Publications by authors named "Honglan Xie"

19 Publications

  • Page 1 of 1

Sensitive imaging of intact microvessels with synchrotron radiation.

IUCrJ 2020 Sep 11;7(Pt 5):793-802. Epub 2020 Jul 11.

Shanghai Synchrotron Radiation Facility/Zhangjiang Laboratory, Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai 201204, People's Republic of China.

Early stages of diseases, including stroke, hypertension, angiogenesis of tumours, spinal cord injuries, ., are closely associated with the lesions of microvasculature. Rodent models of human vascular diseases are extensively used for the preclinical investigation of the disease evolution and therapy with synchrotron radiation. Therefore, non-invasive and X-ray imaging with high sensitivity and clarity is desperately needed to visualize the microvessels in live-animal models. Contrast agent is essential for the X-ray imaging of vessels and angiomatous tissue. Because of the non-rigid motion of adjacent tissues, the short circulation time and the intermittent flow of contrast agents in vessels, it is a great challenge for the traditional X-ray imaging methods to achieve well defined images of microvessels . In this article, move contrast X-ray imaging (MCXI) based on high-brightness synchrotron radiation is developed to overcome the intrinsic defects in conventional methods. Experiments with live rodents demonstrate the practicability of the MCXI method for sensitive and intact imaging of microvessels .
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http://dx.doi.org/10.1107/S2052252520008234DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7467167PMC
September 2020

High-efficiency fast X-ray imaging detector development at SSRF.

J Synchrotron Radiat 2019 Sep 23;26(Pt 5):1631-1637. Epub 2019 Aug 23.

Shanghai Synchrotron Radiation Facility (SSRF), Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai, People's Republic of China.

Indirect X-ray imaging detectors consisting of scintillator screens, long-working-distance microscope lenses and scientific high-speed complementary metal-oxide semiconductor (CMOS) cameras are usually used to realize fast X-ray imaging with white-beam synchrotron radiation. However, the detector efficiency is limited by the coupling efficiency of the long-working-distance microscope lenses, which is only about 5%. A long-working-distance microscope lenses system with a large numerical aperture (NA) is designed to increase the coupling efficiency. It offers an NA of 0.5 at 8× magnification. The Mitutoyo long-working-distance microscope lenses system offers an NA of 0.21 at 7.5× magnification. Compared with the Mitutoyo system, the developed long-working-distance microscope lenses system offers about twice the NA and four times the coupling efficiency. In the indirect X-ray imaging detector, a 50 µm-thick LuAG:Ce scintillator matching with the NA, and a high-speed visible-light CMOS FastCAM SAZ Photron camera are used. Test results show that the detector realized fast X-ray imaging with a frame rate of 100000 frames s and fast X-ray microtomography with a temporal sampling rate up to 25 Hz (25 tomograms s).
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http://dx.doi.org/10.1107/S1600577519010075DOI Listing
September 2019

Structural and topological nature of plasticity in sheared granular materials.

Nat Commun 2018 07 25;9(1):2911. Epub 2018 Jul 25.

School of Physics and Astronomy, Shanghai Jiao Tong University, 800 Dong Chuan Road, Shanghai, 200240, China.

Upon mechanical loading, granular materials yield and undergo plastic deformation. The nature of plastic deformation is essential for the development of the macroscopic constitutive models and the understanding of shear band formation. However, we still do not fully understand the microscopic nature of plastic deformation in disordered granular materials. Here we used synchrotron X-ray tomography technique to track the structural evolutions of three-dimensional granular materials under shear. We establish that highly distorted coplanar tetrahedra are the structural defects responsible for microscopic plasticity in disordered granular packings. The elementary plastic events occur through flip events which correspond to a neighbor switching process among these coplanar tetrahedra (or equivalently as the rotation motion of 4-ring disclinations). These events are discrete in space and possess specific orientations with the principal stress direction.
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http://dx.doi.org/10.1038/s41467-018-05329-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6060108PMC
July 2018

Improving the efficiency of small-angle x-ray scattering computed tomography using the OSEM algorithm.

