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Sample records for scaffoldless three-dimensional engineered

  1. Scaffoldless tissue-engineered dental pulp cell constructs for endodontic therapy.

    Science.gov (United States)

    Syed-Picard, F N; Ray, H L; Kumta, P N; Sfeir, C

    2014-03-01

    A major cause of apical periodontitis after endodontic treatment is the bacterial infiltration which could have been challenged by the presence of a vital pulp. In this study, self-assembled, scaffoldless, three-dimensional (3D) tissues were engineered from dental pulp cells (DPCs) and assessed as a device for pulp regeneration. These engineered tissues were placed into the canal space of human tooth root segments that were capped on one end with calcium phosphate cement, and the entire system was implanted subcutaneously into mice. Histological staining indicated that after three- and five-month implantations, tooth roots containing 3D scaffoldless engineered tissues maintained a cellular, fibrous tissue throughout, whereas empty tooth roots remained predominantly empty. Immunostaining indicated that the tissue found in the root canals containing scaffoldless DPC engineered tissues was vascular, as characterized by the expression of CD31, and contained odontoblast-like cells organized along the length of the root wall as assessed by immunostaining for dentin sialoprotein. This study shows that 3D self-assembled scaffoldless DPC engineered tissues can regenerate a vital dental pulp-like tissue in a tooth root canal system and are therefore promising for endodontic therapy.

  2. Scaffoldless engineered enzyme assembly for enhanced methanol utilization.

    Science.gov (United States)

    Price, J Vincent; Chen, Long; Whitaker, W Brian; Papoutsakis, Eleftherios; Chen, Wilfred

    2016-10-24

    Methanol is an important feedstock derived from natural gas and can be chemically converted into commodity and specialty chemicals at high pressure and temperature. Although biological conversion of methanol can proceed at ambient conditions, there is a dearth of engineered microorganisms that use methanol to produce metabolites. In nature, methanol dehydrogenase (Mdh), which converts methanol to formaldehyde, highly favors the reverse reaction. Thus, efficient coupling with the irreversible sequestration of formaldehyde by 3-hexulose-6-phosphate synthase (Hps) and 6-phospho-3-hexuloseisomerase (Phi) serves as the key driving force to pull the pathway equilibrium toward central metabolism. An emerging strategy to promote efficient substrate channeling is to spatially organize pathway enzymes in an engineered assembly to provide kinetic driving forces that promote carbon flux in a desirable direction. Here, we report a scaffoldless, self-assembly strategy to organize Mdh, Hps, and Phi into an engineered supramolecular enzyme complex using an SH3-ligand interaction pair, which enhances methanol conversion to fructose-6-phosphate (F6P). To increase methanol consumption, an "NADH Sink" was created using Escherichia coli lactate dehydrogenase as an NADH scavenger, thereby preventing reversible formaldehyde reduction. Combination of the two strategies improved in vitro F6P production by 97-fold compared with unassembled enzymes. The beneficial effect of supramolecular enzyme assembly was also realized in vivo as the engineered enzyme assembly improved whole-cell methanol consumption rate by ninefold. This approach will ultimately allow direct coupling of enhanced F6P synthesis with other metabolic engineering strategies for the production of many desired metabolites from methanol.

  3. Heat engine in the three-dimensional spacetime

    International Nuclear Information System (INIS)

    Mo, Jie-Xiong; Liang, Feng; Li, Gu-Qiang

    2017-01-01

    We define a kind of heat engine via three-dimensional charged BTZ black holes. This case is quite subtle and needs to be more careful. The heat flow along the isochores does not equal to zero since the specific heat C V ≠0 and this point completely differs from the cases discussed before whose isochores and adiabats are identical. So one cannot simply apply the paradigm in the former literatures. However, if one introduces a new thermodynamic parameter associated with the renormalization length scale, the above problem can be solved. We obtain the analytical efficiency expression of the three-dimensional charged BTZ black hole heat engine for two different schemes. Moreover, we double check with the exact formula. Our result presents the first specific example for the sound correctness of the exact efficiency formula. We argue that the three-dimensional charged BTZ black hole can be viewed as a toy model for further investigation of holographic heat engine. Furthermore, we compare our result with that of the Carnot cycle and extend the former result to three-dimensional spacetime. In this sense, the result in this paper would be complementary to those obtained in four-dimensional spacetime or ever higher. Last but not the least, the heat engine efficiency discussed in this paper may serve as a criterion to discriminate the two thermodynamic approaches introduced in ref. https://www.doi.org/10.1103/PhysRevD.92.124069 and our result seems to support the approach which introduces a new thermodynamic parameter R=r 0 .

  4. Heat engine in the three-dimensional spacetime

    Energy Technology Data Exchange (ETDEWEB)

    Mo, Jie-Xiong [Institute of Theoretical Physics, Lingnan Normal University,Zhanjiang, 524048, Guangdong (China); Department of Physics, Lingnan Normal University,Zhanjiang, 524048, Guangdong (China); Liang, Feng [Department of Physics, Lingnan Normal University,Zhanjiang, 524048, Guangdong (China); Li, Gu-Qiang [Institute of Theoretical Physics, Lingnan Normal University,Zhanjiang, 524048, Guangdong (China); Department of Physics, Lingnan Normal University,Zhanjiang, 524048, Guangdong (China)

    2017-03-02

    We define a kind of heat engine via three-dimensional charged BTZ black holes. This case is quite subtle and needs to be more careful. The heat flow along the isochores does not equal to zero since the specific heat C{sub V}≠0 and this point completely differs from the cases discussed before whose isochores and adiabats are identical. So one cannot simply apply the paradigm in the former literatures. However, if one introduces a new thermodynamic parameter associated with the renormalization length scale, the above problem can be solved. We obtain the analytical efficiency expression of the three-dimensional charged BTZ black hole heat engine for two different schemes. Moreover, we double check with the exact formula. Our result presents the first specific example for the sound correctness of the exact efficiency formula. We argue that the three-dimensional charged BTZ black hole can be viewed as a toy model for further investigation of holographic heat engine. Furthermore, we compare our result with that of the Carnot cycle and extend the former result to three-dimensional spacetime. In this sense, the result in this paper would be complementary to those obtained in four-dimensional spacetime or ever higher. Last but not the least, the heat engine efficiency discussed in this paper may serve as a criterion to discriminate the two thermodynamic approaches introduced in ref. https://www.doi.org/10.1103/PhysRevD.92.124069 and our result seems to support the approach which introduces a new thermodynamic parameter R=r{sub 0}.

  5. Engineering three-dimensional cell mechanical microenvironment with hydrogels.

    Science.gov (United States)

    Huang, Guoyou; Wang, Lin; Wang, Shuqi; Han, Yulong; Wu, Jinhui; Zhang, Qiancheng; Xu, Feng; Lu, Tian Jian

    2012-12-01

    Cell mechanical microenvironment (CMM) significantly affects cell behaviors such as spreading, migration, proliferation and differentiation. However, most studies on cell response to mechanical stimulation are based on two-dimensional (2D) planar substrates, which cannot mimic native three-dimensional (3D) CMM. Accumulating evidence has shown that there is a significant difference in cell behavior in 2D and 3D microenvironments. Among the materials used for engineering 3D CMM, hydrogels have gained increasing attention due to their tunable properties (e.g. chemical and mechanical properties). In this paper, we provide an overview of recent advances in engineering hydrogel-based 3D CMM. Effects of mechanical cues (e.g. hydrogel stiffness and externally induced stress/strain in hydrogels) on cell behaviors are described. A variety of approaches to load mechanical stimuli in 3D hydrogel-based constructs are also discussed.

  6. Utilizing stem cells for three-dimensional neural tissue engineering.

    Science.gov (United States)

    Knowlton, Stephanie; Cho, Yongku; Li, Xue-Jun; Khademhosseini, Ali; Tasoglu, Savas

    2016-05-26

    Three-dimensional neural tissue engineering has made great strides in developing neural disease models and replacement tissues for patients. However, the need for biomimetic tissue models and effective patient therapies remains unmet. The recent push to expand 2D neural tissue engineering into the third dimension shows great potential to advance the field. Another area which has much to offer to neural tissue engineering is stem cell research. Stem cells are well known for their self-renewal and differentiation potential and have been shown to give rise to tissues with structural and functional properties mimicking natural organs. Application of these capabilities to 3D neural tissue engineering may be highly useful for basic research on neural tissue structure and function, engineering disease models, designing tissues for drug development, and generating replacement tissues with a patient's genetic makeup. Here, we discuss the vast potential, as well as the current challenges, unique to integration of 3D fabrication strategies and stem cells into neural tissue engineering. We also present some of the most significant recent achievements, including nerve guidance conduits to facilitate better healing of nerve injuries, functional 3D biomimetic neural tissue models, physiologically relevant disease models for research purposes, and rapid and effective screening of potential drugs.

  7. Engineering Three-dimensional Epithelial Tissues Embedded within Extracellular Matrix.

    Science.gov (United States)

    Piotrowski-Daspit, Alexandra S; Nelson, Celeste M

    2016-07-10

    The architecture of branched organs such as the lungs, kidneys, and mammary glands arises through the developmental process of branching morphogenesis, which is regulated by a variety of soluble and physical signals in the microenvironment. Described here is a method created to study the process of branching morphogenesis by forming engineered three-dimensional (3D) epithelial tissues of defined shape and size that are completely embedded within an extracellular matrix (ECM). This method enables the formation of arrays of identical tissues and enables the control of a variety of environmental factors, including tissue geometry, spacing, and ECM composition. This method can also be combined with widely used techniques such as traction force microscopy (TFM) to gain more information about the interactions between cells and their surrounding ECM. The protocol can be used to investigate a variety of cell and tissue processes beyond branching morphogenesis, including cancer invasion.

  8. Hydrogel microfabrication technology toward three dimensional tissue engineering

    Directory of Open Access Journals (Sweden)

    Fumiki Yanagawa

    2016-03-01

    Full Text Available The development of biologically relevant three-dimensional (3D tissue constructs is essential for the alternative methods of organ transplantation in regenerative medicine, as well as the development of improved drug discovery assays. Recent technological advances in hydrogel microfabrication, such as micromolding, 3D bioprinting, photolithography, and stereolithography, have led to the production of 3D tissue constructs that exhibit biological functions with precise 3D microstructures. Furthermore, microfluidics technology has enabled the development of the perfusion culture of 3D tissue constructs with vascular networks. In this review, we present these hydrogel microfabrication technologies for the in vitro reconstruction and cultivation of 3D tissues. Additionally, we discuss current challenges and future perspectives of 3D tissue engineering.

  9. Three-Dimensional Analysis and Modeling of a Wankel Engine

    Science.gov (United States)

    Raju, M. S.; Willis, E. A.

    1991-01-01

    A new computer code, AGNI-3D, has been developed for the modeling of combustion, spray, and flow properties in a stratified-charge rotary engine (SCRE). The mathematical and numerical details of the new code are described by the first author in a separate NASA publication. The solution procedure is based on an Eulerian-Lagrangian approach where the unsteady, three-dimensional Navier-Stokes equations for a perfect gas-mixture with variable properties are solved in generalized, Eulerian coordinates on a moving grid by making use of an implicit finite-volume, Steger-Warming flux vector splitting scheme. The liquid-phase equations are solved in Lagrangian coordinates. The engine configuration studied was similar to existing rotary engine flow-visualization and hot-firing test rigs. The results of limited test cases indicate a good degree of qualitative agreement between the predicted and measured pressures. It is conjectured that the impulsive nature of the torque generated by the observed pressure nonuniformity may be one of the mechanisms responsible for the excessive wear of the timing gears observed during the early stages of the rotary combustion engine (RCE) development. It was identified that the turbulence intensities near top-dead-center were dominated by the compression process and only slightly influenced by the intake and exhaust processes. Slow mixing resulting from small turbulence intensities within the rotor pocket and also from a lack of formation of any significant recirculation regions within the rotor pocket were identified as the major factors leading to incomplete combustion. Detailed flowfield results during exhaust and intake, fuel injection, fuel vaporization, combustion, mixing and expansion processes are also presented. The numerical procedure is very efficient as it takes 7 to 10 CPU hours on a CRAY Y-MP for one entire engine cycle when the computations are performed over a 31 x16 x 20 grid.

  10. Engineered three-dimensional multicellular culture model to ...

    Science.gov (United States)

    Tissue fusion during early mammalian development requires crosstalk between multiple cell types. For example, paracrine signaling between palatal epithelial cells and palatal mesenchyme mediates the fusion of opposing palatal shelves during embryonic development. Fusion events in developmental processes including heart development, neural tube closure, and palatal fusion are dependent on epithelial-mesenchymal interactions (EMIs) and specific signaling pathways that have been elucidated largely using gene knockout mouse models. A broad analysis of literature using ToxRefDB identified 63 ToxCast chemicals associated with cleft palate in animal models. However, the influence of these and other putative teratogens on human palatal fusion has not been examined in depth due to the lack of in vitro models incorporating EMIs between human cell types. We sought to engineer the stratified mesenchymal and epithelial structure of the developing palate in vitro using spheroid culture of human Wharton’s Jelly mesenchymal stem cells (hMSC). hMSC spheroids exhibited uniform size over time (175 ± 21 µm mean diameter) that was proportional to starting cell density. Further, hMSCs in spheroid culture exhibited increased alkaline phosphatase activity and increased expression of bglap and runx2 after 7 days of culture in osteo-induction medium, which suggests that spheroid culture together with osteo-induction medium supports osteogenic differentiation. We developed a novel pro

  11. Potential Health and Environmental Risks of Three-Dimensional Engineered Polymers

    NARCIS (Netherlands)

    De Almeida Monteiro Melo Ferraz, Marcia; Henning, Heiko H.W.; Da Costa, Pedro Ferreira; Malda, Jos; Le Gac, Séverine; Bray, Fabrice; Van Duursen, Majorie B.M.; Brouwers, Jos F.; Van De Lest, Chris H.A.; Bertijn, Ingeborg; Kraneburg, Lisa; Vos, Peter L.A.M.; Stout, Tom A.E.; Gadella, Barend M.

    2018-01-01

    Polymer engineering, such as in three-dimensional (3D) printing, is rapidly gaining popularity, not only in the scientific and medical fields but also in the community in general. However, little is known about the toxicity of engineered materials. Therefore, we assessed the toxicity of 3D-printed

  12. Engineering topological phases with a three-dimensional nodal-loop semimetal

    Science.gov (United States)

    Li, Linhu; Yap, Han Hoe; Araújo, Miguel A. N.; Gong, Jiangbin

    2017-12-01

    A three-dimensional (3D) nodal-loop semimetal phase is exploited to engineer a number of intriguing phases featuring different peculiar topological surface states. In particular, by introducing various two-dimensional gap terms to a 3D tight-binding model of a nodal-loop semimetal, we obtain a rich variety of topological phases of great interest to ongoing theoretical and experimental studies, including a chiral insulator, degenerate-surface-loop insulator, and second-order topological insulator, as well as a Weyl semimetal with tunable Fermi arc profiles. The unique concept underlying our approach is to engineer topological surface states that inherit their dispersion relations from a gap term. The results provide one rather unified principle for the creation of novel topological phases and can guide the search for new topological materials. Two-terminal transport studies are also carried out to distinguish the engineered topological phases.

  13. Application of an engineering inviscid-boundary layer method to slender three-dimensional vehicle forebodies

    Science.gov (United States)

    Riley, Christopher J.

    1993-01-01

    An engineering inviscid-boundary layer method has been modified for application to slender three-dimensional (3-D) forebodies which are characteristic of transatmospheric vehicles. An improved shock description in the nose region has been added to the inviscid technique which allows the calculation of a wider range of body geometries. The modified engineering method is applied to the perfect gas solution over a slender 3-D configuration at angle of attack. The method predicts surface pressures and laminar heating rates on the windward side of the vehicle that compare favorably with numerical solutions of the thin-layer Navier-Stokes equations. These improvements extend the 3-D capabilities of the engineering method and significantly increase its design applications.

  14. Three-Dimensional Numerical Analysis of LOX/Kerosene Engine Exhaust Plume Flow Field Characteristics

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    Hong-hua Cai

    2017-01-01

    Full Text Available Aiming at calculating and studying the flow field characteristics of engine exhaust plume and comparative analyzing the effects of different chemical reaction mechanisms on the engine exhaust plume flow field characteristics, a method considering fully the combustion state influence is put forward, which is applied to exhaust plume flow field calculation of multinozzle engine. On this basis, a three-dimensional numerical analysis of the effects of different chemical reaction mechanisms on LOX/kerosene engine exhaust plume flow field characteristics was carried out. It is found that multistep chemical reaction can accurately describe the combustion process in the LOX/kerosene engine, the average chamber pressure from the calculation is 4.63% greater than that of the test, and the average chamber temperature from the calculation is 3.34% greater than that from the thermodynamic calculation. The exhaust plumes of single nozzle and double nozzle calculated using the global chemical reaction are longer than those using the multistep chemical reaction; the highest temperature and the highest velocity on the plume axis calculated using the former are greater than that using the latter. The important influence of chemical reaction mechanism must be considered in the study of the fixing structure of double nozzle engine on the rocket body.

  15. Three-dimensional modeling of diesel engine intake flow, combustion and emissions-II

    Energy Technology Data Exchange (ETDEWEB)

    Reitz, R.D.; Rutland, C.J.

    1993-09-01

    A three-dimensional computer code, KIVA, is being modified to include state-of-the-art submodels for diesel engine flow and combustion. Improved and/or new submodels which have already been implemented and previously reported are: Wall heat transfer with unsteadiness and compressibility, laminar-turbulent characteristic time combustion with unburned HC and Zeldo`vich NO{sub x}, and spray/wall impingement with rebounding and sliding drops. Progress on the implementation of improved spray drop drag and drop breakup models, the formulation and testing of a multistep kinetics ignition model and preliminary soot modeling results are described in this report. In addition, the use of a block structured version of KIVA to model the intake flow process is described. A grid generation scheme has been developed for modeling realistic (complex) engine geometries, and computations have been made of intake flow in the ports and combustion chamber of a two-intake-valve engine. The research also involves the use of the code to assess the effects of subprocesses on diesel engine performance. The accuracy of the predictions is being tested by comparisons with engine experiments. To date, comparisons have been made with measured engine cylinder pressure, temperature and heat flux data, and the model results are in good agreement with the experiments. Work is in progress that will allow validation of in-cylinder flow and soot formation predictions. An engine test facility is described that is being used to provide the needed validation data. Test results have been obtained showing the effect of injection rate and split injections on engine performance and emissions.

  16. A Review of the Responses of Two- and Three-Dimensional Engineered Tissues to Electric Fields

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    Hronik-Tupaj, Marie

    2012-01-01

    The application of external biophysical signals is one approach to tissue engineering that is explored less often than more traditional additions of exogenous biochemical and chemical factors to direct cell and tissue outcomes. The study of bioelectromagnetism and the field of electrotherapeutics have evolved over the years, and we review biocompatible electric stimulation devices and their successful application to tissue growth. Specifically, information on capacitively coupled alternating current, inductively coupled alternating current, and direct current devices is described. Cell and tissue responses from the application of these devices, including two- and three-dimensional in vitro studies and in vivo studies, are reviewed with regard to cell proliferation, adhesion, differentiation, morphology, and migration and tissue function. The current understanding of cellular mechanisms related to electric stimulation is detailed. The advantages of electric stimulation are compared with those pf other techniques, and areas in which electric fields are used as an adjuvant therapy for healing and regeneration are discussed. PMID:22046979

  17. Online monitoring of mechanical properties of three-dimensional tissue engineered constructs for quality assessment

    Science.gov (United States)

    Reinwald, Yvonne; Bagnaninchi, Pierre O.; Yang, Ying; Baba Ismail, Yanny M.; El Haj, Alicia J.

    2016-03-01

    Mechanical preconditioning and mechanical properties of tissue engineered constructs are essential for their capability to regenerate damaged tissues. To online monitor the mechanical properties a hydrostatic pressure bioreactor was coupled with optical coherence tomography into a new image modality termed hydrostatic pressure optical coherence elastography (HP-OCE). HP-OCE was utilised to assess the properties of three-dimensional (3D) tissue constructs while being physically stimulated within the hydrostatic force bioreactor. Hydrogels have been infiltrated into porous rapid prototyped or salt-leached scaffolds to mimic heterogeneous mechanical properties of cell-seeded constructs. Variations of mechanical properties in the solid scaffolds and agarose gels with different gel concentrations as well as the presences of cells have been clearly delineated by HP-OCE. Results indicate that HP-OCE allows contactless real-time non-invasive monitoring of the mechanical properties of tissue constructs and the effect of physical stimulation on cellular activities.

  18. Mechanical stretching for tissue engineering: two-dimensional and three-dimensional constructs.

    Science.gov (United States)

    Riehl, Brandon D; Park, Jae-Hong; Kwon, Il Keun; Lim, Jung Yul

    2012-08-01

    Mechanical cell stretching may be an attractive strategy for the tissue engineering of mechanically functional tissues. It has been demonstrated that cell growth and differentiation can be guided by cell stretch with minimal help from soluble factors and engineered tissues that are mechanically stretched in bioreactors may have superior organization, functionality, and strength compared with unstretched counterparts. This review explores recent studies on cell stretching in both two-dimensional (2D) and three-dimensional (3D) setups focusing on the applications of stretch stimulation as a tool for controlling cell orientation, growth, gene expression, lineage commitment, and differentiation and for achieving successful tissue engineering of mechanically functional tissues, including cardiac, muscle, vasculature, ligament, tendon, bone, and so on. Custom stretching devices and lab-specific mechanical bioreactors are described with a discussion on capabilities and limitations. While stretch mechanotransduction pathways have been examined using 2D stretch, studying such pathways in physiologically relevant 3D environments may be required to understand how cells direct tissue development under stretch. Cell stretch study using 3D milieus may also help to develop tissue-specific stretch regimens optimized with biochemical feedback, which once developed will provide optimal tissue engineering protocols.

  19. Metabolically Active Three-Dimensional Brown Adipose Tissue Engineered from White Adipose-Derived Stem Cells.

    Science.gov (United States)

    Yang, Jessica P; Anderson, Amy E; McCartney, Annemarie; Ory, Xavier; Ma, Garret; Pappalardo, Elisa; Bader, Joel; Elisseeff, Jennifer H

    2017-04-01

    Brown adipose tissue (BAT) has a unique capacity to expend calories by decoupling energy expenditure from ATP production, therefore BAT could realize therapeutic potential to treat metabolic diseases such as obesity and type 2 diabetes. Recent studies have investigated markers and function of native BAT, however, successful therapies will rely on methods that supplement the small existing pool of brown adipocytes in adult humans. In this study, we engineered BAT from both human and rat adipose precursors and determined whether these ex vivo constructs could mimic in vivo tissue form and metabolic function. Adipose-derived stem cells (ASCs) were isolated from several sources, human white adipose tissue (WAT), rat WAT, and rat BAT, then differentiated toward both white and brown adipogenic lineages in two-dimensional and three-dimensional (3D) culture conditions. ASCs derived from WAT were successfully differentiated in 3D poly(ethylene glycol) hydrogels into mature adipocytes with BAT phenotype and function, including high uncoupling protein 1 (UCP1) mRNA and protein expression and increased metabolic activity (basal oxygen consumption, proton leak, and maximum respiration). By utilizing this "browning" process, the abundant and accessible WAT stem cell population can be engineered into 3D tissue constructs with the metabolic capacity of native BAT, ultimately for therapeutic intervention in vivo and as a tool for studying BAT and its metabolic properties.

  20. Feasibility of Polycaprolactone Scaffolds Fabricated by Three-Dimensional Printing for Tissue Engineering of Tunica Albuginea

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    Ho Song Yu

    2018-01-01

    Full Text Available Purpose: To investigate the feasibility of a polycaprolactone (PCL scaffold fabricated by three-dimensional (3D printing for tissue engineering applications for tunica albuginea. Materials and Methods: PCL scaffolds were fabricated by use of a 3D printing system. Two scaffolds were fabricated that differed in the architecture of the lay-down pattern: a 90°PCL scaffold and a 45°PCL scaffold. Mechanical properties were measured to compare tensile strength between the two scaffold types. The scaffolds were characterized by scanning electron microscope (SEM images. The scaffolds were seeded with fibroblast cells, and the ability of these scaffolds to support the cells was evaluated by immunofluorescence staining. Results: The PCL scaffolds had well-structured shapes, regular arrays, and good interconnection in SEM images. The horizontal and vertical Young’s modulus coefficients were 13 and 12 MPa for the 90°PCL scaffold and 19 and 21 MPa for the 45°PCL scaffold, respectively. Microscopy images revealed that human fibroblast cells covered the entire scaffold surface. Immunofluorescence staining of ER-TR7 confirmed that the fibroblast cells remained viable and proliferated throughout the time course of the culture. Conclusions: This preliminary study provides experimental evidence for the feasibility of 3D printing of PCL scaffolds for tissue engineering applications of tunica albuginea.

  1. Customized biomimetic scaffolds created by indirect three-dimensional printing for tissue engineering.

    Science.gov (United States)

    Lee, Ju-Yeon; Choi, Bogyu; Wu, Benjamin; Lee, Min

    2013-12-01

    Three-dimensional printing (3DP) is a rapid prototyping technique that can create complex 3D structures by inkjet printing of a liquid binder onto powder biomaterials for tissue engineering scaffolds. Direct fabrication of scaffolds from 3DP, however, imposes a limitation on material choices by manufacturing processes. In this study, we report an indirect 3DP approach wherein a positive replica of desired shapes was printed using gelatin particles, and the final scaffold was directly produced from the printed mold. To create patient-specific scaffolds that match precisely to a patient's external contours, we integrated our indirect 3DP technique with imaging technologies and successfully created custom scaffolds mimicking human mandibular condyle using polycaprolactone and chitosan for potential osteochondral tissue engineering. To test the ability of the technique to precisely control the internal morphology of the scaffolds, we created orthogonal interconnected channels within the scaffolds using computer-aided-design models. Because very few biomaterials are truly osteoinductive, we modified inert 3D printed materials with bioactive apatite coating. The feasibility of these scaffolds to support cell growth was investigated using bone marrow stromal cells (BMSC). The BMSCs showed good viability in the scaffolds, and the apatite coating further enhanced cellular spreading and proliferation. This technique may be valuable for complex scaffold fabrication.

  2. Feasibility of Polycaprolactone Scaffolds Fabricated by Three-Dimensional Printing for Tissue Engineering of Tunica Albuginea.

    Science.gov (United States)

    Yu, Ho Song; Park, Jinju; Lee, Hyun Suk; Park, Su A; Lee, Dong Weon; Park, Kwangsung

    2018-01-01

    To investigate the feasibility of a polycaprolactone (PCL) scaffold fabricated by three-dimensional (3D) printing for tissue engineering applications for tunica albuginea. PCL scaffolds were fabricated by use of a 3D printing system. Two scaffolds were fabricated that differed in the architecture of the lay-down pattern: a 90°PCL scaffold and a 45°PCL scaffold. Mechanical properties were measured to compare tensile strength between the two scaffold types. The scaffolds were characterized by scanning electron microscope (SEM) images. The scaffolds were seeded with fibroblast cells, and the ability of these scaffolds to support the cells was evaluated by immunofluorescence staining. The PCL scaffolds had well-structured shapes, regular arrays, and good interconnection in SEM images. The horizontal and vertical Young's modulus coefficients were 13 and 12 MPa for the 90°PCL scaffold and 19 and 21 MPa for the 45°PCL scaffold, respectively. Microscopy images revealed that human fibroblast cells covered the entire scaffold surface. Immunofluorescence staining of ER-TR7 confirmed that the fibroblast cells remained viable and proliferated throughout the time course of the culture. This preliminary study provides experimental evidence for the feasibility of 3D printing of PCL scaffolds for tissue engineering applications of tunica albuginea. Copyright © 2017 Korean Society for Sexual Medicine and Andrology

  3. Fabrication and Characterization of three dimensional Scaffolds for tissue engineering application via microstereolithography technique

    International Nuclear Information System (INIS)

    Marina Talib; Covington, J.A.; Dove, A.; Bolarinwa, A.; Grover, L.

    2012-01-01

    Microstereolithography is a method used for rapid proto typing of polymeric and ceramic components. This technique converts a computer-aided design (CAD) to a three dimensional (3D) model, and enables layer-per-layer fabrication curing a liquid resin with UV-light or laser source. However, the use of stereo lithography in tissue engineering has not been significantly explored possibly due to the lack of commercially available implantable or biocompatible materials from the SL industry. This study seeks to develop a range of new bio-compatible/degradable materials that are compatible with a commercial 3D direct manufacture system (envisionTEC Desktop). Firstly, a selection of multifunctional polymer and calcium phosphate were studied in order to formulate biodegradable photo polymer resin for specific tissue engineering applications. A 3D structure was successfully fabricated from the formulated photo curable resins. The photo polymer of ceramic suspension was prepared with the addition of 50-70 wt % of calcium pyrophosphate (CPP) and hydroxyapatite (HA). They were then sintered at high temperature for polymer removal, to obtain a ceramic of the desired porosity. Mechanical properties, morphology and calcium phosphate content of the sintered polymers were characterised and investigated with SEM and XRD, respectively. The addition of calcium phosphate coupled with high temperature sintering, had a significant effect on the mechanical properties exhibited by the bio ceramic. The successful fabrication of novel bio ceramic polymer composite with MSL technique offers the possibility of designing complex tissue scaffolds with optimum mechanical properties for specific tissue engineering applications. (author)

  4. Development of an acellular tumor extracellular matrix as a three-dimensional scaffold for tumor engineering.

    Directory of Open Access Journals (Sweden)

    Wei-Dong Lü

    Full Text Available Tumor engineering is defined as the construction of three-dimensional (3D tumors in vitro with tissue engineering approaches. The present 3D scaffolds for tumor engineering have several limitations in terms of structure and function. To get an ideal 3D scaffold for tumor culture, A549 human pulmonary adenocarcinoma cells were implanted into immunodeficient mice to establish xenotransplatation models. Tumors were retrieved at 30-day implantation and sliced into sheets. They were subsequently decellularized by four procedures. Two decellularization methods, Tris-Trypsin-Triton multi-step treatment and sodium dodecyl sulfate (SDS treatment, achieved complete cellular removal and thus were chosen for evaluation of histological and biochemical properties. Native tumor tissues were used as controls. Human breast cancer MCF-7 cells were cultured onto the two 3D scaffolds for further cell growth and growth factor secretion investigations, with the two-dimensional (2D culture and cells cultured onto the Matrigel scaffolds used as controls. Results showed that Tris-Trypsin-Triton multi-step treated tumor sheets had well-preserved extracellular matrix structures and components. Their porosity was increased but elastic modulus was decreased compared with the native tumor samples. They supported MCF-7 cell repopulation and proliferation, as well as expression of growth factors. When cultured within the Tris-Trypsin-Triton treated scaffold, A549 cells and human colorectal adenocarcinoma cells (SW-480 had similar behaviors to MCF-7 cells, but human esophageal squamous cell carcinoma cells (KYSE-510 had a relatively slow cell repopulation rate. This study provides evidence that Tris-Trypsin-Triton treated acellular tumor extracellular matrices are promising 3D scaffolds with ideal spatial arrangement, biomechanical properties and biocompatibility for improved modeling of 3D tumor microenvironments.

  5. Fabrication of three-dimensional porous cell-laden hydrogel for tissue engineering

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Chang Mo; Sant, Shilpa; Masaeli, Mahdokht; Kachouie, Nezamoddin N; Zamanian, Behnam; Khademhosseini, Ali [Center for Biomedical Engineering, Department of Medicine, Brigham and Women' s Hospital, Harvard Medical School, 65 Landsdowne Street, Cambridge, MA 02139 (United States); Lee, Sang-Hoon, E-mail: alik@rics.bwh.harvard.ed [Department of Biomedical Engineering, College of Health Science, Korea University, Jeongneung-dong, Seongbuk-gu, Seoul 136-703 (Korea, Republic of)

    2010-09-15

    For tissue engineering applications, scaffolds should be porous to enable rapid nutrient and oxygen transfer while providing a three-dimensional (3D) microenvironment for the encapsulated cells. This dual characteristic can be achieved by fabrication of porous hydrogels that contain encapsulated cells. In this work, we developed a simple method that allows cell encapsulation and pore generation inside alginate hydrogels simultaneously. Gelatin beads of 150-300 {mu}m diameter were used as a sacrificial porogen for generating pores within cell-laden hydrogels. Gelation of gelatin at low temperature (4 {sup 0}C) was used to form beads without chemical crosslinking and their subsequent dissolution after cell encapsulation led to generation of pores within cell-laden hydrogels. The pore size and porosity of the scaffolds were controlled by the gelatin bead size and their volume ratio, respectively. Fabricated hydrogels were characterized for their internal microarchitecture, mechanical properties and permeability. Hydrogels exhibited a high degree of porosity with increasing gelatin bead content in contrast to nonporous alginate hydrogel. Furthermore, permeability increased by two to three orders while compressive modulus decreased with increasing porosity of the scaffolds. Application of these scaffolds for tissue engineering was tested by encapsulation of hepatocarcinoma cell line (HepG2). All the scaffolds showed similar cell viability; however, cell proliferation was enhanced under porous conditions. Furthermore, porous alginate hydrogels resulted in formation of larger spheroids and higher albumin secretion compared to nonporous conditions. These data suggest that porous alginate hydrogels may have provided a better environment for cell proliferation and albumin production. This may be due to the enhanced mass transfer of nutrients, oxygen and waste removal, which is potentially beneficial for tissue engineering and regenerative medicine applications.

  6. Mapping of Mechanical Strains and Stresses around Quiescent Engineered Three-Dimensional Epithelial Tissues

    Science.gov (United States)

    Gjorevski, Nikolce; Nelson, Celeste M.

    2012-01-01

    Understanding how physical signals guide biological processes requires qualitative and quantitative knowledge of the mechanical forces generated and sensed by cells in a physiologically realistic three-dimensional (3D) context. Here, we used computational modeling and engineered epithelial tissues of precise geometry to define the experimental parameters that are required to measure directly the mechanical stress profile of 3D tissues embedded within native type I collagen. We found that to calculate the stresses accurately in these settings, we had to account for mechanical heterogeneities within the matrix, which we visualized and quantified using confocal reflectance and atomic force microscopy. Using this technique, we were able to obtain traction forces at the epithelium-matrix interface, and to resolve and quantify patterns of mechanical stress throughout the surrounding matrix. We discovered that whereas single cells generate tension by contracting and pulling on the matrix, the contraction of multicellular tissues can also push against the matrix, causing emergent compression. Furthermore, tissue geometry defines the spatial distribution of mechanical stress across the epithelium, which communicates mechanically over distances spanning hundreds of micrometers. Spatially resolved mechanical maps can provide insight into the types and magnitudes of physical parameters that are sensed and interpreted by multicellular tissues during normal and pathological processes. PMID:22828342

  7. Engineering of microscale three-dimensional pancreatic islet models in vitro and their biomedical applications.

    Science.gov (United States)

    Gao, Bin; Wang, Lin; Han, Shuang; Pingguan-Murphy, Belinda; Zhang, Xiaohui; Xu, Feng

    2016-08-01

    Diabetes now is the most common chronic disease in the world inducing heavy burden for the people's health. Based on this, diabetes research such as islet function has become a hot topic in medical institutes of the world. Today, in medical institutes, the conventional experiment platform in vitro is monolayer cell culture. However, with the development of micro- and nano-technologies, several microengineering methods have been developed to fabricate three-dimensional (3D) islet models in vitro which can better mimic the islet of pancreases in vivo. These in vitro islet models have shown better cell function than monolayer cells, indicating their great potential as better experimental platforms to elucidate islet behaviors under both physiological and pathological conditions, such as the molecular mechanisms of diabetes and clinical islet transplantation. In this review, we present the state-of-the-art advances in the microengineering methods for fabricating microscale islet models in vitro. We hope this will help researchers to better understand the progress in the engineering 3D islet models and their biomedical applications such as drug screening and islet transplantation.

  8. Three dimensional extrusion printing induces polymer molecule alignment and cell organization within engineered cartilage.

    Science.gov (United States)

    Guo, Ting; Ringel, Julia P; Lim, Casey G; Bracaglia, Laura G; Noshin, Maeesha; Baker, Hannah B; Powell, Douglas A; Fisher, John P

    2018-04-16

    Proper cell-material interactions are critical to remain cell function and thus successful tissue regeneration. Many fabrication processes have been developed to create microenvironments to control cell attachment and organization on a three-dimensional (3D) scaffold. However, these approaches often involve heavy engineering and only the surface layer can be patterned. We found that 3D extrusion based printing at high temperature and pressure will result an aligned effect on the polymer molecules, and this molecular arrangement will further induce the cell alignment and different differentiation capacities. In particular, articular cartilage tissue is known to have zonal collagen fiber and cell orientation to support different functions, where collagen fibers and chondrocytes align parallel, randomly, and perpendicular, respectively, to the surface of the joint. Therefore, cell alignment was evaluated in a cartilage model in this study. We used small angle X-ray scattering analysis to substantiate the polymer molecule alignment phenomenon. The cellular response was evaluated both in vitro and in vivo. Seeded mesenchymal stem cells (MSCs) showed different morphology and orientation on scaffolds, as a combined result of polymer molecule alignment and printed scaffold patterns. Gene expression results showed improved superficial zonal chondrogenic marker expression in parallel-aligned group. The cell alignment was successfully maintained in the animal model after 7 days with distinct MSC morphology between the casted and parallel printed scaffolds. This 3D printing induced polymer and cell alignment will have a significant impact on developing scaffold with controlled cell-material interactions for complex tissue engineering while avoiding complicated surface treatment, and therefore provides new concept for effective tissue repairing in future clinical applications. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2018. © 2018 Wiley Periodicals, Inc.

  9. Construction of three-dimensional vascularized cardiac tissue with cell sheet engineering.

    Science.gov (United States)

    Sakaguchi, Katsuhisa; Shimizu, Tatsuya; Okano, Teruo

    2015-05-10

    Construction of three-dimensional (3D) tissues with pre-isolated cells is a promising achievement for novel medicine and drug-discovery research. Our laboratory constructs 3D tissues with an innovative and unique method for layering multiple cell sheets. Cell sheets maintain a high-efficiently regenerating function, because of the higher cell density and higher transplantation efficiency, compared to other cell-delivery methods. Cell sheets have already been applied in clinical applications for regenerative medicine in treating patients with various diseases. Therefore, in our search to develop a more efficient treatment with cell sheets, we are constructing 3D tissues by layering cell sheets. Native animal tissues and organs have an abundance of capillaries to supply oxygen and nutrients, and to remove waste molecules. In our investigation of vascularized cardiac cell sheets, we have found that endothelial cells within cell sheets spontaneously form blood vessel networks as in vivo capillaries. To construct even thicker 3D tissues by layering multiple cell sheets, it is critical to have a medium or blood flow within the vascular networks of the cell sheets. Therefore, to perfuse medium or blood in the cell sheet vascular network to maintain the viability of all cells, we developed two types of vascular beds; (1) a femoral muscle-based vascular bed, and (2) a synthetic collagen gel-based vascular bed. Both vascular beds successfully provide the critical flow of culture medium, which allows 12-layer cell sheets to survive. Such bioreactor systems, when combined with cell sheet engineering techniques, have produced functional vascularized 3D tissues. Here we explain and discuss the various processes to obtain vascular networks by properly connecting cell sheets and the engineering of 3D tissues. Copyright © 2014 Elsevier B.V. All rights reserved.

  10. Biomimetics of the extracellular matrix: an integrated three-dimensional fiber-hydrogel composite for cartilage tissue engineering

    NARCIS (Netherlands)

    Coburn, J.; Gibson, M.; Bandalini, P.A.; Laird, C.; Mao, H.Q.; Moroni, Lorenzo; Seliktar, D.; Elisseeff, J.H.

    2011-01-01

    The native extracellular matrix (ECM) consists of an integrated fibrous protein network and proteoglycan-based ground (hydrogel) substance. We designed a novel electrospinning technique to engineer a three dimensional fiber-hydrogel composite that mimics the native ECM structure, is injectable, and

  11. Three-dimensional printing of porous ceramic scaffolds for bone tissue engineering.

    Science.gov (United States)

    Seitz, Hermann; Rieder, Wolfgang; Irsen, Stephan; Leukers, Barbara; Tille, Carsten

    2005-08-01

    This article reports a new process chain for custom-made three-dimensional (3D) porous ceramic scaffolds for bone replacement with fully interconnected channel network for the repair of osseous defects from trauma or disease. Rapid prototyping and especially 3D printing is well suited to generate complex-shaped porous ceramic matrices directly from powder materials. Anatomical information obtained from a patient can be used to design the implant for a target defect. In the 3D printing technique, a box filled with ceramic powder is printed with a polymer-based binder solution layer by layer. Powder is bonded in wetted regions. Unglued powder can be removed and a ceramic green body remains. We use a modified hydroxyapatite (HA) powder for the fabrication of 3D printed scaffolds due to the safety of HA as biocompatible implantable material and efficacy for bone regeneration. The printed ceramic green bodies are consolidated at a temperature of 1250 degrees C in a high temperature furnace in ambient air. The polymeric binder is pyrolysed during sintering. The resulting scaffolds can be used in tissue engineering of bone implants using patient-derived cells that are seeded onto the scaffolds. This article describes the process chain, beginning from data preparation to 3D printing tests and finally sintering of the scaffold. Prototypes were successfully manufactured and characterized. It was demonstrated that it is possible to manufacture parts with inner channels with a dimension down to 450 microm and wall structures with a thickness down to 330 microm. The mechanical strength of dense test parts is up to 22 MPa. Copyright 2005 Wiley Periodicals, Inc.

  12. Rapid fabrication system for three-dimensional tissues using cell sheet engineering and centrifugation.

    Science.gov (United States)

    Hasegawa, Akiyuki; Haraguchi, Yuji; Shimizu, Tatsuya; Okano, Teruo

    2015-12-01

    Three-dimensional (3D) tissues can be reconstructed by cell sheet technology, and various clinical researches using these constructed tissues have already been initiated to regenerate damaged tissues. While 3D tissues can be easily fabricated by layering cell sheets, the attachment period for cell adhesion between a cell sheet and a culture dish, or double-layered cell sheets normally takes 20-30 min. This study proposed a more rapid fabrication system for bioengineered tissue using cell sheet technology and centrifugation. A C2C12 mouse myoblast sheet harvested from a temperature-responsive culture dish will attach tightly to a culture dish or another cell sheet at 37°C after a 20 min-incubation. However, the same cell sheet centrifuged (12-34 × g) for 3 min also attached tightly to a dish or another cell sheet at 37°C after only a 3 min-incubation. The manipulation time was reduced by approximately two-thirds by centrifugation. The rapid attachments were also cross-sectionally confirmed by optical coherence tomography. These rapidly constructed cell sheet-tissues using centrifugation showed active cell metabolism, cell viability, and very high production of vascular endothelial growth factor, like those prepared by the conventional method; indicating complete cell sheet-attachment without any cell damage. This new system will be a powerful tool in the fields of cell sheet-based tissue engineering and regenerative medicine, and accelerate the use of cell sheets in clinical applications. © 2015 Wiley Periodicals, Inc.

  13. Engineering three-dimensional stem cell morphogenesis for the development of tissue models and scalable regenerative therapeutics.

    Science.gov (United States)

    Kinney, Melissa A; Hookway, Tracy A; Wang, Yun; McDevitt, Todd C

    2014-02-01

    The physiochemical stem cell microenvironment regulates the delicate balance between self-renewal and differentiation. The three-dimensional assembly of stem cells facilitates cellular interactions that promote morphogenesis, analogous to the multicellular, heterotypic tissue organization that accompanies embryogenesis. Therefore, expansion and differentiation of stem cells as multicellular aggregates provides a controlled platform for studying the biological and engineering principles underlying spatiotemporal morphogenesis and tissue patterning. Moreover, three-dimensional stem cell cultures are amenable to translational screening applications and therapies, which underscores the broad utility of scalable suspension cultures across laboratory and clinical scales. In this review, we discuss stem cell morphogenesis in the context of fundamental biophysical principles, including the three-dimensional modulation of adhesions, mechanics, and molecular transport and highlight the opportunities to employ stem cell spheroids for tissue modeling, bioprocessing, and regenerative therapies.

  14. Analytical three-dimensional neutron transport benchmarks for verification of nuclear engineering codes. Final report

    International Nuclear Information System (INIS)

    Ganapol, B.D.; Kornreich, D.E.

    1997-01-01

    Because of the requirement of accountability and quality control in the scientific world, a demand for high-quality analytical benchmark calculations has arisen in the neutron transport community. The intent of these benchmarks is to provide a numerical standard to which production neutron transport codes may be compared in order to verify proper operation. The overall investigation as modified in the second year renewal application includes the following three primary tasks. Task 1 on two dimensional neutron transport is divided into (a) single medium searchlight problem (SLP) and (b) two-adjacent half-space SLP. Task 2 on three-dimensional neutron transport covers (a) point source in arbitrary geometry, (b) single medium SLP, and (c) two-adjacent half-space SLP. Task 3 on code verification, includes deterministic and probabilistic codes. The primary aim of the proposed investigation was to provide a suite of comprehensive two- and three-dimensional analytical benchmarks for neutron transport theory applications. This objective has been achieved. The suite of benchmarks in infinite media and the three-dimensional SLP are a relatively comprehensive set of one-group benchmarks for isotropically scattering media. Because of time and resource limitations, the extensions of the benchmarks to include multi-group and anisotropic scattering are not included here. Presently, however, enormous advances in the solution for the planar Green's function in an anisotropically scattering medium have been made and will eventually be implemented in the two- and three-dimensional solutions considered under this grant. Of particular note in this work are the numerical results for the three-dimensional SLP, which have never before been presented. The results presented were made possible only because of the tremendous advances in computing power that have occurred during the past decade

  15. Analytical three-dimensional neutron transport benchmarks for verification of nuclear engineering codes. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Ganapol, B.D.; Kornreich, D.E. [Univ. of Arizona, Tucson, AZ (United States). Dept. of Nuclear Engineering

    1997-07-01

    Because of the requirement of accountability and quality control in the scientific world, a demand for high-quality analytical benchmark calculations has arisen in the neutron transport community. The intent of these benchmarks is to provide a numerical standard to which production neutron transport codes may be compared in order to verify proper operation. The overall investigation as modified in the second year renewal application includes the following three primary tasks. Task 1 on two dimensional neutron transport is divided into (a) single medium searchlight problem (SLP) and (b) two-adjacent half-space SLP. Task 2 on three-dimensional neutron transport covers (a) point source in arbitrary geometry, (b) single medium SLP, and (c) two-adjacent half-space SLP. Task 3 on code verification, includes deterministic and probabilistic codes. The primary aim of the proposed investigation was to provide a suite of comprehensive two- and three-dimensional analytical benchmarks for neutron transport theory applications. This objective has been achieved. The suite of benchmarks in infinite media and the three-dimensional SLP are a relatively comprehensive set of one-group benchmarks for isotropically scattering media. Because of time and resource limitations, the extensions of the benchmarks to include multi-group and anisotropic scattering are not included here. Presently, however, enormous advances in the solution for the planar Green`s function in an anisotropically scattering medium have been made and will eventually be implemented in the two- and three-dimensional solutions considered under this grant. Of particular note in this work are the numerical results for the three-dimensional SLP, which have never before been presented. The results presented were made possible only because of the tremendous advances in computing power that have occurred during the past decade.

  16. Three dimensional graphene scaffold for cardiac tissue engineering and in-situ electrical recording.

    Science.gov (United States)

    Ameri, S K; Singh, P K; D'Angelo, R; Stoppel, W; Black, L; Sonkusale, S R

    2016-08-01

    In this paper, we present a three-dimensional graphene foam made of few layers of CVD grown graphene as a scaffold for growing cardiac cells and recording their electrical activity. Our results show that graphene foam not only provides an excellent extra-cellular matrix (ECM) for the culture of such electrogenic cells but also enables recording of its extracellular electrical activity in-situ. Recording is possible due to graphene's excellent conductivity. In this paper, we present our results on the fabrication of the graphene scaffold and initial studies on the culture of cardiac cell lines such as HL-1 and recording of their real-time electrical activity.

  17. Transient Three-Dimensional Analysis of Side Load in Liquid Rocket Engine Nozzles

    Science.gov (United States)

    Wang, Ten-See

    2004-01-01

    Three-dimensional numerical investigations on the nozzle start-up side load physics were performed. The objective of this study is to identify the three-dimensional side load physics and to compute the associated aerodynamic side load using an anchored computational methodology. The computational methodology is based on an unstructured-grid, and pressure-based computational fluid dynamics formulation, and a simulated inlet condition based on a system calculation. Finite-rate chemistry was used throughout the study so that combustion effect is always included, and the effect of wall cooling on side load physics is studied. The side load physics captured include the afterburning wave, transition from free- shock to restricted-shock separation, and lip Lambda shock oscillation. With the adiabatic nozzle, free-shock separation reappears after the transition from free-shock separation to restricted-shock separation, and the subsequent flow pattern of the simultaneous free-shock and restricted-shock separations creates a very asymmetric Mach disk flow. With the cooled nozzle, the more symmetric restricted-shock separation persisted throughout the start-up transient after the transition, leading to an overall lower side load than that of the adiabatic nozzle. The tepee structures corresponding to the maximum side load were addressed.

  18. Analysis of tooth movement in extraction cases using three-dimensional reverse engineering technology.

    Science.gov (United States)

    Cha, Bong Kuen; Lee, Jae Yong; Jost-Brinkmann, Paul-Georg; Yoshida, Noriaki

    2007-08-01

    Despite inherent errors, cephalometric superimpositions are currently the most widely used means for assessing sagittal and vertical tooth movements. The purpose of this study was to compare three-dimensional (3D) digital model superimposition with cephalometric superimposition. The material was collected from initial and final maxillary casts and lateral cephalometric radiographs of 30 patients (6 males, 24 females, mean age 17.7 years) who underwent orthodontic treatment with extraction of permanent teeth. Each pair of cephalograms was traced and superimposed according to Ricketts' four-step method. 3D scanning of the maxillary dental casts was performed using INUS dental scanning solution(R), which consists of a 3D scanner, an autoscan system, and 3D reverse modelling software. The 3D superimposition was carried out using the surface-to-surface matching (best-fit method) function of the autoscan system. The antero-posterior movement of the maxillary first molar and central incisor was evaluated cephalometrically and on 3D digital models. To determine whether any difference existed between the two measuring techniques, paired t-tests and correlation analysis were undertaken. The results revealed no statistical differences between the mean incisor and molar movements as assessed cephalometrically or by 3D model superimposition. These findings suggest that the 3D digital orthodontic model superimposition technique used in this study is clinically as reliable as cephalometric superimposition for assessing orthodontic tooth movements.

  19. An inviscid three-dimensional analysis of the Space Shuttle main engine hot-gas manifold

    Science.gov (United States)

    Liang, P. Y.

    1983-01-01

    A numerical study using an inviscid three-dimensional Lagrangian fluid dynamics code has been conducted as a part of an overall effort to understand the flow behavior in the SSME fuel side hot-gas manifold. The model simulates flow from the high-pressure fuel turbine exit through the transfer ducts, including the effects of swirl, inlet flow symmetry, and presence of straightening vanes and struts; a separate, more-detailed effort is in progress that includes viscosity and turbulence effects. The simplified model presented is divided into two parts, the first includes the 180-degree turnaround duct downstream of the turbine exit and the spherical fuel bowl section, while the second models the three transfer ducts. The two parts of the model are coupled together with the interface conditions being updated through iteration. Results indicate that a transverse pressure differential of 165 psi would be imposed on the turbine exit and that unstable flow separation occurs around the vanes, struts, and within the transfer ducts. The three transfer ducts show a mass flux split of approximately 41, 21, and 38 percent. Results to date are encouraging that certain flow characteristics can be usefuly represented using a relatively coarse grid inviscid code.

  20. A Versatile Method for Fabricating Tissue Engineering Scaffolds with a Three-Dimensional Channel for Prevasculature Networks.

