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In recent years, research into three-dimensional (3-D) scaffolds for tissue engineering has become an important topic. To avoid biological rejection, there are many biocompatible materials being developed for in vitro cultivation of autologous cells for implantation into the human body. The 3-D structures of scaffolds are not easily observed using traditional optical or electron microscopes, which only allow examination of the surfaces of samples or ultra thin films, and often require complicated pre-treating processes. The high-brilliance synchrotron radiation (SR) hard X-ray is an emerging technique to acquire tomography. This study involves the successful reconstruction of 3-D images and the animation of the structure of a collagen scaffold. The images were obtained using synchrotron radiation hard X-ray images, which eliminates the need for embedding and microtoming. SR hard X-ray imaging is a non-destructive technique, which has demonstrated a high spatial resolution and transmission, enabling the morphology of osteoblasts adhered on the inner surfaces of the collagen scaffolds to be captured. It is a convenient facility to obtain 3-D tomography images for biomaterial studies. This is the first study to observe the 3-D structures of collagen scaffolds and aquire detailed images of osteoblast attachment on the scaffold, by utilization of third-generation SR hard X-ray radiography.

In recent years, research into three-dimensional (3-D) scaffolds for tissue engineering has become an important topic. To avoid biological rejection, there are many biocompatible materials being developed for in vitro cultivation of autologous cells for implantation into the human body. The 3-D structures of scaffolds are not easily observed using traditional optical or electron microscopes, which only allow examination of the surfaces of samples or ultra thin films, and often require complicated pre-treating processes. The high-brilliance synchrotron radiation (SR) hard X-ray is an emerging technique to acquire tomography. This study involves the successful reconstruction of 3-D images and the animation of the structure of a collagen scaffold. The images were obtained using synchrotron radiation hard X-ray images, which eliminates the need for embedding and microtoming. SR hard X-ray imaging is a non-destructive technique, which has demonstrated a high spatial resolution and transmission, enabling the morphology of osteoblasts adhered on the inner surfaces of the collagen scaffolds to be captured. It is a convenient facility to obtain 3-D tomography images for biomaterial studies. This is the first study to observe the 3-D structures of collagen scaffolds and aquire detailed images of osteoblast attachment on the scaffold, by utilization of third-generation SR hard X-ray radiography.

We have developed a novel strategy for localized electrochemical deposition (LECD) to improve both the lateral resolution of the process and the porosity of the fabricated high‐aspect‐ratio microstructures. The strategy is based on accurately controlling the motion of the anode. Its implementation is made possible by the use of coherent, synchrotron X‐ray microradiography with high time and lateral resolution, enabling the observation of the copper LECD process in real time. Microradiography reveals a deposition mechanism that differs as a function of the distance between the electrode (anode) and the growing structure (cathode). Specifically, the interplay of migration and diffusion of the metal ions in the baths affects the deposition rate and the characteristics of the fabricated structure. This enables us to optimize the anode motion control and greatly improve the quality of the structure grown.

Can individual cells, including live cells, be imaged using hard x rays? Common wisdom until now required sophisticated staining techniques for this task. We show instead that individual cells and cell details can be detected in culture solution and tissues with no staining and no other contrast-enhancing preparation. The sample examined can be much thicker than for many other microscopy techniques without sacrificing the capability to resolve cells. The key factor in our approach is the use of a coherent synchrotron source and of contrast mechanisms based on the refractive index. The first successful tests were conducted on a variety of cell systems including skin and internal leaf cells, mouse neurons, rabbit fibroblast cells, and human tumor cells.

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Coherent x-rays from synchrotron sources are increasingly used in non-conventional radiological techniques (‘phase-contrast’ radiology). Our experiments demonstrate that by using white (unmonochromatic) radiation and a time-resolving system, it is possible to image microscopic details of moving blood vessels in different live animals without using any contrast agent. The images have excellent contrast plus unprecedented spatial resolution for microangiography (<10 µm). This result is likely to impact many different areas of biological and medical research and of diagnostic radiology.

