Particle Filtering Methods for Subcellular Motion Analysis

Advances in fluorescent probing and microscopic imaging technology have revolutionized biology in the past decade and have opened the door for studying subcellular dynamical processes. However, accurate and reproducible methods for processing and analyzing the images acquired for such studies are still lacking. Since manual image analysis is time consuming, potentially inaccurate, and poorly reproducible, many biologically highly relevant questions are either left unaddressed, or are answered with great uncertainty. The subject of this thesis is particle filtering methods and their application for multiple object tracking in different biological imaging applications. Particle filtering is a technique for implementing recursive Bayesian filtering by Monte Carlo sampling. A fundamental concept behind the Bayesian approach for performing inference is the possibility to encode the information about the imaging system, possible noise sources, and the system dynamics in terms of probability density functions. In this thesis, a set of novel PF based metho

Fuzzy-Logic Based Detection and Characterization of Junctions and Terminations in Fluorescence Microscopy Images of Neurons

Digital reconstruction of neuronal cell morphology is an important step toward understanding the functionality of neuronal networks. Neurons are tree-like structures whose description depends critically on the junctions and terminations, collectively called critical points, making the correct localization and identification of these points a crucial task in the reconstruction process. Here we present a fully automatic method for the integrated detection and characterization of both types of critical points in fluorescence microscopy images of neurons. In view of the majority of our current studies, which are based on cultured neurons, we describe and evaluate the method for application to two-dimensional (2D) images. The method relies on directional filtering and angular profile analysis to extract essential features about the main streamlines at any location in an image, and employs fuzzy logic with carefully designed rules to reason about the feature values in order to make well-informed decisions about the presence of a critical point and its type. Experiments on simulated as well as real images of neurons demonstrate the detection performance of our method. A comparison with the output of two existing neuron reconstruction methods reveals that our method achieves substantially higher detection rates and could provide beneficial information to the reconstruction process

Результати оцінки стійкості лінійних параметричних систем трьома методами

This paper  contains the comparison of results of the assessment of stability of linear parametric systems by three methods: frequency symbolic method, the method of slow amplitudes and the method based on Lyapunov's second method. The Assessment of stability  done for systems of second order  with periodically varying parameters.В роботе приведено сравнение результатов оценки устойчивости линейных параметрических систем тремя методами: частотным символьным методом, методом медленноменяющихся амплитуд и методом, основанном на втором методе Ляпунова. Оценка устойчивости проведена для систем второго порядка с периодически изменяющимися параметрамиУ роботі наведені порівняння результатів оцінки стійкості лінійних параметричних систем трьома методами: частотним символьним методом, методом повільних амплітуд та методом, основаним на другому методі Ляпунова. Оцінка стійкості проведена для систем другого порядку з періодично змінними параметрами

MRI imaging of vein of Galen malformations at Steve Biko Academic Hospital : a mini case series

No abstract available.http://www.journals.co.za/sama/m_sajr.htm

З'єднання зварюванням

Метою методичних вказівок «З’єднання зварюванням» є ознайомлен-ня зі способами нероз’ємних з’єднань, вивчення правил зображення та поз-начення швів з’єднань зварюванням на кресленні, набуття навиків виконан-ня, оформлення та читання креслень з’єднань зварюванням, які необхідні для вивчення загально-інженерних та спеціальних технічних дисциплін.Вступ...3 1.Загальні відомості....4 2.Класифікація з’єднаньзварюванням...4 3.Умовне зображення і позначення швів з’єднань, які зварюють....7 4.Спрощене позначення швів з’єднаньякі зварюють...15 5.Оформлення креслень з’єднань зварюванням...23 6.Вказівки до виконання графічних робіт та індивідуальні завдання...24 7.Додаток А...27 8.Додаток Б...28 9.Додаток В...29 10.Використана література...4

Marker-Less Stage Drift Correction in Super-Resolution Microscopy Using the Single-Cluster PHD Filter

