An X-ray Microtomography Study of the Effect of an Experimental Statherin-like Peptide on Demineralisation and Remineralisation...
The salivary protein, statherin, plays an important role in enamel homeostasis. It forms a bioactive complex with calcium and phosphate releasing these ions when pH decreases. Statherin also forms part of the enamel pellicle forming a protective barrier against bacterial and dietary acids. The purpose of this thesis was two-fold: firstly, to study the effect of a 21 amino acid peptide identical to the N terminus of Statherin (StN21) on enamel de - and remineralisation in vitro and secondly, to undertake biocompatibility assays of this peptide to demonstrate its safety for use in a clinical trial. X-ray microtomography (XMT) is a quantitative, non-destructive method of measuring mineral change. Using XMT to quantify mineral changes, StN21 demonstrated a statistically significant decrease in demineralisation rate when compared to control lesions exposed to phosphate buffered saline (PBS). Whole Statherin protein and sodium fluoride solutions were used as ...https://qmro.qmul.ac.uk/xmlui/handle/123456789/11580
Characterization of interfacial stress transfer ability in acetylation-treated wood fibre composites using X-ray microtomography
The properties of the fibre/matrix interface contribute to stiffness, strength and fracture behaviour of fibre-reinforced composites. In cellulosic composites, the limited affinity between the hydrophilic fibres and the hydrophobic thermoplastic matrix remains a challenge, and the reinforcing capability of the fibres is hence not fully utilized. A direct characterisation of the stress transfer ability through pull-out tests on single fibres is extremely cumbersome due to the small dimension of the wood fibres. Here a novel approach is proposed: the length distribution of the fibres sticking out of the matrix at the fracture surface is approximated using X-ray microtomography and is used as an estimate of the adhesion between the fibres and the matrix. When a crack grows in the material, the fibres will either break or be pulled-out of the matrix depending on their adhesion to the matrix: good adhesion between the fibres and the matrix should result in more fibre breakage and ...http://ri.diva-portal.org/smash/record.jsf?pid=diva2:1086516
Observer-dependent variability of the thresholding step in the quantitative analysis of soil images and X-ray microtomography...
TY - JOUR. T1 - Observer-dependent variability of the thresholding step in the quantitative analysis of soil images and X-ray microtomography data. AU - Baveye,Philippe C.. AU - Laba,Magdeline. AU - Otten,Wilfred. AU - Bouckaert,Liesbeth. AU - Goswami,Rohit R.. AU - Grinev,Dmitri V.. AU - Houston,Alasdair N.. AU - Hu,Yaoping. AU - Liu,Jianli. AU - Mooney,Sacha. AU - Sleutel,Steven. AU - Tarquis,Ana. AU - Wang,Wei. AU - Wei,Qiao. AU - Sezgin,Mehmet. PY - 2010/6. Y1 - 2010/6. N2 - For the investigation of many geometrical features of soils, computer-assisted image analysis has become a method of choice over the last few decades. This analysis involves numerous steps, regarding which subjective decisions have to be made by the individuals conducting the research. This is particularly the case with the thresholding step, required to transform the original (color or greyscale) images into the type of binary representation (e.g., pores in white, solids in black) needed for fractal ...https://rke.abertay.ac.uk/en/publications/observer-dependent-variability-of-the-thresholding-step-in-the-qu
Application of differential effective medium, magnetic pore fabric analysis, and X-ray microtomography to calculate elastic...
Application of differential effective medium, magnetic pore fabric analysis, and X-ray microtomography to calculate elastic properties of porous and anisotropic rock ...https://www.research-collection.ethz.ch/handle/20.500.11850/30381
Impact of flavour solvent on biscuit micro-structure as measured by X-ray micro-computed tomography and the distribution of...
