Aims The practical implementation and development of the EU BIO-CT-EXPLOIT software for clearing CT data from effects of instrumental resolution [2] adds a unique and specific capability to the in house analysis GUI package “CTan” provided by SKYSCAN with its tomographic scanning equipment. Programmed in-line to sit on the "plugin" panel of the analysis package for importing tomographic image slices direct from the machine, it is a fully automated image enhancement algorithm requiring little or no expertise from the user, making it fast and easy to use in single image or indeed batch mode. The images produced use the histogram equalization technique to remove the instrumental error as documented in [1]. These may then be further processed by the main body of the SKYSCAN package according to requirement and then visualized as three-dimensional reconstructions of the computed tomography (CT) process. The incremental advances in technology in today’s market are so hard fought for that we feel confident that the unique technologies employed in this plugin concept designed for SKYSCAN will deliver a vital pre-processing step towards increasing the capability and applicability of CT scanner machines.

Stem cell based regenerative therapies involve the administration of selected stem cell populations with the purpose of repairing and regenerating damaged or diseased tissue. Currently available methods of monitoring transplanted cells are quite limited because they have to offer non-destructive strategies capable to identify the location, magnitude, and duration of cellular survival and their fate both at early and late stages. The recent development of imaging techniques offers great potential to address these critical issues by non-invasively tracking the fate of the transplanted cells. This article offers a focused presentation of some examples of the use of imaging techniques connected to the nanotechnological world in research areas related to stem cells. In particular, investigations concerning stem cell treatment of Duchenne muscular dystrophy, Infarcted Heart and bone tissue engineering in animal models are discussed.

Corresponding Author: a.giuliani@univpm.it Università Politecnica delle Marche, Dip.SAIFET, Via Brecce Bianche, Ancona, Italy; Department of Pathology and Laboratory Medicine, Section of Pathological Anatomy, University of Parma, Via Gramsci, 14, 43100 Parma, Italy; Vascular Biology and Regenerative Medicine Lab, Centro Cardiologico Monzino, Via Parea 4, 20138, Milano, Italy; A.A. Baikov Institute of Metallurgy and Materials Science, Russian Academy of Science, Leninsky prospect 49, 119991 Moscow, Russia; Dept. of Evolutionary and Functional Biology, Physiology Section, Univ. of Parma, V. le G. P. Usberti 11/A, 43100 Parma, Italy; Laboratorio di Patologia Vascolare, Istituto Dermopatico dell’Immacolata, Via dei Monti di Creta, 104, 00167 Rome, Italy; Università di Parma, Dept. Medicine and Biomedical Science, Via Gramsci, 14, 43100 Parma, Italy.

Three types of ceramic scaffolds with different composition and structure [namely synthetic 100% hydroxyapatite (HA; Engipore), synthetic calcium phosphate multiphase biomaterial containing 67% silicon stabilized tricalcium phosphate (Si-TCP; Skelite) and natural bone mineral derived scaffolds (Bio-oss)] were seeded with mesenchymal stem cells (MSC) and ectopically implanted for 8 and 16 weeks in immunodeficient mice. X-ray synchrotron radiation microtomography was used to derive 3D structural information on the same scaffolds both before and after implantation. Meaningful images and morphometric parameters such as scaffold and bone volume fraction, mean thickness and thickness distribution of the different phases as a function of the implantation time, were obtained. The used imaging algorithms allowed a direct comparison and registration of the 3D structure before and after implantation of the same sub-volume of a given scaffold. In this way it was possible to directly monitor the tissue engineered bone growth and the complete or partial degradation of the scaffold. Further, the detailed kinetics studies on Skelite scaffolds implanted for different length of times from 3 days to 24 weeks, revealed in the X-ray absorption histograms two separate peaks associated to HA and TCP. It was therefore possible to observe that the progressive degradation of the Skelite scaffolds was mainly due to the resorption of TCP. The different saturation times in the tissue engineered bone growth and in the TCP resorption confirmed that the bone growth was not limited the scaffold regions that were resorbed but continued in the inward direction with respect to the pore surface.

Porous NiTi samples were produced by two different techniques, Mechanical Alloying & Hot Pressing (MA&HP) and Reaction Synthesis (RS), followed by secondary Pulse Electric Current (PEC) treatment. The samples were analyzed by Ultra Small Angle Neutron Scattering and Computed Microtomography before and after the secondary treatment in order to investigate porosity of the samples. For the samples produced by MA&HP. PEC treatment does not cause any changes in pore size distribution for smaller pores (i.e.<10 mu m). For bigger pores, however, treatment leads to a decrease of the pore volume along with the reduction of the amount of pores. In samples processed by RS, PEC treatment led to a decrease in pore dimensions of smaller pores (up to 10 mu m), while for larger pores PEC treatment resulted in an increase in pore dimensions. Thus, the influence of secondary PEC treatment on the porosity of NiTi samples produced by the two different techniques could be confirmed and compared. Due to the pioneering character of the present work, further studies are required before using PEC treatment in future for porosity modification in a controlled manner. (C) 2009 Elsevier Ltd. All rights reserved.

Stem cell based tissue engineering therapies involve the administration of ex vivo manipulated stem cell populations with the purpose of repairing and regenerating damaged or diseased tissue. Currently available methods of monitoring transplanted cells are quite limited. To monitor the outcomes of stem cell therapy longitudinally requires the development of non-destructive strategies that are capable of identifying the location, magnitude, and duration of cellular survival and fate. The recent development of imaging techniques offers great potential to address these critical issues by non-invasively tracking the fate of the transplanted cells. This review offers a focused presentation of some examples of the use of imaging techniques connected to the nanotechnological world in research areas related to stem cells. In particular investigations will be considered concerning tissue-engineered bone, treatment of intervertebral disc degeneration, treatment by human stem cells of muscular dystrophy of Duchenne in small animal models and the repair of spinal cord injuries.

