Three-dimensional-printed cardiac prototypes aid surgical decision-making and preoperative planning in selected cases of complex congenital heart diseases: Early experience and proof of concept in a resource-limited environment.

PubMed

Kappanayil, Mahesh; Koneti, Nageshwara Rao; Kannan, Rajesh R; Kottayil, Brijesh P; Kumar, Krishna

2017-01-01

Three-dimensional. (3D) printing is an innovative manufacturing process that allows computer-assisted conversion of 3D imaging data into physical "printouts" Healthcare applications are currently in evolution. The objective of this study was to explore the feasibility and impact of using patient-specific 3D-printed cardiac prototypes derived from high-resolution medical imaging data (cardiac magnetic resonance imaging/computed tomography [MRI/CT]) on surgical decision-making and preoperative planning in selected cases of complex congenital heart diseases (CHDs). Five patients with complex CHD with previously unresolved management decisions were chosen. These included two patients with complex double-outlet right ventricle, two patients with criss-cross atrioventricular connections, and one patient with congenitally corrected transposition of great arteries with pulmonary atresia. Cardiac MRI was done for all patients, cardiac CT for one; specific surgical challenges were identified. Volumetric data were used to generate patient-specific 3D models. All cases were reviewed along with their 3D models, and the impact on surgical decision-making and preoperative planning was assessed. Accurate life-sized 3D cardiac prototypes were successfully created for all patients. The models enabled radically improved 3D understanding of anatomy, identification of specific technical challenges, and precise surgical planning. Augmentation of existing clinical and imaging data by 3D prototypes allowed successful execution of complex surgeries for all five patients, in accordance with the preoperative planning. 3D-printed cardiac prototypes can radically assist decision-making, planning, and safe execution of complex congenital heart surgery by improving understanding of 3D anatomy and allowing anticipation of technical challenges.

Heterobimetallic thiocyanato-bridged coordination polymers based on [Hg(SCN){sub 4}]{sup 2-}: Synthesis, crystal structure, magnetic properties and ESR studies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jian Fangfang; Xiao Hailian; Liu Faqian

2006-12-15

Three new M/Hg bimetallic thiocyanato-bridged coordination polymers; [Hg(SCN){sub 4}Ni(Im){sub 3}] {sub {infinity}} 1, [Hg(SCN){sub 4}Mn(Im){sub 2}] {sub {infinity}} 2, and [Hg(SCN){sub 4}Cu(Me-Im){sub 2} Hg(SCN){sub 4}Cu(Me-Im){sub 4}] {sub {infinity}} 3, (Im=imidazole, Me-Im=N-methyl-imidazole), have been synthesized and characterized by means of elemental analysis, ESR, and single-crystal X-ray. X-ray diffraction analysis reveals that these three complexes all form 3D network structure, and their structures all contain a thiocyanato-bridged Hg...Hg chain (M=Mn, Ni, Cu) in which the metal and mercury centers exhibit different coordination environments. In complex 1, the [Hg(SCN){sub 4}]{sup 2-} anion connects three [Ni(Im){sub 3}]{sup 2+} using three SCN ligands giving risemore » to a 3D structure, and in complex 2, four SCN ligands bridge [Hg(SCN){sub 4}]{sup 2-} and [Mn(Im){sub 2}]{sup 2+} to form a 3D structure. The structure of 3 contains two copper atoms with distinct coordination environment; one is coordinated by four N-methyl-imidazole ligands and two axially elongated SCN groups, and another by four SCN groups (two elongated) and two N-methyl-imidazole ligands. The magnetic property of complex 1 has been investigated. The spin state structure in hetermetallic NiHgNi systems of complex 1 is irregular. The ESR spectra results of complex 3 demonstrate Cu{sup 2+} ion lie on octahedral environment. -- Graphical abstract: Three new M/Hg bimetallic thiocyanato-bridged coordination polymers; [Hg(SCN){sub 4}Ni(Im){sub 3}] {sub {infinity}} 1, [Hg(SCN){sub 4}Mn(Im){sub 2}] {sub {infinity}} 2, and [Hg(SCN){sub 4}Cu(Me-Im){sub 2} Hg(SCN){sub 4}Cu(Me-Im){sub 4}] {sub {infinity}} 3, (Im=imidazole, Me-Im=N-methyl-imidazole), have been synthesized and characterized by single-crystal X-ray. All coordination polymers possess 3-D structures, and consist of organic base neutral ligands (imidazole and N-methyl-imidazole) and SCN{sup -1} anions. Their structural difference is maicaused by the role of the organic base and metal ions. The complex 1 shows the irregular spin state structure.« less

Openwebglobe 2: Visualization of Complex 3D-GEODATA in the (mobile) Webbrowser

NASA Astrophysics Data System (ADS)

Christen, M.

2016-06-01

Providing worldwide high resolution data for virtual globes consists of compute and storage intense tasks for processing data. Furthermore, rendering complex 3D-Geodata, such as 3D-City models with an extremely high polygon count and a vast amount of textures at interactive framerates is still a very challenging task, especially on mobile devices. This paper presents an approach for processing, caching and serving massive geospatial data in a cloud-based environment for large scale, out-of-core, highly scalable 3D scene rendering on a web based virtual globe. Cloud computing is used for processing large amounts of geospatial data and also for providing 2D and 3D map data to a large amount of (mobile) web clients. In this paper the approach for processing, rendering and caching very large datasets in the currently developed virtual globe "OpenWebGlobe 2" is shown, which displays 3D-Geodata on nearly every device.

How Does a Modern Field Artillery Cannon Battalion Operate in a Degraded, Denied, and Disrupted Space Operating Environment

DTIC Science & Technology

2017-06-09

reports, a potential solution to communication shortfalls was the use of high frequency (HF) Harris radios that possess complex encryption... communications , positioning, and navigation do not properly function, is known as a Degraded, Denied, Disrupted Space Operating Environment (D3SOE).7...battalion operates in a D3SOE. This was a very relevant question for a force increasingly reliant on frequency modulated (FM) radio communication systems

Surgical approaches to complex vascular lesions: the use of virtual reality and stereoscopic analysis as a tool for resident and student education.

PubMed

Agarwal, Nitin; Schmitt, Paul J; Sukul, Vishad; Prestigiacomo, Charles J

2012-08-01

Virtual reality training for complex tasks has been shown to be of benefit in fields involving highly technical and demanding skill sets. The use of a stereoscopic three-dimensional (3D) virtual reality environment to teach a patient-specific analysis of the microsurgical treatment modalities of a complex basilar aneurysm is presented. Three different surgical approaches were evaluated in a virtual environment and then compared to elucidate the best surgical approach. These approaches were assessed with regard to the line-of-sight, skull base anatomy and visualisation of the relevant anatomy at the level of the basilar artery and surrounding structures. Overall, the stereoscopic 3D virtual reality environment with fusion of multimodality imaging affords an excellent teaching tool for residents and medical students to learn surgical approaches to vascular lesions. Future studies will assess the educational benefits of this modality and develop a series of metrics for student assessments.

Imaging of human differentiated 3D neural aggregates using light sheet fluorescence microscopy.

PubMed

Gualda, Emilio J; Simão, Daniel; Pinto, Catarina; Alves, Paula M; Brito, Catarina

2014-01-01

The development of three dimensional (3D) cell cultures represents a big step for the better understanding of cell behavior and disease in a more natural like environment, providing not only single but multiple cell type interactions in a complex 3D matrix, highly resembling physiological conditions. Light sheet fluorescence microscopy (LSFM) is becoming an excellent tool for fast imaging of such 3D biological structures. We demonstrate the potential of this technique for the imaging of human differentiated 3D neural aggregates in fixed and live samples, namely calcium imaging and cell death processes, showing the power of imaging modality compared with traditional microscopy. The combination of light sheet microscopy and 3D neural cultures will open the door to more challenging experiments involving drug testing at large scale as well as a better understanding of relevant biological processes in a more realistic environment.

Imaging of human differentiated 3D neural aggregates using light sheet fluorescence microscopy

PubMed Central

Gualda, Emilio J.; Simão, Daniel; Pinto, Catarina; Alves, Paula M.; Brito, Catarina

2014-01-01

The development of three dimensional (3D) cell cultures represents a big step for the better understanding of cell behavior and disease in a more natural like environment, providing not only single but multiple cell type interactions in a complex 3D matrix, highly resembling physiological conditions. Light sheet fluorescence microscopy (LSFM) is becoming an excellent tool for fast imaging of such 3D biological structures. We demonstrate the potential of this technique for the imaging of human differentiated 3D neural aggregates in fixed and live samples, namely calcium imaging and cell death processes, showing the power of imaging modality compared with traditional microscopy. The combination of light sheet microscopy and 3D neural cultures will open the door to more challenging experiments involving drug testing at large scale as well as a better understanding of relevant biological processes in a more realistic environment. PMID:25161607

Fast, Automated, Scalable Generation of Textured 3D Models of Indoor Environments

DTIC Science & Technology

2014-12-18

expensive travel and on-site visits. Different applications require models of different complexities, both with and without furniture geometry. The...environment and to localize the system in the environment over time. The datasets shown in this paper were generated by a backpack -mounted system that uses 2D...voxel is found to intersect the line segment from a scanner to a corresponding scan point. If a laser passes through a voxel, that voxel is considered

iCAVE: an open source tool for visualizing biomolecular networks in 3D, stereoscopic 3D and immersive 3D

PubMed Central

Liluashvili, Vaja; Kalayci, Selim; Fluder, Eugene; Wilson, Manda; Gabow, Aaron

2017-01-01

Abstract Visualizations of biomolecular networks assist in systems-level data exploration in many cellular processes. Data generated from high-throughput experiments increasingly inform these networks, yet current tools do not adequately scale with concomitant increase in their size and complexity. We present an open source software platform, interactome-CAVE (iCAVE), for visualizing large and complex biomolecular interaction networks in 3D. Users can explore networks (i) in 3D using a desktop, (ii) in stereoscopic 3D using 3D-vision glasses and a desktop, or (iii) in immersive 3D within a CAVE environment. iCAVE introduces 3D extensions of known 2D network layout, clustering, and edge-bundling algorithms, as well as new 3D network layout algorithms. Furthermore, users can simultaneously query several built-in databases within iCAVE for network generation or visualize their own networks (e.g., disease, drug, protein, metabolite). iCAVE has modular structure that allows rapid development by addition of algorithms, datasets, or features without affecting other parts of the code. Overall, iCAVE is the first freely available open source tool that enables 3D (optionally stereoscopic or immersive) visualizations of complex, dense, or multi-layered biomolecular networks. While primarily designed for researchers utilizing biomolecular networks, iCAVE can assist researchers in any field. PMID:28814063

iCAVE: an open source tool for visualizing biomolecular networks in 3D, stereoscopic 3D and immersive 3D.

PubMed

Liluashvili, Vaja; Kalayci, Selim; Fluder, Eugene; Wilson, Manda; Gabow, Aaron; Gümüs, Zeynep H

2017-08-01

Visualizations of biomolecular networks assist in systems-level data exploration in many cellular processes. Data generated from high-throughput experiments increasingly inform these networks, yet current tools do not adequately scale with concomitant increase in their size and complexity. We present an open source software platform, interactome-CAVE (iCAVE), for visualizing large and complex biomolecular interaction networks in 3D. Users can explore networks (i) in 3D using a desktop, (ii) in stereoscopic 3D using 3D-vision glasses and a desktop, or (iii) in immersive 3D within a CAVE environment. iCAVE introduces 3D extensions of known 2D network layout, clustering, and edge-bundling algorithms, as well as new 3D network layout algorithms. Furthermore, users can simultaneously query several built-in databases within iCAVE for network generation or visualize their own networks (e.g., disease, drug, protein, metabolite). iCAVE has modular structure that allows rapid development by addition of algorithms, datasets, or features without affecting other parts of the code. Overall, iCAVE is the first freely available open source tool that enables 3D (optionally stereoscopic or immersive) visualizations of complex, dense, or multi-layered biomolecular networks. While primarily designed for researchers utilizing biomolecular networks, iCAVE can assist researchers in any field. © The Authors 2017. Published by Oxford University Press.

Panthere V2: Multipurpose Simulation Software for 3D Dose Rate Calculations

NASA Astrophysics Data System (ADS)

Penessot, Gaël; Bavoil, Éléonore; Wertz, Laurent; Malouch, Fadhel; Visonneau, Thierry; Dubost, Julien

2017-09-01

PANTHERE is a multipurpose radiation protection software developed by EDF to calculate gamma dose rates in complex 3D environments. PANTHERE takes a key role in the EDF ALARA process, enabling to predict dose rates and to organize and optimize operations in high radiation environments. PANTHERE is also used for nuclear waste characterization, transport of nuclear materials, etc. It is used in most of the EDF engineering units and their design service providers and industrial partners.

3D-printed microfluidic chips with patterned, cell-laden hydrogel constructs.

PubMed

Knowlton, Stephanie; Yu, Chu Hsiang; Ersoy, Fulya; Emadi, Sharareh; Khademhosseini, Ali; Tasoglu, Savas

2016-06-20

Three-dimensional (3D) printing offers potential to fabricate high-throughput and low-cost fabrication of microfluidic devices as a promising alternative to traditional techniques which enables efficient design iterations in the development stage. In this study, we demonstrate a single-step fabrication of a 3D transparent microfluidic chip using two alternative techniques: a stereolithography-based desktop 3D printer and a two-step fabrication using an industrial 3D printer based on polyjet technology. This method, compared to conventional fabrication using relatively expensive materials and labor-intensive processes, presents a low-cost, rapid prototyping technique to print functional 3D microfluidic chips. We enhance the capabilities of 3D-printed microfluidic devices by coupling 3D cell encapsulation and spatial patterning within photocrosslinkable gelatin methacryloyl (GelMA). The platform presented here serves as a 3D culture environment for long-term cell culture and growth. Furthermore, we have demonstrated the ability to print complex 3D microfluidic channels to create predictable and controllable fluid flow regimes. Here, we demonstrate the novel use of 3D-printed microfluidic chips as controllable 3D cell culture environments, advancing the applicability of 3D printing to engineering physiological systems for future applications in bioengineering.

Multi-Level Adaptation in End-User Development of 3D Virtual Chemistry Experiments

ERIC Educational Resources Information Center

Liu, Chang; Zhong, Ying

2014-01-01

Multi-level adaptation in end-user development (EUD) is an effective way to enable non-technical end users such as educators to gradually introduce more functionality with increasing complexity to 3D virtual learning environments developed by themselves using EUD approaches. Parameterization, integration, and extension are three levels of…

Interior Reconstruction Using the 3d Hough Transform

NASA Astrophysics Data System (ADS)

Dumitru, R.-C.; Borrmann, D.; Nüchter, A.

2013-02-01

Laser scanners are often used to create accurate 3D models of buildings for civil engineering purposes, but the process of manually vectorizing a 3D point cloud is time consuming and error-prone (Adan and Huber, 2011). Therefore, the need to characterize and quantify complex environments in an automatic fashion arises, posing challenges for data analysis. This paper presents a system for 3D modeling by detecting planes in 3D point clouds, based on which the scene is reconstructed at a high architectural level through removing automatically clutter and foreground data. The implemented software detects openings, such as windows and doors and completes the 3D model by inpainting.

Syntheses, structures and photoelectric properties of a series of Cd(II)/Zn(II) coordination polymers and coordination supramolecules

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jin Jing; Han Xiao; Meng Qin

2013-01-15

Five Cd(II)/Zn(II) complexes [Cd(1,2-bdc)(pz){sub 2}(H{sub 2}O)]{sub n} (1), [Cd1Cd2(btec)(H{sub 2}O){sub 6}]{sub n} (2), [Cd(3,4-pdc) (H{sub 2}O)]{sub n} (3), [Zn(2,5-pdc)(H{sub 2}O){sub 4}]{center_dot}2H{sub 2}O (4) and {l_brace} [Zn(2,5-pdc)(H{sub 2}O){sub 2}]{center_dot}H{sub 2}O{r_brace} {sub n} (5) (H{sub 2}bdc=1,2-benzenedicarboxylic acid, pz=pyrazole, H{sub 4}btec=1,2,4,5-benzenetetracarboxylic acid, H{sub 2}pdc=pyridine-dicarboxylic acid) were hydrothermally synthesized and characterized by single-crystal X-ray diffraction, surface photovoltage spectroscopy, XRD, TG analysis, IR and UV-vis spectra and elemental analysis. Structural analyses show that complexes 1-3 are 1D, 2D and 3D Cd(II) coordination polymers, respectively. Complex 4 is a mononuclear Zn(II) complex. Complex 5 is a 3D Zn(II) coordination polymer. The surface photoelectric properties of complexesmore » were investigated by SPS. The results indicate that all complexes exhibit photoelectric responses in the range of 300-600 nm, which reveals that they all possess certain photoelectric conversion properties. By the comparative analyses, it can be found that the species and coordination micro-environment of central metal ion, the species and property of ligands affect the intensity and scope of photoelectric response. - Graphical abstract: Five Cd(II)/Zn(II) complexes have been hydrothermally synthesized and characterized. The photoelectric properties were studied with SPS. The species and coordination micro-environment of central metal ion, the species and property of ligands all affect the photoelectric responses. Highlights: Black-Right-Pointing-Pointer Five Cd/Zn complexes have been synthesized and characterized. Black-Right-Pointing-Pointer The SPS results indicate they possess obvious photoelectric conversion property. Black-Right-Pointing-Pointer The species and coordination environment of central metal ion affect SPS. Black-Right-Pointing-Pointer The species and property of ligands affect SPS. Black-Right-Pointing-Pointer By the energy-band theory and the crystal filed theory, the SPS are analyzed and assigned.« less

Diamond and diamond-like carbon MEMS

NASA Astrophysics Data System (ADS)

Luo, J. K.; Fu, Y. Q.; Le, H. R.; Williams, J. A.; Spearing, S. M.; Milne, W. I.

2007-07-01

To generate complex cartilage/bone tissues, scaffolds must possess several structural features that are difficult to create using conventional scaffold design/fabrication technologies. Successful cartilage/bone regeneration depends on the ability to assemble chondrocytes/osteoblasts into three-dimensional (3D) scaffolds. Therefore, we developed a 3D scaffold fabrication system that applies the axiomatic approach to our microstereolithography system. The new system offers a reduced machine size by minimizing the optical components, and shows that the design matrix is decoupled. This analysis identified the key factors affecting microstructure fabrication and an improved scaffold fabrication system was constructed. The results demonstrate that precise, predesigned 3D structures can be fabricated. Using this 3D scaffold, cell adhesion behavior was observed. The use of 3D scaffolds might help determine key factors in the study of cell behavior in complex environments and could eventually lead to the optimal design of scaffolds for the regeneration of various tissues, such as cartilage and bone.

A Head in Virtual Reality: Development of A Dynamic Head and Neck Model

ERIC Educational Resources Information Center

Nguyen, Ngan; Wilson, Timothy D.

2009-01-01

Advances in computer and interface technologies have made it possible to create three-dimensional (3D) computerized models of anatomical structures for visualization, manipulation, and interaction in a virtual 3D environment. In the past few decades, a multitude of digital models have been developed to facilitate complex spatial learning of the…

Quantitative volumetric Raman imaging of three dimensional cell cultures

NASA Astrophysics Data System (ADS)

Kallepitis, Charalambos; Bergholt, Mads S.; Mazo, Manuel M.; Leonardo, Vincent; Skaalure, Stacey C.; Maynard, Stephanie A.; Stevens, Molly M.

2017-03-01

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.

Sockeye: A 3D Environment for Comparative Genomics

PubMed Central

Montgomery, Stephen B.; Astakhova, Tamara; Bilenky, Mikhail; Birney, Ewan; Fu, Tony; Hassel, Maik; Melsopp, Craig; Rak, Marcin; Robertson, A. Gordon; Sleumer, Monica; Siddiqui, Asim S.; Jones, Steven J.M.

2004-01-01

Comparative genomics techniques are used in bioinformatics analyses to identify the structural and functional properties of DNA sequences. As the amount of available sequence data steadily increases, the ability to perform large-scale comparative analyses has become increasingly relevant. In addition, the growing complexity of genomic feature annotation means that new approaches to genomic visualization need to be explored. We have developed a Java-based application called Sockeye that uses three-dimensional (3D) graphics technology to facilitate the visualization of annotation and conservation across multiple sequences. This software uses the Ensembl database project to import sequence and annotation information from several eukaryotic species. A user can additionally import their own custom sequence and annotation data. Individual annotation objects are displayed in Sockeye by using custom 3D models. Ensembl-derived and imported sequences can be analyzed by using a suite of multiple and pair-wise alignment algorithms. The results of these comparative analyses are also displayed in the 3D environment of Sockeye. By using the Java3D API to visualize genomic data in a 3D environment, we are able to compactly display cross-sequence comparisons. This provides the user with a novel platform for visualizing and comparing genomic feature organization. PMID:15123592

Hafnium(IV) chloride complexes with chelating β-ketiminate ligands: Synthesis, spectroscopic characterization and volatility study

NASA Astrophysics Data System (ADS)

Patil, Siddappa A.; Medina, Phillip A.; Antic, Aleks; Ziller, Joseph W.; Vohs, Jason K.; Fahlman, Bradley D.

2015-09-01

The synthesis and characterization of four new β-ketiminate hafnium(IV) chloride complexes dichloro-bis[4-(phenylamido)pent-3-en-2-one]-hafnium (4a), dichloro-bis[4-(4-methylphenylamido)pent-3-en-2-one]-hafnium (4b), dichloro-bis[4-(4-methoxyphenylamido)pent-3-en-2-one]-hafnium (4c), and dichloro-bis[4-(4-chlorophenylamido)pent-3-en-2-one]-hafnium (4d) are reported. All the complexes (4a-d) were characterized by spectroscopic methods (1H NMR, 13C NMR, IR), and elemental analysis while the compound 4c was further examined by single-crystal X-ray diffraction, revealing that the complex is monomer with the hafnium center in octahedral coordination environment and oxygens of the chelating N-O ligands are trans to each other and the chloride ligands are in a cis arrangement. Volatile trends are established for four new β-ketiminate hafnium(IV) chloride complexes (4a-d). Sublimation enthalpies (ΔHsub) were calculated from thermogravimetric analysis (TGA) data, which show that, the dependence of ΔHsub on the molecular weight (4a-c) and inductive effects from chlorine (4d).

Immersive 3D geovisualisation in higher education

NASA Astrophysics Data System (ADS)

Philips, Andrea; Walz, Ariane; Bergner, Andreas; Graeff, Thomas; Heistermann, Maik; Kienzler, Sarah; Korup, Oliver; Lipp, Torsten; Schwanghart, Wolfgang; Zeilinger, Gerold

2014-05-01

Through geovisualisation we explore spatial data, we analyse it towards a specific questions, we synthesise results, and we present and communicate them to a specific audience (MacEachren & Kraak 1997). After centuries of paper maps, the means to represent and visualise our physical environment and its abstract qualities have changed dramatically since the 1990s - and accordingly the methods how to use geovisualisation in teaching. Whereas some people might still consider the traditional classroom as ideal setting for teaching and learning geographic relationships and its mapping, we used a 3D CAVE (computer-animated virtual environment) as environment for a problem-oriented learning project called "GEOSimulator". Focussing on this project, we empirically investigated, if such a technological advance like the CAVE make 3D visualisation, including 3D geovisualisation, not only an important tool for businesses (Abulrub et al. 2012) and for the public (Wissen et al. 2008), but also for educational purposes, for which it had hardly been used yet. The 3D CAVE is a three-sided visualisation platform, that allows for immersive and stereoscopic visualisation of observed and simulated spatial data. We examined the benefits of immersive 3D visualisation for geographic research and education and synthesized three fundamental technology-based visual aspects: First, the conception and comprehension of space and location does not need to be generated, but is instantaneously and intuitively present through stereoscopy. Second, optical immersion into virtual reality strengthens this spatial perception which is in particular important for complex 3D geometries. And third, a significant benefit is interactivity, which is enhanced through immersion and allows for multi-discursive and dynamic data exploration and knowledge transfer. Based on our problem-oriented learning project, which concentrates on a case study on flood risk management at the Wilde Weisseritz in Germany, a river that significantly contributed to the hundred-year flooding in Dresden in 2002, we empirically evaluated the usefulness of this immersive 3D technology towards learning success. Results show that immersive 3D geovisualisation have educational and content-related advantages compared to 2D geovisualisations through the mentioned benefits. This innovative way of geovisualisation is thus not only entertaining and motivating for students, but can also be constructive for research studies by, for instance, facilitating the study of complex environments or decision-making processes.

Ames Lab 101: osgBullet

ScienceCinema

McCorkle, Doug

2017-12-27

Ames Laboratory scientist Doug McCorkle explains osgBullet, a 3-D virtual simulation software, and how it helps engineers design complex products and systems in a realistic, real-time virtual environment.

The cranial nerve skywalk: A 3D tutorial of cranial nerves in a virtual platform.

PubMed

Richardson-Hatcher, April; Hazzard, Matthew; Ramirez-Yanez, German

2014-01-01

Visualization of the complex courses of the cranial nerves by students in the health-related professions is challenging through either diagrams in books or plastic models in the gross laboratory. Furthermore, dissection of the cranial nerves in the gross laboratory is an extremely meticulous task. Teaching and learning the cranial nerve pathways is difficult using two-dimensional (2D) illustrations alone. Three-dimensional (3D) models aid the teacher in describing intricate and complex anatomical structures and help students visualize them. The study of the cranial nerves can be supplemented with 3D, which permits the students to fully visualize their distribution within the craniofacial complex. This article describes the construction and usage of a virtual anatomy platform in Second Life™, which contains 3D models of the cranial nerves III, V, VII, and IX. The Cranial Nerve Skywalk features select cranial nerves and the associated autonomic pathways in an immersive online environment. This teaching supplement was introduced to groups of pre-healthcare professional students in gross anatomy courses at both institutions and student feedback is included. © 2014 American Association of Anatomists.

Analysis and Processing the 3D-Range-Image-Data for Robot Monitoring

NASA Astrophysics Data System (ADS)

Kohoutek, Tobias

2008-09-01

Industrial robots are commonly used for physically stressful jobs in complex environments. In any case collisions with heavy and high dynamic machines need to be prevented. For this reason the operational range has to be monitored precisely, reliably and meticulously. The advantage of the SwissRanger® SR-3000 is that it delivers intensity images and 3D-information simultaneously of the same scene that conveniently allows 3D-monitoring. Due to that fact automatic real time collision prevention within the robots working space is possible by working with 3D-coordinates.

LONI visualization environment.

PubMed

Dinov, Ivo D; Valentino, Daniel; Shin, Bae Cheol; Konstantinidis, Fotios; Hu, Guogang; MacKenzie-Graham, Allan; Lee, Erh-Fang; Shattuck, David; Ma, Jeff; Schwartz, Craig; Toga, Arthur W

2006-06-01

Over the past decade, the use of informatics to solve complex neuroscientific problems has increased dramatically. Many of these research endeavors involve examining large amounts of imaging, behavioral, genetic, neurobiological, and neuropsychiatric data. Superimposing, processing, visualizing, or interpreting such a complex cohort of datasets frequently becomes a challenge. We developed a new software environment that allows investigators to integrate multimodal imaging data, hierarchical brain ontology systems, on-line genetic and phylogenic databases, and 3D virtual data reconstruction models. The Laboratory of Neuro Imaging visualization environment (LONI Viz) consists of the following components: a sectional viewer for imaging data, an interactive 3D display for surface and volume rendering of imaging data, a brain ontology viewer, and an external database query system. The synchronization of all components according to stereotaxic coordinates, region name, hierarchical ontology, and genetic labels is achieved via a comprehensive BrainMapper functionality, which directly maps between position, structure name, database, and functional connectivity information. This environment is freely available, portable, and extensible, and may prove very useful for neurobiologists, neurogenetisists, brain mappers, and for other clinical, pedagogical, and research endeavors.

An interactive, stereoscopic virtual environment for medical imaging visualization, simulation and training

NASA Astrophysics Data System (ADS)

Krueger, Evan; Messier, Erik; Linte, Cristian A.; Diaz, Gabriel

2017-03-01

Recent advances in medical image acquisition allow for the reconstruction of anatomies with 3D, 4D, and 5D renderings. Nevertheless, standard anatomical and medical data visualization still relies heavily on the use of traditional 2D didactic tools (i.e., textbooks and slides), which restrict the presentation of image data to a 2D slice format. While these approaches have their merits beyond being cost effective and easy to disseminate, anatomy is inherently three-dimensional. By using 2D visualizations to illustrate more complex morphologies, important interactions between structures can be missed. In practice, such as in the planning and execution of surgical interventions, professionals require intricate knowledge of anatomical complexities, which can be more clearly communicated and understood through intuitive interaction with 3D volumetric datasets, such as those extracted from high-resolution CT or MRI scans. Open source, high quality, 3D medical imaging datasets are freely available, and with the emerging popularity of 3D display technologies, affordable and consistent 3D anatomical visualizations can be created. In this study we describe the design, implementation, and evaluation of one such interactive, stereoscopic visualization paradigm for human anatomy extracted from 3D medical images. A stereoscopic display was created by projecting the scene onto the lab floor using sequential frame stereo projection and viewed through active shutter glasses. By incorporating a PhaseSpace motion tracking system, a single viewer can navigate an augmented reality environment and directly manipulate virtual objects in 3D. While this paradigm is sufficiently versatile to enable a wide variety of applications in need of 3D visualization, we designed our study to work as an interactive game, which allows users to explore the anatomy of various organs and systems. In this study we describe the design, implementation, and evaluation of an interactive and stereoscopic visualization platform for exploring and understanding human anatomy. This system can present medical imaging data in three dimensions and allows for direct physical interaction and manipulation by the viewer. This should provide numerous benefits over traditional, 2D display and interaction modalities, and in our analysis, we aim to quantify and qualify users' visual and motor interactions with the virtual environment when employing this interactive display as a 3D didactic tool.

3D Reconstruction of Frozen Plant Tissue: a unique histological analysis to image post-freeze responses

USDA-ARS?s Scientific Manuscript database

Winter hardiness in plants is the result of a complex interaction between genes, the tissue where those genes are expressed and the environment. The light microscope is a valuable tool to understand this complexity which will ultimately help researchers improve the tolerance of plants to freezing st...

High-fidelity simulation capability for virtual testing of seismic and acoustic sensors

NASA Astrophysics Data System (ADS)

Wilson, D. Keith; Moran, Mark L.; Ketcham, Stephen A.; Lacombe, James; Anderson, Thomas S.; Symons, Neill P.; Aldridge, David F.; Marlin, David H.; Collier, Sandra L.; Ostashev, Vladimir E.

2005-05-01

This paper describes development and application of a high-fidelity, seismic/acoustic simulation capability for battlefield sensors. The purpose is to provide simulated sensor data so realistic that they cannot be distinguished by experts from actual field data. This emerging capability provides rapid, low-cost trade studies of unattended ground sensor network configurations, data processing and fusion strategies, and signatures emitted by prototype vehicles. There are three essential components to the modeling: (1) detailed mechanical signature models for vehicles and walkers, (2) high-resolution characterization of the subsurface and atmospheric environments, and (3) state-of-the-art seismic/acoustic models for propagating moving-vehicle signatures through realistic, complex environments. With regard to the first of these components, dynamic models of wheeled and tracked vehicles have been developed to generate ground force inputs to seismic propagation models. Vehicle models range from simple, 2D representations to highly detailed, 3D representations of entire linked-track suspension systems. Similarly detailed models of acoustic emissions from vehicle engines are under development. The propagation calculations for both the seismics and acoustics are based on finite-difference, time-domain (FDTD) methodologies capable of handling complex environmental features such as heterogeneous geologies, urban structures, surface vegetation, and dynamic atmospheric turbulence. Any number of dynamic sources and virtual sensors may be incorporated into the FDTD model. The computational demands of 3D FDTD simulation over tactical distances require massively parallel computers. Several example calculations of seismic/acoustic wave propagation through complex atmospheric and terrain environments are shown.

Research on the key technologies of 3D spatial data organization and management for virtual building environments

NASA Astrophysics Data System (ADS)

Gong, Jun; Zhu, Qing

2006-10-01

As the special case of VGE in the fields of AEC (architecture, engineering and construction), Virtual Building Environment (VBE) has been broadly concerned. Highly complex, large-scale 3d spatial data is main bottleneck of VBE applications, so 3d spatial data organization and management certainly becomes the core technology for VBE. This paper puts forward 3d spatial data model for VBE, and the performance to implement it is very high. Inherent storage method of CAD data makes data redundant, and doesn't concern efficient visualization, which is a practical bottleneck to integrate CAD model, so An Efficient Method to Integrate CAD Model Data is put forward. Moreover, Since the 3d spatial indices based on R-tree are usually limited by their weakness of low efficiency due to the severe overlap of sibling nodes and the uneven size of nodes, a new node-choosing algorithm of R-tree are proposed.

Three-dimensional nanoscale imaging by plasmonic Brownian microscopy

NASA Astrophysics Data System (ADS)

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.

3D annotation and manipulation of medical anatomical structures

NASA Astrophysics Data System (ADS)

Vitanovski, Dime; Schaller, Christian; Hahn, Dieter; Daum, Volker; Hornegger, Joachim

2009-02-01

Although the medical scanners are rapidly moving towards a three-dimensional paradigm, the manipulation and annotation/labeling of the acquired data is still performed in a standard 2D environment. Editing and annotation of three-dimensional medical structures is currently a complex task and rather time-consuming, as it is carried out in 2D projections of the original object. A major problem in 2D annotation is the depth ambiguity, which requires 3D landmarks to be identified and localized in at least two of the cutting planes. Operating directly in a three-dimensional space enables the implicit consideration of the full 3D local context, which significantly increases accuracy and speed. A three-dimensional environment is as well more natural optimizing the user's comfort and acceptance. The 3D annotation environment requires the three-dimensional manipulation device and display. By means of two novel and advanced technologies, Wii Nintendo Controller and Philips 3D WoWvx display, we define an appropriate 3D annotation tool and a suitable 3D visualization monitor. We define non-coplanar setting of four Infrared LEDs with a known and exact position, which are tracked by the Wii and from which we compute the pose of the device by applying a standard pose estimation algorithm. The novel 3D renderer developed by Philips uses either the Z-value of a 3D volume, or it computes the depth information out of a 2D image, to provide a real 3D experience without having some special glasses. Within this paper we present a new framework for manipulation and annotation of medical landmarks directly in three-dimensional volume.

Scalable Multi-Platform Distribution of Spatial 3d Contents

NASA Astrophysics Data System (ADS)

Klimke, J.; Hagedorn, B.; Döllner, J.

2013-09-01

Virtual 3D city models provide powerful user interfaces for communication of 2D and 3D geoinformation. Providing high quality visualization of massive 3D geoinformation in a scalable, fast, and cost efficient manner is still a challenging task. Especially for mobile and web-based system environments, software and hardware configurations of target systems differ significantly. This makes it hard to provide fast, visually appealing renderings of 3D data throughout a variety of platforms and devices. Current mobile or web-based solutions for 3D visualization usually require raw 3D scene data such as triangle meshes together with textures delivered from server to client, what makes them strongly limited in terms of size and complexity of the models they can handle. In this paper, we introduce a new approach for provisioning of massive, virtual 3D city models on different platforms namely web browsers, smartphones or tablets, by means of an interactive map assembled from artificial oblique image tiles. The key concept is to synthesize such images of a virtual 3D city model by a 3D rendering service in a preprocessing step. This service encapsulates model handling and 3D rendering techniques for high quality visualization of massive 3D models. By generating image tiles using this service, the 3D rendering process is shifted from the client side, which provides major advantages: (a) The complexity of the 3D city model data is decoupled from data transfer complexity (b) the implementation of client applications is simplified significantly as 3D rendering is encapsulated on server side (c) 3D city models can be easily deployed for and used by a large number of concurrent users, leading to a high degree of scalability of the overall approach. All core 3D rendering techniques are performed on a dedicated 3D rendering server, and thin-client applications can be compactly implemented for various devices and platforms.

HyMoTrack: A Mobile AR Navigation System for Complex Indoor Environments.

PubMed

Gerstweiler, Georg; Vonach, Emanuel; Kaufmann, Hannes

2015-12-24

Navigating in unknown big indoor environments with static 2D maps is a challenge, especially when time is a critical factor. In order to provide a mobile assistant, capable of supporting people while navigating in indoor locations, an accurate and reliable localization system is required in almost every corner of the building. We present a solution to this problem through a hybrid tracking system specifically designed for complex indoor spaces, which runs on mobile devices like smartphones or tablets. The developed algorithm only uses the available sensors built into standard mobile devices, especially the inertial sensors and the RGB camera. The combination of multiple optical tracking technologies, such as 2D natural features and features of more complex three-dimensional structures guarantees the robustness of the system. All processing is done locally and no network connection is needed. State-of-the-art indoor tracking approaches use mainly radio-frequency signals like Wi-Fi or Bluetooth for localizing a user. In contrast to these approaches, the main advantage of the developed system is the capability of delivering a continuous 3D position and orientation of the mobile device with centimeter accuracy. This makes it usable for localization and 3D augmentation purposes, e.g. navigation tasks or location-based information visualization.

HyMoTrack: A Mobile AR Navigation System for Complex Indoor Environments

PubMed Central

Gerstweiler, Georg; Vonach, Emanuel; Kaufmann, Hannes

2015-01-01

Navigating in unknown big indoor environments with static 2D maps is a challenge, especially when time is a critical factor. In order to provide a mobile assistant, capable of supporting people while navigating in indoor locations, an accurate and reliable localization system is required in almost every corner of the building. We present a solution to this problem through a hybrid tracking system specifically designed for complex indoor spaces, which runs on mobile devices like smartphones or tablets. The developed algorithm only uses the available sensors built into standard mobile devices, especially the inertial sensors and the RGB camera. The combination of multiple optical tracking technologies, such as 2D natural features and features of more complex three-dimensional structures guarantees the robustness of the system. All processing is done locally and no network connection is needed. State-of-the-art indoor tracking approaches use mainly radio-frequency signals like Wi-Fi or Bluetooth for localizing a user. In contrast to these approaches, the main advantage of the developed system is the capability of delivering a continuous 3D position and orientation of the mobile device with centimeter accuracy. This makes it usable for localization and 3D augmentation purposes, e.g. navigation tasks or location-based information visualization. PMID:26712755

Generation of large scale urban environments to support advanced sensor and seeker simulation

NASA Astrophysics Data System (ADS)

Giuliani, Joseph; Hershey, Daniel; McKeown, David, Jr.; Willis, Carla; Van, Tan

2009-05-01

One of the key aspects for the design of a next generation weapon system is the need to operate in cluttered and complex urban environments. Simulation systems rely on accurate representation of these environments and require automated software tools to construct the underlying 3D geometry and associated spectral and material properties that are then formatted for various objective seeker simulation systems. Under an Air Force Small Business Innovative Research (SBIR) contract, we have developed an automated process to generate 3D urban environments with user defined properties. These environments can be composed from a wide variety of source materials, including vector source data, pre-existing 3D models, and digital elevation models, and rapidly organized into a geo-specific visual simulation database. This intermediate representation can be easily inspected in the visible spectrum for content and organization and interactively queried for accuracy. Once the database contains the required contents, it can then be exported into specific synthetic scene generation runtime formats, preserving the relationship between geometry and material properties. To date an exporter for the Irma simulation system developed and maintained by AFRL/Eglin has been created and a second exporter to Real Time Composite Hardbody and Missile Plume (CHAMP) simulation system for real-time use is currently being developed. This process supports significantly more complex target environments than previous approaches to database generation. In this paper we describe the capabilities for content creation for advanced seeker processing algorithms simulation and sensor stimulation, including the overall database compilation process and sample databases produced and exported for the Irma runtime system. We also discuss the addition of object dynamics and viewer dynamics within the visual simulation into the Irma runtime environment.

Quantitative real-time analysis of collective cancer invasion and dissemination

NASA Astrophysics Data System (ADS)

Ewald, Andrew J.

2015-05-01

A grand challenge in biology is to understand the cellular and molecular basis of tissue and organ level function in mammals. The ultimate goals of such efforts are to explain how organs arise in development from the coordinated actions of their constituent cells and to determine how molecularly regulated changes in cell behavior alter the structure and function of organs during disease processes. Two major barriers stand in the way of achieving these goals: the relative inaccessibility of cellular processes in mammals and the daunting complexity of the signaling environment inside an intact organ in vivo. To overcome these barriers, we have developed a suite of tissue isolation, three dimensional (3D) culture, genetic manipulation, nanobiomaterials, imaging, and molecular analysis techniques to enable the real-time study of cell biology within intact tissues in physiologically relevant 3D environments. This manuscript introduces the rationale for 3D culture, reviews challenges to optical imaging in these cultures, and identifies current limitations in the analysis of complex experimental designs that could be overcome with improved imaging, imaging analysis, and automated classification of the results of experimental interventions.

DHM simulation in virtual environments: a case-study on control room design.

PubMed

Zamberlan, M; Santos, V; Streit, P; Oliveira, J; Cury, R; Negri, T; Pastura, F; Guimarães, C; Cid, G

2012-01-01

This paper will present the workflow developed for the application of serious games in the design of complex cooperative work settings. The project was based on ergonomic studies and development of a control room among participative design process. Our main concerns were the 3D human virtual representation acquired from 3D scanning, human interaction, workspace layout and equipment designed considering ergonomics standards. Using Unity3D platform to design the virtual environment, the virtual human model can be controlled by users on dynamic scenario in order to evaluate the new work settings and simulate work activities. The results obtained showed that this virtual technology can drastically change the design process by improving the level of interaction between final users and, managers and human factors team.

A 3D Hydrodynamic Model for Heterogeneous Biofilms with Antimicrobial Persistence

DTIC Science & Technology

2014-01-01

antimicrobial agents, providing a useful tool for analyzing the mechanism of biofilm persistence to antimicrobial agents in an aqueous environment. The numerical...mecha- nism of biofilm persistence to antimicrobial agents in an aqueous environment. The numerical result also confirms that the periodic dosing...We model the biofilm together with its surrounding aqueous environment as a mixture of complex fluids. The biofilm is consisted of the biomass

3-D Technology Approaches for Biological Ecologies

NASA Astrophysics Data System (ADS)

Liu, Liyu; Austin, Robert; U. S-China Physical-Oncology Sciences Alliance (PS-OA) Team

Constructing three dimensional (3-D) landscapes is an inevitable issue in deep study of biological ecologies, because in whatever scales in nature, all of the ecosystems are composed by complex 3-D environments and biological behaviors. Just imagine if a 3-D technology could help complex ecosystems be built easily and mimic in vivo microenvironment realistically with flexible environmental controls, it will be a fantastic and powerful thrust to assist researchers for explorations. For years, we have been utilizing and developing different technologies for constructing 3-D micro landscapes for biophysics studies in in vitro. Here, I will review our past efforts, including probing cancer cell invasiveness with 3-D silicon based Tepuis, constructing 3-D microenvironment for cell invasion and metastasis through polydimethylsiloxane (PDMS) soft lithography, as well as explorations of optimized stenting positions for coronary bifurcation disease with 3-D wax printing and the latest home designed 3-D bio-printer. Although 3-D technologies is currently considered not mature enough for arbitrary 3-D micro-ecological models with easy design and fabrication, I hope through my talk, the audiences will be able to sense its significance and predictable breakthroughs in the near future. This work was supported by the State Key Development Program for Basic Research of China (Grant No. 2013CB837200), the National Natural Science Foundation of China (Grant No. 11474345) and the Beijing Natural Science Foundation (Grant No. 7154221).

Real-time 3D video compression for tele-immersive environments

NASA Astrophysics Data System (ADS)

Yang, Zhenyu; Cui, Yi; Anwar, Zahid; Bocchino, Robert; Kiyanclar, Nadir; Nahrstedt, Klara; Campbell, Roy H.; Yurcik, William

2006-01-01

Tele-immersive systems can improve productivity and aid communication by allowing distributed parties to exchange information via a shared immersive experience. The TEEVE research project at the University of Illinois at Urbana-Champaign and the University of California at Berkeley seeks to foster the development and use of tele-immersive environments by a holistic integration of existing components that capture, transmit, and render three-dimensional (3D) scenes in real time to convey a sense of immersive space. However, the transmission of 3D video poses significant challenges. First, it is bandwidth-intensive, as it requires the transmission of multiple large-volume 3D video streams. Second, existing schemes for 2D color video compression such as MPEG, JPEG, and H.263 cannot be applied directly because the 3D video data contains depth as well as color information. Our goal is to explore from a different angle of the 3D compression space with factors including complexity, compression ratio, quality, and real-time performance. To investigate these trade-offs, we present and evaluate two simple 3D compression schemes. For the first scheme, we use color reduction to compress the color information, which we then compress along with the depth information using zlib. For the second scheme, we use motion JPEG to compress the color information and run-length encoding followed by Huffman coding to compress the depth information. We apply both schemes to 3D videos captured from a real tele-immersive environment. Our experimental results show that: (1) the compressed data preserves enough information to communicate the 3D images effectively (min. PSNR > 40) and (2) even without inter-frame motion estimation, very high compression ratios (avg. > 15) are achievable at speeds sufficient to allow real-time communication (avg. ~ 13 ms per 3D video frame).

Exploring the Impact of Visual Complexity Levels in 3d City Models on the Accuracy of Individuals' Orientation and Cognitive Maps

NASA Astrophysics Data System (ADS)

Rautenbach, V.; Çöltekin, A.; Coetzee, S.

2015-08-01

In this paper we report results from a qualitative user experiment (n=107) designed to contribute to understanding the impact of various levels of complexity (mainly based on levels of detail, i.e., LoD) in 3D city models, specifically on the participants' orientation and cognitive (mental) maps. The experiment consisted of a number of tasks motivated by spatial cognition theory where participants (among other things) were given orientation tasks, and in one case also produced sketches of a path they `travelled' in a virtual environment. The experiments were conducted in groups, where individuals provided responses on an answer sheet. The preliminary results based on descriptive statistics and qualitative sketch analyses suggest that very little information (i.e., a low LoD model of a smaller area) might have a negative impact on the accuracy of cognitive maps constructed based on a virtual experience. Building an accurate cognitive map is an inherently desired effect of the visualizations in planning tasks, thus the findings are important for understanding how to develop better-suited 3D visualizations such as 3D city models. In this study, we specifically discuss the suitability of different levels of visual complexity for development planning (urban planning), one of the domains where 3D city models are most relevant.

Vinculin is required for cell polarization, migration, and extracellular matrix remodeling in 3D collagen.

PubMed

Thievessen, Ingo; Fakhri, Nikta; Steinwachs, Julian; Kraus, Viola; McIsaac, R Scott; Gao, Liang; Chen, Bi-Chang; Baird, Michelle A; Davidson, Michael W; Betzig, Eric; Oldenbourg, Rudolf; Waterman, Clare M; Fabry, Ben

2015-11-01

Vinculin is filamentous (F)-actin-binding protein enriched in integrin-based adhesions to the extracellular matrix (ECM). Whereas studies in 2-dimensional (2D) tissue culture models have suggested that vinculin negatively regulates cell migration by promoting cytoskeleton-ECM coupling to strengthen and stabilize adhesions, its role in regulating cell migration in more physiologic, 3-dimensional (3D) environments is unclear. To address the role of vinculin in 3D cell migration, we analyzed the morphodynamics, migration, and ECM remodeling of primary murine embryonic fibroblasts (MEFs) with cre/loxP-mediated vinculin gene disruption in 3D collagen I cultures. We found that vinculin promoted 3D cell migration by increasing directional persistence. Vinculin was necessary for persistent cell protrusion, cell elongation, and stable cell orientation in 3D collagen, but was dispensable for lamellipodia formation, suggesting that vinculin-mediated cell adhesion to the ECM is needed to convert actin-based cell protrusion into persistent cell shape change and migration. Consistent with this finding, vinculin was necessary for efficient traction force generation in 3D collagen without affecting myosin II activity and promoted 3D collagen fiber alignment and macroscopical gel contraction. Our results suggest that vinculin promotes directionally persistent cell migration and tension-dependent ECM remodeling in complex 3D environments by increasing cell-ECM adhesion and traction force generation. © FASEB.

High-Resolution Imaged-Based 3D Reconstruction Combined with X-Ray CT Data Enables Comprehensive Non-Destructive Documentation and Targeted Research of Astromaterials

NASA Technical Reports Server (NTRS)

Blumenfeld, E. H.; Evans, C. A.; Oshel, E. R.; Liddle, D. A.; Beaulieu, K.; Zeigler, R. A.; Righter, K.; Hanna, R. D.; Ketcham, R. A.

2014-01-01

Providing web-based data of complex and sensitive astromaterials (including meteorites and lunar samples) in novel formats enhances existing preliminary examination data on these samples and supports targeted sample requests and analyses. We have developed and tested a rigorous protocol for collecting highly detailed imagery of meteorites and complex lunar samples in non-contaminating environments. These data are reduced to create interactive 3D models of the samples. We intend to provide these data as they are acquired on NASA's Astromaterials Acquisition and Curation website at http://curator.jsc.nasa.gov/.

Evolution Process and Structural Analysis of Precambrian Jirisan Metamorphic and Sancheong Anorthosite Complexes in the Jirisan Province, Yeongnam Massif, Korea

NASA Astrophysics Data System (ADS)

Kang, J. H.; Lee, D. S.

2016-12-01

The Jirisan metamorphic complex consists mainly of schist, blastoporphyritic granite gneiss, granitic gneiss, leucocratic gneiss, biotite gneiss, banded gneiss, migmatitic gneiss and granite gneiss. The Paleoproterozoic (1.87 1.79 Ga) Sancheong anorthosite complex, which intrude it, is classified into massive-type and foliation-type Sancheong anorthosite, Fe-Ti ore body, and mafic granulite which were formed from the multiple fractionation and polybaric crystallization of the coeval and cogenetic magma. These complexes went at least through three times of ductile deformation during Early Proterozoic Late Paleozoic. The D1 deformation formed sheath or "A" type folds and its characteristic orientation was uncertain due to the intensive multi-deformation superimposed after that. The D2 deformation occurred under the EW- or WNW-directed tectonic compression, and formed a regional NS or NNE trend of isoclinal and intrafolial folds and an extensive ductile shear zone accompanied by mylonitization. The D3 deformation occurred under the NS- or NNW-directed tectonic compression environment, and formed an EW or ENE trend of open and tight folds and a partial semibrittle shear zone accompanied by mylonitization, and rearranged the NS-trend pre-D3 structural elements into (E)NE or (W)NW direction. The D2 deformation generally increases from the center toward the margin of Sancheong anorthosite complex but is more intensive in the eastern than western parts of Sancheong anorthosite complex. While the D3 deformation is inversely more intensive in the its western than eastern parts. The D2 and D3 deformations are closely related to the distribution features of Sancheong anorthosite complex. These three tectonic events are expected to give important information in understanding and reconstructing the tectonic movement after the formation of Columbia Supercontinent as well as the present NS-trend tectonic frame of the Jirisan province of the Yeongnam massif, the Korean Peninsula.

Human factors guidelines for applications of 3D perspectives: a literature review

NASA Astrophysics Data System (ADS)

Dixon, Sharon; Fitzhugh, Elisabeth; Aleva, Denise

2009-05-01

Once considered too processing-intense for general utility, application of the third dimension to convey complex information is facilitated by the recent proliferation of technological advancements in computer processing, 3D displays, and 3D perspective (2.5D) renderings within a 2D medium. The profusion of complex and rapidly-changing dynamic information being conveyed in operational environments has elevated interest in possible military applications of 3D technologies. 3D can be a powerful mechanism for clearer information portrayal, facilitating rapid and accurate identification of key elements essential to mission performance and operator safety. However, implementation of 3D within legacy systems can be costly, making integration prohibitive. Therefore, identifying which tasks may benefit from 3D or 2.5D versus simple 2D visualizations is critical. Unfortunately, there is no "bible" of human factors guidelines for usability optimization of 2D, 2.5D, or 3D visualizations nor for determining which display best serves a particular application. Establishing such guidelines would provide an invaluable tool for designers and operators. Defining issues common to each will enhance design effectiveness. This paper presents the results of an extensive review of open source literature addressing 3D information displays, with particular emphasis on comparison of true 3D with 2D and 2.5D representations and their utility for military tasks. Seventy-five papers are summarized, highlighting militarily relevant applications of 3D visualizations and 2.5D perspective renderings. Based on these findings, human factors guidelines for when and how to use these visualizations, along with recommendations for further research are discussed.

Oblique Photogrammetry Supporting 3d Urban Reconstruction of Complex Scenarios

NASA Astrophysics Data System (ADS)

Toschi, I.; Ramos, M. M.; Nocerino, E.; Menna, F.; Remondino, F.; Moe, K.; Poli, D.; Legat, K.; Fassi, F.

2017-05-01

Accurate 3D city models represent an important source of geospatial information to support various "smart city" applications, such as space management, energy assessment, 3D cartography, noise and pollution mapping as well as disaster management. Even though remarkable progress has been made in recent years, there are still many open issues, especially when it comes to the 3D modelling of complex urban scenarios like historical and densely-built city centres featuring narrow streets and non-conventional building shapes. Most approaches introduce strong building priors/constraints on symmetry and roof typology that penalize urban environments having high variations of roof shapes. Furthermore, although oblique photogrammetry is rapidly maturing, the use of slanted views for façade reconstruction is not completely included in the reconstruction pipeline of state-of-the-art software. This paper aims to investigate state-of-the-art methods for 3D building modelling in complex urban scenarios with the support of oblique airborne images. A reconstruction approach based on roof primitives fitting is tested. Oblique imagery is then exploited to support the manual editing of the generated building models. At the same time, mobile mapping data are collected at cm resolution and then integrated with the aerial ones. All approaches are tested on the historical city centre of Bergamo (Italy).

3D stromal tissue equivalent affects intestinal epithelium morphogenesis in vitro.

PubMed

De Gregorio, Vincenza; Imparato, Giorgia; Urciuolo, Francesco; Netti, Paolo A

2018-04-01

Current in vitro models of human intestine commonly fail to mimic the complex intestinal functions and features required for drug development and disease research. Here, we deeply investigate the interaction existing between epithelium and the underneath stroma, and its role in the epithelium morphogenesis. We cultured human intestinal subepithelial myofibroblasts (ISEMFs) in two different 3D configurations: 3D-collagen gel equivalent (3D-CGE) and 3D cell-synthetized stromal equivalent (3D-CSSE). The 3D-CGEs were obtained by means of the traditional collagen-based cell technique and the 3D-CSSE were obtained by bottom-up tissue engineering strategy. The biophysical properties of both 3D models with regard to cell growth and composition (via histological analysis, immunofluorescence, and multiphoton imaging) were assessed. Then, human colorectal adenocarcinoma cell line (CaCo-2) was cultured on both the 3D constructs in order to produce the intestinal model. We identified higher levels of matrix-associated proteins from ISEMFs cultured in 3D-CSSE compared to 3D-CGE. Furthermore, multiphoton investigation revealed differences in the collagen network architecture in both models. At last, the more physiologically relevant stromal environment of the 3D-CSSE drove the CaCo-2 cell differentiation toward the four different type of intestinal epithelial cells (absorptive, mucus-secretory, enteroendocrine, and Paneth) phenotype and promotes, in contrast to the 3D-CGE, the production of the basement membrane. Taken together, these results highlight a fundamental role of the 3D stromal environment in addressing a correct epithelium morphogenesis as well as epithelial-stromal interface establishment. © 2017 Wiley Periodicals, Inc.

Biomimetic three-dimensional tissue models for advanced high-throughput drug screening

PubMed Central

Nam, Ki-Hwan; Smith, Alec S.T.; Lone, Saifullah; Kwon, Sunghoon; Kim, Deok-Ho

2015-01-01

Most current drug screening assays used to identify new drug candidates are 2D cell-based systems, even though such in vitro assays do not adequately recreate the in vivo complexity of 3D tissues. Inadequate representation of the human tissue environment during a preclinical test can result in inaccurate predictions of compound effects on overall tissue functionality. Screening for compound efficacy by focusing on a single pathway or protein target, coupled with difficulties in maintaining long-term 2D monolayers, can serve to exacerbate these issues when utilizing such simplistic model systems for physiological drug screening applications. Numerous studies have shown that cell responses to drugs in 3D culture are improved from those in 2D, with respect to modeling in vivo tissue functionality, which highlights the advantages of using 3D-based models for preclinical drug screens. In this review, we discuss the development of microengineered 3D tissue models which accurately mimic the physiological properties of native tissue samples, and highlight the advantages of using such 3D micro-tissue models over conventional cell-based assays for future drug screening applications. We also discuss biomimetic 3D environments, based-on engineered tissues as potential preclinical models for the development of more predictive drug screening assays for specific disease models. PMID:25385716

Microfluidic neurite guidance to study structure-function relationships in topologically-complex population-based neural networks.

PubMed

Honegger, Thibault; Thielen, Moritz I; Feizi, Soheil; Sanjana, Neville E; Voldman, Joel

2016-06-22

The central nervous system is a dense, layered, 3D interconnected network of populations of neurons, and thus recapitulating that complexity for in vitro CNS models requires methods that can create defined topologically-complex neuronal networks. Several three-dimensional patterning approaches have been developed but none have demonstrated the ability to control the connections between populations of neurons. Here we report a method using AC electrokinetic forces that can guide, accelerate, slow down and push up neurites in un-modified collagen scaffolds. We present a means to create in vitro neural networks of arbitrary complexity by using such forces to create 3D intersections of primary neuronal populations that are plated in a 2D plane. We report for the first time in vitro basic brain motifs that have been previously observed in vivo and show that their functional network is highly decorrelated to their structure. This platform can provide building blocks to reproduce in vitro the complexity of neural circuits and provide a minimalistic environment to study the structure-function relationship of the brain circuitry.

Microfluidic neurite guidance to study structure-function relationships in topologically-complex population-based neural networks

NASA Astrophysics Data System (ADS)

Honegger, Thibault; Thielen, Moritz I.; Feizi, Soheil; Sanjana, Neville E.; Voldman, Joel

2016-06-01

The central nervous system is a dense, layered, 3D interconnected network of populations of neurons, and thus recapitulating that complexity for in vitro CNS models requires methods that can create defined topologically-complex neuronal networks. Several three-dimensional patterning approaches have been developed but none have demonstrated the ability to control the connections between populations of neurons. Here we report a method using AC electrokinetic forces that can guide, accelerate, slow down and push up neurites in un-modified collagen scaffolds. We present a means to create in vitro neural networks of arbitrary complexity by using such forces to create 3D intersections of primary neuronal populations that are plated in a 2D plane. We report for the first time in vitro basic brain motifs that have been previously observed in vivo and show that their functional network is highly decorrelated to their structure. This platform can provide building blocks to reproduce in vitro the complexity of neural circuits and provide a minimalistic environment to study the structure-function relationship of the brain circuitry.

Partonomies for interactive explorable 3D-models of anatomy.

PubMed

Schubert, R; Höhne, K H

1998-01-01

We introduce a concept to model subtle part-whole-semantics for the use with interactive 3d-models of human anatomy. Similar to experiences with modeling partonomies for physical artifacts like machines or buildings we found one unique part-whole-relation to be insufficient to represent anatomical reality. This claim will be illustrated with anatomical examples. According to the requirements these examples demand, a semantic classification of part-whole-relations is introduced. Initial results in modeling anatomical partonomies for a 3d-visualization environment proved this approach to be an promising way to represent anatomy and to enable powerful complex inferences.

Disentangling the intragroup HI in Compact Groups of galaxies by means of X3D visualization

NASA Astrophysics Data System (ADS)

Verdes-Montenegro, Lourdes; Vogt, Frederic; Aubery, Claire; Duret, Laetitie; Garrido, Julián; Sánchez, Susana; Yun, Min S.; Borthakur, Sanchayeeta; Hess, Kelley; Cluver, Michelle; Del Olmo, Ascensión; Perea, Jaime

2017-03-01

As an extreme kind of environment, Hickson Compact groups (HCGs) have shown to be very complex systems. HI-VLA observations revealed an intrincated network of HI tails and bridges, tracing pre-processing through extreme tidal interactions. We found HCGs to show a large HI deficiency supporting an evolutionary sequence where gas-rich groups transform via tidal interactions and ISM (interstellar medium) stripping into gas-poor systems. We detected as well a diffuse HI component in the groups, increasing with evolutionary phase, although with uncertain distribution. The complex net of detected HI as observed with the VLA seems hence so puzzling as the missing one. In this talk we revisit the existing VLA information on the HI distribution and kinematics of HCGs by means of X3D visualization. X3D constitutes a powerful tool to extract the most from HI data cubes and a mean of simplifying and easing the access to data visualization and publication via three-dimensional (3-D) diagrams.

A nodal discontinuous Galerkin approach to 3-D viscoelastic wave propagation in complex geological media

NASA Astrophysics Data System (ADS)

Lambrecht, L.; Lamert, A.; Friederich, W.; Möller, T.; Boxberg, M. S.

2018-03-01

A nodal discontinuous Galerkin (NDG) approach is developed and implemented for the computation of viscoelastic wavefields in complex geological media. The NDG approach combines unstructured tetrahedral meshes with an element-wise, high-order spatial interpolation of the wavefield based on Lagrange polynomials. Numerical fluxes are computed from an exact solution of the heterogeneous Riemann problem. Our implementation offers capabilities for modelling viscoelastic wave propagation in 1-D, 2-D and 3-D settings of very different spatial scale with little logistical overhead. It allows the import of external tetrahedral meshes provided by independent meshing software and can be run in a parallel computing environment. Computation of adjoint wavefields and an interface for the computation of waveform sensitivity kernels are offered. The method is validated in 2-D and 3-D by comparison to analytical solutions and results from a spectral element method. The capabilities of the NDG method are demonstrated through a 3-D example case taken from tunnel seismics which considers high-frequency elastic wave propagation around a curved underground tunnel cutting through inclined and faulted sedimentary strata. The NDG method was coded into the open-source software package NEXD and is available from GitHub.

Structure of a novel exopolysaccharide produced by Burkholderia vietnamiensis, a cystic fibrosis opportunistic pathogen.

PubMed

Cescutti, Paola; Cuzzi, Bruno; Herasimenka, Yury; Rizzo, Roberto

2013-04-15

Burkholderia vietnamiensis belongs to the Burkholderia cepacia complex and is an opportunistic pathogen for cystic fibrosis patients. As many other Burkholderia species, it has a mucoide phenotype, producing abundant exopolysaccharide. In general, polysaccharides contribute to bacterial survival in a hostile environment, are recognised as virulence factors and as important components in biofilm formation. The primary structure of the exopolysaccharide produced by B. vietnamiensis LMG 10929 was determined mainly by use of 1D and 2D NMR spectroscopy and ESI mass spectrometry. The polymer consists of the trisaccharidic backbone 3)-β-D-Glcp-(1→4)-α-D-Glcp-(1→3)-α-L-Fucp-(1→ with the side chain α-D-Glcp-(1→4)-α-D-GlcAp-(1→3)-α-L-Fucp-(1→ linked to C-3 of the α-D-Glcp residue. The polysaccharide also bears acetyl substituents on about 20% of its repeating units and on at least two different positions. The presence of fucose residues is a novel structural feature among the exopolysaccharides produced by species of the B. cepacia complex. Copyright © 2013 Elsevier Ltd. All rights reserved.

Three-dimensional macro-structures of two-dimensional nanomaterials.

PubMed

Shehzad, Khurram; Xu, Yang; Gao, Chao; Duan, Xiangfeng

2016-10-21

If two-dimensional (2D) nanomaterials are ever to be utilized as components of practical, macroscopic devices on a large scale, there is a complementary need to controllably assemble these 2D building blocks into more sophisticated and hierarchical three-dimensional (3D) architectures. Such a capability is key to design and build complex, functional devices with tailored properties. This review provides a comprehensive overview of the various experimental strategies currently used to fabricate the 3D macro-structures of 2D nanomaterials. Additionally, various approaches for the decoration of the 3D macro-structures with organic molecules, polymers, and inorganic materials are reviewed. Finally, we discuss the applications of 3D macro-structures, especially in the areas of energy, environment, sensing, and electronics, and describe the existing challenges and the outlook for this fast emerging field.

Cognitive Aspects of Collaboration in 3d Virtual Environments

NASA Astrophysics Data System (ADS)

Juřík, V.; Herman, L.; Kubíček, P.; Stachoň, Z.; Šašinka, Č.

2016-06-01

Human-computer interaction has entered the 3D era. The most important models representing spatial information — maps — are transferred into 3D versions regarding the specific content to be displayed. Virtual worlds (VW) become promising area of interest because of possibility to dynamically modify content and multi-user cooperation when solving tasks regardless to physical presence. They can be used for sharing and elaborating information via virtual images or avatars. Attractiveness of VWs is emphasized also by possibility to measure operators' actions and complex strategies. Collaboration in 3D environments is the crucial issue in many areas where the visualizations are important for the group cooperation. Within the specific 3D user interface the operators' ability to manipulate the displayed content is explored regarding such phenomena as situation awareness, cognitive workload and human error. For such purpose, the VWs offer a great number of tools for measuring the operators' responses as recording virtual movement or spots of interest in the visual field. Study focuses on the methodological issues of measuring the usability of 3D VWs and comparing them with the existing principles of 2D maps. We explore operators' strategies to reach and interpret information regarding the specific type of visualization and different level of immersion.

Semi-3D dosimetry of high dose rate brachytherapy using a novel Gafchromic EBT3 film-array water phantom

NASA Astrophysics Data System (ADS)

Palmer, A. L.; Nisbet, A.; Bradley, D. A.

2013-06-01

There is a need to modernise clinical brachytherapy dosimetry measurement beyond traditional point dose verification to enable appropriate quality control within 3D treatment environments. This is to keep pace with the 3D clinical and planning approaches which often include significant patient-specific optimisation away from 'standard loading patterns'. A multi-dimension measurement system is required to provide assurance of the complex 3D dose distributions, to verify equipment performance, and to enable quality audits. However, true 3D dose measurements around brachytherapy applicators are often impractical due to their complex shapes and the requirement for close measurement distances. A solution utilising an array of radiochromic film (Gafchromic EBT3) positioned within a water filled phantom is presented. A calibration function for the film has been determined over 0 to 90Gy dose range using three colour channel analysis (FilmQAPro software). Film measurements of the radial dose from a single HDR source agree with TPS and Monte Carlo calculations within 5 % up to 50 mm from the source. Film array measurements of the dose distribution around a cervix applicator agree with TPS calculations generally within 4 mm distance to agreement. The feasibility of film array measurements for semi-3D dosimetry in clinical HDR applications is demonstrated.

Toward the establishment of design guidelines for effective 3D perspective interfaces

NASA Astrophysics Data System (ADS)

Fitzhugh, Elisabeth; Dixon, Sharon; Aleva, Denise; Smith, Eric; Ghrayeb, Joseph; Douglas, Lisa

2009-05-01

The propagation of information operation technologies, with correspondingly vast amounts of complex network information to be conveyed, significantly impacts operator workload. Information management research is rife with efforts to develop schemes to aid operators to identify, review, organize, and retrieve the wealth of available data. Data may take on such distinct forms as intelligence libraries, logistics databases, operational environment models, or network topologies. Increased use of taxonomies and semantic technologies opens opportunities to employ network visualization as a display mechanism for diverse information aggregations. The broad applicability of network visualizations is still being tested, but in current usage, the complexity of densely populated abstract networks suggests the potential utility of 3D. Employment of 2.5D in network visualization, using classic perceptual cues, creates a 3D experience within a 2D medium. It is anticipated that use of 3D perspective (2.5D) will enhance user ability to visually inspect large, complex, multidimensional networks. Current research for 2.5D visualizations demonstrates that display attributes, including color, shape, size, lighting, atmospheric effects, and shadows, significantly impact operator experience. However, guidelines for utilization of attributes in display design are limited. This paper discusses pilot experimentation intended to identify potential problem areas arising from these cues and determine how best to optimize perceptual cue settings. Development of optimized design guidelines will ensure that future experiments, comparing network displays with other visualizations, are not confounded or impeded by suboptimal attribute characterization. Current experimentation is anticipated to support development of cost-effective, visually effective methods to implement 3D in military applications.

A collaborative virtual reality environment for neurosurgical planning and training.

PubMed

Kockro, Ralf A; Stadie, Axel; Schwandt, Eike; Reisch, Robert; Charalampaki, Cleopatra; Ng, Ivan; Yeo, Tseng Tsai; Hwang, Peter; Serra, Luis; Perneczky, Axel

2007-11-01

We have developed a highly interactive virtual environment that enables collaborative examination of stereoscopic three-dimensional (3-D) medical imaging data for planning, discussing, or teaching neurosurgical approaches and strategies. The system consists of an interactive console with which the user manipulates 3-D data using hand-held and tracked devices within a 3-D virtual workspace and a stereoscopic projection system. The projection system displays the 3-D data on a large screen while the user is working with it. This setup allows users to interact intuitively with complex 3-D data while sharing this information with a larger audience. We have been using this system on a routine clinical basis and during neurosurgical training courses to collaboratively plan and discuss neurosurgical procedures with 3-D reconstructions of patient-specific magnetic resonance and computed tomographic imaging data or with a virtual model of the temporal bone. Working collaboratively with the 3-D information of a large, interactive, stereoscopic projection provides an unambiguous way to analyze and understand the anatomic spatial relationships of different surgical corridors. In our experience, the system creates a unique forum for open and precise discussion of neurosurgical approaches. We believe the system provides a highly effective way to work with 3-D data in a group, and it significantly enhances teaching of neurosurgical anatomy and operative strategies.

Synthesis, structural characterization, photo-physical and magnetic properties of cobalt salphen pseudo halide complexes showing meta-magnetic ordering

NASA Astrophysics Data System (ADS)

Nassief, A. R.; Abdel-Hafiez, M.; Hassen, A.; Khalil, A. S. G.; Saber, M. R.

2018-04-01

The solvo-thermal syntheses of [(CoSalphen)2Co (SCN)2]n (1), CoSalphen(NH3)(N3)(2), Na[CoIIIsalphen(N3)2](3), Na[CoIIIsalen(N3)2](4) and CoIIIsalen(NH3)(N3) (5) {salphen = N,N'-o-phenylene-bis(salicylideneimine)} are reported. The structural studies using X-ray diffraction measurements revealed that 1 crystalizes in a monoclinic C2/c space group. Two cobalt (II) metal centers in penta-coordinated and octahedral local coordination environments are bridged via alternating O and μ1,3 SCN bridges resulting in a novel 2D layered coordination polymer. Compound 2 is a trivalent mononuclear cobalt azido complex with an octahedral coordination environment. The magnetic investigations of 1 revealed ferromagnetic coupling (J = +49.1 cm-1) and meta-magnetic ordering. Time resolved photoluminescence studies of the complexes showed excited state lifetimes of (τ1 = 0.4675 ns, τ2 = 5.23 ns) for 1 and (τ1 = 0.5078 ns, τ2 = 6.79 ns) for 2.

Sci-Vis Framework

DOE Office of Scientific and Technical Information (OSTI.GOV)

Arthur Bleeker, PNNL

2015-03-11

SVF is a full featured OpenGL 3d framework that allows for rapid creation of complex visualizations. The SVF framework handles much of the lifecycle and complex tasks required for a 3d visualization. Unlike a game framework SVF was designed to use fewer resources, work well in a windowed environment, and only render when necessary. The scene also takes advantage of multiple threads to free up the UI thread as much as possible. Shapes (actors) in the scene are created by adding or removing functionality (through support objects) during runtime. This allows a highly flexible and dynamic means of creating highlymore » complex actors without the code complexity (it also helps overcome the lack of multiple inheritance in Java.) All classes are highly customizable and there are abstract classes which are intended to be subclassed to allow a developer to create more complex and highly performant actors. There are multiple demos included in the framework to help the developer get started and shows off nearly all of the functionality. Some simple shapes (actors) are already created for you such as text, bordered text, radial text, text area, complex paths, NURBS paths, cube, disk, grid, plane, geometric shapes, and volumetric area. It also comes with various camera types for viewing that can be dragged, zoomed, and rotated. Picking or selecting items in the scene can be accomplished in various ways depending on your needs (raycasting or color picking.) The framework currently has functionality for tooltips, animation, actor pools, color gradients, 2d physics, text, 1d/2d/3d textures, children, blending, clipping planes, view frustum culling, custom shaders, and custom actor states« less

Procedural 3d Modelling for Traditional Settlements. The Case Study of Central Zagori

NASA Astrophysics Data System (ADS)

Kitsakis, D.; Tsiliakou, E.; Labropoulos, T.; Dimopoulou, E.

2017-02-01

Over the last decades 3D modelling has been a fast growing field in Geographic Information Science, extensively applied in various domains including reconstruction and visualization of cultural heritage, especially monuments and traditional settlements. Technological advances in computer graphics, allow for modelling of complex 3D objects achieving high precision and accuracy. Procedural modelling is an effective tool and a relatively novel method, based on algorithmic modelling concept. It is utilized for the generation of accurate 3D models and composite facade textures from sets of rules which are called Computer Generated Architecture grammars (CGA grammars), defining the objects' detailed geometry, rather than altering or editing the model manually. In this paper, procedural modelling tools have been exploited to generate the 3D model of a traditional settlement in the region of Central Zagori in Greece. The detailed geometries of 3D models derived from the application of shape grammars on selected footprints, and the process resulted in a final 3D model, optimally describing the built environment of Central Zagori, in three levels of Detail (LoD). The final 3D scene was exported and published as 3D web-scene which can be viewed with 3D CityEngine viewer, giving a walkthrough the whole model, same as in virtual reality or game environments. This research work addresses issues regarding textures' precision, LoD for 3D objects and interactive visualization within one 3D scene, as well as the effectiveness of large scale modelling, along with the benefits and drawbacks that derive from procedural modelling techniques in the field of cultural heritage and more specifically on 3D modelling of traditional settlements.

Sculpting 3D worlds with music: advanced texturing techniques

NASA Astrophysics Data System (ADS)

Greuel, Christian; Bolas, Mark T.; Bolas, Niko; McDowall, Ian E.

1996-04-01

Sound within the virtual environment is often considered to be secondary to the graphics. In a typical scenario, either audio cues are locally associated with specific 3D objects or a general aural ambiance is supplied in order to alleviate the sterility of an artificial experience. This paper discusses a completely different approach, in which cues are extracted from live or recorded music in order to create geometry and control object behaviors within a computer- generated environment. Advanced texturing techniques used to generate complex stereoscopic images are also discussed. By analyzing music for standard audio characteristics such as rhythm and frequency, information is extracted and repackaged for processing. With the Soundsculpt Toolkit, this data is mapped onto individual objects within the virtual environment, along with one or more predetermined behaviors. Mapping decisions are implemented with a user definable schedule and are based on the aesthetic requirements of directors and designers. This provides for visually active, immersive environments in which virtual objects behave in real-time correlation with the music. The resulting music-driven virtual reality opens up several possibilities for new types of artistic and entertainment experiences, such as fully immersive 3D `music videos' and interactive landscapes for live performance.

Bioprinting is changing regenerative medicine forever.

PubMed

Collins, Scott Forrest

2014-12-01

3D printing, or solid freeform fabrication, applied to regenerative medicine brings technologies from several industries together to help solve unique challenges in both basic science and tissue engineering. By more finely organizing cells and supporting structures precisely in 3D space, we will gain critical knowledge of cell-cell communications and cell-environment interactions. As we increase the scale, we will move toward complex tissue and organ structures where several cell phenotypes will functionally and structurally interact, thus recapitulating the form and function of native tissues and organs.

Generating Contextual Descriptions of Virtual Reality (VR) Spaces

NASA Astrophysics Data System (ADS)

Olson, D. M.; Zaman, C. H.; Sutherland, A.

2017-12-01

Virtual reality holds great potential for science communication, education, and research. However, interfaces for manipulating data and environments in virtual worlds are limited and idiosyncratic. Furthermore, speech and vision are the primary modalities by which humans collect information about the world, but the linking of visual and natural language domains is a relatively new pursuit in computer vision. Machine learning techniques have been shown to be effective at image and speech classification, as well as at describing images with language (Karpathy 2016), but have not yet been used to describe potential actions. We propose a technique for creating a library of possible context-specific actions associated with 3D objects in immersive virtual worlds based on a novel dataset generated natively in virtual reality containing speech, image, gaze, and acceleration data. We will discuss the design and execution of a user study in virtual reality that enabled the collection and the development of this dataset. We will also discuss the development of a hybrid machine learning algorithm linking vision data with environmental affordances in natural language. Our findings demonstrate that it is possible to develop a model which can generate interpretable verbal descriptions of possible actions associated with recognized 3D objects within immersive VR environments. This suggests promising applications for more intuitive user interfaces through voice interaction within 3D environments. It also demonstrates the potential to apply vast bodies of embodied and semantic knowledge to enrich user interaction within VR environments. This technology would allow for applications such as expert knowledge annotation of 3D environments, complex verbal data querying and object manipulation in virtual spaces, and computer-generated, dynamic 3D object affordances and functionality during simulations.

Experimenter's Laboratory for Visualized Interactive Science

NASA Technical Reports Server (NTRS)

Hansen, Elaine R.; Rodier, Daniel R.; Klemp, Marjorie K.

1994-01-01

ELVIS (Experimenter's Laboratory for Visualized Interactive Science) is an interactive visualization environment that enables scientists, students, and educators to visualize and analyze large, complex, and diverse sets of scientific data. It accomplishes this by presenting the data sets as 2-D, 3-D, color, stereo, and graphic images with movable and multiple light sources combined with displays of solid-surface, contours, wire-frame, and transparency. By simultaneously rendering diverse data sets acquired from multiple sources, formats, and resolutions and by interacting with the data through an intuitive, direct-manipulation interface, ELVIS provides an interactive and responsive environment for exploratory data analysis.