    Science.gov (United States)

    Li, Shuai; Liu, Yuan-Yuan; Liu, Li-Jun; Hu, Qing-Xi

    2016-09-28

    Despite considerable advances in tissue engineering over the past two decades, solutions to some crucial problems remain elusive. Vascularization is one of the most important factors that greatly influence the function of scaffolds. Many research studies have focused on the construction of a vascular-like network with prevascularization structure. Sacrificial materials are widely used to build perfusable vascular-like architectures, but most of these fabricated scaffolds only have a 2D plane-connected network. The fabrication of three-dimensional perfusable branched networks remains an urgent issue. In this work, we developed a novel sacrificial molding technique for fabricating biocompatible scaffolds with a three-dimensional perfusable branched network. Here, 3D-printed poly(vinyl alcohol) (PVA) filament was used as the sacrificial material. The fused PVA was deposited on the surface of a cylinder to create the 3D branched solid network. Gelatin was used to embed the solid network. Then, the PVA mold was dissolved after curing the hydrogel. The obtained architecture shows good perfusability. Cell experiment results indicated that human umbilical vein endothelial cells (HUVECs) successfully attached to the surface of the branched channel and maintained high viability after a few days in culture. In order to prevent deformation of the channel, paraffin was coated on the surface of the printed structure, and hydroxyapatite (HA) was added to gelatin. In conclusion, we demonstrate a novel strategy toward the engineering of prevasculature thick tissues through the integration of the fused PVA filament deposit. This approach has great potential in solving the issue of three-dimensional perfusable branched networks and opens the way to clinical applications.

  1. Whole-organ tissue engineering: decellularization and recellularization of three-dimensional matrix liver scaffolds.

    Science.gov (United States)

    Sabetkish, Shabnam; Kajbafzadeh, Abdol-Mohammad; Sabetkish, Nastaran; Khorramirouz, Reza; Akbarzadeh, Aram; Seyedian, Sanam Ladi; Pasalar, Parvin; Orangian, Saghar; Beigi, Reza Seyyed Hossein; Aryan, Zahra; Akbari, Hesam; Tavangar, Seyyed Mohammad

    2015-04-01

    To report the results of whole liver decellularization by two different methods. To present the results of grafting rat and sheep decellularized liver matrix (DLM) into the normal rat liver and compare natural cell seeding process in homo/xenograft of DLM. To compare the results of in vitro whole liver recellularization with rats' neonatal green fluorescent protein (GFP)-positive hepatic cells with outcomes of in vivo recellularization process. Whole liver of 8 rats and 4 sheep were resected and cannulated via the hepatic vein and perfused with sodium dodecyl sulfate (SDS) or Triton + SDS. Several examinations were performed to compare the efficacy of these two decellularization procedures. In vivo recellularization of sheep and rat DLMs was performed following transplantation of multiple pieces of both scaffolds in the subhepatic area of four rats. To compare the efficacy of different scaffolds in autologous cell seeding, biopsies of homograft and xenograft were assessed 8 weeks postoperatively. Whole DLMs of 4 rats were also recellularized in vitro by perfusion of rat's fetal GFP-positive hepatic cells with pulsatile bioreactor. Histological evaluation and enzymatic assay were performed for both in vivo and in vitro recellularized samples. The results of this study demonstrated that the triton method was a promising decellularization approach for preserving the three-dimensional structure of liver. In vitro recellularized DLMs were more similar to natural ones compared with in vivo recellularized livers. However, homografts showed better characteristics with more organized structure compared with xenografts. In vitro recellularization of liver scaffolds with autologous cells represents an attractive prospective for regeneration of liver as one of the most compound organs. In vivo cell seeding on the scaffold of the same species may have more satisfactory outcomes when compared with the results of xenotransplantation. This study theoretically may pave the road for

  2. Transient Three-Dimensional Analysis of Nozzle Side Load in Regeneratively Cooled Engines

    Science.gov (United States)

    ng, Ten-See

    2005-01-01

    Nozzle side loads are potentially detrimental to the integrity and life of almost all launch vehicles. the lack of a detailed prediction capability results in reducing life and increased weight for reusable nozzle systems. A clear understanding of the mechanism that contribute to side loads during engine startup, shutdown, and steady-state operations must be established. A CFD based predictive tool must be developed to aid the understanding of side load physics and development of future reusable engine.

  3. Three-dimensional simulation of a novel rotary-piston engine in the motoring mode

    Directory of Open Access Journals (Sweden)

    Mohammadreza Khani

    2017-09-01

    Full Text Available In this simulation study, the flow and thermal characteristics of a novel rotary-piston engine, which is a kind of internal combustion engines, were investigated by computational fluid dynamics and the finite volume method. The structure of this engine is different to others, mainly for having 24 cylinders during the motoring mode. As a novel engine, creation of numerical models based on Reynolds average Navier Stokes (RANS simulation and analysis of various speed engines on the flow and thermal fields during intake and compression strokes are the focus of this work. The results were illustrated in term of the streamline patterns, in-cylinder temperature and pressure profile, swirl ratio (SR, wall heat flux, and turbulent velocity fluctuation. The present study indicates that, the mean pressure, temperature trace, and heat loss from the wall increase when switching to a higher engine speed. The temperature distribution reveals that the maximum temperature is restricted in the center of the combustion chamber near top dead center (TDC. Also, the maximum amount of turbulent velocity and swirl ratio are achieved at the beginning of the intake stroke and near TDC. It is observed that the obtained numerical results are in general agreement with the available experimental data.

  4. Microporous membrane-based liver tissue engineering for the reconstruction of three-dimensional functional liver tissues in vitro.

    Science.gov (United States)

    Kasuya, Junichi; Tanishita, Kazuo

    2012-01-01

    To meet the increasing demand for liver tissue engineering, various three-dimensional (3D) liver cell culture techniques have been developed. Nevertheless, conventional liver cell culture techniques involving the suspending cells in extracellular matrix (ECM) components and the seeding of cells into 3D biodegradable scaffolds have an intrinsic shortcoming, low cell-scaffold ratios. We have developed a microporous membrane-based liver cell culture technique. Cell behaviors and tissue organization can be controlled by membrane geometry, and cell-dense thick tissues can be reconstructed by layering cells cultured on biodegradable microporous membranes. Applications extend from liver parenchymal cell monoculture to multi-cell type cultures for the reconstruction of 3D functional liver tissue. This review focuses on the expanding role for microporous membranes in liver tissue engineering, primarily from our research.

  5. A biomimetic three-dimensional woven composite scaffold for functional tissue engineering of cartilage

    Science.gov (United States)

    Moutos, Franklin T.; Freed, Lisa E.; Guilak, Farshid

    2007-02-01

    Tissue engineering seeks to repair or regenerate tissues through combinations of implanted cells, biomaterial scaffolds and biologically active molecules. The rapid restoration of tissue biomechanical function remains an important challenge, emphasizing the need to replicate structural and mechanical properties using novel scaffold designs. Here we present a microscale 3D weaving technique to generate anisotropic 3D woven structures as the basis for novel composite scaffolds that are consolidated with a chondrocyte-hydrogel mixture into cartilage tissue constructs. Composite scaffolds show mechanical properties of the same order of magnitude as values for native articular cartilage, as measured by compressive, tensile and shear testing. Moreover, our findings showed that porous composite scaffolds could be engineered with initial properties that reproduce the anisotropy, viscoelasticity and tension-compression nonlinearity of native articular cartilage. Such scaffolds uniquely combine the potential for load-bearing immediately after implantation in vivo with biological support for cell-based tissue regeneration without requiring cultivation in vitro.

  6. Three-Dimensional Characterization of Tissue-Engineered Constructs by Contrast-Enhanced Nanofocus Computed Tomography

    OpenAIRE

    Papantoniou, Ioannis; Sonnaert, Maarten; Geris, Liesbet; Luyten, Frank P.; Schrooten, Jan; Kerckhofs, Greet

    2014-01-01

    To successfully implement tissue-engineered (TE) constructs as part of a clinical therapy, it is necessary to develop quality control tools that will ensure accurate and consistent TE construct release specifications. Hence, advanced methods to monitor TE construct properties need to be further developed. In this study, we showed proof of concept for contrast-enhanced nanofocus computed tomography (CE-nano-CT) as a whole-construct imaging technique with a noninvasive potential that enables th...

  7. Three-dimensional chitosan-nanohydroxyapatite composite scaffolds for bone tissue engineering

    Science.gov (United States)

    Thein-Han, W. W.; Misra, R. D. K.

    2009-09-01

    We describe the structure of biodegradable chitosan-nanohydroxyapatite (nHA) composites scaffolds and their interaction with pre-osteoblasts for bone tissue engineering. The scaffolds were fabricated via freezing and lyophilization. The nanocomposite scaffolds were characterized by a highly porous structure and pore size of ˜50-125 μm, irrespective of nHA content. The observed significant enhancement in the biological response of pre-osteoblast on nanocomposite scaffolds expressed in terms of cell attachment, proliferation, and widespread morphology in relation to pure chitosan points toward their potential use as scaffold material for bone regeneration.

  8. Direct E-jet printing of three-dimensional fibrous scaffold for tendon tissue engineering.

    Science.gov (United States)

    Wu, Yang; Wang, Zuyong; Ying Hsi Fuh, Jerry; San Wong, Yoke; Wang, Wilson; San Thian, Eng

    2017-04-01

    Tissue engineering (TE) offers a promising strategy to restore diseased tendon tissue. However, a suitable scaffold for tendon TE has not been achieved with current fabrication techniques. Herein, we report the development of a novel electrohydrodynamic jet printing (E-jetting) for engineering 3D tendon scaffold with high porosity and orientated micrometer-size fibers. The E-jetted scaffold comprised tubular multilayered micrometer-size fibrous bundles, with interconnected spacing and geometric anisotropy along the longitudinal direction of the scaffold. Fiber diameter, stacking pattern, and interfiber distance have been observed to affect the structural stability of the scaffold, of which the enhanced mechanical strength can be obtained for scaffolds with thick fibers as the supporting layer. Human tenocytes showed a significant increase in cellular metabolism on the E-jetted scaffolds as compared to that on conventional electrospun scaffolds (2.7-, 2.8-, and 3.1-fold increase for 150, 300, and 600 µm interfiber distance, respectively; p 3D fibrous scaffold to promote organized tissue reconstruction for potential tendon healing. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 616-627, 2017. © 2015 Wiley Periodicals, Inc.

  9. A highly organized three-dimensional alginate scaffold for cartilage tissue engineering prepared by microfluidic technology.

    Science.gov (United States)

    Wang, Chen-Chie; Yang, Kai-Chiang; Lin, Keng-Hui; Liu, Hwa-Chang; Lin, Feng-Huei

    2011-10-01

    Osteoarthritis is a degenerative disease and frequently involves the knee, hip and phalangeal joints. Current treatments used in small cartilage defects including multiple drilling, abrasion arthroplasty, mosaicplasty, and autogenous chondrocyte transplantation, however, there are problems needed to be solved. The standard treatment for severe osteoarthritis is total joint arthroplasty. The disadvantages of this surgery are the possibility of implant loosening. Therefore, tissue engineering for cartilage regeneration has become a promising topic. We have developed a new method to produce a highly organized single polymer (alginate) scaffold using microfluidic device. Scanning electron microscope and confocal fluoroscope examinations showed that the scaffold has a regular interconnected porous structure in the scale of 250 μm and high porosity. The scaffold is effective in chondrocyte culture; the cell viability test (WST-1 assay), cell toxicity (lactate dehydrogenase assay), cell survival rate, extracellular matrix production (glycosaminoglycans contents), cell proliferation (DNA quantification), and gene expression (real-time PCR) all revealed good results for chondrocyte culture. The chondrocytes can maintain normal phenotypes, highly express aggrecan and type II collagen, and secrete a great deal of extracellular matrix when seeded in the alginate scaffold. This study demonstrated that a highly organized alginate scaffold can be prepared with an economical microfluidic device, and this scaffold is effective in cartilage tissue engineering. Crown Copyright © 2011. Published by Elsevier Ltd. All rights reserved.

  10. Three-Dimensional Supermacroporous Carrageenan-Gelatin Cryogel Matrix for Tissue Engineering Applications

    Directory of Open Access Journals (Sweden)

    Archana Sharma

    2013-01-01

    Full Text Available A tissue-engineered polymeric scaffold should provide suitable macroporous structure similar to that of extracellular matrix which can induce cellular activities and guide tissue regeneration. Cryogelation is a technique in which appropriate monomers or polymeric precursors frozen at sub-zero temperature leads to the formation of supermacroporous cryogel matrices. In this study carrageenan-gelatin (natural polymers cryogels were synthesized by using glutaraldehyde and 1-ethyl-3-[3-dimethylaminopropyl] carbodiimide hydrochloride and N-hydroxysuccinimide (EDC-NHS as crosslinking agent at optimum concentrations. Matrices showed large and interconnected pores which were in the range of 60–100 μm diameter. Unconfined compression analysis showed elasticity and physical integrity of all cryogels, as these matrices regained their original length after 90% compressing from the original size. Moreover Young’s modulus was found to be in the range of 4–11 kPa for the dry cryogel sections. These cryogels also exhibited good in vitro degradation capacity at 37 °C within 4 weeks of incubation. Supermacroporous carrageenan-gelatin cryogels showed efficient cell adherence and proliferation of Cos-7 cells which was examined by SEM. PI nuclear stain was used to observe cell-matrix interaction. Cytotoxicity of the scaffolds was checked by MTT assay which showed that cryogels are biocompatible and act as a potential material for tissue engineering and regenerative medicine.

  11. The Development of Three Dimensional (3D) Fabrication Apparatus for Tissue Engineering Application

    International Nuclear Information System (INIS)

    Marina Talib

    2015-01-01

    Microstereolithography has been chosen as a means for the creation of 3D tissue scaffolds. It offers a unique way to precisely control matrix architecture including size, shape, inter connectivity, branching, geometry and orientation, which will yield biomimetic structures varying in design and material composition. This paper discussed the development of stereo lithography apparatus. This allowed some understanding of the process to be achieved, with small volumes of test material, before moving to a commercialised setup. The equipment's developed in this project was a UV light engine. This development involved modification of a high power ultra-bright LED device, which emits light at wavelengths similar to the Envisiontec Desktop projector (365 nm). (author)

  12. Rapid Engineering of Three-Dimensional, Multicellular Tissues With Polymeric Scaffolds

    Science.gov (United States)

    Gonda, Steve R.; Jordan, Jacqueline; Fraga, Denise N.

    2007-01-01

    A process has been developed for the rapid tissue engineering of multicellular-tissue-equivalent assemblies by the controlled enzymatic degradation of polymeric beads in a low-fluid-shear bioreactor. In this process, the porous polymeric beads serve as temporary scaffolds to support the assemblies of cells in a tissuelike 3D configuration during the critical initial growth phases of attachment of anchorage-dependent cells, aggregation of the cells, and formation of a 3D extracellular matrix. Once the cells are assembled into a 3D array and enmeshed in a structural supportive 3D extracellular matrix (ECM), the polymeric scaffolds can be degraded in the low-fluid-shear environment of the NASA-designed bioreactor. The natural 3D tissuelike assembly, devoid of any artificial support structure, is maintained in the low-shear bioreactor environment by the newly formed natural cellular/ECM. The elimination of the artificial scaffold allows normal tissue structure and function.

  13. ADFNE: Open source software for discrete fracture network engineering, two and three dimensional applications

    Science.gov (United States)

    Fadakar Alghalandis, Younes

    2017-05-01

    Rapidly growing topic, the discrete fracture network engineering (DFNE), has already attracted many talents from diverse disciplines in academia and industry around the world to challenge difficult problems related to mining, geothermal, civil, oil and gas, water and many other projects. Although, there are few commercial software capable of providing some useful functionalities fundamental for DFNE, their costs, closed code (black box) distributions and hence limited programmability and tractability encouraged us to respond to this rising demand with a new solution. This paper introduces an open source comprehensive software package for stochastic modeling of fracture networks in two- and three-dimension in discrete formulation. Functionalities included are geometric modeling (e.g., complex polygonal fracture faces, and utilizing directional statistics), simulations, characterizations (e.g., intersection, clustering and connectivity analyses) and applications (e.g., fluid flow). The package is completely written in Matlab scripting language. Significant efforts have been made to bring maximum flexibility to the functions in order to solve problems in both two- and three-dimensions in an easy and united way that is suitable for beginners, advanced and experienced users.

  14. Three-dimensional computer-aided human factors engineering analysis of a grafting robot.

    Science.gov (United States)

    Chiu, Y C; Chen, S; Wu, G J; Lin, Y H

    2012-07-01

    The objective of this research was to conduct a human factors engineering analysis of a grafting robot design using computer-aided 3D simulation technology. A prototype tubing-type grafting robot for fruits and vegetables was the subject of a series of case studies. To facilitate the incorporation of human models into the operating environment of the grafting robot, I-DEAS graphic software was applied to establish individual models of the grafting robot in line with Jack ergonomic analysis. Six human models (95th percentile, 50th percentile, and 5th percentile by height for both males and females) were employed to simulate the operating conditions and working postures in a real operating environment. The lower back and upper limb stresses of the operators were analyzed using the lower back analysis (LBA) and rapid upper limb assessment (RULA) functions in Jack. The experimental results showed that if a leg space is introduced under the robot, the operator can sit closer to the robot, which reduces the operator's level of lower back and upper limbs stress. The proper environmental layout for Taiwanese operators for minimum levels of lower back and upper limb stress are to set the grafting operation at 23.2 cm away from the operator at a height of 85 cm and with 45 cm between the rootstock and scion units.

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

    Science.gov (United States)

    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. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Three-Dimensional Human iPSC-Derived Artificial Skeletal Muscles Model Muscular Dystrophies and Enable Multilineage Tissue Engineering

    Directory of Open Access Journals (Sweden)

    Sara Martina Maffioletti

    2018-04-01

    Full Text Available Summary: Generating human skeletal muscle models is instrumental for investigating muscle pathology and therapy. Here, we report the generation of three-dimensional (3D artificial skeletal muscle tissue from human pluripotent stem cells, including induced pluripotent stem cells (iPSCs from patients with Duchenne, limb-girdle, and congenital muscular dystrophies. 3D skeletal myogenic differentiation of pluripotent cells was induced within hydrogels under tension to provide myofiber alignment. Artificial muscles recapitulated characteristics of human skeletal muscle tissue and could be implanted into immunodeficient mice. Pathological cellular hallmarks of incurable forms of severe muscular dystrophy could be modeled with high fidelity using this 3D platform. Finally, we show generation of fully human iPSC-derived, complex, multilineage muscle models containing key isogenic cellular constituents of skeletal muscle, including vascular endothelial cells, pericytes, and motor neurons. These results lay the foundation for a human skeletal muscle organoid-like platform for disease modeling, regenerative medicine, and therapy development. : Maffioletti et al. generate human 3D artificial skeletal muscles from healthy donors and patient-specific pluripotent stem cells. These human artificial muscles accurately model severe genetic muscle diseases. They can be engineered to include other cell types present in skeletal muscle, such as vascular cells and motor neurons. Keywords: skeletal muscle, pluripotent stem cells, iPS cells, myogenic differentiation, tissue engineering, disease modeling, muscular dystrophy, organoids

  17. Collagen density gradient on three-dimensional printed poly(ε-caprolactone) scaffolds for interface tissue engineering.

    Science.gov (United States)

    D'Amora, Ugo; D'Este, Matteo; Eglin, David; Safari, Fatemeh; Sprecher, Christoph M; Gloria, Antonio; De Santis, Roberto; Alini, Mauro; Ambrosio, Luigi

    2018-02-01

    The ability to engineer scaffolds that resemble the transition between tissues would be beneficial to improve repair of complex organs, but has yet to be achieved. In order to mimic tissue organization, such constructs should present continuous gradients of geometry, stiffness and biochemical composition. Although the introduction of rapid prototyping or additive manufacturing techniques allows deposition of heterogeneous layers and shape control, the creation of surface chemical gradients has not been explored on three-dimensional (3D) scaffolds obtained through fused deposition modelling technique. Thus, the goal of this study was to introduce a gradient functionalization method in which a poly(ε-caprolactone) surface was first aminolysed and subsequently covered with collagen via carbodiimide reaction. The 2D constructs were characterized for their amine and collagen contents, wettability, surface topography and biofunctionality. Finally, chemical gradients were created in 3D printed scaffolds with controlled geometry and porosity. The combination of additive manufacturing and surface modification is a viable tool for the fabrication of 3D constructs with controlled structural and chemical gradients. These constructs can be employed for mimicking continuous tissue gradients for interface tissue engineering. Copyright © 2017 John Wiley & Sons, Ltd.

  18. Volumetric Analysis of Alveolar Bone Defect Using Three-Dimensional-Printed Models Versus Computer-Aided Engineering.

    Science.gov (United States)

    Du, Fengzhou; Li, Binghang; Yin, Ningbei; Cao, Yilin; Wang, Yongqian

    2017-03-01

    Knowing the volume of a graft is essential in repairing alveolar bone defects. This study investigates the 2 advanced preoperative volume measurement methods: three-dimensional (3D) printing and computer-aided engineering (CAE). Ten unilateral alveolar cleft patients were enrolled in this study. Their computed tomographic data were sent to 3D printing and CAE software. A simulated graft was used on the 3D-printed model, and the graft volume was measured by water displacement. The volume calculated by CAE software used mirror-reverses technique. The authors compared the actual volumes of the simulated grafts with the CAE software-derived volumes. The average volume of the simulated bone grafts by 3D-printed models was 1.52 mL, higher than the mean volume of 1.47 calculated by CAE software. The difference between the 2 volumes was from -0.18 to 0.42 mL. The paired Student t test showed no statistically significant difference between the volumes derived from the 2 methods. This study demonstrated that the mirror-reversed technique by CAE software is as accurate as the simulated operation on 3D-printed models in unilateral alveolar cleft patients. These findings further validate the use of 3D printing and CAE technique in alveolar defect repairing.

  19. Three-Dimensionally Engineered Normal Human Broncho-epithelial Tissue-Like Assemblies: Target Tissues for Human Respiratory Viral Infections

    Science.gov (United States)

    Goodwin, T. J.; McCarthy, M.; Lin, Y-H

    2006-01-01

    In vitro three-dimensional (3D) human broncho-epithelial (HBE) tissue-like assemblies (3D HBE TLAs) from this point forward referred to as TLAs were engineered in Rotating Wall Vessel (RWV) technology to mimic the characteristics of in vivo tissues thus providing a tool to study human respiratory viruses and host cell interactions. The TLAs were bioengineered onto collagen-coated cyclodextran microcarriers using primary human mesenchymal bronchial-tracheal cells (HBTC) as the foundation matrix and an adult human bronchial epithelial immortalized cell line (BEAS-2B) as the overlying component. The resulting TLAs share significant characteristics with in vivo human respiratory epithelium including polarization, tight junctions, desmosomes, and microvilli. The presence of tissue-like differentiation markers including villin, keratins, and specific lung epithelium markers, as well as the production of tissue mucin, further confirm these TLAs differentiated into tissues functionally similar to in vivo tissues. Increasing virus titers for human respiratory syncytial virus (wtRSVA2) and parainfluenza virus type 3 (wtPIV3 JS) and the detection of membrane bound glycoproteins over time confirm productive infections with both viruses. Therefore, TLAs mimic aspects of the human respiratory epithelium and provide a unique capability to study the interactions of respiratory viruses and their primary target tissue independent of the host's immune system.

  20. The efficacy of cetuximab in a tissue-engineered three-dimensional in vitro model of colorectal cancer

    Directory of Open Access Journals (Sweden)

    Tarig Magdeldin

    2014-07-01

    Full Text Available The preclinical development process of chemotherapeutic drugs is often carried out in two-dimensional monolayer cultures. However, a considerable amount of evidence demonstrates that two-dimensional cell culture does not accurately reflect the three-dimensional in vivo tumour microenvironment, specifically with regard to gene expression profiles, oxygen and nutrient gradients and pharmacokinetics. With this objective in mind, we have developed and established a physiologically relevant three-dimensional in vitro model of colorectal cancer based on the removal of interstitial fluid from collagen type I hydrogels. We employed the RAFT™ (Real Architecture For 3D Tissue system for producing three-dimensional cultures to create a controlled reproducible, multiwell testing platform. Using the HT29 and HCT116 cell lines to model epidermal growth factor receptor expressing colorectal cancers, we characterized three-dimensional cell growth and morphology in addition to the anti-proliferative effects of the anti–epidermal growth factor receptor chemotherapeutic agent cetuximab in comparison to two-dimensional monolayer cultures. Cells proliferated well for 14 days in three-dimensional culture and formed well-defined cellular aggregates within the concentrated collagen matrix. Epidermal growth factor receptor expression levels revealed a twofold and threefold increase in three-dimensional cultures for both HT29 and HCT116 cells in comparison to two-dimensional monolayers, respectively (p < 0.05; p < 0.01. Cetuximab efficacy was significantly lower in HT29 three-dimensional cultures in comparison to two-dimensional monolayers, whereas HCT116 cells in both two-dimension and three-dimension were non-responsive to treatment in agreement with their KRAS mutant status. In summary, these results confirm the use of a three-dimensional in vitro cancer model as a suitable drug-screening platform for in vitro pharmacological testing.

  1. Anatomically Inspired Three-dimensional Micro-tissue Engineered Neural Networks for Nervous System Reconstruction, Modulation, and Modeling.

    Science.gov (United States)

    Struzyna, Laura A; Adewole, Dayo O; Gordián-Vélez, Wisberty J; Grovola, Michael R; Burrell, Justin C; Katiyar, Kritika S; Petrov, Dmitriy; Harris, James P; Cullen, D Kacy

    2017-05-31

    Functional recovery rarely occurs following injury or disease-induced degeneration within the central nervous system (CNS) due to the inhibitory environment and the limited capacity for neurogenesis. We are developing a strategy to simultaneously address neuronal and axonal pathway loss within the damaged CNS. This manuscript presents the fabrication protocol for micro-tissue engineered neural networks (micro-TENNs), implantable constructs consisting of neurons and aligned axonal tracts spanning the extracellular matrix (ECM) lumen of a preformed hydrogel cylinder hundreds of microns in diameter that may extend centimeters in length. Neuronal aggregates are delimited to the extremes of the three-dimensional encasement and are spanned by axonal projections. Micro-TENNs are uniquely poised as a strategy for CNS reconstruction, emulating aspects of brain connectome cytoarchitecture and potentially providing means for network replacement. The neuronal aggregates may synapse with host tissue to form new functional relays to restore and/or modulate missing or damaged circuitry. These constructs may also act as pro-regenerative "living scaffolds" capable of exploiting developmental mechanisms for cell migration and axonal pathfinding, providing synergistic structural and soluble cues based on the state of regeneration. Micro-TENNs are fabricated by pouring liquid hydrogel into a cylindrical mold containing a longitudinally centered needle. Once the hydrogel has gelled, the needle is removed, leaving a hollow micro-column. An ECM solution is added to the lumen to provide an environment suitable for neuronal adhesion and axonal outgrowth. Dissociated neurons are mechanically aggregated for precise seeding within one or both ends of the micro-column. This methodology reliably produces self-contained miniature constructs with long-projecting axonal tracts that may recapitulate features of brain neuroanatomy. Synaptic immunolabeling and genetically encoded calcium

  2. Three-dimensional topography of the gingival line of young adult maxillary teeth: curve averaging using reverse-engineering methods.

    Science.gov (United States)

    Park, Young-Seok; Chang, Mi-Sook; Lee, Seung-Pyo

    2011-01-01

    This study attempted to establish three-dimensional average curves of the gingival line of maxillary teeth using reconstructed virtual models to utilize as guides for dental implant restorations. Virtual models from 100 full-mouth dental stone cast sets were prepared with a three-dimensional scanner and special reconstruction software. Marginal gingival lines were defined by transforming the boundary points to the NURBS (nonuniform rational B-spline) curve. Using an iterative closest point algorithm, the sample models were aligned and the gingival curves were isolated. Each curve was tessellated by 200 points using a uniform interval. The 200 tessellated points of each sample model were averaged according to the index of each model. In a pilot experiment, regression and fitting analysis of one obtained average curve was performed to depict it as mathematical formulae. The three-dimensional average curves of six maxillary anterior teeth, two maxillary right premolars, and a maxillary right first molar were obtained, and their dimensions were measured. Average curves of the gingival lines of young people were investigated. It is proposed that dentists apply these data to implant platforms or abutment designs to achieve ideal esthetics. The curves obtained in the present study may be incorporated as a basis for implant component design to improve the biologic nature and related esthetics of restorations.

  3. Construction of bionic tissue engineering cartilage scaffold based on three-dimensional printing and oriented frozen technology.

    Science.gov (United States)

    Xu, Yuanyuan; Guo, Xiao; Yang, Shuaitao; Li, Long; Zhang, Peng; Sun, Wei; Liu, Changyong; Mi, Shengli

    2018-02-20

    Articular cartilage (AC) has gradient features in both mechanics and histology as well as a poor regeneration ability. The repair of AC poses difficulties in both research and the clinic. In this paper, a gradient scaffold based on poly(lactic-co-glycolic acid) (PLGA)-extracellular matrix was proposed. Cartilage scaffolds with a three-layer gradient structure were fabricated by PLGA through three-dimensional printing, and the microstructure orientation and pore fabrication were made by decellularized extracellular matrix injection and directional freezing. The manufactured scaffold has a mechanical strength close to that of real cartilage. A quantitative optimization of the Young's modulus and shear modulus was achieved by material mechanics formulas, which achieved a more accurate mechanical bionic and a more stable interface performance because of the one-time molding process. At the same time, the scaffolds have a bionic and gradient microstructure orientation and pore size, and the stratification ratio can be quantitatively optimized by design of the freeze box and temperature simulation. In general, this paper provides a method to optimize AC scaffolds by both mechanics and histology as well as a bionic multimaterial scaffold. This paper is of significance for cell culture and clinical transplantation experiments. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2018. © 2018 Wiley Periodicals, Inc.

  4. An engineering method for interactive inviscid-boundary layers in three-dimensional hypersonic flows. Ph.D. Thesis - North Carolina State Univ., Raleigh

    Science.gov (United States)

    Riley, Christopher J.

    1992-01-01

    An engineering method has been developed that couples an approximate three dimensional inviscid technique with the axisymmetric analog and a set of approximate convective heating equations. The displacement effect on the boundary layer on the outer inviscid flow is calculated and included as a boundary condition in the inviscid technique. This accounts for the viscous interaction present at lower Reynolds numbers. The method is applied to blunted axisymmetric and three dimensional elliptic cones at angle of attack for the laminar hypersonic flow of a perfect gas. The method is applied to turbulent and equilibrium-air conditions. The present technique predicts surface heating rates, pressures, and shock shapes that compare favorably with experimental (ground-test and flight) data and numerical solutions of the Navier-Stokes and viscous shock-layer equations. In addition, the inclusion of viscous interaction significantly improves results obtained at lower Reynolds numbers. The new technique represents a major improvement over current engineering aerothermal methods with only a modest increase in computational effort.

  5. Three-dimensional structural engineering of nanoporous alumina by controlled sprinkling of an electrolyte on a porous anodic alumina (PAA) template

    Science.gov (United States)

    Moradi, M.; Noormohammadi, M.; Behzadi, F.

    2011-02-01

    The significant effect of anodization current on the morphology of nanopores encourages us to consider a novel method for engineering these nanostructures. In this paper we study a controlled anodization process using controlled electrolyte stirring. This is done using an electrical pump with variable speed for sprinkling an electrolyte on a membrane. The variable voltage applied to the pump can control the temperature gradient and diffusion of the ions which produce the anodization current. Here we show the significant role of pumping and how this effect can be used in the engineering of nanopores as a three-dimensional nanostructure. These experiments are carried out for a variety of anodization voltages and various electrolyte concentrations, and thus we investigate how these parameters in the vicinity of pumping can control the porosity of the template in three dimensions.

  6. Three-dimensional neuroimaging

    International Nuclear Information System (INIS)

    Toga, A.W.

    1990-01-01

    This book reports on new neuroimaging technologies that are revolutionizing the study of the brain be enabling investigators to visualize its structure and entire pattern of functional activity in three dimensions. The book provides a theoretical and practical explanation of the new science of creating three-dimensional computer images of the brain. The coverage includes a review of the technology and methodology of neuroimaging, the instrumentation and procedures, issues of quantification, analytic protocols, and descriptions of neuroimaging systems. Examples are given to illustrate the use of three-dimensional enuroimaging to quantitate spatial measurements, perform analysis of autoradiographic and histological studies, and study the relationship between brain structure and function

  7. Robot based three-dimensional welding for jet engine blade repair and rapid prototyping of small components

    Science.gov (United States)

    Thukaram, Santosh Kumar

    Aero engines are made up of a large number of blades which are subject to wear and damage. They are expensive and must be repaired wherever possible. Engines also have small components which are required in small numbers that need to be developed rapidly. The first part of this research work focuses on developing a robust automated blade repair method using robotic welding. Optimal weld parameters were developed for build-up of edges having different thicknesses. Samples with varying Current and varying travel speed were produced and their micro hardness values were compared. Blade profiles were welded upon. The second part involves a methodology for producing small components using rapid prototyping (RP) techniques. This part involves use of 3D robotic welding for layered manufacturing. Tensile samples produced using the metal RP method were tested and results were found to be well above the minimum cast specifications for the given material.

  8. Hierarchical mesoporous bioactive glass/alginate composite scaffolds fabricated by three-dimensional plotting for bone tissue engineering

    International Nuclear Information System (INIS)

    Luo Yongxiang; Lode, Anja; Gelinsky, Michael; Wu Chengtie

    2013-01-01

    Constructing bioactive scaffolds with controllable architecture for bone tissue engineering and drug delivery still maintains a significant challenge. In this study, we have developed a composite material consisting of mesoporous bioactive glass (MBG) and concentrated alginate pastes for fabrication of hierarchical scaffolds by 3D plotting. The scaffold structure contains well-ordered nano-channels, micropores as well as controllable macropores beneficial for bone tissue engineering applications and drug delivery. The structural architecture of the scaffolds has been optimized by efficient designing of the plotting coordination. The effects of MBG on mechanical strength, apatite mineralization, cytocompatibility and drug delivery properties of the composite scaffolds have been systematically studied. Transmission electron microscopy, scanning electron microscopy and energy-dispersive spectrometry were used to characterize composition and microstructure of the composite scaffolds. The MBG/alginate pastes showed good processability in the 3D plotting process, in which stable MBG/alginate composite scaffolds with controllable architecture can be prepared. The incorporation of MBG particles significantly improved the mechanical properties and apatite-mineralization ability of alginate scaffolds as well as enhanced the attachment and alkaline phosphatase activity of human bone marrow-derived mesenchymal stem cells cultivated onto the scaffolds. Dexamethasone, used as a model drug, can be efficiently loaded in MBG particles and then incorporated into alginate scaffolds resulting in a more sustained release as a function of the MBG content. Our results have indicated that 3D-plotted MBG incorporated alginate scaffolds with well-ordered nano-pores, controllable large pores, and significantly improved physicochemical, biological and drug-delivery properties could be a platform for bone tissue engineering. (paper)

  9. Collagen-alginate as bioink for three-dimensional (3D) cell printing based cartilage tissue engineering.

    Science.gov (United States)

    Yang, Xingchen; Lu, Zhenhui; Wu, Huayu; Li, Wei; Zheng, Li; Zhao, Jinmin

    2018-02-01

    Articular cartilage repair is still a huge challenge for researchers and clinicians. 3D bioprinting could be an innovative technology for cartilage tissue engineering. In this study, we used collagen type I (COL) or agarose (AG) mixed with sodium alginate (SA) to serve as 3D bioprinting bioinks and incorporated chondrocytes to construct in vitro 3D printed cartilage tissue. Swelling ratio, mechanical properties, scanning electron microscopy (SEM), cell viability and cytoskeleton, biochemistry analysis and quantitative real-time polymerase chain reaction (qRT-PCR) were performed to investigate the function of different bioinks in 3D printing cartilage tissue engineering applications. The results showed that the mechanical strength was improved in both SA/COL and SA/AG groups compared to SA alone. Besides, the addition of COL or AG has little impact on gelling behavior, demonstrating the advantage as bioinks for 3D printing. Among the three scaffolds, SA/COL could distinctly facilitated cell adhesion, accelerated cell proliferation and enhanced the expression of cartilage specific genes such as Acan, Col2al and Sox9 than the other two groups. Lower expression of Col1a1, the fibrocartilage marker, was present in SA/COL group than that in both of SA and SA/AG groups. The results indicated that SA/COL effectively suppressed dedifferentiation of chondrocytes and preserved the phenotype. In summary, 3D bioprinted SA/COL with favorable mechanical strength and biological functionality is promising in cartilage tissue engineering. Copyright © 2017. Published by Elsevier B.V.

  10. Electrochemical evidence for asialoglycoprotein receptor – mediated hepatocyte adhesion and proliferation in three dimensional tissue engineering scaffolds

    Energy Technology Data Exchange (ETDEWEB)

    Vasanthan, Kirthanashri S.; Sethuraman, Swaminathan; Parthasarathy, Meera, E-mail: meera_p@scbt.sastra.edu

    2015-08-26

    Asialoglycoprotein receptor (ASGPR) is one of the recognition motifs on the surface of hepatocytes, which promote their adhesion to extracellular matrix in liver tissue and appropriate artificial surfaces. ASGPR-mediated adhesion is expected to minimize trans-differentiation of hepatocytes in vitro that is generally observed in integrin-mediated adhesion. The aim of the present study is to verify the role of ASGPR in hepatocyte adhesion and proliferation in scaffolds for hepatic tissue engineering. Scanning Electrochemical Microscopy (SECM) is emerging as a suitable non-invasive analytical tool due to its high sensitivity and capability to correlate the morphology and activity of live cells. HepG2 cells and rat primary hepatocytes cultured in Polyvinyl alcohol (PVA)/Gelatin hydrogel scaffolds with and without galactose (a ligand for ASGPR) modification are studied using SECM. Systematic investigation of live cells cultured for different durations in scaffolds of different compositions (9:1 and 8:2 PVA:Gelatin with and without galactose) reveals significant improvement in cell–cell communication and proliferation on galactose incorporated scaffolds, thereby demonstrating the positive influence of ASGPR-mediated adhesion. In this work, we have also developed a methodology to quantify the respiratory activity and intracellular redox activity of live cells cultured in porous tissue engineering scaffolds. Using this methodology, SECM results are compared with routine cell culture assays viz., MTS ((1-Oxyl-2,2,5,5,-tetramethyl-Δ3-pyrroline-3-methyl) Methanethiosulfonate) and Albumin assays to demonstrate the better sensitivity of SECM. In addition, the present study demonstrates SECM as a reliable and sensitive tool to monitor the activity of live cells cultured in scaffolds for tissue engineering, which could be used on a routine basis. - Highlights: • A methodology for electrochemical imaging of polymer scaffolds is proposed. • The new methodology allows

  11. Three-dimensional study of grain boundary engineering effects on intergranular stress corrosion cracking of 316 stainless steel in high temperature water

    Science.gov (United States)

    Liu, Tingguang; Xia, Shuang; Bai, Qin; Zhou, Bangxin; Zhang, Lefu; Lu, Yonghao; Shoji, Tetsuo

    2018-01-01

    The intergranular cracks and grain boundary (GB) network of a GB-engineered 316 stainless steel after stress corrosion cracking (SCC) test in high temperature high pressure water of reactor environment were investigated by two-dimensional and three-dimensional (3D) characterization in order to expose the mechanism that GB-engineering mitigates intergranular SCC. The 3D microstructure shown that the essential characteristic of the GB-engineered microstructure is formation of many large twin-boundaries as a result of multiple-twinning, which results in the formation of large grain-clusters. The large grain-clusters played a key role to the improvement of intergranular SCC resistance by GB-engineering. The main intergranular cracks propagated in a zigzag along the outer boundaries of these large grain-clusters because all inner boundaries of the grain-clusters were twin-boundaries (∑3) or twin-related boundaries (∑3n) which had much lower susceptibility to SCC than random boundaries. These large grain-clusters had tree-ring-shaped topology structure and very complex morphology. They got tangled so that difficult to be separated during SCC, resulting in some large crack-bridges retained in the crack surface.

  12. Magnetic resonance imaging tracking of human adipose derived stromal cells within three-dimensional scaffolds for bone tissue engineering

    Directory of Open Access Journals (Sweden)

    C Lalande

    2011-04-01

    Full Text Available For bone tissue engineering, human Adipose Derived Stem Cells (hADSCs are proposed to be associated with a scaffold for promoting bone regeneration. After implantation, cellularised scaffolds require a non-invasive method for monitoring their fate in vivo. The purpose of this study was to use Magnetic Resonance Imaging (MRI-based tracking of these cells, labelled with magnetic agents for in vivo longitudinal assessment. hADSCs were isolated from adipose tissue and labelled with USPIO-rhodamine (Ultrasmall SuperParamagnetic Iron Oxide. USPIO internalisation, absence of toxicity towards hADSCs, and osteogenic differentiation of the labelled cells were evaluated in standard culture conditions. Labelled cells were then seeded within a 3D porous polysaccharide-based scaffold and imaged in vitro using fluorescence microscopy and MRI. Cellularised scaffolds were implanted subcutaneously in nude mice and MRI analyses were performed from 1 to 28 d after implantation. In vitro, no effect of USPIO labelling on cell viability and osteogenic differentiation was found. USPIO were efficiently internalised by hADSCs and generated a high T2* contrast. In vivo MRI revealed that hADSCs remain detectable until 28 d after implantation and could migrate from the scaffold and colonise the area around it. These data suggested that this scaffold might behave as a cell carrier capable of both holding a cell fraction and delivering cells to the site of implantation. In addition, the present findings evidenced that MRI is a reliable technique to validate cell-seeding procedures in 3D porous scaffolds, and to assess the fate of hADSCs transplanted in vivo.

  13. Three-Dimensional Human Cardiac Tissue Engineered by Centrifugation of Stacked Cell Sheets and Cross-Sectional Observation of Its Synchronous Beatings by Optical Coherence Tomography.

    Science.gov (United States)

    Haraguchi, Yuji; Hasegawa, Akiyuki; Matsuura, Katsuhisa; Kobayashi, Mari; Iwana, Shin-Ichi; Kabetani, Yasuhiro; Shimizu, Tatsuya

    2017-01-01

    Three-dimensional (3D) tissues are engineered by stacking cell sheets, and these tissues have been applied in clinical regenerative therapies. The optimal fabrication technique of 3D human tissues and the real-time observation system for these tissues are important in tissue engineering, regenerative medicine, cardiac physiology, and the safety testing of candidate chemicals. In this study, for aiming the clinical application, 3D human cardiac tissues were rapidly fabricated by human induced pluripotent stem (iPS) cell-derived cardiac cell sheets with centrifugation, and the structures and beatings in the cardiac tissues were observed cross-sectionally and noninvasively by two optical coherence tomography (OCT) systems. The fabrication time was reduced to approximately one-quarter by centrifugation. The cross-sectional observation showed that multilayered cardiac cell sheets adhered tightly just after centrifugation. Additionally, the cross-sectional transmissions of beatings within multilayered human cardiac tissues were clearly detected by OCT. The observation showed the synchronous beatings of the thicker 3D human cardiac tissues, which were fabricated rapidly by cell sheet technology and centrifugation. The rapid tissue-fabrication technique and OCT technology will show a powerful potential in cardiac tissue engineering, regenerative medicine, and drug discovery research.

  14. 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

  15. Three-dimensional metamaterials

    Science.gov (United States)

    Burckel, David Bruce [Albuquerque, NM

    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.

  16. 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

  17. Microlaser-based three-dimensional display

    Science.gov (United States)

    Takeuchi, Eric B.; Bergstedt, Robert; Hargis, David E.; Higley, Paul D.

    1999-08-01

    Three dimensional (3D) displays are critical for viewing complex multi-dimensional information and for viewing representations of the three dimensional real world. A teaming arrangement between Laser Power Corporation (LPC) and Specialty Devices, Inc. (SDI) has led to the feasibility demonstration of a directly-viewed three dimensional volumetric display. LPC has developed red, green, and blue (RGB) diode pumped solid state microlaser display technology for use as a high resolution, high brightness display engine for the three dimensional display. Concurrently, SDI has developed a unique technology for viewing high resolution three dimensional volumetric images without external viewing aids (eye wear). When coupled to LPC's display engine, the resultant all solid state three dimensional display presets a true, physical three dimensionality which is directly viewable from all angles by multiple viewers without additional viewing equipment (eye wear). The resultant volumetric display will further enable applications such as the 'virtual sandbox,' visualization of radar and sonar data, air traffic control, remote surgery and diagnostics, and CAD workstations.

  18. Numerical Simulation of Mass Transfer and Three-Dimensional Fabrication of Tissue-Engineered Cartilages Based on Chitosan/Gelatin Hybrid Hydrogel Scaffold in a Rotating Bioreactor.

    Science.gov (United States)

    Zhu, Yanxia; Song, Kedong; Jiang, Siyu; Chen, Jinglian; Tang, Lingzhi; Li, Siyuan; Fan, Jiangli; Wang, Yiwei; Zhao, Jiaquan; Liu, Tianqing

    2017-01-01

    Cartilage tissue engineering is believed to provide effective cartilage repair post-injuries or diseases. Biomedical materials play a key role in achieving successful culture and fabrication of cartilage. The physical properties of a chitosan/gelatin hybrid hydrogel scaffold make it an ideal cartilage biomimetic material. In this study, a chitosan/gelatin hybrid hydrogel was chosen to fabricate a tissue-engineered cartilage in vitro by inoculating human adipose-derived stem cells (ADSCs) at both dynamic and traditional static culture conditions. A bioreactor that provides a dynamic culture condition has received greater applications in tissue engineering due to its optimal mass transfer efficiency and its ability to simulate an equivalent physical environment compared to human body. In this study, prior to cell-scaffold fabrication experiment, mathematical simulations were confirmed with a mass transfer of glucose and TGF-β2 both in rotating wall vessel bioreactor (RWVB) and static culture conditions in early stage of culture via computational fluid dynamic (CFD) method. To further investigate the feasibility of the mass transfer efficiency of the bioreactor, this RWVB was adopted to fabricate three-dimensional cell-hydrogel cartilage constructs in a dynamic environment. The results showed that the mass transfer efficiency of RWVB was faster in achieving a final equilibrium compared to culture in static culture conditions. ADSCs culturing in RWVB expanded three times more compared to that in static condition over 10 days. Induced cell cultivation in a dynamic RWVB showed extensive expression of extracellular matrix, while the cell distribution was found much more uniformly distributing with full infiltration of extracellular matrix inside the porous scaffold. The increased mass transfer efficiency of glucose and TGF-β2 from RWVB promoted cellular proliferation and chondrogenic differentiation of ADSCs inside chitosan/gelatin hybrid hydrogel scaffolds. The

  19. A three-dimensional multiporous fibrous scaffold fabricated with regenerated spider silk protein/poly(l-lactic acid) for tissue engineering.

    Science.gov (United States)

    Yu, Qiaozhen; Sun, Chengjun

    2015-02-01

    An axially aligned three-dimensional (3-D) fibrous scaffold was fabricated with regenerated spider silk protein (RSSP)/poly (l-lactic acid) (PLLA) through electrospinning and post treatment. The morphology, mechanical and degradation properties of the scaffold were controlled through the weight ratio of RSSP to PLLA, the thickness of the scaffold and the treatment time. The scaffold with a weight ratio of 2:3 (RSSP:PLLA) had a nanoleaves-on-nanofibers hierarchical nanostructure; the length and thickness of the nanoleaves were about 400 and 30 nm, respectively. The holes of the scaffolds ranged from hundreds of nanometers to several microns. The scaffold showed an ideal mechanical property that it was stiff when dry, but became soft once hydrated in the culture medium. Its degradation rate was very slow in the first 2 months, and then accelerated in the following 2 months. The pH values of the degradation mediums of all the samples remained in the range of 7.40-7.12 during degradation for 6 months. It had good biocompatibility with PC 12 cells. The aligned hierarchical nanostructure could guide the directions of the axon extension. This scaffold has a potential application in Tissue Engineering and controlled release. This study provides a method to produce synthetic or natural biodegradable polymer scaffold with tailored morphology, mechanical, and degradation properties. © 2014 Wiley Periodicals, Inc.

  20. Three dimensional energy profile:

    International Nuclear Information System (INIS)

    Kowsari, Reza; Zerriffi, Hisham

    2011-01-01

    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.

  1. Three-dimensional echocardiography

    International Nuclear Information System (INIS)

    Buck, Thomas

    2011-01-01

    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.

  2. Three-Dimensional Engineered High Fidelity Normal Human Lung Tissue-Like Assemblies (TLA) as Targets for Human Respiratory Virus Infections

    Science.gov (United States)

    Goodwin, T. J.; Deatly, A. M.; Suderman, M. T.; Lin, Y.-H.; Chen, W.; Gupta, C. K.; Randolph, V. B.; Udem, S. A.

    2003-01-01

    Unlike traditional two-dimensional (2D) cell cultures, three-dimensional (3D) tissue-like assemblies (TLA) (Goodwin et aI, 1992, 1993, 2000 and Nickerson et aI. , 2001,2002) offer high organ fidelity with the potential to emulate the infective dynamics of viruses and bacteria in vivo. Thus, utilizing NASA micro gravity Rotating Wall Vessel (RWV) technology, in vitro human broncho-epithelial (HBE) TLAs were engineered to mimic in vivo tissue for study of human respiratory viruses. These 3D HBE TLAs were propagated from a human broncho-tracheal cell line with a mesenchymal component (HBTC) as the foundation matrix and either an adult human broncho-epithelial cell (BEAS-2B) or human neonatal epithelial cell (16HBE140-) as the overlying element. Resulting TLAs share several characteristic features with in vivo human respiratory epithelium including tight junctions, desmosomes and cilia (SEM, TEM). The presence of epithelium and specific lung epithelium markers furthers the contention that these HBE cells differentiate into TLAs paralleling in vivo tissues. A time course of infection of these 3D HBE TLAs with human respiratory syncytial virus (hRSV) wild type A2 strain, indicates that virus replication and virus budding are supported and manifested by increasing virus titer and detection of membrane-bound F and G glycoproteins. Infected 3D HBE TLAs remain intact for up to 12 days compared to infected 2D cultures that are destroyed in 2-3 days. Infected cells show an increased vacuolation and cellular destruction (by transmission electron microscopy) by day 9; whereas, uninfected cells remain robust and morphologically intact. Therefore, the 3D HBE TLAs mimic aspects of human respiratory epithelium providing a unique opportunity to analyze, for the first time, simulated in vivo viral infection independent of host immune response.

  3. Biocompatible Silk Noil-Based Three-Dimensional Carded-Needled Nonwoven Scaffolds Guide the Engineering of Novel Skin Connective Tissue.

    Science.gov (United States)

    Chiarini, Anna; Freddi, Giuliano; Liu, Daisong; Armato, Ubaldo; Dal Prà, Ilaria

    2016-08-01

    Retracting hypertrophic scars resulting from healed burn wounds heavily impact on the patients' life quality. Biomaterial scaffolds guiding burned-out skin regeneration could suppress or lessen scar retraction. Here we report a novel silk noil-based three-dimensional (3D) nonwoven scaffold produced by carding and needling with no formic acid exposure, which might improve burn healing. Once wetted, it displays human skin-like physical features and a high biocompatibility. Human keratinocyte-like cervical carcinoma C4-I cells seeded onto the carded-needled nonwovens in vitro quickly adhered to them, grew, and actively metabolized glutamine releasing lactate. As on plastic, they released no proinflammatory IL-1β, although secreting tumor necrosis factor-alpha, an inducer of the autocrine mitogen amphiregulin in such cells. Once grafted into interscapular subcutaneous tissue of mice, carded-needled nonwovens guided the afresh assembly of a connective tissue enveloping the fibroin microfibers and filling the interposed voids within 3 months. Fibroblasts and a few poly- or mononucleated macrophages populated the engineered tissue. Besides, its extracellular matrix contained thin sparse collagen fibrils and a newly formed vascular network whose endothelin-1-expressing endothelial cells grew first on the fibroin microfibrils and later expanded into the intervening matrix. Remarkably, no infiltrates of inflammatory leukocytes and no packed collagen fibers bundles among fibroin microfibers, no fibrous capsules at the grafts periphery, and hence no foreign body response was obtained at the end of 3 months of observation. Therefore, we posit that silk noil-based 3D carded-needled nonwoven scaffolds are tools for translational medicine studies as they could guide connective tissue regeneration at deep burn wounds averting scar retraction with good functional results.

