bluuebunny/crossref_metadata_2025 huggingface dataset:
AUTOMATED CONSTRUCTION OF 3D STATISTICAL SHAPE MODELS
Authors: Vrtovec Tomaž , Tomaževič Dejan , Likar Boštjan , Travnik Ludvik , Pernuš Franjo
Published: July 2011

Automated segmentation of medical images is a difficult task because of the complexity of anatomic structures, inter-patient variability, and imperfect image acquisition. Prior knowledge, in the form of pointbased statistical shape models (point distribution models) of a structure of interest can greatly assist segmentation to robustly find the structure in a patient's image. Point distribution models are obtained through sets of corresponding landmarks lying on surfaces of training structures. The key to the automated construction of a three-dimensional (3D) statistical shape model is the identification of corresponding landmarks on training shapes, which is a challenging task. This paper presents a novel method for automated construction of 3D point distribution models. Corresponding surface points are obtained by two main steps: 1) volumes of interest (VOI), each containing one training structure, are manually defined, a reference structure is manually extracted from one training VOI and its surface is established and represented by a set of (reference) points, 2) reference landmarks are propagated to other training VOIs by transformations that are obtained by hierarchical elastic registration between the reference and each of the remaining training VOIs. We illustrate our approach using computed tomography data of the lumbar vertebra.
A PRELIMARY APPROACH FOR THE AUTOMATED RECOGNITION OF MALIGNANT MELANOMA
Authors: Zagrouba Ezzeddine , Barhoumi Walid
Published: July 2011

In this work, we are motivated by the desire to classify skin lesions as malignants or benigns from color photographic slides of the lesions. Thus, we use color images of skin lesions, image processing techniques and artificial neural network classifier to distinguish melanoma from benign pigmented lesions. As the first step of the data set analysis, a preprocessing sequence is implemented to remove noise and undesired structures from the color image. Second, an automated segmentation approach localizes suspicious lesion regions by region growing after a preliminary step based on fuzzy sets. Then, we rely on quantitative image analysis to measure a series of candidate attributes hoped to contain enough information to differentiate melanomas from benign lesions. At last, the selected features are supplied to an artificial neural network for classification of tumor lesion as malignant or benign. For a preliminary balanced training/testing set, our approach is able to obtain 79.1% of correct classification of malignant and benign lesions on real skin lesion images.
THE EFFECT OF RARE EARTH ELEMENTS ON Cr PRECIPITATIONS IN A Cu-0.8WT%Cr ALLOY
Authors: Shuai Gewang , Zhang Meng , Yan Yongli
Published: July 2011

The microstructural evolution of Cu-based alloys during aging was studied using a quantitative metallographic method. Samples were cut from ingots of Cu-0.8wt%Cr and Cu-0.8wt%Cr-RE alloys. These were solution treated at 1000 ºC for 1.5h and subsequently quenched in water, then separately aged at 480 ºC for different durations. The microstructures were observed by optical microscope, and the characteristic geometric parameters of precipitated Cr phase, including volume fraction VV, face density NA, mean diameter and roundness, were measured. These data provided more details about the process of aging. The results showed that precipitation of Cr phase occurred in the form of particles during aging. Rare earth elements promoted the precipitation of Cr phase and dispersed Cr particles. The phenomenon of overaging came earlier in Cu-Cr-RE than in Cu-Cr. In the present work, the optimal aging time at 480 ºC was 2 hrs for the Cu-0.8wt%Cr-RE alloy and 3 hours for the Cu-0.8wt%Cr alloy.
CELL SEPARATION AND GENE EXPRESSION ANALYSIS IN A TUMOR-STROMA INTERACTION MODEL
Authors: Dahse Regine , Kosmehl Hartwig
Published: July 2011

A novel technique for co-culturing and separating fibroblasts and carcinoma cells in a 2-D model of tumorstroma interaction is presented. The methodology is based on cell co-cultivation on an 1.35 μm thin membrane followed by rapid immunostaining and microdissection of the different cell compartments using a laser microdissection system (P.A.L.M. Microlaser Technologies AG, Germany). For identifying the tumor cell compartment, immunolabeling for a marker that is expressed only in epithelial tumor cells is performed. The RNA quality from the microdissected co-cultured cells was successfully proved by RT-PCR for a housekeeping gene transcript and for the laminin gamma 2 chain gene transcript used before in the tumor cell immunostaining. Laminin cDNA was amplificable only in tumor cells and not in the co-cultivated fibroblasts indicating no cell-cross-contamination during microdissection. Microdissected tumor and stroma cells from the presented membrane based co-culture model can be used for gene expression profiling and DNA based analysis in the investigation of tumor-stroma interactions.
SERIAL SECTIONS THROUGH A CONTINUOUS FIBER-REINFORCED POLYMER COMPOSITE
Authors: Bizet Laurent , Bréard Joël , Bouquet Guy , Jernot Jean-Paul , Gomina Moussa
Published: July 2011

The microstructure of a unidirectional glass-fiber composite material is described seeking especially for the influence of the stitching perpendicular to the reinforcement. Serial cuts are performed through the composite and the microstructure is quantified using global parameters and linear morphological analysis. A key result is that the stitching induces variations in fibers spacing within the yarns and in the matrix volume between the yarns. This can affect noticeably the flow of the resin during the manufacturing process and also the mechanical properties of the composite.
A TIME-OPTIMAL ALGORITHM FOR THE ESTIMATION OF CONTACT DISTRIBUTION FUNCTIONS OF RANDOM SETS
Authors: Mayer Johannes
Published: July 2011