Extension of an iterative closest point algorithm for simultaneous localization and mapping in corridor environments

NASA Astrophysics Data System (ADS)

Yue, Haosong; Chen, Weihai; Wu, Xingming; Wang, Jianhua

2016-03-01

Three-dimensional (3-D) simultaneous localization and mapping (SLAM) is a crucial technique for intelligent robots to navigate autonomously and execute complex tasks. It can also be applied to shape measurement, reverse engineering, and many other scientific or engineering fields. A widespread SLAM algorithm, named KinectFusion, performs well in environments with complex shapes. However, it cannot handle translation uncertainties well in highly structured scenes. This paper improves the KinectFusion algorithm and makes it competent in both structured and unstructured environments. 3-D line features are first extracted according to both color and depth data captured by Kinect sensor. Then the lines in the current data frame are matched with the lines extracted from the entire constructed world model. Finally, we fuse the distance errors of these line-pairs into the standard KinectFusion framework and estimate sensor poses using an iterative closest point-based algorithm. Comparative experiments with the KinectFusion algorithm and one state-of-the-art method in a corridor scene have been done. The experimental results demonstrate that after our improvement, the KinectFusion algorithm can also be applied to structured environments and has higher accuracy. Experiments on two open access datasets further validated our improvements.

Biomaterials for 4D stem cell culture

PubMed Central

Hilderbrand, Amber M.; Ovadia, Elisa M.; Rehmann, Matthew S.; Kharkar, Prathamesh M.; Guo, Chen; Kloxin, April M.

2017-01-01

Stem cells reside in complex three-dimensional (3D) environments within the body that change with time, promoting various cellular functions and processes such as migration and differentiation. These complex changes in the surrounding environment dictate cell fate yet, until recently, have been challenging to mimic within cell culture systems. Hydrogel-based biomaterials are well suited to mimic aspects of these in vivo environments, owing to their high water content, soft tissue-like elasticity, and often-tunable biochemical content. Further, hydrogels can be engineered to achieve changes in matrix properties over time to better mimic dynamic native microenvironments for probing and directing stem cell function and fate. This review will focus on techniques to form hydrogel-based biomaterials and modify their properties in time during cell culture using select addition reactions, cleavage reactions, or non-covalent interactions. Recent applications of these techniques for the culture of stem cells in four dimensions (i.e., in three dimensions with changes over time) also will be discussed for studying essential stem cell processes. PMID:28717344

Sampling-Based Coverage Path Planning for Complex 3D Structures

DTIC Science & Technology

2012-09-01

one such task, in which a single robot must sweep its end effector over the entirety of a known workspace. For two-dimensional environments, optimal...structures. First, we introduce a new algorithm for planning feasible coverage paths. It is more computationally efficient in problems of complex geometry...iteratively shortens and smooths a feasible coverage path; robot configurations are adjusted without violating any coverage con- straints. Third, we propose

Network dynamics of 3D engineered neuronal cultures: a new experimental model for in-vitro electrophysiology.

PubMed

Frega, Monica; Tedesco, Mariateresa; Massobrio, Paolo; Pesce, Mattia; Martinoia, Sergio

2014-06-30

Despite the extensive use of in-vitro models for neuroscientific investigations and notwithstanding the growing field of network electrophysiology, all studies on cultured cells devoted to elucidate neurophysiological mechanisms and computational properties, are based on 2D neuronal networks. These networks are usually grown onto specific rigid substrates (also with embedded electrodes) and lack of most of the constituents of the in-vivo like environment: cell morphology, cell-to-cell interaction and neuritic outgrowth in all directions. Cells in a brain region develop in a 3D space and interact with a complex multi-cellular environment and extracellular matrix. Under this perspective, 3D networks coupled to micro-transducer arrays, represent a new and powerful in-vitro model capable of better emulating in-vivo physiology. In this work, we present a new experimental paradigm constituted by 3D hippocampal networks coupled to Micro-Electrode-Arrays (MEAs) and we show how the features of the recorded network dynamics differ from the corresponding 2D network model. Further development of the proposed 3D in-vitro model by adding embedded functionalized scaffolds might open new prospects for manipulating, stimulating and recording the neuronal activity to elucidate neurophysiological mechanisms and to design bio-hybrid microsystems.

Network dynamics of 3D engineered neuronal cultures: a new experimental model for in-vitro electrophysiology

PubMed Central

Frega, Monica; Tedesco, Mariateresa; Massobrio, Paolo; Pesce, Mattia; Martinoia, Sergio

2014-01-01

Despite the extensive use of in-vitro models for neuroscientific investigations and notwithstanding the growing field of network electrophysiology, all studies on cultured cells devoted to elucidate neurophysiological mechanisms and computational properties, are based on 2D neuronal networks. These networks are usually grown onto specific rigid substrates (also with embedded electrodes) and lack of most of the constituents of the in-vivo like environment: cell morphology, cell-to-cell interaction and neuritic outgrowth in all directions. Cells in a brain region develop in a 3D space and interact with a complex multi-cellular environment and extracellular matrix. Under this perspective, 3D networks coupled to micro-transducer arrays, represent a new and powerful in-vitro model capable of better emulating in-vivo physiology. In this work, we present a new experimental paradigm constituted by 3D hippocampal networks coupled to Micro-Electrode-Arrays (MEAs) and we show how the features of the recorded network dynamics differ from the corresponding 2D network model. Further development of the proposed 3D in-vitro model by adding embedded functionalized scaffolds might open new prospects for manipulating, stimulating and recording the neuronal activity to elucidate neurophysiological mechanisms and to design bio-hybrid microsystems. PMID:24976386

Recent progress concerning the production of controlled highly oriented electrospun nanofibrous arrays

NASA Astrophysics Data System (ADS)

Manea, L. R.; Hristian, L.; Leon, A. L.; Popa, A.

2016-08-01

Among the foreground domains of all the research-development programs at national and international level, a special place is occupied by that concerning the nanosciences, nanotechnologies, new materials and technologies. Electrospinning found a well-deserved place in this space, offering the preparation of nanomaterials with distinctive properties and applications in medicine, environment, photonic sensors, filters, etc. These multiple applications are generated by the fact that the electrospinning technology makes available the production of nanofibers with controllable characteristics (length, porosity, density, and mechanical characteristics), complexity and architecture. The apparition of 3D printing technology favors the production of complex nanofibrous structures, controlled assembly, self-assembly of electrospun nanofibers for the production of scaffolds used in various medical applications. The architecture of fibrous deposits has a special influence on the subsequent development of the cells of the reconstructed organism. The present work proposes to study of recent progress concerning the production of controlled highly oriented electrospun nanofibrous arrays and progress in research on the production of complex 2D and 3D structures.

Immersive Visualization of the Solid Earth

NASA Astrophysics Data System (ADS)

Kreylos, O.; Kellogg, L. H.

2017-12-01

Immersive visualization using virtual reality (VR) display technology offers unique benefits for the visual analysis of complex three-dimensional data such as tomographic images of the mantle and higher-dimensional data such as computational geodynamics models of mantle convection or even planetary dynamos. Unlike "traditional" visualization, which has to project 3D scalar data or vectors onto a 2D screen for display, VR can display 3D data in a pseudo-holographic (head-tracked stereoscopic) form, and does therefore not suffer the distortions of relative positions, sizes, distances, and angles that are inherent in 2D projection and interfere with interpretation. As a result, researchers can apply their spatial reasoning skills to 3D data in the same way they can to real objects or environments, as well as to complex objects like vector fields. 3D Visualizer is an application to visualize 3D volumetric data, such as results from mantle convection simulations or seismic tomography reconstructions, using VR display technology and a strong focus on interactive exploration. Unlike other visualization software, 3D Visualizer does not present static visualizations, such as a set of cross-sections at pre-selected positions and orientations, but instead lets users ask questions of their data, for example by dragging a cross-section through the data's domain with their hands and seeing data mapped onto that cross-section in real time, or by touching a point inside the data domain, and immediately seeing an isosurface connecting all points having the same data value as the touched point. Combined with tools allowing 3D measurements of positions, distances, and angles, and with annotation tools that allow free-hand sketching directly in 3D data space, the outcome of using 3D Visualizer is not primarily a set of pictures, but derived data to be used for subsequent analysis. 3D Visualizer works best in virtual reality, either in high-end facility-scale environments such as CAVEs, or using commodity low-cost virtual reality headsets such as HTC's Vive. The recent emergence of high-quality commodity VR means that researchers can buy a complete VR system off the shelf, install it and the 3D Visualizer software themselves, and start using it for data analysis immediately.

Laser alchemy: direct writing of multifunctional components in a glass chip with femtosecond laser pulses

NASA Astrophysics Data System (ADS)

Liao, Yang; Lin, Jintian; Cheng, Ya

2013-12-01

Recently, hybrid integration of multifunctional micro-components for creating complex, intelligent micro/nano systems has attracted significant attention. These micro-/nano-systems have important applications in a variety of areas, such as healthcare, environment, communication, national security, and so on. However, fabrication of micro/nano systems incorporated with different functions is still a challenging task, which generally requires fabrication of discrete microcomponents beforehand followed by assembly and packaging procedures. Furthermore, current micro-/nano-fabrication techniques are mainly based on the well-established planar lithographic approach, which suffer from severe issues in producing three dimensional (3D) structures with complex geometries and arbitrary configurations. In recent years, the rapid development of femtosecond laser machining technology has enabled 3D direct fabrication and integration of multifunctional components, such as microfluidics, microoptics, micromechanics, microelectronics, etc., into single substrates. In this invited talk, we present our recent progress in this active area. Particularly, we focus on fabrication of 3D micro- and nanofluidic devices and 3D high-Q microcavities in glass substrates by femtosecond laser direct writing.

Evaluation of the cognitive effects of travel technique in complex real and virtual environments.

PubMed

Suma, Evan A; Finkelstein, Samantha L; Reid, Myra; V Babu, Sabarish; Ulinski, Amy C; Hodges, Larry F

2010-01-01

We report a series of experiments conducted to investigate the effects of travel technique on information gathering and cognition in complex virtual environments. In the first experiment, participants completed a non-branching multilevel 3D maze at their own pace using either real walking or one of two virtual travel techniques. In the second experiment, we constructed a real-world maze with branching pathways and modeled an identical virtual environment. Participants explored either the real or virtual maze for a predetermined amount of time using real walking or a virtual travel technique. Our results across experiments suggest that for complex environments requiring a large number of turns, virtual travel is an acceptable substitute for real walking if the goal of the application involves learning or reasoning based on information presented in the virtual world. However, for applications that require fast, efficient navigation or travel that closely resembles real-world behavior, real walking has advantages over common joystick-based virtual travel techniques.

Analysis and Description of HOLTIN Service Provision for AECG monitoring in Complex Indoor Environments

PubMed Central

Led, Santiago; Azpilicueta, Leire; Aguirre, Erik; de Espronceda, Miguel Martínez; Serrano, Luis; Falcone, Francisco

2013-01-01

In this work, a novel ambulatory ECG monitoring device developed in-house called HOLTIN is analyzed when operating in complex indoor scenarios. The HOLTIN system is described, from the technological platform level to its functional model. In addition, by using in-house 3D ray launching simulation code, the wireless channel behavior, which enables ubiquitous operation, is performed. The effect of human body presence is taken into account by a novel simplified model embedded within the 3D Ray Launching code. Simulation as well as measurement results are presented, showing good agreement. These results may aid in the adequate deployment of this novel device to automate conventional medical processes, increasing the coverage radius and optimizing energy consumption. PMID:23584122

Collaborative Multi-Scale 3d City and Infrastructure Modeling and Simulation

NASA Astrophysics Data System (ADS)

Breunig, M.; Borrmann, A.; Rank, E.; Hinz, S.; Kolbe, T.; Schilcher, M.; Mundani, R.-P.; Jubierre, J. R.; Flurl, M.; Thomsen, A.; Donaubauer, A.; Ji, Y.; Urban, S.; Laun, S.; Vilgertshofer, S.; Willenborg, B.; Menninghaus, M.; Steuer, H.; Wursthorn, S.; Leitloff, J.; Al-Doori, M.; Mazroobsemnani, N.

2017-09-01

Computer-aided collaborative and multi-scale 3D planning are challenges for complex railway and subway track infrastructure projects in the built environment. Many legal, economic, environmental, and structural requirements have to be taken into account. The stringent use of 3D models in the different phases of the planning process facilitates communication and collaboration between the stake holders such as civil engineers, geological engineers, and decision makers. This paper presents concepts, developments, and experiences gained by an interdisciplinary research group coming from civil engineering informatics and geo-informatics banding together skills of both, the Building Information Modeling and the 3D GIS world. New approaches including the development of a collaborative platform and 3D multi-scale modelling are proposed for collaborative planning and simulation to improve the digital 3D planning of subway tracks and other infrastructures. Experiences during this research and lessons learned are presented as well as an outlook on future research focusing on Building Information Modeling and 3D GIS applications for cities of the future.

Human lung fibroblast-derived matrix facilitates vascular morphogenesis in 3D environment and enhances skin wound healing.

PubMed

Du, Ping; Suhaeri, Muhammad; Ha, Sang Su; Oh, Seung Ja; Kim, Sang-Heon; Park, Kwideok

2017-05-01

Extracellular matrix (ECM) is crucial to many aspects of vascular morphogenesis and maintenance of vasculature function. Currently the recapitulation of angiogenic ECM microenvironment is still challenging, due mainly to its diverse components and complex organization. Here we investigate the angiogenic potential of human lung fibroblast-derived matrix (hFDM) in creating a three-dimensional (3D) vascular construct. hFDM was obtained via decellularization of in vitro cultured human lung fibroblasts and analyzed via immunofluorescence staining and ELISA, which detect multiple ECM macromolecules and angiogenic growth factors (GFs). Human umbilical vein endothelial cells (HUVECs) morphology was more elongated and better proliferative on hFDM than on gelatin-coated substrate. To prepare 3D construct, hFDM is collected, quantitatively analyzed, and incorporated in collagen hydrogel (Col) with HUVECs. Capillary-like structure (CLS) formation at 7day was significantly better with the groups containing higher doses of hFDM compared to the Col group (control). Moreover, the group (Col/hFDM/GFs) with both hFDM and angiogenic GFs (VEGF, bFGF, SDF-1) showed the synergistic activity on CLS formation and found much larger capillary lumen diameters with time. Further analysis of hFDM via angiogenesis antibody array kit reveals abundant biochemical cues, such as angiogenesis-related cytokines, GFs, and proteolytic enzymes. Significantly up-regulated expression of VE-cadherin and ECM-specific integrin subunits was also noticed in Col/hFDM/GFs. In addition, transplantation of Col/hFMD/GFs with HUVECs in skin wound model presents more effective re-epithelialization, many regenerated hair follicles, better transplanted cells viability, and advanced neovascularization. We believe that current system is a very promising platform for 3D vasculature construction in vitro and for cell delivery toward therapeutic applications in vivo. Functional 3D vasculature construction in vitro is still challenging due to the difficulty of recapitulating the complex angiogenic extracellular matrix (ECM) environment. Herein, we present a simple and practical method to create an angiogenic 3D environment via incorporation of human lung fibroblast-derived matrix (hFDM) into collagen hydrogel. We found that hFDM offers a significantly improved angiogenic microenvironment for HUVECs on 2D substrates and in 3D construct. A synergistic effect of hFDM and angiogenic growth factors has been well confirmed in 3D condition. The prevascularized 3D collagen constructs also facilitate skin wound healing. We believe that current system should be a convenient and powerful platform in engineering 3D vasculature in vitro, and in delivering cells for therapeutic purposes in vivo. Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Current State-of-the-Art 3D Tissue Models and Their Compatibility with Live Cell Imaging.

PubMed

Bardsley, Katie; Deegan, Anthony J; El Haj, Alicia; Yang, Ying

2017-01-01

Mammalian cells grow within a complex three-dimensional (3D) microenvironment where multiple cells are organized and surrounded by extracellular matrix (ECM). The quantity and types of ECM components, alongside cell-to-cell and cell-to-matrix interactions dictate cellular differentiation, proliferation and function in vivo. To mimic natural cellular activities, various 3D tissue culture models have been established to replace conventional two dimensional (2D) culture environments. Allowing for both characterization and visualization of cellular activities within possibly bulky 3D tissue models presents considerable challenges due to the increased thickness and subsequent light scattering features of such 3D models. In this chapter, state-of-the-art methodologies used to establish 3D tissue models are discussed, first with a focus on both scaffold-free and scaffold-based 3D tissue model formation. Following on, multiple 3D live cell imaging systems, mainly optical imaging modalities, are introduced. Their advantages and disadvantages are discussed, with the aim of stimulating more research in this highly demanding research area.

Vinculin is required for cell polarization, migration, and extracellular matrix remodeling in 3D collagen

PubMed Central

Thievessen, Ingo; Fakhri, Nikta; Steinwachs, Julian; Kraus, Viola; McIsaac, R. Scott; Gao, Liang; Chen, Bi-Chang; Baird, Michelle A.; Davidson, Michael W.; Betzig, Eric; Oldenbourg, Rudolf; Waterman, Clare M.; Fabry, Ben

2015-01-01

Vinculin is filamentous (F)-actin-binding protein enriched in integrin-based adhesions to the extracellular matrix (ECM). Whereas studies in 2-dimensional (2D) tissue culture models have suggested that vinculin negatively regulates cell migration by promoting cytoskeleton–ECM coupling to strengthen and stabilize adhesions, its role in regulating cell migration in more physiologic, 3-dimensional (3D) environments is unclear. To address the role of vinculin in 3D cell migration, we analyzed the morphodynamics, migration, and ECM remodeling of primary murine embryonic fibroblasts (MEFs) with cre/loxP-mediated vinculin gene disruption in 3D collagen I cultures. We found that vinculin promoted 3D cell migration by increasing directional persistence. Vinculin was necessary for persistent cell protrusion, cell elongation, and stable cell orientation in 3D collagen, but was dispensable for lamellipodia formation, suggesting that vinculin-mediated cell adhesion to the ECM is needed to convert actin-based cell protrusion into persistent cell shape change and migration. Consistent with this finding, vinculin was necessary for efficient traction force generation in 3D collagen without affecting myosin II activity and promoted 3D collagen fiber alignment and macroscopical gel contraction. Our results suggest that vinculin promotes directionally persistent cell migration and tension-dependent ECM remodeling in complex 3D environments by increasing cell–ECM adhesion and traction force generation.—Thievessen, I., Fakhri, N., Steinwachs, J., Kraus, V., McIsaac, R. S., Gao, L., Chen, B.-C., Baird, M. A., Davidson, M. W., Betzig, E., Oldenbourg, R., Waterman, C., M., Fabry, B. Vinculin is required for cell polarization, migration, and extracellular matrix remodeling in 3D collagen. PMID:26195589

Luminescence of europium (III) complexes for visualization

NASA Astrophysics Data System (ADS)

Kolontaeva, Olga A.; Pozharov, Mikhail V.; Korolovich, Vladimir F.; Khokhlova, Anastasia R.; Kirdyanova, Anna N.; Burmistrova, Natalia A.; Zakharova, Tamara V.; Goryacheva, Irina Y.

2016-04-01

With the purpose to develop bright non-toxic luminescent label for theranostic application we have studied complexation of lanthanide dipicolinates (2,6-pyridinedicarboxylates) by sodium alginate and effect of thermal exposure of synthesized micro-capsules on their luminescent properties. Synthesized micro-capsules are stable in acidic medium but dissolve at pH ~ 4 due to transformation of cationic europium dipicolinate complex to anionic. Luminescence studies have shown that emission spectra of europium(III)-alginate complexes (both chloride and dipicolinate) contain two intensive bands characteristic to Eu3+ ion (5D0 --> 7F1 (590 nm) and 5D0 --> 7F1 (612 nm)). We have also found that at 160ºC europium(III)- alginate micro-capsules decompose to black, soot-like substance, therefore, their thermal treatment must be performed in closed environment (i.e., sealed ampoules).

Three-Dimensional Rotating Wall Vessel-Derived Cell Culture Models for Studying Virus-Host Interactions

PubMed Central

Gardner, Jameson K.; Herbst-Kralovetz, Melissa M.

2016-01-01

The key to better understanding complex virus-host interactions is the utilization of robust three-dimensional (3D) human cell cultures that effectively recapitulate native tissue architecture and model the microenvironment. A lack of physiologically-relevant animal models for many viruses has limited the elucidation of factors that influence viral pathogenesis and of complex host immune mechanisms. Conventional monolayer cell cultures may support viral infection, but are unable to form the tissue structures and complex microenvironments that mimic host physiology and, therefore, limiting their translational utility. The rotating wall vessel (RWV) bioreactor was designed by the National Aeronautics and Space Administration (NASA) to model microgravity and was later found to more accurately reproduce features of human tissue in vivo. Cells grown in RWV bioreactors develop in a low fluid-shear environment, which enables cells to form complex 3D tissue-like aggregates. A wide variety of human tissues (from neuronal to vaginal tissue) have been grown in RWV bioreactors and have been shown to support productive viral infection and physiological meaningful host responses. The in vivo-like characteristics and cellular features of the human 3D RWV-derived aggregates make them ideal model systems to effectively recapitulate pathophysiology and host responses necessary to conduct rigorous basic science, preclinical and translational studies. PMID:27834891

3D printing of soft robotic systems

NASA Astrophysics Data System (ADS)

Wallin, T. J.; Pikul, J.; Shepherd, R. F.

2018-06-01

Soft robots are capable of mimicking the complex motion of animals. Soft robotic systems are defined by their compliance, which allows for continuous and often responsive localized deformation. These features make soft robots especially interesting for integration with human tissues, for example, the implementation of biomedical devices, and for robotic performance in harsh or uncertain environments, for example, exploration in confined spaces or locomotion on uneven terrain. Advances in soft materials and additive manufacturing technologies have enabled the design of soft robots with sophisticated capabilities, such as jumping, complex 3D movements, gripping and releasing. In this Review, we examine the essential soft material properties for different elements of soft robots, highlighting the most relevant polymer systems. Advantages and limitations of different additive manufacturing processes, including 3D printing, fused deposition modelling, direct ink writing, selective laser sintering, inkjet printing and stereolithography, are discussed, and the different techniques are investigated for their application in soft robotic fabrication. Finally, we explore integrated robotic systems and give an outlook for the future of the field and remaining challenges.

Thermal and mechanical properties of selected 3D printed thermoplastics in the cryogenic temperature regime

NASA Astrophysics Data System (ADS)

Weiss, K.-P.; Bagrets, N.; Lange, C.; Goldacker, W.; Wohlgemuth, J.

2015-12-01

Insulating materials for use in cryogenic boundary conditions are still limited to a proved selection as Polyamid, Glasfiber reinforced resins, PEEK, Vespel etc. These materials are usually formed to parts by mechanical machining or sometimes by cast methods. Shaping complex geometries in one piece is limited. Innovative 3D printing is now an upcoming revolutionary technology to construct functional parts from a couple of thermoplastic materials as ABS, Nylon and others which possess quite good mechanical stability and allow realizing very complex shapes with very subtle details. Even a wide range of material mixtures is an option and thermal treatments can be used to finish the material structure for higher performance. The use of such materials in cryogenic environment is very attractive but so far poor experience exists. In this paper, first investigations of the thermal conductivity, expansion and mechanical strength are presented for a few selected commercial 3D material samples to evaluate their application prospects in the cryogenic temperature regime.

Vinculin contributes to Cell Invasion by Regulating Contractile Activation

NASA Astrophysics Data System (ADS)

Mierke, Claudia Tanja

2008-07-01

Vinculin is a component of the focal adhesion complex and is described as a mechano-coupling protein connecting the integrin receptor and the actin cytoskeleton. Vinculin knock-out (k.o.) cells (vin-/-) displayed increased migration on a 2-D collagen- or fibronectin-coated substrate compared to wildtype cells, but the role of vinculin in cell migration through a 3-D connective tissue is unknown. We determined the invasiveness of established tumor cell lines using a 3-D collagen invasion assay. Gene expression analysis of 4 invasive and 4 non-invasive tumor cell lines revealed that vinculin expression was significantly increased in invasive tumor cell lines. To analyze the mechanisms by which vinculin increased cell invasion in a 3-D gel, we studied mouse embryonic fibroblasts wildtype and vin-/- cells. Wildtype cells were 3-fold more invasive compared vin-/- cells. We hypothesized that the ability to generate sufficient traction forces is a prerequisite for tumor cell migration in a 3-D connective tissue matrix. Using traction microscopy, we found that wildtype exerted 3-fold higher tractions on fibronectin-coated polyacrylamide gels compared to vin-/- cells. These results show that vinculin controls two fundamental functions that lead to opposite effects on cell migration in a 2-D vs. a 3-D environment: On the one hand, vinculin stabilizes the focal adhesions (mechano-coupling function) and thereby reduces motility in 2-D. On the other hand, vinculin is also a potent activator of traction generation (mechano-regulating function) that is important for cell invasion in a 3-D environment.

Investigating the Use of 3d Geovisualizations for Urban Design in Informal Settlement Upgrading in South Africa

NASA Astrophysics Data System (ADS)

Rautenbach, V.; Coetzee, S.; Çöltekin, A.

2016-06-01

Informal settlements are a common occurrence in South Africa, and to improve in-situ circumstances of communities living in informal settlements, upgrades and urban design processes are necessary. Spatial data and maps are essential throughout these processes to understand the current environment, plan new developments, and communicate the planned developments. All stakeholders need to understand maps to actively participate in the process. However, previous research demonstrated that map literacy was relatively low for many planning professionals in South Africa, which might hinder effective planning. Because 3D visualizations resemble the real environment more than traditional maps, many researchers posited that they would be easier to interpret. Thus, our goal is to investigate the effectiveness of 3D geovisualizations for urban design in informal settlement upgrading in South Africa. We consider all involved processes: 3D modelling, visualization design, and cognitive processes during map reading. We found that procedural modelling is a feasible alternative to time-consuming manual modelling, and can produce high quality models. When investigating the visualization design, the visual characteristics of 3D models and relevance of a subset of visual variables for urban design activities of informal settlement upgrades were qualitatively assessed. The results of three qualitative user experiments contributed to understanding the impact of various levels of complexity in 3D city models and map literacy of future geoinformatics and planning professionals when using 2D maps and 3D models. The research results can assist planners in designing suitable 3D models that can be used throughout all phases of the process.

a Comparison Between Active and Passive Techniques for Underwater 3d Applications

NASA Astrophysics Data System (ADS)

Bianco, G.; Gallo, A.; Bruno, F.; Muzzupappa, M.

2011-09-01

In the field of 3D scanning, there is an increasing need for more accurate technologies to acquire 3D models of close range objects. Underwater exploration, for example, is very hard to perform due to the hostile conditions and the bad visibility of the environment. Some application fields, like underwater archaeology, require to recover tridimensional data of objects that cannot be moved from their site or touched in order to avoid possible damages. Photogrammetry is widely used for underwater 3D acquisition, because it requires just one or two digital still or video cameras to acquire a sequence of images taken from different viewpoints. Stereo systems composed by a pair of cameras are often employed on underwater robots (i.e. ROVs, Remotely Operated Vehicles) and used by scuba divers, in order to survey archaeological sites, reconstruct complex 3D structures in aquatic environment, estimate in situ the length of marine organisms, etc. The stereo 3D reconstruction is based on the triangulation of corresponding points on the two views. This requires to find in both images common points and to match them (correspondence problem), determining a plane that contains the 3D point on the object. Another 3D technique, frequently used in air acquisition, solves this point-matching problem by projecting structured lighting patterns to codify the acquired scene. The corresponding points are identified associating a binary code in both images. In this work we have tested and compared two whole-field 3D imaging techniques (active and passive) based on stereo vision, in underwater environment. A 3D system has been designed, composed by a digital projector and two still cameras mounted in waterproof housing, so that it can perform the various acquisitions without changing the configuration of optical devices. The tests were conducted in a water tank in different turbidity conditions, on objects with different surface properties. In order to simulate a typical seafloor, we used various concentrations of clay. The performances of the two techniques are described and discussed. In particular, the point clouds obtained are compared in terms of number of acquired 3D points and geometrical deviation.

Eye Tracking to Explore the Impacts of Photorealistic 3d Representations in Pedstrian Navigation Performance

NASA Astrophysics Data System (ADS)

Dong, Weihua; Liao, Hua

2016-06-01

Despite the now-ubiquitous two-dimensional (2D) maps, photorealistic three-dimensional (3D) representations of cities (e.g., Google Earth) have gained much attention by scientists and public users as another option. However, there is no consistent evidence on the influences of 3D photorealism on pedestrian navigation. Whether 3D photorealism can communicate cartographic information for navigation with higher effectiveness and efficiency and lower cognitive workload compared to the traditional symbolic 2D maps remains unknown. This study aims to explore whether the photorealistic 3D representation can facilitate processes of map reading and navigation in digital environments using a lab-based eye tracking approach. Here we show the differences of symbolic 2D maps versus photorealistic 3D representations depending on users' eye-movement and navigation behaviour data. We found that the participants using the 3D representation were less effective, less efficient and were required higher cognitive workload than using the 2D map for map reading. However, participants using the 3D representation performed more efficiently in self-localization and orientation at the complex decision points. The empirical results can be helpful to improve the usability of pedestrian navigation maps in future designs.

Human3.6M: Large Scale Datasets and Predictive Methods for 3D Human Sensing in Natural Environments.

PubMed

Ionescu, Catalin; Papava, Dragos; Olaru, Vlad; Sminchisescu, Cristian

2014-07-01

We introduce a new dataset, Human3.6M, of 3.6 Million accurate 3D Human poses, acquired by recording the performance of 5 female and 6 male subjects, under 4 different viewpoints, for training realistic human sensing systems and for evaluating the next generation of human pose estimation models and algorithms. Besides increasing the size of the datasets in the current state-of-the-art by several orders of magnitude, we also aim to complement such datasets with a diverse set of motions and poses encountered as part of typical human activities (taking photos, talking on the phone, posing, greeting, eating, etc.), with additional synchronized image, human motion capture, and time of flight (depth) data, and with accurate 3D body scans of all the subject actors involved. We also provide controlled mixed reality evaluation scenarios where 3D human models are animated using motion capture and inserted using correct 3D geometry, in complex real environments, viewed with moving cameras, and under occlusion. Finally, we provide a set of large-scale statistical models and detailed evaluation baselines for the dataset illustrating its diversity and the scope for improvement by future work in the research community. Our experiments show that our best large-scale model can leverage our full training set to obtain a 20% improvement in performance compared to a training set of the scale of the largest existing public dataset for this problem. Yet the potential for improvement by leveraging higher capacity, more complex models with our large dataset, is substantially vaster and should stimulate future research. The dataset together with code for the associated large-scale learning models, features, visualization tools, as well as the evaluation server, is available online at http://vision.imar.ro/human3.6m.

Cognitive Virtualization: Combining Cognitive Models and Virtual Environments

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tuan Q. Tran; David I. Gertman; Donald D. Dudenhoeffer

2007-08-01

3D manikins are often used in visualizations to model human activity in complex settings. Manikins assist in developing understanding of human actions, movements and routines in a variety of different environments representing new conceptual designs. One such environment is a nuclear power plant control room, here they have the potential to be used to simulate more precise ergonomic assessments of human work stations. Next generation control rooms will pose numerous challenges for system designers. The manikin modeling approach by itself, however, may be insufficient for dealing with the desired technical advancements and challenges of next generation automated systems. Uncertainty regardingmore » effective staffing levels; and the potential for negative human performance consequences in the presence of advanced automated systems (e.g., reduced vigilance, poor situation awareness, mistrust or blind faith in automation, higher information load and increased complexity) call for further research. Baseline assessment of novel control room equipment(s) and configurations needs to be conducted. These design uncertainties can be reduced through complementary analysis that merges ergonomic manikin models with models of higher cognitive functions, such as attention, memory, decision-making, and problem-solving. This paper will discuss recent advancements in merging a theoretical-driven cognitive modeling framework within a 3D visualization modeling tool to evaluate of next generation control room human factors and ergonomic assessment. Though this discussion primary focuses on control room design, the application for such a merger between 3D visualization and cognitive modeling can be extended to various areas of focus such as training and scenario planning.« less

Characterising Tidal Flow Within AN Energetic Tidal Environment

NASA Astrophysics Data System (ADS)

Neill, S. P.; Goward Brown, A.; Lewis, M. J.

2016-02-01

The Pentland Firth is a highly energetic and complex tidal strait separating the north of Scotland with the Orkney Islands and is a key location for tidal energy exploitation. Topographic features including islands and headlands, combined with bathymetric complexities within the Pentland Firth create turbulent hydrodynamic flows which are difficult to observe. Site selection in tidal energy environments historically focuses on tidal current magnitude. Without consideration for the more complex hydrodynamics of tidal energy environments tidal energy developers may miss the opportunity to tune their devices or create environment specific tidal energy converters in order to harness the greatest potential from site. Fully characterising these tidal energy environments ensures economic energy extraction. Understanding the interaction of energy extraction with the environment will reduce uncertainty in site selection and allow mitigation of any potential environmental concerns. We apply the 3D ROMS model to the Pentland Firth with the aim of resolving uncertainties within tidal energy resource assessment. Flow magnitudes and directions are examined with a focus on tidal phasing and asymmetry and application to sediment dynamics. Using the ROMS model, it is possible to determine the extent to which the tidal resource varies temporally and spatially with tidal energy extraction. Accurately modelling the tidal dynamics within this environment ensures that potential consequences of tidal energy extraction on the surrounding environment are better understood.

Complex virtual urban environment modeling from CityGML data and OGC web services: application to the SIMFOR project

NASA Astrophysics Data System (ADS)

Chambelland, Jean-Christophe; Gesquière, Gilles

2012-03-01

Due to the advances in computer graphics and network speed it is possible to navigate in 3D virtual world in real time. This technology proposed for example in computer games, has been adapted for training systems. In this context, a collaborative serious game for urban crisis management called SIMFOR is born in France. This project has been designed for intensive realistic training and consequently must allow the players to create new urban operational theatres. In this goal, importing, structuring, processing and exchanging 3D urban data remains an important underlying problem. This communication will focus on the design of the 3D Environment Editor (EE) and the related data processes needed to prepare the data flow to be exploitable by the runtime environment of SIMFOR. We will use solutions proposed by the Open Geospatial Consortium (OGC) to aggregate and share data. A presentation of the proposed architecture will be given. The overall design of the EE and some strategies for efficiently analyzing, displaying and exporting large amount of urban CityGML information will be presented. An example illustrating the potentiality of the EE and the reliability of the proposed data processing will be proposed.

Amazon forest structure generates diurnal and seasonal variability in light utilization

Treesearch

Douglas C. Morton; Jeremy Rubio; Bruce D. Cook; Jean-Philippe Gastellu-Etchegorry; Marcos Longo; Hyeungu Choi; Maria Hunter; Michael Keller

2016-01-01

The complex three-dimensional (3-D) structure of tropical forests generates a diversity of light environments for canopy and understory trees. Understanding diurnal and seasonal changes in light availability is critical for interpreting measurements of net ecosystem exchange and improving ecosystem models. Here, we used the Discrete Anisotropic Radiative Transfer (DART...

The orbital ground state of the azide-substrate complex of human heme oxygenase is an indicator of distal H-bonding: implications for the enzyme mechanism.

PubMed

Ogura, Hiroshi; Evans, John P; Peng, Dungeng; Satterlee, James D; Ortiz de Montellano, Paul R; La Mar, Gerd N

2009-04-14

The active site electronic structure of the azide complex of substrate-bound human heme oxygenase 1 (hHO) has been investigated by (1)H NMR spectroscopy to shed light on the orbital/spin ground state as an indicator of the unique distal pocket environment of the enzyme. Two-dimensional (1)H NMR assignments of the substrate and substrate-contact residue signals reveal a pattern of substrate methyl contact shifts that places the lone iron pi-spin in the d(xz) orbital, rather than the d(yz) orbital found in the cyanide complex. Comparison of iron spin relaxivity, magnetic anisotropy, and magnetic susceptibilities argues for a low-spin, (d(xy))(2)(d(yz),d(xz))(3), ground state in both azide and cyanide complexes. The switch from singly occupied d(yz) for the cyanide to d(xz) for the azide complex of hHO is shown to be consistent with the orbital hole determined by the azide pi-plane in the latter complex, which is approximately 90 degrees in-plane rotated from that of the imidazole pi-plane. The induction of the altered orbital ground state in the azide relative to the cyanide hHO complex, as well as the mean low-field bias of methyl hyperfine shifts and their paramagnetic relaxivity relative to those in globins, indicates that azide exerts a stronger ligand field in hHO than in the globins, or that the distal H-bonding to azide is weaker in hHO than in globins. The Asp140 --> Ala hHO mutant that abolishes activity retains the unusual WT azide complex spin/orbital ground state. The relevance of our findings for other HO complexes and the HO mechanism is discussed.

Application of 3D Laser Scanning Technology in Complex Rock Foundation Design

NASA Astrophysics Data System (ADS)

Junjie, Ma; Dan, Lu; Zhilong, Liu

2017-12-01

Taking the complex landform of Tanxi Mountain Landscape Bridge as an example, the application of 3D laser scanning technology in the mapping of complex rock foundations is studied in this paper. A set of 3D laser scanning technologies are formed and several key engineering problems are solved. The first is 3D laser scanning technology of complex landforms. 3D laser scanning technology is used to obtain a complete 3D point cloud data model of the complex landform. The detailed and accurate results of the surveying and mapping decrease the measuring time and supplementary measuring times. The second is 3D collaborative modeling of the complex landform. A 3D model of the complex landform is established based on the 3D point cloud data model. The super-structural foundation model is introduced for 3D collaborative design. The optimal design plan is selected and the construction progress is accelerated. And the last is finite-element analysis technology of the complex landform foundation. A 3D model of the complex landform is introduced into ANSYS for building a finite element model to calculate anti-slide stability of the rock, and provides a basis for the landform foundation design and construction.

Water based fluidic radio frequency metamaterials

NASA Astrophysics Data System (ADS)

Cai, Xiaobing; Zhao, Shaolin; Hu, Mingjun; Xiao, Junfeng; Zhang, Naibo; Yang, Jun

2017-11-01

Electromagnetic metamaterials offer great flexibility for wave manipulation and enable exceptional functionality design, ranging from negative refraction, anomalous reflection, super-resolution imaging, transformation optics to cloaking, etc. However, demonstration of metamaterials with unprecedented functionalities is still challenging and costly due to the structural complexity or special material properties. Here, we demonstrate for the first time the versatile fluidic radio frequency metamaterials with negative refraction using a water-embedded and metal-coated 3D architecture. Effective medium analysis confirms that metallic frames create an evanescent environment while simultaneously water cylinders produce negative permeability under Mie resonance. The water-metal coupled 3D architectures and the accessory devices for measurement are fabricated by 3D printing with post electroless deposition. Our study also reveals the great potential of fluidic metamaterials and versatility of the 3D printing process in rapid prototyping of customized metamaterials.

Abrasion-Resistant Aluminized-Coated Aramid Fabrics for Manufacture of Firefighters’ Protective Clothing

DTIC Science & Technology

1985-05-01

OK 3-600 IV -5 D. ELECTRON-BEAM (EB) CURABLE "OATINGS These coatings are formed by curing or crosslinking a complex mixture of multifunctional acrylic ...1. 8p. Cooper, B.E., D.W. Butler, inventors; Dow Coming Corp., assignee. Curable siloxane resin coating composition. EP patent 048,114. (1982) March...limit use in the water-prone firefighters environment. We believe other high-temperature melting resins , such as polysulfone or polyether-imide, would

Computational path planner for product assembly in complex environments

NASA Astrophysics Data System (ADS)

Shang, Wei; Liu, Jianhua; Ning, Ruxin; Liu, Mi

2013-03-01

Assembly path planning is a crucial problem in assembly related design and manufacturing processes. Sampling based motion planning algorithms are used for computational assembly path planning. However, the performance of such algorithms may degrade much in environments with complex product structure, narrow passages or other challenging scenarios. A computational path planner for automatic assembly path planning in complex 3D environments is presented. The global planning process is divided into three phases based on the environment and specific algorithms are proposed and utilized in each phase to solve the challenging issues. A novel ray test based stochastic collision detection method is proposed to evaluate the intersection between two polyhedral objects. This method avoids fake collisions in conventional methods and degrades the geometric constraint when a part has to be removed with surface contact with other parts. A refined history based rapidly-exploring random tree (RRT) algorithm which bias the growth of the tree based on its planning history is proposed and employed in the planning phase where the path is simple but the space is highly constrained. A novel adaptive RRT algorithm is developed for the path planning problem with challenging scenarios and uncertain environment. With extending values assigned on each tree node and extending schemes applied, the tree can adapts its growth to explore complex environments more efficiently. Experiments on the key algorithms are carried out and comparisons are made between the conventional path planning algorithms and the presented ones. The comparing results show that based on the proposed algorithms, the path planner can compute assembly path in challenging complex environments more efficiently and with higher success. This research provides the references to the study of computational assembly path planning under complex environments.

Tissue vascularization through 3D printing: Will technology bring us flow?

PubMed

Paulsen, S J; Miller, J S

2015-05-01

Though in vivo models provide the most physiologically relevant environment for studying tissue function, in vitro studies provide researchers with explicit control over experimental conditions and the potential to develop high throughput testing methods. In recent years, advancements in developmental biology research and imaging techniques have significantly improved our understanding of the processes involved in vascular development. However, the task of recreating the complex, multi-scale vasculature seen in in vivo systems remains elusive. 3D bioprinting offers a potential method to generate controlled vascular networks with hierarchical structure approaching that of in vivo networks. Bioprinting is an interdisciplinary field that relies on advances in 3D printing technology along with advances in imaging and computational modeling, which allow researchers to monitor cellular function and to better understand cellular environment within the printed tissue. As bioprinting technologies improve with regards to resolution, printing speed, available materials, and automation, 3D printing could be used to generate highly controlled vascularized tissues in a high throughput manner for use in regenerative medicine and the development of in vitro tissue models for research in developmental biology and vascular diseases. © 2015 Wiley Periodicals, Inc.

Multi-modal imaging, model-based tracking, and mixed reality visualisation for orthopaedic surgery

PubMed Central

Fuerst, Bernhard; Tateno, Keisuke; Johnson, Alex; Fotouhi, Javad; Osgood, Greg; Tombari, Federico; Navab, Nassir

2017-01-01

Orthopaedic surgeons are still following the decades old workflow of using dozens of two-dimensional fluoroscopic images to drill through complex 3D structures, e.g. pelvis. This Letter presents a mixed reality support system, which incorporates multi-modal data fusion and model-based surgical tool tracking for creating a mixed reality environment supporting screw placement in orthopaedic surgery. A red–green–blue–depth camera is rigidly attached to a mobile C-arm and is calibrated to the cone-beam computed tomography (CBCT) imaging space via iterative closest point algorithm. This allows real-time automatic fusion of reconstructed surface and/or 3D point clouds and synthetic fluoroscopic images obtained through CBCT imaging. An adapted 3D model-based tracking algorithm with automatic tool segmentation allows for tracking of the surgical tools occluded by hand. This proposed interactive 3D mixed reality environment provides an intuitive understanding of the surgical site and supports surgeons in quickly localising the entry point and orienting the surgical tool during screw placement. The authors validate the augmentation by measuring target registration error and also evaluate the tracking accuracy in the presence of partial occlusion. PMID:29184659

A knowledge-based object recognition system for applications in the space station

NASA Technical Reports Server (NTRS)

Dhawan, Atam P.

1988-01-01

A knowledge-based three-dimensional (3D) object recognition system is being developed. The system uses primitive-based hierarchical relational and structural matching for the recognition of 3D objects in the two-dimensional (2D) image for interpretation of the 3D scene. At present, the pre-processing, low-level preliminary segmentation, rule-based segmentation, and the feature extraction are completed. The data structure of the primitive viewing knowledge-base (PVKB) is also completed. Algorithms and programs based on attribute-trees matching for decomposing the segmented data into valid primitives were developed. The frame-based structural and relational descriptions of some objects were created and stored in a knowledge-base. This knowledge-base of the frame-based descriptions were developed on the MICROVAX-AI microcomputer in LISP environment. The simulated 3D scene of simple non-overlapping objects as well as real camera data of images of 3D objects of low-complexity have been successfully interpreted.

My Corporis Fabrica: an ontology-based tool for reasoning and querying on complex anatomical models

PubMed Central

2014-01-01

Background Multiple models of anatomy have been developed independently and for different purposes. In particular, 3D graphical models are specially useful for visualizing the different organs composing the human body, while ontologies such as FMA (Foundational Model of Anatomy) are symbolic models that provide a unified formal description of anatomy. Despite its comprehensive content concerning the anatomical structures, the lack of formal descriptions of anatomical functions in FMA limits its usage in many applications. In addition, the absence of connection between 3D models and anatomical ontologies makes it difficult and time-consuming to set up and access to the anatomical content of complex 3D objects. Results First, we provide a new ontology of anatomy called My Corporis Fabrica (MyCF), which conforms to FMA but extends it by making explicit how anatomical structures are composed, how they contribute to functions, and also how they can be related to 3D complex objects. Second, we have equipped MyCF with automatic reasoning capabilities that enable model checking and complex queries answering. We illustrate the added-value of such a declarative approach for interactive simulation and visualization as well as for teaching applications. Conclusions The novel vision of ontologies that we have developed in this paper enables a declarative assembly of different models to obtain composed models guaranteed to be anatomically valid while capturing the complexity of human anatomy. The main interest of this approach is its declarativity that makes possible for domain experts to enrich the knowledge base at any moment through simple editors without having to change the algorithmic machinery. This provides MyCF software environment a flexibility to process and add semantics on purpose for various applications that incorporate not only symbolic information but also 3D geometric models representing anatomical entities as well as other symbolic information like the anatomical functions. PMID:24936286

Synthesis and spectroscopic behavior of highly luminescent Eu 3+-dibenzoylmethanate (DBM) complexes with sulfoxide ligands

NASA Astrophysics Data System (ADS)

Niyama, E.; Brito, H. F.; Cremona, M.; Teotonio, E. E. S.; Reyes, R.; Brito, G. E. S.; Felinto, M. C. F. C.

2005-09-01

In this paper the synthesis, characterization and photoluminescent behavior of the [RE(DBM) 3L 2] complexes (RE = Gd and Eu) with a variety of sulfoxide ligands; L = benzyl sulfoxide (DBSO), methyl sulfoxide (DMSO), phenyl sulfoxide (DPSO) and p-tolyl sulfoxide (PTSO) have been investigated in solid state. The emission spectra of the Eu 3+-β-diketonate complexes show characteristics narrow bands arising from the 5D 0 → 7F J ( J = 0-4) transitions, which are split according to the selection rule for C n, C nv or C s site symmetries. The experimental Judd-Ofelt intensity parameters ( Ω2 and Ω4), radiative ( Arad) and non-radiative ( Anrad) decay rates, and R02 for the europium complexes have been determined and compared. The highest value of Ω2 (61.9 × 10 -20 cm 2) was obtained to the complex with PTSO ligand, indicating that Eu 3+ ion is in the highly polarizable chemical environment. The higher values of the experimental quantum yield ( q) and emission quantum efficiency of the emitter 5D 0 level ( η) for the Eu-complexes with DMSO, DBSO and PTSO sulfoxides suggest that these complexes are promising Light Conversion Molecular Devices (LCMDs). The lower value of quantum yield ( q = 1%), for the hydrated complex [Eu(DBM) 3(H 2O)], indicates that the luminescence quenching occurs via multiphonon relaxation by coupling with the OH-oscillators from water molecule coordinated to rare earth ion. The pure red emission of the Eu-complexes has been confirmed by ( x, y) color coordinates.

Complementarity of Historic Building Information Modelling and Geographic Information Systems

NASA Astrophysics Data System (ADS)

Yang, X.; Koehl, M.; Grussenmeyer, P.; Macher, H.

2016-06-01

In this paper, we discuss the potential of integrating both semantically rich models from Building Information Modelling (BIM) and Geographical Information Systems (GIS) to build the detailed 3D historic model. BIM contributes to the creation of a digital representation having all physical and functional building characteristics in several dimensions, as e.g. XYZ (3D), time and non-architectural information that are necessary for construction and management of buildings. GIS has potential in handling and managing spatial data especially exploring spatial relationships and is widely used in urban modelling. However, when considering heritage modelling, the specificity of irregular historical components makes it problematic to create the enriched model according to its complex architectural elements obtained from point clouds. Therefore, some open issues limiting the historic building 3D modelling will be discussed in this paper: how to deal with the complex elements composing historic buildings in BIM and GIS environment, how to build the enriched historic model, and why to construct different levels of details? By solving these problems, conceptualization, documentation and analysis of enriched Historic Building Information Modelling are developed and compared to traditional 3D models aimed primarily for visualization.

[Research progress on the technique and materials for three-dimensional bio-printing].

PubMed

Yang, Runhuai; Chen, Yueming; Ma, Changwang; Wang, Huiqin; Wang, Shuyue

2017-04-01

Three-dimensional (3D) bio-printing is a novel engineering technique by which the cells and support materials can be manufactured to a complex 3D structure. Compared with other 3D printing methods, 3D bio-printing should pay more attention to the biocompatible environment of the printing methods and the materials. Aimed at studying the feature of the 3D bio-printing, this paper mainly focuses on the current research state of 3D bio-printing, with the techniques and materials of the bio-printing especially emphasized. To introduce current printing methods, the inkjet method, extrusion method, stereolithography skill and laser-assisted technique are described. The printing precision, process, requirements and influence of all the techniques on cell status are compared. For introduction of the printing materials, the cross-link, biocompatibility and applications of common bio-printing materials are reviewed and compared. Most of the 3D bio-printing studies are being remained at the experimental stage up to now, so the review of 3D bio-printing could improve this technique for practical use, and it could also contribute to the further development of 3D bio-printing.

Towards next generation 3D cameras

NASA Astrophysics Data System (ADS)

Gupta, Mohit

2017-03-01

We are in the midst of a 3D revolution. Robots enabled by 3D cameras are beginning to autonomously drive cars, perform surgeries, and manage factories. However, when deployed in the real-world, these cameras face several challenges that prevent them from measuring 3D shape reliably. These challenges include large lighting variations (bright sunlight to dark night), presence of scattering media (fog, body tissue), and optically complex materials (metal, plastic). Due to these factors, 3D imaging is often the bottleneck in widespread adoption of several key robotics technologies. I will talk about our work on developing 3D cameras based on time-of-flight and active triangulation that addresses these long-standing problems. This includes designing `all-weather' cameras that can perform high-speed 3D scanning in harsh outdoor environments, as well as cameras that recover shape of objects with challenging material properties. These cameras are, for the first time, capable of measuring detailed (<100 microns resolution) scans in extremely demanding scenarios with low-cost components. Several of these cameras are making a practical impact in industrial automation, being adopted in robotic inspection and assembly systems.

Acetylcholine molecular arrays enable quantum information processing

NASA Astrophysics Data System (ADS)

Tamulis, Arvydas; Majauskaite, Kristina; Talaikis, Martynas; Zborowski, Krzysztof; Kairys, Visvaldas

2017-09-01

We have found self-assembly of four neurotransmitter acetylcholine (ACh) molecular complexes in a water molecules environment by using geometry optimization with DFT B97d method. These complexes organizes to regular arrays of ACh molecules possessing electronic spins, i.e. quantum information bits. These spin arrays could potentially be controlled by the application of a non-uniform external magnetic field. The proper sequence of resonant electromagnetic pulses would then drive all the spin groups into the 3-spin entangled state and proceed large scale quantum information bits.

Crystal structure of CD155 and electron microscopic studies of its complexes with polioviruses

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Ping; Mueller, Steffen; Morais, Marc C.

2010-11-02

When poliovirus (PV) recognizes its receptor, CD155, the virus changes from a 160S to a 135S particle before releasing its genome into the cytoplasm. CD155 is a transmembrane protein with 3 Ig-like extracellular domains, D1-D3, where D1 is recognized by the virus. The crystal structure of D1D2 has been determined to 3.5-{angstrom} resolution and fitted into {approx}8.5-{angstrom} resolution cryoelectron microscopy reconstructions of the virus-receptor complexes for the 3 PV serotypes. These structures show that, compared with human rhinoviruses, the virus-receptor interactions for PVs have a greater dependence on hydrophobic interactions, as might be required for a virus that can inhabitmore » environments of different pH. The pocket factor was shown to remain in the virus during the first recognition stage. The present structures, when combined with earlier mutational investigations, show that in the subsequent entry stage the receptor moves further into the canyon when at a physiological temperature, thereby expelling the pocket factor and separating the viral subunits to form 135S particles. These results provide a detailed analysis of how a nonenveloped virus can enter its host cell.« less

Chemotaxis of C. elegans in 3D media: a model for navigation of undulatory microswimmers

NASA Astrophysics Data System (ADS)

Patel, Amar; Bilbao, Alejandro; Rahman, Mizanur; Vanapalli, Siva; Blawzdziewicz, Jerzy

2017-11-01

While the natural environment of C. elegans consists of complex 3D media (e.g., decomposing organic matter and water), most studies of chemotactic behavior of this nematode are limited to 2D. We present a 3D chemotaxis model that combines a realistic geometrical representation of body movements associated with 3D maneuvers, an analysis of mechanical interactions of the nematode body with the surrounding medium to determine nematode trajectories, and a simple memory-function description of chemosensory apparatus that controls the frequency, magnitude, and timing of turning maneuvers. We show that two main chemotaxis strategies of C. elegans moving in 2D, i.e., the biased random walk and gradual turn, are effective also in 3D, provided that 2D turns are supplemented by the roll maneuvers that enable 3D reorientation. Optimal choices of chemosensing and gait-control parameters are discussed; we show that the nematode can maintain efficient chemotaxis in burrowing and swimming by adjusting the undulation frequency alone, without changing the chemotactic component of the body control. Understanding how C. elegans efficiently navigates in 3D media may help in developing self-navigating artificial microswimmers. Supported by NSF Grant No. CBET 1603627.

G2H--graphics-to-haptic virtual environment development tool for PC's.

PubMed

Acosta, E; Temkin, B; Krummel, T M; Heinrichs, W L

2000-01-01

For surgical training and preparations, the existing surgical virtual environments have shown great improvement. However, these improvements are more in the visual aspect. The incorporation of haptics into virtual reality base surgical simulations would enhance the sense of realism greatly. To aid in the development of the haptic surgical virtual environment we have created a graphics to haptic, G2H, virtual environment developer tool. G2H transforms graphical virtual environments (created or imported) to haptic virtual environments without programming. The G2H capability has been demonstrated using the complex 3D pelvic model of Lucy 2.0, the Stanford Visible Female. The pelvis was made haptic using G2H without any further programming effort.

Assembly of 4-, 6- and 8-connected Cd(II) pseudo-polymorphic coordination polymers: Synthesis, solvent-dependent structural variation and properties

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Zhao-Hao; Xue, Li-Ping, E-mail: lpxue@163.com; Miao, Shao-Bin

2016-08-15

The reaction of Cd(NO{sub 3}){sub 2}·4H{sub 2}O, 2,5-thiophenedicarboxylic acid (H{sub 2}tdc) and 1,2-bis(imidazol-1′-yl)methane (bimm) by modulating solvent systems yielded three highly connected pseudo-polymorphic coordination polymers based on different dinuclear [Cd{sub 2}(CO{sub 2}){sub 2}] subunits bridged by carboxylate groups. Single crystal structural analyses reveal structural variation from 4-connected 2D sql layer, 6-connected 2-fold interpenetrated 3D pcu to 8-connected 3D bcu-type network in compounds 1–3. The structural dissimilarity in the structures dependent on the coordination environments of Cd(II) ions and linking modes of mixed ligand influenced by different solvent systems during the synthesis process. Moreover, thermogravimetric and photoluminescence behaviors of 1–3 weremore » also investigated for the first time, and all the complexes emit blue luminescence in the solid state. - Graphical abstract: Key Topic. Different solvent systems modulated three Cd(II) pseudo-polymorphic coordination polymers based on thiophene-2,5-dicarboxylate and 1,2-bis(imidazol-1′-yl)methane mixed ligands. Display Omitted - Highlights: • Three solvent-dependent Cd(II) pseudo-polymorphic coordination polymers have been synthesized. • Structural variation from 4-connected 2D layer, 6-connected 2-fold interpenetrated 3D net to 8-connected 3D net. • All complexes emit blue luminescence.« less

a Critical Review of Automated Photogrammetric Processing of Large Datasets

NASA Astrophysics Data System (ADS)

Remondino, F.; Nocerino, E.; Toschi, I.; Menna, F.

2017-08-01

The paper reports some comparisons between commercial software able to automatically process image datasets for 3D reconstruction purposes. The main aspects investigated in the work are the capability to correctly orient large sets of image of complex environments, the metric quality of the results, replicability and redundancy. Different datasets are employed, each one featuring a diverse number of images, GSDs at cm and mm resolutions, and ground truth information to perform statistical analyses of the 3D results. A summary of (photogrammetric) terms is also provided, in order to provide rigorous terms of reference for comparisons and critical analyses.

A system of three-dimensional complex variables

NASA Technical Reports Server (NTRS)

Martin, E. Dale

1986-01-01

Some results of a new theory of multidimensional complex variables are reported, including analytic functions of a three-dimensional (3-D) complex variable. Three-dimensional complex numbers are defined, including vector properties and rules of multiplication. The necessary conditions for a function of a 3-D variable to be analytic are given and shown to be analogous to the 2-D Cauchy-Riemann equations. A simple example also demonstrates the analogy between the newly defined 3-D complex velocity and 3-D complex potential and the corresponding ordinary complex velocity and complex potential in two dimensions.

GADEN: A 3D Gas Dispersion Simulator for Mobile Robot Olfaction in Realistic Environments.

PubMed

Monroy, Javier; Hernandez-Bennets, Victor; Fan, Han; Lilienthal, Achim; Gonzalez-Jimenez, Javier

2017-06-23

This work presents a simulation framework developed under the widely used Robot Operating System (ROS) to enable the validation of robotics systems and gas sensing algorithms under realistic environments. The framework is rooted in the principles of computational fluid dynamics and filament dispersion theory, modeling wind flow and gas dispersion in 3D real-world scenarios (i.e., accounting for walls, furniture, etc.). Moreover, it integrates the simulation of different environmental sensors, such as metal oxide gas sensors, photo ionization detectors, or anemometers. We illustrate the potential and applicability of the proposed tool by presenting a simulation case in a complex and realistic office-like environment where gas leaks of different chemicals occur simultaneously. Furthermore, we accomplish quantitative and qualitative validation by comparing our simulated results against real-world data recorded inside a wind tunnel where methane was released under different wind flow profiles. Based on these results, we conclude that our simulation framework can provide a good approximation to real world measurements when advective airflows are present in the environment.

GADEN: A 3D Gas Dispersion Simulator for Mobile Robot Olfaction in Realistic Environments

PubMed Central

Hernandez-Bennetts, Victor; Fan, Han; Lilienthal, Achim; Gonzalez-Jimenez, Javier

2017-01-01

This work presents a simulation framework developed under the widely used Robot Operating System (ROS) to enable the validation of robotics systems and gas sensing algorithms under realistic environments. The framework is rooted in the principles of computational fluid dynamics and filament dispersion theory, modeling wind flow and gas dispersion in 3D real-world scenarios (i.e., accounting for walls, furniture, etc.). Moreover, it integrates the simulation of different environmental sensors, such as metal oxide gas sensors, photo ionization detectors, or anemometers. We illustrate the potential and applicability of the proposed tool by presenting a simulation case in a complex and realistic office-like environment where gas leaks of different chemicals occur simultaneously. Furthermore, we accomplish quantitative and qualitative validation by comparing our simulated results against real-world data recorded inside a wind tunnel where methane was released under different wind flow profiles. Based on these results, we conclude that our simulation framework can provide a good approximation to real world measurements when advective airflows are present in the environment. PMID:28644375

Probing Nuclear Spin Effects on Electronic Spin Coherence via EPR Measurements of Vanadium(IV) Complexes.

PubMed

Graham, Michael J; Krzyaniak, Matthew D; Wasielewski, Michael R; Freedman, Danna E

2017-07-17

Quantum information processing (QIP) has the potential to transform numerous fields from cryptography, to finance, to the simulation of quantum systems. A promising implementation of QIP employs unpaired electronic spins as qubits, the fundamental units of information. Though molecular electronic spins offer many advantages, including chemical tunability and facile addressability, the development of design principles for the synthesis of complexes that exhibit long qubit superposition lifetimes (also known as coherence times, or T 2 ) remains a challenge. As nuclear spins in the local qubit environment are a primary cause of shortened superposition lifetimes, we recently conducted a study which employed a modular spin-free ligand scaffold to place a spin-laden propyl moiety at a series of fixed distances from an S = 1 / 2 vanadium(IV) ion in a series of vanadyl complexes. We found that, within a radius of 4.0(4)-6.6(6) Å from the metal center, nuclei did not contribute to decoherence. To assess the generality of this important design principle and test its efficacy in a different coordination geometry, we synthesized and investigated three vanadium tris(dithiolene) complexes with the same ligand set employed in our previous study: K 2 [V(C 5 H 6 S 4 ) 3 ] (1), K 2 [V(C 7 H 6 S 6 ) 3 ] (2), and K 2 [V(C 9 H 6 S 8 ) 3 ] (3). We specifically interrogated solutions of these complexes in DMF-d 7 /toluene-d 8 with pulsed electron paramagnetic resonance spectroscopy and electron nuclear double resonance spectroscopy and found that the distance dependence present in the previously synthesized vanadyl complexes holds true in this series. We further examined the coherence properties of the series in a different solvent, MeCN-d 3 /toluene-d 8 , and found that an additional property, the charge density of the complex, also affects decoherence across the series. These results highlight a previously unknown design principle for augmenting T 2 and open new pathways for the rational synthesis of complexes with long coherence times.

The LINC complex contributes to heterochromatin organisation and transcriptional gene silencing in plants.

PubMed

Poulet, Axel; Duc, Céline; Voisin, Maxime; Desset, Sophie; Tutois, Sylvie; Vanrobays, Emmanuel; Benoit, Matthias; Evans, David E; Probst, Aline V; Tatout, Christophe

2017-02-01

The linker of nucleoskeleton and cytoskeleton (LINC) complex is an evolutionarily well-conserved protein bridge connecting the cytoplasmic and nuclear compartments across the nuclear membrane. While recent data support its function in nuclear morphology and meiosis, its involvement in chromatin organisation has not been studied in plants. Here, 3D imaging methods have been used to investigate nuclear morphology and chromatin organisation in interphase nuclei of the model plant Arabidopsis thaliana in which heterochromatin clusters in conspicuous chromatin domains called chromocentres. Chromocentres form a repressive chromatin environment contributing to transcriptional silencing of repeated sequences, a general mechanism needed for genome stability. Quantitative measurements of the 3D position of chromocentres indicate their close proximity to the nuclear periphery but that their position varies with nuclear volume and can be altered in specific mutants affecting the LINC complex. Finally, we propose that the plant LINC complex contributes to proper heterochromatin organisation and positioning at the nuclear periphery, since its alteration is associated with the release of transcriptional silencing as well as decompaction of heterochromatic sequences. © 2017. Published by The Company of Biologists Ltd.

A standardized set of 3-D objects for virtual reality research and applications.

PubMed

Peeters, David

2018-06-01

The use of immersive virtual reality as a research tool is rapidly increasing in numerous scientific disciplines. By combining ecological validity with strict experimental control, immersive virtual reality provides the potential to develop and test scientific theories in rich environments that closely resemble everyday settings. This article introduces the first standardized database of colored three-dimensional (3-D) objects that can be used in virtual reality and augmented reality research and applications. The 147 objects have been normed for name agreement, image agreement, familiarity, visual complexity, and corresponding lexical characteristics of the modal object names. The availability of standardized 3-D objects for virtual reality research is important, because reaching valid theoretical conclusions hinges critically on the use of well-controlled experimental stimuli. Sharing standardized 3-D objects across different virtual reality labs will allow for science to move forward more quickly.

Homology Modeling of Dopamine D2 and D3 Receptors: Molecular Dynamics Refinement and Docking Evaluation

PubMed Central

Platania, Chiara Bianca Maria; Salomone, Salvatore; Leggio, Gian Marco; Drago, Filippo; Bucolo, Claudio

2012-01-01

Dopamine (DA) receptors, a class of G-protein coupled receptors (GPCRs), have been targeted for drug development for the treatment of neurological, psychiatric and ocular disorders. The lack of structural information about GPCRs and their ligand complexes has prompted the development of homology models of these proteins aimed at structure-based drug design. Crystal structure of human dopamine D3 (hD3) receptor has been recently solved. Based on the hD3 receptor crystal structure we generated dopamine D2 and D3 receptor models and refined them with molecular dynamics (MD) protocol. Refined structures, obtained from the MD simulations in membrane environment, were subsequently used in molecular docking studies in order to investigate potential sites of interaction. The structure of hD3 and hD2L receptors was differentiated by means of MD simulations and D3 selective ligands were discriminated, in terms of binding energy, by docking calculation. Robust correlation of computed and experimental Ki was obtained for hD3 and hD2L receptor ligands. In conclusion, the present computational approach seems suitable to build and refine structure models of homologous dopamine receptors that may be of value for structure-based drug discovery of selective dopaminergic ligands. PMID:22970199

Three-dimensional printing: changing clinical care or just a passing fad?

PubMed

Ryan, Justin; Gregg, Chelsea; Frakes, David; Pophal, Stephen

2017-01-01

Advances in medical imaging and three-dimensional (3D) reconstruction software have enabled a proliferation of 3D modeling and 3D printing for clinical applications. In particular, 3D printing has garnered an extraordinary media presence over the past few years. There is growing optimism that 3D printing can address patient specificity and complexity for improved interventional and surgical planning. Will this relatively untested technology bring about a paradigm shift in the clinical environment, or is it just a transient fad? Case studies and series centered around 3D printing are omnipresent in clinical and engineering journals. These primarily qualitative studies support the potential efficacy of the emerging technology. Few studies analyze the value of 3D printing, weighing its potential benefits against increasing costs (e.g., institutional overhead, labor, and materials). Clinical integration of 3D printing is growing rapidly, and its adoption into clinical practice presents unique workflow challenges. There are numerous clinical trials on the horizon that will finally help to elucidate the measured impact of 3D printing on clinical outcomes through quantitative analyses of clinical and economic metrics. The contrived integration of 3D printing into clinical practice seems all but certain as the value of this technology becomes more and more evident.

Modular Extracellular Matrices: Solutions for the Puzzle

PubMed Central

Serban, Monica A.; Prestwich, Glenn D.

2008-01-01

The common technique of growing cells in two-dimensions (2-D) is gradually being replaced by culturing cells on matrices with more appropriate composition and stiffness, or by encapsulation of cells in three-dimensions (3-D). The universal acceptance of the new 3-D paradigm has been constrained by the absence of a commercially available, biocompatible material that offers ease of use, experimental flexibility, and a seamless transition from in vitro to in vivo applications. The challenge – the puzzle that needs a solution – is to replicate the complexity of the native extracellular matrix (ECM) environment with the minimum number of components necessary to allow cells to rebuild and replicate a given tissue. For use in drug discovery, toxicology, cell banking, and ultimately in reparative medicine, the ideal matrix would therefore need to be highly reproducible, manufacturable, approvable, and affordable. Herein we describe the development of a set of modular components that can be assembled into biomimetic materials that meet these requirements. These semi-synthetic ECMs, or sECMs, are based on hyaluronan derivatives that form covalently crosslinked, biodegradable hydrogels suitable for 3-D culture of primary and stem cells in vitro, and for tissue formation in vivo. The sECMs can be engineered to provide appropriate biological cues needed to recapitulate the complexity of a given ECM environment. Specific applications for different sECM compositions include stem cell expansion with control of differentiation, scar-free wound healing, growth factor delivery, cell delivery for osteochondral defect and liver repair, and development of vascularized tumor xenografts for personalized chemotherapy. PMID:18442709

Interactions of the "piano-stool" [ruthenium(II)(η(6) -arene)(quinolone)Cl](+) complexes with water; DFT computational study.

PubMed

Zábojníková, Tereza; Cajzl, Radim; Kljun, Jakob; Chval, Zdeněk; Turel, Iztok; Burda, Jaroslav V

2016-07-15

Full optimizations of stationary points along the reaction coordinate for the hydration of several quinolone Ru(II) half-sandwich complexes were performed in water environment using the B3PW91/6-31+G(d)/PCM/UAKS method. The role of diffuse functions (especially on oxygen) was found crucial for correct geometries along the reaction coordinate. Single-point (SP) calculations were performed at the B3LYP/6-311++G(2df,2pd)/DPCM/saled-UAKS level. In the first part, two possible reaction mechanisms-associative and dissociative were compared. It was found that the dissociative mechanism of the hydration process is kinetically slightly preferred. Another important conclusion concerns the reaction channels. It was found that substitution of chloride ligand (abbreviated in the text as dechlorination reaction) represents energetically and kinetically the most feasible pathway. In the second part the same hydration reaction was explored for reactivity comparison of the Ru(II)-complexes with several derivatives of nalidixic acid: cinoxacin, ofloxacin, and (thio)nalidixic acid. The hydration process is about four orders of magnitude faster in a basic solution compared to neutral/acidic environment with cinoxacin and nalidixic acid as the most reactive complexes in the former and latter environments, respectively. The explored hydration reaction is in all cases endergonic; nevertheless the endergonicity is substantially lower (by ∼6 kcal/mol) in basic environment. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

3-D inversion of complex magnetotelluric data from an Archean-Proterozoic terrain in northeastern São Francisco Craton, Brazil

NASA Astrophysics Data System (ADS)

Bologna, Mauricio S.; Egbert, Gary D.; Padilha, Antonio L.; Pádua, Marcelo B.; Vitorello, Ícaro

2017-09-01

We present a magnetotelluric (MT) study in the northeastern part of the São Francisco Craton that encompasses an Archean-Proterozoic terrain, the Serrinha Block, breached by a rift basin developed mostly in Early Cretaceous times during the opening of the South Atlantic Ocean. Even though the MT sites are regularly spaced, the profiles have different orientations from one another, making the data distribution over the area highly uneven and therefore non-ideal for 3-D modeling. However, the data set is very complex, with dimensionality analysis indicating prevalence of 3-D geoelectric structure. Results from 3-D inversion are evaluated for robustness and potentiality for yielding tectonic information. At upper crustal depths, the resulting 3-D model is coherent with surface geology, whereas at mid and lower crustal depths more cryptic structures are revealed, likely of Palaeoproterozoic age. The most striking features in the model are several strong (∼1 Ωṡm) crustal conductors beneath the central part of the Serrinha Block, which we attribute to a Palaeoproterozoic oceanic plate subduction and arc-continent collision event involving the Rio Itapicuru Greenstone Belt and the basement of the Serrinha Block. The west-dipping geometry of these conductors provides a constraint on subduction polarity and gives support to tectonic evolutionary models proposing that the Rio Itapicuru Belt was formed in an island arc environment.

A multiscale analysis of coral reef topographic complexity using lidar-derived bathymetry

USGS Publications Warehouse

Zawada, D.G.; Brock, J.C.

2009-01-01

Coral reefs represent one of the most irregular substrates in the marine environment. This roughness or topographic complexity is an important structural characteristic of reef habitats that affects a number of ecological and environmental attributes, including species diversity and water circulation. Little is known about the range of topographic complexity exhibited within a reef or between different reef systems. The objective of this study was to quantify topographic complexity for a 5-km x 5-km reefscape along the northern Florida Keys reef tract, over spatial scales ranging from meters to hundreds of meters. The underlying dataset was a 1-m spatial resolution, digital elevation model constructed from lidar measurements. Topographic complexity was quantified using a fractal algorithm, which provided a multi-scale characterization of reef roughness. The computed fractal dimensions (D) are a measure of substrate irregularity and are bounded between values of 2 and 3. Spatial patterns in D were positively correlated with known reef zonation in the area. Landward regions of the study site contain relatively smooth (D ??? 2.35) flat-topped patch reefs, which give way to rougher (D ??? 2.5), deep, knoll-shaped patch reefs. The seaward boundary contains a mixture of substrate features, including discontinuous shelf-edge reefs, and exhibits a corresponding range of roughness values (2.28 ??? D ??? 2.61). ?? 2009 Coastal Education and Research Foundation.

Evaluating the electronic structure of formal Ln II ions in Ln II(C 5H 4SiMe 3) 3 1– using XANES spectroscopy and DFT calculations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fieser, Megan E.; Ferrier, Maryline Ghislaine; Su, Jing

Here, the isolation of [K(2.2.2-cryptand)][Ln(C 5H 4SiMe 3) 3], formally containing LnII, for all lanthanides (excluding Pm) was surprising given that +2 oxidation states are typically regarded as inaccessible for most 4f-elements. Herein, X-ray absorption near-edge spectroscopy (XANES), ground-state density functional theory (DFT), and transition dipole moment calculations are used to investigate the possibility that Ln(C 5H 4SiMe 3) 3 1– (Ln = Pr, Nd, Sm, Gd, Tb, Dy, Y, Ho, Er, Tm, Yb and Lu) compounds represented molecular Ln II complexes. Results from the ground-state DFT calculations were supported by additional calculations that utilized complete-active-space multi-configuration approach with second-ordermore » perturbation theoretical correction (CASPT2). Through comparisons with standards, Ln(C 5H 4SiMe 3) 3 1– (Ln = Sm, Tm, Yb, Lu, Y) are determined to contain 4f 6 5d 0 (Sm II), 4f 13 5d 0 (Tm II), 4f 14 5d 0 (Yb II), 4f 14 5d 1 (Lu II), and 4d 1 (Y II) electronic configurations. Additionally, our results suggest that Ln(C 5H 4SiMe 3) 3 1– (Ln = Pr, Nd, Gd, Tb, Dy, Ho, and Er) also contain Ln II ions, but with 4f n 5d 1 configurations (not 4f n +1 5d 0). In these 4f n 5d 1 complexes, the C 3h-symmetric ligand environment provides a highly shielded 5d-orbital of a' symmetry that made the 4f n 5d 1 electronic configurations lower in energy than the more typical 4f n+1 5d 0 configuration.« less

Evaluating the electronic structure of formal Ln II ions in Ln II(C 5H 4SiMe 3) 3 1– using XANES spectroscopy and DFT calculations

DOE PAGES

Fieser, Megan E.; Ferrier, Maryline Ghislaine; Su, Jing; ...

2017-06-30

Here, the isolation of [K(2.2.2-cryptand)][Ln(C 5H 4SiMe 3) 3], formally containing LnII, for all lanthanides (excluding Pm) was surprising given that +2 oxidation states are typically regarded as inaccessible for most 4f-elements. Herein, X-ray absorption near-edge spectroscopy (XANES), ground-state density functional theory (DFT), and transition dipole moment calculations are used to investigate the possibility that Ln(C 5H 4SiMe 3) 3 1– (Ln = Pr, Nd, Sm, Gd, Tb, Dy, Y, Ho, Er, Tm, Yb and Lu) compounds represented molecular Ln II complexes. Results from the ground-state DFT calculations were supported by additional calculations that utilized complete-active-space multi-configuration approach with second-ordermore » perturbation theoretical correction (CASPT2). Through comparisons with standards, Ln(C 5H 4SiMe 3) 3 1– (Ln = Sm, Tm, Yb, Lu, Y) are determined to contain 4f 6 5d 0 (Sm II), 4f 13 5d 0 (Tm II), 4f 14 5d 0 (Yb II), 4f 14 5d 1 (Lu II), and 4d 1 (Y II) electronic configurations. Additionally, our results suggest that Ln(C 5H 4SiMe 3) 3 1– (Ln = Pr, Nd, Gd, Tb, Dy, Ho, and Er) also contain Ln II ions, but with 4f n 5d 1 configurations (not 4f n +1 5d 0). In these 4f n 5d 1 complexes, the C 3h-symmetric ligand environment provides a highly shielded 5d-orbital of a' symmetry that made the 4f n 5d 1 electronic configurations lower in energy than the more typical 4f n+1 5d 0 configuration.« less

SPICE Module for the Satellite Orbit Analysis Program (SOAP)

NASA Technical Reports Server (NTRS)

Coggi, John; Carnright, Robert; Hildebrand, Claude

2008-01-01

A SPICE module for the Satellite Orbit Analysis Program (SOAP) precisely represents complex motion and maneuvers in an interactive, 3D animated environment with support for user-defined quantitative outputs. (SPICE stands for Spacecraft, Planet, Instrument, Camera-matrix, and Events). This module enables the SOAP software to exploit NASA mission ephemeris represented in the JPL Ancillary Information Facility (NAIF) SPICE formats. Ephemeris types supported include position, velocity, and orientation for spacecraft and planetary bodies including the Sun, planets, natural satellites, comets, and asteroids. Entire missions can now be imported into SOAP for 3D visualization, playback, and analysis. The SOAP analysis and display features can now leverage detailed mission files to offer the analyst both a numerically correct and aesthetically pleasing combination of results that can be varied to study many hypothetical scenarios. The software provides a modeling and simulation environment that can encompass a broad variety of problems using orbital prediction. For example, ground coverage analysis, communications analysis, power and thermal analysis, and 3D visualization that provide the user with insight into complex geometric relations are included. The SOAP SPICE module allows distributed science and engineering teams to share common mission models of known pedigree, which greatly reduces duplication of effort and the potential for error. The use of the software spans all phases of the space system lifecycle, from the study of future concepts to operations and anomaly analysis. It allows SOAP software to correctly position and orient all of the principal bodies of the Solar System within a single simulation session along with multiple spacecraft trajectories and the orientation of mission payloads. In addition to the 3D visualization, the user can define numeric variables and x-y plots to quantitatively assess metrics of interest.