  4. Optical projection tomography can be used to investigate spatial distribution of chondrocytes in three-dimensional biomaterial scaffolds for cartilage tissue engineering.

    Science.gov (United States)

    Järvinen, Elina; Muhonen, Virpi; Haaparanta, Anne-Marie; Kellomäki, Minna; Kiviranta, Ilkka

    2014-01-01

    Biomaterial scaffolds have been used in autologous chondrocyte implantation to facilitate the repair of large lesions and to advance the formation of articular cartilage [Exp. Biol. Med. (Maywood) 237(1) (2012), 10-17]. Biomaterial scaffolds are usually three-dimensional (3-D) porous structures consisting of biodegradable materials to support articular cartilage formation. Adequate porosity of the scaffold is necessary for uniform cell distribution and cell attachment, and the density of the cells in the scaffold should be appropriate for cartilage formation [Cartilage 3(2) (2012), 108-117]. There have been only a restricted number of studies on the spatial distribution of cells in scaffolds, and on the role of this to cartilage formation [J. Biotechnol. 129 (2007), 516-531; Biotechnol. Progr. 14 (1998), 193-202; Biotechnol. Bioeng. 84 (2003), 205-214]. This may be due to the limited availability of appropriate visualization methods. Acquiring 3-D images throughout the scaffold by histology or confocal methods are not applicable to all types of scaffolds, and moreover, they are time consuming, laborious and thus not very feasible for a large scale analysis. To make the visualization of the spatial distribution of the cells easier in biomaterial scaffolds we have applied optical projection tomography (OPT). OPT microscope produces high-resolution 3-D images of both fluorescent and non-fluorescent specimens [Science 296(5567) (2002), 541-545]. Here we demonstrate that the OPT method can be used for the evaluation and visualization of the cell seeding method, spatial distribution and density of cells in biomaterial scaffolds and thus establish the OPT as a valid tool for analysis of cell distribution in cartilage tissue engineering samples.

  5. Three-dimensional ICT reconstruction

    International Nuclear Information System (INIS)

    Zhang Aidong; Li Ju; Chen Fa; Sun Lingxia

    2005-01-01

    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)

  6. Three-dimensional ICT reconstruction

    International Nuclear Information System (INIS)

    Zhang Aidong; Li Ju; Chen Fa; Sun Lingxia

    2004-01-01

    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 order, 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)

  7. Three dimensional moire pattern alignment

    Science.gov (United States)

    Juday, Richard D. (Inventor)

    1991-01-01

    An apparatus is disclosed for determining three dimensional positioning relative to a predetermined point utilizing moire interference patterns such that the patterns are complementary when viewed on axis from the predetermined distance. Further, the invention includes means for determining rotational positioning in addition to three dimensional translational positioning.

  8. The Three-Dimensional Sign.

    Science.gov (United States)

    Davis, Daniel R.

    1997-01-01

    Discusses the implications of the three-dimensional sign proposed by Harris (1990) for general linguistic theory and the philosophy of language. The article places the principal characteristics of the three-dimensional sign (contextuality, cotemporality, communicational relevance, and experiential grounding) against those of the two-dimensional…

  9. Three dimensional magnetic abacus memory.

    Science.gov (United States)

    Zhang, ShiLei; Zhang, JingYan; Baker, Alexander A; Wang, ShouGuo; Yu, GuangHua; Hesjedal, Thorsten

    2014-08-22

    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.

  10. Three dimensional magnetic abacus memory

    Science.gov (United States)

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

    2015-03-01

    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 individual 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 which envisages a classical abacus with the beads operated by electron spins. It is inspired by the idea of second quantization, dealing with the memory state of the entire stack simultaneously. Direct read operations are implemented by measuring the artificially engineered `quantized' Hall voltage, representing a count of the spin-up and spin-down layers in the stack. This concept of `second quantization of memory' realizes the 3D memory architecture with superior reading and operation efficiency, thus is a promising approach for future nonvolatile magnetic random access memory.

  11. 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...

  12. Formation of three-dimensional cell/polymer constructs for bone tissue engineering in a spinner flask and a rotating wall vessel bioreactor

    Science.gov (United States)

    Sikavitsas, Vassilios I.; Bancroft, Gregory N.; Mikos, Antonios G.; McIntire, L. V. (Principal Investigator)

    2002-01-01

    The aim of this study is to investigate the effect of the cell culture conditions of three-dimensional polymer scaffolds seeded with rat marrow stromal cells (MSCs) cultured in different bioreactors concerning the ability of these cells to proliferate, differentiate towards the osteoblastic lineage, and generate mineralized extracellular matrix. MSCs harvested from male Sprague-Dawley rats were culture expanded, seeded on three-dimensional porous 75:25 poly(D,L-lactic-co-glycolic acid) biodegradable scaffolds, and cultured for 21 days under static conditions or in two model bioreactors (a spinner flask and a rotating wall vessel) that enhance mixing of the media and provide better nutrient transport to the seeded cells. The spinner flask culture demonstrated a 60% enhanced proliferation at the end of the first week when compared to static culture. On day 14, all cell/polymer constructs exhibited their maximum alkaline phosphatase activity (AP). Cell/polymer constructs cultured in the spinner flask had 2.4 times higher AP activity than constructs cultured under static conditions on day 14. The total osteocalcin (OC) secretion in the spinner flask culture was 3.5 times higher than the static culture, with a peak OC secretion occurring on day 18. No considerable AP activity and OC secretion were detected in the rotating wall vessel culture throughout the 21-day culture period. The spinner flask culture had the highest calcium content at day 14. On day 21, the calcium deposition in the spinner flask culture was 6.6 times higher than the static cultured constructs and over 30 times higher than the rotating wall vessel culture. Histological sections showed concentration of cells and mineralization at the exterior of the foams at day 21. This phenomenon may arise from the potential existence of nutrient concentration gradients at the interior of the scaffolds. The better mixing provided in the spinner flask, external to the outer surface of the scaffolds, may explain the

  13. Three-dimensional analysis of internal flow characteristics in the injection nozzle tip of direct-injection diesel engines; Sanjigen suchi kaiseki ni yoru DI diesel kikan no nenryo funsha nozzle nai ryudo tokusei no kaimei

    Energy Technology Data Exchange (ETDEWEB)

    Ogawa, H.; Matsui, Y.; Kimura, S. [Nissan Motor Co. Ltd. Tokyo (Japan)

    1997-10-01

    To reduce the exhaust emissions and fuel consumption of direct-injection diesel engines, it is essential to optimize the fuel injection equipment closely related to combustion and emission characteristics. In this study, three-dimensional computation has been applied to investigate the effects of the injection nozzle specifications (e.g., sac volume, round shape at the inlet of the nozzle hole) and needle tip deviation on internal flow characteristics. The computational results revealed that the effects of the nozzle specifications and needle tip deviation with a smaller needle lift on internal flow characteristics and a general approach to optimize the injection nozzle specifications were obtained. 3 refs., 10 figs., 1 tab.

  14. Bioprinting of a mechanically enhanced three-dimensional dual cell-laden construct for osteochondral tissue engineering using a multi-head tissue/organ building system

    International Nuclear Information System (INIS)

    Shim, Jin-Hyung; Lee, Jung-Seob; Cho, Dong-Woo; Kim, Jong Young

    2012-01-01

    The aim of this study was to build a mechanically enhanced three-dimensional (3D) bioprinted construct containing two different cell types for osteochondral tissue regeneration. Recently, the production of 3D cell-laden structures using various scaffold-free cell printing technologies has opened up new possibilities. However, ideal 3D complex tissues or organs have not yet been printed because gel-state hydrogels have been used as the principal material and are unable to maintain the desired 3D structure due to their poor mechanical strength. In this study, thermoplastic biomaterial polycaprolactone (PCL), which shows relatively high mechanical properties as compared with hydrogel, was used as a framework for enhancing the mechanical stability of the bioprinted construct. Two different alginate solutions were then infused into the previously prepared framework consisting of PCL to create the 3D construct for osteochondral printing. For this work, a multi-head tissue/organ building system (MtoBS), which was particularly designed to dispense thermoplastic biomaterial and hydrogel having completely different rheology properties, was newly developed and used to bioprint osteochondral tissue. It was confirmed that the line width, position and volume control of PCL and alginate solutions were adjustable in the MtoBS. Most importantly, dual cell-laden 3D constructs consisting of osteoblasts and chondrocytes were successfully fabricated. Further, the separately dispensed osteoblasts and chondrocytes not only retained their initial position and viability, but also proliferated up to 7 days after being dispensed. (paper)

  15. Equilibrium: three-dimensional configurations

    International Nuclear Information System (INIS)

    Anon.

    1987-01-01

    This chapter considers toroidal MHD configurations that are inherently three-dimensional. The motivation for investigation such complicated equilibria is that they possess the potential for providing toroidal confinement without the need of a net toroidal current. This leads to a number of advantages with respect to fusion power generation. First, the attractive feature of steady-state operation becomes more feasible since such configurations no longer require a toroidal current transformer. Second, with zero net current, one potentially dangerous class of MHD instabilities, the current-driven kink modes, is eliminated. Finally, three-dimensional configurations possess nondegenerate flux surfaces even in the absence of plasma pressure and plasma current. Although there is an enormous range of possible three-dimensional equilibria, the configurations of interest are accurately described as axisymmetric tori with superimposed helical fields; furthermore, they possess no net toroidal current. Instead, two different and less obvious restoring forces are developed: the helical sideband force and the toroidal dipole current force. Each is discussed in detail in Chapter 7. A detailed discussion of the parallel current constraint, including its physical significance, is given in section 7.2. A general analysis of helical sideband equilibria, along with a detailed description of the Elmo bumpy torus, is presented in sections 7.3 and 7.4. A general description of toroidal dipole-current equilibria, including a detailed discussion of stellarators, heliotrons, and torsatrons, is given in sections 7.5 and 7.6

  16. Methods of Monitoring Cell Fate and Tissue Growth in Three-Dimensional Scaffold-Based Strategies for In Vitro Tissue Engineering.

    Science.gov (United States)

    Leferink, Anne M; van Blitterswijk, Clemens A; Moroni, Lorenzo

    2016-08-01

    In the field of tissue engineering, there is a need for methods that allow assessing the performance of tissue-engineered constructs noninvasively in vitro and in vivo. To date, histological analysis is the golden standard to retrieve information on tissue growth, cellular distribution, and cell fate on tissue-engineered constructs after in vitro cell culture or on explanted specimens after in vivo applications. Yet, many advances have been made to optimize imaging techniques for monitoring tissue-engineered constructs with a sub-mm or μm resolution. Many imaging modalities have first been developed for clinical applications, in which a high penetration depth has been often more important than lateral resolution. In this study, we have reviewed the current state of the art in several imaging approaches that have shown to be promising in monitoring cell fate and tissue growth upon in vitro culture. Depending on the aimed tissue type and scaffold properties, some imaging methods are more applicable than others. Optical methods are mostly suited for transparent materials such as hydrogels, whereas magnetic resonance-based methods are mostly applied to obtain contrast between hard and soft tissues regardless of their transparency. Overall, this review shows that the field of imaging in scaffold-based tissue engineering is developing at a fast pace and has the potential to overcome the limitations of destructive endpoint analysis.

  17. Emergency housing systems from three-dimensional engineered fiberboard : temporary building systems for lightweight, portable, easy-to-assemble, reusable, recyclable, and biodegradable structures

    Science.gov (United States)

    Jerrold E. Winandy; John F. Hunt; Christopher Turk; James R. Anderson

    2006-01-01

    Following natural disasters (such as hurricanes, tornados, or tsunamis), when civilians become displaced, or when military troops are deployed overseas, temporary housing is often a critical need. The USDA Forest Products Laboratory recently developed a lightweight, transportable, reusable, and recyclable biocomposite building material—threedimensional engineered...

  18. Real three-dimensional biquadrics

    Energy Technology Data Exchange (ETDEWEB)

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

    2010-09-07

    We find the topological types of biquadrics (complete intersections of two real four-dimensional quadrics). The rigid isotopy classes of real three-dimensional biquadrics were described long ago: there are nine such classes. We find the correspondence between the topological types of real biquadrics and their rigid isotopy classes, and show that only two rigid isotopy classes have the same topological type. One of these classes consists of real GM-varieties and the other contains no GM-varieties. We also study the sets of real lines on real biquadrics.

  19. Three-dimensional dynamic fabrication of engineered cartilage based on chitosan/gelatin hybrid hydrogel scaffold in a spinner flask with a special designed steel frame

    Energy Technology Data Exchange (ETDEWEB)

    Song, Kedong, E-mail: kedongsong@dlut.edu.cn [State Key Laboratory of Fine Chemicals, Dalian R& D Center for Stem Cell and Tissue Engineering, Dalian University of Technology, Dalian 116024 (China); Li, Liying; Li, Wenfang [State Key Laboratory of Fine Chemicals, Dalian R& D Center for Stem Cell and Tissue Engineering, Dalian University of Technology, Dalian 116024 (China); Zhu, Yanxia [Anti-Ageing and Regenerative Medicine Centre, Shenzhen University, 3688 Nanhai Avenue, Shenzhen 518060 Guangdong (China); Jiao, Zeren [State Key Laboratory of Fine Chemicals, Dalian R& D Center for Stem Cell and Tissue Engineering, Dalian University of Technology, Dalian 116024 (China); Lim, Mayasari [Division of Bioengineering, School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore 637457 (Singapore); Fang, Meiyun [Department of Hematology, First Affiliated Hospital, Dalian Medical University, Dalian 116011 (China); Shi, Fangxin [Department of Oncology, First Affiliated Hospital of Dalian Medical University, Dalian 116011 (China); Wang, Ling, E-mail: whwl@hotmail.com [Department of Obstetrics and Gynecology, First Affiliated Hospital, Dalian Medical University, Dalian 116011 (China); Liu, Tianqing, E-mail: liutq@dlut.edu.cn [State Key Laboratory of Fine Chemicals, Dalian R& D Center for Stem Cell and Tissue Engineering, Dalian University of Technology, Dalian 116024 (China)

    2015-10-01

    Cartilage transplantation using in vitro tissue engineered cartilage is considered a promising treatment for articular cartilage defects. In this study, we assessed the advantages of adipose derived stem cells (ADSCs) combined with chitosan/gelatin hybrid hydrogel scaffolds, which acted as a cartilage biomimetic scaffold, to fabricate a tissue engineered cartilage dynamically in vitro and compared this with traditional static culture. Physical properties of the hydrogel scaffolds were evaluated and ADSCs were inoculated into the hydrogel at a density of 1 × 10{sup 7} cells/mL and cultured in a spinner flask with a special designed steel framework and feed with chondrogenic inductive media for two weeks. The results showed that the average pore size, porosity, swelling rate and elasticity modulus of hybrid scaffolds with good biocompatibility were 118.25 ± 19.51 μm, 82.60 ± 2.34%, 361.28 ± 0.47% and 61.2 ± 0.16 kPa, respectively. ADSCs grew well in chitosan/gelatin hybrid scaffold and successfully differentiated into chondrocytes, showing that the scaffolds were suitable for tissue engineering applications in cartilage regeneration. Induced cells cultivated in a dynamic spinner flask with a special designed steel frame expressed more proteoglycans and the cell distribution was much more uniform with the scaffold being filled mostly with extracellular matrix produced by cells. A spinner flask with framework promoted proliferation and chondrogenic differentiation of ADSCs within chitosan/gelatin hybrid scaffolds and accelerated dynamic fabrication of cell–hydrogel constructs, which could be a selective and good method to construct tissue engineered cartilage in vitro. - Highlights: • ADSCs/hybrid scaffold constructs are dynamically fabricated in a spinner flask with a special framework. • Inside convection in spinner flask made enough supplement of oxygen and nutrients far beyond the depth of passive diffusion. • 3D culture environment accelerated mass

  20. 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.

  1. A study of a three-dimensional PLGA sponge containing natural polymers co-cultured with endothelial and mesenchymal stem cells as a tissue engineering scaffold.

    Science.gov (United States)

    Shim, Jung Bo; Ankeny, Randall F; Kim, Hyeongseok; Nerem, Robert M; Khang, Gilson

    2014-08-01

    The interaction between vascular endothelial cells (ECs) and vascular smooth muscle cells (VSMCs) in a complex hemodynamic and mechanical environment plays an important role in the control of blood vessel growth and function. Despite the importance of VSMCs, substitutes are needed for vascular therapies. A potential VSMC substitute is human adult bone marrow derived mesenchymal stem cells (hMSCs). In this study, the effect of poly(lactic-co-glycolic acid) (PLGA) scaffolds containing three natural polymers (demineralized bone particles, silk, and small intestine submucosa) on the phenotype of MSCs and SMCs cultured with or without ECs was investigated. The study objective was to create a media equivalent for a tissue engineered blood vessel using PLGA, natural polymers, and MSCs co-cultured with ECs. The PLGA containing the natural polymers silk and SIS showed increased proliferation and cell adhesion. The presence of silk and DBP promoted a MSC phenotype change into a SMC-like phenotype at the mRNA level; however these differences at the protein level were not seen. Additionally, PLGA containing SIS did not induce SMC gene or protein upregulation. Finally, the effect of ECs in combination with the natural polymers was tested. When co-cultured with ECs, the mRNA of SMC specific markers in MSCs and SMCs were increased when compared to SMCs or MSCs alone. However, MSCs, when co-cultured with ECs on PLGA containing silk, exhibited significantly increased α-SMA and calponin expression when compared to PLGA only scaffolds. These results indicate that the natural polymer silk in combination with the co-culture of endothelial cells was most effective at increasing cell viability and inducing a SMC-like phenotype at the mRNA and protein level in MSCs.

  2. Differentiation of mesenchymal stem cells for cartilage tissue engineering: Individual and synergetic effects of three-dimensional environment and mechanical loading.

    Science.gov (United States)

    Panadero, J A; Lanceros-Mendez, S; Ribelles, J L Gomez

    2016-03-01

    . The authors propose broader studies implementing new high-throughput techniques for mechanical characterization of tissue engineering constructs and the inclusion of fatigue analysis as support methodology to more exhaustive mechanical characterization. Copyright © 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  3. Numerical simulation of fluid field and in vitro three-dimensional fabrication of tissue-engineered bones in a rotating bioreactor and in vivo implantation for repairing segmental bone defects.

    Science.gov (United States)

    Song, Kedong; Wang, Hai; Zhang, Bowen; Lim, Mayasari; Liu, Yingchao; Liu, Tianqing

    2013-03-01

    In this paper, two-dimensional flow field simulation was conducted to determine shear stresses and velocity profiles for bone tissue engineering in a rotating wall vessel bioreactor (RWVB). In addition, in vitro three-dimensional fabrication of tissue-engineered bones was carried out in optimized bioreactor conditions, and in vivo implantation using fabricated bones was performed for segmental bone defects of Zelanian rabbits. The distribution of dynamic pressure, total pressure, shear stress, and velocity within the culture chamber was calculated for different scaffold locations. According to the simulation results, the dynamic pressure, velocity, and shear stress around the surface of cell-scaffold construction periodically changed at different locations of the RWVB, which could result in periodical stress stimulation for fabricated tissue constructs. However, overall shear stresses were relatively low, and the fluid velocities were uniform in the bioreactor. Our in vitro experiments showed that the number of cells cultured in the RWVB was five times higher than those cultured in a T-flask. The tissue-engineered bones grew very well in the RWVB. This study demonstrates that stress stimulation in an RWVB can be beneficial for cell/bio-derived bone constructs fabricated in an RWVB, with an application for repairing segmental bone defects.

  4. Novel application of a tissue-engineered collagen-based three-dimensional bio-implant in a large tendon defect model: a broad-based study with high value in translational medicine.

    Science.gov (United States)

    Meimandi-Parizi, Abdolhamid; Oryan, Ahmad; Moshiri, Ali; Silver, Ian A

    2013-08-01

    This study was designed to investigate the effectiveness of a novel tissue-engineered three-dimensional collagen implant on healing of a large tendon-defect model, in vivo. Forty rabbits were divided into two equal groups: treated and control. A 2cm full-thickness gap was created in the left Achilles tendons of all the rabbits. To maintain the gap at the desired length (2cm), a Kessler suture was anchored within the proximal and distal ends of the remaining tendon. In the treated group a collagen implant was inserted in the gap while in the control group the gap was left unfilled. At weekly intervals the animals were examined clinically and their Achilles tendons tested bioelectrically. The hematological parameters and the serum Platelet-Derived Growth Factor of the animals were analyzed at 60 days post injury (DPI) immediately prior to euthanasia. Their injured (left) and normal contralateral Achilles tendons were harvested and examined at gross morphologic level before being subjected to biomechanical testing, and biophysical and biochemical analysis. The treated animals showed superior weight-bearing and greater physical activity than their controls. New dense tendinous tissue with a transverse diameter comparable to that of intact tendons filled the defect area of the treated tendons and had entirely replaced the collagen implant, at 60 DPI. In control lesions the defect was filled with loose areolar connective tissue similar to subcutaneous fascia. Treatment significantly improved the electrical resistance, dry matter, hydroxyproline content, water uptake and water delivery characteristics, of the healing tissue, as well as maximum load, yield load, maximum stress, yield stress and modulus of elasticity of the injured treated tendons compared to those of the control tendons (P<0.05). Use of this three-dimensional collagen implant improved the healing of large tendon defects in rabbits. Copyright © 2013 Elsevier Ltd. All rights reserved.

  5. Three-Dimensional Laser Microvision

    Science.gov (United States)

    Shimotahira, Hiroshi; Iizuka, Keigo; Chu, Sun-Chun; Wah, Christopher; Costen, Furnie; Yoshikuni, Yuzo

    2001-04-01

    A three-dimensional (3-D) optical imaging system offering high resolution in all three dimensions, requiring minimum manipulation and capable of real-time operation, is presented. The system derives its capabilities from use of the superstructure grating laser source in the implementation of a laser step frequency radar for depth information acquisition. A synthetic aperture radar technique was also used to further enhance its lateral resolution as well as extend the depth of focus. High-speed operation was made possible by a dual computer system consisting of a host and a remote microcomputer supported by a dual-channel Small Computer System Interface parallel data transfer system. The system is capable of operating near real time. The 3-D display of a tunneling diode, a microwave integrated circuit, and a see-through image taken by the system operating near real time are included. The depth resolution is 40 m; lateral resolution with a synthetic aperture approach is a fraction of a micrometer and that without it is approximately 10 m.

  6. Three dimensional imaging of otoliths

    International Nuclear Information System (INIS)

    Barry, B.; Markwitz, A.; David, B.

    2008-01-01

    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)

  7. Development of three-dimensional computed tomography system using TNRF2 of JRR-3M

    Energy Technology Data Exchange (ETDEWEB)

    Murata, Yutaka; Mochiki, Koh-ichi [Musashi Inst. of Tech., Tokyo (Japan); Matsubayashi, Masahito

    1998-01-01

    A three-dimensional filtering engine, a convolution engine, and a back projection engine were developed for real-time signal processing of three-dimensional computed tomography. The performance of the system was measured and through-put of 0.5 second per one cross sectional data processing was attained. (author)

  8. Three-dimensional fractal geometry for gas permeation in microchannels

    NARCIS (Netherlands)

    Malankowska, Magdalena; Schlautmann, Stefan; Berenschot, Erwin J.W.; Tiggelaar, Roald M.; Pina, Maria Pilar; Mallada, Reyes; Tas, Niels R.; Gardeniers, Han

    2018-01-01

    The novel concept of a microfluidic chip with an integrated three-dimensional fractal geometry with nanopores, acting as a gas transport membrane, is presented. The method of engineering the 3D fractal structure is based on a combination of anisotropic etching of silicon and corner lithography. The

  9. SU-F-P-18: Development of the Technical Training System for Patient Set-Up Considering Rotational Correction in the Virtual Environment Using Three-Dimensional Computer Graphic Engine

    Energy Technology Data Exchange (ETDEWEB)

    Imura, K [Division of Quantum Radiation Science, Department of Health Science, Graduate School of Medical Science, Kyushu University, Fukuoka (Japan); Fujibuchi, T; Hirata, H [Department of Health Science, Graduate School of Medical Science, Kyushu University, Fukuoka (Japan); Kaneko, K [Innovation Center for Educational Resource, Kyushu University, Fukuoka (Japan); Hamada, E [Cancer Treatment Center, Tobata Kyoritsu Hospital, Kitakyushu (Japan)

    2016-06-15

    Purpose: Patient set-up skills in radiotherapy treatment room have a great influence on treatment effect for image guided radiotherapy. In this study, we have developed the training system for improving practical set-up skills considering rotational correction in the virtual environment away from the pressure of actual treatment room by using three-dimensional computer graphic (3DCG) engine. Methods: The treatment room for external beam radiotherapy was reproduced in the virtual environment by using 3DCG engine (Unity). The viewpoints to perform patient set-up in the virtual treatment room were arranged in both sides of the virtual operable treatment couch to assume actual performance by two clinical staffs. The position errors to mechanical isocenter considering alignment between skin marker and laser on the virtual patient model were displayed by utilizing numerical values expressed in SI units and the directions of arrow marks. The rotational errors calculated with a point on the virtual body axis as the center of each rotation axis for the virtual environment were corrected by adjusting rotational position of the body phantom wound the belt with gyroscope preparing on table in a real space. These rotational errors were evaluated by describing vector outer product operations and trigonometric functions in the script for patient set-up technique. Results: The viewpoints in the virtual environment allowed individual user to visually recognize the position discrepancy to mechanical isocenter until eliminating the positional errors of several millimeters. The rotational errors between the two points calculated with the center point could be efficiently corrected to display the minimum technique mathematically by utilizing the script. Conclusion: By utilizing the script to correct the rotational errors as well as accurate positional recognition for patient set-up technique, the training system developed for improving patient set-up skills enabled individual user to

  10. SU-F-P-18: Development of the Technical Training System for Patient Set-Up Considering Rotational Correction in the Virtual Environment Using Three-Dimensional Computer Graphic Engine

    International Nuclear Information System (INIS)

    Imura, K; Fujibuchi, T; Hirata, H; Kaneko, K; Hamada, E

    2016-01-01

    Purpose: Patient set-up skills in radiotherapy treatment room have a great influence on treatment effect for image guided radiotherapy. In this study, we have developed the training system for improving practical set-up skills considering rotational correction in the virtual environment away from the pressure of actual treatment room by using three-dimensional computer graphic (3DCG) engine. Methods: The treatment room for external beam radiotherapy was reproduced in the virtual environment by using 3DCG engine (Unity). The viewpoints to perform patient set-up in the virtual treatment room were arranged in both sides of the virtual operable treatment couch to assume actual performance by two clinical staffs. The position errors to mechanical isocenter considering alignment between skin marker and laser on the virtual patient model were displayed by utilizing numerical values expressed in SI units and the directions of arrow marks. The rotational errors calculated with a point on the virtual body axis as the center of each rotation axis for the virtual environment were corrected by adjusting rotational position of the body phantom wound the belt with gyroscope preparing on table in a real space. These rotational errors were evaluated by describing vector outer product operations and trigonometric functions in the script for patient set-up technique. Results: The viewpoints in the virtual environment allowed individual user to visually recognize the position discrepancy to mechanical isocenter until eliminating the positional errors of several millimeters. The rotational errors between the two points calculated with the center point could be efficiently corrected to display the minimum technique mathematically by utilizing the script. Conclusion: By utilizing the script to correct the rotational errors as well as accurate positional recognition for patient set-up technique, the training system developed for improving patient set-up skills enabled individual user to

  11. Elastocapillary fabrication of three-dimensional microstructures

    NARCIS (Netherlands)

    van Honschoten, J.W.; Berenschot, Johan W.; Ondarcuhu, T.; Sanders, Remco G.P.; Sundaram, J.; Elwenspoek, Michael Curt; Tas, Niels Roelof

    2010-01-01

    We describe the fabrication of three-dimensional microstructures by means of capillary forces. Using an origami-like technique, planar silicon nitride structures of various geometries are folded to produce three-dimensional objects of 50–100 m. Capillarity is a particularly effective mechanism since

  12. A plastic surgery application in evolution: three-dimensional printing.

    Science.gov (United States)

    Gerstle, Theodore L; Ibrahim, Ahmed M S; Kim, Peter S; Lee, Bernard T; Lin, Samuel J

    2014-02-01

    Three-dimensional printing represents an evolving technology still in its infancy. Currently, individuals and small business entities have the ability to manufacture physical objects from digital renderings, computer-aided design, and open source files. Design modifications and improvements in extrusion methods have made this technology much more affordable. This article explores the potential uses of three-dimensional printing in plastic surgery. A review was performed detailing the known uses of three-dimensional printing in medicine. The potential applications of three-dimensional printing in plastic surgery are discussed. Various applications for three-dimensional printing technology have emerged in medicine, including printing organs, printing body parts, bio-printing, and computer-aided tissue engineering. In plastic surgery, these tools offer various prospective applications for surgical planning, resident education, and the development of custom prosthetics. Numerous applications exist in medicine, including the printing of devices, implants, tissue replacements, and even whole organs. Plastic surgeons may likely find this technology indispensable in surgical planning, education, and prosthetic device design and development in the near future.

  13. Primary and Secondary Three Dimensional Microbatteries

    Science.gov (United States)

    Cirigliano, Nicolas

    Today's MEMS devices are limited more so by the batteries that supply their power than the fabrication methods used to build them. Thick battery electrodes are capable of providing adequate energy, but long and tortuous diffusion pathways lead to low power capabilities. On the other hand, thin film batteries can operate at significant current densities but require large surface areas to supply practical energy. This dilemma can be solved by either developing new high capacity materials or by engineering new battery designs that decouple power and energy. Three dimensional batteries redesign traditional configurations to create nonplanar interfaces between battery components. This can be done by introducing hierarchical structures into the electrode shape. Designs such as these provide a maximum surface area over which chemical reactions can occur. Furthermore, by maintaining small feature sizes, ion diffusion and electronic transport distances can remain minimal. Manipulating these properties ensures fast kinetics that are required for high power situations. Energy density is maximized by layering material in the vertical direction, thus ensuring a minimal footprint area. Three dimensional carbon electrodes are fabricated using basic MEMS techniques. A silicon mold is anisotropically etched to produce channels of a predetermined diameter. The channels are then filled using an infiltration technique with electrode slurry. Once dried, the mold is attached to a current collector and etched using a XeF2 process. Electrodes of varying feature sizes have been fabricated using this method with aspect ratios ranging from 3.5:1 to 7:1. 3D carbon electrodes are shown to obtain capacities over 8 mAh/cm2 at 0.1 mA/cm2, or nearly 700% higher than planar carbon electrodes. When assembled with a planar cathode, the battery cell produced an average discharge capacity of 40 J/cm 2 at a current density of 0.2 mA/cm2. This places the energy density values slightly less than thick

  14. Parallelization method for three dimensional MOC calculation

    International Nuclear Information System (INIS)

    Zhang Zhizhu; Li Qing; Wang Kan

    2013-01-01

    A parallelization method based on angular decomposition for the three dimensional MOC was designed. To improve the parallel efficiency, the directions were pre-grouped and the groups were assembled to minimize the communication. The improved parallelization method was applied to the three dimensional MOC code TCM. The numerical results show that the calculation results of parallelization method are agreed with serial calculation results. The parallel efficiency gets obvious increase after the communication optimized and load balance. (authors)

  15. Three-dimensional effects in fracture mechanics

    International Nuclear Information System (INIS)

    Benitez, F.G.

    1991-01-01

    An overall view of the pioneering theories and works, which enlighten the three-dimensional nature of fracture mechanics during the last years is given. the main aim is not an exhaustive reviewing but the displaying of the last developments on this scientific field in a natural way. This work attempts to envisage the limits of disregarding the three-dimensional behaviour in theories, analyses and experiments. Moreover, it tries to draw attention on the scant fervour, although increasing, this three-dimensional nature of fracture has among the scientific community. Finally, a constructive discussion is presented on the use of two-dimensional solutions in the analysis of geometries which bear a three-dimensional configuration. the static two-dimensional solutions and its applications fields are reviewed. also, the static three-dimensional solutions, wherein a comparative analysis with elastoplastic and elastostatic solutions are presented. to end up, the dynamic three-dimensional solutions are compared to the asymptotic two-dimensional ones under the practical applications point of view. (author)

  16. [The application progress of three-dimensional cell culture technology in ophthalmology].

    Science.gov (United States)

    Zhao, Yun; Zhang, Lei; Zhao, Hong

    2015-11-01

    Three-dimensional cell culture technology is a kind of technology that cultures the cells in a three-dimensional cultivation by using a kind of scaffold materials in vitro. Its advantage is that the vivo microenvironment simulating degrees of the three-dimensional culture technology is higher than that of the two-dimensional planar cell culture model, and the controllability is also higher than the animal experiment. In recent years, with the development of tissue engineering technology, a varietiy of the stent of biological materials also a fast development, which provided a favorable platform for three-dimensional cell culture technology. In ophthalmology, three-dimensional cell culture has been applied to the cornea, retina and the visual system development and other optic tumor researches. The objective of this paper is to making a review the application status of the three-dimensional cell culture technology in the basic research and clinical treatment in ophthalmology.

  17. Towards three-dimensional optical metamaterials

    Science.gov (United States)

    Tanaka, Takuo; Ishikawa, Atsushi

    2017-12-01

    Metamaterials have opened up the possibility of unprecedented and fascinating concepts and applications in optics and photonics. Examples include negative refraction, perfect lenses, cloaking, perfect absorbers, and so on. Since these metamaterials are man-made materials composed of sub-wavelength structures, their development strongly depends on the advancement of micro- and nano-fabrication technologies. In particular, the realization of three-dimensional metamaterials is one of the big challenges in this research field. In this review, we describe recent progress in the fabrication technologies for three-dimensional metamaterials, as well as proposed applications.

  18. Towards three-dimensional optical metamaterials.

    Science.gov (United States)

    Tanaka, Takuo; Ishikawa, Atsushi

    2017-01-01

    Metamaterials have opened up the possibility of unprecedented and fascinating concepts and applications in optics and photonics. Examples include negative refraction, perfect lenses, cloaking, perfect absorbers, and so on. Since these metamaterials are man-made materials composed of sub-wavelength structures, their development strongly depends on the advancement of micro- and nano-fabrication technologies. In particular, the realization of three-dimensional metamaterials is one of the big challenges in this research field. In this review, we describe recent progress in the fabrication technologies for three-dimensional metamaterials, as well as proposed applications.

  19. Development of three dimensional solid modeler

    International Nuclear Information System (INIS)

    Zahoor, R.M.A.

    1999-01-01

    The work presented in this thesis is aimed at developing a three dimensional solid modeler employing computer graphics techniques using C-Language. Primitives have been generated, by combination of plane surfaces, for various basic geometrical shapes including cylinder, cube and cone. Back face removal technique for hidden surface removal has also been incorporated. Various transformation techniques such as scaling, translation, and rotation have been included for the object animation. Three dimensional solid modeler has been created by the union of two primitives to demonstrate the capabilities of the developed program. (author)

  20. Three-dimensional imaging utilizing energy discrimination

    International Nuclear Information System (INIS)

    Gunter, D.L.; Hoffman, K.R.; Beck, R.N.

    1990-01-01

    An algorithm is proposed for three-dimensional image reconstruction in nuclear medicine which uses scattered radiation rather than multiple projected images to determine the source depth within the body. Images taken from numerous energy windows are combined to construct the source distribution in the body. The gamma-ray camera is not moved during the imaging process. Experiments with both Tc-99m and Ga-67 demonstrate that two channels of depth information can be extracted from the low energy images produced by scattered radiation. By combining this technique with standard SPECT reconstruction using multiple projections the authors anticipate much improved spatial resolution in the overall three-dimensional reconstruction

  1. Imaging unsteady three-dimensional transport phenomena

    Indian Academy of Sciences (India)

    2014-01-05

    Jan 5, 2014 ... 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 ...

  2. Three-Dimensional Printing Surgical Applications.

    Science.gov (United States)

    AlAli, Ahmad B; Griffin, Michelle F; Butler, Peter E

    2015-01-01

    Three-dimensional printing, a technology used for decades in the industrial field, gains a lot of attention in the medical field for its potential benefits. With advancement of desktop printers, this technology is accessible and a lot of research is going on in the medical field. To evaluate its application in surgical field, which may include but not limited to surgical planning, surgical education, implants, and prosthesis, which are the focus of this review. Research was conducted by searching PubMed, Web of science, and other reliable sources. We included original articles and excluded articles based on animals, those more than 10 years old, and those not in English. These articles were evaluated, and relevant studies were included in this review. Three-dimensional printing shows a potential benefit in surgical application. Printed implants were used in patient in a few cases and show successful results; however, longer follow-up and more trials are needed. Surgical and medical education is believed to be more efficient with this technology than the current practice. Printed surgical instrument and surgical planning are also believed to improve with three-dimensional printing. Three-dimensional printing can be a very powerful tool in the near future, which can aid the medical field that is facing a lot of challenges and obstacles. However, despite the reported results, further research on larger samples and analytical measurements should be conducted to ensure this technology's impact on the practice.

  3. Imaging unsteady three-dimensional transport phenomena

    Indian Academy of Sciences (India)

    2014-01-05

    Jan 5, 2014 ... 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. Keywords. Optical measurement; fluid flow and transport; refractive index ...

  4. Three-dimensional chiral photonic superlattices.

    Science.gov (United States)

    Thiel, M; Fischer, H; von Freymann, G; Wegener, M

    2010-01-15

    We investigate three-dimensional photonic superlattices composed of polymeric helices in various spatial checkerboard-like arrangements. Depending on the relative phase shift and handedness of the chiral building blocks, different circular-dichroism resonances appear or are suppressed. Samples corresponding to four different configurations are fabricated by direct laser writing. The measured optical transmittance spectra are in good agreement with numerical calculations.

  5. 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...

  6. Electron crystallography of three dimensional protein crystals

    NARCIS (Netherlands)

    Georgieva, Dilyana

    2008-01-01

    This thesis describes an investigation of the potential of electron diffraction for studying three dimensional sub-micro-crystals of proteins and pharmaceuticals. A prerequisite for using electron diffraction for structural studies is the predictable availability of tiny crystals. A method for

  7. Three-dimensional temporal reconstruction and analysis of plume images

    Science.gov (United States)

    Dhawan, Atam P.; Disimile, Peter J.; Peck, Charles, III

    1992-01-01

    An experiment with two subsonic jets generating a cross-flow was conducted as part of a study of the structural features of temporal reconstruction of plume images. The flow field structure was made visible using a direct injection flow visualization technique. It is shown that image analysis and temporal three-dimensional visualization can provide new information on the vortical structural dynamics of multiple jets in a cross-flow. It is expected that future developments in image analysis, quantification and interpretation, and flow visualization of rocket engine plume images may provide a tool for correlating the engine diagnostic features by interpreting the evolution of the structures in the plume.

  8. Three-dimensional integrated CAE system applying computer graphic technique

    International Nuclear Information System (INIS)

    Kato, Toshisada; Tanaka, Kazuo; Akitomo, Norio; Obata, Tokayasu.

    1991-01-01

    A three-dimensional CAE system for nuclear power plant design is presented. This system utilizes high-speed computer graphic techniques for the plant design review, and an integrated engineering database for handling the large amount of nuclear power plant engineering data in a unified data format. Applying this system makes it possible to construct a nuclear power plant using only computer data from the basic design phase to the manufacturing phase, and it increases the productivity and reliability of the nuclear power plants. (author)

  9. Three-dimensional patterning methods and related devices

    Energy Technology Data Exchange (ETDEWEB)

    Putnam, Morgan C.; Kelzenberg, Michael D.; Atwater, Harry A.; Boettcher, Shannon W.; Lewis, Nathan S.; Spurgeon, Joshua M.; Turner-Evans, Daniel B.; Warren, Emily L.

    2016-12-27

    Three-dimensional patterning methods of a three-dimensional microstructure, such as a semiconductor wire array, are described, in conjunction with etching and/or deposition steps to pattern the three-dimensional microstructure.

  10. Three-Dimensional Elasto-Plastic Calculations Using Yield Surfaces with Corner Discontinuities

    DEFF Research Database (Denmark)

    Clausen, Johan; Andersen, Lars; Damkilde, Lars

    2009-01-01

    This paper presents a simple and efficient way of dealing with the corners found in many yield surfaces, especially in geotechnical engineering. The efficiency of the method is demonstrated through three-dimensional computational examples.......This paper presents a simple and efficient way of dealing with the corners found in many yield surfaces, especially in geotechnical engineering. The efficiency of the method is demonstrated through three-dimensional computational examples....

  11. Three-dimensional imaging modalities in endodontics

    International Nuclear Information System (INIS)

    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 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

  12. Arching in three-dimensional clogging

    Directory of Open Access Journals (Sweden)

    Török János

    2017-01-01

    Full Text Available Arching in dry granular material is a long established concept, however it remains still an open question how three-dimensional orifices clog. We investigate by means of numerical simulations and experimental data how the outflow creates a blocked configuration of particles. We define the concave surface of the clogged dome by two independent methods (geometric and density based. The average shape of the cupola for spheres is almost a hemisphere but individual samples have large holes in the structure indicating a blocked state composed of two-dimensional force chains rather than three-dimensional objects. The force chain structure justifies this assumption. For long particles the clogged configurations display large variations, and in certain cases the empty region reaches a height of 5 hole diameters. These structures involve vertical walls consisting of horizontally placed stable stacking of particles.

  13. Three dimensional digital imaging of environmental data

    International Nuclear Information System (INIS)

    Nichols, R.L.; Eddy, C.A.

    1991-01-01

    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

  14. Arching in three-dimensional clogging

    Science.gov (United States)

    Török, János; Lévay, Sára; Szabó, Balázs; Somfai, Ellák; Wegner, Sandra; Stannarius, Ralf; Börzsönyi, Tamás

    2017-06-01

    Arching in dry granular material is a long established concept, however it remains still an open question how three-dimensional orifices clog. We investigate by means of numerical simulations and experimental data how the outflow creates a blocked configuration of particles. We define the concave surface of the clogged dome by two independent methods (geometric and density based). The average shape of the cupola for spheres is almost a hemisphere but individual samples have large holes in the structure indicating a blocked state composed of two-dimensional force chains rather than three-dimensional objects. The force chain structure justifies this assumption. For long particles the clogged configurations display large variations, and in certain cases the empty region reaches a height of 5 hole diameters. These structures involve vertical walls consisting of horizontally placed stable stacking of particles.

  15. Three dimensional contact/impact methodology

    International Nuclear Information System (INIS)

    Kulak, R.F.

    1987-01-01

    The simulation of three-dimensional interface mechanics between reactor components and structures during static contact or dynamic impact is necessary to realistically evaluate their structural integrity to off-normal loads. In our studies of postulated core energy release events, we have found that significant structure-structure interactions occur in some reactor vessel head closure designs and that fluid-structure interactions occur within the reactor vessel. Other examples in which three-dimensional interface mechanics play an important role are: (1) impact response of shipping casks containing spent fuel, (2) whipping pipe impact on reinforced concrete panels or pipe-to-pipe impact after a pipe break, (3) aircraft crash on secondary containment structures, (4) missiles generated by turbine failures or tornados, and (5) drops of heavy components due to lifting accidents. The above is a partial list of reactor safety problems that require adequate treatment of interface mechanics and are discussed in this paper

  16. THREE DIMENSIONAL GRAPHICAL REPRESENTATION OF QUALITY

    Directory of Open Access Journals (Sweden)

    Vineet V. Kumar

    2014-03-01

    Full Text Available Quality is an important aspect for every firm in modern era of competition. Every product has tough competition in terms of market reach. The factor, which actually makes any product long run in market, is quality and hence quality is the stepping-stone for success of any firm. For everyone meaning of quality is different. We have seen several economists who have defined quality by considering different factors, but what all of them have common in them is Customer satisfaction. Customer satisfaction is the ultimate result of quality. In three-dimensional graphical representation of quality, optimum quality is obtained by using three-dimensional graph by considering some important factors governing quality of any product, limiting factor, and customer satisfaction.

  17. 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.

  18. Three-dimensional imaging modalities in endodontics

    Science.gov (United States)

    Mao, Teresa

    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 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. PMID:25279337

  19. Geometric actions for three-dimensional gravity

    Science.gov (United States)

    Barnich, G.; González, H. A.; Salgado-Rebolledo, P.

    2018-01-01

    The solution space of three-dimensional asymptotically anti-de Sitter or flat Einstein gravity is given by the coadjoint representation of two copies of the Virasoro group in the former and the centrally extended BMS3 group in the latter case. Dynamical actions that control these solution spaces are usually constructed by starting from the Chern–Simons formulation and imposing all boundary conditions. In this note, an alternative route is followed. We study in detail how to derive these actions from a group-theoretical viewpoint by constructing geometric actions for each of the coadjoint orbits, including the appropriate Hamiltonians. We briefly sketch relevant generalizations and potential applications beyond three-dimensional gravity.

  20. SNAP - a three dimensional neutron diffusion code

    International Nuclear Information System (INIS)

    McCallien, C.W.J.

    1993-02-01

    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)

  1. Analysis of three-dimensional transonic compressors

    Science.gov (United States)

    Bourgeade, A.

    1984-01-01

    A method for computing the three-dimensional transonic flow around the blades of a compressor or of a propeller is given. The method is based on the use of the velocity potential, on the hypothesis that the flow is inviscid, irrotational and isentropic. The equation of the potential is solved in a transformed space such that the surface of the blade is mapped into a plane where the periodicity is implicit. This equation is in a nonconservative form and is solved with the help of a finite difference method using artificial time. A computer code is provided and some sample results are given in order to demonstrate the influence of three-dimensional effects and the blade's rotation.

  2. Three-dimensional display of document set

    Science.gov (United States)

    Lantrip, David B [Oxnard, CA; Pennock, Kelly A [Richland, WA; Pottier, Marc C [Richland, WA; Schur, Anne [Richland, WA; Thomas, James J [Richland, WA; Wise, James A [Richland, WA; York, Jeremy [Bothell, WA

    2009-06-30

    A method for spatializing text content for enhanced visual browsing and analysis. The invention is applied to large text document corpora such as digital libraries, regulations and procedures, archived reports, and the like. The text content from these sources may be transformed to a spatial representation that preserves informational characteristics from the documents. The three-dimensional representation may then be visually browsed and analyzed in ways that avoid language processing and that reduce the analysts' effort.

  3. Three-dimensional simulation of vortex breakdown

    Science.gov (United States)

    Kuruvila, G.; Salas, M. D.

    1990-01-01

    The integral form of the complete, unsteady, compressible, three-dimensional Navier-Stokes equations in the conservation form, cast in generalized coordinate system, are solved, numerically, to simulate the vortex breakdown phenomenon. The inviscid fluxes are discretized using Roe's upwind-biased flux-difference splitting scheme and the viscous fluxes are discretized using central differencing. Time integration is performed using a backward Euler ADI (alternating direction implicit) scheme. A full approximation multigrid is used to accelerate the convergence to steady state.

  4. Three-Dimensional Dynamic Loading of Sand

    Science.gov (United States)

    2011-02-01

    oading conditions exist at the bulk scale, and exam ples include planetary impact and crater formation, tectonic plate movement , ballistic im pact and...found further way from an impact event, where the bulk material does not necessarily experience uniform loading in excess of the Hugoniot elastic li...either as a collection of quartz spheres in a three-dimensional rectilinear dom ain for t he mesoscale simulations or as a single representative material

  5. 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 sapph...... as verified through electromagnetic simulations and parameter retrieval. Our approach extends dynamic metamaterial tuning to magnetic control, and may find applications in switching and modulation, polarization control, or tunable perfect absorbers....

  6. Three-Dimensional Ocean Noise Modeling

    Science.gov (United States)

    2015-03-01

    realistic and complex three-dimensional bathymetry. This is achieved by using a parabolic equation [PE) propagation model and the reciprocity principle...explain the horizontal noise directionality observed in the Tonga Trench [Barclay, 2014], which was found not to be a 3D effect, but rather due to...modeled noise arriving on the axis of the canyon has significantly perturbed zero-crossings when compared to the equivalent Nx2D result. Theoretical

  7. Three-dimensional accelerating electromagnetic waves.

    Science.gov (United States)

    Bandres, Miguel A; Alonso, Miguel A; Kaminer, Ido; Segev, Mordechai

    2013-06-17

    We present a general theory of three-dimensional non-paraxial spatially-accelerating waves of the Maxwell equations. These waves constitute a two-dimensional structure exhibiting shape-invariant propagation along semicircular trajectories. We provide classification and characterization of possible shapes of such beams, expressed through the angular spectra of parabolic, oblate and prolate spheroidal fields. Our results facilitate the design of accelerating beams with novel structures, broadening scope and potential applications of accelerating beams.

  8. Three-Dimensional Reconstruction of Sandpile Interiors

    Science.gov (United States)

    Seidler, G. T.

    2001-03-01

    The granular bed, or sandpile, has become one of the condensed matter physicist's favorite systems. In addition to conceptual appeal, the simplest sandpile of monodisperse hard spheres is a valuable model system for understanding powders, liquids, and metallic glasses. Any fundamental approach to the transport and mechanical properties of three-dimensional mesoscale disordered materials must follow from a thorough understanding of their structure. However, in the overwhelming majority of cases, structure measurements have been limited to the mean filling fraction and the structural autocorrelation function. This is particularly unfortunate in the ongoing sandpile renaissance, where some of the most interesting questions concern structure and the relationship between structure and dynamics. I will discuss the combination of synchrotron x-ray microtomography and computer vision algorithms to perform three-dimensional virtual reconstructions of real sandpiles. This technique is rapid and noninvasive, and is applicable to samples large enough to separate bulk and boundary properties. The resulting complete knowledge of structure can be used to calculate otherwise inaccessible correlation functions. I will present results for several measures of the bond-orientational order in three-dimensional sandpiles, including fabric tensors and nematic order parameters.

  9. Multiparallel Three-Dimensional Optical Microscopy

    Science.gov (United States)

    Nguyen, Lam K.; Price, Jeffrey H.; Kellner, Albert L.; Bravo-Zanoquera, Miguel

    2010-01-01

    Multiparallel three-dimensional optical microscopy is a method of forming an approximate three-dimensional image of a microscope sample as a collection of images from different depths through the sample. The imaging apparatus includes a single microscope plus an assembly of beam splitters and mirrors that divide the output of the microscope into multiple channels. An imaging array of photodetectors in each channel is located at a different distance along the optical path from the microscope, corresponding to a focal plane at a different depth within the sample. The optical path leading to each photodetector array also includes lenses to compensate for the variation of magnification with distance so that the images ultimately formed on all the photodetector arrays are of the same magnification. The use of optical components common to multiple channels in a simple geometry makes it possible to obtain high light-transmission efficiency with an optically and mechanically simple assembly. In addition, because images can be read out simultaneously from all the photodetector arrays, the apparatus can support three-dimensional imaging at a high scanning rate.

  10. 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.

  11. 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.

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

    International Nuclear Information System (INIS)

    Ono, Ichiro; Ohura, Takehiko; Kimura, Chu

    1989-01-01

    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.)

  13. 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.).

  14. Photogrammetry: applications of a three-dimensional remote measurement technique

    International Nuclear Information System (INIS)

    Peak, K.

    1988-01-01

    Photogrammetry is defined as the precise art of abstracting measurements from photographic images. Used for many years as a means to produce the world's maps, it has, in recent years, been applied in many engineering environments. The nuclear industry has, in particular, benefitted from the close range applications of photogrammetry. This paper sets out to describe the techniques involved, from the site photography through to the analytical data extraction. It will include a number of examples of where photogrammetry has been used in the nuclear industry as a remote measurement technique, from simple monitoring exercises to the compilation of complex three-dimensional as-built computer models. (author)

  15. Evaluation of solar energy over three dimensional objects

    International Nuclear Information System (INIS)

    Serposhan, S.; Yaghoubi, M.

