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Sample records for alter three-dimensional collagen

  1. Scanning electron microscopic observation: three-dimensional architecture of the collagen in hepatic fibrosis rats

    Institute of Scientific and Technical Information of China (English)

    WANG Xiao-hong; ZHAO Jing; ZHANG Wei-guang; ZHANG Li-ying; MA Rui-qiong; WANG Li-qin; ZHANG Shu-yong; TIAN Long

    2007-01-01

    Background In the process of hepatic fibrosis, the accumulation of collagen fibers is strongly related to the hepatic function. The aim of this study was to investigate the three-dimensional architecture of the collagen network in the liver of rats with hepatic fibrosis.Methods Healthy adult male Wistar rats (n=32) were randomly divided into a control group (n=16) and a hepatic fibrosis group (n=16). In the control group, the rats were treated with peanut oil while the rats in hepatic fibrosis group were treated for 10 weeks with 60% CCl4 diluted in peanut oil. The quantity of collagen fibers was detected by Western blotting; distribution of the collagen was detected by sirius red staining and polarized microscope; the three-dimensional architecture of collagen in the liver was observed under the scanning electron microscope after fixed tissues were treated with cell-maceration using NaOH. Statistical analysis was performed using the u test.Results The quantity of collagen fibers increased significantly in the hepatic fibrosis group. With the aggravation of hepatic fibrosis, collagen fibers gradually accumulated. They interlaced the reticulation compartment and formed a round or ellipse liver tissue conglomeration like a grape framework that was disparate and wrapped up the normal liver Iobule.The deposition of collagen fibers was obvious in adjacent hepatic parenchyma, especially around the portal tracts.Conclusion Our experiment showed the collagen proliferation and displays clearly the three-dimensional architecture of collagen fibers in rat liver with hepatic fibrosis by scanning electron microscope. It can provide a morphological foundation for the mechanisms of changed haemodynamics and portal hypertension in hepatic fibrosis.

  2. Quantification of three-dimensional cell-mediated collagen remodeling using graph theory.

    Directory of Open Access Journals (Sweden)

    Cemal Cagatay Bilgin

    Full Text Available BACKGROUND: Cell cooperation is a critical event during tissue development. We present the first precise metrics to quantify the interaction between mesenchymal stem cells (MSCs and extra cellular matrix (ECM. In particular, we describe cooperative collagen alignment process with respect to the spatio-temporal organization and function of mesenchymal stem cells in three dimensions. METHODOLOGY/PRINCIPAL FINDINGS: We defined two precise metrics: Collagen Alignment Index and Cell Dissatisfaction Level, for quantitatively tracking type I collagen and fibrillogenesis remodeling by mesenchymal stem cells over time. Computation of these metrics was based on graph theory and vector calculus. The cells and their three dimensional type I collagen microenvironment were modeled by three dimensional cell-graphs and collagen fiber organization was calculated from gradient vectors. With the enhancement of mesenchymal stem cell differentiation, acceleration through different phases was quantitatively demonstrated. The phases were clustered in a statistically significant manner based on collagen organization, with late phases of remodeling by untreated cells clustering strongly with early phases of remodeling by differentiating cells. The experiments were repeated three times to conclude that the metrics could successfully identify critical phases of collagen remodeling that were dependent upon cooperativity within the cell population. CONCLUSIONS/SIGNIFICANCE: Definition of early metrics that are able to predict long-term functionality by linking engineered tissue structure to function is an important step toward optimizing biomaterials for the purposes of regenerative medicine.

  3. Growth and differentiation of neural stem cells in a three-dimensional collagen gel scaffold

    Institute of Scientific and Technical Information of China (English)

    Fei Huang; Qiang Shen; Jitong Zhao

    2013-01-01

    Collagen protein is an ideal scaffold material for the transplantation of neural stem cells. In this study, rat neural stem cells were seeded into a three-dimensional collagen gel scaffold, with suspension cultured neural stem cells being used as a control group. Neural stem cells, which were cultured in medium containing epidermal growth factor and basic fibroblast growth factor, actively expanded and formed neurospheres in both culture groups. In serum-free medium conditions, the processes extended from neurospheres in the collagen gel group were much longer than those in the suspension culture group. Immunofluorescence staining showed that neurospheres cultured in collagen gels were stained positive for nestin and differentiated cells were stained positive for the neuronal marker βIII-tubulin, the astrocytic marker glial fibrillary acidic protein and the oligodendrocytic marker 2',3'-cyclic nucleotide 3'-phosphodiesterase. Compared with neurospheres cultured in suspension, the differentiation potential of neural stem cells cultured in collagen gels increased, with the formation of neurons at an early stage. Our results show that the three-dimensional collagen gel culture system is superior to suspension culture in the proliferation, differentiation and process outgrowth of neural stem cells.

  4. [Research Progress of Collagen-based Three-dimensional Porous Scaffolds Used in Skin Tissue Engineering].

    Science.gov (United States)

    Zhang, Jing; Tang, Qiwei; Zhou, Aimei; Yang, Shulin

    2015-08-01

    Collagen is a kind of natural biomedical material and collagen based three-dimensional porous scaffolds have been widely used in skin tissue engineering. However, these scaffolds do not meet the requirements for artificial skin substitutes in terms of their poor mechanical properties, short supply, and rejection in the bodies. All of these factors limit their further application in skin tissue engineering. A variety of methods have been chosen to meliorate the situation, such as cross linking and blending other substance for improving mechanical properties. The highly biomimetic scaffolds either in structure or in function can be prepared through culturing cells and loading growth factors. To avoid the drawbacks of unsafety attributing to animals, investigators have fixed their eyes on the recombinant collagen. This paper reviews the the progress of research and application of collagen-based 3-dimensional porous scaffolds in skin tissue engineering. PMID:26710471

  5. In situ collagen assembly for integrating microfabricated three-dimensional cell-seeded matrices

    Science.gov (United States)

    Gillette, Brian M.; Jensen, Jacob A.; Tang, Beixian; Yang, Genevieve J.; Bazargan-Lari, Ardalan; Zhong, Ming; Sia, Samuel K.

    2008-08-01

    Microscale fabrication of three-dimensional (3D) extracellular matrices (ECMs) can be used to mimic the often inhomogeneous and anisotropic properties of native tissues and to construct in vitro cellular microenvironments. Cellular contraction of fibrous natural ECMs (such as fibrin and collagen I) can detach matrices from their surroundings and destroy intended geometry. Here, we demonstrate in situ collagen fibre assembly (the nucleation and growth of new collagen fibres from preformed collagen fibres at an interface) to anchor together multiple phases of cell-seeded 3D hydrogel-based matrices against cellular contractile forces. We apply this technique to stably interface multiple microfabricated 3D natural matrices (containing collagen I, Matrigel, fibrin or alginate); each phase can be seeded with cells and designed to permit cell spreading. With collagen-fibre-mediated interfacing, microfabricated 3D matrices maintain stable interfaces (the individual phases do not separate from each other) over long-term culture (at least 3weeks) and support spatially restricted development of multicellular structures within designed patterns. The technique enables construction of well-defined and stable patterns of a variety of 3D ECMs formed by diverse mechanisms (including temperature-, ion- and enzyme-mediated crosslinking), and presents a simple approach to interface multiple 3D matrices for biological studies and tissue engineering.

  6. Three-dimensional printed miniaturized spectral system for collagen fluorescence lifetime measurements

    Science.gov (United States)

    Zou, Luwei; Koslakiewicz, Ronald; Mahmoud, Mohamad; Fahs, Mehdi; Liu, Rui; Lo, Joe Fujiou

    2016-07-01

    Various types of collagens, e.g., type I and III, represent the main load-bearing components in biological tissues. Their composition changes during processes such as wound healing and fibrosis. When excited by ultraviolet light, collagens exhibit autofluorescence distinguishable by their unique fluorescent lifetimes across a range of emission wavelengths. Here, we designed a miniaturized spectral-lifetime detection system as a noninvasive probe for monitoring tissue collagen compositions. A sine-modulated LED illumination was applied to enable frequency domain fluorescence lifetime measurements under three wavelength bands, separated via a series of longpass dichroics at 387, 409, and 435 nm. We employed a lithography-based three-dimensional (3-D) printer with <50 μm resolution to create a custom designed optomechanics in a handheld form factor. We examined the characteristics of the optomechanics with finite element modeling to simulate the effect of thermal (from LED) and mechanical (from handling) strain on the optical system. The geometry was further optimized with ray tracing to form the final 3-D printed structure. Using this device, the phase shift and demodulation of collagen types were measured, where the separate spectral bands enhanced the differentiation of their lifetimes. This system represents a low cost, handheld probe for clinical tissue monitoring applications.

  7. The Three-Dimensional Collagen Scaffold Improves the Stemness of Rat Bone Marrow Mesenchymal Stem Cells

    Institute of Scientific and Technical Information of China (English)

    Sufang Han; Yannan Zhao; Zhifeng Xiao; Jin Han; Bing Chen; Lei Chen; Jianwu Dai

    2012-01-01

    Mesenchymal stem cells (MSCs) show the great promise for the treatment of a variety of diseases because of their self-renewal and multipotential abilities.MSCs are generally cultured on two-dimensional (2D) substrate in vitro.There are indications that they may simultaneously lose their stemness and multipotentiality as the result of prolonged 2D culture.In this study,we used three-dimensional (3D) collagen scaffolds as rat MSCs carrier and compared the properties of MSCs on 3D collagen scaffolds with monolayer cultured MSCs.The results demonstrated that collagen scaffolds were suitable for rat MSCs adherence and proliferation.More importantly,compared to MSCs under 2D culture,3D MSCs significantly maintained higher expression levels of stemness genes (Oct4,Sox2,Rex-1 and Nanog),yielded high frequencies of colony-forming units-fibroblastic (CFU-F) and showed enhanced osteogenic and adipogenic differentiation efficiency upon induction.Thus,3D collagen scaffolds may be beneficial for expanding rat MSCs while maintaining the stem cell properties in vitro.

  8. Additive manufacturing of collagen scaffolds by three-dimensional plotting of highly viscous dispersions.

    Science.gov (United States)

    Lode, Anja; Meyer, Michael; Brüggemeier, Sophie; Paul, Birgit; Baltzer, Hagen; Schröpfer, Michaela; Winkelmann, Claudia; Sonntag, Frank; Gelinsky, Michael

    2016-03-01

    Additive manufacturing (AM) allows the free form fabrication of three-dimensional (3D) structures with distinct external geometry, fitting into a patient-specific defect, and defined internal pore architecture. However, fabrication of predesigned collagen scaffolds using AM-based technologies is challenging due to the low viscosity of collagen solutions, gels or dispersions commonly used for scaffold preparation. In the present study, we have developed a straightforward method which is based on 3D plotting of a highly viscous, high density collagen dispersion. The swollen state of the collagen fibrils at pH 4 enabled the homogenous extrusion of the material, the deposition of uniform strands and finally the construction of 3D scaffolds. Stabilization of the plotted structures was achieved by freeze-drying and chemical crosslinking with the carbodiimide EDC. The scaffolds exhibited high shape and dimensional fidelity and a hierarchical porosity consisting of macropores generated by strand deposition as well as an interconnected microporosity within the strands as result of the freeze-drying process. Cultivation of human mesenchymal stromal cells on the scaffolds, with and without adipogenic or osteogenic stimulation, revealed their cytocompatibility and potential applicability for adipose and bone tissue engineering. PMID:26924825

  9. Three dimensional patient-specific collagen architecture modulates cartilage responses in the knee joint during gait.

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    Räsänen, Lasse P; Mononen, Mika E; Lammentausta, Eveliina; Nieminen, Miika T; Jurvelin, Jukka S; Korhonen, Rami K

    2016-08-01

    Site-specific variation of collagen fibril orientations can affect cartilage stresses in knee joints. However, this has not been confirmed by 3-D analyses. Therefore, we present a novel method for evaluation of the effect of patient-specific collagen architecture on time-dependent mechanical responses of knee joint cartilage during gait. 3-D finite element (FE) models of a human knee joint were created with the collagen architectures obtained from T2 mapped MRI (patient-specific model) and from literature (literature model). The effect of accuracy of the implementation of collagen fibril architecture into the model was examined by using a submodel with denser FE mesh. Compared to the literature model, fibril strains and maximum principal stresses were reduced especially in the superficial/middle regions of medial tibial cartilage in the patient-specific model after the loading response of gait (up to -413 and -26%, respectively). Compared to the more coarsely meshed joint model, the patient-specific submodel demonstrated similar strain and stress distributions but increased values particularly in the superficial cartilage regions (especially stresses increased >60%). The results demonstrate that implementation of subject-specific collagen architecture of cartilage in 3-D modulates location- and time-dependent mechanical responses of human knee joint cartilage. Submodeling with more accurate implementation of collagen fibril architecture alters cartilage stresses particularly in the superficial/middle tissue. PMID:26714834

  10. Epithelial morphogenesis of MDCK cells in three-dimensional collagen culture is modulated by interleukin-8.

    Science.gov (United States)

    Wells, Erika K; Yarborough, OrLando; Lifton, Richard P; Cantley, Lloyd G; Caplan, Michael J

    2013-05-15

    Epithelial morphogenesis is dependent upon a variety of factors, many of which involve complex interactions between cells and their surrounding environments. We analyzed the patterns of differential gene expression associated with Madin-Darby canine kidney (MDCK) renal epithelial cells grown within a collagen gel in three-dimensional (3D) culture compared with those grown atop a collagen gel in two-dimensional (2D) culture. Under these conditions, MDCK cells spontaneously formed either hollow spherical cysts or flat monolayer sheets, respectively. Microarray analysis of gene expression revealed a twofold or greater expression difference in 732 gene sets from MDCK cysts compared with monolayers (false discovery rate or FDR-adjusted P values growth factor (HGF) induces MDCK cells in 3D culture to form linear tubule-like structures. We found that HGF stimulation caused MDCK cells in 3D culture to decrease the expression of IL-8 at both the mRNA and protein levels. Furthermore, the addition of recombinant IL-8 to HGF-stimulated 3D MDCK cultures was sufficient to partially reverse the tubulogenic effects of HGF, resulting in the formation of cystic structures. These data suggest that IL-8 participates in the formation of cystic structures by MDCK cells in 3D culture and that HGF may stimulate tubulogenesis through the suppression of IL-8. PMID:23485708

  11. Small-Angle X-ray Study of the Three-Dimensional Collagen/Mineral Superstructure in Intramuscular Fish Bone

    International Nuclear Information System (INIS)

    Synchrotron small-angle X-ray scattering (SAXS) was conducted on native intramuscular shad/herring bone samples. Two-dimensional SAXS patterns were quantitatively analyzed with special consideration for preferred orientation effects, leading to new insights into the three-dimensional superstructure of mineralized collagen fibrils in shad/herring bone

  12. Towards Tuning the Mechanical Properties of Three-Dimensional Collagen Scaffolds Using a Coupled Fiber-Matrix Model

    Directory of Open Access Journals (Sweden)

    Shengmao Lin

    2015-08-01

    Full Text Available Scaffold mechanical properties are essential in regulating the microenvironment of three-dimensional cell culture. A coupled fiber-matrix numerical model was developed in this work for predicting the mechanical response of collagen scaffolds subjected to various levels of non-enzymatic glycation and collagen concentrations. The scaffold was simulated by a Voronoi network embedded in a matrix. The computational model was validated using published experimental data. Results indicate that both non-enzymatic glycation-induced matrix stiffening and fiber network density, as regulated by collagen concentration, influence scaffold behavior. The heterogeneous stress patterns of the scaffold were induced by the interfacial mechanics between the collagen fiber network and the matrix. The knowledge obtained in this work could help to fine-tune the mechanical properties of collagen scaffolds for improved tissue regeneration applications.

  13. Morphological properties and proliferation analysis of olfactory ensheathing cells seeded onto three-dimensional collagen-heparan sulfate biological scaffolds

    Institute of Scientific and Technical Information of China (English)

    Na Liu; Zhouping Tang; Zhiyuan Yu; Minjie Xie; Yu Zhang; Erfang Yang; Shabei Xu

    2012-01-01

    This study aimed to examine the differences in the morphological properties and proliferation of ol-factory ensheathing cells in three-dimensional culture on collagen-heparan sulfate biological scaf-folds and in two-dimensional culture on common flat culture plates. The proliferation rate of olfactory ensheathing cells in three-dimensional culture was higher than that in two-dimensional culture, as detected by an MTT assay. In addition, more than half of the olfactory ensheathing cells subcultured using the trypsinization method in three-dimensional culture displayed a spindly Schwann cell-like morphology with extremely long processes, while they showed a flat astrocyte-like morphology in two-dimensional culture. Moreover, spindle-shaped olfactory ensheathing cells tended to adopt an elongated bipolar morphology under both culture conditions. Experimental findings indicate that the morphological properties and proliferation of olfactory ensheathing cells in three-dimensional culture on collagen-heparan sulfate biological scaffolds are better than those in two-dimensional culture.

  14. Three Dimensional Collagen Scaffold Promotes Intrinsic Vascularisation for Tissue Engineering Applications

    Science.gov (United States)

    Chan, Elsa C.; Kuo, Shyh-Ming; Kong, Anne M.; Morrison, Wayne A.; Dusting, Gregory J.; Mitchell, Geraldine M.

    2016-01-01

    Here, we describe a porous 3-dimensional collagen scaffold material that supports capillary formation in vitro, and promotes vascularization when implanted in vivo. Collagen scaffolds were synthesized from type I bovine collagen and have a uniform pore size of 80 μm. In vitro, scaffolds seeded with primary human microvascular endothelial cells suspended in human fibrin gel formed CD31 positive capillary-like structures with clear lumens. In vivo, after subcutaneous implantation in mice, cell-free collagen scaffolds were vascularized by host neovessels, whilst a gradual degradation of the scaffold material occurred over 8 weeks. Collagen scaffolds, impregnated with human fibrinogen gel, were implanted subcutaneously inside a chamber enclosing the femoral vessels in rats. Angiogenic sprouts from the femoral vessels invaded throughout the scaffolds and these degraded completely after 4 weeks. Vascular volume of the resulting constructs was greater than the vascular volume of constructs from chambers implanted with fibrinogen gel alone (42.7±5.0 μL in collagen scaffold vs 22.5±2.3 μL in fibrinogen gel alone; p<0.05, n = 7). In the same model, collagen scaffolds seeded with human adipose-derived stem cells (ASCs) produced greater increases in vascular volume than did cell-free collagen scaffolds (42.9±4.0 μL in collagen scaffold with human ASCs vs 25.7±1.9 μL in collagen scaffold alone; p<0.05, n = 4). In summary, these collagen scaffolds are biocompatible and could be used to grow more robust vascularized tissue engineering grafts with improved the survival of implanted cells. Such scaffolds could also be used as an assay model for studies on angiogenesis, 3-dimensional cell culture, and delivery of growth factors and cells in vivo. PMID:26900837

  15. Design and characterization of microcapsules-integrated collagen matrixes as multifunctional three-dimensional scaffolds for soft tissue engineering.

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    Del Mercato, Loretta L; Passione, Laura Gioia; Izzo, Daniela; Rinaldi, Rosaria; Sannino, Alessandro; Gervaso, Francesca

    2016-09-01

    Three-dimensional (3D) porous scaffolds based on collagen are promising candidates for soft tissue engineering applications. The addition of stimuli-responsive carriers (nano- and microparticles) in the current approaches to tissue reconstruction and repair brings about novel challenges in the design and conception of carrier-integrated polymer scaffolds. In this study, a facile method was developed to functionalize 3D collagen porous scaffolds with biodegradable multilayer microcapsules. The effects of the capsule charge as well as the influence of the functionalization methods on the binding efficiency to the scaffolds were studied. It was found that the binding of cationic microcapsules was higher than that of anionic ones, and application of vacuum during scaffolds functionalization significantly hindered the attachment of the microcapsules to the collagen matrix. The physical properties of microcapsules-integrated scaffolds were compared to pristine scaffolds. The modified scaffolds showed swelling ratios, weight losses and mechanical properties similar to those of unmodified scaffolds. Finally, in vitro diffusional tests proved that the collagen scaffolds could stably retain the microcapsules over long incubation time in Tris-HCl buffer at 37°C without undergoing morphological changes, thus confirming their suitability for tissue engineering applications. The obtained results indicate that by tuning the charge of the microcapsules and by varying the fabrication conditions, collagen scaffolds patterned with high or low number of microcapsules can be obtained, and that the microcapsules-integrated scaffolds fully retain their original physical properties. PMID:27219851

  16. Collagen type V enhances matrix contraction by human periodontal ligament fibroblasts seeded in three-dimensional collagen gels.

    NARCIS (Netherlands)

    Berendsen, A.D.; Bronckers, A.L.; Smit, T.H.; Walboomers, X.F.; Everts, V.

    2006-01-01

    Extracellular matrix components play an important role in modulating cellular activity. To study such capacities of the matrix, fibroblasts are frequently cultured in a three-dimensional gel and contraction is assessed as a measure of cellular activity. Since a connective tissue contains several typ

  17. Cancer Cell Invasion in Three-dimensional Collagen Is Regulated Differentially by Gα13 Protein and Discoidin Domain Receptor 1-Par3 Protein Signaling.

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    Chow, Christina R; Ebine, Kazumi; Knab, Lawrence M; Bentrem, David J; Kumar, Krishan; Munshi, Hidayatullah G

    2016-01-22

    Cancer cells can invade in three-dimensional collagen as single cells or as a cohesive group of cells that require coordination of cell-cell junctions and the actin cytoskeleton. To examine the role of Gα13, a G12 family heterotrimeric G protein, in regulating cellular invasion in three-dimensional collagen, we established a novel method to track cell invasion by membrane type 1 matrix metalloproteinase-expressing cancer cells. We show that knockdown of Gα13 decreased membrane type 1 matrix metalloproteinase-driven proteolytic invasion in three-dimensional collagen and enhanced E-cadherin-mediated cell-cell adhesion. E-cadherin knockdown reversed Gα13 siRNA-induced cell-cell adhesion but failed to reverse the effect of Gα13 siRNA on proteolytic invasion. Instead, concurrent knockdown of E-cadherin and Gα13 led to an increased number of single cells rather than groups of cells. Significantly, knockdown of discoidin domain receptor 1 (DDR1), a collagen-binding protein that also co-localizes to cell-cell junctions, reversed the effects of Gα13 knockdown on cell-cell adhesion and proteolytic invasion in three-dimensional collagen. Knockdown of the polarity protein Par3, which can function downstream of DDR1, also reversed the effects of Gα13 knockdown on cell-cell adhesion and proteolytic invasion in three-dimensional collagen. Overall, we show that Gα13 and DDR1-Par3 differentially regulate cell-cell junctions and the actin cytoskeleton to mediate invasion in three-dimensional collagen. PMID:26589794

  18. Effect of geometrical structure on drug release rate of a three-dimensionally perforated porous apatite/collagen composite cement.

    Science.gov (United States)

    Otsuka, Makoto; Nakagawa, Hidenori; Ito, Atsuo; Higuchi, William I

    2010-01-01

    To improve the biocompatibility, inter-connective pore structure, and drug delivery ability of self-setting apatite/collagen composite cement (ACC), a three-dimensionally perforated porous apatite/collagen composite cement (TPPACC) containing 3% indomethacin (IMC) was obtained in an arranged multi-cross with 20, 40, and 60 stainless steel needlelike male dies, and stored and hardened at 37 degrees C and 100% relative humidity for 24 h. The mean radius of micro-pores of the TPPACC was evaluated to be 0.125 microm by mercury porosimetry. X-ray powder diffraction and FT-IR spectroscopy suggested that TPPACC consisted of carbonated apatite and had a structure similar to that of natural rat bone. The IMC release rates from a TPPACC block containing the drug were measured in simulated body fluid. The rate of release increased with the number of macro-pores that from planar surface matrix systems followed the Higuchi equation. The relationship between the Higuchi constant and surface area of TPPACC showed a straight line with K = 0.2123 and R(2) = 0.9892. These results indicated that the rate of drug release from TPPACC could be controlled by the number of macro-pores for bone cells. PMID:19821491

  19. Fibronectin- and collagen-mimetic ligands regulate bone marrow stromal cell chondrogenesis in three-dimensional hydrogels

    Directory of Open Access Journals (Sweden)

    JT Connelly

    2011-09-01

    Full Text Available Modification of tissue engineering scaffolds with bioactive molecules is a potential strategy for modulating cell behavior and guiding tissue regeneration. While adhesion to RGD peptides has been shown to inhibit in vitro chondrogenesis, the effects of extracellular matrix (ECM-mimetic ligands with complex secondary and tertiary structures are unknown. This study aimed to determine whether collagen- and fibronectin-mimetic ligands would retain biologic functionality in three-dimensional (3D hydrogels, whether different ECM-mimetic ligands differentially influence in vitro chondrogenesis, and if effects of ligands on differentiation depend on soluble biochemical stimuli. A linear RGD peptide, a recombinant fibronectin fragment containing the seven to ten Type III repeats (FnIII7-10 and a triple helical, collagen mimetic peptide with the GFOGER motif were covalently coupled to agarose gels using the sulfo-SANPAH crosslinker, and bone marrow stromal cells (BMSCs were cultured within the 3D hydrogels. The ligands retained biologic functionality within the agarose gels and promoted density-dependent BMSC spreading. Interactions with all adhesive ligands inhibited stimulation by chondrogenic factors of collagen Type II and aggrecan mRNA levels and deposition of sulfated glycosaminoglycans. In medium containing fetal bovine serum, interactions with the GFOGER peptide enhanced mRNA expression of the osteogenic gene osteocalcin whereas FnIII7-10 inhibited osteocalcin expression. In conclusion, modification of agarose hydrogels with ECM-mimetic ligands can influence the differentiation of BMSCs in a manner that depends strongly on the presence and nature of soluble biochemical stimuli.

  20. Low-Temperature Additive Manufacturing of Biomimic Three-Dimensional Hydroxyapatite/Collagen Scaffolds for Bone Regeneration.

    Science.gov (United States)

    Lin, Kai-Feng; He, Shu; Song, Yue; Wang, Chun-Mei; Gao, Yi; Li, Jun-Qin; Tang, Peng; Wang, Zheng; Bi, Long; Pei, Guo-Xian

    2016-03-23

    Low-temperature additive manufacturing (AM) holds promise for fabrication of three-dimensional (3D) scaffolds containing bioactive molecules and/or drugs. Due to the strict technical limitations of current approaches, few materials are suitable for printing at low temperature. Here, a low-temperature robocasting method was employed to print biomimic 3D scaffolds for bone regeneration using a routine collagen-hydroxyapatite (CHA) composite material, which is too viscous to be printed via normal 3D printing methods at low temperature. The CHA scaffolds had excellent 3D structure and maintained most raw material properties after printing. Compared to nonprinted scaffolds, printed scaffolds promoted bone marrow stromal cell proliferation and improved osteogenic outcome in vitro. In a rabbit femoral condyle defect model, the interconnecting pores within the printed scaffolds facilitated cell penetration and mineralization before the scaffolds degraded and enhanced repair, compared to nonprinted CHA scaffolds. Additionally, the optimal printing parameters for 3D CHA scaffolds were investigated; 600-μm-diameter rods were optimal in terms of moderate mechanical strength and better repair outcome in vivo. This low-temperature robocasting method could enable a variety of bioactive molecules to be incorporated into printed CHA materials and provides a method of bioprinting biomaterials without compromising their natural properties. PMID:26930140

  1. Three-dimensional Biomimetic Technology: Novel Biorubber Creates Defined Micro- and Macro-scale Architectures in Collagen Hydrogels.

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    Rodriguez-Rivera, Veronica; Weidner, John W; Yost, Michael J

    2016-01-01

    Tissue scaffolds play a crucial role in the tissue regeneration process. The ideal scaffold must fulfill several requirements such as having proper composition, targeted modulus, and well-defined architectural features. Biomaterials that recapitulate the intrinsic architecture of in vivo tissue are vital for studying diseases as well as to facilitate the regeneration of lost and malformed soft tissue. A novel biofabrication technique was developed which combines state of the art imaging, three-dimensional (3D) printing, and selective enzymatic activity to create a new generation of biomaterials for research and clinical application. The developed material, Bovine Serum Albumin rubber, is reaction injected into a mold that upholds specific geometrical features. This sacrificial material allows the adequate transfer of architectural features to a natural scaffold material. The prototype consists of a 3D collagen scaffold with 4 and 3 mm channels that represent a branched architecture. This paper emphasizes the use of this biofabrication technique for the generation of natural constructs. This protocol utilizes a computer-aided software (CAD) to manufacture a solid mold which will be reaction injected with BSA rubber followed by the enzymatic digestion of the rubber, leaving its architectural features within the scaffold material. PMID:26967145

  2. Three-dimensional collagen I promotes gemcitabine resistance in vitro in pancreatic cancer cells through HMGA2-dependent histone acetyltransferase expression.

    Directory of Open Access Journals (Sweden)

    Surabhi Dangi-Garimella

    Full Text Available Pancreatic ductal adenocarcinoma (PDAC is associated with a pronounced collagen-rich stromal reaction that has been shown to contribute to chemo-resistance. We have previously shown that PDAC cells are resistant to gemcitabine chemotherapy in the collagen microenvironment because of increased expression of the chromatin remodeling protein high mobility group A2 (HMGA2. We have now found that human PDAC tumors display higher levels of histone H3K9 and H3K27 acetylation in fibrotic regions. We show that relative to cells grown on tissue culture plastic, PDAC cells grown in three-dimensional collagen gels demonstrate increased histone H3K9 and H3K27 acetylation, along with increased expression of p300, PCAF and GCN5 histone acetyltransferases (HATs. Knocking down HMGA2 attenuates the effect of collagen on histone H3K9 and H3K27 acetylation and on collagen-induced p300, PCAF and GCN5 expression. We also show that human PDAC tumors with HMGA2 demonstrate increased histone H3K9 and H3K27 acetylation. Additionally, we show that cells in three-dimensional collagen gels demonstrate increased protection against gemcitabine. Significantly, down-regulation of HMGA2 or p300, PCAF and GCN5 HATs sensitizes the cells to gemcitabine in three-dimensional collagen. Overall, our results increase our understanding of how the collagen microenvironment contributes to chemo-resistance in vitro and identify HATs as potential therapeutic targets against this deadly cancer.

  3. Effect of cold storage on collagen-based hydrogels for the three-dimensional culture of adipose-derived stem cells

    International Nuclear Information System (INIS)

    Collagen gels have been extensively used as three-dimensional (3D) cell culture systems. To enhance their mechanical properties, the manufacture of collagen-based gels with agarose has been proposed. However, little is known about the stability of these gels under cold storage conditions. The consequences of cold storage on biological tissues for clinical applications are known to be significant; yet, they have not been considered on hydrogels used for in vitro experiments. This work studies the effect of extended cold storage on the stability of collagen and collagen-agarose hydrogels using rheometry and scanning electron microscopy. In addition, cell-matrix interactions of adipose-derived stem cells (ADSC) have been studied using these gels. Results show that both the storage modulus (G′) and loss modulus (G″) of pure collagen gels gradually decrease with extended cold storage along the 30 days of the study, while G′ and G″ increase in collagen-agarose gels under the same conditions. Moreover, significant changes in both moduli of collagen-agarose gels were only found after 30 days of cold storage, while in the case of collagen gels significant changes were already detected after 7 days. Finally, a reduction in the ability of ADSC to remodel the gel after prolonged cold storage was observed. To the best of our knowledge, this is the first work proving that cold storage of hydrogels prior to cell culture might have a significant impact on their mechanical properties and cell–matrix interactions. (paper)

  4. Alignment of Astrocytes Increases Neuronal Growth in Three-Dimensional Collagen Gels and Is Maintained Following Plastic Compression to Form a Spinal Cord Repair Conduit

    OpenAIRE

    East, Emma; de Oliveira, Daniela Blum; Golding, Jon P.; Phillips, James B.

    2010-01-01

    After injury to the spinal cord, reactive astrocytes form a glial scar consisting of highly ramified cell processes that constitute a major impediment to repair, partly due to their lack of orientation and guidance for regenerating axons. In some nonmammalian vertebrates, successful central nervous system regeneration is attributed to the alignment of reactive glia, which guide axons across the lesion site. Here, a three-dimensional mammalian cell-seeded collagen gel culture system was used t...

  5. The effects of UVA irradiation on the metabolism of type I collagen and glycosaminoglycans by human dermal fibroblasts in three dimensional culture

    International Nuclear Information System (INIS)

    We studied the production of type I collagen and glycosaminoglycans by human dermal fibroblasts derived from young and old individuals after UVA irradiation. In these experiments, we introduced a new three-dimensional culture system supplemented with L-ascorbic acid 2-phosphate. In fibroblasts from old individuals (n=3), the amount of collagens in the cell layer was significantly decreased and matrix metallproteinase-1 (MMP-1) activity in the supernatant was significantly elevated after UVA irradiation, while the amounts of glycosaminoglycans in the cell layer and stromelysin-1 (MMP-3) activity showed no significant changes. In contrast, there were no significant changes after UVA irradiation of fibroblasts from young individuals (n=3). These results suggest that the donor age of dermal fibroblasts may be crucial to investigating the metabolism of type I collagen after UVA irradiation. (author)

  6. Three-dimensional optical disk data storage via the localized alteration of a format hologram.

    Science.gov (United States)

    McLeod, R R; Daiber, A J; Honda, T; McDonald, M E; Robertson, T L; Slagle, T; Sochava, S L; Hesselink, L

    2008-05-10

    Three-dimensional optical data storage is demonstrated in an initially homogenous volume by first recording a reflection grating in a holographic photopolymer. This causes the entire volume to be weakly reflecting to a confocal read/write head. Superposition of two or three such gratings with slightly different k-vectors creates a track and layer structure that specialized servo detection optics can use to lock the focus to these deeply-buried tracks. Writing is accomplished by locally modifying the reflectivity of the preexisting hologram. This modification can take the form of ablation, inelastic deformation via heating at the focus, or erasure via linear or two-photon continued polymerization in the previously unexposed fringes of the hologram. Storage by each method is demonstrated with up to eight data layers separated by as little as 12 microns. PMID:18470266

  7. The effect of glycosaminoglycan content on polyethylenimine-based gene delivery within three-dimensional collagen-GAG scaffolds

    OpenAIRE

    Hortensius, Rebecca A.; Becraft, Jacob R.; Pack, Daniel W.; Harley, Brendan A.C.

    2015-01-01

    The design of biomaterials for increasingly complex tissue engineering applications often requires exogenous presentation of biomolecular signals. Integration of gene delivery vectors with a biomaterial scaffold offers the potential to bypass the use of expensive and relatively inefficient growth factor supplementation strategies to augment cell behavior. However, integration of cationic polymer based gene delivery vectors within three-dimensional biomaterials, particularly matrices which can...

  8. Three-dimensional scaffold of type II collagen promote the differentiation of adipose-derived stem cells into a nucleus pulposus-like phenotype.

    Science.gov (United States)

    Zhou, Xiaopeng; Tao, Yiqing; Wang, Jingkai; Liu, Dongyu; Liang, Chengzhen; Li, Hao; Chen, Qixin

    2016-07-01

    Type II collagen is reported to have the capability of guiding adipose-derived stem cells (ADSCs) to differentiate towards a nucleus pulposus (NP)-like phenotype. So this study aimed to establish a three-dimensional (3D) collagen scaffold using N,N-(3-dimethylaminopropyl)-N'-ethyl carbodiimide and N-hydroxysuccinimide (EDAC/NHS) to increase the efficiency of ADSC differentiation into NP-like cells. Physical properties, such as porosity, biodegradation, and microstructure, and biological characteristics such as cytotoxicity, cell proliferation, and expression of relevant genes and proteins were measured to evaluate the efficacy of different scaffolds. Collagen scaffolds cross-linked with EDAC/NHS exhibited higher biological stability, better spatial structure, and higher gene and protein expression of functional markers such as aggrecan, SOX9 and COL2 than those of other groups. Based on the results, freeze-dried type II collagen cross-linked with EDAC/NHS formed the best 3D scaffold, for inducing ADSC proliferation and differentiation toward a NP-like phenotype. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 1687-1693, 2016. PMID:26940048

  9. Stiffness-controlled three-dimensional collagen scaffolds for differentiation of human Wharton's jelly mesenchymal stem cells into cardiac progenitor cells.

    Science.gov (United States)

    Lin, Yun-Li; Chen, Chie-Pein; Lo, Chun-Min; Wang, Hwai-Shi

    2016-09-01

    Stem cell-based regenerative therapy has emerged as a promising treatment for myocardial infarction. The aim of this study is to develop stiffness-controlled collagen scaffolds to allow proliferation and differentiation of mesenchymal stem cell (MSCs) into cardiac progenitor cells. In this study transforming growth factor β2 (TGF-β2), was used to induce stem cell differentiation into cardiac lineage cells. Collagen scaffolds were cross-linked with cross-linkers, 1-Ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC), and N-Hydroxysuccinimide (NHS). The results showed that collagen scaffolds cross-linked with 25/50 and 50/50 of EDC mM/NHS mM cross-linkers exhibited little difference in shape and size, the scaffold cross-linked with 50/50 of cross-linkers demonstrated better interconnectivity and higher Young's modulus (31.8 kPa) than the other (15.4 kPa). SEM observation showed that MSCs could grow inside the scaffolds and interact with collagen scaffolds. Furthermore, greater viability and cardiac lineage differentiation were achieved in MSCs cultured on stiffer scaffolds. The results suggest that three-dimensional type I collagen scaffolds with suitable cross-linking to adjust for stiffness can affect MSC fate and direct the differentiation of MSCs into cardiac progenitor cells with/without TGF-β2. These stiffness-controlled collagen scaffolds hold great potential as carriers for delivering MSCs differentiated cardiac progenitor cells into infracted hearts. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 2234-2242, 2016. PMID:27120780

  10. Three dimensional model evaluation of physical alterations of the Caloosahatchee River and Estuary: Impact on salt transport

    Science.gov (United States)

    Sun, Detong; Wan, Yongshan; Qiu, Chelsea

    2016-05-01

    Numerical hydrodynamic modeling provides quantitative understanding of how physical alterations of an estuary may alter the waterbody hydrodynamics and the rate of mixing with the ocean. In this study, a three dimensional hydrodynamic model (CH3D) was used to compare simulated salinities between the existing condition and five historical cases representing varying physical alterations of the Caloosahatchee Estuary involving (1) removal of the headwater structure (S-79); (2) removal of the downstream causeway to Sanibel Island; (3) backfilling an oyster bar near the estuary month; (4) refilling the navigation channel; and (5) the pre-development bathymetric condition. The results suggested that some alterations including the Sanibel Causeway, backfilling the oyster bar and the S-79 structure may have some local effects but did not change estuarine salinity structure significantly. Refilling the navigation channel had a more profound effect, resulting in a dry season salinity reduction of about 5 when compared with the existing condition. The reduced salt transport was more pronounced with the pre-development bathymetry because the estuary as a whole was much shallower than today. The significant system-wide increase in salt transport caused by the historic dredging of the navigation channel in the Caloosahatchee Estuary has significant implications in the development of attainable environmental flow targets for protecting the estuarine ecosystem.

  11. Three-dimensional analysis of abnormal ultrastructural alteration in mitochondria of hippocampus of APP/PSEN1 transgenic mouse

    Indian Academy of Sciences (India)

    Ki Ju Choi; Mi Jeong Kim; A Reum Je; Sangmi Jun; Chulhyun Lee; Eunji Lee; Mijung Jo; Yang Hoon Huh; Hee-Seok Kweon

    2014-03-01

    Alzheimer’s disease (AD) is a progressive neurodegenerative disorder. The deterioration of subcellular organelles, including the mitochondria, is another major ultrastructural characteristic of AD pathogenesis, in addition to amyloid plaque deposition. However, the three-dimensional (3-D) study of mitochondrial structural alteration in AD remains poorly understood. Therefore, ultrastructural analysis, 3-D electron tomography, and immunogold electron microscopy were performed in the present study to clarify the abnormal structural alterations in mitochondria caused by the progression of AD in APP/PSEN1 transgenic mice, expressing human amyloid precursor protein, as a model for AD. Amyloid (A) plaques accumulated and dystrophic neurites (DN) developed in the hippocampus of transgenic AD mouse brains. We also identified the loss of peroxiredoxin 3, an endogenous cytoprotective antioxidant enzyme and the accumulation of A in the hippocampal mitochondria of transgenic mice, which differs from those in age-matched wild-type mice. The mitochondria in A plaque-detected regions were severely disrupted, and the patterns of ultrastructural abnormalities were classified into three groups: disappearance of cristae, swelling of cristae, and bulging of the outer membrane. These results demonstrated that morpho-functional alterations of mitochondria and AD progression are closely associated and may be beneficial in investigating the function of mitochondria in AD pathogenesis.

  12. Infection by Toxoplasma gondii Induces Amoeboid-Like Migration of Dendritic Cells in a Three-Dimensional Collagen Matrix.

    Directory of Open Access Journals (Sweden)

    Sachie Kanatani

    Full Text Available Toxoplasma gondii, an obligate intracellular parasite of humans and other warm-blooded vertebrates, invades a variety of cell types in the organism, including immune cells. Notably, dendritic cells (DCs infected by T. gondii acquire a hypermigratory phenotype that potentiates parasite dissemination by a 'Trojan horse' type of mechanism in mice. Previous studies have demonstrated that, shortly after parasite invasion, infected DCs exhibit hypermotility in 2-dimensional confinements in vitro and enhanced transmigration in transwell systems. However, interstitial migration in vivo involves interactions with the extracellular matrix in a 3-dimensional (3D space. We have developed a collagen matrix-based assay in a 96-well plate format that allows quantitative locomotion analyses of infected DCs in a 3D confinement over time. We report that active invasion of DCs by T. gondii tachyzoites induces enhanced migration of infected DCs in the collagen matrix. Parasites of genotype II induced superior DC migratory distances than type I parasites. Moreover, Toxoplasma-induced hypermigration of DCs was further potentiated in the presence of the CCR7 chemotactic cue CCL19. Blocking antibodies to integrins (CD11a, CD11b, CD18, CD29, CD49b insignificantly affected migration of infected DCs in the 3D matrix, contrasting with their inhibitory effects on adhesion in 2D assays. Morphological analyses of infected DCs in the matrix were consistent with the acquisition of an amoeboid-like migratory phenotype. Altogether, the present data show that the Toxoplasma-induced hypermigratory phenotype in a 3D matrix is consistent with integrin-independent amoeboid DC migration with maintained responsiveness to chemotactic and chemokinetic cues. The data support the hypothesis that induction of amoeboid hypermigration and chemotaxis/chemokinesis in infected DCs potentiates the dissemination of T. gondii.

  13. Differentiation of Wharton's Jelly-Derived Mesenchymal Stem Cells into Motor Neuron-Like Cells on Three-Dimensional Collagen-Grafted Nanofibers.

    Science.gov (United States)

    Bagher, Zohreh; Azami, Mahmoud; Ebrahimi-Barough, Somayeh; Mirzadeh, Hamid; Solouk, Atefeh; Soleimani, Mansooreh; Ai, Jafar; Nourani, Mohammad Reza; Joghataei, Mohammad Taghi

    2016-05-01

    Cell transplantation strategies have provided potential therapeutic approaches for treatment of neurodegenerative diseases. Mesenchymal stem cells from Wharton's jelly (WJMSCs) are abundant and available adult stem cells with low immunological incompatibility, which could be considered for cell replacement therapy in the future. However, MSC transplantation without any induction or support material causes poor control of cell viability and differentiation. In this study, we investigated the effect of the nanoscaffolds on WJMSCs differentiation into motor neuronal lineages in the presence of retinoic acid (RA) and sonic hedgehog (Shh). Surface properties of scaffolds have been shown to significantly influence cell behaviors such as adhesion, proliferation, and differentiation. Therefore, polycaprolactone (PCL) nanofibers were constructed via electrospinning, surface modified by plasma treatment, and grafted by collagen. Characterization of the scaffolds by means of ATR-FTIR, contact angel, and Bradford proved grafting of the collagen on the surface of the scaffolds. WJMSCs were seeded on nanofibrous and tissue culture plate (TCP) and viability of WJMSCs were measured by MTT assay and then induced to differentiate into motor neuron-like cells for 15 days. Differentiated cells were evaluated morphologically, and real-time PCR and immunocytochemistry methods were done to evaluate expression of motor neuron-like cell markers in mRNA and protein levels. Our results showed that obtained cells could express motor neuron biomarkers at both RNA and protein levels, but the survival and differentiation of WJMSCs into motor neuron-like cells on the PCL/collagen scaffold were higher than cultured cells in the TCP and PCL groups. Taken together, WJMSCs are an attractive stem cell source for inducing into motor neurons in vitro especially when grown on nanostructural scaffolds and PCL/collagen scaffolds can provide a suitable, three-dimensional situation for neuronal survival and

  14. Three-dimensional disorganization of the cancer genome occurs coincident with long-range genetic and epigenetic alterations.

    Science.gov (United States)

    Taberlay, Phillippa C; Achinger-Kawecka, Joanna; Lun, Aaron T L; Buske, Fabian A; Sabir, Kenneth; Gould, Cathryn M; Zotenko, Elena; Bert, Saul A; Giles, Katherine A; Bauer, Denis C; Smyth, Gordon K; Stirzaker, Clare; O'Donoghue, Sean I; Clark, Susan J

    2016-06-01

    A three-dimensional chromatin state underpins the structural and functional basis of the genome by bringing regulatory elements and genes into close spatial proximity to ensure proper, cell-type-specific gene expression profiles. Here, we performed Hi-C chromosome conformation capture sequencing to investigate how three-dimensional chromatin organization is disrupted in the context of copy-number variation, long-range epigenetic remodeling, and atypical gene expression programs in prostate cancer. We find that cancer cells retain the ability to segment their genomes into megabase-sized topologically associated domains (TADs); however, these domains are generally smaller due to establishment of additional domain boundaries. Interestingly, a large proportion of the new cancer-specific domain boundaries occur at regions that display copy-number variation. Notably, a common deletion on 17p13.1 in prostate cancer spanning the TP53 tumor suppressor locus results in bifurcation of a single TAD into two distinct smaller TADs. Change in domain structure is also accompanied by novel cancer-specific chromatin interactions within the TADs that are enriched at regulatory elements such as enhancers, promoters, and insulators, and associated with alterations in gene expression. We also show that differential chromatin interactions across regulatory regions occur within long-range epigenetically activated or silenced regions of concordant gene activation or repression in prostate cancer. Finally, we present a novel visualization tool that enables integrated exploration of Hi-C interaction data, the transcriptome, and epigenome. This study provides new insights into the relationship between long-range epigenetic and genomic dysregulation and changes in higher-order chromatin interactions in cancer. PMID:27053337

  15. A tailored three-dimensionally printable agarose-collagen blend allows encapsulation, spreading, and attachment of human umbilical artery smooth muscle cells.

    Science.gov (United States)

    Köpf, Marius; Campos, Daniela F Duarte; Blaeser, Andreas; Sen, Kshama S; Fischer, Horst

    2016-01-01

    In recent years, novel biofabrication technologies have enabled the rapid manufacture of hydrogel-cell suspensions into tissue-imitating constructs. The development of novel materials for biofabrication still remains a challenge due to a gap between contradicting requirements such as three-dimensional printability and optimal cytocompatibility. We hypothesise that blending of different hydrogels could lead to a novel material with favourable biological and printing properties. In our work, we combined agarose and type I collagen in order to develop a hydrogel blend capable of long-term cell encapsulation of human umbilical artery smooth muscle cells (HUASMCs) and 3D drop-on-demand printing. Different blends were prepared with 0.25%, 0.5%, 0.75%, and 1.5% agarose and 0.2% type I collagen. The cell morphology of HUASMCs and the printing accuracy were assessed for each agarose-collagen combination, keeping the content of collagen constant. The hydrogel blend which displayed sufficient cell spreading and printing accuracy (0.5% agarose, 0.2% type I collagen, AGR0.5COLL0.2) was then characterised based on swelling and degradation over 21 days and mechanical stiffness. The cellular response regarding cell attachment of HUASMCs embedded in the hydrogel blend was further studied using SEM, TEM, and TPLSM. Printing trials were fabricated in a drop-on-demand printing process. The swelling and degradation evaluation showed an average of 20% mass loss and less than 10% swelling. AGR0.5COLL0.2 exhibited significant increase in stiffness compared to pure agarose and type I collagen. In addition, columns of AGR0.5COLL0.2 three centimeters in height were successfully printed submerged in cooled perfluorocarbon, proving the intrinsic printability of the hydrogel blend. Ultimately, a promising novel hydrogel blend showing cell spreading and attachment as well as suitability for bioprinting was identified and could, for example, serve in the manufacture of in vitro 3D models to

  16. Three-dimensional poly (ε-caprolactone)/hydroxyapatite/collagen scaffolds incorporating bone marrow mesenchymal stem cells for the repair of bone defects.

    Science.gov (United States)

    Qi, Xin; Huang, Yinjun; Han, Dan; Zhang, Jieyuan; Cao, Jiaqing; Jin, Xiangyun; Huang, Jinghuan; Li, Xiaolin; Wang, Ting

    2016-04-01

    We previously demonstrated that three-dimensional (3D) hydroxyapatite (HAP)-collagen (COL)-coated poly(ε-caprolactone) (PCL) scaffolds (HAP-COL-PCL) possess appropriate nano-structures, surface roughness, and nutrients, providing a favorable environment for osteogenesis. However, the effect of using 3D HAP-COL-PCL scaffolds incorporating BMSCs for the repair of bone defects in rats has been not evaluated. 3D PCL scaffolds coated with HAP, collagen or HAP/COL and incorporating BMSCs were implanted into calvarial defects. At 12 weeks after surgery, the rats were sacrificed and crania were harvested to assess the bone defect repair using microcomputed tomography (micro-CT), histology, immunohistochemistry and sequential fluorescent labeling analysis. 3D micro-CT reconstructed images and quantitative analysis showed that HAP-COL-PCL groups possessed better bone-forming capacity than HAP-PCL groups or COL-PCL groups. Fluorescent labeling analysis revealed the percentage of tetracycline labeling, alizarin red labeling, and calcein labeling in HAP-COL-PCL groups were all greater than in the other two groups (P rats. PMID:26964015

  17. Polarized Microscopy in Lesions With Altered Dermal Collagen.

    Science.gov (United States)

    Elbendary, Amira; Valdebran, Manuel; Parikh, Kruti; Elston, Dirk M

    2016-08-01

    Alterations in dermal collagen are noted in dermatofibroma, dermatofibrosarcoma protuberans, morphea, lichen sclerosus et atrophicus, hypertrophic scars, and keloids. The authors sought to determine whether variations in birefringence of collagen by polarized microscopy could be of help in diagnosing such conditions. Representative hematoxylin and eosin sections of 400 cases, including dermatofibroma, dermatofibrosarcoma protuberans, hypertrophic scars, keloid, morphea, and lichen sclerosus, were examined under polarized microscopy. Distinct patterns of birefringence of collagen for each disease were noted under polarized microscopy. This study highlights the use of polarized microscopy as adjunctive tool in differentiating different diseases with collagen alteration. PMID:26959692

  18. Optimal Seeding Densities for In Vitro Chondrogenesis of Two- and Three-Dimensional-Isolated and -Expanded Bone Marrow-Derived Mesenchymal Stromal Stem Cells Within a Porous Collagen Scaffold

    OpenAIRE

    Bornes, Troy D.; Jomha, Nadr M; Mulet-Sierra, Aillette; Adesida, Adetola B.

    2016-01-01

    Bone marrow-derived mesenchymal stromal stem cells (BMSCs) are a promising cell source for treating articular cartilage defects. The objective of this study was to assess the impact of cell seeding density within a collagen I scaffold on in vitro BMSC chondrogenesis following isolation and expansion in two-dimensional (2D) and three-dimensional (3D) environments. It was hypothesized that both expansion protocols would produce BMSCs capable of hyaline-like chondrogenesis with an optimal seedin...

  19. Osteoinduction and proliferation of bone-marrow stromal cells in three-dimensional poly (ε-caprolactone)/ hydroxyapatite/collagen scaffolds

    OpenAIRE

    Wang, Ting; Yang, Xiaoyan; Qi, Xin; Jiang, Chaoyin

    2015-01-01

    Background Osteoinduction and proliferation of bone-marrow stromal cells (BMSCs) in three-dimensional (3D) poly(ε-caprolactone) (PCL) scaffolds have not been studied throughly and are technically challenging. This study aimed to optimize nanocomposites of 3D PCL scaffolds to provide superior adhesion, proliferation and differentiation environment for BMSCs in this scenario. Methods BMSCs were isolated and cultured in a novel 3D tissue culture poly(ε-caprolactone) (PCL) scaffold coated with po...

  20. Development of a micromanipulator-based loading device for mechanoregulation study of human mesenchymal stem cells in three-dimensional collagen constructs

    OpenAIRE

    AuYeung, KL; Sze, KY; Sham, MH; Chan, BP

    2010-01-01

    Mechanical signal is important for regulating cellular activities, including proliferation, metabolism, matrix production, and orientation. Bioreactors with loading functions can be used to precondition cells in three-dimensional (3D) constructs so as to study the cellular responses to mechanical stimulation. However, full-scale bioreactor is not always an affordable option considering the high cost of equipments and the liter-sized medium with serum and growth factor supplements. In this stu...

  1. Real-time two- and three-dimensional imaging of monocyte motility and navigation on planar surfaces and in collagen matrices: roles of Rho

    Science.gov (United States)

    Bzymek, Robert; Horsthemke, Markus; Isfort, Katrin; Mohr, Simon; Tjaden, Kerstin; Müller-Tidow, Carsten; Thomann, Marlies; Schwerdtle, Tanja; Bähler, Martin; Schwab, Albrecht; Hanley, Peter J.

    2016-01-01

    We recently found that macrophages from RhoA/RhoB double knockout mice had increased motility of the cell body, but severely impaired retraction of the tail and membrane extensions, whereas RhoA- or RhoB-deficient cells exhibited mild phenotypes. Here we extended this work and investigated the roles of Rho signaling in primary human blood monocytes migrating in chemotactic gradients and in various settings. Monocyte velocity, but not chemotactic navigation, was modestly dependent on Rho-ROCK-myosin II signaling on a 2D substrate or in a loose collagen type I matrix. Viewed by time-lapse epi-fluorescence microscopy, monocytes appeared to flutter rather than crawl, such that the 3D surface topology of individual cells was difficult to predict. Spinning disk confocal microscopy and 3D reconstruction revealed that cells move on planar surfaces and in a loose collagen matrix using prominent, curved planar protrusions, which are rapidly remodeled and reoriented, as well as resorbed. In a dense collagen type I matrix, there is insufficient space for this mode and cells adopt a highly Rho-dependent, lobular mode of motility. Thus, in addition to its role in tail retraction on 2D surfaces, Rho is critical for movement in confined spaces, but is largely redundant for motility and chemotaxis in loose matrices. PMID:27122054

  2. MT1-MMP promotes cell growth and ERK activation through c-Src and paxillin in three-dimensional collagen matrix

    Energy Technology Data Exchange (ETDEWEB)

    Takino, Takahisa; Tsuge, Hisashi; Ozawa, Terumasa [Department of Molecular Virology and Oncology, Cancer Research Institute, Kanazawa University, Kakuma-machi, Kanazawa 920-1192 (Japan); Sato, Hiroshi, E-mail: vhsato@kenroku.kanazawa-u.ac.jp [Department of Molecular Virology and Oncology, Cancer Research Institute, Kanazawa University, Kakuma-machi, Kanazawa 920-1192 (Japan)

    2010-06-11

    Membrane-type 1 matrix metalloproteinase (MT1-MMP) is essential for tumor invasion and growth. We show here that MT1-MMP induces extracellular signal-regulated kinase (ERK) activation in cancer cells cultured in collagen gel, which is indispensable for their proliferation. Inhibition of MT1-MMP by MMP inhibitor or small interfering RNA suppressed activation of focal adhesion kinase (FAK) and ERK in MT1-MMP-expressing cancer cells, which resulted in up-regulation of p21{sup WAF1} and suppression of cell growth in collagen gel. Cell proliferation was also abrogated by the inhibitor against ERK pathway without affecting FAK phosphorylation. MT1-MMP and integrin {alpha}{sub v}{beta}{sub 3} were shown to be involved in c-Src activation, which induced FAK and ERK activation in collagen gel. These MT1-MMP-mediated signal transductions were paxillin dependent, as knockdown of paxillin reduced cell growth and ERK activation, and co-expression of MT1-MMP with paxillin induced ERK activation. The results suggest that MT1-MMP contributes to proliferation of cancer cells in the extracellular matrix by activating ERK through c-Src and paxillin.

  3. Disruption of TgPHIL1 alters specific parameters of Toxoplasma gondii motility measured in a quantitative, three-dimensional live motility assay.