Paracousti-UQ: A Stochastic 3-D Acoustic Wave Propagation Algorithm.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Preston, Leiph

Acoustic full waveform algorithms, such as Paracousti, provide deterministic solutions in complex, 3-D variable environments. In reality, environmental and source characteristics are often only known in a statistical sense. Thus, to fully characterize the expected sound levels within an environment, this uncertainty in environmental and source factors should be incorporated into the acoustic simulations. Performing Monte Carlo (MC) simulations is one method of assessing this uncertainty, but it can quickly become computationally intractable for realistic problems. An alternative method, using the technique of stochastic partial differential equations (SPDE), allows computation of the statistical properties of output signals at a fractionmore » of the computational cost of MC. Paracousti-UQ solves the SPDE system of 3-D acoustic wave propagation equations and provides estimates of the uncertainty of the output simulated wave field (e.g., amplitudes, waveforms) based on estimated probability distributions of the input medium and source parameters. This report describes the derivation of the stochastic partial differential equations, their implementation, and comparison of Paracousti-UQ results with MC simulations using simple models.« less

The advantages of complementing MT profiles in 3-D environments with geomagnetic transfer function and interstation horizontal magnetic transfer function data: results from a synthetic case study

NASA Astrophysics Data System (ADS)

Campanyà, Joan; Ogaya, Xènia; Jones, Alan G.; Rath, Volker; Vozar, Jan; Meqbel, Naser

2016-12-01

As a consequence of measuring time variations of the electric and the magnetic field, which are related to current flow and charge distribution, magnetotelluric (MT) data in 2-D and 3-D environments are not only sensitive to the geoelectrical structures below the measuring points but also to any lateral anomalies surrounding the acquisition site. This behaviour complicates the characterization of the electrical resistivity distribution of the subsurface, particularly in complex areas. In this manuscript we assess the main advantages of complementing the standard MT impedance tensor (Z) data with interstation horizontal magnetic tensor (H) and geomagnetic transfer function (T) data in constraining the subsurface in a 3-D environment beneath a MT profile. Our analysis was performed using synthetic responses with added normally distributed and scattered random noise. The sensitivity of each type of data to different resistivity anomalies was evaluated, showing that the degree to which each site and each period is affected by the same anomaly depends on the type of data. A dimensionality analysis, using Z, H and T data, identified the presence of the 3-D anomalies close to the profile, suggesting a 3-D approach for recovering the electrical resistivity values of the subsurface. Finally, the capacity for recovering the geoelectrical structures of the subsurface was evaluated by performing joint inversion using different data combinations, quantifying the differences between the true synthetic model and the models from inversion process. Four main improvements were observed when performing joint inversion of Z, H and T data: (1) superior precision and accuracy at characterizing the electrical resistivity values of the anomalies below and outside the profile; (2) the potential to recover high electrical resistivity anomalies that are poorly recovered using Z data alone; (3) improvement in the characterization of the bottom and lateral boundaries of the anomalies with low electrical resistivity; and (4) superior imaging of the horizontal continuity of structures with low electrical resistivity. These advantages offer new opportunities for the MT method by making the results from a MT profile in a 3-D environment more convincing, supporting the possibility of high-resolution studies in 3-D areas without expending a large amount of economical and computational resources, and also offering better resolution of targets with high electrical resistivity.

New Insights Into the Mechanisms and Biological Roles of D-Amino Acids in Complex Eco-Systems

PubMed Central

Aliashkevich, Alena; Alvarez, Laura; Cava, Felipe

2018-01-01

In the environment bacteria share their habitat with a great diversity of organisms, from microbes to humans, animals and plants. In these complex communities, the production of extracellular effectors is a common strategy to control the biodiversity by interfering with the growth and/or viability of nearby microbes. One of such effectors relies on the production and release of extracellular D-amino acids which regulate diverse cellular processes such as cell wall biogenesis, biofilm integrity, and spore germination. Non-canonical D-amino acids are mainly produced by broad spectrum racemases (Bsr). Bsr’s promiscuity allows it to generate high concentrations of D-amino acids in environments with variable compositions of L-amino acids. However, it was not clear until recent whether these molecules exhibit divergent functions. Here we review the distinctive biological roles of D-amino acids, their mechanisms of action and their modulatory properties of the biodiversity of complex eco-systems. PMID:29681896

3D modeling of building indoor spaces and closed doors from imagery and point clouds.

PubMed

Díaz-Vilariño, Lucía; Khoshelham, Kourosh; Martínez-Sánchez, Joaquín; Arias, Pedro

2015-02-03

3D models of indoor environments are increasingly gaining importance due to the wide range of applications to which they can be subjected: from redesign and visualization to monitoring and simulation. These models usually exist only for newly constructed buildings; therefore, the development of automatic approaches for reconstructing 3D indoors from imagery and/or point clouds can make the process easier, faster and cheaper. Among the constructive elements defining a building interior, doors are very common elements and their detection can be very useful either for knowing the environment structure, to perform an efficient navigation or to plan appropriate evacuation routes. The fact that doors are topologically connected to walls by being coplanar, together with the unavoidable presence of clutter and occlusions indoors, increases the inherent complexity of the automation of the recognition process. In this work, we present a pipeline of techniques used for the reconstruction and interpretation of building interiors based on point clouds and images. The methodology analyses the visibility problem of indoor environments and goes in depth with door candidate detection. The presented approach is tested in real data sets showing its potential with a high door detection rate and applicability for robust and efficient envelope reconstruction.

Complexity of Products of Tungsten Corrosion: Comparison of the 3D Pourbaix Diagrams with the Experimental Data

NASA Astrophysics Data System (ADS)

Nave, Maryana I.; Kornev, Konstantin G.

2017-03-01

Tungsten is one of the most attractive metals in applications where materials are subject to high temperature and strong fields. However, in harsh aqueous environment, tungsten is prone to corrosion. Control of tungsten corrosion in aqueous solutions is a challenging task: as a transition metal, tungsten is able to produce a vast variety of oxides and hydrates. To reveal the thermodynamic pathway of corrosion at different conditions, the 3D Pourbaix diagrams relating the reduction potential, pH, and concentration of different tungsten-based compounds were constructed. These diagrams allow one to identify the most thermodynamically stable tungsten-based compounds. The 3D Pourbaix diagrams were used to explain different regimes of anodic dissolution of tungsten in aqueous solutions of potassium hydroxide.

i3Drive, a 3D interactive driving simulator.

PubMed

Ambroz, Miha; Prebil, Ivan

2010-01-01

i3Drive, a wheeled-vehicle simulator, can accurately simulate vehicles of various configurations with up to eight wheels in real time on a desktop PC. It presents the vehicle dynamics as an interactive animation in a virtual 3D environment. The application is fully GUI-controlled, giving users an easy overview of the simulation parameters and letting them adjust those parameters interactively. It models all relevant vehicle systems, including the mechanical models of the suspension, power train, and braking and steering systems. The simulation results generally correspond well with actual measurements, making the system useful for studying vehicle performance in various driving scenarios. i3Drive is thus a worthy complement to other, more complex tools for vehicle-dynamics simulation and analysis.

Definition of an intramolecular Eu-to-Eu energy transfer within a discrete [Eu2L] complex in solution.

PubMed

Nonat, Aline; Regueiro-Figueroa, Martín; Esteban-Gómez, David; de Blas, Andrés; Rodríguez-Blas, Teresa; Platas-Iglesias, Carlos; Charbonnière, Loïc J

2012-06-25

Ligand L, based on two do3a moieties linked by the methylene groups of 6,6'-dimethyl-2,2'-bipyridine, was synthesized and characterized. The addition of Ln salts to an aqueous solution of L (0.01 M Tris-HCl, pH 7.4) led to the successive formation of [LnL] and [Ln(2)L] complexes, as evidenced by UV/Vis and fluorescence titration experiments. Homodinuclear [Ln(2)L] complexes (Ln = Eu, Gd, Tb, Yb, and Lu) were prepared and characterized. The (1)H and (13)C NMR spectra of the Lu and Yb complexes in D(2)O solution (pD = 7.0) showed C(1) symmetry of these species in solution, pointing to two different chemical environments for the two lanthanide cations. The analysis of the chemical shifts of the Yb complex indicated that the two coordination sites present square antiprismatic (SAP) coordination environments around the metal ions. The spectroscopic properties of the [Tb(2)L] complex upon ligand excitation revealed conventional behavior with τ(H2O) = 2.05(1) ms and ϕ(H2O) = 51%, except for the calculation of the hydration number obtained from the luminescent lifetimes in H(2)O and D(2)O, which pointed to a non-integer value of 0.6 water molecules per Tb(III) ion. In contrast, the Eu complex revealed surprising features such as: 1) the presence of two and up to five components in the (5)D(0)→(7)F(0) and (5)D(0)→(7)F(1) emission bands, respectively; 2) marked differences between the normalized spectra obtained in H(2)O and D(2)O solutions; and 3) unconventional temporal evolution of the luminescence intensity at certain wavelengths, the intensity profile first displaying a rising step before the occurrence of the expected decay. Additional spectroscopic experiments performed on [Gd(2-x)Eu(x)L] complexes (x = 0.1 and 1.9) confirmed the presence of two distinct Eu sites with hydration numbers of 0 (site I) and 2 (site II), and showed that the unconventional temporal evolution of the emission intensity is the result of an unprecedented intramolecular Eu-to-Eu energy-transfer process. A mathematical model was developed to interpret the experimental data, leading to energy-transfer rates of 0.98 ms(-1) for the transfer from the site with q=0 to that with q=2 and vice versa. Hartree-Fock (HF) and density functional theory (DFT) calculations performed at the B3LYP level were used to investigate the conformation of the complex in solution, and to estimate the intermetallic distance, which provided Förster radii (R(0)) values of 8.1 Å for the energy transfer from site I to site II, and 6.8 Å for the reverse energy transfer. These results represent the first evidence of an intramolecular energy-transfer equilibrium between two identical lanthanide cations within a discrete molecular complex in solution. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Advanced 3-dimensional planning in neurosurgery.

PubMed

Ferroli, Paolo; Tringali, Giovanni; Acerbi, Francesco; Schiariti, Marco; Broggi, Morgan; Aquino, Domenico; Broggi, Giovanni

2013-01-01

During the past decades, medical applications of virtual reality technology have been developing rapidly, ranging from a research curiosity to a commercially and clinically important area of medical informatics and technology. With the aid of new technologies, the user is able to process large amounts of data sets to create accurate and almost realistic reconstructions of anatomic structures and related pathologies. As a result, a 3-diensional (3-D) representation is obtained, and surgeons can explore the brain for planning or training. Further improvement such as a feedback system increases the interaction between users and models by creating a virtual environment. Its use for advanced 3-D planning in neurosurgery is described. Different systems of medical image volume rendering have been used and analyzed for advanced 3-D planning: 1 is a commercial "ready-to-go" system (Dextroscope, Bracco, Volume Interaction, Singapore), whereas the others are open-source-based software (3-D Slicer, FSL, and FreesSurfer). Different neurosurgeons at our institution experienced how advanced 3-D planning before surgery allowed them to facilitate and increase their understanding of the complex anatomic and pathological relationships of the lesion. They all agreed that the preoperative experience of virtually planning the approach was helpful during the operative procedure. Virtual reality for advanced 3-D planning in neurosurgery has achieved considerable realism as a result of the available processing power of modern computers. Although it has been found useful to facilitate the understanding of complex anatomic relationships, further effort is needed to increase the quality of the interaction between the user and the model.

Neurite outgrowth at the interface of 2D and 3D growth environments

NASA Astrophysics Data System (ADS)

Kofron, Celinda M.; Fong, Vivian J.; Hoffman-Kim, Diane

2009-02-01

Growing neurons navigate complex environments, but in vitro systems for studying neuronal growth typically limit the cues to flat surfaces or a single type of cue, thereby limiting the resulting growth. Here we examined the growth of neurons presented with two-dimensional (2D) substrate-bound cues when these cues were presented in conjunction with a more complex three-dimensional (3D) architecture. Dorsal root ganglia (DRG) explants were cultured at the interface between a collagen I matrix and a glass coverslip. Laminin (LN) or chondroitin sulfate proteoglycans (CSPG) were uniformly coated on the surface of the glass coverslip or patterned in 50 µm tracks by microcontact printing. Quantitative analysis of neurite outgrowth with a novel grid system at multiple depths in the gel revealed several interesting trends. Most of the neurites extended at the surface of the gel when LN was presented whereas more neurites extended into the gel when CSPG was presented. Patterning of cues did not affect neurite density or depth of growth. However, neurite outgrowth near the surface of the gel aligned with LN patterns, and these extensions were significantly longer than neurites extended in other cultures. In interface cultures, DRG growth patterns varied with the type of cue where neurite density was higher in cultures presenting LN than in cultures presenting CSPG. These results represent an important step toward understanding how neurons integrate local structural and chemical cues to make net growth decisions.

Development of a Web Based Simulating System for Earthquake Modeling on the Grid

NASA Astrophysics Data System (ADS)

Seber, D.; Youn, C.; Kaiser, T.

2007-12-01

Existing cyberinfrastructure-based information, data and computational networks now allow development of state- of-the-art, user-friendly simulation environments that democratize access to high-end computational environments and provide new research opportunities for many research and educational communities. Within the Geosciences cyberinfrastructure network, GEON, we have developed the SYNSEIS (SYNthetic SEISmogram) toolkit to enable efficient computations of 2D and 3D seismic waveforms for a variety of research purposes especially for helping to analyze the EarthScope's USArray seismic data in a speedy and efficient environment. The underlying simulation software in SYNSEIS is a finite difference code, E3D, developed by LLNL (S. Larsen). The code is embedded within the SYNSEIS portlet environment and it is used by our toolkit to simulate seismic waveforms of earthquakes at regional distances (<1000km). Architecturally, SYNSEIS uses both Web Service and Grid computing resources in a portal-based work environment and has a built in access mechanism to connect to national supercomputer centers as well as to a dedicated, small-scale compute cluster for its runs. Even though Grid computing is well-established in many computing communities, its use among domain scientists still is not trivial because of multiple levels of complexities encountered. We grid-enabled E3D using our own dialect XML inputs that include geological models that are accessible through standard Web services within the GEON network. The XML inputs for this application contain structural geometries, source parameters, seismic velocity, density, attenuation values, number of time steps to compute, and number of stations. By enabling a portal based access to a such computational environment coupled with its dynamic user interface we enable a large user community to take advantage of such high end calculations in their research and educational activities. Our system can be used to promote an efficient and effective modeling environment to help scientists as well as educators in their daily activities and speed up the scientific discovery process.

Virtual Environmental Enrichment through Video Games Improves Hippocampal-Associated Memory

PubMed Central

Clemenson, Gregory D.

2015-01-01

The positive effects of environmental enrichment and their neural bases have been studied extensively in the rodent (van Praag et al., 2000). For example, simply modifying an animal's living environment to promote sensory stimulation can lead to (but is not limited to) enhancements in hippocampal cognition and neuroplasticity and can alleviate hippocampal cognitive deficits associated with neurodegenerative diseases and aging. We are interested in whether these manipulations that successfully enhance cognition (or mitigate cognitive decline) have similar influences on humans. Although there are many “enriching” aspects to daily life, we are constantly adapting to new experiences and situations within our own environment on a daily basis. Here, we hypothesize that the exploration of the vast and visually stimulating virtual environments within video games is a human correlate of environmental enrichment. We show that video gamers who specifically favor complex 3D video games performed better on a demanding recognition memory task that assesses participants' ability to discriminate highly similar lure items from repeated items. In addition, after 2 weeks of training on the 3D video game Super Mario 3D World, naive video gamers showed improved mnemonic discrimination ability and improvements on a virtual water maze task. Two control conditions (passive and training in a 2D game, Angry Birds), showed no such improvements. Furthermore, individual performance in both hippocampal-associated behaviors correlated with performance in Super Mario but not Angry Birds, suggesting that how individuals explored the virtual environment may influence hippocampal behavior. SIGNIFICANCE STATEMENT The hippocampus has long been associated with episodic memory and is commonly thought to rely on neuroplasticity to adapt to the ever-changing environment. In animals, it is well understood that exposing animals to a more stimulating environment, known as environmental enrichment, can stimulate neuroplasticity and improve hippocampal function and performance on hippocampally mediated memory tasks. Here, we suggest that the exploration of vast and visually stimulating environments within modern-day video games can act as a human correlate of environmental enrichment. Training naive video gamers in a rich 3D, but not 2D, video game, resulted in a significant improvement in hippocampus-associated cognition using several behavioral measures. Our results suggest that modern day video games may provide meaningful stimulation to the human hippocampus. PMID:26658864

Virtual Environmental Enrichment through Video Games Improves Hippocampal-Associated Memory.

PubMed

Clemenson, Gregory D; Stark, Craig E L

2015-12-09

The positive effects of environmental enrichment and their neural bases have been studied extensively in the rodent (van Praag et al., 2000). For example, simply modifying an animal's living environment to promote sensory stimulation can lead to (but is not limited to) enhancements in hippocampal cognition and neuroplasticity and can alleviate hippocampal cognitive deficits associated with neurodegenerative diseases and aging. We are interested in whether these manipulations that successfully enhance cognition (or mitigate cognitive decline) have similar influences on humans. Although there are many "enriching" aspects to daily life, we are constantly adapting to new experiences and situations within our own environment on a daily basis. Here, we hypothesize that the exploration of the vast and visually stimulating virtual environments within video games is a human correlate of environmental enrichment. We show that video gamers who specifically favor complex 3D video games performed better on a demanding recognition memory task that assesses participants' ability to discriminate highly similar lure items from repeated items. In addition, after 2 weeks of training on the 3D video game Super Mario 3D World, naive video gamers showed improved mnemonic discrimination ability and improvements on a virtual water maze task. Two control conditions (passive and training in a 2D game, Angry Birds), showed no such improvements. Furthermore, individual performance in both hippocampal-associated behaviors correlated with performance in Super Mario but not Angry Birds, suggesting that how individuals explored the virtual environment may influence hippocampal behavior. The hippocampus has long been associated with episodic memory and is commonly thought to rely on neuroplasticity to adapt to the ever-changing environment. In animals, it is well understood that exposing animals to a more stimulating environment, known as environmental enrichment, can stimulate neuroplasticity and improve hippocampal function and performance on hippocampally mediated memory tasks. Here, we suggest that the exploration of vast and visually stimulating environments within modern-day video games can act as a human correlate of environmental enrichment. Training naive video gamers in a rich 3D, but not 2D, video game, resulted in a significant improvement in hippocampus-associated cognition using several behavioral measures. Our results suggest that modern day video games may provide meaningful stimulation to the human hippocampus. Copyright © 2015 the authors 0270-6474/15/3516116-10$15.00/0.

The development of a virtual 3D model of the renal corpuscle from serial histological sections for E-learning environments.

PubMed

Roth, Jeremy A; Wilson, Timothy D; Sandig, Martin

2015-01-01

Histology is a core subject in the anatomical sciences where learners are challenged to interpret two-dimensional (2D) information (gained from histological sections) to extrapolate and understand the three-dimensional (3D) morphology of cells, tissues, and organs. In gross anatomical education 3D models and learning tools have been associated with improved learning outcomes, but similar tools have not been created for histology education to visualize complex cellular structure-function relationships. This study outlines steps in creating a virtual 3D model of the renal corpuscle from serial, semi-thin, histological sections obtained from epoxy resin-embedded kidney tissue. The virtual renal corpuscle model was generated by digital segmentation to identify: Bowman's capsule, nuclei of epithelial cells in the parietal capsule, afferent arteriole, efferent arteriole, proximal convoluted tubule, distal convoluted tubule, glomerular capillaries, podocyte nuclei, nuclei of extraglomerular mesangial cells, nuclei of epithelial cells of the macula densa in the distal convoluted tubule. In addition to the imported images of the original sections the software generates, and allows for visualization of, images of virtual sections generated in any desired orientation, thus serving as a "virtual microtome". These sections can be viewed separately or with the 3D model in transparency. This approach allows for the development of interactive e-learning tools designed to enhance histology education of microscopic structures with complex cellular interrelationships. Future studies will focus on testing the efficacy of interactive virtual 3D models for histology education. © 2015 American Association of Anatomists.

Mutations of Photosystem II D1 Protein That Empower Efficient Phenotypes of Chlamydomonas reinhardtii under Extreme Environment in Space

PubMed Central

Lambreva, Maya D.; Antonacci, Amina; Pastorelli, Sandro; Bertalan, Ivo; Johanningmeier, Udo; Mattoo, Autar K.

2013-01-01

Space missions have enabled testing how microorganisms, animals and plants respond to extra-terrestrial, complex and hazardous environment in space. Photosynthetic organisms are thought to be relatively more prone to microgravity, weak magnetic field and cosmic radiation because oxygenic photosynthesis is intimately associated with capture and conversion of light energy into chemical energy, a process that has adapted to relatively less complex and contained environment on Earth. To study the direct effect of the space environment on the fundamental process of photosynthesis, we sent into low Earth orbit space engineered and mutated strains of the unicellular green alga, Chlamydomonas reinhardtii, which has been widely used as a model of photosynthetic organisms. The algal mutants contained specific amino acid substitutions in the functionally important regions of the pivotal Photosystem II (PSII) reaction centre D1 protein near the QB binding pocket and in the environment surrounding Tyr-161 (YZ) electron acceptor of the oxygen-evolving complex. Using real-time measurements of PSII photochemistry, here we show that during the space flight while the control strain and two D1 mutants (A250L and V160A) were inefficient in carrying out PSII activity, two other D1 mutants, I163N and A251C, performed efficient photosynthesis, and actively re-grew upon return to Earth. Mimicking the neutron irradiation component of cosmic rays on Earth yielded similar results. Experiments with I163N and A251C D1 mutants performed on ground showed that they are better able to modulate PSII excitation pressure and have higher capacity to reoxidize the QA − state of the primary electron acceptor. These results highlight the contribution of D1 conformation in relation to photosynthesis and oxygen production in space. PMID:23691201

Evaluation of conditions along the grounding line of temperate marine glaciers: An example from Muir Inlet, Glacier Bay, Alaska

USGS Publications Warehouse

Seramur, K.C.; Powell, R.D.; Carlson, P.R.

1997-01-01

In the marine environment, stability of the glacier terminus and the location of subglacial streams are the dominant controls on the distribution of grounding-line deposits within morainal banks. A morainal bank complex in Muir Inlet, Glacier Bay, SE Alaska, is used to develop a model of terminus stability and location of subglacial streams along the grounding line of temperate marine glaciers. This model can be used to interpret former grounding-line conditions in other glacimarine settings from the facies architecture within morainal bank deposits. The Muir Inlet morainal bank complex was deposited between 1860 A.D. and 1899 A.D., and historical observations provide a record of terminus positions, glacial retreat rates and sedimentary sources. These data are used to reconstruct the depositional environment and to develop a correlation between sedimentary facies and conditions along the grounding line. Four seismic facies identified on the high-resolution seismic-reflection profiles are used to interpret sedimentary facies within the morainal bank complex. Terminus stability is interpreted from the distribution of sedimentary facies within three distinct submarine geomorphic features, a grounding-line fan; stratified ridges, and a field of push ridges. The grounding-line fan was deposited along a stable terminus and is represented on seismic-reflection profiles by two distinct seismic facies, a proximal and a distal fan facies. The proximal fan facies was deposited at the efflux of subglacial streams and indicates the location of former glacifluvial discharges into the sea. Stratified ridges formed as a result of the influence of a quasi-stable terminus on the distribution of sedimentary facies along the grounding line. A field of push ridges formed along the grounding line of an unstable terminus that completely reworked the grounding-line deposits through glacitectonic deformation. Between 1860 A.D. and 1899 A.D. (39 years), 8.96 x 108 m3 of sediment were deposited within the Muir Inlet morainal bank complex at an average annual sediment accumulation rate of 2.3 x 107 m3/a. This rate represents the annual sediment production capacity of the glacier when the Muir Inlet drainage basin is filled with glacial ice.

Robust pedestrian detection and tracking from a moving vehicle

NASA Astrophysics Data System (ADS)

Tuong, Nguyen Xuan; Müller, Thomas; Knoll, Alois

2011-01-01

In this paper, we address the problem of multi-person detection, tracking and distance estimation in a complex scenario using multi-cameras. Specifically, we are interested in a vision system for supporting the driver in avoiding any unwanted collision with the pedestrian. We propose an approach using Histograms of Oriented Gradients (HOG) to detect pedestrians on static images and a particle filter as a robust tracking technique to follow targets from frame to frame. Because the depth map requires expensive computation, we extract depth information of targets using Direct Linear Transformation (DLT) to reconstruct 3D-coordinates of correspondent points found by running Speeded Up Robust Features (SURF) on two input images. Using the particle filter the proposed tracker can efficiently handle target occlusions in a simple background environment. However, to achieve reliable performance in complex scenarios with frequent target occlusions and complex cluttered background, results from the detection module are integrated to create feedback and recover the tracker from tracking failures due to the complexity of the environment and target appearance model variability. The proposed approach is evaluated on different data sets both in a simple background scenario and a cluttered background environment. The result shows that, by integrating detector and tracker, a reliable and stable performance is possible even if occlusion occurs frequently in highly complex environment. A vision-based collision avoidance system for an intelligent car, as a result, can be achieved.

3D Volumetric Strain Modelling of Eruptions at Soufrière Hills Volcano Montserrat

NASA Astrophysics Data System (ADS)

Young, N. K.; Gottsmann, J.

2015-12-01

Volumetric strain data has captured a number of Vulcanian explosions at Soufrière Hills Volcano, Montserrat, which involve the uppermost part of the magmatic system. We previously used volumetric strain data from during one of these explosions to elucidate the geometry of the shallow plumbing system and crustal mechanics at Montserrat for mechanically plausible depressurisation amplitudes. Our results from both forward and inverse 2D models found that it was necessary to incorporate a mechanically weak shallow crust and mechanically compliant halo of material around the highest part of the SHV magmatic system i.e. the conduit, in order to implement geologically realistic conditions of depressurisation and rock strength. However, this model lacks complexity that cannot be implemented in a 2D environment. Here, in the first study of its kind, we use Finite Element Analysis of volumetric strain data in a 3D domain incorporating topography and mechanical complexities as imaged by seismic and gravimetric data. Our model implements topography from a DEM covering the island and surrounding bathymetry and include the mechanically stiff extinct volcanic cores of the Silver Hills and the Centre Hills. Here we present our preliminary findings from the 3D strain modelling and the effect of the extinct volcanic cores on strain partitioning on Montserrat.

Estimation of electromagnetic dosimetric values from non-ionizing radiofrequency fields in an indoor commercial airplane environment.

PubMed

Aguirre, Erik; Arpón, Javier; Azpilicueta, Leire; López, Peio; de Miguel, Silvia; Ramos, Victoria; Falcone, Francisco

2014-12-01

In this article, the impact of topology as well as morphology of a complex indoor environment such as a commercial aircraft in the estimation of dosimetric assessment is presented. By means of an in-house developed deterministic 3D ray-launching code, estimation of electric field amplitude as a function of position for the complete volume of a commercial passenger airplane is obtained. Estimation of electromagnetic field exposure in this environment is challenging, due to the complexity and size of the scenario, as well as to the large metallic content, giving rise to strong multipath components. By performing the calculation with a deterministic technique, the complete scenario can be considered with an optimized balance between accuracy and computational cost. The proposed method can aid in the assessment of electromagnetic dosimetry in the future deployment of embarked wireless systems in commercial aircraft.

VEVI: A Virtual Reality Tool For Robotic Planetary Explorations

NASA Technical Reports Server (NTRS)

Piguet, Laurent; Fong, Terry; Hine, Butler; Hontalas, Phil; Nygren, Erik

1994-01-01

The Virtual Environment Vehicle Interface (VEVI), developed by the NASA Ames Research Center's Intelligent Mechanisms Group, is a modular operator interface for direct teleoperation and supervisory control of robotic vehicles. Virtual environments enable the efficient display and visualization of complex data. This characteristic allows operators to perceive and control complex systems in a natural fashion, utilizing the highly-evolved human sensory system. VEVI utilizes real-time, interactive, 3D graphics and position / orientation sensors to produce a range of interface modalities from the flat panel (windowed or stereoscopic) screen displays to head mounted/head-tracking stereo displays. The interface provides generic video control capability and has been used to control wheeled, legged, air bearing, and underwater vehicles in a variety of different environments. VEVI was designed and implemented to be modular, distributed and easily operated through long-distance communication links, using a communication paradigm called SYNERGY.

Geomorphometric analysis of cave ceiling channels mapped with 3-D terrestrial laser scanning

NASA Astrophysics Data System (ADS)

Gallay, Michal; Hochmuth, Zdenko; Kaňuk, Ján; Hofierka, Jaroslav

2016-05-01

The change of hydrological conditions during the evolution of caves in carbonate rocks often results in a complex subterranean geomorphology, which comprises specific landforms such as ceiling channels, anastomosing half tubes, or speleothems organized vertically in different levels. Studying such complex environments traditionally requires tedious mapping; however, this is being replaced with terrestrial laser scanning technology. Laser scanning overcomes the problem of reaching high ceilings, providing new options to map underground landscapes with unprecedented level of detail and accuracy. The acquired point cloud can be handled conveniently with dedicated software, but applying traditional geomorphometry to analyse the cave surface is limited. This is because geomorphometry has been focused on parameterization and analysis of surficial terrain. The theoretical and methodological concept has been based on two-dimensional (2-D) scalar fields, which are sufficient for most cases of the surficial terrain. The terrain surface is modelled with a bivariate function of altitude (elevation) and represented by a raster digital elevation model. However, the cave is a 3-D entity; therefore, a different approach is required for geomorphometric analysis. In this paper, we demonstrate the benefits of high-resolution cave mapping and 3-D modelling to better understand the palaeohydrography of the Domica cave in Slovakia. This methodological approach adopted traditional geomorphometric methods in a unique manner and also new methods used in 3-D computer graphics, which can be applied to study other 3-D geomorphological forms.

Recognition Of Complex Three Dimensional Objects Using Three Dimensional Moment Invariants

NASA Astrophysics Data System (ADS)

Sadjadi, Firooz A.

1985-01-01

A technique for the recognition of complex three dimensional objects is presented. The complex 3-D objects are represented in terms of their 3-D moment invariants, algebraic expressions that remain invariant independent of the 3-D objects' orientations and locations in the field of view. The technique of 3-D moment invariants has been used successfully for simple 3-D object recognition in the past. In this work we have extended this method for the representation of more complex objects. Two complex objects are represented digitally; their 3-D moment invariants have been calculated, and then the invariancy of these 3-D invariant moment expressions is verified by changing the orientation and the location of the objects in the field of view. The results of this study have significant impact on 3-D robotic vision, 3-D target recognition, scene analysis and artificial intelligence.

Three Dimensional Urban Characterization by IFSAR Measurements

NASA Technical Reports Server (NTRS)

Gamba, P.; Houshmand, B.

1998-01-01

In this paper a machine vision approach is applied to Interferometric Synthetic Aperture Radars (IFSAR) data to extract the most relevant built structures in a dense urban environment. The algorithm tries to cluster primitives (line segments) into more complex surfaces (planes) to approximate the 3D shape of these objects. Very interesting results starting from TOPSAR data recorded over S, Monica are presented.

ABLEPathPlanner library for Umbra

DOE Office of Scientific and Technical Information (OSTI.GOV)

Oppel III, Fred J; Xavier, Patrick G.; Gottlieb, Eric Joseph

Umbra contains a flexible, modular path planner that is used to simulate complex entity behaviors moving within 3D terrain environments that include buildings, barriers, roads, bridges, fences, and a variety of other terrain features (water, vegetation, slope, etc…). The path planning algorithm is a critical component required to execute these tactical behaviors to provide realistic entity movement and provide efficient system computing performance.

Evaluating mental workload of two-dimensional and three-dimensional visualization for anatomical structure localization.

PubMed

Foo, Jung-Leng; Martinez-Escobar, Marisol; Juhnke, Bethany; Cassidy, Keely; Hisley, Kenneth; Lobe, Thom; Winer, Eliot

2013-01-01

Visualization of medical data in three-dimensional (3D) or two-dimensional (2D) views is a complex area of research. In many fields 3D views are used to understand the shape of an object, and 2D views are used to understand spatial relationships. It is unclear how 2D/3D views play a role in the medical field. Using 3D views can potentially decrease the learning curve experienced with traditional 2D views by providing a whole representation of the patient's anatomy. However, there are challenges with 3D views compared with 2D. This current study expands on a previous study to evaluate the mental workload associated with both 2D and 3D views. Twenty-five first-year medical students were asked to localize three anatomical structures--gallbladder, celiac trunk, and superior mesenteric artery--in either 2D or 3D environments. Accuracy and time were taken as the objective measures for mental workload. The NASA Task Load Index (NASA-TLX) was used as a subjective measure for mental workload. Results showed that participants viewing in 3D had higher localization accuracy and a lower subjective measure of mental workload, specifically, the mental demand component of the NASA-TLX. Results from this study may prove useful for designing curricula in anatomy education and improving training procedures for surgeons.

Neuronize: a tool for building realistic neuronal cell morphologies

PubMed Central

Brito, Juan P.; Mata, Susana; Bayona, Sofia; Pastor, Luis; DeFelipe, Javier; Benavides-Piccione, Ruth

2013-01-01

This study presents a tool, Neuronize, for building realistic three-dimensional models of neuronal cells from the morphological information extracted through computer-aided tracing applications. Neuronize consists of a set of methods designed to build 3D neural meshes that approximate the cell membrane at different resolution levels, allowing a balance to be reached between the complexity and the quality of the final model. The main contribution of the present study is the proposal of a novel approach to build a realistic and accurate 3D shape of the soma from the incomplete information stored in the digitally traced neuron, which usually consists of a 2D cell body contour. This technique is based on the deformation of an initial shape driven by the position and thickness of the first order dendrites. The addition of a set of spines along the dendrites completes the model, building a final 3D neuronal cell suitable for its visualization in a wide range of 3D environments. PMID:23761740

Neuronize: a tool for building realistic neuronal cell morphologies.

PubMed

Brito, Juan P; Mata, Susana; Bayona, Sofia; Pastor, Luis; Defelipe, Javier; Benavides-Piccione, Ruth

2013-01-01

This study presents a tool, Neuronize, for building realistic three-dimensional models of neuronal cells from the morphological information extracted through computer-aided tracing applications. Neuronize consists of a set of methods designed to build 3D neural meshes that approximate the cell membrane at different resolution levels, allowing a balance to be reached between the complexity and the quality of the final model. The main contribution of the present study is the proposal of a novel approach to build a realistic and accurate 3D shape of the soma from the incomplete information stored in the digitally traced neuron, which usually consists of a 2D cell body contour. This technique is based on the deformation of an initial shape driven by the position and thickness of the first order dendrites. The addition of a set of spines along the dendrites completes the model, building a final 3D neuronal cell suitable for its visualization in a wide range of 3D environments.

An Improved Indoor Positioning System Using RGB-D Cameras and Wireless Networks for Use in Complex Environments.

PubMed

Duque Domingo, Jaime; Cerrada, Carlos; Valero, Enrique; Cerrada, Jose A

2017-10-20

This work presents an Indoor Positioning System to estimate the location of people navigating in complex indoor environments. The developed technique combines WiFi Positioning Systems and depth maps , delivering promising results in complex inhabited environments, consisting of various connected rooms, where people are freely moving. This is a non-intrusive system in which personal information about subjects is not needed and, although RGB-D cameras are installed in the sensing area, users are only required to carry their smart-phones. In this article, the methods developed to combine the above-mentioned technologies and the experiments performed to test the system are detailed. The obtained results show a significant improvement in terms of accuracy and performance with respect to previous WiFi-based solutions as well as an extension in the range of operation.

Spectral Characterization and 3D Molecular Modeling Studies of Metal Complexes Involving the O, N-Donor Environment of Quinazoline-4(3H)-one Schiff Base and Their Biological Studies

PubMed Central

Siddappa, Kuruba; Mane, Sunilkumar B.

2014-01-01

A simple condensation of 3-amino-2-methylquinazoline-4-one with 2-hydroxy-1-naphthaldehyde produced new tridentate ONO donor Schiff base ligand with efficient yield. The structural characterization of ligand and its Cu(II), Ni(II), Co(II), Mn(II), Zn(II), and Cd(II) complexes were achieved by the aid of elemental analysis, spectral characterization such as (UV-visible, IR, NMR, mass, and ESR), and magnetic data. The analytical and spectroscopic studies suggest the octahedral geometries of Cu(II), Co(II), Ni(II) and Mn(II) complexes and tetrahedral geometry of Zn(II) and Cd(II) complexes with the tridentate ONO Schiff base ligand. Furthermore, the conclusions drawn from these studies afford further support to the mode of bonding discussed on the basis of their 3D molecular modeling studies by considering different bond lengths, bond angles, and bond distance. The ligand and its metal complexes evaluated for their antimicrobial activity against Staphylococcus aureus (MTCC number 7443), Bacillus subtilis (MTCC number 9878), Escherichia coli (MTCC number 1698), Aspergillus niger (MTCC number 281), and Aspergillus flavus (MTCC number 277). The MIC of these compounds was found to be most active at 10 μg/mL concentration in inhibiting the growth of the tested organisms. The DNA cleavage activity of all the complexes was studied by gel electrophoresis method. PMID:24678278

3D cancer cell migration in a confined matrix

NASA Astrophysics Data System (ADS)

Alobaidi, Amani; Sun, Bo

Cancer cell migration is widely studied in 2D motion, which does not mimic the invasion processes in vivo. More recently, 3D cell migration studies have been performed. The ability of cancer cells to migrate within the extracellular matrix depends on the physical and biochemical features of the extracellular matrix. We present a model of cell motility in confined matrix geometry. The aim of the study is to study cancer migration in collagen matrix, as a soft tissue, to investigate their motility within the confined and surrounding collagen environment. Different collagen concentrations have been used to show the ability of these cancer cells to move through such a complex structure by measuring Cancer cell migration velocity as well as the displacement. Graduate student physics department.

Clinically Normal Stereopsis Does Not Ensure Performance Benefit from Stereoscopic 3D Depth Cues

DTIC Science & Technology

2014-10-28

Stereopsis, Binocular Vision, Optometry , Depth Perception, 3D vision, 3D human factors, Stereoscopic displays, S3D, Virtual environment 16...Binocular Vision, Optometry , Depth Perception, 3D vision, 3D human factors, Stereoscopic displays, S3D, Virtual environment 1 Distribution A: Approved

Application of Integration of HBIM and VR Technology to 3D Immersive Digital Management—Take Han Type Traditional Architecture as an Example

NASA Astrophysics Data System (ADS)

Lin, Y.-C.

2017-08-01

HBIM technology makes great contributions to 3D digital preservation and management of the existing traditional architectures, and VR technology has also been gradually emphasized by 3D users in recent years, especially 3D immersive situation makes users more likely to experience the real space field. Taking Han type traditional architecture with relatively complex geometrical structure as an example, this research carries out digital preservation through HBIM technology and tries to switch to VR platform to allow users to enter 3D immersive scene for management and display. It is shown in the research results that the application of integration of HBIM and VR technology to Han type traditional architecture needs to consider 3D digital model of the architecture, and the number of polygon shall be controlled below about 2 million, which can make the operation in VR environment more smooth; the integration of two technologies can achieve the purpose of 3D immersive digital management, which can provide the humanized application close to the real experience for the display of subsequent management of ancient relics and architectural aesthetics.

Immersive Interaction, Manipulation and Analysis of Large 3D Datasets for Planetary and Earth Sciences

NASA Astrophysics Data System (ADS)

Pariser, O.; Calef, F.; Manning, E. M.; Ardulov, V.

2017-12-01

We will present implementation and study of several use-cases of utilizing Virtual Reality (VR) for immersive display, interaction and analysis of large and complex 3D datasets. These datasets have been acquired by the instruments across several Earth, Planetary and Solar Space Robotics Missions. First, we will describe the architecture of the common application framework that was developed to input data, interface with VR display devices and program input controllers in various computing environments. Tethered and portable VR technologies will be contrasted and advantages of each highlighted. We'll proceed to presenting experimental immersive analytics visual constructs that enable augmentation of 3D datasets with 2D ones such as images and statistical and abstract data. We will conclude by presenting comparative analysis with traditional visualization applications and share the feedback provided by our users: scientists and engineers.

3D exploitation of large urban photo archives

NASA Astrophysics Data System (ADS)

Cho, Peter; Snavely, Noah; Anderson, Ross

2010-04-01

Recent work in computer vision has demonstrated the potential to automatically recover camera and scene geometry from large collections of uncooperatively-collected photos. At the same time, aerial ladar and Geographic Information System (GIS) data are becoming more readily accessible. In this paper, we present a system for fusing these data sources in order to transfer 3D and GIS information into outdoor urban imagery. Applying this system to 1000+ pictures shot of the lower Manhattan skyline and the Statue of Liberty, we present two proof-of-concept examples of geometry-based photo enhancement which are difficult to perform via conventional image processing: feature annotation and image-based querying. In these examples, high-level knowledge projects from 3D world-space into georegistered 2D image planes and/or propagates between different photos. Such automatic capabilities lay the groundwork for future real-time labeling of imagery shot in complex city environments by mobile smart phones.

Model-based adaptive 3D sonar reconstruction in reverberating environments.

PubMed

Saucan, Augustin-Alexandru; Sintes, Christophe; Chonavel, Thierry; Caillec, Jean-Marc Le

2015-10-01

In this paper, we propose a novel model-based approach for 3D underwater scene reconstruction, i.e., bathymetry, for side scan sonar arrays in complex and highly reverberating environments like shallow water areas. The presence of multipath echoes and volume reverberation generates false depth estimates. To improve the resulting bathymetry, this paper proposes and develops an adaptive filter, based on several original geometrical models. This multimodel approach makes it possible to track and separate the direction of arrival trajectories of multiple echoes impinging the array. Echo tracking is perceived as a model-based processing stage, incorporating prior information on the temporal evolution of echoes in order to reject cluttered observations generated by interfering echoes. The results of the proposed filter on simulated and real sonar data showcase the clutter-free and regularized bathymetric reconstruction. Model validation is carried out with goodness of fit tests, and demonstrates the importance of model-based processing for bathymetry reconstruction.

Explore the virtual side of earth science

USGS Publications Warehouse

,

1998-01-01

Scientists have always struggled to find an appropriate technology that could represent three-dimensional (3-D) data, facilitate dynamic analysis, and encourage on-the-fly interactivity. In the recent past, scientific visualization has increased the scientist's ability to visualize information, but it has not provided the interactive environment necessary for rapidly changing the model or for viewing the model in ways not predetermined by the visualization specialist. Virtual Reality Modeling Language (VRML 2.0) is a new environment for visualizing 3-D information spaces and is accessible through the Internet with current browser technologies. Researchers from the U.S. Geological Survey (USGS) are using VRML as a scientific visualization tool to help convey complex scientific concepts to various audiences. Kevin W. Laurent, computer scientist, and Maura J. Hogan, technical information specialist, have created a collection of VRML models available through the Internet at Virtual Earth Science (virtual.er.usgs.gov).

Instructional Designers' Media Selection Practices for Distributed Problem-Based Learning Environments

ERIC Educational Resources Information Center

Fells, Stephanie

2012-01-01

The design of online or distributed problem-based learning (dPBL) is a nascent, complex design problem. Instructional designers are challenged to effectively unite the constructivist principles of problem-based learning (PBL) with appropriate media in order to create quality dPBL environments. While computer-mediated communication (CMC) tools and…

Molecular modeling of biomolecules by paramagnetic NMR and computational hybrid methods.

PubMed

Pilla, Kala Bharath; Gaalswyk, Kari; MacCallum, Justin L

2017-11-01

The 3D atomic structures of biomolecules and their complexes are key to our understanding of biomolecular function, recognition, and mechanism. However, it is often difficult to obtain structures, particularly for systems that are complex, dynamic, disordered, or exist in environments like cell membranes. In such cases sparse data from a variety of paramagnetic NMR experiments offers one possible source of structural information. These restraints can be incorporated in computer modeling algorithms that can accurately translate the sparse experimental data into full 3D atomic structures. In this review, we discuss various types of paramagnetic NMR/computational hybrid modeling techniques that can be applied to successful modeling of not only the atomic structure of proteins but also their interacting partners. This article is part of a Special Issue entitled: Biophysics in Canada, edited by Lewis Kay, John Baenziger, Albert Berghuis and Peter Tieleman. Copyright © 2017 Elsevier B.V. All rights reserved.

Identification and location of catenary insulator in complex background based on machine vision

NASA Astrophysics Data System (ADS)

Yao, Xiaotong; Pan, Yingli; Liu, Li; Cheng, Xiao

2018-04-01

It is an important premise to locate insulator precisely for fault detection. Current location algorithms for insulator under catenary checking images are not accurate, a target recognition and localization method based on binocular vision combined with SURF features is proposed. First of all, because of the location of the insulator in complex environment, using SURF features to achieve the coarse positioning of target recognition; then Using binocular vision principle to calculate the 3D coordinates of the object which has been coarsely located, realization of target object recognition and fine location; Finally, Finally, the key is to preserve the 3D coordinate of the object's center of mass, transfer to the inspection robot to control the detection position of the robot. Experimental results demonstrate that the proposed method has better recognition efficiency and accuracy, can successfully identify the target and has a define application value.

Robust position estimation of a mobile vehicle

NASA Astrophysics Data System (ADS)

Conan, Vania; Boulanger, Pierre; Elgazzar, Shadia

1994-11-01

The ability to estimate the position of a mobile vehicle is a key task for navigation over large distances in complex indoor environments such as nuclear power plants. Schematics of the plants are available, but they are incomplete, as real settings contain many objects, such as pipes, cables or furniture, that mask part of the model. The position estimation method described in this paper matches 3-D data with a simple schematic of a plant. It is basically independent of odometry information and viewpoint, robust to noisy data and spurious points and largely insensitive to occlusions. The method is based on a hypothesis/verification paradigm and its complexity is polynomial; it runs in (Omicron) (m4n4), where m represents the number of model patches and n the number of scene patches. Heuristics are presented to speed up the algorithm. Results on real 3-D data show good behavior even when the scene is very occluded.

Design and modelling of a 3D compliant leg for Bioloid

NASA Astrophysics Data System (ADS)

Couto, Mafalda; Santos, Cristina; Machado, José

2012-09-01

In the growing field of rehabilitation robotics, the modelling of a real robot is a complex and passionate challenge. On the crossing point of mechanics, physics and computer-science, the development of a complete 3D model involves the knowledge of the different physic properties, for an accurate simulation. In this paper, it is proposed the design of an efficient three-dimensional model of the quadruped Bioloid robot setting segmented pantographic legs, in order to actively retract the quadruped legs during locomotion and minimizing large forces due to shocks, such that the robot is able to safely and dynamically interact with the user or the environment.

Interactive Computer-Enhanced Remote Viewing System (ICERVS): Final report, November 1994--September 1996

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

1997-05-01

The Interactive Computer-Enhanced Remote Viewing System (ICERVS) is a software tool for complex three-dimensional (3-D) visualization and modeling. Its primary purpose is to facilitate the use of robotic and telerobotic systems in remote and/or hazardous environments, where spatial information is provided by 3-D mapping sensors. ICERVS provides a robust, interactive system for viewing sensor data in 3-D and combines this with interactive geometric modeling capabilities that allow an operator to construct CAD models to match the remote environment. Part I of this report traces the development of ICERVS through three evolutionary phases: (1) development of first-generation software to render orthogonalmore » view displays and wireframe models; (2) expansion of this software to include interactive viewpoint control, surface-shaded graphics, material (scalar and nonscalar) property data, cut/slice planes, color and visibility mapping, and generalized object models; (3) demonstration of ICERVS as a tool for the remediation of underground storage tanks (USTs) and the dismantlement of contaminated processing facilities. Part II of this report details the software design of ICERVS, with particular emphasis on its object-oriented architecture and user interface.« less

Augmented reality and photogrammetry: A synergy to visualize physical and virtual city environments

NASA Astrophysics Data System (ADS)

Portalés, Cristina; Lerma, José Luis; Navarro, Santiago

2010-01-01

Close-range photogrammetry is based on the acquisition of imagery to make accurate measurements and, eventually, three-dimensional (3D) photo-realistic models. These models are a photogrammetric product per se. They are usually integrated into virtual reality scenarios where additional data such as sound, text or video can be introduced, leading to multimedia virtual environments. These environments allow users both to navigate and interact on different platforms such as desktop PCs, laptops and small hand-held devices (mobile phones or PDAs). In very recent years, a new technology derived from virtual reality has emerged: Augmented Reality (AR), which is based on mixing real and virtual environments to boost human interactions and real-life navigations. The synergy of AR and photogrammetry opens up new possibilities in the field of 3D data visualization, navigation and interaction far beyond the traditional static navigation and interaction in front of a computer screen. In this paper we introduce a low-cost outdoor mobile AR application to integrate buildings of different urban spaces. High-accuracy 3D photo-models derived from close-range photogrammetry are integrated in real (physical) urban worlds. The augmented environment that is presented herein requires for visualization a see-through video head mounted display (HMD), whereas user's movement navigation is achieved in the real world with the help of an inertial navigation sensor. After introducing the basics of AR technology, the paper will deal with real-time orientation and tracking in combined physical and virtual city environments, merging close-range photogrammetry and AR. There are, however, some software and complex issues, which are discussed in the paper.

Immune systems are not just for making you feel better: they are for controlling autonomous robots

NASA Astrophysics Data System (ADS)

Rosenblum, Mark

2005-05-01

The typical algorithm for robot autonomous navigation in off-road complex environments involves building a 3D map of the robot's surrounding environment using a 3D sensing modality such as stereo vision or active laser scanning, and generating an instantaneous plan to navigate around hazards. Although there has been steady progress using these methods, these systems suffer from several limitations that cannot be overcome with 3D sensing and planning alone. Geometric sensing alone has no ability to distinguish between compressible and non-compressible materials. As a result, these systems have difficulty in heavily vegetated environments and require sensitivity adjustments across different terrain types. On the planning side, these systems have no ability to learn from their mistakes and avoid problematic environmental situations on subsequent encounters. We have implemented an adaptive terrain classification system based on the Artificial Immune System (AIS) computational model, which is loosely based on the biological immune system, that combines various forms of imaging sensor inputs to produce a "feature labeled" image of the scene categorizing areas as benign or detrimental for autonomous robot navigation. Because of the qualities of the AIS computation model, the resulting system will be able to learn and adapt on its own through interaction with the environment by modifying its interpretation of the sensor data. The feature labeled results from the AIS analysis are inserted into a map and can then be used by a planner to generate a safe route to a goal point. The coupling of diverse visual cues with the malleable AIS computational model will lead to autonomous robotic ground vehicles that require less human intervention for deployment in novel environments and more robust operation as a result of the system's ability to improve its performance through interaction with the environment.

Cell shape characterization and classification with discrete Fourier transforms and self-organizing maps.

PubMed

Kriegel, Fabian L; Köhler, Ralf; Bayat-Sarmadi, Jannike; Bayerl, Simon; Hauser, Anja E; Niesner, Raluca; Luch, Andreas; Cseresnyes, Zoltan

2018-03-01

Cells in their natural environment often exhibit complex kinetic behavior and radical adjustments of their shapes. This enables them to accommodate to short- and long-term changes in their surroundings under physiological and pathological conditions. Intravital multi-photon microscopy is a powerful tool to record this complex behavior. Traditionally, cell behavior is characterized by tracking the cells' movements, which yields numerous parameters describing the spatiotemporal characteristics of cells. Cells can be classified according to their tracking behavior using all or a subset of these kinetic parameters. This categorization can be supported by the a priori knowledge of experts. While such an approach provides an excellent starting point for analyzing complex intravital imaging data, faster methods are required for automated and unbiased characterization. In addition to their kinetic behavior, the 3D shape of these cells also provide essential clues about the cells' status and functionality. New approaches that include the study of cell shapes as well may also allow the discovery of correlations amongst the track- and shape-describing parameters. In the current study, we examine the applicability of a set of Fourier components produced by Discrete Fourier Transform (DFT) as a tool for more efficient and less biased classification of complex cell shapes. By carrying out a number of 3D-to-2D projections of surface-rendered cells, the applied method reduces the more complex 3D shape characterization to a series of 2D DFTs. The resulting shape factors are used to train a Self-Organizing Map (SOM), which provides an unbiased estimate for the best clustering of the data, thereby characterizing groups of cells according to their shape. We propose and demonstrate that such shape characterization is a powerful addition to, or a replacement for kinetic analysis. This would make it especially useful in situations where live kinetic imaging is less practical or not possible at all. © 2017 International Society for Advancement of Cytometry. © 2017 International Society for Advancement of Cytometry.

3D Printed Abdominal Aortic Aneurysm Phantom for Image Guided Surgical Planning with a Patient Specific Fenestrated Endovascular Graft System

PubMed Central

Meess, Karen M.; Izzo, Richard L.; Dryjski, Maciej L.; Curl, Richard E.; Harris, Linda M.; Springer, Michael; Siddiqui, Adnan H.; Rudin, Stephen; Ionita, Ciprian N.

2017-01-01

Following new trends in precision medicine, Juxatarenal Abdominal Aortic Aneurysm (JAAA) treatment has been enabled by using patient-specific fenestrated endovascular grafts. The X-ray guided procedure requires precise orientation of multiple modular endografts within the arteries confirmed via radiopaque markers. Patient-specific 3D printed phantoms could familiarize physicians with complex procedures and new devices in a risk-free simulation environment to avoid periprocedural complications and improve training. Using the Vascular Modeling Toolkit (VMTK), 3D Data from a CTA imaging of a patient scheduled for Fenestrated EndoVascular Aortic Repair (FEVAR) was segmented to isolate the aortic lumen, thrombus, and calcifications. A stereolithographic mesh (STL) was generated and then modified in Autodesk MeshMixer for fabrication via a Stratasys Eden 260 printer in a flexible photopolymer to simulate arterial compliance. Fluoroscopic guided simulation of the patient-specific FEVAR procedure was performed by interventionists using all demonstration endografts and accessory devices. Analysis compared treatment strategy between the planned procedure, the simulation procedure, and the patient procedure using a derived scoring scheme. Results With training on the patient-specific 3D printed AAA phantom, the clinical team optimized their procedural strategy. Anatomical landmarks and all devices were visible under x-ray during the simulation mimicking the clinical environment. The actual patient procedure went without complications. Conclusions With advances in 3D printing, fabrication of patient specific AAA phantoms is possible. Simulation with 3D printed phantoms shows potential to inform clinical interventional procedures in addition to CTA diagnostic imaging. PMID:28638171

3D Printed Abdominal Aortic Aneurysm Phantom for Image Guided Surgical Planning with a Patient Specific Fenestrated Endovascular Graft System.

PubMed

Meess, Karen M; Izzo, Richard L; Dryjski, Maciej L; Curl, Richard E; Harris, Linda M; Springer, Michael; Siddiqui, Adnan H; Rudin, Stephen; Ionita, Ciprian N

2017-02-11

Following new trends in precision medicine, Juxatarenal Abdominal Aortic Aneurysm (JAAA) treatment has been enabled by using patient-specific fenestrated endovascular grafts. The X-ray guided procedure requires precise orientation of multiple modular endografts within the arteries confirmed via radiopaque markers. Patient-specific 3D printed phantoms could familiarize physicians with complex procedures and new devices in a risk-free simulation environment to avoid periprocedural complications and improve training. Using the Vascular Modeling Toolkit (VMTK), 3D Data from a CTA imaging of a patient scheduled for Fenestrated EndoVascular Aortic Repair (FEVAR) was segmented to isolate the aortic lumen, thrombus, and calcifications. A stereolithographic mesh (STL) was generated and then modified in Autodesk MeshMixer for fabrication via a Stratasys Eden 260 printer in a flexible photopolymer to simulate arterial compliance. Fluoroscopic guided simulation of the patient-specific FEVAR procedure was performed by interventionists using all demonstration endografts and accessory devices. Analysis compared treatment strategy between the planned procedure, the simulation procedure, and the patient procedure using a derived scoring scheme. With training on the patient-specific 3D printed AAA phantom, the clinical team optimized their procedural strategy. Anatomical landmarks and all devices were visible under x-ray during the simulation mimicking the clinical environment. The actual patient procedure went without complications. With advances in 3D printing, fabrication of patient specific AAA phantoms is possible. Simulation with 3D printed phantoms shows potential to inform clinical interventional procedures in addition to CTA diagnostic imaging.

Reproducing the internal and external anatomy of fossil bones: Two new automatic digital tools.

PubMed

Profico, Antonio; Schlager, Stefan; Valoriani, Veronica; Buzi, Costantino; Melchionna, Marina; Veneziano, Alessio; Raia, Pasquale; Moggi-Cecchi, Jacopo; Manzi, Giorgio

2018-04-21

We present two new automatic tools, developed under the R environment, to reproduce the internal and external structures of bony elements. The first method, Computer-Aided Laser Scanner Emulator (CA-LSE), provides the reconstruction of the external portions of a 3D mesh by simulating the action of a laser scanner. The second method, Automatic Segmentation Tool for 3D objects (AST-3D), performs the digital reconstruction of anatomical cavities. We present the application of CA-LSE and AST-3D methods to different anatomical remains, highly variable in terms of shape, size and structure: a modern human skull, a malleus bone, and a Neanderthal deciduous tooth. Both methods are developed in the R environment and embedded in the packages "Arothron" and "Morpho," where both the codes and the data are fully available. The application of CA-LSE and AST-3D allows the isolation and manipulation of the internal and external components of the 3D virtual representation of complex bony elements. In particular, we present the output of the four case studies: a complete modern human endocast and the right maxillary sinus, the dental pulp of the Neanderthal tooth and the inner network of blood vessels of the malleus. Both methods demonstrated to be much faster, cheaper, and more accurate than other conventional approaches. The tools we presented are available as add-ons in existing software within the R platform. Because of ease of application, and unrestrained availability of the methods proposed, these tools can be widely used by paleoanthropologists, paleontologists and anatomists. © 2018 Wiley Periodicals, Inc.

3D printed abdominal aortic aneurysm phantom for image guided surgical planning with a patient specific fenestrated endovascular graft system

NASA Astrophysics Data System (ADS)

Meess, Karen M.; Izzo, Richard L.; Dryjski, Maciej L.; Curl, Richard E.; Harris, Linda M.; Springer, Michael; Siddiqui, Adnan H.; Rudin, Stephen; Ionita, Ciprian N.

2017-03-01

Following new trends in precision medicine, Juxatarenal Abdominal Aortic Aneurysm (JAAA) treatment has been enabled by using patient-specific fenestrated endovascular grafts. The X-ray guided procedure requires precise orientation of multiple modular endografts within the arteries confirmed via radiopaque markers. Patient-specific 3D printed phantoms could familiarize physicians with complex procedures and new devices in a risk-free simulation environment to avoid periprocedural complications and improve training. Using the Vascular Modeling Toolkit (VMTK), 3D Data from a CTA imaging of a patient scheduled for Fenestrated EndoVascular Aortic Repair (FEVAR) was segmented to isolate the aortic lumen, thrombus, and calcifications. A stereolithographic mesh (STL) was generated and then modified in Autodesk MeshMixer for fabrication via a Stratasys Eden 260 printer in a flexible photopolymer to simulate arterial compliance. Fluoroscopic guided simulation of the patient-specific FEVAR procedure was performed by interventionists using all demonstration endografts and accessory devices. Analysis compared treatment strategy between the planned procedure, the simulation procedure, and the patient procedure using a derived scoring scheme. Results: With training on the patient-specific 3D printed AAA phantom, the clinical team optimized their procedural strategy. Anatomical landmarks and all devices were visible under x-ray during the simulation mimicking the clinical environment. The actual patient procedure went without complications. Conclusions: With advances in 3D printing, fabrication of patient specific AAA phantoms is possible. Simulation with 3D printed phantoms shows potential to inform clinical interventional procedures in addition to CTA diagnostic imaging.

Genetic environment of metallo-β-lactamase genes in Pseudomonas aeruginosa isolates from the UK.

PubMed

Wright, Laura L; Turton, Jane F; Hopkins, Katie L; Livermore, David M; Woodford, Neil

2015-12-01

We sought to characterize the genetic environment of blaVIM and blaIMP genes in Pseudomonas aeruginosa isolates from the UK; these included members of six previously described prevalent complexes, A-F, which correspond to international 'high-risk clones', along with diverse strains. Metallo-β-lactamase (MBL)-encoding class 1 integrons were amplified by PCR from 218 P. aeruginosa isolates producing VIM-type (n = 196) or IMP-type (n = 22) enzymes, referred from UK hospital laboratories between 2003 and 2012. The variable regions of selected integrons were sequenced using a primer walking method. One-hundred-and-nineteen isolates had an MBL-encoding integron with the 3' conserved sequence (3'CS), 65 had Tn5090-like 3' regions and 17 had the sul1 gene, but lacked the qacEΔ1 gene; the 3' region could not be amplified using any primer combinations for the remaining 17 isolates. Six integron profiles were each seen in more than five isolates. Predominant integron types were seen amongst isolates belonging to STs 111, 233, 654/964 and 773 (complexes A, C, D and F, respectively), whereas diverse integron profiles were seen in isolates belonging to ST235 (complex B) and ST357 (complex E). In UK P. aeruginosa isolates, MBL genes occur in diverse class 1 integron structures, though commonly with 3' regions containing the classical 3'CS or Tn5090-like regions. Four of the six main clonal complexes, referred from multiple laboratories, carried a predominant integron type, whereas the remaining two had more diverse types. © Crown copyright 2015.

The Propagation of Seismic Waves in the Presence of Strong Elastic Property Contrasts

NASA Astrophysics Data System (ADS)

Saleh, R.; Jeyaraj, R.; Milkereit, B.; Liu, Q.; Valley, B.

2012-12-01

In an active underground mine there are many seismic activities taking place, such as seismic noises, blasts, tremors and microseismic events. In between the activities, the microseismic events are mainly used for monitoring purposes. The frequency content of microseismic events can be up to few KHz, which can result in wavelengths on the order of a few meters in hard rock environment. In an underground mine, considering the presence of both small wavelength and strong elastic contrasts, the simulation of seismic wave propagation is a challenge. With the recent availability of detailed 3D rock property models of mines, in addition to the development of efficient numerical techniques (such as Spectral Element Method (SEM)), and parallel computation facilities, a solution for such a problem is achievable. Most seismic wave scattering studies focus on large scales (>1 km) and weak elastic contrasts (velocity perturbations less than 10%). However, scattering in the presence of small-scale heterogeneities and large elastic contrasts is an area of ongoing research. In a mine environment, the presence of strong contrast discontinuities such as massive ore bodies, tunnels and infrastructure lead to discontinuities of displacement and/or stress tensor components, and have significant impact on the propagation of seismic waves. In order to obtain an accurate image of wave propagation in such a complex media, it is necessary to consider the presence of these discontinuities in numerical models. In this study, the effects of such a contrast are illustrated with 2D/3D modeling and compared with real broadband 3-component seismic data. The real broadband 3-component seismic data will be obtained in one of the Canadian underground mines in Ontario. One of the possible scenarios investigated in this study that may explain the observed complexity in seismic wavefield pattern in hard rock environments is the effect of near field displacements rather than far field. Considering the distribution of seismic sensors in a mine and the presence of seismic events within a mine, the recorded wavefield may represent a near-field displacement, which is not the case for most of seismic studies. The role of receiver characterization on the recorded event near the surface or around fault zones is also investigated. Using 2D/3D modeling, the effects of Vp/Vs variation on vertical and horizontal components of recorded amplitude has been shown.

How paramagnetic and diamagnetic LMOCs detect picric acid from surface water and the intracellular environment: a combined experimental and DFT-D3 study.

PubMed

Ghosh, Pritam; Banerjee, Priyabrata

2016-08-17

Diamagnetic and Paramagnetic Luminescent Metal Organic Complexes (LMOCs) have been reported for Explosive and Pollutant Nitro Aromatic (epNAC) recognition. The diamagnetic complex shows a highly intense AIE induced by NEt3H(+), which disappears after picric acid recognition and subsequently RET will quench the emission intensity. Radical stabilized paramagnetic LMOCs seem to be active but show lower sensing efficiency in comparison with diamagnetic LMOCs. Solution and solid state spectroscopy studies along with DFT-D3 have been executed to enlighten the host guest interaction. Limit of PA detection is ∼250 ppb with a binding constant of 1.2 × 10(5) M(-1). Time-stepping, i.e. intervening in the problem of picric acid recognition from surface water collected from several places of West Bengal, India, has been performed. Mutagenic picric acid has been successfully detected in an aqueous medium inside both prokaryotic and eukaryotic cells at a ppm level using fluorescence microscopy.

Ultra-Rapid 2-D and 3-D Laser Microprinting of Proteins

NASA Astrophysics Data System (ADS)

Scott, Mark Andrew

When viewed under the microscope, biological tissues reveal an exquisite microarchitecture. These complex patterns arise during development, as cells interact with a multitude of chemical and mechanical cues in the surrounding extracellular matrix. Tissue engineers have sought for decades to repair or replace damaged tissue, often relying on porous scaffolds as an artificial extracellular matrix to support cell development. However, these grafts are unable to recapitulate the complexity of the in vivo environment, limiting our ability to regenerate functional tissue. Biomedical engineers have developed several methods for printing two- and three-dimensional patterns of proteins for studying and directing cell development. Of these methods, laser microprinting of proteins has shown the most promise for printing sub-cellular resolution gradients of cues, but the photochemistry remains too slow to enable large-scale applications for screening and therapeutics In this work, we demonstrate a novel high-speed photochemistry based on multi-photon photobleaching of fluorescein, and we build the fastest 2-D and 3-D laser microprinter for proteins to date. First, we show that multiphoton photobleaching of a deoxygenated solution of biotin-4-fluorescein onto a PEG monolayer with acrylate end-group can enable print speeds of almost 20 million pixels per second at 600 nanometer resolution. We discovered that the mechanism of fluorescein photobleaching evolves from a 2-photon to 3- and 4-photon regime at higher laser intensities, unlocking faster printing kinetics. Using this 2-D printing system, we develop a novel triangle-ratchet method for directing the polarization of single hippocampal neurons. This ability to determine which neurite becomes an axon, and which neuritis become dendrites is an essential step for developing defined in vitro neural networks. Next, we modify our multiphoton photobleaching system to print in three dimensions. For the first time, we demonstrate 3-D printing of full length proteins in collagen, fibrin and gelatin methacrylate scaffolds, as well as printing in agarose and agarose methacrylate scaffolds. We also present a novel method for 3-D printing collagen scaffolds at unprecedented speeds, up to 14layers per second, generating complex shapes in seconds with sub-micron resolution. Finally, we demonstrate that 3-D printing of scaffold architecture and protein cues inside the scaffold can be combined, for the first time enabling structures with complex sub-micron architectures and chemical cues for directing development. We believe that the ultra-rapid printing technology presented in this thesis will be a key enabler in the development of complex, artificially engineered tissues and organs. (Copies available exclusively from MIT Libraries, libraries.mit.edu/docs - docs mit.edu)

Multi-Dimensional Simulation of LWR Fuel Behavior in the BISON Fuel Performance Code

NASA Astrophysics Data System (ADS)

Williamson, R. L.; Capps, N. A.; Liu, W.; Rashid, Y. R.; Wirth, B. D.

2016-11-01

Nuclear fuel operates in an extreme environment that induces complex multiphysics phenomena occurring over distances ranging from inter-atomic spacing to meters, and times scales ranging from microseconds to years. To simulate this behavior requires a wide variety of material models that are often complex and nonlinear. The recently developed BISON code represents a powerful fuel performance simulation tool based on its material and physical behavior capabilities, finite-element versatility of spatial representation, and use of parallel computing. The code can operate in full three dimensional (3D) mode, as well as in reduced two dimensional (2D) modes, e.g., axisymmetric radial-axial ( R- Z) or plane radial-circumferential ( R- θ), to suit the application and to allow treatment of global and local effects. A BISON case study was used to illustrate analysis of Pellet Clad Mechanical Interaction failures from manufacturing defects using combined 2D and 3D analyses. The analysis involved commercial fuel rods and demonstrated successful computation of metrics of interest to fuel failures, including cladding peak hoop stress and strain energy density. In comparison with a failure threshold derived from power ramp tests, results corroborate industry analyses of the root cause of the pellet-clad interaction failures and illustrate the importance of modeling 3D local effects around fuel pellet defects, which can produce complex effects including cold spots in the cladding, stress concentrations, and hot spots in the fuel that can lead to enhanced cladding degradation such as hydriding, oxidation, CRUD formation, and stress corrosion cracking.

Multi-Dimensional Simulation of LWR Fuel Behavior in the BISON Fuel Performance Code

DOE PAGES

Williamson, R. L.; Capps, N. A.; Liu, W.; ...

2016-09-27

Nuclear fuel operates in an extreme environment that induces complex multiphysics phenomena occurring over distances ranging from inter-atomic spacing to meters, and times scales ranging from microseconds to years. To simulate this behavior requires a wide variety of material models that are often complex and nonlinear. The recently developed BISON code represents a powerful fuel performance simulation tool based on its material and physical behavior capabilities, finite-element versatility of spatial representation, and use of parallel computing. The code can operate in full three dimensional (3D) mode, as well as in reduced two dimensional (2D) modes, e.g., axisymmetric radial-axial (R-Z) ormore » plane radial-circumferential (R-θ), to suit the application and to allow treatment of global and local effects. A BISON case study was used in this paper to illustrate analysis of Pellet Clad Mechanical Interaction failures from manufacturing defects using combined 2D and 3D analyses. The analysis involved commercial fuel rods and demonstrated successful computation of metrics of interest to fuel failures, including cladding peak hoop stress and strain energy density. Finally, in comparison with a failure threshold derived from power ramp tests, results corroborate industry analyses of the root cause of the pellet-clad interaction failures and illustrate the importance of modeling 3D local effects around fuel pellet defects, which can produce complex effects including cold spots in the cladding, stress concentrations, and hot spots in the fuel that can lead to enhanced cladding degradation such as hydriding, oxidation, CRUD formation, and stress corrosion cracking.« less

Virtual environments from panoramic images

NASA Astrophysics Data System (ADS)

Chapman, David P.; Deacon, Andrew

1998-12-01

A number of recent projects have demonstrated the utility of Internet-enabled image databases for the documentation of complex, inaccessible and potentially hazardous environments typically encountered in the petrochemical and nuclear industries. Unfortunately machine vision and image processing techniques have not, to date, enabled the automatic extraction geometrical data from such images and thus 3D CAD modeling remains an expensive and laborious manual activity. Recent developments in panoramic image capture and presentation offer an alternative intermediate deliverable which, in turn, offers some of the benefits of a 3D model at a fraction of the cost. Panoramic image display tools such as Apple's QuickTime VR (QTVR) and Live Spaces RealVR provide compelling and accessible digital representations of the real world and justifiably claim to 'put the reality in Virtual Reality.' This paper will demonstrate how such technologies can be customized, extended and linked to facility management systems delivered over a corporate intra-net to enable end users to become familiar with remote sites and extract simple dimensional data. In addition strategies for the integration of such images with documents gathered from 2D or 3D CAD and Process and Instrumentation Diagrams (P&IDs) will be described as will techniques for precise 'As-Built' modeling using the calibrated images from which panoramas have been derived and the use of textures from these images to increase the realism of rendered scenes. A number of case studies relating to both nuclear and process engineering will demonstrate the extent to which such solution are scaleable in order to deal with the very large volumes of image data required to fully document the large, complex facilities typical of these industry sectors.

Sorption of Eu(III) on humic acid or fulvic acid bound to hydrous alumina studied by SEM-EDS, XPS, TRLFS, and batch techniques.

PubMed

Tan, X L; Wang, X K; Geckeis, H; Rabung, Th

2008-09-01

To identify the effect of humic acid (HA) and fulvic acid (FA) on the sorption mechanism of Eu(III) on organic--inorganic colloids in the environment at a molecular level, surface adsorbed/ complexed Eu(III) on hydrous alumina, HA-, and FA-hydrous alumina hybrids were characterized by using X-ray photoelectron spectroscopy (XPS) and time-resolved laser fluorescence spectroscopy (TRLFS). The experiments were performed in 0.1 mol/L KNO3 or 0.1 mol/L NaClO4 under ambient conditions. The pH values were varied between 2 and 11 at a fixed Eu(III) concentration of 6.0 x 10(-7) mol/L and 4.3 x 10(-5) mol/L. The different Eu(III)/FA(HA)/hydrous alumina complexes were characterized by their fluorescence emission spectra ((5D0-F1)/ (5D0 --> 7F2)) and binding energy of Eu(III). Inner-sphere surface complexation may contribute mainly to Eu(III) sorption on hydrous alumina, and a ternary surface complex is formed at the HA/ FA-hydrous alumina hybrid surfaces. The sorption and species of Eu(III) in ternary Eu-HA/FA-hydrous alumina systems are not dominated by either HA/FA or hydrous alumina, but are dominated by both HA/FA and hydrous alumina. The results are important for understanding the sorption mechanisms and the nature of surface adsorbed Eu(III) species and trivalent chemical homologues of Eu(III) in the natural environment.

Three-dimensional ocean sensor networks: A survey

NASA Astrophysics Data System (ADS)

Wang, Yu; Liu, Yingjian; Guo, Zhongwen

2012-12-01

The past decade has seen a growing interest in ocean sensor networks because of their wide applications in marine research, oceanography, ocean monitoring, offshore exploration, and defense or homeland security. Ocean sensor networks are generally formed with various ocean sensors, autonomous underwater vehicles, surface stations, and research vessels. To make ocean sensor network applications viable, efficient communication among all devices and components is crucial. Due to the unique characteristics of underwater acoustic channels and the complex deployment environment in three dimensional (3D) ocean spaces, new efficient and reliable communication and networking protocols are needed in design of ocean sensor networks. In this paper, we aim to provide an overview of the most recent advances in network design principles for 3D ocean sensor networks, with focuses on deployment, localization, topology design, and position-based routing in 3D ocean spaces.

Virtual Reconstruction of Lost Architectures: from the Tls Survey to AR Visualization

NASA Astrophysics Data System (ADS)

Quattrini, R.; Pierdicca, R.; Frontoni, E.; Barcaglioni, R.

2016-06-01

The exploitation of high quality 3D models for dissemination of archaeological heritage is currently an investigated topic, although Mobile Augmented Reality platforms for historical architecture are not available, allowing to develop low-cost pipelines for effective contents. The paper presents a virtual anastylosis, starting from historical sources and from 3D model based on TLS survey. Several efforts and outputs in augmented or immersive environments, exploiting this reconstruction, are discussed. The work demonstrates the feasibility of a 3D reconstruction approach for complex architectural shapes starting from point clouds and its AR/VR exploitation, allowing the superimposition with archaeological evidences. Major contributions consist in the presentation and the discussion of a pipeline starting from the virtual model, to its simplification showing several outcomes, comparing also the supported data qualities and advantages/disadvantages due to MAR and VR limitations.

Understanding Immersivity: Image Generation and Transformation Processes in 3D Immersive Environments

PubMed Central

Kozhevnikov, Maria; Dhond, Rupali P.

2012-01-01

Most research on three-dimensional (3D) visual-spatial processing has been conducted using traditional non-immersive 2D displays. Here we investigated how individuals generate and transform mental images within 3D immersive (3DI) virtual environments, in which the viewers perceive themselves as being surrounded by a 3D world. In Experiment 1, we compared participants’ performance on the Shepard and Metzler (1971) mental rotation (MR) task across the following three types of visual presentation environments; traditional 2D non-immersive (2DNI), 3D non-immersive (3DNI – anaglyphic glasses), and 3DI (head mounted display with position and head orientation tracking). In Experiment 2, we examined how the use of different backgrounds affected MR processes within the 3DI environment. In Experiment 3, we compared electroencephalogram data recorded while participants were mentally rotating visual-spatial images presented in 3DI vs. 2DNI environments. Overall, the findings of the three experiments suggest that visual-spatial processing is different in immersive and non-immersive environments, and that immersive environments may require different image encoding and transformation strategies than the two other non-immersive environments. Specifically, in a non-immersive environment, participants may utilize a scene-based frame of reference and allocentric encoding whereas immersive environments may encourage the use of a viewer-centered frame of reference and egocentric encoding. These findings also suggest that MR performed in laboratory conditions using a traditional 2D computer screen may not reflect spatial processing as it would occur in the real world. PMID:22908003

A high-level 3D visualization API for Java and ImageJ.

PubMed

Schmid, Benjamin; Schindelin, Johannes; Cardona, Albert; Longair, Mark; Heisenberg, Martin

2010-05-21

Current imaging methods such as Magnetic Resonance Imaging (MRI), Confocal microscopy, Electron Microscopy (EM) or Selective Plane Illumination Microscopy (SPIM) yield three-dimensional (3D) data sets in need of appropriate computational methods for their analysis. The reconstruction, segmentation and registration are best approached from the 3D representation of the data set. Here we present a platform-independent framework based on Java and Java 3D for accelerated rendering of biological images. Our framework is seamlessly integrated into ImageJ, a free image processing package with a vast collection of community-developed biological image analysis tools. Our framework enriches the ImageJ software libraries with methods that greatly reduce the complexity of developing image analysis tools in an interactive 3D visualization environment. In particular, we provide high-level access to volume rendering, volume editing, surface extraction, and image annotation. The ability to rely on a library that removes the low-level details enables concentrating software development efforts on the algorithm implementation parts. Our framework enables biomedical image software development to be built with 3D visualization capabilities with very little effort. We offer the source code and convenient binary packages along with extensive documentation at http://3dviewer.neurofly.de.

Dissection of C. elegans behavioral genetics in 3-D environments

PubMed Central

Kwon, Namseop; Hwang, Ara B.; You, Young-Jai; V. Lee, Seung-Jae; Ho Je, Jung

2015-01-01

The nematode Caenorhabditis elegans is a widely used model for genetic dissection of animal behaviors. Despite extensive technical advances in imaging methods, it remains challenging to visualize and quantify C. elegans behaviors in three-dimensional (3-D) natural environments. Here we developed an innovative 3-D imaging method that enables quantification of C. elegans behavior in 3-D environments. Furthermore, for the first time, we characterized 3-D-specific behavioral phenotypes of mutant worms that have defects in head movement or mechanosensation. This approach allowed us to reveal previously unknown functions of genes in behavioral regulation. We expect that our 3-D imaging method will facilitate new investigations into genetic basis of animal behaviors in natural 3-D environments. PMID:25955271

Correlative two-photon and serial block face scanning electron microscopy in neuronal tissue using 3D near-infrared branding maps.

