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Parkinson disease is characterized by dopaminergic cell loss in the substantia nigra of the midbrain. There are various imaging markers for Parkinson disease. Recent advances in MRI have enabled elucidation of the underlying pathophysiologic changes in the nigral structure. This has contributed to accurate and early diagnosis and has improved disease progression monitoring. This article aims to review...
The spectrum of sleep disorders in parkinson disease: a review Annie C Lajoie, Anne-Louise Lafontaine, Marta Kaminska Chest 159 (2), 818-827, 2021 There is increasing interest in the effects of sleep and sleep disturbances on the brain, particularly in relation to aging and neurodegenerative processes. Parkinson disease (PD) is the second most common neurodegenerative disorder, with growing prevalence...
Importance The protective effects of physical activity (PA) against Parkinson disease (PD) development have been suggested; however, the association of PA with mortality in PD has rarely been investigated.
Objective To evaluate the association between PA and mortality in individuals with PD and determine how the amount and maintenance of PA are associated with mortality.
Design, Setting, and...
Parkinson disease (PD) is a prevalent neurodegenerative disease, in which the formation of misfolded and aggregated α‐synuclein is a key neuropathological hallmark. Recent studies reveal that extracellular vesicles such as exosomes present a potential mechanism for propagation of pathological α‐synuclein throughout the brain. The ability of exosomes to transport proteins and genetic material between...
Generally, underwater hull inspection have been conducted by human divers. It is an extremely dangerous task, and hence, can be a potential application for unmanned underwater vehicles. The operational safety and performance of in-water inspection can be significantly improved by introducing unmanned vehicle systems. This study addresses the development of an hover-capable autonomous underwater vehicle...
We propose an imaging sonar-based backtracking method as a navigation strategy for an underwater investigation of AUVs. The purpose of backtracking method is to reduce a drift error caused by the inaccuracy of navigation sensors when an AUV returns to its previous position. The AUV divides the trajectory into several intervals and returns to the previous position while correcting small drift error...
The MUSIC(MUltiple SIgnal Classification) method with high resolution is typically used to estimate far-field source bearing. When the source is located in the near-field, it can be applied by compensating the time-delay difference and the magnitude attenuation using spherical wave rules. However, it has a problem with complex calculations, such as eigen-decomposition of a matrix. In this paper, we...
This study aims at comparative analysis of ship speed-power performance based on the daily report and onboard logged sensor data. This paper shows how much difference exists between two results and proposes a proper methodology to analyze the ship performance. To evaluate and compare the performance, 130 days daily noon reports and logged sensor data from a bulk carrier were used and ISO 15016:2015[1],...
The use of elevation changes in an undulating terrain surface can be an effective alternative for vehicle navigation in GPS-denied underwater environments, since subsea terrain elevation data can be obtained using sonar systems. The performance of terrain-referenced navigation varies significantly depending on how informative a given terrain is, however it is not straightforward to quantify the amount...
The QARTOD methodology of a standard sequential string of tests on individual measurements has high applicability to constrained data systems. The QARTOD methodology has the benefit of a coherent and replicable test structure that enables relatively easy expansion into new measurements. However, as data streams become more complex the series of tests described becomes increasingly difficult to analyse...
It is known that a dysoxic water mass threatens oyster farming in Dangdong bay. A density current generator is planned to be installed to solve this problem. In this study, we reconstructed the tide level, physical field and dysoxic water mass in Dangdong bay by using numerical simulation and comparing with field measurements and investigated the effect of density current generator by installing it...
Physical environment is changing in the Pacific Ocean and it is well-known that the internal waves develop and propagate in the Pacific Ocean. Since the changing physical environment of the Pacific Ocean may influence the tidal phenomena in the coastal ocean, it will be worthwhile to know first how the tidal characteristics in its marginal seas changes. In this study we examine the long-term tidal...
In this paper, we propose a backtracking method of AUV based on optical and acoustic image evaluation. With the proposed method, the vehicle can record useful images on its path, and conduct backtracking efficiently and robustly even in turbid water. At each point during the exploration, AUV chooses better image between optical and acoustic image by feature detection. The chosen image is saved in...
The underwater vehicle-manipulator system (UVMS) generally has more degrees of freedom than those required to perform a given task. Because of these extra of degrees of freedom, UVMS has infinite combinations of joint velocities. In this paper, in order to generate the joint angle trajectories of the manipulator, a redundancy resolution is performed to minimize the distance between the position of...
The National Tsunami Warning Center (NTWC) and the Pacific Tsunami Warning Center (PTWC) collaborate to provide tsunami warning service and mutual backup to tsunami-threatened areas throughout the United States and many other countries throughout the world. With mostly home-grown analysis systems, NTWC staff rapidly locates, sizes, and otherwise characterizes major earthquakes. We determine each earthquake's...
Shell Exploration & Production Company is working with academic, non-profit, and federal stakeholders in the Gulf of Mexico to develop and implement long term environmental offshore monitoring programs. One such program, started in 2008 between Shell and the National Oceanic and Atmospheric Administration, has expanded to include new collaborators working together to operate multiple underwater...
The trend of unsustainable power consumption and large memory bandwidth demands in massively parallel multicore systems, with the advent of the big data era, has brought upon the onset of alternate computation paradigms utilizing heterogeneity, specialization, processor-in-memory and approximation. Approximate Computing is being touted as a viable solution for high performance computation by relaxing...
Routing algorithms can improve network performance by maximizing routing adaptiveness but can be problematic in the presence of endpoint congestion. Tree-saturation is a well-known behavior caused by endpoint congestion. Adaptive routing can, however, spread the congestion and result in thick branches of the congestion tree — creating Head-of-Line (HoL) blocking and degrading performance. In this...
In this paper, we propose boundary-preserving depth upsampling without texture copying artifacts and holes. Since high-resolution (HR) color images contain many edges and textures, they inevitably cause artifacts such as texture copying when they are used in depth upsampling. Thus, we perform rolling guidance filtering on HR color images before depth upsampling to preserve object boundaries in depth...
Quality of Experience (QoE) anomalies widely exist in all types of video services. As video services migrate to the Cloud, unique challenges occur to deploy video services in the Cloud environment. We study the QoE anomalies for users in a video service deployed in a production Cloud CDN. We use a QoE anomaly identification system, QRank, to identify anomalous systems. We consider Cloud CDN servers,...
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