Appl Opt 2017 Oct;56(30):8326-8334

Small-angle x-ray scattering computed tomography (SAXS-CT) is a nondestructive method for the nanostructure analysis of heterogeneous materials. However, the limits of a long data acquisition time and vast amounts of data prevent SAXS-CT from becoming a routine experimental method in the applications of synchrotron radiation. In this study, the ordered subsets expectation maximization (OSEM) algorithm is introduced to improve the efficiency of SAXS-CT. To demonstrate the practicability of this method, a systematic simulation and experiments were carried out. The simulation results on a numerical phantom show that the OSEM-based SAXS-CT can effectively eliminate streaking artifacts and improve the efficiency of data acquisition by at least 3 times compared with the filter backprojection algorithm. By compromising the reconstruction speed and image quality, the optimal reconstruction parameters are also given for the image reconstruction in the OSEM-based SAXS-CT experiments. An experiment on a bamboo sample verified the validity of the proposed method with limited projection data. A further experiment on polyethylene demonstrated that the OSEM-based SAXS-CT is able to reveal the local nanoscale information about the crystalline structure and distributional difference inside the sample. In conclusion, the OSEM-based SAXS-CT can significantly improve experimental efficiency, which may promote SAXS-CT becoming a conventional method.
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http://dx.doi.org/10.1364/AO.56.008326DOI Listing
October 2017

Monochromatic-beam-based dynamic X-ray microtomography based on OSEM-TV algorithm.

J Xray Sci Technol 2017 ;25(6):1007-1017

Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai, China.

Monochromatic-beam-based dynamic X-ray computed microtomography (CT) was developed to observe evolution of microstructure inside samples. However, the low flux density results in low efficiency in data collection. To increase efficiency, reducing the number of projections should be a practical solution. However, it has disadvantages of low image reconstruction quality using the traditional filtered back projection (FBP) algorithm. In this study, an iterative reconstruction method using an ordered subset expectation maximization-total variation (OSEM-TV) algorithm was employed to address and solve this problem. The simulated results demonstrated that normalized mean square error of the image slices reconstructed by the OSEM-TV algorithm was about 1/4 of that by FBP. Experimental results also demonstrated that the density resolution of OSEM-TV was high enough to resolve different materials with the number of projections less than 100. As a result, with the introduction of OSEM-TV, the monochromatic-beam-based dynamic X-ray microtomography is potentially practicable for the quantitative and non-destructive analysis to the evolution of microstructure with acceptable efficiency in data collection and reconstructed image quality.
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http://dx.doi.org/10.3233/XST-17279DOI Listing
August 2018

Visualization and Pathological Characteristics of Hepatic Alveolar Echinococcosis with Synchrotron-based X-ray Phase Sensitive Micro-tomography.

Sci Rep 2016 11 29;6:38085. Epub 2016 Nov 29.

State Key Laboratory Incubation Base of Xinjiang Major Diseases Research, FirstAffiliated Hospital, Xinjiang Medical University, Urumchi 830054, China.

Propagation-based phase-contrast computed tomography (PPCT) utilizes highly sensitive phase-contrast technology applied to X-ray micro-tomography, especially with the extensive use of synchrotron radiation (SR). Performing phase retrieval (PR) on the acquired angular projections can enhance image contrast and enable quantitative imaging. We employed the combination of SR-PPCT and PR for the histopathological evaluation of hepatic alveolar echinococcosis (HAE) disease and demonstrated the validity and superiority of PR-based SR-PPCT. A high-resolution angular projection data set of a human postoperative specimen of HAE disease was acquired, which was processed by graded ethanol concentration fixation (GECF). The reconstructed images from both approaches, with the projection data directly used and preprocessed by PR for tomographic reconstruction, were compared in terms of the tissue contrast-to-noise ratio and density spatial resolution. The PR-based SR-PPCT was selected for microscale measurement and the 3D visualization of HAE disease. Our experimental results demonstrated that the PR-based SR-PPCT technique is greatly suitable for the discrimination of pathological tissues and the characterization of HAE. In addition, this new technique is superior to conventional hospital CT and microscopy for the three-dimensional, non-destructive microscale measurement of HAE. This PR-based SR-PPCT technique has great potential for in situmicroscale histopathological analysis and diagnosis, especially for applications involving soft tissues and organs.
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http://dx.doi.org/10.1038/srep38085DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5126691PMC
November 2016

Fourier-Transform Ghost Imaging with Hard X Rays.