    2002-01-01

    The knowledge of solar irradiation is important in heating and cooling of buildings architectural engineering, various solar energy utilizations, and for any system design exposed to sun radiation. In the present article, simulation is made to predict solar irradiation over any three-dimensional objects. Special consideration is made to evaluate solar radiation intensity distribution over semi-circular roof and domed roofs. For practical applications, hourly and average daily solar radiation distribution for a series of three Heller type huge cooling towers of Fars Power Plant is also determined

  16. Single-camera, three-dimensional particle tracking velocimetry

    OpenAIRE

    Peterson, K.; Regaard, B.; Heinemann, S.; Sick, V.

    2012-01-01

    This paper introduces single-camera, three-dimensional particle tracking velocimetry (SC3D-PTV), an image-based, single-camera technique for measuring 3-component, volumetric velocity fields in environments with limited optical access, in particular, optically accessible internal combustion engines. The optical components used for SC3D-PTV are similar to those used for two-camera stereoscopic-PIV, but are adapted to project two simultaneous images onto a single image sensor. A novel PTV algor...

  17. CATIA Core Tools Computer Aided Three-Dimensional Interactive Application

    CERN Document Server

    Michaud, Michel

    2012-01-01

    CATIA Core Tools: Computer-Aided Three-Dimensional Interactive Application explains how to use the essential features of this cutting-edge solution for product design and innovation. The book begins with the basics, such as launching the software, configuring the settings, and managing files. Next, you'll learn about sketching, modeling, drafting, and visualization tools and techniques. Easy-to-follow instructions along with detailed illustrations and screenshots help you get started using several CATIA workbenches right away. Reverse engineering--a valuable product development skill--is also covered in this practical resource.

  18. 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...... a 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...

  19. 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...

  20. Three-Dimensional Printing in Orthopedic Surgery.

    Science.gov (United States)

    Eltorai, Adam E M; Nguyen, Eric; Daniels, Alan H

    2015-11-01

    Three-dimensional (3D) printing is emerging as a clinically promising technology for rapid prototyping of surgically implantable products. With this commercially available technology, computed tomography or magnetic resonance images can be used to create graspable objects from 3D reconstructed images. Models can enhance patients' understanding of their pathology and surgeon preoperative planning. Customized implants and casts can be made to match an individual's anatomy. This review outlines 3D printing, its current applications in orthopedics, and promising future directions. Copyright 2015, SLACK Incorporated.

  1. Three-dimensional teletherapy treatment planning

    International Nuclear Information System (INIS)

    Panthaleon van Eck, R.B. van.

    1986-01-01

    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.)

  2. Creating three-dimensional thermal maps

    CSIR Research Space (South Africa)

    Price

    2011-11-01

    Full Text Available stream_source_info Price_2011.pdf.txt stream_content_type text/plain stream_size 30895 Content-Encoding ISO-8859-1 stream_name Price_2011.pdf.txt Content-Type text/plain; charset=ISO-8859-1 Creating Three...-Dimensional Thermal Maps Mathew Price Cogency cc Cape Town Email: mathew@cogency.co.za Jeremy Green CSIR Centre for Mining Innovation Johannesburg Email: jgreen@csir.co.za John Dickens CSIR Centre for Mining Innovation Johannesburg Email: jdickens...

  3. 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.

  4. Three-dimensional radiation treatment planning

    International Nuclear Information System (INIS)

    Mohan, R.

    1989-01-01

    A major aim of radiation therapy is to deliver sufficient dose to the tumour volume to kill the cancer cells while sparing the nearby health organs to prevent complications. With the introduction of devices such as CT and MR scanners, radiation therapy treatment planners have access to full three-dimensional anatomical information to define, simulate, and evaluate treatments. There are a limited number of prototype software systems that allow 3D treatment planning currently in use. In addition, there are more advanced tools under development or still in the planning stages. They require sophisticated graphics and computation equipment, complex physical and mathematical algorithms, and new radiation treatment machines that deliver dose very precisely under computer control. Components of these systems include programs for the identification and delineation of the anatomy and tumour, the definition of radiation beams, the calculation of dose distribution patterns, the display of dose on 2D images and as three dimensional surfaces, and the generation of computer images to verify proper patient positioning in treatment. Some of these functions can be performed more quickly and accurately if artificial intelligence or expert systems techniques are employed. 28 refs., figs

  5. Three dimensional animated images of anorectal malformations

    International Nuclear Information System (INIS)

    Ueno, Shigeru; Yanagimachi, Noriharu; Muro, Isao; Komiya, Taizo; Yokoyama, Seishichi; Hirakawa, Hitoshi; Tajima, Tomoo; Mitomi, Toshio; Suto, Yasuzo.

    1996-01-01

    Accurate reconstruction of the pelvic structures is a most important factor in obtaining a desirable result after anorectoplasty for a patient with anorectal malformation. Preoperative evaluation of the anatomy is indispensable for choosing an appropriate operative method in each case. To facilitate preoperative evaluation, three dimensional animated images of the pelvic structure of patients with anorectal malformations were constructed by computer graphics based upon tomographic images obtained from magnetic resonance imaging. Axial 1-mm thick images of the pelvic portion were generated with spoiling pulse gradient echo sequences using short repetition times (13 msec TR) and short echo times (6 msec TE) with a flip angle of 25 degrees with the patient in the jack-knife position. Graphic data from MR images were transferred to a graphic work station and processed on it. The skin surface, the ano-rectum, the lower urinary tract and the sphincter musculature were segmented by thresholding images by the signal intensity. Three dimensional images were displayed by surface rendering method using the segmented data of each organ and then animation images of these organs were obtained. The anatomy of each type of anomaly was easily recognized by 3-D visualization, and animation of the pelvic viscera and the sphincter musculature made the images more realistic. Animated images of the musculature were especially useful for simulating surgical procedures and could be helpful for reviewing surgical results. (author)

  6. The Three-Dimensional Universe with Gaia

    Science.gov (United States)

    Turon, C.; O'Flaherty, K. S.; Perryman, M. A. C.

    2005-01-01

    "The Three-Dimensional Universe with Gaia" symposium was hosted by the Observatoire de Paris (Meudon), France, from 4 to 7 October 2004. The date chosen for this symposium corresponded to the end of the definition phase of Gaia, a cornerstone mission of the European Space Agency. The purposes of this symposium were: (1) to present to the scientific community the design chosen for the mission, the final characteristics and performances, and to update the resulting scientific case; (2) to bring to the attention of the scientific community the extraordinary potential of Gaia and to share with the younger generation of scientists the expertise acquired during the preparation phases of the Gaia mission, and during all phases of the Hipparcos mission; (3) to organise the next phase of scientific preparation of the mission, in particular the data reduction which constitutes a major challenge with a petabyte of interconnected data which has to be treated in a global and iterative manner, and to prepare for the scientific exploitation of the data. The symposium was open to scientists working on the preparation of Gaia and to the large community interested in using the data from the mission. The proceedings of the symposium are published by the European Space Agency as ESA SP-576: "The Three-Dimensional Universe with Gaia". These proceedings contain invited and contributed papers for six sessions covering technical and scientific aspects of the mission.

  7. Three-dimensional electrical impedance tomography

    Science.gov (United States)

    Metherall, P.; Barber, D. C.; Smallwood, R. H.; Brown, B. H.

    1996-04-01

    THE electrical resistivity of mammalian tissues varies widely1-5 and is correlated with physiological function6-8. Electrical impedance tomography (EIT) can be used to probe such variations in vivo, and offers a non-invasive means of imaging the internal conductivity distribution of the human body9-11. But the computational complexity of EIT has severe practical limitations, and previous work has been restricted to considering image reconstruction as an essentially two-dimensional problem10,12. This simplification can limit significantly the imaging capabilities of EIT, as the electric currents used to determine the conductivity variations will not in general be confined to a two-dimensional plane13. A few studies have attempted three-dimensional EIT image reconstruction14,15, but have not yet succeeded in generating images of a quality suitable for clinical applications. Here we report the development of a three-dimensional EIT system with greatly improved imaging capabilities, which combines our 64-electrode data-collection apparatus16 with customized matrix inversion techniques. Our results demonstrate the practical potential of EIT for clinical applications, such as lung or brain imaging and diagnostic screening8.

  8. Three-dimensional turbopump flowfield analysis

    Science.gov (United States)

    Sharma, O. P.; Belford, K. A.; Ni, R. H.

    1992-01-01

    A program was conducted to develop a flow prediction method applicable to rocket turbopumps. The complex nature of a flowfield in turbopumps is described and examples of flowfields are discussed to illustrate that physics based models and analytical calculation procedures based on computational fluid dynamics (CFD) are needed to develop reliable design procedures for turbopumps. A CFD code developed at NASA ARC was used as the base code. The turbulence model and boundary conditions in the base code were modified, respectively, to: (1) compute transitional flows and account for extra rates of strain, e.g., rotation; and (2) compute surface heat transfer coefficients and allow computation through multistage turbomachines. Benchmark quality data from two and three-dimensional cascades were used to verify the code. The predictive capabilities of the present CFD code were demonstrated by computing the flow through a radial impeller and a multistage axial flow turbine. Results of the program indicate that the present code operated in a two-dimensional mode is a cost effective alternative to full three-dimensional calculations, and that it permits realistic predictions of unsteady loadings and losses for multistage machines.

  9. Exact solutions in three-dimensional gravity

    CERN Document Server

    Garcia-Diaz, Alberto A

    2017-01-01

    A self-contained text, systematically presenting the determination and classification of exact solutions in three-dimensional Einstein gravity. This book explores the theoretical framework and general physical and geometrical characteristics of each class of solutions, and includes information on the researchers responsible for their discovery. Beginning with the physical character of the solutions, these are identified and ordered on the basis of their geometrical invariant properties, symmetries, and algebraic classifications, or from the standpoint of their physical nature, for example electrodynamic fields, fluid, scalar field, or dilaton. Consequently, this text serves as a thorough catalogue on 2+1 exact solutions to the Einstein equations coupled to matter and fields, and on vacuum solutions of topologically massive gravity with a cosmological constant. The solutions are also examined from different perspectives, enabling a conceptual bridge between exact solutions of three- and four-dimensional gravit...

  10. AAOGlimpse: Three-dimensional Data Viewer

    Science.gov (United States)

    Shortridge, Keith

    2011-10-01

    AAOGlimpse is an experimental display program that uses OpenGL to display FITS data (and even JPEG images) as 3D surfaces that can be rotated and viewed from different angles, all in real-time. It is WCS-compliant and designed to handle three-dimensional data. Each plane in a data cube is surfaced in the same way, and the program allows the user to travel through a cube by 'peeling off' successive planes, or to look into a cube by suppressing the display of data below a given cutoff value. It can blink images and can superimpose images and contour maps from different sources using their world coordinate data. A limited socket interface allows communication with other programs.

  11. 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.

  12. Entanglement entropy in three dimensional gravity

    Energy Technology Data Exchange (ETDEWEB)

    Maxfield, Henry [Centre for Particle Theory & Department of Mathematical Sciences, Durham University,South Road, Durham DH1 3LE (United Kingdom)

    2015-04-07

    The Ryu-Takayanagi (RT) and covariant Hubeny-Rangamani-Takayanagi (HRT) proposals relate entanglement entropy in CFTs with holographic duals to the areas of minimal or extremal surfaces in the bulk geometry. We show how, in three dimensional pure gravity, the relevant regulated geodesic lengths can be obtained by writing a spacetime as a quotient of AdS{sub 3}, with the problem reduced to a simple purely algebraic calculation. We explain how this works in both Lorentzian and Euclidean formalisms, before illustrating its use to obtain novel results in a number of examples, including rotating BTZ, the ℝℙ{sup 2} geon, and several wormhole geometries. This includes spatial and temporal dependence of single-interval entanglement entropy, despite these symmetries being broken only behind an event horizon. We also discuss considerations allowing HRT to be derived from analytic continuation of Euclidean computations in certain contexts, and a related class of complexified extremal surfaces.

  13. Electron in three-dimensional momentum space

    Science.gov (United States)

    Bacchetta, Alessandro; Mantovani, Luca; Pasquini, Barbara

    2016-01-01

    We study the electron as a system composed of an electron and a photon, using lowest-order perturbation theory. We derive the leading-twist transverse-momentum-dependent distribution functions for both the electron and photon in the dressed electron, thereby offering a three-dimensional description of the dressed electron in momentum space. To obtain the distribution functions, we apply both the formalism of the light-front wave function overlap representation and the diagrammatic approach. We perform the calculations both in light-cone gauge and Feynman gauge, and we present a detailed discussion of the role of the Wilson lines to obtain gauge-independent results. We provide numerical results and plots for many of the computed distributions.

  14. Towards microscale electrohydrodynamic three-dimensional printing

    International Nuclear Information System (INIS)

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

    2016-01-01

    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. (paper)

  15. An Introduction of Three-dimensional Grammar

    Directory of Open Access Journals (Sweden)

    Fan Xiao

    2017-12-01

    Full Text Available This paper introduces some key points of Three-dimensional Grammar. As for the structure, it can be distinguished into syntactic structure, semantic structure and pragmatic structure from the perspectives of syntax, semantics and pragmatics. And the same is true with the followings, such as grammatical constituents, grammatical functions, grammatical meanings, grammatical focuses. Sentence types which is called sentence pattern, sentence model and sentence types respectively, and analysis methods. This paper proposes that grammatical researches should be done in accordance with the four principles, that is form and meaning co-verified, static and dynamic co-referenced, structure and function co-testified and description and interpretation co-promoted.

  16. Three-dimensional echocardiography in valve disease

    Directory of Open Access Journals (Sweden)

    Cesare Fiorentini

    2009-08-01

    Full Text Available This review covers the role of three-dimensional (3D echocardiography in the diagnosis of heart valve disease. Several factors have contributed to the evolution of this technique, which is currently a simple and routine method: rapid evolution in probe and computer technologies, demonstration that 3D data sets allowed more complete and accurate evaluation of cardiac structures, emerging clinical experience indicating the strong potential particularly in valve diseases, volume and function of the two ventricle measurements and several other fields. This report will review current and future applications of 3D echocardiography in mitral, aortic and tricuspid valve diseases underlying both qualitative (morphologic and quantitative advantages of this technique. (Heart International 2007; 3: 35-41

  17. Three dimensional thrust chamber life prediction

    Science.gov (United States)

    Armstrong, W. H.; Brogren, E. W.

    1976-01-01

    A study was performed to analytically determine the cyclic thermomechanical behavior and fatigue life of three configurations of a Plug Nozzle Thrust Chamber. This thrust chamber is a test model which represents the current trend in nozzle design calling for high performance coupled with weight and volume limitations as well as extended life for reusability. The study involved the use of different materials and material combinations to evaluate their application to the problem of low-cycle fatigue in the thrust chamber. The thermal and structural analyses were carried out on a three-dimensional basis. Results are presented which show plots of continuous temperature histories and temperature distributions at selected times during the operating cycle of the thrust chamber. Computed structural data show critical regions for low-cycle fatigue and the histories of strain within the regions for each operation cycle.

  18. Three-dimensional detectors for neutron imaging

    Science.gov (United States)

    Mendicino, R.; Dalla Betta, G.-F.

    2018-01-01

    Solid-state sensors fabricated with 3D technologies and coupled to different neutron converter materials have been developed by several groups as direct replacement of 3 He gas detectors, mainly for homeland security applications. Results so far achieved in terms of detection efficiency are quite good (up to ≃50%) and, combined with the intrinsic excellent position resolution of silicon sensors, could lead to high performance neutron imaging systems. In this paper, we review the state of the art in three-dimensional silicon sensors for thermal-neutron detection, addressing the most promising solutions for neutron imaging. Moreover, selected results from the developments at the University of Trento on 3D pixelated detectors having relatively low fabrication complexity and expected high neutron detection efficiency up to 30% will be reported.

  19. Method for Parametric Design of Three-Dimensional Shapes

    National Research Council Canada - National Science Library

    Dick, James L

    2006-01-01

    The present invention relates to computer-aided design of three-dimensional shapes and more particularly, relates to a system and method for parametric design of three-dimensional hydrodynamic shapes...

  20. Three-dimensional (3D) analysis of the temporomandibular joint

    DEFF Research Database (Denmark)

    Kitai, N.; Kreiborg, S.; Murakami, S.

    Symposium Orthodontics 2001: Where are We Now? Where are We Going?, three-dimensional analysis, temporomandibular joint......Symposium Orthodontics 2001: Where are We Now? Where are We Going?, three-dimensional analysis, temporomandibular joint...

  1. Tailoring thermal conductivity via three-dimensional porous alumina.

    Science.gov (United States)

    Abad, Begoña; Maiz, Jon; Ruiz-Clavijo, Alejandra; Caballero-Calero, Olga; Martin-Gonzalez, Marisol

    2016-12-09

    Three-dimensional anodic alumina templates (3D-AAO) are an astonishing framework with open highly ordered three-dimensional skeleton structures. Since these templates are architecturally different from conventional solids or porous templates, they teem with opportunities for engineering thermal properties. By establishing the mechanisms of heat transfer in these frameworks, we aim to create materials with tailored thermal properties. The effective thermal conductivity of an empty 3D-AAO membrane was measured. As the effective medium theory was not valid to extract the skeletal thermal conductivity of 3D-AAO, a simple 3D thermal conduction model was developed, based on a mixed series and parallel thermal resistor circuit, giving a skeletal thermal conductivity value of approximately 1.25 W·m -1 ·K -1 , which matches the value of the ordinary AAO membranes prepared from the same acid solution. The effect of different filler materials as well as the variation of the number of transversal nanochannels and the length of the 3D-AAO membrane in the effective thermal conductivity of the composite was studied. Finally, the thermal conductivity of two 3D-AAO membranes filled with cobalt and bismuth telluride was also measured, which was in good agreement with the thermal model predictions. Therefore, this work proved this structure as a powerful approach to tailor thermal properties.

  2. Vocal Fold Pathologies and Three-Dimensional Flow Separation Phenomena

    Science.gov (United States)

    Apostoli, Adam G.; Weiland, Kelley S.; Plesniak, Michael W.

    2013-11-01

    Polyps and nodules are two different pathologies, which are geometric abnormalities that form on the medial surface of the vocal folds, and have been shown to significantly disrupt a person's ability to communicate. Although the mechanism by which the vocal folds self-oscillate and the three-dimensional nature of the glottal jet has been studied, the effect of irregularities caused by pathologies is not fully understood. Examining the formation and evolution of vortical structures created by a geometric protuberance is important, not only for understanding the aerodynamic forces exerted by these structures on the vocal folds, but also in the treatment of the above-mentioned pathological conditions. Using a wall-mounted prolate hemispheroid with a 2:1 aspect ratio in cross flow, the present investigation considers three-dimensional flow separation induced by a model vocal fold polyp. Building on previous work using skin friction line visualization, both the velocity flow field and wall pressure measurements around the model polyp are presented and compared. Supported by the National Science Foundation, Grant No. CBET-1236351 and GW Center for Biomimetics and Bioinspired Engineering (COBRE).

  3. Three-dimensional computer aided design system for plant layout

    International Nuclear Information System (INIS)

    Yoshinaga, Toshiaki; Kiguchi, Takashi; Tokumasu, Shinji; Kumamoto, Kenjiro.

    1986-01-01

    The CAD system for three-dimensional plant layout planning, with which the layout of pipings, cable trays, air conditioning ducts and so on in nuclear power plants can be planned and designed effectively in a short period is reported. This system comprises the automatic routing system by storing the rich experience and know-how of designers in a computer as the knowledge, and deciding the layout automatically following the predetermined sequence by using these, the interactive layout system for reviewing the routing results from higher level and modifying to the optimum layout, the layout evaluation system for synthetically evaluating the layout from the viewpoint of the operability such as checkup and maintenance, and the data base system which enables these effective planning and design. In this report, the total constitution of this system and the technical features and effects of the individual subsystems are outlined. In this CAD system for three-dimensional plant layout planning, knowledge engineering, CAD/CAM, computer graphics and other latest technology were introduced, accordingly by applying this system to plant design, the design can be performed quickly, various case studies can be carried out at planning stage, and systematic and optimum layout planning becomes possible. (Kako, I.)

  4. Tailoring thermal conductivity via three-dimensional porous alumina

    Science.gov (United States)

    Abad, Begoña; Maiz, Jon; Ruiz-Clavijo, Alejandra; Caballero-Calero, Olga; Martin-Gonzalez, Marisol

    2016-01-01

    Three-dimensional anodic alumina templates (3D-AAO) are an astonishing framework with open highly ordered three-dimensional skeleton structures. Since these templates are architecturally different from conventional solids or porous templates, they teem with opportunities for engineering thermal properties. By establishing the mechanisms of heat transfer in these frameworks, we aim to create materials with tailored thermal properties. The effective thermal conductivity of an empty 3D-AAO membrane was measured. As the effective medium theory was not valid to extract the skeletal thermal conductivity of 3D-AAO, a simple 3D thermal conduction model was developed, based on a mixed series and parallel thermal resistor circuit, giving a skeletal thermal conductivity value of approximately 1.25 W·m−1·K−1, which matches the value of the ordinary AAO membranes prepared from the same acid solution. The effect of different filler materials as well as the variation of the number of transversal nanochannels and the length of the 3D-AAO membrane in the effective thermal conductivity of the composite was studied. Finally, the thermal conductivity of two 3D-AAO membranes filled with cobalt and bismuth telluride was also measured, which was in good agreement with the thermal model predictions. Therefore, this work proved this structure as a powerful approach to tailor thermal properties. PMID:27934930

  5. Study on three dimensional seismic isolation system

    International Nuclear Information System (INIS)

    Morishita, Masaki; Kitamura, Seiji

    2003-01-01

    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

  6. Three-Dimensional Computational Fluid Dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Haworth, D.C.; O' Rourke, P.J.; Ranganathan, R.

    1998-09-01

    Computational fluid dynamics (CFD) is one discipline falling under the broad heading of computer-aided engineering (CAE). CAE, together with computer-aided design (CAD) and computer-aided manufacturing (CAM), comprise a mathematical-based approach to engineering product and process design, analysis and fabrication. In this overview of CFD for the design engineer, our purposes are three-fold: (1) to define the scope of CFD and motivate its utility for engineering, (2) to provide a basic technical foundation for CFD, and (3) to convey how CFD is incorporated into engineering product and process design.

  7. Multimodal three-dimensional dynamic signature

    Directory of Open Access Journals (Sweden)

    Yury E. Kozlov

    2017-11-01

    Full Text Available Reliable authentication in mobile applications is among the most important information security challenges. Today, we can hardly imagine a person who would not own a mobile device that connects to the Internet. Mobile devices are being used to store large amounts of confidential information, ranging from personal photos to electronic banking tools. In 2009, colleagues from Rice University together with their collaborators from Motorola, proposed an authentication through in-air gestures. This and subsequent work contributing to the development of the method are reviewed in our introduction. At the moment, there exists a version of the gesture-based authentication software available for Android mobile devices. This software has not become widespread yet. One of likely reasons for that is the insufficient reliability of the method, which involves similar to its earlier analogs the use of only one device. Here we discuss the authentication based on the multimodal three-dimensional dynamic signature (MTDS performed by two independent mobile devices. The MTDS-based authentication technique is an advanced version of in-air gesture authentication. We describe the operation of a prototype of MTDS-based authentication, including the main implemented algorithms, as well as some preliminary results of testing the software. We expect that our method can be used in any mobile application, provided a number of additional improvements discussed in the conclusion are made.

  8. Three-dimensional supersonic vortex breakdown

    Science.gov (United States)

    Kandil, Osama A.; Kandil, Hamdy A.; Liu, C. H.

    1993-01-01

    Three-dimensional supersonic vortex-breakdown problems in bound and unbound domains are solved. The solutions are obtained using the time-accurate integration of the unsteady, compressible, full Navier-Stokes (NS) equations. The computational scheme is an implicit, upwind, flux-difference splitting, finite-volume scheme. Two vortex-breakdown applications are considered in the present paper. The first is for a supersonic swirling jet which is issued from a nozzle into a supersonic uniform flow at a lower Mach number than that of the swirling jet. The second is for a supersonic swirling flow in a configured circular duct. In the first application, an extensive study of the effects of grid fineness, shape and grid-point distribution on the vortex breakdown is presented. Four grids are used in this study and they show a substantial dependence of the breakdown bubble and shock wave on the grid used. In the second application, the bubble-type and helix-type vortex breakdown have been captured.

  9. Three dimensional characterization and archiving system

    International Nuclear Information System (INIS)

    Sebastian, R.L.; Clark, R.; Gallman, P.

    1996-01-01

    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 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

  10. Three dimensional characterization and archiving system

    International Nuclear Information System (INIS)

    Sebastian, R.L.; Clark, R.; Gallman, P.

    1995-01-01

    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 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 endoscopy in sinus surgery.

    Science.gov (United States)

    Singh, Ameet; Saraiya, Rupali

    2013-02-01

    Surgical endoscopy revolutionized the management of disease in nearly every surgical field, including rhinology. Endoscopy offered several advantages for the surgical management of rhinologic disease. However, it had a distinct disadvantage compared to direct vision, namely loss of binocular vision. Two-dimensional (2D) endoscopy limited depth perception, widely regarded as an important parameter for accurate and efficient movements during surgery. Three-dimensional (3D) endoscopic visualization has been actively pursued for decades by endoscopic surgeons in multiple surgical specialties. However, its clinical role has been limited due to technical limitations as well as successful adaptation by endoscopic surgeons to monocular cues offered by 2D technology. Until recently, stereoscopic technology included variations of dual channel video, dual chip-on-the-tip, and shutter mechanism, as well as various 3D displays. Over the past decade a novel 3D endoscopic technology was introduced. This technology used a lenticular array of lenses in front of a single video chip at the distal end of an endoscope to generate a stereoscopic view of the surgical field. Also known as the 'insect eye' technology since it mimics the compound eye of arthropods, this endoscope has reinvigorated the field of 3D endoscopic surgery. Recent developments in 3D endoscopy hold much promise for all surgical subspecialties, particularly endoscopic sinus and skull-base surgery.

  12. Three-dimensional laparoscopy: Principles and practice

    Directory of Open Access Journals (Sweden)

    Rakesh Y Sinha

    2017-01-01

    Full Text Available The largest challenge for laparoscopic surgeons is the eye–hand coordination within a three-dimensional (3D scene observed on a 2D display. The 2D view on flat screen laparoscopy is cerebrally intensive. The loss of binocular vision on a 2D display causes visual misperceptions, mainly loss of depth perception and adds to the surgeon's fatigue. This compromises the safety of laparoscopy. The 3D high-definition view with great depth perception and tactile feedback makes laparoscopic surgery more acceptable, safe and cost-effective. It improves surgical precision and hand–eye coordination, conventional and all straight stick instruments can be used, capital expenditure is less and recurring cost and annual maintenance cost are less. In this article, we have discussed the physics of 3D laparoscopy, principles of depth perception, and the different kinds of 3D systems available for laparoscopy. We have also discussed our experience of using 3D laparoscopy in over 2000 surgeries in the last 4 years.

  13. 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.

  14. Nanoscale three-dimensional single particle tracking.

    Science.gov (United States)

    Dupont, Aurélie; Lamb, Don C

    2011-11-01

    Single particle tracking (SPT) in biological systems is a quickly growing field. Many new technologies are being developed providing new tracking capabilities, which also lead to higher demands and expectations for SPT. Following a single biomolecule as it performs its function provides quantitative mechanistic information that cannot be obtained in classical ensemble methods. From the 3D trajectory, information is available over the diffusional behavior of the particle and precise position information can also be used to elucidate interactions of the tracked particle with its surroundings. Thus, three-dimensional (3D) SPT is a very valuable tool for investigating cellular processes. This review presents recent progress in 3D SPT, from image-based techniques toward more sophisticated feedback approaches. We focus mainly on the feedback technique known as orbital tracking. We present here a modified version of the original orbital tracking in which the intensities from two z-planes are simultaneously measured allowing a concomitant wide-field imaging. The system can track single particles with a precision down to 5 nm in the x-y plane and 7 nm in the axial direction. The capabilities of the system are demonstrated using single virus tracing to follow the infection pathway of Prototype Foamy Virus in living cells.

  15. THREE-DIMENSIONAL ULTRASOUND IN GYNECOLOGIC ONCOLOGY

    Directory of Open Access Journals (Sweden)

    Iztok Takač

    2003-12-01

    Full Text Available Background. Although three-dimensional ultrasound (3D US imaging has been used for a decade, debate continues about its potential clinical aplications in gynecology. The same is true for the field of gynecologic oncology. Also, reports regarding usfulness of 3D US in gynecologic oncology are limited. A few potentially useful clinical applications have been described and some of these are now gaining general acceptance. In this paper, the usfulness of 3D US in the main areas of its application is demonstrated: diagnostics of cervical, endometrial, ovarian and breast cancer.Conclusions. An important advantage of 3D US over conventional two-dimensional imaging is the ability to reconstruct and display any arbitrarily chosen section within the volume dataset as well as ability to measure the volume of pelvic organs regardless of their shape. 3D US also allows the realtime analysis of the acquired image data to be conducted at a later time when the patient is off the examination table.

  16. Three-Dimensional Printed Thermal Regulation Textiles.

    Science.gov (United States)

    Gao, Tingting; Yang, Zhi; Chen, Chaoji; Li, Yiju; Fu, Kun; Dai, Jiaqi; Hitz, Emily M; Xie, Hua; Liu, Boyang; Song, Jianwei; Yang, Bao; Hu, Liangbing

    2017-11-28

    Space cooling is a predominant part of energy consumption in people's daily life. Although cooling the whole building is an effective way to provide personal comfort in hot weather, it is energy-consuming and high-cost. Personal cooling technology, being able to provide personal thermal comfort by directing local heat to the thermally regulated environment, has been regarded as one of the most promising technologies for cooling energy and cost savings. Here, we demonstrate a personal thermal regulated textile using thermally conductive and highly aligned boron nitride (BN)/poly(vinyl alcohol) (PVA) composite (denoted as a-BN/PVA) fibers to improve the thermal transport properties of textiles for personal cooling. The a-BN/PVA composite fibers are fabricated through a fast and scalable three-dimensional (3D) printing method. Uniform dispersion and high alignment of BN nanosheets (BNNSs) can be achieved during the processing of fiber fabrication, leading to a combination of high mechanical strength (355 MPa) and favorable heat dispersion. Due to the improved thermal transport property imparted by the thermally conductive and highly aligned BNNSs, better cooling effect (55% improvement over the commercial cotton fiber) can be realized in the a-BN/PVA textile. The wearable a-BN/PVA textiles containing the 3D-printed a-BN/PVA fibers offer a promising selection for meeting the personal cooling requirement, which can significantly reduce the energy consumption and cost for cooling the whole building.

  17. Three-Dimensional Printed Graphene Foams.

    Science.gov (United States)

    Sha, Junwei; Li, Yilun; Villegas Salvatierra, Rodrigo; Wang, Tuo; Dong, Pei; Ji, Yongsung; Lee, Seoung-Ki; Zhang, Chenhao; Zhang, Jibo; Smith, Robert H; Ajayan, Pulickel M; Lou, Jun; Zhao, Naiqin; Tour, James M

    2017-07-25

    An automated metal powder three-dimensional (3D) printing method for in situ synthesis of free-standing 3D graphene foams (GFs) was successfully modeled by manually placing a mixture of Ni and sucrose onto a platform and then using a commercial CO 2 laser to convert the Ni/sucrose mixture into 3D GFs. The sucrose acted as the solid carbon source for graphene, and the sintered Ni metal acted as the catalyst and template for graphene growth. This simple and efficient method combines powder metallurgy templating with 3D printing techniques and enables direct in situ 3D printing of GFs with no high-temperature furnace or lengthy growth process required. The 3D printed GFs show high-porosity (∼99.3%), low-density (∼0.015g cm -3 ), high-quality, and multilayered graphene features. The GFs have an electrical conductivity of ∼8.7 S cm -1 , a remarkable storage modulus of ∼11 kPa, and a high damping capacity of ∼0.06. These excellent physical properties of 3D printed GFs indicate potential applications in fields requiring rapid design and manufacturing of 3D carbon materials, for example, energy storage devices, damping materials, and sound absorption.

  18. A method for fabricating a three-dimensional carbon structure

    DEFF Research Database (Denmark)

    2017-01-01

    A method for fabricating a three-dimensional carbon structure (4) is disclosed. A mould (1) defining a three-dimensional shape is provided, and natural protein containing fibres are packed in the mould (1) at a predetermined packing density. The packed natural protein containing fibre structure (3......) undergoes pyrolysis, either while still in the mould (1) or after having been removed from the mould (1). Thereby a three-dimensional porous and electrically conducting carbon structure (4) having a three-dimensional shape defined by the three-dimensional shape of the mould (1) and a porosity defined...

  19. Micro-Mirrors for Nanoscale Three-Dimensional Microscopy

    Science.gov (United States)

    Seale, Kevin; Janetopoulos, Chris; Wikswo, John

    2013-01-01

    A research-grade optical microscope is capable of resolving fine structures in two-dimensional images. However, three-dimensional resolution, or the ability of the microscope to distinguish between objects lying above or below the focal plane from in-focus objects, is not nearly as good as in-plane resolution. In this issue of ACS Nano, McMahon et al. report the use of mirrored pyramidal wells with a conventional microscope for rapid, 3D localization and tracking of nanoparticles. Mirrors have been used in microscopy before, but recent work with MPWs is unique because it enables the rapid determination of the x-, y-, and z-position of freely diffusing nanoparticles and cellular nanostructures with unprecedented speed and spatial accuracy. As inexpensive tools for 3D visualization, mirrored pyramidal wells may prove to be invaluable aids in nanotechnology and engineering of nanomaterials. PMID:19309167

  20. Single-camera, three-dimensional particle tracking velocimetry.

    Science.gov (United States)

    Peterson, Kevin; Regaard, Boris; Heinemann, Stefan; Sick, Volker

    2012-04-09

    This paper introduces single-camera, three-dimensional particle tracking velocimetry (SC3D-PTV), an image-based, single-camera technique for measuring 3-component, volumetric velocity fields in environments with limited optical access, in particular, optically accessible internal combustion engines. The optical components used for SC3D-PTV are similar to those used for two-camera stereoscopic-µPIV, but are adapted to project two simultaneous images onto a single image sensor. A novel PTV algorithm relying on the similarity of the particle images corresponding to a single, physical particle produces 3-component, volumetric velocity fields, rather than the 3-component, planar results obtained with stereoscopic PIV, and without the reconstruction of an instantaneous 3D particle field. The hardware and software used for SC3D-PTV are described, and experimental results are presented.

  1. Turbulent mixing in three-dimensional droplet arrays

    International Nuclear Information System (INIS)

    Zoby, M.R.G.; Navarro-Martinez, S.; Kronenburg, A.; Marquis, A.J.

    2011-01-01

    The atomisation, evaporation and subsequent mixing of fuel from a liquid spray determines the effectiveness of the combustion processes in gas turbines and internal combustion engines. In the present paper, three-dimensional direct numerical simulations (DNS) of the evaporation of methanol droplets in hot environments are presented. The gas phase mixing is assessed by examining the scalar dissipation and the mixture fraction probability density function (PDF). Novel multi-conditional models are proposed that use mixture fraction and structural parameters as the conditioning variables for the scalar dissipation which is found to be well predicted in terms of magnitude and distribution. The β-PDF description of the mixture fraction seems to capture well the global behaviour for a laminar environment and for time-averaged results in turbulent cases. A novel model for the mixture fraction PDF is also proposed based on the multi-conditional model for scalar dissipation and an accurate representation of the PDF is achieved.

  2. Three-dimensional structural characterization of nonwoven fabrics.

    Science.gov (United States)

    Venu, Lalith B Suragani; Shim, Eunkyoung; Anantharamaiah, Nagendra; Pourdeyhimi, Behnam

    2012-12-01

    Nonwoven materials are found in a gamut of critical applications. This is partly due to the fact that these structures can be produced at high speed and engineered to deliver unique functionality at low cost. The behavior of these materials is highly dependent on alignment of fibers within the structure. The ability to characterize and also to control the structure is important, but very challenging due to the complex nature of the structures. Thus, to date, focus has been placed mainly on two-dimensional analysis techniques for describing the behavior of nonwovens. This article demonstrates the utility of three-dimensional (3D) digital volumetric imaging technique for visualizing and characterizing a complex 3D class of nonwoven structures produced by hydroentanglement.

  3. Panoramic three-dimensional CT imaging

    International Nuclear Information System (INIS)

    Kawamata, Akitoshi; Fujishita, Masami

    1998-01-01

    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)

  4. 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.

  5. Three-Dimensional Coculture of Meniscal Cells and Mesenchymal Stem Cells in Collagen Type I Hydrogel on a Small Intestinal Matrix-A Pilot Study Toward Equine Meniscus Tissue Engineering.

    Science.gov (United States)

    Kremer, Antje; Ribitsch, Iris; Reboredo, Jenny; Dürr, Julia; Egerbacher, Monika; Jenner, Florien; Walles, Heike

    2017-05-01

    Meniscal injuries are the most frequently encountered soft tissue injuries in the equine stifle joint. Due to the inherent limited repair potential of meniscal tissue, meniscal injuries do not only affect the meniscus itself but also lead to impaired joint homeostasis and secondary osteoarthritis. The presented study compares 3D coculture constructs of primary equine mesenchymal stem cells (MSC) and meniscus cells (MC) seeded on three different scaffolds-a cell-laden collagen type I hydrogel (Col I gel), a tissue-derived small intestinal matrix scaffold (SIS-muc) and a combination thereof-for their qualification to be applied for meniscus tissue engineering. To investigate cell attachment of primary MC and MSC on SIS-muc matrix SEM pictures were performed. For molecular analysis, lyophilized samples of coculture constructs with different cell ratios (100% MC, 100% MSC, and 50% MC and 50% MSC, 20% MC, and 80% MSC) were digested and analyzed for DNA and GAG content. Active matrix remodeling of 3D coculture models was indicated by matrix metalloproteinases detection. For comparison of tissue-engineered constructs with the histologic architecture of natural equine menisci, paired lateral and medial menisci of 15 horses representing different age groups were examined. A meniscus phenotype with promising similarity to native meniscus tissue in its GAG/DNA expression in addition to Col I, Col II, and Aggrecan production was achieved using a scaffold composed of Col I gel on SIS-muc combined with a coculture of MC and MSC. The results encourage further development of this scaffold-cell combination for meniscus tissue engineering.

  6. [Precision of three-dimensional printed brackets].

    Science.gov (United States)

    Zhang, D; Wang, L C; Zhou, Y H; Liu, X M; Li, J

    2017-08-18

    This study was based on digital orthodontic diagnosis work flow for indirect bonding transfer tray model design and three-dimensional (3D) printing, and the aim of this paper was to inspect the dimensional accuracyof 3D printed brackets, which is the foundation of the follow up work and hoped that will illuminate the clinical application of the digital orthodontics work flow. The samples which consisted of 14 cases of patients with malocclusion from Department of Orthodontics Peking University were selected, including 8 cases with tooth extraction and 6 cases without tooth extraction. All the 14 patients were taken intra-oral scan (Trios 3Shape, Denmark) and cone-beam computed tomography (CBCT, NewTom 3G volumetric scanner, Aperio Service,Italy)shooting after periodontal treatment. STL data and DICOM data were obtained from intraoral scans and CBCT images.Data segmentation, registration, fusion, automatic tooth arrangement, virtual positioning of orthodontic appliance and conversion the coordinates of malocclusion model were all done with self-programming software. The data of 3D printing model with brackets on it were output finally and printed out with EDEN260V (Objet Geometries, Israel) to make indirect bonding transfer tray. Digital vernier caliper was used to measure the length and width of upper and lower left brackets and buccal tubes on those 3D models after removal of surrounding supporting material by ultrasonic vibration and water-spray. Intra-examiner reliability was assessed by using intra-class correlation coefficients (ICC), and one-sample T test was used to compare the measurements with the standard dimensional data of the brackets. There were significant differences which range in 0.04-0.17 mm between the 13 items out of the 19 measurement items. Except for the length of the lower left premolars'brackets, mean values of the other items were greater than the test value. Although the measurement results in the width of brackets and the width and

  7. 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

  8. The three-dimensional matrix -- An evolution in project management

    Energy Technology Data Exchange (ETDEWEB)

    Glidewell, D.

    1996-09-01

    In the Functional Department Dimension, functional departments such as project management, design, and construction would be maintained to maximize consistency among project teams, evenly allocate training opportunities, and facilitate the crossfeeding of lessons learned and innovative ideas. Functional departments were also determined to be the surest way of complying uniformly with all project control systems required by the Department of Energy (Sandia`s primary external customer). The Technical Discipline dimension was maintained to enhance communication within the technical disciplines, such as electrical engineering, mechanical engineering, civil engineering, etc., and to evenly allocate technical training opportunities, reduce technical obsolescence, and enhance design standards. The third dimension, the Project Dimension, represents the next step in the project management evolution at Sandia, and together with Functional Department and Technical Discipline Dimensions constitutes the three-dimensional matrix. It is this Project Dimension that will be explored thoroughly in this paper, including a discussion of the specific roles and responsibilities of both management and the project team.

  9. The Three-dimensional Digital Factory for Shipbuilding Technology Research

    Directory of Open Access Journals (Sweden)

    Xu Wei

    2016-01-01

    Full Text Available The three-dimensional digital factory technology research is the hotspot in shipbuilding recently. The three-dimensional digital factory technology not only focus on design the components of the product, but also discuss on the simulation and analyses of the production process.Based on the three-dimensional model, the basic data layer, application control layer and the presentation layer of hierarchical structure are established in the three-dimensional digital factory of shipbuilding in this paper. And the key technologies of three-dimensional digital factory of shipbuilding are analysed. Finally, a case study is applied and the results show that the three-dimensional digital factory will play an important role in the future.

  10. Three-dimensional optofluidic device for isolating microbes

    Science.gov (United States)

    Keloth, A.; Paterson, L.; Markx, G. H.; Kar, A. K.

    2015-03-01

    Development of efficient methods for isolation and manipulation of microorganisms is essential to study unidentified and yet-to-be cultured microbes originating from a variety of environments. The discovery of novel microbes and their products have the potential to contribute to the development of new medicines and other industrially important bioactive compounds. In this paper we describe the design, fabrication and validation of an optofluidic device capable of redirecting microbes within a flow using optical forces. The device holds promise to enable the high throughput isolation of single microbes for downstream culture and analysis. Optofluidic devices are widely used in clinical research, cell biology and biomedical engineering as they are capable of performing analytical functions such as controlled transportation, compact and rapid processing of nanolitres to millilitres of clinical or biological samples. We have designed and fabricated a three dimensional optofluidic device to control and manipulate microorganisms within a microfluidic channel. The device was fabricated in fused silica by ultrafast laser inscription (ULI) followed by selective chemical etching. The unique three-dimensional capability of ULI is utilized to integrate microfluidic channels and waveguides within the same substrate. The main microfluidic channel in the device constitutes the path of the sample. Optical waveguides are fabricated at right angles to the main microfluidic channel. The potential of the optical scattering force to control and manipulate microorganisms is discussed in this paper. A 980 nm continuous wave (CW) laser source, coupled to the waveguide, is used to exert radiation pressure on the particle and particle migrations at different flow velocities are recorded. As a first demonstration, device functionality is validated using fluorescent microbeads and initial trials with microalgae are presented.

  11. Three dimensional visualization breakthrough in analysis and communication of technical information for nuclear waste management

    Energy Technology Data Exchange (ETDEWEB)

    Alexander, D.H.; Cerny, B.A. [USDOE, Washington, DC (USA); Hill, E.R.; Krupka, K.M. [Pacific Northwest Lab., Washington, DC (USA); Smoot, J.L. [Pacific Northwest Lab., Richland, WA (USA); Smith, D.R.; Waldo, K. [Dynamic Graphics, Inc., Bethesda, MD (USA)

    1990-11-01

    Computer graphics systems that provide interactive display and manipulation of three-dimensional data are powerful tools for the analysis and communication of technical information required for characterization and design of a geologic repository for nuclear waste. Greater understanding of site performance and repository design information is possible when performance-assessment modeling results can be visually analyzed in relation to site geologic and hydrologic information and engineering data for surface and subsurface facilities. In turn, this enhanced visualization capability provides better communication between technical staff and program management with respect to analysis of available information and prioritization of program planning. A commercially-available computer system was used to demonstrate some of the current technology for three-dimensional visualization within the architecture of systems for nuclear waste management. This computer system was used to interactively visualize and analyze the information for two examples: (1) site-characterization and engineering data for a potential geologic repository at Yucca Mountain, Nevada; and (2) three-dimensional simulations of a hypothetical release and transport of contaminants from a source of radionuclides to the vadose zone. Users may assess the three-dimensional distribution of data and modeling results by interactive zooming, rotating, slicing, and peeling operations. For those parts of the database where information is sparse or not available, the software incorporates models for the interpolation and extrapolation of data over the three-dimensional space of interest. 12 refs., 4 figs.

  12. Accuracy of three-dimensional seismic ground response analysis in time domain using nonlinear numerical simulations

    Science.gov (United States)

    Liang, Fayun; Chen, Haibing; Huang, Maosong

    2017-07-01

    To provide appropriate uses of nonlinear ground response analysis for engineering practice, a three-dimensional soil column with a distributed mass system and a time domain numerical analysis were implemented on the OpenSees simulation platform. The standard mesh of a three-dimensional soil column was suggested to be satisfied with the specified maximum frequency. The layered soil column was divided into multiple sub-soils with a different viscous damping matrix according to the shear velocities as the soil properties were significantly different. It was necessary to use a combination of other one-dimensional or three-dimensional nonlinear seismic ground analysis programs to confirm the applicability of nonlinear seismic ground motion response analysis procedures in soft soil or for strong earthquakes. The accuracy of the three-dimensional soil column finite element method was verified by dynamic centrifuge model testing under different peak accelerations of the earthquake. As a result, nonlinear seismic ground motion response analysis procedures were improved in this study. The accuracy and efficiency of the three-dimensional seismic ground response analysis can be adapted to the requirements of engineering practice.

  13. Three dimensional visualization breakthrough in analysis and communication of technical information for nuclear waste management

    International Nuclear Information System (INIS)

    Alexander, D.H.; Cerny, B.A.; Hill, E.R.; Krupka, K.M.; Smoot, J.L.; Smith, D.R.; Waldo, K.

    1990-11-01

    Computer graphics systems that provide interactive display and manipulation of three-dimensional data are powerful tools for the analysis and communication of technical information required for characterization and design of a geologic repository for nuclear waste. Greater understanding of site performance and repository design information is possible when performance-assessment modeling results can be visually analyzed in relation to site geologic and hydrologic information and engineering data for surface and subsurface facilities. In turn, this enhanced visualization capability provides better communication between technical staff and program management with respect to analysis of available information and prioritization of program planning. A commercially-available computer system was used to demonstrate some of the current technology for three-dimensional visualization within the architecture of systems for nuclear waste management. This computer system was used to interactively visualize and analyze the information for two examples: (1) site-characterization and engineering data for a potential geologic repository at Yucca Mountain, Nevada; and (2) three-dimensional simulations of a hypothetical release and transport of contaminants from a source of radionuclides to the vadose zone. Users may assess the three-dimensional distribution of data and modeling results by interactive zooming, rotating, slicing, and peeling operations. For those parts of the database where information is sparse or not available, the software incorporates models for the interpolation and extrapolation of data over the three-dimensional space of interest. 12 refs., 4 figs

  14. Uncalibrated Three-Dimensional Microrobot Control

    Science.gov (United States)

    2016-05-11

    Professor Jenelle A. Piepmeier Weapons and Systems Engineering Department...microrobot to the target position without any prior knowledge of the system parameters such as electromagnetic field strengths, drag coefficients, or...intrinsic and extrinsic camera parameters. 15. SUBJECT TERMS Biomedical Microelectromechanical Systems, Robot Control, Electromagnetics , Visual

  15. Three-dimensional reconstruction of the biliary tract using spiral computed tomography. Three-dimensional cholangiography

    International Nuclear Information System (INIS)

    Gon, Masanori; Ogura, Norihiro; Uetsuji, Shouji; Ueyama, Yasuo

    1995-01-01

    In this study, 310 patients with benign biliary diseases, 20 with gallbladder cancer, and 8 with biliary tract carcinoma underwent spiral CT (SCT) scanning at cholangiography. Depiction rate of the shape of the conjunction site of the gallbladder and biliary tract was 27.5% by conventional intravenous cholangiography (DIC), 92.5% by ERC, and 90.0% by DIC-SCT. Abnormal cystic duct course was admitted in 14.1%. Multiplanar reconstruction by DIC-SCT enabled identification of the common bile duct and intrahepatic bile duct stone. Three-dimensional reconstruction of DIC-SCT was effective in evaluating obstruction of the anastomosis or passing condition of after hepatico-jejunostomy. Two-dimensional SCT images through PTCD tube enabled degree of hepatic invasion in bile duct cancer, and three-dimensional images were useful in grasping the morphology of the bile duct branches near the obstruction site. DIC-SCT is therefore considered a useful procedure as non-invasive examination of bile duct lesions. (S.Y.)

  16. Three-dimensional simulation studies of 10 MeV, 352.2 MHz drift ...

    Indian Academy of Sciences (India)

    at 352.2 MHz with a maximum duty cycle of 3%. The DTL tank will consist of ... The three-dimensional (3D) design of the DTL is done using CST microwave studio (CST MWS) incorporating the various non- ..... Based on the physics design, engineering design is done for the first segment and fab- rication is being taken up.

  17. Scaling up Three-Dimensional Science Learning through Teacher-Led Study Groups across a State

    Science.gov (United States)

    Reiser, Brian J.; Michaels, Sarah; Moon, Jean; Bell, Tara; Dyer, Elizabeth; Edwards, Kelsey D.; McGill, Tara A. W.; Novak, Michael; Park, Aimee

    2017-01-01

    The vision for science teaching in the Framework for K-12 Science Education and the Next Generation Science Standards requires a radical departure from traditional science teaching. Science literacy is defined as three-dimensional (3D), in which students engage in science and engineering practices to develop and apply science disciplinary ideas…

  18. Technical Development of Slurry Three-Dimensional Printer

    Science.gov (United States)

    Jiang, Cho-Pei; Hsu, Huang-Jan; Lee, Shyh-Yuan

    2017-09-01

    The aim of this paper is to review the technical development of slurry three-dimensional printer (3DP) which based on photo-polymerization and constrained surface method. Basically, slurry consists of ceramic powder, resin and photo-initiator. The light engines for solidifying the photo-curable slurry can be classified as laser, liquid crystal panel (LCD), digital light processing (DLP). The slurry can be reacted and solidified by selective ray according to the reaction spectrum of photo-initiator. Ceramic powder used in this study is zirconia oxide. Experimental results show that ceramic particle size affects the viscosity of slurry severely resulting in low accuracy and the occurrence of micro crack in the layer casting procedure. Therefore, the effect of particle size on the curability and accuracy of built green part is discussed. A single dental crown is proposed to be fabricated by these three light engines as a benchmark for comparison. In addition, the cost and the limitation are compared in the aspect of dental crown fabrication. Consequently, the lowest cost is LCD-type slurry 3DP system. DLP-type slurry 3DP can produce green body with the fastest fabrication time. The volumetric error of sintered part that made by these three fabrication methods is similar because the composition of slurry is the same.