This paper presents a linear-time and therefore time-optimal algorithm for the estimation of distance distribution functions and contact distribution functions of random sets. The distance distribution function is the area fraction of a dilated set, where this function depends on the size of the structuring element used for the dilation. Furthermore, contact distribution functions are related to distance distribution functions. Minussampling estimators are used for the estimation.
SPATIAL EXTRAPOLATION OF ANISOTROPIC ROAD TRAFFIC DATA
Authors: Braxmeier Hans , Schmidt Volker , Spodarev Evgueni
Published: July 2011

A method of spatial extrapolation of traffic data is proposed. The traffic data is given by GPS signals over downtown Berlin sent by approximately 300 taxis. To reconstruct the traffic situation at a given time spatially, i.e., in the form of traffic maps, kriging with moving neighborhood based on residuals is used. Due to significant anisotropy in directed traffic data, the classical kriging has to be modified in order to include additional information. To verify the extrapolation results, test examples on the basis of a well-known model of stochastic geometry, the Boolean random function are considered.
MODELLING A FOOD MICROSTRUCTURE BY RANDOM SETS
Authors: Bron Frederic , Jeulin Dominique
Published: July 2011

Starting from scanning electron microscope images of some food products, we generate binary images of composite materials. After measuring the covariance and the probability for segments and for squares to be included in the dominant component, we develop a modelling of the microstructure from random sets obtained by thresholding Gaussian random functions. The covariance function of the underlying Gaussian random function is estimated from the experimental covariance of the food products. The validity of the model is checked by comparison of the probability curves for segments and for squares, measured on simulated and on initial images. The approach enables us to generate 3D realisations of the microstructure.
IMAGE REGISTRATION BASED ON MAXIMIZATION OF GRADIENT CODE MUTUAL INFORMATION
Authors: Wang Xiaoxiang , Tian Jie
Published: July 2011

Herein one proposes a mutual information-based registration method using pixel gradient information rather than pixel intensity information. Special care is paid to finding the global maximum of the registration function. In particular, one uses simulated annealing method speeded up by including a statistical analysis to reduce the next search space across the cooling schedule. An additional speed up is obtained by combining this numerical strategy with hill-climbing method. Experimental results obtained on a limited database of biological images illustrate that the proposed method for image registration is relatively fast, and performs well as the overlap between the floating and reference images is decreased and/or the image resolution is coarsened.
GAUSSIAN RADIAL GROWTH
Authors: Jónsdóttir Kristjana Ỷr , Jensen Eva B Vedel
Published: July 2011

The growth of planar and spatial objects is often modelled using one-dimensional size parameters, e.g., volume, area or average width. We take a more detailed approach and model how the boundary of a growing object expands in time. We mainly consider star-shaped planar objects. The model can be regarded as a dynamic deformable template model. The limiting shape of the object may be circular but this is only one possibility among a range of limiting shapes. An application to tumour growth is presented. A 3D version of the model is presented and an extension of the model, involving time series, is briefly touched upon.
DECIPHERING THE FINEST IMPRINT OF GLACIAL EROSION: OBJECTIVE ANALYSIS OF STRIAE PATTERNS ON BEDROCK
Authors: Stroeven Piet , Stroeven Arjen Peter , Hu Jing , Chermant Jean-Louis , Coster Michel
Published: July 2011

The aim of this study is to compare the efficiency of different mathematical and statistical geometrical methods applied to characterise the orientation distribution of striae on bedrock for deciphering the finest imprint of glacial erosion. The involved methods include automatic image analysis techniques of Fast Fourier Transform (FFT), and the experimental investigations by means of Saltikov's directed secants analysis (rose of intersection densities), applied to digital and analogue images of the striae pattern, respectively. In addition, the experimental data were compared with the modelling results made on the basis of Underwood's concept of linear systems in a plane. The experimental and modelling approaches in the framework of stereology yield consistent results. These results reveal that stereological methods allow a reliable and efficient delineation of different families of glacial striae from a complex record imprinted in bedrock.
SPATIALLY ADAPTIVE MORPHOLOGICAL IMAGE FILTERING USING INTRINSIC STRUCTURING ELEMENTS
Authors: Debayle Johan , Pinoli Jean-Charles
Published: July 2011

This paper deals with spatially adaptive morphological filtering, extending the theory of mathematical morphology to the paradigm of adaptive neighborhood. The basic idea in this approach is to substitute the extrinsically-defined, fixed-shape, fixed-size structuring elements generally used by morphological operators, by intrinsically-defined, variable-shape, variable-size structuring elements. These last so-called intrinsic structuring elements fit to the local features of the image, with respect to a selected analyzing criterion such as luminance, contrast, thickness, curvature or orientation. The resulting spatially-variant morphological operators perform efficient image processing, without any a priori knowledge of the studied image and some of which satisfy multiscale properties. Moreover, in a lot of practical cases, the elementary adaptive morphological operators are connected, which is topologically relevant. The proposed approach is practically illustrated in several application examples, such as morphological multiscale decomposition, morphological hierarchical segmentation and boundary detection.
QUANTIFICATION OF ANGIOGENESIS IN THE CHICKEN CHORIOALLANTOIC MEMBRANE (CAM)
Authors: Blacher Silvia , Devy Laetitia , Hlushchuk Ruslan , Larger Etienne , Lamandé Noel , Burri Peter , Corvol Pierre , Djonov Valentin , Foidart Jean-Michel , Noël Agnes
Published: July 2011