    Directory of Open Access Journals (Sweden)

    Jacqueline M Leung

    Full Text Available T. gondii uses substrate-dependent gliding motility to invade cells of its hosts, egress from these cells at the end of its lytic cycle and disseminate through the host organism during infection. The ability of the parasite to move is therefore critical for its virulence. T. gondii engages in three distinct types of gliding motility on coated two-dimensional surfaces: twirling, circular gliding and helical gliding. We show here that motility in a three-dimensional Matrigel-based environment is strikingly different, in that all parasites move in irregular corkscrew-like trajectories. Methods developed for quantitative analysis of motility parameters along the smoothed trajectories demonstrate a complex but periodic pattern of motility with mean and maximum velocities of 0.58 ± 0.07 µm/s and 2.01 ± 0.17 µm/s, respectively. To test how a change in the parasite's crescent shape might affect trajectory parameters, we compared the motility of Δphil1 parasites, which are shorter and wider than wild type, to the corresponding parental and complemented lines. Although comparable percentages of parasites were moving for all three lines, the Δphil1 mutant exhibited significantly decreased trajectory lengths and mean and maximum velocities compared to the parental parasite line. These effects were either partially or fully restored upon complementation of the Δphil1 mutant. These results show that alterations in morphology may have a significant impact on T. gondii motility in an extracellular matrix-like environment, provide a possible explanation for the decreased fitness of Δphil1 parasites in vivo, and demonstrate the utility of the quantitative three-dimensional assay for studying parasite motility.

  4. Disruption of TgPHIL1 alters specific parameters of Toxoplasma gondii motility measured in a quantitative, three-dimensional live motility assay.

    Science.gov (United States)

    Leung, Jacqueline M; Rould, Mark A; Konradt, Christoph; Hunter, Christopher A; Ward, Gary E

    2014-01-01

    T. gondii uses substrate-dependent gliding motility to invade cells of its hosts, egress from these cells at the end of its lytic cycle and disseminate through the host organism during infection. The ability of the parasite to move is therefore critical for its virulence. T. gondii engages in three distinct types of gliding motility on coated two-dimensional surfaces: twirling, circular gliding and helical gliding. We show here that motility in a three-dimensional Matrigel-based environment is strikingly different, in that all parasites move in irregular corkscrew-like trajectories. Methods developed for quantitative analysis of motility parameters along the smoothed trajectories demonstrate a complex but periodic pattern of motility with mean and maximum velocities of 0.58 ± 0.07 µm/s and 2.01 ± 0.17 µm/s, respectively. To test how a change in the parasite's crescent shape might affect trajectory parameters, we compared the motility of Δphil1 parasites, which are shorter and wider than wild type, to the corresponding parental and complemented lines. Although comparable percentages of parasites were moving for all three lines, the Δphil1 mutant exhibited significantly decreased trajectory lengths and mean and maximum velocities compared to the parental parasite line. These effects were either partially or fully restored upon complementation of the Δphil1 mutant. These results show that alterations in morphology may have a significant impact on T. gondii motility in an extracellular matrix-like environment, provide a possible explanation for the decreased fitness of Δphil1 parasites in vivo, and demonstrate the utility of the quantitative three-dimensional assay for studying parasite motility. PMID:24489670

  5. The influence of particle size and static magnetic fields on the uptake of magnetic nanoparticles into three dimensional cell-seeded collagen gel cultures.

    Science.gov (United States)

    Lewis, Emily E L; Child, Hannah W; Hursthouse, Andrew; Stirling, David; McCully, Mark; Paterson, David; Mullin, Margaret; Berry, Catherine C

    2015-08-01

    Over recent decades there has been and continues to be major advances in the imaging, diagnosis and potential treatment of medical conditions, by the use of magnetic nanoparticles. However, to date the majority of cell delivery studies employ a traditional 2D monolayer culture. This article aims to determine the ability of various sized magnetic nanoparticles to penetrate and travel through a cell seeded collagen gel model, in the presence or absence of a magnetic field. Three different sized (100, 200, and 500 nm) nanoparticles were employed in the study. The results showed cell viability was unaffected by the presence of nanoparticles over a 24-h test period. The initial uptake of the 100 nm nanoparticle into the collagen gel structure was superior compared to the larger sized nanoparticles under the influence of a magnetic field and incubated for 24 h. Interestingly, it was the 200 nm nanoparticles, which proved to penetrate the gel furthest, under the influence of a magnetic field, during the initial culture stage after 1-h incubation. PMID:25358626

  6. Optimal Seeding Densities for In Vitro Chondrogenesis of Two- and Three-Dimensional-Isolated and -Expanded Bone Marrow-Derived Mesenchymal Stromal Stem Cells Within a Porous Collagen Scaffold.

    Science.gov (United States)

    Bornes, Troy D; Jomha, Nadr M; Mulet-Sierra, Aillette; Adesida, Adetola B

    2016-03-01

    Bone marrow-derived mesenchymal stromal stem cells (BMSCs) are a promising cell source for treating articular cartilage defects. The objective of this study was to assess the impact of cell seeding density within a collagen I scaffold on in vitro BMSC chondrogenesis following isolation and expansion in two-dimensional (2D) and three-dimensional (3D) environments. It was hypothesized that both expansion protocols would produce BMSCs capable of hyaline-like chondrogenesis with an optimal seeding density of 10 × 10(6) cells/cm(3). Ovine BMSCs were isolated in a 2D environment by plastic adherence, expanded to passage two in flasks containing an expansion medium, and seeded within collagen I scaffolds at densities of 50, 10, 5, 1, and 0.5 × 10(6) BMSCs/cm(3). For 3D isolation and expansion, aspirates containing known quantities of mononucleated cells (bone marrow-derived mononucleated cells [BMNCs]) were seeded on scaffolds at 50, 10, 5, 1, and 0.5 × 10(6) BMNCs/cm(3) and cultured in the expansion medium for an equivalent duration to 2D expansion. Constructs were differentiated in vitro in the chondrogenic medium for 21 days and assessed with reverse-transcription quantitative polymerase chain reaction, safranin O staining, histological scoring using the Bern Score, collagen immunofluorescence, and glycosaminoglycan (GAG) quantification. Two-dimensional-expanded BMSCs seeded at all densities were capable of proteoglycan production and displayed increased expressions of aggrecan and collagen II messenger RNA (mRNA) relative to predifferentiation controls. Collagen II deposition was apparent in scaffolds seeded at 0.5-10 × 10(6) BMSCs/cm(3). Chondrogenesis of 2D-expanded BMSCs was most pronounced in scaffolds seeded at 5-10 × 10(6) BMSCs/cm(3) based on aggrecan and collagen II mRNA, safranin O staining, Bern Score, total GAG, and GAG/deoxyribonucleic acid (DNA). For 3D-expanded BMSC-seeded scaffolds, increased aggrecan and collagen II m

  7. The Evaluation for Alterations of DOM Components from Upstream to Downstream Flow of Rivers in Toyama (Japan Using Three-Dimensional Excitation-Emission Matrix Fluorescence Spectroscopy

    Directory of Open Access Journals (Sweden)

    Hideki Kuramitz

    2011-05-01

    Full Text Available The dissolved organic matter (DOM is one of the important factors for controlling water quality. The behavior and constitutions of DOM is related to the risk of human health because it is able to directly or indirectly affect the behavior, speciation and toxicity of various environmental pollutants. However, it is not easy to know the contents of DOM components without using various complicated and time consuming analytical methods because DOM is a complex mixture and usually exists at low concentration. Here, we describe the fluorescence properties of DOM components in water samples collected from four rivers in Toyama, Japan by means of the three-dimensional excitation-emission matrix (3DEEM fluorescence spectroscopy. In order to evaluate the alterations of DOM components in each of the river during the flow from upstream to downstream, the patterns of relative fluorescence intensity (RFI at six peaks which are originated from fluorophores including humic-like and protein-like components were investigated. The changes in the patterns of RFI values at each of the peak and the concentration of dissolved organic carbon (DOC for each river water sample were discussed in connection with the differences of land use managements and basic water quality parameters, such as pH, EC, turbidity, Fe3+, T-N, NO3-N, T-P, PO4-P, chlorophyll a, DOC and N/P ratio. The DOC concentrations in the water samples collected from these rivers were relatively low (0.63–1.16 mg/L. Two main peaks which have a strong RFI value expressed a positive correlation with the DOC concentration (r = 0.557, 0.535. However, the correlations between the RFI values for other four peaks and the DOC concentration were below 0.287. The alterations of DOM components during the flow of a river from upstream to downstream were investigated from the changes in the patterns of RFI values for six fluorescent peaks. It was clarified that the great increase of RFI values in peak A and peak T

  8. Three-dimensional metamaterials

    Science.gov (United States)

    Burckel, David Bruce

    2012-06-12

    A fabrication method is capable of creating canonical metamaterial structures arrayed in a three-dimensional geometry. The method uses a membrane suspended over a cavity with predefined pattern as a directional evaporation mask. Metallic and/or dielectric material can be evaporated at high vacuum through the patterned membrane to deposit resonator structures on the interior walls of the cavity, thereby providing a unit cell of micron-scale dimension. The method can produce volumetric metamaterial structures comprising layers of such unit cells of resonator structures.

  9. Three dimensional system integration

    CERN Document Server

    Papanikolaou, Antonis; Radojcic, Riko

    2010-01-01

    Three-dimensional (3D) integrated circuit (IC) stacking is the next big step in electronic system integration. It enables packing more functionality, as well as integration of heterogeneous materials, devices, and signals, in the same space (volume). This results in consumer electronics (e.g., mobile, handheld devices) which can run more powerful applications, such as full-length movies and 3D games, with longer battery life. This technology is so promising that it is expected to be a mainstream technology a few years from now, less than 10-15 years from its original conception. To achieve thi

  10. Three-Dimensional Flows

    CERN Document Server

    Araujo, Vitor; Viana, Marcelo

    2010-01-01

    In this book, the authors present the elements of a general theory for flows on three-dimensional compact boundaryless manifolds, encompassing flows with equilibria accumulated by regular orbits. The book aims to provide a global perspective of this theory and make it easier for the reader to digest the growing literature on this subject. This is not the first book on the subject of dynamical systems, but there are distinct aspects which together make this book unique. Firstly, this book treats mostly continuous time dynamical systems, instead of its discrete counterpart, exhaustively treated

  11. Observations on morphologic changes in the aging and degenerating human disc: Secondary collagen alterations

    Directory of Open Access Journals (Sweden)

    Hanley Edward N

    2002-03-01

    Full Text Available Abstract Background In the annulus, collagen fibers that make up the lamellae have a wavy, planar crimped pattern. This crimping plays a role in disc biomechanical function by allowing collagen fibers to stretch during compression. The relationship between morphologic changes in the aging/degenerating disc and collagen crimping have not been explored. Methods Ultrastructural studies were performed on annulus tissue from 29 control (normal donors (aged newborn to 79 years and surgical specimens from 49 patients (aged 16 to 77 years. Light microscopy and specialized image analysis to visualize crimping was performed on additional control and surgical specimens. Human intervertebral disc tissue from the annulus was obtained in a prospective morphologic study of the annulus. Studies were approved by the authors' Human Subjects Institutional Review Board. Results Three types of morphologic changes were found to alter the crimping morphology of collagen: 1 encircling layers of unusual matrix disrupted the lamellar collagen architecture; 2 collagen fibers were reduced in amount, and 3 collagen was absent in regions with focal matrix loss. Conclusions Although proteoglycan loss is well recognized as playing a role in the decreased shock absorber function of the aging/degenerating disc, collagen changes have received little attention. This study suggests that important stretch responses of collagen made possible by collagen crimping may be markedly altered by morphologic changes during aging/degeneration and may contribute to the early tissue changes involved in annular tears.

  12. Reestablishment of three-dimensional cardiac tissue architecture in porous collagen scaffolds%在多孔胶原支架上构建三维工程的心肌组织

    Institute of Scientific and Technical Information of China (English)

    刘兴茂; 陈昭烈; 刘红; 吴本传; 熊福银; 胥照平

    2004-01-01

    equivalent for scientific studies and tissue repair. Biosynthetic constructs have been described that would replace or augment bone, cartilage, kidney, liver, neuronal tissue and skin.OBJECTIVE: To explore feasibility of porous collagen as three-dimensional cardiac scaffolds for tissue architecture.DESIGN: A non-randomized controlled experimental study.SETTING and PARTICIPANTS: The study was completed in the Institute of Biotechnology, Academy of Military Medical Sciences. Subjects were neonatal Wistar rats(1 day old, 8 - 10 g, clean grade) and adult Wistar (250 g) from the Laboratory Animal Center, Academy of Military Medical Sciences. Temperature and humidity of breeding were 22 - 26 ℃ and 40%- 60% respectively.INTERVENTIONS: Cardiac cells enzymatically digested from neonatal rats were seeded to three-dimensional porous collagen scaffolds and plastic plates. Metabolic characteristics of cardiac cells cultured between two culture modes were compared.MAIN OUTCOME MEASURES: The specific consumption rate of glucose(qg1c), specific production rate of lactate(q1ac), lactate transform rate(Y1aac/g1c), creatine kinase(CK) and lactate dehydrogenase(LDH) activities of cardiac cells.RESULTS: The metabolic characteristic of cardiac cells cultured in collagen scaffolds was similar to that cultured in polystyrene plates in two-dimensional mode.CONCLUSION: Synchronous and rhythmical contractile tissue constructs in vitro can be formed by cultivation of cardiac cells on porous collagen scaffolds. Porous collagen can be used as scaffolds in cardiac tissue engineering.

  13. Heat Shock Protein 47: A Novel Biomarker of Phenotypically Altered Collagen-Producing Cells

    International Nuclear Information System (INIS)

    Heat shock protein 47 (HSP47) is a collagen-specific molecular chaperone that helps the molecular maturation of various types of collagens. A close association between increased expression of HSP47 and the excessive accumulation of collagens is found in various human and experimental fibrotic diseases. Increased levels of HSP47 in fibrotic diseases are thought to assist in the increased assembly of procollagen, and thereby contribute to the excessive deposition of collagens in fibrotic areas. Currently, there is not a good universal histological marker to identify collagen-producing cells. Identifying phenotypically altered collagen-producing cells is essential for the development of cell-based therapies to reduce the progression of fibrotic diseases. Since HSP47 has a single substrate, which is collagen, the HSP47 cellular expression provides a novel universal biomarker to identify phenotypically altered collagen-producing cells during wound healing and fibrosis. In this brief article, we explained why HSP47 could be used as a universal marker for identifying phenotypically altered collagen-producing cells

  14. A cell adhesion molecule mimetic, FGL peptide, induces alterations in synapse and dendritic spine structure in the dentate gyrus of aged rats: a three-dimensional ultrastructural study

    DEFF Research Database (Denmark)

    Popov, Victor I; Medvedev, Nikolay I; Kraev, Igor V;

    2008-01-01

    100 serial ultrathin sections. FGL affected neither hippocampal volume nor spine or synaptic density in the middle molecular layer of the dentate gyrus. However, it increased the ratio of mushroom to thin spines, number of multivesicular bodies and also increased the frequency of appearance of coated...... pits. Three-dimensional analysis showed a significant decrease in both post-synaptic density and apposition zone curvature of mushroom spines following FGL treatment, whereas for thin spines the convexity of the apposition zone increased. These data indicate that FGL induces large changes in the fine...

  15. The collagen turnover profile is altered in patients with inguinal and incisional hernia

    DEFF Research Database (Denmark)

    Henriksen, Nadia A; Mortensen, Joachim H; Sorensen, Lars T;

    2015-01-01

    the interstitial matrix (types I, III, and V collagens) and in the basement membrane (type IV collagen). MATERIAL AND METHODS: Patients with 3 different types of hernias were included: Primary unilateral inguinal hernia (n = 17), multiple hernias defined as ≥3 hernias (n = 21), and incisional hernia...... degradation (C1M, C3M, C5M, and C4M) were measured in serum by validated, solid-phase competitive assays. RESULTS: In inguinal hernia patients, the turnover of the interstitial matrix collagens type III (P < .042) and V (P < .001) was decreased compared with controls, whereas the turnover of the basement...... membrane collagen type IV was increased (P < .001). In incisional hernia patients, the turnover of type V collagen was decreased (P = .048) and the turnover of type IV collagen was increased compared with the hernia-free controls (P < .001). CONCLUSION: Hernia patients demonstrated systemically altered...

  16. Tenascin-x deficiency mimics ehlers-danlos syndrome in mice through alteration of collagen deposition

    Energy Technology Data Exchange (ETDEWEB)

    Mao, J.R.; Taylor, G.; Dean, W.B.; Wagner, D.R.; Afzal, V.; Lotz, J.C.; Rubin, E.M.; Bristow, J.

    2002-03-01

    Tenascin-X is a large extracellular matrix protein of unknown function1-3. Tenascin-X deficiency in humans is associated with Ehlers-Danlos syndrome4,5, a generalized connective tissue disorder resulting from altered metabolism of the fibrillar collagens6. Because TNXB is the first Ehlers-Danlos syndrome gene that does not encode a fibrillar collagen or collagen-modifying enzyme7-14, we suggested that tenascin-X might regulate collagen synthesis or deposition15. To test this hypothesis, we inactivated Tnxb in mice. Tnxb-/- mice showed progressive skin hyperextensibility, similar to individuals with Ehlers-Danlos syndrome. Biomechanical testing confirmed increased deformability and reduced tensile strength of their skin. The skin of Tnxb-/- mice was histologically normal, but its collagen content was significantly reduced. At the ultrastructural level, collagen fibrils of Tnxb-/- mice were of normal size and shape, but the density of fibrils in their skin was reduced, commensurate with the reduction in collagen content. Studies of cultured dermal fibroblasts showed that although synthesis of collagen I by Tnxb-/- and wildtype cells was similar, Tnxb-/- fibroblasts failed to deposit collagen I into cell-associated matrix. This study confirms a causative role for TNXB in human Ehlers-Danlos syndrome and suggests that tenascin-X is an essential regulator of collagen deposition by dermal fibroblasts.

  17. Three-dimensional echocardiography

    Energy Technology Data Exchange (ETDEWEB)

    Buck, Thomas [University Hospital Essen (Germany). West German Heart Center; Franke, Andreas [Klinikum Region Hannover - Klinikum Siloah, Hannover (Germany). Dept. of Cardiology, Angiology and Intensive Care Medicine; Monaghan, Mark J. (eds.) [King' s College Hospital, London (United Kingdom)

    2011-07-01

    Presents tips and tricks for beginners and experts Provides educational material for 3D training courses Features comprehensively illustrated cases Includes an accompanying DVD with video clips of all sample cases Three-dimensional echocardiography is the most recent fundamental advancement in echocardiography. Since real-time 3D echocardiography became commercially available in 2002, it has rapidly been accepted in echo labs worldwide. This book covers all clinically relevant aspects of this fascinating new technology, including a comprehensive explanation of its basic principles, practical aspects of clinical application, and detailed descriptions of specific uses in the broad spectrum of clinically important heart disease. The book was written by a group of well-recognized international experts in the field, who have not only been involved in the scientific and clinical evolution of 3D echocardiography since its inception but are also intensively involved in expert training courses. As a result, the clear focus of this book is on the practical application of 3D echocardiography in daily clinical routine with tips and tricks for both beginners and experts, accompanied by more than 150 case examples comprehensively illustrated in more than 800 images and more than 500 videos provided on a DVD. In addition to an in-depth review of the most recent literature on real-time 3D echocardiography, this book represents an invaluable reference work for beginners and expert users of 3D echocardiography. - Tips and tricks for beginners and experts - Educational material for 3D training courses - Comprehensively illustrated cases - DVD with video clips of all sample cases.

  18. Three-dimensional echocardiography

    International Nuclear Information System (INIS)

    Presents tips and tricks for beginners and experts Provides educational material for 3D training courses Features comprehensively illustrated cases Includes an accompanying DVD with video clips of all sample cases Three-dimensional echocardiography is the most recent fundamental advancement in echocardiography. Since real-time 3D echocardiography became commercially available in 2002, it has rapidly been accepted in echo labs worldwide. This book covers all clinically relevant aspects of this fascinating new technology, including a comprehensive explanation of its basic principles, practical aspects of clinical application, and detailed descriptions of specific uses in the broad spectrum of clinically important heart disease. The book was written by a group of well-recognized international experts in the field, who have not only been involved in the scientific and clinical evolution of 3D echocardiography since its inception but are also intensively involved in expert training courses. As a result, the clear focus of this book is on the practical application of 3D echocardiography in daily clinical routine with tips and tricks for both beginners and experts, accompanied by more than 150 case examples comprehensively illustrated in more than 800 images and more than 500 videos provided on a DVD. In addition to an in-depth review of the most recent literature on real-time 3D echocardiography, this book represents an invaluable reference work for beginners and expert users of 3D echocardiography. - Tips and tricks for beginners and experts - Educational material for 3D training courses - Comprehensively illustrated cases - DVD with video clips of all sample cases.

  19. Three dimensional energy profile:

    International Nuclear Information System (INIS)

    The provision of adequate, reliable, and affordable energy has been considered as a cornerstone of development. More than one-third of the world's population has a very limited access to modern energy services and suffers from its various negative consequences. Researchers have been exploring various dimensions of household energy use in order to design strategies to provide secure access to modern energy services. However, despite more than three decades of effort, our understanding of household energy use patterns is very limited, particularly in the context of rural regions of the developing world. Through this paper, the past and the current trends in the field of energy analysis are investigated. The literature on rural energy and energy transition in developing world has been explored and the factors affecting households' decisions on energy use are listed. The and the factors affecting households' decisions on energy use are listed. The gaps identified in the literature on rural household energy analysis provide a basis for developing an alternative model that can create a more realistic view of household energy use. The three dimensional energy profile is presented as a new conceptual model for assessment of household energy use. This framework acts as a basis for building new theoretical and empirical models of rural household energy use. - Highlights: ► Reviews literature on household energy, energy transitions and decision-making in developing countries. ► Identifies gaps in rural household energy analysis and develops a new conceptual framework. ► The 3-d energy profile provides a holistic view of household energy system characteristics. ► Illustrates the use of the framework for understanding household energy transitions.

  20. Three-dimensional ICT reconstruction

    International Nuclear Information System (INIS)

    The three-dimensional ICT reconstruction method is the hot topic of recent ICT technology research. In the context, qualified visual three-dimensional ICT pictures are achieved through multi-piece two-dimensional images accumulation by, combining with thresholding method and linear interpolation. Different direction and different position images of the reconstructed pictures are got by rotation and interception respectively. The convenient and quick method is significantly instructive to more complicated three-dimensional reconstruction of ICT images. (authors)

  1. Modification of collagen IV by glucose or methylglyoxal alters distinct mesangial cell functions.

    Science.gov (United States)

    Pozzi, Ambra; Zent, Roy; Chetyrkin, Sergei; Borza, Corina; Bulus, Nada; Chuang, Peale; Chen, Dong; Hudson, Billy; Voziyan, Paul

    2009-10-01

    Diabetic nephropathy (DN) affects both glomerular cells and the extracellular matrix (ECM), yet the pathogenic mechanisms involving cell-matrix interactions are poorly understood. Glycation alters integrin-dependent cell-ECM interactions, and perturbation of these interactions results in severe renal pathology in diabetic animals. Here, we investigated how chemical modifications of the ECM by hyperglycemia and carbonyl stress, two major features of the diabetic milieu, affect mesangial cell functions. Incubation of collagen IV with pathophysiological levels of either the carbonyl compound methylglyoxal (MGO) or glucose resulted in modification of arginine or lysine residues, respectively. Mouse mesangial cells plated on MGO-modified collagen IV showed decreased adhesion and migration. Cells plated on glucose-modified collagen IV showed reduced proliferation and migration and increased collagen IV production. Inhibiting glucose-mediated oxidative modification of collagen IV lysine residues rescued the alterations in cell growth, migration, and collagen synthesis. We propose that diabetic ECM affects mesangial cell functions via two distinct mechanisms: modification of arginine residues by MGO inhibits cell adhesion, whereas oxidative modification of lysine residues by glucose inhibits cell proliferation and increases collagen IV production. These mechanisms may contribute to mesangial cell hypertrophy and matrix expansion in DN. PMID:19608705

  2. Correlative nonlinear optical microscopy and infrared nanoscopy reveals collagen degradation in altered parchments

    Science.gov (United States)

    Latour, Gaël; Robinet, Laurianne; Dazzi, Alexandre; Portier, François; Deniset-Besseau, Ariane; Schanne-Klein, Marie-Claire

    2016-05-01

    This paper presents the correlative imaging of collagen denaturation by nonlinear optical microscopy (NLO) and nanoscale infrared (IR) spectroscopy to obtain morphological and chemical information at different length scales. Such multiscale correlated measurements are applied to the investigation of ancient parchments, which are mainly composed of dermal fibrillar collagen. The main issue is to characterize gelatinization, the ultimate and irreversible alteration corresponding to collagen denaturation to gelatin, which may also occur in biological tissues. Key information about collagen and gelatin signatures is obtained in parchments and assessed by characterizing the denaturation of pure collagen reference samples. A new absorbing band is observed near the amide I band in the IR spectra, correlated to the onset of fluorescence signals in NLO images. Meanwhile, a strong decrease is observed in Second Harmonic signals, which are a structural probe of the fibrillar organization of the collagen at the micrometer scale. NLO microscopy therefore appears as a powerful tool to reveal collagen degradation in a non-invasive way. It should provide a relevant method to assess or monitor the condition of collagen-based materials in museum and archival collections and opens avenues for a broad range of applications regarding this widespread biological material.

  3. Three dimensional MEMS supercapacitors

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Wei

    2011-10-15

    The overall objective of this research is to achieve compact supercapacitors with high capacitance, large power density, and long cycle life for using as micro power sources to drive low power devices and sensors. The main shortcoming of supercapacitors as a power source is that its energy density typically is about 1/10 of that of batteries. To achieve compact supercapacitors of large energy density, supercapacitors must be developed with high capacitance and power density which are mainly depended on the effective surface area of the electrodes of the supercapacitors. Many studies have been done to increase the effective surface area by modifying the electrode materials, however, much less investigations are focus on machining the electrodes. In my thesis work, micro- and nano-technologies are applied as technology approaches for machining the electrodes with three dimensional (3D) microstructures. More specific, Micro-electro-mechanical system (MEMS) fabrication process flow, which integrates the key process such as LIGA-like (German acronym for Lithographie, Galvanoformung, Abformung, which mean Lithography, Electroplating and Molding) technology or DRIE (deep reactive ion etching), has been developed to enable innovative designs of 3D MEMS supercapacitors which own the electrodes of significantly increased geometric area. Two types of 3D MEMS supercapcitors, based on LIGA-like and DRIE technology respectively, were designed and successfully created. The LIGA-like based 3D MEMS supercapacitor is with an interdigital 3D structure, and consists of silicon substrate, two electroplated nickel current collectors, two PPy (poly pyrrole) electrodes, and solid state electrolyte. The fabrication process flow developed includes the flowing key processes, SU-8 lithography, nickel electroplating, PPy polymerization and solid state electrolyte coating. Electrochemical tests showed that the single electrode of the supercapacitor has the specific capacitance of 0.058 F cm-2

  4. Alterations of Dermal Connective Tissue Collagen in Diabetes: Molecular Basis of Aged-Appearing Skin

    Science.gov (United States)

    Argyropoulos, Angela J.; Robichaud, Patrick; Balimunkwe, Rebecca Mutesi; Fisher, Gary J.; Hammerberg, Craig; Yan, Yan

    2016-01-01

    Alterations of the collagen, the major structural protein in skin, contribute significantly to human skin connective tissue aging. As aged-appearing skin is more common in diabetes, here we investigated the molecular basis of aged-appearing skin in diabetes. Among all known human matrix metalloproteinases (MMPs), diabetic skin shows elevated levels of MMP-1 and MMP-2. Laser capture microdissection (LCM) coupled real-time PCR indicated that elevated MMPs in diabetic skin were primarily expressed in the dermis. Furthermore, diabetic skin shows increased lysyl oxidase (LOX) expression and higher cross-linked collagens. Atomic force microscopy (AFM) further indicated that collagen fibrils were fragmented/disorganized, and key mechanical properties of traction force and tensile strength were increased in diabetic skin, compared to intact/well-organized collagen fibrils in non-diabetic skin. In in vitro tissue culture system, multiple MMPs including MMP-1 and MM-2 were induced by high glucose (25 mM) exposure to isolated primary human skin dermal fibroblasts, the major cells responsible for collagen homeostasis in skin. The elevation of MMPs and LOX over the years is thought to result in the accumulation of fragmented and cross-linked collagen, and thus impairs dermal collagen structural integrity and mechanical properties in diabetes. Our data partially explain why old-looking skin is more common in diabetic patients. PMID:27104752

  5. Activation of PPARs α, β/δ, and γ Impairs TGF-β1-Induced Collagens' Production and Modulates the TIMP-1/MMPs Balance in Three-Dimensional Cultured Chondrocytes

    Directory of Open Access Journals (Sweden)

    Paul-Emile Poleni

    2010-01-01

    Full Text Available Background and Purpose. We investigated the potency of Peroxisome Proliferators-Activated Receptors (PPARs α, β/δ, and γ agonists to modulate Transforming Growth Factor-β1 (TGF-β1- induced collagen production or changes in Tissue Inhibitor of Matrix Metalloproteinase- (TIMP- 1/Matrix Metalloproteinase (MMP balance in rat chondrocytes embedded in alginate beads. Experimental Approach. Collagen production was evaluated by quantitative Sirius red staining, while TIMP-1 protein levels and global MMP (-1, -2, -3, -7, and -9 or specific MMP-13 activities were measured by ELISA and fluorigenic assays in culture media, respectively. Levels of mRNA for type II collagen, TIMP-1, and MMP-3 & 13 were quantified by real-time PCR. Key Results. TGF-β1 increased collagen deposition and type II collagen mRNA levels, while inducing TIMP-1 mRNA and protein expression. In contrast, it decreased global MMP or specific MMP-13 activities, while decreasing MMP-3 or MMP-13 mRNA levels. PPAR agonists reduced most of the effects of TGF-β1 on changes in collagen metabolism and TIMP-1/MMP balance in rat in a PPAR-dependent manner, excepted for Wy14643 on MMP activities. Conclusions and Implications. PPAR agonists reduce TGF-β1-modulated ECM turnover and inhibit chondrocyte activities crucial for collagen biosynthesis, and display a different inhibitory profile depending on selectivity for PPAR isotypes.

  6. Regional alterations of type I collagen in rat tibia induced by skeletal unloading

    Science.gov (United States)

    Shiiba, Masashi; Arnaud, Sara B.; Tanzawa, Hideki; Kitamura, Eiji; Yamauchi, Mitsuo

    2002-01-01

    Skeletal unloading induces loss of mineral density in weight-bearing bones that leads to inferior bone mechanical strength. This appears to be caused by a failure of bone formation; however, its mechanisms still are not well understood. The objective of this study was to characterize collagen, the predominant matrix protein in bone, in various regions of tibia of rats that were subjected to skeletal unloading by 4 weeks tail suspension. Sixteen male Sprague-Dawley rats (4 months old) were divided into tail suspension and ambulatory controls (eight rats each). After the tail suspension, tibias from each animal were collected and divided into five regions and collagen was analyzed. The collagen cross-linking and the extent of lysine (Lys) hydroxylation in unloaded bones were significantly altered in proximal epiphysis, diaphysis, and, in particular, proximal metaphysis but not in distal regions. The pool of immature/nonmineralized collagen measured by its extractability with a chaotropic solvent was significantly increased in proximal metaphysis. These results suggest that skeletal unloading induced an accumulation of post-translationally altered nonmineralized collagen and that these changes are bone region specific. These alterations might be caused by impaired osteoblastic function/differentiation resulting in a mineralization defect.

  7. Impermeability effects in three-dimensional vesicles

    International Nuclear Information System (INIS)

    We analyse the effects of the impermeability constraint on the equilibrium shapes of a three-dimensional vesicle hosting a rigid inclusion. A given alteration of the inclusion and/or vesicle parameters leads to shape modifications of different orders of magnitude, when applied to permeable or impermeable vesicles. Moreover, the enclosed-volume constraint wrecks the uniqueness of stationary equilibrium shapes, and gives rise to pear-shaped or stomatocyte-like vesicles

  8. Collagens

    OpenAIRE

    Gordon, Marion K.; Hahn, Rita A.

    2009-01-01

    The collagens represent a family of trimeric extracellular matrix molecules used by cells for structural integrity and other functions. The three α chains that form the triple helical part of the molecule are composed of repeating peptide triplets of glycine-X-Y. X and Y can be any amino acid but are often proline and hydroxyproline, respectively. Flanking the triple helical regions (i.e., Col domains) are non-glycine-X-Y regions, termed non-collagenous domains. These frequently contain recog...

  9. Three-dimensional stellarator codes

    OpenAIRE

    Garabedian, P. R.

    2002-01-01

    Three-dimensional computer codes have been used to develop quasisymmetric stellarators with modular coils that are promising candidates for a magnetic fusion reactor. The mathematics of plasma confinement raises serious questions about the numerical calculations. Convergence studies have been performed to assess the best configurations. Comparisons with recent data from large stellarator experiments serve to validate the theory.

  10. Three-dimensional Noncommutative Gravity

    OpenAIRE

    Banados, M.; Chandia, O.; Grandi, N.; Schaposnik, F. A.; G. A. Silva

    2001-01-01

    We formulate noncommutative three-dimensional (3d) gravity by making use of its connection with 3d Chern-Simons theory. In the Euclidean sector, we consider the particular example of topology $T^2 \\times R$ and show that the 3d black hole solves the noncommutative equations. We then consider the black hole on a constant U(1) background and show that the black hole charges (mass and angular momentum) are modified by the presence of this background.

  11. Three-dimensional obstetric ultrasound.

    Science.gov (United States)

    Tache, Veronique; Tarsa, Maryam; Romine, Lorene; Pretorius, Dolores H

    2008-04-01

    Three-dimensional ultrasound has gained a significant popularity in obstetrical practice in recent years. The advantage of this modality in some cases is in question, however. This article provides a basic review of volume acquisition, mechanical positioning, and display modalities. Multiple uses of this technique in obstetrical care including first trimester applications and its utility in clarification of fetal anatomy such as brain, face, heart, and skeleton is discussed. PMID:18450140

  12. Three-dimensional coronary angiography

    Science.gov (United States)

    Suurmond, Rolf; Wink, Onno; Chen, James; Carroll, John

    2005-04-01

    Three-Dimensional Coronary Angiography (3D-CA) is a novel tool that allows clinicians to view and analyze coronary arteries in three-dimensional format. This will help to find accurate length estimates and to find the optimal viewing angles of a lesion based on the three-dimensional vessel orientation. Various advanced algorithms are incorporated in this 3D processing utility including 3D-RA calibration, ECG phase selection, 2D vessel extraction, and 3D vessel modeling into a utility with optimized workflow and ease-of-use features, which is fully integrated in the environment of the x-ray catheterization lab. After the 3D processing, the 3D vessels can be viewed and manipulated interactively inside the operating room. The TrueView map provides a quick overview of gantry angles with optimal visualization of a single or bifurcation lesion. Vessel length measurements can be performed without risk of underestimating a vessel segment due to foreshortening. Vessel cross sectional diameters can also be measured. Unlike traditional, projection-based quantitative coronary analysis, the additional process of catheter calibration is not needed for diameter measurements. Validation studies show a high reproducibility of the measurements, with little user dependency.

  13. Three-dimensional cavity calculations

    International Nuclear Information System (INIS)

    The existence of a code that solves for the resonant electromagnetic modes of oscillation in arbitrarily-shaped three-dimensional cavities opens new possibilities in rf-structure analysis and research. The URMEL-3D code, the product of a multi-year collaboration between DESY, KFA-Juelich, and Los Alamos, has been used in some exploratory studies to determine the feasibility of using a 3-D code to calculate the properties of several practical rf structures. The results are reported here for three cases: the jungle gym, two coupled cavities, and a waveguide-cavity coupling problem

  14. Three-dimensional vision system

    International Nuclear Information System (INIS)

    This paper presents a model-based three-dimensional (3-D) object recognition system for an autonomous robot. 3-D information is reconstructed by means of passive trinocular stereo vision. 3-D physical edges are then extracted and linked to obtain scene description features. The representations of 3-D objects are built by using an extended solid model. Shape matching is performed by matching prominent features with those of stored models. The results of partial shape matching are used to determine the orientation and the location of the object in 3-D space. Experimental results using a real object show that the system is effective. (author)

  15. Probing Three-dimensional Collective Cancer Invasion with DIGME

    OpenAIRE

    Alobaidi, Amani A.; Sun, Bo

    2016-01-01

    Multicellular migration and pattern formation play important roles in developmental biology, cancer metastasis and wound healing. To understand the collective cell dynamics in three dimensional extracellular matrix (ECM), we have developed a simple and mechanical-based strategy, Diskoid In Geometrically Micropatterned ECM (DIGME). DIGME allows easy engineering of the shape of 3-D tissue organoid, the mesoscale ECM heterogeneity, and the fiber alignment of collagen-based ECM all at the same ti...

  16. Three-dimensional MR movies

    International Nuclear Information System (INIS)

    This paper reports on a subsecond MR tomography technique developed that uses imaging times of less than 200 msec. Three-dimensional (3D) imaging is possible in less than 11 seconds. The purpose of this report is to show 3D MR tomographic movies of the beating heart and parts of the abdomen. A whole-body 2-T system (Bruker Medspec) has been used in combination with fast switching gradient coils to study healthy volunteers. The 3D matrix was 128 x 128 x 32. The sequence has been used in combination with radio frequency inversion pulses to give T1 contrast and with a 90 degrees--180 degrees-90 degrees prepulse sequence to give T2 contrast. The authors measured 3D movies of the heart by repeating the 3D image acquisition using different electrocardiographic (ECG) trigger delays

  17. Three-dimensional homogeneous generalized Ricci solitons

    OpenAIRE

    Calvaruso, Giovanni

    2015-01-01

    We study three-dimensional generalized Ricci solitons, both in Riemannian and Lorentzian settings. We shall determine their homogeneous models, classifying left-invariant generalized Ricci solitons on three-dimensional Lie groups.

  18. Three-Dimensional Ultrasound in Cerebrovascular Evaluation

    OpenAIRE

    Jurašić, Miljenka-Jelena; Zavoreo, Iris; Demarin, Vida

    2006-01-01

    Three-dimensional ultrasound has started developing in the fifth decade of the last century using numerous imaging innovations. For the exploration of extracranial circulation, three-dimensional ultrasound is used primarily on carotid arteries that are easy to access due to their anatomical position. In the evaluation of intracranial circulation, three-dimensionality can be achieved only partially due to the size of the bony window that prevents probe movement in all 360°. Three-dimensional u...

  19. Three dimensional magnetic abacus memory

    Science.gov (United States)

    Zhang, Shilei; Zhang, Jingyan; Baker, Alexander A.; Wang, Shouguo; Yu, Guanghua; Hesjedal, Thorsten

    2014-08-01

    Stacking nonvolatile memory cells into a three-dimensional matrix represents a powerful solution for the future of magnetic memory. However, it is technologically challenging to access the data in the storage medium if large numbers of bits are stacked on top of each other. Here we introduce a new type of multilevel, nonvolatile magnetic memory concept, the magnetic abacus. Instead of storing information in individual magnetic layers, thereby having to read out each magnetic layer separately, the magnetic abacus adopts a new encoding scheme. It is inspired by the idea of second quantisation, dealing with the memory state of the entire stack simultaneously. Direct read operations are implemented by measuring the artificially engineered `quantised' Hall voltage, each representing a count of the spin-up and spin-down layers in the stack. This new memory system further allows for both flexible scaling of the system and fast communication among cells. The magnetic abacus provides a promising approach for future nonvolatile 3D magnetic random access memory.

  20. True three-dimensional camera

    Science.gov (United States)

    Kornreich, Philipp; Farell, Bart

    2013-01-01

    An imager that can measure the distance from each pixel to the point on the object that is in focus at the pixel is described. This is accomplished by short photo-conducting lightguides at each pixel. In the eye the rods and cones are the fiber-like lightguides. The device uses ambient light that is only coherent in spherical shell-shaped light packets of thickness of one coherence length. Modern semiconductor technology permits the construction of lightguides shorter than a coherence length of ambient light. Each of the frequency components of the broad band light arriving at a pixel has a phase proportional to the distance from an object point to its image pixel. Light frequency components in the packet arriving at a pixel through a convex lens add constructively only if the light comes from the object point in focus at this pixel. The light in packets from all other object points cancels. Thus the pixel receives light from one object point only. The lightguide has contacts along its length. The lightguide charge carriers are generated by the light patterns. These light patterns, and thus the photocurrent, shift in response to the phase of the input signal. Thus, the photocurrent is a function of the distance from the pixel to its object point. Applications include autonomous vehicle navigation and robotic vision. Another application is a crude teleportation system consisting of a camera and a three-dimensional printer at a remote location.

  1. Three dimensional imaging of otoliths

    International Nuclear Information System (INIS)

    Otoliths are small structures in fish ears made of calcium carbonate which carry a record of the environment in which the fish live. Traditionally, in order to study their microchemistry by a scanning technique such as PIXE the otoliths have been either ground down by hand or thin sectioned to expose the otolith core. However this technique is subject to human error in judging the core position. In this study we have scanned successive layers of otoliths 50 and 100 μm apart by removing the otolith material in a lapping machine which can be set to a few μm precision. In one study by comparing data from otoliths from the two ears of a freshwater species we found that polishing by hand could miss the core and thus give misleading results as to the life cycle of the fish. In another example we showed detail in a marine species which could be used to build a three dimensional picture of the Sr distribution. (author)

  2. Type Ⅰ collagen secreted by lung cancer cells promotes cancer cell growth in a three-dimensional culture system%肺癌细胞自分泌collagen Ⅰ在三维培养中促进肺癌细胞的生长

    Institute of Scientific and Technical Information of China (English)

    李江超; 李小妹; 兰天; 亓翠玲; 何晓东; 杨弘; 李焱; 王丽京; 关新元

    2014-01-01

    目的 研究肺癌细胞自分泌的胶原Ⅰ型(collagen Ⅰ)在肺癌细胞三维培养的作用.方法 通过免疫组化和RT-PCR证实肺癌细胞表达collagen Ⅰ;采用sh-collagen Ⅰ方法干扰肺癌细胞的表达,正常肺癌细胞作为对照组;用成纤维细胞的上清液刺激肿瘤,RT-PCR检测collagen Ⅰ的表达.结果 肺癌细胞分泌collagen Ⅰ;发现敲除collagen Ⅰ的肺癌细胞的三维生长受到限制:其生长率下降,三维培养中克隆形成减少.采用成纤维细胞培养细胞上清液刺激肿瘤细胞,肺癌肿瘤细胞自分泌的collagen Ⅰ表达发生改变,肿瘤自分泌的collagen Ⅰ可以维持自身生长的需要并受到微环境中非细胞外基质的调控.结论 肺癌细胞自分泌的collagen Ⅰ对肿瘤的生长有着重要作用.

  3. Enalapril alters the formation of the collagen matrix in spontaneously hypertensive rats

    Directory of Open Access Journals (Sweden)

    Bomfim Alfredo de Souza

    2003-01-01

    Full Text Available OBJECTIVE: To assess the effect of the inhibition of the angiotensin-converting enzyme on the collagen matrix (CM of the heart of newborn spontaneously hypertensive rats (SHR during embryonic development. METHODS: The study comprised the 2 following groups of SHR (n=5 each: treated group - rats conceived from SHR females treated with enalapril maleate (15 mg. kg-1.day-1 during gestation; and nontreated group - offspring of nontreated females. The newborns were euthanized within the first 24 hours after birth and their hearts were removed and processed for histological study. Three fields per animal were considered for computer-assisted digital analysis and determination of the volume densities (Vv of the nuclei and CM. The images were segmented with the aid of Image Pro Plus® 4.5.029 software (Media Cybernetics. RESULTS: No difference was observed between the treated and nontreated groups in regard to body mass, cardiac mass, and the relation between cardiac and body mass. A significant reduction in the Vv[matrix] and a concomitant increase in the Vv[nuclei] were observed in the treated group as compared with those in the nontreated group. CONCLUSION: The treatment with enalapril of hypertensive rats during pregnancy alters the collagen content and structure of the myocardium of newborns.

  4. Induced Elastic Matrix Deposition Within Three-Dimensional Collagen Scaffolds

    OpenAIRE

    Venkataraman, Lavanya; Ramamurthi, Anand

    2011-01-01

    The structural stability of a cyclically distending elastic artery and the healthy functioning of vascular smooth muscle cells (SMCs) within are maintained by the presence of an intact elastic matrix and its principal protein, elastin. The accelerated degradation of the elastic matrix, which occurs in several vascular diseases, coupled with the poor ability of adult SMCs to regenerate lost elastin, can therefore adversely impact vascular homeostasis. Similarly, efforts to tissue engineer elas...

  5. Three-dimensional multifunctional optical coherence tomography for skin imaging

    Science.gov (United States)

    Li, En; Makita, Shuichi; Hong, Young-Joo; Kasaragod, Deepa; Sasaoka, Tomoko; Yamanari, Masahiro; Sugiyama, Satoshi; Yasuno, Yoshiaki

    2016-02-01

    Optical coherence tomography (OCT) visualizes cross-sectional microstructures of biological tissues. Recent developments of multifunctional OCT (MF-OCT) provides multiple optical contrasts which can reveal currently unknown tissue properties. In this contribution we demonstrate multifunctional OCT specially designed for dermatological investigation. And by utilizing it to measure four different body parts of in vivo human skin, three-dimensional scattering OCT, OCT angiography, polarization uniformity tomography, and local birefringence tomography images were obtained by a single scan. They respectively contrast the structure and morphology, vasculature, melanin content and collagen traits of the tissue.

  6. Three-dimensional perception of facial asymmetry.

    Science.gov (United States)

    Meyer-Marcotty, Philipp; Stellzig-Eisenhauer, Angelika; Bareis, Ute; Hartmann, Jutta; Kochel, Janka

    2011-12-01

    In orthodontic diagnosis, facial symmetry is important. The aim of the present study was to analyse the perception of various degrees of facial asymmetry exhibited by carefully designed virtual three-dimensional (3D) material. Three groups of raters (30 orthodontists, 30 maxillofacial surgeons, and 30 laymen) rated, using a six-point scale, the degree of asymmetry of eight randomly presented 3D faces exhibiting incremental soft tissue alterations. The faces were created by gradually transforming the nose or chin in increments of 2 mm away from the computed symmetry plane. Differences between the groups in analysis of facial asymmetry, the rating of facial stimulus, and right and left facial asymmetry were determined using a t-test. The results demonstrated that raters' profession did not influence the point at which they identified asymmetry. Even laymen were able to detect asymmetries when located near the midline of 3D faces. All raters identified asymmetries of the nose as more negative than those of the same degree of the chin. A left-sided deviation of the nose along the facial symmetry plane lead to a more negative rating of facial appearance, whereas a right-sided deviation of the chin was rated as less attractive. Nasal architecture plays a crucial role in the perception of symmetry. These findings provide clinicians with a greater understanding of how faces are perceived, a process which is of particular interest in treating orthognathic patients, and those with congenital anomalies. PMID:21355063

  7. Alteration of cellular behavior and response to PI3K pathway inhibition by culture in 3D collagen gels.

    Directory of Open Access Journals (Sweden)

    Brian Fallica

    Full Text Available Most investigations into cancer cell drug response are performed with cells cultured on flat (2D tissue culture plastic. Emerging research has shown that the presence of a three-dimensional (3D extracellular matrix (ECM is critical for normal cell behavior including migration, adhesion, signaling, proliferation and apoptosis. In this study we investigate differences between cancer cell signaling in 2D culture and a 3D ECM, employing real-time, live cell tracking to directly observe U2OS human osteosarcoma and MCF7 human breast cancer cells embedded in type 1 collagen gels. The activation of the important PI3K signaling pathway under these different growth conditions is studied, and the response to inhibition of both PI3K and mTOR with PI103 investigated. Cells grown in 3D gels show reduced proliferation and migration as well as reduced PI3K pathway activation when compared to cells grown in 2D. Our results quantitatively demonstrate that a collagen ECM can protect U2OS cells from PI103. Overall, our data suggests that 3D gels may provide a better medium for investigation of anti-cancer drugs than 2D monolayers, therefore allowing better understanding of cellular response and behavior in native like environments.

  8. Different assembly of type IV collagen on hydrophilic and hydrophobic substrata alters endothelial cells interaction

    Directory of Open Access Journals (Sweden)

    NM Coelho

    2010-06-01

    Full Text Available Considering the structural role of type IV collagen (Col IV in the assembly of the basement membrane (BM and the perspective of mimicking its organization for vascular tissue engineering purposes, we studied the adsorption pattern of this protein on model hydrophilic (clean glass and hydrophobic trichloro(octadecylsilane (ODS surfaces known to strongly affect the behavior of other matrix proteins. The amount of fluorescently labeled Col IV was quantified showing saturation of the surface for concentration of the adsorbing solution of about 50μg/ml, but with approximately twice more adsorbed protein on ODS. AFM studies revealed a fine – nearly single molecular size – network arrangement of Col IV on hydrophilic glass, which turns into a prominent and growing polygonal network consisting of molecular aggregates on hydrophobic ODS. The protein layer forms within minutes in a concentration-dependent manner. We further found that human umbilical vein endothelial cells (HUVEC attach less efficiently to the aggregated Col IV (on ODS, as judged by the significantly altered cell spreading, focal adhesions formation and the development of actin cytoskeleton. Conversely, the immunofluorescence studies for integrins revealed that the fine Col IV network formed on hydrophilic substrata is better recognized by the cells via both α1 and α2 heterodimers which support cellular interaction, apart from these on hydrophobic ODS where almost no clustering of integrins was observed.

  9. Altered stress fibers and integrin expression in the Malpighian epithelium of Drosophila type IV collagen mutants.

    Science.gov (United States)

    Kiss, András A; Popovics, Nikoletta; Szabó, Gábor; Csiszár, Katalin; Mink, Mátyás

    2016-06-01

    Basement membranes (BMs) are highly specialized extracellular matrices (ECMs) that provide support and polarization cues for epithelial cells. Proper adhesion to the BM is pivotal in epithelial cell function and survival. Type IV collagens are the predominant components of all types of BMs, that form an irregular, polygonal lattice and serve as a scaffold for numerous other BM components and BM-associated cells. Mutations in the ubiquitous human BM components COL4A1 and COL4A2 cause a multisystem disorder involving nephropathy. Affected patients develop renal dysfunction and chronic kidney failure with or without hematuria. Mouse Col4a1 and Col4a2 mutants recapitulate the human symptoms. In vertebrates, excretion is accomplished by the kidneys and by the Malpighian tubules in insects, including the fruit fly Drosophila. Our present results with dominant, temperature-sensitive mutation of the Drosophila col4a1 gene demonstrate altered integrin expression and amplified effects of mechanical stress on the Malpighian epithelial cytoskeleton. PMID:27077087

  10. Three Dimensional Optic Tissue Culture and Process

    Science.gov (United States)

    OConnor, Kim C. (Inventor); Spaulding, Glenn F. (Inventor); Goodwin, Thomas J. (Inventor); Aten, Laurie A. (Inventor); Francis, Karen M. (Inventor); Caldwell, Delmar R. (Inventor); Prewett, Tacey L. (Inventor); Fitzgerald, Wendy S. (Inventor)

    1999-01-01

    A process for artificially producing three-dimensional optic tissue has been developed. The optic cells are cultured in a bioireactor at low shear conditions. The tissue forms as normal, functional tissue grows with tissue organization and extracellular matrix formation.

  11. Three-Dimensional Statistics of Radio Polarimetry

    OpenAIRE

    McKinnon, Mark M.

    2003-01-01

    The measurement of radio polarization may be regarded as a three-dimensional statistical problem because the large photon densities at radio wavelengths allow the simultaneous detection of the three Stokes parameters which completely describe the radiation's polarization. The statistical nature of the problem arises from the fluctuating instrumental noise, and possibly from fluctuations in the radiation's polarization. A statistical model is used to derive the general, three-dimensional stati...

  12. Three dimensional diffusion calculations of nuclear reactors

    International Nuclear Information System (INIS)

    This work deals with the three dimensional calculation of nuclear reactors using the code TRITON. The purposes of the work were to perform three-dimensional computations of the core of the Soreq nuclear reactor and of the power reactor ZION and to validate the TRITON code. Possible applications of the TRITON code in Soreq reactor calculations and in power reactor research are suggested. (H.K.)

  13. Three-dimensional imaging modalities in endodontics

    OpenAIRE

    Mao, Teresa; Neelakantan, Prasanna

    2014-01-01

    Recent research in endodontics has highlighted the need for three-dimensional imaging in the clinical arena as well as in research. Three-dimensional imaging using computed tomography (CT) has been used in endodontics over the past decade. Three types of CT scans have been studied in endodontics, namely cone-beam CT, spiral CT, and peripheral quantitative CT. Contemporary endodontics places an emphasis on the use of cone-beam CT for an accurate diagnosis of parameters that cannot be visualize...

  14. Three-Dimensional Statistics of Radio Polarimetry

    CERN Document Server

    McKinnon, M M

    2003-01-01

    The measurement of radio polarization may be regarded as a three-dimensional statistical problem because the large photon densities at radio wavelengths allow the simultaneous detection of the three Stokes parameters which completely describe the radiation's polarization. The statistical nature of the problem arises from the fluctuating instrumental noise, and possibly from fluctuations in the radiation's polarization. A statistical model is used to derive the general, three-dimensional statistics that govern radio polarization measurements. The statistics are derived for specific cases of source-intrinsic polarization, with an emphasis on the orthogonal polarization modes in pulsar radio emission. The statistics are similar to those commonly found in other fields of the physical, biological, and Earth sciences. Given the highly variable linear and circular polarization of pulsar radio emission, an understanding of the three-dimensional statistics may be an essential prequisite to a thorough interpretation of...

  15. Vision in our three-dimensional world

    Science.gov (United States)

    2016-01-01

    Many aspects of our perceptual experience are dominated by the fact that our two eyes point forward. Whilst the location of our eyes leaves the environment behind our head inaccessible to vision, co-ordinated use of our two eyes gives us direct access to the three-dimensional structure of the scene in front of us, through the mechanism of stereoscopic vision. Scientific understanding of the different brain regions involved in stereoscopic vision and three-dimensional spatial cognition is changing rapidly, with consequent influences on fields as diverse as clinical practice in ophthalmology and the technology of virtual reality devices. This article is part of the themed issue ‘Vision in our three-dimensional world’. PMID:27269595

  16. Three-dimensional microbubble streaming flows

    Science.gov (United States)

    Rallabandi, Bhargav; Marin, Alvaro; Rossi, Massimiliano; Kaehler, Christian; Hilgenfeldt, Sascha

    2014-11-01

    Streaming due to acoustically excited bubbles has been used successfully for applications such as size-sorting, trapping and focusing of particles, as well as fluid mixing. Many of these applications involve the precise control of particle trajectories, typically achieved using cylindrical bubbles, which establish planar flows. Using astigmatic particle tracking velocimetry (APTV), we show that, while this two-dimensional picture is a useful description of the flow over short times, a systematic three-dimensional flow structure is evident over long time scales. We demonstrate that this long-time three-dimensional fluid motion can be understood through asymptotic theory, superimposing secondary axial flows (induced by boundary conditions at the device walls) onto the two-dimensional description. This leads to a general framework that describes three-dimensional flows in confined microstreaming systems, guiding the design of applications that profit from minimizing or maximizing these effects.

  17. Three-Dimensional Extended Bargmann Supergravity

    CERN Document Server

    Bergshoeff, Eric A

    2016-01-01

    We show that three-dimensional General Relativity, augmented with two vector fields, allows for a non-relativistic limit, different from the standard limit leading to Newtonian gravity, that results into a well-defined action which is of the Chern-Simons type. We show that this three-dimensional `Extended Bargmann Gravity', after coupling to matter, leads to equations of motion allowing a wider class of background geometries than the ones that one encounters in Newtonian gravity. We give the supersymmetric generalization of these results and point out an important application in the context of calculating partition functions of non-relativistic field theories using localization techniques.

  18. Three-Dimensional Robotic Vision System

    Science.gov (United States)

    Nguyen, Thinh V.

    1989-01-01

    Stereoscopy and motion provide clues to outlines of objects. Digital image-processing system acts as "intelligent" automatic machine-vision system by processing views from stereoscopic television cameras into three-dimensional coordinates of moving object in view. Epipolar-line technique used to find corresponding points in stereoscopic views. Robotic vision system analyzes views from two television cameras to detect rigid three-dimensional objects and reconstruct numerically in terms of coordinates of corner points. Stereoscopy and effects of motion on two images complement each other in providing image-analyzing subsystem with clues to natures and locations of principal features.

  19. A Three-Dimensional Conformal Field Theory

    OpenAIRE

    Guruswamy, S.; Rajeev, S. G.; Vitale, P.