  19. Three-dimensional inkjet biofabrication based on designed images

    International Nuclear Information System (INIS)

    Arai, Kenichi; Iwanaga, Shintaroh; Toda, Hideki; Genci, Capi; Nakamura, Makoto; Nishiyama, Yuichi

    2011-01-01

    Tissue engineering has been developed with the ultimate aim of manufacturing human organs, but success has been limited to only thin tissues and tissues with no significant structures. In order to construct more complicated tissues, we have developed a three-dimensional (3D) fabrication technology in which 3D structures are directly built up by layer-by-layer printing with living cells and several tissue components. We developed a custom-made inkjet printer specially designed for this purpose. Recently, this printer was improved, and the on-demand printing mode was developed and installed to fabricate further complicated structures. As a result of this version, 3D layer-by-layer printing based on complicated image data has become possible, and several 2D and 3D structures with more complexity than before were successfully fabricated. The effectiveness of the on-demand printing mode in the fabrication of complicated 3D tissue structures was confirmed. As complicated 3D structures are essential for biofunctional tissues, inkjet 3D biofabrication has great potential for engineering complicated bio-functional tissues.

  20. Three-dimensional inkjet biofabrication based on designed images

    Energy Technology Data Exchange (ETDEWEB)

    Arai, Kenichi; Iwanaga, Shintaroh; Toda, Hideki; Genci, Capi; Nakamura, Makoto [Graduate School of Science and Engineering, University of Toyama, 3190 Gofuku, Toyama 930-8555 (Japan); Nishiyama, Yuichi, E-mail: maknaka@eng.u-toyama.ac.jp [Bioprinting Project of Kanagawa Academy of Science and Technology, Kawasaki (Japan)

    2011-09-15

    Tissue engineering has been developed with the ultimate aim of manufacturing human organs, but success has been limited to only thin tissues and tissues with no significant structures. In order to construct more complicated tissues, we have developed a three-dimensional (3D) fabrication technology in which 3D structures are directly built up by layer-by-layer printing with living cells and several tissue components. We developed a custom-made inkjet printer specially designed for this purpose. Recently, this printer was improved, and the on-demand printing mode was developed and installed to fabricate further complicated structures. As a result of this version, 3D layer-by-layer printing based on complicated image data has become possible, and several 2D and 3D structures with more complexity than before were successfully fabricated. The effectiveness of the on-demand printing mode in the fabrication of complicated 3D tissue structures was confirmed. As complicated 3D structures are essential for biofunctional tissues, inkjet 3D biofabrication has great potential for engineering complicated bio-functional tissues.

  1. Santiago Ramón y Cajal and three-dimensional cinema.

    Science.gov (United States)

    Santarén, Juan Fernández

    2015-01-01

    In this article, I present and comment on two unpublished letters written by the Spanish engineer Carlos Mendizábal Brunet to Santiago Ramón y Cajal informing him of the development of a new device for three-dimensional cinema and asking for his approval. Fortunately, the answers given by Cajal to these two letters have also been preserved, and they reveal his interest in three-dimensional cinema; in the letters, he reported that he himself had designed a prototype capable of creating on a screen a feeling of 3-D relief, a subject about which he was always passionate.

  2. Three-dimensional low-energy topological invariants

    International Nuclear Information System (INIS)

    Bakalarska, M.; Broda, B.

    2000-01-01

    A description of the one-loop approximation formula for the partition function of a three-dimensional abelian version of the Donaldson-Witten theory is proposed. The one-loop expression is shown to contain such topological invariants of a three-dimensional manifold M like the Reidemeister-Ray-Singer torsion τ R and Betti numbers. (orig.)

  3. 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....

  4. Three dimensional reductions of four-dimensional quasilinear systems

    Science.gov (United States)

    Pavlov, Maxim V.; Stoilov, Nikola M.

    2017-11-01

    In this paper, we show that four-dimensional quasilinear systems of first order integrable by the method of two-dimensional hydrodynamic reductions possess infinitely many three-dimensional hydrodynamic reductions, which are also integrable systems. These three-dimensional multi-component integrable systems are irreducible to two-dimensional hydrodynamic reductions in a generic case.

  5. 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.

  6. Three-dimensional plasma equilibrium near a separatrix

    International Nuclear Information System (INIS)

    Reiman, A.H.; Pomphrey, N.; Boozer, A.H.

    1988-08-01

    The limiting behavior of a general three-dimensional MHD equilibrium near a separatrix is calculated explicitly. No expansions in β or assumptions about island widths are made. Implications of the results for the numerical calculation of such equilibria, are discussed, as well as for issues concerning the existence of three-dimensional MHD equilibria. 16 refs., 2 figs

  7. Three dimensional periodic foundations for base seismic isolation

    International Nuclear Information System (INIS)

    Yan, Y; Mo, Y L; Cheng, Z; Shi, Z; Menq, F; Tang, Y

    2015-01-01

    Based on the concept of phononic crystals, periodic foundations made of periodic materials are investigated in this paper. The periodic foundations can provide low frequency band gaps, which cover the main frequency ranges of seismic waves. Therefore, the periodic foundations are able to protect the upper structures during earthquake events. In this paper, the basic theory of three dimensional periodic foundations is studied and the finite element method was used to conduct the sensitivity study. A simplified three-dimensional periodic foundation with a superstructure was tested in the field and the feasibility of three dimensional periodic foundations was proved. The test results showed that the response of the upper structure with the three dimensional periodic foundation was reduced under excitation waves with the main frequency falling in the attenuation zones. The finite element analysis results are consistent with the experimental data, indicating that three dimensional periodic foundations are a feasible way of reducing seismic vibrations. (paper)

  8. Characterizing College Science Assessments: The Three-Dimensional Learning Assessment Protocol.

    Science.gov (United States)

    Laverty, James T; Underwood, Sonia M; Matz, Rebecca L; Posey, Lynmarie A; Carmel, Justin H; Caballero, Marcos D; Fata-Hartley, Cori L; Ebert-May, Diane; Jardeleza, Sarah E; Cooper, Melanie M

    2016-01-01

    Many calls to improve science education in college and university settings have focused on improving instructor pedagogy. Meanwhile, science education at the K-12 level is undergoing significant changes as a result of the emphasis on scientific and engineering practices, crosscutting concepts, and disciplinary core ideas. This framework of "three-dimensional learning" is based on the literature about how people learn science and how we can help students put their knowledge to use. Recently, similar changes are underway in higher education by incorporating three-dimensional learning into college science courses. As these transformations move forward, it will become important to assess three-dimensional learning both to align assessments with the learning environment, and to assess the extent of the transformations. In this paper we introduce the Three-Dimensional Learning Assessment Protocol (3D-LAP), which is designed to characterize and support the development of assessment tasks in biology, chemistry, and physics that align with transformation efforts. We describe the development process used by our interdisciplinary team, discuss the validity and reliability of the protocol, and provide evidence that the protocol can distinguish between assessments that have the potential to elicit evidence of three-dimensional learning and those that do not.

  9. A study on three dimensional layout design by the simulated annealing method

    International Nuclear Information System (INIS)

    Jang, Seung Ho

    2008-01-01

    Modern engineered products are becoming increasingly complicated and most consumers prefer compact designs. Layout design plays an important role in many engineered products. The objective of this study is to suggest a method to apply the simulated annealing method to the arbitrarily shaped three-dimensional component layout design problem. The suggested method not only optimizes the packing density but also satisfies constraint conditions among the components. The algorithm and its implementation as suggested in this paper are extendable to other research objectives

  10. Protein Fibrillar Hydrogels for three-Dimensional Tissue Engineering

    Directory of Open Access Journals (Sweden)

    Hui Yan

    2009-01-01

    Full Text Available Protein self-assembly into highly ordered fibrillar aggregates has attracted increasing attention over recent years, due primarily to its association with disease states such as Alzheimer's. More recently, however, research has focused on understanding the generic behavior of protein self-assembly where fibrillation is typically induced under harsh conditions of low pH and/or high temperature. Moreover the inherent properties of these fibrils, including their nanoscale dimension, environmental responsiveness, and biological compatibility, are attracting substantial interest for exploiting these fibrils for the creation of new materials. Here we will show how protein fibrils can be formed under physiological conditions and their subsequent gelation driven using the ionic strength of cell culture media while simultaneously incorporating cells homogeneously throughout the gel network. The fibrillar and elastic nature of the gel have been confirmed using cryo-transmission electron microscopy and oscillatory rheology, respectively; while cell culture work shows that our hydrogels promote cell spreading, attachment, and proliferation in three dimensions.

  11. Three-dimensional optical techniques using Dammann gratings

    Science.gov (United States)

    Zhou, Changhe; Yu, Junjie; Wang, Shaoqing; Wei, Shengbin

    2012-11-01

    This paper summarized our work on three-dimensional optical technologies using Dammann gratings, e.g., threedimnensional Dammann gratings, three dimensional imaging using a Dammann grating, etc.. We developed threedimensional Dammann grating which can produce three-dimensional array with equal distance and equal intensity with a high-numerical-aperture lens. As we know, a lens usually has a single focal point. Fresnel zone plate can generate several axial focal points, but the intensity between them is unequal. By introducing the concept of Dammann grating into the circular phase plate, we invented Dammann zone plate(DZP) which can produce a series of axial focal points with equal intensity. Combining DZP with a Dammann grating, three-dimensional Dammann array will be generated, which is highly interesting for various applications. We also built a three-dimensional measuring system using a Dammann grating, with two cameras as the right eye and right eye, respectively. We used a 64×64 Dammann grating for generation of a square array of light spots for parallel capturing the three-dimensional profile of an object. The two cameras and the illuminating part are packaged together. After scanning the object, its three-dimensional profile will be obtained. Experimental results demonstrated the effectiveness of this technique.

  12. Turbulent Flows Over Three-Dimensional Shark Skin

    Science.gov (United States)

    Boomsma, Aaron; Wen, Li; Lauder, George; Sotiropoulos, Fotis

    2012-11-01

    Shark skin is covered with thousands of small tooth-like structures called denticles. It has long been hypothesized that denticles act as riblets do in a turbulent boundary layer and help reduce friction drag and enhance shark swimming efficiency. We employ the Curvilinear Immersed Boundary (CURVIB) method (Ge and Sotiropoulos, J. Comp. Physics, 2008) to carry out high-resolution large eddy simulations of turbulent flow past a series of anatomically realistic shark denticles mounted on a flat plate. The denticle shapes used in our simulations were obtained by scanning Mako Short Fin shark skin with micro-CT. The computed results are analyzed to elucidate the three-dimensional structure of the flow past the denticles and identify possible drag reduction mechanics. Drag measurements obtained in a laboratory flume for various denticle spacings and arrangements are also reported and analyzed in tandem with the LES results to explore similarities between shark skin and engineered riblets. Computational Resources were provided by the University of Minnesota Supercomputing Institute.

  13. Three-dimensional facial digitization using advanced digital image correlation.

    Science.gov (United States)

    Nguyen, Hieu; Kieu, Hien; Wang, Zhaoyang; Le, Hanh N D

    2018-03-20

    Presented in this paper is an effective technique to acquire the three-dimensional (3D) digital images of the human face without the use of active lighting and artificial patterns. The technique is based on binocular stereo imaging and digital image correlation, and it includes two key steps: camera calibration and image matching. The camera calibration involves a pinhole model and a bundle-adjustment approach, and the governing equations of the 3D digitization process are described. For reliable pixel-to-pixel image matching, the skin pores and freckles or lentigines on the human face serve as the required pattern features to facilitate the process. It employs feature-matching-based initial guess, multiple subsets, iterative optimization algorithm, and reliability-guided computation path to achieve fast and accurate image matching. Experiments have been conducted to demonstrate the validity of the proposed technique. The simplicity of the approach and the affordable cost of the implementation show its practicability in scientific and engineering applications.

  14. Three-dimensional digital reconstruction of skin epidermis and dermis.

    Science.gov (United States)

    Liu, P; Zhu, J-Y; Tang, B; Hu, Z-C

    2018-05-01

    This study describes how three-dimensional (3D) human skin tissue is reconstructed, and provides digital anatomical data for the physiological structure of human skin tissue based on large-scale thin serial sections. Human skin samples embedded in paraffin were cut serially into thin sections and then stained with hematoxylin-eosin. Images of serial sections obtained from lighting microscopy were scanned and aligned by the scale-invariant feature transform algorithm. 3D reconstruction of the skin tissue was generated using Mimics software. Fibre content, porosity, average pore diameter and specific surface area of dermis were analysed using the ImageJ analysis system. The root mean square error and mutual information based on the scale-invariant feature transform algorithm registration were significantly greater than those based on the manual registration. Fibre distribution gradually decreased from top to bottom; while porosity showed an opposite trend with irregular average pore diameter distribution. A specific surface area of the dermis showed a 'V' shape trend. Our data suggested that 3D reconstruction of human skin tissue based on large-scale serial sections could be a valuable tool for providing a highly accurate histological structure for analysis of skin tissue. Moreover, this technology could be utilized to produce tissue-engineered skin via a 3D bioprinter in the future. © 2017 The Authors Journal of Microscopy © 2017 Royal Microscopical Society.

  15. Self-assembled three dimensional network designs for soft electronics.

    Science.gov (United States)

    Jang, Kyung-In; Li, Kan; Chung, Ha Uk; Xu, Sheng; Jung, Han Na; Yang, Yiyuan; Kwak, Jean Won; Jung, Han Hee; Song, Juwon; Yang, Ce; Wang, Ao; Liu, Zhuangjian; Lee, Jong Yoon; Kim, Bong Hoon; Kim, Jae-Hwan; Lee, Jungyup; Yu, Yongjoon; Kim, Bum Jun; Jang, Hokyung; Yu, Ki Jun; Kim, Jeonghyun; Lee, Jung Woo; Jeong, Jae-Woong; Song, Young Min; Huang, Yonggang; Zhang, Yihui; Rogers, John A

    2017-06-21

    Low modulus, compliant systems of sensors, circuits and radios designed to intimately interface with the soft tissues of the human body are of growing interest, due to their emerging applications in continuous, clinical-quality health monitors and advanced, bioelectronic therapeutics. Although recent research establishes various materials and mechanics concepts for such technologies, all existing approaches involve simple, two-dimensional (2D) layouts in the constituent micro-components and interconnects. Here we introduce concepts in three-dimensional (3D) architectures that bypass important engineering constraints and performance limitations set by traditional, 2D designs. Specifically, open-mesh, 3D interconnect networks of helical microcoils formed by deterministic compressive buckling establish the basis for systems that can offer exceptional low modulus, elastic mechanics, in compact geometries, with active components and sophisticated levels of functionality. Coupled mechanical and electrical design approaches enable layout optimization, assembly processes and encapsulation schemes to yield 3D configurations that satisfy requirements in demanding, complex systems, such as wireless, skin-compatible electronic sensors.

  16. Fabrication of three-dimensional nanofibrous macrostructures by electrospinning

    Directory of Open Access Journals (Sweden)

    Ping Zhu

    2016-05-01

    Full Text Available Electrospinning has been widely used in fabricating nanofibers and nanofibrous membranes. Recently, the fabrication of three-dimensional (3D nanofibrous macrostructures has become a hot subject in the development of electrospinning technology. In this paper, the 3D nanofibrous macrostructure was constructed by using electrospinning apparatus with both dynamic and static 3D collecting templates. The effect of the governing parameters on the formation process of 3D macrostructure is studied, such as the applied voltage, the flow rate, the needle-tip-to-collector distance, and the rotating speed. It was found that laying the collecting device either in parallel or perpendicularly with some gap in between, would lead to orderly deposition of nanofibers. In this study, a “dumbbell” dynamic collector was used to fabricate special 3D macrostructures consisting of multilayers of fibrous membranes. By adjusting the rotating speed of the collector, the formation process of multilayer 3D macrostructure can be controlled. An umbrella-shaped static structure collector was used to fabricate 3D framework structures. It is feasible to fabricate various 3D nanofibrous structures via electrospinning with 3D collecting templates, which has great potential in tissue engineering.

  17. Three-dimensional cell culture technique and pathophysiology.

    Science.gov (United States)

    Matsusaki, Michiya; Case, Charles Patrick; Akashi, Mitsuru

    2014-07-01

    Three-dimensional (3D) tissue constructs consisting of human cells have opened a new avenue for tissue engineering, pharmaceutical and pathophysiological applications, and have great potential to estimate the dynamic pharmacological effects of drug candidates, metastasis processes of cancer cells, and toxicity expression of nano-materials, as a 3D-human tissue model instead of in vivo animal experiments. However, most 3D-cellular constructs are a cell spheroid, which is a heterogeneous aggregation, and thus the reconstruction of the delicate and precise 3D-location of multiple types of cells is almost impossible. In recent years, various novel technologies to develop complex 3D-human tissues including blood and lymph capillary networks have demonstrated that physiological human tissue responses can be replicated in the nano/micro-meter ranges. Here, we provide a brief overview on current 3D-tissue fabrication technologies and their biomedical applications. 3D-human tissue models will be a powerful technique for pathophysiological applications. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. Three Dimensional CFD Analysis of the GTX Combustor

    Science.gov (United States)

    Steffen, C. J., Jr.; Bond, R. B.; Edwards, J. R.

    2002-01-01

    The annular combustor geometry of a combined-cycle engine has been analyzed with three-dimensional computational fluid dynamics. Both subsonic combustion and supersonic combustion flowfields have been simulated. The subsonic combustion analysis was executed in conjunction with a direct-connect test rig. Two cold-flow and one hot-flow results are presented. The simulations compare favorably with the test data for the two cold flow calculations; the hot-flow data was not yet available. The hot-flow simulation Indicates that the conventional ejector-ramjet cycle would not provide adequate mixing at the conditions tested. The supersonic combustion ramjet flowfield was simulated with frozen chemistry model. A five-parameter test matrix was specified, according to statistical design-of-experiments theory. Twenty-seven separate simulations were used to assemble surrogate models for combustor mixing efficiency and total pressure recovery. Scramjet injector design parameters (injector angle, location, and fuel split) as well as mission variables (total fuel mass flow and freestream Mach number) were included in the analysis. A promising injector design has been identified that provides good mixing characteristics with low total pressure losses. The surrogate models can be used to develop performance maps of different injector designs. Several complex three-way variable interactions appear within the dataset that are not adequately resolved with the current statistical analysis.

  19. Self-assembled three dimensional network designs for soft electronics

    Science.gov (United States)

    Jang, Kyung-In; Li, Kan; Chung, Ha Uk; Xu, Sheng; Jung, Han Na; Yang, Yiyuan; Kwak, Jean Won; Jung, Han Hee; Song, Juwon; Yang, Ce; Wang, Ao; Liu, Zhuangjian; Lee, Jong Yoon; Kim, Bong Hoon; Kim, Jae-Hwan; Lee, Jungyup; Yu, Yongjoon; Kim, Bum Jun; Jang, Hokyung; Yu, Ki Jun; Kim, Jeonghyun; Lee, Jung Woo; Jeong, Jae-Woong; Song, Young Min; Huang, Yonggang; Zhang, Yihui; Rogers, John A.

    2017-06-01

    Low modulus, compliant systems of sensors, circuits and radios designed to intimately interface with the soft tissues of the human body are of growing interest, due to their emerging applications in continuous, clinical-quality health monitors and advanced, bioelectronic therapeutics. Although recent research establishes various materials and mechanics concepts for such technologies, all existing approaches involve simple, two-dimensional (2D) layouts in the constituent micro-components and interconnects. Here we introduce concepts in three-dimensional (3D) architectures that bypass important engineering constraints and performance limitations set by traditional, 2D designs. Specifically, open-mesh, 3D interconnect networks of helical microcoils formed by deterministic compressive buckling establish the basis for systems that can offer exceptional low modulus, elastic mechanics, in compact geometries, with active components and sophisticated levels of functionality. Coupled mechanical and electrical design approaches enable layout optimization, assembly processes and encapsulation schemes to yield 3D configurations that satisfy requirements in demanding, complex systems, such as wireless, skin-compatible electronic sensors.

  20. Cylindrical Three-Dimensional Porous Anodic Alumina Networks

    Directory of Open Access Journals (Sweden)

    Pedro M. Resende

    2016-11-01

    Full Text Available The synthesis of a conformal three-dimensional nanostructure based on porous anodic alumina with transversal nanopores on wires is herein presented. The resulting three-dimensional network exhibits the same nanostructure as that obtained on planar geometries, but with a macroscopic cylindrical geometry. The morphological analysis of the nanostructure revealed the effects of the initial defects on the aluminum surface and the mechanical strains on the integrity of the three-dimensional network. The results evidence the feasibility of obtaining 3D porous anodic alumina on non-planar aluminum substrates.

  1. Fusion of three-dimensional X-ray angiography and three-dimensional echocardiography

    International Nuclear Information System (INIS)

    Rasche, Volker; Mansour, Moussa; Reddy, Vivek; Singh, Jagmeet P.; Ruskin, Jeremy; Qureshi, Answer; Manzke, Robert; Sokka, Sham

    2008-01-01

    Cardiovascular intervention guidance requires knowledge of heart function relative to its blood supply or venous drainage. Functional and vascular anatomic data are usually generated on different imaging systems, so fusion of the data is necessary to simultaneously visualize the results for intervention planning and guidance. The objective of this work is to establish the feasibility of fusing volumetric ultrasound (U/S) data with three-dimensional (3D) X-ray imaging data for visualization of cardiac morphology, function and coronary venous drainage. Temporally resolved U/S volume data was registered with the 3D reconstruction of vascular structures derived from X-ray modeling and reconstruction. U/S image registration was obtained by optical tracking fiducial markers with simultaneous X-ray imaging. The proposed technique was applied to phantom data for accuracy assessment of the registration process and to biventricular pacemaker implantation as clinical example. Fusion of U/S data with 3D X-ray reconstruction data produced an RMS registration error below 2 mm. Preliminary clinical feasibility of U/S-derived data synchronously with X-ray derived 3D coronary venography was established. This technique can be applied for fusion of functional U/S data with 3D anatomic X-ray data of the coronary veins during a biventricular pacemaker implantation procedures. (orig.)

  2. Fabrication of malleable three-dimensional-printed customized bolus using three-dimensional scanner.

    Directory of Open Access Journals (Sweden)

    Jae Won Park

    Full Text Available A three-dimensional (3D-printed customized bolus (3D bolus can be used for radiotherapy application to irregular surfaces. However, bolus fabrication based on computed tomography (CT scans is complicated and also delivers unwanted irradiation. Consequently, we fabricated a bolus using a 3D scanner and evaluated its efficacy. The head of an Alderson Rando phantom was scanned with a 3D scanner. The 3D surface data were exported and reconstructed with Geomagic Design X software. A 3D bolus of 5-mm thickness designed to fit onto the nose was printed with the use of rubber-like printing material, and a radiotherapy plan was developed. We successfully fabricated the customized 3D bolus, and further, a CT simulation indicated an acceptable fit of the 3D bolus to the nose. There was no air gap between the bolus and the phantom surface. The percent depth dose (PDD curve of the phantom with the 3D bolus showed an enhanced surface dose when compared with that of the phantom without the bolus. The PDD of the 3D bolus was comparable with that of a commercial superflab bolus. The radiotherapy plan considering the 3D bolus showed improved target coverage when compared with that without the bolus. Thus, we successfully fabricated a customized 3D bolus for an irregular surface using a 3D scanner instead of a CT scanner.

  3. Single-Shot, Volumetrically Illuminated, Three-Dimensional, Tomographic Laser-Induced-Fluorescence Imaging in a Gaseous Free Jet

    Science.gov (United States)

    2016-04-28

    Single- shot , volumetrically illuminated, three- dimensional, tomographic laser-induced- fluorescence imaging in a gaseous free jet Benjamin R. Halls...37081 Göttingen, Germany 4School of Mechanical Engineering, Purdue University, West Lafayette, IN 47907, USA 5trmeyer@purdue.edu 6james.gord...us.af.mil Abstract: Single- shot , tomographic imaging of the three-dimensional concentration field is demonstrated in a turbulent gaseous free jet in co-flow

  4. Path Planning in Three Dimensional Environment Using Feedback Linearization (Preprint)

    National Research Council Canada - National Science Library

    Schumacher, Corey J; Kanchanavally, Shreecharan; Ordonez, Raul

    2006-01-01

    This paper presents a control scheme via feedback linearization for three-dimensional cooperative path planning of a class of interconnected systems in general, and unmanned aerial vehicles (UAVs) in particular...

  5. 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.

  6. 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)

  7. Three dimensional QSAR: applications in pharmacology and toxicology

    National Research Council Canada - National Science Library

    Doucet, Jean-Pierre; Panaye, Annick

    2010-01-01

    ... networks and support vector machines. Three-Dimensional QSAR addresses the scope and limitations of different modeling techniques using case studies from pharmacology, toxicology, and ecotoxicology to demonstrate the utility of each...

  8. Three-dimensional anthropometry of the adult face.

    Science.gov (United States)

    1978-03-01

    This study describes a new three-dimensional anatomical axis system based on four conventional anthropometrical face landmarks. Coincident as a coordinate (orthogonal) axis system, this reference system was developed to provide convenient orientation...

  9. 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. © Wiley Periodicals, Inc.

  10. Utility of three-dimensional method for diagnosing meniscal lesions

    International Nuclear Information System (INIS)

    Ohshima, Suguru; Nomura, Kazutoshi; Hirano, Mako; Hashimoto, Noburo; Fukumoto, Tetsuya; Katahira, Kazuhiro

    1998-01-01

    MRI of the knee is a useful method for diagnosing meniscal tears. Although the spin echo method is usually used for diagnosing meniscal tears, we examined the utility of thin slice scan with the three-dimensional method. We reviewed 70 menisci in which arthroscopic findings were confirmed. In this series, sensitivity was 90.9% for medial meniscal injuries and 68.8% for lateral meniscal injuries. There were 3 meniscal tears in which we could not detect tears on preoperative MRI. We could find tears in two of these cases when re-evaluated using the same MRI. In conclusion, we can get the same diagnostic rate with the three-dimensional method compared with the spin echo method. Scan time of the three-dimensional method is 3 minutes, on the other hand that of spin echo method in 17 minutes. This slice scan with three-dimensional method is useful for screening meniscal injuries before arthroscopy. (author)

  11. Analysis and validation of carbohydrate three-dimensional structures

    International Nuclear Information System (INIS)

    Lütteke, Thomas

    2009-01-01

    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

  12. Analysis of three-dimensional transient seepage into ditch drains ...

    Indian Academy of Sciences (India)

    Ratan Sarmah

    dimensional solutions to the problem are actually valid not for a field of finite size but for an infinite one only. Keywords. Analytical models; three-dimensional ponded ditch drainage; transient seepage; variable ponding; hydraulic conductivity ...

  13. Fabrication of three-dimensional scaffolds using precision extrusion deposition with an assisted cooling device

    Energy Technology Data Exchange (ETDEWEB)

    Hamid, Q; Snyder, J; Wang, C; Guceri, S; Sun, W [Department of Mechanical Engineering and Mechanics, Drexel University, Philadelphia, PA (United States); Timmer, M; Hammer, J, E-mail: sunwei@drexel.edu [Advanced Technologies and Regenerative Medicine, Somerville, NJ (United States)

    2011-09-15

    In the field of biofabrication, tissue engineering and regenerative medicine, there are many methodologies to fabricate a building block (scaffold) which is unique to the target tissue or organ that facilitates cell growth, attachment, proliferation and/or differentiation. Currently, there are many techniques that fabricate three-dimensional scaffolds; however, there are advantages, limitations and specific tissue focuses of each fabrication technique. The focus of this initiative is to utilize an existing technique and expand the library of biomaterials which can be utilized to fabricate three-dimensional scaffolds rather than focusing on a new fabrication technique. An expanded library of biomaterials will enable the precision extrusion deposition (PED) device to construct three-dimensional scaffolds with enhanced biological, chemical and mechanical cues that will benefit tissue generation. Computer-aided motion and extrusion drive the PED to precisely fabricate micro-scaled scaffolds with biologically inspired, porosity, interconnectivity and internal and external architectures. The high printing resolution, precision and controllability of the PED allow for closer mimicry of tissues and organs. The PED expands its library of biopolymers by introducing an assisting cooling (AC) device which increases the working extrusion temperature from 120 to 250 deg. C. This paper investigates the PED with the integrated AC's capabilities to fabricate three-dimensional scaffolds that support cell growth, attachment and proliferation. Studies carried out in this paper utilized a biopolymer whose melting point is established to be 200 deg. C. This polymer was selected to illustrate the newly developed device's ability to fabricate three-dimensional scaffolds from a new library of biopolymers. Three-dimensional scaffolds fabricated with the integrated AC device should illustrate structural integrity and ability to support cell attachment and proliferation.

  14. Simulation on three dimensional bubble formation using MARS

    International Nuclear Information System (INIS)

    Kunugi, Tomoaki

    1997-01-01

    This paper describes a numerical simulation on three-dimensional bubble formation by means of the MARS (Multi-interfaces Advection and Reconstruction Solver) developed by the author. The comparison between two-dimensional and three-dimensional simulation on an agglomeration of two bubbles is discussed. Moreover, some simulation results regarding a phase change phenomena such as a boiling and condensation in a two dimensional enclosure with heated and cooled walls are presented. (author)

  15. Computational study of three-dimensional wake structure

    International Nuclear Information System (INIS)

    Himeno, R.; Shirayama, S.; Kamo, K.; Kuwahara, K.

    1986-01-01

    Three-dimensional wake structure is studied by numerically solving the incompressible Navier-Stokes equations. Results are visualized by a three-dimensional color graphic system. It was found that a pair of vortex tubes separated from a body plays the most important role in the wake. Near the body vortex tubes are rather stable, however, they gradually become unsteady as they flow down

  16. Alignment-free three-dimensional optical metamaterials.

    Science.gov (United States)

    Zhao, Yang; Shi, Jinwei; Sun, Liuyang; Li, Xiaoqin; Alù, Andrea

    2014-03-05

    Three-dimensional optical metamaterials based on multilayers typically rely on critical vertical alignment to achieve the desired functionality. Here the conditions under which three-dimensional metamaterials with different functionalities may be realized without constraints on alignment are analyzed and demonstrated experimentally. This study demonstrates that the release of alignment constraints for multilayered metamaterials is allowed, while their anomalous interaction with light is preserved. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Comparison of two three-dimensional cephalometric analysis computer software

    OpenAIRE

    Sawchuk, Dena; Alhadlaq, Adel; Alkhadra, Thamer; Carlyle, Terry D; Kusnoto, Budi; El-Bialy, Tarek

    2014-01-01

    Background: Three-dimensional cephalometric analyses are getting more attraction in orthodontics. The aim of this study was to compare two softwares to evaluate three-dimensional cephalometric analyses of orthodontic treatment outcomes. Materials and Methods: Twenty cone beam computed tomography images were obtained using i-CAT® imaging system from patient's records as part of their regular orthodontic records. The images were analyzed using InVivoDental5.0 (Anatomage Inc.) and 3DCeph™ (Unive...

  18. 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.

  19. Three-dimensional reconstruction of functional brain images

    International Nuclear Information System (INIS)

    Inoue, Masato; Shoji, Kazuhiko; Kojima, Hisayoshi; Hirano, Shigeru; Naito, Yasushi; Honjo, Iwao

    1999-01-01

    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

  20. Discretization model for nonlinear dynamic analysis of three dimensional structures

    International Nuclear Information System (INIS)

    Hayashi, Y.

    1982-12-01

    A discretization model for nonlinear dynamic analysis of three dimensional structures is presented. The discretization is achieved through a three dimensional spring-mass system and the dynamic response obtained by direct integration of the equations of motion using central diferences. First the viability of the model is verified through the analysis of homogeneous linear structures and then its performance in the analysis of structures subjected to impulsive or impact loads, taking into account both geometrical and physical nonlinearities is evaluated. (Author) [pt

  1. Three-dimensional stellarator equilibrium as an ohmic steady state

    International Nuclear Information System (INIS)

    Park, W.; Monticello, D.A.; Strauss, H.; Manickam, J.

    1985-07-01

    A stable three-dimensional stellarator equilibrium can be obtained numerically by a time-dependent relaxation method using small values of dissipation. The final state is an ohmic steady state which approaches an ohmic equilibrium in the limit of small dissipation coefficients. We describe a method to speed up the relaxation process and a method to implement the B vector . del p = 0 condition. These methods are applied to obtain three-dimensional heliac equilibria using the reduced heliac equations

  2. MATERIALS COMPATIBILITY STUDY FOR THREE-DIMENSIONAL PRINTER MATERIALS

    Science.gov (United States)

    2017-09-01

    MATERIALS COMPATIBILITY STUDY FOR THREE-DIMENSIONAL PRINTER MATERIALS ECBC-TR-1459 James D. Wright Jr. Mary...REPORT DATE (DD-MM-YYYY) XX-09-2017 2. REPORT TYPE Final 3. DATES COVERED (From - To) Mar 2016 – Dec 2016 4. TITLE AND SUBTITLE Materials ...Compatibility Study for Three-Dimensional Printer Materials 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Wright

  3. Some Remarks on the Three Dimensionality of Hydrofoil Cavitation

    Directory of Open Access Journals (Sweden)

    Mehmet Salih KARAALİOĞLU

    2017-12-01

    Full Text Available As it is well-known that cavitation is a very important physical phenomenon that affects significantly the performance of three-dimensional hydrofoils. Prediction of cavitation on three-dimensional hydrofoils is very important in the design stage. In this study, some approaches have been verified for hydrofoil cavitation. The main aim of this paper is to compare the mid-section pressure distribution of three-dimensional cavitating rectangular hydrofoil for increasing aspect ratios, with the pressure distribution of two-dimensional cavitating hydrofoil having the same section geometry as in the three-dimensional hydrofoil. In this study, a boundary element (panel method (BEM has been applied to investigate the hydrofoil cavitation for both two- and three-dimensional cases. Two-dimensional analytical solution in case of cavitating flat-plate has also been applied for comparison. It has been shown that the pressure distributions on the mid-section of three-dimensional cavitating and non-cavitating hydrofoil for increasing aspect ratios have converged to the solutions in two-dimensional case.

  4. Ordered three-dimensional interconnected nanoarchitectures in anodic porous alumina

    Science.gov (United States)

    Martín, Jaime; Martín-González, Marisol; Fernández, Jose Francisco; Caballero-Calero, Olga

    2014-01-01

    Three-dimensional nanostructures combine properties of nanoscale materials with the advantages of being macro-sized pieces when the time comes to manipulate, measure their properties, or make a device. However, the amount of compounds with the ability to self-organize in ordered three-dimensional nanostructures is limited. Therefore, template-based fabrication strategies become the key approach towards three-dimensional nanostructures. Here we report the simple fabrication of a template based on anodic aluminum oxide, having a well-defined, ordered, tunable, homogeneous 3D nanotubular network in the sub 100 nm range. The three-dimensional templates are then employed to achieve three-dimensional, ordered nanowire-networks in Bi2Te3 and polystyrene. Lastly, we demonstrate the photonic crystal behavior of both the template and the polystyrene three-dimensional nanostructure. Our approach may establish the foundations for future high-throughput, cheap, photonic materials and devices made of simple commodity plastics, metals, and semiconductors. PMID:25342247

  5. Development Report on the Idaho National Laboratory Sitewide Three-Dimensional Aquifer Model

    Energy Technology Data Exchange (ETDEWEB)

    Thomas R. Wood; Catherine M. Helm-Clark; Hai Huang; Swen Magnuson; Travis McLing; Brennon Orr; Michael J. Rohe; Mitchell A. Plummer; Robert Podgorney; Erik Whitmore; Michael S. Roddy

    2007-09-01

    A sub-regional scale, three-dimensional flow model of the Snake River Plain Aquifer was developed to support remediation decisions for Waste Area Group 10, Operable Unit 10 08 at the Idaho National Laboratory (INL) Site. This model has been calibrated primarily to water levels and secondarily to groundwater velocities interpreted from stable isotope disequilibrium studies and the movement of anthropogenic contaminants in the aquifer from facilities at the INL. The three-dimensional flow model described in this report is one step in the process of constructing a fully three-dimensional groundwater flow and contaminant transport model as prescribed in the Idaho National Engineering and Environmental Laboratory Operable Unit 10-08 Sitewide Groundwater Model Work Plan. An updated three-dimensional hydrogeologic conceptual model is presented along with the geologic basis for the conceptual model. Sediment-dominated three-dimensional volumes were used to represent the geology and constrain groundwater flow as part of the conceptual model. Hydrological, geochemical, and geological data were summarized and evaluated to infer aquifer behavior. A primary observation from development and evaluation of the conceptual model was that relative to flow on a regional scale, the aquifer can be treated with steady-state conditions. Boundary conditions developed for the three-dimensional flow model are presented along with inverse simulations that estimate parameterization of hydraulic conductivity. Inverse simulations were performed using the pilot-point method to estimate permeability distributions. Thermal modeling at the regional aquifer scale and at the sub-regional scale using the inverted permeabilities is presented to corroborate the results of the flow model. The results from the flow model show good agreement with simulated and observed water levels almost always within 1 meter. Simulated velocities show generally good agreement with some discrepancies in an interpreted low

  6. Visual Interpretation with Three-Dimensional Annotations (VITA): Three-Dimensional Image Interpretation Tool for Radiological Reporting

    OpenAIRE

    Roy, Sharmili; Brown, Michael S.; Shih, George L.

    2013-01-01

    This paper introduces a software framework called Visual Interpretation with Three-Dimensional Annotations (VITA) that is able to automatically generate three-dimensional (3D) visual summaries based on radiological annotations made during routine exam reporting. VITA summaries are in the form of rotating 3D volumes where radiological annotations are highlighted to place important clinical observations into a 3D context. The rendered volume is produced as a Digital Imaging and Communications i...

  7. Electron tomography, three-dimensional Fourier analysis and colour prediction of a three-dimensional amorphous biophotonic nanostructure

    Science.gov (United States)

    Shawkey, Matthew D.; Saranathan, Vinodkumar; Pálsdóttir, Hildur; Crum, John; Ellisman, Mark H.; Auer, Manfred; Prum, Richard O.

    2009-01-01

    Organismal colour can be created by selective absorption of light by pigments or light scattering by photonic nanostructures. Photonic nanostructures may vary in refractive index over one, two or three dimensions and may be periodic over large spatial scales or amorphous with short-range order. Theoretical optical analysis of three-dimensional amorphous nanostructures has been challenging because these structures are difficult to describe accurately from conventional two-dimensional electron microscopy alone. Intermediate voltage electron microscopy (IVEM) with tomographic reconstruction adds three-dimensional data by using a high-power electron beam to penetrate and image sections of material sufficiently thick to contain a significant portion of the structure. Here, we use IVEM tomography to characterize a non-iridescent, three-dimensional biophotonic nanostructure: the spongy medullary layer from eastern bluebird Sialia sialis feather barbs. Tomography and three-dimensional Fourier analysis reveal that it is an amorphous, interconnected bicontinuous matrix that is appropriately ordered at local spatial scales in all three dimensions to coherently scatter light. The predicted reflectance spectra from the three-dimensional Fourier analysis are more precise than those predicted by previous two-dimensional Fourier analysis of transmission electron microscopy sections. These results highlight the usefulness, and obstacles, of tomography in the description and analysis of three-dimensional photonic structures. PMID:19158016

  8. Three-dimensional surface anthropometry: Applications to the human body

    Science.gov (United States)

    Jones, Peter R. M.; Rioux, Marc

    1997-09-01

    Anthropometry is the study of the measurement of the human body. By tradition this has been carried out taking the measurements from body surface landmarks, such as circumferences and breadths, using simple instruments like tape measures and calipers. Three-dimensional (3D) surface anthropometry enables us to extend the study to 3D geometry and morphology of mainly external human body tissues. It includes the acquisition, indexing, transmission, archiving, retrieval, interrogation and analysis of body size, shape, and surface together with their variability throughout growth and development to adulthood. While 3D surface anthropometry surveying is relatively new, anthropometric surveying using traditional tools, such as calipers and tape measures, is not. Recorded studies of the human form date back to ancient times. Since at least the 17th century 1 investigators have made attempts to measure the human body for physical properties such as weight, size, and centre of mass. Martin documented 'standard' body measurement methods in a handbook in 1928. 2 This paper reviews the past and current literature devoted to the applications of 3D anthropometry because true 3D scanning of the complete human body is fast becoming a reality. We attempt to take readers through different forms of technology which deal with simple forms of projected light to the more complex advanced forms of laser and video technology giving low and/or high resolution 3D data. Information is also given about image capture of size and shape of the whole as well as most component parts of the human body. In particular, the review describes with explanations a multitude of applications, for example, medical, product design, human engineering, anthropometry and ergonomics etc.

  9. THREE-DIMENSIONAL SIMULATION OF FLOW AT AN OPEN-CHANNEL CONFLUENCE WITH TURBULENCE MODELS

    Science.gov (United States)

    Dinh Thanh, Mung; Kimura, Ichiro; Shimizu, Yasuyuki

    Open-channel confluence flows are common in natural river systems as well as in environmental and hydraulic engineering, such as in river engineering. Often, these flows are three-dimensional and complex,while numerical studies fully describing confluence flow are still few. This paper presents the results of investigation of confluence flow using a three-dimensional numerical model with the linear and nonlinear k-ε models. To treat the dynamic boundary condition at the free surface, non-hydrostatic pressure is included in the present model. The model is validated using the experimental data available. Adequacy of the present model with two turbulence models above is indicated based on the result analysis. The nonlinear model is indicated as the more advantageous one than the linear one.

  10. Conformal Field Theories on K3 and Three-Dimensional Gauge Theories

    CERN Document Server

    Mayr, Peter

    2000-01-01

    According to a recent conjecture, the moduli space of the heterotic conformal field theory on a $G\\subset$ ADE singularity of an ALE space is equivalent to the moduli space of a pure $\\cx N=4$ supersymmetric three-dimensional gauge theory with gauge group G. We establish this relation using geometric engineering of heterotic strings and generalize it to theories with non-trivial matter content.

  11. 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 r....... The overall presentation is supported by numerical simulations of electrode misalignment caused by the flexibility of the welding machine arms and electrical shunting due to consecutive welds in the resistance spot welding of two sheets.......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...

  12. Robot vision based on three-dimensional model

    International Nuclear Information System (INIS)

    Shirai, Yoshiaki

    1985-01-01

    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.)

  13. Three-dimensional magnetospheric equilibrium with isotropic pressure

    International Nuclear Information System (INIS)

    Cheng, C.Z.

    1995-05-01

    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

  14. Three-Dimensional (3D) Additive Construction: Printing with Regolith

    Science.gov (United States)

    Tsoras, Alexandra

    2013-01-01

    Three dimensional (3D) printing is a new and booming topic in many realms of research and engineering technology. When it comes to space science and aerospace engineering, it can be useful in numerous ways. As humans travel deeper into space and farther from Earth, sending large quantities of needed supplies from Earth for a mission becomes astronomically expensive and less plausible. In order to reach further to new places, In Situ Resource Utilization (ISRU), a project that pushes for technologies to use materials already present in the destination's environment, is necessary. By using materials already available in space such as regolith from the Moon, Mars, or an asteroid's surface, fewer materials need to be brought into space on a launched vehicle. This allows a vehicle to be filled with more necessary supplies for a deep space mission that may not be found in space, like food and fuel. This project's main objective was to develop a 3D printer that uses regolith to "print" large structures, such as a dome, to be used as a heat shield upon a vehicle's reentry into the atmosphere or even a habitat. 3D printing is a growing technology that uses many different methods to mix, heat, and mold a material into a specific shape. In order to heat the regolith enough to stick together into a solid shape, it must be sintered at each layer of material that is laid. Sintering is a process that heats and compresses a powdered material until it fuses into a solid, which requires a lot of energy input. As an alternative, a polymer can be mixed with the regolith before or as it is sent to the 3D printer head to be placed in the specific shape. The addition of the polymer, which melts and binds at much lower temperatures than sintering temperatures, greatly decreases the required heating temperature and energy input. The main task of the project was to identify a functional material for the printer. The first step was to find a miscible. polymer/solvent solution. This solution

  15. Three-dimensional imaging of rheumatoid hands with MR

    International Nuclear Information System (INIS)

    Phillips, J.J.; Fischer, H.; Hollister, A.; Myers, L.

    1990-01-01

    Quantitative evaluation of soft-tissue proliferation associated with rheumatoid disease provided an objective measure of the activity and pattern of joint pathology. This paper propose a three-dimensional model for this purpose. With use of a 1.5-T Picker MR imager and a stellar GS 2000 computer graphics workstation, hands from patients with rheumatoid arthritis and age-matched controls were imaged to measure the quantity and location of inflammatory tissues. Three-dimensional Fourier transform gradient-echo sequences were used, with 0.8-1.6-mm section thickness. The definition of soft-tissue abnormalities and normal structures was facilitated by image smoothing and edge-detection computer algorithms. Separation of joint components permitted volume measurements and three-dimensional graphic displays

  16. On three-dimensional quiver gauge theories of type B

    Science.gov (United States)

    Dey, Anindya; Hanany, Amihay; Koroteev, Peter; Mekareeya, Noppadol

    2017-09-01

    We study three-dimensional supersymmetric quiver gauge theories with a nonsimply laced global symmetry primarily focusing on framed affine B N quiver theories. Using a supersymmetric partition function on a three sphere, and its transformation under S-duality, we study the three-dimensional ADHM quiver for SO(2 N + 1) instantons with a half-integer Chern-Simons coupling. The theory after S-duality has no Lagrangian, and can not be represented by a single quiver, however its partition function can be conveniently described by a collection of framed affine B N quivers. This correspondence can be conjectured to generalize three-dimensional mirror symmetry to theories with nontrivial Chern-Simons terms. In addition, we propose a formula for the superconformal index of a theory described by a framed affine B N quiver.

  17. Three-dimensional particle image velocimetry measurement technique

    International Nuclear Information System (INIS)

    Hassan, Y.A.; Seeley, C.H.; Henderson, J.A.; Schmidl, W.D.

    2004-01-01

    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)

  18. Eustachian tube three-dimensional reconstruction of secretory otitis media

    International Nuclear Information System (INIS)

    Yu Yafeng; Zhou Weirong; Bao Xueping; Li Min; Hu Zhenmin

    2006-01-01

    Objective: To study relationship between Eustachian tube and secretory otitis media and to explore the pathogeny of secretory otitis by three-dimensional reconstruction of Eustachian tube. Methods: Thirty cases of secretory otitis media (male 19, female 11) were selected randomly. Everyone was checked by otoscope and audiometry. Their bilateral Eustachian tubes were scanning by helix CT while making Valsalva's action. All images were passed on to work station to make three-dimensional reconstruction. Results: Four patients were found have Eustachian tube diseases, while most of patients' Eustachian tubes ventilated normally. Conclusions: Three-dimensional reconstruction of Eustachian tube can open out some pathogens of some secretory otitis medias. It will be helpful to diagnosis and therapy of secretory otitis media. (authors)

  19. 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.

  20. Three-dimensional, three-component wall-PIV

    Science.gov (United States)

    Berthe, André; Kondermann, Daniel; Christensen, Carolyn; Goubergrits, Leonid; Garbe, Christoph; Affeld, Klaus; Kertzscher, Ulrich

    2010-06-01

    This paper describes a new time-resolved three-dimensional, three-component (3D-3C) measurement technique called wall-PIV. It was developed to assess near wall flow fields and shear rates near non-planar surfaces. The method is based on light absorption according to Beer-Lambert’s law. The fluid containing a molecular dye and seeded with buoyant particles is illuminated by a monochromatic, diffuse light. Due to the dye, the depth of view is limited to the near wall layer. The three-dimensional particle positions can be reconstructed by the intensities of the particle’s projection on an image sensor. The flow estimation is performed by a new algorithm, based on learned particle trajectories. Possible sources of measurement errors related to the wall-PIV technique are analyzed. The accuracy analysis was based on single particle experiments and a three-dimensional artificial data set simulating a rotating sphere.

  1. Shape memory polymers: three-dimensional isotropic modeling

    Science.gov (United States)

    Balogun, Olaniyi; Mo, Changki

    2014-04-01

    This paper presents a comprehensive three-dimensional isotropic numerical simulation for a thermo-mechanical constitutive model of shape memory polymers (SMPs). In order to predict the thermo-mechanical behavior of SMPs, a one-dimensional rheological thermo-mechanical constitutive model is adopted, translated into a three-dimensional form and a time discrete form of the three-dimensional model is then presented. Numerical simulation of this model was developed using the UMAT subroutine capabilities of the finite element software ABAQUS. Evolution of the analysis was conducted by making use of the backward difference scheme, which was applied to all quantities within the model, including the material properties. A comparison of the numerical simulation results was carried out with the available experimental data. Numerical simulation results clearly exhibit the thermo-mechanical properties of the material which include shape fixity, shape recovery, and recovery stress. Finally, a prediction for the transverse and shear directions of the material is presented.

  2. Novel multipole Wien filter as three-dimensional spin manipulator

    Science.gov (United States)

    Yasue, T.; Suzuki, M.; Tsuno, K.; Goto, S.; Arai, Y.; Koshikawa, T.

    2014-04-01

    Spin polarized electron beam is often used in material characterizations which relates to magnetism as well as in the high energy particle physics. The manipulation of the spin polarization toward the arbitrary direction is indispensable in such studies. In the present work, a novel multipole Wien filter is proposed as the three-dimensional spin manipulator, and a prototype 8-pole Wien filter is developed. It is applied to spin polarized low energy electron microscopy, and the variation of the magnetic contrast with managing the spin polarization is evaluated. It is confirmed that the novel multipole Wien filter can manipulate the spin polarization three-dimensionally.

  3. Novel multipole Wien filter as three-dimensional spin manipulator

    Energy Technology Data Exchange (ETDEWEB)

    Yasue, T., E-mail: yasue@isc.osakac.ac.jp; Suzuki, M.; Koshikawa, T. [Fundamental Electronics Research Institute, Osaka Electro-Communication University, 18-8 Hatsu-cho, Neyagawa, Osaka 572-8530 (Japan); Tsuno, K. [Electron Optics Solutions Tsuno, 10-11 Mihori, Akishima, Tokyo 196-0001 (Japan); Goto, S. [Sanyu Electron Co., Ltd., 1-22-6 Hyakunin-cho, Shinjyuku, Tokyo 169-0073 (Japan); Arai, Y. [Terabase Inc., Myodaiji, Okazaki, Aichi 444-8787 (Japan)

    2014-04-15

    Spin polarized electron beam is often used in material characterizations which relates to magnetism as well as in the high energy particle physics. The manipulation of the spin polarization toward the arbitrary direction is indispensable in such studies. In the present work, a novel multipole Wien filter is proposed as the three-dimensional spin manipulator, and a prototype 8-pole Wien filter is developed. It is applied to spin polarized low energy electron microscopy, and the variation of the magnetic contrast with managing the spin polarization is evaluated. It is confirmed that the novel multipole Wien filter can manipulate the spin polarization three-dimensionally.

  4. Three Dimensional Analysis of Elastic Rocket and Launcher at Launching

    Science.gov (United States)

    Takeuchi, Shinsuke

    In this paper, a three-dimensional analysis of launching dynamics of a sounding rocket is investigated. In the analysis, the elastic vibration of the vehicle and launcher is considered. To estimate a trajectory dispersion including the effect of elasticity of the vehicle and launcher, a three-dimensional numerical simulation of a launch is performed. The accuracy of the numerical simulation is discussed and it is concluded that the simulation can estimate the maximum value of the trajectory dispersion properly. After that, the maximum value is estimated for the actual sounding rocket and the value is shown to be within the safty margin for this particular case.

  5. 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.

  6. Weyl and Dirac semimetals in three-dimensional solids

    Science.gov (United States)

    Armitage, N. P.; Mele, E. J.; Vishwanath, Ashvin

    2018-01-01

    Weyl and Dirac semimetals are three-dimensional phases of matter with gapless electronic excitations that are protected by topology and symmetry. As three-dimensional analogs of graphene, they have generated much recent interest. Deep connections exist with particle physics models of relativistic chiral fermions, and, despite their gaplessness, to solid-state topological and Chern insulators. Their characteristic electronic properties lead to protected surface states and novel responses to applied electric and magnetic fields. The theoretical foundations of these phases, their proposed realizations in solid-state systems, and recent experiments on candidate materials as well as their relation to other states of matter are reviewed.

  7. Three-dimensional Reciprocal Structures: Morphology, Concepts, Generative Rules

    DEFF Research Database (Denmark)

    Parigi, Dario; Pugnale, Alberto

    2012-01-01

    This paper present seven different three dimensional structures based on the principle of structural reciprocity with superimposition joint and standardized un-notched elements. Such typology could be regarded as being intrinsically three-dimensional because elements sit one of the top of the oth......, causing every configuration to develop naturally out-of the plane. The structures presented here were developed and built by the students of the Master of Science in “Architectural Design” during a two week long workshop organized at Aalborg University in the fall semester 2011....