Phys Rev Lett 2016 Sep 7;117(11):113901. Epub 2016 Sep 7.

University of Science and Technology of China, Hefei 230026, China.

Knowledge gained through x-ray crystallography fostered structural determination of materials and greatly facilitated the development of modern science and technology in the past century. However, it is only applied to crystalline structures and cannot resolve noncrystalline materials. Here we demonstrate a novel lensless Fourier-transform ghost imaging method with pseudothermal hard x rays that extends x-ray crystallography to noncrystalline samples. By measuring the second-order intensity correlation function of the light, Fourier-transform diffraction pattern of a complex amplitude sample is achieved at the Fresnel region in our experiment and the amplitude and phase distributions of the sample in the spatial domain are retrieved successfully. For the first time, ghost imaging is experimentally realized with x rays. Since a highly coherent x-ray source is not required, the method can be implemented with laboratory x-ray sources and it also provides a potential solution for lensless diffraction imaging with fermions, such as neutrons and electrons where intensive coherent sources usually are not available.
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http://dx.doi.org/10.1103/PhysRevLett.117.113901DOI Listing
September 2016

Anisotropic shrinkage of insect air sacs revealed in vivo by X-ray microtomography.

Sci Rep 2016 09 1;6:32380. Epub 2016 Sep 1.

Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201204, China.

Air sacs are thought to be the bellows for insect respiration. However, their exact mechanism of action as a bellows remains unclear. A direct way to investigate this problem is in vivo observation of the changes in their three-dimensional structures. Therefore, four-dimensional X-ray phase contrast microtomography is employed to solve this puzzle. Quantitative analysis of three-dimensional image series reveals that the compression of the air sac during respiration in bell crickets exhibits obvious anisotropic characteristics both longitudinally and transversely. Volumetric changes of the tracheal trunks in the prothorax further strengthen the evidence of this finding. As a result, we conclude that the shrinkage and expansion of the insect air sac is anisotropic, contrary to the hypothesis of isotropy, thereby providing new knowledge for further research on the insect respiratory system.
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http://dx.doi.org/10.1038/srep32380DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5007674PMC
September 2016

X-ray propagation-based equally sloped tomography for mouse brain.

J Xray Sci Technol 2016 ;24(1):79-86

Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai, China.

Background: The outstanding functional importance of the brain implies a strong need for brain imaging modalities. However, the current imaging approaches that target the brain in rodents remain suboptimal.

Objective And Methods: In this paper, X-ray propagation-based phase contrast imaging combined with equally sloped tomography (PPCI-EST) was employed to nondestructively investigate the mouse brain.

Results: The grey and white matters, which have extremely small differences in electron density, were clearly discriminated. The fine structures, including the corpus callosum (cc), the optic chiasma (ox) and the caudate putamen (CPu), were revealed. Compared to the filtered back projection reconstruction, the PPCI-EST significantly reduce projection number while maintaining sufficient image quality.

Conclusions: It could be a potential tool for fast and low-dose phase-contrast imaging to biomedical specimens.
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http://dx.doi.org/10.3233/XST-160533DOI Listing
December 2016

3D elemental sensitive imaging by full-field XFCT.

Analyst 2015 May 2;140(10):3521-5. Epub 2015 Apr 2.

Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Zhangheng Road 239, 201204 Shanghai, China.