    1994-01-01

    This talk is based on a recent paper$^{1}$ of ours. In an attempt to understand three-dimensional conformal field theories, we study in detail one such example --the large $N$ limit of the $O(N)$ non-linear sigma model at its non-trivial fixed point -- in the zeta function regularization. We study this on various three-dimensional manifolds of constant curvature of the kind $\\Sigma \\times R$ ($\\Sigma=S^1 \\times S^1, S^2, H^2$). This describes a quantum phase transition at zero temperature. We...

  20. Three-dimensional imaging in medicine: Holography

    International Nuclear Information System (INIS)

    Two holographic methods for three-dimensional imaging in medicine are presented. The methods can be applied on the base of various primary projection methods, especially those of nuclear medicine and roentgenology. This three-dimensional display, which is not bound to complicated technical equipments such as computers and graphic displays, can be performed easily at any place: in conference rooms, in surgical units etc. It may be of particular importance for the surgeon in order to visualize the site directly and in its real space dimensions. (orig.)

  1. Three-dimensional matrix fiber alignment modulates cell migration and MT1-MMP utility by spatially and temporally directing protrusions

    Science.gov (United States)

    Fraley, Stephanie I.; Wu, Pei-Hsun; He, Lijuan; Feng, Yunfeng; Krisnamurthy, Ranjini; Longmore, Gregory D.; Wirtz, Denis

    2015-10-01

    Multiple attributes of the three-dimensional (3D) extracellular matrix (ECM) have been independently implicated as regulators of cell motility, including pore size, crosslink density, structural organization, and stiffness. However, these parameters cannot be independently varied within a complex 3D ECM protein network. We present an integrated, quantitative study of these parameters across a broad range of complex matrix configurations using self-assembling 3D collagen and show how each parameter relates to the others and to cell motility. Increasing collagen density resulted in a decrease and then an increase in both pore size and fiber alignment, which both correlated significantly with cell motility but not bulk matrix stiffness within the range tested. However, using the crosslinking enzyme Transglutaminase II to alter microstructure independently of density revealed that motility is most significantly predicted by fiber alignment. Cellular protrusion rate, protrusion orientation, speed of migration, and invasion distance showed coupled biphasic responses to increasing collagen density not predicted by 2D models or by stiffness, but instead by fiber alignment. The requirement of matrix metalloproteinase (MMP) activity was also observed to depend on microstructure, and a threshold of MMP utility was identified. Our results suggest that fiber topography guides protrusions and thereby MMP activity and motility.

  2. Three-dimensional collinearly propagating solitons

    International Nuclear Information System (INIS)

    The generalized nonlinear Schrödinger equation is modified in order to describe three-dimensional solitons propagating collinearly with a constant velocity. One- and two-soliton solutions are obtained and analysed. When the frequencies of the respective solitons approach, then the effect of the repulsion of the solitons is observed. These solitons are proposed to model photons. (paper)

  3. Three-dimensional ion micro-tomography

    International Nuclear Information System (INIS)

    The technique of ion micro-tomography (IMT) provides three-dimensional distribution information about a sample's mass density and elemental composition. The required data are obtained by doing a scanning transmission ion microscopy (STIM) tomography experiment followed by a particle-induced X-ray emission (PIXE) tomography experiment. The experiment times have been vastly reduced now that data are collected with MicroDAS, the new fast data acquisition system. Moreover, the experiment is easier to perform because sample manipulation is automated via computer control. To obtain comparable spatial resolutions between the STIM and PIXE data, the PIXE tomography experiment is performed by implementing a large solid angle between the sample and X-ray detector. To correct for the inherent three-dimensional nature of such an experimental setup, a specially developed tomographic reconstruction technique is used to combine the STIM and PIXE tomography data sets to create an accurate quantitative tomogram of the sample. The efficacy of the entire IMT process is tested with a characterised 'standard' sample. The calculated data agree well with the quantitative and structural information known about the sample. To interpret the three-dimensional distribution information, a special volume rendering program is used to visualise various aspects of the tomogram. Each aspect is colour coded to facilitate the easy visualisation of multiple complex three-dimensional structures

  4. Three-Dimensional Messages for Interstellar Communication

    Science.gov (United States)

    Vakoch, Douglas A.

    One of the challenges facing independently evolved civilizations separated by interstellar distances is to communicate information unique to one civilization. One commonly proposed solution is to begin with two-dimensional pictorial representations of mathematical concepts and physical objects, in the hope that this will provide a foundation for overcoming linguistic barriers. However, significant aspects of such representations are highly conventional, and may not be readily intelligible to a civilization with different conventions. The process of teaching conventions of representation may be facilitated by the use of three-dimensional representations redundantly encoded in multiple formats (e.g., as both vectors and as rasters). After having illustrated specific conventions for representing mathematical objects in a three-dimensional space, this method can be used to describe a physical environment shared by transmitter and receiver: a three-dimensional space defined by the transmitter--receiver axis, and containing stars within that space. This method can be extended to show three-dimensional representations varying over time. Having clarified conventions for representing objects potentially familiar to both sender and receiver, novel objects can subsequently be depicted. This is illustrated through sequences showing interactions between human beings, which provide information about human behavior and personality. Extensions of this method may allow the communication of such culture-specific features as aesthetic judgments and religious beliefs. Limitations of this approach will be noted, with specific reference to ETI who are not primarily visual.

  5. Three-dimensional rf structure calculations

    International Nuclear Information System (INIS)

    The calculation of three-dimensional rf structures is rapidly approaching adolescence, after having been in its infancy for the last four years. This paper will show the kinds of calculations that are currently being performed in the frequency domain and is a companion paper to one in which time-domain calculations are described. 13 refs., 14 figs

  6. Three-dimensional power doppler imaging

    International Nuclear Information System (INIS)

    Three-dimensional (3-D) ultrasonographic imaging techniques have recently shown rapid development and their clinical application has begun to attract considerable attention. Power Doppler sonography is known to be more sensitive than color Doppler for detecting blood flow, and there is also less noise and clutter. This paper describes the basic principles and initial clinical experience of 3-D power Doppler sonography

  7. Three-dimensional broadband tunable terahertz metamaterials

    DEFF Research Database (Denmark)

    Fan, Kebin; Strikwerda, Andrew; Zhang, Xin;

    2013-01-01

    We present optically tunable magnetic three-dimensional (3D) metamaterials at terahertz (THz) frequencies which exhibit a tuning range of ~30% of the resonance frequency. This is accomplished by fabricating 3D array structures consisting of double-split-ring resonators (DSRRs) on silicon on...

  8. Three dimensional electrochemical system for neurobiological studies

    DEFF Research Database (Denmark)

    Vazquez, Patricia; Dimaki, Maria; Svendsen, Winnie Edith

    2009-01-01

    In this work we report a novel three dimensional electrode array for electrochemical measurements in neuronal studies. The main advantage of working with these out-of-plane structures is the enhanced sensitivity of the system in terms of measuring electrochemical changes in the environment of a c...

  9. Cohomology of real three-dimensional triquadrics

    Science.gov (United States)

    Krasnov, Vyacheslav A.

    2012-02-01

    We consider non-singular intersections of three real five-dimensional quadrics. They are referred to for brevity as real three-dimensional triquadrics. We calculate the dimensions of the cohomology spaces of triquadrics with coefficients in the field of two elements.

  10. Cohomology of real three-dimensional triquadrics

    Energy Technology Data Exchange (ETDEWEB)

    Krasnov, Vyacheslav A [P.G. Demidov Yaroslavl State University, Yaroslavl (Russian Federation)

    2012-02-28

    We consider non-singular intersections of three real five-dimensional quadrics. They are referred to for brevity as real three-dimensional triquadrics. We calculate the dimensions of the cohomology spaces of triquadrics with coefficients in the field of two elements.

  11. Corticosteroid administration alters the mechanical properties of isolated collagen fascicles in rat-tail tendon

    DEFF Research Database (Denmark)

    Haraldsson, B T; Aagaard, P; Crafoord-Larsen, D;

    2009-01-01

    L of 40 mg/mL mixed with 1.0 mL 9% saline (n=12), and (B) a control group that was injected with 9% saline (n=12). Three days after the injections, the animals were sacrificed and single individual collagen fascicles were collected and underwent displacement to failure. Corticosteroid administration...

  12. Three-dimensional dynamic display research

    Science.gov (United States)

    Yan, Gao Bin; Yu, Jia; Liu, Hui-ping; Wang, Tian; Wang, Jin-cheng

    2014-11-01

    This paper proposes a new method for three-dimensional dynamic holographic display that combines computer generated holography (CGH) and holographic stereogram. Theoretically, three-dimensional (3D) dynamic holographic display can be achieved by using CGH alone, however the application of CGH is still limited because large amounts of data processing and complex mathematical calculation of off-axis diffracted light field. A new method combining CGH and stereogram is proposed, since stereogram uses a set of 2D images instead of a 3D object, both the complexity of the calculation and the resolution requirements of spatial light modulator (SLM) is reduced. To prove the feasibility of this method, experiments of making hologram using this method is carried out and the result shows that 3D displaying with a view angle of 28 is achieved.

  13. SNAP - a three dimensional neutron diffusion code

    International Nuclear Information System (INIS)

    This report describes a one- two- three-dimensional multi-group diffusion code, SNAP, which is primarily intended for neutron diffusion calculations but can also carry out gamma calculations if the diffusion approximation is accurate enough. It is suitable for fast and thermal reactor core calculations and for shield calculations. SNAP can solve the multi-group neutron diffusion equations using finite difference methods. The one-dimensional slab, cylindrical and spherical geometries and the two-dimensional case are all treated as simple special cases of three-dimensional geometries. Numerous reflective and periodic symmetry options are available and may be used to reduce the number of mesh points necessary to represent the system. Extrapolation lengths can be specified at internal and external boundaries. (Author)

  14. Three dimensional digital imaging of environmental data

    International Nuclear Information System (INIS)

    The Environmental Sciences Section (ESS) of the Savannah River Laboratory has recently acquired the computer hardware (Silicon Graphics Personal Iris Workstations) and software (Dynamic Graphics, Interactive Surface and Volume Modeling) to perform three dimensional analysis of hydrogeologic data. Three dimensional digital imaging of environmental data is a powerful technique that can be used to incorporate field, analytical, and modeling results from geologic, hydrologic, ecologic, and chemical studies into a comprehensive model for visualization and interpretation. This report covers the contamination of four different sites of the Savannah River Plant. Each section of this report has a computer graphic display of the concentration of contamination in the groundwater and/or sediments of each site

  15. Three-dimensional imaging modalities in endodontics

    International Nuclear Information System (INIS)

    Recent research in endodontics has highlighted the need for three-dimensional imaging in the clinical arena as well as in research. Three-dimensional imaging using computed tomography (CT) has been used in endodontics over the past decade. Three types of CT scans have been studied in endodontics, namely cone-beam CT, spiral CT, and peripheral quantitative CT. Contemporary endodontics places an emphasis on the use of cone-beam CT for an accurate diagnosis of parameters that cannot be visualized on a two-dimensional image. This review discusses the role of CT in endodontics, pertaining to its importance in the diagnosis of root canal anatomy, detection of peri-radicular lesions, diagnosis of trauma and resorption, presurgical assessment, and evaluation of the treatment outcome

  16. Three-dimensional imaging modalities in endodontics

    Energy Technology Data Exchange (ETDEWEB)

    Mao, Teresa; Neelakantan, Prasanna [Dept. of Conservative Dentistry and Endodontics, Saveetha Dental College and Hospitals, Saveetha University, Chennai (India)

    2014-09-15

    Recent research in endodontics has highlighted the need for three-dimensional imaging in the clinical arena as well as in research. Three-dimensional imaging using computed tomography (CT) has been used in endodontics over the past decade. Three types of CT scans have been studied in endodontics, namely cone-beam CT, spiral CT, and peripheral quantitative CT. Contemporary endodontics places an emphasis on the use of cone-beam CT for an accurate diagnosis of parameters that cannot be visualized on a two-dimensional image. This review discusses the role of CT in endodontics, pertaining to its importance in the diagnosis of root canal anatomy, detection of peri-radicular lesions, diagnosis of trauma and resorption, presurgical assessment, and evaluation of the treatment outcome.

  17. Three-dimensional Imaging, Visualization, and Display

    CERN Document Server

    Javidi, Bahram; Son, Jung-Young

    2009-01-01

    Three-Dimensional Imaging, Visualization, and Display describes recent developments, as well as the prospects and challenges facing 3D imaging, visualization, and display systems and devices. With the rapid advances in electronics, hardware, and software, 3D imaging techniques can now be implemented with commercially available components and can be used for many applications. This volume discusses the state-of-the-art in 3D display and visualization technologies, including binocular, multi-view, holographic, and image reproduction and capture techniques. It also covers 3D optical systems, 3D display instruments, 3D imaging applications, and details several attractive methods for producing 3D moving pictures. This book integrates the background material with new advances and applications in the field, and the available online supplement will include full color videos of 3D display systems. Three-Dimensional Imaging, Visualization, and Display is suitable for electrical engineers, computer scientists, optical e...

  18. Dielectric spectroscopy for non-invasive monitoring of epithelial cell differentiation within three-dimensional scaffolds

    International Nuclear Information System (INIS)

    In this study, we introduce a cellular differentiation cellular model based on dielectric spectroscopy that characterizes epithelial differentiation processes. Non-invasive cellular monitoring was achieved within a three-dimensional microenvironment consisting of a cell-containing collagen I gel seeded onto microfabricated scaffolds. In this proof-of-concept investigation, Madin–Darby canine kidney cells were cultured within microfabricated, geometrically controlled scaffolds and allowed us to differentiate to hollow cyst-like structures. This transformation within the three-dimensional environment is monitored and characterized through dielectric spectroscopy while maintaining cell culture in vitro. (paper)

  19. Localization on three-dimensional manifolds

    CERN Document Server

    Willett, Brian

    2016-01-01

    In this review article we describe the localization of three dimensional N=2 supersymmetric theories on compact manifolds, including the squashed sphere, S^3_b, the lens space, S^3_b/Z_p, and S^2 x S^1. We describe how to write supersymmetric actions on these spaces, and then compute the partition functions and other supersymmetric observables by employing the localization argument. We briefly survey some applications of these computations.

  20. Three-dimensional photography by holography

    OpenAIRE

    Lunazzi, J. J.

    2007-01-01

    Color encoding of depth is shown to occur naturally in holograms that are reconstructed under white light illumination. It can be registered in a common color photograph, allowing a simple method of visual decoding by means of ordinary colored 3-D spectacles. The fundamental holographic equations and the photographic procedure required for maximum fidelity in three-dimensional reproduction are described. The result is a new kind of photograph that shows all of the views of the object in a con...

  1. Imaging unsteady three-dimensional transport phenomena

    Indian Academy of Sciences (India)

    K Muralidhar

    2014-01-01

    Careful and continuous measurements of flow, heat and mass transfer are required in quite a few contexts. Using appropriate light sources, it is possible to map velocity, temperature, and species concentration over a cross-section and as a function of time. Image formation in optical measurements may rely on scattering of radiation from particles. Alternatively, if the region of interest is transparent, refractive index would be a field variable and beam bending effects can be used to extract information about temperature and concentration of solutes dissolved in liquids. Time-lapsed images of light intensity can be used to determine fluid velocity. Though used originally for flow visualization, optical imaging has now emerged as a powerful tool for quantitative measurements. Optical methods that utilize the dependence of refractive index on concentration and temperature can be configured in many different ways. Three available routes considered are interferometry, schlieren imaging, and shadowgraph. Images recorded in these configurations can be analysed to yield time sequences of three-dimensional distributions of the transported variables. Optical methods are non-intrusive, inertia-free and can image cross-sections of the experimental apparatus. The image data can be jointly analysed with the physical laws governing transport and principles of image formation. Hence, with the experiment suitably carried out, three-dimensional physical domains with unsteady processes can be accommodated. Optical methods promise to breach the holy grail of measurements by extracting unsteady three-dimensional data in applications related to transport phenomena.

  2. Teaching and Assessing Three-Dimensional M

    Science.gov (United States)

    Bateman, Robert C., Jr.; Booth, Deborah; Sirochman, Rudy; Richardson, Jane; Richardson, David

    2002-05-01

    Structural concepts such as the exact arrangement of a protein in three dimensions are crucial to almost every aspect of biology and chemistry, yet most of us have not been educated in three-dimensional literacy and all of us need a great deal of help in order to perceive and to communicate structural information successfully. It is in the undergraduate biochemistry course where students learn most concepts of molecular structure pertinent to living systems. We are addressing the issue of three-dimensional structural literacy by having undergraduate students construct kinemages, which are plain text scripts derived from Protein Data Bank coordinate files that can be viewed with the program MAGE. These annotated, interactive, three-dimensional illustrations are designed to develop a molecular story and allow exploration in the world of that story. In the process, students become familiar with the structure-based scientific literature and the Protein Data Bank. Our assessment to date has shown that students perceive kinemage authorship to be more helpful in understanding protein structure than simply viewing prepared kinemages. In addition, students perceived kinemage authorship as being beneficial to their career and a significant motivation to learn biochemistry.

  3. Three-Dimensional Audio Client Library

    Science.gov (United States)

    Rizzi, Stephen A.

    2005-01-01

    The Three-Dimensional Audio Client Library (3DAudio library) is a group of software routines written to facilitate development of both stand-alone (audio only) and immersive virtual-reality application programs that utilize three-dimensional audio displays. The library is intended to enable the development of three-dimensional audio client application programs by use of a code base common to multiple audio server computers. The 3DAudio library calls vendor-specific audio client libraries and currently supports the AuSIM Gold-Server and Lake Huron audio servers. 3DAudio library routines contain common functions for (1) initiation and termination of a client/audio server session, (2) configuration-file input, (3) positioning functions, (4) coordinate transformations, (5) audio transport functions, (6) rendering functions, (7) debugging functions, and (8) event-list-sequencing functions. The 3DAudio software is written in the C++ programming language and currently operates under the Linux, IRIX, and Windows operating systems.

  4. Irradiation Alters MMP-2/TIMP-2 System and Collagen Type IV Degradation in Brain

    International Nuclear Information System (INIS)

    Purpose: Blood-brain barrier (BBB) disruption is one of the major consequences of radiation-induced normal tissue injury in the central nervous system. We examined the effects of whole-brain irradiation on matrix metalloproteinases (MMPs)/tissue inhibitors of metalloproteinases (TIMPs) and extracellular matrix (ECM) degradation in the brain. Methods and Materials: Animals received either whole-brain irradiation (a single dose of 10 Gy γ-rays or a fractionated dose of 40 Gy γ-rays, total) or sham-irradiation and were maintained for 4, 8, and 24 h following irradiation. mRNA expression levels of MMPs and TIMPs in the brain were analyzed by real-time reverse transcriptase-polymerase chain reaction (PCR). The functional activity of MMPs was measured by in situ zymography, and degradation of ECM was visualized by collagen type IV immunofluorescent staining. Results: A significant increase in mRNA expression levels of MMP-2, MMP-9, and TIMP-1 was observed in irradiated brains compared to that in sham-irradiated controls. In situ zymography revealed a strong gelatinolytic activity in the brain 24 h postirradiation, and the enhanced gelatinolytic activity mediated by irradiation was significantly attenuated in the presence of anti-MMP-2 antibody. A significant reduction in collagen type IV immunoreactivity was also detected in the brain at 24 h after irradiation. In contrast, the levels of collagen type IV were not significantly changed at 4 and 8 h after irradiation compared with the sham-irradiated controls. Conclusions: The present study demonstrates for the first time that radiation induces an imbalance between MMP-2 and TIMP-2 levels and suggests that degradation of collagen type IV, a major ECM component of BBB basement membrane, may have a role in the pathogenesis of brain injury.

  5. Irradiation Alters MMP-2/TIMP-2 System and Collagen Type IV Degradation in Brain

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Won Hee [School of Biomedical Engineering and Sciences, Virginia Polytechnic Institute and State University, Blacksburg, Virginia (United States); Warrington, Junie P.; Sonntag, William E. [Reynolds Oklahoma Center on Aging, Department of Geriatric Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma (United States); Lee, Yong Woo, E-mail: ywlee@vt.edu [School of Biomedical Engineering and Sciences, Virginia Polytechnic Institute and State University, Blacksburg, Virginia (United States); Department of Biomedical Sciences and Pathobiology, Virginia Polytechnic Institute and State University, Blacksburg, Virginia (United States)

    2012-04-01

    Purpose: Blood-brain barrier (BBB) disruption is one of the major consequences of radiation-induced normal tissue injury in the central nervous system. We examined the effects of whole-brain irradiation on matrix metalloproteinases (MMPs)/tissue inhibitors of metalloproteinases (TIMPs) and extracellular matrix (ECM) degradation in the brain. Methods and Materials: Animals received either whole-brain irradiation (a single dose of 10 Gy {gamma}-rays or a fractionated dose of 40 Gy {gamma}-rays, total) or sham-irradiation and were maintained for 4, 8, and 24 h following irradiation. mRNA expression levels of MMPs and TIMPs in the brain were analyzed by real-time reverse transcriptase-polymerase chain reaction (PCR). The functional activity of MMPs was measured by in situ zymography, and degradation of ECM was visualized by collagen type IV immunofluorescent staining. Results: A significant increase in mRNA expression levels of MMP-2, MMP-9, and TIMP-1 was observed in irradiated brains compared to that in sham-irradiated controls. In situ zymography revealed a strong gelatinolytic activity in the brain 24 h postirradiation, and the enhanced gelatinolytic activity mediated by irradiation was significantly attenuated in the presence of anti-MMP-2 antibody. A significant reduction in collagen type IV immunoreactivity was also detected in the brain at 24 h after irradiation. In contrast, the levels of collagen type IV were not significantly changed at 4 and 8 h after irradiation compared with the sham-irradiated controls. Conclusions: The present study demonstrates for the first time that radiation induces an imbalance between MMP-2 and TIMP-2 levels and suggests that degradation of collagen type IV, a major ECM component of BBB basement membrane, may have a role in the pathogenesis of brain injury.

  6. Second harmonic generation microscopy reveals altered collagen microstructure in usual interstitial pneumonia versus healthy lung

    OpenAIRE

    Kottmann, Robert Matthew; Sharp, Jesse; Owens, Kristina; Salzman, Peter; Xiao, Guang-Qian; Phipps, Richard P.; Sime, Patricia J.; Brown, Edward B.; Perry, Seth W.

    2015-01-01

    Background It is not understood why some pulmonary fibroses such as cryptogenic organizing pneumonia (COP) respond well to treatment, while others like usual interstitial pneumonia (UIP) do not. Increased understanding of the structure and function of the matrix in this area is critical to improving our understanding of the biology of these diseases and developing novel therapies. The objectives herein are to provide new insights into the underlying collagen- and matrix-related biological mec...

  7. Three-dimensional analysis of craniofacial bones using three-dimensional computer tomography

    International Nuclear Information System (INIS)

    Three-dimensional computer tomography (3DCT) was performed in patients with various diseases to visualize stereoscopically the deformity of the craniofacial bones. The data obtained were analyzed by the 3DCT analyzing system. A new coordinate system was established using the median sagittal plane of the face (a plane passing through sella, nasion and basion) on the three-dimensional image. Three-dimensional profilograms were prepared for detailed analysis of the deformation of craniofacial bones for cleft lip and palate, mandibular prognathia and hemifacial microsomia. For patients, asymmetry in the frontal view and twist-formed complicated deformities were observed, as well as deformity of profiles in the anteroposterior and up-and-down directions. A newly developed technique allows three-dimensional visualization of changes in craniofacial deformity. It would aid in determining surgical strategy, including crani-facial surgery and maxillo-facial surgery, and in evaluating surgical outcome. (N.K.)

  8. Three-dimensional analysis of craniofacial bones using three-dimensional computer tomography

    Energy Technology Data Exchange (ETDEWEB)

    Ono, Ichiro; Ohura, Takehiko; Kimura, Chu (Hokkaido Univ., Sapporo (Japan). School of Medicine) (and others)

    1989-08-01

    Three-dimensional computer tomography (3DCT) was performed in patients with various diseases to visualize stereoscopically the deformity of the craniofacial bones. The data obtained were analyzed by the 3DCT analyzing system. A new coordinate system was established using the median sagittal plane of the face (a plane passing through sella, nasion and basion) on the three-dimensional image. Three-dimensional profilograms were prepared for detailed analysis of the deformation of craniofacial bones for cleft lip and palate, mandibular prognathia and hemifacial microsomia. For patients, asymmetry in the frontal view and twist-formed complicated deformities were observed, as well as deformity of profiles in the anteroposterior and up-and-down directions. A newly developed technique allows three-dimensional visualization of changes in craniofacial deformity. It would aid in determining surgical strategy, including crani-facial surgery and maxillo-facial surgery, and in evaluating surgical outcome. (N.K.).

  9. Three dimensional illustrating - three-dimensional vision and deception of sensibility

    Directory of Open Access Journals (Sweden)

    Anita Gánóczy

    2009-03-01

    Full Text Available The wide-spread digital photography and computer use gave the opportunity for everyone to make three-dimensional pictures and to make them public. The new opportunities with three-dimensional techniques give chance for the birth of new artistic photographs. We present in detail the biological roots of three-dimensional visualization, the phenomena of movement parallax, which can be used efficiently in making three-dimensional graphics, the Zöllner- and Corridor-illusion. There are present in this paper the visual elements, which contribute to define a plane two-dimensional image in three-dimension: coherent lines, the covering, the measurement changes, the relative altitude state, the abatement of detail profusion, the shadings and the perspective effects of colors.

  10. Pulmonary connective tissue modifications induced by internal α-irradiation. II. Alterations of collagen and non collagen proteins biosynthesis following inhalation of plutonium 239 dioxide aerosol in rat

    International Nuclear Information System (INIS)

    Preliminary studies have shown that internal α irradiation following inhalation of plutonium 239 dioxide in rat increased collagen content in the lung. Effect was maximal at 200 days with the highest dose. This increase was found transient and collagen dropped back to control values after 400 days in rats with the same initial lung burden or the same total dose. A new increase was observed later on, largely related to oncoming death. Here, we have studied, simultaneously, content and biosynthesis of collagen and non collagen proteins, 200 d and 400 d after 239PuO2 inhalation (100-150 nCi ILB). The results confirmed a biphasic effect of inhaled 239PuO2 on the pulmonary connective tissue: a/ A significant increase (p < 0.01) of soluble non-collagen proteins correlated to a decrease of the insoluble fraction was observed 200 d after inhalation. Similar parameters were not significantly different in controls on irradiated rats after 400 days. b/ Soluble and non-soluble collagen contents increased by a factor of 3 and 1.5 respectively 200 d after inhalation. No effect after 400 d. c/ Biosynthesis of non-collagen connective tissue components were 2 to 5 lower than in controls at 400d. d/collagen biosynthesis was decreased by a factor between 4 and 6 for the soluble and insoluble fractions at 200 d but normal at 400 d

  11. Three-dimensional stereo by photometric ratios

    International Nuclear Information System (INIS)

    We present a methodology for corresponding a dense set of points on an object surface from photometric values for three-dimensional stereo computation of depth. The methodology utilizes multiple stereo pairs of images, with each stereo pair being taken of the identical scene but under different illumination. With just two stereo pairs of images taken under two different illumination conditions, a stereo pair of ratio images can be produced, one for the ratio of left-hand images and one for the ratio of right-hand images. We demonstrate how the photometric ratios composing these images can be used for accurate correspondence of object points. Object points having the same photometric ratio with respect to two different illumination conditions constitute a well-defined equivalence class of physical constraints defined by local surface orientation relative to illumination conditions. We formally show that for diffuse reflection the photometric ratio is invariant to varying camera characteristics, surface albedo, and viewpoint and that therefore the same photometric ratio in both images of a stereo pair implies the same equivalence class of physical constraints. The correspondence of photometric ratios along epipolar lines in a stereo pair of images under different illumination conditions is a correspondence of equivalent physical constraints, and the determination of depth from stereo can be performed. Whereas illumination planning is required, our photometric-based stereo methodology does not require knowledge of illumination conditions in the actual computation of three-dimensional depth and is applicable to perspective views. This technique extends the stereo determination of three-dimensional depth to smooth featureless surfaces without the use of precisely calibrated lighting. We demonstrate experimental depth maps from a dense set of points on smooth objects of known ground-truth shape, determined to within 1% depth accuracy

  12. Three-dimensional ultrasonic colloidal crystals

    Science.gov (United States)

    Caleap, Mihai; Drinkwater, Bruce W.

    2016-05-01

    Colloidal assembly represents a powerful method for the fabrication of functional materials. In this article, we describe how acoustic radiation forces can guide the assembly of colloidal particles into structures that serve as microscopic elements in novel acoustic metadevices or act as phononic crystals. Using a simple three-dimensional orthogonal system, we show that a diversity of colloidal structures with orthorhombic symmetry can be assembled with megahertz-frequency (MHz) standing pressure waves. These structures allow rapid tuning of acoustic properties and provide a new platform for dynamic metamaterial applications. xml:lang="fr"

  13. Three-dimensional lock and key colloids.

    Science.gov (United States)

    Wang, Yu; Wang, Yufeng; Zheng, Xiaolong; Yi, Gi-Ra; Sacanna, Stefano; Pine, David J; Weck, Marcus

    2014-05-14

    Colloids with well-defined multicavities are synthesized through the hydrolytic removal of silica cluster templates from organo-silica hybrid patchy particles. The geometry of the cavities stems from the originally assembled cluster templates, displaying well-defined three-dimensional symmetries, ranging from spherical, linear, triangular, tetrahedral, trigonal dipyramidal, octahedral, to pentagonal dipyramidal. The concave surface of the cavities is smooth, and the cavity shallowness and size can be varied. These particles with multicavities can act as "lock" particles with multiple "key holes". Up to n "key" particles can self-assemble into the lock particles via depletion interaction, resulting in multivalent, site-specific, reversible, and flexible bonding. PMID:24785203

  14. Three-dimensional positioning with optofluidic microscope

    DEFF Research Database (Denmark)

    Vig, Asger Laurberg; Marie, Rodolphe; Jensen, Eric;

    2010-01-01

    This paper reports on-chip based optical detection with three-dimensional spatial resolution by integration of an optofluidic microscope (OFM) in a microfluidic pinched flow fractionation (PFF) separation device. This setup also enables on-chip particle image velocimetry (PIV). The position in the...... conventional fluorescence microscope as readout. The size separated microspheres are detected by OFM with an accuracy of ≤ 0.92 μm. The position in the height of the channel and the velocity of the separated microspheres are detected with an accuracy of 1.4 μm and 0.08 mm/s respectively. Throughout the...

  15. Three Dimensional Double Layers in Magnetized Plasmas

    DEFF Research Database (Denmark)

    Jovanovic, D.; Lynov, Jens-Peter; Michelsen, Poul;

    1982-01-01

    Experimental results are presented which demonstrate the formation of fully three dimensional double layers in a magnetized plasma. The measurements are performed in a magnetized stationary plasma column with radius 1.5 cm. Double layers are produced by introducing an electron beam with radius 0.4...... cm along the magnetic field from one end of the column. The voltage drop across the double layer is found to be determined by the energy of the incoming electron beam. In general we find that the width of the double layer along the external magnetic field is determined by plasma density and beam...

  16. Three dimensional dilatonic gravity's rainbow: exact solutions

    CERN Document Server

    Hendi, Seyed Hossein; Panahiyan, Shahram

    2016-01-01

    Deep relations of dark energy scenario and string theory results with dilaton gravity, on one hand, and the connection between quantum gravity with gravity's rainbow, on the other hand, motivate us to consider three dimensional dilatonic black hole solutions in gravity's rainbow. We obtain two classes of the solutions which are polynomial and logarithmic forms. We also calculate conserved and thermodynamic quantities, and examine the first law of thermodynamics for both classes. In addition, we study thermal stability and show that one of the classes is thermally stable while the other one is unstable.

  17. Three-dimensional simulations of burning thermals

    Science.gov (United States)

    Aspden, Andy; Bell, John; Woosley, Stan

    2010-11-01

    Flame ignition in type Ia supernovae (SNe Ia) leads to isolated bubbles of burning buoyant fluid. As a bubble rises due to gravity, it becomes deformed by shear instabilities and transitions to a turbulent buoyant vortex ring. Morton, Taylor and Turner (1956) introduced the entrainment assumption, which can be applied to inert thermals. In this study, we use the entrainment assumption, suitably modified to account for burning, to predict the late-time asymptotic behaviour of these turbulent buoyant vortex rings in SNe Ia. The theory is validated against three- dimensional simulations with adaptive mesh refinement at effective resolutions up to 4096^3.

  18. Three-dimensional cooling of muons

    CERN Document Server

    Vsevolozhskaya, T A

    2000-01-01

    The simultaneous ionization cooling of muon beams in all three - the longitudinal and two transverse - directions is considered in a scheme, based on bent lithium lenses with dipole constituent of magnetic field in them, created by a special configuration of current-carrying rod. An analysis of three-dimensional cooling is performed with the use of kinetic equation method. Results of numerical calculation for a specific beam line configuration are presented together with results of computer simulation using the Moliere distribution to describe the Coulomb scattering and the Vavilov distribution used to describe the ionization loss of energy.

  19. Three-dimensional teletherapy treatment planning

    International Nuclear Information System (INIS)

    This thesis deals with physical/mathematical backgrounds of computerized teletherapy treatment planning. The subjects discussed in this thesis can be subdivided into three main categories: a) Three-dimensional treatment planning. A method is evaluated which can be used for the purpose of simulation and optimization of dose distributions in three dimensions. b) The use of Computed Tomography. The use of patient information obtained from Computed Tomography for the purpose of dose computations is evaluated. c) Dose computational models for photon- and electron beams. Models are evaluated which provide information regarding the way in which the radiation dose is distributed in the patient (viz. is absorbed and/or dispersed). (Auth.)

  20. Two component-three dimensional catalysis

    Science.gov (United States)

    Schwartz, Michael; White, James H.; Sammells, Anthony F.

    2002-01-01

    This invention relates to catalytic reactor membranes having a gas-impermeable membrane for transport of oxygen anions. The membrane has an oxidation surface and a reduction surface. The membrane is coated on its oxidation surface with an adherent catalyst layer and is optionally coated on its reduction surface with a catalyst that promotes reduction of an oxygen-containing species (e.g., O.sub.2, NO.sub.2, SO.sub.2, etc.) to generate oxygen anions on the membrane. The reactor has an oxidation zone and a reduction zone separated by the membrane. A component of an oxygen containing gas in the reduction zone is reduced at the membrane and a reduced species in a reactant gas in the oxidation zone of the reactor is oxidized. The reactor optionally contains a three-dimensional catalyst in the oxidation zone. The adherent catalyst layer and the three-dimensional catalyst are selected to promote a desired oxidation reaction, particularly a partial oxidation of a hydrocarbon.

  1. Three-dimensional image signals: processing methods

    Science.gov (United States)

    Schiopu, Paul; Manea, Adrian; Craciun, Anca-Ileana; Craciun, Alexandru

    2010-11-01

    Over the years extensive studies have been carried out to apply coherent optics methods in real-time processing, communications and transmission image. This is especially true when a large amount of information needs to be processed, e.g., in high-resolution imaging. The recent progress in data-processing networks and communication systems has considerably increased the capacity of information exchange. We describe the results of literature investigation research of processing methods for the signals of the three-dimensional images. All commercially available 3D technologies today are based on stereoscopic viewing. 3D technology was once the exclusive domain of skilled computer-graphics developers with high-end machines and software. The images capture from the advanced 3D digital camera can be displayed onto screen of the 3D digital viewer with/ without special glasses. For this is needed considerable processing power and memory to create and render the complex mix of colors, textures, and virtual lighting and perspective necessary to make figures appear three-dimensional. Also, using a standard digital camera and a technique called phase-shift interferometry we can capture "digital holograms." These are holograms that can be stored on computer and transmitted over conventional networks. We present some research methods to process "digital holograms" for the Internet transmission and results.

  2. On three-dimensional dilational elastic metamaterials

    International Nuclear Information System (INIS)

    Dilational materials are stable, three-dimensional isotropic auxetics with an ultimate Poisson's ratio of −1. Inspired by previous theoretical work, we design a feasible blueprint for an artificial material, a metamaterial, which approaches the ideal of a dilational material. The main novelty of our work is that we also fabricate and characterize corresponding metamaterial samples. To reveal all modes in the design, we calculate the phonon band structures. On this basis, using cubic symmetry we can unambiguously retrieve all different non-zero elements of the rank-four effective metamaterial elasticity tensor from which all effective elastic metamaterial properties follow. While the elastic properties and the phase velocity remain anisotropic, the effective Poisson's ratio indeed becomes isotropic and approaches −1 in the limit of small internal connections. This finding is also supported by independent, static continuum-mechanics calculations. In static experiments on macroscopic polymer structures fabricated by three-dimensional printing, we measure Poisson's ratios as low as −0.8 in good agreement with the theory. Microscopic samples are also presented. (paper)

  3. Three-dimensional flow in Kupffer's Vesicle

    CERN Document Server

    Montenegro-Johnson, Thomas D; Smith, David J; Lopes, Susana S

    2016-01-01

    Whilst many vertebrates appear externally left-right symmetric, the arrangement of internal organs is asymmetric. In zebrafish, the breaking of left-right symmetry is organised by Kupffer's Vesicle (KV): an approximately spherical, fluid-filled structure that begins to form in the embryo 10 hours post fertilisation. A crucial component of zebrafish symmetry breaking is the establishment of a cilia-driven fluid flow within KV. However, it is still unclear (a) how dorsal, ventral and equatorial cilia contribute to the global vortical flow, and (b) if this flow breaks left-right symmetry through mechanical transduction or morphogen transport. Fully answering these questions requires knowledge of the three-dimensional flow patterns within KV, which have not been quantified in previous work. In this study, we calculate and analyse the three-dimensional flow in KV. We consider flow from both individual and groups of cilia, and (a) find anticlockwise flow can arise purely from excess of cilia on the dorsal roof over...

  4. Multilineage differentiation of rhesus monkey embryonic stem cells in three-dimensional culture systems

    Science.gov (United States)

    Chen, Silvia S.; Revoltella, Roberto P.; Papini, Sandra; Michelini, Monica; Fitzgerald, Wendy; Zimmerberg, Joshua; Margolis, Leonid

    2003-01-01

    In the course of normal embryogenesis, embryonic stem (ES) cells differentiate along different lineages in the context of complex three-dimensional (3D) tissue structures. In order to study this phenomenon in vitro under controlled conditions, 3D culture systems are necessary. Here, we studied in vitro differentiation of rhesus monkey ES cells in 3D collagen matrixes (collagen gels and porous collagen sponges). Differentiation of ES cells in these 3D systems was different from that in monolayers. ES cells differentiated in collagen matrixes into neural, epithelial, and endothelial lineages. The abilities of ES cells to form various structures in two chemically similar but topologically different matrixes were different. In particular, in collagen gels ES cells formed gland-like circular structures, whereas in collagen sponges ES cells were scattered through the matrix or formed aggregates. Soluble factors produced by feeder cells or added to the culture medium facilitated ES cell differentiation into particular lineages. Coculture with fibroblasts in collagen gel facilitated ES cell differentiation into cells of a neural lineage expressing nestin, neural cell adhesion molecule, and class III beta-tubulin. In collagen sponges, keratinocytes facilitated ES cell differentiation into cells of an endothelial lineage expressing factor VIII. Exogenous granulocyte-macrophage colony-stimulating factor further enhanced endothelial differentiation. Thus, both soluble factors and the type of extracellular matrix seem to be critical in directing differentiation of ES cells and the formation of tissue-like structures. Three-dimensional culture systems are a valuable tool for studying the mechanisms of these phenomena.

  5. Open-Porous Hydroxyapatite Scaffolds for Three-Dimensional Culture of Human Adult Liver Cells

    Directory of Open Access Journals (Sweden)

    Anthony Finoli

    2016-01-01

    Full Text Available Liver cell culture within three-dimensional structures provides an improved culture system for various applications in basic research, pharmacological screening, and implantable or extracorporeal liver support. Biodegradable calcium-based scaffolds in such systems could enhance liver cell functionality by providing endothelial and hepatic cell support through locally elevated calcium levels, increased surface area for cell attachment, and allowing three-dimensional tissue restructuring. Open-porous hydroxyapatite scaffolds were fabricated and seeded with primary adult human liver cells, which were embedded within or without gels of extracellular matrix protein collagen-1 or hyaluronan. Metabolic functions were assessed after 5, 15, and 28 days. Longer-term cultures exhibited highest cell numbers and liver specific gene expression when cultured on hydroxyapatite scaffolds in collagen-1. Endothelial gene expression was induced in cells cultured on scaffolds without extracellular matrix proteins. Hydroxyapatite induced gene expression for cytokeratin-19 when cells were cultured in collagen-1 gel while culture in hyaluronan increased cytokeratin-19 gene expression independent of the use of scaffold in long-term culture. The implementation of hydroxyapatite composites with extracellular matrices affected liver cell cultures and cell differentiation depending on the type of matrix protein and the presence of a scaffold. The hydroxyapatite scaffolds enable scale-up of hepatic three-dimensional culture models for regenerative medicine applications.

  6. Open-Porous Hydroxyapatite Scaffolds for Three-Dimensional Culture of Human Adult Liver Cells

    Science.gov (United States)

    Schmelzer, Eva; Over, Patrick; Nettleship, Ian; Gerlach, Joerg C.

    2016-01-01

    Liver cell culture within three-dimensional structures provides an improved culture system for various applications in basic research, pharmacological screening, and implantable or extracorporeal liver support. Biodegradable calcium-based scaffolds in such systems could enhance liver cell functionality by providing endothelial and hepatic cell support through locally elevated calcium levels, increased surface area for cell attachment, and allowing three-dimensional tissue restructuring. Open-porous hydroxyapatite scaffolds were fabricated and seeded with primary adult human liver cells, which were embedded within or without gels of extracellular matrix protein collagen-1 or hyaluronan. Metabolic functions were assessed after 5, 15, and 28 days. Longer-term cultures exhibited highest cell numbers and liver specific gene expression when cultured on hydroxyapatite scaffolds in collagen-1. Endothelial gene expression was induced in cells cultured on scaffolds without extracellular matrix proteins. Hydroxyapatite induced gene expression for cytokeratin-19 when cells were cultured in collagen-1 gel while culture in hyaluronan increased cytokeratin-19 gene expression independent of the use of scaffold in long-term culture. The implementation of hydroxyapatite composites with extracellular matrices affected liver cell cultures and cell differentiation depending on the type of matrix protein and the presence of a scaffold. The hydroxyapatite scaffolds enable scale-up of hepatic three-dimensional culture models for regenerative medicine applications.

  7. A Novel Three-Dimensional Mouse Embryonic Implantation Model In Vitro

    Institute of Scientific and Technical Information of China (English)

    SONG Yu-xuan; CAO Bin-yun

    2007-01-01

    To regenerate three-dimensional endometrium in vitro as a novel model for studying the mechanism of implantation of embryos, the luminal epithelial cells and stromal cells of the rabbit uterus were separated and cultured in vitro. The type Ⅰ mouse tail collagen was used as scaffolding material. The stromal cells were inoculated in the type Ⅰ mouse tail collagen, and the luminal epithelial cells were inoculated on the type Ⅰ mouse tail collagen to regenerate the endometrium in vitro. The regenerated endometrium was cultured in DMEM-F/12 media containing 100 nmol L-1 progesterone, 10 nM β-estradiol, and 10% fetal bovine serum (FBS) for 3 d. The media were then replaced with CZB containing 100 nM progesterone, 10 nmol L-1 β-estradiol, and 10% FBS, and the mouse blastulas were co-cultured with it. The results of scanning electronic micrography showed that the epithelial cells on the surface of the reconstructed endometrium were covered with numerous slender microvilli and some epithelial cells protruded pinopodes. After culturing for 12 h with the mouse blastula, the shedding, attachment, and implantation of the blastula were observed. The blastula can escape from zona pellucida and attach to the three-dimensional endometrium and is then implanted into it. Thisstudy showed that the reconstructed three-dimensional endometrium can serve as a robust embryo implantation model in vitro.

  8. Modelling of Three-Dimensional Nanographene.

    Science.gov (United States)

    Mathioudakis, Christos; Kelires, Pantelis C

    2016-12-01

    Monte Carlo simulations and tight-binding calculations shed light on the properties of three-dimensional nanographene, a material composed of interlinked, covalently-bonded nanoplatelet graphene units. By constructing realistic model networks of nanographene, we study its structure, mechanical stability, and optoelectronic properties. We find that the material is nanoporous with high specific surface area, in agreement with experimental reports. Its structure is characterized by randomly oriented and curved nanoplatelet units which retain a high degree of graphene order. The material exhibits good mechanical stability with a formation energy of only ∼0.3 eV/atom compared to two-dimensional graphene. It has high electrical conductivity and optical absorption, with values approaching those of graphene. PMID:26983431

  9. Three dimensional echocardiography in congenital heart defects

    Directory of Open Access Journals (Sweden)

    Shirali Girish

    2008-01-01

    Full Text Available Three dimensional echocardiography (3DE is a new, rapidly evolving modality for cardiac imaging. Important technological advances have heralded an era where practical 3DE scanning is becoming a mainstream modality. We review the modes of 3DE that can be used. The literature has been reviewed for articles that examine the applicability of 3DE to congenital heart defects to visualize anatomy in a spectrum of defects ranging from atrioventricular septal defects to mitral valve abnormalities and Ebstein′s anomaly. The use of 3DE color flow to obtain echocardiographic angiograms is illustrated. The state of the science in quantitating right and left ventricular volumetrics is reviewed. Examples of novel applications including 3DE transesophageal echocardiography and image-guided interventions are provided. We also list the limitations of the technique, and discuss potential future developments in the field.

  10. Scaffolding for Three-Dimensional Embryonic Vasculogenesis

    Science.gov (United States)

    Kraehenbuehl, Thomas P.; Aday, Sezin; Ferreira, Lino S.

    Biomaterial scaffolds have great potential to support efficient vascular differentiation of embryonic stem cells. Vascular cell fate-specific biochemical and biophysical cues have been identified and incorporated into three-dimensional (3D) biomaterials to efficiently direct embryonic vasculogenesis. The resulting vascular-like tissue can be used for regenerative medicine applications, further elucidation of biophysical and biochemical cues governing vasculogenesis, and drug discovery. In this chapter, we give an overview on the following: (1) developmental cues for directed differentiation of human embryonic stem cells (hESCs) into vascular cells, (2) 3D vascular differentiation in embryoid bodies (EBs), (3) preparation of 3D scaffolds for the vascular differentiation of hESCs, and (4) the most significant studies combining scaffolding and hESCs for development of vascular-like tissue.

  11. Three-dimensional tori and Arnold tongues

    Science.gov (United States)

    Sekikawa, Munehisa; Inaba, Naohiko; Kamiyama, Kyohei; Aihara, Kazuyuki

    2014-03-01

    This study analyzes an Arnold resonance web, which includes complicated quasi-periodic bifurcations, by conducting a Lyapunov analysis for a coupled delayed logistic map. The map can exhibit a two-dimensional invariant torus (IT), which corresponds to a three-dimensional torus in vector fields. Numerous one-dimensional invariant closed curves (ICCs), which correspond to two-dimensional tori in vector fields, exist in a very complicated but reasonable manner inside an IT-generating region. Periodic solutions emerge at the intersections of two different thin ICC-generating regions, which we call ICC-Arnold tongues, because all three independent-frequency components of the IT become rational at the intersections. Additionally, we observe a significant bifurcation structure where conventional Arnold tongues transit to ICC-Arnold tongues through a Neimark-Sacker bifurcation in the neighborhood of a quasi-periodic Hopf bifurcation (or a quasi-periodic Neimark-Sacker bifurcation) boundary.

  12. Three-dimensional tori and Arnold tongues

    Energy Technology Data Exchange (ETDEWEB)

    Sekikawa, Munehisa, E-mail: sekikawa@cc.utsunomiya-u.ac.jp [Department of Mechanical and Intelligent Engineering, Utsunomiya University, Utsunomiya-shi 321-8585 (Japan); Inaba, Naohiko [Organization for the Strategic Coordination of Research and Intellectual Property, Meiji University, Kawasaki-shi 214-8571 (Japan); Kamiyama, Kyohei [Department of Electronics and Bioinformatics, Meiji University, Kawasaki-shi 214-8571 (Japan); Aihara, Kazuyuki [Institute of Industrial Science, the University of Tokyo, Meguro-ku 153-8505 (Japan)

    2014-03-15

    This study analyzes an Arnold resonance web, which includes complicated quasi-periodic bifurcations, by conducting a Lyapunov analysis for a coupled delayed logistic map. The map can exhibit a two-dimensional invariant torus (IT), which corresponds to a three-dimensional torus in vector fields. Numerous one-dimensional invariant closed curves (ICCs), which correspond to two-dimensional tori in vector fields, exist in a very complicated but reasonable manner inside an IT-generating region. Periodic solutions emerge at the intersections of two different thin ICC-generating regions, which we call ICC-Arnold tongues, because all three independent-frequency components of the IT become rational at the intersections. Additionally, we observe a significant bifurcation structure where conventional Arnold tongues transit to ICC-Arnold tongues through a Neimark-Sacker bifurcation in the neighborhood of a quasi-periodic Hopf bifurcation (or a quasi-periodic Neimark-Sacker bifurcation) boundary.

  13. Three-dimensional hologram display system

    Science.gov (United States)

    Mintz, Frederick (Inventor); Chao, Tien-Hsin (Inventor); Bryant, Nevin (Inventor); Tsou, Peter (Inventor)

    2009-01-01

    The present invention relates to a three-dimensional (3D) hologram display system. The 3D hologram display system includes a projector device for projecting an image upon a display medium to form a 3D hologram. The 3D hologram is formed such that a viewer can view the holographic image from multiple angles up to 360 degrees. Multiple display media are described, namely a spinning diffusive screen, a circular diffuser screen, and an aerogel. The spinning diffusive screen utilizes spatial light modulators to control the image such that the 3D image is displayed on the rotating screen in a time-multiplexing manner. The circular diffuser screen includes multiple, simultaneously-operated projectors to project the image onto the circular diffuser screen from a plurality of locations, thereby forming the 3D image. The aerogel can use the projection device described as applicable to either the spinning diffusive screen or the circular diffuser screen.

  14. Lattice Three-Dimensional Skyrmions Revisited

    CERN Document Server

    Charalampidis, E G; Kevrekidis, P G

    2014-01-01

    In the continuum a skyrmion is a topological nontrivial map between Riemannian manifolds, and a stationary point of a particular energy functional. This paper describes lattice analogues of the aforementioned skyrmions, namely a natural way of using the topological properties of the three-dimensional continuum Skyrme model to achieve topological stability on the lattice. In particular, using fixed point iterations, numerically exact lattice skyrmions are constructed; and their stability under small perturbations is verified by means of linear stability analysis. While stable branches of such solutions are identified, it is also shown that they possess a particularly delicate bifurcation structure, especially so in the vicinity of the continuum limit. The corresponding bifurcation diagram is elucidated and a prescription for selecting the branch asymptoting to the well-known continuum limit is given. Finally, the robustness of the solutions by virtue of direct numerical simulations is corroborated.

  15. Three-dimensional magnetohydrodynamic equilibria - I

    International Nuclear Information System (INIS)

    By using an analytical method, the paper treats the three-dimensional magnetohydrodynamic equilibria of an incompressible, perfectly conducting plasma with an embedded magnetic field in the presence of a gravitational field. We derive a nonlinear second-order partial differential equation for the magnetic potential or stream function. According to the basic equation obtained by us, we analyse a simple example of solutions with the realistic physical property. This set of solutions represents a magnetohydrodynamic equilibrium model for the solar prominence. The results show that the z-component of the inertia force is everywhere upward, adding to upward the Lorentz force and pressure gradient in supporting the plasma weight in a magnetic well. (author)

  16. Three-dimensional pancreas organogenesis models.

    Science.gov (United States)

    Grapin-Botton, A

    2016-09-01

    A rediscovery of three-dimensional culture has led to the development of organ biogenesis, homeostasis and disease models applicable to human tissues. The so-called organoids that have recently flourished serve as valuable models bridging between cell lines or primary cells grown on the bottom of culture plates and experiments performed in vivo. Though not recapitulating all aspects of organ physiology, the miniature organs generated in a dish are useful models emerging for the pancreas, starting from embryonic progenitors, adult cells, tumour cells and stem cells. This review focusses on the currently available systems and their relevance to the study of the pancreas, of β-cells and of several pancreatic diseases including diabetes. We discuss the expected future developments for studying human pancreas development and function, for developing diabetes models and for producing therapeutic cells. PMID:27615129

  17. Multiscale modeling of three-dimensional genome

    Science.gov (United States)

    Zhang, Bin; Wolynes, Peter

    The genome, the blueprint of life, contains nearly all the information needed to build and maintain an entire organism. A comprehensive understanding of the genome is of paramount interest to human health and will advance progress in many areas, including life sciences, medicine, and biotechnology. The overarching goal of my research is to understand the structure-dynamics-function relationships of the human genome. In this talk, I will be presenting our efforts in moving towards that goal, with a particular emphasis on studying the three-dimensional organization, the structure of the genome with multi-scale approaches. Specifically, I will discuss the reconstruction of genome structures at both interphase and metaphase by making use of data from chromosome conformation capture experiments. Computationally modeling of chromatin fiber at atomistic level from first principles will also be presented as our effort for studying the genome structure from bottom up.

  18. Towards microscale electrohydrodynamic three-dimensional printing

    Science.gov (United States)

    He, Jiankang; Xu, Fangyuan; Cao, Yi; Liu, Yaxiong; Li, Dichen

    2016-02-01

    It is challenging for the existing three-dimensional (3D) printing techniques to fabricate high-resolution 3D microstructures with low costs and high efficiency. In this work we present a solvent-based electrohydrodynamic 3D printing technique that allows fabrication of microscale structures like single walls, crossed walls, lattice and concentric circles. Process parameters were optimized to deposit tiny 3D patterns with a wall width smaller than 10 μm and a high aspect ratio of about 60. Tight bonding among neighbour layers could be achieved with a smooth lateral surface. In comparison with the existing microscale 3D printing techniques, the presented method is low-cost, highly efficient and applicable to multiple polymers. It is envisioned that this simple microscale 3D printing strategy might provide an alternative and innovative way for application in MEMS, biosensor and flexible electronics.

  19. Three-dimensional printing physiology laboratory technology.

    Science.gov (United States)

    Sulkin, Matthew S; Widder, Emily; Shao, Connie; Holzem, Katherine M; Gloschat, Christopher; Gutbrod, Sarah R; Efimov, Igor R

    2013-12-01

    Since its inception in 19th-century Germany, the physiology laboratory has been a complex and expensive research enterprise involving experts in various fields of science and engineering. Physiology research has been critically dependent on cutting-edge technological support of mechanical, electrical, optical, and more recently computer engineers. Evolution of modern experimental equipment is constrained by lack of direct communication between the physiological community and industry producing this equipment. Fortunately, recent advances in open source technologies, including three-dimensional printing, open source hardware and software, present an exciting opportunity to bring the design and development of research instrumentation to the end user, i.e., life scientists. Here we provide an overview on how to develop customized, cost-effective experimental equipment for physiology laboratories. PMID:24043254

  20. THE THREE DIMENSIONAL THERMAL HYDRAULIC CODE BAGIRA.

    Energy Technology Data Exchange (ETDEWEB)

    KALINICHENKO,S.D.; KOHUT,P.; KROSHILIN,A.E.; KROSHILIN,V.E.; SMIRNOV,A.V.

    2003-05-04

    BAGIRA - a thermal-hydraulic program complex was primarily developed for using it in nuclear power plant simulator models, but is also used as a best-estimate analytical tool for modeling two-phase mixture flows. The code models allow consideration of phase transients and the treatment of the hydrodynamic behavior of boiling and pressurized water reactor circuits. It provides the capability to explicitly model three-dimensional flow regimes in various regions of the primary and secondary circuits such as, the mixing regions, circular downcomer, pressurizer, reactor core, main primary loops, the steam generators, the separator-reheaters. In addition, it is coupled to a severe-accident module allowing the analysis of core degradation and fuel damage behavior. Section II will present the theoretical basis for development and selected results are presented in Section III. The primary use for the code complex is to realistically model reactor core behavior in power plant simulators providing enhanced training tools for plant operators.

