Prostate cancer recognition in ultrasound images

Our purpose is to aid medical doctors in prostate cancer detection via computer automated analysis of prostatic ultrasound imagery. Absorption of ultrasound signals is different in cancerous areas than in non-cancerous areas. The energy of the signal, the continuity of the signal, the autocorrelation function and frequency domain properties of prostatic ultrasound images are different in normal tissue than in cancerous tissue; This thesis presents an algorithm for automated cancer recognition in prostatic ultrasound imagery. Statistical and morphological based models are employed to classify regions of ultrasound imagery as either cancerous or non-cancerous. Application of our algorithm onto a limited set of cancerous and non-cancerous ultrasound images shows that our method has the ability to recognize cancer in cancerous ultrasound images. Misclassification occurs when cancerous tissue is classified as non-cancerous and noncancerous tissue is classified as cancerous. Occurrences of misclassification have been observed and investigated. (Abstract shortened by UMI.)

Реконструкция трехмерных моделей анатомических объектов на основе анализа биомедицинских изображений

Медицинский анализ изображений, моделирование и технология печати 3D обеспечивает решение для медицинского исследования и конкретный путь для диагностики и анализа проблем со здоровьем человека. Практически обеспечивает новый метод обработки изображений с помощью инструмента компьютерного программного обеспечения, включая статистический анализ и алгоритм. Этот метод был разделен на две основные категории - моделирование изображений и обработка изображений. В этом докладе я описываю процедуру, как использовать данные DICOM, которые можно преобразовать в 3D печатные модели. В первой категории моделирования мы можем сделать модель и после этого 3D-печать через указанные программные средства.Medical image analysis, 3D modeling & printing technology provide a solution for medical research and a specific path to diagnose & analyze human health issues. The 3D Biomedical images of human body through CT scanning.Practically image analysis provides a new technique of image processing through computer software tool including statistical analysis and algorithm. It has been divided into two main categories as image modeling and image processing. In this report, I am describing the procedure that how to use the DICOM data can transform into 3D printed models. In the first category of modeling, we are able to make a model and after that 3D printing through the specified software tool

X-Ray imaging applied to the characterization of polymer foam's cellular structure and its evolution

Las espumas poliméricas son materiales celulares que poseen una fase sólida continua y otra gaseosa bien discontinua (celda cerrada) o continua (celda abierta). Habitualmente estas estructuras se describen mediante parámetros macroscópicos como la densidad relativa y otros microscópicos como el tamaño de celda o la densidad de celdas. Además, estos materiales poseen características peculiares como anisotropía, orientación de los poros y tortuosidad que les proporcionan propiedades físicas singulares. Convencionalmente el estudio de las espumas poliméricas se realiza mediante el análisis de la estructura celular final obtenida. Ello se debe principalmente a que es complicado detener el proceso de expansión una vez se ha iniciado. Debido a esto los estadios intermedios durante los procesos de espumado no son accesibles, es decir, no se obtiene información acerca de los mecanismos que generan la estructura final. Estos mecanismos físico-químicos fundamentales que gobiernan la generación y evolución de la estructura celular durante el espumado son la nucleación y el crecimiento. Por el contrario, existen otros mecanismos que son responsables de la degeneración de la estructura celular son el drenaje, la coalescencia y el coarsening. Los inconvenientes que existen para abordar el estudio de estos mecanismos durante el proceso de espumado, junto con las peculiaridades de estos sistemas hacen que las técnicas de imagen mediante rayos X sean una herramienta extraordinaria para el estudio in-situ de la evolución de la estructura celular y los mecanismos de espumado. Además, de manera complementaria, la imagen mediante rayos X permite la obtención de tomogramas para el estudio de la estructura celular en el estado final. Incluso es posible llegar más lejos gracias a los últimos desarrollos en tomografía rápida. Esta técnica es capaz de estudiar en 3D la evolución de la estructura celular en el tiempo. Uno de los requisitos esenciales para el estudio de las espumas poliméricas mediante la imagen con rayos X y que condiciona su aplicabilidad es la correcta selección de los componentes y el diseño del equipo de imagen. Esto se debe principalmente a características intrínsecas a las espumas poliméricas: baja absorción de los rayos X, espesores reducidos, estructura de celdas en el rango micrométrico, rápida evolución durante su fabricación y otras peculiaridades morfológicas de su estructura.Departamento de Física de la Materia Condensada, Cristalografía y Minerealogí