X-ray fluorescence computed tomography (XFCT) is a stimulated emission tomography modality that maps the three-dimensional (3D) distribution of elements. Generally, XFCT is done by scanning a pencil-beam across the sample. This paper presents a feasibility study of full-field XFCT (FF-XFCT) for 3D elemental imaging. The FF-XFCT consists of a pinhole collimator and X-ray imaging detector with no energy resolution. A prototype imaging system was set up at the Shanghai Synchrotron Radiation Facility (SSRF) for imaging the phantom. The first FF-XFCT experimental results are presented. The cadmium (Cd) and iodine (I) distributions were reconstructed. The results demonstrate FF-XFCT is fit for 3D elemental imaging and the sensitivity of FF-XFCT is higher than a conventional CT system.
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http://dx.doi.org/10.1039/c4an02401jDOI Listing
May 2015

Mouse coronary angiography in vivo using synchrotron radiation.

Biomed Mater Eng 2014 ;24(1):1341-9

Department of Biomedical Engineering, School of Medicine, Shanghai Jiao Tong University, No.280, South Chongqing RD, Shanghai, China.

Purpose: To establish a method for mouse coronary angiography in vivo using synchrotron radiation, which is essential for physiological and pathological research on coronary diseases.

Methods: 1) The imaging parameters (e.g., photon energy, spatial resolution of the detector, and injection rate of contrast agent) optimal for the quality of acquired images in a simulation were determined. 2) Through animal experiments, the effectiveness of these optimal parameters and the repeatability of in vivo coronary angiography were verified. 3) An algorithm for background subtraction and contrast enhancement was designed and employed to compensate for the effects of interference and the effective information extracted used for diagnosing coronary disease.

Results And Conclusions: An optimal set of the imaging parameters was finally determined: photon energy of 33-34 keV, detector's spatial resolution of 30 μm or higher, image capture rate of 20 f/s or more, concentration of lopamidol solution of 75% as contrast agent and a pulse injection of contrast agent at a high rate.
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http://dx.doi.org/10.3233/BME-130937DOI Listing
June 2014

Phase retrieval for hard X-ray computed tomography of samples with hybrid compositions.

Chin Opt Lett 2012 Dec;10(12):121101

Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201204, China.

X-ray tomography of samples containing both weakly and strongly absorbing materials are necessary in material and biomedical imaging. Extending the validity of the phase-attenuation duality (PAD) method, the propagation-based phase-contrast computed tomography (PPCT) of a sample with hybrid compositions of both the light and dense components with 60 keV of synchrotron radiation is investigated. The experimental results show that the PAD-based PPCT is effective in imaging both the weakly and strongly absorbing components simultaneously. Compared with the direct PPCT technique, the PAD-based PPCT technique demonstrates its excellent capability in material discrimination and characterization. In addition, the PAD-based PPCT exhibits a striking performance on the image contrast enhancement and noise suppression. Therefore, this technique is useful for material and biomedical imaging applications, especially when the radiation dose involved imposes a serious constraint.
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http://dx.doi.org/10.3788/COL201210.121101DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3699885PMC
December 2012

Real-time imaging of mouse lenticulostriate artery following brain ischemia.

Front Biosci (Elite Ed) 2013 Jan 1;5:517-24. Epub 2013 Jan 1.

Neuroscience and Neuroengineering Research Center, Med-X Research Institute, School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China.

Detection of microvascular changes in experimental stroke models is limited by current technologies. Using state-of-the-art synchrotron radiation (SR), we explored the feasibility of detecting the normal morphological variations of lenticulostriate arteries (LSAs) and the changes to LSAs following middle cerebral artery occlusion (MCAO). Cerebral microvessels of ICR mice were imaged with synchrotron radiation microangiography using nonionic iodine and barium sulfate as contrast agents. Using SR we reproducibly observed the detailed cerebral microvasculature of LSAs arising from the origin of middle cerebral artery (MCA) with a resolution of approximately 5 micrometers, at least a 20-fold greater resolution compared to CT or MRI imaging. Notably, SR microangiography was able to reveal ischemia/reperfusion induced leakage in the lenticulostriate artery territory. To our knowledge this is the first time that the three-dimensional morphology of LSAs and real time visualization of LSA hemorrhage have been characterized in live mice. This work demonstrates that SR microangiography can provide a unique tool for furthering experimental stroke research to examine the efficacy of neuroprotective therapies on parameters such as angiogenesis and vascular integrity.
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http://dx.doi.org/10.2741/e633DOI Listing
January 2013

X-ray phase contrast imaging of cell isolation with super-paramagnetic microbeads.