  1. Three dimensional fabric evolution of sheared sand

    Energy Technology Data Exchange (ETDEWEB)

    Hasan, Alsidqi; Alshibli, Khalid (UWA)

    2012-10-24

    Granular particles undergo translation and rolling when they are sheared. This paper presents a three-dimensional (3D) experimental assessment of fabric evolution of sheared sand at the particle level. F-75 Ottawa sand specimen was tested under an axisymmetric triaxial loading condition. It measured 9.5 mm in diameter and 20 mm in height. The quantitative evaluation was conducted by analyzing 3D high-resolution x-ray synchrotron micro-tomography images of the specimen at eight axial strain levels. The analyses included visualization of particle translation and rotation, and quantification of fabric orientation as shearing continued. Representative individual particles were successfully tracked and visualized to assess the mode of interaction between them. This paper discusses fabric evolution and compares the evolution of particles within and outside the shear band as shearing continues. Changes in particle orientation distributions are presented using fabric histograms and fabric tensor.

  2. Towards microscale electrohydrodynamic three-dimensional printing

    International Nuclear Information System (INIS)

    It is challenging for the existing three-dimensional (3D) printing techniques to fabricate high-resolution 3D microstructures with low costs and high efficiency. In this work we present a solvent-based electrohydrodynamic 3D printing technique that allows fabrication of microscale structures like single walls, crossed walls, lattice and concentric circles. Process parameters were optimized to deposit tiny 3D patterns with a wall width smaller than 10 μm and a high aspect ratio of about 60. Tight bonding among neighbour layers could be achieved with a smooth lateral surface. In comparison with the existing microscale 3D printing techniques, the presented method is low-cost, highly efficient and applicable to multiple polymers. It is envisioned that this simple microscale 3D printing strategy might provide an alternative and innovative way for application in MEMS, biosensor and flexible electronics. (paper)

  3. Three Dimensional CAPP Technology of Projectile Based on MBD

    OpenAIRE

    Hongzhi Zhao; Yingai Piao; Xiaoyong Zhu

    2013-01-01

    This study aims at the research goal of three-dimensional digital process design of projectile, which adopts three-dimensional computer-aided process design technology based on MBD and uses MBD to conduct parametric modeling of projectile that can reduce the input of projectile’s process information and data conversion and produce reasonable, feasible and three-dimensional projectile manufacturing process to realize paperless three-dimensional process design of projectile. The application of ...

  4. Study on three dimensional seismic isolation system

    International Nuclear Information System (INIS)

    Japan Nuclear Cycle Development Institute (JNC) and Japan Atomic Power Company (JAPC) launched joint research programs on structural design and three-dimensional seismic isolation technologies, as part of the supporting R and D activities for the feasibility studies on commercialized fast breeder reactor cycle systems. A research project by JAPC under the auspices of the Ministry of Economy, Trade, and Industry (METI) with technical support by JNC is included in this joint study. This report contains the results of the research on the three-dimensional seismic isolation technologies, and the results of this year's study are summarized in the following five aspects. (1) Study on Earthquake Condition for Developing 3-dimensional Base Isolation System. The case study S2 is one of the maximum ground motions, of which the records were investigated up to this time. But a few observed near the fault exceed the case study S2 in the long period domain, depending on the fault length and conditions. Generally it is appropriate that the response spectra ratio (vertical/horizontal) is 0.6. (2) Performance Requirement for 3-dimensional Base Isolation System and Devices. Although the integrity map of main equipment/piping dominate the design criteria for the 3-dimensional base isolation system, the combined integrity map is the same as those of FY 2000, which are under fv=1Hz and over hv=20%. (3) Developing Targets and Schedule for 3-dimensional Isolation Technology. The target items for 3-dimensional base isolation system were rearranged into a table, and developing items to be examined concerning the device were also adjusted. A development plan until FY 2009 was made from the viewpoint of realization and establishment of a design guideline on 3-dimensional base isolation system. (4) Study on 3-dimensional Entire Building Base Isolation System. Three ideas among six ideas that had been proposed in FY2001, i.e., '3-dimensional base isolation system incorporating hydraulic

  5. Study on three dimensional seismic isolation system

    International Nuclear Information System (INIS)

    Japan Nuclear Cycle Development Institute (JNC) and Japan Atomic Power Company (JAPC) launched joint research programs on structural design and three-dimensional seismic isolation technologies, as part of the supporting R and D activities for the feasibility studies on commercialized fast breeder reactor cycle systems. A research project by JAPC under the auspices of the Ministry of Economy, Trade, and Industry (METI) with technical support by JNC is included in this joint study. This report contains the results of the research on the three dimensional seismic isolation technology, and the results of this study are summarized in the following five aspects. (1) Study on Requirements for the Realization of 3-dimensional Base Isolation System. The simulated seismic wave 'case study S2', which was applied to the horizontal seismic isolation study for demonstrative FBR, was adopted applying to this study. Seismic response analyses of NPP building and R/V were conducted by this wave. The conditions required for the realization of 3-dimensional isolation system for FBR were clarified in terms of vertical frequency and damping ratio of the system, considering the design criteria for the core support plate etc. and their responses in acceleration and displacement. (2) Investigation and Clarification of 3-dimensional Isolation Concepts. Three types of seismic isolation system were examined on the feature of the isolation system, development status and problems to be solved. Then, six types of seismic isolation device were also investigated on the same aspects by literature. (3) Preliminary Evaluation of 3-dimensional Isolation Concepts. By preliminarily evaluating three types of seismic isolation system on easiness, effectiveness and cost of development, 3-dimensional entire building base isolation system and horizontal entire building base isolation system with vertically isolated for main equipments were selected for FBR. Then, air and dish springs were selected as

  6. Three-dimensional imaging of lower limb neuropathies.

    Science.gov (United States)

    Ahlawat, Shivani; Carrino, John A

    2015-04-01

    Peripheral nerve pathology can be detected on high-resolution MRI on the basis of primary or secondary findings. Primary findings of nerve pathology include alterations in signal, course, and caliber; secondary findings include skeletal muscle denervation. Although two-dimensional (2D) MRI sequences comprised of a combination of fluid-sensitive and non-fat-suppressed anatomical sequences can detect changes in nerve size, signal, course, and architecture, three-dimensional (3D) imaging can play an important role in the detection and characterization of nerve pathology including caliber changes at typical compression sites, anomalous course, and nerve discontinuity. This article discusses the benefits of 3D MRI with respect to lower limb neuropathies. The article also reviews the normal anatomy of the nerves in the lower extremity from the hip joint to the foot, and it illustrates common causes and the imaging appearance of lower limb peripheral neuropathy. PMID:25764241

  7. Three-dimensional visualization of intracranial vessels and adjacent structures

    International Nuclear Information System (INIS)

    MR three-dimensional-Fourier-transform, gradient-echo sequences are available that allow the acquisition of high-quality data sets, suitable for three- dimensional image processing. Most recently, flow- compensated measurement sequences are used to achieve a three-dimensional perspective of the vascular anatomy. Spatial relationships between vessels and adjacent structures can be revealed by three-dimensional displays, showing both vessels and tissue surfaces (brain, tumor) in a three- dimensional manner. The image-processing techniques are based on the ray-tracing principle. The method can be used for the optimization of neurosurgical planning in the sellar region

  8. Three Dimensional CAPP Technology of Projectile Based on MBD

    Directory of Open Access Journals (Sweden)

    Hongzhi Zhao

    2013-07-01

    Full Text Available This study aims at the research goal of three-dimensional digital process design of projectile, which adopts three-dimensional computer-aided process design technology based on MBD and uses MBD to conduct parametric modeling of projectile that can reduce the input of projectile’s process information and data conversion and produce reasonable, feasible and three-dimensional projectile manufacturing process to realize paperless three-dimensional process design of projectile. The application of three-dimensional computer-assisted process design technology of projectile based on model definition can shorten the design cycle of projectile, thus improving rapid manufacturing capacity of product and reducing cost.

  9. THEORETICAL STUDY OF THREE-DIMENSIONAL NUMERICAL MANIFOLD METHOD

    Institute of Scientific and Technical Information of China (English)

    LUO Shao-ming; ZHANG Xiang-wei; L(U) Wen-ge; JIANG Dong-ru

    2005-01-01

    The three-dimensional numerical manifold method(NMM) is studied on the basis of two-dimensional numerical manifold method. The three-dimensional cover displacement function is studied. The mechanical analysis and Hammer integral method of three-dimensional numerical manifold method are put forward. The stiffness matrix of three-dimensional manifold element is derived and the dissection rules are given. The theoretical system and the numerical realizing method of three-dimensional numerical manifold method are systematically studied. As an example, the cantilever with load on the end is calculated, and the results show that the precision and efficiency are agreeable.

  10. Three-dimensional urban GIS for Atlanta

    Science.gov (United States)

    Bhaumik, Dharmajyoti; Faust, Nickolas L.; Estrada, Diana; Linares, Jairo

    1997-07-01

    Georgia Tech has developed a prototype system for the demonstration of the concepts of a virtual 3D geographic information system (GIS) in an urban environment. The virtual GIS integrates the technologies of GIS, remote sensing, and visualization to provide an interactive tool for the exploration of spatial data. A high density urban environment with terrain elevation, imagery, GIS layers, and three dimensional natural and manmade features is a stressing test for the integration potential of such a virtual 3D GIS. In preparation for the 1996 Olympic Games, Georgia Tech developed two highly detailed 3D databases over parts of Atlanta. A 2.5 meter database was used to depict the downtown Atlanta area with much higher resolution imagery being used for photo- texture of individual Atlanta buildings. Less than 1 meter imagery data was used to show a very accurate map of Georgia Tech, the 1996 Olympic Village. Georgia Tech developed visualization software was integrated via message passing with a traditional GIS package so that all commonly used GIS query and analysis functions could be applied within the 3D environment. This project demonstrates the versatility and productivity that can be accomplished by operating GIS functions within a virtual GIS and multi-media framework.

  11. Three-dimensional thermoluminescence spectra of feldspars

    International Nuclear Information System (INIS)

    The paper describes a systematic study of the thermoluminescence emission spectra of thirty feldspars covering the whole composition range from high potassium (orthoclase) through high sodium (albite) to high calcium (anorthite). The study was simulated by the need to understand the properties of feldspars in connection with the application of thermoluminescence to the dating of sediments. The data were obtained with a high-sensitivity Fourier transform spectrometer, which allows measurements at the low light levels found in natural samples. Three-dimensional displays in which intensity is plotted as a function of photon energy and temperature assist identification of a wide range of spectral features. A number of common features are found: an emission at 3.1 eV is strong in alkali feldspars with more than 80 mole % orthoclase and occurs with lower intensity in most other alkali feldspars and some plagioclases; a broad band with a flat maximum near 2.6 eV is found in all alkali feldspars at temperatures near 200oC when artificially irradiated, and at higher temperatures in some natural samples. Emission at 2.2 and 4.4 eV is characteristic of plagioclases with more than 75 mole % of albite. Plagioclases with more than 50 mole % anorthite, and alkali feldspars with less than 50 mole % orthoclase, emit mainly in the range 1.5-2 eV. These features can be identified with luminescence centres suggested by previous workers. The application to practical thermoluminescence dating is discussed. (Author)

  12. Automatic creation of three-dimensional avatars

    Science.gov (United States)

    Villa-Uriol, Maria-Cruz; Sainz, Miguel; Kuester, Falko; Bagherzadeh, Nader

    2003-01-01

    Highly accurate avatars of humans promise a new level of realism in engineering and entertainment applications, including areas such as computer animated movies, computer game development interactive virtual environments and tele-presence. In order to provide high-quality avatars, new techniques for the automatic acquisition and creation are required. A framework for the capture and construction of arbitrary avatars from image data is presented in this paper. Avatars are automatically reconstructed from multiple static images of a human subject by utilizing image information to reshape a synthetic three-dimensional articulated reference model. A pipeline is presented that combines a set of hardware-accelerated stages into one seamless system. Primary stages in this pipeline include pose estimation, skeleton fitting, body part segmentation, geometry construction and coloring, leading to avatars that can be animated and included into interactive environments. The presented system removes traditional constraints in the initial pose of the captured subject by using silhouette-based modification techniques in combination with a reference model. Results can be obtained in near-real time with very limited user intervention.

  13. Clinical significance of three-dimensional sonohysterography

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Eun Hye; Lee, Mi Hwa; Lee, Chan; Kim, Jong Wook; Shin, Myung Choel [Pochon Cha University College of Medicine, Pochon (Korea, Republic of)

    1999-12-15

    To evaluate the usefulness of three dimensional sonohysterography (3D SHG) in the evaluation of uterine endometrial and submucosal lesions in comparison with conventional two-dimensional sonohysterography (2D SHG). Our series consisted of 26 patients (mean aged 41 years) who complained of uterine bleeding, menorrhagia, or dysmenorrhea. 2D SHG was performed, and then 3D SHG was done after the volume mode was switched on. Simultaneous display of three perpendicular two-dimensional planes and surface rendering of findings on particular section were obtained. We analyzed whether the endometrium was thickened or not, and the location, size, shape, echogenicity, posterior shadowing, and echogenic rim of the focal lesion. The results were compared with the pathologic findings or MRI. There were submucosal myomas (n=12), intramural myomas (n=2), endometrial polyps (n=7), placental polyp (n=1), and normal endometrial cavities (n=4) on SHG. Nineteen cases were confirmed by pathologic findings or MRI. The results were correlated in 89% (17/19) of the cases. We misdiagnosed 2 cases: focal endometrial hyperplasia and choriocarcinoma were misdiagnosed as endometrial polyp and placental polyp, respectively. Imaging diagnoses were same in the techniques. Comparing with 2D SHG, 3D SHG provided a subjective display of pathologic findings and an additional information about spatial relationship between focal lesion and surroundings.

  14. Clinical significance of three-dimensional sonohysterography

    International Nuclear Information System (INIS)

    To evaluate the usefulness of three dimensional sonohysterography (3D SHG) in the evaluation of uterine endometrial and submucosal lesions in comparison with conventional two-dimensional sonohysterography (2D SHG). Our series consisted of 26 patients (mean aged 41 years) who complained of uterine bleeding, menorrhagia, or dysmenorrhea. 2D SHG was performed, and then 3D SHG was done after the volume mode was switched on. Simultaneous display of three perpendicular two-dimensional planes and surface rendering of findings on particular section were obtained. We analyzed whether the endometrium was thickened or not, and the location, size, shape, echogenicity, posterior shadowing, and echogenic rim of the focal lesion. The results were compared with the pathologic findings or MRI. There were submucosal myomas (n=12), intramural myomas (n=2), endometrial polyps (n=7), placental polyp (n=1), and normal endometrial cavities (n=4) on SHG. Nineteen cases were confirmed by pathologic findings or MRI. The results were correlated in 89% (17/19) of the cases. We misdiagnosed 2 cases: focal endometrial hyperplasia and choriocarcinoma were misdiagnosed as endometrial polyp and placental polyp, respectively. Imaging diagnoses were same in the techniques. Comparing with 2D SHG, 3D SHG provided a subjective display of pathologic findings and an additional information about spatial relationship between focal lesion and surroundings.

  15. Three-dimensional dynamics of protostellar evolution

    International Nuclear Information System (INIS)

    A three-dimensional finite difference numerical methodology was developed for self-gravitating, rotating gaseous systems. The fully nonlinear equations for time-varying fluid dynamics are solved by high speed computer in a cylindrical coordinate system rotating with an instantaneous angular velocity, selected such that the net angular momentum relative to the rotating frame is zero. The time-dependent adiabatic collapse of gravitationally bound, rotating, protostellar clouds is studied for specified uniform and nonuniform initial conditions. Uniform clouds can form axisymmetric, rotating toroidal configurations. If the thermal pressure is high, nonuniform clouds can also collapse to axisymmetric toroids. For low thermal pressures, however, the collapsing cloud is unstable to initial perturbations. The fragmentation of protostellar clouds is investigated by studying the response of rotating, self-gravitating, equilibrium toroids to non-axisymmetric perturbations. The detailed evolution of the fragmenting toroid depends upon a non-dimensional function of the initial entropy, the total mass in the toroid, the angular velocity of rotation, and the number of perturbation wavelengths around the circumference of the toroid. For low and intermediate entropies, the configuration develops into co-rotating components with spiral streamers. In the spiral regions retrograde vortices are observed in some examples. For high levels of entropy, barred spirals can exist as intermediate states of the fragmentation

  16. Three dimensional characterization and archiving system

    International Nuclear Information System (INIS)

    The Three Dimensional Characterization and Archiving System (3D-ICAS) is being developed as a remote system to perform rapid in situ analysis of hazardous organics and radionuclide contamination on structural materials. Coleman Research and its subcontractors, Thermedics Detection, Inc. (TD) and the University of Idaho (UI) are in the second phase of a three phase program to develop 3D-ICAS to support Decontamination and Decommissioning (D and D) operations. Accurate physical characterization of surfaces and the radioactive and organic is a critical D and D task. Surface characterization includes identification of potentially dangerous inorganic materials, such as asbestos and transite. Real-time remotely operable characterization instrumentation will significantly advance the analysis capabilities beyond those currently employed. Chemical analysis is a primary area where the characterization process will be improved. The 3D-ICAS system robotically conveys a multisensor probe near the surfaces to be inspected. The sensor position and orientation are monitored and controlled using coherent laser radar (CLR) tracking. The CLR also provides 3D facility maps which establish a 3D world view within which the robotic sensor system can operate

  17. Three-dimensional modeling of solidification shrinkage

    Energy Technology Data Exchange (ETDEWEB)

    Raessi, M.; Mostaghimi, J. [Univ. of Toronto, Dept. of Mechanical and Industrial Engineering, Centre for Advanced Coating Technologies, Toronto, Ontario (Canada)]. E-mail: mraessi@mie.utoronto.ca

    2003-07-01

    The three-dimensional model of droplet impact and solidification developed by M. Pasandideh-Fard et al. has been modified to include the solidification shrinkage and the associated fluid flow induced due to density difference of solid and liquid phases. A fixed-grid control volume discretization of the momentum and energy equations, combined with a volume-tracking algorithm to track the free surface has been used. The governing equations for conservation of mass, momentum and energy are derived by assuming different yet constant solid and liquid densities. The analytical solution of the Stefan problem has been used to validate the model. The model was also applied to a planar (one-dimensional) solidification of finite extent of pure tin in which the final height of completely solidified tin is known analytically. The numerical and analytical solutions were in good agreement in these two validating problems. Finally the model was used to simulate solidification shrinkage of molten tin in a cubical container. The effects of solidification shrinkage were predicted well in the free surface. (author)

  18. A three-dimensional human walking model

    Science.gov (United States)

    Yang, Q. S.; Qin, J. W.; Law, S. S.

    2015-11-01

    A three-dimensional human bipedal walking model with compliant legs is presented in this paper. The legs are modeled with time-variant dampers, and the model is able to characterize the gait pattern of an individual using a minimal set of parameters. Feedback control, for both the forward and lateral movements, is implemented to regulate the walking performance of the pedestrian. The model provides an improvement over classic invert pendulum models. Numerical studies were undertaken to investigate the effects of leg stiffness and attack angle. Simulation results show that when walking at a given speed, increasing the leg stiffness with a constant attack angle results in a longer step length, a higher step frequency, a faster walking speed and an increase in both the peak vertical and lateral ground reaction forces. Increasing the attack angle with a constant leg stiffness results in a higher step frequency, a decrease in the step length, an increase in the total energy of the system and a decrease in both the peak vertical and lateral ground reaction forces.

  19. Three-Dimensional Optical Coherence Tomography

    Science.gov (United States)

    Gutin, Mikhail; Wang, Xu-Ming; Gutin, Olga

    2009-01-01

    Three-dimensional (3D) optical coherence tomography (OCT) is an advanced method of noninvasive infrared imaging of tissues in depth. Heretofore, commercial OCT systems for 3D imaging have been designed principally for external ophthalmological examination. As explained below, such systems have been based on a one-dimensional OCT principle, and in the operation of such a system, 3D imaging is accomplished partly by means of a combination of electronic scanning along the optical (Z) axis and mechanical scanning along the two axes (X and Y) orthogonal to the optical axis. In 3D OCT, 3D imaging involves a form of electronic scanning (without mechanical scanning) along all three axes. Consequently, the need for mechanical adjustment is minimal and the mechanism used to position the OCT probe can be correspondingly more compact. A 3D OCT system also includes a probe of improved design and utilizes advanced signal- processing techniques. Improvements in performance over prior OCT systems include finer resolution, greater speed, and greater depth of field.

  20. Three-dimensionally Perforated Calcium Phosphate Ceramics

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Porous calcium phosphate ceramics were produced by compression molding using a special mold followed by sintering. The porous calcium phosphate ceramics have three-dimensional and penetrated open pores380-400μm in diameter spaced at intervals of 200μm. The layers of the linear penetration pores alternately lay perpendicular to pore direction. The porosity was 59%-65% . The Ca/P molar ratios of the porous calcium phosphate ceramics range from 1.5 to 1.85. A binder containing methyl cellulose was most effective for preparing the powder compact among vinyl acetate, polyvinyl alcohol, starch, stearic acid, methyl cellulose and their mixtures. Stainless steel, polystyrene, nylon and bamboo were used as the long columnar male dies for the penetrated open pores. When polystyrene, nylon and bamboo were used as the long columnar male dies, the dies were burned out during the sintering process. Using stainless steel as the male dies with the removal of the dies before heat treatment resulted in a higher level of densification of the calcium phosphate ceramic.

  1. Three dimensional characterization and archiving system

    Energy Technology Data Exchange (ETDEWEB)

    Sebastian, R.L.; Clark, R.; Gallman, P. [Coleman Research Corp., Springfield, VA (United States)] [and others

    1995-10-01

    The Three Dimensional Characterization and Archiving System (3D-ICAS) is being developed as a remote system to perform rapid in situ analysis of hazardous organics and radionuclide contamination on structural materials. Coleman Research and its subcontractors, Thermedics Detection, Inc. (TD) and the University of Idaho (UI) are in the second phase of a three phase program to develop 3D-ICAS to support Decontamination and Decommissioning (D&D) operations. Accurate physical characterization of surfaces and the radioactive and organic is a critical D&D task. Surface characterization includes identification of potentially dangerous inorganic materials, such as asbestos and transite. The 3D-ICAS system robotically conveys a multisensor probe near the surface to be inspected. The sensor position and orientation are monitored and controlled by Coherent laser radar (CLR) tracking. The ICAS fills the need for high speed automated organic analysis by means of gas chromatography-mass spectrometry sensors, and also by radionuclide sensors which combines alpha, beta, and gamma counting.

  2. Two and three dimensional magnetotelluric inversion

    Energy Technology Data Exchange (ETDEWEB)

    Booker, J.

    1993-01-01

    Electrical conductivity depends on properties such as the presence of ionic fluids in interconnected pores that are difficult to sense with other remote sensing techniques. Thus improved imaging of underground electrical structure has wide practical importance in exploring for groundwater, mineral and geothermal resources, and in assessing the diffusion of fluids in oil fields and waste sites. Because the electromagnetic inverse problem is fundamentally multi-dimensional, most imaging algorithms saturate available computer power long before they can deal with the complete data set. We have developed an algorithm to directly invert large multi-dimensional data sets that is orders of magnitude faster than competing methods. We have proven that a two-dimensional (2D) version of the algorithm is highly effective for real data and have made substantial progress towards a three-dimensional (3D) version. We are proposing to cure identified shortcomings and substantially expand the utility of the existing 2D program, overcome identified difficulties with extending our method to three-dimensions (3D) and embark on an investigation of related EM imaging techniques which may have the potential for even further increasing resolution.

  3. Property of three-dimensional silica composites

    Institute of Scientific and Technical Information of China (English)

    Guangyao Jia; Zhimeng Guo

    2007-01-01

    Silica fibers-reinforced,fused silica composites were fabricated with repeated vacuum-assisted liquid-phase infiltration.The mechanical properties,thermal properties,and ablative properties of the samples were evaluated.The effect of the silica fiber content and treatment temperature on the flexural strength of the three-dimensional SiO2 (3-D SiO2) composites also was investigated.The SiO2composites show good mechanical properties and excellent ablative performance.The flexural strength increases with an increase in silica fiber content,and decreases with an increase in treatment temperature.When the volume fraction of the silica fiber is 50vo1% and the treatment temperature is 700 ℃,the flexural strength of the composites reaches a maximum value of 78 MPa.By adding cyclohexanone surfactant,the infiltration property can be largely improved,resulting in the density of SiO2 composites increasing up to 1.65g/cm3.The fracture surfaces of the flexural specimens observed using SEM,show that the pseudoplasticity and the toughening mechanisms of the composites are caused by absorption of a lot of energy by interface debonding and fiber pulling out.

  4. Three Dimensional Numerical Analysis on Discharge Properties

    Science.gov (United States)

    Takaishi, Kenji; Katsurai, Makoto

    2003-10-01

    A three dimensional simulation code with the finite difference time domain (FDTD) method combined with the two fluids model for electron and ion has been developed for the microwave excited surface wave plasma in the RDL-SWP device. This code permits the numerical analysis of the spatial distributions of electric field, power absorption, electron density and electron temperature. At low gas pressure of about 10 mTorr, the numerical results compared with the experimental measurements that shows the validity of this 3-D simulation code. A simplified analysis assuming that an electron density is spatially uniform has been studied and its applicability is evaluated by 3-D simulation. The surface wave eigenmodes are determined by electron density, and it is found that the structure of the device strongly influences to the spatial distribution of the electric fields of surface wave in a low density area. A method to irradiate a microwave to the whole surface area of the plasma is proposed which is found to be effective to obtain a high uniformity distribution of electron density.

  5. Three-dimensional Printing in the Intestine.

    Science.gov (United States)

    Wengerter, Brian C; Emre, Gulus; Park, Jea Young; Geibel, John

    2016-08-01

    Intestinal transplantation remains a life-saving option for patients with severe intestinal failure. With the advent of advanced tissue engineering techniques, great strides have been made toward manufacturing replacement tissues and organs, including the intestine, which aim to avoid transplant-related complications. The current paradigm is to seed a biocompatible support material (scaffold) with a desired cell population to generate viable replacement tissue. Although this technique has now been extended by the three-dimensional (3D) printing of geometrically complex scaffolds, the overall approach is hindered by relatively slow turnover and negative effects of residual scaffold material, which affects final clinical outcome. Methods recently developed for scaffold-free 3D bioprinting may overcome such obstacles and should allow for rapid manufacture and deployment of "bioprinted organs." Much work remains before 3D bioprinted tissues can enter clinical use. In this brief review we examine the present state and future perspectives of this nascent technology before full clinical implementation. PMID:27189913

  6. PLOT3D- DRAWING THREE DIMENSIONAL SURFACES

    Science.gov (United States)

    Canright, R. B.

    1994-01-01

    PLOT3D is a package of programs to draw three-dimensional surfaces of the form z = f(x,y). The function f and the boundary values for x and y are the input to PLOT3D. The surface thus defined may be drawn after arbitrary rotations. However, it is designed to draw only functions in rectangular coordinates expressed explicitly in the above form. It cannot, for example, draw a sphere. Output is by off-line incremental plotter or online microfilm recorder. This package, unlike other packages, will plot any function of the form z = f(x,y) and portrays continuous and bounded functions of two independent variables. With curve fitting; however, it can draw experimental data and pictures which cannot be expressed in the above form. The method used is division into a uniform rectangular grid of the given x and y ranges. The values of the supplied function at the grid points (x, y) are calculated and stored; this defines the surface. The surface is portrayed by connecting successive (y,z) points with straight-line segments for each x value on the grid and, in turn, connecting successive (x,z) points for each fixed y value on the grid. These lines are then projected by parallel projection onto the fixed yz-plane for plotting. This program has been implemented on the IBM 360/67 with on-line CDC microfilm recorder.

  7. Why Observable Space Is Solely Three Dimensional

    CERN Document Server

    Rabinowitz, Mario

    2015-01-01

    Quantum (and classical) binding energy considerations in n-dimensional space indicate that atoms (and planets) can only exist in three-dimensional space. This is why observable space is solely 3-dimensional. Both a novel Virial theorem analysis, and detailed classical and quantum energy calculations for 3-space circular and elliptical orbits indicate that they have no orbital binding energy in greater than 3-space. The same energy equation also excludes the possibility of atom-like bodies in strictly 1 and 2-dimensions. A prediction is made that in the search for deviations from r^-2 of the gravitational force at sub-millimeter distances such a deviation must occur at < ~ 10^-10 m (or < ~10^-12 m considering muoniom), since atoms would disintegrate if the curled up dimensions of string theory were larger than this. Callender asserts that the often-repeated claim in previous work that stable orbits are possible in only three dimensions is not even remotely established. The binding energy analysis herein ...

  8. Chaotic Mixing in Three Dimensional Porous Media

    CERN Document Server

    Lester, Daniel R; Borgne, Tanguy Le

    2016-01-01

    Under steady flow conditions, the topological complexity inherent to all random 3D porous media imparts complicated flow and transport dynamics. It has been established that this complexity generates persistent chaotic advection via a three-dimensional (3D) fluid mechanical analogue of the baker's map which rapidly accelerates scalar mixing in the presence of molecular di?usion. Hence pore-scale fluid mixing is governed by the interplay between chaotic advection, molecular di?usion and the broad (power-law) distribution of fluid particle travel times which arise from the non-slip condition at pore walls. To understand and quantify mixing in 3D porous media, we consider these processes in a model 3D open porous network and develop a novel stretching continuous time random walk (CTRW) which provides analytic estimates of pore-scale mixing which compare well with direct numerical simulations. We ?nd that chaotic advection inherent to 3D porous media imparts scalar mixing which scales exponentially with longitudi...

  9. Three dimensional characterization and archiving system

    Energy Technology Data Exchange (ETDEWEB)

    Sebastian, R.L.; Clark, R.; Gallman, P. [and others

    1995-12-01

    The Three Dimensional Characterization and Archiving System (3D-ICAS) is being developed as a remote system to perform rapid in situ analysis of hazardous organics and radionuclide contamination on structural materials. Coleman Research and its subcontractors, Thermedics Detection, Inc. (TD) and the University of Idaho (UI) are in the second phase of a three phase program to develop 3D-ICAS to support Decontamination and Decommissioning (D&D) operations. Accurate physical characterization of surfaces and the radioactive and organic is a critical D&D task. Surface characterization includes identification of potentially dangerous inorganic materials, such as asbestos and transite. Real-time remotely operable characterization instrumentation will significantly advance the analysis capabilities beyond those currently employed. Chemical analysis is a primary area where the characterization process will be improved. Chemical analysis plays a vital role throughout the process of decontamination. Before clean-up operations can begin the site must be characterized with respect to the type and concentration of contaminants, and detailed site mapping must clarify areas of both high and low risk. During remediation activities chemical analysis provides a means to measure progress and to adjust clean-up strategy. Once the clean-up process has been completed the results of chemical analysis will verify that the site is in compliance with federal and local regulations.

  10. Three dimensional characterization and archiving system

    International Nuclear Information System (INIS)

    The Three Dimensional Characterization and Archiving System (3D-ICAS) is being developed as a remote system to perform rapid in situ analysis of hazardous organics and radionuclide contamination on structural materials. Coleman Research and its subcontractors, Thermedics Detection, Inc. (TD) and the University of Idaho (UI) are in the second phase of a three phase program to develop 3D-ICAS to support Decontamination and Decommissioning (D ampersand D) operations. Accurate physical characterization of surfaces and the radioactive and organic is a critical D ampersand D task. Surface characterization includes identification of potentially dangerous inorganic materials, such as asbestos and transite. Real-time remotely operable characterization instrumentation will significantly advance the analysis capabilities beyond those currently employed. Chemical analysis is a primary area where the characterization process will be improved. Chemical analysis plays a vital role throughout the process of decontamination. Before clean-up operations can begin the site must be characterized with respect to the type and concentration of contaminants, and detailed site mapping must clarify areas of both high and low risk. During remediation activities chemical analysis provides a means to measure progress and to adjust clean-up strategy. Once the clean-up process has been completed the results of chemical analysis will verify that the site is in compliance with federal and local regulations

  11. Three-dimensional RAMA fluence methodology benchmarking

    International Nuclear Information System (INIS)

    This paper describes the benchmarking of the RAMA Fluence Methodology software, that has been performed in accordance with U. S. Nuclear Regulatory Commission Regulatory Guide 1.190. The RAMA Fluence Methodology has been developed by TransWare Enterprises Inc. through funding provided by the Electric Power Research Inst., Inc. (EPRI) and the Boiling Water Reactor Vessel and Internals Project (BWRVIP). The purpose of the software is to provide an accurate method for calculating neutron fluence in BWR pressure vessels and internal components. The Methodology incorporates a three-dimensional deterministic transport solution with flexible arbitrary geometry representation of reactor system components, previously available only with Monte Carlo solution techniques. Benchmarking was performed on measurements obtained from three standard benchmark problems which include the Pool Criticality Assembly (PCA), VENUS-3, and H. B. Robinson Unit 2 benchmarks, and on flux wire measurements obtained from two BWR nuclear plants. The calculated to measured (C/M) ratios range from 0.93 to 1.04 demonstrating the accuracy of the RAMA Fluence Methodology in predicting neutron flux, fluence, and dosimetry activation. (authors)

  12. MORPHOLOGICAL DESCRIPTIONS USING THREE-DIMENSIONAL WAVEFRONTS

    Directory of Open Access Journals (Sweden)

    Jean Serra

    2011-05-01

    Full Text Available The present study deals with the analysis of three-dimensional binary objects whose structure is not obvious nor generally clearly visible. Our approach is illustrated through three examples taken from biological microscopy. In one of our examples, we need to extract the osteocytes contained in sixty confocal sections. The cells are not numerous, but are characterized by long branches, hence they will be separated using a directional wavefront The two other objects are more complex and will be analysed by means of a spherical wavefront In the first case, a kidney of a rat embryo, the tissue grows like a tree, where we want to detect the branches, their extremities,and their spatial arrangement. The wavefront method enables us to define precisely branches and extremities, and gives flexible algorithms. The last example deals with the embryonic growth of the chicken shinbone. The central part of the bone (or shaft is structured as a series of nested cylinders following the same axis, and connected by more or less long bridges. Using wavefronts, we show that it is possible to separate the cylinders,and to extract and count the bridges that connect them.

  13. Application of Simulated Three Dimensional CT Image in Orthognathic Surgery

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyun Don; Park, Chang Seo [Dept. of Dental Radiology, College of Dentistry, Yensei University, Seoul (Korea, Republic of); Yoo, Sun Kook; Lee, Kyoung Sang [Dept. of Medical Engineering, College of Medicine, Yensei University, Seoul (Korea, Republic of)

    1998-08-15

    In orthodontics and orthognathic surgery, cephalogram has been routine practice in diagnosis and treatment evaluation of craniofacial deformity. But its inherent distortion of actual length and angles during projecting three dimensional object to two dimensional plane might cause errors in quantitative analysis of shape and size. Therefore, it is desirable that three dimensional object is diagnosed and evaluated three dimensionally and three dimensional CT image is best for three dimensional analysis. Development of clinic necessitates evaluation of result of treatment and comparison before and after surgery. It is desirable that patient that was diagnosed and planned by three dimensional computed tomography before surgery is evaluated by three dimensional computed tomography after surgery, too. But Because there is no standardized normal values in three dimension now and three dimensional Computed Tomography needs expensive equipment and because of its expenses and amount of exposure to radiation, limitations still remain to be solved in its application to routine practice. If postoperative three dimensional image is constructed by pre and postoperative lateral and postero-anterior cephalograms and preoperative three dimensional computed tomogram, pre and postoperative image will be compared and evaluated three dimensionally without three dimensional computed tomography after surgery and that will contribute to standardize normal values in three dimension. This study introduced new method that computer-simulated three dimensional image was constructed by preoperative three dimensional computed tomogram and pre and postoperative lateral and postero-anterior cephalograms, and for validation of new method, in four cases of dry skull that position of mandible was displaced and four patients of orthognathic surgery, computer-simulated three dimensional image and actual postoperative three dimensional image were compared. The results were as follows. 1. In four cases of

  14. Panoramic three-dimensional CT imaging

    International Nuclear Information System (INIS)

    Panoramic radiography is a unique projection technique for producing a single image of both maxillary and mandibular arches and many other anatomical structures. To obtain a similar panoramic image without panoramic radiography system, a modified three-dimensional (3D) CT imaging technique was designed. A set of CT slice image data extending from the chin to the orbit was used for 3D reconstruction. The CT machine used in this study was the X-Vision (TOSHIBA, Japan). The helical scan technique was used. The slice thickness of reconstructed image was one or 1.5 mm. The occlusal plane or Frankfort horizontal (FH) plane was used as the reference line. The resultant slice image data was stored on a magnetic optical disk and then used to create panoramic 3D-CT images on a Macintosh computer systems (Power Macintosh 8600/250, Apple Computer Inc., USA). To create the panoramic 3D-CT image, the following procedure was designed: Design a curved panoramic 3D-CT imaging layer using the imaging layer and the movement of the x-ray beam in panoramic radiography system as a template; Cut this imaging layer from each slice image, then the trimmed image was transformed to a rectangular layer using the ''still image warping'' special effect in the Elastic Reality special effects system (Elastic Reality Inc., USA); Create panoramic 3D-CT image using the Voxel View (Vital Images Inc., USA) rendering system and volume rendering technique. Although the image quality was primitive, a panoramic view of maxillofacial region was obtained by this technique. (author)

  15. Panoramic three-dimensional CT imaging

    Energy Technology Data Exchange (ETDEWEB)

    Kawamata, Akitoshi; Fujishita, Masami [Asahi Univ., Hozumi, Gifu (Japan). School of Dentistry

    1998-09-01

    Panoramic radiography is a unique projection technique for producing a single image of both maxillary and mandibular arches and many other anatomical structures. To obtain a similar panoramic image without panoramic radiography system, a modified three-dimensional (3D) CT imaging technique was designed. A set of CT slice image data extending from the chin to the orbit was used for 3D reconstruction. The CT machine used in this study was the X-Vision (TOSHIBA, Japan). The helical scan technique was used. The slice thickness of reconstructed image was one or 1.5 mm. The occlusal plane or Frankfort horizontal (FH) plane was used as the reference line. The resultant slice image data was stored on a magnetic optical disk and then used to create panoramic 3D-CT images on a Macintosh computer systems (Power Macintosh 8600/250, Apple Computer Inc., USA). To create the panoramic 3D-CT image, the following procedure was designed: Design a curved panoramic 3D-CT imaging layer using the imaging layer and the movement of the x-ray beam in panoramic radiography system as a template; Cut this imaging layer from each slice image, then the trimmed image was transformed to a rectangular layer using the ``still image warping`` special effect in the Elastic Reality special effects system (Elastic Reality Inc., USA); Create panoramic 3D-CT image using the Voxel View (Vital Images Inc., USA) rendering system and volume rendering technique. Although the image quality was primitive, a panoramic view of maxillofacial region was obtained by this technique. (author)

  16. CYLSEC: A three dimensional shield evaluation code

    International Nuclear Information System (INIS)

    Existing point kernel gamma codes are either limited to simple geometry configurations or require rather cumbersome input. These codes also require the user to specify the mesh size used in integrating the kernel. This results in computational inefficiencies since it is difficult to establish criteria for choosing mesh size and because it is generally not possible to assure convergence without solving the problem more than once. The interactive program CYLSEC was recently developed to improve this situation. CYLSEC can be used to evaluate bulk or local shielding for radioactive components, to treat streaming problems and to calculate a variety of gamma ray response functions. It will accept three dimensional geometries that can be described in terms of orthogonal slabs, right cylinders and/or right parallelepipeds. While the problem geometry is specified in rectangular coordinates, the integration of the kernel is performed in spherical coordinates. This allows explicit integration over the radial variable, thus reducing the problem to a double integral. The integral mesh size varies and is internally determined such that a specified convergence criterion is met. CYLSEC is also designed to recognize and take advantage of any problem symmetry in order to maximize efficiency. Program input is through interactive routines that are self checking and permit the user to make corrections. A gamma ray data library is provided, however, alternate data may be specified if desired. Comparisons between CYLSEC and other point kernel codes (QAD, GRACE) show excellent agreement in results and demonstrate that CYLSEC requires significantly less CPU time. Comparisons with the discrete ordinates code ANISN also show good agreement. An additional attraction to CYLSEC is that it is suitable for conversion to mini or personal computers

  17. Measurements using three-dimensional product imaging

    Directory of Open Access Journals (Sweden)

    A. Sioma

    2010-07-01

    Full Text Available This article discusses a method of creating a three-dimensional cast model using vision systems and how that model can be used in thequality assessment process carried out directly on the assembly line. The technology of active vision, consisting in illumination of theobject with a laser beam, was used to create the model. Appropriate configuration of camera position geometry and laser light allows thecollection of height profiles and construction of a 3D model of the product on their basis. The article discusses problems connected with the resolution of the vision system, resolution of the laser beam analysis, and resolution connected with the application of the successive height profiles on sample cast planes. On the basis of the model, measurements allowing assessment of dimension parameters and surface defects of a given cast are presented. On the basis of tests and analyses of such a threedimensional cast model, a range of checks which are possible to conduct using 3D vision systems is indicated.Testing casts using that technology allows rapid assessment of selected parameters. Construction of the product’s model and dimensional assessment take a few seconds, which significantly reduces the duration of checks in the technological process. Depending on the product, a few checks may be carried out simultaneously on the product’s model.The possibility of controlling all outgoing products, and creating and modifying the product parameter control program, makes the solutionhighly flexible, which is confirmed by pilot industrial implementations. The technology will be developed in terms of detection andidentification of surface defects. It is important due to the possibility of using such information for the purposes of selecting technologicalprocess parameters and observing the effect of changes in selected parameters on the cast parameter controlled in a vision system.

  18. Electromagnetic scattering from three dimensional periodic structures

    Science.gov (United States)

    Barnes, Andrew L.

    We have developed a numerical method for solving electromagnetic scattering problems from arbitrary, smooth, three dimensional structures that are periodic in two directions and of finite thickness in the third direction. We solve Maxwell's equations via an integral equation that was first formulated by Claus Muller. The Muller integral equation is Fredholm of the second kind, so it is a well-posed problem. The original Muller formulation was for compact scatterers and it used a free space Green's function for the Helmholtz equation. We solve a periodic problem with a periodic Helmholtz Green's function. This Green's function has the same degree of singularity as the free space Helmholtz Green's function, but it is an infinite sum that converges very slowly. We use a resummation technique (due to P. P. Ewald) to perform an efficient calculation of the periodic Green's function. We solve the integral equation by a Galerkin method and use RWG vector basis functions to discretize surface currents on the scatterer. We perform a careful extraction of all singularities from the integrals that we compute. We use a triangular Gaussian quadrature method for calculation of the non-singular parts of the integrals. We analytically compute the remaining singular and nearly singular integrals. We also perform an acceleration technique that treats several frequencies simultaneously and leads to decreased computational times. In addition to the numerical code, we present an alternative way of looking at electromagnetic scattering in terms of Calderon projection operators. We have validated our computer code by comparing the numerical results with results from two separate cases. The first case is that of a flat dielectric slab of finite thickness, for which exact formulae are available. The second case is a periodic array of a row of infinite cylinders. In this case, we compare our results with those obtainedv from a two dimensional code developed by S. P. Shipman, S. Venakides

  19. Airway branching morphogenesis in three dimensional culture

    Directory of Open Access Journals (Sweden)

    Gudjonsson Thorarinn

    2010-11-01

    Full Text Available Abstract Background Lungs develop from the fetal digestive tract where epithelium invades the vascular rich stroma in a process called branching morphogenesis. In organogenesis, endothelial cells have been shown to be important for morphogenesis and the maintenance of organ structure. The aim of this study was to recapitulate human lung morphogenesis in vitro by establishing a three dimensional (3D co-culture model where lung epithelial cells were cultured in endothelial-rich stroma. Methods We used a human bronchial epithelial cell line (VA10 recently developed in our laboratory. This cell line cell line maintains a predominant basal cell phenotype, expressing p63 and other basal markers such as cytokeratin-5 and -14. Here, we cultured VA10 with human umbilical vein endothelial cells (HUVECs, to mimic the close interaction between these cell types during lung development. Morphogenesis and differentiation was monitored by phase contrast microscopy, immunostainings and confocal imaging. Results We found that in co-culture with endothelial cells, the VA10 cells generated bronchioalveolar like structures, suggesting that lung epithelial branching is facilitated by the presence of endothelial cells. The VA10 derived epithelial structures display various complex patterns of branching and show partial alveolar type-II differentiation with pro-Surfactant-C expression. The epithelial origin of the branching VA10 colonies was confirmed by immunostaining. These bronchioalveolar-like structures were polarized with respect to integrin expression at the cell-matrix interface. The endothelial-induced branching was mediated by soluble factors. Furthermore, fibroblast growth factor receptor-2 (FGFR-2 and sprouty-2 were expressed at the growing tips of the branching structures and the branching was inhibited by the FGFR-small molecule inhibitor SU5402. Discussion In this study we show that a human lung epithelial cell line can be induced by endothelial cells to

  20. Three-Dimensional Mapping of Hippocampal Anatomy in Adolescents with Bipolar Disorder

    Science.gov (United States)

    Bearden, Carrie E.; Soares, Jair C.; Klunder, Andrea D.; Nicoletti, Mark; Dierschki, Nicole; Hayashi, Kiralee M.; Narr, Katherine L.; Bhrambilla, Paolo; Sassi, Roberto B.; Axelson, David; Ryan, Neal; Birmaher, Boris; Thompson, Paul M.

    2008-01-01

    The article discusses the use of three-dimensional mapping methods in children and adolescents with bipolar disorder to find out if localized alterations in hippocampal structure are exhibited. It also explores the developmental differences where the patient with bipolar disorder showed increasing hippocampal size with increasing age.

  1. Virtual Audio - Three-Dimensional Audio in Virtual Environments

    OpenAIRE

    Adler, Daniel

    1996-01-01

    Three-dimensional interactive audio has a variety ofpotential uses in human-machine interfaces. After lagging seriously behind the visual components, the importance of sound is now becoming increas-ingly accepted. This paper mainly discusses background and techniques to implement three-dimensional audio in computer interfaces. A case study of a system for three-dimensional audio, implemented by the author, is described in great detail. The audio system was moreover integra...

  2. A physiologic three-dimensional cell culture system to investigate the role of decorin in matrix organisation and cell survival

    International Nuclear Information System (INIS)

    In vivo cells exist in a three-dimensional environment generated and maintained by multiple cell-cell and cell-matrix interactions. Proteoglycans, like decorin, affect these complex interactions. Thus, we sought to investigate the role of decorin in a three-dimensional environment where the matrix was generated over time by decorin-deficient fibroblasts in the presence of L-ascorbic acid 2-phosphate. The cells were viable and proliferated in response to FGF2. Decorin was incorporated in the matrix and caused a ∼2 nm shift in the average diameter of the collagen fibrils, and the range and distribution of the fibrils became narrower and more uniform. Although there were no appreciable changes in collagen composition, we found that exogenous decorin induced the de novo synthesis of collagen I and V and cross-linked β (I). In the early phases of the three-dimensional culture, decorin reduced apoptosis. However, following the establishment of a three-dimensional matrix, the cells did not require decorin for their survival

  3. Alterations in biosynthetic accumulation of collagen types I and III during growth and morphogenesis of embryonic mouse salivary glands

    Science.gov (United States)

    Hardman, P.; Spooner, B. S.

    1992-01-01

    We examined the biosynthetic patterns of interstitial collagens in mouse embryonic submandibular and sublingual glands cultured in vitro. Rudiments explanted on day 13 of gestation and cultured for 24, 48, and 72 h all synthesized collagen types I, III, and V. However, while the total incorporation of label into collagenous proteins did not change over the three-day culture period, the rate of accumulation of newly synthesized types I and III did change. At 24 h, the ratio of newly synthesized collagen types I:III was approximately 2, whereas at 72 h, the ratio was approximately 5. These data suggest that collagen types I and III may be important in initiation of branching in this organ, but that type I may become dominant in the later stages of development and in maintenance of the adult organ.

  4. Three-dimensional X-ray micro-velocimetry

    International Nuclear Information System (INIS)

    Three-dimensional X-ray velocimetry with micrometer-level resolution is demonstrated. A direct measurement of three-dimensional X-ray velocimetry with micrometer spatial resolution is presented. The key to this development is the use of a Laue crystal as an X-ray beam splitter and mirror. Three-dimensional flow velocities in a 0.4 mm-diameter tubing were recorded, with <5 µm spatial resolution and speeds of 0.7 mm s−1. This development paves the way for three-dimensional velocimetry in many cases where visible-light techniques are not effective, such as multiphase flow or flow of optically opaque liquids

  5. Cytoskeletal organization and collagen orientation in the fish scales.

    Science.gov (United States)

    Zylberberg, L; Bereiter-Hahn, J; Sire, J Y

    1988-09-01

    Immunofluorescence and electron microscopy were used to analyze the relationships between the organization of collagen fibrils in elasmoid scales, and the orientation of microtubules and actin microfilaments in the scleroblasts producing this collagenous stroma. Attention was focused on the basal plate of the scales because of the highly ordered three-dimensional arrangement of the collagen fibrils in superimposed plies forming an acellular plywood-like structure. The collagen fibrils are synthesized by the scleroblasts forming a monolayered pseudo-epithelium, the hyposquama, at the lowest surface of the scale. Fully developed scales with a low collagen deposition rate were compared with regenerating scales active in fibrillogenesis. When an ordered array of the collagen fibrils is found, the innermost collagen fibrils are coaligned with microtubules and actin microfilaments. Thus, because of this coalignment, microtubules and actin microfilaments of the hyposquamal scleroblasts are subjected to consecutive alterations during the formation of the plies of the basal plate. The sequence of events when the collagen fibrils change their direction from one ply to the other in the basal plate is deduced from immunofluorescence and phase-contrast-microscopic observations. During the formation of the orthogonal plywood-like structure in the regenerating scales, first microtubules may change their curse with a rotating angle of about 90 degrees; then, actin microfilaments are disorganized and reorganized by interacting mechanically with the microtubules with which they are coaligned. Collagen fibrils are synthesized in a direction that is roughly perpendicular to that of the preceding ply. The unknown signals inducing the change in direction of the cytoskeleton may be transmitted throughout the hyposquama via gap junctions. PMID:3052849

  6. Three-dimensional context regulation of metastasis

    DEFF Research Database (Denmark)

    Erler, Janine Terra; Weaver, Valerie M

    2009-01-01

    stroma to promote transformation, tumor growth, motility and invasion, enhance cancer cell survival, enable metastatic dissemination, and facilitate the establishment of tumor cells at distant sites. Matrix degradation can additionally promote malignant progression and metastasis. Tumor hypoxia...... is functionally linked to altered stromal-epithelial interactions. Hypoxia additionally induces the expression of pro-migratory, survival and invasion genes, and up-regulates expression of ECM components and modifying enzymes, to enhance tumor progression and metastasis. Synergistic interactions between matrix...

  7. Advanced Three-Dimensional Display System

    Science.gov (United States)

    Geng, Jason

    2005-01-01

    A desktop-scale, computer-controlled display system, initially developed for NASA and now known as the VolumeViewer(TradeMark), generates three-dimensional (3D) images of 3D objects in a display volume. This system differs fundamentally from stereoscopic and holographic display systems: The images generated by this system are truly 3D in that they can be viewed from almost any angle, without the aid of special eyeglasses. It is possible to walk around the system while gazing at its display volume to see a displayed object from a changing perspective, and multiple observers standing at different positions around the display can view the object simultaneously from their individual perspectives, as though the displayed object were a real 3D object. At the time of writing this article, only partial information on the design and principle of operation of the system was available. It is known that the system includes a high-speed, silicon-backplane, ferroelectric-liquid-crystal spatial light modulator (SLM), multiple high-power lasers for projecting images in multiple colors, a rotating helix that serves as a moving screen for displaying voxels [volume cells or volume elements, in analogy to pixels (picture cells or picture elements) in two-dimensional (2D) images], and a host computer. The rotating helix and its motor drive are the only moving parts. Under control by the host computer, a stream of 2D image patterns is generated on the SLM and projected through optics onto the surface of the rotating helix. The system utilizes a parallel pixel/voxel-addressing scheme: All the pixels of the 2D pattern on the SLM are addressed simultaneously by laser beams. This parallel addressing scheme overcomes the difficulty of achieving both high resolution and a high frame rate in a raster scanning or serial addressing scheme. It has been reported that the structure of the system is simple and easy to build, that the optical design and alignment are not difficult, and that the

  8. [The potential of three-dimensional tumor models and cell culturing in cancer research and diagnostics].

    Science.gov (United States)

    Alföldi, Róbert; Szebeni, János Gábor; Puskás, G László

    2015-12-01

    In vitro testing of antitumor agents on human cancer cell lines has become essential in pharmaceutical research and in clinical practice. Although the most widely used technique is the two-dimensional cell growing protocol (in tissue culture plates), the new three-dimensional methods are becoming more and more popular as their structure and complexity is more similar to the microenvironment of the real tumor. The aim of the present study is to describe the most widely used in vitro three-dimensional tumor models and to compare a RAFT(TM) three dimensional in vitro tumor model with the traditional two-dimensional tumor cell cultures. In the study, the viability and the enzyme activity of cultured A549 non-small cell lung cancer (NSCLC) cells under different conditions were compared. The results show that while the number of necrotic cells increased significantly (20-fold; 2D/A549 T75 conventional tissue culture flask 1.6%; 2D/A549-collagen coated T75 tissue culture flask 1.45%, RAFT(TM) 22.11%) during long culturing period in the RAFT(TM) three-dimensional in vitro tumor model, there was no significant difference during the conventional antitumor screening period (3-5 day) compared to the traditional two-dimensional cell cultures. The structure of the tumor cell islets grown with RAFT(TM) is much more complex than that of the traditional two-dimensional cultures. Thus, similarly to the in vivo tumor microenvironment, there is also a collagen matrix in the extracellular space which can have significant effect on the diffusion of the antitumor agents to cells. In conclusion, it can be stated that testing of antitumor agents on tumor cells cultured in three-dimensional systems can be an important complementary method to the traditional two-dimensional in vitro analyses. The results of the new three-dimensional method can be more easily applied in the in vivo analysis and translated into clinical practice. PMID:26665190

  9. Layer by Layer Three-dimensional Tissue Epitaxy by Cell-Laden Hydrogel Droplets

    OpenAIRE

    Moon, SangJun; Hasan, Syed K.; Song, Young S.; Xu, Feng; Keles, Hasan Onur; Manzur, Fahim; Mikkilineni, Sohan; Hong, Jong Wook; Nagatomi, Jiro; Haeggstrom, Edward; Khademhosseini, Ali; Demirci, Utkan

    2009-01-01

    The ability to bioengineer three-dimensional (3D) tissues is a potentially powerful approach to treat diverse diseases such as cancer, loss of tissue function, or organ failure. Traditional tissue engineering methods, however, face challenges in fabricating 3D tissue constructs that resemble the native tissue microvasculature and microarchitectures. We have developed a bioprinter that can be used to print 3D patches of smooth muscle cells (5 mm × 5 mm × 81 μm) encapsulated within collagen. Cu...

  10. Pathogen propagation in cultured three-dimensional tissue mass

    Science.gov (United States)

    Goodwin, Thomas J. (Inventor); Spaulding, Glenn F. (Inventor); Wolf, David A. (Inventor)

    2000-01-01

    A process for propagating a pathogen in a three-dimensional tissue mass cultured at microgravity conditions in a culture vessel containing culture media and a culture matrix is provided. The three-dimensional tissue mass is inoculated with a pathogen and pathogen replication in the cells of the tissue mass achieved.

  11. Semifolded Localized Structures in Three-Dimensional Soliton Systems

    Institute of Scientific and Technical Information of China (English)

    FANG Jian-Ping; ZHENG Chun-Long; CHEN Li-Qun

    2004-01-01

    By means ora Painlevé-Backlund transformation and a multi-linear variable separation approach, abundant localized coherent excitations of the three-dimensional Broer-Kaup-Kupershmidt system with variable coefficients are derived. There are possible phase shifts for the interactions of the three-dimensional novel localized structures discussed in this paper.

  12. Classification of two and three dimensional Lie super-bialgebras

    CERN Document Server

    Eghbali, A; Rezaei-Aghdam, A

    2009-01-01

    Using adjoint representation of Lie superalgebras, we write the matrix form of super Jacobi and mixed super Jacobi identities of Lie super-bialgebras. Then through direct calculations of these identities and use of automorphism supergroups of two and three dimensional Lie superalgebras, we obtain and classify all two and three dimensional Lie super-bialgebras.

  13. Single shot three-dimensional imaging of dilute atomic clouds

    CERN Document Server

    Sakmann, Kaspar

    2014-01-01

    Light field microscopy methods together with three dimensional (3D) deconvolution can be used to obtain single shot 3D images of atomic clouds. We demonstrate the method using a test setup which extracts three dimensional images from a fluorescent $^{87}$Rb atomic vapor.

  14. Collapse in a forced three-dimensional nonlinear Schrodinger equation

    DEFF Research Database (Denmark)

    Lushnikov, P.M.; Saffman, M.