Determination of the actual morphology of core-shell nanoparticles by advanced X-ray analytical techniques: A necessity for targeted and safe nanotechnology

Obwohl wir sie oft nicht bewusst wahrnehmen, sind Nanopartikel heutzutage in den meisten Bereichen unseres Alltags präsent, unter anderem in Lebensmitteln und ihren Verpackungen, Medizin, Medikamenten, Kosmetik, Pigmenten und in elektronischen Geräten wie Computermonitoren. Ein Großteil dieser Partikel weist, beabsichtigt oder unbeabsichtigt, eine Kern-Schale Morphologie auf. Einfachheitshalber wird diese Morphologie eines Kern-Schale-Nanopartikels (CSNP) oft als ideal angenommen, d.h. als ein sphärischer Kern, der komplett von einer Schale homogener Dicke bedeckt ist, mit einer scharfen Grenzfläche zwischen Kern- und Schalenmaterial. Außerdem wird vielfach auch davon ausgegangen, alle Partikel der Probe hätten gleiche Schalendicken. Tatsächlich weichen die meisten realen CSNPs in verschiedenster Weise von diesem Idealmodell ab, mit oft drastischen Auswirkungen darauf, wie gut sie ihre Aufgabe in einer bestimmten Anwendung erfüllen. Das Thema dieser kumulativen Doktorarbeit ist die exakte Charakterisierung der wirklichen Morphologie von CSNPs mit modernen Röntgen-basierten Methoden, konkret Röntgen-Photoelektronen-Spektroskopie (XPS) und Raster-Transmissions-Röntgen-Mikroskopie (STXM). Der Fokus liegt insbesondere auf CSNPs, die von einer idealen Kern-Schale-Morphologie abweichen. Aufgrund der enormen Vielfalt an CSNPs, die sich in Material, Zusammensetzung und Form unterscheiden, kann eine Messmethode nicht völlig unverändert von einer Probe auf eine andere übertragen werden. Nichtsdestotrotz, da die als Teil dieser Doktorarbeit präsentierten Artikel eine deutlich ausführlichere Beschreibung der Experimente enthalten als vergleichbare Publikationen, stellen sie eine wichtige Anleitung für andere Wissenschaftler dafür dar, wie aussagekräftige Informationen über CSNPs durch Oberflächenanalytik erhalten werden können.Even though we often do not knowingly recognize them, nanoparticles are present these days in most areas of our daily life, including food and its packaging, medicine, pharmaceuticals, cosmetics, pigments as well as electronic products, such as computer screens. The majority of these particles exhibits a core-shell morphology either intendedly or unintendedly. For the purpose of practicability, this core-shell nanoparticle (CSNP) morphology is often assumed to be ideal, namely a spherical core fully encapsulated by a shell of homogeneous thickness with a sharp interface between core and shell material. It is furthermore widely presumed that all nanoparticles in the sample possess the same shell thickness. As a matter of fact, most real CSNPs deviate in several ways from this ideal model with quite often severe impact on how efficiently they perform in a specific application. The topic of this cumulative PhD thesis is the accurate characterization of the actual morphology of CSNPs by advanced X-ray analytical techniques, namely X-ray photoelectron spectroscopy (XPS) and scanning transmission X-ray microscopy (STXM). A special focus is on CSNPs which deviate from an ideal core-shell morphology. Due to the vast diversity of nanoparticles differing in material, composition and shape, a measurement procedure cannot unalteredly be transferred from one sample to another. Nevertheless, because the articles in this thesis present a greater depth of reporting on the experiments than comparable publications, they constitute an important guidance for other scientists on how to obtain meaningful information about CSNPs from surface analysis

Targeted optimization of chromatographic columns based on 3D analysis of packing microstructure