PubMed

Lees, Robert M; Peddie, Christopher J; Collinson, Lucy M; Ashby, Michael C; Verkade, Paul

2017-01-01

Linking cellular structure and function has always been a key goal of microscopy, but obtaining high resolution spatial and temporal information from the same specimen is a fundamental challenge. Two-photon (2P) microscopy allows imaging deep inside intact tissue, bringing great insight into the structural and functional dynamics of cells in their physiological environment. At the nanoscale, the complex ultrastructure of a cell's environment in tissue can be reconstructed in three dimensions (3D) using serial block face scanning electron microscopy (SBF-SEM). This provides a snapshot of high resolution structural information pertaining to the shape, organization, and localization of multiple subcellular structures at the same time. The pairing of these two imaging modalities in the same specimen provides key information to relate cellular dynamics to the ultrastructural environment. Until recently, approaches to relocate a region of interest (ROI) in tissue from 2P microscopy for SBF-SEM have been inefficient or unreliable. However, near-infrared branding (NIRB) overcomes this by using the laser from a multiphoton microscope to create fiducial markers for accurate correlation of 2P and electron microscopy (EM) imaging volumes. The process is quick and can be user defined for each sample. Here, to increase the efficiency of ROI relocation, multiple NIRB marks are used in 3D to target ultramicrotomy. A workflow is described and discussed to obtain a data set for 3D correlated light and electron microscopy, using three different preparations of brain tissue as examples. Copyright © 2017 Elsevier Inc. All rights reserved.

Visualization of volumetric seismic data

NASA Astrophysics Data System (ADS)

Spickermann, Dela; Böttinger, Michael; Ashfaq Ahmed, Khawar; Gajewski, Dirk

2015-04-01

Mostly driven by demands of high quality subsurface imaging, highly specialized tools and methods have been developed to support the processing, visualization and interpretation of seismic data. 3D seismic data acquisition and 4D time-lapse seismic monitoring are well-established techniques in academia and industry, producing large amounts of data to be processed, visualized and interpreted. In this context, interactive 3D visualization methods proved to be valuable for the analysis of 3D seismic data cubes - especially for sedimentary environments with continuous horizons. In crystalline and hard rock environments, where hydraulic stimulation techniques may be applied to produce geothermal energy, interpretation of the seismic data is a more challenging problem. Instead of continuous reflection horizons, the imaging targets are often steep dipping faults, causing a lot of diffractions. Without further preprocessing these geological structures are often hidden behind the noise in the data. In this PICO presentation we will present a workflow consisting of data processing steps, which enhance the signal-to-noise ratio, followed by a visualization step based on the use the commercially available general purpose 3D visualization system Avizo. Specifically, we have used Avizo Earth, an extension to Avizo, which supports the import of seismic data in SEG-Y format and offers easy access to state-of-the-art 3D visualization methods at interactive frame rates, even for large seismic data cubes. In seismic interpretation using visualization, interactivity is a key requirement for understanding complex 3D structures. In order to enable an easy communication of the insights gained during the interactive visualization process, animations of the visualized data were created which support the spatial understanding of the data.

Current and Future Critical Issues in Rocket Propulsion Systems

NASA Technical Reports Server (NTRS)

Navaz, Homayun K.; Dix, Jeff C.

1998-01-01

The objective of this research was to tackle several problems that are currently of great importance to NASA. In a liquid rocket engine several complex processes take place that are not thoroughly understood. Droplet evaporation, turbulence, finite rate chemistry, instability, and injection/atomization phenomena are some of the critical issues being encountered in a liquid rocket engine environment. Pulse Detonation Engines (PDE) performance, combustion chamber instability analysis, 60K motor flowfield pattern from hydrocarbon fuel combustion, and 3D flowfield analysis for the Combined Cycle engine were of special interest to NASA. During the summer of 1997, we made an attempt to generate computational results for all of the above problems and shed some light on understanding some of the complex physical phenomena. For this purpose, the Liquid Thrust Chamber Performance (LTCP) code, mainly designed for liquid rocket engine applications, was utilized. The following test cases were considered: (1) Characterization of a detonation wave in a Pulse Detonation Tube; (2) 60K Motor wall temperature studies; (3) Propagation of a pressure pulse in a combustion chamber (under single and two-phase flow conditions); (4) Transonic region flowfield analysis affected by viscous effects; (5) Exploring the viscous differences between a smooth and a corrugated wall; and (6) 3D thrust chamber flowfield analysis of the Combined Cycle engine. It was shown that the LTCP-2D and LTCP-3D codes are capable of solving complex and stiff conservation equations for gaseous and droplet phases in a very robust and efficient manner. These codes can be run on a workstation and personal computers (PC's).

Imaging the 3D flow around swimming Chlamydomonas reinhardtii using digital inline holographic microscopy

NASA Astrophysics Data System (ADS)

Welch, Kyle; Kumar, Santosh; Hong, Jiarong; Cheng, Xiang

2017-11-01

Understanding the 3D flow induced by microswimmers is paramount to revealing how they interact with each other and their environment. While many studies have measured 2D projections of flow fields around single microorganisms, reliable 3D measurement remains elusive due to the difficulty in imaging fast 3D fluid flows at submicron spatial and millisecond temporal scales. Here, we present a precision measurement of the 3D flow field induced by motile planktonic algae cells, Chlamydomonas reinhardtii. We manually capture and hold stationary a single alga using a micropipette, while still allowing it to beat its flagella in the breastroke pattern characteristic to C. reinhardtii. The 3D flow field around the alga is then tracked by employing fast holographic imaging on 1 um tracer particles, which leads to a spatial resolution of 100 nm along the optical axis and 40 nm in the imaging plane normal to the optical axis. We image the flow around a single alga continuously through thousands of flagellar beat cycles and aggregate that data into a complete 3D flow field. Our study demonstrates the power of holography in imaging fast complex microscopic flow structures and provides crucial information for understanding the detailed locomotion of swimming microorganisms.

LivePhantom: Retrieving Virtual World Light Data to Real Environments.

PubMed

Kolivand, Hoshang; Billinghurst, Mark; Sunar, Mohd Shahrizal

2016-01-01

To achieve realistic Augmented Reality (AR), shadows play an important role in creating a 3D impression of a scene. Casting virtual shadows on real and virtual objects is one of the topics of research being conducted in this area. In this paper, we propose a new method for creating complex AR indoor scenes using real time depth detection to exert virtual shadows on virtual and real environments. A Kinect camera was used to produce a depth map for the physical scene mixing into a single real-time transparent tacit surface. Once this is created, the camera's position can be tracked from the reconstructed 3D scene. Real objects are represented by virtual object phantoms in the AR scene enabling users holding a webcam and a standard Kinect camera to capture and reconstruct environments simultaneously. The tracking capability of the algorithm is shown and the findings are assessed drawing upon qualitative and quantitative methods making comparisons with previous AR phantom generation applications. The results demonstrate the robustness of the technique for realistic indoor rendering in AR systems.

LivePhantom: Retrieving Virtual World Light Data to Real Environments

PubMed Central

2016-01-01

To achieve realistic Augmented Reality (AR), shadows play an important role in creating a 3D impression of a scene. Casting virtual shadows on real and virtual objects is one of the topics of research being conducted in this area. In this paper, we propose a new method for creating complex AR indoor scenes using real time depth detection to exert virtual shadows on virtual and real environments. A Kinect camera was used to produce a depth map for the physical scene mixing into a single real-time transparent tacit surface. Once this is created, the camera’s position can be tracked from the reconstructed 3D scene. Real objects are represented by virtual object phantoms in the AR scene enabling users holding a webcam and a standard Kinect camera to capture and reconstruct environments simultaneously. The tracking capability of the algorithm is shown and the findings are assessed drawing upon qualitative and quantitative methods making comparisons with previous AR phantom generation applications. The results demonstrate the robustness of the technique for realistic indoor rendering in AR systems. PMID:27930663

Assembly and property research on seven 0D-3D complexes derived from imidazole dicarboxylate and 1,2-bi(pyridin-4-yl)ethene

NASA Astrophysics Data System (ADS)

Mu, Bao; Li, Qian; Lv, Lei; Yang, Dan-Dan; Wang, Qing; Huang, Ru-Dan

2015-03-01

The hydrothermal reaction of transition metals, 1H-imidazole-4,5-dicarboxylic acid (H3ImDC) and 1,2-bi(pyridin-4-yl)ethene (bpe) affords a series of new complexes, namely, [Mn(HImDC)(bpe)(H2O)] (1), [M(H2ImDC)2(H2O)2]·(bpe) (M=Fe(2), Co(3), Zn(4), Cd(6)), [Zn3(ImDC)2(bpe)(H2O)]·3H2O (5) and [Cd(H2ImDC)(bpe)] (7), which are characterized by elemental analyses, IR, TG, XRPD and single crystal X-ray diffraction. Complex 1 exhibits a one dimensional (1D) zigzag chain with two types of irregular rings, and the 1D chains are linked to form a three dimensional (3D) supramolecular framework by the hydrogen bonding interactions (O-H•••O and O-H•••N). Complexes 2-4 and 6 are isomorphous, and they display the mononuclear structures. In these complexes, the O-H•••O and O-H•••N hydrogen bonds play an important role in sustaining the whole 3D supramolecular frameworks. Complex 5 shows a (3,3)-connected 3D framework with (103) topology, and the lattice water molecules as guest molecules exist in the 3D framework. Complex 7 is a wave-like two dimensional (2D) structure, in which the adjacent 1D chains point at the opposite directions. Moreover, the fluorescent properties of complexes 1-7 and the magnetic property of 1 have been investigated. The water vapor adsorption for complex 5 has been researched at 298 K.

Micro- and nanotechnology in cardiovascular tissue engineering.

PubMed

Zhang, Boyang; Xiao, Yun; Hsieh, Anne; Thavandiran, Nimalan; Radisic, Milica

2011-12-09

While in nature the formation of complex tissues is gradually shaped by the long journey of development, in tissue engineering constructing complex tissues relies heavily on our ability to directly manipulate and control the micro-cellular environment in vitro. Not surprisingly, advancements in both microfabrication and nanofabrication have powered the field of tissue engineering in many aspects. Focusing on cardiac tissue engineering, this paper highlights the applications of fabrication techniques in various aspects of tissue engineering research: (1) cell responses to micro- and nanopatterned topographical cues, (2) cell responses to patterned biochemical cues, (3) controlled 3D scaffolds, (4) patterned tissue vascularization and (5) electromechanical regulation of tissue assembly and function.

Framsticks

NASA Astrophysics Data System (ADS)

Komosinski, Maciej; Ulatowski, Szymon

Life is one of the most complex phenomena known in our world. Researchers construct various models of life that serve diverse purposes and are applied in a wide range of areas — from medicine to entertainment. A part of artificial life research focuses on designing three-dimensional (3D) models of life-forms, which are obviously appealing to observers because the world we live in is three dimensional. Thus, we can easily understand behaviors demonstrated by virtual individuals, study behavioral changes during simulated evolution, analyze dependencies between groups of creatures, and so forth. However, 3D models of life-forms are not only attractive because of their resemblance to the real-world organisms. Simulating 3D agents has practical implications: If the simulation is accurate enough, then real robots can be built based on the simulation, as in [22]. Agents can be designed, tested, and optimized in a virtual environment, and the best ones can be constructed as real robots with embedded control systems. This way artificial intelligence algorithms can be “embodied” in the 3D mechanical constructs.

3D Organotypic Culture Model to Study Components of ERK Signaling.

PubMed

Chioni, Athina-Myrto; Bajwa, Rabia Tayba; Grose, Richard

2017-01-01

Organotypic models are 3D in vitro representations of an in vivo environment. Their complexity can range from an epidermal replica to the establishment of a cancer microenvironment. These models have been used for many years, in an attempt to mimic the structure and function of cells and tissues found inside the body. Methods for developing 3D organotypic models differ according to the tissue of interest and the experimental design. For example, cultures may be grown submerged in culture medium and or at an air-liquid interface. Our group is focusing on an air-liquid interface 3D organotypic model. These cultures are grown on a nylon membrane-covered metal grid with the cells embedded in a Collagen-Matrigel gel. This allows cells to grow in an air-liquid interface to enable diffusion and nourishment from the medium below. Subsequently, the organotypic cultures can be used for immunohistochemical staining of various components of ERK signaling, which is a key player in mediating communication between cells and their microenvironment.

Real-time 3D adaptive filtering for portable imaging systems

NASA Astrophysics Data System (ADS)

Bockenbach, Olivier; Ali, Murtaza; Wainwright, Ian; Nadeski, Mark

2015-03-01

Portable imaging devices have proven valuable for emergency medical services both in the field and hospital environments and are becoming more prevalent in clinical settings where the use of larger imaging machines is impractical. 3D adaptive filtering is one of the most advanced techniques aimed at noise reduction and feature enhancement, but is computationally very demanding and hence often not able to run with sufficient performance on a portable platform. In recent years, advanced multicore DSPs have been introduced that attain high processing performance while maintaining low levels of power dissipation. These processors enable the implementation of complex algorithms like 3D adaptive filtering, improving the image quality of portable medical imaging devices. In this study, the performance of a 3D adaptive filtering algorithm on a digital signal processor (DSP) is investigated. The performance is assessed by filtering a volume of size 512x256x128 voxels sampled at a pace of 10 MVoxels/sec.

The 3D LAOKOON--Visual and Verbal in 3D Online Learning Environments.

ERIC Educational Resources Information Center

Liestol, Gunnar

This paper reports on a project where three-dimensional (3D) online gaming environments were exploited for the purpose of academic communication and learning. 3D gaming environments are media and meaning rich and can provide inexpensive solutions for educational purposes. The experiment with teaching and discussions in this setting, however,…

Effects of Presence, Copresence, and Flow on Learning Outcomes in 3D Learning Spaces

ERIC Educational Resources Information Center

Hassell, Martin D.; Goyal, Sandeep; Limayem, Moez; Boughzala, Imed

2012-01-01

The level of satisfaction and effectiveness of 3D virtual learning environments were examined. Additionally, 3D virtual learning environments were compared with face-to-face learning environments. Students that experienced higher levels of flow and presence also experienced more satisfaction but not necessarily more effectiveness with 3D virtual…

Si-F complexing in aqueous fluids: experimental study and implications for transport of immobile elements

NASA Astrophysics Data System (ADS)

Dolejš, David

2014-05-01

Intepretation of fluid-mineral interaction mechanisms and hydrothermal fluxes requires knowledge of predominant solubility and speciation reactions and their thermodynamic properties. Fluorine represents a hard electron donor, capable of complexing and transporting high-field strength elements, which are traditionally considered to be immobile. Reactions responsible for element mobility have general form MOx + y HF (aq) + x - y H2O = M(OH)2x-yFy (aq), and their extent and transport efficiency relies on hydrogen fluoride activity. In natural fluids, a[HF] is controlled by various fluorination equilibria including neutralization of silicates with consequent formation of silicohydroxyfluoride complexes. Quartz solubility in HF-H2O fluids was experimentally determined at 400-800 oC and 100-200 MPa using rapid-quench cold-seal pressure vessels and the mineral weight-loss method. Quartz solubility significantly increases in the presence of hydrogen fluoride: at 400 oC and 100 MPa, dissolved SiO2 ranges from 0.18 wt. % in pure H2O to 12.2 wt. % at 8.3 wt. % F in the fluid, whereas at 800 oC and 200 MPa it rises from 1.51 wt. % in pure H2O to 15.3 wt. % at 8.0 wt. % F in the fluid. The isobaric solubilities of quartz appear to be temperature-independent, i.e., effects of temperature vs. fluid density on the solubility are counteracting. The experimental data are described by the density model: log m[SiO2] = a + blog ρ + clog m[F] + dT , where a = -1.049 mol kg-1, b = 0.816 mol cm-3, c = 0.802 and d = 1.256 · 10-3 mol kg-1 K-1. Solubility isotherms have similar d(log m[SiO2])/d(log m[F]) slopes over the entire range of conditions indicating that Si(OH)2F2 is the major aqueous species. Several factors promote breakdown of silicohydroxyfluoride complexes and precipitation of silica solute: (i) decreasing temperature and pressure, i.e., fluid ascent and cooling and/or (ii) neutralization and increase in the alkali/H ratio of fluids during alteration reactions or removal of hydrogen halides by fluid boiling. Thermodynamic analysis of mineral equilibria in the system SiO2-Al2O3-FeO-MgO-CaO-Na2O-K2O-H2O-F2O-1 indicates that cryolite, topaz, fluorite and sellaite represent fluoride buffers with decreasing chemical potential of F2O-1 or a[HF], in a sequence from peralkaline to peraluminous silicic, intermediate to progressively Ca-rich mafic and, finally, ultramafic environments. Corresponding a[HF] decrease from 100.2 to 10-1 and from 10-1.6 to 10-3.0 mol kg-1 at 800 and 400 oC, respectively, and 100 MPa. These results imply that: (i) silicohydroxyfluoride and aluminumhydroxyfluoride complexes transport Si and Al in quantities appreciably greater than SiO2 (aq) and aluminate species in peraluminous granite and greisen environments only, and (ii) significant transport (10-100 ppm) of high-field strength (e.g., Ti, Zr) and rare earth elements in aqueous fluids is predicted when formation constants of metal-fluoride complexes exceed 101-2 under hydrothermal conditions. This study concludes that in fluorine-bearing environments the transport of Si and Al remains little affected, but HFSE and REE are largely mobile.

Short-term hypoxic preconditioning promotes prevascularization in 3D bioprinted bone constructs with stromal vascular fraction derived cells† †Electronic supplementary information (ESI) available: qPCR primers and Fig. S1. See DOI: 10.1039/c7ra04372d Click here for additional data file.

PubMed Central

Kuss, Mitchell A.; Harms, Robert; Wu, Shaohua; Wang, Ying; Untrauer, Jason B.; Carlson, Mark A.

2017-01-01

Reconstruction of complex, craniofacial bone defects often requires autogenous vascularized bone grafts, and still remains a challenge today. In order to address this issue, we isolated the stromal vascular fraction (SVF) from adipose tissues and maintained the phenotypes and the growth of endothelial lineage cells within SVF derived cells (SVFC) by incorporating an endothelial cell medium. We 3D bioprinted SVFC within our hydrogel bioinks and conditioned the constructs in either normoxia or hypoxia. We found that short-term hypoxic conditioning promoted vascularization-related gene expression, whereas long-term hypoxia impaired cell viability and vascularization. 3D bioprinted bone constructs composed of polycaprolactone/hydroxyapatite (PCL/HAp) and SVFC-laden hydrogel bioinks were then implanted into athymic mice, after conditioning in normoxic or short-term hypoxic environments, in order to determine the in vitro and in vivo vascularization and osteogenic differentiation of the constructs. Short-term hypoxic conditioning promoted microvessel formation in vitro and in vivo and promoted integration with existing host vasculature, but did not affect osteogenic differentiation of SVFC. These findings demonstrate the benefit of short-term hypoxia and the potential for utilization of SVFC and 3D bioprinting for generating prevascularized 3D bioprinted bone constructs. Furthermore, the ability to custom design complex anatomical shapes has promising applications for the regeneration of both large and small craniofacial bone defects. PMID:28670447

Research of Cemented Paste Backfill in Offshore Environments

NASA Astrophysics Data System (ADS)

Wang, Kun; Yang, Peng; Lyu, Wensheng; Lin, Zhixiang

2018-01-01

To promote comprehensive utilization of mine waste tailings and control ground pressure, filling mine stopes with cement paste backfill (CPB) is becoming the most widely used and applicable method in contemporary underground mining. However, many urgent new problems have arisen during the exploitation in offshore mines owing to the complex geohydrology conditions. A series of rheological, settling and mechanical tests were carried out to study the influences of bittern ions on CPB properties in offshore mining. The results showed that: (1) the bittern ion compositions and concentrations of backfill water sampled in mine filling station were similar to seawater. Backfill water mixed CPB slurry with its higher viscosity coefficient was adverse to pipeline gravity transporting; (2) Bleeding rate of backfill water mixed slurry was lower than that prepared with tap water at each cement-tailings ratio; (3) The UCS values of backfill water mixed samples were higher at early curing ages (3d, 7d) and then became lower after longer curing time at 14d and 28d. Therefore, for mine production practice, the offshore environments can have adverse effects on the pipeline gravity transporting and have positive effects on stope dewatering process and early-age strength growth.

Glycosaminoglycan-Mimetic Signals Direct the Osteo/Chondrogenic Differentiation of Mesenchymal Stem Cells in a Three-Dimensional Peptide Nanofiber Extracellular Matrix Mimetic Environment.

PubMed

Arslan, Elif; Guler, Mustafa O; Tekinay, Ayse B

2016-04-11

Recent efforts in bioactive scaffold development focus strongly on the elucidation of complex cellular responses through the use of synthetic systems. Designing synthetic extracellular matrix (ECM) materials must be based on understanding of cellular behaviors upon interaction with natural and artificial scaffolds. Hence, due to their ability to mimic both the biochemical and mechanical properties of the native tissue environment, supramolecular assemblies of bioactive peptide nanostructures are especially promising for development of bioactive ECM-mimetic scaffolds. In this study, we used glycosaminoglycan (GAG) mimetic peptide nanofiber gel as a three-dimensional (3D) platform to investigate how cell lineage commitment is altered by external factors. We observed that amount of fetal bovine serum (FBS) presented in the cell media had synergistic effects on the ability of GAG-mimetic nanofiber gel to mediate the differentiation of mesenchymal stem cells into osteogenic and chondrogenic lineages. In particular, lower FBS concentration in the culture medium was observed to enhance osteogenic differentiation while higher amount FBS promotes chondrogenic differentiation in tandem with the effects of the GAG-mimetic 3D peptide nanofiber network, even in the absence of externally administered growth factors. We therefore demonstrate that mesenchymal stem cell differentiation can be specifically controlled by the combined influence of growth medium components and a 3D peptide nanofiber environment.

Rotary culture enhances pre-osteoblast aggregation and mineralization.

PubMed

Facer, S R; Zaharias, R S; Andracki, M E; Lafoon, J; Hunter, S K; Schneider, G B

2005-06-01

Three-dimensional environments have been shown to enhance cell aggregation and osteoblast differentiation. Thus, we hypothesized that three-dimensional (3D) growth environments would enhance the mineralization rate of human embryonic palatal mesenchymal (HEPM) pre-osteoblasts. The objective of this study was to investigate the potential use of rotary cell culture systems (RCCS) as a means to enhance the osteogenic potential of pre-osteoblast cells. HEPM cells were cultured in a RCCS to create 3D enviroments. Tissue culture plastic (2D) cultures served as our control. 3D environments promoted three-dimensional aggregate formations. Increased calcium and phosphorus deposition was significantly enhanced three- to 18-fold (P < 0.001) in 3D cultures as compared with 2D environments. 3D cultures mineralized in 1 wk as compared with the 2D cultures, which took 4 wks, a decrease in time of nearly 75%. In conclusion, our studies demonstrated that 3D environments enhanced osteoblast cell aggregation and mineralization.

Informatics in radiology: Intuitive user interface for 3D image manipulation using augmented reality and a smartphone as a remote control.

PubMed

Nakata, Norio; Suzuki, Naoki; Hattori, Asaki; Hirai, Naoya; Miyamoto, Yukio; Fukuda, Kunihiko

2012-01-01

Although widely used as a pointing device on personal computers (PCs), the mouse was originally designed for control of two-dimensional (2D) cursor movement and is not suited to complex three-dimensional (3D) image manipulation. Augmented reality (AR) is a field of computer science that involves combining the physical world and an interactive 3D virtual world; it represents a new 3D user interface (UI) paradigm. A system for 3D and four-dimensional (4D) image manipulation has been developed that uses optical tracking AR integrated with a smartphone remote control. The smartphone is placed in a hard case (jacket) with a 2D printed fiducial marker for AR on the back. It is connected to a conventional PC with an embedded Web camera by means of WiFi. The touch screen UI of the smartphone is then used as a remote control for 3D and 4D image manipulation. Using this system, the radiologist can easily manipulate 3D and 4D images from computed tomography and magnetic resonance imaging in an AR environment with high-quality image resolution. Pilot assessment of this system suggests that radiologists will be able to manipulate 3D and 4D images in the reading room in the near future. Supplemental material available at http://radiographics.rsna.org/lookup/suppl/doi:10.1148/rg.324115086/-/DC1.

DPSC colonization of functionalized 3D textiles.

PubMed

Ortiz, Marine; Rosales-Ibáñez, Raúl; Pozos-Guillén, Amaury; De Bien, Charlotte; Toye, Dominique; Flores, Héctor; Grandfils, Christian

2017-05-01

Fiber scaffolds are attractive materials for mimicking, within a 3D in vitro system, any living environment in which animal cells can adhere and proliferate. In three dimensions, cells have the ability to communicate and organize into complex architectures similar to those found in their natural environments. The aim of this study was to evaluate, in terms of cell reactivity, a new in vitro cell model: dental pulp stem cells (DPSCs) in a 3D polymeric textile. Scaffolds were knitted from polyglycolic acid (PGA) or polydioxanone (PDO) fibers differing in surface roughness. To promote cell adhesion, these hydrophobic fabrics were also functionalized with either chitosan or the peptide arginine-glycine-aspartic acid (RGD). Cell behavior was examined 1, 10, and 21 days post-seeding with a LIVE/DEAD ® Kit. Confocal laser scanning microscopy (CLSM) highlighted the biocompatibility of these materials (cell survival rate: 94% to 100%). Fiber roughness was found to influence cell adhesion and viability significantly and favorably. A clear benefit of polymeric textile functionalization with chitosan or RGD was demonstrated in terms of cell adhesion and viability. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 785-794, 2017. © 2016 Wiley Periodicals, Inc.

3D bio-etching of a complex composite-like embryonic tissue.

PubMed

Hazar, Melis; Kim, Yong Tae; Song, Jiho; LeDuc, Philip R; Davidson, Lance A; Messner, William C

2015-08-21

Morphogenesis involves a complex series of cell signaling, migration and differentiation events that are coordinated as tissues self-assemble during embryonic development. Collective cell movements such as those that occur during morphogenesis have typically been studied in 2D with single layers of cultured cells adhering to rigid substrates such as glass or plastic. In vivo, the intricacies of the 3D microenvironment and complex 3D responses are pivotal in the formation of functional tissues. To study such processes as collective cell movements within 3D multilayered tissues, we developed a microfluidic technique capable of producing complex 3D laminar multicellular structures. We call this technique "3D tissue-etching" because it is analogous to techniques used in the microelectromechanics (MEMS) field where complex 3D structures are built by successively removing material from a monolithic solid through subtractive manufacturing. We use a custom-designed microfluidic control system to deliver a range of tissue etching reagents (detergents, chelators, proteases, etc.) to specific regions of multilayered tissues. These tissues were previously isolated by microsurgical excision from embryos of the African claw-toed frog, Xenopus laevis. The ability to shape the 3D form of multicellular tissues and to control 3D stimulation will have a high impact on tissue engineering and regeneration applications in bioengineering and medicine as well as provide significant improvements in the synthesis of highly complex 3D integrated multicellular biosystems.

Single d-metal atoms on F(s) and F(s+) defects of MgO(001): a theoretical study across the periodic table.

PubMed

Neyman, Konstantin M; Inntam, Chan; Matveev, Alexei V; Nasluzov, Vladimir A; Rösch, Notker

2005-08-24

Single d-metal atoms on oxygen defects F(s) and F(s+) of the MgO(001) surface were studied theoretically. We employed an accurate density functional method combined with cluster models, embedded in an elastic polarizable environment, and we applied two gradient-corrected exchange-correlation functionals. In this way, we quantified how 17 metal atoms from groups 6-11 of the periodic table (Cu, Ag, Au; Ni, Pd, Pt; Co, Rh, Ir; Fe, Ru, Os; Mn, Re; and Cr, Mo, W) interact with terrace sites of MgO. We found bonding with F(s) and F(s+) defects to be in general stronger than that with O2- sites, except for Mn-, Re-, and Fe/F(s) complexes. In M/F(s) systems, electron density is accumulated on the metal center in a notable fashion. The binding energy on both kinds of O defects increases from 3d- to 4d- to 5d-atoms of a given group, at variance with the binding energy trend established earlier for the M/O2- complexes, 4d < 3d < 5d. Regarding the evolution of the binding energy along a period, group 7 atoms are slightly destabilized compared to their group 6 congeners in both the F(s) and F(s+) complexes; for later transition elements, the binding energy increases gradually up to group 10 and finally decreases again in group 11, most strongly on the F(s) site. This trend is governed by the negative charge on the adsorbed atoms. We discuss implications for an experimental detection of metal atoms on oxide supports based on computed core-level energies.

New Technologies for Acquisition and 3-D Visualization of Geophysical and Other Data Types Combined for Enhanced Understandings and Efficiencies of Oil and Gas Operations, Deepwater Gulf of Mexico

NASA Astrophysics Data System (ADS)

Thomson, J. A.; Gee, L. J.; George, T.

2002-12-01

This presentation shows results of a visualization method used to display and analyze multiple data types in a geospatially referenced three-dimensional (3-D) space. The integrated data types include sonar and seismic geophysical data, pipeline and geotechnical engineering data, and 3-D facilities models. Visualization of these data collectively in proper 3-D orientation yields insights and synergistic understandings not previously obtainable. Key technological components of the method are: 1) high-resolution geophysical data obtained using a newly developed autonomous underwater vehicle (AUV), 2) 3-D visualization software that delivers correctly positioned display of multiple data types and full 3-D flight navigation within the data space and 3) a highly immersive visualization environment (HIVE) where multidisciplinary teams can work collaboratively to develop enhanced understandings of geospatially complex data relationships. The initial study focused on an active deepwater development area in the Green Canyon protraction area, Gulf of Mexico. Here several planned production facilities required detailed, integrated data analysis for design and installation purposes. To meet the challenges of tight budgets and short timelines, an innovative new method was developed based on the combination of newly developed technologies. Key benefits of the method include enhanced understanding of geologically complex seabed topography and marine soils yielding safer and more efficient pipeline and facilities siting. Environmental benefits include rapid and precise identification of potential locations of protected deepwater biological communities for avoidance and protection during exploration and production operations. In addition, the method allows data presentation and transfer of learnings to an audience outside the scientific and engineering team. This includes regulatory personnel, marine archaeologists, industry partners and others.

Synthesis, characterization and solid state electrical properties of 1-D coordination polymer of the type [Cu{sub x}Ni{sub 1-x}(dadb){center_dot}yH{sub 2}O]{sub n}

DOE Office of Scientific and Technical Information (OSTI.GOV)

Prasad, R.L., E-mail: rlpjc@yahoo.co.in; Kushwaha, A.; Shrivastava, O.N.

2012-12-15

New heterobimetallic complexes [Cu{sub x}Ni{sub 1-x}(dadb){center_dot}yH{sub 2}O]{sub n} {l_brace}where dadb=2,5-Diamino-3,6-dichloro-1,4-benzoquinone (1); x=1 (2), 0.5 (4), 0.25 (5), 0.125 (6), 0.0625 (7) and 0 (3); y=2; n=degree of polymerization{r_brace} were synthesized and characterized. Heterobimetallic complexes show normal magnetic moments, whereas, monometallic complexes exhibit magnetic moments less than the value due to spin only. Thermo-gravimetric analysis shows that degradation of the ligand dadb moiety is being controlled by the electronic environment of the Cu(II) ions in preference over Ni(II) in heterobimetallic complexes. Existence of the mixed valency/non-integral oxidation states of copper and nickel metal ions in the complex 4 has been attributedmore » from magnetic moment and ESR spectral results. Solid state dc electrical conductivity of all the complexes was investigated. Monometallic complexes were found to be semiconductors, whereas heterobimetallic coordination polymer 4 was found to exhibit metallic behaviour. Existence of mixed valency/ non-integral oxidation state of metal ions seems to be responsible for the metallic behaviour. - Graphical abstract: Contrast to the semiconductor monometallic complexes 2 and 3, the heterobimetallic complex 4 exhibits metallic behaviour attributed to the mixed valency/non-integral oxidation state of the metal ions concluded from magnetic and ESR spectral studies. Highlights: Black-Right-Pointing-Pointer 1-D coordination compounds of the type Cu{sub x}Ni{sub 1-x}(dadb){center_dot}yH{sub 2}O were synthesized and characterized. Black-Right-Pointing-Pointer Thermal degradation of the complexes provides an indication of long range electronic communication between metal to ligand. Black-Right-Pointing-Pointer On inclusion of Ni(II) into 1-D coordination polymer of Cu(II). (a) Cu(II) and Ni(II) ions exhibit non-integral oxidation state. (b) resulting heterobimetallic complex 4 exhibits metallic behaviour at all temperature range of the present study whereas monometallic complexes are semiconductor.« less

Human guidance of mobile robots in complex 3D environments using smart glasses

NASA Astrophysics Data System (ADS)

Kopinsky, Ryan; Sharma, Aneesh; Gupta, Nikhil; Ordonez, Camilo; Collins, Emmanuel; Barber, Daniel

2016-05-01

In order for humans to safely work alongside robots in the field, the human-robot (HR) interface, which enables bi-directional communication between human and robot, should be able to quickly and concisely express the robot's intentions and needs. While the robot operates mostly in autonomous mode, the human should be able to intervene to effectively guide the robot in complex, risky and/or highly uncertain scenarios. Using smart glasses such as Google Glass∗, we seek to develop an HR interface that aids in reducing interaction time and distractions during interaction with the robot.

Coherence-domain imaging with harmonic holography

NASA Astrophysics Data System (ADS)

Pu, Ye; Psaltis, Demetri

2017-08-01

Observing the fast dynamics of specific molecules or targets in three-dimensional (3D) space and time inside a crowded and complex environment, such as living cells or tissues, remain one of the grand open challenges in modern science. Harmonic holography tackle this challenge by combining the 3D imaging capability of holography with the ultrafast, coherent optical contrast offered by second-harmonic radiating imaging probes (SHRIMPs). Similar to fluorescence, the second-harmonic signal emitted from SHRIMPs provides a color contrast against the uninterested background scattering, which can be efficiently suppressed by an optical filter. We review the latest developments in SHRIMPs and harmonic holography and discuss their further applications in fluidics and biofluidics.

Modeling of flow-induced shear stress applied on 3D cellular scaffolds: Implications for vascular tissue engineering.

PubMed

Lesman, Ayelet; Blinder, Yaron; Levenberg, Shulamit

2010-02-15

Novel tissue-culture bioreactors employ flow-induced shear stress as a means of mechanical stimulation of cells. We developed a computational fluid dynamics model of the complex three-dimensional (3D) microstructure of a porous scaffold incubated in a direct perfusion bioreactor. Our model was designed to predict high shear-stress values within the physiological range of those naturally sensed by vascular cells (1-10 dyne/cm(2)), and will thereby provide suitable conditions for vascular tissue-engineering experiments. The model also accounts for cellular growth, which was designed as an added cell layer grown on all scaffold walls. Five model variants were designed, with geometric differences corresponding to cell-layer thicknesses of 0, 50, 75, 100, and 125 microm. Four inlet velocities (0.5, 1, 1.5, and 2 cm/s) were applied to each model. Wall shear-stress distribution and overall pressure drop calculations were then used to characterize the relation between flow rate, shear stress, cell-layer thickness, and pressure drop. The simulations showed that cellular growth within 3D scaffolds exposes cells to elevated shear stress, with considerably increasing average values in correlation to cell growth and inflow velocity. Our results provide in-depth analysis of the microdynamic environment of cells cultured within 3D environments, and thus provide advanced control over tissue development in vitro. 2009 Wiley Periodicals, Inc.

Comparison of Space Shuttle Hot Gas Manifold analysis to air flow data

NASA Technical Reports Server (NTRS)

Mcconnaughey, P. K.

1988-01-01

This paper summarizes several recent analyses of the Space Shuttle Main Engine Hot Gas Manifold and compares predicted flow environments to air flow data. Codes used in these analyses include INS3D, PAGE, PHOENICS, and VAST. Both laminar (Re = 250, M = 0.30) and turbulent (Re = 1.9 million, M = 0.30) results are discussed, with the latter being compared to data for system losses, outer wall static pressures, and manifold exit Mach number profiles. Comparison of predicted results for the turbulent case to air flow data shows that the analysis using INS3D predicted system losses within 1 percent error, while the PHOENICS, PAGE, and VAST codes erred by 31, 35, and 47 percent, respectively. The INS3D, PHOENICS, and PAGE codes did a reasonable job of predicting outer wall static pressure, while the PHOENICS code predicted exit Mach number profiles with acceptable accuracy. INS3D was approximately an order of magnitude more efficient than the other codes in terms of code speed and memory requirements. In general, it is seen that complex internal flows in manifold-like geometries can be predicted with a limited degree of confidence, and further development is necessary to improve both efficiency and accuracy of codes if they are to be used as design tools for complex three-dimensional geometries.

A CROSSED MOLECULAR BEAM, LOW-TEMPERATURE KINETICS, AND THEORETICAL INVESTIGATION OF THE REACTION OF THE CYANO RADICAL (CN) WITH 1,3-BUTADIENE (C{sub 4}H{sub 6}). A ROUTE TO COMPLEX NITROGEN-BEARING MOLECULES IN LOW-TEMPERATURE EXTRATERRESTRIAL ENVIRONMENTS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Morales, Sebastien B.; Bennett, Christopher J.; Le Picard, Sebastien D.

2011-11-20

We present a joint crossed molecular beam and kinetics investigation combined with electronic structure and statistical calculations on the reaction of the ground-state cyano radical, CN(X {sup 2}{Sigma}{sup +}), with the 1,3-butadiene molecule, H{sub 2}CCHCHCH{sub 2}(X {sup 1} A{sub g}), and its partially deuterated counterparts, H{sub 2}CCDCDCH{sub 2}(X {sup 1} A{sub g}) and D{sub 2}CCHCHCD{sub 2}(X {sup 1} A{sub g}). The crossed beam studies indicate that the reaction proceeds via a long-lived C{sub 5}H{sub 6}N complex, yielding C{sub 5}H{sub 5}N isomer(s) plus atomic hydrogen under single collision conditions as the nascent product(s). Experiments with the partially deuterated 1,3-butadienes indicate thatmore » the atomic hydrogen loss originates from one of the terminal carbon atoms of 1,3-butadiene. A combination of the experimental data with electronic structure calculations suggests that the thermodynamically less favorable 1-cyano-1,3-butadiene isomer represents the dominant reaction product; possible minor contributions of less than a few percent from the aromatic pyridine molecule might be feasible. Low-temperature kinetics studies demonstrate that the overall reaction is very fast from room temperature down to 23 K with rate coefficients close to the gas kinetic limit. This finding, combined with theoretical calculations, indicates that the reaction proceeds on an entrance barrier-less potential energy surface (PES). This combined experimental and theoretical approach represents an important step toward a systematic understanding of the formation of complex, nitrogen-bearing molecules-here on the C{sub 5}H{sub 6}N PES-in low-temperature extraterrestrial environments. These results are compared to the reaction dynamics of D1-ethynyl radicals (C{sub 2}D; X {sup 2}{Sigma}{sup +}) with 1,3-butadiene accessing the isoelectronic C{sub 6}H{sub 7} surface as tackled earlier in our laboratories.« less

Microfluidics for Cancer Nanomedicine: From Fabrication to Evaluation.

PubMed

Zhang, Hao; Zhu, Yifeng; Shen, Youqing

2018-05-27

Self-assembled drug delivery systems (sDDSs), made from nanocarriers and drugs, are one of the major types of nanomedicines, many of which are in clinical use, under preclinical investigation, or in clinical trials. One of the hurdles of this type of nanomedicine in real applications is the inherent complexity of their fabrication processes, which generally lack precise control over the sDDS structures and the batch-to-batch reproducibility. Furthermore, the classic 2D in vitro cell model, monolayer cell culture, has been used to evaluate sDDSs. However, 2D cell culture cannot adequately replicate in vivo tissue-level structures and their highly complex dynamic 3D environments, nor can it simulate their functions. Thus, evaluations using 2D cell culture often cannot correctly correlate with sDDS behaviors and effects in humans. Microfluidic technology offers novel solutions to overcome these problems and facilitates studying the structure-performance relationships for sDDS developments. In this Review, recent advances in microfluidics for 1) fabrication of sDDSs with well-defined physicochemical properties, such as size, shape, rigidity, and drug-loading efficiency, and 2) fabrication of 3D-cell cultures as "tissue/organ-on-a-chip" platforms for evaluations of sDDS biological performance are in focus. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

3D laser scanning and modelling of the Dhow heritage for the Qatar National Museum

NASA Astrophysics Data System (ADS)

Wetherelt, A.; Cooper, J. P.; Zazzaro, C.

2014-08-01

Curating boats can be difficult. They are complex structures, often demanding to conserve whether in or out of the water; they are usually large, difficult to move on land, and demanding of gallery space. Communicating life on board to a visiting public in the terra firma context of a museum can be difficult. Boats in their native environment are inherently dynamic artifacts. In a museum they can be static and divorced from the maritime context that might inspire engagement. New technologies offer new approaches to these problems. 3D laser scanning and digital modeling offers museums a multifaceted means of recording, monitoring, studying and communicating watercraft in their care. In this paper we describe the application of 3D laser scanning and subsequent digital modeling. Laser scans were further developed using computer-generated imagery (CGI) modeling techniques to produce photorealistic 3D digital models for development into interactive, media-based museum displays. The scans were also used to generate 2D naval lines and orthographic drawings as a lasting curatorial record of the dhows held by the National Museum of Qatar.

Authoring Adaptive 3D Virtual Learning Environments

ERIC Educational Resources Information Center

Ewais, Ahmed; De Troyer, Olga

2014-01-01

The use of 3D and Virtual Reality is gaining interest in the context of academic discussions on E-learning technologies. However, the use of 3D for learning environments also has drawbacks. One way to overcome these drawbacks is by having an adaptive learning environment, i.e., an environment that dynamically adapts to the learner and the…

Nanoscale tissue engineering: spatial control over cell-materials interactions

PubMed Central

Wheeldon, Ian; Farhadi, Arash; Bick, Alexander G.; Jabbari, Esmaiel; Khademhosseini, Ali

2011-01-01

Cells interact with the surrounding environment by making tens to hundreds of thousands of nanoscale interactions with extracellular signals and features. The goal of nanoscale tissue engineering is to harness the interactions through nanoscale biomaterials engineering in order to study and direct cellular behaviors. Here, we review the nanoscale tissue engineering technologies for both two- and three-dimensional studies (2- and 3D), and provide a holistic overview of the field. Techniques that can control the average spacing and clustering of cell adhesion ligands are well established and have been highly successful in describing cell adhesion and migration in 2D. Extension of these engineering tools to 3D biomaterials has created many new hydrogel and nanofiber scaffolds technologies that are being used to design in vitro experiments with more physiologically relevant conditions. Researchers are beginning to study complex cell functions in 3D, however, there is a need for biomaterials systems that provide fine control over the nanoscale presentation of bioactive ligands in 3D. Additionally, there is a need for 2- and 3D techniques that can control the nanoscale presentation of multiple bioactive ligands and the temporal changes in cellular microenvironment. PMID:21451238

Additive Manufacturing for Affordable Rocket Engines

NASA Technical Reports Server (NTRS)

West, Brian; Robertson, Elizabeth; Osborne, Robin; Calvert, Marty

2016-01-01

Additive manufacturing (also known as 3D printing) technology has the potential to drastically reduce costs and lead times associated with the development of complex liquid rocket engine systems. NASA is using 3D printing to manufacture rocket engine components including augmented spark igniters, injectors, turbopumps, and valves. NASA is advancing the process to certify these components for flight. Success Story: MSFC has been developing rocket 3D-printing technology using the Selective Laser Melting (SLM) process. Over the last several years, NASA has built and tested several injectors and combustion chambers. Recently, MSFC has 3D printed an augmented spark igniter for potential use the RS-25 engines that will be used on the Space Launch System. The new design is expected to reduce the cost of the igniter by a factor of four. MSFC has also 3D printed and tested a liquid hydrogen turbopump for potential use on an Upper Stage Engine. Additive manufacturing of the turbopump resulted in a 45% part count reduction. To understanding how the 3D printed parts perform and to certify them for flight, MSFC built a breadboard liquid rocket engine using additive manufactured components including injectors, turbomachinery, and valves. The liquid rocket engine was tested seven times in 2016 using liquid oxygen and liquid hydrogen. In addition to exposing the hardware to harsh environments, engineers learned to design for the new manufacturing technique, taking advantage of its capabilities and gaining awareness of its limitations. Benefit: The 3D-printing technology promises reduced cost and schedule for rocket engines. Cost is a function of complexity, and the most complicated features provide the largest opportunities for cost reductions. This is especially true where brazes or welds can be eliminated. The drastic reduction in part count achievable with 3D printing creates a waterfall effect that reduces the number of processes and drawings, decreases the amount of touch labor required, and increases reliability. When certification is achieved, NASA missions will be able to realize these benefits.

Stereo vision tracking of multiple objects in complex indoor environments.

PubMed

Marrón-Romera, Marta; García, Juan C; Sotelo, Miguel A; Pizarro, Daniel; Mazo, Manuel; Cañas, José M; Losada, Cristina; Marcos, Alvaro

2010-01-01

This paper presents a novel system capable of solving the problem of tracking multiple targets in a crowded, complex and dynamic indoor environment, like those typical of mobile robot applications. The proposed solution is based on a stereo vision set in the acquisition step and a probabilistic algorithm in the obstacles position estimation process. The system obtains 3D position and speed information related to each object in the robot's environment; then it achieves a classification between building elements (ceiling, walls, columns and so on) and the rest of items in robot surroundings. All objects in robot surroundings, both dynamic and static, are considered to be obstacles but the structure of the environment itself. A combination of a Bayesian algorithm and a deterministic clustering process is used in order to obtain a multimodal representation of speed and position of detected obstacles. Performance of the final system has been tested against state of the art proposals; test results validate the authors' proposal. The designed algorithms and procedures provide a solution to those applications where similar multimodal data structures are found.

Electrostatics Explains the Position-Dependent Effect of G⋅U Wobble Base Pairs on the Affinity of RNA Kissing Complexes.

PubMed

Abi-Ghanem, Josephine; Rabin, Clémence; Porrini, Massimiliano; Dausse, Eric; Toulmé, Jean-Jacques; Gabelica, Valérie

2017-10-06

In the RNA realm, non-Watson-Crick base pairs are abundant and can affect both the RNA 3D structure and its function. Here, we investigated the formation of RNA kissing complexes in which the loop-loop interaction is modulated by non-Watson-Crick pairs. Mass spectrometry, surface plasmon resonance, and UV-melting experiments show that the G⋅U wobble base pair favors kissing complex formation only when placed at specific positions. We tried to rationalize this effect by molecular modeling, including molecular mechanics Poisson-Boltzmann surface area (MMPBSA) thermodynamics calculations and PBSA calculations of the electrostatic potential surfaces. Modeling reveals that the G⋅U stabilization is due to a specific electrostatic environment defined by the base pairs of the entire loop-loop region. The loop is not symmetric, and therefore the identity and position of each base pair matters. Predicting and visualizing the electrostatic environment created by a given sequence can help to design specific kissing complexes with high affinity, for potential therapeutic, nanotechnology or analytical applications. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Development of 3D Atlas of Metalworking Equipment

NASA Astrophysics Data System (ADS)

Yevgenyevna Maslennikova, Olga; Borisovna Nazarova, Olga; Aleksandrovna Chudinova, Yulia

2018-05-01

The paper is dedicated to solving the problem of developing innovative educational systems able to train personnel of complex and dangerous manufacturing industries (such as in metallurgy) to control the process not only under regular conditions, but in emergency and pre-emergency situations as well. At that, such educational systems shall transform training of future and current engineers into a professional activity, model both subject matter and social content of their professional labor. Key characteristics of a 3D atlas of equipment as an educational system are given, as it provides immersion of trainees into professional environment. Requirements for such systems are defined (functional, information, software and technical). Stages of development of a 3D atlas of equipment as an automated system are given, allowing one to get closer to yet another problem that of IT specialist training so that they are able to design, implement and deploy such systems.

Robotic Online Path Planning on Point Cloud.

PubMed

Liu, Ming

2016-05-01

This paper deals with the path-planning problem for mobile wheeled- or tracked-robot which drive in 2.5-D environments, where the traversable surface is usually considered as a 2-D-manifold embedded in a 3-D ambient space. Specially, we aim at solving the 2.5-D navigation problem using raw point cloud as input. The proposed method is independent of traditional surface parametrization or reconstruction methods, such as a meshing process, which generally has high-computational complexity. Instead, we utilize the output of 3-D tensor voting framework on the raw point clouds. The computation of tensor voting is accelerated by optimized implementation on graphics computation unit. Based on the tensor voting results, a novel local Riemannian metric is defined using the saliency components, which helps the modeling of the latent traversable surface. Using the proposed metric, we prove that the geodesic in the 3-D tensor space leads to rational path-planning results by experiments. Compared to traditional methods, the results reveal the advantages of the proposed method in terms of smoothing the robot maneuver while considering the minimum travel distance.

Agent-based model of diffusion of N-acyl homoserine lactones in a multicellular environment of Pseudomonas aeruginosa and Candida albicans.

PubMed

Pérez-Rodríguez, Gael; Dias, Sónia; Pérez-Pérez, Martín; Fdez-Riverola, Florentino; Azevedo, Nuno F; Lourenço, Anália

2018-03-08

Experimental incapacity to track microbe-microbe interactions in structures like biofilms, and the complexity inherent to the mathematical modelling of those interactions, raises the need for feasible, alternative modelling approaches. This work proposes an agent-based representation of the diffusion of N-acyl homoserine lactones (AHL) in a multicellular environment formed by Pseudomonas aeruginosa and Candida albicans. Depending on the spatial location, C. albicans cells were variably exposed to AHLs, an observation that might help explain why phenotypic switching of individual cells in biofilms occurred at different time points. The simulation and algebraic results were similar for simpler scenarios, although some statistical differences could be observed (p < 0.05). The model was also successfully applied to a more complex scenario representing a small multicellular environment containing C. albicans and P. aeruginosa cells encased in a 3-D matrix. Further development of this model may help create a predictive tool to depict biofilm heterogeneity at the single-cell level.

3D abnormal behavior recognition in power generation

NASA Astrophysics Data System (ADS)

Wei, Zhenhua; Li, Xuesen; Su, Jie; Lin, Jie

2011-06-01

So far most research of human behavior recognition focus on simple individual behavior, such as wave, crouch, jump and bend. This paper will focus on abnormal behavior with objects carrying in power generation. Such as using mobile communication device in main control room, taking helmet off during working and lying down in high place. Taking account of the color and shape are fixed, we adopted edge detecting by color tracking to recognize object in worker. This paper introduces a method, which using geometric character of skeleton and its angle to express sequence of three-dimensional human behavior data. Then adopting Semi-join critical step Hidden Markov Model, weighing probability of critical steps' output to reduce the computational complexity. Training model for every behavior, mean while select some skeleton frames from 3D behavior sample to form a critical step set. This set is a bridge linking 2D observation behavior with 3D human joints feature. The 3D reconstruction is not required during the 2D behavior recognition phase. In the beginning of recognition progress, finding the best match for every frame of 2D observed sample in 3D skeleton set. After that, 2D observed skeleton frames sample will be identified as a specifically 3D behavior by behavior-classifier. The effectiveness of the proposed algorithm is demonstrated with experiments in similar power generation environment.

New insights on the spectrophotometric determination of melatonin pKa values and melatonin-βCD inclusion complex formation constant

NASA Astrophysics Data System (ADS)

Zafra-Roldán, A.; Corona-Avendaño, S.; Montes-Sánchez, R.; Palomar-Pardavé, M.; Romero-Romo, M.; Ramírez-Silva, M. T.

2018-02-01

Using UV-Vis spectrophotometry a stability study of melatonin at different pH values was done in aqueous media, finding that at acidic pH melatonin is unstable when interacting with the environment, however it becomes stable protecting it from light and oxygen. From the UV-Vis spectra and SQUAD software, melatonin pKa values, in a completely protected aqueous medium, were estimated as 5.777 ± 0.011 and 10.201 ± 0.024. Using the same techniques, the melatonin and β-cyclodextrin inclusion complex formation constants were assessed at pH 3, 7 and 11.5, giving the values of log β = (3.07 ± 0.06), (2.94 ± 0.01) and (3.07 ± 0.06) M- 1, respectively. From the global acidity formation constants and the complexes' formation constants, the molar fractions were determined for each species of MT and MT - βCD, to build the molar fraction-[βCD]-pH 3D diagram and the molar fraction-pH 2D diagrams, where it was possible to observe the predominance of the MT species with and without βCD. A voltammetric study at pH 3, allowed obtaining a value of log β = (3.15 ± 0.01) M- 1, which corroborates that obtained through UV-Vis spectrophotometry, supporting strongly the rationale behind using simple, straightforward techniques.

3D Printed Reversible Shape Changing Components with Stimuli Responsive Materials

PubMed Central

Mao, Yiqi; Ding, Zhen; Yuan, Chao; Ai, Shigang; Isakov, Michael; Wu, Jiangtao; Wang, Tiejun; Dunn, Martin L.; Qi, H. Jerry

2016-01-01

The creation of reversibly-actuating components that alter their shapes in a controllable manner in response to environmental stimuli is a grand challenge in active materials, structures, and robotics. Here we demonstrate a new reversible shape-changing component design concept enabled by 3D printing two stimuli responsive polymers—shape memory polymers and hydrogels—in prescribed 3D architectures. This approach uses the swelling of a hydrogel as the driving force for the shape change, and the temperature-dependent modulus of a shape memory polymer to regulate the time of such shape change. Controlling the temperature and aqueous environment allows switching between two stable configurations – the structures are relatively stiff and can carry load in each – without any mechanical loading and unloading. Specific shape changing scenarios, e.g., based on bending, or twisting in prescribed directions, are enabled via the controlled interplay between the active materials and the 3D printed architectures. The physical phenomena are complex and nonintuitive, and so to help understand the interplay of geometric, material, and environmental stimuli parameters we develop 3D nonlinear finite element models. Finally, we create several 2D and 3D shape changing components that demonstrate the role of key parameters and illustrate the broad application potential of the proposed approach. PMID:27109063

3D Printed Reversible Shape Changing Components with Stimuli Responsive Materials

NASA Astrophysics Data System (ADS)

Mao, Yiqi; Ding, Zhen; Yuan, Chao; Ai, Shigang; Isakov, Michael; Wu, Jiangtao; Wang, Tiejun; Dunn, Martin L.; Qi, H. Jerry

2016-04-01

The creation of reversibly-actuating components that alter their shapes in a controllable manner in response to environmental stimuli is a grand challenge in active materials, structures, and robotics. Here we demonstrate a new reversible shape-changing component design concept enabled by 3D printing two stimuli responsive polymers—shape memory polymers and hydrogels—in prescribed 3D architectures. This approach uses the swelling of a hydrogel as the driving force for the shape change, and the temperature-dependent modulus of a shape memory polymer to regulate the time of such shape change. Controlling the temperature and aqueous environment allows switching between two stable configurations - the structures are relatively stiff and can carry load in each - without any mechanical loading and unloading. Specific shape changing scenarios, e.g., based on bending, or twisting in prescribed directions, are enabled via the controlled interplay between the active materials and the 3D printed architectures. The physical phenomena are complex and nonintuitive, and so to help understand the interplay of geometric, material, and environmental stimuli parameters we develop 3D nonlinear finite element models. Finally, we create several 2D and 3D shape changing components that demonstrate the role of key parameters and illustrate the broad application potential of the proposed approach.

High Resolution Stratigraphic Mapping in Complex Terrain: A Comparison of Traditional Remote Sensing Techniques with Unmanned Aerial Vehicle - Structure from Motion Photogrammetry

NASA Astrophysics Data System (ADS)

Nesbit, P. R.; Hugenholtz, C.; Durkin, P.; Hubbard, S. M.; Kucharczyk, M.; Barchyn, T.

2016-12-01

Remote sensing and digital mapping have started to revolutionize geologic mapping in recent years as a result of their realized potential to provide high resolution 3D models of outcrops to assist with interpretation, visualization, and obtaining accurate measurements of inaccessible areas. However, in stratigraphic mapping applications in complex terrain, it is difficult to acquire information with sufficient detail at a wide spatial coverage with conventional techniques. We demonstrate the potential of a UAV and Structure from Motion (SfM) photogrammetric approach for improving 3D stratigraphic mapping applications within a complex badland topography. Our case study is performed in Dinosaur Provincial Park (Alberta, Canada), mapping late Cretaceous fluvial meander belt deposits of the Dinosaur Park formation amidst a succession of steeply sloping hills and abundant drainages - creating a challenge for stratigraphic mapping. The UAV-SfM dataset (2 cm spatial resolution) is compared directly with a combined satellite and aerial LiDAR dataset (30 cm spatial resolution) to reveal advantages and limitations of each dataset before presenting a unique workflow that utilizes the dense point cloud from the UAV-SfM dataset for analysis. The UAV-SfM dense point cloud minimizes distortion, preserves 3D structure, and records an RGB attribute - adding potential value in future studies. The proposed UAV-SfM workflow allows for high spatial resolution remote sensing of stratigraphy in complex topographic environments. This extended capability can add value to field observations and has the potential to be integrated with subsurface petroleum models.

Heteroreceptor Complexes Formed by Dopamine D1, Histamine H3, and N-Methyl-D-Aspartate Glutamate Receptors as Targets to Prevent Neuronal Death in Alzheimer's Disease.

PubMed

Rodríguez-Ruiz, Mar; Moreno, Estefanía; Moreno-Delgado, David; Navarro, Gemma; Mallol, Josefa; Cortés, Antonio; Lluís, Carme; Canela, Enric I; Casadó, Vicent; McCormick, Peter J; Franco, Rafael

2017-08-01

Alzheimer's disease (AD) is a neurodegenerative disorder causing progressive memory loss and cognitive dysfunction. Anti-AD strategies targeting cell receptors consider them as isolated units. However, many cell surface receptors cooperate and physically contact each other forming complexes having different biochemical properties than individual receptors. We here report the discovery of dopamine D 1 , histamine H 3 , and N-methyl-D-aspartate (NMDA) glutamate receptor heteromers in heterologous systems and in rodent brain cortex. Heteromers were detected by co-immunoprecipitation and in situ proximity ligation assays (PLA) in the rat cortex where H 3 receptor agonists, via negative cross-talk, and H 3 receptor antagonists, via cross-antagonism, decreased D 1 receptor agonist signaling determined by ERK1/2 or Akt phosphorylation, and counteracted D 1 receptor-mediated excitotoxic cell death. Both D 1 and H 3 receptor antagonists also counteracted NMDA toxicity suggesting a complex interaction between NMDA receptors and D 1 -H 3 receptor heteromer function. Likely due to heteromerization, H 3 receptors act as allosteric regulator for D 1 and NMDA receptors. By bioluminescence resonance energy transfer (BRET), we demonstrated that D 1 or H 3 receptors form heteromers with NR1A/NR2B NMDA receptor subunits. D 1 -H 3 -NMDA receptor complexes were confirmed by BRET combined with fluorescence complementation. The endogenous expression of complexes in mouse cortex was determined by PLA and similar expression was observed in wild-type and APP/PS1 mice. Consistent with allosteric receptor-receptor interactions within the complex, H 3 receptor antagonists reduced NMDA or D 1 receptor-mediated excitotoxic cell death in cortical organotypic cultures. Moreover, H 3 receptor antagonists reverted the toxicity induced by ß 1-42 -amyloid peptide. Thus, histamine H 3 receptors in D 1 -H 3 -NMDA heteroreceptor complexes arise as promising targets to prevent neurodegeneration.

Effect of three bis-pyridyl-bis-amide ligands with various spacers on the structural diversity of new multifunctional cobalt(II) coordination polymers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lin, Hong-Yan; Lu, Huizhe; Le, Mao

2015-03-15

Three new cobalt(II) coordination polymers [Co{sub 2}(1,4-NDC){sub 2}(3-bpye)(H{sub 2}O)] (1), [Co(1,4-NDC)(3-bpfp)(H{sub 2}O)] (2) and [Co(1,4-NDC)(3-bpcb)] (3) [3-bpye=N,N′-bis(3-pyridinecarboxamide)-1,2-ethane, 3-bpfp=bis(3-pyridylformyl)piperazine, 3-bpcb=N,N′-bis(3-pyridinecarboxamide)-1,4-benzene, and 1,4-H{sub 2}NDC=1,4-naphthalenedicarboxylic acid] have been hydrothermally synthesized. The structures of complexes 1–3 have been determined by X-ray single crystal diffraction analyses and further characterized by infrared spectroscopy (IR), powder X-ray diffraction (PXRD) and thermogravimetric analyses (TGA). Complex 1 is a 3D coordination structure with 8-connected (4{sup 20}.6{sup 8}) topology constructed from 3D [Co{sub 2}(1,4-NDC){sub 2}(H{sub 2}O)]{sub n} framework and bidentate 3-bpye ligands. Complex 2 shows 1D “cage+cage”-like chain formed by 1D [Co{sub 2}(1,4-NDC){sub 2}]{sub n} ribbon chains and [Co{sub 2}(3-bpfp){submore » 2}] loops, which are further linked by hydrogen bonding interactions to form a 3D supramolecular network. Complex 3 displays a 3D coordination network with a 6-connected (4{sup 12}.6{sup 3}) topology based on 2D [Co{sub 2}(1,4-NDC){sub 2}]{sub n} layers and bidentate 3-bpcb bridging ligands. The influences of different bis-pyridyl-bis-amide ligands with various spacers on the structures of title complexes are studied. Moreover, the fluorescent properties, electrochemical behaviors and magnetic properties of complexes 1–3 have been investigated. - Graphical abstract: Three multifunctional cobalt(II) complexes constructed from three bis-pyridyl-bis-amide and 1,4-naphthalenedicarboxylic acid have been hydrothermally synthesized and characterized. The fluorescent, electrochemical and magnetic properties of 1–3 have been investigated. - Highlights: • Three multifunctional cobalt(II) complexes based on various bis-pyridyl-bis-amide ligands. • Complex 1 is a 3D coordination structure with 8-connected (4{sup 20}.6{sup 8}) topology. • Complex 2 is a 1D “cage+cage”-like chain. • Complex 3 is a 3D coordination network with a 6-connected (4{sup 12}.6{sup 3}) topology. • The fluorescent, electrochemical and magnetic properties of 1–3 were reported.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gao, X.; Patel, D.J.

The authors report on two-dimensional proton NMR studies of echinomycin complexes with the self-complementary d(A1-C2-G3-Tr) and d(T1-C2-G3-A4) duplexes in aqueous solution. The exchangeable and nonexchangeable antibiotic and nucleic acid protons in the 1 echinomycin per tetranucleotide duplex complexes have been assigned from analyses of scalar coupling and distance connectivities in two-dimensional data sets records in H/sub 2/O and D/sub 2/O solution. An analysis of the intermolecular NOE patterns for both complexes combined with large upfield imino proton and large downfield phosphorus complexation chemical shift changes demonstrates that the two quinoxaline chromophores of echinomycin bisintercalate into the minor groove surrounding themore » dC-dG step of each tetranucleotide duplex. Further, the quinoxaline rings selectively stack between A1 and C2 bases in the d(ACGT) complex and between T1 and C2 bases in the d(TCGA) complex. The intermolecular NOE patterns and the base and sugar proton chemical shifts for residues C2 and G3 are virtually identical for the d(ACGT) and d(TCGA) complexes. A large set of intermolecular contacts established from nuclear Overhauser effects (NOEs) between antibiotic and nucleic acid protons in the echinomycin-tetranucleotide complexes in solution are consistent with corresponding contacts reported for echinomycin-oligonucleotide complexes in the crystalline state. The authors demonstrate that the G x G base pairs adopt Watson-Crick pairing in both d(ACGT) and d(TCGA) complexes in solution. By contrast, the A1 x T4 base pairs adopt Hoogsteen pairing for the echinomycin-d(A1-C2-G3-Tr) complex while the T1 x A4 base pairs adopt Watson-Crick pairing for the echinomycin-d(T1-C2-G3-A4) complex in aqueous solution. These results emphasize the role of sequence in discriminating between Watson-Crick and Hoogsteen pairs at base pairs flanking the echinomycin bisintercalation site in solution.« less

Exploitation of knowledge databases in the synthesis of zinc(II) malonates with photo-sensitive and photo-insensitive N,N'-containing linkers.

PubMed

Zorina-Tikhonova, Ekaterina N; Chistyakov, Aleksandr S; Kiskin, Mikhail A; Sidorov, Aleksei A; Dorovatovskii, Pavel V; Zubavichus, Yan V; Voronova, Eugenia D; Godovikov, Ivan A; Korlyukov, Alexander A; Eremenko, Igor L; Vologzhanina, Anna V

2018-05-01

Photoinitiated solid-state reactions are known to affect the physical properties of coordination polymers, such as fluorescence and sorption behaviour, and also afford extraordinary architectures ( e.g. three-periodic structures with polyorganic ligands). However, the construction of novel photo-sensitive coordination polymers requires an understanding of the factors which govern the mutual disposition of reactive fragments. A series of zinc(II) malonate complexes with 1,2-bis(pyridin-4-yl)ethylene and its photo-insensitive analogues has been synthesized for the purpose of systematic analysis of their underlying nets and mutual disposition of N -donor ligands. The application of a big data-set analysis for the prediction of a variety of possible complex compositions, coordination environments and networks for a four-component system has been demonstrated for the first time. Seven of the nine compounds possess one of the highly probable topologies for their underlying nets; in addition, two novel closely related four-coordinated networks were obtained. Complexes containing 1,2-bis(pyridin-4-yl)ethylene and 1,2-bis(pyridin-4-yl)ethane form isoreticular compounds more readily than those with 4,4'-bipyridine and 1,2-bis(pyridin-4-yl)ethylene. The effects of the precursor, either zinc(II) nitrate or zinc(II) acetate, on the composition and dimensionality of the resulting architecture are discussed. For three of the four novel complexes containing 1,2-bis(pyridin-4-yl)ethylene, the single-crystal-to-single-crystal [2 + 2] cycloaddition reactions were carried out. UV irradiation of these crystals afforded either the 0D→1D or the 3D→3D transformations, with and without network changes. One of the two 3D→3D transformations was accompanied by solvent (H 2 O) cleavage.

3-D Modeling of a Nearshore Dye Release

NASA Astrophysics Data System (ADS)

Maxwell, A. R.; Hibler, L. F.; Miller, L. M.

2006-12-01

The usage of computer modeling software in predicting the behavior of a plume discharged into deep water is well established. Nearfield plume spreading in coastal areas with complex bathymetry is less commonly studied; in addition to geometry, some of the difficulties of this environment include: tidal exchange, temperature, and salinity gradients. Although some researchers have applied complex hydrodynamic models to this problem, nearfield regions are typically modeled by calibration of an empirical or expert system model. In the present study, the 3D hydrodynamic model Delft3D-FLOW was used to predict the advective transport from a point release in Sequim Bay, Washington. A nested model approach was used, wherein a coarse model using a mesh extending to nearby tide gages (cell sizes up to 1 km) was run over several tidal cycles in order to provide boundary conditions to a smaller area. The nested mesh (cell sizes up to 30 m) was forced on two open boundaries using the water surface elevation derived from the coarse model. Initial experiments with the uncalibrated model were conducted in order to predict plume propagation based on the best available field data. Field experiments were subsequently carried out by releasing rhodamine dye into the bay at near-peak flood tidal current and near high slack tidal conditions. Surface and submerged releases were carried out from an anchored vessel. Concurrently collected data from the experiment include temperature, salinity, dye concentration, and hyperspectral imagery, collected from boats and aircraft. A REMUS autonomous underwater vehicle was used to measure current velocity and dye concentration at varying depths, as well as to acquire additional bathymetric information. Preliminary results indicate that the 3D hydrodynamic model offers a reasonable prediction of plume propagation speed and shape. A sensitivity analysis is underway to determine the significant factors in effectively using the model as a predictive tool for plume tracking in data-limited environments. The Delft-PART stochastic particle transport model is also being examined to determine its utility for the present study.

Identification of trapped and boundary lipid binding sites in M13 coat protein/lipid complexes by deuterium NMR spectroscopy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Van Gorkom, L.C.; Horvath, L.I.; Hemminga, M.A.

The major coat protein of M13 bacteriophage has been incorporated into bilayers of 1,2-dimyristoyl-sn-glycero-3-phosphocholine, deuterated in the trimethyl segments of the choline headgroup (DMPC-d9). Two-component deuterium and phosphorus-31 NMR spectra have been observed from bilayer complexes containing the coat protein, indicating slow exchange (on the deuterium quadrupole anisotropy and phosphorus-31 chemical shift averaging time scales) of lipid molecules of less than 10(3) Hz between two motionally distinct environments in the complexes. The fraction of the isotropic spectral component increases with increasing M13 protein concentration, and this component is attributed to lipid headgroups, which are disordered relative to their order inmore » protein-free bilayers. The activation energy of the fast local motions of the trimethyl groups of the choline residue in the headgroup decreases from 23 kJ mol-1 in the pure lipid bilayers to 20 kJ mol-1 for the protein-associated lipid headgroups. The chemical exchange rate of lipid molecules between the two motionally distinct environments has been estimated to be 20-50 Hz by steady-state line-shape simulations of the deuterium spectra of DMPC-d9/M13 coat protein complexes using exchange-coupled modified Bloch equations. The off-rate was, as expected from one-to-one exchange, independent of the L/P ratio; tau off -1 = 0.23 kHz. It is suggested that the protein-associated lipid may be trapped between closely packed parallel aggregates of M13 coat protein and that the high local concentration of protein in a one-dimensional arrangement in lipid bilayers may be required for the fast reassembly of phage particles before release from an infected cell.« less

Three dimensional multi-cellular muscle-like tissue engineering in perfusion-based bioreactors.

PubMed

Cerino, Giulia; Gaudiello, Emanuele; Grussenmeyer, Thomas; Melly, Ludovic; Massai, Diana; Banfi, Andrea; Martin, Ivan; Eckstein, Friedrich; Grapow, Martin; Marsano, Anna

2016-01-01

Conventional tissue engineering strategies often rely on the use of a single progenitor cell source to engineer in vitro biological models; however, multi-cellular environments can better resemble the complexity of native tissues. Previous described co-culture models used skeletal myoblasts, as parenchymal cell source, and mesenchymal or endothelial cells, as stromal component. Here, we propose instead the use of adipose tissue-derived stromal vascular fraction cells, which include both mesenchymal and endothelial cells, to better resemble the native stroma. Percentage of serum supplementation is one of the crucial parameters to steer skeletal myoblasts toward either proliferation (20%) or differentiation (5%) in two-dimensional culture conditions. On the contrary, three-dimensional (3D) skeletal myoblast culture often simply adopts the serum content used in monolayer, without taking into account the new cell environment. When considering 3D cultures of mm-thick engineered tissues, homogeneous and sufficient oxygen supply is paramount to avoid formation of necrotic cores. Perfusion-based bioreactor culture can significantly improve the oxygen access to the cells, enhancing the viability and the contractility of the engineered tissues. In this study, we first investigated the influence of different serum supplementations on the skeletal myoblast ability to proliferate and differentiate during 3D perfusion-based culture. We tested percentages of serum promoting monolayer skeletal myoblast-proliferation (20%) and differentiation (5%) and suitable for stromal cell culture (10%) with a view to identify the most suitable condition for the subsequent co-culture. The 10% serum medium composition resulted in the highest number of mature myotubes and construct functionality. Co-culture with stromal vascular fraction cells at 10% serum also supported the skeletal myoblast differentiation and maturation, hence providing a functional engineered 3D muscle model that resembles the native multi-cellular environment. © 2015 Wiley Periodicals, Inc.

RTEMIS: Real-time Tumoroid and Environment Monitoring Using Impedance Spectroscopy and pH Sensing

NASA Astrophysics Data System (ADS)

Alexander, Frank A., Jr.

This research utilizes Electrical Impedance Spectroscopy, a technique classically used for electrochemical analysis and material characterization, as the basis for a non-destructive, label-free assay platform for three dimensional (3D) cellular spheroids. In this work, a linear array of microelectrodes is optimized to rapidly respond to changes located within a 3D multicellular model. In addition, this technique is coupled with an on chip micro-pH sensor for monitoring the environment around the cells. Finally, the responses of both impedance and pH are correlated with physical changes within the cellular model. The impedance analysis system realized through this work provides a foundation for the development of high-throughput drug screening systems that utilize multiple parallel sensing modalities including pH and impedance sensing in order to quickly assess the efficacy of specific drug candidates. The slow development of new drugs is mainly attributed to poor predictability of current chemosensitivity and resistivity assays, as well as genetic differences between the animal models used for tests and humans. In addition, monolayer cultures used in early experimentation are fundamentally different from the complex structure of organs in vivo. This requires the study of smaller 3D models (spheroids) that more efficiently replicate the conditions within the body. The main objective of this research was to develop a microfluidic system on a chip that is capable of deducing viability and morphology of 3D tumor spheroids by monitoring both the impedance of the cellular model and the pH of their local environment. This would provide a fast and reliable method for screening pharmaceutical compounds in a high-throughput system.

Usability Evaluation of an Adaptive 3D Virtual Learning Environment

ERIC Educational Resources Information Center

Ewais, Ahmed; De Troyer, Olga

2013-01-01

Using 3D virtual environments for educational purposes is becoming attractive because of their rich presentation and interaction capabilities. Furthermore, dynamically adapting the 3D virtual environment to the personal preferences, prior knowledge, skills and competence, learning goals, and the personal or (social) context in which the learning…

Coupled Modeling of Hydrodynamics and Sound in Coastal Ocean for Renewable Ocean Energy Development

DOE Office of Scientific and Technical Information (OSTI.GOV)

Long, Wen; Jung, Ki Won; Yang, Zhaoqing

An underwater sound model was developed to simulate sound propagation from marine and hydrokinetic energy (MHK) devices or offshore wind (OSW) energy platforms. Finite difference methods were developed to solve the 3D Helmholtz equation for sound propagation in the coastal environment. A 3D sparse matrix solver with complex coefficients was formed for solving the resulting acoustic pressure field. The Complex Shifted Laplacian Preconditioner (CSLP) method was applied to solve the matrix system iteratively with MPI parallelization using a high performance cluster. The sound model was then coupled with the Finite Volume Community Ocean Model (FVCOM) for simulating sound propagation generatedmore » by human activities, such as construction of OSW turbines or tidal stream turbine operations, in a range-dependent setting. As a proof of concept, initial validation of the solver is presented for two coastal wedge problems. This sound model can be useful for evaluating impacts on marine mammals due to deployment of MHK devices and OSW energy platforms.« less

Crystal structures of D-tagatose 3-epimerase from Pseudomonas cichorii and its complexes with D-tagatose and D-fructose.

PubMed

Yoshida, Hiromi; Yamada, Mitsugu; Nishitani, Takeyori; Takada, Goro; Izumori, Ken; Kamitori, Shigehiro

2007-11-23

Pseudomonas cichoriiid-tagatose 3-epimerase (P. cichoriid-TE) can efficiently catalyze the epimerization of not only d-tagatose to d-sorbose, but also d-fructose to d-psicose, and is used for the production of d-psicose from d-fructose. The crystal structures of P. cichoriid-TE alone and in complexes with d-tagatose and d-fructose were determined at resolutions of 1.79, 2.28, and 2.06 A, respectively. A subunit of P. cichoriid-TE adopts a (beta/alpha)(8) barrel structure, and a metal ion (Mn(2+)) found in the active site is coordinated by Glu152, Asp185, His211, and Glu246 at the end of the beta-barrel. P. cichoriid-TE forms a stable dimer to give a favorable accessible surface for substrate binding on the front side of the dimer. The simulated omit map indicates that O2 and O3 of d-tagatose and/or d-fructose coordinate Mn(2+), and that C3-O3 is located between carboxyl groups of Glu152 and Glu246, supporting the previously proposed mechanism of deprotonation/protonation at C3 by two Glu residues. Although the electron density is poor at the 4-, 5-, and 6-positions of the substrates, substrate-enzyme interactions can be deduced from the significant electron density at O6. The O6 possibly interacts with Cys66 via hydrogen bonding, whereas O4 and O5 in d-tagatose and O4 in d-fructose do not undergo hydrogen bonding to the enzyme and are in a hydrophobic environment created by Phe7, Trp15, Trp113, and Phe248. Due to the lack of specific interactions between the enzyme and its substrates at the 4- and 5-positions, P. cichoriid-TE loosely recognizes substrates in this region, allowing it to efficiently catalyze the epimerization of d-tagatose and d-fructose (C4 epimer of d-tagatose) as well. Furthermore, a C3-O3 proton-exchange mechanism for P. cichoriid-TE is suggested by X-ray structural analysis, providing a clear explanation for the regulation of the ionization state of Glu152 and Glu246.

Physically-enhanced data visualisation: towards real time solution of Partial Differential Equations in 3D domains

NASA Astrophysics Data System (ADS)

Zlotnik, Sergio

2017-04-01

Information provided by visualisation environments can be largely increased if the data shown is combined with some relevant physical processes and the used is allowed to interact with those processes. This is particularly interesting in VR environments where the user has a deep interplay with the data. For example, a geological seismic line in a 3D "cave" shows information of the geological structure of the subsoil. The available information could be enhanced with the thermal state of the region under study, with water-flow patterns in porous rocks or with rock displacements under some stress conditions. The information added by the physical processes is usually the output of some numerical technique applied to solve a Partial Differential Equation (PDE) that describes the underlying physics. Many techniques are available to obtain numerical solutions of PDE (e.g. Finite Elements, Finite Volumes, Finite Differences, etc). Although, all these traditional techniques require very large computational resources (particularly in 3D), making them useless in a real time visualization environment -such as VR- because the time required to compute a solution is measured in minutes or even in hours. We present here a novel alternative for the resolution of PDE-based problems that is able to provide a 3D solutions for a very large family of problems in real time. That is, the solution is evaluated in a one thousands of a second, making the solver ideal to be embedded into VR environments. Based on Model Order Reduction ideas, the proposed technique divides the computational work in to a computationally intensive "offline" phase, that is run only once in a life time, and an "online" phase that allow the real time evaluation of any solution within a family of problems. Preliminary examples of real time solutions of complex PDE-based problems will be presented, including thermal problems, flow problems, wave problems and some simple coupled problems.