    2000-01-01

    We derive sufficient conditions for the occurrence of collapse in a forced three-dimensional nonlinear Schrodinger equation without dissipation. Numerical studies continue the results to the case of finite dissipation.......We derive sufficient conditions for the occurrence of collapse in a forced three-dimensional nonlinear Schrodinger equation without dissipation. Numerical studies continue the results to the case of finite dissipation....

  15. Statistical Entropy of Three-Dimensional Spherical Spacetime

    Institute of Scientific and Technical Information of China (English)

    WANG Bin; SU Ru-Keng; FENG Shi-Xiang

    2000-01-01

    By means of conformal field theory, we have related the degrees of freedom of microstates to the entropy of three dimensional charged black hole as well as the entanglement entropy of three-dimensional De Sitter spacetime.We have shown that the degrees of freedom of the conformal theory responsible for the entropy represent states on the horizon and localized in physical spacetime.

  16. Three-dimensional X-ray micro-velocimetry

    OpenAIRE

    Lee, Wah-Keat; Fezzaa, Kamel; Uemura, Tomomasa

    2010-01-01

    A direct measurement of three-dimensional X-ray velocimetry with micrometer spatial resolution is presented. The key to this development is the use of a Laue crystal as an X-ray beam splitter and mirror. Three-dimensional flow velocities in a 0.4 mm-diameter tubing were recorded, with

  17. Three-dimensional structure of laser-modified Ti6Al4V and bone interface revealed with STEM tomography

    International Nuclear Information System (INIS)

    The early interaction between an implant's surface and bone is a leading factor for implant success, where multiple surface properties contribute to improved bone anchorage. An important parameter is surface topography, both on the micron and nanoscale. Laser-modification has been performed in the thread valleys of Ti6Al4V screws to alter their surface chemistry and topography to form a nanostructured surface titanium-dioxide. Implants were placed in the rabbit tibia, removed with surrounding bone after 8 weeks, fixated, dried and resin embedded. Focused ion beam milling (FIB) was used to prepare specimens from the resin blocks for transmission electron microscopy (TEM). Z-contrast electron tomography offered the possibility to explore the interfacial structure with high-resolution in three-dimensions. With this technique, collagen fibers of the surrounding bone appear to have been laid down parallel to the implant surface. Accordingly, visualization of the laser-modified interface with nanoscale three-dimensional resolution, as offered by Z-contrast electron tomography, gives new insights into bone bonding mechanisms between roughened titanium-dioxide surfaces and bone

  18. The three dimensional dynamic structure of the inner Orion Nebula

    CERN Document Server

    O'Dell, C R; Abel, N P; Ferland, G J; Arthur, S J

    2008-01-01

    The three dimensional structure of the brightest part of the Orion Nebula is assessed in the light of published and new data. We find that the widely accepted model of a concave blister of ionized material needs to be altered in the southwest direction from the Trapezium, where we find that the Orion-S feature is a separate cloud of very optically thick molecules within the body of ionized gas, which is probably the location of the multiple embedded sources that produce the outflows that define the Orion-S star formation region. Evidence for this cloud comes from the presence of H2CO lines in absorption in the radio continuum and discrepancies in the extinction derived from radio-optical and optical only emission. We present an equilibrium Cloudy model of the Orion-S cloud, which successfully reproduces many observed properties of this feature. We also report the discovery of an open-sided shell of [O III] surrounding the Trapezium stars, revealed through emission line ratio images and the onset of radiation ...

  19. Self-organization in three-dimensional compressible magnetohydrodynamic flow

    International Nuclear Information System (INIS)

    A three-dimensional self-organization process of a compressible dissipative plasma with a velocity-magnetic field correlation is investigated in detail by means of a variational method and a magnetohydrodynamic simulation. There are two types of relaxation, i.e., fast relaxation in which the cross helicity is not conserved, and slow relaxation in which the cross helicity is approximately conserved. In the slow relaxation case the cross helicity consists of two components with opposite sign which have almost the same amplitude in the large wavenumber region. In both cases the system approaches a high correlation state, dependent on the initial condition. These results are consistent with an observational data of the solar wind. Selective dissipation of magnetic energy, normal cascade of magnetic energy spectrum and inverse cascade of magnetic helicity spectrum are observed for the sub-Alfvenic flow case as was previously observed for the zero flow case. When the flow velocity is super-Alfvenic, the relaxation process is significantly altered from the zero flow case. (author)

  20. Three-Dimensional Virtual Worlds: Research Trends and Future Directions

    Directory of Open Access Journals (Sweden)

    Saniye Tuğba TOKEL

    2014-05-01

    Full Text Available Use of three-dimensional virtual world platforms has been increasing worldwide. These online multi-user spaces, where users move and interact in a simulated three-dimensional spaces, provide many opportunities for learning and teaching process. Educators worldwide have been experimenting to use these technologies by investing on research and development. The purpose of this study is to analyze research trends in three-dimensional virtual world literature. The results of the study will provide a roadmap to the researchers and educators who wants to use these environments for an educational purposes.

  1. The bottleneck effect in three-dimensional turbulence simulations

    CERN Document Server

    Dobler, W; Yousef, T A; Brandenburg, A; Dobler, Wolfgang; Haugen, Nils Erland L.; Yousef, Tarek A.; Brandenburg, Axel

    2003-01-01

    At numerical resolutions around $512^3$ and above, three-dimensional energy spectra from turbulence simulations begin to show noticeably shallower spectra than $k^{-5/3}$ near the Kolmogorov dissipation wavenumber (`bottleneck effect'). This effect is shown to be significantly weaker in one-dimensional spectra like those obtained in wind tunnel turbulence. The difference can be understood in terms of the transformation between one-dimensional and three-dimensional energy spectra under the assumption that the turbulent velocity field is isotropic. Transversal and longitudinal energy spectra are similar and can both accurately be computed from the full three-dimensional spectra.

  2. Robust three dimensional surface contouring method with digital holography

    Institute of Scientific and Technical Information of China (English)

    YUAN Cao-jin; ZHAI Hong-chen; WANG Xiao-lei; WU Lan

    2006-01-01

    In this paper,a digital holography system with short-coherence light source is used to record a series of holograms of a micro-object. The three dimensional reconstruction is completed by the least-square-polynomial-fitting with a series of two dimensional intensity images which are obtained through holographic reconstruction. This three dimensional reconstruction method can be used to carry out three-dimensional reconstruction of a micro-object with strong laser speckle noise,which can not be obtained from the conventional method.

  3. Direct three-dimensional patterning using nanoimprint lithography

    Science.gov (United States)

    Li, Mingtao; Chen, Lei; Chou, Stephen Y.

    2001-05-01

    We demonstrated that nanoimprint lithography (NIL) can create three-dimensional patterns, sub-40 nm T-gates, and air-bridge structures, in a single step imprint in polymer and metal by lift-off. A method based on electron beam lithography and reactive ion etching was developed to fabricate NIL molds with three-dimensional protrusions. The low-cost and high-throughput nanoimprint lithography for three-dimensional nanostructures has many significant applications such as monolithic microwave integrated circuits and nanoelectromechanical system.

  4. Engineering an Integrated Cellular Interface in Three-Dimensional Hydrogel Cultures Permits Monitoring of Reciprocal Astrocyte and Neuronal Responses*

    OpenAIRE

    East, Emma; Golding, Jon P.; Phillips, James B.

    2012-01-01

    This study reports a new type of three-dimensional (3D) tissue model for studying interactions between cell types in collagen hydrogels. The aim was to create a 3D cell culture model containing separate cell populations in close proximity without the presence of a mechanical barrier, and demonstrate its relevance to modeling the axon growth-inhibitory cellular interfaces that develop in the central nervous system (CNS) in response to damage. This provides a powerful new tool to determine whic...

  5. Three-dimensional computer simulation of grain coarsening during sintering

    OpenAIRE

    Nikolic Zoran S.

    2012-01-01

    This paper presents a computational study of the three-dimensional computer simulation of grain coarsening using a sintering model based on sintering law (a rate law of inter-grain distance reduction) describing the evolution of neck geometry.

  6. A simple remark on three dimensional gauge theories

    International Nuclear Information System (INIS)

    Classical three dimensional Yang-Mills is seen to be related to the topological Chern-Simons term through a nonlinear but fully local and covariant gauge field redefinition. A classical recursive cohomological argument is proved. (author)

  7. Improving Students' Sense of Three-Dimensional Shapes.

    Science.gov (United States)

    Leeson, Neville J.

    1994-01-01

    Describes activities to be used with fifth and sixth graders to improve students' spatial sense with respect to three-dimensional shapes. Includes the use of cubes, triangular prisms, tetrahedrons, and square pyramids. (MKR)

  8. Three-dimensional reconstructions of solid surfaces using conventional microscopes.

    Science.gov (United States)

    Ficker, Tomáš; Martišek, Dalibor

    2016-01-01

    The three-dimensional digital replicas of solid surfaces are subject of interest of different branches of science and technology. The present paper in its introductory parts brings an overview of the various microscopic reconstructive techniques based on optical sectioning. The main attention is devoted to conventional reconstruction methods and especially to that one employing the Fourier transform. The three-dimensional replicas of this special reconstructive frequency method are compared graphically and numerically with the three-dimensional replicas of the confocal method. Based on the comparative study it has been concluded that the quality of the conventional replicas of surfaces possessing textures of intermediate height irregularities is acceptable and almost comparable with the quality of confocal replicas. This study is relevant both for identifying a convenient technique that provides good qualities of three-dimensional replicas and for selecting the hardware whose price is affordable even for small research groups studying rougher surface textures. PMID:26381761

  9. Automated pattern extraction and three-dimensional construction

    International Nuclear Information System (INIS)

    Computed tomography equipment provides cross sectional images of human bodies. From these two-dimensional images, doctors can extract useful information for diagnosis. Possibilities of contour extraction and three-dimensional construction of objective regions of affected parts (dilated ventricles) have been investigated on the basis of brain CT images. The perspectives of extracted three-dimensional objects are dynamically displayed on a three-dimensional graphic display system and following conclusions have been obtained. (1) Three-dimensional images provide helpful information for recognizing the shapes of objective regions of affected parts of a brain. (2) The volume and cross sectional area of the object of interest are available from this system. Especially the volumetric ratio of dilated ventricles to cranium has the possibility of becoming a better measure than the conventional one. (author)

  10. Analysis and validation of carbohydrate three-dimensional structures

    International Nuclear Information System (INIS)

    The article summarizes the information that is gained from and the errors that are found in carbohydrate structures in the Protein Data Bank. Validation tools that can locate these errors are described. Knowledge of the three-dimensional structures of the carbohydrate molecules is indispensable for a full understanding of the molecular processes in which carbohydrates are involved, such as protein glycosylation or protein–carbohydrate interactions. The Protein Data Bank (PDB) is a valuable resource for three-dimensional structural information on glycoproteins and protein–carbohydrate complexes. Unfortunately, many carbohydrate moieties in the PDB contain inconsistencies or errors. This article gives an overview of the information that can be obtained from individual PDB entries and from statistical analyses of sets of three-dimensional structures, of typical problems that arise during the analysis of carbohydrate three-dimensional structures and of the validation tools that are currently available to scientists to evaluate the quality of these structures

  11. Magnetic structure of two- and three-dimensional supramolecular compounds

    Energy Technology Data Exchange (ETDEWEB)

    Decurtins, S.; Schmalle, H.W.; Pellaux, R. [Zurich Univ. (Switzerland); Fischer, P.; Fauth, F. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Ouladdiaf, B. [Institut Max von Laue - Paul Langevin, 75 - Paris (France)

    1997-09-01

    Supramolecular chiral networks of oxalato-bridged transition metals show either two- or three-dimensional structural features. The magnetic structures of such compounds have been investigated by means of elastic neutron powder diffraction. (author) 2 figs., 2 refs.

  12. Feynman diagams coupled to three-dimensional quantum gravity

    OpenAIRE

    Barrett, John W.

    2005-01-01

    A framework for quantum field theory coupled to three-dimensional quantum gravity is proposed. The coupling with quantum gravity regulates the Feynman diagrams. One recovers the usual Feynman amplitudes in the limit as the cosmological constant tends to zero.

  13. Three-dimensional X-ray micro-velocimetry

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Wah-Keat, E-mail: wklee@aps.anl.gov; Fezzaa, Kamel [Advanced Photon Source, Argonne National Laboratory, Argonne, IL 60439 (United States); Uemura, Tomomasa [Kansai University, 3-3 Yamate, Suita, Osaka 564-8680 (Japan)

    2011-03-01

    Three-dimensional X-ray velocimetry with micrometer-level resolution is demonstrated. A direct measurement of three-dimensional X-ray velocimetry with micrometer spatial resolution is presented. The key to this development is the use of a Laue crystal as an X-ray beam splitter and mirror. Three-dimensional flow velocities in a 0.4 mm-diameter tubing were recorded, with <5 µm spatial resolution and speeds of 0.7 mm s{sup −1}. This development paves the way for three-dimensional velocimetry in many cases where visible-light techniques are not effective, such as multiphase flow or flow of optically opaque liquids.

  14. Direct Linear Transformation Method for Three-Dimensional Cinematography

    Science.gov (United States)

    Shapiro, Robert

    1978-01-01

    The ability of Direct Linear Transformation Method for three-dimensional cinematography to locate points in space was shown to meet the accuracy requirements associated with research on human movement. (JD)

  15. Collagen reorganization at the tumor-stromal interface facilitates local invasion

    Directory of Open Access Journals (Sweden)

    Inman David R

    2006-12-01

    Full Text Available Abstract Background Stromal-epithelial interactions are of particular significance in breast tissue as misregulation of these interactions can promote tumorigenesis and invasion. Moreover, collagen-dense breast tissue increases the risk of breast carcinoma, although the relationship between collagen density and tumorigenesis is not well understood. As little is known about epithelial-stromal interactions in vivo, it is necessary to visualize the stroma surrounding normal epithelium and mammary tumors in intact tissues to better understand how matrix organization, density, and composition affect tumor formation and progression. Methods Epithelial-stromal interactions in normal mammary glands, mammary tumors, and tumor explants in three-dimensional culture were studied with histology, electron microscopy, and nonlinear optical imaging methodologies. Imaging of the tumor-stromal interface in live tumor tissue ex vivo was performed with multiphoton laser-scanning microscopy (MPLSM to generate multiphoton excitation (MPE of endogenous fluorophores and second harmonic generation (SHG to image stromal collagen. Results We used both laser-scanning multiphoton and second harmonic generation microscopy to determine the organization of specific collagen structures around ducts and tumors in intact, unfixed and unsectioned mammary glands. Local alterations in collagen density were clearly seen, allowing us to obtain three-dimensional information regarding the organization of the mammary stroma, such as radiating collagen fibers that could not have been obtained using classical histological techniques. Moreover, we observed and defined three tumor-associated collagen signatures (TACS that provide novel markers to locate and characterize tumors. In particular, local cell invasion was found predominantly to be oriented along certain aligned collagen fibers, suggesting that radial alignment of collagen fibers relative to tumors facilitates invasion. Consistent

  16. Algebraic Ricci Solitons of three-dimensional Lorentzian Lie groups

    OpenAIRE

    Batat, Wafaa; Onda, Kensuke

    2011-01-01

    We classify Algebraic Ricci Solitons of three-dimensional Lorentzian Lie groups. All algebraic Ricci solitons that we obtain are sol-solitons. In particular, we prove that, contrary to the Riemannian case, Lorentzian Ricci solitons need not to be algebraic Ricci solitons. We classify Algebraic Ricci Solitons of three-dimensional Lorentzian Lie groups. All algebraic Ricci solitons that we obtain are solvsolitons. In particular, we obtain new solitons on $G_{2}$, $G_{5}$, and $G_{6}$, and we pr...

  17. Three-dimensional Quantum Polarization Tomography of Macroscopic Bell States

    CERN Document Server

    Kanseri, Bhaskar; Agafonov, Ivan; Chekhova, Maria; Leuchs, Gerd

    2011-01-01

    The polarization properties of macroscopic Bell states are characterized using three-dimensional quantum polarization tomography. This method utilizes three-dimensional inverse Radon transform to reconstruct the polarization quasiprobability distribution function of a state from the probability distributions measured for various Stokes observables. The reconstructed 3D distributions obtained for the macroscopic Bell states are compared with those obtained for a coherent state with the same mean photon number. The results demonstrate squeezing in one or more Stokes observables.

  18. Uniform Deterministic Discrete Method for Three Dimensional Systems

    Institute of Scientific and Technical Information of China (English)

    1997-01-01

    For radiative direct exchange areas in three dimensional system,the Uniform Deterministic Discrete Method(UDDM) was adopted.The spherical surface dividing method for sending area element and the regular icosahedron for sending volume element can meet with the direct exchange area computation of any kind of zone pairs.The numerical examples of direct exchange area in three dimensional system with nonhomogeneous attenuation coefficients indicated that the UDDM can give very high numercal accuracy.

  19. Fermionic Casimir energy in a three-dimensional box

    International Nuclear Information System (INIS)

    In this paper we calculate the Casimir energy for a massless fermionic field confined inside a three-dimensional rectangular box. We use the MIT bag model boundary condition for the confinement. We use the direct mode summation method along with the Abel-Plana summation formula to compute the Casimir energy, without any use of regularization or analytic continuation techniques. We obtain a negative Casimir energy, as opposed to the previously reported result for the interior of a three-dimensional sphere.

  20. Three-dimensional study of the multi-cavity FEL

    Energy Technology Data Exchange (ETDEWEB)

    Krishnagopal, S.; Kumar, V. [Centre for Advanced Technology, Indore (India)

    1995-12-31

    The Multi-Cavity Free-Electron Laser has been proposed earlier, as a new configuration to obtain short, intense pulses of radiation, the key idea being to pre-bunch the electron beam in a number of very short cavities. Those studies were one-dimensional. Here we use three-dimensional simulations to study the viability of this concept when three-dimensional effects are included, particularly with regard to the transverse modes of the optical beam.

  1. Three-Dimensional Percolation Modeling of Self-Healing Composites

    OpenAIRE

    Dementsov, A.; Privman, V.

    2008-01-01

    We study the self-healing process of materials with embedded "glue"-carrying cells, in the regime of the onset of the initial fatigue. Three-dimensional numerical simulations within the percolation-model approach are reported. The main numerical challenge taken up in the present work, has been to extend the calculation of the conductance to three-dimensional lattices. Our results confirm the general features of the process: The onset of the material fatigue is delayed, by developing a plateau...

  2. On-Chip Isotropic Microchannels for Cooling Three Dimensional Microprocessors

    OpenAIRE

    Renaghan, Liam Eamon

    2009-01-01

    This thesis reports the fabrication of three dimensionally independent on-chip microchannels using a CMOS-compatible single mask deep reactive ion etching (DRIE) process for cooling 3D ICs. Three dimensionally independent microchannels are fabricated by utilizing the RIE lag effect. This allows complex microchannel configurations to be fabricated using a single mask and single silicon etch step. Furthermore, the microchannels are sealed in one step by low temperature oxide deposition. The mic...

  3. Three-dimensional reconstruction of functional brain images

    International Nuclear Information System (INIS)

    We consider PET (positron emission tomography) measurement with SPM (Statistical Parametric Mapping) analysis to be one of the most useful methods to identify activated areas of the brain involved in language processing. SPM is an effective analytical method that detects markedly activated areas over the whole brain. However, with the conventional presentations of these functional brain images, such as horizontal slices, three directional projection, or brain surface coloring, makes understanding and interpreting the positional relationships among various brain areas difficult. Therefore, we developed three-dimensionally reconstructed images from these functional brain images to improve the interpretation. The subjects were 12 normal volunteers. The following three types of images were constructed: routine images by SPM, three-dimensional static images, and three-dimensional dynamic images, after PET images were analyzed by SPM during daily dialog listening. The creation of images of both the three-dimensional static and dynamic types employed the volume rendering method by VTK (The Visualization Toolkit). Since the functional brain images did not include original brain images, we synthesized SPM and MRI brain images by self-made C++ programs. The three-dimensional dynamic images were made by sequencing static images with available software. Images of both the three-dimensional static and dynamic types were processed by a personal computer system. Our newly created images showed clearer positional relationships among activated brain areas compared to the conventional method. To date, functional brain images have been employed in fields such as neurology or neurosurgery, however, these images may be useful even in the field of otorhinolaryngology, to assess hearing and speech. Exact three-dimensional images based on functional brain images are important for exact and intuitive interpretation, and may lead to new developments in brain science. Currently, the surface

  4. Three-dimensional stochastic seepage field for embankment engineering

    OpenAIRE

    WANG, YA-JUN; Wo-hua ZHANG; Wu, Chang-Yu; Da-chun REN

    2009-01-01

    Owing to the complexity of geo-engineering seepage problems influenced by different random factors, three-dimensional simulation and analysis of the stochastic seepage field plays an important role in engineering applications. A three-dimensional anisotropic heterogeneous steady random seepage model was developed on the basis of the finite element method. A statistical analysis of the distribution characteristics of soil parameters sampled from the main embankment of the Yangtze River in the ...

  5. Three-dimensional reconstruction of functional brain images

    Energy Technology Data Exchange (ETDEWEB)

    Inoue, Masato; Shoji, Kazuhiko; Kojima, Hisayoshi; Hirano, Shigeru; Naito, Yasushi; Honjo, Iwao [Kyoto Univ. (Japan)

    1999-08-01

    We consider PET (positron emission tomography) measurement with SPM (Statistical Parametric Mapping) analysis to be one of the most useful methods to identify activated areas of the brain involved in language processing. SPM is an effective analytical method that detects markedly activated areas over the whole brain. However, with the conventional presentations of these functional brain images, such as horizontal slices, three directional projection, or brain surface coloring, makes understanding and interpreting the positional relationships among various brain areas difficult. Therefore, we developed three-dimensionally reconstructed images from these functional brain images to improve the interpretation. The subjects were 12 normal volunteers. The following three types of images were constructed: routine images by SPM, three-dimensional static images, and three-dimensional dynamic images, after PET images were analyzed by SPM during daily dialog listening. The creation of images of both the three-dimensional static and dynamic types employed the volume rendering method by VTK (The Visualization Toolkit). Since the functional brain images did not include original brain images, we synthesized SPM and MRI brain images by self-made C++ programs. The three-dimensional dynamic images were made by sequencing static images with available software. Images of both the three-dimensional static and dynamic types were processed by a personal computer system. Our newly created images showed clearer positional relationships among activated brain areas compared to the conventional method. To date, functional brain images have been employed in fields such as neurology or neurosurgery, however, these images may be useful even in the field of otorhinolaryngology, to assess hearing and speech. Exact three-dimensional images based on functional brain images are important for exact and intuitive interpretation, and may lead to new developments in brain science. Currently, the surface

  6. Stromal matrix metalloprotease-13 knockout alters Collagen I structure at the tumor-host interface and increases lung metastasis of C57BL/6 syngeneic E0771 mammary tumor cells

    International Nuclear Information System (INIS)

    Matrix metalloproteases and collagen are key participants in breast cancer, but their precise roles in cancer etiology and progression remain unclear. MMP13 helps regulate collagen structure and has been ascribed largely harmful roles in cancer, but some studies demonstrate that MMP13 may also protect against tumor pathology. Other studies indicate that collagen’s organizational patterns at the breast tumor-host interface influence metastatic potential. Therefore we investigated how MMP13 modulates collagen I, a principal collagen subtype in breast tissue, and affects tumor pathology and metastasis in a mouse model of breast cancer. Tumors were implanted into murine mammary tissues, and their growth analyzed in Wildtype and MMP13 KO mice. Following extraction, tumors were analyzed for collagen I levels and collagen I macro- and micro-structural properties at the tumor-host boundary using immunocytochemistry and two-photon and second harmonic generation microscopy. Lungs were analyzed for metastases counts, to correlate collagen I changes with a clinically significant functional parameter. Statistical analyses were performed by t-test, analysis of variance, or Wilcoxon-Mann–Whitney tests as appropriate. We found that genetic ablation of host stromal MMP13 led to: 1. Increased mammary tumor collagen I content, 2. Marked changes in collagen I spatial organization, and 3. Altered collagen I microstructure at the tumor-host boundary, as well as 4. Increased metastasis from the primary mammary tumor to lungs. These results implicate host MMP13 as a key regulator of collagen I structure and metastasis in mammary tumors, thus making it an attractive potential therapeutic target by which we might alter metastatic potential, one of the chief determinants of clinical outcome in breast cancer. In addition to identifying stromal MMP13 is an important regulator of the tumor microenvironment and metastasis, these results also suggest that stromal MMP13 may protect against

  7. Three-dimensional decomposition method of global atmospheric circulation

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    By adopting the idea of three-dimensional Walker, Hadley and Rossby stream functions, the global atmospheric circulation can be considered as the sum of three stream functions from a global per- spective. Therefore, a mathematical model of three-dimensional decomposition of global atmospheric circulation is proposed and the existence and uniqueness of the model are proved. Besides, the model includes a numerical method leading to no truncation error in the discrete three-dimensional grid points. Results also show that the three-dimensional stream functions exist and are unique for a given velocity field. The mathematical model shows the generalized form of three-dimensional stream func- tions equal to the velocity field in representing the features of atmospheric motion. Besides, the vertical velocity calculated through the model can represent the main characteristics of the vertical motion. In sum, the three-dimensional decomposition of atmospheric circulation is convenient for the further in- vestigation of the features of global atmospheric motions.

  8. Integrated Aeromechanics with Three-Dimensional Solid-Multibody Structures

    Science.gov (United States)

    Datta, Anubhav; Johnson, Wayne

    2014-01-01

    A full three-dimensional finite element-multibody structural dynamic solver is coupled to a three-dimensional Reynolds-averaged Navier-Stokes solver for the prediction of integrated aeromechanical stresses and strains on a rotor blade in forward flight. The objective is to lay the foundations of all major pieces of an integrated three-dimensional rotor dynamic analysis - from model construction to aeromechanical solution to stress/strain calculation. The primary focus is on the aeromechanical solution. Two types of three-dimensional CFD/CSD interfaces are constructed for this purpose with an emphasis on resolving errors from geometry mis-match so that initial-stage approximate structural geometries can also be effectively analyzed. A three-dimensional structural model is constructed as an approximation to a UH-60A-like fully articulated rotor. The aerodynamic model is identical to the UH-60A rotor. For preliminary validation measurements from a UH-60A high speed flight is used where CFD coupling is essential to capture the advancing side tip transonic effects. The key conclusion is that an integrated aeromechanical analysis is indeed possible with three-dimensional structural dynamics but requires a careful description of its geometry and discretization of its parts.

  9. Three-dimensional semi-automated segmentation of carotid atherosclerosis from three-dimensional ultrasound images

    Science.gov (United States)

    Ukwatta, E.; Awad, J.; Buchanan, D.; Parraga, G.; Fenster, A.

    2012-03-01

    Three-dimensional ultrasound (3DUS) provides non-invasive and precise measurements of carotid atherosclerosis that directly reflects arterial wall abnormalities that are thought to be related to stroke risk. Here we describe a threedimensional segmentation method based on the sparse field level set method to automate the segmentation of the mediaadventitia (MAB) and lumen-intima (LIB) boundaries of the common carotid artery from 3DUS images. To initiate the process, an expert chooses four anchor points on each boundary on a subset of transverse slices that are orthogonal to the axis of the artery. An initial surface is generated using the anchor points as initial guess for the segmentation. The MAB is segmented first using five energies: length minimization energy, local region-based energy, edge-based energy, anchor point-based energy, and local smoothness energy. Five energies are also used for the LIB segmentation: length minimization energy, local region-based energy, global region-based energy, anchor point-based energy, and boundary separation-based energy. The algorithm was evaluated with respect to manual segmentations on a slice-by-slice basis using 15 3DUS images. To generate results in this paper, inter-slice distance of 2 mm is used for the initialization. For the MAB and LIB segmentations, our method yielded Dice coefficients of more than 92% and sub-millimeter values for mean and maximum absolute distance errors. Our method also yielded a vessel wall volume error of 7.1% +/- 3.4%. The realization of a semi-automated algorithm will aid in the translation of 3DUS measurements to clinical research for the rapid, non-invasive, and economical monitoring of atherosclerotic disease.

  10. Three Dimensional Virtual Environments as a Tool for Development of Personal Learning Networks

    OpenAIRE

    Aggeliki Nikolaou; Costas Tsolakidis

    2013-01-01

    Technological advances have altered how, where, when, and what information is created, presented and diffused in working and social environments as well as how learners interact with that information. Virtual worlds constitute an emerging realm for collaborative play, learning and work. This paper describes how virtual worlds provide a mechanism to facilitate the creation and development of Personal Learning Networks. This qualitative investigation focuses on the role of three-dimensional vir...

  11. A mathematical model for three dimensional detonation as pure gas-dynamic discontinuity

    OpenAIRE

    Escanciano, Jorge Yanez; Class, Andreas G.

    2012-01-01

    A model for three dimensional detonation is proposed based on the approximation that the detonation thickness is small compared to the characteristic scales of the fluid motion. In this framework detonations are treated as a modified hydrodynamic discontinuity. The altered Rankine-Hugoniot jump conditions take into account the internal structure of the detonation including the chemical reaction. The position of the discontinuity surface and the corresponding jump conditions are derived from f...

  12. Off-center ratios for three-dimensional dose calculations

    International Nuclear Information System (INIS)

    A new method is proposed for computing the off-center ratios (OCR's) in three-dimensional dose calculations. For an open field, the OCR at a point is computed as the product of the primary OCR (POCR) and the boundary factors (BF's). The POCR describes the beam profile for an infinite field, that is, without the effect of the collimators. It is defined as the ratio of the dose at a point off the central ray to the dose at the point on the central ray at the same depth for an infinite field. The POCR is a function of radial distance from the beam central ray and depth. The BF describes the shape of the beam in the neighborhood of the field boundary defined by the collimators. It is defined as the ratio of the OCR at a point for a finite field to the OCR at the same point for an infinite field. The BF is a function of distance from the field boundary, depth, and field size. For a wedged field, we assume that the boundary factors remain the same as for open fields but the POCR's are altered. The changes in beam profiles are described by a factor called the wedge profile factor (WPF), defined as the ratio of the dose at a point for the largest wedged field to the dose at the same point for an open field of the same field size. The WPF is a function of lateral distance from the beam central plane and depth. Calculated OCR's using this new method are in agreement with the measured data along both the transverse and the diagonal directions of the field

  13. Three-dimensionality effects in flow around two tandem cylinders

    Science.gov (United States)

    Papaioannou, Georgios V.; Yue, Dick K. P.; Triantafyllou, Michael S.; Karniadakis, George E.

    2006-07-01

    The flow around two stationary cylinders in tandem arrangement at the laminar and early turbulent regime, (Re {=} 10(2) 10(3) ), is studied using two- and three-dimensional direct numerical simulations. A range of spacings between the cylinders from 1.1 to 5.0 diameters is considered with emphasis on identifying the effects of three-dimensionality and cylinder spacing as well as their coupling. To achieve this, we compare the two-dimensional with corresponding three-dimensional results as well as the tandem cylinder system results with those of a single cylinder. The critical spacing for vortex formation and shedding in the gap region depends on the Reynolds number. This dependence is associated with the formation length and base pressure suction variations of a single cylinder with Reynolds number. This association is useful in explaining some of the discrepancies between the two-dimensional and three-dimensional results. A major effect of three-dimensionality is in the exact value of the critical spacing, resulting in deviations from the two-dimensional predictions for the vorticity fields, the forces on the downstream cylinder, and the shedding frequency of the tandem system. Two-dimensional simulations under-predict the critical spacing, leading to erroneous results for the forces and shedding frequencies over a range of spacings where the flow is qualitatively different. To quantify the three-dimensional effects we first employ enstrophy, decomposed into a primary and a secondary component. The primary component involves the vorticity parallel to the cylinder axis, while the secondary component incorporates the streamwise and transverse components of the vorticity vector. Comparison with the single cylinder case reveals that the presence of the downstream cylinder at spacings lower than the critical value has a stabilizing effect on both the primary and secondary enstrophy. Systematic quantification of three-dimensionalities involves finding measures for the

  14. Dermatan Sulfate Epimerase 1-Deficient Mice Have Reduced Content and Changed Distribution of Iduronic Acids in Dermatan Sulfate and an Altered Collagen Structure in Skin

    DEFF Research Database (Denmark)

    Maccarana, M.; Kalamajski, S.; Kongsgaard, M.; Magnusson, S.P.; Oldberg, A.; Malmstrom, A.

    2009-01-01

    Dermatan sulfate epimerase 1 (DS-epi1) and DS-epi2 convert glucuronic acid to iduronic acid in chondroitin/dermatan sulfate biosynthesis. Here we report on the generation of DS-epi1-null mice and the resulting alterations in the chondroitin/dermatan polysaccharide chains. The numbers of long blocks...... of adjacent iduronic acids are greatly decreased in skin decorin and biglycan chondroitin/dermatan sulfate, along with a parallel decrease in iduronic-2-O-sulfated-galactosamine-4-O-sulfated structures. Both iduronic acid blocks and iduronic acids surrounded by glucuronic acids are also decreased in...... versican-derived chains. DS-epi1-deficient mice are smaller than their wild-type littermates but otherwise have no gross macroscopic alterations. The lack of DS-epi1 affects the chondroitin/dermatan sulfate in many proteoglycans, and the consequences for skin collagen structure were initially analyzed. We...

  15. Characterization of human lung cancer-associated fibroblasts in three-dimensional in vitro co-culture model

    International Nuclear Information System (INIS)

    Highlights: ► We established three patient-paired sets of CAFs and NFs. ► CAFs and NFs were analyzed using three-dimensional co-culture experiments. ► CAFs clearly enhanced collagen gel contraction. ► CAFs showed higher α-SMA expression than NFs. ► CAFs were implicated in invasion and differentiation of lung cancer cells. -- Abstract: Lung cancer is the most common cause of cancer-related death worldwide. Stromal cancer-associated fibroblasts (CAFs) play crucial roles in carcinogenesis, proliferation, invasion, and metastasis of non-small cell lung carcinoma, and targeting of CAFs could be a novel strategy for cancer treatment. However, the characteristics of human CAFs still remain to be better defined. In this study, we established patient-matched CAFs and normal fibroblasts (NFs), from tumoral and non-tumoral portions of resected lung tissue from lung cancer patients. CAFs showed higher α-smooth muscle actin (α-SMA) expression than NFs, and CAFs clearly enhanced collagen gel contraction. Furthermore, we employed three-dimensional co-culture assay with A549 lung cancer cells, where CAFs were more potent in inducing collagen gel contraction. Hematoxylin and eosin staining of co-cultured collagen gel revealed that CAFs had the potential to increase invasion of A549 cells compared to NFs. These observations provide evidence that lung CAFs have the tumor-promoting capacity distinct from NFs.

  16. Characterizing natural hydrogel for reconstruction of three-dimensional lymphoid stromal network to model T-cell interactions.

    Science.gov (United States)

    Kim, Jiwon; Wu, Biming; Niedzielski, Steven M; Hill, Matthew T; Coleman, Rhima M; Ono, Akira; Shikanov, Ariella

    2015-08-01

    Hydrogels have been used in regenerative medicine because they provide a three-dimensional environment similar to soft tissues, allow diffusion of nutrients, present critical biological signals, and degrade via endogenous enzymatic mechanisms. Herein, we developed in vitro system mimicking cell-cell and cell-matrix interactions in secondary lymphoid organs (SLOs). Existing in vitro culture systems cannot accurately represent the complex interactions happening between T-cells and stromal cells in immune response. To model T-cell interaction in SLOs in vitro, we encapsulated stromal cells in fibrin, collagen, or fibrin-collagen hydrogels and studied how different mechanical and biological properties affect stromal network formation. Overall, fibrin supplemented with aprotinin was superior to collagen and fibrin-collagen in terms of network formation and promotion of T-cell penetration. After 8 days of culture, stromal networks formed through branching and joining with other adjacent cell populations. T-cells added to the newly formed stromal networks migrated and attached to stromal cells, similar to the T-cell zones of the lymph nodes in vivo. Our results suggest that the constructed three-dimensional lymphoid stromal network can mimic the in vivo environment and allow the modeling of T-cell interaction in SLOs. PMID:25649205

  17. Three-dimensional magnetospheric equilibrium with isotropic pressure

    International Nuclear Information System (INIS)

    In the absence of the toroidal flux, two coupled quasi two-dimensional elliptic equilibrium equations have been derived to describe self-consistent three-dimensional static magnetospheric equilibria with isotropic pressure in an optimal (Ψ,α,χ) flux coordinate system, where Ψ is the magnetic flux function, χ is a generalized poloidal angle, α is the toroidal angle, α = φ - δ(Ψ,φ,χ) is the toroidal angle, δ(Ψ,φ,χ) is periodic in φ, and the magnetic field is represented as rvec B = ∇Ψ x ∇α. A three-dimensional magnetospheric equilibrium code, the MAG-3D code, has been developed by employing an iterative metric method. The main difference between the three-dimensional and the two-dimensional axisymmetric solutions is that the field-aligned current and the toroidal magnetic field are finite for the three-dimensional case, but vanish for the two-dimensional axisymmetric case. With the same boundary flux surface shape, the two-dimensional axisymmetric results are similar to the three-dimensional magnetosphere at each local time cross section

  18. A moving observer in a three-dimensional world.

    Science.gov (United States)

    Glennerster, Andrew

    2016-06-19

    For many tasks such as retrieving a previously viewed object, an observer must form a representation of the world at one location and use it at another. A world-based three-dimensional reconstruction of the scene built up from visual information would fulfil this requirement, something computer vision now achieves with great speed and accuracy. However, I argue that it is neither easy nor necessary for the brain to do this. I discuss biologically plausible alternatives, including the possibility of avoiding three-dimensional coordinate frames such as ego-centric and world-based representations. For example, the distance, slant and local shape of surfaces dictate the propensity of visual features to move in the image with respect to one another as the observer's perspective changes (through movement or binocular viewing). Such propensities can be stored without the need for three-dimensional reference frames. The problem of representing a stable scene in the face of continual head and eye movements is an appropriate starting place for understanding the goal of three-dimensional vision, more so, I argue, than the case of a static binocular observer.This article is part of the themed issue 'Vision in our three-dimensional world'. PMID:27269608

  19. Robot vision based on three-dimensional model

    International Nuclear Information System (INIS)

    In order that robots recognize objects, the models of the objects are required. If there is not any constraint about an object scene, it is desirable that robot vision has the three-dimensional models of the things composing the scene. Since the preparation of three-dimensional models takes much time, here, the utilization of the geometrical models made by CAD is proposed. Besides, when the description of a scene and three-dimensional models are compared, to attempt the comparison with all attitudes of respective models is not efficient, therefore, stratum-wise comparison was proposed. As concrete examples, when input information is only in the direction of a part of surfaces such as lustrous bodies, when information can be obtained in all the directions of the surfaces of a body visible by a photometric stereo, and when complete three dimensional information is obtained by a distance-measuring instrument, the techniques of object recognition are described. In all cases, by carrying out the stratum-wise comparison based on three-dimensional models, the efficient and generalized object recognition was able to be achieved. (Kako, I.)

  20. Biodynamic profiling of three-dimensional tissue growth techniques

    Science.gov (United States)

    Sun, Hao; Merrill, Dan; Turek, John; Nolte, David

    2016-03-01

    Three-dimensional tissue culture presents a more biologically relevant environment in which to perform drug development than conventional two-dimensional cell culture. However, obtaining high-content information from inside three dimensional tissue has presented an obstacle to rapid adoption of 3D tissue culture for pharmaceutical applications. Biodynamic imaging is a high-content three-dimensional optical imaging technology based on low-coherence interferometry and digital holography that uses intracellular dynamics as high-content image contrast. In this paper, we use biodynamic imaging to compare pharmaceutical responses to Taxol of three-dimensional multicellular spheroids grown by three different growth techniques: rotating bioreactor, hanging-drop and plate-grown spheroids. The three growth techniques have systematic variations among tissue cohesiveness and intracellular activity and consequently display different pharmacodynamics under identical drug dose conditions. The in vitro tissue cultures are also compared to ex vivo living biopsies. These results demonstrate that three-dimensional tissue cultures are not equivalent, and that drug-response studies must take into account the growth method.

  1. Nonlinear microscopy of collagen fibers

    Science.gov (United States)

    Strupler, M.; Pena, A.-M.; Hernest, M.; Tharaux, P.-L.; Fabre, A.; Marchal-Somme, J.; Crestani, B.; Débarre, D.; Martin, J.-L.; Beaurepaire, E.; Schanne-Klein, M.-C.

    2007-02-01

    We used intrinsic Second Harmonic Generation (SHG) by fibrillar collagen to visualize the three-dimensional architecture of collagen fibrosis at the micrometer scale using laser scanning nonlinear microscopy. We showed that SHG signals are highly specific to fibrillar collagen and provide a sensitive probe of the micrometer-scale structural organization of collagen in tissues. Moreover, recording simultaneously other nonlinear optical signals in a multimodal setup, we visualized the tissue morphology using Two-Photon Excited Fluorescence (2PEF) signals from endogenous chromophores such as NADH or elastin. We then compared different methods to determine accurate indexes of collagen fibrosis using nonlinear microscopy, given that most collagen fibrils are smaller than the microscope resolution and that second harmonic generation is a coherent process. In order to define a robust method to process our three-dimensional images, we either calculated the fraction of the images occupied by a significant SHG signal, or averaged SHG signal intensities. We showed that these scores provide an estimation of the extension of renal and pulmonary fibrosis in murine models, and that they clearly sort out the fibrotic mice.

  2. Three-Dimensional Microgel Platform for the Production of Cell Factories Tailored for the Nucleus Pulposus.

    Science.gov (United States)

    Fontana, Gianluca; Srivastava, Akshay; Thomas, Dilip; Lalor, Pierce; Dockery, Peter; Pandit, Abhay

    2015-07-15

    Intradiscal injection of growth factors or cells has been shown to attenuate symptoms of intervertebral disc degeneration. However, different approaches are needed to overcome limitations such as short-term efficacy and leakage of the injected solutions. The current study aims at creating a platform for the realization of functional cell factories by using in parallel cell delivery and gene therapy approaches. Superfect, a transfecting agent, was used as nonviral gene vector because of its ability to form complexes with plasmid DNA (polyplexes). Polyplexes were loaded into collagen hollow microsphere reservoirs, and their ability to transfect cells was ascertained in vitro. Adipose-derived stem cells were then embedded in three-dimensional (3D) microgels composed of type II collagen/hyaluronan, which mimics the environmental cues typical of the healthy nucleus pulposus. These were functionalized with polyplex-loaded collagen hollow spheres and the secretion of the target protein was assessed quantitatively. Delivery of polyplexes from a reservoir system lowered their toxicity significantly while maintaining high levels of transfection in a monolayer culture. In 3D microgels, lower levels of transfection were observed, however; increasing levels of luciferase were secreted from the microgels over 7 days of culture. These results indicate that 3D microgels, functionalized with polyplex-loaded reservoirs offer a reliable platform for the production of cell factories that are able to manufacture targeted therapeutic proteins for regenerative therapies that have applications in nucleus pulposus repair. PMID:25290910

  3. Three-dimensional particle image velocimetry measurement technique

    International Nuclear Information System (INIS)

    The experimental flow visualization tool, Particle Image Velocimetry (PIV), is being used to determine the velocity field in two-dimensional fluid flows. In the past few years, the technique has been improved to allow the capture of flow fields in three dimensions. This paper describes changes which were made to two existing two-dimensional tracking algorithms to enable them to track three-dimensional PIV data. Results of the tests performed on these three-dimensional routines with synthetic data are presented. Experimental data was also used to test the tracking algorithms. The test setup which was used to acquire the three-dimensional experimental data is described, along with the results from both of the tracking routines which were used to analyze the experimental data. (author)

  4. Computational methods for three-dimensional microscopy reconstruction

    CERN Document Server

    Frank, Joachim

    2014-01-01

    Approaches to the recovery of three-dimensional information on a biological object, which are often formulated or implemented initially in an intuitive way, are concisely described here based on physical models of the object and the image-formation process. Both three-dimensional electron microscopy and X-ray tomography can be captured in the same mathematical framework, leading to closely-related computational approaches, but the methodologies differ in detail and hence pose different challenges. The editors of this volume, Gabor T. Herman and Joachim Frank, are experts in the respective methodologies and present research at the forefront of biological imaging and structural biology.   Computational Methods for Three-Dimensional Microscopy Reconstruction will serve as a useful resource for scholars interested in the development of computational methods for structural biology and cell biology, particularly in the area of 3D imaging and modeling.

  5. Projector recalibration of three-dimensional profilometry system.

    Science.gov (United States)

    Zhou, Ping; Yu, Yunlei; Cai, Guochao; Huang, Shuo

    2016-03-20

    In three-dimensional profilometry, the primary disadvantage of the monocular system equipped with a projector and a camera is that it is often highly dependent on the projector calibration. The projector calibration errors of the principal point and focal length are analyzed in this paper, and result in measuring the object deviation, including not only the rigid transformation, but also the scale transformation. Unfortunately, the deviation cannot be revealed by reprojection, the normal error analysis method. Here, a systematic recalibration method is proposed to correct the projector calibration errors of the principal point and focal length, where an accurate binocular three-dimensional measurement system is applied. The experimental results show that the method is effective. The three-dimensional measurement accuracy of the monocular system is improved approximately from 1.0 mm before projector recalibration to 0.10 mm afterward. PMID:27140565

  6. Ray tracing a three dimensional scene using a grid

    Science.gov (United States)

    Wald, Ingo; Ize, Santiago; Parker, Steven G; Knoll, Aaron

    2013-02-26

    Ray tracing a three-dimensional scene using a grid. One example embodiment is a method for ray tracing a three-dimensional scene using a grid. In this example method, the three-dimensional scene is made up of objects that are spatially partitioned into a plurality of cells that make up the grid. The method includes a first act of computing a bounding frustum of a packet of rays, and a second act of traversing the grid slice by slice along a major traversal axis. Each slice traversal includes a first act of determining one or more cells in the slice that are overlapped by the frustum and a second act of testing the rays in the packet for intersection with any objects at least partially bounded by the one or more cells overlapped by the frustum.

  7. Hydrofocusing Bioreactor for Three-Dimensional Cell Culture

    Science.gov (United States)

    Gonda, Steve R.; Spaulding, Glenn F.; Tsao, Yow-Min D.; Flechsig, Scott; Jones, Leslie; Soehnge, Holly

    2003-01-01

    The hydrodynamic focusing bioreactor (HFB) is a bioreactor system designed for three-dimensional cell culture and tissue-engineering investigations on orbiting spacecraft and in laboratories on Earth. The HFB offers a unique hydrofocusing capability that enables the creation of a low-shear culture environment simultaneously with the "herding" of suspended cells, tissue assemblies, and air bubbles. Under development for use in the Biotechnology Facility on the International Space Station, the HFB has successfully grown large three-dimensional, tissuelike assemblies from anchorage-dependent cells and grown suspension hybridoma cells to high densities. The HFB, based on the principle of hydrodynamic focusing, provides the capability to control the movement of air bubbles and removes them from the bioreactor without degrading the low-shear culture environment or the suspended three-dimensional tissue assemblies. The HFB also provides unparalleled control over the locations of cells and tissues within its bioreactor vessel during operation and sampling.

  8. Three-dimensional network of Drosophila brain hemisphere

    CERN Document Server

    Mizutani, Ryuta; Takeuchi, Akihisa; Uesugi, Kentaro; Suzuki, Yoshio

    2016-01-01

    The first step to understanding brain function is to determine the brain's network structure. We report a three-dimensional analysis of the brain network of the fruit fly Drosophila melanogaster by synchrotron-radiation tomographic microscopy. A skeletonized wire model of the left half of the brain network was built by tracing the three-dimensional distribution of X-ray absorption coefficients. The obtained models of neuronal processes were classified into groups on the basis of their three-dimensional structures. These classified groups correspond to neuronal tracts that send long-range projections or repeated structures of the optic lobe. The skeletonized model is also composed of neuronal processes that could not be classified into the groups. The distribution of these unclassified structures correlates with the distribution of contacts between neuronal processes. This suggests that neurons that cannot be classified into typical structures should play important roles in brain functions. The quantitative de...

  9. Radiation hardness of three-dimensional polycrystalline diamond detectors

    Energy Technology Data Exchange (ETDEWEB)

    Lagomarsino, Stefano, E-mail: lagomarsino@fi.infn.it; Sciortino, Silvio [National Institute of Nuclear Physics (INFN), Via B. Rossi, 1-3, 50019 Sesto Fiorentino (Italy); Department of Physics and Astronomy, University of Florence, Via G. Sansone 1, 50019 Sesto Fiorentino (Italy); Bellini, Marco [European Laboratory for Non-Linear Spectroscopy, Via Nello Carrara 1, 50019 Sesto Fiorentino (Italy); Istituto Nazionale di Ottica (INO-CNR), Largo Enrico Fermi 6, 50125 Firenze (Italy); Corsi, Chiara [Department of Physics and Astronomy, University of Florence, Via G. Sansone 1, 50019 Sesto Fiorentino (Italy); European Laboratory for Non-Linear Spectroscopy, Via Nello Carrara 1, 50019 Sesto Fiorentino (Italy); Cindro, Vladimir [Jozef Stefan Institute, Jamova cesta 39, 1000 Ljubljana (Slovenia); Kanxheri, Keida; Servoli, Leonello [National Institute of Nuclear Physics (INFN), Via A. Pascoli, 06123 Perugia (Italy); Department of Physics, University of Perugia, Via A. Pascoli, 06123 Perugia (Italy); Morozzi, Arianna [Department of Engineering, University of Perugia, Via G. Duranti 93, 06125 Perugia (Italy); Passeri, Daniele [National Institute of Nuclear Physics (INFN), Via A. Pascoli, 06123 Perugia (Italy); Department of Engineering, University of Perugia, Via G. Duranti 93, 06125 Perugia (Italy); Schmidt, Christian J. [GSI Helmholtzzentrum für Schwerionenforschung, Planckstraße 1, 64291 Darmstadt (Germany)

    2015-05-11

    The three-dimensional concept in particle detection is based on the fabrication of columnar electrodes perpendicular to the surface of a solid state radiation sensor. It permits to improve the radiation resistance characteristics of a material by lowering the necessary bias voltage and shortening the charge carrier path inside the material. If applied to a long-recognized exceptionally radiation-hard material like diamond, this concept promises to pave the way to the realization of detectors of unprecedented performances. We fabricated conventional and three-dimensional polycrystalline diamond detectors, and tested them before and after neutron damage up to 1.2 ×10{sup 16 }cm{sup −2}, 1 MeV-equivalent neutron fluence. We found that the signal collected by the three-dimensional detectors is up to three times higher than that of the conventional planar ones, at the highest neutron damage ever experimented.

  10. Three-dimensional Coherent Structures of Electrokinetic Instability

    CERN Document Server

    Demekhin, E A; Shelistov, V S

    2014-01-01

    A direct numerical simulation of the three-dimensional elektrokinetic instability near a charge selective surface (electric membrane, electrode, or system of micro-/nanochannels) is carried out and analyzed. A special finite-difference method was used for the space discretization along with a semi-implicit $3\\frac{1}{3}$-step Runge-Kutta scheme for the integration in time. The calculations employed parallel computing. Three characteristic patterns, which correspond to the overlimiting currents, are observed: (a) two-dimensional electroconvective rolls, (b) three-dimensional regular hexagonal structures, and (c) three-dimensional structures of spatiotemporal chaos, which are a combination of unsteady hexagons, quadrangles and triangles. The transition from (b) to (c) is accompanied by the generation of interacting two-dimensional solitary pulses.

  11. Coupled particle dispersion by three-dimensional vortex structures

    Energy Technology Data Exchange (ETDEWEB)

    Troutt, T.R.; Chung, J.N.; Crowe, C.T.

    1996-12-31

    The primary objective of this research program is to obtain understanding concerning the role of three-dimensional vortex structures in the dispersion of particles and droplets in free shear flows. This research program builds on previous studies which focused on the nature of particle dispersion in large scale quasi two-dimensional vortex structures. This investigation employs time dependent experimental and numerical techniques to provide information concerning the particulate dispersion produced by three dimensional vortex structures in free shear layers. The free shear flows investigated include modified plane mixing layers, and modified plane wakes. The modifications to these flows involve slight perturbations to the initiation boundary conditions such that three-dimensional vortex structures are rapidly generated by the experimental and numerical flow fields. Recent results support the importance of these vortex structures in the particle dispersion process.

  12. Three-dimensional simulations of resistance spot welding

    DEFF Research Database (Denmark)

    Nielsen, Chris Valentin; Zhang, Wenqi; Perret, William;

    2014-01-01

    This paper draws from the fundamentals of electro-thermo-mechanical coupling to the main aspects of finite element implementation and three-dimensional modelling of resistance welding. A new simulation environment is proposed in order to perform three-dimensional simulations and optimization of...... resistance welding together with the simulations of conventional and special-purpose quasi-static mechanical tests. Three-dimensional simulations of resistance welding consider the electrical, thermal, mechanical and metallurgical characteristics of the material as well as the operating conditions of the...... welding machines. Simulations of the mechanical tests take into account material softening due to the accumulation of ductile damage and cover conventional tests, such as tensile–shear tests, cross-tension test and peel tests, as well as the possibility of special-purpose tests designed by the users. The...

  13. In vivo, label-free, three-dimensional quantitative imaging of liver surface using multi-photon microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Zhuo, Shuangmu, E-mail: shuangmuzhuo@gmail.com, E-mail: hanry-yu@nuhs.edu.sg [Biosystems and Micromechanics IRG, Singapore-MIT Alliance for Research and Technology, 1 CREATE Way, #04-13/14 Enterprise Wing, 138602 Singapore (Singapore); Institute of Laser and Optoelectronics Technology, Fujian Normal University, Fuzhou 350007 (China); Yan, Jie [Biosystems and Micromechanics IRG, Singapore-MIT Alliance for Research and Technology, 1 CREATE Way, #04-13/14 Enterprise Wing, 138602 Singapore (Singapore); Institute of Bioengineering and Nanotechnology, 31 Biopolis Way, #04-01, 138669 Singapore (Singapore); Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, 14 Medical Drive, MD 11 #04-01A, 117599 Singapore (Singapore); Kang, Yuzhan [Biosystems and Micromechanics IRG, Singapore-MIT Alliance for Research and Technology, 1 CREATE Way, #04-13/14 Enterprise Wing, 138602 Singapore (Singapore); Xu, Shuoyu [Biosystems and Micromechanics IRG, Singapore-MIT Alliance for Research and Technology, 1 CREATE Way, #04-13/14 Enterprise Wing, 138602 Singapore (Singapore); Institute of Bioengineering and Nanotechnology, 31 Biopolis Way, #04-01, 138669 Singapore (Singapore); Computation and System Biology Program, Singapore-MIT Alliance, 4 Engineering Drive 3, E4-04-10, 117576 Singapore (Singapore); Peng, Qiwen [Institute of Bioengineering and Nanotechnology, 31 Biopolis Way, #04-01, 138669 Singapore (Singapore); Computation and System Biology Program, Singapore-MIT Alliance, 4 Engineering Drive 3, E4-04-10, 117576 Singapore (Singapore); Mechanobiology Institute, 5A Engineering Drive 1, T-Lab #05-01, 117411 Singapore (Singapore); and others

    2014-07-14

    Various structural features on the liver surface reflect functional changes in the liver. The visualization of these surface features with molecular specificity is of particular relevance to understanding the physiology and diseases of the liver. Using multi-photon microscopy (MPM), we have developed a label-free, three-dimensional quantitative and sensitive method to visualize various structural features of liver surface in living rat. MPM could quantitatively image the microstructural features of liver surface with respect to the sinuosity of collagen fiber, the elastic fiber structure, the ratio between elastin and collagen, collagen content, and the metabolic state of the hepatocytes that are correlative with the pathophysiologically induced changes in the regions of interest. This study highlights the potential of this technique as a useful tool for pathophysiological studies and possible diagnosis of the liver diseases with further development.

  14. Collagen biosynthesis.

    OpenAIRE

    Last, J A; Reiser, K M

    1984-01-01

    Collagen is the major structural protein of the lung. At least five genetically distinct collagen types have been identified in lung tissue. However, the precise role of collagen in nonrespiratory lung function is not well understood, in part because of the difficulties inherent in studying lung collagen, regardless of the type of assay used. A major problem is the insolubility of lung collagen; generally less than 20% of total lung collagen can be solubilized as intact chains, even with hars...

  15. Numerical simulation of three-dimensional boattail afterbody flow fields

    Science.gov (United States)

    Deiwert, G. S.

