We present four cases of hydrocephalus caused by occlusion of foramen of Magendie associated with Chiari Type I malformation and syringomyelia. The aim of this study is to evaluate the results of surgical treatment via fourth ventriculostomy with catheter from the fourth ventricle to the upper cervical subarachnoid space. Obstructive tetraventricular hydrocephalus due to occlusion of the forami...

We introduce an approximate yet visually pleasant ambient occlusion approximation running on real-time graphics hardware. Our method is a multi-pass algorithm that separates the ambient occlusion problem into high-frequency, detailed ambient occlusion and low-frequency, distant ambient occlusion domains, both capable of running independently and in parallel. The high-frequency detailed approach...

In this paper, we propose a novel occlusion invariant face recognition algorithm based on Selective Local Nonnegative Matrix Factorization (S-LNMF) technique. The proposed algorithm is composed of two phases; the occlusion detection phase and the selective LNMF-based recognition phase. We use local approach to effectively detect partial occlusion in the input face image. A face image is first d...

a Department of Biology, University of Maryland, College Park, MD, U.S.A. b Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA, U.S.A. c Center for Geospatial Research, University of Georgia, Athens, GA, U.S.A. d Yerkes National Primate Research Center, Emory University, Atlanta, GA, U.S.A. e Goddard Space Flight Center, NASA, Greenbelt, MD, U.S.A. f Department ...

deep brain stimulation (dbs) is a neurosurgical procedure that enables brain structures to be stimulated electrically by a pacemaker implanted under the skin. in the 1980s, over a decade after its first use in pain, implantable dbs of the thalamus was performed to suppress tremor in parkinson’s disease (pd) refractory to drug treatments. primate-based research soon afterwards identified the sub...

statement of problem comprehensive diagnosis is regarded as an important base for orthodontic treatment. an effective way to reach a correct diagnosis is to compare the craniofacial skeleton of patients with normal cases in the same race through lateral cephalograms. purpose the present study was designed to determine the cephalometric standards of senior high school students in the city of ham...

purpose: to determine the effect of intravitreal triamcinolone (ivt) injection on visual acuity in patients with ischemic central retinal occlusion (crvo). methods: this randomized clinical trial was performed on patients with ischemic crvo referred to the retina clinic at feiz hospital in 2007-2008. inclusion criteria were: duration of crvo less than one month, normal iop, no sign of diabetic ...

We have recently introduced the concept of C-space entropy as a measure of knowledge of C-space for sensor-based path planning and exploration for general robot-sensor systems [1, 2, 3, 5]. The robot plans the next sensing action to maximally reduce the expected C-space entropy, also called the maximal expected entropy reduction, or MER criterion. The expected C-space entropy computation, howev...

Perinatal asphyxia is a leading cause of brain injury in neonates, occurring in 2–4 per 1,000 live births, and there are limited treatment options. Because of their similarity to humans, nonhuman primates are ideal for performing preclinical tests of safety and efficacy for neurotherapeutic interventions. We previously developed a primate model of acute perinatal asphyxia using 12–15 min of umb...

BACKGROUND Optic flow is an important cue for object detection. Humans are able to perceive objects in a scene using only kinetic boundaries, and can perform the task even when other shape cues are not provided. These kinetic boundaries are characterized by the presence of motion discontinuities in a local neighbourhood. In addition, temporal occlusions appear along the boundaries as the object...