Sensor fusion V; Proceedings of the Meeting, Boston, MA, Nov. 15-17, 1992

NASA Technical Reports Server (NTRS)

Schenker, Paul S. (Editor)

1992-01-01

Topics addressed include 3D object perception, human-machine interface in multisensor systems, sensor fusion architecture, fusion of multiple and distributed sensors, interface and decision models for sensor fusion, computational networks, simple sensing for complex action, multisensor-based control, and metrology and calibration of multisensor systems. Particular attention is given to controlling 3D objects by sketching 2D views, the graphical simulation and animation environment for flexible structure robots, designing robotic systems from sensorimotor modules, cylindrical object reconstruction from a sequence of images, an accurate estimation of surface properties by integrating information using Bayesian networks, an adaptive fusion model for a distributed detection system, multiple concurrent object descriptions in support of autonomous navigation, robot control with multiple sensors and heuristic knowledge, and optical array detectors for image sensors calibration. (No individual items are abstracted in this volume)

Behavior of anionic molybdenum(IV, VI) and tungsten(IV, VI) complexes containing bulky hydrophobic dithiolate ligands and intramolecular NH···S hydrogen bonds in nonpolar solvents.

PubMed

Hasenaka, Yuki; Okamura, Taka-aki; Tatsumi, Miki; Inazumi, Naoya; Onitsuka, Kiyotaka

2014-11-07

Molybdenum(IV, VI) and tungsten(IV, VI) complexes, (Et4N)2[M(IV)O{1,2-S2-3,6-(RCONH)2C6H2}2] and (Et4N)2[M(VI)O2{1,2-S2-3,6-(RCONH)2C6H2}2] (M = Mo, W; R = (4-(t)BuC6H4)3C), with bulky hydrophobic dithiolate ligands containing NH···S hydrogen bonds were synthesized. These complexes are soluble in nonpolar solvents like toluene, which allows the detection of unsymmetrical coordination structures and elusive intermolecular interactions in solution. The (1)H NMR spectra of the complexes in toluene-d8 revealed an unsymmetrical coordination structure, and proximity of the counterions to the anion moiety was suggested at low temperatures. The oxygen-atom-transfer reaction between the molybdenum(IV) complex and Me3NO in toluene was considerably accelerated in nonpolar solvents, and this increase was attributed to the favorable access of the substrate to the active center in the hydrophobic environment.

Effect of strong elastic contrasts on the propagation of seismic wave in hard-rock environments

NASA Astrophysics Data System (ADS)

Saleh, R.; Zheng, L.; Liu, Q.; Milkereit, B.

2013-12-01

Understanding the propagation of seismic waves in a presence of strong elastic contrasts, such as topography, tunnels and ore-bodies is still a challenge. Safety in mining is a major concern and seismic monitoring is the main tool here. For engineering purposes, amplitudes (peak particle velocity/acceleration) and travel times of seismic events (mostly blasts or microseismic events) are critical parameters that have to be determined at various locations in a mine. These parameters are useful in preparing risk maps or to better understand the process of spatial and temporal stress distributions in a mine. Simple constant velocity models used for monitoring studies in mining, cannot explain the observed complexities in scattered seismic waves. In hard-rock environments modeling of elastic seismic wavefield require detailed 3D petrophysical, infrastructure and topographical data to simulate the propagation of seismic wave with a frequencies up to few kilohertz. With the development of efficient numerical techniques, and parallel computation facilities, a solution for such a problem is achievable. In this study, the effects of strong elastic contrasts such as ore-bodies, rough topography and tunnels will be illustrated using 3D modeling method. The main tools here are finite difference code (SOFI3D)[1] that has been benchmarked for engineering studies, and spectral element code (SPECFEM) [2], which was, developed for global seismology problems. The modeling results show locally enhanced peak particle velocity due to presence of strong elastic contrast and topography in models. [1] Bohlen, T. Parallel 3-D viscoelastic finite difference seismic modeling. Computers & Geosciences 28 (2002) 887-899 [2] Komatitsch, D., and J. Tromp, Introduction to the spectral-element method for 3-D seismic wave propagation, Geophys. J. Int., 139, 806-822, 1999.

A method to associate all possible combinations of genetic and environmental factors using GxE landscape plot.

PubMed

Nagaie, Satoshi; Ogishima, Soichi; Nakaya, Jun; Tanaka, Hiroshi

2015-01-01

Genome-wide association studies (GWAS) and linkage analysis has identified many single nucleotide polymorphisms (SNPs) related to disease. There are many unknown SNPs whose minor allele frequencies (MAFs) as low as 0.005 having intermediate effects with odds ratio between 1.5~3.0. Low frequency variants having intermediate effects on disease pathogenesis are believed to have complex interactions with environmental factors called gene-environment interactions (GxE). Hence, we describe a model using 3D Manhattan plot called GxE landscape plot to visualize the association of p-values for gene-environment interactions (GxE). We used the Gene-Environment iNteraction Simulator 2 (GENS2) program to simulate interactions between two genetic loci and one environmental factor in this exercise. The dataset used for training contains disease status, gender, 20 environmental exposures and 100 genotypes for 170 subjects, and p-values were calculated by Cochran-Mantel-Haenszel chi-squared test on known data. Subsequently, we created a 3D GxE landscape plot of negative logarithm of the association of p-values for all the possible combinations of genetic and environmental factors with their hierarchical clustering. Thus, the GxE landscape plot is a valuable model to predict association of p-values for GxE and similarity among genotypes and environments in the context of disease pathogenesis. GxE - Gene-environment interactions, GWAS - Genome-wide association study, MAFs - Minor allele frequencies, SNPs - Single nucleotide polymorphisms, EWAS - Environment-wide association study, FDR - False discovery rate, JPT+CHB - HapMap population of Japanese in Tokyo, Japan - Han Chinese in Beijing.

Capturing tumor complexity in vitro: Comparative analysis of 2D and 3D tumor models for drug discovery.

PubMed

Stock, Kristin; Estrada, Marta F; Vidic, Suzana; Gjerde, Kjersti; Rudisch, Albin; Santo, Vítor E; Barbier, Michaël; Blom, Sami; Arundkar, Sharath C; Selvam, Irwin; Osswald, Annika; Stein, Yan; Gruenewald, Sylvia; Brito, Catarina; van Weerden, Wytske; Rotter, Varda; Boghaert, Erwin; Oren, Moshe; Sommergruber, Wolfgang; Chong, Yolanda; de Hoogt, Ronald; Graeser, Ralph

2016-07-01

Two-dimensional (2D) cell cultures growing on plastic do not recapitulate the three dimensional (3D) architecture and complexity of human tumors. More representative models are required for drug discovery and validation. Here, 2D culture and 3D mono- and stromal co-culture models of increasing complexity have been established and cross-comparisons made using three standard cell carcinoma lines: MCF7, LNCaP, NCI-H1437. Fluorescence-based growth curves, 3D image analysis, immunohistochemistry and treatment responses showed that end points differed according to cell type, stromal co-culture and culture format. The adaptable methodologies described here should guide the choice of appropriate simple and complex in vitro models.

Capturing tumor complexity in vitro: Comparative analysis of 2D and 3D tumor models for drug discovery

PubMed Central

Stock, Kristin; Estrada, Marta F.; Vidic, Suzana; Gjerde, Kjersti; Rudisch, Albin; Santo, Vítor E.; Barbier, Michaël; Blom, Sami; Arundkar, Sharath C.; Selvam, Irwin; Osswald, Annika; Stein, Yan; Gruenewald, Sylvia; Brito, Catarina; van Weerden, Wytske; Rotter, Varda; Boghaert, Erwin; Oren, Moshe; Sommergruber, Wolfgang; Chong, Yolanda; de Hoogt, Ronald; Graeser, Ralph

2016-01-01

Two-dimensional (2D) cell cultures growing on plastic do not recapitulate the three dimensional (3D) architecture and complexity of human tumors. More representative models are required for drug discovery and validation. Here, 2D culture and 3D mono- and stromal co-culture models of increasing complexity have been established and cross-comparisons made using three standard cell carcinoma lines: MCF7, LNCaP, NCI-H1437. Fluorescence-based growth curves, 3D image analysis, immunohistochemistry and treatment responses showed that end points differed according to cell type, stromal co-culture and culture format. The adaptable methodologies described here should guide the choice of appropriate simple and complex in vitro models. PMID:27364600

3D printing of layered brain-like structures using peptide modified gellan gum substrates.

PubMed

Lozano, Rodrigo; Stevens, Leo; Thompson, Brianna C; Gilmore, Kerry J; Gorkin, Robert; Stewart, Elise M; in het Panhuis, Marc; Romero-Ortega, Mario; Wallace, Gordon G

2015-10-01

The brain is an enormously complex organ structured into various regions of layered tissue. Researchers have attempted to study the brain by modeling the architecture using two dimensional (2D) in vitro cell culturing methods. While those platforms attempt to mimic the in vivo environment, they do not truly resemble the three dimensional (3D) microstructure of neuronal tissues. Development of an accurate in vitro model of the brain remains a significant obstacle to our understanding of the functioning of the brain at the tissue or organ level. To address these obstacles, we demonstrate a new method to bioprint 3D brain-like structures consisting of discrete layers of primary neural cells encapsulated in hydrogels. Brain-like structures were constructed using a bio-ink consisting of a novel peptide-modified biopolymer, gellan gum-RGD (RGD-GG), combined with primary cortical neurons. The ink was optimized for a modified reactive printing process and developed for use in traditional cell culturing facilities without the need for extensive bioprinting equipment. Furthermore the peptide modification of the gellan gum hydrogel was found to have a profound positive effect on primary cell proliferation and network formation. The neural cell viability combined with the support of neural network formation demonstrated the cell supportive nature of the matrix. The facile ability to form discrete cell-containing layers validates the application of this novel printing technique to form complex, layered and viable 3D cell structures. These brain-like structures offer the opportunity to reproduce more accurate 3D in vitro microstructures with applications ranging from cell behavior studies to improving our understanding of brain injuries and neurodegenerative diseases. Copyright © 2015 Elsevier Ltd. All rights reserved.

Three-dimensional simulation and auto-stereoscopic 3D display of the battlefield environment based on the particle system algorithm

NASA Astrophysics Data System (ADS)

Ning, Jiwei; Sang, Xinzhu; Xing, Shujun; Cui, Huilong; Yan, Binbin; Yu, Chongxiu; Dou, Wenhua; Xiao, Liquan

2016-10-01

The army's combat training is very important now, and the simulation of the real battlefield environment is of great significance. Two-dimensional information has been unable to meet the demand at present. With the development of virtual reality technology, three-dimensional (3D) simulation of the battlefield environment is possible. In the simulation of 3D battlefield environment, in addition to the terrain, combat personnel and the combat tool ,the simulation of explosions, fire, smoke and other effects is also very important, since these effects can enhance senses of realism and immersion of the 3D scene. However, these special effects are irregular objects, which make it difficult to simulate with the general geometry. Therefore, the simulation of irregular objects is always a hot and difficult research topic in computer graphics. Here, the particle system algorithm is used for simulating irregular objects. We design the simulation of the explosion, fire, smoke based on the particle system and applied it to the battlefield 3D scene. Besides, the battlefield 3D scene simulation with the glasses-free 3D display is carried out with an algorithm based on GPU 4K super-multiview 3D video real-time transformation method. At the same time, with the human-computer interaction function, we ultimately realized glasses-free 3D display of the simulated more realistic and immersed 3D battlefield environment.

Flexible high-resolution display systems for the next generation of radiology reading rooms

NASA Astrophysics Data System (ADS)

Caban, Jesus J.; Wood, Bradford J.; Park, Adrian

2007-03-01

A flexible, scalable, high-resolution display system is presented to support the next generation of radiology reading rooms or interventional radiology suites. The project aims to create an environment for radiologists that will simultaneously facilitate image interpretation, analysis, and understanding while lowering visual and cognitive stress. Displays currently in use present radiologists with technical challenges to exploring complex datasets that we seek to address. These include resolution and brightness, display and ambient lighting differences, and degrees of complexity in addition to side-by-side comparison of time-variant and 2D/3D images. We address these issues through a scalable projector-based system that uses our custom-designed geometrical and photometrical calibration process to create a seamless, bright, high-resolution display environment that can reduce the visual fatigue commonly experienced by radiologists. The system we have designed uses an array of casually aligned projectors to cooperatively increase overall resolution and brightness. Images from a set of projectors in their narrowest zoom are combined at a shared projection surface, thus increasing the global "pixels per inch" (PPI) of the display environment. Two primary challenges - geometric calibration and photometric calibration - remained to be resolved before our high-resolution display system could be used in a radiology reading room or procedure suite. In this paper we present a method that accomplishes those calibrations and creates a flexible high-resolution display environment that appears seamless, sharp, and uniform across different devices.

Agile Integration of Complex Systems

DTIC Science & Technology

2010-04-28

intervention in using SOA can be reduced Page 5 SOA in DoD DoD has mandated that all systems support the Network - Centric Environment and SOA is fundamental to...it and dropping it on an orchestrate icon (slide 22) Di i lifi d d d i l Page 13 scovery s mp e an ma e v sua SOAF Messaging Service Transport

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Yingjie, E-mail: yzx@ansto.gov.au; Karatchevtseva, Inna; Bhadbhade, Mohan

With the coordination of dimethylformamide (DMF), two new uranium(VI) complexes with either 4-hydroxybenzoic acid (H{sub 2}phb) or terephthalic acid (H{sub 2}tph) have been synthesized under solvothermal conditions and structurally characterized. [(UO{sub 2}){sub 2}(Hphb){sub 2}(phb)(DMF)(H{sub 2}O){sub 3}]·4H{sub 2}O (1) has a dinuclear structure constructed with both pentagonal and hexagonal bipyramidal uranium polyhedra linked through a µ{sub 2}-bridging ligand via both chelating carboxylate arm and alcohol oxygen bonding, first observation of such a coordination mode of 4-hydroxybenzoate for 5 f ions. [(UO{sub 2})(tph)(DMF)] (2) has a three-dimensional (3D) framework built with pentagonal bipyramidal uranium polyhedra linked with µ{sub 4}-terephthalate ligands. The 3Dmore » channeled structure is facilitated by the unique carboxylate bonding with nearly linear C–O–U angles and the coordination of DMF molecules. The presence of phb ligands in different coordination modes, uranyl ions in diverse environments and DMF in complex 1, and tph ligand, DMF and uranyl ion in complex 2 has been confirmed by Raman spectroscopy. In addition, their thermal stability and photoluminescence properties have been investigated. - Graphical abstract: With the coordination of dimethylformamide, two new uranyl complexes with either 4-hydroxybenzoate or terephthalate have been synthesized under solvothermal conditions and structurally characterized. - Highlights: • Solvent facilitates the synthesis of two new uranium(VI) complexes. • A dinuclear complex with both penta- and hexagonal bipyramidal uranium polyhedral. • A unique µ{sub 2}-bridging mode of 4-hydroxybenzoate via alcohol oxygen for 5 f ions. • A 3D framework with uranium polyhedra and µ{sub 4}-terephthalate ligands. • Vibration modes and photoluminescence properties are reported.« less

You Can Touch This! Bringing HST images to life as 3-D models

NASA Astrophysics Data System (ADS)

Christian, Carol A.; Nota, A.; Grice, N. A.; Sabbi, E.; Shaheen, N.; Greenfield, P.; Hurst, A.; Kane, S.; Rao, R.; Dutterer, J.; de Mink, S. E.

2014-01-01

We present the very first results of an innovative process to transform Hubble images into tactile 3-D models of astronomical objects. We have created a very new, unique tool for understanding astronomical phenomena, especially designed to make astronomy accessible to visually impaired children and adults. From the multicolor images of stellar clusters, we construct 3-D computer models that are digitally sliced into layers, each featuring touchable patterning and Braille characters, and are printed on a 3-D printer. The slices are then fitted together, so that the user can explore the structure of the cluster environment with their fingertips, slice-by-slice, analogous to a visual fly-through. Students will be able to identify and spatially locate the different components of these complex astronomical objects, namely gas, dust and stars, and will learn about the formation and composition of stellar clusters. The primary audiences for the 3D models are middle school and high school blind students and, secondarily, blind adults. However, we believe that the final materials will address a broad range of individuals with varied and multi-sensory learning styles, and will be interesting and visually appealing to the public at large.

Advanced Fabrication Techniques for Precisely Controlled Micro and Nano Scale Environments for Complex Tissue Regeneration and Biomedical Applications

NASA Astrophysics Data System (ADS)

Holmes, Benjamin

As modern medicine advances, it is still very challenging to cure joint defects due to their poor inherent regenerative capacity, complex stratified architecture, and disparate biomechanical properties. The current clinical standard for catastrophic or late stage joint degradation is a total joint implant, where the damaged joint is completely excised and replaced with a metallic or artificial joint. However, these procedures still only lasts for 10-15 years, and there are hosts of recovery complications which can occur. Thus, these studies have sought to employ advanced biomaterials and scaffold fabricated techniques to effectively regrow joint tissue, instead of merely replacing it with artificial materials. We can hypothesize here that the inclusion of biomimetic and bioactive nanomaterials with highly functional electrospun and 3D printed scaffold can improve physical characteristics (mechanical strength, surface interactions and nanotexture) enhance cellular growth and direct stem cell differentiation for bone, cartilage and vascular growth as well as cancer metastasis modeling. Nanomaterial inclusion and controlled 3D printed features effectively increased nano surface roughness, Young's Modulus and provided effective flow paths for simulated arterial blood. All of the approaches explored proved highly effective for increasing cell growth, as a result of increasing micro-complexity and nanomaterial incorporation. Additionally, chondrogenic and osteogenic differentiation, cell migration, cell to cell interaction and vascular formation were enhanced. Finally, growth-factor(gf)-loaded polymer nanospheres greatly improved vascular cell behavior, and provided a highly bioactive scaffold for mesenchymal stem cell (MSC) and human umbilical vein endothelial cell (HUVEC) co-culture and bone formation. In conclusion, electrospinning and 3D printing when combined effectively with biomimetic and bioactive nanomaterials (i.e. carbon nanomaterials, collagen, nHA, polymer drug delivery nanospheres) can provide high performance, functional materials that also serve as effective tissue forming 3D environments. Both general science knowledge and the translational potential of tissue engineered constructs were advanced by original contributions to the fields for tissue engineering and orthopedic medicine. The most original advancement of general science comes from a successful combination of advanced nanomaterials and biomaterials with existing 3D printing and CAD design to support multiple types of cells and tissues. Future translation of these technologies was advanced due to the highly functional nature of these constructs (i.e. mechanical and hydrodynamic characteristics). Future work would involve more evaluation of vascular neogenesis, small animal models to evaluate bioactivity and biocompatibility and large clinically relevant animals to measure gross tissue formation and biomechanical performance.

Three-dimensional GIS approach for management of assets

NASA Astrophysics Data System (ADS)

Lee, S. Y.; Yee, S. X.; Majid, Z.; Setan, H.

2014-02-01

Assets play an important role in human life, especially to an organization. Organizations strive and put more effort to improve its operation and assets management. The development of GIS technology has become a powerful tool in management as it is able to provide a complete inventory for managing assets with location-based information. Spatial information is one of the requirements in decision making in various areas, including asset management in the buildings. This paper describes a 3D GIS approach for management of assets. An asset management system was developed by integrating GIS concept and 3D model assets. The purposes of 3D visualization to manage assets are to facilitate the analysis and understanding in the complex environment. Behind the 3D model of assets is a database to store the asset information. A user-friendly interface was also designed for more easier to operate the application. In the application developed, location of each individual asset can be easily tracked according to the referring spatial information and 3D viewing. The 3D GIS approach described in this paper is certainly would be useful in asset management. Systematic management of assets can be carried out and this will lead to less-time consuming and cost-effective. The results in this paper will show a new approach to improve asset management.

Modulation of cortical activity in 2D versus 3D virtual reality environments: an EEG study.

PubMed

Slobounov, Semyon M; Ray, William; Johnson, Brian; Slobounov, Elena; Newell, Karl M

2015-03-01

There is a growing empirical evidence that virtual reality (VR) is valuable for education, training, entertaining and medical rehabilitation due to its capacity to represent real-life events and situations. However, the neural mechanisms underlying behavioral confounds in VR environments are still poorly understood. In two experiments, we examined the effect of fully immersive 3D stereoscopic presentations and less immersive 2D VR environments on brain functions and behavioral outcomes. In Experiment 1 we examined behavioral and neural underpinnings of spatial navigation tasks using electroencephalography (EEG). In Experiment 2, we examined EEG correlates of postural stability and balance. Our major findings showed that fully immersive 3D VR induced a higher subjective sense of presence along with enhanced success rate of spatial navigation compared to 2D. In Experiment 1 power of frontal midline EEG (FM-theta) was significantly higher during the encoding phase of route presentation in the 3D VR. In Experiment 2, the 3D VR resulted in greater postural instability and modulation of EEG patterns as a function of 3D versus 2D environments. The findings support the inference that the fully immersive 3D enriched-environment requires allocation of more brain and sensory resources for cognitive/motor control during both tasks than 2D presentations. This is further evidence that 3D VR tasks using EEG may be a promising approach for performance enhancement and potential applications in clinical/rehabilitation settings. Copyright © 2014 Elsevier B.V. All rights reserved.

Halochromism, ionochromism, solvatochromism and density functional study of a synthesized copper(II) complex containing hemilabile amide derivative ligand.

PubMed

Golchoubian, Hamid; Moayyedi, Golasa; Reisi, Neda

2015-03-05

This study investigates chromotropism of newly synthesized 3,3'-(ethane-1,2-diylbis(benzylazanediyl))dipropanamide copper(II) perchlorate complex. The compound was structurally characterized by physico-chemical and spectroscopic methods. X-ray crystallography of the complex showed that the copper atom achieved a distorted square pyramidal environment through coordination of two amine N atoms and two O atoms of the amide moieties. The pH effect on the visible absorption spectrum of the complex was studied which functions as pH-induced "off-on-off" switches through protonation and deprotonation of amide moieties along with the CuO to CuN bond rearrangement at room temperature. The complex was also observed to show solvatochromism and ionochromism. The distinct solution color changes mainly associated with hemilability of the amide groups. The solvatochromism of the complex was investigated with different solvent parameter models using stepwise multiple linear regression method. The results suggested that the basicity power of the solvent has a dominant contribution to the shift of the d-d absorption band of the complex. Density functional theory, DFT calculations were performed in order to study the electronic structure of the complex, the relative stabilities of the CuN/CuO isomers, and to understand the nature of the halochromism processes taking place. DFT computational results buttressed the experimental observations indicating that in the natural pH (5.8) the CuO isomer is more stable than its linkage isomer and conversely in alkaline aqueous solution. Copyright © 2014 Elsevier B.V. All rights reserved.

Towards a Normalised 3D Geovisualisation: The Viewpoint Management

NASA Astrophysics Data System (ADS)

Neuville, R.; Poux, F.; Hallot, P.; Billen, R.

2016-10-01

This paper deals with the viewpoint management in 3D environments considering an allocentric environment. The recent advances in computer sciences and the growing number of affordable remote sensors lead to impressive improvements in the 3D visualisation. Despite some research relating to the analysis of visual variables used in 3D environments, we notice that it lacks a real standardisation of 3D representation rules. In this paper we study the "viewpoint" as being the first considered parameter for a normalised visualisation of 3D data. Unlike in a 2D environment, the viewing direction is not only fixed in a top down direction in 3D. A non-optimal camera location means a poor 3D representation in terms of relayed information. Based on this statement we propose a model based on the analysis of the computational display pixels that determines a viewpoint maximising the relayed information according to one kind of query. We developed an OpenGL prototype working on screen pixels that allows to determine the optimal camera location based on a screen pixels colour algorithm. The viewpoint management constitutes a first step towards a normalised 3D geovisualisation.

Game controller modification for fMRI hyperscanning experiments in a cooperative virtual reality environment.

PubMed

Trees, Jason; Snider, Joseph; Falahpour, Maryam; Guo, Nick; Lu, Kun; Johnson, Douglas C; Poizner, Howard; Liu, Thomas T

2014-01-01

Hyperscanning, an emerging technique in which data from multiple interacting subjects' brains are simultaneously recorded, has become an increasingly popular way to address complex topics, such as "theory of mind." However, most previous fMRI hyperscanning experiments have been limited to abstract social interactions (e.g. phone conversations). Our new method utilizes a virtual reality (VR) environment used for military training, Virtual Battlespace 2 (VBS2), to create realistic avatar-avatar interactions and cooperative tasks. To control the virtual avatar, subjects use a MRI compatible Playstation 3 game controller, modified by removing all extraneous metal components and replacing any necessary ones with 3D printed plastic models. Control of both scanners' operation is initiated by a VBS2 plugin to sync scanner time to the known time within the VR environment. Our modifications include:•Modification of game controller to be MRI compatible.•Design of VBS2 virtual environment for cooperative interactions.•Syncing two MRI machines for simultaneous recording.

Game controller modification for fMRI hyperscanning experiments in a cooperative virtual reality environment

PubMed Central

Trees, Jason; Snider, Joseph; Falahpour, Maryam; Guo, Nick; Lu, Kun; Johnson, Douglas C.; Poizner, Howard; Liu, Thomas T.

2014-01-01

Hyperscanning, an emerging technique in which data from multiple interacting subjects’ brains are simultaneously recorded, has become an increasingly popular way to address complex topics, such as “theory of mind.” However, most previous fMRI hyperscanning experiments have been limited to abstract social interactions (e.g. phone conversations). Our new method utilizes a virtual reality (VR) environment used for military training, Virtual Battlespace 2 (VBS2), to create realistic avatar-avatar interactions and cooperative tasks. To control the virtual avatar, subjects use a MRI compatible Playstation 3 game controller, modified by removing all extraneous metal components and replacing any necessary ones with 3D printed plastic models. Control of both scanners’ operation is initiated by a VBS2 plugin to sync scanner time to the known time within the VR environment. Our modifications include:•Modification of game controller to be MRI compatible.•Design of VBS2 virtual environment for cooperative interactions.•Syncing two MRI machines for simultaneous recording. PMID:26150964

Four coordination polymers based on 5-tert-butyl isophthalic acid and rigid bis(imidazol-1yl)benzene linkers: Synthesis, luminescence detection of acetone and optical properties

DOE Office of Scientific and Technical Information (OSTI.GOV)

Arıcı, Mürsel, E-mail: marici@ogu.edu.tr; Zafer Yeşilel, Okan; Büyükgüngör, Orhan

Four coordination polymers including, [Co(µ-Htbip){sub 2}(µ-dib)]{sub n} (1), [Co(µ-tbip)(µ-dmib){sub 0.5}]{sub n} (2), [Zn{sub 2}(µ-tbip)(µ{sub 3}-tbip)(µ-dmib){sub 1.5}]{sub n} (3) and [Cd(µ{sub 3}-tbip)(µ-dib){sub 0.5} (H{sub 2}O)]{sub n} (4) (tbip: 5-tert-butylisophthalate, dib: 1,4-bis(imidazol-1yl)benzene, dmib: 1,4-bis(imidazol-1yl)-2,5-dimethylbenzene), were hydrothermally synthesized and characterized by elemental analysis, IR spectra, single crystal and powder X-ray diffraction and thermal analysis (TG/DTA). The structural diversity is observed depending on ligands and coordination number of metal centers in the synthesized complexes. The tbip ligand displayed five different coordination modes in its complexes. In 1 and 2, complex 1 is 3D framework with the dia topology while complex 2 has 2D structuremore » with the sql topology depending on coordination geometries of Co ions. Complex 3 is 3D framework with the fsh 4,6-conn topology and complex 4 has 2D 4-connected sql topology. Photoluminescent properties of complex 3 dispersed in various organic solvents were investigated and the results showed that 3 dispersed in methanol could be used as a fluorescent sensor for the detection of acetone. Moreover, thermal and optical properties of the complexes were also studied. - Graphical abstract: Four coordination polymers were hydrothermally synthesized and characterized by various techniques. The complexes showed the structural diversity depending on ligands and coordination number of metal centers. The tbip ligand displayed four different coordination modes in its complexes. In 1 and 2, complexes 1 and 2 are 3D and 2D structures with the dia and sql topologies depending on coordination geometries of Co ions, respectively. Complexes 3 and 4 are 3D and 2D structures with the fsh 4,6-conn and sql topology, respectively. Photoluminescent properties of complex 3 dispersed in various organic solvents were investigated and the results showed that 3 dispersed in methanol could be used as a fluorescent sensor for the detection of acetone. Moreover, thermal and optical properties of the complexes were also studied. - Highlights: • Four new 2D and 3D coordination polymers with 5-tert-butyl isophthalic acid and rigid bis(imidazol-1yl)benzene linkers. • The structural diversity depending on ligands and coordination number of metal centers. • Fluorescent sensor for the detection of acetone.« less

Investigating the capabilities of semantic enrichment of 3D CityEngine data

NASA Astrophysics Data System (ADS)

Solou, Dimitra; Dimopoulou, Efi

2016-08-01

In recent years the development of technology and the lifting of several technical limitations, has brought the third dimension to the fore. The complexity of urban environments and the strong need for land administration, intensify the need of using a three-dimensional cadastral system. Despite the progress in the field of geographic information systems and 3D modeling techniques, there is no fully digital 3D cadastre. The existing geographic information systems and the different methods of three-dimensional modeling allow for better management, visualization and dissemination of information. Nevertheless, these opportunities cannot be totally exploited because of deficiencies in standardization and interoperability in these systems. Within this context, CityGML was developed as an international standard of the Open Geospatial Consortium (OGC) for 3D city models' representation and exchange. CityGML defines geometry and topology for city modeling, also focusing on semantic aspects of 3D city information. The scope of CityGML is to reach common terminology, also addressing the imperative need for interoperability and data integration, taking into account the number of available geographic information systems and modeling techniques. The aim of this paper is to develop an application for managing semantic information of a model generated based on procedural modeling. The model was initially implemented in CityEngine ESRI's software, and then imported to ArcGIS environment. Final goal was the original model's semantic enrichment and then its conversion to CityGML format. Semantic information management and interoperability seemed to be feasible by the use of the 3DCities Project ESRI tools, since its database structure ensures adding semantic information to the CityEngine model and therefore automatically convert to CityGML for advanced analysis and visualization in different application areas.

A novel underwater dam crack detection and classification approach based on sonar images

PubMed Central

Shi, Pengfei; Fan, Xinnan; Ni, Jianjun; Khan, Zubair; Li, Min

2017-01-01

Underwater dam crack detection and classification based on sonar images is a challenging task because underwater environments are complex and because cracks are quite random and diverse in nature. Furthermore, obtainable sonar images are of low resolution. To address these problems, a novel underwater dam crack detection and classification approach based on sonar imagery is proposed. First, the sonar images are divided into image blocks. Second, a clustering analysis of a 3-D feature space is used to obtain the crack fragments. Third, the crack fragments are connected using an improved tensor voting method. Fourth, a minimum spanning tree is used to obtain the crack curve. Finally, an improved evidence theory combined with fuzzy rule reasoning is proposed to classify the cracks. Experimental results show that the proposed approach is able to detect underwater dam cracks and classify them accurately and effectively under complex underwater environments. PMID:28640925

A novel underwater dam crack detection and classification approach based on sonar images.

PubMed

Shi, Pengfei; Fan, Xinnan; Ni, Jianjun; Khan, Zubair; Li, Min

2017-01-01

Underwater dam crack detection and classification based on sonar images is a challenging task because underwater environments are complex and because cracks are quite random and diverse in nature. Furthermore, obtainable sonar images are of low resolution. To address these problems, a novel underwater dam crack detection and classification approach based on sonar imagery is proposed. First, the sonar images are divided into image blocks. Second, a clustering analysis of a 3-D feature space is used to obtain the crack fragments. Third, the crack fragments are connected using an improved tensor voting method. Fourth, a minimum spanning tree is used to obtain the crack curve. Finally, an improved evidence theory combined with fuzzy rule reasoning is proposed to classify the cracks. Experimental results show that the proposed approach is able to detect underwater dam cracks and classify them accurately and effectively under complex underwater environments.

Synthesis of Pyridine– and Pyrazine–BF 3 Complexes and Their Characterization in Solution and Solid State

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chénard, Etienne; Sutrisno, Andre; Zhu, Lingyang

2016-03-31

Following the discovery of the redox-active 1,4- bis-BF 3-quinoxaline complex, we undertook a structure- activity study with the objective to understand the active nature of the quinoxaline complex. Through systematic synthesis and characterization, we have compared complexes prepared from pyridine and pyrazine derivatives, as heterocyclic core analogues. This paper reports the structural requirements that give rise to the electrochemical features of the 1,4-bis-BF 3-quinoxaline adduct. Using solution and solidstate NMR spectroscopy, the role of aromatic ring fusion and nitrogen incorporation in bonding and electronics was elucidated. We establish the boron atom location and its interaction with its environment from 1Dmore » and 2D solution NMR, X-ray diffraction analysis, and 11B solid-state NMR experiments. Crystallographic analysis of single crystals helped to correlate the boron geometry with 11B quadrupolar coupling constant (CQ) and asymmetry parameter (ηQ), extracted from 11B solid-state NMR spectra. Additionally, computations based on density functional theory were performed to predict electrochemical behavior of the BF 3-heteroaromatic complexes. We then experimentally measured electrochemical potential using cyclic voltammetry and found that the redox potentials and CQ values are similarly affected by electronic changes in the complexes.« less

Functionalization of 3D scaffolds with protein-releasing biomaterials for intracellular delivery.

PubMed

Seras-Franzoso, Joaquin; Steurer, Christoph; Roldán, Mònica; Vendrell, Meritxell; Vidaurre-Agut, Carla; Tarruella, Anna; Saldaña, Laura; Vilaboa, Nuria; Parera, Marc; Elizondo, Elisa; Ratera, Imma; Ventosa, Nora; Veciana, Jaume; Campillo-Fernández, Alberto J; García-Fruitós, Elena; Vázquez, Esther; Villaverde, Antonio

2013-10-10

Appropriate combinations of mechanical and biological stimuli are required to promote proper colonization of substrate materials in regenerative medicine. In this context, 3D scaffolds formed by compatible and biodegradable materials are under continuous development in an attempt to mimic the extracellular environment of mammalian cells. We have here explored how novel 3D porous scaffolds constructed by polylactic acid, polycaprolactone or chitosan can be decorated with bacterial inclusion bodies, submicron protein particles formed by releasable functional proteins. A simple dipping-based decoration method tested here specifically favors the penetration of the functional particles deeper than 300μm from the materials' surface. The functionalized surfaces support the intracellular delivery of biologically active proteins to up to more than 80% of the colonizing cells, a process that is slightly influenced by the chemical nature of the scaffold. The combination of 3D soft scaffolds and protein-based sustained release systems (Bioscaffolds) offers promise in the fabrication of bio-inspired hybrid matrices for multifactorial control of cell proliferation in tissue engineering under complex architectonic setting-ups. © 2013.

Desktop-VR system for preflight 3D navigation training

NASA Astrophysics Data System (ADS)

Aoki, Hirofumi; Oman, Charles M.; Buckland, Daniel A.; Natapoff, Alan

Crews who inhabit spacecraft with complex 3D architecture frequently report inflight disorientation and navigation problems. Preflight virtual reality (VR) training may reduce those risks. Although immersive VR techniques may better support spatial orientation training in a local environment, a non-immersive desktop (DT) system may be more convenient for navigation training in "building scale" spaces, especially if the two methods achieve comparable results. In this study trainees' orientation and navigation performance during simulated space station emergency egress tasks was compared while using immersive head-mounted display (HMD) and DT-VR systems. Analyses showed no differences in pointing angular-error or egress time among the groups. The HMD group was significantly faster than DT group when pointing from destination to start location and from start toward different destination. However, this may be attributed to differences in the input device used (a head-tracker for HMD group vs. a keyboard touchpad or a gamepad in the DT group). All other 3D navigation performance measures were similar using the immersive and non-immersive VR systems, suggesting that the simpler desktop VR system may be useful for astronaut 3D navigation training.

Molecular Dynamics Visualization (MDV): Stereoscopic 3D Display of Biomolecular Structure and Interactions Using the Unity Game Engine.

PubMed

Wiebrands, Michael; Malajczuk, Chris J; Woods, Andrew J; Rohl, Andrew L; Mancera, Ricardo L

2018-06-21

Molecular graphics systems are visualization tools which, upon integration into a 3D immersive environment, provide a unique virtual reality experience for research and teaching of biomolecular structure, function and interactions. We have developed a molecular structure and dynamics application, the Molecular Dynamics Visualization tool, that uses the Unity game engine combined with large scale, multi-user, stereoscopic visualization systems to deliver an immersive display experience, particularly with a large cylindrical projection display. The application is structured to separate the biomolecular modeling and visualization systems. The biomolecular model loading and analysis system was developed as a stand-alone C# library and provides the foundation for the custom visualization system built in Unity. All visual models displayed within the tool are generated using Unity-based procedural mesh building routines. A 3D user interface was built to allow seamless dynamic interaction with the model while being viewed in 3D space. Biomolecular structure analysis and display capabilities are exemplified with a range of complex systems involving cell membranes, protein folding and lipid droplets.

USM3D Unstructured Grid Solutions for CAWAPI at NASA LaRC

NASA Technical Reports Server (NTRS)

Lamar, John E.; Abdol-Hamid, Khaled S.

2007-01-01

In support the Cranked Arrow Wing Aerodynamic Project International (CAWAPI) to improve the Technology Readiness Level of flow solvers by comparing results with measured F-16XL-1 flight data, NASA Langley employed the TetrUSS unstructured grid solver, USM3D, to obtain solutions for all seven flight conditions of interest. A newly available solver version that incorporates a number of turbulence models, including the two-equation linear and non-linear k-epsilon, was used in this study. As a first test, a choice was made to utilize only a single grid resolution with the solver for the simulation of the different flight conditions. Comparisons are presented with three turbulence models in USM3D, flight data for surface pressure, boundary-layer profiles, and skin-friction results, as well as limited predictions from other solvers. A result of these comparisons is that the USM3D solver can be used in an engineering environment to predict flow physics on a complex configuration at flight Reynolds numbers with a two-equation linear k-epsilon turbulence model.

Three-Dimensional ZnO Hierarchical Nanostructures: Solution Phase Synthesis and Applications

PubMed Central

Wang, Xiaoliang; Ahmad, Mashkoor

2017-01-01

Zinc oxide (ZnO) nanostructures have been studied extensively in the past 20 years due to their novel electronic, photonic, mechanical and electrochemical properties. Recently, more attention has been paid to assemble nanoscale building blocks into three-dimensional (3D) complex hierarchical structures, which not only inherit the excellent properties of the single building blocks but also provide potential applications in the bottom-up fabrication of functional devices. This review article focuses on 3D ZnO hierarchical nanostructures, and summarizes major advances in the solution phase synthesis, applications in environment, and electrical/electrochemical devices. We present the principles and growth mechanisms of ZnO nanostructures via different solution methods, with an emphasis on rational control of the morphology and assembly. We then discuss the applications of 3D ZnO hierarchical nanostructures in photocatalysis, field emission, electrochemical sensor, and lithium ion batteries. Throughout the discussion, the relationship between the device performance and the microstructures of 3D ZnO hierarchical nanostructures will be highlighted. This review concludes with a personal perspective on the current challenges and future research. PMID:29137195

Developing a 3D Road Cadastral System: Comparing Legal Requirements and User Needs

NASA Astrophysics Data System (ADS)

Gristina, S.; Ellul, C.; Scianna, A.

2016-10-01

Road transport has always played an important role in a country's growth and, in order to manage road networks and ensure a high standard of road performance (e.g. durability, efficiency and safety), both public and private road inventories have been implemented using databases and Geographical Information Systems. They enable registering and managing significant amounts of different road information, but to date do not focus on 3D road information, data integration and interoperability. In an increasingly complex 3D urban environment, and in the age of smart cities, however, applications including intelligent transport systems, mobility and traffic management, road maintenance and safety require digital data infrastructures to manage road data: thus new inventories based on integrated 3D road models (queryable, updateable and shareable on line) are required. This paper outlines the first step towards the implementation of 3D GIS-based road inventories. Focusing on the case study of the "Road Cadastre" (the Italian road inventory as established by law), it investigates current limitations and required improvements, and also compares the required data structure imposed by cadastral legislation with real road users' needs. The study aims to: a) determine whether 3D GIS would improve road cadastre (for better management of data through the complete life-cycle infrastructure projects); b) define a conceptual model for a 3D road cadastre for Italy (whose general principles may be extended also to other countries).

3D Technology Selection for a Virtual Learning Environment by Blending ISO 9126 Standard and AHP

ERIC Educational Resources Information Center

Cetin, Aydin; Guler, Inan

2011-01-01

Web3D presents many opportunities for learners in a virtual world or virtual environment over the web. This is a great opportunity for open-distance education institutions to benefit from web3d technologies to create courses with interactive 3d materials. There are many open source and commercial products offering 3d technologies over the web…

The Development of Ada (Trademark) Software for Secure Environments

DTIC Science & Technology

1986-05-23

Telecommunications environment, This paper discusses software socurity and seeks to demostrate how the Ada programming language can be utilizec as a tool...complexity 4 . We use abstraction in our lives every day to control complexity; the principles of abstraction for software engineering are ro different...systems. These features directly sup,) )-t t.ie m odernp software engineering principles d1 s I , , 1 t, thne previous section. This is not surprising

Using articulated scene models for dynamic 3d scene analysis in vista spaces

NASA Astrophysics Data System (ADS)

Beuter, Niklas; Swadzba, Agnes; Kummert, Franz; Wachsmuth, Sven

2010-09-01

In this paper we describe an efficient but detailed new approach to analyze complex dynamic scenes directly in 3D. The arising information is important for mobile robots to solve tasks in the area of household robotics. In our work a mobile robot builds an articulated scene model by observing the environment in the visual field or rather in the so-called vista space. The articulated scene model consists of essential knowledge about the static background, about autonomously moving entities like humans or robots and finally, in contrast to existing approaches, information about articulated parts. These parts describe movable objects like chairs, doors or other tangible entities, which could be moved by an agent. The combination of the static scene, the self-moving entities and the movable objects in one articulated scene model enhances the calculation of each single part. The reconstruction process for parts of the static scene benefits from removal of the dynamic parts and in turn, the moving parts can be extracted more easily through the knowledge about the background. In our experiments we show, that the system delivers simultaneously an accurate static background model, moving persons and movable objects. This information of the articulated scene model enables a mobile robot to detect and keep track of interaction partners, to navigate safely through the environment and finally, to strengthen the interaction with the user through the knowledge about the 3D articulated objects and 3D scene analysis. [Figure not available: see fulltext.

Overview of 3D-TRACE, a NASA Initiative in Three-Dimensional Tomography of the Aerosol-Cloud Environment

NASA Astrophysics Data System (ADS)

Davis, Anthony; Diner, David; Yanovsky, Igor; Garay, Michael; Xu, Feng; Bal, Guillaume; Schechner, Yoav; Aides, Amit; Qu, Zheng; Emde, Claudia

2013-04-01

Remote sensing is a key tool for sorting cloud ensembles by dynamical state, aerosol environments by source region, and establishing causal relationships between aerosol amounts, type, and cloud microphysics-the so-called indirect aerosol climate impacts, and one of the main sources of uncertainty in current climate models. Current satellite imagers use data processing approaches that invariably start with cloud detection/masking to isolate aerosol air-masses from clouds, and then rely on one-dimensional (1D) radiative transfer (RT) to interpret the aerosol and cloud measurements in isolation. Not only does this lead to well-documented biases for the estimates of aerosol radiative forcing and cloud optical depths in current missions, but it is fundamentally inadequate for future missions such as EarthCARE where capturing the complex, three-dimensional (3D) interactions between clouds and aerosols is a primary objective. In order to advance the state of the art, the next generation of satellite information processing systems must incorporate technologies that will enable the treatment of the atmosphere as a fully 3D environment, represented more realistically as a continuum. At one end, there is an optically thin background dominated by aerosols and molecular scattering that is strongly stratified and relatively homogeneous in the horizontal. At the other end, there are optically thick embedded elements, clouds and aerosol plumes, which can be more or less uniform and quasi-planar or else highly 3D with boundaries in all directions; in both cases, strong internal variability may be present. To make this paradigm shift possible, we propose to combine the standard models for satellite signal prediction physically grounded in 1D and 3D RT, both scalar and vector, with technologies adapted from biomedical imaging, digital image processing, and computer vision. This will enable us to demonstrate how the 3D distribution of atmospheric constituents, and their associated microphysical properties, can be reconstructed from multi-angle/multi-spectral imaging radiometry and, more and more, polarimetry. Specific technologies of interest are computed tomography (reconstruction from projections), optical tomography (using cross-pixel radiation transport in the diffusion limit), stereoscopy (depth/height retrievals), blind source and scale separation (signal unmixing), and disocclusion (information recovery in the presence of obstructions). Later on, these potentially powerful inverse problem solutions will be fully integrated in a versatile satellite data analysis toolbox. At present, we can report substantial progress at the component level. Specifically, we will focus on the most elementary problems in atmospheric tomography with an emphasis on the vastly under-exploited class of multi-pixel techniques. One basic problem is to infer the outer shape and mean opacity of 3D clouds, along with a bulk measure of cloud particle size. Another is to separate high and low cloud layers based on their characteristically different spatial textures. Yet another is to reconstruct the 3D spatial distribution of aerosol density based on passive imaging. This suite of independent feasibility studies amounts to a compelling proofof- concept for the ambitious 3D-Tomographic Reconstruction of the Aerosol-Cloud Environment (3D-TRACE) project as a whole.

Methodology for assessing thioarsenic formation potential in sulfidic landfill environments.

PubMed

Zhang, Jianye; Kim, Hwidong; Townsend, Timothy

2014-07-01

Arsenic leaching and speciation in landfills, especially those with arsenic bearing waste and drywall disposal (such as construction and demolition (C&D) debris landfills), may be affected by high levels of sulfide through the formation of thioarsenic anions. A methodology using ion chromatography (IC) with a conductivity detector was developed for the assessment of thioarsenic formation potential in sulfidic landfill environments. Monothioarsenate (H2AsSO3(-)) and dithioarsenate (H2AsS2O2(-)) were confirmed in the IC fractions of thioarsenate synthesis mixture, consistent with previous literature results. However, the observation of AsSx(-) (x=5-8) in the supposed trithioarsenate (H2AsS3O(-)) and tetrathioarsenate (H2AsS4(-)) IC fractions suggested the presence of new arsenic polysulfide complexes. All thioarsenate anions, particularly trithioarsenate and tetrathioarsenate, were unstable upon air exposure. The method developed for thioarsenate analysis was validated and successfully used to analyze several landfill leachate samples. Thioarsenate anions were detected in the leachate of all of the C&D debris landfills tested, which accounted for approximately 8.5% of the total aqueous As in the leachate. Compared to arsenite or arsenate, thioarsenates have been reported in literature to have lower adsorption on iron oxide minerals. The presence of thioarsenates in C&D debris landfill leachate poses new concerns when evaluating the impact of arsenic mobilization in such environments. Copyright © 2014 Elsevier Ltd. All rights reserved.

3dRPC: a web server for 3D RNA-protein structure prediction.

PubMed

Huang, Yangyu; Li, Haotian; Xiao, Yi

2018-04-01

RNA-protein interactions occur in many biological processes. To understand the mechanism of these interactions one needs to know three-dimensional (3D) structures of RNA-protein complexes. 3dRPC is an algorithm for prediction of 3D RNA-protein complex structures and consists of a docking algorithm RPDOCK and a scoring function 3dRPC-Score. RPDOCK is used to sample possible complex conformations of an RNA and a protein by calculating the geometric and electrostatic complementarities and stacking interactions at the RNA-protein interface according to the features of atom packing of the interface. 3dRPC-Score is a knowledge-based potential that uses the conformations of nucleotide-amino-acid pairs as statistical variables and that is used to choose the near-native complex-conformations obtained from the docking method above. Recently, we built a web server for 3dRPC. The users can easily use 3dRPC without installing it locally. RNA and protein structures in PDB (Protein Data Bank) format are the only needed input files. It can also incorporate the information of interface residues or residue-pairs obtained from experiments or theoretical predictions to improve the prediction. The address of 3dRPC web server is http://biophy.hust.edu.cn/3dRPC. yxiao@hust.edu.cn.

Learning in 3D Virtual Environments: Collaboration and Knowledge Spirals

ERIC Educational Resources Information Center

Burton, Brian G.; Martin, Barbara N.

2010-01-01

The purpose of this case study was to determine if learning occurred within a 3D virtual learning environment by determining if elements of collaboration and Nonaka and Takeuchi's (1995) knowledge spiral were present. A key portion of this research was the creation of a Virtual Learning Environment. This 3D VLE utilized the Torque Game Engine…

A systematic review on in vitro 3D bone metastases models: A new horizon to recapitulate the native clinical scenario?

PubMed

Salamanna, Francesca; Contartese, Deyanira; Maglio, Melania; Fini, Milena

2016-07-12

While the skeleton is not the only organ where metastasis can occur, it is one of the preferred sites, with a significant impact in patients' quality of life. With the aim of delineating the cellular and molecular mechanisms of bone metastasis, numerous studies have been employed to identify any contributing factors that trigger cancer progression. One of the major limitations of studying cancer-bone metastasis is the multifaceted nature of the native bone environment and the lack of reliable, simple, and not expensive models that strictly mimic the biological processes occurring in vivo allowing a correct translation of results. Currently, with the growing acceptance of in vitro models as effective tools for studying cancer biology, three-dimensional (3D) models have emerged as a compromise between two-dimensional cultures of isolated cancer cells and the complexity of human cancer xenografts in immunocompromised animal hosts. This descriptive systematic literature review summarizes the current status of advanced and alternative 3D in vitro bone metastases models. We have also reviewed the strategies employed by researchers to set-up these models with special reference to recent promising developments trying to better replicate the complexity and heterogeneity of a human metastasis in situ, with an outlook at their use in medicine. All these aspects will greatly contribute to the existing knowledge on bone metastases, providing a specific link to clinical scenarios and thus making 3D in vitro bone metastasis models an attractive tool for multidisciplinary experts.

Development of a stereoscopic three-dimensional drawing application

NASA Astrophysics Data System (ADS)

Carver, Donald E.; McAllister, David F.

1991-08-01

With recent advances in 3-D technology, computer users have the opportunity to work within a natural 3-D environment; a flat panel LCD computer display of this type, the DTI-100M made by Dimension Technologies, Inc., recently went on the market. In a joint venture between DTI and NCSU, an object-oriented 3-D drawing application, 3-D Draw, was developed to address some issues of human interface design for interactive stereo drawing applications. The focus of this paper is to determine some of the procedures a user would naturally expect to follow while working within a true 3-D environment. The paper discusses (1) the interface between the Macintosh II and DTI-100M during implementation of 3-D Draw, including stereo cursor development and presentation of current 2-D systems, with an additional `depth'' parameter, in the 3-D world, (2) problems in general for human interface into the 3-D environment, and (3) necessary functions and/or problems in developing future stereoscopic 3-D operating systems/tools.

Memory and visual search in naturalistic 2D and 3D environments

PubMed Central

Li, Chia-Ling; Aivar, M. Pilar; Kit, Dmitry M.; Tong, Matthew H.; Hayhoe, Mary M.

2016-01-01

The role of memory in guiding attention allocation in daily behaviors is not well understood. In experiments with two-dimensional (2D) images, there is mixed evidence about the importance of memory. Because the stimulus context in laboratory experiments and daily behaviors differs extensively, we investigated the role of memory in visual search, in both two-dimensional (2D) and three-dimensional (3D) environments. A 3D immersive virtual apartment composed of two rooms was created, and a parallel 2D visual search experiment composed of snapshots from the 3D environment was developed. Eye movements were tracked in both experiments. Repeated searches for geometric objects were performed to assess the role of spatial memory. Subsequently, subjects searched for realistic context objects to test for incidental learning. Our results show that subjects learned the room-target associations in 3D but less so in 2D. Gaze was increasingly restricted to relevant regions of the room with experience in both settings. Search for local contextual objects, however, was not facilitated by early experience. Incidental fixations to context objects do not necessarily benefit search performance. Together, these results demonstrate that memory for global aspects of the environment guides search by restricting allocation of attention to likely regions, whereas task relevance determines what is learned from the active search experience. Behaviors in 2D and 3D environments are comparable, although there is greater use of memory in 3D. PMID:27299769

Contributions of divergent and nondivergent winds to the kinetic energy balance of a severe storm environment

NASA Technical Reports Server (NTRS)

Browning, P. A.; Fuelberg, H. E.

1983-01-01

Divergent and rotational components of the synoptic scale kinetic energy balance are presented using rawinsonde data at 3 and 6 h intervals from the Atmospheric Variability Experiment (AVE 4). Two intense thunderstorm complexes occurred during the period. Energy budgets are described for the entire computational region and for limited volumes that enclose and move with the convection. Although small in magnitude, the divergent wind component played an important role in the cross contour generation and horizontal flux divergence of kinetic energy. The importance of V sub D appears directly to the presence and intensity of convection within the area. Although K sub D usually comprised less than 10 percent of the total kinetic energy content within the storm environment, as much as 87 percent of the total horizontal flux divergence and 68 percent of the total cross contour generation was due to the divergent component in the upper atmosphere. Generation of kinetic energy by the divergent component appears to be a major factor in the creation of an upper level wind maximum on the poleward side of one of the complexes. A random error analysis is presented to assess confidence limits in the various energy parameters.

Evaluation of an interactive science publishing tool: toward enabling three-dimensional analysis of medical images.

PubMed

Rinewalt, Daniel; Williams, Betsy W; Reeves, Anthony P; Shah, Palmi; Hong, Edward; Mulshine, James L

2015-03-01

Higher resolution medical imaging platforms are rapidly emerging, but there is a challenge in applying these tools in a clinically meaningful way. The purpose of the current study was to evaluate a novel three-dimensional (3D) software imaging environment, known as interactive science publishing (ISP), in appraising 3D computed tomography images and to compare this approach with traditional planar (2D) imaging in a series of lung cancer cases. Twenty-four physician volunteers at different levels of training across multiple specialties were recruited to evaluate eight lung cancer-related clinical vignettes. The volunteers were asked to compare the performance of traditional 2D versus the ISP 3D imaging in assessing different visualization environments for diagnostic and measurement processes and to further evaluate the ISP tool in terms of general satisfaction, usability, and probable applicability. Volunteers were satisfied with both imaging methods; however, the 3D environment had significantly higher ratings. Measurement performance was comparable using both traditional 2D and 3D image evaluation. Physicians not trained in 2D measurement approaches versus those with such training demonstrated better performance with ISP and preferred working in the ISP environment. Recent postgraduates with only modest self-administered training performed equally well on 3D and 2D cases. This suggests that the 3D environment has no reduction in accuracy over the conventional 2D approach, while providing the advantage of a digital environment for cross-disciplinary interaction for shared problem solving. Exploration of more effective, efficient, self-directed training could potentially result in further improvement in image evaluation proficiency and potentially decrease training costs. Copyright © 2015. Published by Elsevier Inc.

Assembly and property research on seven 0D–3D complexes derived from imidazole dicarboxylate and 1,2-bi(pyridin-4-yl)ethene

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mu, Bao; Li, Qian; Lv, Lei

2015-03-15

The hydrothermal reaction of transition metals, 1H-imidazole-4,5-dicarboxylic acid (H{sub 3}ImDC) and 1,2-bi(pyridin-4-yl)ethene (bpe) affords a series of new complexes, namely, [Mn(HImDC)(bpe)(H{sub 2}O)] (1), [M(H{sub 2}ImDC){sub 2}(H{sub 2}O){sub 2}]·(bpe) (M=Fe(2), Co(3), Zn(4), Cd(6)), [Zn{sub 3}(ImDC){sub 2}(bpe)(H{sub 2}O)]·3H{sub 2}O (5) and [Cd(H{sub 2}ImDC)(bpe)] (7), which are characterized by elemental analyses, IR, TG, XRPD and single crystal X-ray diffraction. Complex 1 exhibits a one dimensional (1D) zigzag chain with two types of irregular rings, and the 1D chains are linked to form a three dimensional (3D) supramolecular framework by the hydrogen bonding interactions (O–H∙∙∙O and O–H∙∙∙N). Complexes 2–4 and 6 are isomorphous, andmore » they display the mononuclear structures. In these complexes, the O–H∙∙∙O and O–H∙∙∙N hydrogen bonds play an important role in sustaining the whole 3D supramolecular frameworks. Complex 5 shows a (3,3)-connected 3D framework with (10{sup 3}) topology, and the lattice water molecules as guest molecules exist in the 3D framework. Complex 7 is a wave-like two dimensional (2D) structure, in which the adjacent 1D chains point at the opposite directions. Moreover, the fluorescent properties of complexes 1–7 and the magnetic property of 1 have been investigated. The water vapor adsorption for complex 5 has been researched at 298 K. - Graphical abstract: Seven new complexes based on different structural characteristics have been hydrothermally synthesized by the mixed ligands. The fluorescent properties, the magnetic property and the water vapor adsorption have been investigated. - Highlights: • The semi-rigid ligand with C=C bonds and imidazole dicarboxylates with some advantages have been used. • A series of new complexes with different structural characteristics have been discussed in detail. • The fluorescent properties, the magnetic property and the water vapor adsorption have been investigated.« less

The complex behavior of the Pd 7 cluster supported on TiO 2 (110) during CO oxidation: adsorbate-driven promoting effect

DOE PAGES

An, Wei; Liu, Ping

2016-09-07

When using the TiO 2(110)-supported Pd7 cluster as a model catalyst, we identified the dynamics of supported metal nanoparticles using density functional theory calculations, at the sub-nanometer scale and under reactive environments. Increasing the CO coverage can induce a structural transformation from Pd 7-3D/TiO 2(110) at low coverage to Pd 7-2D/TiO 2(110) at the saturation coverage wherein CO saturation-driven Pd7-2D/TiO 2(110) structure displays superior CO oxidation activity at the interfacial sites, which are highly active for catalyzing O 2 dissociation and CO oxidation via bifunctional synergy.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Yazhen; Musser, Sarah K.; Saleh, Sam

1,N{sup 2}-Propanodeoxyguanosine (PdG) is a stable structural analogue for the 3-(2'-deoxy-{beta}-d-erythro-pentofuranosyl)pyrimido[1,2-?]purin-10(3H)-one (M{sub 1}dG) adduct derived from exposure of DNA to base propenals and to malondialdehyde. The structures of ternary polymerase-DNA-dNTP complexes for three template-primer DNA sequences were determined, with the Y-family Sulfolobus solfataricus DNA polymerase IV (Dpo4), at resolutions between 2.4 and 2.7 {angstrom}. Three template 18-mer-primer 13-mer sequences, 5'-d(TCACXAAATCCTTCCCCC)-3'{center_dot}5'-d(GGGGGAAGGATTT)-3' (template I), 5'-d(TCACXGAATCCTTCCCCC)-3'{center_dot}5'-d(GGGGGAAGGATTC)-3' (template II), and 5'-d(TCATXGAATCCTTCCCCC)-3'{center_dot}5'-d(GGGGGAAGGATTC)-3' (template III), where X is PdG, were analyzed. With templates I and II, diffracting ternary complexes including dGTP were obtained. The dGTP did not pair with PdG, but instead with the 5'-neighboring templatemore » dC, utilizing Watson-Crick geometry. Replication bypass experiments with the template-primer 5?-TCACXAAATCCTTACGAGCATCGCCCCC-3'{center_dot}5'-GGGGGCGATGCTCGTAAGGATTT-3', where X is PdG, which includes PdG in the 5'-CXA-3' template sequence as in template I, showed that the Dpo4 polymerase inserted dGTP and dATP when challenged by the PdG adduct. For template III, in which the template sequence was 5'-TXG-3', a diffracting ternary complex including dATP was obtained. The dATP did not pair with PdG, but instead with the 5'-neighboring T, utilizing Watson-Crick geometry. Thus, all three ternary complexes were of the 'type II' structure described for ternary complexes with native DNA [Ling, H., Boudsocq, F., Woodgate, R., and Yang, W. (2001) Cell 107, 91--102]. The PdG adduct remained in the anti conformation about the glycosyl bond in each of these threee ternary complexes. These results provide insight into how -1 frameshift mutations might be generated for the PdG adduct, a structural model for the exocylic M{sub 1}dG adduct formed by malondialdehyde.« less

H3K9me3 demethylase Kdm4d facilitates the formation of pre-initiative complex and regulates DNA replication

PubMed Central

Wu, Rentian; Wang, Zhiquan; Zhang, Honglian; Gan, Haiyun; Zhang, Zhiguo

2017-01-01

DNA replication is tightly regulated to occur once and only once per cell cycle. How chromatin, the physiological substrate of DNA replication machinery, regulates DNA replication remains largely unknown. Here we show that histone H3 lysine 9 demethylase Kdm4d regulates DNA replication in eukaryotic cells. Depletion of Kdm4d results in defects in DNA replication, which can be rescued by the expression of H3K9M, a histone H3 mutant transgene that reverses the effect of Kdm4d on H3K9 methylation. Kdm4d interacts with replication proteins, and its recruitment to DNA replication origins depends on the two pre-replicative complex components (origin recognition complex [ORC] and minichromosome maintenance [MCM] complex). Depletion of Kdm4d impairs the recruitment of Cdc45, proliferating cell nuclear antigen (PCNA), and polymerase δ, but not ORC and MCM proteins. These results demonstrate a novel mechanism by which Kdm4d regulates DNA replication by reducing the H3K9me3 level to facilitate formation of pre-initiative complex. PMID:27679476

Historical Buildings Models and Their Handling via 3d Survey: from Points Clouds to User-Oriented Hbim

NASA Astrophysics Data System (ADS)

Chiabrando, F.; Sammartano, G.; Spanò, A.

2016-06-01

This paper retraces some research activities and application of 3D survey techniques and Building Information Modelling (BIM) in the environment of Cultural Heritage. It describes the diffusion of as-built BIM approach in the last years in Heritage Assets management, the so-called Built Heritage Information Modelling/Management (BHIMM or HBIM), that is nowadays an important and sustainable perspective in documentation and administration of historic buildings and structures. The work focuses the documentation derived from 3D survey techniques that can be understood like a significant and unavoidable knowledge base for the BIM conception and modelling, in the perspective of a coherent and complete management and valorisation of CH. It deepens potentialities, offered by 3D integrated survey techniques, to acquire productively and quite easilymany 3D information, not only geometrical but also radiometric attributes, helping the recognition, interpretation and characterization of state of conservation and degradation of architectural elements. From these data, they provide more and more high descriptive models corresponding to the geometrical complexity of buildings or aggregates in the well-known 5D (3D + time and cost dimensions). Points clouds derived from 3D survey acquisition (aerial and terrestrial photogrammetry, LiDAR and their integration) are reality-based models that can be use in a semi-automatic way to manage, interpret, and moderately simplify geometrical shapes of historical buildings that are examples, as is well known, of non-regular and complex geometry, instead of modern constructions with simple and regular ones. In the paper, some of these issues are addressed and analyzed through some experiences regarding the creation and the managing of HBIMprojects on historical heritage at different scales, using different platforms and various workflow. The paper focuses on LiDAR data handling with the aim to manage and extract geometrical information; on development and optimization of semi-automatic process of segmentation, recognition and modelling of historical shapes of complex structures; on communication of historical heritage by virtual and augmented reality (VR/AR) in a 3D reconstruction of buildings aggregates from a LiDAR and UAV survey. The HBIM model have been implemented and optimized to be managed and browse by mobile devices for not only touristic or informative scopes, but also to ensure that HBIM platforms will become more easy and valuable tools helping all professionals of AEC involved in the documentation and valorisation process, that nowadays more and more distinguish CH policies.

Intermolecular dissociation energies of dispersively bound complexes of aromatics with noble gases and nitrogen

NASA Astrophysics Data System (ADS)

Knochenmuss, Richard; Sinha, Rajeev K.; Leutwyler, Samuel

2018-04-01

We measured accurate intermolecular dissociation energies D0 of the supersonic jet-cooled complexes of 1-naphthol (1NpOH) with the noble gases Ne, Ar, Kr, and Xe and with N2, using the stimulated-emission pumping resonant two-photon ionization method. The ground-state values D0(S0) for the 1NpOHṡS complexes with S= Ar, Kr, Xe, and N2 were bracketed to be within ±3.5%; they are 5.67 ± 0.05 kJ/mol for S = Ar, 7.34 ± 0.07 kJ/mol for S = Kr, 10.8 ± 0.28 kJ/mol for S = Xe, 6.67 ± 0.08 kJ/mol for isomer 1 of the 1NpOHṡN2 complex, and 6.62 ± 0.22 kJ/mol for the corresponding isomer 2. For S = Ne, the upper limit is D0 < 3.36 kJ/mol. The dissociation energies increase by 1%-5% upon S0 → S1 excitation of the complexes. Three dispersion-corrected density functional theory (DFT-D) methods (B97-D3, B3LYP-D3, and ωB97X-D) predict that the most stable form of these complexes involves dispersive binding to the naphthalene "face." A more weakly bound edge isomer is predicted in which the S moiety is H-bonded to the OH group of 1NpOH; however, no edge isomers were observed experimentally. The B97-D3 calculated dissociation energies D0(S0) of the face complexes with Ar, Kr, and N2 agree with the experimental values within <5%, but the D0(S0) for Xe is 12% too low. The B3LYP-D3 and ωB97X-D calculated D0(S0) values exhibit larger deviations to both larger and smaller dissociation energies. For comparison to 1-naphthol, we calculated the D0(S0) of the carbazole complexes with S = Ne, Ar, Kr, Xe, and N2 using the same DFT-D methods. The respective experimental values have been previously determined to be within <2%. Again, the B97-D3 results are in the best overall agreement with experiment.

Corner flow control in high through-flow axial commercial fan/booster using blade 3-D optimization

NASA Astrophysics Data System (ADS)

Zhu, Fang; Jin, Donghai; Gui, Xingmin

2012-02-01

This study is aimed at using blade 3-D optimization to control corner flows in the high through-flow fan/booster of a high bypass ratio commercial turbofan engine. Two kinds of blade 3-D optimization, end-bending and bow, are focused on. On account of the respective operation mode and environment, the approach to 3-D aerodynamic modeling of rotor blades is different from stator vanes. Based on the understanding of the mechanism of the corner flow and the consideration of intensity problem for rotors, this paper uses a variety of blade 3-D optimization approaches, such as loading distribution optimization, perturbation of departure angles and stacking-axis manipulation, which are suitable for rotors and stators respectively. The obtained 3-D blades and vanes can improve the corner flow features by end-bending and bow effects. The results of this study show that flows in corners of the fan/booster, such as the fan hub region, the tip and hub of the vanes of the booster, are very complex and dominated by 3-D effects. The secondary flows there are found to have a strong detrimental effect on the compressor performance. The effects of both end-bending and bow can improve the flow separation in corners, but the specific ways they work and application scope are somewhat different. Redesigning the blades via blade 3-D optimization to control the corner flow has effectively reduced the loss generation and improved the stall margin by a large amount.

EEG-based cognitive load of processing events in 3D virtual worlds is lower than processing events in 2D displays.

PubMed

Dan, Alex; Reiner, Miriam

2017-12-01

Interacting with 2D displays, such as computer screens, smartphones, and TV, is currently a part of our daily routine; however, our visual system is built for processing 3D worlds. We examined the cognitive load associated with a simple and a complex task of learning paper-folding (origami) by observing 2D or stereoscopic 3D displays. While connected to an electroencephalogram (EEG) system, participants watched a 2D video of an instructor demonstrating the paper-folding tasks, followed by a stereoscopic 3D projection of the same instructor (a digital avatar) illustrating identical tasks. We recorded the power of alpha and theta oscillations and calculated the cognitive load index (CLI) as the ratio of the average power of frontal theta (Fz.) and parietal alpha (Pz). The results showed a significantly higher cognitive load index associated with processing the 2D projection as compared to the 3D projection; additionally, changes in the average theta Fz power were larger for the 2D conditions as compared to the 3D conditions, while alpha average Pz power values were similar for 2D and 3D conditions for the less complex task and higher in the 3D state for the more complex task. The cognitive load index was lower for the easier task and higher for the more complex task in 2D and 3D. In addition, participants with lower spatial abilities benefited more from the 3D compared to the 2D display. These findings have implications for understanding cognitive processing associated with 2D and 3D worlds and for employing stereoscopic 3D technology over 2D displays in designing emerging virtual and augmented reality applications. Copyright © 2016 Elsevier B.V. All rights reserved.

Synthesis, characterization and solid state electrical properties of 1-D coordination polymer of the type [CuxNi1-x(dadb)·yH2O]n

NASA Astrophysics Data System (ADS)

Prasad, R. L.; Kushwaha, A.; Shrivastava, O. N.

2012-12-01

New heterobimetallic complexes [CuxNi1-x(dadb)·yH2O]n {where dadb=2,5-Diamino-3,6-dichloro-1,4-benzoquinone (1); x=1 (2), 0.5 (4), 0.25 (5), 0.125 (6), 0.0625 (7) and 0 (3); y=2; n=degree of polymerization} were synthesized and characterized. Heterobimetallic complexes show normal magnetic moments, whereas, monometallic complexes exhibit magnetic moments less than the value due to spin only. Thermo-gravimetric analysis shows that degradation of the ligand dadb moiety is being controlled by the electronic environment of the Cu(II) ions in preference over Ni(II) in heterobimetallic complexes. Existence of the mixed valency/non-integral oxidation states of copper and nickel metal ions in the complex 4 has been attributed from magnetic moment and ESR spectral results. Solid state dc electrical conductivity of all the complexes was investigated. Monometallic complexes were found to be semiconductors, whereas heterobimetallic coordination polymer 4 was found to exhibit metallic behaviour. Existence of mixed valency/ non-integral oxidation state of metal ions seems to be responsible for the metallic behaviour.

Downhole seismic monitoring with Virtual Sources

NASA Astrophysics Data System (ADS)

Bakulin, A.; Calvert, R.

2005-12-01

Huge quantities of remaining oil and gas reserves are located in very challenging geological environments covered by salt, basalt or other complex overburdens. Conventional surface seismology struggles to deliver images necessary to economically explore them. Even if those reserves are found by drilling successful production critically depends on our ability to ``see" in real time where fluids are drawn from and how pressure changes throughout the reservoirs. For relatively simple overburdens surface time-lapse (4D) seismic monitoring became industry choice for aerial reservoir surveillance. For complex overburdens, 4D seismic does not have enough resolution and repeatability to answer the questions of reservoir engineers. For instance, often reservoir changes are too small to be detected from surface or these changes occur in such pace that all wells will be placed before we can detect them which greatly reduces the economical impact. Two additional challenges are present in real life that further complicate active monitoring: first, near-surface condition do change between the surveys (water level movement, freezing/thawing, tide variations etc) and second, repeating exact same acquisition geometry at the surface is difficult in practice. Both of these things may lead to false 4D response unrelated to reservoir changes. Virtual Source method (VSM) has been recently proposed as a way to eliminate overburden distortions for imaging and monitoring. VSM acknowledges upfront that our data inversion techniques are unable to unravel the details of the complex overburdens to the extent necessary to remove the distortions caused by them. Therefore VSM advocates placing permanent downhole geophones below that most complex overburden while still exciting signals with a surface sources. For instance, first applications include drilling instrumented wells below complicated near-surface, basalt or salt layer. Of course, in an ideal world we would prefer to have both downhole sources and receivers (e.g. in-situ 4D seismic), but for now VSM may be the most economical alternative. By performing data-driven redatuming with measured Green's functions, these data can be recast into complete downhole dataset with buried Virtual Sources located at each downhole geophone. This step can be effectively thought of as a time reversal and it's remarkable feature is that velocity model between sources and receivers is not required to perform it. We will show various applications of the VSM method to several synthetic and real time-lapse datasets to illustrate the following advantages: 1) ability of VSM to eliminate overburden distortions without knowing velocity model between surface sources and downhole receivers, 2) greater quality of Virtual Sources in strongly scattering environment, 3) beneficial downward only radiation pattern on the Virtual Sources, 4) ability to correct non-repeatability caused by slight changes in acquisition geometry and temporal changes in the near surface, 5) ability to create P-wave Virtual Sources without shear radiation and S-sources without P-waves. Versatility of VSM to handle 1D, 2D and 3D situations and its ability to handle overburdens of any complexity makes it an indispensable tool for the active geophysical monitoring in a challenging geological environments. Although examples presented all come from an oilfield, it is straightforward to envision analogous applications in many other fields ranging from global geophysics to monitoring man-made structures.

An in vitro 3D bone metastasis model by using a human bone tissue culture and human sex-related cancer cells.

PubMed

Salamanna, Francesca; Borsari, Veronica; Brogini, Silvia; Giavaresi, Gianluca; Parrilli, Annapaola; Cepollaro, Simona; Cadossi, Matteo; Martini, Lucia; Mazzotti, Antonio; Fini, Milena

2016-11-22

One of the main limitations, when studying cancer-bone metastasis, is the complex nature of the native bone environment and the lack of reliable, simple, inexpensive models that closely mimic the biological processes occurring in patients and allowing the correct translation of results. To enhance the understanding of the mechanisms underlying human bone metastases and in order to find new therapies, we developed an in vitro three-dimensional (3D) cancer-bone metastasis model by culturing human breast or prostate cancer cells with human bone tissue isolated from female and male patients, respectively. Bone tissue discarded from total hip replacement surgery was cultured in a rolling apparatus system in a normoxic or hypoxic environment. Gene expression profile, protein levels, histological, immunohistochemical and four-dimensional (4D) micro-CT analyses showed a noticeable specificity of breast and prostate cancer cells for bone colonization and ingrowth, thus highlighting the species-specific and sex-specific osteotropism and the need to widen the current knowledge on cancer-bone metastasis spread in human bone tissues. The results of this study support the application of this model in preclinical studies on bone metastases and also follow the 3R principles, the guiding principles, aimed at replacing/reducing/refining (3R) animal use and their suffering for scientific purposes.

An in vitro 3D bone metastasis model by using a human bone tissue culture and human sex-related cancer cells

PubMed Central

Salamanna, Francesca; Borsari, Veronica; Brogini, Silvia; Giavaresi, Gianluca; Parrilli, Annapaola; Cepollaro, Simona; Cadossi, Matteo; Martini, Lucia; Mazzotti, Antonio; Fini, Milena

2016-01-01

One of the main limitations, when studying cancer-bone metastasis, is the complex nature of the native bone environment and the lack of reliable, simple, inexpensive models that closely mimic the biological processes occurring in patients and allowing the correct translation of results. To enhance the understanding of the mechanisms underlying human bone metastases and in order to find new therapies, we developed an in vitro three-dimensional (3D) cancer-bone metastasis model by culturing human breast or prostate cancer cells with human bone tissue isolated from female and male patients, respectively. Bone tissue discarded from total hip replacement surgery was cultured in a rolling apparatus system in a normoxic or hypoxic environment. Gene expression profile, protein levels, histological, immunohistochemical and four-dimensional (4D) micro-CT analyses showed a noticeable specificity of breast and prostate cancer cells for bone colonization and ingrowth, thus highlighting the species-specific and sex-specific osteotropism and the need to widen the current knowledge on cancer-bone metastasis spread in human bone tissues. The results of this study support the application of this model in preclinical studies on bone metastases and also follow the 3R principles, the guiding principles, aimed at replacing/reducing/refining (3R) animal use and their suffering for scientific purposes. PMID:27765913

Delicate crystal structure changes govern the magnetic properties of 1D coordination polymers based on 3d metal carboxylates.

PubMed

Gavrilenko, Konstantin S; Cador, Olivier; Bernot, Kevin; Rosa, Patrick; Sessoli, Roberta; Golhen, Stéphane; Pavlishchuk, Vitaly V; Ouahab, Lahcène

2008-01-01

Homo- and heterometallic 1D coordination polymers of transition metals (Co II, Mn II, Zn II) have been synthesized by an in-situ ligand generation route. Carboxylato-based complexes [Co(PhCOO)2]n (1 a, 1 b), [Co(p-MePhCOO)2]n (2), [ZnMn(PhCOO)4]n (3), and [CoZn(PhCOO)4]n (4) (PhCOOH=benzoic acid, p-MePhCOOH=p-methylbenzoic acid) have been characterized by chemical analysis, single-crystal X-ray diffraction, and magnetization measurements. The new complexes 2 and 3 crystallize in orthorhombic space groups Pnab and Pcab respectively. Their crystal structures consist of zigzag chains, with alternating M(II) centers in octahedral and tetrahedral positions, which are similar to those of 1 a and 1 b. Compound 4 crystallizes in monoclinic space group P2 1/c and comprises zigzag chains of M II ions in a tetrahedral coordination environment. Magnetic investigations reveal the existence of antiferromagnetic interactions between magnetic centers in the heterometallic complexes 3 and 4, while ferromagnetic interactions operate in homometallic compounds (1 a, 1 b, and 2). Compound 1 b orders ferromagnetically at TC=3.7 K whereas 1 a does not show any magnetic ordering down to 330 mK and displays typical single-chain magnet (SCM) behavior with slowing down of magnetization relaxation below 0.6 K. Single-crystal measurements reveal that the system is easily magnetized in the chain direction for 1 a whereas the chain direction coincides with the hard magnetic axis in 1 b. Despite important similarities, small differences in the molecular and crystal structures of these two compounds lead to this dramatic change in properties.

A co-culture system with three different primary human cell populations reveals that biomaterials and MSC modulate macrophage-driven fibroblast recruitment.

