8 research outputs found
Electrocardiographic Changes in a Patient With Pulmonary Embolism and Septic Shock
Various electrocardiography (ECG) abnormalities have been reported in patients who present with pulmonary embolism (PE). Severe sepsis is also associated with ECG changes that may mimic ST elevation myocardial infarction. We report a case of an elderly patient with PE and septic shock associated with striking ECG changes
Static and dynamic properties of helical spin chains
A detailed quantitative study of a classical Heisenberg chain with nearest- and next-nearest-neighbor interaction is presented. For a wide range of interaction strength, this model leads to helical structures and the effects of this peculiar structure on the static and dynamic properties is extensively discussed. The most striking feature is the presence of both a central resonance and a spin-wave peak at fairly low temperatures.
Molecular dynamics simulation on flows in nano-ribbed and nano-grooved channels
We present molecular dynamics simulation results on fluid and transport properties for nanochannel flows. The upper channel wall is constructed from periodic roughness elements and flows are simulated both in longitudinal (ribs) and transverse (grooves) direction and are compared to respective flat-wall channel flows. Various wall/fluid interaction strength ratios are considered for the simulations, covering typical hydrophilic and hydrophobic channels. We show that groove orientation (ribs and grooves) has a primitive effect on flow mainly due to slip length increase in a ribbed-wall channel. The transport properties of the fluid are significantly affected by wall wettability, as, in flows past an hydrophobic wall, the diffusion coefficient presents anisotropy, shear viscosity attains a minimum value and thermal conductivity increases. © 2015 Springer-Verlag Berlin Heidelber
A quasi-continuum multi-scale theory for self-diffusion and fluid ordering in nanochannel flows
We present a quasi-continuum self-diffusion theory that can capture the ordering effects and the density variations that are predicted by non-equilibrium molecular dynamics (NEMD) in nanochannel flows. A number of properties that affect fluid ordering in NEMD simulations are extracted and compared with the quasi-continuum predictions. The proposed diffusion equation requires the classic diffusion coefficient D and a micro structural internal length g that relates directly to the shape of the molecular potential of the NEMD calculations. The quasi-continuum self-diffusion theory comes as an alternative to atomistic simulation, bridging the gap between continuum and atomistic behavior with classical hydrodynamic relations and reduces the computational burden as compared with fully atomistic simulations