This review is presented of recent investigations concerning the structure of ceramic scaffolds and tissue-engineered bones and focused on two techniques based on X-ray radiation, namely microtomography (microCT) and microdiffraction. Bulk 3D information, with micro-resolution, is mainly obtained by microCT, whereas microdiffraction provides useful information on interfaces to the atomic scale, i.e. of the order of the nanometer. Since most of the reported results were obtained using synchrotron radiation, a brief description of the European Synchrotron Radiation Facility (ESRF) is presented, followed by a description of the two techniques. Then examples of microstructural investigations of scaffolds are reported together with studies on bone architecture. Finally, studies on ex vivo tissue-engineered bone and on bone microstructure in vivo are presented.

Grazing-incidence small-angle X-ray scattering (GISAXS) has been used to study proteins embedded in thin polymer films obtained by a new cold, atmospheric-pressure plasma technique. In order to test the efficiency of the technology, four samples of alkaline phosphatase incorporated in organic polymer coatings in different plasma conditions have been investigated. Data have been analysed in the framework of the distorted-wave Born approximation (DWBA), by using a new method for the simultaneous fitting of the two-dimensional diffuse scattering from each sample. As a result, protein film concentration and aggregation state as well as a set of parameters describing the polymer coatings have been obtained.

Residual stresses were experimentally determined in specimens of carbon-fibre composite (CFC) brazed to CuCrZr alloy, using neutron diffraction at the E3 instrument of HMI-BENSC (Berlin). The brazing was obtained by means of a Cu interlayer, one side of which was brazed to the CuCrZr alloy, after the other side was joined to CFC by a proprietary technique. Two different samples were investigated, the first one in the 'as-brazed' condition and the second one after thermal fatigue cycling [ heating of samples up to 450 degrees C followed by a fast cooling (> 1 degrees C s(-1)) to room temperature in air with water quench; the cycles were repeated 50 times for each sample]. Residual stresses were determined in the three principal directions, in the CFC and in the CuCrZr alloy, as a function of the distance from the interface with the Cu interlayer.The experimental results for the as-brazed specimen are in agreement with the results of FEM calculations available in the literature, while a relaxation of residual stresses in the thermally fatigued specimen is found to be probably ascribed to the formation of microcracks at the CFC/Cu interface.

In order to be able to reproduce historic organ reed pipes, a bulk non-destructive chemical composition analysis was performed on the tongues and shallots, focusing mainly on the ratio between copper and zinc and on the presence of lead. Prompt gamma activation analysis results allowed us to observe for the first time that the ratio between the two main components of the brass alloy changed from Cu:Zn = 3:1 for the old tongues and shallots to Cu:Zn = 2:1 around the middle of the 18th century, which is typical also for the modern alloys offered to the organ builders nowadays. We also discovered that the Pb content in the old historic brass alloy diminished until the middle of 18th century when the brass alloy became mainly Pb free. The non-uniform lead distribution inside one of the shallots obtained from a prompt gamma activation analysis (PGAA) experiment was studied by neutron tomography. It gave us a three-dimensonal (3D) distribution of the lead inclusions inside the shallots. The lead particles are concentrated towards the base of the shallot.

Material Properties for High Temperature Applications.- Thermodynamics of Constitutive Modelling of Damaged Materials.- Developing and Implementing Selected Constitutive Models for Elasto-Plastic-Damage Materials.- Developing and Implementing Constitutive Models for Specific FGM Applications.- Microstructural Analysis and Residual Stress Determination based on Scattering of Neutrons and X-ray Synchrotron Radiation.

The results of a Small-Angle Neutron Scattering (SANS) study are presented, aimed at the investigation of size and morphological characteristics of metallic particles in hot pressed Al2O3/Ni–P nanocomposites. The Ni–P nanoparticles were deposited onto the alumina powder by an electroless plating method and, after drying, the plated powder was sintered at various temperatures (room temperature, 600 °C, 800 °C, 1000 °C) via a hot-pressing method under high pressure (7 GPa). The Ni–P nanoparticle size and fractal dimension were determined, as functions of the sintering temperature. In agreement with previous observations by X-ray diffraction and high-resolution scanning electron microscopy, and as a result of the sintering temperature, the present study shows an increase in the Ni–P particle size. The surface fractal dimension decreases with the increasing sintering temperature, showing the formation of particles with a sharper interface.

The mechanism of mineralized bone matrix deposition was investigated taking advantage of a tissue engineering approach in which bone tissue is formed when porous ceramic scaffold is loaded with bone marrow stromal cells and implanted in vivo. The aim of our study is to point out the interaction between the newly formed mineral crystals and the scaffold imposing the three-dimensional desired architecture to the growing bone. High spatial resolution Small Angle X-ray Scattering measurements obtained using synchrotron radiation and X-ray waveguide as optical element allowed a local structural study at the bone–scaffold interface. Using an original methodology for data analysis, we obtained a two-dimensional microscopic map of the mineralization degree, the collagen presence and the mineral orientation degree around the scaffold pore.

The microstructure and phase composition of the protective Ti48Al2Ag coating produced on Timetal 834 by magnetron sputtering have been examined by scanning and analytical transmission electron microscopy (SEM, TEM). TEM investigations revealed that Ti48Al2Ag coating consists of two sublayers: outer columnar γ-TiAl and amorphous Ti5Al3O2. Energy-dispersive synchrotron radiation diffraction was applied for stress analysis. The results show that there are tensile residual stresses present within the Timetal 834 substrate and compressive residual stresses within the γ-TiAl sublayer.