PubMed

Caires, Hugo R; Barros da Silva, Patrícia; Barbosa, Mário A; Almeida, Catarina R

2018-03-01

The biological response to implanted biomaterials is a complex and highly coordinated phenomenon involving many different cell types that interact within 3D microenvironments. Here, we increased the complexity of a 3D platform to include at least 3 cell types that play a role in the host response upon scaffold implantation. With this system, it was possible to address how immune responses triggered by 3D biomaterials mediate recruitment of stromal cells that promote tissue regeneration, mesenchymal stromal/stem cells (MSC), or a foreign body response, fibroblasts. Primary human macrophages yielded the highest fibroblast recruitment when interacting with chitosan scaffolds but not polylactic acid. Interestingly, when there were MSC and fibroblasts in the same environment, macrophages in chitosan scaffolds again promoted a significant increase on fibroblast recruitment, but not of MSC. However, macrophages that were firstly allowed to interact with MSC within the scaffolds were no longer able to recruit fibroblasts. This study illustrates the potential to use different scaffolds to regulate the dynamics of recruitment of proregenerative or fibrotic cell types through immunomodulation. Overall, this work strengths the idea that ex vivo predictive systems need to consider the different players involved in the biological response to biomaterials and that timing of arrival of specific cell types will affect the outcome. Copyright © 2017 John Wiley & Sons, Ltd.

Virtual environment display for a 3D audio room simulation

NASA Astrophysics Data System (ADS)

Chapin, William L.; Foster, Scott

1992-06-01

Recent developments in virtual 3D audio and synthetic aural environments have produced a complex acoustical room simulation. The acoustical simulation models a room with walls, ceiling, and floor of selected sound reflecting/absorbing characteristics and unlimited independent localizable sound sources. This non-visual acoustic simulation, implemented with 4 audio ConvolvotronsTM by Crystal River Engineering and coupled to the listener with a Poihemus IsotrakTM, tracking the listener's head position and orientation, and stereo headphones returning binaural sound, is quite compelling to most listeners with eyes closed. This immersive effect should be reinforced when properly integrated into a full, multi-sensory virtual environment presentation. This paper discusses the design of an interactive, visual virtual environment, complementing the acoustic model and specified to: 1) allow the listener to freely move about the space, a room of manipulable size, shape, and audio character, while interactively relocating the sound sources; 2) reinforce the listener's feeling of telepresence into the acoustical environment with visual and proprioceptive sensations; 3) enhance the audio with the graphic and interactive components, rather than overwhelm or reduce it; and 4) serve as a research testbed and technology transfer demonstration. The hardware/software design of two demonstration systems, one installed and one portable, are discussed through the development of four iterative configurations. The installed system implements a head-coupled, wide-angle, stereo-optic tracker/viewer and multi-computer simulation control. The portable demonstration system implements a head-mounted wide-angle, stereo-optic display, separate head and pointer electro-magnetic position trackers, a heterogeneous parallel graphics processing system, and object oriented C++ program code.

Fluorometric and theoretical studies on inclusion complexes of β-cyclodextrin and D-, L-phenylalanine

NASA Astrophysics Data System (ADS)

Aree, Thammarat; Arunchai, Rungthiwa; Koonrugsa, Narongsak; Intasiri, Amarawan

2012-10-01

Inclusion complexes of β-cyclodextrin (β-CD) with L- and D-phenylalanine (Phe) have been characterized in solution by fluorometry and in gas phase by semiempirical PM3 calculations. The unimolar stoichiometric ratio of both β-CD-L-Phe and β-CD-D-Phe complexes and the stability constants (K) were deduced from fluorometric titrations. The β-CD-L-Phe complex is more stable than the β-CD-D-Phe complex as indicated by the larger K values, 21.1 vs. 6.86 M-1. This is consistent with the stabilization energies (ΔEstb) and inclusion geometries obtained from PM3 calculations. The β-CD-L-Phe complex with L-Phe residing in the central β-CD cavity and pointing its COOH group downwards to the O6 end has ΔEstb = -62.7 kJ mol-1, whereas the β-CD-D-Phe complex with D-Phe placing at 3 Å beneath the β-CD O4-plane and pointing its COOH group upwards to the O2/O3 end has ΔEstb = -53.3 kJ mol-1. The unison of host-guest intermolecular hydrogen bonds, hydrophobic interactions and molecular deformations plays an essential role in forming and stabilizing the inclusion complexes. Our results show that the β-CD-L-Phe and β-CD-D-Phe inclusion complexes are relatively stable and differentiable, suggesting the applications of CDs in foods and drugs.

MolPrint3D: Enhanced 3D Printing of Ball-and-Stick Molecular Models

ERIC Educational Resources Information Center

Paukstelis, Paul J.

2018-01-01

The increased availability of noncommercial 3D printers has provided instructors and students improved access to printing technology. However, printing complex ball-and-stick molecular structures faces distinct challenges, including the need for support structures that increase with molecular complexity. MolPrint3D is a software add-on for the…

The Role of Model Complexity in Determining Patterns of Chlorophyll Variability in the Coastal Northwest North Atlantic

NASA Astrophysics Data System (ADS)

Kuhn, A. M.; Fennel, K.; Bianucci, L.

2016-02-01

A key feature of the North Atlantic Ocean's biological dynamics is the annual phytoplankton spring bloom. In the region comprising the continental shelf and adjacent deep ocean of the northwest North Atlantic, we identified two patterns of bloom development: 1) locations with cold temperatures and deep winter mixed layers, where the spring bloom peaks around April and the annual chlorophyll cycle has a large amplitude, and 2) locations with warmer temperatures and shallow winter mixed layers, where the spring bloom peaks earlier in the year, sometimes indiscernible from the fall bloom. These patterns result from a combination of limiting environmental factors and interactions among planktonic groups with different optimal requirements. Simple models that represent the ecosystem with a single phytoplankton (P) and a single zooplankton (Z) group are challenged to reproduce these ecological interactions. Here we investigate the effect that added complexity has on determining spatio-temporal chlorophyll. We compare two ecosystem models, one that contains one P and one Z group, and one with two P and three Z groups. We consider three types of changes in complexity: 1) added dependencies among variables (e.g., temperature dependent rates), 2) modified structural pathways, and 3) added pathways. Subsets of the most sensitive parameters are optimized in each model to replicate observations in the region. For computational efficiency, the parameter optimization is performed using 1D surrogates of a 3D model. We evaluate how model complexity affects model skill, and whether the optimized parameter sets found for each model modify the interpretation of ecosystem functioning. Spatial differences in the parameter sets that best represent different areas hint at the existence of different ecological communities or at physical-biological interactions that are not represented in the simplest model. Our methodology emphasizes the combined use of observations, 1D models to help identifying patterns, and 3D models able to simulate the environment modre realistically, as a means to acquire predictive understanding of the ocean's ecology.

Synthesis and structural characterization of new oxovanadium(IV) complexes derived from azo-5-pyrazolone with prospective medical importance

NASA Astrophysics Data System (ADS)

Bagdatli, Emine; Altuntas, Eylem; Sayin, Ulku

2017-01-01

Four novel o-hydroxy substituted aryl-(msbnd H, sbnd Cl, sbnd Br, sbnd CH3) azo-5-pyrazolone compounds (2a-d, respectively) were synthesized as azo-group containing ligands by diazotization of aryl amines then coupled with 1-(4-chlorophenyl)-3-isopropyl-1H-pyrazol-5(4H)-one (1) and the structures were confirmed by FTIR, UV-Visible, GC-MS or ESI-LCMS and NMR spectroscopic techniques. As a result, the first synthesis of azo-5-pyrazolone based oxovanadium(IV) complexes (3a-d) was achieved by interaction of 2a-d with half equivalent of vanadyl sulphate pentahydrate in a methanolic medium with moderate to high yields (67, 74, 60, 71 for 3a-d, respectively). The resulting complexes were characterized using FTIR, UV-Visible, ESI-LCMS and EPR spectroscopic techniques as well as with thermogravimetric (TG/DTG) analysis. They have the composition [VO(L)2]·H2O; (3a-c) or [VO(L)2]·CH3OH; (3d) where LH is an azo-5-pyrazolone compound as the ligand (2a-d). The electronic spectra of the complexes are typical of oxovanadium(IV) complexes showing a low intensity band near 500 nm. Spectroscopic results have shown that azo-5-pyrazolone compounds have acted bidendate and the coordination sites are hydroxyl-substituent on the -azo phenyl-aromatic ring and the pyrazolone carbonyl-moiety. The thermal data confirm that the complexes have methanol (3a-c) or water (3d) molecule outside the coordination sphere and the complexes show similar thermogravimetric decomposition fragments which are consistent with the proposed structures. A distorted octahedral geometry has been proposed for these complexes mainly with EPR and the other spectral techniques.

New metal-organic complexes based on bis(tetrazole) ligands: Synthesis, structures and properties

NASA Astrophysics Data System (ADS)

Du, Ceng-Ceng; Fan, Jian-Zhong; Wang, Xin-Fang; Zhou, Sheng-Bin; Wang, Duo-Zhi

2017-04-01

In this paper, a series of new complexes, [Zn2(HL1)2(H2O)4]·H2O (1), [Co2(HL1)2]·TEA (2), [Co3(HL1)2(H2L1)2(H2O)4]n (3), [Cu(HL1)(H2O)2]n (4), {[Cu5(HL2)2(OH)4(ClO4)2]·4H2O}n (5) and [Cu2(L3)]n (6) were successfully prepared by utilizing three bis(tetrazole) ligands [bis-(1H-tetrazol-5-ylmethyl)-amine (H3L1), bis-(1H-tetrazol-5-ylethyl)-amine (H3L2) and 1,5-bis(5-tetrazolo)-3-thiapentane (H2L3)], all of which have been characterized by elemental analyses, FT-IR spectroscopy, powder X-ray diffraction (PXRD), thermogravimetric analyses as well as single-crystal X-ray diffraction analyses showing different dimensionalities (0D, 1D and 3D). Complexes 1 and 2 are 0D structures, 1 shows a dinuclear structure, 2 displays two crystallographically different mononuclear structures, 1 and 2 are further assembled to form 3D supramolecular framework and 2D supramolecular network by hydrogen-bonding interactions, respectively. Complexes 3, 4 and 5 are 1D structures, 3 features a mononuclear unit and a 1D chain, which are arranged into 3D supramolecular architecture by hydrogen-bonding interactions, 4 presents a zigzag chain, 5 shows an infinite chain structure constructed from pentanuclear Cu(II) subunits and ClO4- anions. Complex 6 exhibits a 3D coordination framework based on cyclic [Cu4(L3)2] dimmer subunits as nodes possessing an 8-connected network topology with the point symbol {424·64}. Further, semiconductor behaviors, the solid-state luminescent properties of the complexes 1-3 and 6 were measured and studied seriously at room temperature.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Scholbrock, A. K.; Fleming, P. A.; Fingersh, L. J.

Wind turbines are complex, nonlinear, dynamic systems driven by aerodynamic, gravitational, centrifugal, and gyroscopic forces. The aerodynamics of wind turbines are nonlinear, unsteady, and complex. Turbine rotors are subjected to a chaotic three-dimensional (3-D) turbulent wind inflow field with imbedded coherent vortices that drive fatigue loads and reduce lifetime. In order to reduce cost of energy, future large multimegawatt turbines must be designed with lighter weight structures, using active controls to mitigate fatigue loads, maximize energy capture, and add active damping to maintain stability for these dynamically active structures operating in a complex environment. Researchers at the National Renewable Energymore » Laboratory (NREL) and University of Stuttgart are designing, implementing, and testing advanced feed-back and feed-forward controls in order to reduce the cost of energy for wind turbines.« less

Cognitive Load and Attentional Demands during Objects' Position Change in Real and Digital Environments

ERIC Educational Resources Information Center

Zacharis, Georgios K.; Mikropoulos, Tassos Anastasios; Kalyvioti, Katerina

2016-01-01

Studies showed that two-dimensional (2D) and three-dimensional (3D) educational content contributes to learning. Although there were many studies with 3D stereoscopic learning environments, only a few studies reported on the differences between real, 2D, and 3D scenes, as far as cognitive load and attentional demands were concerned. We used…

Bim-Based Indoor Path Planning Considering Obstacles

NASA Astrophysics Data System (ADS)

Xu, M.; Wei, S.; Zlatanova, S.; Zhang, R.

2017-09-01

At present, 87 % of people's activities are in indoor environment; indoor navigation has become a research issue. As the building structures for people's daily life are more and more complex, many obstacles influence humans' moving. Therefore it is essential to provide an accurate and efficient indoor path planning. Nowadays there are many challenges and problems in indoor navigation. Most existing path planning approaches are based on 2D plans, pay more attention to the geometric configuration of indoor space, often ignore rich semantic information of building components, and mostly consider simple indoor layout without taking into account the furniture. Addressing the above shortcomings, this paper uses BIM (IFC) as the input data and concentrates on indoor navigation considering obstacles in the multi-floor buildings. After geometric and semantic information are extracted, 2D and 3D space subdivision methods are adopted to build the indoor navigation network and to realize a path planning that avoids obstacles. The 3D space subdivision is based on triangular prism. The two approaches are verified by the experiments.

Self-assembly of smallest magnetic particles

PubMed Central

Mehdizadeh Taheri, Sara; Michaelis, Maria; Friedrich, Thomas; Förster, Beate; Drechsler, Markus; Römer, Florian M.; Bösecke, Peter; Narayanan, Theyencheri; Weber, Birgit; Rehberg, Ingo; Rosenfeldt, Sabine; Förster, Stephan

2015-01-01

The assembly of tiny magnetic particles in external magnetic fields is important for many applications ranging from data storage to medical technologies. The development of ever smaller magnetic structures is restricted by a size limit, where the particles are just barely magnetic. For such particles we report the discovery of a kind of solution assembly hitherto unobserved, to our knowledge. The fact that the assembly occurs in solution is very relevant for applications, where magnetic nanoparticles are either solution-processed or are used in liquid biological environments. Induced by an external magnetic field, nanocubes spontaneously assemble into 1D chains, 2D monolayer sheets, and large 3D cuboids with almost perfect internal ordering. The self-assembly of the nanocubes can be elucidated considering the dipole–dipole interaction of small superparamagnetic particles. Complex 3D geometrical arrangements of the nanodipoles are obtained under the assumption that the orientation of magnetization is freely adjustable within the superlattice and tends to minimize the binding energy. On that basis the magnetic moment of the cuboids can be explained. PMID:26554000

Compact Q-balls in the complex signum-Gordon model

DOE Office of Scientific and Technical Information (OSTI.GOV)

Arodz, H.; Lis, J.

2008-05-15

We discuss Q-balls in the complex signum-Gordon model in d-dimensional space for d=1, 2, 3. The Q-balls have strictly finite size. Their total energy is a powerlike function of the conserved U(1) charge with the exponent equal to (d+2)(d+3){sup -1}. In the cases d=1 and d=3 explicit analytic solutions are presented.

Pediatric Multiple Sclerosis: Genes, Environment, and a Comprehensive Therapeutic Approach.

PubMed

Cappa, Ryan; Theroux, Liana; Brenton, J Nicholas

2017-10-01

Pediatric multiple sclerosis is an increasingly recognized and studied disorder that accounts for 3% to 10% of all patients with multiple sclerosis. The risk for pediatric multiple sclerosis is thought to reflect a complex interplay between environmental and genetic risk factors. Environmental exposures, including sunlight (ultraviolet radiation, vitamin D levels), infections (Epstein-Barr virus), passive smoking, and obesity, have been identified as potential risk factors in youth. Genetic predisposition contributes to the risk of multiple sclerosis, and the major histocompatibility complex on chromosome 6 makes the single largest contribution to susceptibility to multiple sclerosis. With the use of large-scale genome-wide association studies, other non-major histocompatibility complex alleles have been identified as independent risk factors for the disease. The bridge between environment and genes likely lies in the study of epigenetic processes, which are environmentally-influenced mechanisms through which gene expression may be modified. This article will review these topics to provide a framework for discussion of a comprehensive approach to counseling and ultimately treating the pediatric patient with multiple sclerosis. Copyright © 2017 Elsevier Inc. All rights reserved.

Comparing 2D and 3D Game-Based Learning Environments in Terms of Learning Gains and Student Perceptions

ERIC Educational Resources Information Center

Ak, Oguz; Kutlu, Birgul

2017-01-01

The aim of this study was to investigate the effectiveness of traditional, 2D and 3D game-based environments assessed by student achievement scores and to reveal student perceptions of the value of these learning environments. A total of 60 university students from the Faculty of Education who were registered in three sections of a required…

Geophysical techniques applied to urban planning in complex near surface environments. Examples of Zaragoza, NE Spain

NASA Astrophysics Data System (ADS)

Pueyo-Anchuela, Ó.; Casas-Sainz, A. M.; Soriano, M. A.; Pocoví-Juan, A.

Complex geological shallow subsurface environments represent an important handicap in urban and building projects. The geological features of the Central Ebro Basin, with sharp lateral changes in Quaternary deposits, alluvial karst phenomena and anthropic activity can preclude the characterization of future urban areas only from isolated geomechanical tests or from non-correctly dimensioned geophysical techniques. This complexity is here analyzed in two different test fields, (i) one of them linked to flat-bottomed valleys with irregular distribution of Quaternary deposits related to sharp lateral facies changes and irregular preconsolidated substratum position and (ii) a second one with similar complexities in the alluvial deposits and karst activity linked to solution of the underlying evaporite substratum. The results show that different geophysical techniques allow for similar geological models to be obtained in the first case (flat-bottomed valleys), whereas only the application of several geophysical techniques can permit to correctly evaluate the geological model complexities in the second case (alluvial karst). In this second case, the geological and superficial information permit to refine the sensitivity of the applied geophysical techniques to different indicators of karst activity. In both cases 3D models are needed to correctly distinguish alluvial lateral sedimentary changes from superimposed karstic activity.

Make it fun for everyone: visualization techniques in geoscience

NASA Astrophysics Data System (ADS)

Portnov, A.; Sojtaric, M.

2017-12-01

We live on a planet that mostly consists of oceans, but most people cannot picture what the surface and the subsurface of the ocean floor looks like. Marine geophysics has traditionally been difficult to explain to general public as most of what we do happens beyond the visual realm of an average audience. However, recent advances in 3D visualization of scientific data is one of the tools we can employ to better explain complex systems through gripping visual content. Coupled with a narrative approach, this type of visualization can open up a whole new and relatively little known world of science to general public. Up-to-date remote-sensing methods provide unique data of surface of seabed and subsurface all over the planet. Modern software can present this data in a spectacular way and with great scientific accuracy, making it attractive both for specialists and non-specialists in geoscience. As an example, we present several visualizations, which in simple way tell stories of various research in the remote parts of the World, such as Arctic regions and deep ocean in the Gulf of Mexico. Diverse datasets: multibeam echosounding; hydrographic survey; seismic and borehole data are put together to build up perfectly geo-referenced environment, showing the complexity of geological processes on our planet. Some of the data was collected 10-15 years ago, but acquired its new life with the help of new data visualization techniques. Every digital object with assigned coordinates, including 2D pictures and 3D models may become a part of this virtual geologic environment, limiting the potential of geo-visualization only by the imagination of a scientist. Presented videos have an apparent scientific focus on marine geology and geophysics, since the data was collected by several research and petroleum organizations, specialized in this field. The stories which we tell in this way may, for example, provide the public with further insight in complexities surrounding natural subsea gas storage and release.

Methodology for CFD Design Analysis of National Launch System Nozzle Manifold

NASA Technical Reports Server (NTRS)

Haire, Scot L.

1993-01-01

The current design environment dictates that high technology CFD (Computational Fluid Dynamics) analysis produce quality results in a timely manner if it is to be integrated into the design process. The design methodology outlined describes the CFD analysis of an NLS (National Launch System) nozzle film cooling manifold. The objective of the analysis was to obtain a qualitative estimate for the flow distribution within the manifold. A complex, 3D, multiple zone, structured grid was generated from a 3D CAD file of the geometry. A Euler solution was computed with a fully implicit compressible flow solver. Post processing consisted of full 3D color graphics and mass averaged performance. The result was a qualitative CFD solution that provided the design team with relevant information concerning the flow distribution in and performance characteristics of the film cooling manifold within an effective time frame. Also, this design methodology was the foundation for a quick turnaround CFD analysis of the next iteration in the manifold design.

Simulation of thermomechanical fatigue in solder joints

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fang, H.E.; Porter, V.L.; Fye, R.M.

1997-12-31

Thermomechanical fatigue (TMF) is a very complex phenomenon in electronic component systems and has been identified as one prominent degradation mechanism for surface mount solder joints in the stockpile. In order to precisely predict the TMF-related effects on the reliability of electronic components in weapons, a multi-level simulation methodology is being developed at Sandia National Laboratories. This methodology links simulation codes of continuum mechanics (JAS3D), microstructural mechanics (GLAD), and microstructural evolution (PARGRAIN) to treat the disparate length scales that exist between the macroscopic response of the component and the microstructural changes occurring in its constituent materials. JAS3D is used tomore » predict strain/temperature distributions in the component due to environmental variable fluctuations. GLAD identifies damage initiation and accumulation in detail based on the spatial information provided by JAS3D. PARGRAIN simulates the changes of material microstructure, such as the heterogeneous coarsening in Sn-Pb solder, when the component`s service environment varies.« less

Hdr Imaging for Feature Detection on Detailed Architectural Scenes

NASA Astrophysics Data System (ADS)

Kontogianni, G.; Stathopoulou, E. K.; Georgopoulos, A.; Doulamis, A.

2015-02-01

3D reconstruction relies on accurate detection, extraction, description and matching of image features. This is even truer for complex architectural scenes that pose needs for 3D models of high quality, without any loss of detail in geometry or color. Illumination conditions influence the radiometric quality of images, as standard sensors cannot depict properly a wide range of intensities in the same scene. Indeed, overexposed or underexposed pixels cause irreplaceable information loss and degrade digital representation. Images taken under extreme lighting environments may be thus prohibitive for feature detection/extraction and consequently for matching and 3D reconstruction. High Dynamic Range (HDR) images could be helpful for these operators because they broaden the limits of illumination range that Standard or Low Dynamic Range (SDR/LDR) images can capture and increase in this way the amount of details contained in the image. Experimental results of this study prove this assumption as they examine state of the art feature detectors applied both on standard dynamic range and HDR images.

Lead(II) coordination polymers based on rigid-flexible 3,5-bis-oxyacetate-benzoic acid: Structural transition driven by temperature control

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, Yong-Qiang, E-mail: chenjzxy@126.com; Tian, Yuan

2017-03-15

Three Pb(II) complexes ([Pb{sub 3}(BOABA){sub 2}(H{sub 2}O)]·H{sub 2}O){sub n} (1), ([Pb{sub 4}(BOABA){sub 2}(µ{sub 4}-O)(H{sub 2}O){sub 2}]·H{sub 2}O){sub n} (2), and [Pb{sub 3}(BOABA){sub 2}(H{sub 2}O)]{sub n} (3) (H{sub 3}BOABA=3,5-bis-oxyacetate-benzoic acid) were obtained under the same reaction systems with different temperatures. Complexes 1 and 2 are two dimensional (2D) networks based on Pb-BOABA chains and Pb{sub 4}(µ{sub 4}-O)(COO){sub 6} SBUs, respectively. Complex 3 presents an interesting three dimensional (3D) framework, was obtained by increasing the reaction temperature. Structural transition of the crystallization products is largely dependent on the reaction temperature. Moreover, the fluorescence properties of complexes 1–3 have been investigated. - Graphicalmore » abstract: Three Pb(II) coordination polymers were obtained under the same reaction systems with different temperatures. Both of complexes 1 and 2 are 2D network. 3 presents a 3D framework based on Pb–O–C rods SBUs. The 2D to 3D structures transition between three complexes was achieved successfully by temperature control. - Highlights: • Three Pb(II) complexes were obtained under the same reaction systems with different temperatures. • Structural transition of the crystallization products is largely dependent on the reaction temperature. • The luminescence properties studies reveal that three complexes exhibit yellow fluorescence emission behavior, which might be good candidates for obtaining photoluminescent materials.« less

A family of silver(I) complexes built with 2-sulfoterephthalic acid monosodium salt and different aminopyridine ligands: Syntheses, structures and properties

NASA Astrophysics Data System (ADS)

Zhang, Jie; Tan, Gai-Xiu; Liu, Bao-Lin; Dai, Yu-Bei; Xu, Na; Wen, Wei-Fen; Cao, Chong; Xiao, Hong-Ping

2017-05-01

Five Ag(I) coordination complexes, namely, [Ag6(2-stp)2(3-methyl-2-apy)3·H2O]n (1), [Ag3(2-stp)(4-methyl-2-apy)3]n (2), [Na2Ag18(2-stp)4(2-Hstp)4(5-methyl-2-apy)16 (H2O)4·11H2O]n (3), Ag3(2-stp)(6-methy-2-apy)4·H2O (4), and [Ag6(2-stp)2(6-methyl-2-apy)8(H2O)2·H2O]n (5) (2-NaH2stp = 2-sulfoterephthalic acid monosodium salt, 3-methyl-2-apy = 3-methyl-2-aminopyridine, 4-methyl-2-apy = 4-methyl-2-aminopyridine, 5-methyl-2-apy = 5-methyl-2-aminopyridine, 6-methyl-2-apy = 6-methyl-2-aminopyridine), have been synthesized and structurally characterized. Complexes 1 and 2 show two-dimensional network. In complex 3, the adjacent Ag10 units are bridged by 5-methyl-2-apy ligands to form a 2D infinite undulated sheet. Adjacent 2D sheets are linked by coordinative bonds between carboxylic oxygen atoms and Na(I) ions to form a 3D coordination polymer. Complex 4 is a 0-D discrete trinuclear molecule, and the self-complementary the Osbnd H⋯O and Nsbnd H⋯O hydrogen bonds incorporating hydrogen bond motifs extend these molecules into a 2D supramolecular framework. Compound 5 exhibits 1D-chain structure. However, complex 5 shows 3D supramolecular structure results from the linkage of neighboring layers through a rich hydrogen-bonding between uncoordinated sulfonates, amino groups and coordinated carboxylates. The thermogravimetric analyses and photoluminescence of the complexes were also investigated.

Syntheses, structures and luminescence of three copper(I) cyanide coordination polymers based on trigonal 1,3,5-tris(1H-imidazol-1-yl)benzene ligand

NASA Astrophysics Data System (ADS)

Shao, Min; Li, Ming-Xing; Lu, Li-Ruo; Zhang, Heng-Hua

2016-09-01

Three Cu(I)-cyanide coordination polymers based on trigonal 1,3,5-tris(1H-imidazol-1-yl)benzene (tib) ligand, namely [Cu3(CN)3(tib)]n (1), [Cu4(CN)4(tib)]n (2), and [Cu2(CN)2(tib)]n (3), have been prepared and characterized by elemental analysis, IR, PXRD, thermogravimetry and single-crystal X-ray diffraction analysis. Complex 1 displays a 3D metal-organic framework with nanosized pores. Complex 2 is a 3D coordination polymer assembled by three μ2-cyanides and a μ3-cyanide with a very short Cu(I)···Cu(I) metal bond(2.5206 Å). Complex 3 is a 2D coordination polymer constructing from 1D Cu(I)-cyanide zigzag chain and bidentate tib spacer. Three Cu(I) complexes are thermally stable up to 250-350 °C. Complexes 1-3 show similar orange emission band at 602 nm originating from LMCT mechanism.

Applications of Computer Technology in Complex Craniofacial Reconstruction.

PubMed

Day, Kristopher M; Gabrick, Kyle S; Sargent, Larry A

2018-03-01

To demonstrate our use of advanced 3-dimensional (3D) computer technology in the analysis, virtual surgical planning (VSP), 3D modeling (3DM), and treatment of complex congenital and acquired craniofacial deformities. We present a series of craniofacial defects treated at a tertiary craniofacial referral center utilizing state-of-the-art 3D computer technology. All patients treated at our center using computer-assisted VSP, prefabricated custom-designed 3DMs, and/or 3D printed custom implants (3DPCI) in the reconstruction of craniofacial defects were included in this analysis. We describe the use of 3D computer technology to precisely analyze, plan, and reconstruct 31 craniofacial deformities/syndromes caused by: Pierre-Robin (7), Treacher Collins (5), Apert's (2), Pfeiffer (2), Crouzon (1) Syndromes, craniosynostosis (6), hemifacial microsomia (2), micrognathia (2), multiple facial clefts (1), and trauma (3). In select cases where the available bone was insufficient for skeletal reconstruction, 3DPCIs were fabricated using 3D printing. We used VSP in 30, 3DMs in all 31, distraction osteogenesis in 16, and 3DPCIs in 13 cases. Utilizing these technologies, the above complex craniofacial defects were corrected without significant complications and with excellent aesthetic results. Modern 3D technology allows the surgeon to better analyze complex craniofacial deformities, precisely plan surgical correction with computer simulation of results, customize osteotomies, plan distractions, and print 3DPCI, as needed. The use of advanced 3D computer technology can be applied safely and potentially improve aesthetic and functional outcomes after complex craniofacial reconstruction. These techniques warrant further study and may be reproducible in various centers of care.

Life is 3D: Boosting Spheroid Function for Tissue Engineering.

PubMed

Laschke, Matthias W; Menger, Michael D

2017-02-01

Spheroids provide a 3D environment with intensive cell-cell contacts. As a result of their excellent regenerative properties and rapid progress in their high-throughput production, spheroids are increasingly suggested as building blocks for tissue engineering. In this review, we focus on innovative biotechnological approaches that increase the quality of spheroids for this specific type of application. These include in particular the fabrication of coculture spheroids, mimicking the complex morphology and physiological tasks of natural tissues. In vitro preconditioning under different culture conditions and incorporation of biomaterials improve the function of spheroids and their directed fusion into macrotissues of desired shapes. The continuous development of these sophisticated approaches may markedly contribute to a broad implementation of spheroid-based tissue engineering in future regenerative medicine. Copyright © 2016 Elsevier Ltd. All rights reserved.

Technology and application of 3D tunnel information monitoring

NASA Astrophysics Data System (ADS)

Li, Changqing; Deng, Hongliang; Chen, Ge; Wang, Simiao; Guo, Yang; Wu, Shenglin

2015-12-01

It is very necessary that Implement information monitoring and dynamic construction because of Complex geological environment and lack of basic information in the process of tunnel construction. The monitoring results show that 3 d laser scanning technology and information management system has important theoretical significance and application value to ensure the safety of tunnel construction, rich construction theory and technology. It can be known in real time the deformation information and the construction information in near tunnel workplace and the whole tunnel section in real time. In the meantime, it can be known the deformation regularity in the tunnel excavation process and the early warning and forecasting in the form of graphic and data. In order to determine the reasonable time and provide basis for supporting parameters and lining.

Digital microfabrication of user-defined 3D microstructures in cell-laden hydrogels.

PubMed

Soman, Pranav; Chung, Peter H; Zhang, A Ping; Chen, Shaochen

2013-11-01

Complex 3D interfacial arrangements of cells are found in several in vivo biosystems such as blood vasculature, renal glomeruli, and intestinal villi. Current tissue engineering techniques fail to develop suitable 3D microenvironments to evaluate the concurrent effects of complex topography and cell encapsulation. There is a need to develop new fabrication approaches that control cell density and distribution within complex 3D features. In this work, we present a dynamic projection printing process that allows rapid construction of complex 3D structures using custom-defined computer-aided-design (CAD) files. Gelatin-methacrylate (GelMA) constructs featuring user-defined spiral, pyramid, flower, and dome micro-geometries were fabricated with and without encapsulated cells. Encapsulated cells demonstrate good cell viability across all geometries both on the scaffold surface and internal to the structures. Cells respond to geometric cues individually as well as collectively throughout the larger-scale patterns. Time-lapse observations also reveal the dynamic nature of mechanical interactions between cells and micro-geometry. When compared to conventional cell-seeding, cell encapsulation within complex 3D patterned scaffolds provides long-term control over proliferation, cell morphology, and geometric guidance. Overall, this biofabrication technique offers a flexible platform to evaluate cell interactions with complex 3D micro-features, with the ability to scale-up towards high-throughput screening platforms. © 2013 Wiley Periodicals, Inc.

H3K9me3 demethylase Kdm4d facilitates the formation of pre-initiative complex and regulates DNA replication.

PubMed

Wu, Rentian; Wang, Zhiquan; Zhang, Honglian; Gan, Haiyun; Zhang, Zhiguo

2017-01-09

DNA replication is tightly regulated to occur once and only once per cell cycle. How chromatin, the physiological substrate of DNA replication machinery, regulates DNA replication remains largely unknown. Here we show that histone H3 lysine 9 demethylase Kdm4d regulates DNA replication in eukaryotic cells. Depletion of Kdm4d results in defects in DNA replication, which can be rescued by the expression of H3K9M, a histone H3 mutant transgene that reverses the effect of Kdm4d on H3K9 methylation. Kdm4d interacts with replication proteins, and its recruitment to DNA replication origins depends on the two pre-replicative complex components (origin recognition complex [ORC] and minichromosome maintenance [MCM] complex). Depletion of Kdm4d impairs the recruitment of Cdc45, proliferating cell nuclear antigen (PCNA), and polymerase δ, but not ORC and MCM proteins. These results demonstrate a novel mechanism by which Kdm4d regulates DNA replication by reducing the H3K9me3 level to facilitate formation of pre-initiative complex. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.

SAC3B, a central component of the mRNA export complex TREX-2, is required for prevention of epigenetic gene silencing in Arabidopsis

PubMed Central

Yang, Yu; La, Honggui; Tang, Kai; Miki, Daisuke; Yang, Lan; Wang, Bangshing; Duan, Cheng-Guo; Nie, Wenfeng; Wang, Xingang; Wang, Siwen; Pan, Yufeng; Tran, Elizabeth J.; An, Lizhe; Zhang, Huiming; Zhu, Jian-Kang

2017-01-01

Epigenetic regulation is important for organismal development and response to the environment. Alteration in epigenetic status has been known mostly from the perspective of enzymatic actions of DNA methylation and/or histone modifications. In a genetic screen for cellular factors involved in preventing epigenetic silencing, we isolated an Arabidopsis mutant defective in SAC3B, a component of the conserved TREX-2 complex that couples mRNA transcription with nuleo-cytoplasmic export. Arabidopsis SAC3B dysfunction causes gene silencing at transgenic and endogenous loci, accompanied by elevation in the repressive histone mark H3K9me2 and by reduction in RNA polymerase Pol II occupancy. SAC3B dysfunction does not alter promoter DNA methylation level of the transgene d35S::LUC, although the DNA demethylase ROS1 is also required for d35S::LUC anti-silencing. THP1 and NUA were identified as SAC3B-associated proteins whose mutations also caused d35S::LUC silencing. RNA-DNA hybrid exists at the repressed loci but is unrelated to gene suppression by the sac3b mutation. Genome-wide analyses demonstrated minor but clear involvement of SAC3B in regulating siRNAs and DNA methylation, particularly at a group of TAS and TAS-like loci. Together our results revealed not only a critical role of mRNA-export factors in transcriptional anti-silencing but also the contribution of SAC3B in shaping plant epigenetic landscapes. PMID:27672037

Infusion of a Gaming Paradigm into Computer-Aided Engineering Design Tools

DTIC Science & Technology

2012-05-03

Virtual Test Bed (VTB), and the gaming tool, Unity3D . This hybrid gaming environment coupled a three-dimensional (3D) multibody vehicle system model...from Google Earth to the 3D visual front-end fabricated around Unity3D . The hybrid environment was sufficiently developed to support analyses of the...ndFr Cti3r4 G’OjrdFr ctior-2 The VTB simulation of the vehicle dynamics ran concurrently with and interacted with the gaming engine, Unity3D which

Development of a Novel Motor Imagery Control Technique and Application in a Gaming Environment.

PubMed

Li, Ting; Zhang, Jinhua; Xue, Tao; Wang, Baozeng

2017-01-01

We present a methodology for a hybrid brain-computer interface (BCI) system, with the recognition of motor imagery (MI) based on EEG and blink EOG signals. We tested the BCI system in a 3D Tetris and an analogous 2D game playing environment. To enhance player's BCI control ability, the study focused on feature extraction from EEG and control strategy supporting Game-BCI system operation. We compared the numerical differences between spatial features extracted with common spatial pattern (CSP) and the proposed multifeature extraction. To demonstrate the effectiveness of 3D game environment at enhancing player's event-related desynchronization (ERD) and event-related synchronization (ERS) production ability, we set the 2D Screen Game as the comparison experiment. According to a series of statistical results, the group performing MI in the 3D Tetris environment showed more significant improvements in generating MI-associated ERD/ERS. Analysis results of game-score indicated that the players' scores presented an obvious uptrend in 3D Tetris environment but did not show an obvious downward trend in 2D Screen Game. It suggested that the immersive and rich-control environment for MI would improve the associated mental imagery and enhance MI-based BCI skills.

LiveView3D: Real Time Data Visualization for the Aerospace Testing Environment

NASA Technical Reports Server (NTRS)

Schwartz, Richard J.; Fleming, Gary A.

2006-01-01

This paper addresses LiveView3D, a software package and associated data visualization system for use in the aerospace testing environment. The LiveView3D system allows researchers to graphically view data from numerous wind tunnel instruments in real time in an interactive virtual environment. The graphical nature of the LiveView3D display provides researchers with an intuitive view of the measurement data, making it easier to interpret the aerodynamic phenomenon under investigation. LiveView3D has been developed at the NASA Langley Research Center and has been applied in the Langley Unitary Plan Wind Tunnel (UPWT). This paper discusses the capabilities of the LiveView3D system, provides example results from its application in the UPWT, and outlines features planned for future implementation.

Tetranuclear copper(II) complexes bridged by alpha-D-glucose-1-phosphate and incorporation of sugar acids through the Cu4 core structural changes.

PubMed

Kato, Merii; Sah, Ajay Kumar; Tanase, Tomoaki; Mikuriya, Masahiro

2006-08-21

Tetranuclear copper(II) complexes containing alpha-D-glucose-1-phosphate (alpha-D-Glc-1P), [Cu4(mu-OH){mu-(alpha-D-Glc-1P)}2(bpy)4(H2O)2]X3 [X = NO3 (1a), Cl (1b), Br (1c)], and [Cu4(mu-OH){mu-(alpha-D-Glc-1P)}2(phen)4(H2O)2](NO3)3 (2) were prepared by reacting the copper(II) salt with Na2[alpha-D-Glc-1P] in the presence of diimine ancillary ligands, and the structure of 2 was characterized by X-ray crystallography to comprise four {Cu(phen)}2+ fragments connected by the two sugar phosphate dianions in 1,3-O,O' and 1,1-O mu4-bridging fashion as well as a mu-hydroxo anion. The crystal structure of 2 involves two chemically independent complex cations in which the C2 enantiomeric structure for the trapezoidal tetracopper(II) framework is switched according to the orientation of the alpha-D-glucopyranosyl moieties. Temperature-dependent magnetic susceptibility data of 1a indicated that antiferromagnetic spin coupling is operative between the two metal ions joined by the hydroxo bridge (J = -52 cm(-1)) while antiferromagnetic interaction through the Cu-O-Cu sugar phosphate bridges is weak (J = -13 cm(-1)). Complex 1a readily reacted with carboxylic acids to afford the tetranuclear copper(II) complexes, [Cu4{mu-(alpha-D-Glc-1P)}2(mu-CA)2(bpy)4](NO3)2 [CA = CH3COO (3), o-C6H4(COO)(COOH) (4)]. Reactions with m-phenylenediacetic acid [m-C6H4(CH2COOH)2] also gave the discrete tetracopper(II) cationic complex [Cu4{mu-(alpha-D-Glc-1P)}2(mu-m-C6H4(CH2COO)(CH2COOH))2(bpy)4](NO3)2 (5a) as well as the cluster polymer formulated as {[Cu4{mu-(alpha-D-Glc-1P)}2(mu-m-C6H4(CH2COO)2)(bpy)4](NO3)2}n (5b). The tetracopper structure of 1a is converted into a symmetrical rectangular core in complexes 3, 4, and 5b, where the hydroxo bridge is dissociated and, instead, two carboxylate anions bridge another pair of Cu(II) ions in a 1,1-O monodentate fashion. The similar reactions were applied to incorporate sugar acids onto the tetranuclear copper(II) centers. Reactions of 1a with delta-D-gluconolactone, D-glucuronic acid, or D-glucaric acid in dimethylformamide resulted in the formation of discrete tetracopper complexes with sugar acids, [Cu4{mu-(alpha-D-Glc-1P)}2(mu-SA)2(bpy)4](NO3)2 [SA = D-gluconate (6), D-glucuronate (7), D-glucarateH (8a)]. The structures of 6 and 7 were determined by X-ray crystallography to be almost identical with that of 3 with additional chelating coordination of the C-2 hydroxyl group of D-gluconate moieties (6) or the C-5 cyclic O atom of D-glucuronate units (7). Those with D-glucaric acid and D-lactobionic acid afforded chiral one-dimensional polymers, {[Cu4{mu-(alpha-D-Glc-1P)}2(mu-D-glucarate)(bpy)4](NO3)2}n (8b) and {[Cu4{mu-(alpha-D-Glc-1P)}2(mu-D-lactobionate)(bpy)4(H2O)2](NO3)3}n (9), respectively, in which the D-Glc-1P-bridged tetracopper(II) units are connected by sugar acid moieties through the C-1 and C-6 carboxylate O atoms in 8b and the C-1 carboxylate and C-6 alkoxy O atoms of the gluconate chain in 9. When complex 7 containing d-glucuronate moieties was heated in water, the mononuclear copper(II) complex with 2-dihydroxy malonate, [Cu(mu-O2CC(OH)2CO2)(bpy)] (10), and the dicopper(II) complex with oxalate, [Cu2(mu-C2O4)(bpy)2(H2O)2](NO3)2 (11), were obtained as a result of oxidative degradation of the carbohydrates through C-C bond cleavage reactions.

Strategic Competition and Resistance in the 21st Century: Irregular, Catastrophic, Traditional, and Hybrid Challenges in Context

DTIC Science & Technology

2007-05-01

account for changes in the environment would ultimately limit American freedom of action and fundamentally jeopardize American great power. From the...reflect or account for this change in its strategic planning. DoD strategists further believed that the previous QDR, released in September 2001, did...commencement of work on NDS 05, the strategic environment proved more complex than previously articulated or accounted for by DoD. Suddenly the

A comparison of the accuracy of intraoral scanners using an intraoral environment simulator.

PubMed

Park, Hye-Nan; Lim, Young-Jun; Yi, Won-Jin; Han, Jung-Suk; Lee, Seung-Pyo

2018-02-01

The aim of this study was to design an intraoral environment simulator and to assess the accuracy of two intraoral scanners using the simulator. A box-shaped intraoral environment simulator was designed to simulate two specific intraoral environments. The cast was scanned 10 times by Identica Blue (MEDIT, Seoul, South Korea), TRIOS (3Shape, Copenhagen, Denmark), and CS3500 (Carestream Dental, Georgia, USA) scanners in the two simulated groups. The distances between the left and right canines (D3), first molars (D6), second molars (D7), and the left canine and left second molar (D37) were measured. The distance data were analyzed by the Kruskal-Wallis test. The differences in intraoral environments were not statistically significant ( P >.05). Between intraoral scanners, statistically significant differences ( P <.05) were revealed by the Kruskal-Wallis test with regard to D3 and D6. No difference due to the intraoral environment was revealed. The simulator will contribute to the higher accuracy of intraoral scanners in the future.

Construction, Structural Diversity and Properties of Five Coordination Polymers Based on 5-Nitroisophthalate and Bis(imidazole) Linkers

NASA Astrophysics Data System (ADS)

Arıcı, Mürsel

2018-06-01

Five coordination polymers, namely, [Cd(μ3-5-nip)(μ-obix)]n (1), [Co(μ3-5-nip)(μ-obix)]n (2), [Zn(μ-5-nip)(μ-obix)]n (3 and 4) and [Cd(μ-5-nip)(μ-bisobix)]n (5) (5-nip: 5-nitroisophthalate, obix: 1,2-bis(imidazol-1ylmethyl)benzene, bisobix: 1,2-bis(2-isopropylimidazol-1ylmethyl)benzene) were hydrothermally synthesized and characterized by IR spectroscopy, elemental analysis, single crystal and powder X-ray diffraction and thermal analysis (TG/DTA). X-ray results showed that the complexes displayed structural diversity depending on metal ions and conformations of bis(imidazole) linkers. Complexes 1 and 2 were 1D structures and obix ligand displayed cis-conformation. Complexes 3 and 4 exhibited 2D and 3D structures with same components depending on obix conformation. In complex 5, 3D+3D→3D interpenetrated structure was obtained with dia topology when bisobix having sterically hindered groups on imidazole rings was used. Moreover, thermal, photoluminescence and optical properties of the complexes were also investigated.

Recent advances in 3D printing of biomaterials.

PubMed

Chia, Helena N; Wu, Benjamin M

2015-01-01

3D Printing promises to produce complex biomedical devices according to computer design using patient-specific anatomical data. Since its initial use as pre-surgical visualization models and tooling molds, 3D Printing has slowly evolved to create one-of-a-kind devices, implants, scaffolds for tissue engineering, diagnostic platforms, and drug delivery systems. Fueled by the recent explosion in public interest and access to affordable printers, there is renewed interest to combine stem cells with custom 3D scaffolds for personalized regenerative medicine. Before 3D Printing can be used routinely for the regeneration of complex tissues (e.g. bone, cartilage, muscles, vessels, nerves in the craniomaxillofacial complex), and complex organs with intricate 3D microarchitecture (e.g. liver, lymphoid organs), several technological limitations must be addressed. In this review, the major materials and technology advances within the last five years for each of the common 3D Printing technologies (Three Dimensional Printing, Fused Deposition Modeling, Selective Laser Sintering, Stereolithography, and 3D Plotting/Direct-Write/Bioprinting) are described. Examples are highlighted to illustrate progress of each technology in tissue engineering, and key limitations are identified to motivate future research and advance this fascinating field of advanced manufacturing.

Creating Learning Environment Connecting Engineering Design and 3D Printing

NASA Astrophysics Data System (ADS)

Pikkarainen, Ari; Salminen, Antti; Piili, Heidi

Engineering education in modern days require continuous development in didactics, pedagogics and used practical methods. 3D printing provides excellent opportunity to connect different engineering areas into practice and produce learning by doing applications. The 3D-printing technology used in this study is FDM (Fused deposition modeling). FDM is the most used 3D-printing technology by commercial numbers at the moment and the qualities of the technology makes it popular especially in academic environments. For achieving the best result possible, students will incorporate the principles of DFAM (Design for additive manufacturing) into their engineering design studies together with 3D printing. This paper presents a plan for creating learning environment for mechanical engineering students combining the aspects of engineering design, 3D-CAD learning and AM (additive manufacturing). As a result, process charts for carrying out the 3D printing process from technological point of view and design process for AM from engineering design point of view were created. These charts are used in engineering design education. The learning environment is developed to work also as a platform for Bachelor theses, work-training environment for students, prototyping service centre for cooperation partners and source of information for mechanical engineering education in Lapland University of Applied Sciences.

Effects of Hurricane Surge Barrier on Hydraulic Environment, Jamaica Bay, New York; Hydraulic Model Investigation

DTIC Science & Technology

1976-09-01

the New York Harbor area and especially the Jamaica Bay complex was used to determine the effects of 13 different hurricane surge barrier plans on...vary directly with the total cross-sectional area of the naviga- tion opening and tidal openings. d. barrier plans B, C-l, C-2, and C-3 would have... plan C-1 with a conservative dye source seaward of the barrier indicated that average dye concentrations will be increased slightly in most areas in

A specification of 3D manipulation in virtual environments

NASA Technical Reports Server (NTRS)

Su, S. Augustine; Furuta, Richard

1994-01-01

In this paper we discuss the modeling of three basic kinds of 3-D manipulations in the context of a logical hand device and our virtual panel architecture. The logical hand device is a useful software abstraction representing hands in virtual environments. The virtual panel architecture is the 3-D component of the 2-D window systems. Both of the abstractions are intended to form the foundation for adaptable 3-D manipulation.

Panoramic 3D Reconstruction by Fusing Color Intensity and Laser Range Data

NASA Astrophysics Data System (ADS)

Jiang, Wei; Lu, Jian

Technology for capturing panoramic (360 degrees) three-dimensional information in a real environment have many applications in fields: virtual and complex reality, security, robot navigation, and so forth. In this study, we examine an acquisition device constructed of a regular CCD camera and a 2D laser range scanner, along with a technique for panoramic 3D reconstruction using a data fusion algorithm based on an energy minimization framework. The acquisition device can capture two types of data of a panoramic scene without occlusion between two sensors: a dense spatio-temporal volume from a camera and distance information from a laser scanner. We resample the dense spatio-temporal volume for generating a dense multi-perspective panorama that has equal spatial resolution to that of the original images acquired using a regular camera, and also estimate a dense panoramic depth-map corresponding to the generated reference panorama by extracting trajectories from the dense spatio-temporal volume with a selecting camera. Moreover, for determining distance information robustly, we propose a data fusion algorithm that is embedded into an energy minimization framework that incorporates active depth measurements using a 2D laser range scanner and passive geometry reconstruction from an image sequence obtained using the CCD camera. Thereby, measurement precision and robustness can be improved beyond those available by conventional methods using either passive geometry reconstruction (stereo vision) or a laser range scanner. Experimental results using both synthetic and actual images show that our approach can produce high-quality panoramas and perform accurate 3D reconstruction in a panoramic environment.

Longitudinal measurement of extracellular matrix rigidity in 3D tumor models using particle-tracking microrheology.

PubMed

Jones, Dustin P; Hanna, William; El-Hamidi, Hamid; Celli, Jonathan P

2014-06-10

The mechanical microenvironment has been shown to act as a crucial regulator of tumor growth behavior and signaling, which is itself remodeled and modified as part of a set of complex, two-way mechanosensitive interactions. While the development of biologically-relevant 3D tumor models have facilitated mechanistic studies on the impact of matrix rheology on tumor growth, the inverse problem of mapping changes in the mechanical environment induced by tumors remains challenging. Here, we describe the implementation of particle-tracking microrheology (PTM) in conjunction with 3D models of pancreatic cancer as part of a robust and viable approach for longitudinally monitoring physical changes in the tumor microenvironment, in situ. The methodology described here integrates a system of preparing in vitro 3D models embedded in a model extracellular matrix (ECM) scaffold of Type I collagen with fluorescently labeled probes uniformly distributed for position- and time-dependent microrheology measurements throughout the specimen. In vitro tumors are plated and probed in parallel conditions using multiwell imaging plates. Drawing on established methods, videos of tracer probe movements are transformed via the Generalized Stokes Einstein Relation (GSER) to report the complex frequency-dependent viscoelastic shear modulus, G*(ω). Because this approach is imaging-based, mechanical characterization is also mapped onto large transmitted-light spatial fields to simultaneously report qualitative changes in 3D tumor size and phenotype. Representative results showing contrasting mechanical response in sub-regions associated with localized invasion-induced matrix degradation as well as system calibration, validation data are presented. Undesirable outcomes from common experimental errors and troubleshooting of these issues are also presented. The 96-well 3D culture plating format implemented in this protocol is conducive to correlation of microrheology measurements with therapeutic screening assays or molecular imaging to gain new insights into impact of treatments or biochemical stimuli on the mechanical microenvironment.

Tissuelike 3D Assemblies of Human Broncho-Epithelial Cells

NASA Technical Reports Server (NTRS)

Goodwin, Thomas J.

2010-01-01

Three-dimensional (3D) tissuelike assemblies (TLAs) of human broncho-epithelial (HBE) cells have been developed for use in in vitro research on infection of humans by respiratory viruses. The 2D monolayer HBE cell cultures heretofore used in such research lack the complex cell structures and interactions characteristic of in vivo tissues and, consequently, do not adequately emulate the infection dynamics of in-vivo microbial adhesion and invasion. In contrast, the 3D HBE TLAs are characterized by more-realistic reproductions of the geometrical and functional complexity, differentiation of cells, cell-to-cell interactions, and cell-to-matrix interactions characteristic of human respiratory epithelia. Hence, the 3D HBE TLAs are expected to make it possible to perform at least some of the research in vitro under more-realistic conditions, without need to infect human subjects. The TLAs are grown on collagen-coated cyclodextran microbeads under controlled conditions in a nutrient liquid in the simulated microgravitational environment of a bioreactor of the rotating- wall-vessel type. Primary human mesenchymal bronchial-tracheal cells are used as a foundation matrix, while adult human bronchial epithelial immortalized cells are used as the overlying component. The beads become coated with cells, and cells on adjacent beads coalesce into 3D masses. The resulting TLAs have been found to share significant characteristics with in vivo human respiratory epithelia including polarization, tight junctions, desmosomes, and microvilli. The differentiation of the cells in these TLAs into tissues functionally similar to in vivo tissues is confirmed by the presence of compounds, including villin, keratins, and specific lung epithelium marker compounds, and by the production of tissue mucin. In a series of initial infection tests, TLA cultures were inoculated with human respiratory syncytial viruses and parainfluenza type 3 viruses. Infection was confirmed by photomicrographs that showed signs of damage by viruses and virus titers (see figure) that indicated large increases in the populations of viruses during the days following inoculation.

New approaches to high-resolution mapping of marine vertical structures.

PubMed

Robert, Katleen; Huvenne, Veerle A I; Georgiopoulou, Aggeliki; Jones, Daniel O B; Marsh, Leigh; D O Carter, Gareth; Chaumillon, Leo

2017-08-21

Vertical walls in marine environments can harbour high biodiversity and provide natural protection from bottom-trawling activities. However, traditional mapping techniques are usually restricted to down-looking approaches which cannot adequately replicate their 3D structure. We combined sideways-looking multibeam echosounder (MBES) data from an AUV, forward-looking MBES data from ROVs and ROV-acquired videos to examine walls from Rockall Bank and Whittard Canyon, Northeast Atlantic. High-resolution 3D point clouds were extracted from each sonar dataset and structure from motion photogrammetry (SfM) was applied to recreate 3D representations of video transects along the walls. With these reconstructions, it was possible to interact with extensive sections of video footage and precisely position individuals. Terrain variables were derived on scales comparable to those experienced by megabenthic individuals. These were used to show differences in environmental conditions between observed and background locations as well as explain spatial patterns in ecological characteristics. In addition, since the SfM 3D reconstructions retained colours, they were employed to separate and quantify live coral colonies versus dead framework. The combination of these new technologies allows us, for the first time, to map the physical 3D structure of previously inaccessible habitats and demonstrates the complexity and importance of vertical structures.

Fluid flow increases mineralized matrix deposition in 3D perfusion culture of marrow stromal osteoblasts in a dose-dependent manner

NASA Technical Reports Server (NTRS)

Bancroft, Gregory N.; Sikavitsas, Vassilios I.; van den Dolder, Juliette; Sheffield, Tiffany L.; Ambrose, Catherine G.; Jansen, John A.; Mikos, Antonios G.; McIntire, L. V. (Principal Investigator)

2002-01-01

Bone is a complex highly structured mechanically active 3D tissue composed of cellular and matrix elements. The true biological environment of a bone cell is thus derived from a dynamic interaction between responsively active cells experiencing mechanical forces and a continuously changing 3D matrix architecture. To investigate this phenomenon in vitro, marrow stromal osteoblasts were cultured on 3D scaffolds under flow perfusion with different rates of flow for an extended period to permit osteoblast differentiation and significant matrix production and mineralization. With all flow conditions, mineralized matrix production was dramatically increased over statically cultured constructs with the total calcium content of the cultured scaffolds increasing with increasing flow rate. Flow perfusion induced de novo tissue modeling with the formation of pore-like structures in the scaffolds and enhanced the distribution of cells and matrix throughout the scaffolds. These results represent reporting of the long-term effects of fluid flow on primary differentiating osteoblasts and indicate that fluid flow has far-reaching effects on osteoblast differentiation and phenotypic expression in vitro. Flow perfusion culture permits the generation and study of a 3D, actively modeled, mineralized matrix and can therefore be a valuable tool for both bone biology and tissue engineering.

Embedded Multimaterial Extrusion Bioprinting.

PubMed

Rocca, Marco; Fragasso, Alessio; Liu, Wanjun; Heinrich, Marcel A; Zhang, Yu Shrike

2018-04-01

Embedded extrusion bioprinting allows for the generation of complex structures that otherwise cannot be achieved with conventional layer-by-layer deposition from the bottom, by overcoming the limits imposed by gravitational force. By taking advantage of a hydrogel bath, serving as a sacrificial printing environment, it is feasible to extrude a bioink in freeform until the entire structure is deposited and crosslinked. The bioprinted structure can be subsequently released from the supporting hydrogel and used for further applications. Combining this advanced three-dimensional (3D) bioprinting technique with a multimaterial extrusion printhead setup enables the fabrication of complex volumetric structures built from multiple bioinks. The work described in this paper focuses on the optimization of the experimental setup and proposes a workflow to automate the bioprinting process, resulting in a fast and efficient conversion of a virtual 3D model into a physical, extruded structure in freeform using the multimaterial embedded bioprinting system. It is anticipated that further development of this technology will likely lead to widespread applications in areas such as tissue engineering, pharmaceutical testing, and organs-on-chips.

The Efficacy of an Immersive 3D Virtual versus 2D Web Environment in Intercultural Sensitivity Acquisition

ERIC Educational Resources Information Center

Coffey, Amy Jo; Kamhawi, Rasha; Fishwick, Paul; Henderson, Julie

2017-01-01

Relatively few studies have empirically tested computer-based immersive virtual environments' efficacy in teaching or enhancing pro-social attitudes, such as intercultural sensitivity. This channel study experiment was conducted (N = 159) to compare what effects, if any, an immersive 3D virtual environment would have upon subjects' intercultural…

Structure and catalytic activities of ferrous centers confined on the interface between carbon nanotubes and humic acid

NASA Astrophysics Data System (ADS)

Wang, Bing; Zhou, Xiaoyan; Wang, Dongqi; Yin, Jun-Jie; Chen, Hanqing; Gao, Xingfa; Zhang, Jing; Ibrahim, Kurash; Chai, Zhifang; Feng, Weiyue; Zhao, Yuliang

2015-01-01

Preparation of heterogeneous catalysts with active ferrous centers is of great significance for industrial and environmental catalytic processes. Nanostructured carbon materials (NCM), which possess free-flowing π electrons, can coordinate with transition metals, provide a confinement environment for catalysis, and act as potential supports or ligands to construct analogous complexes. However, designing such catalysts using NCM is still seldom studied to date. Herein, we synthesized a sandwich structured ternary complex via the coordination of Fe-loaded humic acid (HA) with C&z.dbd;C bonds in the aromatic rings of carbon nanotubes (CNTs), in which the O/N-Fe-C interface configuration provides the confinement environment for the ferrous sites. The experimental and theoretical results revealed octahedrally/tetrahedrally coordinated geometry at Fe centers, and the strong hybridization between CNT C π* and Fe 3d orbitals induces discretization of the atomic charges on aromatic rings of CNTs, which facilitates O2 adsorption and electron transfer from carbon to O2, which enhances O2 activation. The O2 activation by the novel HA/Fe-CNT complex can be applied in the oxidative degradation of phenol red (PR) and bisphenol A (BPA) in aqueous media.Preparation of heterogeneous catalysts with active ferrous centers is of great significance for industrial and environmental catalytic processes. Nanostructured carbon materials (NCM), which possess free-flowing π electrons, can coordinate with transition metals, provide a confinement environment for catalysis, and act as potential supports or ligands to construct analogous complexes. However, designing such catalysts using NCM is still seldom studied to date. Herein, we synthesized a sandwich structured ternary complex via the coordination of Fe-loaded humic acid (HA) with C&z.dbd;C bonds in the aromatic rings of carbon nanotubes (CNTs), in which the O/N-Fe-C interface configuration provides the confinement environment for the ferrous sites. The experimental and theoretical results revealed octahedrally/tetrahedrally coordinated geometry at Fe centers, and the strong hybridization between CNT C π* and Fe 3d orbitals induces discretization of the atomic charges on aromatic rings of CNTs, which facilitates O2 adsorption and electron transfer from carbon to O2, which enhances O2 activation. The O2 activation by the novel HA/Fe-CNT complex can be applied in the oxidative degradation of phenol red (PR) and bisphenol A (BPA) in aqueous media. Electronic supplementary information (ESI) available: Optimization of the mass ratios of HA to CNTs and the reaction pH conditions for Fe loading; scanning electron microscope (SEM), UV-Vis-near-infrared, Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR) for CNT-HA; EPR experiment and UPLC-ESI-MS analysis; and DFT calculation. See DOI: 10.1039/c4nr06665k

Quadcopter control in three-dimensional space using a noninvasive motor imagery-based brain-computer interface

NASA Astrophysics Data System (ADS)

LaFleur, Karl; Cassady, Kaitlin; Doud, Alexander; Shades, Kaleb; Rogin, Eitan; He, Bin

2013-08-01

Objective. At the balanced intersection of human and machine adaptation is found the optimally functioning brain-computer interface (BCI). In this study, we report a novel experiment of BCI controlling a robotic quadcopter in three-dimensional (3D) physical space using noninvasive scalp electroencephalogram (EEG) in human subjects. We then quantify the performance of this system using metrics suitable for asynchronous BCI. Lastly, we examine the impact that the operation of a real world device has on subjects' control in comparison to a 2D virtual cursor task. Approach. Five human subjects were trained to modulate their sensorimotor rhythms to control an AR Drone navigating a 3D physical space. Visual feedback was provided via a forward facing camera on the hull of the drone. Main results. Individual subjects were able to accurately acquire up to 90.5% of all valid targets presented while travelling at an average straight-line speed of 0.69 m s-1. Significance. Freely exploring and interacting with the world around us is a crucial element of autonomy that is lost in the context of neurodegenerative disease. Brain-computer interfaces are systems that aim to restore or enhance a user's ability to interact with the environment via a computer and through the use of only thought. We demonstrate for the first time the ability to control a flying robot in 3D physical space using noninvasive scalp recorded EEG in humans. Our work indicates the potential of noninvasive EEG-based BCI systems for accomplish complex control in 3D physical space. The present study may serve as a framework for the investigation of multidimensional noninvasive BCI control in a physical environment using telepresence robotics.

Quadcopter control in three-dimensional space using a noninvasive motor imagery-based brain-computer interface.

PubMed

LaFleur, Karl; Cassady, Kaitlin; Doud, Alexander; Shades, Kaleb; Rogin, Eitan; He, Bin

2013-08-01

At the balanced intersection of human and machine adaptation is found the optimally functioning brain-computer interface (BCI). In this study, we report a novel experiment of BCI controlling a robotic quadcopter in three-dimensional (3D) physical space using noninvasive scalp electroencephalogram (EEG) in human subjects. We then quantify the performance of this system using metrics suitable for asynchronous BCI. Lastly, we examine the impact that the operation of a real world device has on subjects' control in comparison to a 2D virtual cursor task. Five human subjects were trained to modulate their sensorimotor rhythms to control an AR Drone navigating a 3D physical space. Visual feedback was provided via a forward facing camera on the hull of the drone. Individual subjects were able to accurately acquire up to 90.5% of all valid targets presented while travelling at an average straight-line speed of 0.69 m s(-1). Freely exploring and interacting with the world around us is a crucial element of autonomy that is lost in the context of neurodegenerative disease. Brain-computer interfaces are systems that aim to restore or enhance a user's ability to interact with the environment via a computer and through the use of only thought. We demonstrate for the first time the ability to control a flying robot in 3D physical space using noninvasive scalp recorded EEG in humans. Our work indicates the potential of noninvasive EEG-based BCI systems for accomplish complex control in 3D physical space. The present study may serve as a framework for the investigation of multidimensional noninvasive BCI control in a physical environment using telepresence robotics.

Team Creative Environment as a Mediator Between CWX and R&D Team Performance and Moderating Boundary Conditions.

PubMed

Bornay-Barrachina, Mar; Herrero, Inés

2018-01-01

The purpose of this study was to investigate how high-quality dyadic co-worker relationships (CWXs) favour or hinder team performance. Specifically, we examine the role played by CWX, team creative environment, job complexity and task interdependence to achieve higher levels of team performance. We analyse data from 410 individuals belonging to 81 R&D teams in technology sciences to examine the quality of the dyadic relationships between team members under the same supervisor (co-workers) and team performance measured by the number of publications as their research output. Higher levels of team average CWX relationships are positively related to the establishment of a favourable creative team environment, ending into higher levels of team performance. Specifically, the role played by team average CWX in such relationship is stronger when job complexity and task interdependence are also high. Team's output not only depends on the leader and his/her relationships with subordinates but also on quality relationships among team members. CWXs contribute to creative team environments, but they are essential where jobs are complex and tasks are highly dependent. This study provides evidence of the important role played by CWXs in determining a creative environment, irrespective of their leaders. Previous research has provided information about how leader's role affects team outcomes, but the role of dyadic co-worker relationships in a team remains still relatively unknown. Considering job complexity and task interdependence variables, the study provides with a better understanding about how and when high-quality CWXs should be promoted to achieve higher team performance.

3D imaging and quantitative analysis of small solubilized membrane proteins and their complexes by transmission electron microscopy

PubMed Central

Vahedi-Faridi, Ardeschir; Jastrzebska, Beata; Palczewski, Krzysztof; Engel, Andreas

2013-01-01

Inherently unstable, detergent-solubilized membrane protein complexes can often not be crystallized. For complexes that have a mass of >300 kDa, cryo-electron microscopy (EM) allows their three-dimensional (3D) structure to be assessed to a resolution that makes secondary structure elements visible in the best case. However, many interesting complexes exist whose mass is below 300 kDa and thus need alternative approaches. Two methods are reviewed: (i) Mass measurement in a scanning transmission electron microscope, which has provided important information on the stoichiometry of membrane protein complexes. This technique is applicable to particulate, filamentous and sheet-like structures. (ii) 3D-EM of negatively stained samples, which determines the molecular envelope of small membrane protein complexes. Staining and dehydration artifacts may corrupt the quality of the 3D map. Staining conditions thus need to be optimized. 3D maps of plant aquaporin SoPIP2;1 tetramers solubilized in different detergents illustrate that the flattening artifact can be partially prevented and that the detergent itself contributes significantly. Another example discussed is the complex of G protein-coupled receptor rhodopsin with its cognate G protein transducin. PMID:23267047

BINDING OF SOLUBLE IMMUNE COMPLEXES TO HUMAN LYMPHOBLASTOID CELLS

PubMed Central

Theofilopoulos, Argyrios N.; Dixon, Frank J.; Bokisch, Viktor A.

1974-01-01

In the present work we studied the expression of membrane-bound Ig (MBIg) as well as receptors for IgG Fc and complement on nine human lymphoblastoid cell lines. When MBIg and receptors for IgG Fc were compared, four categories of cell lines could be distinguished: (a) cell lines having both MBIg and receptors for IgG Fc, (b) cell lines having MBIg but lacking receptors for IgG Fc, (c) cell lines lacking MBIg but having receptors for IgG Fc, and (d) cell lines lacking both MBIg and receptors for IgG Fc. Two types of receptors for complement could be detected on the cell lines studied, one for C3-C3b and one for C3d. When sensitized red cells carrying C3b or C3d were used for rosette tests, three categories of cell lines could be distinguished: (a) cell lines having receptors for C3b and C3d, (b) cell lines having receptors only for C3d and (c) cell lines lacking both receptors. However, when a more sensitive immunofluorescent method was used instead of the rosette technique, it was found that cell lines unable to form rosettes with EAC1423bhu were able to bind soluble C3 or C3b which indicated the presence of these receptors on the cell surface. Inhibition experiments showed that receptors for C3-C3b and receptors for C3d are distinct and that receptors for C3-C3b and C3d are different from receptors for IgG Fc. A cell line (Raji) without MBIg but with receptors for IgG Fc, C3-C3b, and C3d was selected for use in studying the binding mechanism of soluble immune complexes to cell surface membrane. Aggregated human gamma globulin was used in place of immune complexes. Immune complexes containing complement bind to Raji cells only via receptors for complement, namely receptors for C3-C3b and C3d. Binding of immune complexes containing complement to cells is much greater than that of complexes without complement. Immune complexes bound to cells via receptors for complement can be partially released from the cell surface by addition of normal human serum as well as isolated human C3 or C3b. We postulate that such release is due to competition of immune complex bound C3b and free C3 or C3b for the receptors on Raji cells. PMID:4139225

Going Virtual… or Not: Development and Testing of a 3D Virtual Astronomy Environment

NASA Astrophysics Data System (ADS)

Ruzhitskaya, L.; Speck, A.; Ding, N.; Baldridge, S.; Witzig, S.; Laffey, J.

2013-04-01

We present our preliminary results of a pilot study of students' knowledge transfer of an astronomy concept into a new environment. We also share our discoveries on what aspects of a 3D environment students consider being motivational and discouraging for their learning. This study was conducted among 64 non-science major students enrolled in an astronomy laboratory course. During the course, students learned the concept and applications of Kepler's laws using a 2D interactive environment. Later in the semester, the students were placed in a 3D environment in which they were asked to conduct observations and to answers a set of questions pertaining to the Kepler's laws of planetary motion. In this study, we were interested in observing scrutinizing and assessing students' behavior: from choices that they made while creating their avatars (virtual representations) to tools they choose to use, to their navigational patterns, to their levels of discourse in the environment. These helped us to identify what features of the 3D environment our participants found to be helpful and interesting and what tools created unnecessary clutter and distraction. The students' social behavior patterns in the virtual environment together with their answers to the questions helped us to determine how well they understood Kepler's laws, how well they could transfer the concepts to a new situation, and at what point a motivational tool such as a 3D environment becomes a disruption to the constructive learning. Our founding confirmed that students construct deeper knowledge of a concept when they are fully immersed in the environment.

3D bioprinting of tissues and organs.

PubMed

Murphy, Sean V; Atala, Anthony

2014-08-01

Additive manufacturing, otherwise known as three-dimensional (3D) printing, is driving major innovations in many areas, such as engineering, manufacturing, art, education and medicine. Recent advances have enabled 3D printing of biocompatible materials, cells and supporting components into complex 3D functional living tissues. 3D bioprinting is being applied to regenerative medicine to address the need for tissues and organs suitable for transplantation. Compared with non-biological printing, 3D bioprinting involves additional complexities, such as the choice of materials, cell types, growth and differentiation factors, and technical challenges related to the sensitivities of living cells and the construction of tissues. Addressing these complexities requires the integration of technologies from the fields of engineering, biomaterials science, cell biology, physics and medicine. 3D bioprinting has already been used for the generation and transplantation of several tissues, including multilayered skin, bone, vascular grafts, tracheal splints, heart tissue and cartilaginous structures. Other applications include developing high-throughput 3D-bioprinted tissue models for research, drug discovery and toxicology.

Sequence design and software environment for real-time navigation of a wireless ferromagnetic device using MRI system and single echo 3D tracking.

PubMed

Chanu, A; Aboussouan, E; Tamaz, S; Martel, S

2006-01-01

Software architecture for the navigation of a ferromagnetic untethered device in a 1D and 2D phantom environment is briefly described. Navigation is achieved using the real-time capabilities of a Siemens 1.5 T Avanto MRI system coupled with a dedicated software environment and a specially developed 3D tracking pulse sequence. Real-time control of the magnetic core is executed through the implementation of a simple PID controller. 1D and 2D experimental results are presented.

Urban Typologies: Towards an ORNL Urban Information System (UrbIS)

NASA Astrophysics Data System (ADS)

KC, B.; King, A. W.; Sorokine, A.; Crow, M. C.; Devarakonda, R.; Hilbert, N. L.; Karthik, R.; Patlolla, D.; Surendran Nair, S.

2016-12-01

Urban environments differ in a large number of key attributes; these include infrastructure, morphology, demography, and economic and social variables, among others. These attributes determine many urban properties such as energy and water consumption, greenhouse gas emissions, air quality, public health, sustainability, and vulnerability and resilience to climate change. Characterization of urban environments by a single property such as population size does not sufficiently capture this complexity. In addressing this multivariate complexity one typically faces such problems as disparate and scattered data, challenges of big data management, spatial searching, insufficient computational capacity for data-driven analysis and modelling, and the lack of tools to quickly visualize the data and compare the analytical results across different cities and regions. We have begun the development of an Urban Information System (UrbIS) to address these issues, one that embraces the multivariate "big data" of urban areas and their environments across the United States utilizing the Big Data as a Service (BDaaS) concept. With technological roots in High-performance Computing (HPC), BDaaS is based on the idea of outsourcing computations to different computing paradigms, scalable to super-computers. UrbIS aims to incorporate federated metadata search, integrated modeling and analysis, and geovisualization into a single seamless workflow. The system includes web-based 2D/3D visualization with an iGlobe interface, fast cloud-based and server-side data processing and analysis, and a metadata search engine based on the Mercury data search system developed at Oak Ridge National Laboratory (ORNL). Results of analyses will be made available through web services. We are implementing UrbIS in ORNL's Compute and Data Environment for Science (CADES) and are leveraging ORNL experience in complex data and geospatial projects. The development of UrbIS is being guided by an investigation of urban heat islands (UHI) using high-dimensional clustering and statistics to define urban typologies (types of cities) in an investigation of how UHI vary with urban type across the United States.

Influence of topographic complexity on solar insolation estimates for the Colorado River, Grand Canyon, AZ

USGS Publications Warehouse

Yard, M.D.; Bennett, G.E.; Mietz, S.N.; Coggins, L.G.; Stevens, L.E.; Hueftle, S.; Blinn, D.W.

2005-01-01

Rugged topography along the Colorado River in Glen and Grand Canyons, exemplifies features common to canyon-bound streams and rivers of the arid southwest. Physical relief influences regulated river systems, especially those that are altered, and have become partially reliant on aquatic primary production. We measured and modeled instantaneous solar flux in a topographically complex environment to determine where differences in daily, seasonal and annual solar insolation occurred in this river system. At a system-wide scale, topographic complexity generates a spatial and temporal mosaic of varying solar insolation. This solar variation is a predictable consequence of channel orientation, geomorphology, elevation angles and viewshed. Modeled estimates for clear conditions corresponded closely with observed measurements for both instantaneous photosynthetic photon flux density (PPFD: ??mol m-2 s-1) and daily insolation levels (relative error 2.3%, CI ??0.45, S.D. 0.3, n = 29,813). Mean annual daily insolation levels system-wide were estimated to be 36 mol m-2 d -1 (17.5 S.D.), and seasonally varied on average from 13.4-57.4 mol m-2 d-1, for winter and summer, respectively. In comparison to identical areas lacking topographic effect (idealized plane), mean daily insolation levels were reduced by 22% during summer, and as much as 53% during winter. Depending on outlying topography, canyon bound regions having east-west (EW) orientations had higher seasonal variation, averaging from 8.1 to 61.4 mol m-2 d-1, for winter and summer, respectively. For EW orientations, 70% of mid-channel sites were obscured from direct incidence during part of the year; and of these sites, average diffuse light conditions persisted for 19.3% of the year (70.5 days), and extended upwards to 194 days. This predictive model has provided an initial quantitative step to estimate and determine the importance of autotrophic production for this ecosystem, as well as a broader application for other canyon systems. ?? 2004 Published by Elsevier B.V.

Applying a 3D Situational Virtual Learning Environment to the Real World Business--An Extended Research in Marketing

ERIC Educational Resources Information Center

Wang, Shwu-huey

2012-01-01

In order to understand (1) what kind of students can be facilitated through the help of three-dimensional virtual learning environment (3D VLE), and (2) the relationship between a conventional test (ie, paper and pencil test) and the 3D VLE used in this study, the study designs a 3D virtual supermarket (3DVS) to help students transform their role…

The physical model for research of behavior of grouting mixtures

NASA Astrophysics Data System (ADS)

Hajovsky, Radovan; Pies, Martin; Lossmann, Jaroslav

2016-06-01

The paper deals with description of physical model designed for verification of behavior of grouting mixtures when applied below underground water level. Described physical model has been set up to determine propagation of grouting mixture in a given environment. Extension of grouting in this environment is based on measurement of humidity and temperature with the use of combined sensors located within preinstalled special measurement probes around grouting needle. Humidity was measured by combined capacity sensor DTH-1010, temperature was gathered by a NTC thermistor. Humidity sensors measured time when grouting mixture reached sensor location point. NTC thermistors measured temperature changes in time starting from initial of injection. This helped to develop 3D map showing the distribution of grouting mixture through the environment. Accomplishment of this particular measurement was carried out by a designed primary measurement module capable of connecting 4 humidity and temperature sensors. This module also takes care of converting these physical signals into unified analogue signals consequently brought to the input terminals of analogue input of programmable automation controller (PAC) WinPAC-8441. This controller ensures the measurement itself, archiving and visualization of all data. Detail description of a complex measurement system and evaluation in form of 3D animations and graphs is supposed to be in a full paper.

Generic Dynamic Environment Perception Using Smart Mobile Devices.

PubMed

Danescu, Radu; Itu, Razvan; Petrovai, Andra

2016-10-17

The driving environment is complex and dynamic, and the attention of the driver is continuously challenged, therefore computer based assistance achieved by processing image and sensor data may increase traffic safety. While active sensors and stereovision have the advantage of obtaining 3D data directly, monocular vision is easy to set up, and can benefit from the increasing computational power of smart mobile devices, and from the fact that almost all of them come with an embedded camera. Several driving assistance application are available for mobile devices, but they are mostly targeted for simple scenarios and a limited range of obstacle shapes and poses. This paper presents a technique for generic, shape independent real-time obstacle detection for mobile devices, based on a dynamic, free form 3D representation of the environment: the particle based occupancy grid. Images acquired in real time from the smart mobile device's camera are processed by removing the perspective effect and segmenting the resulted bird-eye view image to identify candidate obstacle areas, which are then used to update the occupancy grid. The occupancy grid tracked cells are grouped into obstacles depicted as cuboids having position, size, orientation and speed. The easy to set up system is able to reliably detect most obstacles in urban traffic, and its measurement accuracy is comparable to a stereovision system.

