On discretization in time in simulations of particulate flows

We propose a time discretization scheme for a class of ordinary differential equations arising in simulations of fluid/particle flows. The scheme is intended to work robustly in the lubrication regime when the distance between two particles immersed in the fluid or between a particle and the wall tends to zero. The idea consists in introducing a small threshold for the particle-wall distance below which the real trajectory of the particle is replaced by an approximated one where the distance is kept equal to the threshold value. The error of this approximation is estimated both theoretically and by numerical experiments. Our time marching scheme can be easily incorporated into a full simulation method where the velocity of the fluid is obtained by a numerical solution to Stokes or Navier-Stokes equations. We also provide a derivation of the asymptotic expansion for the lubrication force (used in our numerical experiments) acting on a disk immersed in a Newtonian fluid and approaching the wall. The method of this derivation is new and can be easily adapted to other cases

Biomarker Report from the Phase II Lamotrigine Trial in Secondary Progressive MS - Neurofilament as a Surrogate of Disease Progression

This work was supported by National MS Society (USA) under the Promise 2010 initiative and the MS Society of Great Britain and Northern Ireland as part of exploratory analysis for the UK MS Clinical Trial Network. VL is supported by Italian Minister of Health grant for young researcher 2008

Masquerade - Abstract

A 68 year-old man from Nicaragua, with a past medical history of diabetes and hypertension, presented with a one-year history of right-sided headaches, diplopia, and a four-month history of sudden vision loss in his right eye. In Nicaragua, a head CT and an angiogram had revealed a sphenoid wing and cavernous sinus lesion, suspected to be a meningioma, as well as occlusion of the right internal carotid artery. He was sent to the United States for possible radiation treatment. At the time of presentation in the United States, the patient also reported involvement of the left eye. He had no light perception in the right eye and a constricted visual field in the left eye. A right afferent pupillary defect was noted, along with decreased sensation in the V1 distribution on the right side. A procedure was performed

Masquerade - Presentation PPT

A 68 year-old man from Nicaragua, with a past medical history of diabetes and hypertension, presented with a one-year history of right-sided headaches, diplopia, and a four-month history of sudden vision loss in his right eye. In Nicaragua, a head CT and an angiogram had revealed a sphenoid wing and cavernous sinus lesion, suspected to be a meningioma, as well as occlusion of the right internal carotid artery. He was sent to the United States for possible radiation treatment. At the time of presentation in the United States, the patient also reported involvement of the left eye. He had no light perception in the right eye and a constricted visual field in the left eye. A right afferent pupillary defect was noted, along with decreased sensation in the V1 distribution on the right side. A procedure was performed

Unilateral Fourth Nerve Palsy due to Presumed Metastatic Melanoma

An 81-year-old man with a history of metastatic melanoma presented with sudden onset of painless, binocular vertical diplopia. The clinical examination was consistent with a right fourth nerve palsy. An MRI of the head revealed a mass dorsal to the right tectum at the level of the inferior colliculus. An MRI just 4 months prior did not show a lesion in that location. An MRA of the head did not show an aneurysm. This is a rare case of an isolated fourth nerve palsy believed to be due to metastatic melanoma compressing the nerve along the dorsal midbrai

Unilateral Fourth Nerve Palsy due to Presumed Metastatic Melanoma

An 81-year-old man with a history of metastatic melanoma presented with sudden onset of painless, binocular vertical diplopia. The clinical examination was consistent with a right fourth nerve palsy. An MRI of the head revealed a mass dorsal to the right tectum at the level of the inferior colliculus. An MRI just 4 months prior did not show a lesion in that location. An MRA of the head did not show an aneurysm. This is a rare case of an isolated fourth nerve palsy believed to be due to metastatic melanoma compressing the nerve along the dorsal midbrain