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We have tested the effectiveness of polyethylene glycol (PEG) to restore the integrity of neuronal membranes after mechanical damage secondary to severe traumatic brain injury (TBI) produced by a standardized head injury model in rats. We provide additional detail on the standardization of this model, particularly the use and storage of foam bedding that serves to both support the animal during the impact procedure-and as a dampener to the acceleration of the brass weight. Further, we employed a dye exclusion technique using ethidium bromide (EB; quantitative evaluation) and horseradish peroxidase (HRP; qualitative evaluation). Both have been successfully used previously to evaluate neural injury in the spinal cord since they enter cells when their plasma membranes are damaged. We quantified EB labeling (90 microM in 110 microL of sterile saline) after injection into the left lateral ventricle of the rat brain 2 h after injury. At six h after injection and 8 h after injury, the animals were sacrificed and the brains were analyzed. In the injured rat brain, EB entered cells lining and medial to the ventricles, particularly the axons of the corpus callosum. There was minimal EB labeling in uninjured control brains, limited to cells lining the luminal surfaces of the ventricles. Intravenous injections of PEG (1 cc of saline, 30% by volume, 2000 MW) immediately after severe TBI resulted in significantly decreased EB uptake compared with injured control animals. A similar result was achieved using the larger marker, HRP. PEG-treated brains closely resembled those of uninjured animals.

Brilliant iridescent colors occur on many biological objects. Current RGB-based graphics renderers are not sufficient to simulate such phenomena. This is because biological iridescences are caused by interference or diffraction, which requires wavelength information to describe. In this article, we propose an iridescent shading process that allows to render biological iridescences with RGB-based renderers. The key ideas are to construct spectra from colors and to use a wavelength-dependent model to describe iridescences. A novel model for iridescent illumination due to multilayer interference is developed based on analytic calculation and numerical simulation, and is simplified for practical rendering. The iridescent shading process is implemented using RenderMan embedded in Maya. Iridescent Morpho butterflies and ground beetles are rendered as examples to test the proposed techniques.

Abstract-The Android framework has raised increased security concerns with regards to its access control enforcement. Particularly, existing research efforts successfully demonstrate that framework security checks are not always consistent across appaccessible APIs. However, existing efforts fall short in addressing peculiarities that characterize the complex Android access control and the diversity introduced by the heavy vendor customization. In this paper, we develop a new analysis framework AceDroid that models Android access control in a path-sensitive manner and normalizes diverse checks to a canonical form. We applied our proposed modeling to perform inconsistency analysis for 12 images. Our tool proved to be quite effective, enabling to detect a significant number of inconsistencies introduced by various vendors and to suppress substantial false alarms. Through investigating the results, we uncovered high impact attacks enabling to write a key logger, send premium sms messages, bypass user restrictions, perform a major denial of services and other critical operations.

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A common observation about confocal microscopy images is that lower image stacks have lower voxel intensities and are usually blurred in comparison with the upper ones. The key reasons are light absorption and scattering by the objects and particles in the volume through which light passes. This report proposes a new technique to reduce such noise impacts in terms of an adaptive intensity compensation and structural sharpening algorithm. With these image-processing procedures, effective 3D rendering techniques can be applied to faithfully visualize confocal microscopy data.

Iridescent colors of optical disks are caused by light diffraction from their surface microstructure. This paper proposes a diffractive illumination model for optical disks based on their physical structure and the superposition principle of light waves. This model includes contributions due to diffractive and non-diffractive factors. For the diffractive part, we first model the pit periodicity for optical disks by using identical spheres and then simplify their distribution by uniform groups of spheres. We also propose and prove the condition for highlights on illuminated grooved surfaces; this condition provides the non-diffractive contribution. The rendered images using this model achieve excellent agreement with photographs of real optical disks.