  8. Data Visualization in Physics II: VRML and Java for three-dimensional imaging and fully three-dimensional movies

    Science.gov (United States)

    Fenton, Flavio H.; Evans, Steven J.; Hastings, Harold M.; Cherry, Elizabeth M.

    2006-03-01

    Presentation and analysis of large three-dimensional data sets is in general hard to do using only two-dimensional figures and plots. In this talk, we will demonstrate techniques for illustrating static and dynamic three-dimensional objects and data using Virtual Reality Modeling Language (VRML) as well as Java. The advantage of these two languages is that they are platform-independent, which allows for easy sharing of data and visualizations. In addition, manipulation of data is relatively easy as rotation, translation and zooming can be done in real- time for static objects as well as for data and objects that vary and deform in time. Examples of fully three-dimensional movies will be shown, including dendritic growth and propagation of electrical waves in cardiac tissue. In addition, we will show how to include VRML and Java viewers in PowerPoint for easy presentation of results in classes and seminars.

  9. Acid-base properties of complexes with three-dimensional polyligands. Complexes with three-dimensional polyphosphoric acids

    International Nuclear Information System (INIS)

    Kopylova, V.D.; Bojko, Eh.T.; Saldadze, K.M.

    1985-01-01

    By the method of potentiometric titration acid-base properties of uranyl (2) complexes with three-dimensional polyphosphoric acids, KRF-8p, KF-1, KF-7 prepared by phosphorylation of copolymer of styrene and divinylbenzene or saponification of the copolymers of di-2,2'-chloroethyl ester of vinylphosphonic acid with divinyl benzene are studied. It is shown that in case of formation in the phase of three-dimensional polyphosphoric acids of UO 2 2+ complexes with the growth of bond covalence of metal ion-phosphonic group the acidjty of the second hydroxyl of the phosphonic group increases

  10. Signal processing of eddy current three-dimensional maps

    International Nuclear Information System (INIS)

    Birac, C.; David, D.; Lamant, D.

    1987-01-01

    Digital processing of eddy current three-dimensional maps improves accuracy of detection: flattening, filtering, computing deconvolution, mapping new variables,.., give new possibilities for difficult test problems. With simulation of defects, probes, probe travels, it is now possible to compute new eddy current processes, without machining defects or building probes

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

    DEFF Research Database (Denmark)

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

    2002-01-01

    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 swirl...

  12. Two-and three-dimensional gravity modeling along western ...

    Indian Academy of Sciences (India)

    The western continental margin and the intraplate Narmada-Tapti rifts are primarily covered by Deccan flood basalts. Three-dimensional gravity modeling of +70 mgal Bouguer gravity highs extending in the north-south direction along the western continental margin rift indicates the presence of a subsurface high density, ...

  13. Kondo effect in three-dimensional Dirac and Weyl systems

    NARCIS (Netherlands)

    Mitchell, Andrew K.; Fritz, Lars

    2015-01-01

    Magnetic impurities in three-dimensional Dirac and Weyl systems are shown to exhibit a fascinatingly diverse range of Kondo physics, with distinctive experimental spectroscopic signatures. When the Fermi level is precisely at the Dirac point, Dirac semimetals are in fact unlikely candidates for a

  14. Rigid isotopy classification of real three-dimensional cubics

    Energy Technology Data Exchange (ETDEWEB)

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

    2006-08-31

    We prove that the space of non-singular real three-dimensional cubics has precisely nine connected components. We also study the space of real canonical curves of genus 4 and prove, in particular, that it consists of eight connected components.

  15. Monitoring the three-dimensional ionospheric electron density ...

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Earth System Science; Volume 116; Issue 3. Monitoring the three-dimensional ionospheric ... A numerical experiment is used to validate the reliability of the method and its advantages to the classical algebraic reconstruction technique (ART). This is then used to reconstruct the IED images using ...

  16. 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…

  17. Freehand three-dimensional ultrasound to assess semitendinosus muscle morphology

    NARCIS (Netherlands)

    Haberfehlner, H.; Maas, H.; Harlaar, J.; Becher, J.G.; Buizer, A.I.; Jaspers, R.T.

    2016-01-01

    In several neurological disorders and muscle injuries, morphological changes of the m. semitendinosus (ST) are presumed to contribute to movement limitations around the knee. Freehand three-dimensional (3D) ultrasound (US), using position tracking of two-dimensional US images to reconstruct a 3D

  18. 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.

  19. Three-dimensional reconstruction of the pigeon inner ear

    NARCIS (Netherlands)

    Hofman, R.; Segenhout, J. M.; Wit, H. P.

    2009-01-01

    Three-dimensional reconstructions of the inner ear of the pigeon (Columba livia domestica), from two-dimensional images, obtained with (conventional) light microscopy or orthogonal-plane fluorescence optical sectioning (OPFOS), are presented. The results are compared with available information on

  20. Three-dimensional structure of heat shock protein 90 from ...

    Indian Academy of Sciences (India)

    Madhu Sudhan

    2007-04-02

    Apr 2, 2007 ... Using inhibitors specific to the nucleotide binding domain of Hsp90, we have shown potent growth inhibitory ... role played by PfHsp90 in parasite growth, we have modeled its three dimensional structure using recently described full length .... PfHsp90 and for the development of small-molecule targets.

  1. 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...

  2. Three dimensional reconstruction of tomographic images of the retina

    International Nuclear Information System (INIS)

    Glittenberg, C.; Zeiler, F.; Falkner, C.; Binder, S.; Povazay, B.; Hermann, B.; Drexler, W.

    2007-01-01

    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) [de

  3. hp Spectral element methods for three dimensional elliptic problems ...

    Indian Academy of Sciences (India)

    125, No. 3, August 2015, pp. 413–447. c Indian Academy of Sciences h-p Spectral element methods for three dimensional elliptic problems on non-smooth domains, Part-II: Proof of stability theorem. P DUTT1, AKHLAQ HUSAIN2,∗, A S VASUDEVA MURTHY3 and C S UPADHYAY4. 1Department of Mathematics & Statistics ...

  4. Three-dimensional echocardiographic assessment of the repaired mitral valve.

    Science.gov (United States)

    Maslow, Andrew; Mahmood, Feroze; Poppas, Athena; Singh, Arun

    2014-02-01

    This study examined the geometric changes of the mitral valve (MV) after repair using conventional and three-dimensional echocardiography. Prospective evaluation of consecutive patients undergoing mitral valve repair. Tertiary care university hospital. Fifty consecutive patients scheduled for elective repair of the mitral valve for regurgitant disease. Intraoperative transesophageal echocardiography. Assessments of valve area (MVA) were performed using two-dimensional planimetry (2D-Plan), pressure half-time (PHT), and three-dimensional planimetry (3D-Plan). In addition, the direction of ventricular inflow was assessed from the three-dimensional imaging. Good correlations (r = 0.83) and agreement (-0.08 +/- 0.43 cm(2)) were seen between the MVA measured with 3D-Plan and PHT, and were better than either compared to 2D-Plan. MVAs were smaller after repair of functional disease repaired with an annuloplasty ring. After repair, ventricular inflow was directed toward the lateral ventricular wall. Subgroup analysis showed that the change in inflow angle was not different after repair of functional disease (168 to 171 degrees) as compared to those presenting with degenerative disease (168 to 148 degrees; p<0.0001). Three-dimensional imaging provides caregivers with a unique ability to assess changes in valve function after mitral valve repair. Copyright © 2014 Elsevier Inc. All rights reserved.

  5. Mathematical modeling of three-dimensional images in emission tomography

    International Nuclear Information System (INIS)

    Koblik, Yu.N.; Khugaev, A. V.; Mktchyan, G.A.; Ioannou, P.; Dimovasili, E.

    2002-01-01

    The model of processing results of three-dimensional measurements in positron-emissive tomograph is proposed in this work. The algorithm of construction and visualization of phantom objects of arbitrary shape was developed and its concrete realization in view of program packet for PC was carried out

  6. Analysis of three-dimensional transient seepage into ditch drains ...

    Indian Academy of Sciences (India)

    Ratan Sarmah

    Abstract. An analytical solution in the form of infinite series is developed for predicting time-dependent three-dimensional seepage into ditch drains from a flat, homogeneous and anisotropic ponded field of finite size, the field being assumed to be surrounded on all its vertical faces by ditch drains with unequal water level ...

  7. Singularities at rims in three-dimensional fluid flow

    NARCIS (Netherlands)

    Driesen, C.H.; Kuerten, Johannes G.M.

    1999-01-01

    Asymptotic solutions are presented for Stokes flow near circular rims in three-dimensional geometries. Using nonstandard toroidal coordinates, asymptotic analytical expressions are derived for different corner angles. In comparison to the two-dimensional case, an extra critical corner angle value is

  8. and three-dimensional gravity modeling along western continental ...

    Indian Academy of Sciences (India)

    Three-dimensional gravity modeling of +70 mgal Bouguer gravity highs extending in the north-south direction along the western continental margin rift indicates the presence of a subsurface high density, mafic-ultramafic type, elongated, roughly ellipsoidal body. It is approximately 12.0 ± 1.2 km thick with its upper surface at ...

  9. Wave packet construction in three-dimensional quantum billiards ...

    Indian Academy of Sciences (India)

    Home; Journals; Pramana – Journal of Physics; Volume 86; Issue 1. Wave packet construction in three-dimensional quantum billiards: Visualizing the closed orbit, collapse and revival of wave packets in the cubical billiard. Maninder Kaur Bindiya Arora Mahmood Mian. Volume 86 Issue 1 January 2016 pp 31-48 ...

  10. Three-dimensional simulation of laser–plasma-based electron ...

    Indian Academy of Sciences (India)

    Abstract. A sequential three-dimensional (3D) particle-in-cell simulation code PICPSI-3D with a user friendly graphical user interface (GUI) has been developed and used to study the interaction of plasma with ultrahigh intensity laser radiation. A case study of laser–plasma-based electron acceleration has been carried out ...

  11. 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...

  12. Three-dimensional group manifold reductions of gravity

    Science.gov (United States)

    Linares, Román

    2005-04-01

    We review the three-dimensional group manifold reductions of pure Einstein gravity and we exhibit a new consistent group manifold reduction of gravity when the compactification group manifold is S3. The new reduction leads to a lower dimensional theory whose gauge group is SU(2).

  13. Robust cylinder fitting in three-dimensional point cloud data

    NARCIS (Netherlands)

    Nurunnabi, Abdul; Sadahiro, Yukio; Lindenbergh, R.C.

    2017-01-01

    This paper investigates the problems of cylinder fitting in laser scanning three-dimensional Point Cloud Data (PCD). Most existing methods require full cylinder data, do not study the presence of outliers, and are not statistically robust. But especially mobile laser scanning often has incomplete

  14. The Importance of Three-Dimensionality in Children's Art

    Science.gov (United States)

    Heldmeyer, Karen

    1978-01-01

    Investigated young children's ability to represent three-dimensionality in their drawings. Preschool, kindergarten and first grade children and adults were asked to draw a cube, a house, and a ball presented in a plain form, a form differentially decorated on each side, and in both 2- and 3-dimensional forms. (JMB)

  15. 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…

  16. Three dimensional simulated modelling of diffusion capacitance of ...

    African Journals Online (AJOL)

    A three dimensional (3-D) simulated modelling was developed to analyse the excess minority carrier density in the base of a polycrystalline bifacial silicon solar cell. The concept of junction recombination velocity was ado-pted to quantify carrier flow through the junction, and to examine the solar cell diffusion capacitance for ...

  17. Three-Dimensional Utah: 100 Years of Sculpture

    OpenAIRE

    Nora Eccles Harrison Museum of Art

    1996-01-01

    Three-Dimensional Utah: 100 Years of Sculpture began as a series of conversations about sculptors and sculpture nearly six years ago. Specific development of the exhibition began three years ago during the process of creating a national inventory of outdoor sculpture for a program called Save Outdoor Sculpture (SOS)! Utah is home to more than 200 pieces of outdoor sculpture.

  18. Three-dimensional computer models of electrospinning systems

    Directory of Open Access Journals (Sweden)

    Smółka Krzysztof

    2017-12-01

    Full Text Available Electrospinning is a very interesting method that allows the fabrication of continuous fibers with diameters down to a few nanometers. This paper presents an overview of electrospinning systems as well as their comparison using proposed three-dimensional parameterized numerical models. The presented solutions allow an analysis of the electric field distribution.

  19. Molecular dynamics study of two- and three-dimensional classical ...

    Indian Academy of Sciences (India)

    Abstract. We have carried out a molecular dynamics simulation of two- and three- dimensional double Yukawa fluids near the triple point. We have compared some of the static and dynamic correlation functions with those of Lennard–Jones, when parameters occurring in double Yukawa potential are chosen to fit ...

  20. 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...

  1. and three-dimensional models for analysis of optical absorption

    Indian Academy of Sciences (India)

    Unknown

    Goldberg et al 1975; Kam and Parkinson 1982; Baglio et al 1982, 1983; Oritz 1995; Li et al 1996) has been carried out on WS2, there is no detailed analysis of the absorption spectra obtained from the single crystals of WS2 on the basis of two- and three-dimensional models. We have therefore carried out this study and the.

  2. Optical and thermal performance of a three-dimensional compound ...

    Indian Academy of Sciences (India)

    The three-dimensional compound parabolic concentrator (3D CPC) was found to be more efficient than 2D CPC because of the higher concentration ratio. In the present work a 3D CPC was fabricated with a half acceptance angle of 4° for a spherical absorber of radius 100 mm. UV stabilized aluminized polyester foil having ...

  3. Wave packet construction in three-dimensional quantum billiards ...

    Indian Academy of Sciences (India)

    Keywords. Three-dimensional bound systems; revivals and collapses; quantum mechanics. PACS Nos 03.65.Ge; 03.65.Yz; 42.50.Md. 1. Introduction. The study of time evolution of the unbound and bound-state wave packet illuminates many features of the wave mechanics. These include both semiclassical features as well.

  4. KP Equation in a Three-Dimensional Unmagnetized Warm Dusty ...

    Indian Academy of Sciences (India)

    Kh. H. El-Shorbagy

    yahoo.com. MS received 24 May 2017; accepted 26 September 2017; published online 27 November 2017. Abstract. In this work, we investigate the propagation of three-dimensional nonlinear dust-acoustic and dust-. Coulomb waves in an ...

  5. Three-dimensional free vibration analysis of thick laminated circular ...

    African Journals Online (AJOL)

    Three-dimensional free vibration analysis of thick laminated circular plates. Sumit Khare, N.D. Mittal. Abstract. In this communication, a numerical analysis regarding free vibration of thick laminated circular plates, having free, clamped as well as simply-supported boundary conditions at outer edges of plates is presented.

  6. and three-dimensional gravity modeling along western continental ...

    Indian Academy of Sciences (India)

    R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22

    western continental margin and the intraplate Narmada-Tapti rifts suggests that the migration and concentration of high density magma in the upper lithosphere was much more dominant along the western continental margin rift. Based on the three-dimensional gravity modeling, it is conjectured that the emplacement of ...

  7. Three dimensional rigorous model for optical scattering problems

    NARCIS (Netherlands)

    Wei, X.

    2006-01-01

    We present a three-dimensional model based on the finite element method for solving the time-harmonic Maxwell equation in optics. It applies to isotropic or anisotropic dielectrics and metals, and to many configurations such as an isolated scatterer in a multilayer, bi-gratings and crystals. We

  8. Stability analysis of non-axisymmetric three-dimensional finite ...

    Indian Academy of Sciences (India)

    In three-dimensional formulation one prefers a spinning frame for derivation of the govern- ing equations (Nandi & Neogy 2001). In this spinning frame, the orthotropic bearing stiffness becomes periodic. The governing equations thus become parametric in nature. A rotor cross- section is symmetric when the rotor has same ...

  9. Three-dimensional simulations of viscoelastic instability in polymeric filaments

    DEFF Research Database (Denmark)

    Rasmussen, Henrik Koblitz; Hassager, Ole

    1999-01-01

    The three-dimensional Langrangian integral method is used to simulate the elastic end-plate instability that occurs in the rapid extension of some polymeric filaments between parallel plates. It is demonstrated that the upper convected Maxwell model describes the essential features of the instabi...

  10. Three-dimensional computer models of electrospinning systems

    Science.gov (United States)

    Smółka, Krzysztof; Firych-Nowacka, Anna; Lefik, Marcin

    2017-12-01

    Electrospinning is a very interesting method that allows the fabrication of continuous fibers with diameters down to a few nanometers. This paper presents an overview of electrospinning systems as well as their comparison using proposed three-dimensional parameterized numerical models. The presented solutions allow an analysis of the electric field distribution.

  11. Three dimensional internal electromagnetic pulse calculated by particle source method

    International Nuclear Information System (INIS)

    Wang Yuzhi; Wang Taichun

    1986-01-01

    The numerical results of the primary electric current and the internal electromagnetic pulse were obtained by particle method in the rectanglar cavity. The results obtained from this method is compared with three dimensional Euler-method. It is shown that two methods are in good agreement if the conditions are the same

  12. Protein-Based Three-Dimensional Memories and Associative Processors

    Science.gov (United States)

    Birge, Robert

    2008-03-01

    The field of bioelectronics has benefited from the fact that nature has often solved problems of a similar nature to those which must be solved to create molecular electronic or photonic devices that operate with efficiency and reliability. Retinal proteins show great promise in bioelectronic devices because they operate with high efficiency (˜0.65%), high cyclicity (>10^7), operate over an extended wavelength range (360 -- 630 nm) and can convert light into changes in voltage, pH, absorption or refractive index. This talk will focus on a retinal protein called bacteriorhodopsin, the proton pump of the organism Halobacterium salinarum. Two memories based on this protein will be described. The first is an optical three-dimensional memory. This memory stores information using volume elements (voxels), and provides as much as a thousand-fold improvement in effective capacity over current technology. A unique branching reaction of a variant of bacteriorhodopsin is used to turn each protein into an optically addressed latched AND gate. Although three working prototypes have been developed, a number of cost/performance and architectural issues must be resolved prior to commercialization. The major issue is that the native protein provides a very inefficient branching reaction. Genetic engineering has improved performance by nearly 500-fold, but a further order of magnitude improvement is needed. Protein-based holographic associative memories will also be discussed. The human brain stores and retrieves information via association, and human intelligence is intimately connected to the nature and enormous capacity of this associative search and retrieval process. To a first order approximation, creativity can be viewed as the association of two seemingly disparate concepts to form a totally new construct. Thus, artificial intelligence requires large scale associative memories. Current computer hardware does not provide an optimal environment for creating artificial

  13. Three dimensional finite element methods: Their role in the design of DC accelerator systems

    Energy Technology Data Exchange (ETDEWEB)

    Podaru, Nicolae C.; Gottdang, A.; Mous, D. J. W. [High Voltage Engineering Europa B.V., P.O. Box 99, 3800 AB, Amersfoort (Netherlands)

    2013-04-19

    High Voltage Engineering has designed, built and tested a 2 MV dual irradiation system that will be applied for radiation damage studies and ion beam material modification. The system consists of two independent accelerators which support simultaneous proton and electron irradiation (energy range 100 keV - 2 MeV) of target sizes of up to 300 Multiplication-Sign 300 mm{sup 2}. Three dimensional finite element methods were used in the design of various parts of the system. The electrostatic solver was used to quantify essential parameters of the solid-state power supply generating the DC high voltage. The magnetostatic solver and ray tracing were used to optimize the electron/ion beam transport. Close agreement between design and measurements of the accelerator characteristics as well as beam performance indicate the usefulness of three dimensional finite element methods during accelerator system design.

  14. Transient Three-Dimensional Side Load Analysis of a Film Cooled Nozzle

    Science.gov (United States)

    Wang, Ten-See; Guidos, Mike

    2008-01-01

    Transient three-dimensional numerical investigations on the side load physics for an engine encompassing a film cooled nozzle extension and a regeneratively cooled thrust chamber, were performed. The objectives of this study are to identify the three-dimensional side load physics and to compute the associated aerodynamic side load using an anchored computational methodology. The computational methodology is based on an unstructured-grid, pressure-based computational fluid dynamics formulation, and a transient inlet history based on an engine system simulation. Ultimately, the computational results will be provided to the nozzle designers for estimating of effect of the peak side load on the nozzle structure. Computations simulating engine startup at ambient pressures corresponding to sea level and three high altitudes were performed. In addition, computations for both engine startup and shutdown transients were also performed for a stub nozzle, operating at sea level. For engine with the full nozzle extension, computational result shows starting up at sea level, the peak side load occurs when the lambda shock steps into the turbine exhaust flow, while the side load caused by the transition from free-shock separation to restricted-shock separation comes at second; and the side loads decreasing rapidly and progressively as the ambient pressure decreases. For the stub nozzle operating at sea level, the computed side loads during both startup and shutdown becomes very small due to the much reduced flow area.

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

    International Nuclear Information System (INIS)

    Guzman Montoto, Jose Ignacio

    2002-01-01

    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

  16. Three-dimensional MR imaging of congenital heart disease

    International Nuclear Information System (INIS)

    Laschinger, J.C.; Vannier, M.W.; Knapp, R.H.; Gutierrez, F.R.; Cox, J.L.

    1987-01-01

    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

  17. Polarization singularity anarchy in three dimensional ellipse fields

    Science.gov (United States)

    Freund, Isaac

    2004-11-01

    Lines of circular polarization, C lines, and lines of linear polarization, L lines, are studied in a computer simulated random three-dimensional ellipse field. Although we verify existing predictions for the location of particular points on these lines at which the sign of the topological index of the line inverts, we show that from the point of view of foliations of the field such points are better described as points of pair production. We find a new set of true sign inversion points, and show that when all possible foliations are considered this set includes all points on the line. We also find three new families of polarization singularities whose members include all polarization ellipses. The recently described polarization singularity democracy in two-dimensional fields evidently explodes into polarization singularity anarchy in three-dimensional fields.

  18. Three-dimensional data visualization using DSP meshes

    Science.gov (United States)

    Liow, Yuh-Tay; Civanlar, Mehmet R.; Dzik, Steven C.

    1990-08-01

    This paper presents a parallel scheme for three dimensional data visualization at interactive rates. The scheme is particularly suitable for multiprocessor systems with distributed frame buffers and is currently implemented on an AT&T Pixel Machine, a parallel computer based on mesh connected digital signal processors with a distributed frame buffer. Nearly linear performance increase with the number of processors in the mesh is obtained by partitioning the original three dimensional data into sub-blocks and processing each sub-block in parallel. The approach is very flexible in implementing a variety of visualization techniques, such as volume compositing (translucent models), binary-class and percentage mixtures and surface based volume rendering.

  19. Three-dimensional P velocity structure in Beijing area

    Science.gov (United States)

    Yu, Xiang-Wei; Chen, Yun-Tai; Wang, Pei-De

    2003-01-01

    A detail three-dimensional P wave velocity structure of Beijing, Tianjin and Tangshan area (BTT area) was determined by inverting local earthquake data. In total 16 048 P wave first arrival times from 16048 shallow and mid-depth crustal earthquakes, which occurred in and around the BTT area from 1992 to 1999 were used. The first arrival times are recorded by Northern China United Telemetry Seismic Network and Yanqing-Huailai Digital Seismic Network. Hypocentral parameters of 1 132 earthquakes with magnitude M L=1.7 6.2 and the three-dimensional P wave velocity structure were obtained simultaneously. The inversion result reveals the complicated lateral heterogeneity of P wave velocity structure around BTT area. The tomographic images obtained are also found to explain other seismological observations well.

  20. Three-dimensional Modeling of Type Ia Supernova Explosions

    Science.gov (United States)

    Khokhlov, Alexei

    2001-06-01

    A deflagration explosion of a Type Ia Supernova (SNIa) is studied using three-dimensional, high-resolution, adaptive mesh refinement fluid dynamic calculations. Deflagration speed in an exploding Chandrasekhar-mass carbon-oxygen white dwarf (WD) grows exponentially, reaches approximately 30the speed of sound, and then declines due to a WD expansion. Outermost layers of the WD remain unburned. The explosion energy is comparable to that of a Type Ia supernova. The freezing of turbulent motions by expansion appears to be a crucial physical mechanism regulating the strength of a supernova explosion. In contrast to one-dimensional models, three-dimensional calculations predict the formation of Si-group elements and pockets of unburned CO in the middle and in central regions of a supernova ejecta. This, and the presence of unburned outer layer of carbon-oxygen may pose problems for SNIa spectra. Explosion sensitivity to initial conditions and its relation to a diversity of SNIa is discussed.

  1. Ultrafast three-dimensional x-ray computed tomography

    International Nuclear Information System (INIS)

    Bieberle, Martina; Barthel, Frank; Hampel, Uwe; Menz, Hans-Juergen; Mayer, Hans-Georg

    2011-01-01

    X-ray computed tomography (CT) is a well established visualization technique in medicine and nondestructive testing. However, since CT scanning requires sampling of radiographic projections from different viewing angles, common CT systems with mechanically moving parts are too slow for dynamic imaging, for instance of multiphase flows or live animals. Here, we introduce an ultrafast three-dimensional x-ray CT method based on electron beam scanning, which achieves volume rates of 500 s -1 . Primary experiments revealed the capability of this method to recover the structure of phase boundaries in gas-solid and gas-liquid two-phase flows, which undergo three-dimensional structural changes in the millisecond scale.

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

    International Nuclear Information System (INIS)

    McCallien, C.W.J.

    1975-10-01

    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)

  3. Three-dimensional computerized tomography in mandibular condyle fractures

    International Nuclear Information System (INIS)

    Bermeo, Fausto; Salazar, Abad

    2003-01-01

    Now, car accidents are so commons, this associated to the high technology in produce automobiles make this type of accidents so serious and the consequences of mandibular condyle fractures are more commons and with more gravity, some of these patients, generally need a traqueostomy to be operated, that is why every second that we can save during the surgery is important. The normal exams as X rays and simple TAC give as an important idea but no complete, on the contrary the three-dimensional TAC permits to observe every damages and its exact location, this contribute to make a better surgery organization, the number and type of plates that we have to put and the better way to treat each case, that contribute to reduce time in operating theatre which is in benefit of the patient, diminishing risks in serious patients as they are, that is why we recommend the utilization of the three-dimensional TAC. (The author)

  4. Canonical and symplectic analysis for three dimensional gravity without dynamics

    International Nuclear Information System (INIS)

    Escalante, Alberto; Osmart Ochoa-Gutiérrez, H.

    2017-01-01

    In this paper a detailed Hamiltonian analysis of three-dimensional gravity without dynamics proposed by V. Hussain is performed. We report the complete structure of the constraints and the Dirac brackets are explicitly computed. In addition, the Faddeev–Jackiw symplectic approach is developed; we report the complete set of Faddeev–Jackiw constraints and the generalized brackets, then we show that the Dirac and the generalized Faddeev–Jackiw brackets coincide to each other. Finally, the similarities and advantages between Faddeev–Jackiw and Dirac’s formalism are briefly discussed. - Highlights: • We report the symplectic analysis for three dimensional gravity without dynamics. • We report the Faddeev–Jackiw constraints. • A pure Dirac’s analysis is performed. • The complete structure of Dirac’s constraints is reported. • We show that symplectic and Dirac’s brackets coincide to each other.

  5. Canonical and symplectic analysis for three dimensional gravity without dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Escalante, Alberto, E-mail: aescalan@ifuap.buap.mx [Instituto de Física, Benemérita Universidad Autónoma de Puebla, Apartado Postal J-48 72570, Puebla, Pue. (Mexico); Osmart Ochoa-Gutiérrez, H. [Facultad de Ciencias Físico Matemáticas, Benemérita Universidad Autónoma de Puebla, Apartado postal 1152, 72001 Puebla, Pue. (Mexico)

    2017-03-15

    In this paper a detailed Hamiltonian analysis of three-dimensional gravity without dynamics proposed by V. Hussain is performed. We report the complete structure of the constraints and the Dirac brackets are explicitly computed. In addition, the Faddeev–Jackiw symplectic approach is developed; we report the complete set of Faddeev–Jackiw constraints and the generalized brackets, then we show that the Dirac and the generalized Faddeev–Jackiw brackets coincide to each other. Finally, the similarities and advantages between Faddeev–Jackiw and Dirac’s formalism are briefly discussed. - Highlights: • We report the symplectic analysis for three dimensional gravity without dynamics. • We report the Faddeev–Jackiw constraints. • A pure Dirac’s analysis is performed. • The complete structure of Dirac’s constraints is reported. • We show that symplectic and Dirac’s brackets coincide to each other.

  6. Handwriting: three-dimensional kinetic synergies in circle drawing movements.

    Science.gov (United States)

    Hooke, Alexander W; Karol, Sohit; Park, Jaebum; Kim, Yoon Hyuk; Shim, Jae Kun

    2012-07-01

    The purpose of this study was to investigate central nervous system (CNS) strategies for controlling multifinger forces during a circle-drawing task. Subjects drew 30 concentric, discontinuous clockwise and counter clockwise circles, at self and experimenter-set paces. The three-dimensional trajectory of the pen's center of mass and the three-dimensional forces and moments of force at each contact between the hand and the pen were recorded. Uncontrolled Manifold Analysis was used to quantify the synergies between pen-hand contact forces in radial, tangential and vertical directions. Results showed that synergies in the radial and tangential components were significantly stronger than in the vertical component. Synergies in the clockwise direction were significantly stronger than the counterclockwise direction in the radial and vertical components. Pace was found to be insignificant under any condition.

  7. Secondary instability and transition in three-dimensional boundary layers

    Energy Technology Data Exchange (ETDEWEB)

    Stolte, A.; Bertolotti, F.P.; Koch, W. (Deutsche Forschungsanstalt fuer Luft- und Raumfahrt e.V. (DLR), Goettingen (Germany). Inst. fuer Stroemungsmechanik)

    1999-01-01

    Stationary and traveling crossflow modes are the most prominent disturbances in the highly accelerated three-dimensional flow near the leading edge of a swept wing. Near transition onset, secondary three-dimensional instabilities of high frequency can be observed in such flows. A model flow on the basis of a DLR swept plate experiment allows a detailed study of transition scenarios triggered by crossflow instabilities, since the favorable pressure gradient over the whole plate inhibits instabilities of Tollmien-Schlichting type. In order to shed some light upon the role of the high-frequency secondary instabilities, the saturation characteristics of crossflow vortices in this model flow are investigated using the parabolized stability equations. In contrast to nonlinear equilibrium solutions of steady crossflow vortices, the nonlinear Polarized Stability Equations (PSE) results yield different maximal disturbance amplitudes for different initial amplitudes. (orig./AKF)

  8. Secondary instability and transition in three-dimensional boundary layers

    Energy Technology Data Exchange (ETDEWEB)

    Stolte, A.; Bertolotti, F.P.; Koch, W. [Deutsche Forschungsanstalt fuer Luft- und Raumfahrt e.V. (DLR), Goettingen (Germany). Inst. fuer Stroemungsmechanik

    1999-12-01

    Stationary and traveling crossflow modes are the most prominent disturbances in the highly accelerated three-dimensional flow near the leading edge of a swept wing. Near transition onset, secondary three-dimensional instabilities of high frequency can be observed in such flows. A model flow on the basis of a DLR swept plate experiment allows a detailed study of transition scenarios triggered by crossflow instabilities, since the favorable pressure gradient over the whole plate inhibits instabilities of Tollmien-Schlichting type. In order to shed some light upon the role of the high-frequency secondary instabilities, the saturation characteristics of crossflow vortices in this model flow are investigated using the parabolized stability equations. In contrast to nonlinear equilibrium solutions of steady crossflow vortices, the nonlinear Polarized Stability Equations (PSE) results yield different maximal disturbance amplitudes for different initial amplitudes. (orig./AKF)

  9. Two-dimensional turbulence in three-dimensional flows

    Science.gov (United States)

    Xia, H.; Francois, N.

    2017-11-01

    This paper presents a review of experiments performed in three-dimensional flows that show behaviour associated with two-dimensional turbulence. Experiments reveal the presence of the inverse energy cascade in two different systems, namely, flows in thick fluid layers driven electromagnetically and the Faraday wave driven flows. In thick fluid layers, large-scale coherent structures can shear off the vertical eddies and reinforce the planarity of the flow. Such structures are either self-generated or externally imposed. In the Faraday wave driven flows, a seemingly three-dimensional flow is shown to be actually two-dimensional when it is averaged over several Faraday wave periods. In this system, a coupling between the wave motion and 2D hydrodynamic turbulence is uncovered.

  10. The thermoelectric performance of bulk three-dimensional graphene

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Zhi, E-mail: yangzhi@tyut.edu.cn [Key Lab of Advanced Transducers and Intelligent Control System, Ministry of Education and Shanxi Province, Taiyuan University of Technology, Taiyuan 030024 (China); College of Physics and Optoelectronics, Taiyuan University of Technology, Taiyuan 030024 (China); Lan, Guoqiang; Ouyang, Bin [Department of Mining and Materials Engineering, McGill University, Montreal H3A 0C5 (Canada); Xu, Li-Chun; Liu, Ruiping [College of Physics and Optoelectronics, Taiyuan University of Technology, Taiyuan 030024 (China); Liu, Xuguang, E-mail: liuxuguang@tyut.edu.cn [Key Lab of Interface Science and Engineering in Advanced Materials, Ministry of Education, Taiyuan University of Technology, Taiyuan 030024 (China); College of Chemistry and Chemical Engineering, Taiyuan University of Technology, Taiyuan 030024 (China); Song, Jun [Department of Mining and Materials Engineering, McGill University, Montreal H3A 0C5 (Canada)

    2016-11-01

    The electronic and thermoelectric properties of a new carbon bulk material, three-dimensional (3D) graphene, are investigated in this study. Our results show that 3D graphene has unique electronic structure, i.e., near the Fermi level there exist Dirac cones. More importantly, the thermoelectric performance of 3D graphene is excellent, at room temperature the thermoelectric figure of merit (ZT) is 0.21, an order of magnitude higher than that of graphene. By introducing line defects, the ZT of 3D graphene could be enhanced to 1.52, indicating 3D graphene is a powerful candidate for constructing novel thermoelectric materials. - Highlights: • There exist Dirac cones in three-dimensional (3D) graphene. • The thermoelectric performance of 3D graphene is excellent. • The defective 3D graphene has better thermoelectric performance.

  11. Three-dimensional potential energy surface of Ar–CO

    Energy Technology Data Exchange (ETDEWEB)

    Sumiyoshi, Yoshihiro, E-mail: y-sumiyoshi@gunma-u.ac.jp [Division of Pure and Applied Science, Graduate School of Science and Technology, Gunma University, 4-2 Aramaki, Maebashi, Gunma 371-8510 (Japan); Endo, Yasuki [Department of Basic Science, Graduate School of Arts and Sciences, The University of Tokyo, Komaba, Meguro-ku, Tokyo 153-8902 (Japan)

    2015-01-14

    A three-dimensional intermolecular potential energy surface of the Ar–CO complex has been determined by fitting most of the previously reported spectroscopic data, where observed transition frequencies by microwave, millimeter-wave, submillimeter-wave, and infrared spectroscopy were reproduced simultaneously within their experimental accuracies. A free rotor model Hamiltonian considering all the freedom of motions for an atom-diatom system was applied to calculate vibration-rotation energies. A three-dimensional potential energy surface obtained by ab initio calculations at the CCSD(T)-F12b/aug-cc-pV5Z level of theory was parameterized by a model function consisting of 46 parameters. They were used as initial values for the least-squares analysis of the experimental data. A total of 20 parameters were optimized to reproduce all the spectroscopic data.

  12. Three Dimensional Polarimetric Neutron Tomography of Magnetic Fields

    DEFF Research Database (Denmark)

    Sales, Morten; Strobl, Markus; Shinohara, Takenao

    2018-01-01

    -destructively with the potential to probe the interior of bulk samples which is not amenable otherwise. Using a pioneering polarimetric set-up for ToF neutron instrumentation in combination with a newly developed tailored reconstruction algorithm, the magnetic field generated by a current carrying solenoid has been measured......Through the use of Time-of-Flight Three Dimensional Polarimetric Neutron Tomography (ToF 3DPNT) we have for the first time successfully demonstrated a technique capable of measuring and reconstructing three dimensional magnetic field strengths and directions unobtrusively and non...... and reconstructed, thereby providing the proof-of-principle of a technique able to reveal hitherto unobtainable information on the magnetic fields in the bulk of materials and devices, due to a high degree of penetration into many materials, including metals, and the sensitivity of neutron polarisation to magnetic...

  13. 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.

  14. 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......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 respect to the scattering. We find that the quantum features are quite stable: the scattering by a localized scatterer will selectively smear and downshift certain quantum steps depending on the position of the scatterer, but the remaining steps will. still be at integer positions. The effect...

  15. 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.

  16. Single florescent nanodiamond in a three dimensional ABEL trap

    Science.gov (United States)

    Kayci, Metin; Radenovic, Aleksandra

    2015-01-01

    Three dimensional single particle trapping and manipulation is an outstanding challenge in various fields ranging from basic physics to life sciences. By monitoring the response of a trapped particle to a designed environment one can extract its characteristics. In addition, quantum dynamics of a spatially scanned well-known particle can provide environmental information. Precise tracking and positioning of such a particle in aqueous environment is crucial task for achieving nano-scale resolution. Here we experimentally demonstrate three dimensional ABEL trap operating at high frequency by employing a hybrid approach in particle tracking. The particle location in the transverse plane is detected via a scanning laser beam while the axial position is determined by defocused imaging. The scanning of the trapped particle is accomplished through a nano positioning stage integrated to the trap platform. PMID:26559890

  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...... of 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. Study of three-dimensional effects on vortex breakdown

    Science.gov (United States)

    Salas, M. D.; Kuruvila, G.

    1988-01-01

    The incompressible axisymmetric steady Navier-Stokes equations in primitive variables are used to simulate vortex breakdown. The equations, discretized using a second-order, central-difference scheme, are linearized and then solved using an exact LU decomposition, Gaussian elimination, and Newton iteration. Solutions are presented for Reynolds numbers, based on vortex-core radius, as high as 1500. An attempt to study the stability of the axisymmetric solutions against three-dimensional perturbations is discussed.

  19. A three-dimensional model of women's empowerment

    OpenAIRE

    Huis, Marloes A.; Hansen, Nina; Otten, Sabine; Lensink, Robert

    2017-01-01

    Women's empowerment is an important goal in achieving sustainable development worldwide. Offering access to microfinance services to women is one way to increase women's empowerment. However, empirical evidence provides mixed results with respect to its effectiveness. We reviewed previous research on the impact of microfinance services on different aspects of women's empowerment. We propose a Three-Dimensional Model of Women's Empowerment to integrate previous findings and to gain a deeper un...

  20. 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...

  1. Three Dimensional Unstructured Multigrid for the Euler Equations

    Science.gov (United States)

    1991-05-01

    represents an algorithmic issue. While much work has been performed in two dimensions on direct [21, iterative implicit [3,4,51, and multigrid methods [6,7,8...methods, and many of the iterative implicit methods incur too large memory overheads to be practical for three-dimensional problems. Multigrid methods , on...the Third Copper Mountain Confer- ence on Multigrid Methods , Lecture Notes in Pure and Applied Mathematics, Ed S. F. McCormick, Marcel Dckker Inc

  2. 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.

  3. Three-dimensional transparent parabolic concentrator for photovoltaics

    OpenAIRE

    Huichuan Lin; Peng Xie; Yong Liu; Xiang Zhou; Baojun Li

    2015-01-01

    A three-dimensional transparent parabolic concentrator made of polymethylmethacrylate (PMMA) was designed and fabricated for photovoltaic applications. The measured maximum concentration ratio of the concentrator is 8.31, which means that for normal incident light, optical energy can be concentrated as high as 8.31 times by the concentrator. Even for oblique incident lights with an incident angle of between 5° and 15°, the concentrator maintains a concentration ratio of between 6.81 and 3.72....

  4. Aerodynamics of Airfoils Subject to Three-Dimensional Periodic Gusts.

    Science.gov (United States)

    1983-08-31

    and computational procedures to calculate the unsteady forces acting upon airfoils of arbitrary shape subject to three-dimensional gust disturbances...However the mathenatical formulation which has evolved from our analytical work can also be applied under certain conditions to study the changes in...check the validity of our computation scheme two sets of comparisons were carried out. First we considered a two-dimensional gust with transverse and

  5. 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.

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

    Directory of Open Access Journals (Sweden)

    Matiur Rahman

    1990-01-01

    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.

  7. Functional renormalization group for three-dimensional quantum magnetism

    Science.gov (United States)

    Iqbal, Yasir; Thomale, Ronny; Parisen Toldin, Francesco; Rachel, Stephan; Reuther, Johannes

    2016-10-01

    We formulate a pseudofermion functional renormalization group (PFFRG) scheme to address frustrated quantum magnetism in three dimensions. In a scenario where many numerical approaches fail due to sign problem or small system size, three-dimensional (3D) PFFRG allows for a quantitative investigation of the quantum spin problem and its observables. We illustrate 3D PFFRG for the simple cubic J1-J2-J3 quantum Heisenberg antiferromagnet, and benchmark it against other approaches, if available.

  8. Three dimensional refractive index imaging with differential interference contrast microscopy

    Science.gov (United States)

    Aung, Htet; Buckley, Jared; Kostyk, Piotr; Rodriguez, Braulio; Phelan, Shelley; Xu, M.

    2012-03-01

    We report here a new approach based on an extension of the transport of the intensity equation for three dimensional refractive index imaging of a weak phase object from a series of images recorded by a differential interference contrast microscope at different focus (z-stack). Our method is first validated by imaging polystyrene spheres. We then apply this method to monitor in vivo apoptosis of human breast MCF7 epithelial cells. The potential applications are discussed at the end.

  9. Three-dimensional friction measurement during hip simulation.

    Directory of Open Access Journals (Sweden)

    Robert Sonntag

    Full Text Available Wear of total hip replacements has been the focus of many studies. However, frictional effects, such as high loading on intramodular connections or the interface to the bone, as well as friction associated squeaking have recently increased interest about the amount of friction that is generated during daily activities. The aim of this study was thus to establish and validate a three-dimensional friction setup under standardized conditions.A standard hip simulator was modified to allow for high precision measurements of small frictional effects in the hip during three-dimensional hip articulation. The setup was verified by an ideal hydrostatic bearing and validated with a static-load physical pendulum and an extension-flexion rotation with a dynamic load profile. Additionally, a pendulum model was proposed for screening measurement of frictional effects based on the damping behavior of the angular oscillation without the need for any force/moment transducer. Finally, three-dimensional friction measurements have been realized for ceramic-on-polyethylene bearings of three different sizes (28, 36 and 40 mm.A precision of less than 0.2 Nm during three-dimensional friction measurements was reported, while increased frictional torque (resultant as well as taper torque was measured for larger head diameters. These effects have been confirmed by simple pendulum tests and the theoretical model. A comparison with current literature about friction measurements is presented.This investigation of friction is able to provide more information about a field that has been dominated by the reduction of wear. It should be considered in future pre-clinical testing protocols given by international organizations of standardization.

  10. 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...... and otosclerotic bone remodeling suggests that inner ear mechanisms in control of bone remodeling may have a pathogenetic role in otosclerosis....

  11. Three-dimensional, computer simulated navigation in endoscopic neurosurgery

    Directory of Open Access Journals (Sweden)

    Roberta K. Sefcik, BHA

    2017-06-01

    Conclusion: Three-dimensional, frameless neuronavigation systems are useful in endoscopic neurosurgery to assist in the pre-operative planning of potential trajectories and to help localize the pathology of interest. Neuronavigation appears to be accurate to <1–2 mm without issues related to brain shift. Further work is necessary in the investigation of the effect of neuronavigation on operative time, cost, and patient-centered outcomes.

  12. Accuracy of three-dimensional printing for manufacturing replica teeth

    OpenAIRE

    Lee, Keun-Young; Cho, Jin-Woo; Chang, Na-Young; Chae, Jong-Moon; Kang, Kyung-Hwa; Kim, Sang-Cheol; Cho, Jin-Hyoung

    2015-01-01

    Objective Three-dimensional (3D) printing is a recent technological development that may play a significant role in orthodontic diagnosis and treatment. It can be used to fabricate skull models or study models, as well as to make replica teeth in autotransplantation or tooth impaction cases. The aim of this study was to evaluate the accuracy of fabrication of replica teeth made by two types of 3D printing technologies. Methods Fifty extracted molar teeth were selected as samples. They were sc...

  13. Is a three-dimensional-printed tooth filling possible?

    OpenAIRE

    Muhammet Kerim Ayar

    2016-01-01

    Introduction: Three-dimensional (3-D) printing is seen as an innovative production process in many fields of dentistry and medicine. But implantation of this novel production process into the treatment of decayed teeth in dentistry remains lacking. Destruction of dental tissues as a result of dental caries is generally treated with dental resin composite fillings. However, a 3-D-printed tooth filling approach, which could be an alternative to traditional approaches, has a potential to reduce ...

  14. Tailor-made three-dimensional hybrid scaffolds for cell cultures

    International Nuclear Information System (INIS)

    Psycharakis, Stylianos; Melissinaki, Vasileia; Giakoumaki, Anastasia; Ranella, Anthi; Tosca, Androniki

    2011-01-01

    The construction of the ideal three-dimensional scaffold for cell culture is one of the most intriguing topics in tissue engineering. It has been shown that cells can be cultured on most organic biomimetic materials, which now are losing popularity in favour of novel, hybrid systems. In this study, a series of photosensitive sol-gel hybrid materials, based on silicon-zirconium and silicon-titanium oxides, have been investigated for their suitability in three-dimensional scaffold fabrication. These materials can be structured by two-photon polymerization, a laser-based technique allowing the fabrication of micrometre-size structures with submicron resolution. The work presented here examined the effect of the organic/inorganic composition of the materials on cell behaviour and the establishment of a 'cell-culture friendly' environment. This is vital for cell adhesion, growth and differentiation, as the organic part of the material provides the soft matrix for cell growth, whereas the inorganic component gives the mechanical stability and rigidity of the three-dimensional structures. In addition, the use of femtosecond laser structuring permits the fabrication of a wide range of mechanically stable scaffolds of different sizes and shapes to be tested in terms of cell viability, proliferation and orientation.

  15. [Tip and torque changes in maxillary buccal segment after orthodontic treatment: a three-dimensional study].

    Science.gov (United States)

    Chen, Gui; Qin, Yi-fei; Xu, Tian-min

    2010-11-01

    To investigate three-dimensional imaging registration and superimposition techniques in measuring the tip and torque change of upper canine, premolar and first molar after orthodontic treatment. Twenty-eight subjects (14 extraction cases and 14 non-extraction cases) with full records were randomly selected from the Department of Orthodontics, Peking University School and Hospital of Stomatology. The pre-and post-treatment upper dental casts were digitized with three-dimensional spot laser scanner and superimposed with reverse engineering software. The facial axis of the clinical crown (FACC) was transferred from post-treatment teeth to the pre-treatment teeth using three-dimensional imaging registration. The occlusal plane was constructed on the post-treatment upper digital cast and the tip and torque values were measured. In the non-extraction group, the tip of the second premolar decreased by 1.5° (P orthodontic treatment tended to tip the upper second premolar distally and increased the buccal crown torque of the upper premolars while extraction treatment increased the lingual crown torque of the upper canine.

  16. 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.

  17. 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.

  18. Comparison of two three-dimensional cephalometric analysis computer software.

    Science.gov (United States)

    Sawchuk, Dena; Alhadlaq, Adel; Alkhadra, Thamer; Carlyle, Terry D; Kusnoto, Budi; El-Bialy, Tarek

    2014-10-01

    Three-dimensional cephalometric analyses are getting more attraction in orthodontics. The aim of this study was to compare two softwares to evaluate three-dimensional cephalometric analyses of orthodontic treatment outcomes. Twenty cone beam computed tomography images were obtained using i-CAT(®) imaging system from patient's records as part of their regular orthodontic records. The images were analyzed using InVivoDental5.0 (Anatomage Inc.) and 3DCeph™ (University of Illinois at Chicago, Chicago, IL, USA) software. Before and after orthodontic treatments data were analyzed using t-test. Reliability test using interclass correlation coefficient was stronger for InVivoDental5.0 (0.83-0.98) compared with 3DCeph™ (0.51-0.90). Paired t-test comparison of the two softwares shows no statistical significant difference in the measurements made in the two softwares. InVivoDental5.0 measurements are more reproducible and user friendly when compared to 3DCeph™. No statistical difference between the two softwares in linear or angular measurements. 3DCeph™ is more time-consuming in performing three-dimensional analysis compared with InVivoDental5.0.

  19. Space charge cartography by FLIMM: a three-dimensional approach

    International Nuclear Information System (INIS)

    Marty-Dessus, D; Berquez, L; Petre, A; Franceschi, J L

    2002-01-01

    A technique for three-dimensional cartography of space charges profiles inside polymer insulating samples is proposed. Called focused laser intensity modulation method (FLIMM), it is derived from the well-known LIMM method, with an additional possibility of being able to focus the laser spot on the surface of the sample to be studied. The processed data is a short-circuited pyrolectric current collected between the electrodes and induced by the interaction of the charges with the periodic variations of temperature produced by the laser source. The focused aspect of our method requires a good three-dimensional modelling of the spatial evolution of this thermal gradient. Under these conditions, the treatment of the equation of heat propagation is carried out using simultaneously a double Fourier transform and Green functions. In association with the numerical simulations of this solution, a two-dimensional scanning of the beam on polyethylene test sample surfaces shows that one can get three-dimensional representations of space charge shapes with a lateral resolution lower than 10 μm and for a depth of analysis typically included in the range 1-100 μm

  20. 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.

  1. Three-Dimensionally Isotropic Negative Refractive Index Materials from Block Copolymer Self-Assembled Chiral Gyroid Networks

    KAUST Repository

    Hur, Kahyun

    2011-10-17

    Metamaterials are engineered artificial materials that offer new functionalities such as super-resolution imaging and cloaking. Calculations of the photonic properties of three-dimensionally isotropic metamaterials with cubic double gyroid and alternating gyroid morphologies from block copolymer self-assembly are presented.

  2. In vitro fabrication of functional three-dimensional tissues with perfusable blood vessels.

    Science.gov (United States)

    Sekine, Hidekazu; Shimizu, Tatsuya; Sakaguchi, Katsuhisa; Dobashi, Izumi; Wada, Masanori; Yamato, Masayuki; Kobayashi, Eiji; Umezu, Mitsuo; Okano, Teruo

    2013-01-01

    In vitro fabrication of functional vascularized three-dimensional tissues has been a long-standing objective in the field of tissue engineering. Here we report a technique to engineer cardiac tissues with perfusable blood vessels in vitro. Using resected tissue with a connectable artery and vein as a vascular bed, we overlay triple-layer cardiac cell sheets produced from coculture with endothelial cells, and support the tissue construct with media perfused in a bioreactor. We show that endothelial cells connect to capillaries in the vascular bed and form tubular lumens, creating in vitro perfusable blood vessels in the cardiac cell sheets. Thicker engineered tissues can be produced in vitro by overlaying additional triple-layer cell sheets. The vascularized cardiac tissues beat and can be transplanted with blood vessel anastomoses. This technique may create new opportunities for in vitro tissue engineering and has potential therapeutic applications.

  3. Three-dimensional appearance of the lips muscles with three-dimensional isotropic MRI: in vivo study.

    Science.gov (United States)

    Olszewski, Raphael; Liu, Y; Duprez, T; Xu, T M; Reychler, H

    2009-06-01

    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.

  4. Clinical Application of Three-Dimensional Printing Technology in Craniofacial Plastic Surgery

    OpenAIRE

    Choi, Jong Woo; Kim, Namkug

    2015-01-01

    Three-dimensional (3D) printing has been particularly widely adopted in medical fields. Application of the 3D printing technique has even been extended to bio-cell printing for 3D tissue/organ development, the creation of scaffolds for tissue engineering, and actual clinical application for various medical parts. Of various medical fields, craniofacial plastic surgery is one of areas that pioneered the use of the 3D printing concept. Rapid prototype technology was introduced in the 1990s to m...