    1980-01-01

    The thin shear layer approximations of the three-dimensional, compressible Navier-Stokes equations are solved for subsonic, transonic, and supersonic flow over axisymmetric boattail bodies at moderate angles of attack. The plume is modeled by a solid body configuration identical to those used in experimental tests. An implicit algorithm of second-order accuracy is used to solve the equations on the ILLIAC IV computer. The turbulence is expressed by an algebraic model applicable to three-dimensional flow fields with moderate separation. The computed results compare favorably with three different sets of experimental data reported by Reubush, Shrewsbury, and Benek, respectively

  16. Implementation of three dimensional treatment planning system for external radiotherapy

    International Nuclear Information System (INIS)

    A three dimensional (3D) treatment planning system was installed at Apollo Cancer Hospital, Chennai, India in 1995. This paper gives a short description of the system including hardware components, calculation algorithm, measured data requirements and specific three dimensional features. The concept and the structure of the system are shortly described. The first impressions along with critical opinions and the experiences are gained during the data acquisition are mentioned. Some improvements in the user interface are suggested. It is emphasized that although a 3D system offers more detailed and accurate dose distributions compared to a 2D system, it also introduces a greatly increased workload for the planning staff. (author)

  17. Three-dimensional boron particle loaded thermal neutron detector

    Science.gov (United States)

    Nikolic, Rebecca J.; Conway, Adam M.; Graff, Robert T.; Kuntz, Joshua D.; Reinhardt, Catherine; Voss, Lars F.; Cheung, Chin Li; Heineck, Daniel

    2014-09-09

    Three-dimensional boron particle loaded thermal neutron detectors utilize neutron sensitive conversion materials in the form of nano-powders and micro-sized particles, as opposed to thin films, suspensions, paraffin, etc. More specifically, methods to infiltrate, intersperse and embed the neutron nano-powders to form two-dimensional and/or three-dimensional charge sensitive platforms are specified. The use of nano-powders enables conformal contact with the entire charge-collecting structure regardless of its shape or configuration.

  18. Boundary Integral Solutions to Three-Dimensional Unconfined Darcy's Flow

    Science.gov (United States)

    Lennon, Gerard P.; Liu, Philip L.-F.; Liggett, James A.

    1980-08-01

    The boundary integral equation method (BIEM) is used to solve three-dimensional potential flow problems in porous media. The problems considered here are time dependent and have a nonlinear boundary condition on the free surface. The entire boundary, including the moving free surface, discretized into linear finite elements for the purpose of evaluating the boundary integrals. The technique allows transient, three-dimensional problems to be solved with reasonable computational costs. Numerical examples include recharge through rectangular and circular areas and seepage flow from a surface pond. The examples are used to illustrate the method and show the nonlinear effects.

  19. Symmetries and defects in three-dimensional topological field theory

    CERN Document Server

    Fuchs, Jurgen

    2015-01-01

    Boundary conditions and defects of any codimension are natural parts of any quantum field theory. Surface defects in three-dimensional topological field theories of Turaev-Reshetikhin type have applications to two-dimensional conformal field theories, in solid state physics and in quantum computing. We explain an obstruction to the existence of surface defects that takes values in a Witt group. We then turn to surface defects in Dijkgraaf-Witten theories and their construction in terms of relative bundles; this allows one to exhibit Brauer-Picard groups as symmetry groups of three-dimensional topological field theories.

  20. Three-dimensional microtomographic imaging of human brain cortex

    CERN Document Server

    Mizutania, Ryuta; Uesugi, Kentaro; Ohyama, Masami; Takekoshi, Susumu; Osamura, R Yoshiyuki; Suzuki, Yoshio

    2016-01-01

    This paper describes an x-ray microtomographic technique for imaging the three-dimensional structure of the human cerebral cortex. Neurons in the brain constitute a neural circuit as a three-dimensional network. The brain tissue is composed of light elements that give little contrast in a hard x-ray transmission image. The contrast was enhanced by staining neural cells with metal compounds. The obtained structure revealed the microarchitecture of the gray and white matter regions of the frontal cortex, which is responsible for the higher brain functions.

  1. Bootstrapping Critical Ising Model on Three Dimensional Real Projective Space

    Science.gov (United States)

    Nakayama, Yu

    2016-04-01

    Given conformal data on a flat Euclidean space, we use crosscap conformal bootstrap equations to numerically solve the Lee-Yang model as well as the critical Ising model on a three dimensional real projective space. We check the rapid convergence of our bootstrap program in two dimensions from the exact solutions available. Based on the comparison, we estimate that our systematic error on the numerically solved one-point functions of the critical Ising model on a three dimensional real projective space is less than 1%. Our method opens up a novel way to solve conformal field theories on nontrivial geometries.

  2. Three-dimensional theory of the magneto-optical trap

    International Nuclear Information System (INIS)

    The kinetics of atoms in a three-dimensional magneto-optical trap (MOT) is considered. A three-dimensional MOT model has been constructed for an atom with the optical transition Jg = 0 → Je = 1 (Jg, e is the total angular momentum in the ground and excited states) in the semiclassical approximation by taking into account the influence of the relative phases of light fields on the kinetics of atoms. We show that the influence of the relative phases can be neglected only in the limit of low light field intensities. Generally, the choice of relative phases can have a strong influence on the kinetics of atoms in a MOT

  3. Gas-Kinetic BGK Scheme for Three Dimensional Magnetohydrodynamics

    Institute of Scientific and Technical Information of China (English)

    Huazhong

    2010-01-01

    The gas-kinetic theory based flux splitting method has been successfully proposed for solving one- and two-dimensional ideal magnetohydrodynamics by Xu et al.[J. Comput. Phys., 1999; 2000], respectively. This paper extends the kinetic method to solve three-dimensional ideal magnetohydrodynamics equations, where an adaptive parameter η is used to control the numerical dissipation in the flux splitting method.Several numerical examples are given to demonstrate that the proposed method can achieve high numerical accuracy and resolve strong discontinuous waves in three dimensional ideal MHD problems.

  4. Three-dimensional flow and turbulence structure in electrostatic precipitator

    DEFF Research Database (Denmark)

    Ullum, Thorvald Uhrskov; Larsen, Poul Scheel; Özcan, Oktay

    2002-01-01

    Stereo PIV is employed to study the three-dimensional velocity and turbulence fields in a laboratory model of a negative corona, barbed-wire, smooth-plate, electrostatic precipitator (figure 1). The study is focused on determining the parametric effects of axial development, mean current density Jm...... and bulk velocity U0 on secondary flows and turbulence levels and structures due to the action of the three-dimensional electrostatic field on the charged gas. At constant bulk velocity (U0 = 1 m/s) and current density (Jm = 0.4 mA/m2), secondary flows in the form of rolls of axial vorticity with...

  5. Three-dimensional Gd-DTPA MR angiography of cerebral blood vessels

    International Nuclear Information System (INIS)

    Subtraction angiography based on three-dimensional fast MR imaging techniques using rephasing and dephasing gradient pulses is widely used. Similar angiograms can be obtained with three-dimensional gradient techniques before and after the administration of Gd-DTPA followed by imaging subtraction. As Gd-DTPA does not penetrate the blood-brain barrier, it does not alter brain images. Measurements were carried out in 14 patients with a 1.0-T whole-body imager (Siemens, Magnetom). Gd-DTPA angiography was superior to rephased-dephased angiography because of the higher signal intensity, lower noise due to short echo times, and high contrast for moving spins caused by Gd-DTPA

  6. Apparent height and body mass index influence perceived leadership ability in three-dimensional faces.

    Science.gov (United States)

    Re, Daniel E; Dzhelyova, Milena; Holzleitner, Iris J; Tigue, Cara C; Feinberg, David R; Perrett, David I

    2012-01-01

    Facial appearance has a well-documented effect on perceived leadership ability. Face judgments of leadership ability predict political election outcomes across the world, and similar judgments of business CEOs predict company profits. Body height is also associated with leadership ability, with taller people attaining positions of leadership more than their shorter counterparts in both politics and in the corporate world. Previous studies have found some face characteristics that are associated with leadership judgments, however there have been no studies with three-dimensional faces. We assessed which facial characteristics drive leadership judgments in three-dimensional faces. We found a perceptual relationship between height and leadership ability. We also found that facial maturity correlated with leadership judgments, and that faces of people with an unhealthily high body mass index received lower leadership ratings. We conclude that face attributes associated with body size and maturity alter leadership perception, and may influence real-world democratic leadership selection. PMID:23586287

  7. Three-dimensional magnetic analysis of thin films. Development of a three-dimensional micro XMCD technique

    International Nuclear Information System (INIS)

    A three-dimensional micro-X-ray magnetic circular dichroism (XMCD) technique has been developed by combining X-ray microbeams with depth-resolved XMCD. A lateral resolution of several micrometers and a sub-nanometer depth resolution have simultaneously been achieved for ultrathin magnetic films. Preliminary results are given for three-dimensional spin and orbital moment analyses during the spin reorientation transition of Fe/Ni/Cu (100) films, after a brief introduction to the principles underlying the technique. (author)

  8. [Research progress of three-dimensional laparoscope system].

    Science.gov (United States)

    Zhao, Dachuan; Huang, Zonghai; Zou, Zhaowei

    2014-04-01

    The lack of depth perception and spatial orientation in two-dimensional image of traditional laparoscopy require long-term training of the surgeons. Three-dimensional (3D) laparoscopy provides stereoscopic visions as compared to monocular views in a traditional laparoscopic system. In this review, the authors summarize the clinical application of 3D laparoscopy and its current research progress. PMID:24752118

  9. Three-Dimensional Orientation Mapping in the Transmission Electron Microscope

    DEFF Research Database (Denmark)

    Liu, Haihua; Schmidt, Søren; Poulsen, Henning Friis;

    2011-01-01

    Over the past decade, efforts have been made to develop nondestructive techniques for three-dimensional (3D) grain-orientation mapping in crystalline materials. 3D x-ray diffraction microscopy and differential-aperture x-ray microscopy can now be used to generate 3D orientation maps with a spatial...

  10. THE THREE DIMENSIONAL MODELS AND THEIR IDENTIFICATION MINING SUBSIDENCE

    Institute of Scientific and Technical Information of China (English)

    WUGe; SHENGuanghan; JIXiaoming; WANGQuanke

    1995-01-01

    The theory and method for selecting the three dimensional prediction models of mining subsidence are studied in this paper. Namely, based on system identification and statistics theory, an optimum mining subsidence prediction model can be selected. The method proved by a typical case has a good prospect for determining the physical model of rock mass for mining subsidence prediction.

  11. Approaching the Sequential and Three-Dimensional Organization of Genomes

    NARCIS (Netherlands)

    T.A. Knoch (Tobias)

    2006-01-01

    textabstractGenomes are one of the major foundations of life due to their role in information storage, process regulation and evolution. To achieve a deeper unterstanding of the human genome the three-dimensional organization of the human cell nucleus, the structural-, scaling- and dynamic prope

  12. First experimental results on new microstrip three dimensional geometry

    International Nuclear Information System (INIS)

    A new type of three-dimensional microstrip gas counter (MHSC stands for micro-heightened strips counter) has been built using deep X-ray lithography at LURE. The first measurements show that this new proportional counter has a very stable gain and is able to support high counting rates. ((orig.))

  13. Thermodynamics of a Simple Three-Dimensional DNA Hairpin Model

    CERN Document Server

    Kremer, Kellan; Boggess, Erin; Mask, Walker; Saucedo, Tony; Hansen, JJ; Appelgate, Ian; Jurgensen, Taylor; Santos, Aaron

    2016-01-01

    We characterize the equation of state for a simple three-dimensional DNA hairpin model using a Metropolis Monte Carlo algorithm. This algorithm was run at constant temperature and fixed separation between the terminal ends of the strand. From the equation of state, we compute the compressibility, thermal expansion coefficient, and specific heat along with adiabatic path.

  14. Three-dimensional organization of electrical turbulence in the heart

    NARCIS (Netherlands)

    Panfilov, A.V.

    2002-01-01

    Three-dimensional organization of electrical turbulence that is induced via the phenomenon of spiral breakup is studied in a computer model of the heart, which includes realistic ventricular geometries and cardiac anisotropy. We find filaments of rotors during the turbulence and study their number a

  15. A Novel Three-Dimensional Tool for Teaching Human Neuroanatomy

    Science.gov (United States)

    Estevez, Maureen E.; Lindgren, Kristen A.; Bergethon, Peter R.

    2010-01-01

    Three-dimensional (3D) visualization of neuroanatomy can be challenging for medical students. This knowledge is essential in order for students to correlate cross-sectional neuroanatomy and whole brain specimens within neuroscience curricula and to interpret clinical and radiological information as clinicians or researchers. This study implemented…

  16. Three-Dimensional Evolution of the Galactic Fountain

    CERN Document Server

    D'Avillez, M A

    1999-01-01

    Gas that escapes from the Galactic disk, rises into the halo, cools and falls back, constitutes a "Galactic Fountain". Three-Dimensional simulations show that such a fountain model reproduces many of the features that have been observed in the Galaxy and other galaxies such as M31 and M33. Here, these results are reported.

  17. Three Dimensional Charged Black Hole Inspired by Noncommutative Geometry

    CERN Document Server

    Larranaga, Alexis

    2010-01-01

    We find a new charged black hole in three-dimensional anti-de Sitter space using an anisotropic perfect fluid inspired by the noncommutative black hole as the source of matter and a gaussian distribution of electric charge. We deduce the thermodynamical quantities of this black hole and compare them with those of a charged BTZ solution.

  18. Three-dimensional image reconstruction for scattering light tomography

    International Nuclear Information System (INIS)

    For optical imaging of testes we have developed three-dimensional image reconstruction algorithms for scattering light tomography in the near-infrared range. The mathematical problem is thereby decomposed into a pixel conversion step and an inverse problem solver. Different voxal bases and solution methods have been selected and evaluated. (author)

  19. Three-Dimensional Extension of a Digital Library Service System

    Science.gov (United States)

    Xiao, Long

    2010-01-01

    Purpose: The paper aims to provide an overall methodology and case study for the innovation and extension of a digital library, especially the service system. Design/methodology/approach: Based on the three-dimensional structure theory of the information service industry, this paper combines a comprehensive analysis with the practical experiences…

  20. Three-dimensional organization of the human interphase nucleus

    NARCIS (Netherlands)

    T.A. Knoch (Tobias); C. Münkel (Christian); W. Waldeck (Waldemar); J. Langowski (Jörg)

    2000-01-01

    textabstractDespite the successful linear sequencing of the human genome its three-dimensional structure is widely unknown, although it is important for gene regulation and replication. For a long time the interphase nucleus has been viewed as a 'spaghetti soup' of DNA without much internal structur

  1. Generation of a Desired Three-Dimensional Electromagnetic Field

    DEFF Research Database (Denmark)

    2005-01-01

    The present invention relates to a method and a system for synthesizing a prescribed three-dimensional electromagnetic field based on generalized phase contrast imaging. Such a method and apparatus may be utilized in advanced optical micro and nano-manipulation, such as by provision of a multiple...

  2. Algebraic Ricci Solitons of three-dimensional Lorentzian Lie groups

    CERN Document Server

    Batat, Wafaa

    2011-01-01

    We classify Algebraic Ricci Solitons of three-dimensional Lorentzian Lie groups. All algebraic Ricci solitons that we obtain are sol-solitons. In particular, we prove that, contrary to the Riemannian case, Lorentzian Ricci solitons need not to be algebraic Ricci solitons.

  3. Quantum field between moving mirrors: A three dimensional example

    Science.gov (United States)

    Hacyan, S.; Jauregui, Roco; Villarreal, Carlos

    1995-01-01

    The scalar quantum field uniformly moving plates in three dimensional space is studied. Field equations for Dirichlet boundary conditions are solved exactly. Comparison of the resulting wavefunctions with their instantaneous static counterpart is performed via Bogolubov coefficients. Unlike the one dimensional problem, 'particle' creation as well as squeezing may occur. The time dependent Casimir energy is also evaluated.

  4. Three-dimensional reconstruction of the otosclerotic focus

    DEFF Research Database (Denmark)

    Bloch, Sune Land; Sørensen, Mads Sølvsten

    2010-01-01

    The location and three-dimensional (3D) shapes of the otosclerotic foci suggest a general centripetal distribution of otosclerotic bone remodeling around the inner ear space, whereas the normal bone remodeling is distributed centrifugally. The existence of an inverse spatial relation between norm...

  5. Spurious solutions of three-dimensional Faddeev equations

    International Nuclear Information System (INIS)

    The spurious solutions of the three-dimensional Faddeev equations, written in the representation of total angular momentum and total spatial parity, are derived explicitly. It is shown how one can use the spurious solutions as standard ones in testing the numerical algorithms for solving these equations

  6. Modeling snow crystal growth III: three-dimensional snowfakes

    OpenAIRE

    Gravner, Janko; Griffeath, David

    2007-01-01

    We introduce a three-dimensional, computationally feasible, mesoscopic model for snow crystal growth, based on diffusion of vapor, anisotropic attachment, and a semi-liquid boundary layer. Several case studies are presented that faithfully emulate a wide variety of physical snowflakes.

  7. Three-dimensional container and cargo inspection system

    Science.gov (United States)

    Tumer, Tumay O.; Su, Chih-Wu; Baritelle, J.; Rhoton, B.

    1997-02-01

    A fusion of two independent but complementary three- dimensional imaging techniques is proposed for detecting drugs in containers, cargo, mail and luggage. The containers, cargo, mail and/or luggage are scanned using a combined neutron and gamma ray source. A detector that can detect both neutrons and gamma rays is used to produce three dimensional images from both signals. The two images will be combined and analyzed by a fast host computer to detect drugs that may be concealed in the container, cargo and/or luggage. The two independent signatures from both neutrons and gamma rays, when analyzed simultaneously, may help determine the type of concealed material inside the containers. Containers, cargo and luggage are filled with a large variety of materials. Imaging them only in two dimensions may result in a poor contraband detection probability as different materials may shield each other. Therefore, a true three-dimensional imaging system is proposed, where the individual items inside the container or cargo can be resolved. This is expected to lead to reliable identification of the drugs even in small quantities. Such a system will also pinpoint the location of the suspected item and help expedite inspection by law enforcement agents. The proposed detection system produces two complementary three- dimensional images of the containers, cargo and/or luggage. These images are combined and analyzed by a specially developed algorithm to identify and locate the contraband automatically.

  8. A Three-Dimensional Haptic Matrix Test of Nonverbal Reasoning

    Science.gov (United States)

    Miller, Joseph C.; Skillman, Gemma D.; Benedetto, Joanne M.; Holtz, Ann M.; Nassif, Carrie L.; Weber, Anh D.

    2007-01-01

    Three-dimensional haptic matrices were pilot-tested as a nonvisual measure of cognitive ability. The results indicated that they correlated with convergent measures, with emphasis on spatial processing and that the participants who described items "visually" completed them more quickly and accurately and tended to have become visually impaired…

  9. Three-dimensional radiometric aperture synthesis microscopy for security screening

    Science.gov (United States)

    Salmon, Neil A.; Bowring, Nick

    2014-10-01

    The three dimensional (3D) aperture synthesis imaging technique investigated here is a generalisation of the classic twodimensional radio astronomy technique with refinements for the near-field so it can be applied a personnel security screening portal. This technique can be viewed as a novel form of diffraction emission tomography and extends previous 3D aperture synthesis imaging research using matrix inversion techniques [1]. Simulations using three-dimensional Fourier transforms to create three-dimensional images from simulated three-dimensional visibility functions illustrate the Abbe microscopy resolution should be achievable in three dimensions simultaneously in a single sensor. The field-of-view is demonstrated to be limited by Fresnel scale effects and a means to over coming this by processing sub-sets of local visibility functions with different phase centres throughout the imaging volume is presented. The applications of this technique to a full 3D imaging security screening portal is explored and a route to extending simulation software for market driven imaging scenarios is discussed.

  10. Green function of a three-dimensional Wick problem

    International Nuclear Information System (INIS)

    An exact solution of a three-dimensional Coulomb Wick-Cutkovsky problem has been obtained which possesses the hidden 0(4)-symmetry. Here we shell give the derivation of the corresponding Green function and consider its connection with the asymptoric behaviour of the scattering amplitude. 9 refs

  11. Three-dimensional imaging with a terahertz quantum cascade laser

    OpenAIRE

    Nguyen, K. L.; Johns, M. L.; L F Gladden; Worrall, C. H.; Alexander, P.; Beere, H.E.; Pepper, M.; Ritchie, D. A.; Alton, J.; Barbieri, S; Linfield, E.H.

    2006-01-01

    Results are presented for the first imaging system that combines the high power of terahertz quantum cascade lasers with three- dimensional image reconstruction based on filtered back- projection. Images of various phantoms have been successfully reconstructed revealing both their external and internal structures. (c) 2006 Optical Society of America.

  12. Three-dimensional holographic display of images of otological specimens.

    Science.gov (United States)

    Ogura, Y; Masuda, Y; Takeda, T; Kawakami, S; Ishihara, M; Tsujiuchi, J; Suzuki, M; Saito, T; Kawasaki, C

    1983-01-01

    Three-dimensional displays of anatomical structures and clinical findings are very persuasive and instructive. Using multiplex holograms, we designed a display of three-dimensional images of otological specimens. Multiplex holograms, reported by Cross of the United States in 1975, enable reconstruction of three-dimensional moving images and are used for artistic display as well as for teaching in medicine and general education. Multiplex holograms were recorded in a two-step process. The first step is to make a series of original cine-pictures of an object from different horizontal directions, rotating it on a turntable. In the second step, one frame of the original film is recorded on a narrow strip hologram. All frames of the original film are recorded one after another and a complete multiplex hologram can be synthesized. In the reconstruction stage, the multiplex hologram is formed into a cylinder and illuminated from below by a small white light source. Reconstructions of the three-dimensional bright images of the object inside the cylindrical holographic screen are shown. PMID:6670959

  13. Three-dimensional display of nuclear images using multiplex holography

    International Nuclear Information System (INIS)

    Using multiplex holography (MH), we tried to show a three-dimensional display of nuclear images. There were no level-down of resolution when composed to hologram. A clinical problem, existed in which some images had distortion at their edges. We examined the resolution using a SPECT phantom. In MH by planar image, both legions (hot and cold) were 17.9 mm diameter, in MH by RCT data and three-dimensional display on the CRT, both legions were 22.4 mm diameter. Three-dimensional display by MH using planar image takes a long time for data collection, but there was no level-down of resolution. We used digital filters for further improvement of the quality of the original image. Band pass and Wiener filters are available, but I think it is necessary to develop the most suitable filter for each internal organ. In the results, three-dimensional display by MH is the most available method regarding education and clinical medicine. (author)

  14. Three-dimensional reconstruction of the otosclerotic focus

    DEFF Research Database (Denmark)

    Bloch, Sune Land; Sørensen, Mads Sølvsten

    2010-01-01

    The location and three-dimensional (3D) shapes of the otosclerotic foci suggest a general centripetal distribution of otosclerotic bone remodeling around the inner ear space, whereas the normal bone remodeling is distributed centrifugally. The existence of an inverse spatial relation between normal...

  15. Three-dimensional simulations of free-electron laser physics

    International Nuclear Information System (INIS)

    A computer code has been developed to simulate three-dimensional free-electron laser physics. A mathematical formulation of the FEL equations is presented, and the numerical solution of the problem is described. Sample results from the computer code are discussed. 23 refs., 6 figs., 2 tabs

  16. Holographic positive energy theorems in three-dimensional gravity

    OpenAIRE

    Barnich, Glenn; Oblak, Blagoje

    2014-01-01

    The covariant phase space of three-dimensional asymptotically flat and anti-de Sitter gravity is controlled by well-understood coadjoint orbits of the Virasoro group. Detailed knowledge on the behavior of the energy functional on these orbits can be used to discuss positive energy theorems.

  17. Generators of quasiperiodic oscillations with three-dimensional phase space

    DEFF Research Database (Denmark)

    Kuznetsov, A.P.; Kuznetsov, S.P.; Mosekilde, Erik;

    2013-01-01

    Considering a family of three-dimensional oscillators originating in the field of radio-engineering, the paper describes three different mechanisms of torus formation. Particular emphasis is paid to a process in which a saddle-node bifurcation eliminates a stable cycle and leaves the system to fi...

  18. Polycrystalline diamond detectors with three-dimensional electrodes

    Energy Technology Data Exchange (ETDEWEB)

    Lagomarsino, S., E-mail: lagomarsino@fi.infn.it [University of Florence, Department of Physics, Via Sansone 1, 50019 Sesto Fiorentino (Italy); INFN Firenze, Via B. Rossi 1, 50019 Sesto Fiorentino (Italy); Bellini, M. [INO-CNR Firenze, Largo E. Fermi 6, 50125 Firenze (Italy); Brianzi, M. [INFN Firenze, Via B. Rossi 1, 50019 Sesto Fiorentino (Italy); Carzino, R. [Smart Materials-Nanophysics, Istituto Italiano di Tecnologia, Genova, Via Morego 30, 16163 Genova (Italy); Cindro, V. [Joseph Stefan Institute, Jamova Cesta 39, 1000 Ljubljana (Slovenia); Corsi, C. [University of Florence, Department of Physics, Via Sansone 1, 50019 Sesto Fiorentino (Italy); LENS Firenze, Via N. Carrara 1, 50019 Sesto Fiorentino (Italy); Morozzi, A.; Passeri, D. [INFN Perugia, Perugia (Italy); Università degli Studi di Perugia, Dipartimento di Ingegneria, via G. Duranti 93, 06125 Perugia (Italy); Sciortino, S. [University of Florence, Department of Physics, Via Sansone 1, 50019 Sesto Fiorentino (Italy); INFN Firenze, Via B. Rossi 1, 50019 Sesto Fiorentino (Italy); Servoli, L. [INFN Perugia, Perugia (Italy)

    2015-10-01

    The three-dimensional concept in diamond detectors has been applied, so far, to high quality single-crystal material, in order to test this technology in the best available conditions. However, its application to polycrystalline chemical vapor deposited diamond could be desirable for two reasons: first, the short inter-electrode distance of three-dimensional detectors should improve the intrinsically lower collection efficiency of polycrystalline diamond, and second, at high levels of radiation damage the performances of the poly-crystal material are not expected to be much lower than those of the single crystal one. We report on the fabrication and test of three-dimensional polycrystalline diamond detectors with several inter-electrode distances, and we demonstrate that their collection efficiency is equal or higher than that obtained with conventional planar detectors fabricated with the same material. - Highlights: • Pulsed laser fabrication of polycristalline diamond detectors with 3D electrodes. • Measurement of the charge collection efficiency (CCE) under beta irradiation. • Comparation between the CCE of 3D and conventional planar diamond sensors. • A rationale for the behavior of three-dimensional and planar sensors is given.

  19. Flux penetrations into two- and three-dimensional nanostructured superconductors

    International Nuclear Information System (INIS)

    Highlights: • Flux penetrations into two- and three-dimensional nanostructured superconductors are observed by magneto-optical imaging. • In two-dimensional superconducting networks with square holes on square lattice, anomalous diagonal penetrations are observed. • In three-dimensional superconducting shifted strip arrays, various forms of vortex avalanches are observed. - Abstract: We have fabricated two- and three-dimensional nanostructured superconductors, and observed vortex penetrations by magneto-optical imaging. In the case of two-dimensional superconducting networks with square holes on a square lattice, anomalous diagonal penetrations are widely observed. Two kinds of diagonal vortex penetrations at high and low temperatures have been interpreted as originating from the repulsive interaction of vortices and sharp fan-shaped vortex penetration from the corners of the square holes, respectively. In the case of three-dimensional stack of superconducting strip arrays with double and triple layers, vortex avalanches have been observed in a wide temperature and dimension ranges due to enhanced demagnetization effect. While spotlike avalanches are observed when the overlap of strips is small, anomalous linear avalanches traversing many strips in different layers are observed when the overlap is large. In triple-layer strip arrays, in addition to the spotlike and linear avalanches, vortex penetrations along the line of strips are also observed. Origins of the anomalous diagonal penetration and vortex avalanches are discussed

  20. A deterministic method for transient, three-dimensional neutron transport

    International Nuclear Information System (INIS)

    A deterministic method for solving the time-dependent, three-dimensional Boltzmann transport equation with explicit representation of delayed neutrons has been developed and evaluated. The methodology used in this study for the time variable of the neutron flux is known as the improved quasi-static (IQS) method. The position, energy, and angle-dependent neutron flux is computed deterministically by using the three-dimensional discrete ordinates code TORT. This paper briefly describes the methodology and selected results. The code developed at the University of Tennessee based on this methodology is called TDTORT. TDTORT can be used to model transients involving voided and/or strongly absorbing regions that require transport theory for accuracy. This code can also be used to model either small high-leakage systems, such as space reactors, or asymmetric control rod movements. TDTORT can model step, ramp, step followed by another step, and step followed by ramp type perturbations. It can also model columnwise rod movement. A special case of columnwise rod movement in a three-dimensional model of a boiling water reactor (BWR) with simple adiabatic feedback is also included. TDTORT is verified through several transient one-dimensional, two-dimensional, and three-dimensional benchmark problems. The results show that the transport methodology and corresponding code developed in this work have sufficient accuracy and speed for computing the dynamic behavior of complex multi-dimensional neutronic systems

  1. A DETERMINISTIC METHOD FOR TRANSIENT, THREE-DIMENSIONAL NUETRON TRANSPORT

    International Nuclear Information System (INIS)

    A deterministic method for solving the time-dependent, three-dimensional Boltzmam transport equation with explicit representation of delayed neutrons has been developed and evaluated. The methodology used in this study for the time variable of the neutron flux is known as the improved quasi-static (IQS) method. The position, energy, and angle-dependent neutron flux is computed deterministically by using the three-dimensional discrete ordinates code TORT. This paper briefly describes the methodology and selected results. The code developed at the University of Tennessee based on this methodology is called TDTORT. TDTORT can be used to model transients involving voided and/or strongly absorbing regions that require transport theory for accuracy. This code can also be used to model either small high-leakage systems, such as space reactors, or asymmetric control rod movements. TDTORT can model step, ramp, step followed by another step, and step followed by ramp type perturbations. It can also model columnwise rod movement can also be modeled. A special case of columnwise rod movement in a three-dimensional model of a boiling water reactor (BWR) with simple adiabatic feedback is also included. TDTORT is verified through several transient one-dimensional, two-dimensional, and three-dimensional benchmark problems. The results show that the transport methodology and corresponding code developed in this work have sufficient accuracy and speed for computing the dynamic behavior of complex multidimensional neutronic systems

  2. Nonaffine behavior of three-dimensional semiflexible polymer networks

    Science.gov (United States)

    Hatami-Marbini, Hamed

    2016-04-01

    Three-dimensional semiflexible polymer networks are the structural building blocks of various biological and structural materials. Previous studies have primarily used two-dimensional models for understanding the behavior of these networks. In this paper, we develop a three-dimensional nonaffinity measure capable of providing direct comparison with continuum level homogenized quantities, i.e., strain field. The proposed nonaffinity measure is capable of capturing possible anisotropic microstructures of the filamentous networks. This strain-based nonaffinity measure is used to probe the mechanical behavior at different length scales and investigate the effects of network mechanical and microstructural properties. Specifically, it is found that although all nonaffinity measure components have a power-law variation with the probing length scale, the degree of nonaffinity decreases with increasing the length scale of observation. Furthermore, the amount of nonaffinity is a function of network fiber density, bending stiffness of the constituent filaments, and the network architecture. Finally, it is found that the two power-law scaling regimes previously reported for two-dimensional systems do not appear in three-dimensional networks. Also, unlike two-dimensional models, the exponent of the power-law relation depends weakly on the density of the three-dimensional networks.

  3. Scattering and conductance quantization in three-dimensional metal nanocontacts

    DEFF Research Database (Denmark)

    Brandbyge, Mads; Jacobsen, Karsten Wedel; Nørskov, Jens Kehlet

    1997-01-01

    The transmission through three-dimensional nanocontacts is calculated in the presence of localized scattering centers and boundary scattering using a coupled-channel recursion method. Simple confining potentials are used to investigate how robust the observation of quantized conductance is with r...

  4. Three-Dimensional Printing Using a Photoinitiated Polymer

    Science.gov (United States)

    Muskin, Joseph; Ragusa, Matthew; Gelsthorpe, Thomas

    2010-01-01

    Printers capable of producing three-dimensional objects are becoming more common. Most of these printers are impractical for use in the chemistry classroom because of the expense incurred in fabricating a print head that must be controlled in three dimensions. We propose a simpler solution to this problem that allows the emerging technology of…

  5. Oblique water entry of a three dimensional body

    Directory of Open Access Journals (Sweden)

    Scolan Yves-Marie

    2014-12-01

    Full Text Available The problem of the oblique water entry of a three dimensional body is considered. Wagner theory is the theoretical framework. Applications are discussed for an elliptic paraboloid entering an initially flat free surface. A dedicated experimental campaign yields a data base for comparisons. In the present analysis, pressure, force and dynamics of the wetted surface expansion are assessed.

  6. Three dimensional reconstruction of tomographic images of the retina

    International Nuclear Information System (INIS)

    The development of a new display system for the three-dimensional visualization of tomographic images in ophthalmology. Specifically, a system that can use stacks of B-mode scans from an ultrahigh resolution optical tomography examination to vividly display retinal specimens as three-dimensional objects. Several subroutines were programmed in the rendering and raytracing program Cinema 4D XL 9.102 Studio Bundle (Maxon Computer Inc., Friedrichsburg, Germany), which could process stacks of tomographic scans into three-dimensional objects. Ultrahigh resolution optical coherence tomography examinations were performed on patients with various retinal pathologies and post processed with the subroutines that had been designed. All ultrahigh resolution optical coherence tomographies were performed with a titanium: sapphire based ultra broad bandwidth (160 nm) femtosecond laser system (INTEGRAL, Femtolasers Productions GmbH. Vienna Austria) with an axial resolution of 3 μm. A new three dimensional display system for tomographic images in ophthalmology was developed, which allows a highly vivid display of physiological and pathological structures of the retina. The system also distinguishes itself through its high interactivity and adaptability. This new display system allows the visualization of physiological and pathological structures of the retina in a new way, which will give us new insight into their morphology and development. (author)

  7. Signal analysis of three-dimensional nystagmus for otoneurological investigations.

    Science.gov (United States)

    Juhola, Martti; Aalto, Heikki; Jutila, Topi; Hirvonen, Timo P

    2011-03-01

    Three-dimensional signal analysis can be applied to eye movements called nystagmus in order to study otoneurological patients suffering from vertigo and other balance problems. We developed an analysis and modeling algorithm for three-dimensional nystagmus measured by a video-oculography system. We were also interested in verifying an otoneurological hands-on convention called Ewald's first law in a strict physiological sense in vestibular patients. We recorded nystagmus from 42 patients all suffering from vertigo or dizziness. The underlying pathology was unilateral in 39 patients, bilateral in one patient, and central in two patients. Video-oculography was used to record three-dimensional nystagmus to separately produce horizontal, vertical, and torsional signals for each eye. On the basis of signal analysis techniques and straightforward vector calculus, we were able to recognize slow phases of nystagmus to compute their angular velocities to estimate from which part of the inner ear the disorder originated. We found that for all 42 patients the plane of one of the two horizontal semicircular canals was the closest. We were able to quantitatively estimate the influence of different semicircular canals, and, despite the pathology, horizontal canals seemed to be predominant in driving the nystagmus. The signal analysis and modeling algorithm developed is effective in studying otoneurological problems registered with nystagmus and opens new insights in three-dimensional nystagmography. Our results strongly support Ewald's first law. PMID:21107695

  8. Three-dimensional reconstruction of the rat nephron

    DEFF Research Database (Denmark)

    Christensen, Erik Ilsø; Grann, Birgitte; Kristoffersen, Inger B.;

    2014-01-01

    This study gives a three-dimensional (3D) structural analysis of rat nephrons and their connections to collecting ducts. Approximately 4,500 2.5-μm-thick serial sections from the renal surface to the papillary tip were obtained from each of 3 kidneys of Wistar rats. Digital images were recorded and...

  9. Three-dimensional space as a medium of quantum entanglement

    Science.gov (United States)

    Fiscaletti, Davide; Sorli, Amrit S.

    2012-01-01

    Most physicists today still conceptualize time as a part of the physical space in which material objects move, although time has never been observed and measured as a part of the space. The concept of time here presented is that time measured with clocks is merely the numerical order of material change, i.e. motion in a three-dimensional space. In special relativity the Minkowskian four-dimensional space-time can be replaced with a three-dimensional space where time does not represent a fourth coordinate of space but must be considered merely as a mathematical quantity measuring the numerical order of material changes. By quantum entanglement the three-dimensional space is a medium of a direct information transfer between quantum particles. Numerical order of non-local correlations between subatomic particles in EPR-type experiments and other immediate quantum processes is zero in the sense that the three-dimensional space acts as an immediate information medium between them

  10. Three-dimensional organization of the human interphase nucleus

    NARCIS (Netherlands)

    T.A. Knoch (Tobias); M. Wachsmuth (Malte); W. Waldeck (Waldemar); J. Langowski (Jörg)

    2002-01-01

    markdownabstractTo approach the three-dimensional organization of the human cell nucleus, the structural-, scaling- and dynamic properties of interphase chromosomes and cell nuclei were simulated with Monte Carlo and Brownian Dynamics methods. The 30 nm chromatin fibre was folded according to the Mu

  11. Three-dimensional organization of the human interphase nucleus.

    NARCIS (Netherlands)

    T.A. Knoch (Tobias); M. Wachsmuth (Malte); W. Waldeck (Waldemar); J. Langowski (Jörg)

    2002-01-01

    textabstractTo approach the three-dimensional organization of the human cell nucleus, the structural-, scaling- and dynamic properties of interphase chromosomes and cell nuclei were simulated with Monte Carlo and Brownian Dynamics methods. The 30 nm chromatin fibre was folded according to the Multi-

  12. Three-dimensional organization of the human interphase nucleus

    NARCIS (Netherlands)

    T.A. Knoch (Tobias); M. Wachsmuth (Malte); W. Waldeck (Waldemar); J. Langowski (Jörg)

    2002-01-01

    textabstractTo approach the three-dimensional organization of the human cell nucleus, the structural-, scaling- and dynamic properties of interphase chromosomes and cell nuclei were simulated with Monte Carlo and Brownian Dynamics methods. The 30 nm chromatin fibre was folded according to the Mul

  13. From chemical topology to three-dimensional geometry

    CERN Document Server

    Balaban, A T

    1997-01-01

    Researchers who are active and often pioneers in the field explain how to provide mathematically non-sophisticated molecular descriptions encompassing three-dimensional aspects of molecules, which allow an easy intuitive grasp of their significance, the possibility of computing them for any imaginab

  14. Vacuum polarization around a three-dimensional black hole

    CERN Document Server

    Shiraishi, Kiyoshi

    2015-01-01

    We calculate the Euclidean propagator for a conformally coupled massless scalar field in the background of the three-dimensional black hole. The expectation value $\\langle\\varphi^2\\rangle$ in the Hartle-Hawking state is obtained in the spacetime.

  15. Three-Dimensional Modelling inside a Differential Pressure Laminar Flow Bioreactor Filled with Porous Media

    Directory of Open Access Journals (Sweden)

    Birgit Weyand

    2015-01-01

    Full Text Available A three-dimensional computational fluid dynamics- (CFD- model based on a differential pressure laminar flow bioreactor prototype was developed to further examine performance under changing culture conditions. Cell growth inside scaffolds was simulated by decreasing intrinsic permeability values and led to pressure build-up in the upper culture chamber. Pressure release by an integrated bypass system allowed continuation of culture. The specific shape of the bioreactor culture vessel supported a homogenous flow profile and mass flux at the scaffold level at various scaffold permeabilities. Experimental data showed an increase in oxygen concentration measured inside a collagen scaffold seeded with human mesenchymal stem cells when cultured in the perfusion bioreactor after 24 h compared to static culture in a Petri dish (dynamic: 11% O2 versus static: 3% O2. Computational fluid simulation can support design of bioreactor systems for tissue engineering application.

  16. Evaluation of cell binding to collagen and gelatin: a study of the effect of 2D and 3D architecture and surface chemistry.

    Science.gov (United States)

    Davidenko, Natalia; Schuster, Carlos F; Bax, Daniel V; Farndale, Richard W; Hamaia, Samir; Best, Serena M; Cameron, Ruth E

    2016-10-01

    Studies of cell attachment to collagen-based materials often ignore details of the binding mechanisms-be they integrin-mediated or non-specific. In this work, we have used collagen and gelatin-based substrates with different dimensional characteristics (monolayers, thin films and porous scaffolds) in order to establish the influence of composition, crosslinking (using carbodiimide) treatment and 2D or 3D architecture on integrin-mediated cell adhesion. By varying receptor expression, using cells with collagen-binding integrins (HT1080 and C2C12 L3 cell lines, expressing α2β1, and Rugli expressing α1β1) and a parent cell line C2C12 with gelatin-binding receptors (αvβ3 and α5β1), the nature of integrin binding sites was studied in order to explain the bioactivity of different protein formulations. We have shown that alteration of the chemical identity, conformation and availability of free binding motifs (GxOGER and RGD), resulting from addition of gelatin to collagen and crosslinking, have a profound effect on the ability of cells to adhere to these formulations. Carbodiimide crosslinking ablates integrin-dependent cell activity on both two-dimensional and three-dimensional architectures while the three-dimensional scaffold structure also leads to a high level of non-specific interactions remaining on three-dimensional samples even after a rigorous washing regime. This phenomenon, promoted by crosslinking, and attributed to cell entrapment, should be considered in any assessment of the biological activity of three-dimensional substrates. Spreading data confirm the importance of integrin-mediated cell engagement for further cell activity on collagen-based compositions. In this work, we provide a simple, but effective, means of deconvoluting the effects of chemistry and dimensional characteristics of a substrate, on the cell activity of protein-derived materials, which should assist in tailoring their biological properties for specific tissue engineering

  17. Bone marrow-derived mesenchymal stem cells in three-dimensional culture promote neuronal regeneration by neurotrophic protection and immunomodulation.

    Science.gov (United States)

    Han, Sufang; Wang, Bin; Li, Xing; Xiao, Zhifeng; Han, Jin; Zhao, Yannan; Fang, Yongxiang; Yin, Yanyun; Chen, Bing; Dai, Jianwu

    2016-07-01

    Accumulating evidence has revealed three-dimensional (3D) culture could better mimic the stem cell niche in vivo in comparison with conventional two-dimensional (2D) culture. In this study, we found that bone marrow derived mesenchymal stem cells (BMSCs) cultured in 3D collagen scaffold (3D BMSCs) exhibited distinctive features including significantly enhancing neurotrophic factor secretions and reducing macrophage activations challenged by lipopolysaccharide (LPS) in vitro. To further evaluate 3D BMSCs' potential benefits to the regeneration of spinal cord injury (SCI), the 3D and 2D BMSCs were respectively implanted in rat hemisected SCI. Compared with 2D cohort, 3D BMSCs transplantation significantly reduced the expressions of inflammatory cytokines such as TNF-α, IL-1β, and IL-6 at 5 days after transplantation, markedly enhanced axonal regeneration, and promoted motor functional recovery during 8 weeks of observation. When Nocodazole was used to depolymerize the cytoskeleton of 3D BMSCs, the changed expressions of neurotrophic factors and inflammatory cytokines were blunted, at least partially. Thus synergistic effects of neuronal protection and immunomodulation of 3D BMSCs may lead to a better functional recovery of SCI and the underlying mechanism may involve the alteration of their cellular morphology because of 3D culture. This study contributes to a better understanding of the cellular characteristics of 3D BMSCs and provides a novel strategy to promote the repair of the injured spinal cord. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 1759-1769, 2016. PMID:26990583

  18. Construction of collagen scaffolds that mimic the three-dimensional architecture of specific tissues.

    OpenAIRE

    Faraj, K.A.; Kuppevelt, A. H. M. S. M.; Daamen, W.F.

    2007-01-01

    Every tissue and organ has its own 3-dimensional (3D) extracellular matrix (ECM) organization. Cells in a 3D bioscaffold for tissue engineering typically align new ECM components according to the bioscaffold provided. Therefore, scaffolds with a specific 3D structural design resembling the actual ECM of a particular tissue may have great potential in tissue engineering. Here, we show that, using specific freezing regimes, 3D scaffolds that mimic the 3D architecture of specific tissues can be ...

  19. Three-dimensional genome architecture influences partner selection for chromosomal translocations in human disease.

    Directory of Open Access Journals (Sweden)

    Jesse M Engreitz

    Full Text Available Chromosomal translocations are frequent features of cancer genomes that contribute to disease progression. These rearrangements result from formation and illegitimate repair of DNA double-strand breaks (DSBs, a process that requires spatial colocalization of chromosomal breakpoints. The "contact first" hypothesis suggests that translocation partners colocalize in the nuclei of normal cells, prior to rearrangement. It is unclear, however, the extent to which spatial interactions based on three-dimensional genome architecture contribute to chromosomal rearrangements in human disease. Here we intersect Hi-C maps of three-dimensional chromosome conformation with collections of 1,533 chromosomal translocations from cancer and germline genomes. We show that many translocation-prone pairs of regions genome-wide, including the cancer translocation partners BCR-ABL and MYC-IGH, display elevated Hi-C contact frequencies in normal human cells. Considering tissue specificity, we find that translocation breakpoints reported in human hematologic malignancies have higher Hi-C contact frequencies in lymphoid cells than those reported in sarcomas and epithelial tumors. However, translocations from multiple tissue types show significant correlation with Hi-C contact frequencies, suggesting that both tissue-specific and universal features of chromatin structure contribute to chromosomal alterations. Our results demonstrate that three-dimensional genome architecture shapes the landscape of rearrangements directly observed in human disease and establish Hi-C as a key method for dissecting these effects.

  20. Interactive two- and three-dimensional CT imaging of tibial plateau fractures

    International Nuclear Information System (INIS)

    Fifteen patients with known or suspected tibial plateau fractures were examined by means of interactive animated Orthotool two-dimensional CT (transaxial, coronal, and sagittal planes) and animated volumetric three-dimensional imaging performed with the Pixar image computer. Transaxial CT alone is inadequate to characterize the articular tibial plateau, since the structure of interest approximately parallels the plane of scanning. Reformatted interactive coronal and sagittal series allow precise characterization of fracture fragments and articular surface depression or disruption. Documented involvement of the tibial spines alters proposed management but may be subtle on plain films alone. The program used allows easy comparison with the contralateral (normal) tibia to enhance appreciation of subtle pathology. Animated three-dimensional images are edited to remove casts and the contralateral knee and are rotated in two planes. According to the authors, their analysis shows better specific detail on the two-dimensional images, with the three-dimensional images most often being used for final surgical planning and overview

  1. Selective three-dimensional hydrophilization of microstructured polymer surfaces through confined photocatalytic oxidation

    International Nuclear Information System (INIS)

    Graphical abstract: - Highlights: • Microstructured polymer surfaces with selective 3-D anisotropy were created. • Selective UV treatment was performed to alter surface wettability. • Removable meshes resembling a photomask were applied during UV treatment. • Micropatterning by viscous polymer on solid surface was performed. - Abstract: While the conventional photomask technique gives only two-dimensional anisotropies, in this study we fabricated microstructured polymer surfaces with a selective three-dimensional anisotropy. With the applied removable mesh, we were able to confine the contacting area between the surface and photoinitiator and provide three-dimensional wettability anisotropies. Different types of meshes were used depending on the desired micropatterns shape, size and substrate material. The results revealed the three-dimensional anisotropic micropits pattern with depth profiles, which would be applicable for the confinement and patterning of cells and biomolecules. In addition, the proposed method is applicable for creating selectively activated polymer surface as a substrate for further atomic layer deposition. Moreover, we demonstrate a low cost and fast mass productive method for patterning a viscous polymer liquid in a micro-sized scale

  2. Structural Insights into the Interactions between Platelet Receptors and Fibrillar Collagen*

    OpenAIRE

    Herr, Andrew B.; Farndale, Richard W.

    2009-01-01

    Collagen peptides have been used to identify binding sites for several important collagen receptors, including integrin α2β1, glycoprotein VI, and von Willebrand factor. In parallel, the structures of these collagen receptors have been reported, and their interactions with collagen peptides have been studied. Recently, the three-dimensional structure of the intact type I collagen fiber from rat tail tendon has been resolved by fiber diffraction. It is now possible to map the binding sites of ...

  3. Three-dimensional optical holography using a plasmonic metasurface

    Science.gov (United States)

    Huang, Lingling; Chen, Xianzhong; Mühlenbernd, Holger; Zhang, Hao; Chen, Shumei; Bai, Benfeng; Tan, Qiaofeng; Jin, Guofan; Cheah, Kok-Wai; Qiu, Cheng-Wei; Li, Jensen; Zentgraf, Thomas; Zhang, Shuang

    2013-01-01

    Benefitting from the flexibility in engineering their optical response, metamaterials have been used to achieve control over the propagation of light to an unprecedented level, leading to highly unconventional and versatile optical functionalities compared with their natural counterparts. Recently, the emerging field of metasurfaces, which consist of a monolayer of photonic artificial atoms, has offered attractive functionalities for shaping wave fronts of light by introducing an abrupt interfacial phase discontinuity. Here we realize three-dimensional holography by using metasurfaces made of subwavelength metallic nanorods with spatially varying orientations. The phase discontinuity takes place when the helicity of incident circularly polarized light is reversed. As the phase can be continuously controlled in each subwavelength unit cell by the rod orientation, metasurfaces represent a new route towards high-resolution on-axis three-dimensional holograms with a wide field of view. In addition, the undesired effect of multiple diffraction orders usually accompanying holography is eliminated.

  4. SNAP-3D: a three-dimensional neutron diffusion code

    International Nuclear Information System (INIS)

    A preliminary report is presented describing the data requirements of a one- two- or three-dimensional multi-group diffusion code, SNAP-3D. This code is primarily intended for neutron diffusion calculations but it can also carry out gamma calculations if the diffuse approximation is accurate enough. It is suitable for fast and thermal reactor core calculations and for shield calculations. It is assumed the reader is familiar with the older, two-dimensional code SNAP and can refer to the report [TRG-Report-1990], describing it. The present report concentrates on the enhancements to SNAP that have been made to produce the three-dimensional version, SNAP-3D, and is intended to act a a guide on data preparation until a single, comprehensive report can be published. (author)

  5. Dynamic three-dimensional tagged imaging of left ventricular contraction

    International Nuclear Information System (INIS)

    This paper reports on a method, cardiac tagging with MR imaging, used to assess ventricular deformation during the cardiac cycle. Twenty human volunteers were examined. Six short-axis images of the left ventricle placed to encompass the entire left ventricle were acquired with six radially distributed linear tags generated at the R wave of the electrocardiogram. A series of six images in the long axis of left ventricle with six equidistant tags extending from apex to base parallel to the short axis of the ventricle were also obtained to determine the amount of apex-to-base translation. An inhouse computer program was used to determine automatically the epicardial, endocardial, and tag contours. A three-dimensional wire frame construct was then generated to serve as the data base for a dynamic three-dimensional display of the contracting ventricle as well as to measure the main components of strain

  6. Photodisintegration of 3H in a three dimensional Faddeev approach

    International Nuclear Information System (INIS)

    An interaction of a photon with 3H nuclei is investigated based on a three dimensional Faddeev approach. In this approach The three-nucleon Faddeev equations with two-nucleon interactions are formulated with consideration of the magnitudes of the vector Jacobi momenta and the angle between them with the inclusion of the spin-isospin quantum numbers, without employing a partial wave decomposition. In this calculation the two body t matrices and triton wave function with nd scattering are calculated in the three dimensional approach using AV18 potential. The standard single nucleon current and π-and ρ-like two-body currents have been used which fulfill the current continuity equation together with the corresponding parts of the AV18 potential. Finally the calculated observables are compared with the results of partial wave one and the experimental data.

  7. Refined similarity hypothesis using three-dimensional local averages

    Science.gov (United States)

    Iyer, Kartik P.; Sreenivasan, Katepalli R.; Yeung, P. K.

    2015-12-01

    The refined similarity hypotheses of Kolmogorov, regarded as an important ingredient of intermittent turbulence, has been tested in the past using one-dimensional data and plausible surrogates of energy dissipation. We employ data from direct numerical simulations, at the microscale Reynolds number Rλ˜650 , on a periodic box of 40963 grid points to test the hypotheses using three-dimensional averages. In particular, we study the small-scale properties of the stochastic variable V =Δ u (r ) /(rɛr) 1 /3 , where Δ u (r ) is the longitudinal velocity increment and ɛr is the dissipation rate averaged over a three-dimensional volume of linear size r . We show that V is universal in the inertial subrange. In the dissipation range, the statistics of V are shown to depend solely on a local Reynolds number.

  8. Three-dimensional optical encryption based on ptychography

    Science.gov (United States)

    Zhang, Jun; Li, Tuo; Wang, Yali; Qiao, Liang; Yang, Xiubo; Shi, Yishi

    2015-10-01

    We propose a novel optical encryption system for three-dimension imaging combined with three-dimension Ptychography. Employing the proposed cryptosystem, a 3D object can be encrypted and decrypted successfully. Compared with the conventional three-dimensional cryptosystem, not only encrypting the pure amplitude 3D object is available, but also the encryption of complex amplitude 3D object is achievable. Considering that the probes overlapping with each other is the crucial factor in ptychography, their complex-amplitude functions can serve as a kind of secret keys that lead to the enlarged key space and the enhanced system security. Varies of simulation results demonstrate that the feasibility and robust of the cryptosystem. Furthermore, the proposed system could also be used for other potential applications, such as three-dimensional information hiding and multiple images encryption.

  9. Three Dimensional Energy Transmitting Boundary in the Time Domain

    Directory of Open Access Journals (Sweden)

    Naohiro eNakamura

    2015-11-01

    Full Text Available Although the energy transmitting boundary is accurate and efficient for the FEM earthquake response analysis, it could be applied in the frequency domain only. In the previous papers, the author proposed an earthquake response analysis method using the time domain energy transmitting boundary for two dimensional problems. In this paper, this technique is expanded for three dimensional problems. The inner field is supposed to be a hexahedron shape and the approximate time domain boundary is explained, first. Next, two dimensional anti-plane time domain boundary is studied for a part of the approximate three dimensional boundary method. Then, accuracy and efficiency of the proposed method are confirmed by example problems.

  10. Analytical Prediction of Three Dimensional Chatter Stability in Milling

    Science.gov (United States)

    Altintas, Yusuf

    The chip regeneration mechanism during chatter is influenced by vibrations in three directions when milling cutters with ball end, bull nose, or inclined cutting edges are used. A three dimensional chatter stability is modeled analytically in this article. The dynamic milling system is formulated as a function of cutter geometry, the frequency response of the machine tool structure at the cutting zone in three Cartesian directions, cutter engagement conditions and material property. The dynamic milling system with nonlinearities and periodic delayed differential equations is reduced to a three dimensional linear stability problem by approximations based on the physics of milling. The chatter stability lobes are predicted in the frequency domain using the proposed analytical solution, and verified experimentally in milling a Titanium alloy with a face milling cutter having circular inserts.

  11. Three-Dimensional Modeling of Guide-Field Magnetic Reconnection

    Science.gov (United States)

    Hesse, Michael

    2005-01-01

    The dissipation mechanism of guide field magnetic reconnection remains a subject of intense scientific interest. On one hand, one set of recent studies have shown that particle inertia-based processes, which include thermal and bulk inertial effects, provide the reconnection electric field in the diffusion region. On the other hand, a second set of studies emphasizes the role of wave-particle interactions in providing anomalous resistivity in the diffusion region. In this presentation, we analyze three-dimensional PIC simulations of guide-field magnetic reconnection. Specific emphasis will be on the question whether thermal-inertia processes, mediated by the electron pressure tensor, remain a viable dissipation mechanism in fully three-dimensional systems.

  12. Resistive drift wave turbulence in a three-dimensional geometry

    DEFF Research Database (Denmark)

    Korsholm, Søren Bang; Michelsen, Poul; Naulin, V.

    1999-01-01

    The Hasegawa-Wakatani model describing resistive drift waves is investigated analytically and numerically in a three-dimensional periodic geometry. After an initial growth of the energy the drift waves couple nonlinearly to convective cells, which eventually dominate the system completely. An app...... approach to include more physical boundary conditions to the system is presented. This changes the results of the simulations significantly. (C) 1999 American Institute of Physics.......The Hasegawa-Wakatani model describing resistive drift waves is investigated analytically and numerically in a three-dimensional periodic geometry. After an initial growth of the energy the drift waves couple nonlinearly to convective cells, which eventually dominate the system completely. An...

  13. Jamming vs Caging in Three Dimensional Jamming Percolation

    Science.gov (United States)

    Shokef, Yair; Segall, Nimrod; Teomy, Eial

    We study a three-dimensional kinetically-constrained lattice-gas model, in which the ability of a particle to move depends on the occupation of neighboring sites in an orientational manner. The kinetic rules are constructed such that chains of permanently-frozen particles reach an infinite length at the critical density of directed percolation. Thus at this critical density the system undergoes a jamming transition, above which there is a finite fraction of jammed particles. We demonstrate that the three-dimensional mesh-like structure of the one-dimensional jammed chains enables the free particles to propagate through the holes in this mesh. This diffusive motion is terminated at a second critical density above which all particles are caged. The largest and second largest clusters of dynamically-connected sites exhibit singularities at both densities. Thus our model assists in separating between the two distinct phenomena of jamming and caging.