Abstract: The solubility and diffusion of helium in quartz crystals are investigated as functions of the distribution and density of structural defects. The types of defects in the crystals are identified and their distribution over growth sectors is determined by x-ray diffraction topography and phase radiography with a synchrotron radiation source. The effective solubility and effective diffusion coefficients for helium in quartz are estimated from the experimental data on the amount of helium extracted from samples with different contents of defects. It is revealed that the effective diffusion coefficient of helium depends on the number of dislocations.

The advanced characteristics of synchrotron x-ray sources make it possible to implement radiology with powerful and innovative approaches. We review in simple terms the conceptual background of such approaches, then we present a number of selected examples. The practical tests concern life-sciences specimens as well as materials-science systems.

Multi-photon excitations from thin metallic films on silicon substrates have been observed utilising photoemission electron microscopy. The photoelectrons have been excited by means of high power femtosecond laser pulses with a photon energy below the work function threshold. The strong spatial variations of the non-linear effects became directly visible in electron emission from the adsorbed thin films. Centres of enhanced photoelectron yield, so-called hotspots, were observed on the surfaces of various samples. The multi-photon electron yield of the metallic films (permalloy and lead) depends strongly on the sample topography and the photon polarisation.

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A Nb-V steel’s response to constant true strain rate compression was compared to its behavior when the strain rate varied as during a rolling pass. The constitutive behavior during the two types of tests was found not to differ in a significant manner.

Objective:To assess the discrepancy between laparoscopic and laparotomic scoring methods using the revised American Fertility Society (AFS) classification of endometriosis. Method:In this prospective study, 84 patients with endometriosis were scored twice (laparoscopically and laparotomically) by the same subspecialty-certified reproductive endocrinologist. The magnitude of inter-method variability was reported quantitatively by the S.D. of the differences in scores between the pairs. The differences in the mean endometriosis scores between the two methods were assessed by the paired Student's t-test. P<0.05 was considered as statistically significant. Discrepancy between the two methods in the staging of endometriosis patients was presented by kappa measure of agreement. Result:There was considerable variability in the scores between the two scoring methods by the same observer. Among individual components of the scoring system, the greatest variability occurred in the ovarian endometriosis and cul-de-sac obliteration subscores, with the least variability observed for peritoneum endometriosis. The inter-method variation in score was sufficient to alter the endometriosis staging in 34.5% of patients, including a difference of two stages in 3.6% of patients. The kappa coefficient was 0.49, indicating fair-to-good agreement between the two scoring methods. Conclusion:Inter-method variability between laparoscopic and laparotomic scoring methods was high for ovarian endometriosis subscore using the revised AFS classification of endometriosis. Agreement in endometriosis staging between the two methods was fair to good.

Cystic formation in association with adrenal neuroblastoma may be related to hemorrhage and necrosis of the tumor. We present an unusual case of congenital cystic fetal neuroblastoma of the right adrenal gland detected at 37 weeks' gestation which evolved into a complex echogenic mass 6 weeks after birth. Surgical exploration revealed a 3.5 × 3 × 3 cm right complex adrenal tumor which was resected. The infant did well 10 weeks after tumor resection. Typically adrenal hemorrhage may appear sonographically to be entirely echogenic, of mixed echogenicity, or anechoic when first imaged. Gradually, the texture of the hematoma will evolve and become more cystic and echolucent on follow‐up ultrasound examinations. In contrast, our case of congenital adrenal cystic neuroblastoma became more complex after resolution of the hemorrhagic cyst. This case suggests that adrenal hemorrhage and adrenal cystic neuroblastoma with a hemorrhagic cyst have different sonographic appearances. We suggest that additional imaging and surgical intervention should be considered whenever a cystic suprarenal mass becomes more complex after resolution and demonstrates no significant decrease in size in postnatal examinations. Copyright © 1997 International Society of Ultrasound in Obstetrics and Gynecology

