysis was applied to distinguish between SCD (plus) and NC. Results: (1) SCD (plus) group was younger than both the aMCI group and AD group. It consisted of more participants with mental work and higher body mass index (BMI) than the AD group. (2) Scores of Auditory Verbal Learning Test - Immediate recall (AVLT-IR) and AVLT-Long delayed recall (AVLT-LR) decreased in the following order: NC→SCD (plus)→aMCI→AD. (3) The Area Under Curve (AUC) for discriminating SCD (plus) and NC group was from 0.673 to 0.838. Conclusion: Aging is an important risk factor of both NC progressing to SCD (plus), and SCD (plus) progressing to aMCI or AD. In addition to aging, lower education level and lower BMI were significantly associated with greater odds of SCD (plus) progressing to aMCI or AD patients, whereas mental work was a protective factor of SCD (plus) progressing to AD. Finally, AVLT is a sensitive indicator of the cognitive decline and impairment in SCD (plus) in relative to normal controls.Applied Ergonomics and Desig

    Direct microbial electron uptake as a mechanism for stainless steel corrosion in aerobic environments

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    Shewanella oneidensis MR-1 is an attractive model microbe for elucidating the biofilm-metal interactions that contribute to the billions of dollars in corrosion damage to industrial applications each year. Multiple mechanisms for S. oneidensis-enhanced corrosion have been proposed, but none of these mechanisms have previously been rigorously investigated with methods that rule out alternative routes for electron transfer. We found that S. oneidensis grown under aerobic conditions formed thick biofilms (∼50 µm) on stainless steel coupons, accelerating corrosion over sterile controls. H2 and flavins were ruled out as intermediary electron carriers because stainless steel did not reduce riboflavin and previous studies have demonstrated stainless does not generate H2. Strain ∆mtrCBA, in which the genes for the most abundant porin-cytochrome conduit in S. oneidensis were deleted, corroded stainless steel substantially less than wild-type in aerobic cultures. Wild-type biofilms readily reduced nitrate with stainless steel as the sole electron donor under anaerobic conditions, but strain ∆mtrCBA did not. These results demonstrate that S. oneidensis can directly consume electrons from iron-containing metals and illustrate how direct metal-to-microbe electron transfer can be an important route for corrosion, even in aerobic environments.Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Team Arjan Mo

    Spatial distribution of Dactylogyrus wunderi Bychowsky on gills of Abramis brama orientalis Berg (Leuciscinae) in Irtysh River, China

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    The spatial distribution of the monogenean Dactylogyrus wunderi Bychowsky, 1931 on the gill filaments of the bream Abramis brama orientalis Berg (Leuciscinae) inhabiting the Irtysh River of Xinjiang, China was investigated from June to July 2012. D. wunderi was identified by sequencing a fragment of its ITS rDNA region. Sixty-five fish were examined, with 55% testing positive for monogenean infection. The prevalence of the parasite in the left and right gill arches was 46% and 48%, respectively. In fish with a large body length, the prevalence of the parasite and the infection intensity did not significantly differ between the right and left gill arches but both were slightly higher in the former. Among the three size groups of fish (small, medium and large) the prevalence and the intensity of infection were lowest in fish with small body lengths. The distribution of the monogenean population in the host gills showed an aggregate distribution, with little change in the degree of aggregation, suggesting that most hosts were either not or only slightly infected by D. wunderi and that the parasite infected only a few hosts. In addition, differences in D. wunderi infections between gill arches of A. brama orientalis were not significant (P > 0.05).The spatial distribution of the monogenean Dactylogyrus wunderi Bychowsky, 1931 on the gill filaments of the bream Abramis brama orientalis Berg (Leuciscinae) inhabiting the Irtysh River of Xinjiang, China was investigated from June to July 2012. D. wunderi was identified by sequencing a fragment of its ITS rDNA region. Sixty-five fish were examined, with 55% testing positive for monogenean infection. The prevalence of the parasite in the left and right gill arches was 46% and 48%, respectively. In fish with a large body length, the prevalence of the parasite and the infection intensity did not significantly differ between the right and left gill arches but both were slightly higher in the former. Among the three size groups of fish (small, medium and large) the prevalence and the intensity of infection were lowest in fish with small body lengths. The distribution of the monogenean population in the host gills showed an aggregate distribution, with little change in the degree of aggregation, suggesting that most hosts were either not or only slightly infected by D. wunderi and that the parasite infected only a few hosts. In addition, differences in D. wunderi infections between gill arches of A. brama orientalis were not significant (P > 0.05)

    Patches structure succession based on spatial point pattern features in semi-arid ecosystems of the water-wind erosion crisscross region

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    Spatial point-pattern analysis can give insights to the underlying processes of patch succession and restoration. It is unclear whether inter-shrub competition determines patch succession. In this paper, we assessed the spatial patterns along patch succession using spatial statistics such as univariate and bivariate O-ring statistics, in the water-wind erosion crisscross region in semi-arid ecosystems of the Loess Plateau. Point pattern analysis results showed that there were no significant difference in three positions of the slope. The small and middle shrub patches were aggregatedly distributed in small spatial scale, meanwhile the large shrub patches were regularly distributed and dead shrub patches were randomly distributed. The small shrub patches were respectively aggregated to the middle and large patches at fine scales. Competition-induced regular distribution or negative relationship becomes obvious when analyzing the shift towards less aggregated perceptible effect of competition, a time component should always be included in spatial pattern-based inference of competition. Our results revealed that regular, clumped and random shrub patch patterns could occur, pending on size of shrub patches, and the shrub patches are distributed in different ways and they can present variant spatial point pattern features along patch size succession. (c) 2017 The Authors. Published by Elsevier B.V
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