The chick chorioallantoic membrane (CAM) provides a suitable in vivo model to study angiogenesis and evaluate several pro- and anti-angiogenic factors and compounds. In the present work, new developments in image analysis are used to quantify CAM angiogenic response from optical microscopic observations, covering all vascular components, from the large supplying and feeding vessels down to the capillary plexus. To validate our methodology angiogenesis is quantified during two phases of CAM development (day 7 and 13) and after treatment with an antiangiogenic modulator of the angiogenesis. Our morphometric analysis emphasizes that an accurate quantification of the CAM vasculature needs to be performed at various scales.
FIRST USE OF STEREOLOGY TO QUANTIFY THE SURVIVAL OF FAT AUTOGRAFTS
Authors: Cuéllar Eduardo Serna , Solís Luis Santamaría
Published: July 2011

It is not usual to perform quantitative analyses on surgical materials. Rather, they are evaluated clinically, through qualitative methods, and if quantitation is done, it is on a 2-dimensional basis. In this study, the long-term survival of fat autografts (FAG) in 40 subjects with facial soft tissue defects is quantified. An adipose tissue preparation from the abdomen obtained through liposuction and centrifugation is injected subcutaneously. Approximately 14 months later, the treated area is biopsied. Extensive computer-based histological analyses were performed using the stereological method in order to directly obtain three parameters: volume fraction of adipocytes in the fat tissue (VV), density (number per volume) of adipocytes in the fat tissue (NV), and the mean cell volume of adipocytes (VA) in each tissue sample. A set of equations based on these three quantitative parameters is produced for evaluation of the volumetric survival fraction (VSF) of FAG. The presented data evidenced a 66% survival fraction at the 14-month follow-up. In routine practice, it would be sufficient to perform this volumetric analysis on the injected and biopsied fat samples to know what fraction of the FAG has survived. This is an objective method for quantifying FAG survival and will allow a standardized comparison between different research series and authors.
ADAPTIVE SKIN DETECTION UNDER UNCONSTRAINED LIGHTING CONDITIONS USING A BIGAUSSIAN MODEL AND ILLUMINATION ESTIMATION
Authors: Zheng Jian-Hua , Hao Chong-Yang , Fan Yang-Yu , Zang Xian-Yong
Published: July 2011

An algorithm is proposed to improve the performance of skin detection algorithms under poor illumination conditions. A hybrid skin detection model is addressed to solve these problems by combining two Gaussian models of skin under normal conditions and bright illumination. According to the distribution of the combined models, the algorithm automatically evaluates the skin segmentation result of an adaptive threshold algorithm based on a Gaussian model by estimating the illumination conditions of image. If the estimation result shows that the illumination condition is very different from the normal one, the skin color of the original image needs compensation, and then the algorithm feeds the compensated image back to the Gaussian model for finer skin detection. The experimental results show that our algorithm can cope with a complex illumination change and greatly improve skin classification performance under inferior illumination conditions.
AUTOMATIC ESTIMATION OF SIZE PARAMETERS USING VERIFIED COMPUTERIZED STEREOANALYSIS
Authors: Mouton Peter R , Durgavich Joel , Ingram Donald K
Published: July 2011

State-of-the-art computerized stereology systems combine high-resolution video microscopy and hardwaresoftware integration with stereological methods to assist users in quantifying multidimensional parameters of importance to biomedical research, including volume, surface area, length, number, their variation and spatial distribution. The requirement for constant interactions between a trained, non-expert user and the targeted features of interest currently limits the throughput efficiency of these systems. To address this issue we developed a novel approach for automatic stereological analysis of 2-D images, Verified Computerized Stereoanalysis (VCS). The VCS approach minimizes the need for user interactions with high contrast [high signal-to-noise ratio (S:N)] biological objects of interest. Performance testing of the VCS approach confirmed dramatic increases in the efficiency of total object volume (size) estimation, without a loss of accuracy or precision compared to conventional computerized stereology. The broad application of high efficiency VCS to high-contrast biological objects on tissue sections could reduce labor costs, enhance hypothesis testing, and accelerate the progress of biomedical research focused on improvements in health and the management of disease.
OPTIMAL RESOLUTION FOR AUTOMATIC QUANTIFICATION OF BLOOD VESSELS ON DIGITIZED IMAGES OF THE WHOLE CANCER SECTION
Authors: Françoise Ronan , Michels Jean-Jacques , Plancoulaine Benoît , Herlin Paulette
Published: July 2011

