Results 51 to 60 of about 25,108,413 (282)

Gravity‐Dependent Modulation of Downbeat Nystagmus: Insights From Velocity‐Storage Dysfunction

Annals of Clinical and Translational Neurology, EarlyView.
ABSTRACT Objective Downbeat nystagmus varies with head position, a phenomenon termed gravity‐dependent modulation. We aimed to clarify its mechanism using a velocity‐storage model. Methods In 10 patients with downbeat nystagmus due to cerebellar disorders, we recorded eye movements at different pitch‐ and roll‐axis head positions.
Ji‐Hyung Park, Eun‐Hyuk Choi, Jorge Otero‐Millan, David S. Zee, Jeong‐Yoon Choi, Ji‐Soo Kim   +5 more
wiley   +1 more source

Utilizing the Two-Way Wave Equation: Reverse Time Pre-Stack Depth Migration

ASEG Extended Abstracts, 2007
Reverse time pre-stack depth migration, which uses the two-way acoustic wave equation, is not a new concept. Conventionally the method has been very computationally intensive and, therefore, has been considered impractical for production 3D depth imaging projects.
Matthew H. Karazincir, Clive M. Gerrard, Andrew Long   +2 more
openaire   +1 more source

A Robust and Accurate Traveltime Calculation from Frequency-domain Two-way Wave-equation Modeling Algorithm [PDF]

Geosystem Engineering, 2004
ABSTRACT We improve the accuracy and stability of traveltime calculation method using frequency-domain modeling algorithm. We perform a parameter analysis to obtain the optimum combination of frequency and damping factor and thus improve the accuracy of traveltime. Then we obtain the empirical formula for our numerical algorithm. Lastly, we propose the
Yilong Qin, Seungwon Ko, Changsoo Shin, Zhongjie Zhang, Youngtak Seo, Uk Han, Yun Chen   +6 more
openaire   +1 more source

Rheumatoid Arthritis and Coronary Artery Calcium Progression: A Case Cohort Analysis From ELSA‐Brasil

Arthritis Care &Research, EarlyView.
Objective To investigate the association between rheumatoid arthritis (RA) and coronary artery calcium (CAC) prevalence, incidence, and progression over four years in adults without prior cardiovascular disease. Methods A case‐cohort study within the Brazilian Longitudinal Study of Adult Health (ELSA‐Brasil) included 585 participants (86 patients with ...
Patrícia Fonseca Estrada, Marcos Rafael N. Cavalcante, Itamar de Souza Santos, Márcio S. Bittencourt, Vandrize Meneghini, Paulo A. Lotufo, Alessandra C. Goulart, Isabela M. Bensenor   +7 more
wiley   +1 more source

Finite element heterogeneous multiscale methods for the wave equation [PDF]

, 2013
Wave phenomena appear in a wide range of applications such as full-waveform seismic inversion, medical imaging, or composite materials. Often, they are modeled by the acoustic wave equation.
Stohrer, Christian
core   +1 more source

The Avoidance of the Little Sibling of the Big Rip Abrupt Event by a Quantum Approach

Galaxies, 2018
We address the quantisation of a model that induces the Little Sibling of the Big Rip (LSBR) abrupt event, where the dark energy content is described by means of a phantom-like fluid or a phantom scalar field. The quantisation is done in the framework of
Imanol Albarran, Mariam Bouhmadi-López, Franciso Cabral, Prado Martín-Moruno   +3 more
doaj   +1 more source

Individuals With Multijoint Osteoarthritis Demonstrate Larger Longitudinal Declines in Frailty: Data From the Canadian Longitudinal Study on Aging

Arthritis Care &Research, EarlyView.
Objective The aim of this study was to test the hypothesis that multijoint osteoarthritis would modify the relation between time and frailty progression, in which more affected joints would lead to larger declines over six years compared to those without osteoarthritis using data from the Canadian Longitudinal Study on Aging.
Carson Halliwell, Rebecca Moyer, Myles W. O'Brien   +2 more
wiley   +1 more source

Wave-equation Qs Inversion of Skeletonized Surface Waves [PDF]

, 2017
We present a skeletonized inversion method that inverts surface-wave data for the Qs quality factor. Similar to the inversion of dispersion curves for the S-wave velocity model, the complicated surface-wave arrivals are skeletonized as simpler data ...
Dutta, Gaurav, Li, Jing, Schuster, Gerard T.   +2 more
core   +1 more source

Microvascular Damage Is Associated With Carotid Wall Structural Changes in Systemic Sclerosis: A Capillaroscopy and Ultrasound‐Based Observational Study

Arthritis Care &Research, EarlyView.
Objective Systemic sclerosis (SSc) is characterized by cardiovascular risk excess not fully explained by traditional factors. Whether the severity of microvascular damage correlates with structural subclinical atherosclerosis remains unclear. We investigated the relationship between nailfold videocapillaroscopy (NVC) abnormalities and carotid ...
Eugenio Capparelli, Luca Clerici, Francesco Lapia, Giusy C. Moltisanti, Eleonora Zaccara, Greta Pellegrino, Daniela Bompane, Francesca Capelli, Letizia Ferrami, Laura Castelnovo, Antonio Tamburello, Maria Sole Chimenti, Paola Faggioli, Antonino Mazzone   +13 more
wiley   +1 more source

Factorization of second-order strictly hyperbolic operators with logarithmic slow scale coefficients and generalized microlocal approximations

Electronic Journal of Differential Equations, 2018
We give a factorization procedure for a strictly hyperbolic partial differential operator of second order with logarithmic slow scale coefficients. From this we can microlocally diagonalize the full wave operator which results in a coupled system of ...
Martina Glogowatz
doaj