PLoS One 2012 24;7(9):e45597. Epub 2012 Sep 24.

Department of Radiology, Rui Jin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, People's Republic of China.

Super-paramagnetic microbeads are widely used for cell isolation. Evaluation of the binding affinity of microbeads to cells using optical microscopy has been limited by its small scope. Here, magnetic property of microbeads was first investigated by using synchrotron radiation (SR) in-line x-ray phase contrast imaging (PCI). The cell line mouse LLC (Lewis lung carcinoma) was selected for cell adhesion studies. Targeted microbeads were prepared by attaching anti-VEGFR2 (vascular endothelial growth factor receptor-2) antibody to the shell of the microbeads. The bound microbeads were found to better adhere to LLC cells than unbound ones. PCI dynamically and clearly showed the magnetization and demagnetization of microbeads in PE-50 tube. The cells incubated with different types of microbeads were imaged by PCI, which provided clear and real-time visualization of the cell isolation. Therefore, PCI might be considered as a novel and efficient tool for further cell isolation studies.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0045597PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3454406PMC
March 2013

Anti-VEGFR2-conjugated PLGA microspheres as an x-ray phase contrast agent for assessing the VEGFR2 expression.

Phys Med Biol 2012 May 26;57(10):3051-63. Epub 2012 Apr 26.

Department of Radiology, Rui Jin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, People's Republic of China.

The primary goal of this study was to evaluate the feasibility of using anti-vascular endothelial growth factor receptor 2 (VEGFR2)-conjugated poly(lactic-co-glycolic acid) (PLGA) microspheres as an x-ray phase contrast agent to assess the VEGFR2 expression in cell cultures. The cell lines, mouse LLC (Lewis lung carcinoma) and HUVEC (human umbilical vein endothelial cell), were selected for cell adhesion studies. The bound PLGA microspheres were found to better adhere to LLC cells or HUVECs than unbound ones. Absorption and phase contrast images of PLGA microspheres were acquired and compared in vitro. Phase contrast imaging (PCI) greatly improves the detection of the microspheres as compared to absorption contrast imaging. The cells incubated with PLGA microspheres were imaged by PCI, which provided clear 3D visualization of the beads, indicating the feasibility of using PLGA microspheres as a contrast agent for phase contrast CT. In addition, the microspheres could be clearly distinguished from the wall of the vessel on phase contrast CT images. Therefore, the approach holds promise for assessing the VEGFR2 expression on endothelial cells of tumor-associated vessels. We conclude that PLGA microsphere-based PCI of the VEGFR2 expression might be a novel, promising biomarker for future studies of tumor angiogenesis.
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http://dx.doi.org/10.1088/0031-9155/57/10/3051DOI Listing
May 2012

Bag-of-features based medical image retrieval via multiple assignment and visual words weighting.

IEEE Trans Med Imaging 2011 Nov 18;30(11):1996-2011. Epub 2011 Aug 18.

Shanghai Institute of Applied Physics, Chinese Academy of Science.

Bag-of-features based approaches have become prominent for image retrieval and image classification tasks in the past decade. Such methods represent an image as a collection of local features, such as image patches and key points with scale invariant feature transform (SIFT) descriptors. To improve the bag-of-features methods, we first model the assignments of local descriptors as contribution functions, and then propose a novel multiple assignment strategy. Assuming the local features can be reconstructed by their neighboring visual words in a vocabulary, reconstruction weights can be solved by quadratic programming. The weights are then used to build contribution functions, resulting in a novel assignment method, called quadratic programming (QP) assignment. We further propose a novel visual word weighting method. The discriminative power of each visual word is analyzed by the sub-similarity function in the bin that corresponds to the visual word. Each sub-similarity function is then treated as a weak classifier. A strong classifier is learned by boosting methods that combine those weak classifiers. The weighting factors of the visual words are learned accordingly. We evaluate the proposed methods on medical image retrieval tasks. The methods are tested on three well-known data sets, i.e., the ImageCLEFmed data set, the 304 CT Set, and the basal-cell carcinoma image set. Experimental results demonstrate that the proposed QP assignment outperforms the traditional nearest neighbor assignment, the multiple assignment, and the soft assignment, whereas the proposed boosting based weighting strategy outperforms the state-of-the-art weighting methods, such as the term frequency weights and the term frequency-inverse document frequency weights.
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http://dx.doi.org/10.1109/TMI.2011.2161673DOI Listing
November 2011