Discrepancies concerning the prognostic significance of cancer vascularization can be partly explained by biases due to quantification protocols. We recently recommended a swift, inexpensive and automatic analysis of 2,700 dpi slide scanner images of the whole immunostained sections. Another team, proposed, quite at the same time, to work at 4,000 dpi. The aim of the present paper is to check if information contained in images scanned at 2,700 and 4,000 dpi are relevant and equivalent, when compared to the low magnification of the microscope, in order to propose the best compromise between precision and time expense. To evaluate precisely the amount of information gained or lost according to the resolution used, we compared the number and size of blood vessel profiles, manually detected, on twenty one Hodgkin lymphoma acquired with a scanner (2,700 and 4,000 dpi) and with a microscope (16,000 dpi). Results obtained at 4,000 dpi were equivalent to the estimation performed at microscopical level either by a biologist or a pathologist, while tiny vessels were lost at 2,700 dpi. Scanning whole histological sections at 4,000 dpi provides a relevant method for evaluating tumour vascularization, which can be easily automated and standardized.
A STEREOLOGICAL ESTIMATION OF GONAD VOLUME AND OOCYTE NUMBER IN A SPECIMEN OF A NATIVE CLAM (VENERUPIS PULLASTRA)
Authors: Fariña Pablo Alvarez , Gual-Arnau Ximo
Published: July 2011

We obtained the gonad volume and oocyte number in a single Venerupis pullastra (Montagu, 1803) using unbiased stereological estimators. Since the gonad is not a fixed anatomical structure and is merged with other organs in the clam, we used new variance expressions to study the efficiency of these estimators, where the isotropy condition is not required for the covariogram.
QUANTITATIVE CONFOCAL LASER SCANNING MICROSCOPY
Authors: Raarup Merete Krog , Nyengaard Jens Randel
Published: July 2011

This paper discusses recent advances in confocal laser scanning microscopy (CLSM) for imaging of 3D structure as well as quantitative characterization of biomolecular interactions and diffusion behaviour by means of one- and two-photon excitation. The use of CLSM for improved stereological length estimation in thick (up to 0.5 mm) tissue is proposed. The techniques of FRET (Fluorescence Resonance Energy Transfer), FLIM (Fluorescence Lifetime Imaging Microscopy), FCS (Fluorescence Correlation Spectroscopy) and FRAP (Fluorescence Recovery After Photobleaching) are introduced and their applicability for quantitative imaging of biomolecular (co-)localization and trafficking in live cells described. The advantage of two-photon versus one-photon excitation in relation to these techniques is discussed.
APPLICATION OF A LATTICE GAS MODEL FOR SUBPIXEL PROCESSING OF LOW-RESOLUTION IMAGES OF BINARY STRUCTURES
Authors: Tabor Zbisław
Published: July 2011

In the study an algorithm based on a lattice gas model is proposed as a tool for enhancing quality of lowresolution images of binary structures. Analyzed low-resolution gray-level images are replaced with binary images, in which pixel size is decreased. The intensity in the pixels of these new images is determined by corresponding gray-level intensities in the original low-resolution images. Then the white phase pixels in the binary images are assumed to be particles interacting with one another, interacting with properly defined external field and allowed to diffuse. The evolution is driven towards a state with maximal energy by Metropolis algorithm. This state is used to estimate the imaged object. The performance of the proposed algorithm and local and global thresholding methods are compared.
SIZE AND SHAPE FACTOR EXTREMES OF SPHEROIDS
Authors: Hlubinka Daniel
Published: July 2011

In the paper we consider random prolate (oblate) spheroids and their random profiles. The limiting distribution of the extremal characteristics of the spheroids is related to the limiting distribution of the corresponding extremal characteristics of the profiles. The difference between the analysis of the prolate and oblate spheroids is discussed. We propose the possible application of the theoretical results.
3D CHARACTERIZATION OF WOOD BASED FIBROUS MATERIALS: AN APPLICATION
Authors: Lux Jérôme , Delisée Christine , Thibault Xavier
Published: July 2011

Morphological characterization of wood based fibrous materials is carried out using X-ray tomography. This technique allows the non destructive observation at the scales of a fibre (microscopic scale) and of a network of fibres (mesoscopic scale). The 3D images are processed using classical tools of mathematical morphology. Measures of porosities and estimations of the size distributions of fibres and pores are carried out and compared to other results. An alternative method for the calculation of the local orientation of the fibres is also described to quantify the anisotropy of the fibres network. Finally, the individualization of the fibres is obtained from the representation of the fibrous network as a 3D skeleton, making possible further measurements on the isolated fibres.
PRACTICAL DETERMINATION OF THE COORDINATION NUMBER IN GRANULAR MEDIA
Authors: Jouannot-Chesney Patricia , Jernot Jean-Paul , Lantuéjoul Christian
Published: July 2011

In a random stacking of particles, the coordination number is defined as the mean number of particles touching a given one. A classical measurement by image analysis is directly based on this definition. It can be applied in the theoretical case of a global analysis but some problems occur for practical applications. We propose here a new measurement method based on the contribution to the Euler-Poincaré characteristic. A single measurement is performed both on the initial structure (particles linked by contacts) and on the segmented structure (isolated particles). The proposed method is robust w.r.t. the shape of the particles and their contacts.
GEOMETRIC IDENTITIES IN STEREOLOGICAL PARTICLE ANALYSIS
Authors: Kötzer Stephan
Published: July 2011