The influence of flavour solvent, propylene glycol (PG) and triacetin (TA), was investigated on the micro-structure (as measured by X-ray micro-Computed Tomography, X-ray μCT) and aroma compound distribution (as measured by HPLC) within shortcake biscuits. X-ray μCT scanning showed biscuits made with PG had smaller pores and higher porosity than biscuits made with TA. Vanillin distribution across the biscuits was not homogeneous and was found at higher concentrations in the centre of the biscuits than the edge or bottom. The baked aroma compound 5-hydroxymethyl-furfural (HMF) was present at higher concentrations at the surface of the biscuits where Maillard chemistry is presumed to occur at its highest rate. The type of solvent had a significant effect on the total concentration and distribution of aroma compounds (p , 0.05). TA biscuits retained greater vanillin and more HMF was formed during baking when compared to PG biscuits. The core of TA biscuits had ...http://eprints.nottingham.ac.uk/2629/
Three-dimensional murine airway segmentation in micro-CT images | (2007) | Shi | Publications | Spie
Thoracic imaging for small animals has emerged as an important tool for monitoring pulmonary disease progression and therapy response in genetically engineered animals. Micro-CT is becoming the standard thoracic imaging modality in small animal imaging because it can produce high-resolution images of the lung parenchyma, vasculature, and airways. Segmentation, measurement, and visualization of the airway tree is an important step in pulmonary image analysis. However, manual analysis of the airway tree in micro-CT images can be extremely time-consuming since a typical dataset is usually on the order of several gigabytes in size. Automated and semi-automated tools for micro-CT airway analysis are desirable. In this paper, we propose an automatic airway segmentation method for in vivo micro-CT images of the murine lung and validate our method by comparing the automatic results to manual tracing. Our method is based primarily on grayscale morphology. The results show good visual matches between ...http://spie.org/Publications/Proceedings/Paper/10.1117/12.711213
Lizard, micro-CT scan - Stock Image C021/7082 - Science Photo Library
Lizard (Leiocephalus sp.) micro-CT scan. This is the type specimen for this species. Types are the original example against which all descriptions are compared. Types are therefore both scientifically valuable and in demand from researchers wishing to study them. Micro-CT was used to create a virtual copy of this type specimen to help build a digital collection. This image was acquired using X-ray micro-Computed Tomography (also known as micro-CT). A micro-CT scanner projects a beam of X-rays through the sample onto a detector panel. Images are collected over a 360Â° rotation and these are then reconstructed to form a virtual 3D model of the specimen. This virtual object that can be viewed from all angles and sliced open or digitally dissected. Image by Dan Sykes. - Stock Image C021/7082http://www.sciencephoto.com/media/621553/view
Micro-CTvlab: A web based virtual gallery of biological specimens using X-ray microtomography (micro-CT)
The Micro-CTvlab offers to the user virtual image galleries of various taxa which can be displayed and downloaded through a web application. With a few clicks, accurate, detailed and three-dimensional models of species can be studied and virtually dissected without destroying the actual specimen. The data and functions of the Micro-CTvlab can be accessed either on a normal computer or through a dedicated version for mobile devices.https://bdj.pensoft.net/article/8740
Applications of X-ray microtomography in material and life sciences - Léonard Angélique
Université de Liège - ULg , Département de chimie appliquée , Génie chimique - Opérations physiques unitaires - Département de chimie appliquée ,] ...http://orbi.ulg.ac.be/handle/2268/17553
An optimization procedure for spatial and density resolution in hard X-ray micro-computed tomography - ePrints Soton