Microbubble-based synchrotron radiation phase contrast imaging: basic study and angiography applications.

Phys Med Biol 2011 Jun 23;56(12):3503-12. Epub 2011 May 23.

Department of Radiology, Ruijin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200025, People's Republic of China.

The purpose of the study was to evaluate the feasibility of microbubbles as phase contrast imaging (PCI) agents for angiography applications. The hypothesis was that the introduction of microbubbles into tissue produces a significant change in the refractive index and highlights the lumen of the vessel in PCI. The absorption and phase contrast images of commercially available microbubbles were obtained and compared in vitro. A further increase in contrast was observed in PCI. Microbubbles highlighted the lumen of the renal microvessels, acting as a positive contrast medium in ex vivo imaging. In addition, home-made microbubbles with larger diameters were introduced for image contrast enhancement in living tumor-bearing mice, demonstrating the feasibility of microbubble-based x-ray phase-contrast imaging for tumor vasculature in vivo.
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http://dx.doi.org/10.1088/0031-9155/56/12/004DOI Listing
June 2011

Detection of microvasculature in rat hind limb using synchrotron radiation.

J Surg Res 2010 Nov 3;164(1):e193-9. Epub 2010 Jun 3.

Department of Vascular Surgery, Zhongshan Hospital, Fudan University, Shanghai, China.

Background: New X-ray microangiography and third-generation synchrotron radiation-based micro-computed tomography have opened new perspectives for microvascular imaging of extremity. Here we aimed to visualize deep-level microvascular structure in rat hind limb by microangiographic technique, and compare images with those by conventional method.

Materials And Methods: A total of 10 Sprague Dawley rats were used for in vivo and ex vivo study (five rats/group). Microangiography in vivo and ex vivo was performed and images were compared with those by conventional method. Synchrotron radiation-based micro-computed tomography (SRμCT) was also performed to reveal three-dimensional (3D) morphology of the blood vessel in rat hind limb.

Results: By microangiographic technique, blood vessels in the rat limb could be clearly depicted with the minimum visualized blood vessel about 9 μm in diameter, and higher angiographic scores were achieved than those by conventional X-ray. In addition, the vascular network could be defined and analyzed at the micrometer scale from the 3D renderings of limb vessel as shown by SRμCT.

Conclusions: Synchrotron radiation-based microangiography and SRμCT thus provided a practical and effective means to observe the microvasculature of limbs, which might be useful in assessment of angiogenesis in lower limbs.
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http://dx.doi.org/10.1016/j.jss.2010.05.015DOI Listing
November 2010

Evolution of dendrite morphology of a binary alloy under an applied electric current: an in situ observation.

Phys Rev E Stat Nonlin Soft Matter Phys 2010 Apr 29;81(4 Pt 1):042601. Epub 2010 Apr 29.

School of Materials Science and Engineering, Dalian University of Technology, Dalian 116023, China.

Synchrotron radiation imaging technique was used to in situ observe the dendrite growth of a solidifying Sn-Bi binary alloy under a direct current (dc) electric field. By applying a dc (7-32 A/cm2), the dendrite branching was suppressed, the dendrite tip was modified to be round or flat, and no tertiary dendrite was found. With increasing dc density, the dendrite morphology was changed from columnar dendritic to equiaxed cellular to equiaxed dendritic. In particular, the primary dendrite branched following a tip-split manner in a higher intensity dc. The influence of dc on the evolution of dendrite morphology was discussed.
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http://dx.doi.org/10.1103/PhysRevE.81.042601DOI Listing
April 2010