The paper reviews recent findings about geometric identities in integral geometry and geometric tomography, and their statistical application to stereological particle analysis. Open questions are discussed. This survey can also serve as an introduction to modern stereological particle analysis for readers who are interested in the mathematical background of the new methods.
MODERN ROUTES TO EXPLORE CONCRETE’S COMPLEX PORE SPACE
Authors: Stroeven Piet , Guo Zhanqi
Published: July 2011

This paper concentrates on discrete element computer-simulation of concrete. It is argued on the basis of stochastic heterogeneity theory that modern concurrent-algorithm-based systems should be employed for the assessment of pore characteristics underlying durability performance of cementitious materials. The SPACE system was developed at Delft University of Technology for producing realistic schematizations of realcrete for a wide range of other particle packing problems, involving aggregate and fresh cement, and for the purpose of exploring characteristics in the hardened state of concrete, including of the pore network structure because of obvious durability problems. Since structure-sensitive properties are involved, schematization of reality should explicitly deal with the configuration of the cement particles in the fresh state. The paper concentrates on the stereological and mathematical morphology operations executed to acquire information on particle size, global porosity, and on distribution of porosity and of the connected pore fraction as a result of the near neighbourhood of aggregate grains. Goal is to provide information obtained along different exploration routes of concrete's pore space for setting up a pore network modelling approach. This type of methodological papers is scarce in concrete technology, if not missing at all. Technical publications that report on obtained results in our investigations are systematically referred to.
AUTOMATIC SEGMENTATION AND CLASSIFICATION OF CELLS FROM BRONCHO ALVEOLAR LAVAGE
Authors: Lezoray Olivier , Lecluse Michel
Published: July 2011

Broncho alveolar lavage is the most commonly used diagnostic tool for confirming alveolar hemorrhage. Golde has introduced a ranking score, based on the hemosiderin content of macrophages which enables ranking cells from 0 to 4 based on the degree of Prussian blue stain. We propose a complete image analysis scheme to automatically perform both the extraction of the cellular objects and the ranking of each cell according to the Golde score. The image analysis techniques used mainly involve clustering and mathematical morphology. A 2D histogram is clustered to extract the main cellular components, a color watershed is used to determine and refine the regions. Finally, the cellular components of interest are firstly classified according to their hue and secondly according to their staining repartition. The proposed image analysis technique is very fast and produces reliable and accurate results.
PERCOLATION OF RANDOM CYLINDER AGGREGATES
Authors: Jeulin Dominique , Moreaud Maxime
Published: July 2011

The percolation threshold ρc of Boolean models of cylinders with their axis parallel to a given direction is studied by means of simulations. An efficient method of construction of percolating connected components was developed, and is applied to one or two scales Boolean model, in order to simulate the presence of aggregates. The invariance of the percolation threshold with respect to affine transformations in the common direction of the axis of cylinders is approximately satisfied on simulations. The prediction of the model (ρc close to 0.16) is consistent with experimental measurements on plasma spray coatings, which motivated this study.
UNBIASED ESTIMATORS OF SPECIFIC CONNECTIVITY
Authors: Jernot Jean-Paul , Jouannot Patricia , Lantuéjoul Christian
Published: July 2011

This paper deals with the estimation of the specific connectivity of a stationary random set in IRd. It turns out that the "natural" estimator is only asymptotically unbiased. The example of a boolean model of hypercubes illustrates the amplitude of the bias produced when the measurement field is relatively small with respect to the range of the random set. For that reason unbiased estimators are desired. Such an estimator can be found in the literature in the case where the measurement field is a right parallelotope. In this paper, this estimator is extended to apply to measurement fields of various shapes, and to possess a smaller variance. Finally an example from quantitative metallography (specific connectivity of a population of sintered bronze particles) is given.
CHARACTERIZATION OF MAMMARY GLAND TISSUE USING JOINT ESTIMATORS OF MINKOWSKI FUNCTIONALS
Authors: Mattfeldt Torsten , Meschenmoser Daniel , Pantle Ursa , Schmidt Volker
Published: July 2011

A theoretical approach to estimate the Minkowski functionals, i.e., area fraction, specifc boundary length and specifc Euler number in 2D, and their asymptotic covariance matrix proposed by Spodarev and Schmidt (2005) and Pantle et al. (2006a;b) is applied to real image data. These two-dimensional images show mammary gland tissue and should be classifed automatically as tumor-free or mammary cancer, respectively. The estimation procedure is illustrated step-by-step and the calculations are described in detail. To reduce dependencies from chosen parameters, a least-squares approach is considered as recommended by Klenk et al. (2006). Emphasis is placed on the detailed description of the estimation procedure and the application of the theory to real image data.
SELF-HEALING CAPACITY OF CONCRETE - COMPUTER SIMULATION STUDY OF UNHYDRATED CEMENT STRUCTURE
Authors: He Huan , Guo Zhanqi , Stroeven Piet , Stroeven Martijn , Sluys Lambertus Johannes
Published: July 2011

Aggregate occupies at least three-quarters of the volume of concrete, so its impact on concrete's properties is large. The aggregate's influence on the non-hydrated part of the matured paste is assessed by concurrent algorithm-based computer simulation system SPACE in this paper. A distinction is made between interfacial zones (ITZs) and bulk paste. Containers with rigid boundaries were employed for the production of series of cement pastes. They were subjected to quantitative microstructure analysis. Relevant gradient structures in the ITZ and bulk are presented and discussed. The relevance of this structure information for possible selfhealing of cracks is briefly discussed.
3-D STUDY OF VESSELS IN PERIPHERAL PLACENTAL VILLI
Authors: Jirkovská Marie , Kubínová Lucie , Janáček Jiří , Kaláb Josef
Published: July 2011