A series of transition metal-organic frameworks based on a bipyridinium carboxylate ligand: Syntheses, structures and photoluminescent properties

NASA Astrophysics Data System (ADS)

Pei, Ru-Bo; Cao, Ming-Yang; Li, Lin-Ke; Dong, Xi-Yan; Zang, Shuang-Quan

2017-09-01

Based on a bipyridinium carboxylate ligand 1-(3,5-dicarboxy)-benzyl-1,2-di(pyridine-4-yl)ethylene chloride (H2L+Cl-), eight transition metal coordination polymers, namely, {[Zn(L)Cl]ṡ4H2O}n (1), {[Zn(L)H2O]ṡNO3ṡ2H2O}n (2), {[Zn(L) (H2O)]ṡ(NO3)0.5ṡ(Cl)0.5ṡ2H2O}n (3), {[Cd(L)(H2O)(NO3)]ṡ2H2O}n (4), {[Cd1.5(L) (Cl)2]ṡ2H2O}n (5), {[Cu(L)(H2O)]ṡNO3ṡH2O}n (6), {[Cu(HL)2(H2O)2]·Cl2·6H2O}n (7) and {[Ni(L)(H2O)Cl]ṡ4H2O}n (8) have been synthesized and characterized by single-crystal X-ray diffraction analyses. Complexes 1 and 8 display 2D wave-like layer structures with a 3-connected 63 topology. Complexes 2 and 6 demonstrate 3D 2-fold interpenetrating frameworks with uninodal, 3-connected (10,3)-d utp-topology. Another pair of 3D 2-fold interpenetrating frameworks 3 and 4 possess 3-connected, uninodal 103ThSi2 (ths)-topology. Complex 5 shows a 2D layer structure based on the extending of trinuclear Cd(II) subunits. Complex 7 presents 1D double-chain structure, in which the central Cu(II) ions are connected by the partially deprotonated ligand HL. Additionally, powder X-ray diffractions (PXRD) and thermogravimetric analyses of complexes 1-8, as well as the solid-state luminescent properties of d10 metal complexes 1-4 at room temperature have also been discussed.

Ferromagnetic interactions in Ru(III)-nitronyl nitroxide radical complex: a potential 2p4d building block for molecular magnets.

PubMed

Pointillart, Fabrice; Bernot, Kevin; Sorace, Lorenzo; Sessoli, Roberta; Gatteschi, Dante

2007-07-07

The reaction between [Ru(salen)(PPh3)Cl] and the 4-pyridyl-substituted nitronyl nitroxide radical (NITpPy) leads to the [Ru(salen)(PPh3)(NITpPy)](ClO4)(H2O)2 complex while the reaction with the azido anion (N3-) leads to the [Ru(salen)(PPh3)(N3)] complex 2 (where salen2- = N,N'-ethan-1,2-diylbis(salicylidenamine) and PPh3 = triphenylphosphine). Both compounds have been characterized by single crystal X-ray diffraction. The two crystal structures are composed by a [Ru(III)(salen)(PPh3)]+ unit where the Ru(III) ion is coordinated to a salen2- ligand and one PPh3 ligand in axial position. In 1 the Ru(III) ion is coordinated to the 4-pyridyl-substituted nitronyl nitroxide radical whereas in 2 the second axial position is occupied by the azido ligand. In both complexes the Ru(III) ions are in the same environment RuO2N3P, in a tetragonally elongated octhaedral geometry. The crystal packing of 1 reveals pi-stacking in pairs. While antiferromagnetic intermolecular interaction (J2 = 5.0 cm(-1)) dominates at low temperatures, ferromagnetic intramolecular interaction (J1 = -9.0 cm(-1)) have been found between the Ru(III) ion and the coordinated NITpPy.

Signal and Noise in 3D Environments

DTIC Science & Technology

2015-09-30

complicated 3D environments. I have also been doing a great deal of work in modeling the noise field (the ocean soundscape ) due to various sources... soundscape to learn about the ocean environment. I distinguish this from geoacoustic inversion and ocean tomography, in that the methods envisioned will rely...on broader features of the soundscape . OBJECTIVES In the first phase of this effort we will focus on the 3D modeling solutions, documenting the

Mathematical 3D modelling and sensitivity analysis of multipolar radiofrequency ablation in the spine.

PubMed

Matschek, Janine; Bullinger, Eric; von Haeseler, Friedrich; Skalej, Martin; Findeisen, Rolf

2017-02-01

Radiofrequency ablation is a valuable tool in the treatment of many diseases, especially cancer. However, controlled heating up to apoptosis of the desired target tissue in complex situations, e.g. in the spine, is challenging and requires experienced interventionalists. For such challenging situations a mathematical model of radiofrequency ablation allows to understand, improve and optimise the outcome of the medical therapy. The main contribution of this work is the derivation of a tailored, yet expandable mathematical model, for the simulation, analysis, planning and control of radiofrequency ablation in complex situations. The dynamic model consists of partial differential equations that describe the potential and temperature distribution during intervention. To account for multipolar operation, time-dependent boundary conditions are introduced. Spatially distributed parameters, like tissue conductivity and blood perfusion, allow to describe the complex 3D environment representing diverse involved tissue types in the spine. To identify the key parameters affecting the prediction quality of the model, the influence of the parameters on the temperature distribution is investigated via a sensitivity analysis. Simulations underpin the quality of the derived model and the analysis approach. The proposed modelling and analysis schemes set the basis for intervention planning, state- and parameter estimation, and control. Copyright © 2016. Published by Elsevier Inc.

Electronic and magnetic properties of Fe-, Co-, and Ni-decorated BC3: A first-principles study

NASA Astrophysics Data System (ADS)

Zhu, Jingzhong; Zhao, Yinchang; Zulfiqar, Muhammad; Zeng, Shuming; Ni, Jun

2018-05-01

The electronic and magnetic properties of Fe-, Co-, and Ni-decorated two dimensional (2D) BC3 are systematically investigated by first-principles calculations. We find that the Fe, Co, and Ni atoms can be strongly adsorbed on the hollow sites of 2D BC3. Fe and Co adatoms are more stable when adsorbed on the hollow sites of the carbon rings in the 2D BC3, while the hollow sites of boron-carbon rings in the 2D BC3 are the most stable sites for the adsorption of Ni adatoms. These proposed metal-BC3 complexes exhibit interesting electronic and magnetic behaviors. In particular, the Fe-BC3 and Co-BC3 complexes are metals with magnetic ground states , while the Ni-BC3 complex behaves as a nonmagnetic semiconductor with a direct bandgap. Furthermore, our magnetic analysis reveals that induced magnetism in the Fe-BC3 and Co-BC3 complexes arises from their local magnetic moments. Functionalization of 2D BC3 through these metal-adatom adsorption appears to be a promising way to extend its applications.

Learning in 3-D Multiuser Virtual Environments: Exploring the Use of Unique 3-D Attributes for Online Problem-Based Learning

ERIC Educational Resources Information Center

Omale, Nicholas; Hung, Wei-Chen; Luetkehans, Lara; Cooke-Plagwitz, Jessamine

2009-01-01

The purpose of this article is to present the results of a study conducted to investigate how the attributes of 3-D technology such as avatars, 3-D space, and comic style bubble dialogue boxes affect participants' social, cognitive, and teaching presences in a blended problem-based learning environment. The community of inquiry model was adopted…

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sensoy, Ozge; Weinstein, Harel

Helix-8 (Hx8) is a structurally conserved amphipathic helical motif in class-A GPCRs, adjacent to the C-terminal sequence that is responsible for PDZ-domain-recognition. The Hx8 segment in the dopamine D2 receptor (D2R) constitutes the C-terminal segment and we investigate its role in the function of D2R by studying the interaction with the PDZ-containing GIPC1 using homology models based on the X-ray structures of very closely related analogs: the D3R for the D2R model, and the PDZ domain of GIPC2 for GIPC1–PDZ. The mechanism of this interaction was investigated with all-atom unbiased molecular dynamics (MD) simulations that reveal the role of themore » membrane in maintaining the helical fold of Hx8, and with biased MD simulations to elucidate the energy drive for the interaction with the GIPC1–PDZ. We found that it becomes more favorable energetically for Hx8 to adopt the extended conformation observed in all PDZ–ligand complexes when it moves away from the membrane, and that C-terminus palmitoylation of D2R enhanced membrane penetration by the Hx8 backbone. De-palmitoylation enables Hx8 to move out into the aqueous environment for interaction with the PDZ domain. All-atom unbiased MD simulations of the full D2R–GIPC1-PDZ complex in sphingolipid/cholesterol membranes show that the D2R carboxyl C-terminus samples the region of the conserved GFGL motif located on the carboxylate-binding loop of the GIPC1–PDZ, and the entire complex distances itself from the membrane interface. Altogether, these results outline a likely mechanism of Hx8 involvement in the interaction of the GPCR with PDZ-domains in the course of signaling.« less

Use of cues in virtual reality depends on visual feedback.

PubMed

Fulvio, Jacqueline M; Rokers, Bas

2017-11-22

3D motion perception is of central importance to daily life. However, when tested in laboratory settings, sensitivity to 3D motion signals is found to be poor, leading to the view that heuristics and prior assumptions are critical for 3D motion perception. Here we explore an alternative: sensitivity to 3D motion signals is context-dependent and must be learned based on explicit visual feedback in novel environments. The need for action-contingent visual feedback is well-established in the developmental literature. For example, young kittens that are passively moved through an environment, but unable to move through it themselves, fail to develop accurate depth perception. We find that these principles also obtain in adult human perception. Observers that do not experience visual consequences of their actions fail to develop accurate 3D motion perception in a virtual reality environment, even after prolonged exposure. By contrast, observers that experience the consequences of their actions improve performance based on available sensory cues to 3D motion. Specifically, we find that observers learn to exploit the small motion parallax cues provided by head jitter. Our findings advance understanding of human 3D motion processing and form a foundation for future study of perception in virtual and natural 3D environments.

Novel Materials for 3D Printing by Photopolymerization.

PubMed

Layani, Michael; Wang, Xiaofeng; Magdassi, Shlomo

2018-05-13

The field of 3D printing, also known as additive manufacturing (AM), is developing rapidly in both academic and industrial research environments. New materials and printing technologies, which enable rapid and multimaterial printing, have given rise to new applications and utilizations. However, the main bottleneck for achieving many more applications is the lack of materials with new physical properties. Here, some of the recent reports on novel materials in this field, such as ceramics, glass, shape-memory polymers, and electronics, are reviewed. Although new materials have been reported for all three main printing approaches-fused deposition modeling, binder jetting or laser sintering/melting, and photopolymerization-based approaches, apparently, most of the novel physicochemical properties are associated with materials printed by photopolymerization approaches. Furthermore, the high resolution that can be achieved using this type of 3D printing, together with the new properties, has resulted in new implementations such as microfluidic, biomedical devices, and soft robotics. Therefore, the focus here is on photopolymerization-based additive manufacturing including the recent development of new methods, novel monomers, and photoinitiators, which result in previously inaccessible applications such as complex ceramic structures, embedded electronics, and responsive 3D objects. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

RNA Bricks—a database of RNA 3D motifs and their interactions

PubMed Central

Chojnowski, Grzegorz; Waleń, Tomasz; Bujnicki, Janusz M.

2014-01-01

The RNA Bricks database (http://iimcb.genesilico.pl/rnabricks), stores information about recurrent RNA 3D motifs and their interactions, found in experimentally determined RNA structures and in RNA–protein complexes. In contrast to other similar tools (RNA 3D Motif Atlas, RNA Frabase, Rloom) RNA motifs, i.e. ‘RNA bricks’ are presented in the molecular environment, in which they were determined, including RNA, protein, metal ions, water molecules and ligands. All nucleotide residues in RNA bricks are annotated with structural quality scores that describe real-space correlation coefficients with the electron density data (if available), backbone geometry and possible steric conflicts, which can be used to identify poorly modeled residues. The database is also equipped with an algorithm for 3D motif search and comparison. The algorithm compares spatial positions of backbone atoms of the user-provided query structure and of stored RNA motifs, without relying on sequence or secondary structure information. This enables the identification of local structural similarities among evolutionarily related and unrelated RNA molecules. Besides, the search utility enables searching ‘RNA bricks’ according to sequence similarity, and makes it possible to identify motifs with modified ribonucleotide residues at specific positions. PMID:24220091

High performance 3D adaptive filtering for DSP based portable medical imaging systems

NASA Astrophysics Data System (ADS)

Bockenbach, Olivier; Ali, Murtaza; Wainwright, Ian; Nadeski, Mark

2015-03-01

Portable medical imaging devices have proven valuable for emergency medical services both in the field and hospital environments and are becoming more prevalent in clinical settings where the use of larger imaging machines is impractical. Despite their constraints on power, size and cost, portable imaging devices must still deliver high quality images. 3D adaptive filtering is one of the most advanced techniques aimed at noise reduction and feature enhancement, but is computationally very demanding and hence often cannot be run with sufficient performance on a portable platform. In recent years, advanced multicore digital signal processors (DSP) have been developed that attain high processing performance while maintaining low levels of power dissipation. These processors enable the implementation of complex algorithms on a portable platform. In this study, the performance of a 3D adaptive filtering algorithm on a DSP is investigated. The performance is assessed by filtering a volume of size 512x256x128 voxels sampled at a pace of 10 MVoxels/sec with an Ultrasound 3D probe. Relative performance and power is addressed between a reference PC (Quad Core CPU) and a TMS320C6678 DSP from Texas Instruments.

Web-based hydrodynamics computing

NASA Astrophysics Data System (ADS)

Shimoide, Alan; Lin, Luping; Hong, Tracie-Lynne; Yoon, Ilmi; Aragon, Sergio R.

2005-01-01

Proteins are long chains of amino acids that have a definite 3-d conformation and the shape of each protein is vital to its function. Since proteins are normally in solution, hydrodynamics (describes the movement of solvent around a protein as a function of shape and size of the molecule) can be used to probe the size and shape of proteins compared to those derived from X-ray crystallography. The computation chain needed for these hydrodynamics calculations consists of several separate programs by different authors on various platforms and often requires 3D visualizations of intermediate results. Due to the complexity, tools developed by a particular research group are not readily available for use by other groups, nor even by the non-experts within the same research group. To alleviate this situation, and to foment the easy and wide distribution of computational tools worldwide, we developed a web based interactive computational environment (WICE) including interactive 3D visualization that can be used with any web browser. Java based technologies were used to provide a platform neutral, user-friendly solution. Java Server Pages (JSP), Java Servlets, Java Beans, JOGL (Java bindings for OpenGL), and Java Web Start were used to create a solution that simplifies the computing chain for the user allowing the user to focus on their scientific research. WICE hides complexity from the user and provides robust and sophisticated visualization through a web browser.

Web-based hydrodynamics computing

NASA Astrophysics Data System (ADS)

Shimoide, Alan; Lin, Luping; Hong, Tracie-Lynne; Yoon, Ilmi; Aragon, Sergio R.

2004-12-01

Proteins are long chains of amino acids that have a definite 3-d conformation and the shape of each protein is vital to its function. Since proteins are normally in solution, hydrodynamics (describes the movement of solvent around a protein as a function of shape and size of the molecule) can be used to probe the size and shape of proteins compared to those derived from X-ray crystallography. The computation chain needed for these hydrodynamics calculations consists of several separate programs by different authors on various platforms and often requires 3D visualizations of intermediate results. Due to the complexity, tools developed by a particular research group are not readily available for use by other groups, nor even by the non-experts within the same research group. To alleviate this situation, and to foment the easy and wide distribution of computational tools worldwide, we developed a web based interactive computational environment (WICE) including interactive 3D visualization that can be used with any web browser. Java based technologies were used to provide a platform neutral, user-friendly solution. Java Server Pages (JSP), Java Servlets, Java Beans, JOGL (Java bindings for OpenGL), and Java Web Start were used to create a solution that simplifies the computing chain for the user allowing the user to focus on their scientific research. WICE hides complexity from the user and provides robust and sophisticated visualization through a web browser.

Polysaccharide-based hydrogels with tunable composition as 3D cell culture systems.

PubMed

Gentilini, Roberta; Munarin, Fabiola; Bloise, Nora; Secchi, Eleonora; Visai, Livia; Tanzi, Maria Cristina; Petrini, Paola

2018-04-01

To date, cell cultures have been created either on 2-dimensional (2D) polystyrene surfaces or in 3-dimensional (3D) systems, which do not offer a controlled chemical composition, and which lack the soft environment encountered in vivo and the chemical stimuli that promote cell proliferation and allow complex cellular behavior. In this study, pectin-based hydrogels were developed and are proposed as versatile cell culture systems. Pectin-based hydrogels were produced by internally crosslinking pectin with calcium carbonate at different initial pH, aiming to control crosslinking kinetics and degree. Additionally, glucose and glutamine were added as additives, and their effects on the viscoelastic properties of the hydrogels and on cell viability were investigated. Pectin hydrogels showed in high cell viability and shear-thinning behavior. Independently of hydrogel composition, an initial swelling was observed, followed by a low percentage of weight variation and a steady-state stage. The addition of glucose and glutamine to pectin-based hydrogels rendered higher cell viability up to 90%-98% after 1 hour of incubation, and these hydrogels were maintained for up to 7 days of culture, yet no effect on viscoelastic properties was detected. Pectin-based hydrogels that offer tunable composition were developed successfully. They are envisioned as synthetic extracellular matrix (ECM) either to study complex cellular behaviors or to be applied as tissue engineering substitutes.

Crystal structures of D-psicose 3-epimerase from Clostridium cellulolyticum H10 and its complex with ketohexose sugars.

PubMed

Chan, Hsiu-Chien; Zhu, Yueming; Hu, Yumei; Ko, Tzu-Ping; Huang, Chun-Hsiang; Ren, Feifei; Chen, Chun-Chi; Ma, Yanhe; Guo, Rey-Ting; Sun, Yuanxia

2012-02-01

D-psicose 3-epimerase (DPEase) is demonstrated to be useful in the bioproduction of D-psicose, a rare hexose sugar, from D-fructose, found plenty in nature. Clostridium cellulolyticum H10 has recently been identified as a DPEase that can epimerize D-fructose to yield D-psicose with a much higher conversion rate when compared with the conventionally used DTEase. In this study, the crystal structure of the C. cellulolyticum DPEase was determined. The enzyme assembles into a tetramer and each subunit shows a (β/α)(8) TIM barrel fold with a Mn(2+) metal ion in the active site. Additional crystal structures of the enzyme in complex with substrates/products (D-psicose, D-fructose, D-tagatose and D-sorbose) were also determined. From the complex structures of C. cellulolyticum DPEase with D-psicose and D-fructose, the enzyme has much more interactions with D-psicose than D-fructose by forming more hydrogen bonds between the substrate and the active site residues. Accordingly, based on these ketohexose-bound complex structures, a C3-O3 proton-exchange mechanism for the conversion between D-psicose and D-fructose is proposed here. These results provide a clear idea for the deprotonation/protonation roles of E150 and E244 in catalysis.

Research on complex 3D tree modeling based on L-system

NASA Astrophysics Data System (ADS)

Gang, Chen; Bin, Chen; Yuming, Liu; Hui, Li

2018-03-01

L-system as a fractal iterative system could simulate complex geometric patterns. Based on the field observation data of trees and knowledge of forestry experts, this paper extracted modeling constraint rules and obtained an L-system rules set. Using the self-developed L-system modeling software the L-system rule set was parsed to generate complex tree 3d models.The results showed that the geometrical modeling method based on l-system could be used to describe the morphological structure of complex trees and generate 3D tree models.

Analysis of 3D Scan Measurement Distribution with Application to a Multi-Beam Lidar on a Rotating Platform.

PubMed

Morales, Jesús; Plaza-Leiva, Victoria; Mandow, Anthony; Gomez-Ruiz, Jose Antonio; Serón, Javier; García-Cerezo, Alfonso

2018-01-30

Multi-beam lidar (MBL) rangefinders are becoming increasingly compact, light, and accessible 3D sensors, but they offer limited vertical resolution and field of view. The addition of a degree-of-freedom to build a rotating multi-beam lidar (RMBL) has the potential to become a common solution for affordable rapid full-3D high resolution scans. However, the overlapping of multiple-beams caused by rotation yields scanning patterns that are more complex than in rotating single beam lidar (RSBL). In this paper, we propose a simulation-based methodology to analyze 3D scanning patterns which is applied to investigate the scan measurement distribution produced by the RMBL configuration. With this purpose, novel contributions include: (i) the adaption of a recent spherical reformulation of Ripley's K function to assess 3D sensor data distribution on a hollow sphere simulation; (ii) a comparison, both qualitative and quantitative, between scan patterns produced by an ideal RMBL based on a Velodyne VLP-16 (Puck) and those of other 3D scan alternatives (i.e., rotating 2D lidar and MBL); and (iii) a new RMBL implementation consisting of a portable tilting platform for VLP-16 scanners, which is presented as a case study for measurement distribution analysis as well as for the discussion of actual scans from representative environments. Results indicate that despite the particular sampling patterns given by a RMBL, its homogeneity even improves that of an equivalent RSBL.

Analysis of 3D Scan Measurement Distribution with Application to a Multi-Beam Lidar on a Rotating Platform

PubMed Central

Plaza-Leiva, Victoria; Serón, Javier

2018-01-01

Multi-beam lidar (MBL) rangefinders are becoming increasingly compact, light, and accessible 3D sensors, but they offer limited vertical resolution and field of view. The addition of a degree-of-freedom to build a rotating multi-beam lidar (RMBL) has the potential to become a common solution for affordable rapid full-3D high resolution scans. However, the overlapping of multiple-beams caused by rotation yields scanning patterns that are more complex than in rotating single beam lidar (RSBL). In this paper, we propose a simulation-based methodology to analyze 3D scanning patterns which is applied to investigate the scan measurement distribution produced by the RMBL configuration. With this purpose, novel contributions include: (i) the adaption of a recent spherical reformulation of Ripley’s K function to assess 3D sensor data distribution on a hollow sphere simulation; (ii) a comparison, both qualitative and quantitative, between scan patterns produced by an ideal RMBL based on a Velodyne VLP-16 (Puck) and those of other 3D scan alternatives (i.e., rotating 2D lidar and MBL); and (iii) a new RMBL implementation consisting of a portable tilting platform for VLP-16 scanners, which is presented as a case study for measurement distribution analysis as well as for the discussion of actual scans from representative environments. Results indicate that despite the particular sampling patterns given by a RMBL, its homogeneity even improves that of an equivalent RSBL. PMID:29385705

Student performance and appreciation using 3D vs. 2D vision in a virtual learning environment.

PubMed

de Boer, I R; Wesselink, P R; Vervoorn, J M

2016-08-01

The aim of this study was to investigate the differences in the performance and appreciation of students working in a virtual learning environment with two (2D)- or three (3D)-dimensional vision. One hundred and twenty-four randomly divided first-year dental students performed a manual dexterity exercise on the Simodont dental trainer with an automatic assessment. Group 1 practised in 2D vision and Group 2 in 3D. All of the students practised five times for 45 min and then took a test using the vision they had practised in. After test 1, all of the students switched the type of vision to control for the learning curve: Group 1 practised in 3D and took a test in 3D, whilst Group 2 practised in 2D and took the test in 2D. To pass, three of five exercises had to be successfully completed within a time limit. The students filled out a questionnaire after completing test 2. The results show that students working with 3D vision achieved significantly better results than students who worked in 2D. Ninety-five per cent of the students filled out the questionnaire, and over 90 per cent preferred 3D vision. The use of 3D vision in a virtual learning environment has a significant positive effect on the performance of the students as well as on their appreciation of the environment. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Development of a Novel Motor Imagery Control Technique and Application in a Gaming Environment

PubMed Central

Xue, Tao

2017-01-01

We present a methodology for a hybrid brain-computer interface (BCI) system, with the recognition of motor imagery (MI) based on EEG and blink EOG signals. We tested the BCI system in a 3D Tetris and an analogous 2D game playing environment. To enhance player's BCI control ability, the study focused on feature extraction from EEG and control strategy supporting Game-BCI system operation. We compared the numerical differences between spatial features extracted with common spatial pattern (CSP) and the proposed multifeature extraction. To demonstrate the effectiveness of 3D game environment at enhancing player's event-related desynchronization (ERD) and event-related synchronization (ERS) production ability, we set the 2D Screen Game as the comparison experiment. According to a series of statistical results, the group performing MI in the 3D Tetris environment showed more significant improvements in generating MI-associated ERD/ERS. Analysis results of game-score indicated that the players' scores presented an obvious uptrend in 3D Tetris environment but did not show an obvious downward trend in 2D Screen Game. It suggested that the immersive and rich-control environment for MI would improve the associated mental imagery and enhance MI-based BCI skills. PMID:28572817

Eu(III)-Fulvic Acid Complexation: Evidence of Fulvic Acid Concentration Dependent Interactions by Time-Resolved Luminescence Spectroscopy.

PubMed

Kouhail, Yasmine Z; Benedetti, Marc F; Reiller, Pascal E

2016-04-05

Europium speciation is investigated by time-resolved luminescence spectroscopy (TRLS) in the presence of Suwannee River fulvic acid (SRFA). From complexation isotherms built at different total Eu(III) concentrations, pH values, ionic strength, and SRFA concentrations, it appears that two luminescence behaviors of Eu(III) are occurring. The first part, at the lowest CSRFA values, is showing the typical luminescence evolution of Eu(III) complexed by humic substances--that is, the increase of the asymmetry ratio between the (5)D0 → (7)F2 and (5)D0 → (7)F1 transitions up to a plateau--, and the occurrence of a biexponential decay--the first decay being faster than free Eu(3+). At higher CSRFA, a second luminescence mode is detected as the asymmetry ratio is increasing again after the previous plateau, and could correspond to the formation of another type of complex, and/or it can reflect a different spatial organization of complexed europium within the SRFA structure. The luminescence decay keeps on evolving but link to hydration number is not straightforward due to quenching mechanisms. The Eu(III) chemical environment evolution with CSRFA is also ionic strength dependent. These observations suggest that in addition to short-range interactions--intraparticulate complexation--, there might be interactions at longer range--interparticulate repulsion--between particles that are complexing Eu(III) at high CSRFA. These interactions are not yet accounted by the different complexation models.

Controlled Breast Cancer Microarrays for the Deconvolution of Cellular Multilayering and Density Effects upon Drug Responses

PubMed Central

Håkanson, Maria; Kobel, Stefan; Lutolf, Matthias P.; Textor, Marcus; Cukierman, Edna; Charnley, Mirren

2012-01-01

Background Increasing evidence shows that the cancer microenvironment affects both tumorigenesis and the response of cancer to drug treatment. Therefore in vitro models that selectively reflect characteristics of the in vivo environment are greatly needed. Current methods allow us to screen the effect of extrinsic parameters such as matrix composition and to model the complex and three-dimensional (3D) cancer environment. However, 3D models that reflect characteristics of the in vivo environment are typically too complex and do not allow the separation of discrete extrinsic parameters. Methodology/Principal Findings In this study we used a poly(ethylene glycol) (PEG) hydrogel-based microwell array to model breast cancer cell behavior in multilayer cell clusters that allows a rigorous control of the environment. The innovative array fabrication enables different matrix proteins to be integrated into the bottom surface of microwells. Thereby, extrinsic parameters including dimensionality, type of matrix coating and the extent of cell-cell adhesion could be independently studied. Our results suggest that cell to matrix interactions and increased cell-cell adhesion, at high cell density, induce independent effects on the response to Taxol in multilayer breast cancer cell clusters. In addition, comparing the levels of apoptosis and proliferation revealed that drug resistance mediated by cell-cell adhesion can be related to altered cell cycle regulation. Conversely, the matrix-dependent response to Taxol did not correlate with proliferation changes suggesting that cell death inhibition may be responsible for this effect. Conclusions/Significance The application of the PEG hydrogel platform provided novel insight into the independent role of extrinsic parameters controlling drug response. The presented platform may not only become a useful tool for basic research related to the role of the cancer microenvironment but could also serve as a complementary platform for in vitro drug development. PMID:22792141

4D-SFM Photogrammetry for Monitoring Sediment Dynamics in a Debris-Flow Catchment: Software Testing and Results Comparison

NASA Astrophysics Data System (ADS)

Cucchiaro, S.; Maset, E.; Fusiello, A.; Cazorzi, F.

2018-05-01

In recent years, the combination of Structure-from-Motion (SfM) algorithms and UAV-based aerial images has revolutionised 3D topographic surveys for natural environment monitoring, offering low-cost, fast and high quality data acquisition and processing. A continuous monitoring of the morphological changes through multi-temporal (4D) SfM surveys allows, e.g., to analyse the torrent dynamic also in complex topography environment like debris-flow catchments, provided that appropriate tools and procedures are employed in the data processing steps. In this work we test two different software packages (3DF Zephyr Aerial and Agisoft Photoscan) on a dataset composed of both UAV and terrestrial images acquired on a debris-flow reach (Moscardo torrent - North-eastern Italian Alps). Unlike other papers in the literature, we evaluate the results not only on the raw point clouds generated by the Structure-from- Motion and Multi-View Stereo algorithms, but also on the Digital Terrain Models (DTMs) created after post-processing. Outcomes show differences between the DTMs that can be considered irrelevant for the geomorphological phenomena under analysis. This study confirms that SfM photogrammetry can be a valuable tool for monitoring sediment dynamics, but accurate point cloud post-processing is required to reliably localize geomorphological changes.

Sensitivity Analysis of Multidisciplinary Rotorcraft Simulations

NASA Technical Reports Server (NTRS)

Wang, Li; Diskin, Boris; Biedron, Robert T.; Nielsen, Eric J.; Bauchau, Olivier A.

2017-01-01

A multidisciplinary sensitivity analysis of rotorcraft simulations involving tightly coupled high-fidelity computational fluid dynamics and comprehensive analysis solvers is presented and evaluated. An unstructured sensitivity-enabled Navier-Stokes solver, FUN3D, and a nonlinear flexible multibody dynamics solver, DYMORE, are coupled to predict the aerodynamic loads and structural responses of helicopter rotor blades. A discretely-consistent adjoint-based sensitivity analysis available in FUN3D provides sensitivities arising from unsteady turbulent flows and unstructured dynamic overset meshes, while a complex-variable approach is used to compute DYMORE structural sensitivities with respect to aerodynamic loads. The multidisciplinary sensitivity analysis is conducted through integrating the sensitivity components from each discipline of the coupled system. Numerical results verify accuracy of the FUN3D/DYMORE system by conducting simulations for a benchmark rotorcraft test model and comparing solutions with established analyses and experimental data. Complex-variable implementation of sensitivity analysis of DYMORE and the coupled FUN3D/DYMORE system is verified by comparing with real-valued analysis and sensitivities. Correctness of adjoint formulations for FUN3D/DYMORE interfaces is verified by comparing adjoint-based and complex-variable sensitivities. Finally, sensitivities of the lift and drag functions obtained by complex-variable FUN3D/DYMORE simulations are compared with sensitivities computed by the multidisciplinary sensitivity analysis, which couples adjoint-based flow and grid sensitivities of FUN3D and FUN3D/DYMORE interfaces with complex-variable sensitivities of DYMORE structural responses.

A model of the complex between human {beta}-microseminoprotein and CRISP-3 based on NMR data

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ghasriani, Houman; Fernlund, Per; Udby, Lene

2009-01-09

{beta}-Microseminoprotein (MSP), a 10 kDa seminal plasma protein, forms a tight complex with cysteine-rich secretory protein 3 (CRISP-3) from granulocytes. The 3D structure of human MSP has been determined but there is as yet no 3D structure for CRISP-3. We have now studied the complex between human MSP and CRISP-3 with multidimensional NMR. {sup 15}N-HSQC spectra show substantial differences between free and complexed hMSP. Using several 3D-NMR spectra of triply labeled hMSP in complex with a recombinant N-terminal domain of CRISP-3, most of the backbone of hMSP could be assigned. The data show that only one side of hMSP, comprisingmore » {beta}-strands 1, 4, 5, and 8 are affected by the complex formation, indicating that {beta}-strands 1 and 8 form the main binding surface. Based on this we present a tentative structure for the hMSP-CRISP-3 complex using the known crystal structure of triflin as a model of CRISP-3.« less

DWARF 53 acts as a repressor of strigolactone signalling in rice

NASA Astrophysics Data System (ADS)

Jiang, Liang; Liu, Xue; Xiong, Guosheng; Liu, Huihui; Chen, Fulu; Wang, Lei; Meng, Xiangbing; Liu, Guifu; Yu, Hong; Yuan, Yundong; Yi, Wei; Zhao, Lihua; Ma, Honglei; He, Yuanzheng; Wu, Zhongshan; Melcher, Karsten; Qian, Qian; Xu, H. Eric; Wang, Yonghong; Li, Jiayang

2013-12-01

Strigolactones (SLs) are a group of newly identified plant hormones that control plant shoot branching. SL signalling requires the hormone-dependent interaction of DWARF 14 (D14), a probable candidate SL receptor, with DWARF 3 (D3), an F-box component of the Skp-Cullin-F-box (SCF) E3 ubiquitin ligase complex. Here we report the characterization of a dominant SL-insensitive rice (Oryza sativa) mutant dwarf 53 (d53) and the cloning of D53, which encodes a substrate of the SCFD3 ubiquitination complex and functions as a repressor of SL signalling. Treatments with GR24, a synthetic SL analogue, cause D53 degradation via the proteasome in a manner that requires D14 and the SCFD3 ubiquitin ligase, whereas the dominant form of D53 is resistant to SL-mediated degradation. Moreover, D53 can interact with transcriptional co-repressors known as TOPLESS-RELATED PROTEINS. Our results suggest a model of SL signalling that involves SL-dependent degradation of the D53 repressor mediated by the D14-D3 complex.

The Hologram in My Hand: How Effective is Interactive Exploration of 3D Visualizations in Immersive Tangible Augmented Reality?

PubMed

Bach, Benjamin; Sicat, Ronell; Beyer, Johanna; Cordeil, Maxime; Pfister, Hanspeter

2018-01-01

We report on a controlled user study comparing three visualization environments for common 3D exploration. Our environments differ in how they exploit natural human perception and interaction capabilities. We compare an augmented-reality head-mounted display (Microsoft HoloLens), a handheld tablet, and a desktop setup. The novel head-mounted HoloLens display projects stereoscopic images of virtual content into a user's real world and allows for interaction in-situ at the spatial position of the 3D hologram. The tablet is able to interact with 3D content through touch, spatial positioning, and tangible markers, however, 3D content is still presented on a 2D surface. Our hypothesis is that visualization environments that match human perceptual and interaction capabilities better to the task at hand improve understanding of 3D visualizations. To better understand the space of display and interaction modalities in visualization environments, we first propose a classification based on three dimensions: perception, interaction, and the spatial and cognitive proximity of the two. Each technique in our study is located at a different position along these three dimensions. We asked 15 participants to perform four tasks, each task having different levels of difficulty for both spatial perception and degrees of freedom for interaction. Our results show that each of the tested environments is more effective for certain tasks, but that generally the desktop environment is still fastest and most precise in almost all cases.

The Research and Evaluation of Road Environment in the Block of City Based on 3-D Streetscape Data

NASA Astrophysics Data System (ADS)

Guan, L.; Ding, Y.; Ge, J.; Yang, H.; Feng, X.; Chen, P.

2018-04-01

This paper focus on the problem of the street environment of block unit, based on making clear the acquisition mode and characteristics of 3D streetscape data, the paper designs the assessment model of regional block unit based on 3D streetscape data. The 3D streetscape data with the aid of oblique photogrammetry surveying and mobile equipment, will greatly improve the efficiency and accuracy of urban regional assessment, and expand the assessment scope. Based on the latest urban regional assessment model, with the street environment assessment model of the current situation, this paper analyzes the street form and street environment assessment of current situation in the typical area of Beijing. Through the street environment assessment of block unit, we found that in the megacity street environment assessment model of block unit based on 3D streetscape data has greatly help to improve the assessment efficiency and accuracy. At the same time, motor vehicle lane, green shade deficiency, bad railings and street lost situation is still very serious in Beijing, the street environment improvement of the block unit is still a heavy task. The research results will provide data support for urban fine management and urban design, and provide a solid foundation for the improvement of city image.

A comparison of the accuracy of intraoral scanners using an intraoral environment simulator

PubMed Central

Park, Hye-Nan; Lim, Young-Jun; Yi, Won-Jin

2018-01-01

PURPOSE The aim of this study was to design an intraoral environment simulator and to assess the accuracy of two intraoral scanners using the simulator. MATERIALS AND METHODS A box-shaped intraoral environment simulator was designed to simulate two specific intraoral environments. The cast was scanned 10 times by Identica Blue (MEDIT, Seoul, South Korea), TRIOS (3Shape, Copenhagen, Denmark), and CS3500 (Carestream Dental, Georgia, USA) scanners in the two simulated groups. The distances between the left and right canines (D3), first molars (D6), second molars (D7), and the left canine and left second molar (D37) were measured. The distance data were analyzed by the Kruskal-Wallis test. RESULTS The differences in intraoral environments were not statistically significant (P>.05). Between intraoral scanners, statistically significant differences (P<.05) were revealed by the Kruskal-Wallis test with regard to D3 and D6. CONCLUSION No difference due to the intraoral environment was revealed. The simulator will contribute to the higher accuracy of intraoral scanners in the future. PMID:29503715

Hydration of nucleic acid fragments: comparison of theory and experiment for high-resolution crystal structures of RNA, DNA, and DNA-drug complexes.

PubMed Central

Hummer, G; García, A E; Soumpasis, D M

1995-01-01

A computationally efficient method to describe the organization of water around solvated biomolecules is presented. It is based on a statistical mechanical expression for the water-density distribution in terms of particle correlation functions. The method is applied to analyze the hydration of small nucleic acid molecules in the crystal environment, for which high-resolution x-ray crystal structures have been reported. Results for RNA [r(ApU).r(ApU)] and DNA [d(CpG).d(CpG) in Z form and with parallel strand orientation] and for DNA-drug complexes [d(CpG).d(CpG) with the drug proflavine intercalated] are described. A detailed comparison of theoretical and experimental data shows positional agreement for the experimentally observed water sites. The presented method can be used for refinement of the water structure in x-ray crystallography, hydration analysis of nuclear magnetic resonance structures, and theoretical modeling of biological macromolecules such as molecular docking studies. The speed of the computations allows hydration analyses of molecules of almost arbitrary size (tRNA, protein-nucleic acid complexes, etc.) in the crystal environment and in aqueous solution. Images FIGURE 1 FIGURE 2 FIGURE 5 FIGURE 6 FIGURE 9 FIGURE 12 FIGURE 13 PMID:7542034

Utilisation of three-dimensional printed heart models for operative planning of complex congenital heart defects.

PubMed

Olejník, Peter; Nosal, Matej; Havran, Tomas; Furdova, Adriana; Cizmar, Maros; Slabej, Michal; Thurzo, Andrej; Vitovic, Pavol; Klvac, Martin; Acel, Tibor; Masura, Jozef

2017-01-01

To evaluate the accuracy of the three-dimensional (3D) printing of cardiovascular structures. To explore whether utilisation of 3D printed heart replicas can improve surgical and catheter interventional planning in patients with complex congenital heart defects. Between December 2014 and November 2015 we fabricated eight cardiovascular models based on computed tomography data in patients with complex spatial anatomical relationships of cardiovascular structures. A Bland-Altman analysis was used to assess the accuracy of 3D printing by comparing dimension measurements at analogous anatomical locations between the printed models and digital imagery data, as well as between printed models and in vivo surgical findings. The contribution of 3D printed heart models for perioperative planning improvement was evaluated in the four most representative patients. Bland-Altman analysis confirmed the high accuracy of 3D cardiovascular printing. Each printed model offered an improved spatial anatomical orientation of cardiovascular structures. Current 3D printers can produce authentic copies of patients` cardiovascular systems from computed tomography data. The use of 3D printed models can facilitate surgical or catheter interventional procedures in patients with complex congenital heart defects due to better preoperative planning and intraoperative orientation.

a 3d Information System for the Documentation of Archaeologica L Excavations

NASA Astrophysics Data System (ADS)

Ardissone, P.; Bornaz, L.; Degattis, G.; Domaine, R.

2013-07-01

Documentation of archaeological and cultural heritage sites is at the heart of the archaeological process and an important component in cultural heritage research, presentation and restorations. In 2012 the Superintendence of Cultural Heritage of Aosta Valley - IT (Soprintendenza per i Beni e le Attività Culturali della Region e Autonoma Valle d'Aosta) carried out a complex archaeological excavation in a composite archaeological context, situated an urban background: the Aosta city centre. This archaeological excavation has been characterized by the classical urban archaeological issues: little space, short time, complex stratigraphy. Moreover the investigations have come out several structures and walls that required safety and conservation measures. Ad hoc 3D solutions carried out a complete 3D survey of the area in 10 different time/situations of the Archaeological digs, chosen in collaborations with the archaeological staff. In this way a multi temporal 3D description of the site has been provided for the archaeological analysis and for the project of the restorations activities. The 3D surveys has been carried out integrating GPS, laser scanner technology and photogrammetry. In order to meet the needs of the site, and its complex logistics and to obtain products that guarantee the high quality and detail required for archaeological analysis, we have developed different procedures and methodologies: hdr imaging for 3D model with correct, consistent and uniform colours, noise filtering and people filtering, for the removal of interference between laser instrument and object of the survey, Advanced laser scanner triangulation, in order to consider both artificial and natural tie points, for a correct registration of a huge amount of scans. Single image orientation on 3D data, in order to integrate the laser data with data coming from digital photogrammetry (faster on the field than the laser scanner survey, than used in certain situations). The results of all these methodologies and procedures will be presented and described in the article. For the documentation of the archaeological excavations and for the management of the conservation activities (condition assessment, planning, and conservation work). Ad Hoc 3D solutions has costumized 2 special plug-ins of its own software platform Ad Hoc: Ad Hoc Archaeology and Ad Hoc Conservation. The software platform integrates a 3D database management system. All information (measurements, plotting, areas of interests…) are organized according to their correct 3D position. They can be queried using attributes, geometric characteristics or their spatial position. The Ad Hoc Archaeology plug-in allows archeologists to fill out UUSS sheets in an internal database, put them in the correct location within the 3D model of the site, define the mutual relations between the UUSS, divide the different archaeological phases. A simple interface will facilitate the construction of the stratigraphic chart (matrix), in a 3D environment as well (matrix 3D). The Ad Hoc Conservation plug-in permits conservators and restorers to create relationships between the different approaches and descriptions of the same parts of the monument, i.e.: between stratigraphyc units or historical phases and architectural components and/or decay pathologies. The 3D DBMS conservation module uses a codified terminology based on "ICOMOS illustrated glossary of stone deterioration" and other glossary. Specific tools permits restorers to compute correctly surfaces and volumes. In this way decay extension and intensity can be measured with high precision and with an high level of detail, for a correct time and costs estimation of each conservation step.

KENNEDY SPACE CENTER, FLA. - In the gantry on Launch Complex 17-B, Cape Canaveral Air Force Station, workers start removing the canister from around the Mars Exploration Rover 1 (MER-B). The second of twin rovers being sent to Mars, it is equipped with a robotic arm, a drilling tool, three spectrometers, and four pairs of cameras that allow it to have a human-like, 3D view of the terrain. Each rover could travel as far as 100 meters in one day to act as Mars scientists' eyes and hands, exploring an environment where humans can't yet go. MER-B is scheduled to launch June 26 at one of two available times, 12:27:31 a.m. EDT or 1:08:45 a.m. EDT.

NASA Image and Video Library

2003-06-17

KENNEDY SPACE CENTER, FLA. - In the gantry on Launch Complex 17-B, Cape Canaveral Air Force Station, workers start removing the canister from around the Mars Exploration Rover 1 (MER-B). The second of twin rovers being sent to Mars, it is equipped with a robotic arm, a drilling tool, three spectrometers, and four pairs of cameras that allow it to have a human-like, 3D view of the terrain. Each rover could travel as far as 100 meters in one day to act as Mars scientists' eyes and hands, exploring an environment where humans can't yet go. MER-B is scheduled to launch June 26 at one of two available times, 12:27:31 a.m. EDT or 1:08:45 a.m. EDT.

COMPLEX CONDITIONAL CONTROL BY PIGEONS IN A CONTINUOUS VIRTUAL ENVIRONMENT

PubMed Central

Qadri, Muhammad A. J.; Reid, Sean; Cook, Robert G.

2016-01-01

We tested two pigeons in a continuously streaming digital environment. Using animation software that constantly presented a dynamic, three-dimensional (3D) environment, the animals were tested with a conditional object identification task. The correct object at a given time depended on the virtual context currently streaming in front of the pigeon. Pigeons were required to accurately peck correct target objects in the environment for food reward, while suppressing any pecks to intermixed distractor objects which delayed the next object’s presentation. Experiment 1 established that the pigeons’ discrimination of two objects could be controlled by the surface material of the digital terrain. Experiment 2 established that the pigeons’ discrimination of four objects could be conjunctively controlled by both the surface material and topography of the streaming environment. These experiments indicate that pigeons can simultaneously process and use at least two context cues from a streaming environment to control their identification behavior of passing objects. These results add to the promise of testing interactive digital environments with animals to advance our understanding of cognition and behavior. PMID:26781058

Planar Gradient Diffusion System to Investigate Chemotaxis in a 3D Collagen Matrix.

PubMed

Stout, David A; Toyjanova, Jennet; Franck, Christian

2015-06-12

The importance of cell migration can be seen through the development of human life. When cells migrate, they generate forces and transfer these forces to their surrounding area, leading to cell movement and migration. In order to understand the mechanisms that can alter and/or affect cell migration, one can study these forces. In theory, understanding the fundamental mechanisms and forces underlying cell migration holds the promise of effective approaches for treating diseases and promoting cellular transplantation. Unfortunately, modern chemotaxis chambers that have been developed are usually restricted to two dimensions (2D) and have complex diffusion gradients that make the experiment difficult to interpret. To this end, we have developed, and describe in this paper, a direct-viewing chamber for chemotaxis studies, which allows one to overcome modern chemotaxis chamber obstacles able to measure cell forces and specific concentration within the chamber in a 3D environment to study cell 3D migration. More compelling, this approach allows one to successfully model diffusion through 3D collagen matrices and calculate the coefficient of diffusion of a chemoattractant through multiple different concentrations of collagen, while keeping the system simple and user friendly for traction force microscopy (TFM) and digital volume correlation (DVC) analysis.

Implementation and clinical application of a deformation method for fast simulation of biological tissue formed by fibers and fluid.

PubMed

Sardinha, Ana Gabriella de Oliveira; Oyama, Ceres Nunes de Resende; de Mendonça Maroja, Armando; Costa, Ivan F

2016-01-01

The aim of this paper is to provide a general discussion, algorithm, and actual working programs of the deformation method for fast simulation of biological tissue formed by fibers and fluid. In order to demonstrate the benefit of the clinical applications software, we successfully used our computational program to deform a 3D breast image acquired from patients, using a 3D scanner, in a real hospital environment. The method implements a quasi-static solution for elastic global deformations of objects. Each pair of vertices of the surface is connected and defines an elastic fiber. The set of all the elastic fibers defines a mesh of smaller size than the volumetric meshes, allowing for simulation of complex objects with less computational effort. The behavior similar to the stress tensor is obtained by the volume conservation equation that mixes the 3D coordinates. Step by step, we show the computational implementation of this approach. As an example, a 2D rectangle formed by only 4 vertices is solved and, for this simple geometry, all intermediate results are shown. On the other hand, actual implementations of these ideas in the form of working computer routines are provided for general 3D objects, including a clinical application.

Three-Dimensional in Vitro Cell Culture Models in Drug Discovery and Drug Repositioning

PubMed Central

Langhans, Sigrid A.

2018-01-01

Drug development is a lengthy and costly process that proceeds through several stages from target identification to lead discovery and optimization, preclinical validation and clinical trials culminating in approval for clinical use. An important step in this process is high-throughput screening (HTS) of small compound libraries for lead identification. Currently, the majority of cell-based HTS is being carried out on cultured cells propagated in two-dimensions (2D) on plastic surfaces optimized for tissue culture. At the same time, compelling evidence suggests that cells cultured in these non-physiological conditions are not representative of cells residing in the complex microenvironment of a tissue. This discrepancy is thought to be a significant contributor to the high failure rate in drug discovery, where only a low percentage of drugs investigated ever make it through the gamut of testing and approval to the market. Thus, three-dimensional (3D) cell culture technologies that more closely resemble in vivo cell environments are now being pursued with intensity as they are expected to accommodate better precision in drug discovery. Here we will review common approaches to 3D culture, discuss the significance of 3D cultures in drug resistance and drug repositioning and address some of the challenges of applying 3D cell cultures to high-throughput drug discovery. PMID:29410625

Enzymatic hydrolysis of p-nitroacetanilide: mechanistic studies of the aryl acylamidase from Pseudomonas fluorescens.

PubMed

Stein, Ross L

2002-01-22

Aryl acylamidase (EC 3.1.5.13; AAA) catalyzes the hydrolysis of p-nitroacetanilide (PNAA) via the standard three-step mechanism of serine hydrolases: binding of substrate (K(s)), acylation of active-site serine (k(acyl)), and hydrolytic deacylation (k(deacyl)). Key mechanistic findings that emerged from this study include that (1) AAA requires a deprotonated base with a pK(a) of 8.3 for expression of full activity toward PNAA. Limiting values of kinetic parameters at high pH are k(c) = 7 s(-1), K(m) = 20 microM, and k(c)/K(m) = 340 000 M(-1) s(-1). (2) At pH 10, where all the isotope effects were conducted, k(c) is equally rate-limited by k(acyl) and k(deacyl). (3) The following isotope effects were determined: (D)()2(O)(k(c)/K(m)) = 1.7 +/- 0.2, (D)()2(O)k(c) = 3.5 +/- 0.3, and (beta)(D)(k(c)/K(m)) = 0.83 +/- 0.04, (beta)(D)k(c) = 0.96 +/- 0.01. These values, together with proton inventories for k(c)/K(m) and k(c), suggest the following mechanism: (i) The initial binding of substrate to enzyme to form the Michaelis complex is accompanied by solvation changes that generate solvent deuterium isotope effects originating from hydrogen ion fractionation at multiple sites on the enzyme surface. (ii) From within the Michaelis complex, the active site serine attacks the carbonyl carbon of PNAA with general-base catalysis to form a substantially tetrahedral transition state enroute to the acyl-enzyme. (iii) Finally, deacylation occurs through a process involving a rate-limiting solvent isotope effect, generating conformational change of the acyl-enzyme that positions the carbonyl bond in a polarizing environment that is optimal for attack by water.

Super-complexes of adhesion GPCRs and neural guidance receptors

NASA Astrophysics Data System (ADS)

Jackson, Verity A.; Mehmood, Shahid; Chavent, Matthieu; Roversi, Pietro; Carrasquero, Maria; Del Toro, Daniel; Seyit-Bremer, Goenuel; Ranaivoson, Fanomezana M.; Comoletti, Davide; Sansom, Mark S. P.; Robinson, Carol V.; Klein, Rüdiger; Seiradake, Elena

2016-04-01

Latrophilin adhesion-GPCRs (Lphn1-3 or ADGRL1-3) and Unc5 cell guidance receptors (Unc5A-D) interact with FLRT proteins (FLRT1-3), thereby promoting cell adhesion and repulsion, respectively. How the three proteins interact and function simultaneously is poorly understood. We show that Unc5D interacts with FLRT2 in cis, controlling cell adhesion in response to externally presented Lphn3. The ectodomains of the three proteins bind cooperatively. Crystal structures of the ternary complex formed by the extracellular domains reveal that Lphn3 dimerizes when bound to FLRT2:Unc5, resulting in a stoichiometry of 1:1:2 (FLRT2:Unc5D:Lphn3). This 1:1:2 complex further dimerizes to form a larger `super-complex' (2:2:4), using a previously undescribed binding motif in the Unc5D TSP1 domain. Molecular dynamics simulations, point-directed mutagenesis and mass spectrometry demonstrate the stability and molecular properties of these complexes. Our data exemplify how receptors increase their functional repertoire by forming different context-dependent higher-order complexes.

Just Do It Yourself: Implementing 3D Printing in a Deployed Environment

DTIC Science & Technology

2017-04-01

This 3D model data can be stored for future manufacturing or manipulated, using software, to improve the parts’ design .8 3D manufactured parts can be...be developed and tested in a virtual environment, very quickly, and before manufacturing has commenced. Additionally, these 3D designs can be...capitalize on this innovative technology. Consequently, AM may offer the best hope for designing a reusable hypersonic weapon. Traditional manufacturing

[Three-dimensional 3D modeling: First applications in radioanatomy and interventional radiology under CT guidance].

PubMed

Aubry, S; Pousse, A; Sarliève, P; Laborie, L; Delabrousse, E; Kastler, B

2006-11-01

To model vertebrae in 3D to improve radioanatomic knowledge of the spine with the vascular and nerve environment and simulate CT-guided interventions. Vertebra acquisitions were made with multidetector CT. We developed segmentation software and specific viewer software using the Delphi programming environment. This segmentation software makes it possible to model 3D high-resolution segments of vertebrae and their environment from multidetector CT acquisitions. Then the specific viewer software provides multiplanar reconstructions of the CT volume and the possibility to select different 3D objects of interest. This software package improves radiologists' radioanatomic knowledge through a new 3D anatomy presentation. Furthermore, the possibility of inserting virtual 3D objects in the volume can simulate CT-guided intervention. The first volumetric radioanatomic software has been born. Furthermore, it simulates CT-guided intervention and consequently has the potential to facilitate learning interventions using CT guidance.

a Prompt Methodology to Georeference Complex Hypogea Environments

NASA Astrophysics Data System (ADS)

Troisi, S.; Baiocchi, V.; Del Pizzo, S.; Giannone, F.

2017-02-01

Actually complex underground structures and facilities occupy a wide space in our cities, most of them are often unsurveyed; cable duct, drainage system are not exception. Furthermore, several inspection operations are performed in critical air condition, that do not allow or make more difficult a conventional survey. In this scenario a prompt methodology to survey and georeferencing such facilities is often indispensable. A visual based approach was proposed in this paper; such methodology provides a 3D model of the environment and the path followed by the camera using the conventional photogrammetric/Structure from motion software tools. The key-role is played by the lens camera; indeed, a fisheye system was employed to obtain a very wide field of view (FOV) and therefore high overlapping among the frames. The camera geometry is in according to a forward motion along the axis camera. Consequently, to avoid instability of bundle adjustment algorithm a preliminary calibration of camera was carried out. A specific case study was reported and the accuracy achieved.

Complexes of plexin-A4 and plexin-D1 convey semaphorin-3C signals to induce cytoskeletal collapse in the absence of neuropilins.

PubMed

Smolkin, Tatyana; Nir-Zvi, Inbal; Duvshani, Nerri; Mumblat, Yelena; Kessler, Ofra; Neufeld, Gera

2018-05-04

Class-3 semaphorin guidance factors bind to receptor complexes containing neuropilin and plexin receptors. A semaphorin may bind to several receptor complexes containing somewhat different constituents, resulting in diverse effects on cell migration. U87MG glioblastoma cells express both neuropilins and the four class-A plexins. Here, we show that these cells respond to Sema3A or Sema3B by cytoskeletal collapse and cell contraction but fail to contract in response to Sema3C, Sema3D, Sema3G or Sema3E, even when class-A plexins are overexpressed in the cells. In contrast, expression of recombinant plexin-D1 enabled contraction in response to these semaphorins. Surprisingly, unlike Sema3D and Sema3G, Sema3C also induced the contraction and repulsion of plexin-D1-expressing U87MG cells in which both neuropilins were knocked out using CRISPR/Cas9. In the absence of neuropilins, the EC50 of Sema3C was 5.5 times higher, indicating that the neuropilins function as enhancers of plexin-D1-mediated Sema3C signaling but are not absolutely required for Sema3C signal transduction. Interestingly, in the absence of neuropilins, plexin-A4 formed complexes with plexin-D1, and was required in addition to plexin-D1 to enable Sema3C-induced signal transduction. © 2018. Published by The Company of Biologists Ltd.

Carboxylate ligands induced structural diversity of zinc(II) coordination polymers based on 3,6-bis(imidazol-1-yl)carbazole: Syntheses, structures and photocatalytic properties

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cheng, Hong-Jian, E-mail: hjcheng@cslg.cn; Tang, Hui-Xiang; Shen, Ya-Li

2015-12-15

Solvothermal reactions of Zn(NO{sub 3}){sub 2}·6H{sub 2}O with 3,6-bis(1-imidazolyl)carbazole (3,6-bmcz) and 1,4-benzenedicarboxylic acid (1,4-H{sub 2}bdc), p-phenylenediacetic acid (p-H{sub 2}pda), benzophenone-4,4-dicarboxylic acid (H{sub 2}bpda) afforded three coordination polymers [Zn(1,4-bdc)(3,6-bmcz)]{sub n} (1), {[Zn(p-pda)(3,6-bmcz)]·1.5H_2O}{sub n} (2) and {[Zn(bpda)(3,6-bmcz)]·0.25H_2O}{sub n} (3). Complexes 1–3 were characterized by elemental analysis, IR, powder X-ray diffraction, and single-crystal X-ray diffraction. Complex 1 shows 3D structure with 2D nets inclined polycatenation. Complexes 2 and 3 possess an extended 3D supramolecular architecture based on their respective 2D layers through hydrogen-bonding interactions and the π···π stacking interactions. The solid state luminescent and optical properties of 1–3 at ambient temperature were alsomore » investigated. A comparative study on their photocatalytic activity toward the degradation of methylene blue in polluted water was explored. - Graphical abstract: Reactions of Zn(NO{sub 3}){sub 2} and 3,6-(1-imidazolyl)carbazole with 1,4-benzenedicarboxylic acid, p-phenylenediacetic acid or benzophenone-4,4-dicarboxylic acid afforded three coordination polymers with different topologies and photocatalytic activity. - Highlights: • Reactions of 1,4-H{sub 2}bdc, p-H{sub 2}pda or H{sub 2}bpda with 3,6-bmcz and Zn(II) gave three CPs. • Complex 1 is a 3D entanglement. • Complex 2 or 3 is a 3D supramolecular structure based on different 2D layers. • Complex 2 exhibited good catalytic activity of methylene blue photodegradation.« less

Bioprinting Perfusion-Enabled Liver Equivalents for Advanced Organ-on-a-Chip Applications.

PubMed

Grix, Tobias; Ruppelt, Alicia; Thomas, Alexander; Amler, Anna-Klara; Noichl, Benjamin P; Lauster, Roland; Kloke, Lutz

2018-03-22

Many tissue models have been developed to mimic liver-specific functions for metabolic and toxin conversion in in vitro assays. Most models represent a 2D environment rather than a complex 3D structure similar to native tissue. To overcome this issue, spheroid cultures have become the gold standard in tissue engineering. Unfortunately, spheroids are limited in size due to diffusion barriers in their dense structures, limiting nutrient and oxygen supply. Recent developments in bioprinting techniques have enabled us to engineer complex 3D structures with perfusion-enabled channel systems to ensure nutritional supply within larger, densely-populated tissue models. In this study, we present a proof-of-concept for the feasibility of bioprinting a liver organoid by combining HepaRG and human stellate cells in a stereolithographic printing approach, and show basic characterization under static cultivation conditions. Using standard tissue engineering analytics, such as immunohistology and qPCR, we found higher albumin and cytochrome P 450 3A4 (CYP3A4) expression in bioprinted liver tissues compared to monolayer controls over a two-week cultivation period. In addition, the expression of tight junctions, liver-specific bile transporter multidrug resistance-associated protein 2 (MRP2), and overall metabolism (glucose, lactate, lactate dehydrogenase (LDH)) were found to be stable. Furthermore, we provide evidence for the perfusability of the organoids' intrinsic channel system. These results motivate new approaches and further development in liver tissue engineering for advanced organ-on-a-chip applications and pharmaceutical developments.

Cd(II)-coordination polymers based on tetracarboxylic acid and diverse bis(imidazole) ligands: Synthesis, structural diversity and photoluminescence properties

DOE Office of Scientific and Technical Information (OSTI.GOV)

Arıcı, Mürsel, E-mail: marici@ogu.edu.tr; Yeşilel, Okan Zafer; Taş, Murat

Three new Cd(II)-coordination polymers, namely, ([Cd{sub 2}(μ{sub 6}-ao{sub 2}btc)(μ-1,5-bipe){sub 2}]·2H{sub 2}O){sub n} (1), ([Cd{sub 2}(μ{sub 6}-ao{sub 2}btc)(μ-1,4-bix){sub 2}]{sub n}·2DMF) (2) and ([Cd{sub 2}(μ{sub 8}-abtc)(μ-1,4-betix)]·DMF·H{sub 2}O){sub n} (3) (ao{sub 2}btc=di-oxygenated form of 3,3′,5,5′-azobenzenetetracarboxylate, 1,5-bipe: 1,5-bis(imidazol-1yl)pentane, 1,4-bix=1,4-bis(imidazol-1ylmethyl)benzene, 1,4-betix=1,4-bis(2-ethylimidazol-1ylmethyl)benzene) were synthesized with 3,3′,5,5′-azobenzenetetracarboxylic acid and flexible, semi-flexible and semi-flexible substituted bis(imidazole) linkers. They were characterized by IR spectroscopy, elemental analysis, single-crystal X-ray diffraction, powder X-ray diffractions (PXRD) and thermal analyses (TG/DTA). Complexes 1–3 exhibited structural diversities depending on flexible, semi-flexible and semi-flexible substituted bis(imidazole) ligands. Complex 1 was 2D structure with 3,6L18 topology. Complex 2 had a 3D pillar-layered framework with the raremore » sqc27 topology. When semi-flexible substituted bis(imidazole) linker was used, 3D framework of complex 3 was obtained with the paddlewheel Cd{sub 2}(CO{sub 2}){sub 4}-type binuclear SBU. Moreover, thermal and photoluminescence properties of the complexes were determined in detailed. - Graphical abstract: In this study, three novel Cd(II)-coordination polymers were synthesized with 3,3′,5,5′-azobenzenetetracarboxylic acid and flexible, semi-flexible and semi-flexible substituted bis(imidazole) linkers. They were characterized by IR spectroscopy, elemental analysis, single-crystal X-ray diffraction, powder X-ray diffractions (PXRD) and thermal analyses (TG/DTA). Complexes 1–3 exhibited structural diversities depending on flexible, semi-flexible and semi-flexible substituted bis(imidazole) ligands. Complex 1 was 2D structure with 3,6L18 topology. Complex 2 had a 3D pillar-layered framework with the rare sqc27 topology. When semi-flexible substituted bis(imidazole) linker was used, 3D framework of complex 3 was obtained with the paddlewheel Cd{sub 2}(CO{sub 2}){sub 4}-type binuclear SBU. - Highlights: • Three new Cd(II)-coordination polymers with azobenzenetetracarboxylic acid and diverse bis(imidazole) linkers. • Complex 1 is 2D structure with 3,6L18 topology. • 3D pillar-layered framework of 2 with the rare sqc27 topology. • 3D framework of 3 with the paddlewheel Cd{sub 2}(CO{sub 2}){sub 4}-type SBU.« less

MO-G-BRF-01: BEST IN PHYSICS (JOINT IMAGING-THERAPY) - Sensitivity of PET-Based Texture Features to Respiratory Motion in Non-Small Cell Lung Cancer (NSCLC)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yip, S; Aerts, H; Berbeco, R

2014-06-15

Purpose: PET-based texture features are used to quantify tumor heterogeneity due to their predictive power in treatment outcome. We investigated the sensitivity of texture features to tumor motion by comparing whole body (3D) and respiratory-gated (4D) PET imaging. Methods: Twenty-six patients (34 lesions) received 3D and 4D [F-18]FDG-PET scans before chemo-radiotherapy. The acquired 4D data were retrospectively binned into five breathing phases to create the 4D image sequence. Four texture features (Coarseness, Contrast, Busyness, and Complexity) were computed within the the physician-defined tumor volume. The relative difference (δ) in each measure between the 3D- and 4D-PET imaging was calculated. Wilcoxonmore » signed-rank test (p<0.01) was used to determine if δ was significantly different from zero. Coefficient of variation (CV) was used to determine the variability in the texture features between all 4D-PET phases. Pearson correlation coefficient was used to investigate the impact of tumor size and motion amplitude on δ. Results: Significant differences (p<<0.01) between 3D and 4D imaging were found for Coarseness, Busyness, and Complexity. The difference for Contrast was not significant (p>0.24). 4D-PET increased Busyness (∼20%) and Complexity (∼20%), and decreased Coarseness (∼10%) and Contrast (∼5%) compared to 3D-PET. Nearly negligible variability (CV=3.9%) was found between the 4D phase bins for Coarseness and Complexity. Moderate variability was found for Contrast and Busyness (CV∼10%). Poor correlation was found between the tumor volume and δ for the texture features (R=−0.34−0.34). Motion amplitude had moderate impact on δ for Contrast and Busyness (R=−0.64− 0.54) and no impact for Coarseness and Complexity (R=−0.29−0.17). Conclusion: Substantial differences in textures were found between 3D and 4D-PET imaging. Moreover, the variability between phase bins for Coarseness and Complexity was negligible, suggesting that similar quantification can be obtained from all phases. Texture features, blurred out by respiratory motion during 3D-PET acquisition, can be better resolved by 4D-PET imaging with any phase.« less

Development of Three-Dimensional Completion of Complex Objects

ERIC Educational Resources Information Center

Soska, Kasey C.; Johnson, Scott P.

2013-01-01

Three-dimensional (3D) object completion, the ability to perceive the backs of objects seen from a single viewpoint, emerges at around 6 months of age. Yet, only relatively simple 3D objects have been used in assessing its development. This study examined infants' 3D object completion when presented with more complex stimuli. Infants…

New coordination polymers from 1D chain, 2D layer to 3D framework constructed from 1,2-phenylenediacetic acid and 1,3-bis(4-pyridyl)propane flexible ligands

NASA Astrophysics Data System (ADS)

Xin, Ling-Yun; Liu, Guang-Zhen; Wang, Li-Ya

2011-06-01

The hydrothermal reactions of Cd, Zn, or Cu(II) acetate salts with H 2PHDA and BPP flexible ligands afford three new coordination polymers, including [Cd(PHDA)(BPP)(H 2O)] n(1), [Zn(PHDA)(BPP)] n(2), and [Cu 2(PHDA) 2(BPP)] n(3) (H 2PHDA=1,2-phenylenediacetic acid, BPP=1,3-bis(4-pyridyl)propane). The single-crystal X-ray diffractions reveal that all three complexes feature various metal carboxylate subunits extended further by the BPP ligands to form a diverse range of structures, displaying a remarked structural sensitivity to metal(II) cation. Complex 1 containing PHDA-bridged binuclear cadmium generates 1D double-stranded chain, complex 2 results in 2D→2D interpenetrated (4,4) grids, and complex 3 displays a 3D self-penetrated framework with 4 86 68 rob topology. In addition, fluorescent analyses show that both 1 and 2 exhibit intense blue-violet photoluminescence in the solid state.

L-edge sum rule analysis on 3d transition metal sites: from d10 to d0 and towards application to extremely dilute metallo-enzymes.

PubMed

Wang, Hongxin; Friedrich, Stephan; Li, Lei; Mao, Ziliang; Ge, Pinghua; Balasubramanian, Mahalingam; Patil, Daulat S

2018-03-28

According to L-edge sum rules, the number of 3d vacancies at a transition metal site is directly proportional to the integrated intensity of the L-edge X-ray absorption spectrum (XAS) for the corresponding metal complex. In this study, the numbers of 3d holes are characterized quantitatively or semi-quantitatively for a series of manganese (Mn) and nickel (Ni) complexes, including the electron configurations 3d 10 → 3d 0 . In addition, extremely dilute (<0.1% wt/wt) Ni enzymes were examined by two different approaches: (1) by using a high resolution superconducting tunnel junction X-ray detector to obtain XAS spectra with a very high signal-to-noise ratio, especially in the non-variant edge jump region; and (2) by adding an inert tracer to the sample that provides a prominent spectral feature to replace the weak edge jump for intensity normalization. In this publication, we present for the first time: (1) L-edge sum rule analysis for a series of Mn and Ni complexes that include electron configurations from an open shell 3d 0 to a closed shell 3d 10 ; (2) a systematic analysis on the uncertainties, especially on that from the edge jump, which was missing in all previous reports; (3) a clearly-resolved edge jump between pre-L 3 and post-L 2 regions from an extremely dilute sample; (4) an evaluation of an alternative normalization standard for L-edge sum rule analysis. XAS from two copper (Cu) proteins measured using a conventional semiconductor X-ray detector are also repeated as bridges between Ni complexes and dilute Ni enzymes. The differences between measuring 1% Cu enzymes and measuring <0.1% Ni enzymes are compared and discussed. This study extends L-edge sum rule analysis to virtually any 3d metal complex and any dilute biological samples that contain 3d metals.

The distinct roles of the nucleus and nucleus-cytoskeleton connections in three-dimensional cell migration

PubMed Central

Khatau, Shyam B.; Bloom, Ryan J.; Bajpai, Saumendra; Razafsky, David; Zang, Shu; Giri, Anjil; Wu, Pei-Hsun; Marchand, Jorge; Celedon, Alfredo; Hale, Christopher M.; Sun, Sean X.; Hodzic, Didier; Wirtz, Denis

2012-01-01

Cells often migrate in vivo in an extracellular matrix that is intrinsically three-dimensional (3D) and the role of actin filament architecture in 3D cell migration is less well understood. Here we show that, while recently identified linkers of nucleoskeleton to cytoskeleton (LINC) complexes play a minimal role in conventional 2D migration, they play a critical role in regulating the organization of a subset of actin filament bundles – the perinuclear actin cap - connected to the nucleus through Nesprin2giant and Nesprin3 in cells in 3D collagen I matrix. Actin cap fibers prolong the nucleus and mediate the formation of pseudopodial protrusions, which drive matrix traction and 3D cell migration. Disruption of LINC complexes disorganizes the actin cap, which impairs 3D cell migration. A simple mechanical model explains why LINC complexes and the perinuclear actin cap are essential in 3D migration by providing mechanical support to the formation of pseudopodial protrusions. PMID:22761994

Hydrogen and oxygen isotope constraints on hydrothermal alteration of the Trinity peridotite, Klamath Mountains, California

USGS Publications Warehouse

Liakhovitch, V.; Quick, J.E.; Gregory, R.T.

2005-01-01

The Trinity peridotite represents a rare opportunity to examine a relatively fertile plagioclase peridotite that was exhumed and later subjected to intrusive events in a seafloor environment, followed by its emplacement and incorporation into a continent. Over 250 stable isotopic determinations on whole rocks and minerals elucidate the hydrothermal evolution of the Trinity complex. All three serpentine polymorphs are present in the Trinity peridotite; these separate on the basis of their ??D values: antigorite, -46 < ??D < -82??? and lizardite and chrysotile, -90 < ??D < -106 and -110 < ??D < -136???, respectively. Antigorite coexists with chlorite, talc, and tremolite in contact aureole assemblages associated with Silurian/Devonian gabbroic plutons. Lizardite and chrysotile alteration carries a meteoric signature, which suggests association with post-emplacement serpentinization, or overprinting of earlier low-temperature seafloor serpentinization. Regionally, contours of ??D values exhibit bull's-eye patterns associated with the gabbroic plutons, with ??D maxima coinciding with the blackwall alteration at the margins on the plutons. In contrast to the hydrogen isotope behavior, oxygen isotope values of the three polymorphs are indistinguishable, spanning the range 5.3 < ??18O< 7.5, and suggesting low integrated fluid fluxes and strongly 18O-shifted fluids. Inferred primary ?? 18O values for peridotite, gabbro, and late Mesozoic granodiorite indicate a progressive 18O enrichment with time for the source regions of the rocks. These isotopic signatures are consistent with the geology, petrochemistry, and geochronology of the Trinity massif, which indicate the following history: (1) lithospheric emplacement and cooling of the peridotite in an oceanic environment ??? 472 Ma; (2) intrusion of gabbroic plutons into cold peridotite in an arc environment between 435 and 404 Ma; and finally (3) intrusion of felsic plutons between 171 and 127 Ma, long after the peridotite was incorporated into the continental crust. Copyright ?? 2005 by V. H. Winston & Son, Inc. All rights reserved.

3D Printing: 3D Printing of Conductive Complex Structures with In Situ Generation of Silver Nanoparticles (Adv. Mater. 19/2016).

PubMed

Fantino, Erika; Chiappone, Annalisa; Roppolo, Ignazio; Manfredi, Diego; Bongiovanni, Roberta; Pirri, Candido Fabrizio; Calignano, Flaviana

2016-05-01

On page 3712, E. Fantino, A. Chiappone, and co-workers fabricate conductive 3D hybrid structures by coupling the photo-reduction of metal precursors with 3D printing technology. The generated structures consist of metal nanoparticles embedded in a polymer matrix shaped into complex multilayered architectures. 3D conductive structures are fabricated with a digital light-processing printer incorporating silver salt into photocurable formulations. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Synthesis, structure, photoluminescence and antitumour activity of zinc complex based on 2-(2-(1H-benzo-[d]imidazol-2-yl)benzyl)-1H-benzo-[d]imidazole

NASA Astrophysics Data System (ADS)

Che, Zhijian; Wang, Shaoxiang; Liu, Shenggui; Li, Guobi; Wu, Qiting; Lin, Chunyu; Kong, Linglang; Wang, Sheng

2015-01-01

A new complex [Zn(bbb)Cl2]·DMF, where bbb is 2-(2-(1H-benzo[d]imidazol-2-yl)benzyl)-1H-benzo[d]imidazole, was synthesized and characterized by element analysis, 1H NMR and X-ray single crystal structure analyses. For complex: crystal system, triclinic, space group, P-1, a = 9.4661(13), b = 10.3534(14), c = 13.0025(18) Å, α = 73.477(2), β = 80.743(2), γ = 88.658(2)°, V = 1205.5(3) Å3, Z = 2. In this complex, the Zn2+ distorted tetrahedron geometry is coordinated by two nitrogen atoms from 2-(2-(1H-benzo[d]imidazol-2-yl)benzyl)-1H-benzo[d]imidazole and two Cl-. The complex emits yellow green luminescence with the maximal emission peak at 550 nm in DMF solution. The complex exhibits inhibition on the growth of Eca109 cancer cell with IC50 value of 8.9 ± 1.1 μM, which was lower than that of cisplatin (14.3 ± 1.4 μM). This complex has potential application in treatment of esophageal cancer.

Secondary interactions in thallium(I) coordination, [Tl 2(DBM) 2] n, DBM - = 1,3-diphenylpropane-1,3-dionate (dibenzoylmethanide)

NASA Astrophysics Data System (ADS)

Askarinejad, Azadeh; Morsali, Ali; Zhu, Long-Guan

2006-05-01

The Tl I complex of 1,3-diphenylpropane-1,3-dionate (dibenzoylmethanide, DBM -), [Tl 2(DBM) 2] n, has been synthesized and characterized. The single-crystal X-ray data show there are two different Tl environments. One type of Tl-atom in the TlO 4C 6Tl 2 environment is twelve-coordinated, with two weak Tl⋯Tl and hexahapto ( η) interactions, TlC 6. The other type of Tl-atom in the TlO 4C 2Tl 2 units is eight-coordinated, with two weak Tl⋯Tl and dihapto ( η) interactions, TlC 2. The dimeric units [Tl 2(DBM) 2] linked through Tl⋯Tl and polyhapto interactions, TlC 6 and TlC 2, and produce the 1D polymeric chains. Comparison with the analogous Pb(II) compound indicates that Tl I may also act as both a Lewis acid and a Lewis base.

1D and 3D anthropometric data application on public transport vehicle layout and on oil and gas laboratories work environment design.

PubMed

Pastura, F C H; Guimarães, C P; Zamberlan, M C P; Cid, G L; Santos, V S; Streit, P; Paranhos, A G; Cobbe, R T; Cobbe, K T; Batista, D S

2012-01-01

The goal of this paper is to present 1D and 3D anthropometric data applied to two distinct design situations: one related to the interior layout of a public transport vehicle and another one related to oil and gas laboratories work environment design. On this study, the 1D anthropometric data were extracted from the Brazilian anthropometric database developed by INT and the 3D anthropometric data were obtained using a Cyberware 3D whole body scanner. A second purpose of this paper is to present the 3D human scanning data as a tool that can help designers on decision making.

Virtual Representations in 3D Learning Environments

ERIC Educational Resources Information Center

Shonfeld, Miri; Kritz, Miki

2013-01-01

This research explores the extent to which virtual worlds can serve as online collaborative learning environments for students by increasing social presence and engagement. 3D environments enable learning, which simulates face-to-face encounters while retaining the advantages of online learning. Students in Education departments created avatars…

Nuclei of dwarf spheroidal galaxies KKs 3 and ESO 269-66 and their counterparts in our Galaxy

NASA Astrophysics Data System (ADS)

Sharina, M. E.; Shimansky, V. V.; Kniazev, A. Y.

2017-10-01

We present the analysis of medium-resolution spectra obtained at the Southern African Large Telescope for nuclear globular clusters (GCs) in two dwarf spheroidal galaxies (dSphs). The galaxies have similar star formation histories, but they are situated in completely different environments. ESO 269-66 is a close neighbour of the giant S0 NGC 5128. KKs 3 is one of the few truly isolated dSphs within 10 Mpc. We estimate the helium abundance Y = 0.3, age = 12.6 ± 1 Gyr, [Fe/H] = -1.5, -1.55 ± 0.2 dex, and abundances of C, N, Mg, Ca, Ti, and Cr for the nuclei of ESO 269-66 and KKs 3. Our surface photometry results using Hubble Space Telescope images yield the half-light radius of the cluster in KKs 3, rh = 4.8 ± 0.2 pc. We demonstrate the similarities of medium-resolution spectra, ages, chemical compositions, and structure for GCs in ESO 269-66 and KKs 3 and for several massive Galactic GCs with [Fe/H] ∼ -1.6 dex. All Galactic GCs posses Extended Blue Horizontal Branches and multiple stellar populations. Five of the selected Galactic objects are iron-complex GCs. Our results indicate that the sample GCs observed now in different environments had similar conditions of their formation ∼1 Gyr after the Big Bang.

