In this work, we consider varying aspects of the stability of periodic traveling wave solutions to nonlinear dispersive equations. In particular, we are interested in deriving universal geometric criterion for the stability of particular third order nonlinear dispersive PDE’s. We begin by studying the spectral stability of such solutions to the generalized Korteweg-de Vries (gKdV) equation. Usi...

Background Patellar height has long been considered a risk factor for patellofemoral instability. However, recent pediatric literature demonstrated a reduction in patellar height measurements following medial patellofemoral ligament (MPFL) reconstruction. Purpose To assess the mean change in patellar height and the percentage of skeletally mature patients with patellar height ratios reduced t...

We study the spectral stability of a family of periodic standing wave solutions to the generalized KdV (g-KdV) in a neighborhood of the origin in the spectral plane using what amounts to a rigorous Whitham modulation theory calculation. In particular we are interested in understanding the role played by the null directions of the linearized operator in the stability of the traveling wave to per...

We study the spectral stability of a family of periodic standing wave solutions to the generalized KdV (g-KdV) in a neighborhood of the origin in the spectral plane using what amounts to a rigorous Whitham modulation theory calculation. In particular we are interested in understanding the role played by the null directions of the linearized operator in the stability of the traveling wave to per...

Local differences in the electrogastrographic (EGG) indices were studied. The indices include the spectral frequency, the instability factor (IF) of the spectral frequency, and the power content in addition to the usual power amplitude of 5 frequency groups as follows: the 1-cpm group (0-2.4), the 3-cpm group (2.5-4.9), the 6-cpm group (5.0-7.4), the 8-cpm group (7.5-9.9), and the 10-cpm group ...

BACKGROUND Investigating reproducibility and instability of deep inspiration breath hold (DIBH) in the prone position to reduce heart dose for left-sided whole breast irradiation. METHODS Thirty patients were included and underwent 2 prone DIBH CT-scans during simulation. Overlap indices were calculated for the ipsilateral breast, heart and lungs to evaluate the anatomical reproducibility of ...

BACKGROUND Both diabetes and obesity syndromes are recognized to promote lumbar vertebral instability, premature osteodegeneration, exacerbate progressive osteoporosis and increase the propensity towards vertebral degeneration, instability and deformation in humans. METHODS The influences of single-gene missense mutations, expressing either diabetes (db/db) or obese (ob/ob) metabolic syndrome...

introduction: assessing quality of life for patients with shoulder instability may be essential because of the negative impacts of the disease on patient’s life. the aim of the present study, therefore,  was  to  assess  the  internal  validity  and  consistency,  test-retest  reliability,  and convergent validity of the persian version of the oxford shoulder instability score (osis). material ...