The microvascular bed of the human term placenta is located in the mature intermediate and terminal villi. Despite repeated studies, a commonly accepted model of its spatial organization is not yet available. In the present study, the 3-D arrangement of vessels in mature intermediate and terminal placental villi was examined using the combination of confocal microscopy and image processing. Fixed and paraffin embedded placental samples were cut into 120 μm thick sections. Serial optical sections were captured by a confocal microscope and used as an initial data for 3-D reconstruction. The reconstructed segments of the villous tree show parallel vessels of mature intermediate villi giving rise to the capillaries of terminal villi. The signs of longitudinal and sprouting capillary growth as well as growth of new villi were observed. The presented method allowed us to visualize large parts of peripheral placental villi, which is useful for elucidating the arrangement of their vascular bed.
LOCAL GEOMETRICAL ANALYSIS OF 3D POROUS NETWORKS BASED ON THE MEDIAL AXIS: APPLICATION TO BONE MICROARCHITECTURE MICROTOMOGRAPHY IMAGES
Authors: Peyrin Françoise , Peter Zsolt , Larrue Aymeric , Bonnassie Alexandra , Attali Dominique
Published: July 2011

This paper proposes a new method for local evaluation the geometry of complex 3D porous networks such as bone micro-architecture. The method described here allows local quantification of the geometry of the entire volume. It is well adapted to high resolution images where the voxel size is smaller than the structure thickness. The classification of each point on the medial axis is based on a local topological analysis of a neighbourhood, the size of which is adapted locally to the studied point. This property makes this classification more robust to the small irregularities that may appear in a real biological data set. After classification, new quantitative parameters of bone micro-architecture characterizing plate and rod structures are independently defined. The method is quantitatively evaluated on numerical phantoms presenting shape irregularities. Application to experimental 3D bone microtomographic images shows that the method provides visually correct results, even on complex natural trabecular structures. The additional geometrical parameters provided by this method allow discrimination of volumes whose porosity and mean thickness are similar.
SHTEREOM I SIMPLE WINDOWS® BASED SOFTWARE FOR STEREOLOGY. VOLUME AND NUMBER ESTIMATIONS
Authors: Oğuz Emin Oğuzhan , Çonkur Erdinç Şahin , Sari Murat
Published: July 2011

Stereology has been earlier defined by Wiebel (1970) to be: "a body of mathematical methods relating to three dimensional parameters defining the structure from two dimensional measurements obtainable on sections of the structure." SHTEREOM I is a simple windows-based software for stereological estimation. In this first part, we describe the implementation of the number and volume estimation tools for unbiased design-based stereology. This software is produced in Visual Basic and can be used on personal computers operated by Microsoft Windows® operating systems that are connected to a conventional camera attached to a microscope and a microcator or a simple dial gauge. Microsoft NET Framework version 1.1 also needs to be downloaded for full use. The features of the SHTEREOM I software are illustrated through examples of stereological estimations in terms of volume and particle numbers for different magnifications (4X–100X). Point-counting grids are available for area estimations and for use with the most efficient volume estimation tool, the Cavalieri technique and are applied to Lizard testicle volume. An unbiased counting frame system is available for number estimations of the objects under investigation, and an on-screen manual stepping module for number estimations through the optical fractionator method is also available for the measurement of increments along the X and Y axes of the microscope stage for the estimation of rat brain hippocampal pyramidal neurons.
GRADUAL TRANSITION DETECTION FOR VIDEO PARTITIONING USING MORPHOLOGICAL OPERATORS
Authors: Naranjo Valery , Angulo Jesús , Albiol Antonio , Mossi Jose M , Albiol Alberto , Gómez Soledad
Published: July 2011

Temporal segmentation of video data for partitioning the sequence into shots is a prerequisite in many applications: automatic video indexing and editing, old flm restoration, perceptual coding, etc. The detection of abrupt transitions or cuts has been thoroughly studied in previous works. In this paper we present a scheme to identify the most common gradual transitions, i.e., dissolves and wipes, which relies on mathematical morphology operators. The approach is restricted to fast techniques which require low computation (without motion estimation and adapted to compressed sequences) and are able to cope with random brightness variations (often occurring in old flms). The present study illustrates how the morphological operators can be used to analyze temporal series for detecting particular events, either working directly on the 1D signal or building an intermediate 2D image from the 1D signals to take advantage of the spatial operators.
ADAPTIVE CROSSING NUMBERS AND THEIR APPLICATION TO BINARY DOWNSAMPLING
Authors: Decencière Etienne , Bilodeau Michel
Published: July 2011

A downsampling method for binary images is presented, which aims at preserving the topology of the image. It uses a general reference sampling structure. The reference image is computed through the analysis of the connected components of the neighbourhood of each pixel. The resulting downsampling operator is autodual, which ensures that white and black structures are treated in the same way. Experiments show, by visual inspection on the displayed images, that the image topology is indeed preserved satisfactorily.
COMPUTATION OF MINKOWSKI MEASURES ON 2D AND 3D BINARY IMAGES
Authors: Legland David , Kiêu Kiên , Devaux Marie-Françoise
Published: July 2011