The preparation, structure, and performance of functional materials porous are strongly interrelated. Hence, a detailed analysis of the pore structure of a functional porous material in combination with a detailed characterisation of its performance can provide an understanding of the influence of individual parameters during preparation and thus identify structural limitations to an improved utilization. The obtained results can be used to tune the preparation towards a better pore structure suited for the targeted application. This work focuses on packings of silica-based particles for highly efficient chromatographic separations. The prepared packings combine an interparticle macropore space for fast flow-based transport with an intraparticle mesopore space providing high surface areas for molecule-surface interactions. Such packed columns have a wide field of application, not only in highly efficient separations, but also for catalysis, and (energy) storage However, the focus here is on separations in liquid chromatography. In Chapter 1, the influence of the slurry concentration on separation efficiency and bed structure was investigated for capillary columns (75 µm inner diameter, 30 cm length) packed with 1.3 µm bridged-ethyl hybrid (BEH) fully porous silica particles. The slurry concentration was varied from 5 to 50 mg/mL while every other packing parameter was kept constant. Chromatographic characterisation with hydroquinone as weakly retained analyte revealed highly efficient separations (reduced plate heights as low as 1.5) at an optimal intermediate slurry concentration of 20 mg/mL for this specific set of packing parameters. Confocal laser scanning microscopy (CLSM) was utilized to conduct a three-dimensional reconstruction and to carry out a detailed morphological analysis of the column with the best performance, a column packed with a slurry concentration below the optimum, and one packed above the optimum. Two counteracting effects were revealed: Radial heterogeneities limit the separation efficiency for columns packed at low slurry concentrations. With an increase in slurry concentration, these radial effects get supressed but the number and size of large voids with a diameter similar to the mean particle diameter increase significantly. Interestingly, the reconstructions also revealed high external bed porosities between 0.47 and 0.50 which are higher than expected with respect to the random loose packing limit reported for frictional, cohesionless particles. However, no signs of bed instability could be observed demonstrating the significant impact of interparticle forces for particles as small as 1.3 µm. In Chapter 2, the investigation of the optimal slurry concentration was expanded by analysing the effects for a different particle size to obtain a more general picture. A similar set of capillary columns (75 µm inner diameter, 45 cm length) was packed with 1.9 µm BEH particles at eleven different slurry concentrations between 5 and 200 mg/mL including additional tests for reproducibility at selected concentrations and the observation of bed formation using optical microscopy. While comparable reduced plate heights were achieved, the observed optimum of 140-160 mg/mL to pack highly efficient columns reproducibly differed significantly from the 20 mg/mL for the 1.3 µm particles identified in Chapter 1. This can be explained by the difference in the particle diameter as interparticle forces and particle aggregation become more dominant at still smaller diameters. CLSM-based reconstructions revealed similar trends in the bed structures as seen in Chapter 1. At low concentrations, pronounced ordered particle layers in the direct vicinity of the column wall, local bed densification near the column wall, and particle size-segregation limit the achieved separation efficiency. The peculiarity of the first effect is continuously decreasing with an increase in the slurry concentration even beyond the optimum while the latter two effects are already supressed at the optimal slurry concentration. On the other hand, the number and size of large voids increase with an increase in the utilized slurry concentration as already seen in Chapter 1. The videos acquired during column packing provided very helpful insights into bed formation mechanisms and thus delivered possible explanations for these structural features. At 10 mg/mL, particles arrive individually at the bed front allowing individual settlement and rearrangement on the arrival of following particles what allows a discrimination of particles according to their individual properties. The picture looks completely different for 100 mg/mL as example for higher concentrated slurries. Here, particles tend to aggregate during packing and arrive in large batches. This prevents discrimination of individual particles but significantly reduces the chances for rearrangement and is thus prone to the conservation of defects formed between the border of the arriving batches of particles and the front of the bed. Chapter 3 is based on the results obtained during the work presented in Chapters 1 and 2. The combination of high slurry concentration and ultrasound was already proposed there as chance to keep transcolumn heterogeneities as low as possible while preventing the formation of large voids. To test this hypothesis, two sets, each consisting of three capillary columns (75 µm inner diameter, 100 cm length) were packed with 1.9 µm BEH particles at a slurry concentration of 200 mg/mL; one set under application of ultrasound during packing, the other one without. All three columns, which underwent sonication, showed significantly better performance than each of the other columns. The obtained reduced minimum plate height for a weakly retained analyte was even lower than the already impressive value of 1.5 for columns packed at a slurry concentration optimal for packing without sonication and reached values close to unity over a length of 1 m for the best-performing column. The achieved theoretical plate counts of ~500,000 demonstrate a unique potential for highly efficient separations of extremely complex samples. In Chapter 4, the focus is shifted from capillary columns to the more common analytical format. CLSM could not be applied here as the steel columns are not transparent and extrusion of the bed is not possible without losing either stability or optical transparency. Thus, an imaging and reconstruction procedure based on focused ion beam scanning electron microscopy was developed using a commercial narrow-bore analytical column (2.1 mm inner diameter, 50 mm length) packed with 1.7 µm BEH particles. The packing was embedded with poly(divinylbenzene) prior to extrusion from the steel column in order to conserve the bed structure. Two image stacks were acquired and reconstructed at characteristic positions within the bed: one in the central section of the column along the flow direction to obtain the bulk properties of the bed and one from the column wall towards the column centre to investigate and quantify the influence of the geometrical wall effect and the second wall effect. To investigate the effect of the microstructure in the wall region on local flow through the bed, a radially resolved flow profile was obtained by lattice-Boltzmann simulations. For this column, the region affected by wall effects spanned over approximately 62 particle diameters showing a decrease in the local mean porosity by up to 10% and an increase in the local mean particle diameter by up to 3% with respect to the bulk region inducing a decrease of the local flow velocity by up to 23%. Furthermore, four more ordered layers of particles were formed directly at the hard column wall due to the geometrical wall effect leading to local velocity fluctuations by up to a factor of three. These quantified structural features are in excellent agreement with previous reports about macroscopic characterisations of the wall effects by optical or chromatographic measurements