The quality of the X-ray tomogram not only depends on the spatial resolution but also on the density resolution or contrast. Based on the theory of [Nucl. Instr. and Meth. 206 (1983) 541] it is concluded that the density resolution can be substantially improved by merging of pixels, referred to as binning, prior to reconstruction. We demonstrate that the quality of a given 3D-data set, i.e. the tomogram of stained biological cells seeded on a polymer multifilament yarn in phosphate buffered saline, can be optimized with respect to the product of spatial and density resolution - the image quality factor. This procedure improves or even enables the visualization and quantification of selected constituents in the tomogram.. Full text not available from this repository.. ...https://eprints.soton.ac.uk/48923/
X-ray Micro-CT Microtomography - Material Science Micro-CT Product Line for Research | Bruker
Bruker microCT can genuinely claim to be at the fore-front of the development of high performance micro-CT technology. Our research and development of 3D x-ray microscopy started in the early 1980s. This led to the first micro-CT imaging results being obtained in 1983-1987 and published in scientific journals and international conferences proceedings. Building on this early work, Bruker-microCT was founded in 1996, and within a year we were manufacturing a commercially available micro-CT scanner with spatial resolution in the micron range. In 2001 we produced the first high-resolution in vivo micro-CT scanner for small animal imaging. And in 2005 Bruker-microCTbecame the world's only supplier of a laboratory nano-CT scanner with submicron spatial resolution. Responding to demand from the growing community of micro-CT users, we are continually active in research and development into new methods for non-destructive 3D microscopy. ...https://www.bruker.com/products/microtomography/micro-ct-for-sample-scanning/x-ray-micro-ct-microtomography.html
3D SEISMIC TOMOGRAPHY ANALYSIS OF JAPAN SUBSTRUCTURE USING LOCAL EARTHQUAKE TOMOGRAPHY - Lumbung Pustaka UNY
Wilujeng, Indrawati and Santosa, Bagus Jaya 3D SEISMIC TOMOGRAPHY ANALYSIS OF JAPAN SUBSTRUCTURE USING LOCAL EARTHQUAKE TOMOGRAPHY. Proceeding of International Conference On Research, Implementation And Education Of Mathematics And Sciences 2015. ISSN 978-979-96880-8-8 ...http://eprints.uny.ac.id/21053/
X-ray computed tomography analysis of damage evolution in open hole carbon fiber-reinforced laminates subjected to in-plane...
F. Sket, A. Enfedaque, C. Díaz López, C. González, J. Molina-Aldareguía, J. LLorca. X-ray computed tomography analysis of damage evolution in open hole carbon fiber-reinforced laminates subjected to in-plane shear. Composites Science and Technology 133, 40-50, 2016. DOI:10.1016/j.compscitech.2016.06.012. ...http://materials.imdea.org/x-ray-computed-tomography-analysis-of-damage-evolution-in-open-hole-carbon-fiber-reinforced-laminates-subjected-to-in-plane-shear/
ICTP - (Synchrotron) light shed on ancient fossils
In an article about the study published by Italian newspaper La Repubblica, Nava declared "The woman's teeth could provide us information about her diet and her movements but not on her health condition, as they were not growing. Conversely, the milk teeth of the fetus tracks periods of good and bad health while forming, from the 3rd to 4th month of gestation, till they drop. Layers add up daily, which allow us to precisely follow the development of the baby. It's similar to what happens with tree rings." . The research team visualized and analyzed three still-forming incisors belonging to the fetus by means of X-ray microtomography. By studying the 108 enamel layers in these milk teeth, scientists could investigate the condition of both the mother and the fetus. Results showed that three severe physiological stresses affecting both individuals occurred during the last two and a half months of pregnancy. This was highlighted by the presence of microscopic stress markers ...http://www.ictp.it/about-ictp/media-centre/news/2017/9/paleoliticteeth.aspx
Publikacje pracowników PL