Minkowski functionals encompass standard geometric parameters such as volume, area, length and the Euler-Poincaré characteristic. Software tools for computing approximations of Minkowski functionals on binary 2D or 3D images are now available based on mathematical methods due to Serra, Lang and Ohser. Minkowski functionals can not be used to describe spatial heterogeneity of structures. This description can be performed by using Minkowski measures, which are local versions of Minkowski functionals. In this paper, we discuss how to extend the computation of Minkowski functionals to the computation of Minkowski measures. Approximations of Minkowski measures are computed using fltering and look-up table transformations. The final result is represented as a grey-level image. Approximation errors are investigated based on numerical examples. Convergence and non convergence of the measure approximations are discussed. The measure of surface area is used to describe spatial heterogeneity of a synthetic structure, and of an image of tomato pericarp.
CELL PROLIFERATION AND VOLUME-WEIGHTED MEAN NUCLEAR VOLUME IN HIGH-GRADE PIN AND ADENOCARCINOMA, COMPARED WITH NORMAL PROSTATE
Authors: Teba Fernando , Martín Rocío , Gómez Vicente , Herranz Luis M , Santamaría Luis
Published: July 2011

High-grade prostate intraepithelial neoplasia (PIN) is considered a precursor of prostate adenocarcinoma. The aim of this study was to quantitate the differences between basal and luminal cells of PIN in relation to mean nuclear volume (νVnuc), and proliferating cell nuclear antigen labeling index (LIPCNA), and to compare these estimates with those obtained in normal prostate and carcinoma. The epithelium of both normal and PIN specimens was segmented in basal and luminal compartments, and the νVnuc and LIPCNA measured in both strata. νVnuc was significantly lower in normal epithelium than in both PIN and carcinoma. The νVnuc of basal layer of PIN was significantly higher than in luminal stratum. The luminal νVnuc was similar in both PIN and adenocarcinoma. The LIPCNA was greater in PIN and adenocarcinoma than in normal glands. The LIPCNA of basal cells from PIN was similar to that observed in the basal stratum from normal prostate, whereas the luminal proliferation from PIN was similar to that observed in adenocarcinoma. The similarities in nuclear size between PIN and carcinoma are according to the premalignant haracter of PIN. The increase of basal νVnuc in PIN indicates that the changes heralding the progression from PIN to carcinoma are produced in this layer, whereas the nuclear features of the luminal layer are the same to those of the carcinoma. These remarks make sense in reference to the progression of malignant changes from PIN basal layer to PIN luminal layer and from this to carcinoma.
NUCLEI SHAPE ANALYSIS, A STATISTICAL APPROACH
Authors: Nettel-Aguirre Alberto
Published: July 2011

The method presented in our paper suggests the use of Functional Data Analysis (FDA) techniques in an attempt to characterise the nuclei of two types of cells: Cancer and non-cancer, based on their 2 dimensional profiles. The characteristics of the profile itself, as traced by its X and Y coordinates, their first and second derivatives, their variability and use in characterization are the main focus of this approach which is not constrained to star shaped nuclei. Findings: Principal components created from the coordinates relate to shape with significant differences between nuclei type. Characterisations for each type of profile were found.
POLAR MODELLING AND SEGMENTATION OF GENOMIC MICROARRAY SPOTS USING MATHEMATICAL MORPHOLOGY
Authors: Angulo Jesús
Published: July 2011

Robust image analysis of spots in microarrays (quality control + spot segmentation + quantification) is a requirement for automated software which is of fundamental importance for a high-throughput analysis of genomics microarray-based data. This paper deals with the development of model-based image processing algorithms for qualifying/segmenting/quantifying adaptively each spot according to its morphology. A series of morphologicalmodels for spot intensities are introduced. The spot typologies representmost of the possible qualitative cases identified from a large database (different routines, techniques, etc.). Then, based on these spot models, a classification framework has been developed. The spot feature extraction and classification (without segmenting) is based on converting the spot image to polar coordinates and, after computing the radial/angular projections, the calculation of granulometric curves and derived parameters from these projections. Spot contour segmentation can also be solved by working in polar coordinates, calculating the up/downminimal path, which is easily obtained with the generalized distance function. With this model-based technique, the segmentation can be regularised by controlling different elements of the algorithm. According to the spot typology (e.g., doughnut-like or egg-like spots), several minimal paths can be computed to obtain a multi-region segmentation. Moreover, this segmentation is more robust and sensible to weak spots, improving the previous approaches.
APPLICATION OF STEREOLOGICAL METHODS TO STUDY THE WHITE MATTER AND MYELINATED FIBERS THEREIN OF RAT BRAIN
Authors: Yang Shu , Li Chen , Zhang Wei , Wang Weiwei , Nyengaard Jens R , Tang Yong
Published: July 2011