  5. The use of three-dimensional printing technology in orthopaedic surgery.

    Science.gov (United States)

    Wong, Tak Man; Jin, Jimmy; Lau, Tak Wing; Fang, Christian; Yan, Chun Hoi; Yeung, Kelvin; To, Michael; Leung, Frankie

    2017-01-01

    Three-dimensional (3-D) printing or additive manufacturing, an advanced technology that 3-D physical models are created, has been wildly applied in medical industries, including cardiothoracic surgery, cranio-maxillo-facial surgery and orthopaedic surgery. The physical models made by 3-D printing technology give surgeons a realistic impression of complex structures, allowing surgical planning and simulation before operations. In orthopaedic surgery, this technique is mainly applied in surgical planning especially revision and reconstructive surgeries, making patient-specific instruments or implants, and bone tissue engineering. This article reviews this technology and its application in orthopaedic surgery.

  6. Comparison of Wenner and dipole–dipole arrays in the study of an underground three-dimensional cavity

    International Nuclear Information System (INIS)

    Neyamadpour, Ahmad; Wan Abdullah, W A T; Taib, Samsudin; Neyamadpour, Behrang

    2010-01-01

    The objective of this paper was to compare Wenner and dipole–dipole configurations in delineating an underground cavity at a site near the University of Malaya, Malaysia. A three-dimensional electrical resistivity imaging survey was carried out along seven parallel lines using Wenner and dipole–dipole arrays. A three-dimensional least-squares algorithm, based on the robust inversion method, was used in the inversion of the apparent resistivity data. In the inverted model, both the horizontal and vertical extents of the anomalous zones were displayed. Results indicate the superiority of the Wenner array over the dipole–dipole array for determining the vertical distribution of the subsurface resistivity, although the dipole–dipole array produced a better lateral extent of the subsurface features. The results show that the three-dimensional electrical resistivity imaging survey using both the Wenner and dipole–dipole arrays, in combination with an appropriate three-dimensional inversion method and synthetic model analysis, can be highly useful for engineering and environmental applications, especially for underground three-dimensional cavity detection

  7. Asymmetric three-dimensional topography over mantle plumes.

    Science.gov (United States)

    Burov, Evgueni; Gerya, Taras

    2014-09-04

    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.

  8. Three-dimensional trajectory optimization in constrained airspace

    Science.gov (United States)

    Dai, Ran

    This dissertation deals with the generation of three-dimensional optimized trajectory in constrained airspace. It expands the previously used two-dimensional aircraft model to a three-dimensional model and includes the consideration of complex airspace constraints not included in previous trajectory optimization studies. Two major branches of optimization methods, indirect and direct methods, are introduced and compared. Both of the methods are applied to solve a two-dimensional minimum-time-to-climb (MTTC) problem. The solution procedure is described in detail. Two traditional problems, the Brachistochrone problem and Zermelo's problem, are solved using the direct collocation and nonlinear programming method. Because analytical solutions to these problems are known. These solutions provide verification of the numerical methods. Three discretization methods, trapezoidal, Hermite-Simpson and Chebyshev Pseudospectral (CP) are introduced and applied to solve the Brachistochrone problem. The solutions obtained using these discretization methods are compared with the analytical results. An 3-D aircraft model with six state variables and two control variables are presented. Two primary trajectory optimization problems are considered using this model in the dissertation. One is to assume that the aircraft climbs up from sea level to a desired altitude in a square cross section cylinder of arbitrary height. Another is to intercept a constant velocity, constant altitude target in minimum time starting from sea level. Results of the optimal trajectories are compared with the results from the proportional navigation guidance law. Field of View constraint is finally considered in this interception problem. The CP discretization and nonlinear programming method is shown to have advantages over indirect methods in solving three-dimensional (3-D) trajectory optimization problems with multiple controls and complex constraints. Conclusions from both problems are presented and

  9. Lyapunov Schmidt reduction algorithm for three-dimensional discrete vortices

    Science.gov (United States)

    Lukas, Mike; Pelinovsky, Dmitry; Kevrekidis, P. G.

    2008-03-01

    We address the persistence and stability of three-dimensional vortex configurations in the discrete nonlinear Schrödinger equation and develop a symbolic package based on Wolfram’s MATHEMATICA for computations of the Lyapunov-Schmidt reduction method. The Lyapunov-Schmidt reduction method is a theoretical tool which enables us to study continuations and terminations of the discrete vortices for small coupling between lattice nodes as well as the spectral stability of the persistent configurations. The method was developed earlier in the context of the two-dimensional lattice and applied to the onsite and offsite configurations (called the vortex cross and the vortex cell) by using semianalytical computations [D.E. Pelinovsky, P.G. Kevrekidis, D. Frantzeskakis, Physica D 212 (2005) 20-53; P.G. Kevrekidis, D.E. Pelinovsky, Proc. R. Soc. A 462 (2006) 2671-2694]. The present treatment develops a full symbolic computational package which takes a desired waveform at the anticontinuum limit of uncoupled sites, performs a required number of Lyapunov-Schmidt reductions and outputs the predictions on whether the configuration persists, for finite coupling, in the three-dimensional lattice and whether it is stable or unstable. It also provides approximations for the eigenvalues of the linearized stability problem. We report a number of applications of the algorithm to important multisite three-dimensional configurations, such as the simple cube, the double cross and the diamond. For each configuration, we identify exactly one solution, which is stable for small coupling between lattice nodes.

  10. Observation of three dimensional optical rogue waves through obstacles

    Energy Technology Data Exchange (ETDEWEB)

    Leonetti, Marco, E-mail: marco.leonetti@roma1.infn.it [Center for Life Nano Science@Sapienza, Istituto Italiano di Tecnologia, Viale Regina Elena, 291 00161 Roma (RM) (Italy); Conti, Claudio [ISC-CNR and Department of Physics, University Sapienza, P.le Aldo Moro 5, I-00185 Roma (Italy)

    2015-06-22

    We observe three-dimensional rogue waves in the speckle distribution of a spatially modulated optical beam. Light is transmitted beyond a partially reflecting obstacle generating optical rogue waves at a controlled position in the shadow of the barrier. When the barrier transmits only 0.07% of the input laser power, we observe the mostly localized event. These results demonstrate that an optimum amount of spatial non-homogeneity maximizes the probability of a gigantic event while the technique we exploit enables to control light behind a fully reflective wall.

  11. Surgical accuracy of three-dimensional virtual planning

    DEFF Research Database (Denmark)

    Stokbro, Kasper; Aagaard, Esben; Torkov, Peter

    2016-01-01

    This retrospective study evaluated the precision and positional accuracy of different orthognathic procedures following virtual surgical planning in 30 patients. To date, no studies of three-dimensional virtual surgical planning have evaluated the influence of segmentation on positional accuracy...... and transverse expansion. Furthermore, only a few have evaluated the precision and accuracy of genioplasty in placement of the chin segment. The virtual surgical plan was compared with the postsurgical outcome by using three linear and three rotational measurements. The influence of maxillary segmentation...

  12. Quantum tunneling from three-dimensional black holes

    International Nuclear Information System (INIS)

    Ejaz, Asiya; Gohar, H.; Lin, Hai; Saifullah, K.; Yau, Shing-Tung

    2013-01-01

    We study Hawking radiation from three-dimensional black holes. For this purpose the emission of charged scalar and charged fermionic particles is investigated from charged BTZ black holes, with and without rotation. We use the quantum tunneling approach incorporating WKB approximation and spacetime symmetries. Another class of black holes which is asymptotic to a Sol three-manifold has also been investigated. This procedure gives us the tunneling probability of outgoing particles, and we compute the temperature of the radiation for these black holes. We also consider the quantum tunneling of particles from black hole asymptotic to Sol geometry

  13. Modified Three-Dimensional Multicarrier Optical Prime Codes

    Directory of Open Access Journals (Sweden)

    Rajesh Yadav

    2016-01-01

    Full Text Available We propose a mathematical model for novel three-dimensional multicarrier optical codes in terms of wavelength/time/space based on the prime sequence algorithm. The proposed model has been extensively simulated on MATLAB for prime numbers (P to analyze the performance of code in terms of autocorrelation and cross-correlation. The simulated outcome resembles the mathematical model and gives better results over other methods available in the literature as far as autocorrelation and cross-correlation are concerned. The proposed 3D optical codes are more efficient in terms of cardinality, improved security, and providing quality of services.

  14. Three-dimensional display techniques: description and critique of methods

    International Nuclear Information System (INIS)

    Budinger, T.F.

    1982-01-01

    The recent advances in non invasive medical imaging of 3 dimensional spatial distribution of radionuclides, X-ray attenuation coefficients, and nuclear magnetic resonance parameters necessitate development of a general method for displaying these data. The objective of this paper is to give a systematic description and comparison of known methods for displaying three dimensional data. The discussion of display methods is divided into two major categories: 1) computer-graphics methods which use a two dimensional display screen; and 2) optical methods (such as holography, stereopsis and vari-focal systems)

  15. Impurity states in two and three dimensional disordered system S

    International Nuclear Information System (INIS)

    Silva, A.F. da; Fabbri, M.

    1984-01-01

    We investigate the microscopic structure of the impurity states in two-and three-dimensional (2D and 3D) disordered system. A cluster model is outlined for the donor impurity density of states (DIDS) of doped semiconductors. It is shown that the impurity states are very sensitive to a change in the dimensionality of the system, i.e., from 3D to 2D system. It is found that all eigenstates become localized in 2D disordered system for a large range of concentration. (author) [pt

  16. Three-dimensional analysis of two-pile caps

    Directory of Open Access Journals (Sweden)

    T.E.T. Buttignol

    Full Text Available This paper compares the results between a non-linear three-dimensional numerical analysis of pile caps with two piles and the experimental study conducted by Delalibera. It is verified the load-carrying capacity, the crack pattern distribution, the principal stress in concrete and steel, the deflection and the fracture of the pile cap. The numerical analysis is executed with the finite-element software ATENA 3D, considering a perfect bond between concrete and steel. The numerical and experimental results are presented and have demonstrated a good approximation, reasserting the results of the experimental model and corroborating the theory.

  17. Three-dimensional fractional topological insulators in coupled Rashba layers

    Science.gov (United States)

    Volpez, Yanick; Loss, Daniel; Klinovaja, Jelena

    2017-08-01

    We propose a model of three-dimensional topological insulators consisting of weakly coupled electron- and hole-gas layers with Rashba spin-orbit interaction stacked along a given axis. We show that in the presence of strong electron-electron interactions the system realizes a fractional strong topological insulator, where the rotational symmetry and condensation energy arguments still allow us to treat the problem as quasi-one-dimensional with bosonization techniques. We also show that if Rashba and Dresselhaus spin-orbit interaction terms are equally strong, by doping the system with magnetic impurities, one can bring it into the Weyl semimetal phase.

  18. Tag gas burnup based on three-dimensional FTR analysis

    International Nuclear Information System (INIS)

    Kidman, R.B.

    1976-01-01

    Flux spectra from a three-dimensional diffusion theory analysis of the Fast Test Reactor (FTR) are used to predict gas tag ratio changes, as a function of exposure, for each FTR fuel and absorber subassembly plenum. These flux spectra are also used to predict Xe-125 equilibrium activities in absorber plena in order to assess the feasibility of using Xe-125 gamma rays to detect and distinguish control rod failures from fuel rod failures. Worst case tag burnup changes are used in conjunction with burnup and mass spectrometer uncertainties to establish the minimum spacing of tags which allows the tags to be unambiguously identified

  19. Photonic Paint Developed with Metallic Three-Dimensional Photonic Crystals

    Science.gov (United States)

    Sun, Po; Williams, John D.

    2012-01-01

    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.

  20. Fracture of three-dimensional fuse networks with quenched disorder

    OpenAIRE

    Räisänen, V. I.; Alava, M. J.; Nieminen, Risto M.

    1998-01-01

    We study a fracture on a quasistatic time scale in a three-dimensional (3D) fuse network model with “strong” and “weak” disorder. These two cases differ noticeably in the development of the fracture. For strong disorder the damage scaling is very close to volumelike [number of broken bonds Nb∼L3/(lnL)0.3] unlike for weak disorder [Nb∼L2.4/(lnL)0.3]. With strong disorder global load sharing is only approximately valid. The size distribution of “avalanches” of broken fuses in the failure follow...

  1. Three-dimensional characterization of stress corrosion cracks

    DEFF Research Database (Denmark)

    Lozano-Perez, S.; Rodrigo, P.; Gontard, Lionel Cervera

    2011-01-01

    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......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. Three-dimensional laser pulse intensity diagnostic for photoinjectors

    Directory of Open Access Journals (Sweden)

    Heng Li

    2011-11-01

    Full Text Available Minimizing the electron-beam emittance of photoinjectors is an important task for maximizing the brightness of the next-generation x-ray facilities, such as free-electron lasers and energy recovery linacs. Optimally shaped laser pulses can significantly reduce emittance. A reliable diagnostic for the laser pulse intensity is required for this purpose. We demonstrate measurement of three-dimensional spatiotemporal intensity profiles, with spatial resolution of 20  μm and temporal resolution of 130 fs. The capability is illustrated by measurements of stacked soliton pulses and pulses from a dissipative-soliton laser.

  3. Teaching veterinary obstetrics using three-dimensional animation technology.

    Science.gov (United States)

    Scherzer, Jakob; Buchanan, M Flint; Moore, James N; White, Susan L

    2010-01-01

    In this three-year study, test scores for students taught veterinary obstetrics in a classroom setting with either traditional media (photographs, text, and two-dimensional graphical presentations) were compared with those for students taught by incorporating three-dimensional (3D) media (linear animations and interactive QuickTime Virtual Reality models) into the classroom lectures. Incorporation of the 3D animations and interactive models significantly increased students' scores on essay questions designed to assess their comprehension of the subject matter. This approach to education may help to better prepare students for dealing with obstetrical cases during their final clinical year and after graduation.

  4. Coherent states on horospheric three-dimensional Lobachevsky space

    Energy Technology Data Exchange (ETDEWEB)

    Kurochkin, Yu., E-mail: y.kurochkin@ifanbel.bas-net.by; Shoukavy, Dz., E-mail: shoukavy@ifanbel.bas-net.by [Institute of Physics, National Academy of Sciences of Belarus, 68 Nezalezhnasci Ave., Minsk 220072 (Belarus); Rybak, I., E-mail: Ivan.Rybak@astro.up.pt [Institute of Physics, National Academy of Sciences of Belarus, 68 Nezalezhnasci Ave., Minsk 220072 (Belarus); Instituto de Astrofísica e Ciências do Espaço, CAUP, Rua das Estrelas, 4150-762 Porto (Portugal); Faculdade de Ciências, Universidade do Porto, Rua do Campo Alegre 687, 4169-007 Porto (Portugal)

    2016-08-15

    In the paper it is shown that due to separation of variables in the Laplace-Beltrami operator (Hamiltonian of a free quantum particle) in horospheric and quasi-Cartesian coordinates of three dimensional Lobachevsky space, it is possible to introduce standard (“conventional” according to Perelomov [Generalized Coherent States and Their Applications (Springer-Verlag, 1986), p. 320]) coherent states. Some problems (oscillator on horosphere, charged particle in analogy of constant uniform magnetic field) where coherent states are suitable for treating were considered.

  5. Three-Dimensional Magnetohydrodynamic Simulation of Slapper Initiation Systems

    Energy Technology Data Exchange (ETDEWEB)

    Christensen, J S; Hrousis, C A

    2010-03-09

    Although useful information can be gleaned from 2D and even 1D simulations of slapper type initiation systems, these systems are inherently three-dimensional and therefore require full 3D representation to model all relevant details. Further, such representation provides additional insight into optimizing the design of such devices from a first-principles perspective and can thereby reduce experimental costs. We discuss in this paper several ongoing efforts in modeling these systems, our pursuit of validation, and extension of these methods to other systems. Our results show the substantial dependence upon highly accurate global equations of state and resistivity models in these analyses.

  6. Field approach to three-dimensional gene expression pattern characterization

    Science.gov (United States)

    Costa, L. da F.; Travençolo, B. A. N.; Azeredo, A.; Beletti, M. E.; Müller, G. B.; Rasskin-Gutman, D.; Sternik, G.; Ibañes, M.; Izpisúa-Belmonte, J. C.

    2005-04-01

    We present a vector field method for obtaining the spatial organization of three-dimensional patterns of gene expression based on gradients and lines of force obtained by numerical integration. The convergence of these lines of force in local maxima are centers of gene expression, providing a natural and powerful framework to characterize the organization and dynamics of biological structures. We apply this methodology to analyze the expression pattern of the enhanced green fluorescent protein (EGFP) driven by the promoter of light chain myosin II during zebrafish heart formation.

  7. Self-assembled three-dimensional chiral colloidal architecture

    Science.gov (United States)

    Ben Zion, Matan Yah; He, Xiaojin; Maass, Corinna C.; Sha, Ruojie; Seeman, Nadrian C.; Chaikin, Paul M.

    2017-11-01

    Although stereochemistry has been a central focus of the molecular sciences since Pasteur, its province has previously been restricted to the nanometric scale. We have programmed the self-assembly of micron-sized colloidal clusters with structural information stemming from a nanometric arrangement. This was done by combining DNA nanotechnology with colloidal science. Using the functional flexibility of DNA origami in conjunction with the structural rigidity of colloidal particles, we demonstrate the parallel self-assembly of three-dimensional microconstructs, evincing highly specific geometry that includes control over position, dihedral angles, and cluster chirality.

  8. 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.

  9. Conoscopic holography: toward three-dimensional reconstructions of opaque objects.

    Science.gov (United States)

    Mugnier, L M

    1995-03-10

    Conoscopic holography is an interferometric technique that permits the recording of three-dimensional objects. A two-step scheme is presented to recover an opaque object's shape from its conoscopic hologram, consisting of a reconstruction algorithm to give a first estimate of the shape and an iterative restoration procedure that uses the object's support information to make the reconstruction more robust. The existence, uniqueness, and stability of the solution, as well as the convergence of the restoration algorithm, are studied. A preliminary experimental result is presented.

  10. 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.

  11. Proton beam writing of three-dimensional microcavities

    International Nuclear Information System (INIS)

    Vanga, S.K.; Bettiol, A.A.

    2013-01-01

    Optical micro cavities exhibit high quality factors due to the circulation of resonant optical fields within the cavity. Polymers are good materials for the fabrication of micro cavities for practical applications due to the availability of various refractive indices and their low cost. Polymer micro cavities generally yield low Q-factors compared to semiconductor materials because of inherent material absorption losses, and their Q-factors are limited by the low index contrast between the polymer and the substrate material. In the present work, three dimensional micro cavities were fabricated in SU-8 using proton beam writing to enhance the index contrast by isolating the cavities from the substrate

  12. Three-dimensional imaging techniques: A literature review

    Science.gov (United States)

    Karatas, Orhan Hakki; Toy, Ebubekir

    2014-01-01

    Imaging is one of the most important tools for orthodontists to evaluate and record size and form of craniofacial structures. Orthodontists routinely use 2-dimensional (2D) static imaging techniques, but deepness of structures cannot be obtained and localized with 2D imaging. Three-dimensional (3D) imaging has been developed in the early of 1990's and has gained a precious place in dentistry, especially in orthodontics. The aims of this literature review are to summarize the current state of the 3D imaging techniques and to evaluate the applications in orthodontics. PMID:24966761

  13. The Electron in Three-Dimensional Momentum Space

    Science.gov (United States)

    Mantovani, L.; Bacchetta, A.; Pasquini, B.

    2016-07-01

    We study the electron as a system composed of an electron and a photon and derive the leading-twist transverse-momentum-dependent distribution functions for both the electron and photon in the dressed electron, thereby offering a three-dimensional description of the dressed electron in momentum space. To obtain the distribution functions, we apply both the formalism of light-front wave function overlap representation and the diagrammatic approach; we discuss the comparison of our results between light-cone gauge and Feynman gauge, discussing the role of the Wilson lines to obtain gauge-independent results. We provide examples of plots of the computed distributions.

  14. Turbulence in Three Dimensional Simulations of Magnetopause Reconnection

    Science.gov (United States)

    Drake, J. F.; Price, L.; Swisdak, M.; Burch, J. L.; Cassak, P.; Dahlin, J. T.; Ergun, R.

    2017-12-01

    We present two- and three-dimensional particle-in-cell simulations of the 16 October 2015 MMS magnetopause reconnection event. While the two-dimensional simulation is laminar, turbulence develops at both the x-line and along the magnetic separatrices in the three-dimensional simulation. This turbulence is electromagnetic in nature, is characterized by a wavevector k given by kρ e ˜(m_e/m_i)0.25 with ρ e the electron Larmor radius, and appears to have the ion pressure gradient as its source of free energy. Taken together, these results suggest the instability is a variant of the lower-hybrid drift instability. The turbulence produces electric field fluctuations in the out-of-plane direction (the direction of the reconnection electric field) with an amplitude of around ± 10 mV/m, which is much greater than the reconnection electric field of around 0.1 mV/m. Such large values of the out-of-plane electric field have been identified in the MMS data. The turbulence in the simulation controls the scale lengths of the density profile and current layers in asymmetric reconnection, driving them closer to √ {ρ eρ_i } than the ρ e or de scalings seen in 2D reconnection simulations, where de is the electron inertial length. The turbulence is strong enough to make the magnetic field around the reconnection island chaotic and produces both anomalous resistivity and anomalous viscosity. Each contribute significantly to breaking the frozen-in condition in the electron diffusion region. The crescent-shaped features in velocity space seen both in MMS observations and in two-dimensional simulations survive, even in the turbulent environment of the three-dimensional system. We compare and contrast these results to a three-dimensional simulation of the 8 December 2015 MMS magnetopause reconnection event in which the reconnecting and out-of-plane guide fields are comparable. LHDI is still present in this event, although its appearance is modified by the presence of the guide

  15. Three-Dimensional Bone Adaptation of the Proximal Femur

    DEFF Research Database (Denmark)

    Bagge, Mette

    1998-01-01

    The bone remodeling of a three-dimensional model of the proximal femur is considered. The bone adaptation is numerically described as an evolution in time formulated such that the structural change goes in an optimal direction within each time step for the optimal boundary conditions. In the bone...... remodeling scheme is included the memory of past loadings to account for the delay in the bone response to the load changes. In order to get a realistic bone adaptation process, the bone structure at the onset of the remodeling needs to be realistic too. A start design is obtained by structural optimization...

  16. Plenoptic Imaging of a Three Dimensional Cold Atom Cloud

    Science.gov (United States)

    Lott, Gordon

    2017-04-01

    A plenoptic imaging system is capable of sampling the rays of light in a volume, both spatially and angularly, providing information about the three dimensional (3D) volume being imaged. The extraction of the 3D structure of a cold atom cloud is demonstrated, using a single plenoptic camera and a single image. The reconstruction is tested against a reference image and the results discussed along with the capabilities and limitations of the imaging system. This capability is useful when the 3D distribution of the atoms is desired, such as determining the shape of an atom trap, particularly when there is limited optical access. Gratefully acknowledge support from AFRL.

  17. Three-dimensional, subsurface imaging synthetic aperture radar

    International Nuclear Information System (INIS)

    Moussally, G.J.

    1994-01-01

    The objective of this applied research and devolpment project is to develop a system known as 3-D SISAR. This sytem consists of a gound penetrating radar with software algorithms designed for detection, location, and identification of buried objects in the underground hazardous waste environments found at US DOE storage sites. Three-dimensional maps can assist the development of remdiation strategies and characterization of the digface during remediation. The system should also be useful for monitoring hydrocarbon-based contaminant migration after remediation. 5 figs

  18. Digital Simulation of Thunder from Three-Dimensional Lightning

    Science.gov (United States)

    Dunkin, James; Fleisch, Daniel

    2010-04-01

    The physics of lightning and its resultant thunder have been investigated by many people, but we still don't have a full understanding of the governing processes. In this study, we have constructed a three-dimensional model of lightning using MATLAB^ software, and used N-waves as postulated by Ribner and Roy to synthesize the resultant thunder signature. In addition, we have taken an FFT of the thunder signature, and compared the time-domain waveform and frequency spectrum to recordings of thunder taken over the summer of 2009. This analysis is done with the goal of further understanding the processes of thunder production.

  19. Three dimensional magnetic solutions in massive gravity with (nonlinear field

    Directory of Open Access Journals (Sweden)

    S.H. Hendi

    2017-12-01

    Full Text Available The Noble Prize in physics 2016 motivates one to study different aspects of topological properties and topological defects as their related objects. Considering the significant role of the topological defects (especially magnetic strings in cosmology, here, we will investigate three dimensional horizonless magnetic solutions in the presence of two generalizations: massive gravity and nonlinear electromagnetic field. The effects of these two generalizations on properties of the solutions and their geometrical structure are investigated. The differences between de Sitter and anti de Sitter solutions are highlighted and conditions regarding the existence of phase transition in geometrical structure of the solutions are studied.

  20. Life is three-dimensional, and it begins with molecules.

    Directory of Open Access Journals (Sweden)

    Philip E Bourne

    2017-03-01

    Full Text Available The iconic image of the DNA double helix embodies the central role that three-dimensional structures play in understanding biological processes, which, in turn, impact health and well-being. Here, that role is explored through the eyes of one scientist, who has been lucky enough to have over 150 talented people pass through his laboratory. Each contributed to that understanding. What follows is a small fraction of their story, with an emphasis on basic research outcomes of importance to society at large.

  1. 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.

  2. 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.

  3. A Three-dimensional Topological Model of Ternary Phase Diagram

    International Nuclear Information System (INIS)

    Mu, Yingxue; Bao, Hong

    2017-01-01

    In order to obtain a visualization of the complex internal structure of ternary phase diagram, the paper realized a three-dimensional topology model of ternary phase diagram with the designed data structure and improved algorithm, under the guidance of relevant theories of computer graphics. The purpose of the model is mainly to analyze the relationship between each phase region of a ternary phase diagram. The model not only obtain isothermal section graph at any temperature, but also extract a particular phase region in which users are interested. (paper)

  4. Strongly interacting atom lasers in three-dimensional optical lattices.

    Science.gov (United States)

    Hen, Itay; Rigol, Marcos

    2010-10-29

    We show that the dynamical melting of a Mott insulator in a three-dimensional lattice leads to condensation at nonzero momenta, a phenomenon that can be used to generate strongly interacting atom lasers in optical lattices. For infinite on-site repulsion, the case considered here, the momenta at which bosons condense are determined analytically and found to have a simple dependence on the hopping amplitudes. The occupation of the condensates is shown to scale linearly with the total number of atoms in the initial Mott insulator. Our results are obtained by using a Gutzwiller-type mean-field approach, gauged against exact-diagonalization solutions of small systems.

  5. On a Three Dimensional Vision Based Collision Avoidance Model

    Science.gov (United States)

    Parzani, Céline; Filbet, Francis

    2017-08-01

    This paper presents a three dimensional collision avoidance approach for aerial vehicles inspired by coordinated behaviors in biological groups. The proposed strategy aims to enable a group of vehicles to converge to a common destination point avoiding collisions with each other and with moving obstacles in their environment. The interaction rules lead the agents to adapt their velocity vectors through a modification of the relative bearing angle and the relative elevation. Moreover the model satisfies the limited field of view constraints resulting from individual perception sensitivity. From the proposed individual based model, a mean-field kinetic model is derived. Simulations are performed to show the effectiveness of the proposed model.

  6. Analysis and visualization of complex unsteady three-dimensional flows

    Science.gov (United States)

    Van Dalsem, William R.; Buning, Pieter G.; Dougherty, F. Carroll; Smith, Merritt H.

    1989-01-01

    Flow field animation is the natural choice as a tool in the analysis of the numerical simulations of complex unsteady three-dimensional flows. The PLOT4D extension of the widely used PLOT3D code to allow the interactive animation of a broad range of flow variables was developed and is presented. To allow direct comparison with unsteady experimental smoke and dye flow visualization, the code STREAKER was developed to produce time accurate streaklines. Considerations regarding the development of PLOT4D and STREAKER, and example results are presented.

  7. Three-dimensional nonlinear waves under spatial confinement

    OpenAIRE

    Azhand, Arash

    2016-01-01

    The aim of my thesis is to study the evolution of scroll waves under spatial confinement both experimentally as well as numerically. Scroll waves represent three-dimensional (3D) analogs of spiral waves. In the simplest case, the central axis around which a scroll wave rotates is a straight line. The line is named the filament of the scroll wave, and each infinitesimal cross-section represents the core of a spiral wave. Two specific types of scroll waves are considered: (1) Straight scroll wa...

  8. Application of data mining in three-dimensional space time reactor model

    International Nuclear Information System (INIS)

    Jiang Botao; Zhao Fuyu

    2011-01-01

    A high-fidelity three-dimensional space time nodal method has been developed to simulate the dynamics of the reactor core for real time simulation. This three-dimensional reactor core mathematical model can be composed of six sub-models, neutron kinetics model, cay heat model, fuel conduction model, thermal hydraulics model, lower plenum model, and core flow distribution model. During simulation of each sub-model some operation data will be produced and lots of valuable, important information reflecting the reactor core operation status could be hidden in, so how to discovery these information becomes the primary mission people concern. Under this background, data mining (DM) is just created and developed to solve this problem, no matter what engineering aspects or business fields. Generally speaking, data mining is a process of finding some useful and interested information from huge data pool. Support Vector Machine (SVM) is a new technique of data mining appeared in recent years, and SVR is a transformed method of SVM which is applied in regression cases. This paper presents only two significant sub-models of three-dimensional reactor core mathematical model, the nodal space time neutron kinetics model and the thermal hydraulics model, based on which the neutron flux and enthalpy distributions of the core are obtained by solving the three-dimensional nodal space time kinetics equations and energy equations for both single and two-phase flows respectively. Moreover, it describes that the three-dimensional reactor core model can also be used to calculate and determine the reactivity effects of the moderator temperature, boron concentration, fuel temperature, coolant void, xenon worth, samarium worth, control element positions (CEAs) and core burnup status. Besides these, the main mathematic theory of SVR is introduced briefly next, on the basis of which SVR is applied to dealing with the data generated by two sample calculation, rod ejection transient and axial

  9. Magnetic properties of three-dimensional Hubbard-sigma model

    International Nuclear Information System (INIS)

    Yamamoto, Hisashi; Ichinose, Ikuo; Tatara, Gen; Matsui, Tetsuo.

    1989-11-01

    It is broadly viewed that the magnetism may play an important role in the high-T c superconductivity in the lamellar CuO 2 materials. In this paper, based on a Hubbard-inspired CP 1 or S 2 nonlinear σ model, we give a quantitative study of some magnetic properties in and around the Neel ordered state of three-dimensional quantum antiferromagnets such as La 2 CuO 4 with and without small hole doping. Our model is a (3+1) dimensional effective field theory describing the low energy spin dynamics of a three-dimensional Hubbard model with a very weak interlayer coupling. The effect of hole dynamics is taken into account in the leading approximation by substituting the CP 1 coupling with an 'effective' one determined by the concentration and the one-loop correction of hole fermions. A stationary-phase equation for the one-loop effective potential of S 2 model is analyzed numerically. The behavior of Neel temperature, magnetization (long range Neel order), spin correlation length, etc as functions of anisotropic parameter, temperature, hole concentrations, etc are investigated in detail. A phase diagram is also supported by the renormlization group analysis. The results show that our anisotropic field theory model with certain values of parameters could give a reasonably well description of the magnetic properties indicated by some experiments on pure and doped La 2 CuO 4 . (author)

  10. Three-dimensional structure of the γ-secretase complex

    International Nuclear Information System (INIS)

    Ogura, Toshihiko; Mio, Kazuhiro; Hayashi, Ikuo; Miyashita, Hiroyuki; Fukuda, Rie; Kopan, Raphael; Kodama, Tatsuhiko; Hamakubo, Takao; Iwastubo, Takeshi; Tomita, Taisuke; Sato, Chikara

    2006-01-01

    γ-Secretase belongs to an atypical class of aspartic proteases that hydrolyzes peptide bonds within the transmembrane domain of substrates, including amyloid-β precursor protein and Notch. γ-Secretase is comprised of presenilin, nicastrin, APH-1, and PEN-2 which form a large multimeric membrane protein complex, the three-dimensional structure of which is unknown. To gain insight into the structure of this complex enzyme, we purified functional γ-secretase complex reconstituted in Sf9 cells and analyzed it using negative stain electron microscopy and 3D reconstruction techniques. Analysis of 2341 negatively stained particle images resulted in the three-dimensional representation of γ-secretase at a resolution of 48 A. The structure occupies a volume of 560 x 320 x 240 A and resembles a flat heart comprised of two oppositely faced, dimpled domains. A low density space containing multiple pores resides between the domains. Some of the dimples in the putative transmembrane region may house the catalytic site. The large dimensions are consistent with the observation that γ-secretase activity resides within a high molecular weight complex

  11. Three-dimensional flows in a transonic compressor rotor

    Science.gov (United States)

    Reid, Lonnie; Celestina, Mark L.; Dewitt, Kenneth; Keith, Theo

    1991-01-01

    This study involves an experimental and numerical investigation of the three-dimensional flows in a transonic compressor rotor. A variety of data which could be used, in a complementary fashion, to validate/calibrate the computational fluid dynamics turbomachinery code and improve understanding of the flow physics, were acquired. Detailed radial survey data which consisted of total pressure, total temperature, static pressure and flow angle were obtained at stations upstream and downstream of the rotor blade. Detailed velocity and turbulence profiles were obtained upstream of the rotor and used as the upstream boundary conditions for the numerical analysis. Calibrated flush-mounted hot film probes were used to measure wall shear stress on the hub and casing walls upstream of the rotor. The blade-to-blade shear-stress angle distributions were obtained at two axial locations on the rotor casing, using flush-mounted hot film probes. A numerical analysis conducted using a three-dimensional Navier-Stokes code was compared with the experimental results.

  12. Three-dimensional volumetric display by inclined-plane scanning

    Science.gov (United States)

    Miyazaki, Daisuke; Eto, Takuma; Nishimura, Yasuhiro; Matsushita, Kenji

    2003-05-01

    A volumetric display system based on three-dimensional (3-D) scanning that uses an inclined two-dimensional (2-D) image is described. In the volumetric display system a 2-D display unit is placed obliquely in an imaging system into which a rotating mirror is inserted. When the mirror is rotated, the inclined 2-D image is moved laterally. A locus of the moving image can be observed by persistence of vision as a result of the high-speed rotation of the mirror. Inclined cross-sectional images of an object are displayed on the display unit in accordance with the position of the image plane to observe a 3-D image of the object by persistence of vision. Three-dimensional images formed by this display system satisfy all the criteria for stereoscopic vision. We constructed the volumetric display systems using a galvanometer mirror and a vector-scan display unit. In addition, we constructed a real-time 3-D measurement system based on a light section method. Measured 3-D images can be reconstructed in the 3-D display system in real time.

  13. Three-dimensional MRI with independent slab excitation and encoding.

    Science.gov (United States)

    Eissa, Amir; Wilman, Alan H

    2012-02-01

    Three-dimensional MRI is typically performed with the same orientation for radiofrequency slab excitation and slab select phase encoding. We introduce independent slab excitation and encoding to create a new degree of freedom in three-dimensional MRI, which is the angular relationship between the prescribed excitation volume and the voxel encoding grid. By separating the directions of slab excitation and slab phase encoding, the independent slab excitation and encoding method allows choice of optimal voxel orientation, while maintaining volume excitation based on anatomic landmarks. The method requires simple pulse sequence modifications and uses standard image reconstruction followed by removal of aliasing and image reformatting. The independent slab excitation and encoding method enables arbitrary oblique angle imaging using fixed voxel encoding gradients to maintain similar eddy current, concomitant field, or magnetic dipole effects independent of the oblique angle of excitation. We apply independent slab excitation and encoding to phase and susceptibility-weighted imaging using fixed voxel encoding aligned with the main magnetic field to demonstrate its value in both standardizing and improving image contrast, when using arbitrary oblique imaging volumes. Copyright © 2011 Wiley Periodicals, Inc.

  14. CFD three dimensional wake analysis in complex terrain

    Science.gov (United States)

    Castellani, F.; Astolfi, D.; Terzi, L.

    2017-11-01

    Even if wind energy technology is nowadays fully developed, the use of wind energy in very complex terrain is still challenging. In particular, it is challenging to characterize the combination effects of wind ow over complex terrain and wake interactions between nearby turbines and this has a practical relevance too, for the perspective of mitigating anomalous vibrations and loads as well improving the farm efficiency. In this work, a very complex terrain site has been analyzed through a Reynolds-averaged CFD (Computational Fluid Dynamics) numerical wind field model; in the simulation the inuence of wakes has been included through the Actuator Disk (AD) approach. In particular, the upstream turbine of a cluster of 4 wind turbines having 2.3 MW of rated power is studied. The objective of this study is investigating the full three-dimensional wind field and the impact of three-dimensionality on the evolution of the waked area between nearby turbines. A post-processing method of the output of the CFD simulation is developed and this allows to estimate the wake lateral deviation and the wake width. The reliability of the numerical approach is inspired by and crosschecked through the analysis of the operational SCADA (Supervisory Control and Data Acquisition) data of the cluster of interest.

  15. Three-dimensional nanoscale imaging by plasmonic Brownian microscopy

    Science.gov (United States)

    Labno, Anna; Gladden, Christopher; Kim, Jeongmin; Lu, Dylan; Yin, Xiaobo; Wang, Yuan; Liu, Zhaowei; Zhang, Xiang

    2017-12-01

    Three-dimensional (3D) imaging at the nanoscale is a key to understanding of nanomaterials and complex systems. While scanning probe microscopy (SPM) has been the workhorse of nanoscale metrology, its slow scanning speed by a single probe tip can limit the application of SPM to wide-field imaging of 3D complex nanostructures. Both electron microscopy and optical tomography allow 3D imaging, but are limited to the use in vacuum environment due to electron scattering and to optical resolution in micron scales, respectively. Here we demonstrate plasmonic Brownian microscopy (PBM) as a way to improve the imaging speed of SPM. Unlike photonic force microscopy where a single trapped particle is used for a serial scanning, PBM utilizes a massive number of plasmonic nanoparticles (NPs) under Brownian diffusion in solution to scan in parallel around the unlabeled sample object. The motion of NPs under an evanescent field is three-dimensionally localized to reconstruct the super-resolution topology of 3D dielectric objects. Our method allows high throughput imaging of complex 3D structures over a large field of view, even with internal structures such as cavities that cannot be accessed by conventional mechanical tips in SPM.

  16. Dynamic masquerade with morphing three-dimensional skin in cuttlefish.

    Science.gov (United States)

    Panetta, Deanna; Buresch, Kendra; Hanlon, Roger T

    2017-03-01

    Masquerade is a defence tactic in which a prey resembles an inedible or inanimate object thus causing predators to misclassify it. Most masquerade colour patterns are static although some species adopt postures or behaviours to enhance the effect. Dynamic masquerade in which the colour pattern can be changed is rare. Here we report a two-step sensory process that enables an additional novel capability known only in cuttlefish and octopus: morphing three-dimensional physical skin texture that further enhances the optical illusions created by coloured skin patterns. Our experimental design incorporated sequential sensory processes: addition of a three-dimensional rock to the testing arena, which attracted the cuttlefish to settle next to it; then visual processing by the cuttlefish of physical textures on the rock to guide expression of the skin papillae, which can range from fully relaxed (smooth skin) to fully expressed (bumpy skin). When a uniformly white smooth rock was presented, cuttlefish moved to the rock and deployed a uniform body pattern with mostly smooth skin. When a rock with small-scale fragments of contrasting shells was presented, the cuttlefish deployed mottled body patterns with strong papillae expression. These robust and reversible responses indicate a sophisticated visual sensorimotor system for dynamic masquerade. © 2017 The Author(s).

  17. The Bio Bay Game: Three-Dimensional Learning of Biomagnification.

    Science.gov (United States)

    Jasti, Chandana; Lauren, Hillary; Wallon, Robert C; Hug, Barbara

    2016-01-01

    Pressing concerns about sustainability and the state of the environment amplify the need to teach students about the connections between ecosystem health, toxicology, and human health. Additionally, the Next Generation Science Standards call for three-dimensional science learning, which integrates disciplinary core ideas, scientific practices, and crosscutting concepts. The Bio Bay Game is a way to teach students about the biomagnification of toxicants across trophic levels while engaging them in three-dimensional learning. In the game, the class models the biomagnification of mercury in a simple aquatic food chain as they play the roles of anchovies, tuna, and humans. While playing, the class generates data, which they analyze after the game to graphically visualize the buildup of toxicants. Students also read and discuss two articles that draw connections to a real-world case. The activity ends with students applying their understanding to evaluate the game as a model of biomagnification. Throughout the activity, students practice modeling and data analysis and engage with the crosscutting concepts of patterns and cause and effect to develop an understanding of core ideas about the connections between humans and the environment.

  18. Microfluidic tactile sensors for three-dimensional contact force measurements.

    Science.gov (United States)

    Nie, Baoqing; Li, Ruya; Brandt, James D; Pan, Tingrui

    2014-11-21

    A microfluidic tactile sensing device has been first reported for three-dimensional contact force measurement utilizing the microfluidic interfacial capacitive sensing (MICS) principle. Consisting of common and differential microfluidic sensing elements and topologically micro-textured surfaces, the microfluidic sensing devices are intended not only to resolve normal mechanical loads but also to measure forces tangent to the surface upon contact. In response to normal or shear loads, the membrane surface deforms the underlying sensing elements uniformly or differentially. The corresponding variation in interfacial capacitance can be detected from each sensing unit, from which the direction and magnitude of the original load can be determined. Benefiting from the highly sensitive and adaptive MICS principle, the microfluidic sensor is capable of detecting normal forces with a device sensitivity of 29.8 nF N(-1) in a 7 mm × 7 mm × 0.52 mm package, which is at least a thousand times higher than its solid-state counterparts to our best knowledge. In addition, the microfluidic sensing elements enable facilitated relaxation response/time in the millisecond range (up to 12 ms). To demonstrate the utility and flexibility of the three-dimensional microfluidic sensor, it has been successfully configured into a fingertip-amounted setting for continuous tracing of the fingertip movement and contact force measurement.

  19. THREE-DIMENSIONAL GENUS TOPOLOGY OF LUMINOUS RED GALAXIES

    International Nuclear Information System (INIS)

    Gott, J. Richard; Choi, Yun-Young; Park, Changbom; Kim, Juhan

    2009-01-01

    We measure the three-dimensional genus topology of large-scale structure using luminous red galaxies (LRGs) in the Sloan Digital Sky Survey and find it consistent with the Gaussian random phase initial conditions expected from the simplest scenarios of inflation. This studies three-dimensional topology on the largest scales ever obtained. The topology is spongelike. We measure topology in two volume-limited samples: a dense shallow sample studied with smoothing length of 21 h -1 Mpc, and a sparse deep sample studied with a smoothing length of 34 h -1 Mpc. The amplitude of the genus curve is measured with 4% uncertainty. Small distortions in the genus curve expected from nonlinear biasing and gravitational effects are well explained (to about 1σ accuracy) by N-body simulations using a subhalo-finding technique to locate LRGs. This suggests that the formation of LRGs is a clean problem that can be modeled well without any free-fitting parameters. This bodes well for using LRGs to measure the characteristic scales such as the baryon oscillation scale in future deep redshift surveys.

  20. Three-dimensional wave patterns in falling films

    Science.gov (United States)

    Scheid, Benoit; Ruyer-Quil, Christian; Manneville, Paul

    2005-11-01

    A large number of studies have been devoted to the modeling of film flows down inclined planes since the pioneering work of Kapitza & Kapitza (1949). Ruyer-Quil & Manneville (2000,2002) have extended the Shkadov formulation (1967) applying weighting residual techniques and expanding the flow field over a complete basis of polynomial functions. Inspired from a Pad'e-like approximant technique initially proposed by Ooshida (1999), a refined model is now formulated which also includes second-order inertia effects arising from the deviation of the streamwise velocity profile from its parabolic shape. The stability of two- dimensional traveling waves against three-dimensional perturbations is investigated using this model. The secondary instability is found to be not really selective which explains the widespread presence of the synchronous instability observed in the experiments by Liu et al. (1995), though theory predicts in most cases a subharmonic scenario. Three-dimensional wave patterns are next computed assuming periodic boundary conditions. Transition from 2D to 3D flows is shown to be strongly dependent on initial conditions. The herringbone patterns, the synchronously deformed fronts, the oblique and the V-shape solitary waves observed in various experimental data (Liu et al. 1995; Park & Nosoko 2003; Alekseenko et al. 1994) are reliably recovered.

  1. Creation of three-dimensional craniofacial standards from CBCT images

    Science.gov (United States)

    Subramanyan, Krishna; Palomo, Martin; Hans, Mark

    2006-03-01

    Low-dose three-dimensional Cone Beam Computed Tomography (CBCT) is becoming increasingly popular in the clinical practice of dental medicine. Two-dimensional Bolton Standards of dentofacial development are routinely used to identify deviations from normal craniofacial anatomy. With the advent of CBCT three dimensional imaging, we propose a set of methods to extend these 2D Bolton Standards to anatomically correct surface based 3D standards to allow analysis of morphometric changes seen in craniofacial complex. To create 3D surface standards, we have implemented series of steps. 1) Converting bi-plane 2D tracings into set of splines 2) Converting the 2D splines curves from bi-plane projection into 3D space curves 3) Creating labeled template of facial and skeletal shapes and 4) Creating 3D average surface Bolton standards. We have used datasets from patients scanned with Hitachi MercuRay CBCT scanner providing high resolution and isotropic CT volume images, digitized Bolton Standards from age 3 to 18 years of lateral and frontal male, female and average tracings and converted them into facial and skeletal 3D space curves. This new 3D standard will help in assessing shape variations due to aging in young population and provide reference to correct facial anomalies in dental medicine.

  2. A vein display system based on three-dimensional reconstruction

    Science.gov (United States)

    Wang, Danting; Zhou, Ya; Hu, Xiaoming; Wu, Zhaoguo; Dai, Xiaobin

    2014-10-01

    Venipuncture is the most common way of all invasive medical procedures. A vein display system can make vein access easier by capturing the vein information and projecting a visible vein image onto the skin, which is correctly aligned with the subject's vein. The existing systems achieve correct alignment by the design of coaxial structure. Such a structure causes complex optical and mechanical design and big physical dimensions inevitably. In this paper, we design a stereovision- based vein display system, which consists of a pair of cameras, a DLP projector and a near-infrared light source. We recover the three-dimensional venous structure from image pair acquired from two near-infrared cameras. Then the vein image from the viewpoint of projector is generated from the three-dimensional venous structure and projected exactly onto skin by the DLP projector. Since the stereo cameras get the depth information of vessels, the system can make sure the alignment of projected veins and the real veins without a coaxial structure. The experiment results prove that we propose a feasible solution for a portable and low-cost vein display device.

  3. Three dimensional dynamics of a flexible Motorised Momentum Exchange Tether

    Science.gov (United States)

    Ismail, N. A.; Cartmell, M. P.

    2016-03-01

    This paper presents a new flexural model for the three dimensional dynamics of the Motorised Momentum Exchange Tether (MMET) concept. This study has uncovered the relationships between planar and nonplanar motions, and the effect of the coupling between these two parameters on pragmatic circular and elliptical orbits. The tether sub-spans are modelled as stiffened strings governed by partial differential equations of motion, with specific boundary conditions. The tether sub-spans are flexible and elastic, thereby allowing three dimensional displacements. The boundary conditions lead to a specific frequency equation and the eigenvalues from this provide the natural frequencies of the orbiting flexible motorised tether when static, accelerating in monotonic spin, and at terminal angular velocity. A rotation transformation matrix has been utilised to get the position vectors of the system's components in an assumed inertial frame. Spatio-temporal coordinates are transformed to modal coordinates before applying Lagrange's equations, and pre-selected linear modes are included to generate the equations of motion. The equations of motion contain inertial nonlinearities which are essentially of cubic order, and these show the potential for intricate intermodal coupling effects. A simulation of planar and non-planar motions has been undertaken and the differences in the modal responses, for both motions, and between the rigid body and flexible models are highlighted and discussed.

  4. Horizontal biases in rats’ use of three-dimensional space

    Science.gov (United States)

    Jovalekic, Aleksandar; Hayman, Robin; Becares, Natalia; Reid, Harry; Thomas, George; Wilson, Jonathan; Jeffery, Kate

    2011-01-01

    Rodent spatial cognition studies allow links to be made between neural and behavioural phenomena, and much is now known about the encoding and use of horizontal space. However, the real world is three dimensional, providing cognitive challenges that have yet to be explored. Motivated by neural findings suggesting weaker encoding of vertical than horizontal space, we examined whether rats show a similar behavioural anisotropy when distributing their time freely between vertical and horizontal movements. We found that in two- or three-dimensional environments with a vertical dimension, rats showed a prioritization of horizontal over vertical movements in both foraging and detour tasks. In the foraging tasks, the animals executed more horizontal than vertical movements and adopted a “layer strategy” in which food was collected from one horizontal level before moving to the next. In the detour tasks, rats preferred the routes that allowed them to execute the horizontal leg first. We suggest three possible reasons for this behavioural bias. First, as suggested by Grobety and Schenk [5], it allows minimisation of energy expenditure, inasmuch as costly vertical movements are minimised. Second, it may be a manifestation of the temporal discounting of effort, in which animals value delayed effort as less costly than immediate effort. Finally, it may be that at the neural level rats encode the vertical dimension less precisely, and thus prefer to bias their movements in the more accurately encoded horizontal dimension. We suggest that all three factors are related, and all play a part. PMID:21419172

  5. Three-dimensional modeler for animated images display system

    International Nuclear Information System (INIS)

    Boubekeur, Rania

    1987-01-01

    The mv3d software allows the modeling and display of three dimensional objects in interpretative mode with animation possibility in real time. This system is intended for a graphical extension of a FORTH interpreter (implemented by CEA/IRDI/D.LETI/DEIN) in order to control a specific hardware (3.D card designed and implemented by DEIN) allowing the generation of three dimensional objects. The object description is carried out with a specific graphical language integrated in the FORTH interpreter. Objects are modeled using elementary solids called basic forms (cube, cone, cylinder...) assembled with classical geometric transformations (rotation, translation and scaling). These basic forms are approximated by plane polygonal facets further divided in triangles. Coordinates of the summits of triangles constitute the geometrical data. These are sent to the 3.D. card for processing and display. Performed processing are: geometrical transformations on display, hidden surface elimination, shading and clipping. The mv3d software is not an entire modeler but a simple, modular and extensible tool, to which other specific functions may be easily added such as: robots motion, collisions... (author) [fr

  6. Characterization of an Actively Controlled Three-Dimensional Turret Wake

    Science.gov (United States)

    Shea, Patrick; Glauser, Mark

    2012-11-01

    Three-dimensional turrets are commonly used for housing optical systems on airborne platforms. As bluff bodies, these geometries generate highly turbulent wakes that decrease the performance of the optical systems and the aircraft. The current experimental study looked to use dynamic suction in both open and closed-loop control configurations to actively control the turret wake. The flow field was characterized using dynamic pressure and stereoscopic PIV measurements in the wake of the turret. Results showed that the suction system was able to manipulate the wake region of the turret and could alter not only the spatial structure of the wake, but also the temporal behavior of the wake flow field. Closed-loop, feedback control techniques were used to determine a more optimal control input for the flow control. Similar control effects were seen for both the steady open-loop control case and the closed-loop feedback control configuration with a 45% reduction in the suction levels when comparing the closed-loop to the open-loop case. These results provide unique information regarding the development of the baseline three-dimensional wake and the wake with three different active flow control configurations.