Recently, in-vitro maturation (IVM) of immature human oocytes recovered from non-stimulated follicles has been applied in the treatment of infertility. However, in previous reports, very few embryos cultured in conventional medium have reached the expanded blastocyst stage following in-vitro maturation and fertilization (IVM/IVF). The objective of this study was to investigate whether the developmental competence of human embryos following IVM/IVF could be enhanced by the use of a human ampullary cell co-culture system. Immature human oocytes were aspirated from small follicles at Caesarean section and then cultured in medium containing human menopausal gonadotrophin for 36 to 48 h, followed by insemination. Zygotes were randomly cultured either in conventional culture medium alone or in the co-culture system. Of 48 embryos cultured in conventional medium alone, all arrested at the 2-16-cell stage on day 3 after insemination. Of 46 embryos cultured in the co-culture system, 26 embryos (56.5%) arrested at the 2-16-cell stage. Six embryos (13%) developed to the morula stage. Fourteen embryos (30.4%) developed to expanded blastocysts and two blastocysts were hatching on day 7 after insemination. We conclude that co-culture significantly enhances the development of blastocysts in embryos resulting from IVM/IVF.

Since its invention in 1930, Zernike phase contrast has been a pillar in optical microscopy and more recently in x-ray microscopy, in particular for low-absorption-contrast biological specimens. We experimentally demonstrate that hard-x-ray Zernike microscopy now reaches a lateral resolution below 30?nm while strongly enhancing the contrast, thus opening many new research opportunities in biomedicine and materials science.

Using synchrotron-radiation core-level photoemission, we found that the formation of the YBaCuO-Pb interface is notunreactive. A reacted PbO-like intralayer is formed for substrate temperatures down to 40−50 K. The intralayer is very thin, and automatically results in the formation of an SIS structure.

Real-time X-ray microscopy was used to study the influence of hydrogen-bubble formation on the morphology of ramified zinc electrodeposit. The experimental results show that when intense hydrogen bubbling occurs at high potential, the morphology of the ramified zinc deposit changes from dense-branching to fern-shaped dendrite. The fern-shaped dendrite results in part from the constricted growth due to hydrogen bubbles but also from the highly concentrated electric field. The fern-shaped dendrite morphology was observed during the early stages of electroplating for both the potentiostatic and galvanostatic modes; however, the deposit plated in the galvanostatic mode densified via lateral growth during the later plating stages. This indicates that potentiostatic plating for which the hydrogen-bubble formation steadily occurs throughout the electrodeposition process is better than galvanostatic plating for fabricating fern-shaped deposits, which are ideal electrodes for Zn–air batteries due to the relatively large specific area.

We describe a technique to fabricate three-dimensional (3D), freestanding metallic micro hollow tubes by template-free localized electrochemical deposition. The features of the grown structure are controlled by the field strength distribution in its proximity that depends on the applied voltage and the microelectrode-structure distance (L). The formation of micro hollow tubes is induced by the enhanced electric field at the microelectrode rim for small Lvalues (a few micrometers or less) and high applied voltages.

The elemental magnetic moments of Co and Cr in CoCrPt films were investigated using xray magnetic circular dichroism (XMCD). The spin and orbital moments of Co was calculated using the sum rules; it was found that the magnetic moment of Co in CoCrPt films was dominated by spin moment contribution. The total magnetic moment of Co was found to be lower than that of bulk Co. Further, the Cr moment was aligned anti-ferromagnetically with respect to Co, resulting in a decrease of saturation magnetization (Ms) in CoCrPt films.

The capability to perform absorption spectroscopy with hard x-rays was added to the synchrotron imaging Spectromicroscopy technique. We present several successful test cases. First, the EXAFS (extended x-ray absorption fine structure) analysis was implemented in areas as small as few µm2for transition-metal K edge absorption spectra. The corresponding structural information was complemented by chemical information from the near-edge region. Specifically, in the case of a cross-sectional cut steel different Fe oxidation states were found at different depths. Tests on a PVD grown TiN film revealed areas with oxidized Ti. Overall, these tests demonstrate the feasibility of combining structural and chemicals analysis with hard-x-ray absorption and high lateral resolution.