  14. Three-dimensional surface reconstruction for industrial computed tomography

    Science.gov (United States)

    Vannier, M. W.; Knapp, R. H.; Gayou, D. E.; Sammon, N. P.; Butterfield, R. L.; Larson, J. W.

    1985-01-01

    Modern high resolution medical computed tomography (CT) scanners can produce geometrically accurate sectional images of many types of industrial objects. Computer software has been developed to convert serial CT scans into a three-dimensional surface form, suitable for display on the scanner itself. This software, originally developed for imaging the skull, has been adapted for application to industrial CT scanning, where serial CT scans thrrough an object of interest may be reconstructed to demonstrate spatial relationships in three dimensions that cannot be easily understood using the original slices. The methods of three-dimensional reconstruction and solid modeling are reviewed, and reconstruction in three dimensions from CT scans through familiar objects is demonstrated.

  15. Three-dimensional transport with variational nodal methods

    International Nuclear Information System (INIS)

    The development of the variational nodal method contained in the three-dimensional transport code VARIANT is reviewed. This Argonne National Laboratory code treats two- and three-dimensional multigroup problems with anisotropic scattering in hexagonal and Cartesian geometries. The methodology couples hybrid finite elements in space, enforcing nodal balance, with spherical harmonics expansions in angle. The resulting response matrix equations are solved by red-black or four-colour iterations. Several enhancements to VARIANT are discussed. The simplified spherical harmonics option provides near spherical harmonic accuracy for many problems at a fraction of the cost. Adjoint and perturbation calculations are performed without the physical and mathematical adjoint dichotomy appearing in other nodal methods. Heterogeneous node methods extend the problem classes to which the method may be applied. Computational strategies and trade-off are discussed and possible future research directions are outlined. (author)

  16. Dimer problem for some three dimensional lattice graphs

    Science.gov (United States)

    Lin, Fenggen; Chen, Ailian; Lai, Jiangzhou

    2016-02-01

    Dimer problem for three dimensional lattice is an unsolved problem in statistical mechanics and solid-state chemistry. In this paper, we obtain asymptotical expressions of the number of close-packed dimers (perfect matchings) for two types of three dimensional lattice graphs. Let M(G) denote the number of perfect matchings of G. Then log(M(K2 ×C4 ×Pn)) ≈(- 1.171 ṡn-1.1223 + 3.146) n, and log(M(K2 ×P4 ×Pn)) ≈(- 1.164 ṡn-1.196 + 2.804) n, where log() denotes the natural logarithm. Furthermore, we obtain a sufficient condition under which the lattices with multiple cylindrical and multiple toroidal boundary conditions have the same entropy.

  17. Three-dimensional Microarchitecture of Adolescent Cancellous Bone

    DEFF Research Database (Denmark)

    Ding, Ming; Hvid, I; Overgaard, Søren

    regarding three-dimensional (3-D) microarchitecture of normal adolescent cancellous bone. The objective of this study was to investigate 3-D microarchitecture of normal adolescent cancellous bone, and compared them with adult cancellous bone, thus seeking more insight into the subchondral bone adaptations...... during development and growth. We hypothesized that adolescent cancellous bone differed significantly from adult cancellous bone in their microarchitecture and mechanical properties. METHODS: Twenty-three human proximal tibiae were harvested and divided into 3 groups according to their ages: adolescence...... Orthopaedics & Traumatology and Institute of Forensic Medicine, Odense and Aarhus University Hospitals, Denmark. RESULTS: Three-dimensional reconstructions of cancellous bone from micro-CT imaging are shown in Figure 1. Our data showed that trabecular separation was significantly greater in the adolescence...

  18. Three-Dimensional Dynamical Instabilities in Galactic Ionization Fronts

    CERN Document Server

    Whalen, D J; Whalen, Daniel J.; Norman, Michael L.

    2007-01-01

    Ionization front instabilities have long been of interest for their suspected role in a variety of phenomena in the galaxy, from the formation of bright rims and 'elephant trunks' in nebulae to triggered star formation in molecular clouds. Numerical treatments of these instabilities have historically been limited in both dimensionality and input physics, leaving important questions about their true evolution unanswered. We present the first three-dimensional radiation hydrodynamical calculations of both R-type and D-type ionization front instabilities in galactic environments (i.e., solar metallicity gas). Consistent with linear stability analyses of planar D-type fronts, our models exhibit many short-wavelength perturbations growing at early times that later evolve into fewer large-wavelength structures. The simulations demonstrate that both self-consistent radiative transfer and three-dimensional flow introduce significant morphological differences to unstable modes when compared to earlier two-dimensional ...

  19. Three-dimensional computed tomography of the carpal ligaments.

    Science.gov (United States)

    Nanno, Mitsuhiko; Viegas, Steven F

    2009-03-01

    This article details a current perspective and accurate anatomical three-dimensional descriptions of the ligaments of the wrist. The carpometacarpal ligaments, the intercarpal ligaments, and the radiocarpal ligaments are described and illustrated using a unique combination of detailed dissection, computed tomography, and a three-dimensional digitization technique. Detailed information is also provided about the ligamentous attachments of the carpometacarpal joints, the carpal bones, and the distal radius. This study improves knowledge and understanding of the normal anatomy and mechanics of the radiocarpal and intercarpal ligaments and the carpometacarpal joints, and it should help in the assessment of radiographic images and treatment of various injuries and degenerative changes seen in the wrist. The knowledge of the ligaments will further serve as a foundation for understanding the anatomy of the ligaments, the biomechanics of the wrist, and the function of the individual ligaments and their roles in joint motion and stability. PMID:19235667

  20. Application of Monte Carlo simulation for three-dimensional flows

    Science.gov (United States)

    Scheurlen, M.; Noll, B.; Wittig, S.

    1992-02-01

    A Monte Carlo technique is outlined for the simulation of the transport of a joint scalar probability density function (PDF). The discretization of the partial differential equations is based on a finite volume approximation. The problem of frozen solutions is addressed if the number of stochastic elements is limited. Non-adiabatic boundary conditions are discussed if the energy equation is solved by a Monte Carlo simulation. The Monte Carlo simulation is compared with deterministic calculations and with an experiment in a three dimensional non-isothermal non-reacting jet mixing flow. The results of the simulation agree very well with the experiment and the deterministic calculations. However, the computer time and storage requirements for a three dimensional simulation of the transport of a single scalar PDF increases dramatically in comparison to deterministic calculations. The results also indicate the need for a simulation procedure that is free of numerical diffusion.

  1. Collective modes in three-dimensional magnonic vortex crystals

    Science.gov (United States)

    Hänze, Max; Adolff, Christian F.; Schulte, Benedikt; Möller, Jan; Weigand, Markus; Meier, Guido

    2016-03-01

    Collective modes in three-dimensional crystals of stacked permalloy disks with magnetic vortices are investigated by ferromagnetic resonance spectroscopy and scanning transmission X-ray microscopy. The size of the arrangements is increased step by step to identify the different contributions to the interaction between the vortices. These contributions are the key requirement to understand complex dynamics of three dimensional vortex crystals. Both vertical and horizontal coupling determine the collective modes. In-plane dipoles strongly influence the interaction between the disks in the stacks and lead to polarity-dependent resonance frequencies. Weaker contributions discern arrangements with different polarities and circularities that result from the lateral coupling of the stacks and the interaction of the core regions inside a stack. All three contributions are identified in the experiments and are explained in a rigid particle model.

  2. The factorization method for three dimensional electrical impedance tomography

    International Nuclear Information System (INIS)

    The use of the factorization method for electrical impedance tomography has been proved to be very promising for applications in the case where one wants to find inhomogeneous inclusions in a known background. In many situations, the inspected domain is three dimensional and is made of various materials. In this case, the main challenge in applying the factorization method is in computing the Neumann Green's function of the background medium. We explain how we solve this difficulty and demonstrate the capability of the factorization method to locate inclusions in realistic inhomogeneous three dimensional background media from simulated data obtained by solving the so-called complete electrode model. We also perform a numerical study of the stability of the factorization method with respect to various modelling errors. (paper)

  3. Three Dimensional Numerical Relativity with a Hyperbolic Formulation

    CERN Document Server

    Bona, C; Seidel, E; Walker, P; Bona, Carles; Masso, Joan; Seidel, Edward; Walker, Paul

    1998-01-01

    We discuss a successful three-dimensional cartesian implementation of the Bona-Massó hyperbolic formulation of the 3+1 Einstein evolution equations in numerical relativity. The numerical code, which we call ``Cactus,'' provides a general framework for 3D numerical relativity, and can include various formulations of the evolution equations, initial data sets, and analysis modules. We show important code tests, including dynamically sliced flat space, wave spacetimes, and black hole spacetimes. We discuss the numerical convergence of each spacetime, and also compare results with previously tested codes based on other formalisms, including the traditional ADM formalism. This is the first time that a hyperbolic reformulation of Einstein's equations has been shown appropriate for three-dimensional numerical relativity in a wide variety of spacetimes.

  4. Identification of Jiangxi wines by three-dimensional fluorescence fingerprints

    Science.gov (United States)

    Wan, Yiqun; Pan, Fengqin; Shen, Mingyue

    2012-10-01

    A new assay of identifying wines was developed based on fingerprints of three-dimensional fluorescence spectra, and 30 samples from different manufacturers were analyzed. The techniques of principal component analysis (PCA) and hierarchical cluster analysis (HCA) were used to differentiate and evaluate the character parameters of wines' three-dimensional fluorescence spectra. At the same time, the back-propagation network (BPN) was applied to predict the attribution of unknown samples. The results of PCA and HCA showed that there was definite different information among the wine samples from different manufacturers. It was promising that the method could be applied to distinguish wine samples produced by different manufacturers. The proposed method could provide the criterion for the quality control of wines.

  5. Using SAP to calculate three-dimensional stress concentration effects

    Energy Technology Data Exchange (ETDEWEB)

    Goodzeit, C.L.

    1977-01-01

    SAP has been used to calculate stress distributions around local structural discontinuities in three-dimensional structures by using a large element model for the complete structure and a small element, detailed model for the discontinuity. Displacement boundary conditions are imposed on the fine grid model by using a three-dimensional spatial interpolation from the displacements calculated for the large element model. Processors are described which prepare the necessary boundary element input data from the displacements of the large element model using the described spatial interpolation technique. An example is given illustrating how this method is used to calculate the triaxial stresses in a fillet radius in a dynamically loaded structure. In addition, a post processor is described which averages the nodal point stresses and calculates the principal stresses.

  6. On the Three-dimensional Central Moment Lattice Boltzmann Method

    CERN Document Server

    Premnath, Kannan N; 10.1007/s10955-011-0208-9

    2012-01-01

    A three-dimensional (3D) lattice Boltzmann method based on central moments is derived. Two main elements are the local attractors in the collision term and the source terms representing the effect of external and/or self-consistent internal forces. For suitable choices of the orthogonal moment basis for the three-dimensional, twenty seven velocity (D3Q27), and, its subset, fifteen velocity (D3Q15) lattice models, attractors are expressed in terms of factorization of lower order moments as suggested in an earlier work; the corresponding source terms are specified to correctly influence lower order hydrodynamic fields, while avoiding aliasing effects for higher order moments. These are achieved by successively matching the corresponding continuous and discrete central moments at various orders, with the final expressions written in terms of raw moments via a transformation based on the binomial theorem. Furthermore, to alleviate the discrete effects with the source terms, they are treated to be temporally semi-...

  7. SHETAN - a three dimensional transport code for reactor analysis

    International Nuclear Information System (INIS)

    SHETAN, a three-dimensional neutron transport code, is based on the block method of solving the integral transport equation, which combines the advantages of the conventional collision probability method and the interface current technique and has made possible a large increase in the size of problem that can be handled. The code mixed rectangular and cylindrical coordinates, allowing cylindrical fuel channels and reactivity devices to be modelled within a rectangular cell. Details of the calculational method for the collision probabilities in these mixed coordinates are described. Applications of SHETAN to analyze booster and adjuster experiments done in the ZED-2 reactor are also described. Satisfactory agreement with measurements confirm that SHETAN is a useful tool for reactor analyses where three-dimensional calculations are required. (auth)

  8. Three-Dimensional Structure of Solar Wind Turbulence

    CERN Document Server

    Chen, C H K; Schekochihin, A A; Horbury, T S; Wicks, R T; Bale, S D

    2011-01-01

    We have measured, for the first time, the three-dimensional structure of inertial range plasma turbulence in the fast solar wind with respect to a local, physically motivated coordinate system. We found that the incompressible Alfvenic fluctuations are three-dimensionally anisotropic, with the sense of this anisotropy changing from large to small scales. At the largest scales, the magnetic field correlations are longest in the local fluctuation direction, consistent with Alfven waves. At the smallest scales, they are longest along the local mean field direction and shortest in the direction perpendicular to the local mean field and the local field fluctuation. The compressive fluctuations are highly elongated along the local mean magnetic field direction, although axially symmetric perpendicular to it. Their large anisotropy may explain why they are not heavily damped.

  9. Three-dimensional metamaterials fabricated using Proton Beam Writing

    International Nuclear Information System (INIS)

    Proton Beam Writing (PBW) is a direct write lithographic technique that has recently been applied to the fabrication of three dimensional metamaterials. In this work, we show that the unique capabilities of PBW, namely the ability to fabricate arrays of high resolution, high aspect ratio microstructures in polymer or replicated into metal, is well suited to metamaterials research. We have also developed a novel method for selectively electroless plating silver directly onto polymer structures that were fabricated using PBW. This method opens up new avenues for utilizing PBW for making metamaterials and other sub-wavelength metallic structures. Several potential applications of three dimensional metamaterials fabricated using PBW are discussed, including sensing and negative refractive index materials

  10. Three-dimensional metamaterials fabricated using Proton Beam Writing

    Energy Technology Data Exchange (ETDEWEB)

    Bettiol, A.A., E-mail: a.bettiol@nus.edu.sg [Centre for Ion Beam Applications, Department of Physics, National University of Singapore, 2 Science Dr. 3, Singapore 117542 (Singapore); Turaga, S.P.; Yan, Y.; Vanga, S.K. [Centre for Ion Beam Applications, Department of Physics, National University of Singapore, 2 Science Dr. 3, Singapore 117542 (Singapore); Chiam, S.Y. [NUS High School for Maths and Science, 20 Clementi Avenue 1, Singapore 129957 (Singapore)

    2013-07-01

    Proton Beam Writing (PBW) is a direct write lithographic technique that has recently been applied to the fabrication of three dimensional metamaterials. In this work, we show that the unique capabilities of PBW, namely the ability to fabricate arrays of high resolution, high aspect ratio microstructures in polymer or replicated into metal, is well suited to metamaterials research. We have also developed a novel method for selectively electroless plating silver directly onto polymer structures that were fabricated using PBW. This method opens up new avenues for utilizing PBW for making metamaterials and other sub-wavelength metallic structures. Several potential applications of three dimensional metamaterials fabricated using PBW are discussed, including sensing and negative refractive index materials.

  11. Perceived three-dimensional shape toggles perceived glow.

    Science.gov (United States)

    Kim, Minjung; Wilcox, Laurie M; Murray, Richard F

    2016-05-01

    Most surfaces reflect light from external sources, but others emit light: they glow. Glowing surfaces are often a sign of an important feature of the environment, such as a heat source or a bioluminescent life form, but we know little about how the human visual system identifies them. Previous work has shown that luminance and luminance gradients are important in glow perception [1,2]. While a link between glow and shape has been suggested in the literature [3], there has been no systematic investigation of this relationship. Here we show that perceived three-dimensional shape plays a decisive role in glow perception; vivid percepts of glow can be toggled on and off, simply by changing cues to three-dimensional shape while holding other image features constant. PMID:27166688

  12. The Inherently Three-Dimensional Nature of Magnetized Plasma Turbulence

    CERN Document Server

    Howes, Gregory G

    2013-01-01

    It is often asserted or implicitly assumed, without justification, that the results of two-dimensional investigations of plasma turbulence are applicable to the three-dimensional plasma environments of interest. A projection method is applied to derive two scalar equations that govern the nonlinear evolution of the Alfvenic and pseudo-Alfvenic components of ideal incompressible magnetohydrodynamic (MHD) plasma turbulence. The mathematical form of these equations makes clear the inherently three-dimensional nature of plasma turbulence, enabling an analysis of the nonlinear properties of two-dimensional limits often used to study plasma turbulence. In the anisotropic limit k_perp >>k_parallel that naturally arises in magnetized plasma systems, the perpendicular 2D limit retains the dominant nonlinearities that are mediated only by the Alfvenic fluctuations but lacks the wave physics associated with the linear term that is necessary to capture the anisotropic cascade of turbulent energy. In the in-plane 2D limit...

  13. The NRCC three-dimensional image data files

    Science.gov (United States)

    Rioux, M.; Cournoyer, L.

    1988-06-01

    This book contains a catalogue of illustrations related to three dimensional image data files taken at the National Research Council of Canada laboratories. The images were taken with a camera based on a synchronized scanner recently developed at the Division of Electrical Engineering. The purpose of the work is to provide computer scientists with a bank of three dimensional images which can be used in research activities such as (1) integration of multiple views of the same object to form a model, (2) creation of a library of object models to investigate searching algorithms, and (3) image description, development of iterative processes to measure, manipulate, and edit 3-D information. The images are available on magnetic tape or on diskette. A description of the camera and its imaging modes is included.

  14. Three-dimensional hybrid networks based on aspartic acid

    Indian Academy of Sciences (India)

    Anupama Ghosh; R A Sanguramath

    2008-01-01

    Three-dimensional achiral coordination polymers of the general formula M2(D, L-NHCH (COO)CH2COO)2.C4H4N2 where M = Ni and Co and pyrazine acts as the linker molecule have been prepared under hydrothermal conditions starting with [M(L-NHCH(COO)CH2COO).3H2O] possessing a helical chain structure. A three-dimensional hybrid compound of the formula Pb2.5[N{CH(COO)CH2COO}22H2O] has also been prepared hydrothermally starting with aspartic acid and Pb(NO3)2. In this lead compound, where a secondary amine formed by the dimerisation of aspartic acid acts as the ligand, there is two-dimensional inorganic connectivity and one-dimensional organic connectivity.

  15. Three-dimensional MR imaging of congenital heart disease

    International Nuclear Information System (INIS)

    Contiguous 5-mm thick ECG-gated MR images of the thorax were edited using surface reconstruction techniques to produce three-dimensional (3D) images of the heart and great vessels in four healthy individuals and 25 patients with congenital heart disease (aged 3 months-30 years). Anomalies studied include atrial and ventricular septal defects, aortic coarctation, AV canal defects, double outlet ventricles, hypoplastic left heart syndrome, and a wide spectrum of patients with tetralogy of Fallot. The results were correlated with echocardiographic and cineradiographic studies, and with surgical findings or pathologic specimens. Three-dimensional reconstructions accurately localized the dimensions and locations of all cardiac and great vessel anomalies and often displayed anatomic findings not diagnosed or visualized with other forms of diagnostic imaging

  16. Informatics solutions for Three-dimensional visualization in real time

    International Nuclear Information System (INIS)

    The advances reached in the development of the hardware and in the methods of acquisition of data like tomographic scanners and systems of analysis of images, have allowed obtaining geometric models of biomedical elements with the property of being manipulated through the three-dimensional visualization (3D). Nowadays, this visualization embraces from biological applications, including analysis of structures and its functional relationships, until medical applications that include anatomical accuracies and the planning or the training for complex surgical operations. This work proposes computer solutions to satisfy visualization requirements in real time. The developed algorithms are contained in a graphic library that will facilitate the development of future works. The obtained results allow facing current problems of three-dimensional representation of complex surfaces, realism is reached in the images and they have possible application in bioinformatics and medicine

  17. Horizontal-vertical coupling for three dimensional laser cooling

    International Nuclear Information System (INIS)

    In order to achieve three dimensional crystal beam, laser cooling forces are required not only in the longitudinal direction, but also in the transverse directions. With the resonance coupling method, transverse temperature is transmitted into longitudinal direction, and we have already demonstrated the horizontal laser cooling experimentally. In the present paper, we will describe an approach to extend this result to three dimensional cooling. The vertical cooling requires that the horizontal oscillation couples with the vertical oscillation. For achieving horizontal-vertical coupling, the solenoid in electron beam cooling apparatus is utilized with an experiment (νx =2.07, νy=1.07). For various solenoidal magnetic fields from 0 to 100 Gauss, horizontal and vertical betatron tunes are measured by beam transfer function. For a certain region of the solenoidal magnetic field, these tunes are mixed up each other. (author)

  18. Three-Dimensional All-Dielectric Photonic Topological Insulator

    CERN Document Server

    Slobozhanyuk, Alexey; Ni, Xiang; Smirnova, Daria; Kivshar, Yuri S; Khanikaev, Alexander B

    2016-01-01

    The discovery of two-dimensional topological photonic systems has transformed our views on electromagnetic propagation and scattering of classical waves, and a quest for similar states in three dimensions, known to exist in condensed matter systems, has been put forward. Here we demonstrate that symmetry protected three-dimensional topological states can be engineered in an all-dielectric platform with the electromagnetic duality between electric and magnetic fields ensured by the structure design. Magneto-electric coupling playing the role of a synthetic gauge field leads to a topological transition to an insulating regime with a complete three-dimensional photonic bandgap. An emergence of surface states with conical Dirac dispersion and spin-locking is unimpeded. Robust propagation of surface states along two-dimensional domain walls defined by the reversal of magneto-electric coupling is confirmed numerically by first principle studies. It is shown that the proposed system represents a table-top platform f...

  19. Measuring three-dimensional interaction potentials using optical interference

    OpenAIRE

    Mojarad, Nassiredin; Sandoghdar, Vahid; Krishnan, Madhavi

    2013-01-01

    We describe the application of three-dimensional (3D) scattering interferometric (iSCAT) imaging to the measurement of spatial interaction potentials for nano-objects in solution. We study electrostatically trapped gold particles in a nanofluidic device and present details on axial particle localization in the presence of a strongly reflecting interface. Our results demonstrate high-speed (~kHz) particle tracking with subnanometer localization precision in the axial and average 2.5 nm in the ...

  20. Three-dimensional measurement of foot arch in preschool children

    OpenAIRE

    Chang Hsun-Wen; Lin Chien-Ju; Kuo Li-Chieh; Tsai Ming-June; Chieh Hsiao-Feng; Su Fong-Chin

    2012-01-01

    Abstract Background The prevalence of flexible flatfoot is high among preschool-aged children, but the effects of treatment are inconclusive due to the unclear definitions of normal flatfoot. To date, a universally accepted evaluation method of the foot arch in children has not been completely established. Our aims of this study were to establish a new method to evaluate the foot arch from a three dimensional perspective and to investigate the flexibility of the foot arch among children aged ...

  1. Three-dimensional measurement of foot arch in preschool children

    OpenAIRE

    Chang, Hsun-Wen; Lin, Chien-Ju; Kuo, Li-Chieh; Tsai, Ming-June; Chieh, Hsiao-Feng; Su, Fong-Chin

    2012-01-01

    Background The prevalence of flexible flatfoot is high among preschool-aged children, but the effects of treatment are inconclusive due to the unclear definitions of normal flatfoot. To date, a universally accepted evaluation method of the foot arch in children has not been completely established. Our aims of this study were to establish a new method to evaluate the foot arch from a three dimensional perspective and to investigate the flexibility of the foot arch among children aged from two ...

  2. A Three-dimensional Model of Poroviscous Aquifer Deformation

    OpenAIRE

    Jeng, D. Isaac

    2005-01-01

    A mathematical model is developed for quantification of aquifer deformation due to ground-water withdrawal and, with some modifications, is potentially applicable to petroleum reservoirs. A porous medium saturated with water is conceptually treated in the model as a nonlinearly viscous fluid continuum. The model employs a new three-dimensional extension, made in this thesis, of Helm's poroviscosity as a constitutive law governing the stress-strain relation of material deformation and Gerse...

  3. Three-Dimensional Molecular Modeling of Bovine Caseins

    OpenAIRE

    Farrell, Harold M., Jr.; Brown, Eleanor M.; Kumosinski, Thomas F.

    1993-01-01

    Three-dimensional (3 -D) structures derived from X-ray crystallography are important in elucidating structure- function relationships for many proteins. However, not all food proteins can be crystallized. The casei ns of bovine milk are one class of non-crysta11izable proteins (a, 1-, K-, and /3-). The complete primary and partial secondary structures of these proteins are known, but homologous proteins of known crystallographic structure cannot be found. Therefore , sequence based prediction...

  4. Diffusive Quantum Criticality in Three Dimensional Disordered Dirac Semimetals

    OpenAIRE

    Roy, Bitan; Sarma, S. Das

    2014-01-01

    Three dimensional Dirac semimetals are stable against weak potential disorder, but not against strong disorder. In the language of renormalization group, such stability stems from the irrelevance of weak disorder in the vicinity of the noninteracting Gaussian fixed point. However, beyond a threshold, potential disorder can take Dirac semimetals into a compressible diffusive metallic phase through a quantum phase transition (QPT), where density of states at zero energy, quasiparticle lifetime ...

  5. Input Device with Three-Dimensional Image Display

    DEFF Research Database (Denmark)

    2012-01-01

    The present invention relates to an input device (2), such as a keyboard, comprising plurality of activation parts (4) for depression, at least one registration part (6) for individual registration of depression of activation parts, and at least one image displaying part (8), where depression of ...... the activation parts (4) provides tactile feedback to a user. The at least one image displaying part (8) is configured for displaying a label of an activation part (4) as a three-dimensional label....

  6. A Three-Dimensional Angular Scattering Response Including Path Powers

    OpenAIRE

    Mammasis, Kostantinos; Santi, Paolo; Goulianos, Angelos

    2011-01-01

    In this paper the angular power spectrum exhibited under a three-dimensional (3-D) Gaussian scatter distribution at fixed observation points in space is investigated. Typically, these correspond to the mobile and base units respectively. Unlike other spatial channel models, the derived model accounts for the distance to each scatterer from the observation point and transforms distances into power values under the assumption of free-space propagation. The proposed 3-D spatial channel model fol...

  7. A Three Dimensional Simulation Method of the Gantry Crane

    OpenAIRE

    Li, Jingsong; Hang Su; Quan Liu

    2013-01-01

    Until now, many companies have developed lots of the port machinery remote monitoring systems. However, these monitoring systems usual display the operating status of the port machinery by the schematic diagram, Legend and data. The presentation of information is unable to describe the status of the large number of port machinery. In order to solve the problem, a three-dimensional simulation method of the gantry crane based on the WPF is proposed. This paper studies WPF technology and 3D mode...

  8. A Novel Three-Dimensional Tool for Teaching Human Neuroanatomy

    OpenAIRE

    Estevez, Maureen E.; Lindgren, Kristen A.; Bergethon, Peter R.

    2010-01-01

    Three-dimensional (3-D) visualization of neuroanatomy can be challenging for medical students. This knowledge is essential in order for students to correlate cross-sectional neuroanatomy and whole brain specimens within neuroscience curricula and to interpret clinical and radiological information as clinicians or researchers. This study implemented and evaluated a new tool for teaching 3-D neuroanatomy to first-year medical students at Boston University School of Medicine. Students were rando...

  9. Oscillatory crossover from two dimensional to three dimensional topological insulators

    OpenAIRE

    Liu, Chao-Xing; Zhang, Haijun; Yan, Binghai; Qi, Xiao-Liang; Frauenheim, Thomas; Dai, Xi; Fang, Zhong; Zhang, Shou-Cheng

    2009-01-01

    We investigate the crossover regime from three dimensional topological insulators $Bi_2Te_3$ and $Bi_2Se_3$ to two dimensional topological insulators with quantum spin Hall effect when the layer thickness is reduced. Using both analytical models and first-principles calculations, we find that the crossover occurs in an oscillatory fashion as a function of the layer thickness, alternating between topologically trivial and non-trivial two dimensional behavior.

  10. Three-dimensional photon counting double-random-phase encryption.

    Science.gov (United States)

    Cho, Myungjin; Javidi, Bahram

    2013-09-01

    In this Letter, we present a three-dimensional (3D) photon counting double-random-phase encryption (DRPE) technique using passive integral imaging. A 3D photon counting DRPE can encrypt a 3D scene and provides more security and authentications due to photon counting Poisson nonlinear transformation on the encrypted image. In addition, 3D imaging allows verification of the 3D object at different depths. Preliminary results and performance evaluation have been presented. PMID:23988912

  11. Three dimensional structure and morphology of pelagic fish schools

    OpenAIRE

    Paramo, J.; Gerlotto, François; Oyarzun, C.

    2010-01-01

    In fish resource assessment, it is very important to know about the behaviour and form of fish schools. This paper describes the three-dimensional (3D) morphology and internal structure of pelagic schools observed using vertical-scanning multibeam sonar. The acoustic data were collected in waters off Venezuela, Senegal, and Mexico. The data were used to derive metrics of school location, density, shape and internal structure from a total of 668 schools: 257 from Mexico, 343 from Venezuela and...

  12. Three-dimensional terahertz computed tomography of human bones

    OpenAIRE

    Bessou, Maryelle; Chassagne, Bruno; Caumes, Jean-Pascal; Pradère, Christophe; Maire, Philippe; Tondusson, Marc; Abraham, Emmanuel

    2012-01-01

    Three-dimensional terahertz computed tomography has been used to investigate dried human bones such as a lumbar vertebra, a coxal bone, and a skull, with a direct comparison with standard radiography. In spite of lower spatial resolution compared with x-ray, terahertz imaging clearly discerns a compact bone from a spongy one, with strong terahertz absorption as shown by additional terahertz time-domain transmission spectroscopy.

  13. Time-Domain Simulation of Three Dimensional Quantum Wires.

    Science.gov (United States)

    Sullivan, Dennis M; Mossman, Sean; Kuzyk, Mark G

    2016-01-01

    A method is presented to calculate the eigenenergies and eigenfunctions of quantum wires. This is a true three-dimensional method based on a direct implementation of the time-dependent Schrödinger equation. It makes no approximations to the Schrödinger equation other than the finite-difference approximation of the space and time derivatives. The accuracy of our method is tested by comparing it to analytical results in a cylindrical wire. PMID:27124603

  14. Three dimensional lattice gravity as supersymmetric Yang-Mills theory

    OpenAIRE

    Catterall, Simon

    2010-01-01

    We argue that a certain twisted supersymmetric Yang-Mills theory in three dimensions with gauge group SU(2) possesses a set of topological observables whose expectation values can be computed in a related Chern Simons theory. This Chern Simons theory has been proposed as a definition of three dimensional Euclidean quantum gravity. Since the YM theory admits a discretization which preserves the values of topological observables we conjecture that it can be used as a non-perturbative definition...

  15. Design and Implementation of a Three Dimensional CNC Machine

    OpenAIRE

    Venkata Krishna Pabolu; Prof. Sri K.N.H. Srinivas

    2010-01-01

    This paper discusses the design and implementation of low cost three dimensional computerized numerical control (CNC) machines for Industrial application. The primary function of this microcontrollerbased CNC machine is to cut the metal in to required shape. This discuss is focused on communication between Personal computer (PC) and a numerical control machine. The objective to devise a computer controlled cutting machine arose from increasing demand for flexibility and cutting with respect t...

  16. MRFD Method for Scattering From Three Dimensional Dielectric Bodies

    Directory of Open Access Journals (Sweden)

    A. F. Yagli

    2011-09-01

    Full Text Available A three-dimensional multiresolution frequency domain (MRFD method is established to compute bistatic radar cross sections of arbitrarily shaped dielectric objects. The proposed formulation is successfully verified by computing the bistatic radar cross sections of a dielectric sphere and a dielectric cube. Comparing the results to those obtained from the finite difference frequency domain (FDFD method simulations and analytic calculations, we demonstrated the computational time and memory advantages of MRFD method.

  17. Three-Dimensional Turbomachine-Blade-Row Analysis Code

    Science.gov (United States)

    Glassman, A. J.; Wood, J. R.

    1986-01-01

    Computer program (MERNEW3D) developed that prepares bulk of input data set required for Denton three-dimensional inviscid turbomachine-blade-row analysis code. Denton input generated from minimum of geometry and flow-variable information by using cubic spline curve fits for interpolation and extrapolation. Curve-fitting procedures taken from previously developed and widely used NASA computer program (MERIDL), which performs meridional streamsurface analysis.

  18. Three-dimensional organization of the human interphase nucleus.

    OpenAIRE

    Knoch, Tobias; Münkel, Christian; Waldeck, Waldemar; Langowski, Jörg

    2002-01-01

    textabstractDespite the successful linear sequencing of the human genome its three-dimensional structure is widely unknown, although it is important for gene regulation and replication. For a long time the interphase nucleus has been viewed as a 'spaghetti soup' of DNA without much internal structure, except during cell division. Only recently has it become apparent that chromosomes occupy distinct 'territories' also in interphase. Two models for the detailed folding of the 30 nm chromatin fi...

  19. Confinement induced by fermion damping in three-dimensional QED

    CERN Document Server

    Wang, Jing; Li, Wei; Liu, Guo-Zhu

    2010-01-01

    The three-dimensional non-compact QED is known to exhibit weak confinement when fermions acquire a finite mass via the mechanism of dynamical chiral symmetry breaking. In this paper, we study the effect of fermion damping caused by elastic scattering on the classical potential between fermions. By calculating the vacuum polarization function that incorporates the fermion damping effect, we show that fermion damping can induce a weak confinement even when the fermions are massless and the chiral symmetry is not broken.

  20. Confinement induced by fermion damping in three-dimensional QED

    OpenAIRE

    Jing WANG; Wang, Jing-Rong; Li, Wei; Liu, Guo-Zhu

    2010-01-01

    The three-dimensional non-compact QED is known to exhibit weak confinement when fermions acquire a finite mass via the mechanism of dynamical chiral symmetry breaking. In this paper, we study the effect of fermion damping caused by elastic scattering on the classical potential between fermions. By calculating the vacuum polarization function that incorporates the fermion damping effect, we show that fermion damping can induce a weak confinement even when the fermions are massless and the chir...

  1. Three-Dimensional Multilayered Fibrous Constructs for Wound Healing Applications

    OpenAIRE

    Reis, Tiago C.; Castleberry, Steven; Rego, Ana M. B.; Aguiar-Ricardo, Ana; Hammond, Paula T.

    2016-01-01

    Electrospun materials are promising scaffolds due to their light-weight, high surface-area and low-cost fabrication, however, such scaffolds are commonly obtained as ultrathin two-dimensional non-woven meshes, lacking on topographical specificity and surface side-dependent properties. Herein, it is reported the production of three-dimensional fibrous materials with an asymmetrical inner structure and engineered surfaces. The manufactured constructs evidence fibrous-based microsized conical pr...

  2. A three-dimensional nodal neutron kinetics capability for relaps

    International Nuclear Information System (INIS)

    The incorporation of a three-dimensional neutron kinetics capability into the DOE version of the RELAP5/MOD3.2 reactor safety code is discussed. A brief discussion of the kinetics method is given along with a discussion of the cross section parameterization models available in RELAP5/MOD3.2. The RELAP5/MOD3.2 code is then used to perform calculations of the NEACRP rod ejection and rod withdrawal benchmarks, and results are presented

  3. Negative refraction of a three-dimensional metallic photonic crystal

    CERN Document Server

    Mahmoudi, A; Alizadeh, R; Adeli, R; Mahmoudi, Ali; Semnani, Abbas; Alizadeh, Ramazan; Adeli, Roohollah

    2007-01-01

    A metamaterial with a negative effective index of refraction is made from a three-dimensional hexagonal lattice photonic crystal with a metallic basis embedded in foam. It has been simulated with Ansoft HFSSTM in a frequency range from 7.0 to 12.0 GHz. Simulated results tested experimentally and negative refraction verified in some frequencies. Experimental results are in excellent agreement with simulations.

  4. Effective viscosity of active suspensions: Three-dimensional numerical modeling

    OpenAIRE

    Jibuti, Levan,; Zimmermann, Walter; Rafaï, Salima; Peyla, Philippe

    2014-01-01

    A three-dimensional model is proposed for Chlamydomonas Reinhardtii swimming with a breaststroke-like beating of its two flagella. The model reveals unusual angular orbits of the active swimmer under a linear shear flow. Namely, the swimmer sustains orientation transiently across the flow when flagella plane is perpendicular to the shear plane, and amplify the shear-induced rotation along the flow. Such behavior is a result of the interplay between shear-induced deformation and swimmer's peri...

  5. Isotropic three-dimensional left-handed meta-materials

    OpenAIRE

    Koschny, Th.; Zhang, L; Soukoulis, C. M.

    2005-01-01

    We investigate three-dimensional left-handed and related meta-materials based on a fully symmetric multi-gap single-ring SRR design and crossing continuous wires. We demonstrate isotropic transmission properties of a SRR-only meta-material and the corresponding left-handed material which possesses a negative effective index of refraction due to simultaneously negative effective permeability and permittivity. Minor deviations from complete isotropy are due to the finite thickness of the meta-m...

  6. Index for Three Dimensional Superconformal Field Theories and Its Applications

    International Nuclear Information System (INIS)

    We review aspects of superconformal indices in three dimension. Three dimensional superconformal indices can be exactly computed by using localization method including monopole contribution, and can be applied to provide evidence for mirror duality, AdS4/CFT3 correspondence and global symmetry enhancement of strongly coupled gauge theories. After reviewing, we discuss the possibility of global symmetry enhancement in a finite rank of gauge group.

  7. Matching Three-Dimensional Objects Using a Relational Paradigm

    OpenAIRE

    Shapiro, Linda G.; Moriarty, John D.; Haralick, Robert M.; Mulgaonkar, Prasanna G.

    1980-01-01

    A relational model for describing three-dimensional objects has been designed and implemented as part of a database system. The models which provide rough descriptions to be used at the top level of a hierarchy for describing objects, were designed for initial matching attempts on an unknown object. The descriptions are in terms of the set of simple parts of the objects. Simple parts can be sticks (long, thin parts), plates (flat, wide parts) , and blobs (parts that have three significant dim...

  8. Three-dimensional analysis of tokamaks and stellarators

    OpenAIRE

    Garabedian, Paul R.

    2008-01-01

    The NSTAB equilibrium and stability code and the TRAN Monte Carlo transport code furnish a simple but effective numerical simulation of essential features of present tokamak and stellarator experiments. When the mesh size is comparable to the island width, an accurate radial difference scheme in conservation form captures magnetic islands successfully despite a nested surface hypothesis imposed by the mathematics. Three-dimensional asymmetries in bifurcated numerical solutions of the axially ...

  9. Three-dimensional equilibria in axially symmetric tokamaks

    OpenAIRE

    Garabedian, Paul R.

    2006-01-01

    The NSTAB and TRAN computer codes have been developed to study equilibrium, stability, and transport in fusion plasmas with three-dimensional (3D) geometry. The numerical method that is applied calculates islands in tokamaks like the Doublet III-D at General Atomic and the International Thermonuclear Experimental Reactor. When bifurcated 3D solutions are used in Monte Carlo computations of the energy confinement time, a realistic simulation of transport is obtained. The significance of findin...

  10. The Three-Dimensional Spectrum Analysis of HDTV Luminance Signal

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The international standard for High Definition Television (HDTV) in MPEG- 2 has been established for a few years. Some industrialized modern countries are positively developing HDTV products. However, there are few profound analyses of the HDTV luminance signal' s three-dimensional (3- D) spectrum. The authors make a detailed study of them and sum up the features of the (3-D) HDTV luminance signal' s spectrums and their mathe matical expressions. Based on them, the authors draw their spectral figures.

  11. Multifunctional three-dimensional macroporous nanoelectronic networks for smart materials

    OpenAIRE

    Liu, Jessica C.; Xie, Chong; Dai, Xiaochuan; Jin, Lihua; Wei ZHOU; Lieber, Charles M.

    2013-01-01

    Seamless and minimally-invasive integration of three-dimensional (3D) electronic circuitry within host materials could enable the development of materials systems that are self- monitoring and allow for communication with external environments. Here, we report a general strategy for preparing ordered 3D interconnected and addressable macroporous nanoelectronic networks from ordered two-dimensional (2D) nanowire nanoelectronic “precursors”, which are fabricated by conventional lithography. The...

  12. Three dimensional Green's function for ship motion at forward speed

    Directory of Open Access Journals (Sweden)

    Matiur Rahman

    1990-09-01

    Full Text Available The Green's function formulation for ship motion at forward speed contains double integrals with singularities in the path of integrations with respect to the wave number. In this study, the double integrals have been replaced by single integrals with the use of complex exponential integrals. It has been found that this analysis provides an efficient way of computing the wave resistance for three dimensional potential problem of ship motion with forward speed.

  13. Splitting methods for three-dimensional bio-chemical transport

    OpenAIRE

    Sommeijer, Ben; Kok, Jan

    1996-01-01

    Splitting methods for the time integration of three-dimensional transport-chemistry models offer interesting prospects: second-order accuracy can be combined with sufficient stability, and the amount of implicitness can be reduced to a manageable level. Furthermore, exploiting the parallelization and vectorization features of the algorithm, a realistic simulation with many species over long time intervals becomes feasible. As an alternative to the usual splitting functions, such as co-ordinat...

  14. Three-dimensional metallic photonic crystals with optical bandgaps.

    Science.gov (United States)

    Vasilantonakis, Nikos; Terzaki, Konstantina; Sakellari, Ioanna; Purlys, Vytautas; Gray, David; Soukoulis, Costas M; Vamvakaki, Maria; Kafesaki, Maria; Farsari, Maria

    2012-02-21

    The fabrication of fully three-dimensional photonic crystals with a bandgap at optical wavelengths is demonstrated by way of direct femtosecond laser writing of an organic-inorganic hybrid material with metal-binding moieties, and selective silver coating using electroless plating. The crystals have 600-nm intralayer periodicity and sub-100 nm features, and they exhibit well-defined diffraction patterns. PMID:22278944

  15. Environmental, Transient, Three-Dimensional, Hydrothermal, Mass Transport Code - FLESCOT

    Energy Technology Data Exchange (ETDEWEB)

    Onishi, Yasuo [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Bao, Jie [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Glass, Kevin A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Eyler, L. L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Okumura, Masahiko [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-03-28

    The purpose of the project was to modify and apply the transient, three-dimensional FLESCOT code to be able to effectively simulate cesium behavior in Fukushima lakes/dam reservoirs, river mouths, and coastal areas. The ultimate objective of the FLESCOT simulation is to predict future changes of cesium accumulation in Fukushima area reservoirs and costal water. These evaluation results will assist ongoing and future environmental remediation activities and policies in a systematic and comprehensive manner.

  16. Stem cells in a three-dimensional scaffold environment

    OpenAIRE

    Meng, Xuan; Leslie, Patrick; Zhang, Yanping; Dong, Jiahong

    2014-01-01

    Stem cells have emerged as important players in the generation and maintenance of many tissues. However, the accurate in vitro simulation of the native stem cell niche remains difficult due at least in part to the lack of a comprehensive definition of the critical factors of the stem cell niche based on in vivo models. Three-dimensional (3D) cell culture systems have allowed the development of useful models for investigating stem cell physiology particularly with respect to their ability to s...

  17. Time-Domain Simulation of Three Dimensional Quantum Wires

    Science.gov (United States)

    Mossman, Sean; Kuzyk, Mark G.

    2016-01-01

    A method is presented to calculate the eigenenergies and eigenfunctions of quantum wires. This is a true three-dimensional method based on a direct implementation of the time-dependent Schrödinger equation. It makes no approximations to the Schrödinger equation other than the finite-difference approximation of the space and time derivatives. The accuracy of our method is tested by comparing it to analytical results in a cylindrical wire. PMID:27124603

  18. Three-dimensional conceptual model for service-oriented simulation

    CERN Document Server

    Wang, Wenguang; Zander, Justyna; Zhu, Yifan; 10.1631/jzus.A0920258

    2009-01-01

    In this letter, we propose a novel three-dimensional conceptual model for an emerging service-oriented simulation paradigm. The model can be used as a guideline or an analytic means to find the potential and possible future directions of the current simulation frameworks. In particular, the model inspects the crossover between the disciplines of modeling and simulation, service-orientation, and software/systems engineering. Finally, two specific simulation frameworks are studied as examples.

  19. Epithelial morphogenesis in three-dimensional cell culture system

    OpenAIRE

    Liu, Mengfei; 刘梦菲

    2014-01-01

    In human body, the most common structures formed by epithelial cells are hollow cysts or tubules. The key feature of the cysts and tubules is the central lumen, which is lined by epithelial cell sheets. The central lumen allows material exchange, thus it is indispensable for the proper function of the epithelial tissue. In order to understand the way that the epithelial cells form highly specialized structure, an in vitro three-dimensional (3D) culture system was established. The Caco-2 c...

  20. Three-dimensional stiffness of the carpal arch.

    Science.gov (United States)

    Gabra, Joseph N; Li, Zong-Ming

    2016-01-01

    The carpal arch of the wrist is formed by irregularly shaped carpal bones interconnected by numerous ligaments, resulting in complex structural mechanics. The purpose of this study was to determine the three-dimensional stiffness characteristics of the carpal arch using displacement perturbations. It was hypothesized that the carpal arch would exhibit an anisotropic stiffness behavior with principal directions that are oblique to the conventional anatomical axes. Eight (n=8) cadavers were used in this study. For each specimen, the hamate was fixed to a custom stationary apparatus. An instrumented robot arm applied three-dimensional displacement perturbations to the ridge of trapezium and corresponding reaction forces were collected. The displacement-force data were used to determine a three-dimensional stiffness matrix using least squares fitting. Eigendecomposition of the stiffness matrix was used to identify the magnitudes and directions of the principal stiffness components. The carpal arch structure exhibited anisotropic stiffness behaviors with a maximum principal stiffness of 16.4±4.6N/mm that was significantly larger than the other principal components of 3.1±0.9 and 2.6±0.5N/mm (p<0.001). The principal direction of the maximum stiffness was pronated within the cross section of the carpal tunnel which is accounted for by the stiff transverse ligaments that tightly bind distal carpal arch. The minimal principal stiffness is attributed to the less constraining articulation between the trapezium and scaphoid. This study provides advanced characterization of the wrist׳s three-dimensional structural stiffness for improved insight into wrist biomechanics, stability, and function. PMID:26617368

  1. Three-dimensional topology optimized electrically-small conformal antenna

    DEFF Research Database (Denmark)

    Erentok, Aycan; Sigmund, Ole

    A three-dimensional (3D) conductor-based conformal electrically small antenna is obtained using a topology optimization method. The optimization method distributes a certain amount of conductive material to a designated design domain such that the material layout defines an electrically small rad...... radiator fed by a coaxial cable over a ground plane. Preliminary investigations show that topology optimization method produced a conformal ESA design that has a radiation efficiency of approximately 80% at 300 MHz....

  2. Three-dimensional printable radio frequency identification antennas

    OpenAIRE

    Naushahi, Shayan

    2015-01-01

    In this master’s thesis, radio frequency identification (RFID) systems and three-dimensional (3D) printing technology is studied to determine the possibility of printing electrically small 3D antennas for RFID tags. Computer simulations are carried out to design 3D antennas that are printable with 3D printing processes. Three tag antennas with different geometries are proposed, and they are designed to match to the input impedance of an RFID chip at the Ultra High Frequency (UHF) frequencies....

  3. Four-Dimensional Entropy from Three-Dimensional Gravity.

    Science.gov (United States)

    Carlip, S

    2015-08-14

    At the horizon of a black hole, the action of (3+1)-dimensional loop quantum gravity acquires a boundary term that is formally identical to an action for three-dimensional gravity. I show how to use this correspondence to obtain the entropy of the (3+1)-dimensional black hole from well-understood conformal field theory computations of the entropy in (2+1)-dimensional de Sitter space. PMID:26317707

  4. APPLICATIONS OF FRACTIONAL EXTERIOR DIFFERENTIAL IN THREE-DIMENSIONAL SPACE

    Institute of Scientific and Technical Information of China (English)

    陈勇; 闫振亚; 张鸿庆

    2003-01-01

    A brief survey of fractional calculus and fractional differential forms was firstly given. The fractional exterior transition to curvilinear coordinate at the origin were discussed and the two coordinate transformations for the fractional differentials for three-dimensional Cartesian coordinates to spherical and cylindrical coordinates are obtained, respectively. In particular, for v = m = 1 , the usual exterior transformations, between the spherical coordinate and Cartesian coordinate, as well as the cylindrical coordinate and Cartesian coordinate, are found respectively, from fractional exterior transformation.

  5. Powder blasting for three-dimensional microstructuring of glass

    OpenAIRE

    Belloy, E.; Sayah, A.; Gijs, M. A. M.

    2000-01-01

    We report on powder blasting as a promising technology for the three-dimensional structuring of brittle materials. We investigate the basic parameters of this process, which is based on the erosion of a masked substrate by a high-velocity eroding powder beam, using glass substrates. We study the effect of various parameters on the etching rate, like the powder velocity and the mask feature size, which induces geometrical effects to the erosion process. We introduce oblique powder blasting and...

  6. Three dimensional behaviour of a circular excavation in Nantes, France

    OpenAIRE

    MARTEN, S; Bourgeois, E

    2005-01-01

    In the framework of a co-operation between the LCPC and Solétanche-Bachy, the behaviour of a cicular retaining wall the the site" Ilot 7" in Nantes has been studied. The geometry of the excavation and of the retaining structure is symmetric and the ground conditions show horizontal soil layers. However, the measurements carried out during construction indicate that the deformations of the circular wall are not symmetric at all. Therefore, a three-dimensional finite element calculation (using ...

  7. Three-dimensional topological insulators: A review on host materials

    OpenAIRE

    Feng, Wanxiang; Yao, Yugui

    2012-01-01

    In recent years, three-dimensional topological insulators (3DTI) as a novel state of quantum matter have become a hot topic in the fields of condensed matter physics and materials sciences. To fulfill many spectacularly novel quantum phenomena predicted in 3DTI, real host materials are of crucial importance. In this review paper, we first introduce general methods of searching for new 3DTI based on the density-functional theory. Then, we review the recent progress on materials realization of ...

  8. Three dimensional reconstruction of continuous ICT images by MATLAB

    International Nuclear Information System (INIS)

    The three dimensional (3D) reconstruction of industrial computed tomography (ICT) images plays an important role in non-destructive test (NDT). In this paper, the 3D reconstruction work of a serial of continuous ICT images was done by MATLAB. The reconstructed cubic image was good. The inner structures of the object can be watched by divided and transparently displayed images. And more information of the detected object can be achieved. (authors)

  9. Bilateral bifid mandibular condyles diagnosed with three-dimensional reconstruction

    OpenAIRE

    Tanner, JM; Friedlander, AH; Chang, TI

    2012-01-01

    Bifid mandibular condyles (BMCs) are rare anomalies. The overwhelming majority of prior reports described their predominantly unilateral occurrence diagnosed by panoramic radiography. We present an even rarer case of bilateral BMC initially identified by panoramic radiography and confirmed with colour-enhanced three-dimensional CT. These images substantiate the theory that the secondary condyles arise from the neck of the mandible (Lopez-Lopez et al. Bifid condyle: review of the literature of...

  10. Entropy of three-dimensional BTZ black holes

    Institute of Scientific and Technical Information of China (English)

    GAO; Changjun; SHEN; Yougen

    2004-01-01

    The entropies of scalar field and neutrino field are calculated in the back ground of three-dimensional BTZ black hole.Considering statistical physics,we propose not to consider the superraradiant modes for bosons(Fermion fields do not displaysup perradiance).In fact,the nonsuperradiant modes do contribute exactly the area entropy for both bosons and fermions.The result shows that the neutrino field entropy is 3/2 times the scalar one.

  11. Interlaminar Stress Recovery for Three-Dimensional Finite Elements

    OpenAIRE

    Fagiano, C.; Abdalla, M.M.; Kassapoglou, C.; Gürdal, Z.

    2010-01-01

    Abstract An accurate evaluation of interlaminar stresses in multilayer composite laminates is crucial for the correct prediction of the onset of delamination. In general, three dimensional finite element models are required for acceptable accuracy, especially near free edges and stress concentrations. Interlaminar stresses are continuous both across and along layer interfaces. Nonetheless, the continuity of interlaminar stresses is difficult to enforce in C0 interpolated elements. ...

  12. Unsteady three-dimensional simulation of VTOL upwash fountain turbulence

    Science.gov (United States)

    Childs, Robert E.; Nixon, David

    1987-01-01

    Numerical simulations of a planar turbulent wall jet and a planar VTOL upwash fountain were performed. These are three dimensional simulations which resolve large scale unsteady motions in the flows. The wall jet simulation shows good agreement with experimental data and is presented to verify the simulation methodology. Simulation of the upwash fountain predicts elevated shear stress and a half velocity width spreading rate of 33% which agrees well with experiment. Turbulence mechanisms which contribute to the enhanced spreading rate are examined.

  13. Three-dimensional conceptual model for service-oriented simulation

    Institute of Scientific and Technical Information of China (English)

    Wen-guang WANG; Wei-ping WANG; Justyna ZANDER; Yi-fan ZHU

    2009-01-01

    In this letter, we propose a novel three-dimensional conceptual model for an emerging service-oriented simulation paradigm. The model can be used as a guideline or an analytic means to find the potential and possible future directions of the current simulation frameworks, In particular, the model inspects the crossover between the disciplines of modeling and simulation,service-orientation, and software/systems engineering. Finally, two specific simulation frameworks are studied as examples.

  14. Three-Dimensional Simulations of Deep-Water Breaking Waves

    CERN Document Server

    Brucker, Kyle A; Dommermuth, Douglas G; Adams, Paul

    2014-01-01

    The formulation of a canonical deep-water breaking wave problem is introduced, and the results of a set of three-dimensional numerical simulations for deep-water breaking waves are presented. In this paper fully nonlinear progressive waves are generated by applying a normal stress to the free surface. Precise control of the forcing allows for a systematic study of four types of deep-water breaking waves, characterized herein as weak plunging, plunging, strong plunging, and very strong plunging.

  15. Three-dimensional geometric morphometrics for studying floral shape variation

    OpenAIRE

    Van der Niet, T; Zollikofer, C P E; Ponce de León, M S; Johnson, S D; H. P. Linder

    2010-01-01

    Variation in floral shape is of major interest to evolutionary and pollination biologists, plant systematists and developmental geneticists. Quantifying this variation has been difficult due to the three-dimensional (3D) complexity of angiosperm flowers. By combining 3D geometric representations of flowers obtained by micro-computed tomography scanning with geometric morphometric methods, well established in zoology and anthropology, floral shape variation can be analyzed quantitatively, allo...

  16. Three-Dimensional Magnetic Assembly of Microscale Hydrogels

    OpenAIRE

    Feng XU; Wu, Chung-an Max; Rengarajan, Venkatakrishnan; Finley, Thomas Dylan; Keles, Hasan Onur; Sung, Yuree; Li, Baoqiang; Gurkan, Umut Atakan; Demirci, Utkan

    2011-01-01

    Directed assembly of nano and microscale particles is of great interest and has widespread applications in various fields including electronics, nanomaterials and tissue engineering. Bottom-up tissue engineering is motivated by the occurrence of repeating functional units in vivo. The bottom-up approach requires novel techniques to assemble engineered functional units as building blocks at a high speed with spatial control over three-dimensional (3D) micro-architecture. Here, we report a magn...

  17. Three-dimensional CT of the pediatric spine

    International Nuclear Information System (INIS)

    CT of the spine has been shown to be useful in evaluating congenital, neoplastic, inflammatory, and traumatic lesions. Any portion of the neural arch may be involved by these disease processes. The complex nature of the spinal column can make evaluation of these abnormalities difficult on axial CT. This is especially true if the spine is distorted by scoliosis, kyphosis, or lordosis. This exhibit illustrates the advantages and drawbacks of three-dimensional CT reconstructed images of spinal abnormalities in children

  18. Athermally photoreduced graphene oxides for three-dimensional holographic images

    OpenAIRE

    Li, Xiangping; Ren, Haoran; Chen, Xi; LIU, JUAN; Li, Qin; Li, Chengmingyue; Xue, Gaolei; Jia, Jia; Cao, Liangcai; Sahu, Amit; Hu, Bin; Wang, Yongtian; Jin, Guofan; Gu, Min

    2015-01-01

    The emerging graphene-based material, an atomic layer of aromatic carbon atoms with exceptional electronic and optical properties, has offered unprecedented prospects for developing flat two-dimensional displaying systems. Here, we show that reduced graphene oxide enabled write-once holograms for wide-angle and full-colour three-dimensional images. This is achieved through the discovery of subwavelength-scale multilevel optical index modulation of athermally reduced graphene oxides by a singl...