This paper presents the possibility of applying the finite element method for the analysis of stress level in hard dental tissues, restored with class I dental filling and exposed to mechanical load. The studies were made on a geometrical model imitating the real geometry of a premolar tooth obtained using the X-ray microtomography technique and CAD software. The distributions of reduced stress defined in accordance with the Huber-Mises-Hencky (H-M-H) hypothesis in hard dental tissues were analysed, and assessment of the degree of strength of the adhesive layer at the border of the composite filling and biological tissue was attempted. The application of numerical simulations (Abaqus) enables real assessment of the tooth tissue strength, which allows assessing the risk of unsuccessful dental treatment, and helps to prepare rational methods of preventing tooth damage resulting from mechanical load ...http://pub.pollub.pl/publikacje/3550/
Natural deformation of rocks is commonly associated with development of mineralogical layering, leading to irreversible transformations of their microstructure. The mechanisms of such chemical differentiation processes during diagenesis, tectonics, metamorphism, or fault differentiation remain poorly understood, as they are difficult to reproduce experimentally due to the very slow kinetics involved. This paper shows that development of differentiated layering, similar to that observed in natural deformation, is stress driven and can be obtained from indenter experiments. Samples of (1) gypsum plaster mixed with clay, and (2) natural diatomite loosely interbedded with volcanic ash, saturated with aqueous solutions in equilibrium, were subjected to loading for several months at 40 °C and 150 °C, respectively. X-ray microtomography and scanning electron microscopy observations show that layering develops by a self-organized pressure solution process. Stress-driven dissolution ...http://geology.geoscienceworld.org/content/early/2015/08/28/G36713.1
The impact of green roof ageing on substrate characteristics and hydrological performance - White Rose Research Online
Green roofs contribute to stormwater management through the retention of rainfall and the detention of runoff. However, there is very limited knowledge concerning the evolution of green roof hydrological performance with system age. This study presents a non-invasive technique which allows for repeatable determination of key substrate characteristics over time, and evaluates the impact of observed substrate changes on hydrological performance. The physical properties of 12 green roof substrate cores have been evaluated using non-invasive X-ray microtomography (XMT) imaging. The cores comprised three replicates of two contrasting substrate types at two different ages: unused virgin samples; and 5-year-old samples from existing green roof test beds. Whilst significant structural differences (density, pore and particle sizes, tortuosity) between virgin and aged samples of a crushed brick substrate were observed, these differences did not significantly affect hydrological ...http://eprints.whiterose.ac.uk/113083/
Last Week on ResearchBlogging.org - Page 3.14
Scientists use a 'gene gun' to insert a gene from a flowering plant called rockcress into the cells of wheat seeds. The genetically modified wheat became more resistant to a fungus called take-all, which in real life can cause "a 40-60% reduction in wheat yields.". T-cells from six HIV+ patients were removed from their bodies, treated with a zinc-finger nuclease designed to snip a gene out of the cell's DNA, and put back in the patients. Removal of the gene mimics a naturally occurring mutation which confers resistance to the HIV virus. But only 25% of the treated cells showed evidence of being successfully edited.. Researchers "use time-resolved X-ray microtomography to visualize the muscles and hinges in three-dimensions" of fly wings, modelling the complex physical processes that enable flies' flight.. Even with the cost of building new energy storage infrastructure, wind energy will continue to offer a net gain of power. Plus: wind produces enough surplus electricity to ...http://scienceblogs.com/seed/2014/03/31/last-week-on-researchblogging-org-3/
CO Meeting Organizer EGU2016
Calculating structural and geometrical parameters by laboratory experiments and X-Ray microtomography: a comparative study applied to a limestone sample ...http://meetingorganizer.copernicus.org/EGU2016/orals/20964
Micro-CT, MicroCT, mikro-ct, mikroct, micro CT, Nano-CT, NanoCT, Microtomography, Nanotomography, Small animal imaging, Non...
