statement of problem comprehensive diagnosis is regarded as an important base for orthodontic treatment. an effective way to achieve 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 norms of senior high school students in the city of hamed...

BACKGROUND AND PURPOSE In a previous investigation concerning the hemodynamic and metabolic changes over time displayed by sequential positron emission tomography (PET) in a middle cerebral artery (MCA) occlusion/reperfusion primate model, a metabolic threshold for irreversible ischemia could be identified (reduction of metabolic rate of oxygen [CMRO(2)] to approximately 60% of the contralatera...

Ambient occlusion (AO) is a popular technique for real-time as well as offline rendering. One of its benefits is a gain in efficiency due to the fact that occlusion and shading are decoupled which results in an average occlusion that modulates the surface shading. Its main drawback is a loss of realism due to the lack of directional occlusion and lighting. As a solution, the use of bent normals...

Primate lentiviruses (PLV) from closely related primate species have been observed to be more closely related to each other than to PLV from more distantly related primate species. The current explanation for this observation is the codivergence hypothesis; that is, the divergence of a virus lineage results from the divergence of the host lineage. We show that, alternatively, frequent cross-spe...

The information represented in the primate hippocampus is being analysed by making recordings in monkeys actively walking in the laboratory. In a sample of 352 cells recorded in this situation, no "place" cells have so far been found. Instead, we have found a considerable population of "spatial view" cells tuned to respond when the monkey looks at small parts of the environment. We have been ab...

purpose: to determine the frequency of risk factors for retinal vein occlusion (rvo) in patients referred to a private clinic in rasht during 1995-2001. methods: this cross-sectional study was conducted on all patients with rvo who were referred to the clinic. sex, age, hypertension (htn), cardiovascular diseases (cvd), diabetes mellitus (dm), hypercoagulable states, glaucoma, smoking, hyperlip...

Effective use of screen space and reduction of occlusion are important for usability. We present a toolkit to help a GUI manage space and occlusion by visual introspection. Rather than relying on a GUI’s internal model, our toolkit inspects a GUI’s visual appearance at the screen pixel level and computes maps to describe the GUI’s space and occlusion distribution. Moreover, we compare a GUI’s e...

Very large polygonal models are frequently used in scientific computing, mechanical engineering, or virtual medicine. An effective technique to handle these large models is occlusion culling. Like most large model techniques, occlusion culling trades overhead costs with the rendering costs of the possibly occluded geometry. In this paper, we present occlusion culling techniques for OpenSG. Thes...

In the visual system, large ensembles of neurons collectively sample visual space with receptive fields (RFs). A puzzling problem is how neural ensembles provide a uniform, high-resolution visual representation in spite of irregularities in the RFs of individual cells. This problem was approached by simultaneously mapping the RFs of hundreds of primate retinal ganglion cells. As observed in pre...