  19. Three dimensional electromagnetic wavepackets in a plasma: Spatiotemporal modulational instability

    Energy Technology Data Exchange (ETDEWEB)

    Borhanian, J.; Hosseini Faradonbe, F. [Department of Physics, Faculty of Science, University of Mohaghegh Ardabili, P. O. Box 179, Ardabil (Iran, Islamic Republic of)

    2014-04-15

    The nonlinear interaction of an intense electromagnetic beam with relativistic collisionless unmagnetized plasma is investigated by invoking the reductive perturbation technique, resting on the model of three-dimensional nonlinear Schrödinger (NLS) equation with cubic nonlinearity which incorporates the effects of self-focusing, self-phase modulation, and diffraction on wave propagation. Relying on the derived NLS equation, the occurrence of spatiotemporal modulational instability is investigated in detail.

  20. Simulating Photons and Plasmons in a Three-dimensional Lattice

    International Nuclear Information System (INIS)

    Three-dimensional metallic photonic structures are studied using a newly developed mixed finite element-finite difference (FE-FD) code, Curly3d. The code solves the vector Helmholtz equation as an eigenvalue problem in the unit cell of a triply periodic lattice composed of conductors and/or dielectrics. The mixed FE-FD discretization scheme ensures rapid numerical convergence of the eigenvalue and allows the code to run at low resolution. Plasmon and photonic band structure calculations are presented

  1. Compression of encrypted three-dimensional objects using digital holography

    OpenAIRE

    Naughton, Thomas J.; Javidi, Bahram

    2004-01-01

    We present the results of applying data compression techniques to encrypted three-dimensional objects. The objects are captured using phase-shift digital holography and encrypted using a random phase mask in the Fresnel domain. Lossy quantization is combined with lossless coding techniques to quantify compression ratios. Lossless compression alone applied to the encrypted holographic data achieves compression ratios lower than 1.05. When combined with quantization and an integer encoding s...

  2. The three-dimensional origin of the classifying algebra

    OpenAIRE

    Fuchs, Jurgen; Schweigert, Christoph; Stigner, Carl

    2009-01-01

    It is known that reflection coefficients for bulk fields of a rational conformal field theory in the presence of an elementary boundary condition can be obtained as representation matrices of irreducible representations of the classifying algebra, a semisimple commutative associative complex algebra. We show how this algebra arises naturally from the three-dimensional geometry of factorization of correlators of bulk fields on the disk. This allows us to derive explicit expressions for the str...

  3. Continuum limit of amorphous elastic bodies (III): Three dimensional systems

    OpenAIRE

    Léonforte, F.; Boissière, R.; Tanguy, Arnaud; Wittmer, J.P.; Barrat, J. -L.

    2005-01-01

    Extending recent numerical studies on two dimensional amorphous bodies, we characterize the approach of elastic continuum limit in three dimensional (weakly polydisperse) Lennard-Jones systems. While performing a systematic finite-size analysis (for two different quench protocols) we investigate the non-affine displacement field under external strain, the linear response to an external delta force and the low-frequency harmonic eigenmodes and their density distribution. Qualitatively similar ...

  4. Three-Dimensional Biomechanical Analysis of the Bovine Humerus

    OpenAIRE

    Bouza-Rodríguez, José Benito; Miramontes-Sequeiros, Luz Calia

    2014-01-01

    There are few reports on the biomechanical analysis of the animal humerus. In this study, a three-dimensional finite element model of the bovine humerus was created, and loaded with the physiological forces acting when the cow is falling or jumping (weight and impact forces). Subsequently the corresponding stress and strain distribution in the humerus for different inclined positions of bone was determined.The highest stress concentration occurred in the distal humeral diaphysis, both when on...

  5. Three-dimensional discrete ordinates reactor assembly calculations on GPUs

    Energy Technology Data Exchange (ETDEWEB)

    Evans, Thomas M [ORNL; Joubert, Wayne [ORNL; Hamilton, Steven P [ORNL; Johnson, Seth R [ORNL; Turner, John A [ORNL; Davidson, Gregory G [ORNL; Pandya, Tara M [ORNL

    2015-01-01

    In this paper we describe and demonstrate a discrete ordinates sweep algorithm on GPUs. This sweep algorithm is nested within a multilevel comunication-based decomposition based on energy. We demonstrated the effectiveness of this algorithm on detailed three-dimensional critical experiments and PWR lattice problems. For these problems we show improvement factors of 4 6 over conventional communication-based, CPU-only sweeps. These sweep kernel speedups resulted in a factor of 2 total time-to-solution improvement.

  6. Nanohydration of uracil: emergence of three-dimensional structures and proton-induced charge transfer.

    Science.gov (United States)

    Bacchus-Montabonel, Marie-Christine; Calvo, Florent

    2015-04-21

    Stepwise hydration of uracil has been theoretically revisited using different methods ranging from classical force fields to quantum chemical approaches. Hydration initially begins within the uracil plane but proceeds at four molecules into three-dimensional configurations or even water clusters next to the nucleobase. The relative stability between the various structures is significantly affected by zero-point energy and finite temperature (entropy) effects and also gives rise to markedly different responses to an excitation by an impinging high-energy proton. In particular, charge transfer to the molecular complex is dramatically altered in collisions toward the coating cluster but barely modified for peripheral hydration patterns. PMID:25793649

  7. Surface image of herniated disc on three-dimensional CT

    International Nuclear Information System (INIS)

    To evaluate surface configuration of herniated disc on three-dimensional CT. Three dimensional surface images reconstructed from CT scans(1 mm thick) of 24 surgically confirmed herniated discs in 23 patients were reviewed. Disc surface was classified into peripheral and central zones in contact with consecutive peripheral ring and central endplate. Surface irregularity was categorized into two types(local and general). The incidence, size, and extent of local irregularity were observed. General irregularity incidence and severity ranges in 4 grades, and peripheral width were evaluated. The findings were correlated with discography. Local irregularity compatible with anulus tear in discography was shown in all. It was large(13/24) and mainly peripheral tract extending to disc margin in protrusion(3/5) and sequestration(5/7), and cleft encompassing central zone to disc margin in extrusion(9/12). General irregularity was predominantly grade 3(15/22) and was shown in all except in 2 protrusions. Peripheral width was 0.56 of central radius. Extrusion in herniated disc shows characteristic cleft encompassing central zone to disc margin whereas sequestration or protrusion displays tract extending from peripheral zone to disc margin. Thus, three dimensional surface imaging may aid the diagnosis, follow-up, prediction, and treatment of herniated disc

  8. Three-dimensional magnetic recording using ferromagnetic resonance

    Science.gov (United States)

    Suto, Hirofumi; Kudo, Kiwamu; Nagasawa, Tazumi; Kanao, Taro; Mizushima, Koichi; Sato, Rie

    2016-07-01

    To meet the ever-increasing demand for data storage, future magnetic recording devices will need to be made three-dimensional by implementing multilayer recording. In this article, we present methods of detecting and manipulating the magnetization direction of a specific layer selectively in a vertically stacked multilayer magnetic system, which enable layer-selective read and write operations in three-dimensional magnetic recording devices. The principle behind the methods is ferromagnetic resonance excitation in a microwave magnetic field. By designing each magnetic recording layer to have a different ferromagnetic resonance frequency, magnetization excitation can be induced individually in each layer by tuning the frequency of an applied microwave magnetic field, and this selective magnetization excitation can be utilized for the layer-selective operations. Regarding media for three-dimensional recording, when layers of a perpendicular magnetic material are vertically stacked, dipolar interaction between multiple recording layers arises and is expected to cause problems, such as degradation of thermal stability and switching field distribution. To solve these problems, we propose the use of an antiferromagnetically coupled structure consisting of hard and soft magnetic layers. Because the stray fields from these two layers cancel each other, antiferromagnetically coupled media can reduce the dipolar interaction.

  9. Three-dimensional dynamic MR hysterosalpingography: a preliminary report

    International Nuclear Information System (INIS)

    The aim of this study was to evaluate the feasibility of three-dimensional dynamic MR hysterosalpingography (3D MR HSG) for visualization of the cavum uteri and demonstration of bilateral fallopian tube patency as an alternative to conventional hysterosalpingography. Five infertile female patients underwent 3D dynamic MR HSG prior to conventional hysterosalpingography. The MR protocol consisted of axial T1-weighted spin-echo (SE), axial/coronal T2-weighted fast SE (FSE), and 3D MR angiography sequences before, during, and after injection of a diluted gadolinium solution into the cavum uteri via a balloon catheter. Positioning of the catheter was feasible in all patients. In one patient the catheter slipped out during MRI and in one patient the catheter was placed far in the cavum uteri. In three patients catheter position was optimal at the level of the cervical canal. Evaluation of pelvic anatomy, myometrium, and ovaries was possible in all patients on the basis of T1-weighted SE and T2-weighted FSE. Three-dimensional visualization of the dilated cavum uteri was possible in four patients. In these four patients 3D MR HSG also proved bilateral fallopian tube patency which was confirmed in each patient by conventional hysterosalpingography. Three-dimensional MR HSG is feasible and further research should be done to determine if this technique can evolve into an alternative technique to conventional hysterosalpingography with the advantages of no radiation and additional visualization of the uterus wall and ovaries. (orig.)

  10. Surface image of herniated disc on three-dimensional CT

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Kyung Il; Jeon, Chang Hoon; Kim, Sun Yong; Kim, Ok Hwa; Suh, Jung Ho [Ajou Univ. College of Medicine, Suwon(Korea, Republic of)

    1996-03-01

    To evaluate surface configuration of herniated disc on three-dimensional CT. Three dimensional surface images reconstructed from CT scans(1 mm thick) of 24 surgically confirmed herniated discs in 23 patients were reviewed. Disc surface was classified into peripheral and central zones in contact with consecutive peripheral ring and central endplate. Surface irregularity was categorized into two types(local and general). The incidence, size, and extent of local irregularity were observed. General irregularity incidence and severity ranges in 4 grades, and peripheral width were evaluated. The findings were correlated with discography. Local irregularity compatible with anulus tear in discography was shown in all. It was large(13/24) and mainly peripheral tract extending to disc margin in protrusion(3/5) and sequestration(5/7), and cleft encompassing central zone to disc margin in extrusion(9/12). General irregularity was predominantly grade 3(15/22) and was shown in all except in 2 protrusions. Peripheral width was 0.56 of central radius. Extrusion in herniated disc shows characteristic cleft encompassing central zone to disc margin whereas sequestration or protrusion displays tract extending from peripheral zone to disc margin. Thus, three dimensional surface imaging may aid the diagnosis, follow-up, prediction, and treatment of herniated disc.

  11. Nonlinear three-dimensional trajectory following: simulation and application

    Science.gov (United States)

    Hines, George H.

    In light of recent military requirements for unmanned and autonomous vehicles, research into methods of designing arbitrary three-dimensional trajectories and controlling aircraft along them has become vital. In this report, we explore two methods of nonlinear control for the purpose of following three-dimensional trajectories and paths. First, prior work on a dynamic feedback linearization exploiting the differential flatness of the ideal airplane is adapted with the intent of implementing it on a physical testbed in MIT's Realtime indoor Autonomous Vehicle test ENvironment (RAVEN), but poor behavior—both in simulation and in hardware—under moderate levels of joint parameter uncertainty thwarted attempts at implementation. Additionally, the differential flatness technique in its pure form follows trajectories, which are sometimes inferior intuitively and practically to paths. In the context of unmanned air vehicle (UAV) flight in gusty environments, this motivated the extension of prior work on two-dimensional path following to three-dimensions, and simulations are presented in which the fully nonlinear controller derived from differential flatness follows a trajectory that is generated dynamically from a path. The three-dimensional path-following logic is actually implemented in RAVEN, and results are presented that demonstrate good vertical rise time in response to a step input and centimeter accuracy in vertical and lateral tracking. Future directions are proposed.

  12. Interaction of two three-dimensional explosion bubbles

    Institute of Scientific and Technical Information of China (English)

    YAO Xiong-liang; ZHANG A-man; LIU Yu-chen

    2007-01-01

    The interaction of two underwater explosion bubbles was mathematically analyzed in this paper. Based on the assumption of potential flow, high-order curved elements were used to discretize the boundary integral equation and solve it. Assuming that gas inside the bubble follows the isentropic rule,the Euler-Lagrange method was used to trace the evolution of the bubble, and when calculating the singular integral, the singularity of the double-layer singular integral was eliminated by reconstructing a principal-value integral of double-layer potential so that a more precise result could be obtained. Elastic mesh technique (EMT) was also used when tracing the evolution of the bubble interface, and numerical smoothing wasn't needed. A comparison of calculations using this three-dimensional model with results of the Reyleigh-Plesset bubble model shows that the three-dimensional model and calculation method in this paper is practical. This three-dimensional model was applied to simulate the interaction of two bubbles under the action of gravity, and the dynamic characteristics of two bubbles near the surface was also analyzed. Bubbles influenced by surface effects and gravity present severe non-linearity. This paper provides a reference for research into the dynamics of multi-bubbles.

  13. Three-dimensional fluorescence characteristics of white chrysanthemum flowers

    Science.gov (United States)

    Fan, Yunchang; Li, Yang; Cai, Hongxin; Li, Jing; Miao, Juan; Fu, Dexue; Su, Kun

    2014-09-01

    White chrysanthemum flower is one of the most popular plants found everywhere in China and used as herbs. In the present work, three-dimensional fluorescence technique was used to discriminate species of white chrysanthemum flowers. Parameters affecting extraction efficiency were investigated. Under the optimal conditions, the three-dimensional fluorescence characteristics of three types of white chrysanthemum flowers were obtained. It was found that there were two main fluorescence peaks with remarkable difference in fluorescence intensity, one was corresponding to flavonoids and another was attributed to chlorophyll-like compounds. There were remarkable differences among the contours of the three white chrysanthemum flowers. Further studies showed that the fluorescence intensity ratios of chlorophyll-like compounds to flavonoids had a certain relationship with the species; those for Huai, Hang and Huangshan white chrysanthemum flowers were 6.9-7.4, 18.9-21.4 and 73.6-84.5, respectively. All of the results suggest that three-dimensional fluorescence spectra can be used for the discrimination of white chrysanthemum flowers with the advantages of low cost, ease for operation and intuition.

  14. Three-dimensional Morphological Analysis for Geological Bodies and Application

    Directory of Open Access Journals (Sweden)

    Yanhong Zou

    2011-06-01

    Full Text Available To address the spatial Morphological analysis of complex geological bodies in stereoscopic quantitative prediction of concealed ore bodies, a three-dimensional morphological analysis method for geological bodies based on 3-dimensional raster model under visualization environment was put forward by combining mathematical morphology with Euclidean distance transform theory. Firstly, the 3-dimensional visualization models for geological bodies were constructed on the basis of the 3-dimensional geological modeling (3DGM technology; Secondly, the algorithm for extracting the surface shape trend of geological body with the 3-dimensional raster model was proposed by using mathematical morphology filtering. By the combination of morphological filtering, global set operation and three-dimensional Euclidean distance transform, the models for the quantitative analysis and hierarchical extraction of the shape undulance were established. Lastly, as a case study, the three-dimensional morphological analysis method was applied in analyzing quantitatively the Xinwuli magmatic body in Fenghuangshan ore field in Tongling, Anhui Province. By means of the calculation model of Euclidean distance field, the quantitative extraction of the shape trend and shape undulance as well as the angle between geological interface and trend surface, as the quantitative indexes of geological ore-controlling factors, were achieved after building the 3D raster models of the magmatic body. The results show that the morphological analysis method is feasible to calculate various morphological parameters of complex geological bodies and extract quantitative indexes of geological ore-controlling factors successfully for stereoscopic quantitative predication of concealed ore bodies.

  15. Three dimensional self-assembly at the nanoscale

    Science.gov (United States)

    Gracias, D. H.

    2013-05-01

    At the nanoscale, three dimensional manipulation and assembly becomes extremely challenging and also cost prohibitive. Self-assembly provides an attractive and possibly the only highly parallel methodology to structure truly three dimensional patterned materials and devices at this size scale for applications in electronics, optics, robotics and medicine. This is a concise review along with a perspective of an important and exciting field in nanotechnology and is related to a Nanoengineering Pioneer Award that I received at this SPIE symposium for my contributions to the 3D selfassembly of nanostructures. I detail a historical account of 3D self-assembly and outline important developments in this area which is put into context with the larger research areas of 3D nanofabrication, assembly and nanomanufacturing. A focus in this review is on our work as it relates to the self-assembly with lithographically patterned units; this approach provides a means for heterogeneous integration of periodic, curved and angled nanostructures with precisely defined three dimensional patterns.

  16. Numerical simulation of three-dimensional gas detonation

    International Nuclear Information System (INIS)

    We investigate the characteristics of the three-dimensional detonation in an argon-diluted mixture of hydrogen and oxygen. The three-dimensional Euler equations with a simple chemical reaction model are used as the governing equations for the detonation problem. The spatial derivatives are evaluated using the WENO scheme, and the temporal derivative is calculated using the TVD Runge-Kutta method. It is verified that the detonation front is composed of incident shocks and Mach stems, joined at the lines of triple points by transverse waves. And the clear cellular structure is displayed by using a three-dimensional numerical visualization. The process of generating unburned gas pockets is shown by the spatial isosurface profiles of the reaction progress parameter in the exothermic period, and it is explained that the triple lines play a role of 'shutter'. Furthermore, the rectangles, enclosed by the triple lines, vary with the movement of the triple lines. Consequently, the evolution between the diagonal detonation and the rectangular detonation is realized

  17. Performance of different three-dimensional scaffolds for in vivo endochondral bone generation

    Directory of Open Access Journals (Sweden)

    W Yang

    2014-06-01

    Full Text Available In the context of skeletal tissue development and repair, endochondral ossification has inspired a new approach to regenerate bone tissue in vivo using a cartilage intermediate as an osteoinductive template. The aim of this study was to investigate the behavior of mesenchymal stem cells (MSCs in regard to in vitro cartilage formation and in vivo bone regeneration when combined with different three-dimensional (3D scaffold materials, i.e., hydroxyapatite/tricalcium phosphate (HA/TCP composite block, polyurethane (PU foam, poly(lactic-co-glycolic acid/poly(ε-caprolactone electrospun fibers (PLGA/PCL and collagen I gel. To this end, rat MSCs were seeded on these scaffolds and chondrogenically differentiated in vitro for 4 weeks followed by in vivo subcutaneous implantation for 8 weeks. Nonetheless, the quality and maturity of in vivo ectopic bone formation appeared to be scaffold/material-dependent. Eight weeks of implantation was not sufficient to ossify the entire PLGA/PCL constructs, albeit a comprehensive remodeling of the cartilage had occurred. For HA/TCP, PU and collagen I scaffolds, more mature bone formation with rich vascularity and marrow stroma development could be observed. These data suggest that chondrogenic priming of MSCs in the presence of different scaffold materials allows the establishment of reliable templates for generating functional endochondral bone tissue in vivo without using osteoinductive growth factors. The morphology and maturity of bone formation.

  18. Multi-layered culture of human skin fibroblasts and keratinocytes through three-dimensional freeform fabrication.

    Science.gov (United States)

    Lee, Wonhye; Debasitis, Jason Cushing; Lee, Vivian Kim; Lee, Jong-Hwan; Fischer, Krisztina; Edminster, Karl; Park, Je-Kyun; Yoo, Seung-Schik

    2009-03-01

    We present a method to create multi-layered engineered tissue composites consisting of human skin fibroblasts and keratinocytes which mimic skin layers. Three-dimensional (3D) freeform fabrication (FF) technique, based on direct cell dispensing, was implemented using a robotic platform that prints collagen hydrogel precursor, fibroblasts and keratinocytes. A printed layer of cell-containing collagen was crosslinked by coating the layer with nebulized aqueous sodium bicarbonate. The process was repeated in layer-by-layer fashion on a planar tissue culture dish, resulting in two distinct cell layers of inner fibroblasts and outer keratinocytes. In order to demonstrate the ability to print and culture multi-layered cell-hydrogel composites on a non-planar surface for potential applications including skin wound repair, the technique was tested on a poly(dimethylsiloxane) (PDMS) mold with 3D surface contours as a target substrate. Highly viable proliferation of each cell layer was observed on both planar and non-planar surfaces. Our results suggest that organotypic skin tissue culture is feasible using on-demand cell printing technique with future potential application in creating skin grafts tailored for wound shape or artificial tissue assay for disease modeling and drug testing. PMID:19108884

  19. Ultrastructural changes following electron irradiation in three-dimensional culture of normal human dermal fibroblasts

    International Nuclear Information System (INIS)

    The present study was designed to examine the effect of electron irradiation on fibroblasts and extracellular matrices electron-microscopically. The three-dimensional dermal fibroblast culture was exposed to one, 4 or 10 Gy of electron beams. One day after irradiation, fibroblasts were vacuolated in all irradiated groups and intercellular spaces were increased in a dose-dependent manner. Seven days later, intercellular spaces became dense in both one and 4 Gy groups, although they were still extremely increased in the 10 Gy group. The remaining fibroblasts were still activated in all groups. Thirty days after irradiation, myofibroblastic cells were scarcely observed, but extracellular fine fibrils and collagen fibrils were observed in all irradiated groups. The other ultrastructural findings were similar to those in the control group. In conclusion, electron beams damaged not only cells but also extracellular matrix. The extracellular matrix may be repaired by activated residual fibroblasts, resulting in the mixture of new and old collagen fibrils having different diamters. (N.K.)

  20. A bioactive hybrid three-dimensional tissue-engineering construct for cartilage repair.

    Science.gov (United States)

    Ainola, Mari; Tomaszewski, Waclaw; Ostrowska, Barbara; Wesolowska, Ewa; Wagner, H Daniel; Swieszkowski, Wojciech; Sillat, Tarvo; Peltola, Emilia; Konttinen, Yrjö T

    2016-01-01

    The aim was to develop a hybrid three-dimensional-tissue engineering construct for chondrogenesis. The hypothesis was that they support chondrogenesis. A biodegradable, highly porous polycaprolactone-grate was produced by solid freeform fabrication. The polycaprolactone support was coated with a chitosan/polyethylene oxide nanofibre sheet produced by electrospinning. Transforming growth factor-β3-induced chondrogenesis was followed using the following markers: sex determining region Y/-box 9, runt-related transcription factor 2 and collagen II and X in quantitative real-time polymerase chain reaction, histology and immunostaining. A polycaprolactone-grate and an optimized chitosan/polyethylene oxide nanofibre sheet supported cellular aggregation, chondrogenesis and matrix formation. In tissue engineering constructs, the sheets were seeded first with mesenchymal stem cells and then piled up according to the lasagne principle. The advantages of such a construct are (1) the cells do not need to migrate to the tissue engineering construct and therefore pore size and interconnectivity problems are omitted and (2) the cell-tight nanofibre sheet and collagen-fibre network mimic a cell culture platform for mesenchymal stem cells/chondrocytes (preventing escape) and hinders in-growth of fibroblasts and fibrous scarring (preventing capture). This allows time for the slowly progressing, multiphase true cartilage regeneration. PMID:26341661

  1. Characterization of the migration of lung and blood T cells in response CXCL12 in a three-dimensional matrix

    OpenAIRE

    Day, Caroline E; Guillen, Cristina; Willars, Gary B.; Wardlaw, Andrew J.

    2010-01-01

    The ability of T cells to microlocalize within tissues, such as the lung, is crucial for immune surveillance and increased T-cell infiltration is a feature of many inflammatory lung conditions. T-cell migration has mainly been studied in two-dimensional assays. Using three-dimensional collagen gels to mimic the extracellular matrix of lung tissue, we have characterized the migration of T lymphocytes isolated from peripheral blood (PBT) and lung (LT) in response to interleukin-2 (IL-2) and CXC...

  2. Exploring a role in tanning for the gap region of the collagen fibril

    Science.gov (United States)

    Three-dimensional structures of fibrillar collagens have been the subject of numerous studies for more than 60 years. Electron micrographs of stained collagen fibrils display a pattern of alternating light and dark bands perpendicular to the axis of the collagen fibril. Light bands correspond to r...

  3. Three-dimensional culture of human meniscal cells: Extracellular matrix and proteoglycan production

    Directory of Open Access Journals (Sweden)

    Norton H James

    2008-06-01

    Full Text Available Abstract Background The meniscus is a complex tissue whose cell biology has only recently begun to be explored. Published models rely upon initial culture in the presence of added growth factors. The aim of this study was to test a three-dimensional (3D collagen sponge microenvironment (without added growth factors for its ability to provide a microenvironment supportive for meniscal cell extracellular matrix (ECM production, and to test the responsiveness of cells cultured in this manner to transforming growth factor-β (TGF-β. Methods Experimental studies were approved prospectively by the authors' Human Subjects Institutional Review Board. Human meniscal cells were isolated from surgical specimens, established in monolayer culture, seeded into a 3D scaffold, and cell morphology and extracellular matrix components (ECM evaluated either under control condition or with addition of TGF-β. Outcome variables were evaluation of cultured cell morphology, quantitative measurement of total sulfated proteoglycan production, and immunohistochemical study of the ECM components chondroitin sulfate, keratan sulfate, and types I and II collagen. Result and Conclusion Meniscal cells attached well within the 3D microenvironment and expanded with culture time. The 3D microenvironment was permissive for production of chondroitin sulfate, types I and II collagen, and to a lesser degree keratan sulfate. This microenvironment was also permissive for growth factor responsiveness, as indicated by a significant increase in proteoglycan production when cells were exposed to TGF-β (2.48 μg/ml ± 1.00, mean ± S.D., vs control levels of 1.58 ± 0.79, p

  4. Three-dimensional appearance of the lips muscles with three-dimensional isotropic MRI: in vivo study

    Energy Technology Data Exchange (ETDEWEB)

    Olszewski, Raphael; Reychler, H. [Universite Catholique de Louvain, Department of Oral and Maxillofacial Surgery, Cliniques Universitaires Saint Luc, Brussels (Belgium); Liu, Y.; Xu, T.M. [Peking University School and Hospital of Stomatology, Department of Orthodontics, Beijing (China); Duprez, T. [Universite Catholique de Louvain, Department of Radiology, Cliniques Universitaires Saint Luc, Brussels (Belgium)

    2009-06-15

    Our knowledge of facial muscles is based primarily on atlases and cadaveric studies. This study describes a non-invasive in vivo method (3D MRI) for segmenting and reconstructing facial muscles in a three-dimensional fashion. Three-dimensional (3D), T1-weighted, 3 Tesla, isotropic MRI was applied to a subject. One observer performed semi-automatic segmentation using the Editor module from the 3D Slicer software (Harvard Medical School, Boston, MA, USA), version 3.2. We were able to successfully outline and three-dimensionally reconstruct the following facial muscles: pars labialis orbicularis oris, m. levatro labii superioris alaeque nasi, m. levator labii superioris, m. zygomaticus major and minor, m. depressor anguli oris, m. depressor labii inferioris, m. mentalis, m. buccinator, and m. orbicularis oculi. 3D reconstruction of the lip muscles should be taken into consideration in order to improve the accuracy and individualization of existing 3D facial soft tissue models. More studies are needed to further develop efficient methods for segmentation in this field. (orig.)

  5. Three-dimensional lithographically-defined organotypic tissue arrays for quantitative analysis of morphogenesis and neoplastic progression

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, Celeste M.; Inman, Jamie L.; Bissell, Mina J.

    2008-02-13

    Here we describe a simple micromolding method to construct three-dimensional arrays of organotypic epithelial tissue structures that approximate in vivo histology. An elastomeric stamp containing an array of posts of defined geometry and spacing is used to mold microscale cavities into the surface of type I collagen gels. Epithelial cells are seeded into the cavities and covered with a second layer of collagen. The cells reorganize into hollow tissues corresponding to the geometry of the cavities. Patterned tissue arrays can be produced in 3-4 h and will undergo morphogenesis over the following one to three days. The protocol can easily be adapted to study a variety of tissues and aspects of normal and neoplastic development.

  6. A Novel Three-Dimensional Wound Healing Model

    Directory of Open Access Journals (Sweden)

    Zhuo J. Chen

    2014-12-01

    Full Text Available Wound healing is a well-orchestrated process, with various cells and growth factors coming into the wound bed at a specific time to influence the healing. Understanding the wound healing process is essential to generating wound healing products that help with hard-to-heal acute wounds and chronic wounds. The 2D scratch assay whereby a wound is created by scratching a confluent layer of cells on a 2D substrate is well established and used extensively but it has a major limitation—it lacks the complexity of the 3D wound healing environment. Established 3D wound healing models also have many limitations. In this paper, we present a novel 3D wound healing model that closely mimics the skin wound environment to study the cell migration of fibroblasts and keratinocytes. Three major components that exist in the wound environment are introduced in this new model: collagen, fibrin, and human foreskin fibroblasts. The novel 3D model consists of a defect, representing the actual wound, created by using a biopsy punch in a 3D collagen construct. The defect is then filled with collagen or with various solutions of fibrinogen and thrombin that polymerize into a 3D fibrin clot. Fibroblasts are then added on top of the collagen and their migration into the fibrin—or collagen—filled defect is followed for nine days. Our data clearly shows that fibroblasts migrate on both collagen and fibrin defects, though slightly faster on collagen defects than on fibrin defects. This paper shows the visibility of the model by introducing a defect filled with fibrin in a 3D collagen construct, thus mimicking a wound. Ongoing work examines keratinocyte migration on the defects of a 3D construct, which consists of collagen-containing fibroblasts. The model is also used to determine the effects of various growth factors, delivered in the wound defects, on fibroblasts’ and keratinocytes’ migration into the defects. Thus this novel 3D wound healing model provides a more

  7. Potential of Raloxifene in reversing osteoarthritis-like alterations in rat chondrocytes: An in vitro model study

    Indian Academy of Sciences (India)

    Aysegul Kavas; Seda Tuncay Cagatay; Sreeparna Banerjee; Dilek Keskin; Aysen Tezcaner

    2013-03-01

    The aim of this study was to investigate the effects of Raloxifene (Ral) on degeneration-related changes in osteoarthritis (OA)-like chondrocytes using two- and three-dimensional models. Five-azacytidine (Aza-C) was used to induce OA-like alterations in rat articular chondrocytes and the model was verified at molecular and macrolevels. Chondrocytes were treated with Ral (1, 5 and 10 M) for 10 days. Caspase-3 activity, gene expressions of aggrecan, collagen II, alkaline phosphatase (ALP), collagen X, matrix metalloproteinases (MMP-13, MMP-3 and MMP-2), and MMP-13, MMP-3 and MMP-2 protein expressions were studied in two-dimensional model. Matrix deposition and mechanical properties of agarose-chondrocyte discs were evaluated in three-dimensional model. One M Ral reduced expression of OA-related genes, decreased apoptosis, and MMP-13 and MMP-3 protein expressions. It also increased aggrecan and collagen II gene expressions relative to untreated OA-like chondrocytes. In three-dimensional model, 1 M Ral treatment resulted in increased collagen deposition and improved mechanical properties, although a significant increase for sGAG was not observed. In summation, 1 M Ral improved matrix-related activities, whereas dose increment reversed these effects except ALP gene expression and sGAG deposition. These results provide evidence that low-dose Ral has the potential to cease or reduce the matrix degeneration in OA.

  8. Three-dimensional stochastic seepage field for embankment engineering

    Institute of Scientific and Technical Information of China (English)

    Ya-jun WANG; Wo-hua ZHANG; Chang-yu WU; Da-chun REN

    2009-01-01

    Owing to the complexity of get-engineering seepage problems influenced by different random factors, three-dimensional simulation and analysis of the stochastic seepage field plays an important role in engineering applications. A three-dimensional anisotropic heterogeneous steady random seepage model was developed on the basis of the finite element method. A statistical analysis of the distribution characteristics of soil parameters sampled from the main embankment of the Yangtze River in the Southern Jingzhou zone of China was conducted. The Kolomogorov-Smimov test verified the statistical hypothesis that the permeability coefficient tensor has a Gaussian distribution. With the help of numerical analysis of the stochastic seepage field using the developed model, various statistical and random characteristics of the stochastic seepage field of the main embankment of the Yangtze River in the Southern Jingzhou zone of China were investigated. The model was also examined with statistical testing. Through the introduction of random variation of the upstream and downstream water levels into the model, the effects of the boundary randomness due to variation of the downstream and upstream water levels on the variation of simulated results presented with a vector series of the random seepage field were analyzed. Furthermore, the combined influence of the variation of the soil permeability coefficient and such seepage resistance measures as the cut-off wall and relief ditch on the hydraulic head distribution was analyzed and compared with the results obtained by determinate analysis. Meanwhile, sensitivities of the hydraulic gradient and downstream exit height to the variation of boundary water level were studied. The validity of the simulated results was verified by stochastic testing and measured data. The developed model provides more detail and a full stochastic algorithm to characterize and analyze three-dimensional stochastic seepage field problems.

  9. Asymmetric three-dimensional topography over mantle plumes.

    Science.gov (United States)

    Burov, Evgueni; Gerya, Taras

    2014-09-01

    The role of mantle-lithosphere interactions in shaping surface topography has long been debated. In general, it is supposed that mantle plumes and vertical mantle flows result in axisymmetric, long-wavelength topography, which strongly differs from the generally asymmetric short-wavelength topography created by intraplate tectonic forces. However, identification of mantle-induced topography is difficult, especially in the continents. It can be argued therefore that complex brittle-ductile rheology and stratification of the continental lithosphere result in short-wavelength modulation and localization of deformation induced by mantle flow. This deformation should also be affected by far-field stresses and, hence, interplay with the 'tectonic' topography (for example, in the 'active/passive' rifting scenario). Testing these ideas requires fully coupled three-dimensional numerical modelling of mantle-lithosphere interactions, which so far has not been possible owing to the conceptual and technical limitations of earlier approaches. Here we present new, ultra-high-resolution, three-dimensional numerical experiments on topography over mantle plumes, incorporating a weakly pre-stressed (ultra-slow spreading), rheologically realistic lithosphere. The results show complex surface evolution, which is very different from the smooth, radially symmetric patterns usually assumed as the canonical surface signature of mantle upwellings. In particular, the topography exhibits strongly asymmetric, small-scale, three-dimensional features, which include narrow and wide rifts, flexural flank uplifts and fault structures. This suggests a dominant role for continental rheological structure and intra-plate stresses in controlling dynamic topography, mantle-lithosphere interactions, and continental break-up processes above mantle plumes. PMID:25186903

  10. Three-dimensional numerical modeling of nearshore circulation

    Institute of Scientific and Technical Information of China (English)

    SUN Detong

    2008-01-01

    A three-dimensional nearshore circulation model was developed by coupling CH3D, a three-dimensional hydrodynamic model and REF/DIF, a nearsbore wave transformation model. The model solves the three-dimensional wave-averaged equations of motion. Wave-induced effects on circulation were introduced in the form of radiation stresses, wave-induced mass transport, wave-induced enhancement of bottom friction and wave-induced turbulent mixing. Effects of breaking waves were considered following Svendsen (1984a and 1984b) and Stive and Wind (1986). The model was successfully tested against the analytical solution of longshore currents by Longuet and Higgins (1970). The model successfully simulated the undertow as observed in a laboratory experiment by Stive and Wind (1982). In addition, the model was applied to a physical model by Mory and Hamm (1997) and successfully reproduced the eddy behind a detached breakwater as well as the longshore current on the open beach and the contiguous eddy in the open area of the wave tank. While the qualitative agreement between model results and experimental observations was very good, the quantitative agreement needs to be further improved. Albeit difficult to explain every discrepancy between the model re- suits and observations, in general, sources of errors are attributed to the lack of understanding and comprehensive description of following processes: (1) the horizontal and vertical distribution of radiation stress, especially for breaking waves; (2) the detailed structure of turbulence;(3)Wave-current interaction (not included at this moment) ; and (4)the wave- current boundary layer and the resulting bottom shear stress.

  11. Nonlinear three-dimensional beam theory for flexible multibody dynamics

    International Nuclear Information System (INIS)

    In flexible multibody systems, it is convenient to approximate many structural components as beams or shells. Classical beam theories, such as Euler–Bernoulli beam theory, often form the basis of the analytical development for beam dynamics. The advantage of this approach is that it leads to a very simple kinematic representation of the problem: the beam’s section is assumed to remain plane and its displacement field is fully defined by three displacement and three rotation components. While such an approach is capable of capturing the kinetic energy of the system accurately, it cannot represent the strain energy adequately. This paper presents a different approach to the problem. Based on a finite element discretization of the cross-section, an exact solution of the theory of three-dimensional elasticity is developed. The proposed approach is based on the Hamiltonian formalism and leads to an expansion of the solution in terms of extremity and central solutions. Kinematically, the problem is decomposed into an arbitrarily large rigid-section motion and a warping field. The sectional strains associated with the rigid-section motion and the warping field are assumed to remain small. As a consequence of this kinematic decomposition, the governing equations of the problem fall into two distinct categories: the equations describing geometrically exact beams and those describing local deformations. The governing equations for geometrically exact beams are nonlinear, one-dimensional equations, whereas a linear, two-dimensional analysis provides the detailed distribution of three-dimensional stress and strain fields. Within the stated assumptions, the solutions presented here are the exact solution of three-dimensional elasticity for beams undergoing arbitrarily large motions

  12. Nonlinear three-dimensional beam theory for flexible multibody dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Han, Shilei; Bauchau, Olivier A., E-mail: olivier.bauchau@sjtu.edu.cn [University of Michigan–Shanghai Jiao Tong University Joint Institute (China)

    2015-07-15

    In flexible multibody systems, it is convenient to approximate many structural components as beams or shells. Classical beam theories, such as Euler–Bernoulli beam theory, often form the basis of the analytical development for beam dynamics. The advantage of this approach is that it leads to a very simple kinematic representation of the problem: the beam’s section is assumed to remain plane and its displacement field is fully defined by three displacement and three rotation components. While such an approach is capable of capturing the kinetic energy of the system accurately, it cannot represent the strain energy adequately. This paper presents a different approach to the problem. Based on a finite element discretization of the cross-section, an exact solution of the theory of three-dimensional elasticity is developed. The proposed approach is based on the Hamiltonian formalism and leads to an expansion of the solution in terms of extremity and central solutions. Kinematically, the problem is decomposed into an arbitrarily large rigid-section motion and a warping field. The sectional strains associated with the rigid-section motion and the warping field are assumed to remain small. As a consequence of this kinematic decomposition, the governing equations of the problem fall into two distinct categories: the equations describing geometrically exact beams and those describing local deformations. The governing equations for geometrically exact beams are nonlinear, one-dimensional equations, whereas a linear, two-dimensional analysis provides the detailed distribution of three-dimensional stress and strain fields. Within the stated assumptions, the solutions presented here are the exact solution of three-dimensional elasticity for beams undergoing arbitrarily large motions.

  13. Three-Dimensional Numerical Simulation to Mud Turbine for LWD

    Science.gov (United States)

    Yao, Xiaojiang; Dong, Jingxin; Shang, Jie; Zhang, Guanqi

    Hydraulic performance analysis was discussed for a type of turbine on generator used for LWD. The simulation models were built by CFD analysis software FINE/Turbo, and full three-dimensional numerical simulation was carried out for impeller group. The hydraulic parameter such as power, speed and pressure drop, were calculated in two kinds of medium water and mud. Experiment was built in water environment. The error of numerical simulation was less than 6%, verified by experiment. Based on this rationalization proposals would be given to choice appropriate impellers, and the rationalization of methods would be explored.

  14. Three-dimensional imaging of direct-written photonic structures

    CERN Document Server

    Marshall, Graham D; Thayil, Anisha; Withford, Michael J; Booth, Martin

    2010-01-01

    Third harmonic generation microscopy has been used to analyze the morphology of photonic structures created using the femtosecond laser direct-write technique. Three dimensional waveguide arrays and waveguide-Bragg gratings written in fused-silica and doped phosphate glass were investigated. A sensorless adaptive optical system was used to correct the optical aberrations occurring in the sample and microscope system, which had a lateral resolution of less than 500 nm. This non-destructive testing method creates volume reconstructions of photonic devices and reveals details invisible to other linear microscopy and index profilometry techniques.

  15. The three-dimensional crystal structure of cholera toxin

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Rong-Guang; Westbrook, M.L.; Nance, S.; Spangler, B.D. [Argonne National Lab., IL (United States); Scott, D.L. [Yale Univ., New Haven, CT (United States). Dept. of Molecular Biophysics and Biochemistry; Westbrook, E.M. [Northwestern Univ., Evanston, IL (United States)

    1996-02-01

    The clinical manifestations of cholera are largely attributable to the actions of a secreted hexameric AB{sub 5} enterotoxin (choleragen). We have solved the three-dimensional structure of choleragen at 2.5 {Angstrom} resolution and compared the refined coordinates with those of choleragenoid (isolated B pentamer) and the heat-labile enterotoxin from Escherichia coli (LT). The crystalline coordinates provide a detailed view of the stereochemistry implicated in binding to GM1 gangliosides and in carrying out ADP-ribosylation. The A2 chain of choleragen, in contrast to that of LT, is a nearly continuous {alpha}-helix with an interpretable carboxyl tail.

  16. Three-dimensional global fluid simulations of cylindrical magnetized plasmas

    DEFF Research Database (Denmark)

    Naulin, Volker; Windisch, T.; Grulke, O.

    2008-01-01

    . Thus, it is possible to assess the reproductive and predictive capabilities of plasma simulations in unprecedented detail. Here, three-dimensional global fluid simulations of a cylindrical magnetized plasma are presented. This plasma is characterized by the existence of spatially localized sources and...... sinks. The traditional scale separation paradigm is not applied in the simulation model to account for the important evolution of the background profiles due to the dynamics of turbulent fluctuations. Furthermore, the fluid modeling of sheath boundary conditions, which determine the plasma conditions...

  17. Three dimensional simulations of the parallel velocity shear instability

    International Nuclear Information System (INIS)

    The authors have performed fully nonlinear three-dimensional fluid simulations of the electrostatic parallel velocity shear instability as applied to a tokamak edge plasma. In the present study a source terms in the parallel momentum equation drives the sheared parallel flow. Studied are the effects of magnetic shear on the turbulence of the mode and the associated fluctuation levels. The inclusion of the nonlinear polarization drift in the perpendicular dynamics is found to significantly affect the final nonlinear state. Dependence of the anomalous momentum transport on the magnetic shear and the gyroradius parameter, associated with the polarization drift, are presented

  18. Growing Three-Dimensional Cartilage-Cell Cultures

    Science.gov (United States)

    Spaulding, Glenn F.; Prewett, Tacey L.; Goodwin, Thomas J.

    1995-01-01

    Process for growing three-dimensional cultures of mammalian cartilage from normal mammalian cells devised. Effected using horizontal rotating bioreactor described in companion article, "Simplified Bioreactor for Growing Mammalian Cells" (MSC-22060). Bioreactor provides quiescent environment with generous supplies of nutrient and oxygen. Initiated with noncartilage cells. Artificially grown tissue resembles that in mammalian cartilage. Potential use in developing therapies for damage to cartilage by joint and back injuries and by such inflammatory diseases as arthritis and temporal-mandibular joint disease. Also used to test nonsteroid anti-inflammation medicines.

  19. Three-Dimensional Model for Strip Hot Rolling

    Institute of Scientific and Technical Information of China (English)

    ZHANG Guo-min; XIAO Hong; WANG Chun-hua

    2006-01-01

    A three-dimensional model for strip hot rolling was developed, in which the plastic deformation of strip, the thermal crown of rolls, roll deflection and flattening were calculated by rigid-plastic finite element method, finite difference method, influential function method and elastic finite element method respectively. The roll wear was taken into consideration. The model can provide detailed information such as rolling pressure distribution, contact pressure distribution between backup rolls and work rolls, deflection and flattening of work rolls, lateral distribution of strip thickness, and lateral distribution of front and back tensions. The finish rolling on a 1 450 mm hot strip mill was simulated.

  20. Geometry and observables in three-dimensional (quantum) gravity

    International Nuclear Information System (INIS)

    Three-dimensional gravity serves as a model in which fundamental questions of quantum gravity can be investigated in a fully and rigorously quantised theory. A central question for its interpretation is the relation between the fundamental diffeomorphism invariant observables of the theory and the geometry of the spacetimes. We show how these observables can be related to concrete measurements by observers in terms of light-rays. These measurements allow the observer to fully determine the geometry of the spacetime in finite eigentime.

  1. Three-dimensional characterization of stress corrosion cracks

    DEFF Research Database (Denmark)

    Lozano-Perez, S.; Rodrigo, P.; Gontard, Lionel Cervera

    2011-01-01

    offers the best spatial resolution. To illustrate the power of these techniques, different parts of dominant stress corrosion cracks in Ni-alloys and stainless steels have been reconstructed in 3D. All relevant microstructural features can now be studied in detail and its relative orientation respect to......Understanding crack propagation and initiation is fundamental if stress corrosion cracking (SCC) mechanisms are to be understood. However, cracking is a three-dimensional (3D) phenomenon and most characterization techniques are restricted to two-dimensional (2D) observations. In order to overcome...

  2. Analytic WKB energy expressions for three-dimensional anharmonic oscillators

    International Nuclear Information System (INIS)

    A direct evaluation of the lowest-order WKB integral for three-dimensional quartic (V(r)=r4) and quartic anharmonic (V(r)=1/2ω2r2 + lambdar4) oscillators is carried out. The highly implicit relation for the energy defined by the WKB quantisation condition is expressed in terms of complete elliptic integrals. An approximate non-perturbative inversion of the implicit relation provides explicit analytic expressions for the energy which reproduce known energy values quite accurately. (author)

  3. Three-dimensional Josephson-junction arrays: Static magnetic response

    International Nuclear Information System (INIS)

    In this work we present a simple three-dimensional Josephson-junction array model: a cube with twelve junctions, one on each edge. The low-field magnetic response of the system is studied numerically for arbitrary directions of the applied field. In this model the magnetic energy of the circulating currents is taken into account by introducing an effective mutual inductance matrix. The lower threshold field for flux penetration is determined in a closed analytic form for field directions perpendicular to one cube side. copyright 1998 The American Physical Society

  4. Black holes in three-dimensional dilaton gravity theories

    CERN Document Server

    Sá, P M; Lemos, J P S; Sa, Paulo M; Kleber, Antares; Lemos, Jose P S

    1995-01-01

    Three dimensional black holes in a generalized dilaton gravity action theory are analysed. The theory is specified by two fields, the dilaton and the graviton, and two parameters, the cosmological constant and the Brans-Dicke parameter. It contains seven different cases, of which one distinguishes as special cases, string theory, general relativity and a theory equivalent to four dimensional general relativity with one Killing vector. We study the causal structure and geodesic motion of null and timelike particles in the black hole geometries and find the ADM masses of the different solutions.

  5. Combinatorial topology of three-dimensional self-affine tiles

    CERN Document Server

    Bandt, Christoph

    2010-01-01

    We develop tools to study the topology and geometry of self-affine fractals in dimension three and higher. We use the self-affine structure and obtain rather detailed information about the connectedness of interior and boundary sets, and on the dimensions and intersections of boundary sets. As an application, we describe in algebraic terms the polyhedral structure of the six fractal three-dimensional twindragons. Only two of them can be homeomorphic to a ball but even these have faces which are not homeomorphic to a disk.

  6. Photonic Paint Developed with Metallic Three-Dimensional Photonic Crystals

    Directory of Open Access Journals (Sweden)

    John D. Williams

    2012-07-01

    Full Text Available This work details the design and simulation of an inconspicuous photonic paint that can be applied onto an object for anticounterfeit and tag, track, and locate (TTL applications. The paint consists of three-dimensional metallic tilted woodpile photonic crystals embedded into a visible and infrared transparent polymer film, which can be applied to almost any surface. The tilted woodpile photonic crystals are designed with a specific pass band detectable at nearly all incident angles of light. When painted onto a surface, these crystals provide a unique reflective infra-red optical signature that can be easily observed and recorded to verify the location or contents of a package.

  7. Terrain classification in complex three-dimensional outdoor environments

    OpenAIRE

    Santamaria Navarro, Àngel; Teniente Avilés, Ernesto Homar; Morta Garriga, Martí; Andrade-Cetto, Juan

    2015-01-01

    This paper presents two techniques to detect and classify navigable terrain in complex three-dimensional (3D) environments. The first method is a low level on-line mechanism aimed at detecting obstacles and holes at a fast frame rate using a time-of-flight camera as the main sensor. The second technique is a high-level offline classification mechanism that learns traversable regions from larger 3D point clouds acquired with a laser range scanner. We approach the problem using Gaussian process...

  8. Three dimensional separation trap based on dielectrophoresis and use thereof

    Science.gov (United States)

    Mariella, Jr., Raymond P.

    2004-05-04

    An apparatus is adapted to separate target materials from other materials in a flow containing the target materials and other materials. A dielectrophoretic trap is adapted to receive the target materials and the other materials. At least one electrode system is provided in the trap. The electrode system has a three-dimensional configuration. The electrode system includes a first electrode and a second electrode that are shaped and positioned relative to each such that application of an electrical voltage to the first electrode and the second electrode creates a dielectrophoretic force and said dielectrophoretic force does not reach zero between the first electrode and the second electrode.

  9. Three-dimensional illumination procedure for photodynamic therapy of dermatology

    Science.gov (United States)

    Hu, Xiao-ming; Zhang, Feng-juan; Dong, Fei; Zhou, Ya

    2014-09-01

    Light dosimetry is an important parameter that affects the efficacy of photodynamic therapy (PDT). However, the irregular morphologies of lesions complicate lesion segmentation and light irradiance adjustment. Therefore, this study developed an illumination demo system comprising a camera, a digital projector, and a computing unit to solve these problems. A three-dimensional model of a lesion was reconstructed using the developed system. Hierarchical segmentation was achieved with the superpixel algorithm. The expected light dosimetry on the targeted lesion was achieved with the proposed illumination procedure. Accurate control and optimization of light delivery can improve the efficacy of PDT.

  10. A Novel Woodpile Three-Dimensional Terahertz Photonic Crystal

    Institute of Scientific and Technical Information of China (English)

    LIU Huan; YAO Jian-Quan; ZHENG Fang-Hua; XU De-Gang; WANG Peng

    2007-01-01

    A novel woodpile lattice structure is proposed. Based on plane wave expansion (PWE) method, the complete photonic band gaps (PBGs) of the novel woodpile three-dimensional (3D) terahertz (THz) photonic crystal (PC) with a decreasing symmetry relative to a face-centred-tetragonal (fct) symmetry are optimized by varying some structural parameters and the highest band gap ratio can reach 27.61%. Compared to the traditional woodpile lattice, the novel woodpile lattice has a wider range of the Riling ratios to gain high quality PBGs, which provides greater convenience for the manufacturing process. The novel woodpile 3D PC will be very promising for materials of THz functional components.

  11. Three dimensional vision - Requirements and applications in a space environment

    Science.gov (United States)

    Noseworthy, J. R.; Gerhardt, Lester A.

    1991-01-01

    Various approaches to three-dimensional vision in space are reviewed with emphasis on the redundant 3D vision system designed for the Center for Intelligent Robotic Systems for Space Exploration. The system uses a controllable subset of five cameras, programmable structured light patterns, and sophisticated calibration routines. The design emphasizes real-time operation, human supervisory intervention, and the use of 3D vision to enhance the performance of cooperating robotic arms. Two methods of estimating the location of a point using 3D vision are discussed.

  12. Planar and Three-Dimensional Printing of Conductive Inks

    OpenAIRE

    Ahn, Bok Yeop; Walker, Steven B.; Slimmer, Scott C.; Russo, Analisa; Gupta, Ashley; Kranz, Steve; Duoss, Eric B.; Malkowski, Thomas F.; Lewis, Jennifer A.

    2011-01-01

    Printed electronics rely on low-cost, large-area fabrication routes to create flexible or multidimensional electronic, optoelectronic, and biomedical devices1-3. In this paper, we focus on one- (1D), two- (2D), and three-dimensional (3D) printing of conductive metallic inks in the form of flexible, stretchable, and spanning microelectrodes. Direct-write assembly4,5 is a 1-to-3D printing technique that enables the fabrication of features ranging from simple lines to complex structures by the d...

  13. Wave field restoration using three-dimensional Fourier filtering method.

    Science.gov (United States)

    Kawasaki, T; Takai, Y; Ikuta, T; Shimizu, R

    2001-11-01

    A wave field restoration method in transmission electron microscopy (TEM) was mathematically derived based on a three-dimensional (3D) image formation theory. Wave field restoration using this method together with spherical aberration correction was experimentally confirmed in through-focus images of amorphous tungsten thin film, and the resolution of the reconstructed phase image was successfully improved from the Scherzer resolution limit to the information limit. In an application of this method to a crystalline sample, the surface structure of Au(110) was observed in a profile-imaging mode. The processed phase image showed quantitatively the atomic relaxation of the topmost layer. PMID:11794629

  14. Three Dimensional Digital Image Processing using Edge Detectors

    Directory of Open Access Journals (Sweden)

    John Schmeelk

    2005-11-01

    Full Text Available This paper provides an introduction to three dimensional image edge detection and its relationship to partial derivatives, convolutions and wavelets. We are especially addressing the notion of edge detection because it has far reaching applications in all areas of research to include medical research. A patient can be diagnosed as having an aneurysm by studying an angiogram. An angiogram is the visual view of the blood vessels whereby the edges are highlighted through the implementation of edge detectors. This process is completed through convolution, wavelets and matrix techniques. Some illustrations included will be vertical, horizontal, Sobel and wavelet edge detectors.

  15. Distributional properties of the three-dimensional Poisson Delaunay cell

    International Nuclear Information System (INIS)

    This paper gives distributional properties of geometrical characteristics of the Delaunay tessellation generated by a stationary Poisson point process in Re 3. The considerations are based on a well-known formula given by Miles which describes the size and shape of the open-quotes typicalclose quotes three-dimensional Poisson Delaunay cell. The results are the probability density functions for its volume, the area, and the perimeter of one of its faces, the angle spanned in a face by two of its edges, and the length of an edge. These probability density functions are given in integral form. Formulas for higher moments of these characteristics are given explicitly

  16. Distributional properties of the three-dimensional Poisson Delaunay cell

    Science.gov (United States)

    Muche, Lutz

    1996-07-01

    This paper gives distributional properties of geometrical characteristics of the Delaunay tessellation generated by a stationary Poisson point process in ℝ3. The considerations are based on a well-known formula given by Miles which describes the size and shape of the "typical" three-dimensional Poisson Delaunay cell. The results are the probability density functions for its volume, the area, and the perimeter of one of its faces, the angle spanned in a face by two of its edges, and the length of an edge. These probability density functions are given in integral form. Formulas for higher moments of these characteristics are given explicitly.

  17. Three-Dimensional Patterning Using Ultraviolet Nanoimprint Lithography

    OpenAIRE

    Alkaisi, Maan M; Mohamed, Khairudin

    2010-01-01

    Direct three-dimensional patterning is demonstrated using UV cured nanoimprint lithography (UVNIL). The 3-D mold profiles were created on the ma-N2403 negative tone photoresist using the Raith-150 EBL tool with variable dose controlled exposure. A variable e-beam dose was used to obtain a resist contrast curve to determine the gradient of various 3-D structures. For a 600 nm layer thickness of ma-N2403 resist, the e-beam critical energy was set at 6.25 keV. To suppress charging effects on ins...

  18. Three-dimensional numerical modelling of sediments in water reservoirs

    OpenAIRE

    Hoven, Lisa Emilie

    2010-01-01

    Many places in the world the rivers transport a lot of sediments. When these sediments enter slow flowing areas like a water reservoir, the sediments are deposited. This leads to a reduction in the volume of the reservoir. The object of this project is to do three-dimensional numerical modelling of sediments in a water reservoir in using the SSIIM model. The chosen reservoir is the Angostura reservoir in Costa Rica. This reservoir has significant sediment problems and is flushed two times per...

  19. Magneto-resistance in three-dimensional composites.

    OpenAIRE

    Briane, Marc; Pater, Laurent

    2014-01-01

    In this paper we study the magneto-resistance, i.e. the second-order term of the resistivity perturbed by a low magnetic field, of a three-dimensional composite material. Extending the two-dimensional periodic framework of [M. Briane, Homogenization of the magneto-resistance in dimension two, M3AS, 20 (7) (2010), 1161-1177], it is proved through a H-convergence approach that the dissipation energy induced by the effective magneto-resistance is greater or equal to the average of the dissipatio...

  20. On three-dimensional trace anomaly from holographic local RG

    CERN Document Server

    Kikuchi, Ken; Suzuki, Akihiro

    2016-01-01

    Odd-dimensional quantum field theories (QFTs) can have nonzero trace anomalies if external fields are introduced and some ingredients needed to make Lorentz scalars with appropriate mass dimensions (or weights) are supplied. We have studied a three-dimensional QFT and explicitly computed the trace of the stress tensor using the holographic local renormalization group (RG). We have checked some properties of vector beta functions and the Wess-Zumino consistency condition, however, found the anomalies vanish on fixed points. We clarify what is responsible for the vanishing trace anomalies.