Novel methods for subcellular in vivo imaging of the cornea with the Rostock Cornea Module 2.0

The Rostock Cornea Module transforms a confocal laser scanning ophthalmoscope into a corneal confocal laser scanning microscope. In this thesis, an improved version, the Rostock Cornea Module 2.0, and its achieved results were demonstrated. These include a concave contact cap design to attenuate eye movements to improve 3D volume reconstruction, an oscillating focal plane to improve mosaicking of the subbasal nerve plexus, the integration of simultaneous optical coherence tomography, multiwavelength corneal imaging, the clinical usage, and the automated morphological characterization

Liver Biopsy

Liver biopsy is recommended as the gold standard method to determine diagnosis, fibrosis staging, prognosis and therapeutic indications in patients with chronic liver disease. However, liver biopsy is an invasive procedure with a risk of complications which can be serious. This book provides the management of the complications in liver biopsy. Additionally, this book provides also the references for the new technology of liver biopsy including the non-invasive elastography, imaging methods and blood panels which could be the alternatives to liver biopsy. The non-invasive methods, especially the elastography, which is the new procedure in hot topics, which were frequently reported in these years. In this book, the professionals of elastography show the mechanism, availability and how to use this technology in a clinical field of elastography. The comprehension of elastography could be a great help for better dealing and for understanding of liver biopsy

Von Staub zu Planeten: Staub Aggregation im post-fraktalen Wachstumsregime

The formation of planets and especially the first aggregation phase from (sub-)micrometer-sized dust grains into larger bodies is not understood. In this work, experiments are presented to study this growth phase. Based on new as well as previously published experiments, a model is then constructed that makes an outcome prediction for every possible dust aggregate collision, i.e. in terms of sticking, bouncing, and fragmentation. This model is necessary to understand the full evolution of dust aggregates in a protoplanetary disk environment, and the result is that the dust readily aggregates into centimeter-sized pebbles until bouncing collisions inhibit the further growth. Although the ultimate growth to even larger bodies can actually not be explained, this study presents the first conclusive picture for the growth from micrometer-sized dust grains to centimeter-sized, porous dust aggregates.Die Entstehung von Planeten und im Besonderen die erste Aggregations-Phase von (Sub-)Mikrometer großen Staub Teilchen in größere Körper ist in weiten Teilen nicht verstanden. In dieser Arbeit werden Experimente präsentiert, um diese erste Wachstumsphase zu erforschen. Basierend auf neuen sowie bereits publizierten Experimenten wird dann ein Modell konstruiert, welches eine Vorhersage über das Ergebnis jeder möglichen Staubagglomerat-Kollision macht, d.h. ob diese zu Haftung, Abprallen oder Fragmentation führt. Dieses Modell ist nötig um die Entwicklung von Staub in einer Protoplanetaren Scheibe zu verstehen zu können, und das Ergebnis ist, dass der Staub bis zu Zentimeter Größe agglomeriert und das weitere Wachstum dann durch abprallende Stöße gehemmt wird. Obwohl das weitere Wachstum zu größeren Körpern letztlich nicht geklärt werden kann, wird in dieser Arbeit erstmals ein schlüssiger Weg für das Wachstum von Mikrometer großen Staubkörnern zu Zentimeter großen, porösen Staubaggregaten dargelegt