Multi and mixed 3D-printing of graphene-hydroxyapatite hybrid materials for complex tissue engineering.

PubMed

Jakus, Adam E; Shah, Ramille N

2017-01-01

With the emergence of three-dimensional (3D)-printing (3DP) as a vital tool in tissue engineering and medicine, there is an ever growing need to develop new biomaterials that can be 3D-printed and also emulate the compositional, structural, and functional complexities of human tissues and organs. In this work, we probe the 3D-printable biomaterials spectrum by combining two recently established functional 3D-printable particle-laden biomaterial inks: one that contains hydroxyapatite microspheres (hyperelastic bone, HB) and another that contains graphene nanoflakes (3D-graphene, 3DG). We demonstrate that not only can these distinct, osteogenic, and neurogenic inks be co-3D-printed to create complex, multimaterial constructs, but that composite inks of HB and 3DG can also be synthesized. Specifically, the printability, microstructural, mechanical, electrical, and biological properties of a hybrid material comprised of 1:1 HA:graphene by volume is investigated. The resulting HB-3DG hybrid exhibits mixed characteristics of the two distinct systems, while maintaining 3D-printability, electrical conductivity, and flexibility. In vitro assessment of HB-3DG using mesenchymal stem cells demonstrates the hybrid material supports cell viability and proliferation, as well as significantly upregulates both osteogenic and neurogenic gene expression over 14 days. This work ultimately demonstrates a significant step forward towards being able to 3D-print graded, multicompositional, and multifunctional constructs from hybrid inks for complex composite tissue engineering. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 274-283, 2017. © 2016 Wiley Periodicals, Inc.

A recipe for consistent 3D management of velocity data and time-depth conversion using Vel-IO 3D

NASA Astrophysics Data System (ADS)

Maesano, Francesco E.; D'Ambrogi, Chiara

2017-04-01

3D geological model production and related basin analyses need large and consistent seismic dataset and hopefully well logs to support correlation and calibration; the workflow and tools used to manage and integrate different type of data control the soundness of the final 3D model. Even though seismic interpretation is a basic early step in such workflow, the most critical step to obtain a comprehensive 3D model useful for further analyses is represented by the construction of an effective 3D velocity model and a well constrained time-depth conversion. We present a complex workflow that includes comprehensive management of large seismic dataset and velocity data, the construction of a 3D instantaneous multilayer-cake velocity model, the time-depth conversion of highly heterogeneous geological framework, including both depositional and structural complexities. The core of the workflow is the construction of the 3D velocity model using Vel-IO 3D tool (Maesano and D'Ambrogi, 2017; https://github.com/framae80/Vel-IO3D) that is composed by the following three scripts, written in Python 2.7.11 under ArcGIS ArcPy environment: i) the 3D instantaneous velocity model builder creates a preliminary 3D instantaneous velocity model using key horizons in time domain and velocity data obtained from the analysis of well and pseudo-well logs. The script applies spatial interpolation to the velocity parameters and calculates the value of depth of each point on each horizon bounding the layer-cake velocity model. ii) the velocity model optimizer improves the consistency of the velocity model by adding new velocity data indirectly derived from measured depths, thus reducing the geometrical uncertainties in the areas located far from the original velocity data. iii) the time-depth converter runs the time-depth conversion of any object located inside the 3D velocity model The Vel-IO 3D tool allows one to create 3D geological models consistent with the primary geological constraints (e.g. depth of the markers on wells). The workflow and Vel-IO 3D tool have been developed and tested for the construction of the 3D geological model of a flat region, 5700 km2 in area, located in the central part of the Po Plain (Northern Italy) in the frame of the European funded Project GeoMol. The study area was covered by a dense dataset of seismic lines (ca. 12000 km) and exploration wells (130 drilling), mainly deriving from oil and gas exploration activities. The interpretation of the seismic dataset leads to the construction of a 3D model in time domain that has been depth converted using Vel-IO 3D, with a 4 layer-cake 3D instantaneous velocity model. The resulting final 3D geological model, composed of 15 horizons and 150 faults, has been used for basin analysis at regional scale, for geothermal assessment, and for the update of the seismotectonic knowledge of the Po Plain. The Vel-IO 3D has been further used for the depth conversion of the accretionary prism of the Calabrian subduction (Southern Italy) and for a basin scale analysis of the Po Plain Plio-Pleistocene evolution. Maesano F.E. and D'Ambrogi C., (2017), Computers and Geosciences, doi: 10.1016/j.cageo.2016.11.013 Vel-IO 3D is available at: https://github.com/framae80/Vel-IO3D

User Control and Task Authenticity for Spatial Learning in 3D Environments

ERIC Educational Resources Information Center

Dalgarno, Barney; Harper, Barry

2004-01-01

This paper describes two empirical studies which investigated the importance for spatial learning of view control and object manipulation within 3D environments. A 3D virtual chemistry laboratory was used as the research instrument. Subjects, who were university undergraduate students (34 in the first study and 80 in the second study), undertook…

Educational Visualizations in 3D Collaborative Virtual Environments: A Methodology

ERIC Educational Resources Information Center

Fominykh, Mikhail; Prasolova-Forland, Ekaterina

2012-01-01

Purpose: Collaborative virtual environments (CVEs) have become increasingly popular in educational settings and the role of 3D content is becoming more and more important. Still, there are many challenges in this area, such as lack of empirical studies that provide design for educational activities in 3D CVEs and lack of norms of how to support…

3D Virtual Learning Environments in Education: A Meta-Review

ERIC Educational Resources Information Center

Reisoglu, I.; Topu, B.; Yilmaz, R.; Karakus Yilmaz, T.; Göktas, Y.

2017-01-01

The aim of this study is to investigate recent empirical research studies about 3D virtual learning environments. A total of 167 empirical studies that involve the use of 3D virtual worlds in education were examined by meta-review. Our findings show that the "Second Life" platform has been frequently used in studies. Among the reviewed…

Intelligent mobility research for robotic locomotion in complex terrain

NASA Astrophysics Data System (ADS)

Trentini, Michael; Beckman, Blake; Digney, Bruce; Vincent, Isabelle; Ricard, Benoit

2006-05-01

The objective of the Autonomous Intelligent Systems Section of Defence R&D Canada - Suffield is best described by its mission statement, which is "to augment soldiers and combat systems by developing and demonstrating practical, cost effective, autonomous intelligent systems capable of completing military missions in complex operating environments." The mobility requirement for ground-based mobile systems operating in urban settings must increase significantly if robotic technology is to augment human efforts in these roles and environments. The intelligence required for autonomous systems to operate in complex environments demands advances in many fields of robotics. This has resulted in large bodies of research in areas of perception, world representation, and navigation, but the problem of locomotion in complex terrain has largely been ignored. In order to achieve its objective, the Autonomous Intelligent Systems Section is pursuing research that explores the use of intelligent mobility algorithms designed to improve robot mobility. Intelligent mobility uses sensing, control, and learning algorithms to extract measured variables from the world, control vehicle dynamics, and learn by experience. These algorithms seek to exploit available world representations of the environment and the inherent dexterity of the robot to allow the vehicle to interact with its surroundings and produce locomotion in complex terrain. The primary focus of the paper is to present the intelligent mobility research within the framework of the research methodology, plan and direction defined at Defence R&D Canada - Suffield. It discusses the progress and future direction of intelligent mobility research and presents the research tools, topics, and plans to address this critical research gap. This research will create effective intelligence to improve the mobility of ground-based mobile systems operating in urban settings to assist the Canadian Forces in their future urban operations.

3-D surface reconstruction of patient specific anatomic data using a pre-specified number of polygons.

PubMed

Aharon, S; Robb, R A

1997-01-01

Virtual reality environments provide highly interactive, natural control of the visualization process, significantly enhancing the scientific value of the data produced by medical imaging systems. Due to the computational and real time display update requirements of virtual reality interfaces, however, the complexity of organ and tissue surfaces which can be displayed is limited. In this paper, we present a new algorithm for the production of a polygonal surface containing a pre-specified number of polygons from patient or subject specific volumetric image data. The advantage of this new algorithm is that it effectively tiles complex structures with a specified number of polygons selected to optimize the trade-off between surface detail and real-time display rates.

Mispairs with Watson-Crick base-pair geometry observed in ternary complexes of an RB69 DNA polymerase variant.

PubMed

Xia, Shuangluo; Konigsberg, William H

2014-04-01

Recent structures of DNA polymerase complexes with dGMPCPP/dT and dCTP/dA mispairs at the insertion site have shown that they adopt Watson-Crick geometry in the presence of Mn(2+) indicating that the tautomeric or ionization state of the base has changed. To see whether the tautomeric or ionization state of base-pair could be affected by its microenvironment, we determined 10 structures of an RB69 DNA polymerase quadruple mutant with dG/dT or dT/dG mispairs at position n-1 to n-5 of the Primer/Template duplex. Different shapes of the mispairs, including Watson-Crick geometry, have been observed, strongly suggesting that the local environment of base-pairs plays an important role in their tautomeric or ionization states. © 2014 The Protein Society.

EXPLORING ENVIRONMENTAL DATA IN A HIGHLY IMMERSIVE VIRTUAL REALITY ENVIRONMENT

EPA Science Inventory

Geography inherently fills a 3D space and yet we struggle with displaying geography using, primaarily, 2D display devices. Virtual environments offer a more realistically-dimensioned display space and this is being realized in the expanding area of research on 3D Geographic Infor...

Tuning the Electronic Structure of Fe(II) Polypyridines via Donor Atom and Ligand Scaffold Modifications: A Computational Study.

PubMed

Bowman, David N; Bondarev, Alexey; Mukherjee, Sriparna; Jakubikova, Elena

2015-09-08

Fe(II) polypyridines are an important class of pseudo-octahedral metal complexes known for their potential applications in molecular electronic switches, data storage and display devices, sensors, and dye-sensitized solar cells. Fe(II) polypyridines have a d(6) electronic configuration and pseudo-octahedral geometry and can therefore possess either a high-spin (quintet) or a low-spin (singlet) ground state. In this study, we investigate a series of complexes based on [Fe(tpy)2](2+) (tpy = 2,2';6',2″-terpyridine) and [Fe(dcpp)2](2+) (dcpp = 2,6-bis(2-carboxypyridyl)pyridine). The ligand field strength in these complexes is systematically tuned by replacing the central pyridine with five-membered (N-heterocyclic carbene, pyrrole, furan) or six-membered (aryl, thiazine-1,1-dioxide, 4-pyrone) moieties. To determine the impact of ligand substitutions on the relative energies of metal-centered states, the singlet, triplet, and quintet states of the Fe(II) complexes were optimized in water (PCM) using density functional theory at the B3LYP+D2 level with 6-311G* (nonmetals) and SDD (Fe) basis sets. It was found that the dcpp ligand scaffold allows for a more ideal octahedral coordination environment in comparison to the tpy ligand scaffold. The presence of six-membered central rings also allows for a more ideally octahedral coordination environment relative to five-membered central rings, regardless of the ligand scaffold. We find that the ligand field strength in the Fe(II) polypyridines can be tuned by altering the donor atom identity, with C donor atoms providing the strongest ligand field.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Haghighat, A.; Sjoden, G.E.; Wagner, J.C.

In the past 10 yr, the Penn State Transport Theory Group (PSTTG) has concentrated its efforts on developing accurate and efficient particle transport codes to address increasing needs for efficient and accurate simulation of nuclear systems. The PSTTG's efforts have primarily focused on shielding applications that are generally treated using multigroup, multidimensional, discrete ordinates (S{sub n}) deterministic and/or statistical Monte Carlo methods. The difficulty with the existing public codes is that they require significant (impractical) computation time for simulation of complex three-dimensional (3-D) problems. For the S{sub n} codes, the large memory requirements are handled through the use of scratchmore » files (i.e., read-from and write-to-disk) that significantly increases the necessary execution time. Further, the lack of flexible features and/or utilities for preparing input and processing output makes these codes difficult to use. The Monte Carlo method becomes impractical because variance reduction (VR) methods have to be used, and normally determination of the necessary parameters for the VR methods is very difficult and time consuming for a complex 3-D problem. For the deterministic method, the authors have developed the 3-D parallel PENTRAN (Parallel Environment Neutral-particle TRANsport) code system that, in addition to a parallel 3-D S{sub n} solver, includes pre- and postprocessing utilities. PENTRAN provides for full phase-space decomposition, memory partitioning, and parallel input/output to provide the capability of solving large problems in a relatively short time. Besides having a modular parallel structure, PENTRAN has several unique new formulations and features that are necessary for achieving high parallel performance. For the Monte Carlo method, the major difficulty currently facing most users is the selection of an effective VR method and its associated parameters. For complex problems, generally, this process is very time consuming and may be complicated due to the possibility of biasing the results. In an attempt to eliminate this problem, the authors have developed the A{sup 3}MCNP (automated adjoint accelerated MCNP) code that automatically prepares parameters for source and transport biasing within a weight-window VR approach based on the S{sub n} adjoint function. A{sup 3}MCNP prepares the necessary input files for performing multigroup, 3-D adjoint S{sub n} calculations using TORT.« less

Analysis of EEG signals regularity in adults during video game play in 2D and 3D.

PubMed

Khairuddin, Hamizah R; Malik, Aamir S; Mumtaz, Wajid; Kamel, Nidal; Xia, Likun

2013-01-01

Video games have long been part of the entertainment industry. Nonetheless, it is not well known how video games can affect us with the advancement of 3D technology. The purpose of this study is to investigate the EEG signals regularity when playing video games in 2D and 3D modes. A total of 29 healthy subjects (24 male, 5 female) with mean age of 21.79 (1.63) years participated. Subjects were asked to play a car racing video game in three different modes (2D, 3D passive and 3D active). In 3D passive mode, subjects needed to wear a passive polarized glasses (cinema type) while for 3D active, an active shutter glasses was used. Scalp EEG data was recorded during game play using 19-channel EEG machine and linked ear was used as reference. After data were pre-processed, the signal irregularity for all conditions was computed. Two parameters were used to measure signal complexity for time series data: i) Hjorth-Complexity and ii) Composite Permutation Entropy Index (CPEI). Based on these two parameters, our results showed that the complexity level increased from eyes closed to eyes open condition; and further increased in the case of 3D as compared to 2D game play.

Advances in animal ecology from 3D ecosystem mapping with LiDAR

NASA Astrophysics Data System (ADS)

Davies, A.; Asner, G. P.

2015-12-01

The advent and recent advances of Light Detection and Ranging (LiDAR) have enabled accurate measurement of 3D ecosystem structure. Although the use of LiDAR data is widespread in vegetation science, it has only recently (< 14 years) been applied to animal ecology. Despite such recent application, LiDAR has enabled new insights in the field and revealed the fundamental importance of 3D ecosystem structure for animals. We reviewed the studies to date that have used LiDAR in animal ecology, synthesising the insights gained. Structural heterogeneity is most conducive to increased animal richness and abundance, and increased complexity of vertical vegetation structure is more positively influential than traditionally measured canopy cover, which produces mixed results. However, different taxonomic groups interact with a variety of 3D canopy traits and some groups with 3D topography. LiDAR technology can be applied to animal ecology studies in a wide variety of environments to answer an impressive array of questions. Drawing on case studies from vastly different groups, termites and lions, we further demonstrate the applicability of LiDAR and highlight new understanding, ranging from habitat preference to predator-prey interactions, that would not have been possible from studies restricted to field based methods. We conclude with discussion of how future studies will benefit by using LiDAR to consider 3D habitat effects in a wider variety of ecosystems and with more taxa to develop a better understanding of animal dynamics.

Numerical simulation of deformation and failure processes of a complex technical object under impact loading

NASA Astrophysics Data System (ADS)

Kraus, E. I.; Shabalin, I. I.; Shabalin, T. I.

2018-04-01

The main points of development of numerical tools for simulation of deformation and failure of complex technical objects under nonstationary conditions of extreme loading are presented. The possibility of extending the dynamic method for construction of difference grids to the 3D case is shown. A 3D realization of discrete-continuum approach to the deformation and failure of complex technical objects is carried out. The efficiency of the existing software package for 3D modelling is shown.

Optical Trapping and Manipulation in the Single- and Many-Body Limits

NASA Astrophysics Data System (ADS)

Spalding, Gabriel

2007-03-01

Analysis of optical dipole/scattering forces can be done at a variety of levels, some of which are appropriate to the undergraduate curriculum. The addition of simple holographic techniques has extended the basic capabilities of optical tweezing, making it a more viable tool for the assembly of micro-systems and organization of specimens into user-defined structures. In 2D, we have demonstrated an approach that allows optical forces alone to assemble microparticles over macroscopic areas. 3D structures pose greater challenges, but also significant opportunities. Our early efforts at filling a 3D lattice of optical traps led to an appreciation for the dynamics of injected microparticle streams, which yield a surprisingly successful method of sorting or re- routing within microfludic environments. We will discuss the status of efforts using optical trapping to create static many-body structures (both simple and complex), as well as recent results on dynamic interactions. At the same time, some of these techniques have clear pedagogical value, as will be emphasized.

Physically-Based Modelling and Real-Time Simulation of Fluids.

NASA Astrophysics Data System (ADS)

Chen, Jim Xiong

1995-01-01

Simulating physically realistic complex fluid behaviors presents an extremely challenging problem for computer graphics researchers. Such behaviors include the effects of driving boats through water, blending differently colored fluids, rain falling and flowing on a terrain, fluids interacting in a Distributed Interactive Simulation (DIS), etc. Such capabilities are useful in computer art, advertising, education, entertainment, and training. We present a new method for physically-based modeling and real-time simulation of fluids in computer graphics and dynamic virtual environments. By solving the 2D Navier -Stokes equations using a CFD method, we map the surface into 3D using the corresponding pressures in the fluid flow field. This achieves realistic real-time fluid surface behaviors by employing the physical governing laws of fluids but avoiding extensive 3D fluid dynamics computations. To complement the surface behaviors, we calculate fluid volume and external boundary changes separately to achieve full 3D general fluid flow. To simulate physical activities in a DIS, we introduce a mechanism which uses a uniform time scale proportional to the clock-time and variable time-slicing to synchronize physical models such as fluids in the networked environment. Our approach can simulate many different fluid behaviors by changing the internal or external boundary conditions. It can model different kinds of fluids by varying the Reynolds number. It can simulate objects moving or floating in fluids. It can also produce synchronized general fluid flows in a DIS. Our model can serve as a testbed to simulate many other fluid phenomena which have never been successfully modeled previously.

Heterogeneously Assembled Metamaterials and Metadevices via 3D Modular Transfer Printing

NASA Astrophysics Data System (ADS)

Lee, Seungwoo; Kang, Byungsoo; Keum, Hohyun; Ahmed, Numair; Rogers, John A.; Ferreira, Placid M.; Kim, Seok; Min, Bumki

2016-06-01

Metamaterials have made the exotic control of the flow of electromagnetic waves possible, which is difficult to achieve with natural materials. In recent years, the emergence of functional metadevices has shown immense potential for the practical realization of highly efficient photonic devices. However, complex and heterogeneous architectures that enable diverse functionalities of metamaterials and metadevices have been challenging to realize because of the limited manufacturing capabilities of conventional fabrication methods. Here, we show that three-dimensional (3D) modular transfer printing can be used to construct diverse metamaterials in complex 3D architectures on universal substrates, which is attractive for achieving on-demand photonic properties. Few repetitive processing steps and rapid constructions are additional advantages of 3D modular transfer printing. Thus, this method provides a fascinating route to generate flexible and stretchable 2D/3D metamaterials and metadevices with heterogeneous material components, complex device architectures, and diverse functionalities.

Heterogeneously Assembled Metamaterials and Metadevices via 3D Modular Transfer Printing.

PubMed

Lee, Seungwoo; Kang, Byungsoo; Keum, Hohyun; Ahmed, Numair; Rogers, John A; Ferreira, Placid M; Kim, Seok; Min, Bumki

2016-06-10

Metamaterials have made the exotic control of the flow of electromagnetic waves possible, which is difficult to achieve with natural materials. In recent years, the emergence of functional metadevices has shown immense potential for the practical realization of highly efficient photonic devices. However, complex and heterogeneous architectures that enable diverse functionalities of metamaterials and metadevices have been challenging to realize because of the limited manufacturing capabilities of conventional fabrication methods. Here, we show that three-dimensional (3D) modular transfer printing can be used to construct diverse metamaterials in complex 3D architectures on universal substrates, which is attractive for achieving on-demand photonic properties. Few repetitive processing steps and rapid constructions are additional advantages of 3D modular transfer printing. Thus, this method provides a fascinating route to generate flexible and stretchable 2D/3D metamaterials and metadevices with heterogeneous material components, complex device architectures, and diverse functionalities.

Heterogeneously Assembled Metamaterials and Metadevices via 3D Modular Transfer Printing

PubMed Central

Lee, Seungwoo; Kang, Byungsoo; Keum, Hohyun; Ahmed, Numair; Rogers, John A.; Ferreira, Placid M.; Kim, Seok; Min, Bumki

2016-01-01

Metamaterials have made the exotic control of the flow of electromagnetic waves possible, which is difficult to achieve with natural materials. In recent years, the emergence of functional metadevices has shown immense potential for the practical realization of highly efficient photonic devices. However, complex and heterogeneous architectures that enable diverse functionalities of metamaterials and metadevices have been challenging to realize because of the limited manufacturing capabilities of conventional fabrication methods. Here, we show that three-dimensional (3D) modular transfer printing can be used to construct diverse metamaterials in complex 3D architectures on universal substrates, which is attractive for achieving on-demand photonic properties. Few repetitive processing steps and rapid constructions are additional advantages of 3D modular transfer printing. Thus, this method provides a fascinating route to generate flexible and stretchable 2D/3D metamaterials and metadevices with heterogeneous material components, complex device architectures, and diverse functionalities. PMID:27283594

Uranyl Ion Complexes with Long-Chain Aliphatic α,ω-Dicarboxylates and 3d-Block Metal Counterions.

PubMed

Thuéry, Pierre; Harrowfield, Jack

2016-03-07

Twelve new complexes were obtained from reaction of uranyl ions with the aliphatic dicarboxylic acids HOOC-(CH2)n-2-COOH (H2Cn; n = 7-10 and 12) under solvo-hydrothermal conditions, in the presence of 3d-block metal ions (Mn(2+), Fe(3+), Co(2+), Ni(2+), and Cu(2+)) and 2,2'-bipyridine (bipy) or 1,10-phenanthroline (phen). In contrast to previously reported triple-stranded helicates obtained with C9(2-) and C12(2-), all these complexes crystallize as polymeric one-dimensional (1D) or two-dimensional (2D) species. [Fe(bipy)3][(UO2)2(C7)3]·3H2O (1), [Cu(phen)2]2[(UO2)3(C7)4(H2O)2]·2H2O (2), and [Cu(bipy)2]2[(UO2)2(C9)3] (6), in which the 3d cation was reduced in situ, are 1D ladderlike polymers displaying tetra- or hexanuclear rings, of sufficient width to encompass two counterions in 2 and 6. The three complexes [Co(phen)3][(UO2)3(C8)3(O)]·H2O (3), [Ni(phen)3][(UO2)3(C8)3(O)]·H2O (4) and [Co(phen)3][(UO2)3(C9)3(O)]·H2O (5) contain bis(μ3-oxo)-bridged tetranuclear secondary building units, and they crystallize as deeply furrowed 2D assemblies. Depending on the nature of the counterion, C10(2-) gives [Ni(bipy)3][(UO2)2(C10)3]·2H2O (7), a 2D network displaying elongated decanuclear rings containing the counterions, or [Mn(phen)3][(UO2)2(C10)3]·6H2O (8), [Co(phen)3][(UO2)2(C10)3]·7H2O (9), and [Ni(phen)3][(UO2)2(C10)3]·7H2O (10), which consist of 2D assemblies with honeycomb topology; the hexanuclear rings in 8-10 are chairlike and occupied by one counterion and two uranyl groups from neighboring layers. Two complexes of the ligand with the longest chain, C12(2-), are reported. [UO2(C12)(bipy)] (11) is a neutral 1D species in which bipy chelates the uranyl ion and plays an important role in the packing through π-stacking interactions. Two polymeric units, 1D and 2D, coexist in the complex [Ni(bipy)3][(UO2)2(C12)3][UO2(C12)(H2O)2]·H2O (12); the 2D network has the honeycomb topology, but the hexanuclear rings are markedly convoluted, with local features akin to those in helicates, and the counterions are embedded in intralayer cavities. Emission spectra measured in the solid state show in most cases various degrees of quenching, with intense and well-resolved uranyl emission being observed only for complexes 2 and 11.

A comparison between coherent and noncoherent mobile systems in large Doppler shift, delay spread, and C/I environment

NASA Technical Reports Server (NTRS)

Feher, Kamilo

1993-01-01

The performance and implementation complexity of coherent and of noncoherent QPSK and GMSK modulation/demodulation techniques in a complex mobile satellite systems environment, including large Doppler shift, delay spread, and low C/I, are compared. We demonstrate that for large f(sub d)T(sub b) products, where f(sub d) is the Doppler shift and T(sub b) is the bit duration, noncoherent (discriminator detector or differential demodulation) systems have a lower BER floor than their coherent counterparts. For significant delay spreads, e.g., tau(sub rms) greater than 0.4 T(sub b), and low C/I, coherent systems outperform noncoherent systems. However, the synchronization time of coherent systems is longer than that of noncoherent systems. Spectral efficiency, overall capacity, and related hardware complexity issues of these systems are also analyzed. We demonstrate that coherent systems have a simpler overall architecture (IF filter implementation-cost versus carrier recovery) and are more robust in an RF frequency drift environment. Additionally, the prediction tools, computer simulations, and analysis of coherent systems is simpler. The threshold or capture effect in low C/I interference environment is critical for noncoherent discriminator based systems. We conclude with a comparison of hardware architectures of coherent and of noncoherent systems, including recent trends in commercial VLSI technology and direct baseband to RF transmit, RF to baseband (0-IF) receiver implementation strategies.

A comparison between coherent and noncoherent mobile systems in large Doppler shift, delay spread, and C/I environment

NASA Astrophysics Data System (ADS)

Feher, Kamilo

The performance and implementation complexity of coherent and of noncoherent QPSK and GMSK modulation/demodulation techniques in a complex mobile satellite systems environment, including large Doppler shift, delay spread, and low C/I, are compared. We demonstrate that for large f(sub d)T(sub b) products, where f(sub d) is the Doppler shift and T(sub b) is the bit duration, noncoherent (discriminator detector or differential demodulation) systems have a lower BER floor than their coherent counterparts. For significant delay spreads, e.g., tau(sub rms) greater than 0.4 T(sub b), and low C/I, coherent systems outperform noncoherent systems. However, the synchronization time of coherent systems is longer than that of noncoherent systems. Spectral efficiency, overall capacity, and related hardware complexity issues of these systems are also analyzed. We demonstrate that coherent systems have a simpler overall architecture (IF filter implementation-cost versus carrier recovery) and are more robust in an RF frequency drift environment. Additionally, the prediction tools, computer simulations, and analysis of coherent systems is simpler. The threshold or capture effect in low C/I interference environment is critical for noncoherent discriminator based systems. We conclude with a comparison of hardware architectures of coherent and of noncoherent systems, including recent trends in commercial VLSI technology and direct baseband to RF transmit, RF to baseband (0-IF) receiver implementation strategies.

A 3D Human Lung Tissue Model for Functional Studies on Mycobacterium tuberculosis Infection.

PubMed

Braian, Clara; Svensson, Mattias; Brighenti, Susanna; Lerm, Maria; Parasa, Venkata R

2015-10-05

Tuberculosis (TB) still holds a major threat to the health of people worldwide, and there is a need for cost-efficient but reliable models to help us understand the disease mechanisms and advance the discoveries of new treatment options. In vitro cell cultures of monolayers or co-cultures lack the three-dimensional (3D) environment and tissue responses. Herein, we describe an innovative in vitro model of a human lung tissue, which holds promise to be an effective tool for studying the complex events that occur during infection with Mycobacterium tuberculosis (M. tuberculosis). The 3D tissue model consists of tissue-specific epithelial cells and fibroblasts, which are cultured in a matrix of collagen on top of a porous membrane. Upon air exposure, the epithelial cells stratify and secrete mucus at the apical side. By introducing human primary macrophages infected with M. tuberculosis to the tissue model, we have shown that immune cells migrate into the infected-tissue and form early stages of TB granuloma. These structures recapitulate the distinct feature of human TB, the granuloma, which is fundamentally different or not commonly observed in widely used experimental animal models. This organotypic culture method enables the 3D visualization and robust quantitative analysis that provides pivotal information on spatial and temporal features of host cell-pathogen interactions. Taken together, the lung tissue model provides a physiologically relevant tissue micro-environment for studies on TB. Thus, the lung tissue model has potential implications for both basic mechanistic and applied studies. Importantly, the model allows addition or manipulation of individual cell types, which thereby widens its use for modelling a variety of infectious diseases that affect the lungs.

Automatic temperature computation for realistic IR simulation

NASA Astrophysics Data System (ADS)

Le Goff, Alain; Kersaudy, Philippe; Latger, Jean; Cathala, Thierry; Stolte, Nilo; Barillot, Philippe

2000-07-01

Polygon temperature computation in 3D virtual scenes is fundamental for IR image simulation. This article describes in detail the temperature calculation software and its current extensions, briefly presented in [1]. This software, called MURET, is used by the simulation workshop CHORALE of the French DGA. MURET is a one-dimensional thermal software, which accurately takes into account the material thermal attributes of three-dimensional scene and the variation of the environment characteristics (atmosphere) as a function of the time. Concerning the environment, absorbed incident fluxes are computed wavelength by wavelength, for each half an hour, druing 24 hours before the time of the simulation. For each polygon, incident fluxes are compsed of: direct solar fluxes, sky illumination (including diffuse solar fluxes). Concerning the materials, classical thermal attributes are associated to several layers, such as conductivity, absorption, spectral emissivity, density, specific heat, thickness and convection coefficients are taken into account. In the future, MURET will be able to simulate permeable natural materials (water influence) and vegetation natural materials (woods). This model of thermal attributes induces a very accurate polygon temperature computation for the complex 3D databases often found in CHORALE simulations. The kernel of MUET consists of an efficient ray tracer allowing to compute the history (over 24 hours) of the shadowed parts of the 3D scene and a library, responsible for the thermal computations. The great originality concerns the way the heating fluxes are computed. Using ray tracing, the flux received in each 3D point of the scene accurately takes into account the masking (hidden surfaces) between objects. By the way, this library supplies other thermal modules such as a thermal shows computation tool.

Robust model-based 3d/3D fusion using sparse matching for minimally invasive surgery.

PubMed

Neumann, Dominik; Grbic, Sasa; John, Matthias; Navab, Nassir; Hornegger, Joachim; Ionasec, Razvan

2013-01-01

Classical surgery is being disrupted by minimally invasive and transcatheter procedures. As there is no direct view or access to the affected anatomy, advanced imaging techniques such as 3D C-arm CT and C-arm fluoroscopy are routinely used for intra-operative guidance. However, intra-operative modalities have limited image quality of the soft tissue and a reliable assessment of the cardiac anatomy can only be made by injecting contrast agent, which is harmful to the patient and requires complex acquisition protocols. We propose a novel sparse matching approach for fusing high quality pre-operative CT and non-contrasted, non-gated intra-operative C-arm CT by utilizing robust machine learning and numerical optimization techniques. Thus, high-quality patient-specific models can be extracted from the pre-operative CT and mapped to the intra-operative imaging environment to guide minimally invasive procedures. Extensive quantitative experiments demonstrate that our model-based fusion approach has an average execution time of 2.9 s, while the accuracy lies within expert user confidence intervals.

Acentric 2-D ensembles of D-br-A electron-transfer chromophores via vectorial orientation within amphiphilic n-helix bundle peptides for photovoltaic device applications.

PubMed

Koo, Jaseung; Park, Jaehong; Tronin, Andrey; Zhang, Ruili; Krishnan, Venkata; Strzalka, Joseph; Kuzmenko, Ivan; Fry, H Christopher; Therien, Michael J; Blasie, J Kent

2012-02-14

We show that simply designed amphiphilic 4-helix bundle peptides can be utilized to vectorially orient a linearly extended donor-bridge-acceptor (D-br-A) electron transfer (ET) chromophore within its core. The bundle's interior is shown to provide a unique solvation environment for the D-br-A assembly not accessible in conventional solvents and thereby control the magnitudes of both light-induced ET and thermal charge recombination rate constants. The amphiphilicity of the bundle's exterior was employed to vectorially orient the peptide-chromophore complex at a liquid-gas interface, and its ends were tailored for subsequent covalent attachment to an inorganic surface, via a "directed assembly" approach. Structural data, combined with evaluation of the excited state dynamics exhibited by these peptide-chromophore complexes, demonstrate that densely packed, acentrically ordered 2-D monolayer ensembles of such complexes at high in-plane chromophore densities approaching 1/200 Å(2) offer unique potential as active layers in binary heterojunction photovoltaic devices.

RESEARCH AND DESIGN ABOUT VERSATILE 3D-CAD ENGINE FOR CONSTRUCTION

NASA Astrophysics Data System (ADS)

Tanaka, Shigenori; Kubota, Satoshi; Kitagawa, Etsuji; Monobe, Kantaro; Nakamura, Kenji

In the construction field of Japan, it is an important subject to build the environment where 3D-CAD data is used for CALS/EC, information construction, and an improvement in productivity. However, in the construction field, 3D-CAD software does not exist under the present circumstances. Then, in order to support development of domestic 3D-CAD software, it is required to develop a 3D-CAD engine. In this research, in order to familiarize the 3D-CAD software at low cost and quickly and build the environment where the 3D-CAD software is utilizable, investigation for designing a 3D-CAD engine is proposed. The target for investigation are the use scene of 3D-CAD, the seeds which accompany 3D-CAD, a standardization trend, existing products, IT component engineering. Based on results of the investigation, the functional requirements for the 3D-CAD engine for the construction field were concluded.

Coordination chemistry and catalytic activity of N-heterocyclic carbene iridium(I) complexes.

PubMed

Fu, Ching-Feng; Chang, Yung-Hung; Liu, Yi-Hong; Peng, Shei-Ming; Elsevier, Cornelis J; Chen, Jwu-Ting; Liu, Shiuh-Tzung

2009-09-21

Iridium complexes [(CO)2Ir(NHC-R)Cl] (R = Et-, 3a; PhCH2-, 3b; CH3OCH2CH2-, 3c; o-CH3OC6H4CH2-, 3d; NHC: N-heterocyclic carbene) are prepared via the carbene transfer from [(NHC-R)W(CO)5] to [Ir(COD)Cl]2. By using substitution with 13CO, we are able to estimate the activation energy (G) of the CO-exchange in 3a-d, which are in the range of 12-13 kcal mol-1, significantly higher than those for the phosphine analog [(CO)2Ir(PCy3)Cl]. Reactions of 3b and 3d with an equimolar amount of PPh3 result in the formation of the corresponding [(NHC-R)Ir(CO)(PPh3)Cl] with the phosphine and NHC in trans arrangement. In contrast, the analogous reaction of 3a or 3c with phosphine undergoes substitution followed by the anion metathesis to yield the corresponding di-substituted [(NHC-R)Ir(CO)(PPh3)2]BF4 (5) directly. Treatment of 3b or 3d with excess of PPh3 leads to the similar product of disubstitution 5b and 5d. The analysis for the IR data of carbonyliridium complexes provides the estimation of electron-donating power of NHCs versus phosphines. The NHC moiety on the iridium center cannot be replaced by phosphines, even 1,2-bis(diphenylphohino)ethane (dppe). All the carbene moieties on the iridium complexes are inert toward sulfur treatment, indicating a strong interaction between NHC and the iridium centers. Complexes 3a-c are active on the catalysis of the oxidative cyclization of 2-(o-aminophenyl)ethanol to yield the indole compound. The phosphine substituted complexes or analogs are less active.

The luminescence of nanoscale Y2Si2O7:Eu3+ materials.

PubMed

Lu, Shaozhe; Zhang, Jishen; Zhang, Jiahua

2010-03-01

The Y2Si2O7:Eu3+ sample was prepared with the sol-gel method. The Y2O3:EU3 was dispersed in SiO2, and the complex Y2Si2O7:Eu3+ particles were synthesized at high annealing temperature. The sample consisted of nearly spherical particles with an average size about 60 nm. The ultraviolet excitation spectra and emission spectra were measured. The sample excited by short ultraviolet light showed strongly red luminescence and fine monochromaticity. The luminescence was strongest from the 5D0 --> 7F2 electric dipole transition located at 611 nm. The excitation spectra of Y2Si2O7:Eu3+ excited with ultraviolet lights showed that the peak of the Eu(3+)-O2- charge transition band located at about 240 nm. During monitoring of different emission peaks of 5D0 --> 7F2, the charge transition band in the excitation spectra shifted, and the relative intensity of emission spectra changed obviously under the excitation of different ultraviolet wavelengths. These results confirmed that the Eu3+ could be excited with ultraviolet radiation of different wavelengths. At low temperature, using Eu3+ ions as fluorescence probes, we monitored the emission peaks of 5D0 --> 7F1 and 5D0 --> 7F2 transitions and measured the excitation spectra of 7F0 --> 5D0, 5D0 --> 7F1, and 5D0 --> 7F2 site-selective excitation spectra. These results indicated that Eu3+ ions are located in different local environments in the Y2Si2O7 host.

Industrial metrology as applied to large physics experiments

DOE Office of Scientific and Technical Information (OSTI.GOV)

Veal, D.

1993-05-01

A physics experiment is a large complex 3-D object (typ. 1200 m{sup 3}, 35000 tonnes), with sub-millimetric alignment requirements. Two generic survey alignment tasks can be identified; first, an iterative positioning of the apparatus subsystems in space and, second, a quantification of as-built parameters. The most convenient measurement technique is industrial triangulation but the complexity of the measured object and measurement environment constraints frequently requires a more sophisticated approach. To enlarge the ``survey alignment toolbox`` measurement techniques commonly associated with other disciplines such as geodesy, applied geodesy for accelerator alignment, and mechanical engineering are also used. Disparate observables require amore » heavy reliance on least squares programs for campaign pre-analysis and calculation. This paper will offer an introduction to the alignment of physics experiments and will identify trends for the next generation of SSC experiments.« less

Dual-Color Click Beetle Luciferase Heteroprotein Fragment Complementation Assays

PubMed Central

Villalobos, Victor; Naik, Snehal; Bruinsma, Monique; Dothager, Robin S.; Pan, Mei-Hsiu; Samrakandi, Mustapha; Moss, Britney; Elhammali, Adnan; Piwnica-Worms, David

2010-01-01

Summary Understanding the functional complexity of protein interactions requires mapping biomolecular complexes within the cellular environment over biologically-relevant time scales. Herein we describe a novel set of reversible, multicolored heteroprotein complementation fragments based on various firefly and click beetle luciferases that utilize the same substrate, D-luciferin. Luciferase heteroprotein fragment complementation systems enabled dual-color quantification of two discreet pairs of interacting proteins simultaneously or two distinct proteins interacting with a third shared protein in live cells. Using real-time analysis of click beetle green and click beetle red luciferase heteroprotein fragment complementation applied to β-TrCP, an E3-ligase common to the regulation of both β-catenin and IκBα, GSK3β was identified as a novel candidate kinase regulating IκBα processing. These dual-color protein interaction switches may enable directed dynamic analysis of a variety of protein interactions in living cells. PMID:20851351

Prototyping a Sensor Enabled 3d Citymodel on Geospatial Managed Objects

NASA Astrophysics Data System (ADS)

Kjems, E.; Kolář, J.

2013-09-01

One of the major development efforts within the GI Science domain are pointing at sensor based information and the usage of real time information coming from geographic referenced features in general. At the same time 3D City models are mostly justified as being objects for visualization purposes rather than constituting the foundation of a geographic data representation of the world. The combination of 3D city models and real time information based systems though can provide a whole new setup for data fusion within an urban environment and provide time critical information preserving our limited resources in the most sustainable way. Using 3D models with consistent object definitions give us the possibility to avoid troublesome abstractions of reality, and design even complex urban systems fusing information from various sources of data. These systems are difficult to design with the traditional software development approach based on major software packages and traditional data exchange. The data stream is varying from urban domain to urban domain and from system to system why it is almost impossible to design a complete system taking care of all thinkable instances now and in the future within one constraint software design complex. On several occasions we have been advocating for a new end advanced formulation of real world features using the concept of Geospatial Managed Objects (GMO). This paper presents the outcome of the InfraWorld project, a 4 million Euro project financed primarily by the Norwegian Research Council where the concept of GMO's have been applied in various situations on various running platforms of an urban system. The paper will be focusing on user experiences and interfaces rather then core technical and developmental issues. The project was primarily focusing on prototyping rather than realistic implementations although the results concerning applicability are quite clear.

Making Web3D Less Scary: Toward Easy-to-Use Web3D e-Learning Content Development Tools for Educators

ERIC Educational Resources Information Center

de Byl, Penny

2009-01-01

Penny de Byl argues that one of the biggest challenges facing educators today is the integration of rich and immersive three-dimensional environments with existing teaching and learning materials. To empower educators with the ability to embrace emerging Web3D technologies, the Advanced Learning and Immersive Virtual Environment (ALIVE) research…

Magnetically tunable 1D Coulomb drag: Theory

NASA Astrophysics Data System (ADS)

Tylan-Tyler, Anthony; Tang, Yuhe; Levy, Jeremy

In this work, we examine the Coulomb drag effect in 1D nanowires in close proximity, focusing on experimental parameters relevant to complex-oxide nanostructures. Previous work on this problem examined Coulomb drag through quantum point contacts, where effective capacitive coupling between the 2D leads of the system generates the drag voltage. In our case, the entire system is composed of 1D components and thus a more careful treatment of the Coulomb interactions is required. This more complex environment then leads to the ability to switch the drag voltage by an applied magnetic field without altering the current supplied to the drive system. We gratefully acknowledge financial support from ONR N00014-15-1-2847 and DOE DE-SC0014417.

Development of a Remote Accessibility Assessment System through three-dimensional reconstruction technology.

PubMed

Kim, Jong Bae; Brienza, David M

2006-01-01

A Remote Accessibility Assessment System (RAAS) that uses three-dimensional (3-D) reconstruction technology is being developed; it enables clinicians to assess the wheelchair accessibility of users' built environments from a remote location. The RAAS uses commercial software to construct 3-D virtualized environments from photographs. We developed custom screening algorithms and instruments for analyzing accessibility. Characteristics of the camera and 3-D reconstruction software chosen for the system significantly affect its overall reliability. In this study, we performed an accuracy assessment to verify that commercial hardware and software can construct accurate 3-D models by analyzing the accuracy of dimensional measurements in a virtual environment and a comparison of dimensional measurements from 3-D models created with four cameras/settings. Based on these two analyses, we were able to specify a consumer-grade digital camera and PhotoModeler (EOS Systems, Inc, Vancouver, Canada) software for this system. Finally, we performed a feasibility analysis of the system in an actual environment to evaluate its ability to assess the accessibility of a wheelchair user's typical built environment. The field test resulted in an accurate accessibility assessment and thus validated our system.

Using Virtual Reality For Outreach Purposes in Planetology

NASA Astrophysics Data System (ADS)

Civet, François; Le Mouélic, Stéphane; Le Menn, Erwan; Beaunay, Stéphanie

2016-10-01

2016 has been a year marked by a technological breakthrough : the availability for the first time to the general public of technologically mature virtual reality devices. Virtual Reality consists in visually immerging a user in a 3D environment reproduced either from real and/or imaginary data, with the possibility to move and eventually interact with the different elements. In planetology, most of the places will remain inaccessible to the public for a while, but a fleet of dedicated spacecraft's such as orbiters, landers and rovers allow the possibility to virtually reconstruct the environments, using image processing, cartography and photogrammetry. Virtual reality can then bridge the gap to virtually "send" any user into the place and enjoy the exploration.We are investigating several type of devices to render orbital or ground based data of planetological interest, mostly from Mars. The most simple system consists of a "cardboard" headset, on which the user can simply use his cellphone as the screen. A more comfortable experience is obtained with more complex systems such as the HTC vive or Oculus Rift headsets, which include a tracking system important to minimize motion sickness. The third environment that we have developed is based on the CAVE concept, were four 3D video projectors are used to project on three 2x3m walls plus the ground. These systems can be used for scientific data analysis, but also prove to be perfectly suited for outreach and education purposes.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, Zhi-Hao; Zhao, Yue; Chen, Shui-Sheng

Seven new coordination polymers [Zn(H{sub 2}L)(mbdc)] (1), [Zn(H{sub 3}L)(btc)] (2), [Zn(H{sub 2}L)(Hbtc)] (3), [Zn(H{sub 2}L)(Hbtc)]·H{sub 2}O (4), [Zn{sub 2}(H{sub 2}L)(btc)(μ{sub 2}-OH)] (5), [Cd(H{sub 2}L)(mbdc)] (6) and [Cd{sub 3}(H{sub 2}L){sub 2}(btc){sub 2}(H{sub 2}O)]·5H{sub 2}O (7) were synthesized by reactions of the corresponding metal salt with rigid ligand 1,3-di(1H-imidazol-4-yl)benzene (H{sub 2}L) and different carboxylic acids of 1,3-benzenedicarboxylic acid (H{sub 2}mbdc) and benzene-1,3,5-tricarboxylic acid (H{sub 3}btc), respectively. The results of X-ray crystallographic analysis indicate that complex 1 is 1D chain while 2 is a (3,3)-connected 2D network with Point (Schläfli) symbol of (4,8{sup 2}). Complexes 3 and 6 are 2D networks, 4 ismore » a 3-fold interpenetrating 3D framework with Point (Schläfli) symbol of (6{sup 5},8) and 5 is a (3,8)-connected 2D network with Point (Schläfli) symbol of (3,4{sup 2}){sub 2}(3{sup 4},4{sup 6},5{sup 6},6{sup 8},7{sup 3},8), while 7 is a (3,10)-connected 3D net with Schläfli symbol of (3,4,5){sub 2}(3{sup 4},4{sup 8},5{sup 18},6{sup 12},7{sup 2},8). The thermal stability and photoluminescence of the complexes were investigated. Furthermore, DFT calculations were performed for 2–4 to discuss the temperature controlled self-assembly of the complexes. - Graphical abstract: Seven new coordination polymers with multicarboxylate and rigid ditopic 4-imidazole containing ligands have been obtained and found to show different structures and topologies. - Highlights: • Metal complexes with diverse structures of 1D chain, 2D network and 3D framework. • Mixed ligands of 1,3-di(1H-imidazol-4-yl)benzene and multicarboxylate. • Photoluminescence property.« less

3D Printer-Manufacturing of Complex Geometry Elements

NASA Astrophysics Data System (ADS)

Ciubară, A.; Burlea, Ș L.; Axinte, M.; Cimpoeșu, R.; Chicet, D. L.; Manole, V.; Burlea, G.; Cimpoeșu, N.

2018-06-01

In the last 5-10 years the process of 3D printing has an incredible advanced in all the fields with a tremendous number of applications. Plastic materials exhibit highly beneficial mechanical properties while delivering complex designs impossible to achieve using conventional manufacturing. In this article the printing process (filling degree, time, complications and details finesse) of few plastic elements with complicated geometry and fine details was analyzed and comment. 3D printing offers many of the thermoplastics and industrial materials found in conventional manufacturing. The advantages and disadvantages of 3D printing for plastic parts are discussed. Time of production for an element with complex geometry, from the design to final cut, was evaluated.

Adaptive computational methods for aerothermal heating analysis

NASA Technical Reports Server (NTRS)

Price, John M.; Oden, J. Tinsley

1988-01-01

The development of adaptive gridding techniques for finite-element analysis of fluid dynamics equations is described. The developmental work was done with the Euler equations with concentration on shock and inviscid flow field capturing. Ultimately this methodology is to be applied to a viscous analysis for the purpose of predicting accurate aerothermal loads on complex shapes subjected to high speed flow environments. The development of local error estimate strategies as a basis for refinement strategies is discussed, as well as the refinement strategies themselves. The application of the strategies to triangular elements and a finite-element flux-corrected-transport numerical scheme are presented. The implementation of these strategies in the GIM/PAGE code for 2-D and 3-D applications is documented and demonstrated.

HVS: an image-based approach for constructing virtual environments

NASA Astrophysics Data System (ADS)

Zhang, Maojun; Zhong, Li; Sun, Lifeng; Li, Yunhao

1998-09-01

Virtual Reality Systems can construct virtual environment which provide an interactive walkthrough experience. Traditionally, walkthrough is performed by modeling and rendering 3D computer graphics in real-time. Despite the rapid advance of computer graphics technique, the rendering engine usually places a limit on scene complexity and rendering quality. This paper presents a approach which uses the real-world image or synthesized image to comprise a virtual environment. The real-world image or synthesized image can be recorded by camera, or synthesized by off-line multispectral image processing for Landsat TM (Thematic Mapper) Imagery and SPOT HRV imagery. They are digitally warped on-the-fly to simulate walking forward/backward, to left/right and 360-degree watching around. We have developed a system HVS (Hyper Video System) based on these principles. HVS improves upon QuickTime VR and Surround Video in the walking forward/backward.

Multiresolutional schemata for unsupervised learning of autonomous robots for 3D space operation

NASA Technical Reports Server (NTRS)

Lacaze, Alberto; Meystel, Michael; Meystel, Alex

1994-01-01

This paper describes a novel approach to the development of a learning control system for autonomous space robot (ASR) which presents the ASR as a 'baby' -- that is, a system with no a priori knowledge of the world in which it operates, but with behavior acquisition techniques that allows it to build this knowledge from the experiences of actions within a particular environment (we will call it an Astro-baby). The learning techniques are rooted in the recursive algorithm for inductive generation of nested schemata molded from processes of early cognitive development in humans. The algorithm extracts data from the environment and by means of correlation and abduction, it creates schemata that are used for control. This system is robust enough to deal with a constantly changing environment because such changes provoke the creation of new schemata by generalizing from experiences, while still maintaining minimal computational complexity, thanks to the system's multiresolutional nature.

Understanding the Electronic Structure of 4d Metal Complexes: From Molecular Spinors to L-Edge Spectra of a di-Ru Catalyst

DOE Office of Scientific and Technical Information (OSTI.GOV)

Alperovich, Igor; Smolentsev, Grigory; Moonshiram, Dooshaye

2015-09-17

L{sub 2,3}-edge X-ray absorption spectroscopy (XAS) has demonstrated unique capabilities for the analysis of the electronic structure of di-Ru complexes such as the blue dimer cis,cis-[Ru{sub 2}{sup III}O(H{sub 2}O){sub 2}(bpy){sub 4}]{sup 4+} water oxidation catalyst. Spectra of the blue dimer and the monomeric [Ru(NH{sub 3}){sub 6}]{sup 3+} model complex show considerably different splitting of the Ru L{sub 2,3} absorption edge, which reflects changes in the relative energies of the Ru 4d orbitals caused by hybridization with a bridging ligand and spin-orbit coupling effects. To aid the interpretation of spectroscopic data, we developed a new approach, which computes L{sub 2,3}-edges XASmore » spectra as dipole transitions between molecular spinors of 4d transition metal complexes. This allows for careful inclusion of the spin-orbit coupling effects and the hybridization of the Ru 4d and ligand orbitals. The obtained theoretical Ru L{sub 2,3}-edge spectra are in close agreement with experiment. Critically, existing single-electron methods (FEFF, FDMNES) broadly used to simulate XAS could not reproduce the experimental Ru L-edge spectra for the [Ru(NH{sub 3}){sub 6}]{sup 3+} model complex nor for the blue dimer, while charge transfer multiplet (CTM) calculations were not applicable due to the complexity and low symmetry of the blue dimer water oxidation catalyst. We demonstrated that L-edge spectroscopy is informative for analysis of bridging metal complexes. The developed computational approach enhances L-edge spectroscopy as a tool for analysis of the electronic structures of complexes, materials, catalysts, and reactive intermediates with 4d transition metals.« less

Aminopyridine derivatives controlled the assembly and various properties of Cu-BTC metal-organic frameworks.

PubMed

Wang, Xiuli; Le, Mao; Lin, Hongyan; Luan, Jian; Liu, Guocheng; Liu, Danna

2015-08-21

Three Cu(ii) metal-organic frameworks (MOFs) based on 1,3,5-benzenetricarboxylic acid (H3BTC) and three aminopyridine derivatives with different lengths and coordination groups, namely [Cu2(3-azpy)(HBTC)(H2BTC)(μ3-OH)(H2O)2] (), [Cu2(3-ppca)(BTC)(H2O)3]·H2O (), [Cu2(3-ebpba)(BTC)(μ3-OH)] () [3-azpy = 3,3'-azopyridine, 3-ppca = N-(pyridin-3-yl)pyrazine-2-carboxamide, 3-ebpba = (E)-4,4'-(ethene-1,2-diyl)bis(N-pyridin-3-yl)benzamide)], have been hydrothermally synthesized and structurally characterized by elemental analyses, IR, PXRD, TG and single crystal X-ray diffraction analyses. The title MOFs display versatile structural features with 2D and 3D frameworks. Complex exhibits a 2D layer, which is constructed from the 3-azpy bridging ligands and a 1D ladder-like Cu-BTC chain with tetranuclear copper clusters. The 3-azpy was in situ transformed from 3-aminopyridine under the hydrothermal conditions. Complex shows a rare 3D framework, which features a (3,3,3,3)-connected topology with a Schläfli symbol of {8·10·12}2{8(2)·10}2. Complex exhibits a (3,8)-connected {4·6(2)}2{4(2)·6(22)·7·8(3)} topology based on tetranuclear copper clusters. The influence of aminopyridine-based ligands on the structures and properties of the title complexes has been discussed. The electrocatalytic and photocatalytic properties of complexes have also been investigated in detail.

3D Printing of Conductive Complex Structures with In Situ Generation of Silver Nanoparticles.

PubMed

Fantino, Erika; Chiappone, Annalisa; Roppolo, Ignazio; Manfredi, Diego; Bongiovanni, Roberta; Pirri, Candido Fabrizio; Calignano, Flaviana

2016-05-01

Coupling the photoreduction of a metal precursor with 3D-printing technology is shown to allow the fabrication of conductive 3D hybrid structures consisting of metal nanoparticles and organic polymers shaped in complex multilayered architectures. 3D conductive structures are fabricated incorporating silver nitrate into a photocurable oligomer in the presence of suitable photoinitiators and exposing them to a digital light system. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The Physics and Applications of a 3D Plasmonic Nanostructure

NASA Astrophysics Data System (ADS)

Terranova, Brandon B.

In this work, the dynamics of electromagnetic field interactions with free electrons in a 3D metallic nanostructure is evaluated theoretically. This dissertation starts by reviewing the relevant fundamentals of plasmonics and modern applications of plasmonic systems. Then, motivated by the need to have a simpler way of understanding the surface charge dynamics on complex plasmonic nanostructures, a new plasmon hybridization tree method is introduced. This method provides the plasmonicist with an intuitive way to determine the response of free electrons to incident light in complex nanostructures within the electrostatic regime. Next, a novel 3D plasmonic nanostructure utilizing reflective plasmonic coupling is designed to perform biosensing and plasmonic tweezing applications. By applying analytical and numerical methods, the effectiveness of this nanostructure at performing these applications is determined from the plasmonic response of the nanostructure to an excitation beam of coherent light. During this analysis, it was discovered that under certain conditions, this 3D nanostructure exhibits a plasmonic Fano resonance resulting from the interference of an in-plane dark mode and an out-of-plane bright mode. In evaluating this nanostructure for sensing changes in the local dielectric environment, a figure of merit of 68 is calculated, which is competitive with current localized surface plasmon resonance refractometric sensors. By evaluating the Maxwell stress tensor on a test particle in the vicinity of the nanostructure, it was found that under the right conditions, this plasmonic nanostructure design is capable of imparting forces greater than 10.5 nN on dielectric objects of nanoscale dimensions. The results obtained in these studies provides new routes to the design and engineering of 3D plasmonic nanostructures and Fano resonances in these systems. In addition, the nanostructure presented in this work and the design principles it utilizes have shown performance metrics which make it an important contribution to the fields of LSPR biosensing and plasmonic trapping and force transduction.

Full Immersive Virtual Environment Cave[TM] in Chemistry Education

ERIC Educational Resources Information Center

Limniou, M.; Roberts, D.; Papadopoulos, N.

2008-01-01

By comparing two-dimensional (2D) chemical animations designed for computer's desktop with three-dimensional (3D) chemical animations designed for the full immersive virtual reality environment CAVE[TM] we studied how virtual reality environments could raise student's interest and motivation for learning. By using the 3ds max[TM], we can visualize…

Adaptive 3D Virtual Learning Environments--A Review of the Literature

ERIC Educational Resources Information Center

Scott, Ezequiel; Soria, Alvaro; Campo, Marcelo

2017-01-01

New ways of learning have emerged in the last years by using computers in education. For instance, many Virtual Learning Environments have been widely adopted by educators, obtaining promising outcomes. Recently, these environments have evolved into more advanced ones using 3D technologies and taking into account the individual learner needs and…

A Literature Review on Operator Interface Technologies for Network Enabled Operational Environments Using Complex System Analysis

DTIC Science & Technology

2009-05-30

d’interface fondées sur le comportement et sur la psychologie , ainsi que des méthodes de conception et de mise en œuvre d’interfaces multi-agents. On a mis...réseaucentriques. Ces technologies comprennent des approches de conception d’interface fondées sur le comportement et sur la psychologie , ainsi que des

3D Planetary Data Visualization with CesiumJS

NASA Astrophysics Data System (ADS)

Larsen, K. W.; DeWolfe, A. W.; Nguyen, D.; Sanchez, F.; Lindholm, D. M.

2017-12-01

Complex spacecraft orbits and multi-instrument observations can be challenging to visualize with traditional 2D plots. To facilitate the exploration of planetary science data, we have developed a set of web-based interactive 3D visualizations for the MAVEN and MMS missions using the free CesiumJS library. The Mars Atmospheric and Volatile Evolution (MAVEN) mission has been collecting data at Mars since September 2014. The MAVEN3D project allows playback of one day's orbit at a time, displaying the spacecraft's position and orientation. Selected science data sets can be overplotted on the orbit track, including vectors for magnetic field and ion flow velocities. We also provide an overlay the M-GITM model on the planet itself. MAVEN3D is available at the MAVEN public website at: https://lasp.colorado.edu/maven/sdc/public/pages/maven3d/ The Magnetospheric MultiScale Mission (MMS) consists of one hundred instruments on four spacecraft flying in formation around Earth, investigating the interactions between the solar wind and Earth's magnetic field. While the highest temporal resolution data isn't received and processed until later, continuous daily observations of the particle and field environments are made available as soon as they are received. Traditional `quick-look' static plots have long been the first interaction with data from a mission of this nature. Our new 3D Quicklook viewer allows data from all four spacecraft to be viewed in an interactive web application as soon as the data is ingested into the MMS Science Data Center, less than one day after collection, in order to better help identify scientifically interesting data.

Grasping trajectories in a virtual environment adhere to Weber's law.

PubMed

Ozana, Aviad; Berman, Sigal; Ganel, Tzvi

2018-06-01

Virtual-reality and telerobotic devices simulate local motor control of virtual objects within computerized environments. Here, we explored grasping kinematics within a virtual environment and tested whether, as in normal 3D grasping, trajectories in the virtual environment are performed analytically, violating Weber's law with respect to object's size. Participants were asked to grasp a series of 2D objects using a haptic system, which projected their movements to a virtual space presented on a computer screen. The apparatus also provided object-specific haptic information upon "touching" the edges of the virtual targets. The results showed that grasping movements performed within the virtual environment did not produce the typical analytical trajectory pattern obtained during 3D grasping. Unlike as in 3D grasping, grasping trajectories in the virtual environment adhered to Weber's law, which indicates relative resolution in size processing. In addition, the trajectory patterns differed from typical trajectories obtained during 3D grasping, with longer times to complete the movement, and with maximum grip apertures appearing relatively early in the movement. The results suggest that grasping movements within a virtual environment could differ from those performed in real space, and are subjected to irrelevant effects of perceptual information. Such atypical pattern of visuomotor control may be mediated by the lack of complete transparency between the interface and the virtual environment in terms of the provided visual and haptic feedback. Possible implications of the findings to movement control within robotic and virtual environments are further discussed.

3D Bioprinting for Engineering Complex Tissues

PubMed Central

Mandrycky, Christian; Wang, Zongjie; Kim, Keekyoung; Kim, Deok-Ho

2016-01-01

Bioprinting is a 3D fabrication technology used to precisely dispense cell-laden biomaterials for the construction of complex 3D functional living tissues or artificial organs. While still in its early stages, bioprinting strategies have demonstrated their potential use in regenerative medicine to generate a variety of transplantable tissues, including skin, cartilage, and bone. However, current bioprinting approaches still have technical challenges in terms of high-resolution cell deposition, controlled cell distributions, vascularization, and innervation within complex 3D tissues. While no one-size-fits-all approach to bioprinting has emerged, it remains an on-demand, versatile fabrication technique that may address the growing organ shortage as well as provide a high-throughput method for cell patterning at the micrometer scale for broad biomedical engineering applications. In this review, we introduce the basic principles, materials, integration strategies and applications of bioprinting. We also discuss the recent developments, current challenges and future prospects of 3D bioprinting for engineering complex tissues. Combined with recent advances in human pluripotent stem cell technologies, 3D-bioprinted tissue models could serve as an enabling platform for high-throughput predictive drug screening and more effective regenerative therapies. PMID:26724184

3D bioprinting for engineering complex tissues.

PubMed

Mandrycky, Christian; Wang, Zongjie; Kim, Keekyoung; Kim, Deok-Ho

2016-01-01

Bioprinting is a 3D fabrication technology used to precisely dispense cell-laden biomaterials for the construction of complex 3D functional living tissues or artificial organs. While still in its early stages, bioprinting strategies have demonstrated their potential use in regenerative medicine to generate a variety of transplantable tissues, including skin, cartilage, and bone. However, current bioprinting approaches still have technical challenges in terms of high-resolution cell deposition, controlled cell distributions, vascularization, and innervation within complex 3D tissues. While no one-size-fits-all approach to bioprinting has emerged, it remains an on-demand, versatile fabrication technique that may address the growing organ shortage as well as provide a high-throughput method for cell patterning at the micrometer scale for broad biomedical engineering applications. In this review, we introduce the basic principles, materials, integration strategies and applications of bioprinting. We also discuss the recent developments, current challenges and future prospects of 3D bioprinting for engineering complex tissues. Combined with recent advances in human pluripotent stem cell technologies, 3D-bioprinted tissue models could serve as an enabling platform for high-throughput predictive drug screening and more effective regenerative therapies. Copyright © 2015 Elsevier Inc. All rights reserved.

Protocols and characterization data for 2D, 3D, and slice-based tumor models from the PREDECT project.

PubMed

de Hoogt, Ronald; Estrada, Marta F; Vidic, Suzana; Davies, Emma J; Osswald, Annika; Barbier, Michael; Santo, Vítor E; Gjerde, Kjersti; van Zoggel, Hanneke J A A; Blom, Sami; Dong, Meng; Närhi, Katja; Boghaert, Erwin; Brito, Catarina; Chong, Yolanda; Sommergruber, Wolfgang; van der Kuip, Heiko; van Weerden, Wytske M; Verschuren, Emmy W; Hickman, John; Graeser, Ralph

2017-11-21

Two-dimensional (2D) culture of cancer cells in vitro does not recapitulate the three-dimensional (3D) architecture, heterogeneity and complexity of human tumors. More representative models are required that better reflect key aspects of tumor biology. These are essential studies of cancer biology and immunology as well as for target validation and drug discovery. The Innovative Medicines Initiative (IMI) consortium PREDECT (www.predect.eu) characterized in vitro models of three solid tumor types with the goal to capture elements of tumor complexity and heterogeneity. 2D culture and 3D mono- and stromal co-cultures of increasing complexity, and precision-cut tumor slice models were established. Robust protocols for the generation of these platforms are described. Tissue microarrays were prepared from all the models, permitting immunohistochemical analysis of individual cells, capturing heterogeneity. 3D cultures were also characterized using image analysis. Detailed step-by-step protocols, exemplary datasets from the 2D, 3D, and slice models, and refined analytical methods were established and are presented.

Protocols and characterization data for 2D, 3D, and slice-based tumor models from the PREDECT project

PubMed Central

de Hoogt, Ronald; Estrada, Marta F.; Vidic, Suzana; Davies, Emma J.; Osswald, Annika; Barbier, Michael; Santo, Vítor E.; Gjerde, Kjersti; van Zoggel, Hanneke J. A. A.; Blom, Sami; Dong, Meng; Närhi, Katja; Boghaert, Erwin; Brito, Catarina; Chong, Yolanda; Sommergruber, Wolfgang; van der Kuip, Heiko; van Weerden, Wytske M.; Verschuren, Emmy W.; Hickman, John; Graeser, Ralph

2017-01-01

Two-dimensional (2D) culture of cancer cells in vitro does not recapitulate the three-dimensional (3D) architecture, heterogeneity and complexity of human tumors. More representative models are required that better reflect key aspects of tumor biology. These are essential studies of cancer biology and immunology as well as for target validation and drug discovery. The Innovative Medicines Initiative (IMI) consortium PREDECT (www.predect.eu) characterized in vitro models of three solid tumor types with the goal to capture elements of tumor complexity and heterogeneity. 2D culture and 3D mono- and stromal co-cultures of increasing complexity, and precision-cut tumor slice models were established. Robust protocols for the generation of these platforms are described. Tissue microarrays were prepared from all the models, permitting immunohistochemical analysis of individual cells, capturing heterogeneity. 3D cultures were also characterized using image analysis. Detailed step-by-step protocols, exemplary datasets from the 2D, 3D, and slice models, and refined analytical methods were established and are presented. PMID:29160867

CarD stabilizes mycobacterial open complexes via a two-tiered kinetic mechanism

PubMed Central

Rammohan, Jayan; Ruiz Manzano, Ana; Garner, Ashley L.; Stallings, Christina L.; Galburt, Eric A.

2015-01-01

CarD is an essential and global transcriptional regulator in mycobacteria. While its biological role is unclear, CarD functions by interacting directly with RNA polymerase (RNAP) holoenzyme promoter complexes. Here, using a fluorescent reporter of open complex, we quantitate RPo formation in real time and show that Mycobacterium tuberculosis CarD has a dramatic effect on the energetics of RNAP bound complexes on the M. tuberculosis rrnAP3 ribosomal RNA promoter. The data reveal that Mycobacterium bovis RNAP exhibits an unstable RPo that is stabilized by CarD and suggest that CarD uses a two-tiered, concentration-dependent mechanism by associating with open and closed complexes with different affinities. Specifically, the kinetics of open-complex formation can be explained by a model where, at saturating concentrations of CarD, the rate of bubble collapse is slowed and the rate of opening is accelerated. The kinetics and open-complex stabilities of CarD mutants further clarify the roles played by the key residues W85, K90 and R25 previously shown to affect CarD-dependent gene regulation in vivo. In contrast to M. bovis RNAP, Escherichia coli RNAP efficiently forms RPo on rrnAP3, suggesting an important difference between the polymerases themselves and highlighting how transcriptional machinery can vary across bacterial genera. PMID:25697505

Development and characterization of a 3D multicell microtissue culture model of airway smooth muscle.

PubMed

West, Adrian R; Zaman, Nishat; Cole, Darren J; Walker, Matthew J; Legant, Wesley R; Boudou, Thomas; Chen, Christopher S; Favreau, John T; Gaudette, Glenn R; Cowley, Elizabeth A; Maksym, Geoffrey N

2013-01-01

Airway smooth muscle (ASM) cellular and molecular biology is typically studied with single-cell cultures grown on flat 2D substrates. However, cells in vivo exist as part of complex 3D structures, and it is well established in other cell types that altering substrate geometry exerts potent effects on phenotype and function. These factors may be especially relevant to asthma, a disease characterized by structural remodeling of the airway wall, and highlights a need for more physiologically relevant models of ASM function. We utilized a tissue engineering platform known as microfabricated tissue gauges to develop a 3D culture model of ASM featuring arrays of ∼0.4 mm long, ∼350 cell "microtissues" capable of simultaneous contractile force measurement and cell-level microscopy. ASM-only microtissues generated baseline tension, exhibited strong cellular organization, and developed actin stress fibers, but lost structural integrity and dissociated from the cantilevers within 3 days. Addition of 3T3-fibroblasts dramatically improved survival times without affecting tension development or morphology. ASM-3T3 microtissues contracted similarly to ex vivo ASM, exhibiting reproducible responses to a range of contractile and relaxant agents. Compared with 2D cultures, microtissues demonstrated identical responses to acetylcholine and KCl, but not histamine, forskolin, or cytochalasin D, suggesting that contractility is regulated by substrate geometry. Microtissues represent a novel model for studying ASM, incorporating a physiological 3D structure, realistic mechanical environment, coculture of multiple cells types, and comparable contractile properties to existing models. This new model allows for rapid screening of biochemical and mechanical factors to provide insight into ASM dysfunction in asthma.

Microfluidic engineered high cell density three-dimensional neural cultures

NASA Astrophysics Data System (ADS)

Cullen, D. Kacy; Vukasinovic, Jelena; Glezer, Ari; La Placa, Michelle C.

2007-06-01

Three-dimensional (3D) neural cultures with cells distributed throughout a thick, bioactive protein scaffold may better represent neurobiological phenomena than planar correlates lacking matrix support. Neural cells in vivo interact within a complex, multicellular environment with tightly coupled 3D cell-cell/cell-matrix interactions; however, thick 3D neural cultures at cell densities approaching that of brain rapidly decay, presumably due to diffusion limited interstitial mass transport. To address this issue, we have developed a novel perfusion platform that utilizes forced intercellular convection to enhance mass transport. First, we demonstrated that in thick (>500 µm) 3D neural cultures supported by passive diffusion, cell densities <=5.0 × 103 cells mm-3 were required for survival. In 3D neuronal and neuronal-astrocytic co-cultures with increased cell density (>=104 cells mm-3), continuous medium perfusion at 2.0-11.0 µL min-1 improved viability compared to non-perfused cultures (p < 0.01), which exhibited widespread cell death and matrix degradation. In perfused cultures, survival was dependent on proximity to the perfusion source at 2.00-6.25 µL min-1 (p < 0.05); however, at perfusion rates of 10.0-11.0 µL min-1 survival did not depend on the distance from the perfusion source, and resulted in a preservation of cell density with >90% viability in both neuronal cultures and neuronal-astrocytic co-cultures. This work demonstrates the utility of forced interstitial convection in improving the survival of high cell density 3D engineered neural constructs and may aid in the development of novel tissue-engineered systems reconstituting 3D cell-cell/cell-matrix interactions.

Phenotypic Characterization of Toxic Compound Effects on Liver Spheroids Derived from iPSC Using Confocal Imaging and Three-Dimensional Image Analysis.

PubMed

Sirenko, Oksana; Hancock, Michael K; Hesley, Jayne; Hong, Dihui; Cohen, Avrum; Gentry, Jason; Carlson, Coby B; Mann, David A

2016-09-01

Cell models are becoming more complex to better mimic the in vivo environment and provide greater predictivity for compound efficacy and toxicity. There is an increasing interest in exploring the use of three-dimensional (3D) spheroids for modeling developmental and tissue biology with the goal of accelerating translational research in these areas. Accordingly, the development of high-throughput quantitative assays using 3D cultures is an active area of investigation. In this study, we have developed and optimized methods for the formation of 3D liver spheroids derived from human iPS cells and used those for toxicity assessment. We used confocal imaging and 3D image analysis to characterize cellular information from a 3D matrix to enable a multi-parametric comparison of different spheroid phenotypes. The assay enables characterization of compound toxicities by spheroid size (volume) and shape, cell number and spatial distribution, nuclear characterization, number and distribution of cells expressing viability, apoptosis, mitochondrial potential, and viability marker intensities. In addition, changes in the content of live, dead, and apoptotic cells as a consequence of compound exposure were characterized. We tested 48 compounds and compared induced pluripotent stem cell (iPSC)-derived hepatocytes and HepG2 cells in both two-dimensional (2D) and 3D cultures. We observed significant differences in the pharmacological effects of compounds across the two cell types and between the different culture conditions. Our results indicate that a phenotypic assay using 3D model systems formed with human iPSC-derived hepatocytes is suitable for high-throughput screening and can be used for hepatotoxicity assessment in vitro.

Customizable 3D Printed ‘Plug and Play’ Millifluidic Devices for Programmable Fluidics

PubMed Central

Tsuda, Soichiro; Jaffery, Hussain; Doran, David; Hezwani, Mohammad; Robbins, Phillip J.; Yoshida, Mari; Cronin, Leroy

2015-01-01

Three dimensional (3D) printing is actively sought after in recent years as a promising novel technology to construct complex objects, which scope spans from nano- to over millimeter scale. Previously we utilized Fused deposition modeling (FDM)-based 3D printer to construct complex 3D chemical fluidic systems, and here we demonstrate the construction of 3D milli-fluidic structures for programmable liquid handling and control of biological samples. Basic fluidic operation devices, such as water-in-oil (W/O) droplet generators for producing compartmentalized mono-disperse droplets, sensor-integrated chamber for online monitoring of cellular growth, are presented. In addition, chemical surface treatment techniques are used to construct valve-based flow selector for liquid flow control and inter-connectable modular devices for networking fluidic parts. As such this work paves the way for complex operations, such as mixing, flow control, and monitoring of reaction / cell culture progress can be carried out by constructing both passive and active components in 3D printed structures, which designs can be shared online so that anyone with 3D printers can reproduce them by themselves. PMID:26558389

A methodological, task-based approach to Procedure-Specific Simulations training.

PubMed

Setty, Yaki; Salzman, Oren

2016-12-01

Procedure-Specific Simulations (PSS) are 3D realistic simulations that provide a platform to practice complete surgical procedures in a virtual-reality environment. While PSS have the potential to improve surgeons' proficiency, there are no existing standards or guidelines for PSS development in a structured manner. We employ a unique platform inspired by game design to develop virtual reality simulations in three dimensions of urethrovesical anastomosis during radical prostatectomy. 3D visualization is supported by a stereo vision, providing a fully realistic view of the simulation. The software can be executed for any robotic surgery platform. Specifically, we tested the simulation under windows environment on the RobotiX Mentor. Using urethrovesical anastomosis during radical prostatectomy simulation as a representative example, we present a task-based methodological approach to PSS training. The methodology provides tasks in increasing levels of difficulty from a novice level of basic anatomy identification, to an expert level that permits testing new surgical approaches. The modular methodology presented here can be easily extended to support more complex tasks. We foresee this methodology as a tool used to integrate PSS as a complementary training process for surgical procedures.

A heterobimetallic Ga/Yb-Schiff base complex for catalytic asymmetric alpha-addition of isocyanides to aldehydes.

PubMed

Mihara, Hisashi; Xu, Yingjie; Shepherd, Nicholas E; Matsunaga, Shigeki; Shibasaki, Masakatsu

2009-06-24

Development of a new heterobimetallic Ga(O-iPr)(3)/Yb(OTf)(3)/Schiff base 2d complex for catalytic asymmetric alpha-additions of isocyanides to aldehydes is described. Schiff base 2d derived from o-vanillin was suitable to utilize cationic rare earth metal triflates with good Lewis acidity in bimetallic Schiff base catalysis. The Ga(O-iPr)(3)/Yb(OTf)(3)/Schiff base 2d complex promoted asymmetric alpha-additions of alpha-isocyanoacetamides to aryl, heteroaryl, alkenyl, and alkyl aldehydes in good to excellent enantioselectivity (88-98% ee).

A predictive numerical model for potential mapping of the gas hydrate stability zone in the Gulf of Cadiz

NASA Astrophysics Data System (ADS)

Leon, R.; Somoza, L.

2009-04-01

This comunication presents a computational model for mapping the regional 3D distribution in which seafloor gas hydrates would be stable, that is carried out in a Geographical Information System (GIS) environment. The construction of the model is comprised of three primary steps, namely (1) the construction of surfaces for the various variables based on available 3D data (seafloor temperature, geothermal gradient and depth-pressure); (2) the calculation of the gas function equilibrium functions for the various hydrocarbon compositions reported from hydrate and sediment samples; and (3) the calculation of the thickness of the hydrate stability zone. The solution is based on a transcendental function, which is solved iteratively in a GIS environment. The model has been applied in the northernmost continental slope of the Gulf of Cadiz, an area where an abundant supply for hydrate formation, such as extensive hydrocarbon seeps, diapirs and fault structures, is combined with deep undercurrents and a complex seafloor morphology. In the Gulf of Cadiz, model depicts the distribution of the base of the gas hydrate stability zone for both biogenic and thermogenic gas compositions, and explains the geometry and distribution of geological structures derived from gas venting in the Tasyo Field (Gulf of Cadiz) and the generation of BSR levels on the upper continental slope.

Multi-AUV Target Search Based on Bioinspired Neurodynamics Model in 3-D Underwater Environments.

PubMed

Cao, Xiang; Zhu, Daqi; Yang, Simon X

2016-11-01

Target search in 3-D underwater environments is a challenge in multiple autonomous underwater vehicles (multi-AUVs) exploration. This paper focuses on an effective strategy for multi-AUV target search in the 3-D underwater environments with obstacles. First, the Dempster-Shafer theory of evidence is applied to extract information of environment from the sonar data to build a grid map of the underwater environments. Second, a topologically organized bioinspired neurodynamics model based on the grid map is constructed to represent the dynamic environment. The target globally attracts the AUVs through the dynamic neural activity landscape of the model, while the obstacles locally push the AUVs away to avoid collision. Finally, the AUVs plan their search path to the targets autonomously by a steepest gradient descent rule. The proposed algorithm deals with various situations, such as static targets search, dynamic targets search, and one or several AUVs break down in the 3-D underwater environments with obstacles. The simulation results show that the proposed algorithm is capable of guiding multi-AUV to achieve search task of multiple targets with higher efficiency and adaptability compared with other algorithms.