scholarly journals Resting State Alpha Electroencephalographic Rhythms Are Differently Related to Aging in Cognitively Unimpaired Seniors and Patients with Alzheimer’s Disease and Amnesic Mild Cognitive Impairment

2021 ◽  
pp. 1-30
Author(s):  
Claudio Babiloni ◽  
Raffaele Ferri ◽  
Giuseppe Noce ◽  
Roberta Lizio ◽  
Susanna Lopez ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Cognitive Impairment ◽  
Mild Cognitive Impairment ◽  
Resting State ◽  
Diagnostic Biomarkers ◽  
Eyes Closed ◽  
Topographical Effects ◽  
And Gender ◽  
International Archive

Background: In relaxed adults, staying in quiet wakefulness at eyes closed is related to the so-called resting state electroencephalographic (rsEEG) rhythms, showing the highest amplitude in posterior areas at alpha frequencies (8–13 Hz). Objective: Here we tested the hypothesis that age may affect rsEEG alpha (8–12 Hz) rhythms recorded in normal elderly (Nold) seniors and patients with mild cognitive impairment due to Alzheimer’s disease (ADMCI). Methods: Clinical and rsEEG datasets in 63 ADMCI and 60 Nold individuals (matched for demography, education, and gender) were taken from an international archive. The rsEEG rhythms were investigated at individual delta, theta, and alpha frequency bands, as well as fixed beta (14–30 Hz) and gamma (30–40 Hz) bands. Each group was stratified into three subgroups based on age ranges (i.e., tertiles). Results: As compared to the younger Nold subgroups, the older one showed greater reductions in the rsEEG alpha rhythms with major topographical effects in posterior regions. On the contrary, in relation to the younger ADMCI subgroups, the older one displayed a lesser reduction in those rhythms. Notably, the ADMCI subgroups pointed to similar cerebrospinal fluid AD diagnostic biomarkers, gray and white matter brain lesions revealed by neuroimaging, and clinical and neuropsychological scores. Conclusion: The present results suggest that age may represent a deranging factor for dominant rsEEG alpha rhythms in Nold seniors, while rsEEG alpha rhythms in ADMCI patients may be more affected by the disease variants related to earlier versus later onset of the AD.

scholarly journals Geospatial Assessment of the Post-Earthquake Hazard of the 2017 Pohang Earthquake Considering Seismic Site Effects

2018 ◽  
Vol 7 (9) ◽  
pp. 375 ◽  
Author(s):  
Han-Saem Kim ◽  
Chang-Guk Sun ◽  
Hyung-Ik Cho
Keyword(s):  
Site Effects ◽  
Focal Depth ◽  
Earthquake Hazard ◽  
Earthquake Damage ◽  
Site Classification ◽  
Topographical Effects ◽  
Seismic Site Effects ◽  
Moderate Earthquake ◽  
Seismic Amplification ◽  
Earthquake Moment

The 2017 Pohang earthquake (moment magnitude scale: 5.4) was South Korea’s second strongest earthquake in decades, and caused the maximum amount of damage in terms of infrastructure and human injuries. As the epicenters were located in regions with Quaternary sediments, which involve distributions of thick fill and alluvial geo-layers, the induced damages were more severe owing to seismic amplification and liquefaction. Thus, to identify the influence of site-specific seismic effects, a post-earthquake survey framework for rapid earthquake damage estimation, correlated with seismic site effects, was proposed and applied in the region of the Pohang earthquake epicenter. Seismic zones were determined on the basis of ground motion by classifying sites using the multivariate site classification system. Low-rise structures with slight and moderate earthquake damage were noted to be concentrated in softer sites owing to the low focal depth of the site, topographical effects, and high frequency range of the mainshocks.

scholarly journals Chemical and Topographical Effects on Cell Differentiation and Matrix Elasticity in a Corneal Stromal Layer Model

2012 ◽  
Vol 22 (17) ◽  
pp. 3641-3649 ◽  
Author(s):  
Samantha L. Wilson ◽  
Ian Wimpenny ◽  
Mark Ahearne ◽  
Saaeha Rauz ◽  
Alicia J. El Haj ◽  
...  
Keyword(s):  
Cell Differentiation ◽  
Layer Model ◽  
Matrix Elasticity ◽  
Topographical Effects ◽  
Stromal Layer

Grazing intensity and micro-topographical effects on some nitrogen and carbon pools and fluxes in sheep-grazed hill country in New Zealand

2016 ◽  
Vol 217 ◽  
pp. 22-32 ◽  
Author(s):  
C.J. Hoogendoorn ◽  
P.C.D. Newton ◽  
B.P. Devantier ◽  
B.A. Rolle ◽  
P.W. Theobald ◽  
...  
Keyword(s):  
New Zealand ◽  
Grazing Intensity ◽  
Carbon Pools ◽  
Hill Country ◽  
Topographical Effects

scholarly journals Track Deflection of Typhoon Nesat (2017) as Realized by Multiresolution Simulations of a Global Model

2019 ◽  
Vol 147 (5) ◽  
pp. 1593-1613 ◽  
Author(s):  
Ching-Yuang Huang ◽  
Chien-Hsiang Huang ◽  
William C. Skamarock
Keyword(s):  
Large Scale ◽  
Model Simulation ◽  
Global Model ◽  
Mountain Range ◽  
Latent Heating ◽  
The West ◽  
Topographical Effects ◽  
Typhoon Center ◽  
Underlying Mechanisms ◽  
Northern Taiwan

Abstract Typhoon Nesat (2017) headed west-northwestward toward Taiwan but took a relatively larger northward deflection about 300 km away and then a leftward deflection after landfall at northern Taiwan. A global model MPAS, employing a multiresolution of 60–15–3 km mesh, is used to investigate the underlying mechanisms of the track changes. The global model simulations are capable of resolving the detailed topographical effects of the Central Mountain Range (CMR) in Taiwan, giving reasonable 5 day tracks in agreement with the observations for Typhoons Soudelor (2015) and Megi (2016), and comparing better with the observed deflection of Nesat (2017) than the regional model simulation of WRF. Sensitivity experiments indicate that flattening the CMR only partially reduces the track deflection of Nesat, while the elimination of the initial cyclone over the South China Sea disables the possible Fujiwhara effect and leads to a southward-biased track with much weaker northward deflection. The northward deflection of Nesat is mainly in response to the wavenumber-1 (WN-1) horizontal PV advection as the southerly flow east of the typhoon center is enhanced by convergence with the outer cyclonic typhoon flow and the large-scale southwesterlies. Upward motions and PV in the troposphere thus are much stronger to the east of the center than to the west, resulting in westward translation induced by negative WN-1 vertical PV advection but eastward translation induced by positive WN-1 vertical differential latent heating to the east. Near landfall, with stronger upward motions produced over the northern CMR, vertical differential latent heating averaged in 3–8-km height becomes negative and thus retards the westward translation.

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