Clemson University

About: Clemson University is a education organization based out in Clemson, South Carolina, United States. It is known for research contribution in the topics: Population & Control theory. The organization has 20556 authors who have published 42518 publications receiving 1170779 citations. The organization is also known as: Clemson Agricultural College of South Carolina.

A Survey of Surface Reconstruction from Point Clouds

Abstract: The area of surface reconstruction has seen substantial progress in the past two decades. The traditional problem addressed by surface reconstruction is to recover the digital representation of a physical shape that has been scanned, where the scanned data contain a wide variety of defects. While much of the earlier work has been focused on reconstructing a piece-wise smooth representation of the original shape, recent work has taken on more specialized priors to address significantly challenging data imperfections, where the reconstruction can take on different representations-not necessarily the explicit geometry. We survey the field of surface reconstruction, and provide a categorization with respect to priors, data imperfections and reconstruction output. By considering a holistic view of surface reconstruction, we show a detailed characterization of the field, highlight similarities between diverse reconstruction techniques and provide directions for future work in surface reconstruction.

Tissue reaction to three ceramics of porous and non-porous structures.

Abstract: In this investigation, ceramics were studied to determine their role as rigid, abrasive implants in soft, living tissue. Discs and tubes of three ceramics, CaO·Al2O3, CaO·TiO2, and CaO·ZrO2, were introduced as porous and non-porous structures into muscle and connective tissue sites in rabbits. The animals were observed grossly to determine the duration of redness and swelling following surgery, and samples were retrieved at 1 week, 3 months, 6 months, and 9 months after implantation. A mild, acute inflammatory response immediately followed the implantation of all three materials in both the porous and non-porous forms. Histological sections of the ceramics and surrounding tissue, cut and stained for light microscopy, demonstrated the absence of inflammatory cells and revealed the normal morphology and organization of the cells present around all types of implants tested. Tissue around discs of porous ceramics healed faster and exhibited thinner fibrous encapsulations than with impervious discs of the same material. Healthy fibrous connective tissue with an ample blood supply occupied those implants with pores of 45–100 mμ, and even more rapidly filled the samples with a 100- to 150-μ pore size. The tissue ingrowth and tight adherence to the porous samples was believed responsible for the more moderate response to porous implants. No adverse responses of any kind were observed, except in a very few, atypical specimens.

Macrophage/particle interactions: Effect of size, composition and surface area

Abstract: Particulate wear-debris are detected in histiocytes/macrophages of granulomatous tissues adjacent to loose joint prostheses. Such cell-particle interactions have been simulated in vitro by challenging macrophages with particles dosed according to weight percent, volume percent, and number of particles. Each of these dosage methods has inherent shortcomings due to varying size and density of challenging particles of different compositions. In this study we challenged P388D1 macrophages with titania and polystyrene particles (< 2 microns), with dosage based on the ratio of the surface area of the particles to the surface area of the cells. The effect of size and composition on (1) the bone resorbing activity, (2) fibroblast proliferation, and (3) secretion of IL-1 and PGE2 was determined. Macrophage response to particulate debris appears to be dependent on particle size, composition, and dose as given by surface area ratio. P388D1 macrophages challenged with titania particles released IL-1, but did not stimulate fibroblasts. Inhibition of macrophage DNA synthesis at higher surface area ratios suggests cell damage or death. Particle-stimulated cells increased bone resorption up to 125% of controls but released only basal levels of PGE2. Macrophages stimulated by wear particles are expected to synthesize numerous factors affecting events in the bone-implant interface. Using the concept of surface area ratio allows us to study and compare such cellular responses to wear particles in a standardized manner.

High‐Dielectric‐Constant Silver–Epoxy Composites as Embedded Dielectrics

Abstract: We report the synthesis of an epoxy-based composite containing randomly distributed silver nanoparticles with a narrow size distribution centered around 40nm. The surface of the Ag nanoparticles is coated with a thin layer of mercaptosuccinic acid (MSA) in order to promote formation of the Ag-epoxy while retaining flexibility of the polymer matrix. This composite is the basis of a prototype capacitor formed by spin coating the synthesized Ag-epoxy (40nm Ag) mixture onto a gold-deposited aluminum substrate. A series of Ag-epoxy composites with various Ag volume fractions was investigated in order to determine the composition associated with optimum capacitor performance. The high dielectric constant (> 300) and relatively low dielectric loss (<0.05) render this material of promising potential for embedded capacitor applications.