A comparative immunohistochemical study of Ki-67 expression in adenomatoid odontogenic tumour, unicystic ameloblastoma and dentigerous cyst

Magister Chirurgiae Dentium - MChDThe aim of this study was to investigate the biological profile oftheAOT by comparing the Ki-67 proliferative indices of the AOT, Unicystic Ameloblastoma (UA) and Dentigerous Cyst (DC) using ImmunoRatio® software. Adenomatoid Odontogenic Tumours (AOTs) are classified as benign epithelial odontogenic neoplasms with mature fibrous stroma, without odontogenic mesenchyme. However these lesions, like odontomes, occur almost exclusively during the final period of odontogenesis, and clinically behave like self-limiting hamartomatous lesions. Histologically they seem to arise from the lining of dental follicle

Nonstationary Stochastic Resonance in a Single Neuron-Like System

Stochastic resonance holds much promise for the detection of weak signals in the presence of relatively loud noise. Following the discovery of nondynamical and of aperiodic stochastic resonance, it was recently shown that the phenomenon can manifest itself even in the presence of nonstationary signals. This was found in a composite system of differentiated trigger mechanisms mounted in parallel, which suggests that it could be realized in some elementary neural networks or nonlinear electronic circuits. Here, we find that even an individual trigger system may be able to detect weak nonstationary signals using stochastic resonance. The very simple modification to the trigger mechanism that makes this possible is reminiscent of some aspects of actual neuron physics. Stochastic resonance may thus become relevant to more types of biological or electronic systems injected with an ever broader class of realistic signals.Comment: Plain Latex, 7 figure

Preface

Computer Graphics, Imaging and Visualization (CGiV) combined are used in some form or shape in most application in this age. New applications show strong trends from graphics, imaging, and visualisation. There are exciting explorations of theories and applications to a wide range of disciplines including social media, geo-sociology, health, business, security and more. Statistical analysis of literature illustrates that the chasm between academia and industries is abridged as applications becoming more innovative and drives new research activities

Computer Graphics, Imaging & Visualization — New Techniques and Trends

Computer graphics, imaging and visualization (CGiV) combined are used in some form or shape in most applications in this age. New applications show strong trends from graphics, imaging, and visualization. There are exciting explorations of theories and applications to a wide range of disciplines including social media, geo-sociology, health, business, security and more. Statistical analysis of literature illustrates that the chasm between academia and industries is being abridged as applications become more innovative and drive new research activities. The collection in this volume has the latest contributions from scientists, artists, and users from a cross section of disciplines in the area of computer graphics, imaging, and visualization. Though the classification is somewhat difficult because of the overlapping nature of the subject, there are three themes of graphics, imaging and visualisation running through this book. Chapters contribute towards different new techniques, applications, and tools within the theme of the book. The book is designed to have the best possible utility for researchers, computer scientists, practicing engineers, and many others around the globe. It will also be equally and extremely useful for graduate students in the areas of computer science, engineering, and other computational science disciplines

Multiple imaging by gravitational waves

Gravitational waves act like lenses for the light propagating through them. This phenomenon is described using the vector formalism employed for ordinary gravitational lenses, which was proved to be applicable also to a non-stationary spacetime, with the appropriate modifications. In order to have multiple imaging, an approximate condition analogous to that for ordinary gravitational lenses must be satisfied. Certain astrophysical sources of gravitational waves satisfy this condition, while the gravitational wave background, on average, does not. Multiple imaging by gravitational waves is, in principle, possible, but the probability of observing such a phenomenon is extremely low.Comment: 23 pages, LaTeX, no figures, to appear in Int. J. Mod. Phys.

Preface

Computer Graphics, Imaging and Visualization (CGiV) combined are used in some form or of the applications in this age and time. New applications show strong trends from graphics, imaging, and visualisation. There are exciting explorations of theories and applications to a wide range of disciplines including social media, geo-sociology, health, business, security and more. Statistical analysis of literature illustrates that the chasm between academia and industries is abridged as applications becoming more innovative and driving new research activities

Non-chaotic dynamics in general-relativistic and scalar-tensor cosmology

In the context of scalar-tensor models of dark energy and inflation, the dynamics of vacuum scalar-tensor cosmology are analysed without specifying the coupling function or the scalar field potential. A conformal transformation to the Einstein frame is used and the dynamics of general relativity with a minimally coupled scalar field are derived for a generic potential. It is shown that the dynamics are non-chaotic, thus settling an existing debate.Comment: 20 pages, LaTeX, to appear in Class. Quantum Gra

Complete constraints on a nonminimally coupled chaotic inflationary scenario from the cosmic microwave background

We present complete constraints imposed from observations of the cosmic microwave background radiation (CMBR) on the chaotic inflationary scenario with a nonminimally coupled inflaton field proposed by Fakir and Unruh (FU). Our constraints are complete in the sense that we investigate both the scalar density perturbation and the tensor gravitational wave in the Jordan frame, as well as in the Einstein frame. This makes the constraints extremely strong without any ambiguities due to the choice of frames. We find that the FU scenario generates tiny tensor contributions to the CMBR relative to chaotic models in minimal coupling theory, in spite of its spectral index of scalar perturbation being slightly tilted. This means that the FU scenario will be excluded if any tensor contributions to CMBR are detected by the forthcoming satellite missions. Conversely, if no tensor nature is detected despite the tilted spectrum, a minimal chaotic scenario will be hard to explain and the FU scenario will be supported.Comment: 7 pages, no figure, RevTeX, to appear in Phys.Rev. D59 (Mar. 15, 1999

Nonstationary Stochastic Resonance

It is by now established that, remarkably, the addition of noise to a nonlinear system may sometimes facilitate, rather than hamper the detection of weak signals. This phenomenon, usually referred to as stochastic resonance, was originally associated with strictly periodic signals, but it was eventually shown to occur for stationary aperiodic signals as well. However, in several situations of practical interest, the signal can be markedly nonstationary. We demonstrate that the phenomenon of stochastic resonance extends to nonstationary signals as well, and thus could be relevant to a wider class of biological and electronic applications. Building on both nondynamic and aperiodic stochastic resonance, our scheme is based on a multilevel trigger mechanism, which could be realized as a parallel network of differentiated threshold sensors. We find that optimal detection is reached for a number of thresholds of order ten, and that little is gained by going much beyond that number. We raise the question of whether this is related to the fact that evolution has favored some fixed numbers of precisely this order of magnitude in certain aspects of sensory perception.Comment: Plain Latex, 6 figure

Bending of Light by Gravity Waves

We describe the statistical properties of light rays propagating though a random sea of gravity waves and compare with the case for scalar metric perturbations from density inhomogeneities. For scalar fluctuations the deflection angle grows as the square-root of the path length $D$ in the manner of a random walk, and the rms displacement of a ray from the unperturbed trajectory grows as $D^{3/2}$. For gravity waves the situation is very different. The mean square deflection angle remains finite and is dominated by the effect of the metric fluctuations at the ends of the ray, and the mean square displacement grows only as the logarithm of the path length. In terms of power spectra, the displacement for scalar perturbations has $P(k) \propto 1/ k^4$ while for gravity waves the trajectories of photons have $P(k) \propto 1/k$ which is a scale-invariant or `flicker-noise' process, and departures from rectilinear motion are suppressed, relative to the scalar case, by a factor $\sim (\lambda / D)^{3/2}$ where $\lambda$ is the characteristic scale of the metric fluctuations and $D$ is the path length. This result casts doubt on the viability of some recent proposals for detecting or constraining the gravity wave background by astronomical measurements.Comment: 14 pages, aastex, submitted to Astrophysical Journa