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Adcock A.,50 Serra Mall | Rubin D.,Richard cas Center | Carlsson G.,Bldg
Computer Vision and Image Understanding | Year: 2014

In this paper we present a methodology of classifying hepatic (liver) lesions using multidimensional persistent homology, the matching metric (also called the bottleneck distance), and a support vector machine. We present our classification results on a dataset of 132 lesions that have been outlined and annotated by radiologists. We find that topological features are useful in the classification of hepatic lesions. We also find that two-dimensional persistent homology outperforms one-dimensional persistent homology in this application. © 2014 Elsevier Ltd. All rights reserved. Source

Trufanov V.D.,Peoples Friendship University of Russia | Kogan E.A.,Moscow State University | Yutskovskaya Y.A.,Bldg | Faizullina N.M.,Research Center for Obstetrics | Ivanov S.Y.,Nizhny Novgorod State Medical Academy
Sovremennye Tehnologii v Medicine | Year: 2016

The aim of investigation was to evaluate the efficiency of high frequency radio wave exposure (4.0 MHz) for the correction of age-related changes of facial skin by studying aspects of its regeneration, on the basis of morphological and immunohistochemical characteristics. Materials and Methods. The study consisted of two parts. The clinical part included an analysis of the results of high frequency radio wave facial rejuvenation (4.0 MHz) (5 procedures: on days 1, 30, 60, and months 6, 12). Immunohistochemical investigation was performed on repeated punch-biopsy specimens of the skin behind the ear, before the exposure, and at 30, 60, 180 and 360 days after a single exposure. Collagen of types 1 and 3, elastin, Ki-67, CD34, SMA, MMP2 and TIMP1 were identified. Results. It was found that the most evident morphological changes after high frequency radio wave exposure occurred in the deeper dermis layers and in the adjacent adipose tissue. Such remodeling of the extracellular matrix of the dermis causes an expansion of the deep dermis layers with the accumulation of collagen of types 1 and 3 with a greater proportional increase in favor of type 1. The key anti-ageing factor of radio wave exposure is considered to be the activation of neoangiogenesis in the dermis, which occurs gradually, reaching its maximum by month 12 after a single exposure. © 2016, Nizhny Novgorod State Medical Academy. All rights reserved. Source

Breinholt A.,Bldg | Thordarson F.O.,Bldg | Moller J.K.,Bldg | Grum M.,Kruger | And 2 more authors.
Environmetrics | Year: 2011

Generating flow forecasts with uncertainty limits from rain gauge inputs in sewer systems require simple models with identifiable parameters that can adequately describe the stochastic phenomena of the system. In this paper, a simple grey-box model is proposed that is attractive for both forecasting and control purposes. The grey-box model is based on stochastic differential equations and a key feature is the separation of the total noise into process and measurement noise. The grey-box approach is properly introduced and hypothesis regarding the noise terms are formulated. Three different hypotheses for the diffusion term are investigated and compared: one that assumes additive diffusion; one that assumes state proportional diffusion; and one that assumes state exponentiated diffusion. To implement the state dependent diffusion terms Itô's formula and the Lamperti transform are applied. It is shown that an additive diffusion noise term description leads to a violation of the physical constraints of the system, whereas a state dependent diffusion noise avoids this problem and should be favoured. It is also shown that a logarithmic transformation of the flow measurements secures positive lower flow prediction limits, because the observation noise is proportionally scaled with the modelled output. Finally it is concluded that a state proportional diffusion term best and adequately describes the one-step flow prediction uncertainty, and a proper description of the system noise is important for ascertaining the physical parameters in question. © 2011 John Wiley & Sons, Ltd. Source

German M.A.,Bldg | Zardouz S.,Bldg | Sina M.K.,Bldg | Ziai K.,Bldg | And 2 more authors.
Otology and Neurotology | Year: 2011

Objective: To evaluate the use of radiation by neurotologists practicing in the United States as a treatment modality for vestibular schwannomas (VSs). Study Design: Cross-sectional survey. Methods: We surveyed 302 members of the American Neurotology Society to assess the number of VS seen, the frequency with which radiation is used as a treatment modality, radiation training and experience, the impact of tumor size and patient age on treatment decisions, and radiation dose ultimately used by neurotologists. Results: Responses were received from 43% (132/302) of surveyed neurotologists; of the respondents, 42% (54/132) perform stereotactic radiation. Approximately 58% (30/54) of those use gamma knife, and 44% (24/54) use Cyberknife; 36.7% of VS patients seen by neurotologists received radiation. On average, 6 additional neurotologists per year begin treating VS with stereotactic radiation. Academic and private neurotologists showed significant differences (p < 0.05) between new VS patients per year, years in practice, and maximum tumor size recommended for radiation. The most common barrier to using radiation was prevention by a neurosurgical or radiation oncology service. Neurotologists use radiation to treat other cranial base tumors as well, most commonly glomus tumors or meningiomas, and 64% of respondents irradiate neurofibromatosis Type 2. Total radiation dose and fractionation were variable. Conclusion: Neurotologists are increasingly choosing to treat VS with stereotactic radiation. There seem to be significant differences between academic and private neurotologists' practice characteristics. Not all neurotologists strictly adhere to the consensus statement by the International RadioSurgery Association with regard to radiation dosing and tumor size limits. Copyright © 2011 Otology & Neurotology, Inc. Source

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