An efficient and unbiased stereological method was applied to estimate the white matter volume, the total volume, total length and mean diameter of the myelinated fibers in the white matter and the total volume of the myelin sheaths in the white matter of rat brain. The white matter volume was obtained with the Cavalieri principle. Four tissue blocks were sampled from the entire white matter in a uniform random fashion. The length density of the myelinated fibers in the white matter was obtained from the isotropic, uniform, random sections ensured by the isector. The volume density of the myelinated fibers in the white matter was estimated by point counting. The total length and the total volume of the myelinated fibers in the white matter were estimated by multiplying the white matter volume and the length density and the volume density of the myelinated fibers in the white matter, respectively. The size of nerve fibers was derived by measuring the profile diameter perpendicular to its longest axis. The results were satisfactory in the sense that the sampling variance introduced by the stereological estimation procedure was a minor fraction of the observed variance. The comparison of the white matter and the myelinated fibers in the white matter between rat brain and human brain was also made in the present study.
NEURON AND GLIAL CELL NUMBERS IN THE MEDIODORSAL THALAMIC NUCLEUS IN BRAINS OF SCHIZOPHRENIC SUBJECTS
Authors: Nielsen Rune Damgaard , Abitz Maja , Pakkenberg Bente
Published: July 2011

Several stereological studies of schizophrenic subjects have shown reduction in both the total number of neurons and in the total volume of the mediodorsal thalamic nucleus (MD). This is in contrast to other studies in that no differences have been found. Using systematic random sampling and an optical fractionator design, the total number of neuron and glial cells in the MD subdivisions: parvocellular (MDPC), magnocellular (MDMC), and densocellular (MDDC) were counted in brains from 9 schizophrenic and 8 control subjects. The control subjects were age, height and body-weight matched to the schizophrenic subjects. We found the neuronal numbers in the schizophrenic subjects to range more than a factor of two, from 3.68 to 9.22 x 106. This is in contrast to the control subjects, who ranged from 5.24 to 7.10 x 106 in neuronal cell numbers. Within our inhomogeneous sample, some schizophrenic subjects thus exhibited relative high total neuron numbers in MD, while others exhibited relative low neuron numbers. The result is in line with the heterogeneity of this severe mental disease and may help to explain why different research groups get different results. The major limitation in this study is the small number of brains of schizophrenic subjects with a high degree of inhomogeneity in length of disease and age of onset. The debates of the comparison of the neurons in the MD in brains of schizophrenic subjects and control subjects and the possible impact of this variance on the disease are still not complete.
SAMPLING INTENSITY WITH FIXED PRECISION WHEN ESTIMATING VOLUME OF HUMAN BRAIN COMPARTMENTS
Authors: Maudsley Rhiannon , García-Fiñana Marta
Published: July 2011

Cavalieri sampling and point counting are frequently applied in combination with magnetic resonance (MR) imaging to estimate the volume of human brain compartments. Current practice involves arbitrarily choosing the number of sections and sampling intensity within each section, and subsequently applying error prediction formulae to estimate the precision. The aim of this study is to derive a reference table for researchers who are interested in estimating the volume of brain regions, namely grey matter, white matter, and their union, to a given precision. In particular, this table, which is based on subsampling of a large brain data set obtained from coronal MR images, offers a recommendation for the minimum number of sections and mean number of points per section that are required to achieve a pre-defined coefficient of error of the volume estimator. Further analysis onMR brain data from a second human brain shows that the sampling intensity recommended is appropriate.
3D MULTI-SCALE SEGMENTATION OF GRANULAR MATERIALS
Authors: Tariel Vincent , Jeulin Dominique , Fanget Alain , Contesse Gérald
Published: July 2011

On a microscopic scale, a pyrotechnic material is made of a polymer matrix containing grains with different sizes and shapes. Its physical behaviour can be predicted by homogenization. Information about the morphology of the grains can be obtained by different ways. One of these ways is 3D image processing. This has been made easier by the use of a new imaging technique, the microtomography, allowing fast threedimensional reconstruction and processing. In this paper images of two granular materials are segmented by means of 3D mathematicalmorphology algorithms, based on a multi-scale extraction of markers for watershed segmentation.
MEAN VALUES FOR HOMOGENEOUS STIT TESSELLATIONS IN 3D
Authors: Nagel Werner , Weiss Viola
Published: July 2011

Recently (Nagel and Weiss, 2005), the class of homogeneous random tessellations that are stable under the operation of iteration (STIT) was introduced. In the present paper this model is reviewed and new results for the mean values of essential geometric features of STIT tessellations in two and three dimensions are provided and proved. For the isotropic model, these mean values are compared with those ones of the Poisson-Voronoi and of the Poisson plane tessellations, respectively.
REGION MERGING VIA GRAPH-CUTS
Authors: Stawiaski Jean , Decenciére Etienne
Published: July 2011

In this paper, we discuss the use of graph-cuts to merge the regions of the watershed transform optimally. Watershed is a simple, intuitive and efficient way of segmenting an image. Unfortunately it presents a few limitations such as over-segmentation and poor detection of low boundaries. Our segmentation process merges regions of the watershed over-segmentation by minimizing a specific criterion using graph-cuts optimization. Two methods will be introduced in this paper. The first is based on regions histogram and dissimilarity measures between adjacent regions. The second method deals with efficient approximation of minimal surfaces and geodesics. Experimental results show that these techniques can efficiently be used for large images segmentation when a pre-computed low level segmentation is available. We will present these methods in the context of interactive medical image segmentation.