SkyScan produces a wide range of the systems for non-invasive three-dimensional x-ray microscopy and for small animal imaging with spatial resolution in the micron range.http://bruker-microct.com
Micro-computed Tomography Lab
The primary mission of the MicroCT Laboratory is to provide state-of-the-art 3D ex vivo imaging using microCT for both research and teaching. This facility is housed within the School of Veterinary Medicine and includes a state-of-the-art ex vivo desktop cone-beam micro-CT (Scanco Model 40) that is fully shielded. This scanner has a nominal best resolution of 6µm with a real resolution of 9µm and a maximum FOV of 37mm in diameter by 70mm in length. Services can include ex vivo x-ray microCT scanning of specimens measuring no more than 35mm in diameter and 70mm in length. Software is available to provide 3D reconstructions of scanned objects, and quantify bone architecture and density. The specimens utilized for microCT must have inherent radio opacity (e.g. bone) or can be rendered radio-opaque (e.g. utilizing contrast agents). Some examples of applications of microCT include evaluation of bone microarchitecture in normal and pathogenic states (e.g. fracture healing, defect healing, in the ...http://rurallife.lsu.edu/vetmed/cbs/facilities/micro_ct_lab.php
Positron emission tomography analysis of Alzheimer's disease. - Surrey Research Insight Open Access
Alzheimer's Disease (AD) is a major concern for the elderly population, currently affecting over 670,000 people in the UK. With the continual increase in the age of the population the problem is expected to rise. There is no known cure to the condition and a definite diagnosis cannot be made in life. Clinical diagnosis is considered to be approximately 80% - 90% accurate, sometimes taking up to a year to assess. Early detection could aid in the care and possible development of better treatments or even a cure. AD has been shown to alter the structure and global texture of the brain. Studies using Magnetic Resonance imaging (MRI) and Computerised Tomography (CT) have been used to detect these changes with some success by some researchers. Positron Emission Tomography (PET) imaging is a functional imaging modality and in theory before structural changes are evident functional changes should be apparent. Therefore we utilise PET images for this study. This thesis will exploit the fact that AD ...http://epubs.surrey.ac.uk/842834/
Atom Probe Tomography analysis of magnetostrictive multilayer materials
On the right, the concentration depth profile performed along the analysis direction (depth direction) clearly reveals differences between the interfaces (dissymmetrical interfaces): the Fe/TbCo2 interface (1nm thick) is thinner than the Fe/Co interface. This effect is attributed to Fe/Co interdiffusion controlled by the establishment of the Tb layer ...http://www.cameca.com/markets/advanced-materials/magnetostrictive-materials-apt
Characterisation of gold ores by X-ray computed tomography - Part 1: Software for calibration and quantification of...
Micro-computed tomography (Micro-CT) is an X-ray imaging technique that produces highresolution 3D computerised 'virtual' models of geological specimens based on the X-ray attenuation of different materials in the specimen. The 'virtual' specimens are made up of voxels, the 3D equivalent of pixels, each assigned a gray value based on X-ray absorption. Micro-CT has enormous potential for allowing non-destructive, digital analysis of structure and composition when the mineralogical phases can be digitally separated. However, variation in X-ray flux between scans results in highly variable grayscale values for identical materials. Consequently, materials usually have to be segmented manually, which is subjective, inaccurate, labour-intensive and time consuming. Here we present a protocol and imaging software package that can be used to accurately and precisely extract quantifiable information in a repeatable ...https://espace.curtin.edu.au/handle/20.500.11937/11387
Sedimentological analysis of grain fabric has paid scant attention to grain shape. However, the information of grain orientation is inseparable from that of shape in three-dimensional fabric analysis. Not only should the dominant major-axis orientations be recognized, but so should the dominant combinations of shapes and orientations of grains. The aim of this paper is to demonstrate that such combinations can be identified by density-based cluster analysis in a five-dimensional parameter space, where a point represents a specific combination of the shape and orientation of a grain approximated by a triaxial ellipsoid. We tested the present method using an artificial data set. The data were successfully classified into correct groups. Next, we applied it to a data set obtained by X-ray computed microtomography from some 5000 sand grains deposited in an experimental flume. We show that triaxial grains, which have principal axes with distinctive radii, have major axes in the ...http://geosphere.geoscienceworld.org/content/3/2/108