  7. Three dimensional birefringence control using nanoparticles for uniaxially oriented films

    Science.gov (United States)

    Takatoh, Kohki; Goda, Kazuya; Akimoto, Mitsuhiro; Abo, Tomohiro

    2017-07-01

    In uniaxially stretched films, the refractive indices perpendicular to the stretching direction have the same value, and so, the out-of-plane birefringence is half that of the in-plane birefringence. This means that these values cannot be controlled independently in uniaxially stretched films. The same relationship was previously observed when needle-shaped nanoparticles were added to uniaxially stretched films. This paper presents a method to achieve the three-dimensional birefringence control of uniaxially stretched films. When we added plate-shaped smectite nanoparticles to uniaxially stretched films, different relationships were observed for the in- and out-of-plane birefringence. The magnitude of the out-of-plane birefringence increased more than would be expected according to the usual relationship. According to our results, uniaxially stretched films with no out-of-plane birefringence and negative in-plane birefringence can be formed by adding smectite nanoparticles to polymer films with negative in-plane birefringence. Using our method, the three-dimensional birefringence of uniaxial polymers can be controlled, and the possibility of the uniaxial films could be drastically extended.

  8. Modular transportation system with a three dimensional routeing

    Directory of Open Access Journals (Sweden)

    Löffler Christoph

    2015-12-01

    Full Text Available In intra-enterprise logistics and automation of manufacturing processes general a rising productivity by high flexibility is required. Existing transportation systems exclusively use two-dimensional track sections, because they can be served with standard drives. Because of these simple structures the transport speed is limited and thereby also the throughput. In this paper now a modular transportation system is presented which could reach higher speeds with a direct drive and the use of centrifugal force compensating curves. Simultaneously the system also can change the altitude. All this succeeds with the integration of three-dimensional track sections. Therefore a two piped guiding system with a long stator linear motor was designed. To combine the linear motor with the three dimensional track special stator elements were developed which allow a bending of the stator to follow the route course. The current work deals with the implementation of a mechanical passive switch, which is operated by the electromagnetic forces of the linear motor. So no additional mechanical actors or a separate electromagnetic system are necessary.

  9. Stability analysis of non-axisymmetric three-dimensional finite ...

    Indian Academy of Sciences (India)

    Author Affiliations. Smitadhi Ganguly1 A Nandi2 S Neogy2. Department of Mechanical Engineering, Hooghly Engineering and Technology College, Hooghly 712 103, India; Department of Mechanical Engineering, Jadavpur University, Kolkata 700 032, India ...

  10. Construction of a Three-Dimensional in vitro skin model on polycaprolactone fibers.

    Science.gov (United States)

    Liu, Qi; Zhang, Ru-Zhi; Xu, Bin

    2017-05-16

    To observe the morphological characteristics and the biological properties of human epidermal cells when cultured at an air-liquid interface in polycaprolactone (PCL) fibers as a three-dimensional scaffold for tissue engineering. In this study, the melanocytes and keratinocytes were obtained from human scalp skin, seeded onto a PCL film, and cocultured for 2 weeks to construct a three-dimensional (3D) skin model. The cells were then characterized by hematoxylin and eosin (H&E) staining, by immunohistochemical staining with antibodies to cytokeratin 15 (CK15), Ki-67, CD34, CD200 and HMB45 and by transmission electron microscopy. Keratinocytes and melanocytes grew well in the co-culture system. Hematoxylin and eosin staining revealed that the cells adhered to the PCLfiber scaffold well, the keratinocyte layer became a multilayered concentric structure and the surface became distinctly keratinized at the air-liquid interface. Immunohistochemical analyses exhibited a scattered distribution of cells expressing CK15, CD34, CD200, Ki-67 and/or HMB45. Transmission electron microscopy revealed that the keratinocytes contained a number of keratin fibrils and membrane-coated granules. The PCL scaffold has excellent adhesiveness and biocompatibility with human epidermal cells, and is suitable for constructing 3D skin models for tissue engineering in the future.

  11. Osteogenic differentiation of mesenchymal stromal cells in two-dimensional and three-dimensional cultures without animal serum.

    Science.gov (United States)

    Castrén, Eeva; Sillat, Tarvo; Oja, Sofia; Noro, Ariel; Laitinen, Anita; Konttinen, Yrjö T; Lehenkari, Petri; Hukkanen, Mika; Korhonen, Matti

    2015-09-07

    Bone marrow-derived mesenchymal stromal cells (MSCs) have been intensely studied for the purpose of developing solutions for clinical tissue engineering. Autologous MSCs can potentially be used to replace tissue defects, but the procedure also carries risks such as immunization and xenogeneic infection. Replacement of the commonly used fetal calf serum (FCS) with human platelet lysate and plasma (PLP) to support cell growth may reduce some of these risks. Altered media could, however, influence stem cell differentiation and we address this experimentally. We examined human MSC differentiation into the osteoblast lineage using in vitro two- and three-dimensional cultures with PLP or FCS as cell culture medium supplements. Differentiation was followed by quantitative polymerase chain reaction, and alkaline phosphatase activity, matrix formation and matrix calcium content were quantified. Three-dimensional culture, where human MSCs were grown on collagen sponges, markedly stimulated osteoblast differentiation; a fourfold increase in calcium deposition could be observed in both PLP and FCS groups. PLP-grown cells showed robust osteogenic differentiation both in two- and three-dimensional MSC cultures. The calcium content of the matrix in the two-dimensional PLP group at day 14 was 2.2-fold higher in comparison to the FCS group (p cultures, cellular proliferation appeared to decrease during later stages of differentiation, while in the FCS group the number of cells increased throughout the experiment. In three-dimensional experiments, the PLP and FCS groups behaved more congruently, except for the alkaline phosphatase activity and mRNA levels which were markedly increased by PLP. Human PLP was at least equal to FCS in supporting osteogenic differentiation of human MSCs in two- and three-dimensional conditions; however, proliferation was inferior. As PLP is free of animal components, and thus represents reduced risk for xenogeneic infection, its use for human MSC

  12. Three-dimensional S-wave tomography under Axial Seamount

    Science.gov (United States)

    Baillard, C.; Wilcock, W. S. D.; Arnulf, A. F.; Tolstoy, M.; Waldhauser, F.

    2017-12-01

    Axial Seamount is a submarine volcano located at the intersection of the Juande Fuca Ridge and the Cobb-Eickelberg hotspot 500 km off the coast of thenorthwestern United States. The seamount, which rises 1 km above the seafloor, ischaracterized by a shallow caldera that is elongated in the N-S direction, measure 8km by 3 km and sits on top of a 14 km by 3 km magma reservoir. Two eruptive eventsin 1998 and 2011 motivated the deployment in 2014 of a real time cabled observatorywithin the Axial caldera, as part of the Ocean Observatories Initiative (OOI).Theobservatory includes a network of seven seismometers that span the southern half ofthe caldera. Five months after the observatory came on-line in November 2014, thevolcano erupted on April 24, 2015. Well over 100,000 events were located in thevicinity of the caldera, delineating an outward dipping ring fault that extends fromnear the surface to the magma body at 2 km depth and which accommodatesinflation and deflation of the volcano.The initial earthquake locations have beenobtained with a one-dimensional velocity model but the travel time residuals suggeststrong heterogeneities. A three-dimensional P-wave velocity model, obtained bycombining multichannel and ocean bottom seismometer refraction data, is being usedto refine locations but the three-dimensional S-wave structure is presently unknown.In most mid-ocean ridge settings, the distribution of earthquakes is not conducive forjoint inversions for S-wave velocity and hypocentral parameters because there are fewcrossing ray paths but at Axial the presence of a ring fault that is seismically active atall depths on both the east and west side of the caldera, provides a reasonablegeometry for such efforts. We will present the results of joint inversions that assumethe existing three-dimensional P wave velocity model and solve for VP/VS structure andhypocentral parameters using LOTOS, an algorithm that solves the forward problemusing ray bending.The resulting model

  13. Visual Interpretation with Three-Dimensional Annotations (VITA): three-dimensional image interpretation tool for radiological reporting.

    Science.gov (United States)

    Roy, Sharmili; Brown, Michael S; Shih, George L

    2014-02-01

    This paper introduces a software framework called Visual Interpretation with Three-Dimensional Annotations (VITA) that is able to automatically generate three-dimensional (3D) visual summaries based on radiological annotations made during routine exam reporting. VITA summaries are in the form of rotating 3D volumes where radiological annotations are highlighted to place important clinical observations into a 3D context. The rendered volume is produced as a Digital Imaging and Communications in Medicine (DICOM) object and is automatically added to the study for archival in Picture Archiving and Communication System (PACS). In addition, a video summary (e.g., MPEG4) can be generated for sharing with patients and for situations where DICOM viewers are not readily available to referring physicians. The current version of VITA is compatible with ClearCanvas; however, VITA can work with any PACS workstation that has a structured annotation implementation (e.g., Extendible Markup Language, Health Level 7, Annotation and Image Markup) and is able to seamlessly integrate into the existing reporting workflow. In a survey with referring physicians, the vast majority strongly agreed that 3D visual summaries improve the communication of the radiologists' reports and aid communication with patients.

  14. Phase Diagrams of Three-Dimensional Anderson and Quantum Percolation Models Using Deep Three-Dimensional Convolutional Neural Network

    Science.gov (United States)

    Mano, Tomohiro; Ohtsuki, Tomi

    2017-11-01

    The three-dimensional Anderson model is a well-studied model of disordered electron systems that shows the delocalization-localization transition. As in our previous papers on two- and three-dimensional (2D, 3D) quantum phase transitions [https://doi.org/10.7566/JPSJ.85.123706" xlink:type="simple">J. Phys. Soc. Jpn. 85, 123706 (2016), https://doi.org/10.7566/JPSJ.86.044708" xlink:type="simple">86, 044708 (2017)], we used an image recognition algorithm based on a multilayered convolutional neural network. However, in contrast to previous papers in which 2D image recognition was used, we applied 3D image recognition to analyze entire 3D wave functions. We show that a full phase diagram of the disorder-energy plane is obtained once the 3D convolutional neural network has been trained at the band center. We further demonstrate that the full phase diagram for 3D quantum bond and site percolations can be drawn by training the 3D Anderson model at the band center.

  15. Three-Dimensional, Transgenic Cell Models to Quantify Space Genotoxic Effects

    Science.gov (United States)

    Gonda, S. R.; Sognier, M. A.; Wu, H.; Pingerelli, P. L.; Glickman, B. W.; Dawson, David L. (Technical Monitor)

    1999-01-01

    The space environment contains radiation and chemical agents known to be mutagenic and carcinogenic to humans. Additionally, microgravity is a complicating factor that may modify or synergize induced genotoxic effects. Most in vitro models fail to use human cells (making risk extrapolation to humans more difficult), overlook the dynamic effect of tissue intercellular interactions on genotoxic damage, and lack the sensitivity required to measure low-dose effects. Currently a need exists for a model test system that simulates cellular interactions present in tissue, and can be used to quantify genotoxic damage induced by low levels of radiation and chemicals, and extrapolate assessed risk to humans. A state-of-the-art, three-dimensional, multicellular tissue equivalent cell culture model will be presented. It consists of mammalian cells genetically engineered to contain multiple copies of defined target genes for genotoxic assessment,. NASA-designed bioreactors were used to coculture mammalian cells into spheroids, The cells used were human mammary epithelial cells (H184135) and Stratagene's (Austin, Texas) Big Blue(TM) Rat 2 lambda fibroblasts. The fibroblasts were genetically engineered to contain -a high-density target gene for mutagenesis (60 copies of lacl/LacZ per cell). Tissue equivalent spheroids were routinely produced by inoculation of 2 to 7 X 10(exp 5) fibroblasts with Cytodex 3 beads (150 micrometers in diameter). at a 20:1 cell:bead ratio, into 50-ml HARV bioreactors (Synthecon, Inc.). Fibroblasts were cultured for 5 days, an equivalent number of epithelial cells added, and the fibroblast/epithelial cell coculture continued for 21 days. Three-dimensional spheroids with diameters ranging from 400 to 600 micrometers were obtained. Histological and immunohistochemical Characterization revealed i) both cell types present in the spheroids, with fibroblasts located primarily in the center, surrounded by epithelial cells; ii) synthesis of extracellular matrix

  16. Applications of three-dimensional printing technology in the cardiovascular field.

    Science.gov (United States)

    Shi, Di; Liu, Kai; Zhang, Xin; Liao, Hang; Chen, Xiaoping

    2015-10-01

    Three-dimensional (3-D) printing technology has rapidly developed in the last few decades. Meanwhile, the application of this technology has reached beyond the engineering field and expanded to almost all disciplines, including medicine. There has been much research on the medical applications of 3-D printing in neurosurgery, orthopedics, maxillofacial surgery, plastic surgery, tissue engineering, as well as other fields. Because of the complexity of the cardiovascular system, the application of this technology is limited and difficult, as compared to other disciplines, and thus there is much room for future development. Many of the difficulties associated with this technology must be overcome. Nonetheless, there is no doubt that 3-D printing technology will benefit patients with cardiovascular diseases in the near future.

  17. Three dimensional simulation for bayou choctaw strategic petroleum reserve (SPR).

    Energy Technology Data Exchange (ETDEWEB)

    Ehgartner, Brian L. (Sandia National Laboratories, Albuquerque, NM); Park, Byoung Yoon; Lee, Moo Yul

    2006-12-01

    Three dimensional finite element analyses were performed to evaluate the structural integrity of the caverns located at the Bayou Choctaw (BC) site which is considered a candidate for expansion. Fifteen active and nine abandoned caverns exist at BC, with a total cavern volume of some 164 MMB. A 3D model allowing control of each cavern individually was constructed because the location and depth of caverns and the date of excavation are irregular. The total cavern volume has practical interest, as this void space affects total creep closure in the BC salt mass. Operations including both cavern workover, where wellhead pressures are temporarily reduced to atmospheric, and cavern enlargement due to leaching during oil drawdowns that use water to displace the oil from the caverns, were modeled to account for as many as the five future oil drawdowns in the six SPR caverns. The impacts on cavern stability, underground creep closure, surface subsidence, infrastructure, and well integrity were quantified.

  18. Three-dimensional mechanical metamaterials with a twist.

    Science.gov (United States)

    Frenzel, Tobias; Kadic, Muamer; Wegener, Martin

    2017-11-24

    Rationally designed artificial materials enable mechanical properties that are inaccessible with ordinary materials. Pushing on an ordinary linearly elastic bar can cause it to be deformed in many ways. However, a twist, the counterpart of optical activity in the static case, is strictly zero. The unavailability of this degree of freedom hinders applications in terms of mode conversion and the realization of advanced mechanical designs using coordinate transformations. Here, we aim at realizing microstructured three-dimensional elastic chiral mechanical metamaterials that overcome this limitation. On overall millimeter-sized samples, we measure twists per axial strain exceeding 2°/%. Scaling up the number of unit cells for fixed sample dimensions, the twist is robust due to metamaterial stiffening, indicating a characteristic length scale and bringing the aforementioned applications into reach. Copyright © 2017, American Association for the Advancement of Science.

  19. Experimental three dimensional strain estimation from ultrasonic sectorial data.

    Science.gov (United States)

    Said, G; Basset, O; Mari, J M; Cachard, C; Brusseau, E; Vray, D

    2006-12-22

    Most of the studies devoted to elastography are focused on the estimation of the axial component of the strain. However when subjected to any load, whatever the direction, soft biological media deform in the three spatial dimensions. The aim of our work is to build a three dimensional strain mapping from data acquired with a 3D clinical sectorial probe. The estimation of radial strain is based on the estimation of local scaling factors. A method of cross-correlation of interpolated signals between adjacent radiofrequency lines was used to estimate the angular displacement and strain. For the sectorial strain estimation, the same displacement estimation technique has been implemented. The method has been tested on experimental data acquired on calibrated phantoms and compared to simulation.

  20. Automated three-dimensional reconstruction of the Caenorhabditis elegans germline.

    Science.gov (United States)

    Gopal, Sandeep; Boag, Peter; Pocock, Roger

    2017-12-15

    The Caenorhabditis elegans germline is widely used as a model to study stem cell development, chromosome dynamics and apoptosis. Major readouts of germline phenotypes such as cell counting and protein expression profiling are routinely analyzed manually and in a two-dimensional manner. The major disadvantages of the existing approaches are 1) they are time-consuming and laborious and 2) there is an inability to study the effects of genetic mutations in three dimensions. Here, we demonstrate a rapid, automated method for analyzing the three-dimensional distribution of proteins, germline nuclei and cytoskeletal structures in the C. elegans germline. Using this method, we have revealed previously unappreciated germline organization and cytoskeletal structures that will have a major impact on the characterization of germline phenotypes. To conclude, our new method dramatically enhances the efficiency and resolution of C. elegans germline analysis and may be applied to other cellular structures. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Three-dimensional morphology of the human embryonic brain

    Directory of Open Access Journals (Sweden)

    N. Shiraishi

    2015-09-01

    Full Text Available The morphogenesis of the cerebral vesicles and ventricles was visualized in 3D movies using images derived from human embryo specimens between Carnegie stage 13 and 23 from the Kyoto Collection. These images were acquired with a magnetic resonance microscope equipped with a 2.35-T superconducting magnet. Three-dimensional images using the same scale demonstrated brain development and growth effectively. The non-uniform thickness of the brain tissue, which may indicate brain differentiation, was visualized with thickness-based surface color mapping. A closer view was obtained of the unique and complicated differentiation of the rhombencephalon, especially with regard to the internal view and thickening of the brain tissue. The present data contribute to a better understanding of brain and cerebral ventricle development.

  2. Quantum Secure Direct Communication by Using Three-Dimensional Hyperentanglement

    International Nuclear Information System (INIS)

    Shi Jin; Gong Yanxiao; Xu Ping; Zhu Shining; Zhan Youbang

    2011-01-01

    We propose two schemes for realizing quantum secure direct communication (QSDC) by using a set of ordered two-photon three-dimensional hyperentangled states entangled in two degrees of freedom (DOFs) as quantum information channels. In the first scheme, the photons from Bob to Alice are transmitted only once. After insuring the security of the quantum channels, Bob encodes the secret message on his photons. Then Alice performs single-photon two-DOF Bell bases measurements on her photons. This scheme has better security than former QSDC protocols. In the second scheme, Bob transmits photons to Alice twice. After insuring the security of the quantum channels, Bob encodes the secret message on his photons. Then Alice performs two-photon Bell bases measurements on each DOF. The scheme has more information capacity than former QSDC protocols. (general)

  3. Three-dimensional MR imaging of the knee joint

    International Nuclear Information System (INIS)

    Niitsu, Mamoru

    1991-01-01

    The value of a three-dimensional (3D) imaging system was evaluated using a newly developed workstation. Fifteen knee joints with meniscal tears confirmed by arthroscopic examinations underwent 3D magnetic resonance (MR) imaging. These 3D data sets were processed into 3D display by multiplanar reformation (MPR) and the volume rendering technique, and the features of the meniscal tears were compared with those on conventional two-dimensional (2D) MR images. The 3D images with MPR provided higher detectability and more descriptive delineation of the meniscal tears than the 2D images. With its powerful image processing capacity, the workstation facilitated high-speed, high-quality 3D display and provided precise views of meniscal cleavages for the planning of surgical treatment. The independent processing system permitted efficient throughput of the MR data and eliminated wasteful filming processes. (author)

  4. Three-dimensional solution structure of Acanthamoeba profilin-I

    Science.gov (United States)

    1993-01-01

    We have determined a medium resolution three-dimensional solution structure of Acanthamoeba profilin-I by multidimensional nuclear magnetic resonance spectroscopy. This 13-kD actin binding protein consists of a five stranded antiparallel beta sheet flanked by NH2- and COOH-terminal helices on one face and by a third helix and a two stranded beta sheet on the other face. Data from actin-profilin cross- linking experiments and the localization of conserved residues between profilins in different phyla indicate that actin binding occurs on the molecular face occupied by the terminal helices. The other face of the molecule contains the residues that differ between Acanthamoeba profilins-I and II and may be important in determining the difference in polyphosphoinositide binding between these isoforms. This suggests that lipids and actin bind to different faces of the molecule. PMID:8397216

  5. Controlling Random Lasing with Three-Dimensional Plasmonic Nanorod Metamaterials.

    Science.gov (United States)

    Wang, Zhuoxian; Meng, Xiangeng; Choi, Seung Ho; Knitter, Sebastian; Kim, Young L; Cao, Hui; Shalaev, Vladimir M; Boltasseva, Alexandra

    2016-04-13

    Plasmonics has brought revolutionary advances to laser science by enabling deeply subwavelength nanolasers through surface plasmon amplification. However, the impact of plasmonics on other promising laser systems has so far remained elusive. Here, we present a class of random lasers enabled by three-dimensional plasmonic nanorod metamaterials. While dense metallic nanostructures are usually detrimental to laser performance due to absorption losses, here the lasing threshold keeps decreasing as the volume fraction of metal is increased up to ∼0.07. This is ∼460 times higher than the optimal volume fraction reported thus far. The laser supports spatially confined lasing modes and allows for efficient modulation of spectral profiles by simply tuning the polarization of the pump light. Full-field speckle-free imaging at micron-scales has been achieved by using plasmonic random lasers as the illumination sources. Our findings show that plasmonic metamaterials hold potential to enable intriguing coherent optical sources.

  6. Three-dimensional structure of brain tissue at submicrometer resolution

    Energy Technology Data Exchange (ETDEWEB)

    Saiga, Rino; Mizutani, Ryuta, E-mail: ryuta@tokai-u.jp [Department of Applied Biochemistry, Tokai University, Hiratsuka, Kanagawa 259-1292 (Japan); Inomoto, Chie; Takekoshi, Susumu; Nakamura, Naoya; Tsuboi, Akio; Osawa, Motoki [Tokai University School of Medicine, Isehara, Kanagawa 259-1193 (Japan); Arai, Makoto; Oshima, Kenichi; Itokawa, Masanari [Tokyo Metropolitan Institute of Medical Science, Setagaya, Tokyo 156-8506 (Japan); Uesugi, Kentaro; Takeuchi, Akihisa; Terada, Yasuko; Suzuki, Yoshio [Japan Synchrotron Radiation Research Institute (JASRI/SPring-8), Sayo, Hyogo 679-5198 (Japan)

    2016-01-28

    Biological objects are composed of submicrometer structures such as cells and organelles that are essential for their functions. Here, we report on three-dimensional X-ray visualization of cells and organelles at resolutions up to 100 nm by imaging microtomography (micro-CT) equipped with Fresnel zone plate optics. Human cerebral tissue, fruit fly cephalic ganglia, and Escherichia coli bacteria labeled with high atomic-number elements were embedded in epoxy resin and subjected to X-ray microtomography at the BL37XU and BL47XU beamlines of the SPring-8 synchrotron radiation facility. The obtained results indicated that soft tissue structures can be visualized with the imaging microtomography.

  7. Three-dimensional spatial grouping affects estimates of the illuminant.

    Science.gov (United States)

    Perkins, Kenneth R; Schirillo, James A

    2003-12-01

    The brightnesses (i.e., perceived luminance) of surfaces within a three-dimensional scene are contingent on both the luminances and the spatial arrangement of the surfaces. Observers viewed a CRT through a haploscope that presented simulated achromatic surfaces in three dimensions. They set a test patch to be approximately 33% more intense than a comparison patch to match the comparison patch in brightness, which is consistent with viewing a real scene with a simple lightning interpretation from which to estimate a different level of illumination in each depth plane. Randomly positioning each surface in either depth plane minimized any simple lighting interpretation, concomitantly reducing brightness differences to approximately 8.5%, although the immediate surrounds of the test and comparison patches continued to differ by a 5:1 luminance ratio.

  8. Three-dimensional theory for light-matter interaction

    DEFF Research Database (Denmark)

    Sørensen, Martin Westring; Sørensen, Anders Søndberg

    2008-01-01

    We present a full quantum mechanical three dimensional theory describing an electromagnetic field interacting with an ensemble of identical atoms. The theory is constructed such that it describes recent experiments on light-matter quantum interfaces, where the quantum fluctuations of light...... are mapped onto the atoms and back onto light. We show that the interaction of the light with the atoms may be separated into a mean effect of the ensemble and a deviation from the mean. The mean effect of the interaction effectively give rise to an index of refraction of the gas. We formally change...... to a dressed state picture, where the light modes are solutions to the diffraction problem, and develop a perturbative expansion in the fluctuations. The fluctuations are due to quantum fluctuations as well as the random positions of the atoms. In this perturbative expansion we show how the quantum...

  9. Visualising very large phylogenetic trees in three dimensional hyperbolic space

    Directory of Open Access Journals (Sweden)

    Liberles David A

    2004-04-01

    Full Text Available Abstract Background Common existing phylogenetic tree visualisation tools are not able to display readable trees with more than a few thousand nodes. These existing methodologies are based in two dimensional space. Results We introduce the idea of visualising phylogenetic trees in three dimensional hyperbolic space with the Walrus graph visualisation tool and have developed a conversion tool that enables the conversion of standard phylogenetic tree formats to Walrus' format. With Walrus, it becomes possible to visualise and navigate phylogenetic trees with more than 100,000 nodes. Conclusion Walrus enables desktop visualisation of very large phylogenetic trees in 3 dimensional hyperbolic space. This application is potentially useful for visualisation of the tree of life and for functional genomics derivatives, like The Adaptive Evolution Database (TAED.

  10. Inner mechanics of three-dimensional black holes.

    Science.gov (United States)

    Detournay, Stéphane

    2012-07-20

    We investigate properties of the inner horizons of certain black holes in higher-derivative three-dimensional gravity theories. We focus on Bañados-Teitelboim-Zanelli and spacelike warped anti-de Sitter black holes, as well as on asymptotically warped de Sitter solutions exhibiting both a cosmological and a black hole horizon. We verify that a first law is satisfied at the inner horizon, in agreement with the proposal of Castro and Rodriguez [arXiv:1204.1284]. We then show that, in topologically massive gravity, the product of the areas of the inner and outer horizons fails to be independent on the mass, and we trace this to the diffeomorphism anomaly of the theory.

  11. Three Dimensional Quantized Vortex Dynamics in Superfluid Helium

    Science.gov (United States)

    Meichle, David; Megson, Peter; Lathrop, Daniel

    2014-11-01

    Vorticity is constrained to line-like topological defects in quantum superfluids, such as liquid Helium below the Lambda transition temperature of 2.17 Kelvin. A tangle of vortices exists in a dissipative dynamical state called quantum turbulence, which has quantitative features distinct from classical turbulence. To study the vortex dynamics, we have invented a novel method to disperse fluorescent nanoparticles directly into the superfluid which become trapped on the vortex cores. Using a newly constructed multi-camera stereographic microscope, we present new data showing vortex reconnections and Kelvin waves with fully three-dimensional particle trajectories. These events are of scientific interest as they play a key role in the dissipation of quantum turbulence.

  12. A Three-Dimensional Cooperative Guidance Law of Multimissile System

    Directory of Open Access Journals (Sweden)

    Xing Wei

    2015-01-01

    Full Text Available In order to conduct saturation attacks on a static target, the cooperative guidance problem of multimissile system is researched. A three-dimensional guidance model is built using vector calculation and the classic proportional navigation guidance (PNG law is extended to three dimensions. Based on this guidance law, a distributed cooperative guidance strategy is proposed and a consensus protocol is designed to coordinate the time-to-go commands of all missiles. Then an expert system, which contains two extreme learning machines (ELM, is developed to regulate the local proportional coefficient of each missile according to the command. All missiles can arrive at the target simultaneously under the assumption that the multimissile network is connected. A simulation scenario is given to demonstrate the validity of the proposed method.

  13. Three-dimensional information encryption and anticounterfeiting using digital holography.

    Science.gov (United States)

    Shiu, Min-Tzung; Chew, Yang-Kun; Chan, Huang-Tian; Wong, Xin-Yu; Chang, Chi-Ching

    2015-01-01

    In this work, arbitrary micro phase-step digital holography with optical interferometry and digital image processing is utilized to obtain information about an image of a three-dimensional object and encrypting keys. Then, a computer-generated hologram is used for the purpose of holographic encryption. All information about the keys is required to perform the decryption, comprising the amplitude and phase distribution of the encrypting key, the distance of image reconstruction, zero-order term elimination, and twin-image term suppression. In addition to using identifiable information on different image planes and linear superposition processing hidden within the encrypted information, not only can we convey an important message, but we can also achieve anticounterfeiting. This approach retains the strictness of traditional holographic encryption and the convenience of digital holographic processing without image distortion. Therefore, this method provides better solutions to earlier methods for the security of the transmission of holographic information.

  14. Three-dimensional numerical simulation during laser processing of CFRP

    Science.gov (United States)

    Ohkubo, Tomomasa; Sato, Yuji; Matsunaga, Ei-ichi; Tsukamoto, Masahiro

    2017-09-01

    We performed three-dimensional numerical simulation about laser processing of carbon-fiber-reinforced plastic (CFRP) using OpenFOAM as libraries of finite volume method (FVM). Although a little theoretical or numerical studies about heat affected zone (HAZ) formation were performed, there is no research discussing how HAZ is generated considering time development about removal of each material. It is important to understand difference of removal speed of carbon fiber and resin in order to improve quality of cut surface of CFRP. We demonstrated how the carbon fiber and resin are removed by heat of ablation plume by our simulation. We found that carbon fiber is removed faster than resin at first stage because of the difference of thermal conductivity, and after that, the resin is removed faster because of its low combustion temperature. This result suggests the existence of optimal contacting time of the laser ablation and kerf of the target.

  15. Three-dimensional transparent parabolic concentrator for photovoltaics

    Directory of Open Access Journals (Sweden)

    Huichuan Lin

    2015-09-01

    Full Text Available A three-dimensional transparent parabolic concentrator made of polymethylmethacrylate (PMMA was designed and fabricated for photovoltaic applications. The measured maximum concentration ratio of the concentrator is 8.31, which means that for normal incident light, optical energy can be concentrated as high as 8.31 times by the concentrator. Even for oblique incident lights with an incident angle of between 5° and 15°, the concentrator maintains a concentration ratio of between 6.81 and 3.72. The concentrator was connected to Si cell, which increased the maximum output power of the Si cell by 12 times, compared with that of the bare cell. This indicates that the concentrator can increase the energy generated by Si cell by 12 times.

  16. Three-Dimensional Printing of Drug-Eluting Implants

    DEFF Research Database (Denmark)

    Water, Jorrit Jeroen; Bohr, Adam; Bøtker, Johan Peter

    2015-01-01

    The aim of the present work was to investigate the potential of three-dimensional (3D) printing as a manufacturing method for products intended for personalized treatments by exploring the production of novel polylactide-based feedstock materials for 3D printing purposes. Nitrofurantoin (NF......) and hydroxyapatite (HA) were successfully mixed and extruded with up to 30% drug load with and without addition of 5% HA in polylactide strands, which were subsequently 3D-printed into model disc geometries (10 × 2 mm). X-ray powder diffraction analysis showed that NF maintained its anhydrate solid form during...... of custom-made, drug-loaded feedstock materials for 3D printing of pharmaceutical products for controlled release....

  17. Applications of three-dimensional printing technology in urological practice.

    Science.gov (United States)

    Youssef, Ramy F; Spradling, Kyle; Yoon, Renai; Dolan, Benjamin; Chamberlin, Joshua; Okhunov, Zhamshid; Clayman, Ralph; Landman, Jaime

    2015-11-01

    A rapid expansion in the medical applications of three-dimensional (3D)-printing technology has been seen in recent years. This technology is capable of manufacturing low-cost and customisable surgical devices, 3D models for use in preoperative planning and surgical education, and fabricated biomaterials. While several studies have suggested 3D printers may be a useful and cost-effective tool in urological practice, few studies are available that clearly demonstrate the clinical benefit of 3D-printed materials. Nevertheless, 3D-printing technology continues to advance rapidly and promises to play an increasingly larger role in the field of urology. Herein, we review the current urological applications of 3D printing and discuss the potential impact of 3D-printing technology on the future of urological practice. © 2015 The Authors BJU International © 2015 BJU International Published by John Wiley & Sons Ltd.

  18. Three-dimensional flow measurements in a tesla turbine rotor

    Science.gov (United States)

    Fuchs, Thomas; Schosser, Constantin; Hain, Rainer; Kaehler, Christian

    2015-11-01

    Tesla turbines are fluid mechanical devices converting flow energy into rotation energy by two physical effects: friction and adhesion. The advantages of the tesla turbine are its simple and robust design, as well as its scalability, which makes it suitable for custom power supply solutions, and renewable energy applications. To this day, there is a lack of experimental data to validate theoretical studies, and CFD simulations of these turbines. This work presents a comprehensive analysis of the flow through a tesla turbine rotor gap, with a gap height of only 0.5 mm, by means of three-dimensional Particle Tracking Velocimetry (3D-PTV). For laminar flows, the experimental results match the theory very well, since the measured flow profiles show the predicted second order parabolic shape in radial direction and a fourth order behavior in circumferential direction. In addition to these laminar measurements, turbulent flows at higher mass flow rates were investigated.

  19. Three-dimensional periodic dielectric structures having photonic Dirac points

    Science.gov (United States)

    Bravo-Abad, Jorge; Joannopoulos, John D.; Soljacic, Marin

    2015-06-02

    The dielectric, three-dimensional photonic materials disclosed herein feature Dirac-like dispersion in quasi-two-dimensional systems. Embodiments include a face-centered cubic (fcc) structure formed by alternating layers of dielectric rods and dielectric slabs patterned with holes on respective triangular lattices. This fcc structure also includes a defect layer, which may comprise either dielectric rods or a dielectric slab with patterned with holes. This defect layer introduces Dirac cone dispersion into the fcc structure's photonic band structure. Examples of these fcc structures enable enhancement of the spontaneous emission coupling efficiency (the .beta.-factor) over large areas, contrary to the conventional wisdom that the .beta.-factor degrades as the system's size increases. These results enable large-area, low-threshold lasers; single-photon sources; quantum information processing devices; and energy harvesting systems.

  20. Validation of three-dimensional micro injection molding simulation accuracy

    DEFF Research Database (Denmark)

    Tosello, Guido; Costa, F.S.; Hansen, Hans Nørgaard

    2011-01-01

    the simulation accuracy (i.e. decrease deviations from experimental values): injection speed profile, cavity injection pressure, melt and mold temperatures, three-dimensional mesh parameters, and material rheological characterization. Quality factors investigated for the quantitative comparisons were: short shot...... length, injection pressure profile, molding mass and flow pattern. The importance of calibrated micro molding process monitoring for an accurate implementation strategy of the simulation and its validation has been demonstrated. In fact, inconsistencies and uncertainties in the experimental data must......Data analysis and simulations on micro-molding experiments have been conducted. Micro molding simulations have been executed taking into account actual processing conditions implementation in the software. Various aspects of the simulation set-up have been considered in order to improve...

  1. Phonon band structures of the three dimensional latticed pentamode metamaterials

    Directory of Open Access Journals (Sweden)

    Guan Wang

    2017-02-01

    Full Text Available The artificially designed three-dimensional (3D pentamode metamaterials have such an extraordinary characteristic that the solid materials behave like liquids. Meanwhile, the ideal structure of the pentamode metamaterials arranges in the same way as that of the diamond crystals. In the present research, we regard three types of pentamode metamaterials derived from the 3D crystal lattices as research objects. The phonon band structures of the candidate pentamode structures are calculated by using the finite element method (FEM. We illustrate the relation between the ratio of the bulk modulus B and the shear modulus G of different combinations of D and d. Finally, we find out the relationship between the phonon band structure and the structure parameters. It is useful for generating the phonon band structure and controlling elastic wave propagation.

  2. Spin wave steering in three-dimensional magnonic networks

    Science.gov (United States)

    Beginin, E. N.; Sadovnikov, A. V.; Sharaevskaya, A. Yu.; Stognij, A. I.; Nikitov, S. A.

    2018-03-01

    We report the concept of three-dimensional (3D) magnonic structures which are especially promising for controlling and manipulating magnon currents. The approach for fabrication of 3D magnonic crystals (MCs) and 3D magnonic networks is presented. A meander type ferromagnetic film grown at the top of the initially structured substrate can be a candidate for such 3D crystals. Using the finite element method, transfer matrix method, and micromagnetic simulations, we study spin-wave propagation in both isolated and coupled 3D MCs and reconstruct spin-wave dispersion and transmission response to elucidate the mechanism of magnonic bandgap formation. Our results show the possibility of the utilization of proposed structures for fabrication of a 3D magnonic network.

  3. Quantitative volumetric Raman imaging of three dimensional cell cultures

    KAUST Repository

    Kallepitis, Charalambos

    2017-03-22

    The ability to simultaneously image multiple biomolecules in biologically relevant three-dimensional (3D) cell culture environments would contribute greatly to the understanding of complex cellular mechanisms and cell–material interactions. Here, we present a computational framework for label-free quantitative volumetric Raman imaging (qVRI). We apply qVRI to a selection of biological systems: human pluripotent stem cells with their cardiac derivatives, monocytes and monocyte-derived macrophages in conventional cell culture systems and mesenchymal stem cells inside biomimetic hydrogels that supplied a 3D cell culture environment. We demonstrate visualization and quantification of fine details in cell shape, cytoplasm, nucleus, lipid bodies and cytoskeletal structures in 3D with unprecedented biomolecular specificity for vibrational microspectroscopy.

  4. An exactly solvable three-dimensional nonlinear quantum oscillator

    Energy Technology Data Exchange (ETDEWEB)

    Schulze-Halberg, A. [Department of Mathematics and Actuarial Science, Indiana University Northwest, 3400 Broadway, Gary, Indiana 46408 (United States); Morris, J. R. [Department of Physics, Indiana University Northwest, 3400 Broadway, Gary, Indiana 46408 (United States)

    2013-11-15

    Exact analytical, closed-form solutions, expressed in terms of special functions, are presented for the case of a three-dimensional nonlinear quantum oscillator with a position dependent mass. This system is the generalization of the corresponding one-dimensional system, which has been the focus of recent attention. In contrast to other approaches, we are able to obtain solutions in terms of special functions, without a reliance upon a Rodrigues-type of formula. The wave functions of the quantum oscillator have the familiar spherical harmonic solutions for the angular part. For the s-states of the system, the radial equation accepts solutions that have been recently found for the one-dimensional nonlinear quantum oscillator, given in terms of associated Legendre functions, along with a constant shift in the energy eigenvalues. Radial solutions are obtained for all angular momentum states, along with the complete energy spectrum of the bound states.

  5. Is a three-dimensional-printed tooth filling possible?

    Directory of Open Access Journals (Sweden)

    Muhammet Kerim Ayar

    2016-01-01

    Full Text Available Introduction: Three-dimensional (3-D printing is seen as an innovative production process in many fields of dentistry and medicine. But implantation of this novel production process into the treatment of decayed teeth in dentistry remains lacking. Destruction of dental tissues as a result of dental caries is generally treated with dental resin composite fillings. However, a 3-D-printed tooth filling approach, which could be an alternative to traditional approaches, has a potential to reduce treatment costs and technique-sensitivity of the placement of restorative material. The Hypothesis: Here, the hypothesis that a 3-D-printed tooth filling approach could be an alternative to traditional approaches to treatment of decayed teeth is proposed. Evaluation of the Hypothesis: The actual implementation of the 3-D-printed tooth filling technique in the practice of restorative dentistry was discussed in this manuscript.

  6. Brain lesion analysis using three-dimensional SPECT imaging

    International Nuclear Information System (INIS)

    Shibata, Iekado; Onagi, Atsuo; Kuroki, Takao

    1995-01-01

    A three-headed gamma camera (PRISM 3000) is capable to scan the protocol of early dynamic SPECT and to analyze two radioisotopes at the same time. We have framed three-dimensional brain SPECT images for several brain diseases by using the Application Visualization System (AVS). We carried out volume measurements in brain tumors and/or AVMs by applying this methodology. Thallium-201 and/or 123I-IMP were used for brain SPECT imaging. The dynamic scan protocol was changed in accordance with the given disease. The protocol for brain tumors was derived from a preliminary comparative study with thallium-201 and 123I-IMP that had suggested a disparity in the detection of brain tumors and the differentiation between tumor tissue and normal brain. The three-dimension SPECT image represented the brain tumor or AVM in a striking fashion, and the changes with respect to tumor or AVM after radiosurgery or embolization were understood readily. (author)

  7. Voro++: a three-dimensional Voronoi cell library in C++

    Energy Technology Data Exchange (ETDEWEB)

    Rycroft, Chris

    2009-01-15

    Voro++ is a free software library for the computation of three dimensional Voronoi cells. It is primarily designed for applications in physics and materials science, where the Voronoi tessellation can be a useful tool in the analysis of densely-packed particle systems, such as granular materials or glasses. The software comprises of several C++ classes that can be modified and incorporated into other programs. A command-line utility is also provided that can use most features of the code. Voro++ makes use of a direct cell-by-cell construction, which is particularly suited to handling special boundary conditions and walls. It employs algorithms which are tolerant for numerical precision errors, and it has been successfully employed on very large particle systems.

  8. The three-dimensional origin of the classifying algebra

    International Nuclear Information System (INIS)

    Fuchs, Juergen; Schweigert, Christoph; Stigner, Carl

    2010-01-01

    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 structure constants of the classifying algebra as invariants of ribbon graphs in the three-manifold S 2 xS 1 . Our result unravels a precise relation between intertwiners of the action of the mapping class group on spaces of conformal blocks and boundary conditions in rational conformal field theories.

  9. An exactly solvable three-dimensional nonlinear quantum oscillator

    International Nuclear Information System (INIS)

    Schulze-Halberg, A.; Morris, J. R.

    2013-01-01

    Exact analytical, closed-form solutions, expressed in terms of special functions, are presented for the case of a three-dimensional nonlinear quantum oscillator with a position dependent mass. This system is the generalization of the corresponding one-dimensional system, which has been the focus of recent attention. In contrast to other approaches, we are able to obtain solutions in terms of special functions, without a reliance upon a Rodrigues-type of formula. The wave functions of the quantum oscillator have the familiar spherical harmonic solutions for the angular part. For the s-states of the system, the radial equation accepts solutions that have been recently found for the one-dimensional nonlinear quantum oscillator, given in terms of associated Legendre functions, along with a constant shift in the energy eigenvalues. Radial solutions are obtained for all angular momentum states, along with the complete energy spectrum of the bound states

  10. Three-dimensional super Yang-Mills with unquenched flavor

    Science.gov (United States)

    Faedo, Antón F.; Mateos, David; Tarrío, Javier

    2015-07-01

    We construct analytically the gravity duals of three-dimensional, super Yang-Mills-type theories with supersymmetry coupled to N f quark flavors. The backreaction of the quarks on the color degrees of freedom is included, and corresponds on the gravity side to the backreaction of N f D6-branes on the background of N D2-branes. The D6-branes are smeared over the compact part of the geometry, which must be a six-dimensional nearly Kähler manifold in order to preserve supersymmetry. For massless quarks, the solutions flow in the IR to an AdS 4 fixed point dual to a Chern-Simons-matter theory. For light quarks the theories exhibit quasi-conformal dynamics (walking) at energy scales m q ≪ E ≪ λN f / N, with λ = g YM 2 N the 't Hooft coupling.

  11. Diffusion equation three-dimensional solution in rectangular subcritical assemblies

    International Nuclear Information System (INIS)

    Barroso, Dalton E.G.; Carvalho Vital, Helio de; Oliveira Vellozo, Sergio de; Paixao, Sergio Barros

    1997-01-01

    This work describes a three-dimensional diffusion code developed for neutron flux and current calculations in rectangular subcritical assemblies (loaded with fuel or not) with arbitrary point source distributions in their bases. The two-group analytical solution, expressed as Fourier's double series expansion, is calculated for each source. A summation is then performed over all sources to evaluate the total flux distributions. The input includes positions and activities of the external neutron sources, besides the effective two-group macroscopic cross sections. The code can also provide the individual contributions of the harmonics to the thermal and fast neutron flux and current. Calculation-to-Experiment comparisons for the thermal flux in a exponential pile have shown agreement within experimental errors. 11 refs., 3 figs., 3 tabs

  12. On the secondary instability of three-dimensional boundary layers

    Energy Technology Data Exchange (ETDEWEB)

    Janke, E. [DLR Deutsches Zentrum fuer Luft- und Raumfahrt e.V., Goettingen (Germany). Inst. fuer Stroemungsmechanik; Balakumar, P. [Department of Aerospace Engineering, Old Dominion University, Norfolk, VA 23529 (United States)

    2000-09-01

    One of the possible transition scenarios in three-dimensional boundary layers, the saturation of stationary crossflow vortices and their secondary instability to high-frequency disturbances, is studied using the parabolized stability equations (PSE) and Floquet theory. Starting from nonlinear PSE solutions, we investigate the region where a purely stationary crossflow disturbance saturates for its secondary instability characteristics utilizing global and local eigenvalue solvers that are based on the implicitly restarted Arnoldi method and a Newton-Raphson technique, respectively. Results are presented for swept Hiemenz flow and the DLR swept flat plate experiment. The main focuses of this study are on the existence of multiple roots in the eigenvalue spectrum that could explain experimental observations of time-dependent occurrences of an explosive growth of traveling disturbances, on the origin of high-frequency disturbances, as well as on gaining more information about threshold amplitudes of primary disturbances necessary for the growth of secondary disturbances. (orig.)

  13. Three-dimensional adult echocardiography: where the hidden dimension helps.

    Science.gov (United States)

    Mor-Avi, Victor; Sugeng, Lissa; Lang, Roberto M

    2008-05-01

    The introduction of three-dimensional (3D) imaging and its evolution from slow and labor-intense off-line reconstruction to real-time volumetric imaging is one of the most significant developments in ultrasound imaging of the heart of the past decade. This imaging modality currently provides valuable clinical information that empowers echocardiography with new levels of confidence in diagnosing heart disease. One major advantage of seeing the additional dimension is the improvement in the accuracy of the evaluation of cardiac chamber volumes by eliminating geometric modeling and the errors caused by foreshortened views. Another benefit of 3D imaging is the realistic views of cardiac valves capable of demonstrating numerous pathologies in a unique, noninvasive manner. This article reviews the major technological developments in 3D echocardiography and some of the recent literature that has provided the scientific basis for its clinical use.

  14. Three dimensional density cavities in guide field collisionless magnetic reconnection

    Science.gov (United States)

    Markidis, S.; Lapenta, G.; Divin, A.; Goldman, M.; Newman, D.; Andersson, L.

    2012-03-01

    Particle-in-cell simulations of collisionless magnetic reconnection with a guide field reveal for the first time the three dimensional features of the low density regions along the magnetic reconnection separatrices, the so-called cavities. It is found that structures with further lower density develop within the cavities. Because their appearance is similar to the rib shape, these formations are here called low density ribs. Their location remains approximately fixed in time and their density progressively decreases, as electron currents along the cavities evacuate them. They develop along the magnetic field lines and are supported by a strong perpendicular electric field that oscillates in space. In addition, bipolar parallel electric field structures form as isolated spheres between the cavities and the outflow plasma, along the direction of the low density ribs and of magnetic field lines.

  15. Three-dimensional imaging of atomic four-body processes

    CERN Document Server

    Schulz, M; Fischer, D; Kollmus, H; Madison, D H; Jones, S; Ullrich, J

    2003-01-01

    To understand the physical processes that occur in nature we need to obtain a solid concept about the 'fundamental' forces acting between pairs of elementary particles. it is also necessary to describe the temporal and spatial evolution of many mutually interacting particles under the influence of these forces. This latter step, known as the few-body problem, remains an important unsolved problem in physics. Experiments involving atomic collisions represent a useful testing ground for studying the few-body problem. For the single ionization of a helium atom by charged particle impact, kinematically complete experiments have been performed since 1969. The theoretical analysis of such experiments was thought to yield a complete picture of the basic features of the collision process, at least for large collision energies. These conclusions are, however, almost exclusively based on studies of restricted electron-emission geometries. We report three- dimensional images of the complete electron emission pattern for...

  16. Manufacturing of Three-dimensional Micro Structure Using Proton Beam

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Suonggyu; Kwon, Wontae [Seoul University, Seoul (Korea, Republic of)

    2015-04-15

    The diameter of a proton beam emanating from the MC-50 cyclotron is about 2?3 mm with Gaussian distribution. This widely irradiated proton beam is not suitable for semiconductor etching, precise positioning, and micromachining, which require a small spot. In this study, a beam cutting method using a microhole is proposed as an economical alternative. We produced a microhole with aspect ratio, average diameter, and thickness of 428, 21 μm, and 9 mm, respectively, for cutting the proton beam. By using this high-aspect-ratio microhole, we conducted machinability tests on microstructures with sizes of tens of μm. Additionally, the results of simulation using GEANT4 and those of the actual experiment were compared and analyzed. The outcome confirmed the possibility of implementing a micro process technology for the fabrication of three-dimensional microstructures of 20 micron units using the MC-50 cyclotron with the microhole.

  17. Black holes in three dimensional higher spin gravity: a review

    Science.gov (United States)

    Ammon, Martin; Gutperle, Michael; Kraus, Per; Perlmutter, Eric

    2013-05-01

    We review recent progress in the construction of black holes in three dimensional higher spin gravity theories. Starting from spin-3 gravity and working our way toward the theory of an infinite tower of higher spins coupled to matter, we show how to harness higher spin gauge invariance to consistently generalize familiar notions of black holes. We review the construction of black holes with conserved higher spin charges and the computation of their partition functions to leading asymptotic order. In view of the anti-de Sitter/conformal field theory (CFT) correspondence as applied to certain vector-like conformal field theories with extended conformal symmetry, we successfully compare to CFT calculations in a generalized Cardy regime. A brief recollection of pertinent aspects of ordinary gravity is also given. This article is part of a special issue of Journal of Physics A: Mathematical and Theoretical devoted to ‘Higher spin theories and holography’.

  18. Shape synchronization control for three-dimensional chaotic systems

    International Nuclear Information System (INIS)

    Huang, Yuanyuan; Wang, Yinhe; Chen, Haoguang; Zhang, Siying

    2016-01-01

    This paper aims to the three-dimensional continuous chaotic system and shape of the chaotic attractor by utilizing the basic theory of plane curves in classical differential geometry, the continuous controller is synthesized for the master–slave synchronization in shape. This means that the slave system can possess the same shape of state trajectory with the master system via the continuous controller. The continuous controller is composed of three sub-controllers, which respectively correspond to the master–slave synchronization in shape for the three projective curves of the chaotic attractor onto the three coordinate planes. Moreover, the proposed shape synchronization technique as well as application of control scheme to secure communication is also demonstrated in this paper, where numerical simulation results show the proposed control method works well.

  19. Micro-fabrication of three dimensional pyrolysed carbon microelectrodes

    DEFF Research Database (Denmark)

    2017-01-01

    ; soft baking the photoresist layer; performing a full depth exposure with UV light through a first mask; performing a partial depth exposure with UV light through a second mask; wherein the full depth exposure and the partial depth exposure are aligned to ensure that the first and second latent images...... are connected to each other; post-exposure baking the photoresist layer; and developing the microscale patterned resist template as a free-standing structure of cross-linked resist with lateral hanging structures that are supported by vertical support structures at a free height above the substrate. The method...... is characterized by a soft baking temperature below 70 °C. Repetitive coating and partial depth exposure allows for the fabrication of multiple level laterally interconnected structures. Carbonization of the resist template provides truly three-dimensional carbon microelectrode structures....

  20. Three-dimensional protein structure prediction: Methods and computational strategies.

    Science.gov (United States)

    Dorn, Márcio; E Silva, Mariel Barbachan; Buriol, Luciana S; Lamb, Luis C

    2014-10-12

    A long standing problem in structural bioinformatics is to determine the three-dimensional (3-D) structure of a protein when only a sequence of amino acid residues is given. Many computational methodologies and algorithms have been proposed as a solution to the 3-D Protein Structure Prediction (3-D-PSP) problem. These methods can be divided in four main classes: (a) first principle methods without database information; (b) first principle methods with database information; (c) fold recognition and threading methods; and (d) comparative modeling methods and sequence alignment strategies. Deterministic computational techniques, optimization techniques, data mining and machine learning approaches are typically used in the construction of computational solutions for the PSP problem. Our main goal with this work is to review the methods and computational strategies that are currently used in 3-D protein prediction. Copyright © 2014 Elsevier Ltd. All rights reserved.