Fluorescence microscopy is a technique which allows the imaging of cellular and intracellular dynamics through the activation of fluorescent molecules attached to them. It is a very important technique because it can be used to analyze the behavior of intracellular processes in vivo in contrast to methods like electron microscopy. There are several challenges related to the extraction of meaningful information from images acquired from optical microscopes due to the low contrast between objects and background and the fact that point-like objects are observed as blurred spots due to the diffraction limit of the optical system. Another consideration is that for the study of intracellular dynamics, multiple particles must be tracked at the same time, which is a challenging task due to problems such as the presence of false positives and missed detections in the acquired data. Additionally, the objective of the microscope is not completely static with respect to the cover slip due to mechanical vibrations or thermal expansions which introduces bias in the measurements. In this paper, a Bayesian approach is used to simultaneously track the locations of objects with different motion behaviors and the stage drift using image data obtained from fluorescence microscopy experiments. Namely, detections are extracted from the acquired frames using image processing techniques, and then these detections are used to accurately estimate the particle positions and simultaneously correct the drift introduced by the motion of the sample stage. A single cluster Probability Hypothesis Density (PHD) filter with object classification is used for the estimation of the multiple target state assuming different motion behaviors. The detection and tracking methods are tested and their performance is evaluated on both simulated and real data

Bestemmingsplan buitengebied 2010, gemeente Cuijk, Toetsingsadvies over het milieueffectrapport

De Gemeente Cuijk wil een nieuw bestemmingsplan buitengebied vaststellen. Hierin worden groei van veehouderijen en nieuwe recreatieve ontwikkelingen mogelijk gemaakt. Omdat dit bestemmingsplan kaderstellend is voor toekomstige m.e.r.-(beoordelings)plichtige activiteiten (intensieve veehouderij) en omdat mogelijk een passende beoordeling volgens de Natuurbeschermingswet 1998 moet worden opgesteld, is voor dit bestemmingsplan een planm. e.r.-procedure doorlopen. Bevoegd gezag voor deze m.e.r.-procedure is de gemeenteraad van Cuijk

Structural, transport and microwave properties of 123/sapphire films: Thickness effect

The effect of thickness and growth conditions on the structure and microwave properties has been investigated for the 123/sapphire films. It has been shown that in the conditions of epitaxial growth the Al atoms do not diffuse from substrate into the film and the films with thickness up to 100 nm exhibit the excellent direct current (DC) properties. The increase of thickness of GdBaCuO films causes the formation of extended line-mesh defects and the increase of the surface resistance (R(sub S)). The low value of surface resistance R(sub S)(75 GHz, 77K) = 20 mOhm has been obtained for the two layer YBaCuO/CdBaCuO/sapphire films

The opposite association of HRAS and KRAS mutations with clinical variables of bladder cancer

HRAS, KRAS and NRAS gene products belong to the superfamily of small GTPases. These proteins regulate cellular response to extracellular stimuli by means of activation of different signaling pathways. Although the role of RAS gene mutations in the pathogenesis of various human cancers has been established, the clinical significance of these molecular alterations in bladder cancer remains unclear. The aim of this study was to determine the frequency and spectrum of HRAS, KRAS and NRAS mutations, to analyze their relationships with clinicopathological variables and to determine the prognostic value of these alterations in terms of recurrence, progression and mortality, in a prospective cohort of 249 bladder cancer patients. The frequency of RAS mutations detected by the SNaPshot method, was found to be 11.2 %, of which HRAS mutations accounted for 64.3 %, KRAS, for 28.6 % and NRAS, for 7.1 %. We failed to find any correlation between all RAS mutations and pathomorphological characteristics. However, when analyzed separately, HRAS and KRAS mutations were for the first time shown to be associated with the opposite clinical parameters of bladder cancer: HRAS mutations were significantly associated with low-stage low-grade papillary tumors of a small size (р < 0.05), whereas KRAS mutations were associated with non-papillary urothelial carcinomas and the presence of metastasis (р < 0.05). Analysis of the prognostic value of molecular alterations revealed an association of KRAS mutations with decreased cancer-specific survival in both the whole group of patients and the subgroup with non-muscle invasive disease. The data obtained suggest that HRAS and KRAS gene mutations may characterize alternative pathways of bladder cancer pathogenesis: HRAS mutations indicating benign and KRAS mutations, aggressive disease course